CN114088209B

CN114088209B - Infrared detector based on CMOS technology

Info

Publication number: CN114088209B
Application number: CN202110324078.9A
Authority: CN
Inventors: 翟光杰; 武佩; 潘辉; 翟光强
Original assignee: Beijing North Gaoye Technology Co ltd
Current assignee: Beijing North Gaoye Technology Co ltd
Priority date: 2021-03-26
Filing date: 2021-03-26
Publication date: 2023-08-01
Anticipated expiration: 2041-03-26
Also published as: CN114088209A

Abstract

The present disclosure relates to an infrared detector based on a CMOS process, comprising a picture element comprising: the CMOS measuring circuit system and the CMOS infrared sensing structure directly prepared on the CMOS measuring circuit system are prepared by adopting a CMOS process; the CMOS infrared sensing structure comprises a reflecting layer, an infrared conversion structure and a plurality of columnar structures, wherein the columnar structures comprise at least two layers of upright posts which are overlapped and arranged between the reflecting layer and the infrared conversion structure, the reflecting layer comprises a reflecting plate and a supporting base, and the infrared conversion structure is electrically connected with the CMOS measuring circuit system through the columnar structures and the supporting base; the infrared conversion structure comprises an absorption plate and a plurality of beam structures, and the absorption plate is electrically connected with the columnar structure through the corresponding beam structures; at least two infrared detector pixels share at least one columnar structure; the infrared detector pixel also comprises a reinforcing structure; the reinforcing structure is used for enhancing the connection stability between the columnar structure and the infrared conversion structure. The problems of low performance, low pixel scale, low yield and the like of the infrared detector of the traditional MEMS technology are solved.

Description

Infrared detector based on CMOS technology

Technical Field

The disclosure relates to the technical field of infrared detection, in particular to an infrared detector based on a CMOS (complementary metal oxide semiconductor) process.

Background

The fields of monitoring markets, car auxiliary markets, home markets, intelligent manufacturing markets, mobile phone applications and the like have strong demands on uncooled high-performance chips, and have certain demands on the performance of the chips, the consistency of the performance and the price of products, the potential demands of more than one hundred million chips are predicted each year, and the current technological scheme and architecture cannot meet the market demands.

At present, an infrared detector adopts a mode of combining a measuring circuit and an infrared sensing structure, the measuring circuit is prepared by adopting a CMOS (complementary metal Oxide Semiconductor) process, and the infrared sensing structure is prepared by adopting an MEMS (Micro-Electro-Mechanical System) process, so that the following problems exist:

(1) The infrared sensing structure is prepared by adopting an MEMS process, takes polyimide as a sacrificial layer and is not compatible with a CMOS process.

(2) Polyimide is used as a sacrificial layer, so that the problem that the vacuum degree of a detector chip is not affected cleanly due to release exists, the growth temperature of a subsequent film is limited, and the selection of materials is not facilitated.

(3) Polyimide can cause the resonant cavity height inconsistent, and the work dominant wavelength is difficult to guarantee.

(4) The MEMS process is far worse than the CMOS process, and the performance consistency and the detection performance of the chip are restricted.

(5) MEMS has low productivity, low yield and high cost, and cannot realize mass production.

(6) The existing process capability of MEMS is insufficient to support the preparation of a detector with higher performance, smaller line width and thinner film thickness, which is not beneficial to the realization of the miniaturization of chips.

Meanwhile, as each infrared detector pixel is provided with a columnar structure, the columnar structure occupies a larger space, so that the infrared conversion structure area is smaller, and the duty ratio of the infrared detector is smaller; in addition, the structure stability is poor, and the detection sensitivity is low.

Disclosure of Invention

In order to solve the technical problems or at least partially solve the technical problems, the disclosure provides an infrared detector based on a CMOS process, which solves the problems of low performance, low pixel scale, low yield and the like of the infrared detector of the traditional MEMS process, improves the duty ratio and the sensitivity, and improves the structural stability.

The present disclosure provides an infrared detector based on a CMOS process, the infrared detector comprising:

the infrared detector pixels are arranged in an array, each infrared detector pixel comprises a CMOS measurement circuit system and a CMOS infrared sensing structure positioned on the CMOS measurement circuit system, the CMOS measurement circuit system and the CMOS infrared sensing structure are prepared by adopting a CMOS process, and the CMOS infrared sensing structure is directly prepared on the CMOS measurement circuit system;

The upper part of the CMOS measurement circuit system comprises at least one airtight release isolation layer, and the airtight release isolation layer is used for protecting the CMOS measurement circuit system from process influence in the etching process of manufacturing the CMOS infrared sensing structure;

the CMOS manufacturing process of the CMOS infrared sensing structure comprises a metal interconnection process, a through hole process and an RDL process, wherein the CMOS infrared sensing structure comprises at least two metal layers, at least two dielectric layers and a plurality of interconnection through holes;

the CMOS infrared sensing structure comprises a reflecting layer, an infrared conversion structure and a plurality of columnar structures, wherein the reflecting layer, the infrared conversion structure and the columnar structures are positioned on the CMOS measuring circuit system, the columnar structures are positioned between the reflecting layer and the infrared conversion structure, the reflecting layer comprises a reflecting plate and a supporting base, and the infrared conversion structure is electrically connected with the CMOS measuring circuit system through the columnar structures and the supporting base;

the infrared conversion structure comprises an absorption plate and a plurality of beam structures, wherein the absorption plate is used for converting infrared signals into electric signals and is electrically connected with the corresponding columnar structures through the corresponding beam structures;

at least two infrared detector pixels share at least one columnar structure;

The columnar structure comprises at least two layers of upright posts which are overlapped;

the infrared detector pixel also comprises a reinforcing structure; the reinforcing structure is used for enhancing the connection stability between the columnar structure and the infrared conversion structure.

In some embodiments, each layer of the posts may be at least one of a solid metal post, a non-metal solid post, or a hollow post, the material comprising the side walls of the non-metal solid post and the material comprising the side walls of the hollow post each comprising a metal.

In some embodiments, the CMOS infrared sensing structure includes a sacrificial layer, the sacrificial layer is used to make the CMOS infrared sensing structure form a hollowed-out structure, the material constituting the sacrificial layer is silicon oxide, and the sacrificial layer is etched by using a post-CMOS process;

the post-CMOS process etches the sacrificial layer using at least one of vapor phase hydrogen fluoride, carbon tetrafluoride, and trifluoromethane.

In some embodiments, each layer of pillars in the same columnar structure is a same type of pillar; and/or

The upright posts positioned on the same layer are all of the same type.

In some embodiments, the number of layers of the upright posts in the columnar structure is n, n is more than or equal to 2, and is a positive integer; wherein the method comprises the steps of

The n layers of upright posts are solid metal posts;

or n-1 layers of upright posts close to the reflecting layer are solid metal posts, and the nth layer of upright posts are hollow posts;

or n-1 layers of upright posts close to the reflecting layer are all nonmetal solid posts, and the nth layer of upright posts are hollow posts.

In some embodiments, the side wall of the hollow column is formed by combining metal and a medium, and the side wall of the hollow column sequentially comprises a first medium layer, a metal layer and a second medium layer along the radial direction of the hollow column;

the first dielectric layer and the metal layer are U-shaped, and the U-shaped bottom of the metal layer is in contact with the support base or the metal of other upright posts positioned between the hollow post and the support base;

the second dielectric layer is arranged on one side of the metal layer, which is away from the first dielectric layer.

In some embodiments, the metal material comprising the sidewall of the hollow column comprises at least one of titanium, titanium nitride, tantalum, or tantalum nitride, or the metal material comprising the sidewall of the hollow column comprises at least one of titanium tungsten alloy, nichrome, nickel platinum alloy, nickel silicon alloy, nickel, chromium, or platinum;

the dielectric material constituting the side wall of the hollow column comprises at least one of amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide or aluminum oxide.

In some embodiments, the side walls and bottom of the nonmetallic solid posts are formed of a metallic material, and the spaces surrounded by the side walls are filled with a nonmetallic material.

In some embodiments, the non-metallic material comprises at least one of silicon dioxide, silicon nitride, amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide, silicon carbonitride, or aluminum oxide;

the metal material comprises at least one of titanium, titanium nitride, tantalum, or tantalum nitride, or the metal material comprises at least one of titanium tungsten alloy, nichrome, nickel platinum alloy, nickel silicon alloy, nickel, chromium, or platinum.

In some embodiments, the solid metal posts are comprised of a material comprising at least one of aluminum, copper, or tungsten.

In some embodiments, the same columnar structure is shared by at least two adjacent infrared detector pixels.

In some embodiments, the infrared detector pixels are arranged in rows and columns;

at least one columnar structure is shared by two adjacent infrared detector pixels in the same row; and/or

At least one columnar structure is shared by two adjacent infrared detector pixels in the same column.

In some embodiments, the columnar structure comprises a bottom layer of pillars and a top layer of pillars, the bottom layer of pillars connected between the top layer of pillars and the support base, the top layer of pillars connected between the bottom layer of pillars and the infrared conversion structure;

One bottom upright correspondingly supports at least two top uprights;

at least two infrared detector pixels share at least one bottom layer upright post;

each infrared detector pixel is provided with its own top column separately.

In some embodiments, the bottom layer stand column and the top layer stand column are both solid metal stand columns;

or the bottom upright post is a solid metal post, and the top upright post is a nonmetal solid post;

or the bottom upright post is a solid metal post, and the top upright post is a hollow post;

or the bottom upright post is a nonmetal solid post, and the top upright post is a hollow post;

or the bottom upright post is a hollow post, and the top upright post is a solid metal post or a nonmetallic solid post.

In some embodiments, the dimensions of the columns that correspond to support the same infrared detector pixel are all the same;

alternatively, the size of the columns that are shared is larger than the size of the columns that are not shared.

In some embodiments, each of the infrared detector pixels is supported by four of the columnar structures;

or each infrared detector pixel is supported by two columnar structures.

In some embodiments, the reinforcing structure is disposed on a side of the beam structure facing away from the columnar structure;

alternatively, the beam structure includes a hollowed out region at a location corresponding to the columnar structure;

the reinforcement structure comprises a first reinforcement part and a second reinforcement part which are connected with each other;

the first reinforcement part is embedded into the hollowed-out area and is contacted with the columnar structure;

the second reinforcing part covers the surface, deviating from the columnar structure, of the beam structure surrounding the hollowed-out area.

In some embodiments, the material comprising the reinforcing structure comprises at least one of a metal or a medium.

In some embodiments, the metallic material comprising the reinforcing structure comprises at least one of aluminum, copper, tungsten, gold, platinum, chromium, nickel, titanium tungsten alloy, nichrome, nickel platinum alloy, nickel silicon alloy;

the dielectric material constituting the reinforcing structure comprises at least one of amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide or aluminum oxide.

In some embodiments, the reinforcement structure surrounds the sides of the columnar structure and the sides of the beam structure that are contiguous.

In some embodiments, the reinforcing structure extends from the beam structure along a side of the columnar structure in the direction of the reflective layer.

In some embodiments, the reinforcement structure is formed of the same material as the beam structure.

In some embodiments, the columnar structures have an overall height of 1.5 microns or greater and 2.5 microns or less;

the unidirectional width of the cross section of the topmost stand column far away from the reflecting layer is more than or equal to 0.5 micrometer and less than or equal to 3 micrometers.

In some embodiments, the CMOS infrared sensing structure further comprises an adhesion layer;

the adhesion layer covers at least the bottom surface of the columnar structure contacting the support base.

In some embodiments, the adhesive layer is also located between two adjacent layers of the posts.

In some embodiments, the material comprising the adhesion layer comprises at least one of titanium, titanium nitride, tantalum, or tantalum nitride.

In some embodiments, the bottom of the columnar structure is embedded within the support base.

In some embodiments, the infrared detector unit further comprises a dielectric protective layer;

the dielectric protection layer covers the surface of the non-supporting columnar structure of the reflecting layer;

the bottom of the columnar structure is embedded into the dielectric protection layer.

In some embodiments, the infrared detector pixel further comprises an etch stop layer;

And the etching barrier layer at least covers the corner position of the dielectric protection layer.

Compared with the prior art, the technical scheme provided by the embodiment of the disclosure has the following advantages:

(1) The infrared detector pixel provided by the embodiment of the disclosure realizes the integrated preparation of the CMOS measurement circuit system and the CMOS infrared sensing structure on the CMOS production line by using the CMOS process, compared with the MEMS process, the CMOS has no process compatibility problem, solves the technical difficulties faced by the MEMS process, and can reduce the transportation cost and the risk caused by the transportation and other problems by adopting the CMOS process production line process to prepare the infrared detector; the silicon oxide is used as the sacrificial layer of the infrared detector, the silicon oxide is fully compatible with the CMOS process, the preparation process is simple and easy to control, the problem that the vacuum degree of the detector chip is influenced by uncleanness of polyimide release of the sacrificial layer is avoided in the CMOS process, the subsequent film growth temperature is not limited by the material of the sacrificial layer, the design of the sacrificial layer multilayer process can be realized, the process limitation is avoided, the planarization can be easily realized by utilizing the sacrificial layer, and the process difficulty and the possible risks are reduced; the infrared detector prepared by the integrated CMOS technology can realize the targets of high chip yield, low cost, high productivity and large-scale integrated production, and provides a wider application market for the infrared detector; the infrared detector based on the CMOS technology can realize smaller size and thinner film thickness of the characteristic structure, so that the infrared detector has larger duty ratio, lower thermal conductivity and smaller heat capacity, and further has higher detection sensitivity, longer detection distance and better detection performance; the infrared detector based on the CMOS technology can enable the pixel size of the detector to be smaller, realize smaller chip area under the same array pixel, and be more beneficial to realizing chip miniaturization; the infrared detector based on the CMOS technology has mature technology production line and higher technology control precision, can better meet the design requirement, has better consistency of products, is more beneficial to the adjustment performance of the circuit chip and is more beneficial to industrialized mass production;

(2) By arranging at least one columnar structure shared by at least two infrared detector pixels, the number of the columnar structures in the infrared detector can be reduced relative to the arrangement of the respective columnar structures for each infrared detector pixel, so that the space occupied by the columnar structures in the infrared detector is reduced, correspondingly, the effective area occupation ratio in an infrared conversion structure is increased, and the duty ratio of the infrared detector is improved;

(3) The CMOS infrared sensing structure comprises a columnar structure of at least two layers of upright posts which are overlapped, the height of each layer of upright post can be reduced when the whole height of the columnar structure meets the requirement and electric connection between the infrared conversion structure and a supporting base is realized, and the lower the height of the upright post is, the better the steepness of the upright post is, so that each layer of upright post with better steepness is easier to form, the whole steepness of the columnar structure is better, the whole size of the columnar structure can be smaller, the occupied space of the columnar structure is reduced, the effective area of the infrared conversion structure is increased, the duty ratio is further improved, and the detection sensitivity is improved;

(4) Through setting up the infrared sensing structure of CMOS and including reinforced structure, and reinforced structure is used for reinforcing the connection steadiness between columnar structure and the roof beam structure, can strengthen the mechanical stability between columnar structure and the infrared conversion structure to promote the infrared detector pixel and including the structural stability of the infrared detector of this infrared detector pixel.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments of the present disclosure or the solutions in the prior art, the drawings that are required for the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.

Fig. 1 is a schematic perspective view of an infrared detector according to an embodiment of the disclosure;

FIG. 2 is a schematic cross-sectional view of an infrared detector according to an embodiment of the present disclosure;

FIG. 3 is a schematic plan view of an infrared detector according to an embodiment of the disclosure;

FIG. 4 is a schematic plan view of another infrared detector according to an embodiment of the present disclosure;

FIG. 5 is a schematic plan view of an infrared detector according to another embodiment of the present disclosure;

FIG. 6 is a schematic plan view of an infrared detector according to another embodiment of the present disclosure;

FIG. 7 is a schematic cross-sectional view of another infrared detector according to an embodiment of the present disclosure;

FIG. 8 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 9 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 10 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 11 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 12 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 13 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 14 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 15 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 16 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 17 is a schematic cross-sectional view of yet another infrared detector of an embodiment of the present disclosure;

FIG. 18 is a top view of one corrosion barrier structure in an infrared detector pixel of an embodiment of the disclosure;

FIG. 19 is a top view of another corrosion barrier in an infrared detector pixel in an embodiment of the disclosure;

FIG. 20 is a schematic diagram of a CMOS measurement circuitry according to an embodiment of the present disclosure;

FIG. 21 is a schematic cross-sectional view of another infrared detector according to an embodiment of the disclosure;

FIG. 22 is a schematic cross-sectional view of another infrared detector according to an embodiment of the disclosure;

FIG. 23 is a schematic perspective view of another infrared detector according to an embodiment of the disclosure;

FIG. 24 is a schematic cross-sectional view of another infrared detector according to an embodiment of the disclosure;

fig. 25 is a schematic cross-sectional view of another infrared detector according to an embodiment of the disclosure.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, a further description of aspects of the present disclosure will be provided below. It should be noted that, without conflict, the embodiments of the present disclosure and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced otherwise than as described herein; it will be apparent that the embodiments in the specification are only some, but not all, embodiments of the disclosure.

Fig. 1 is a schematic perspective view of an infrared detector according to an embodiment of the disclosure, fig. 2 is a schematic cross-sectional view of an infrared detector according to an embodiment of the disclosure, and fig. 3 is a schematic plan view of an infrared detector according to an embodiment of the disclosure. Fig. 2 shows a partial cross-sectional structure of the infrared detector in the XZ plane, the YZ plane, or a plane extending to form a plane along a certain Z direction, and fig. 3 shows a partial planar structure of the infrared detector in the XY plane, which is only for explaining the structure of the infrared detector provided by the embodiments of the present disclosure, and does not limit the infrared detector provided by the embodiments of the present disclosure. Referring to fig. 1 to 3, the infrared detector 10 includes: the infrared detector pixel 10 is arranged in an array, the infrared detector pixel 10 comprises a CMOS measuring circuit system 1 and a CMOS infrared sensing structure 2, and the CMOS measuring circuit system 1 and the CMOS infrared sensing structure 2 are prepared by adopting a CMOS process; the CMOS infrared sensing structure 2 is directly fabricated on the CMOS measurement circuitry 1.

Specifically, the CMOS infrared sensing structure 2 is configured to convert an external infrared signal into an electrical signal and transmit the electrical signal to the CMOS measurement circuitry 1, where the CMOS measurement circuitry 1 reflects temperature information of a corresponding infrared signal according to the received electrical signal, so as to implement a temperature detection function of the infrared detector. The CMOS measuring circuit system 1 and the CMOS infrared sensing structure 2 are arranged and are prepared by using a CMOS process, the CMOS infrared sensing structure 2 is directly prepared on the CMOS measuring circuit system 1, namely, the CMOS measuring circuit system 1 is prepared by adopting the CMOS process, and then the CMOS infrared sensing structure 2 is continuously prepared by utilizing the CMOS process by utilizing the CMOS production line and parameters of various processes compatible with the CMOS production line.

Therefore, the embodiment of the disclosure realizes the integrated preparation of the CMOS measurement circuit system 1 and the CMOS infrared sensing structure 2 on the CMOS production line by using the CMOS process, compared with the MEMS process, the CMOS has no process compatibility problem, solves the technical difficulties faced by the MEMS process, and can reduce the transportation cost and reduce the risks caused by the transportation and other problems by adopting the CMOS production line process to prepare the infrared detector; the silicon oxide is used as the sacrificial layer of the infrared detector, the silicon oxide is fully compatible with the CMOS process, the preparation process is simple and easy to control, the problem that the vacuum degree of the detector chip is influenced by uncleanness of polyimide release of the sacrificial layer is avoided in the CMOS process, the subsequent film growth temperature is not limited by the material of the sacrificial layer, the design of the sacrificial layer multilayer process can be realized, the process limitation is avoided, the planarization can be easily realized by utilizing the sacrificial layer, and the process difficulty and the possible risks are reduced; the infrared detector prepared by the integrated CMOS technology can realize the targets of high chip yield, low cost, high productivity and large-scale integrated production, and provides a wider application market for the infrared detector; the infrared detector based on the CMOS technology can realize smaller size and thinner film thickness of the characteristic structure, so that the infrared detector has larger duty ratio, lower thermal conductivity and smaller heat capacity, and further has higher detection sensitivity, longer detection distance and better detection performance; the infrared detector based on the CMOS technology can enable the pixel size of the detector to be smaller, realize smaller chip area under the same array pixel, and be more beneficial to realizing chip miniaturization; the infrared detector based on the CMOS technology has mature technology production line and higher technology control precision, can better meet the design requirement, has better consistency of products, is more beneficial to the adjustment performance of the circuit chip and is more beneficial to industrialized mass production.

With continued reference to fig. 1-3, the CMOS infrared sensing structure 2 includes a reflective layer 21 located on the CMOS measurement circuitry 1, an infrared converting structure 23, and a plurality of columnar structures 22, the columnar structures 22 being located between the reflective layer 21 and the infrared converting structure 23, the reflective layer 21 including a reflective plate 212 and a support base 211, the infrared converting structure 23 being electrically connected to the CMOS measurement circuitry 1 through the columnar structures 22 and the support base 211; the infrared conversion structure 23 includes an absorption plate 2301 and a plurality of beam structures 2302, the absorption plate 2301 being configured to convert infrared signals into electrical signals and being electrically connected to the corresponding columnar structures 22 through the corresponding beam structures 2302; at least two infrared detector pixels 10 share at least one columnar structure 22; the columnar structure 22 comprises at least two layers of upright posts which are overlapped; infrared detector pixel 10 also includes a reinforcing structure 24; the reinforcing structure 24 serves to enhance the connection stability between the columnar structure 22 and the infrared converting structure 23.

The reflecting layer 21 is used for reflecting infrared rays to an infrared conversion structure 23 in the CMOS infrared sensing structure and is matched with the resonant cavity to realize secondary absorption of the infrared rays; the columnar structure 22 is located between the reflecting layer 21 and the infrared converting structure 23, and is used for supporting the infrared converting structure 23 in the CMOS infrared sensing structure 2 after the sacrificial layer on the CMOS measuring circuit system 1 is released, the infrared converting structure 23 detects infrared radiation signals and converts the detected infrared radiation signals into electric signals, the electric signals are transmitted to the CMOS measuring circuit system 1 through the columnar structure 22 and the corresponding supporting base 211, and the CMOS measuring circuit system 1 processes the electric signals to reflect temperature information, so that non-contact infrared temperature detection of the infrared detector is realized. Specifically, the CMOS infrared sensing structure 2 outputs a positive electric signal and a ground electric signal through different electrode structures, and the positive electric signal and the ground electric signal are transmitted to the support base 211 electrically connected to the columnar structure 22 through different columnar structures 22. In addition, the reflecting layer 21 includes a reflecting plate 212 and a supporting base 211, a part of the reflecting layer 21 is used as a dielectric medium electrically connected with the CMOS measurement circuitry 1 by the columnar structure 22, that is, the supporting base 211, and the reflecting plate 212 is used for reflecting infrared rays to the infrared conversion structure 23, and cooperates with a resonant cavity formed between the reflecting layer 21 and the infrared conversion structure 23 to realize secondary absorption of the infrared rays, so as to improve infrared absorption rate of the infrared detector and optimize infrared detection performance of the infrared detector.

Specifically, with reference to fig. 2, the infrared conversion structure 23 may structurally include an absorber plate 2301 and a beam structure 2302, the absorber plate 2301 being configured to convert infrared signals into electrical signals and electrically connected to the columnar structures 22 through the corresponding beam structure 2302; meanwhile, the film layer structure of the infrared converting structure 23 may include a thermosensitive layer, an electrode layer, and a passivation layer; wherein the thermosensitive layer is only located on the absorption plate 2301 for converting a temperature signal into an electrical signal, the electrode layer is for adjusting the resistance of the thermosensitive layer, and the electrical signal of the thermosensitive layer is transferred to the CMOS measurement circuitry 1 through the beam structure 2302, and the passivation layer is for protecting the thermosensitive layer and the electrode layer.

Alternatively, the absorber plate 2301 includes a supporting layer, an electrode layer, a heat-sensitive layer and a passivation layer, the beam structure 2302 may include a supporting layer, an electrode layer and a passivation layer, the beam structure 2302 may further include a heat-sensitive layer, the supporting layer is located on a side of the passivation layer adjacent to the CMOS measurement circuitry 1, the electrode layer and the heat-sensitive layer are located between the supporting layer and the passivation layer, the passivation layer covers the electrode layer, the heat-sensitive layer may be disposed to cover a position where the beam structure 2302 is located, and the heat conduction of the beam structure 2302 is reduced by using a characteristic that a heat-sensitive material such as amorphous silicon, amorphous germanium or amorphous silicon germanium has a small heat conductivity, and the heat-sensitive layer may replace the supporting layer as a supporting material of the beam structure 2302 or replace the passivation layer as an electrode protection material of the beam structure 2302.

Specifically, the supporting layer is used for supporting the upper film layer in the infrared conversion structure 23 after releasing the sacrificial layer, the thermosensitive layer is used for converting the infrared temperature detection signal into an infrared detection electric signal, the electrode layer is used for transmitting the infrared detection electric signal converted by the thermosensitive layer to the CMOS measurement circuit system 1 through the beam structures 2302 at the left side and the right side, the two beam structures 2302 respectively transmit positive and negative signals of the infrared detection electric signal, the readout circuit in the CMOS measurement circuit system 1 realizes non-contact infrared temperature detection through analysis of the obtained infrared detection electric signal, and the passivation layer is used for protecting the electrode layer from oxidation or corrosion. The thermosensitive layer may be located above the electrode layer or below the electrode layer. The heat sensitive layer and the electrode layer in the absorbing plate 2301 can be protected by arranging the corresponding absorbing plate 2301 in a closed space formed by the supporting layer and the passivation layer, and the electrode layer in the beam structure 2302 can be protected by arranging the corresponding electrode layer in a closed space formed by the supporting layer and the passivation layer.

As an example, the material constituting the thermosensitive layer may be provided to include at least one of amorphous silicon, amorphous germanium, amorphous silicon germanium, titanium oxide, vanadium oxide, or titanium vanadium oxide, the material constituting the support layer may include one or more of amorphous carbon, aluminum oxide, amorphous silicon, amorphous germanium, or amorphous germanium silicon, the material constituting the electrode layer may include one or more of titanium, titanium nitride, tantalum nitride, titanium tungsten alloy, nichrome, nickel, or chromium, and the material constituting the passivation layer may include one or more of amorphous carbon, aluminum oxide, amorphous silicon, amorphous germanium, or amorphous germanium silicon. In addition, when the absorbing plate 2301 includes a heat-sensitive layer, and the heat-sensitive layer is made of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium, the supporting layer and/or the passivation layer on the beam structure 2302 may be replaced by the heat-sensitive layer, which is beneficial to reducing the heat conductivity of the beam structure 2302 and further improving the infrared response rate of the infrared detector because the heat conductivity of the amorphous silicon, amorphous germanium or amorphous silicon germanium is smaller.

In other embodiments, the infrared detector pixel may further include other structures, which are not described herein in detail or limited thereto.

The reflecting layer 21 includes a reflecting plate 212 and a supporting base 211, the reflecting plate 212 reflects infrared radiation, the supporting base 211 is electrically connected with the columnar structure 22 and the CMOS measurement circuitry 1, respectively, when the infrared converting structure 23 detects an infrared radiation signal and converts the detected infrared radiation signal into an electrical signal, the electrical signal can be transmitted to the CMOS measurement circuitry 1 through the columnar structure 22 and the supporting base 211, and the CMOS measurement circuitry 1 receives the electrical signal.

Wherein, at least one airtight release isolation layer (not shown in the figure) may be further included above the CMOS measurement circuitry 1, where the airtight release isolation layer is used to protect the CMOS measurement circuitry 1 from the process during the etching process for manufacturing the CMOS infrared sensing structure 2.

Optionally, a hermetic release isolation layer is located at an interface between the CMOS measurement circuitry 1 and the CMOS infrared sensing structure 2 and/or in the CMOS infrared sensing structure 2, the hermetic release isolation layer is used to protect the CMOS measurement circuitry 1 from corrosion when the sacrificial layer is released by performing an etching process, and the CMOS process corrosion resistant material used for the hermetic release isolation layer includes at least one of silicon, germanium, a silicon-germanium alloy, amorphous silicon, amorphous germanium, amorphous silicon-germanium, amorphous carbon, silicon carbide, aluminum oxide, silicon nitride, or silicon carbonitride.

Illustratively, a closed release insulating layer is located in the CMOS infrared sensing structure 2, and the closed release insulating layer may be located above a metal interconnection layer (also referred to as a "metal layer") of the reflective layer 21, where the closed release insulating layer encapsulates the columnar structure 22, and by providing the closed release insulating layer encapsulates the columnar structure 22, on the one hand, the closed release insulating layer may be used as a support at the columnar structure 22, so that the stability of the columnar structure 22 is improved, and the electrical connection between the columnar structure 22 and the infrared conversion structure 23 and the support base 211 is ensured. On the other hand, the airtight release insulating layer coating the columnar structure 22 can reduce the contact between the columnar structure 22 and the external environment, reduce the contact resistance between the columnar structure 22 and the external environment, further reduce the noise of the infrared detector pixels and improve the detection sensitivity of the infrared detector. In addition, the resonant cavity of the infrared detector is realized through the vacuum cavity after the silicon oxide sacrificial layer is released, the reflecting layer 21 is used as the reflecting layer of the resonant cavity, the sacrificial layer is positioned between the reflecting layer 21 and the infrared conversion structure 23, and when at least one layer of airtight release isolation layer positioned on the reflecting layer 21 is used as a part of the resonant cavity, the silicon, the germanium, the silicon germanium alloy, the amorphous silicon, the amorphous germanium or the amorphous silicon germanium is selected, the reflecting effect of the reflecting layer is not influenced, the height of the resonant cavity can be reduced, the thickness of the sacrificial layer is further reduced, and the release difficulty of the sacrificial layer formed by silicon oxide is reduced. In addition, a sealed release isolation layer and the columnar structure 22 are arranged to form a sealed structure, so that the CMOS measurement circuit system 1 is completely separated from the sacrificial layer, and the protection of the CMOS measurement circuit system 1 is realized.

Alternatively, the hermetic release isolation layer 11 is located at an interface between the CMOS measurement circuitry 1 and the CMOS infrared sensing structure 2, for example, the hermetic release isolation layer is located between the reflective layer 21 and the CMOS measurement circuitry 1, that is, the hermetic release isolation layer is located under the metal interconnection layer of the reflective layer 21, and the support base 211 is electrically connected to the CMOS measurement circuitry 1 through a via penetrating the hermetic release isolation layer, as can be seen in fig. 24. Specifically, since the CMOS measurement circuitry 1 and the CMOS infrared sensing structure 2 are both formed by using CMOS processes, after the CMOS measurement circuitry 1 is formed by the preparation, a wafer including the CMOS measurement circuitry 1 is transferred to the next process to form the CMOS infrared sensing structure 2 by the preparation, and since silicon oxide is the most commonly used dielectric material in the CMOS process, silicon oxide is mostly used as an insulating layer between metal layers on the CMOS circuit, if no insulating layer is used as a barrier when silicon oxide with a thickness of about 2um is corroded, the circuit will be seriously affected, and in order to release the silicon oxide of the sacrificial layer, the silicon oxide medium on the CMOS measurement circuitry will not be corroded, and a sealed release insulating layer is provided. After the preparation and formation of the CMOS measurement circuitry 1, a closed release isolation layer is prepared and formed on the CMOS measurement circuitry 1, the CMOS measurement circuitry 1 is protected by using the closed release isolation layer, and in order to ensure the electrical connection between the support base 211 and the CMOS measurement circuitry 1, after the preparation and formation of the closed release isolation layer, an etching process is adopted to form a through hole in a region of the closed release isolation layer corresponding to the support base 211, and the electrical connection between the support base 211 and the CMOS measurement circuitry 1 is realized through the through hole. In addition, a sealing release isolation layer and a supporting base 211 are arranged to form a sealing structure, so that the CMOS measurement circuit system 1 is completely separated from the sacrificial layer, and the protection of the CMOS measurement circuit system 1 is realized.

Or, in the infrared detector, at least one layer of airtight release isolation layer is disposed at the interface between the CMOS measurement circuitry 1 and the CMOS infrared sensing structure 2, and at least one layer of airtight release isolation layer is disposed in the CMOS infrared sensing structure 2, that is, at least one layer of airtight release isolation layer is disposed between the reflective layer 21 and the CMOS measurement circuitry 1, and at least one layer of airtight release isolation layer is disposed on the reflective layer 21, which can refer to fig. 25, and the effects are the same as above, and are not repeated herein.

Exemplary materials for the hermetic release barrier layer include silicon, germanium, silicon-germanium alloy, amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide, aluminum oxide, silicon nitride, or silicon carbonitrideAt least one of the sealing release barrier layers has a thickness of not less thanLess than or equal to->Specifically, silicon, germanium, silicon germanium alloy, amorphous silicon, amorphous germanium, amorphous carbon, silicon carbide, aluminum oxide, silicon nitride and silicon carbonitride are all CMOS process corrosion resistant materials, i.e., these materials are not corroded by the sacrificial layer release agent, so the hermetic release barrier layer can be used to protect the CMOS measurement circuitry 1 from corrosion when the sacrificial layer is released by the corrosion process. In addition, the sealed release isolation layer covers the CMOS measurement circuitry 1, and the sealed release isolation layer can also be used for protecting the CMOS measurement circuitry 1 from process influence in the etching process of manufacturing the CMOS infrared sensing structure 2. In addition, when at least one seal release insulating layer is disposed on the reflective layer 21, the material constituting the seal release insulating layer is selected from at least one of silicon, germanium, silicon germanium alloy, amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide, aluminum oxide, silicon nitride and silicon carbonitride, and the thickness of the first dielectric layer is greater than Less than or equal to->When the stability of the columnar structure 22 is improved by arranging the airtight release isolation layer, the airtight release isolation layer hardly influences the reflection process in the resonant cavity, so that the airtight release isolation layer can be prevented from influencing the reflection process of the resonant cavity, and further, the airtight release isolation layer is prevented from influencing the detection sensitivity of the infrared detector.

The CMOS fabrication process of the CMOS infrared sensing structure 2 includes a metal interconnect process, a via process, and an RDL process, and the CMOS infrared sensing structure 2 includes at least two metal interconnect layers, at least two dielectric layers, and a plurality of interconnect vias to build and communicate with the various structural components in the infrared detector.

Illustratively, the dielectric layer includes at least a sacrificial layer and a heat-sensitive dielectric layer, the heat-sensitive dielectric layer includes at least a heat-sensitive layer, and may further include a supporting layer and/or a passivation layer, and the metal interconnect layer includes at least a reflective layer 21 and an electrode layer; the heat-sensitive medium layer comprises heat-sensitive materials with the temperature coefficient of resistance larger than a set value, the temperature coefficient of resistance can be larger than or equal to 0.015/K, for example, the heat-sensitive materials with the temperature coefficient of resistance larger than the set value form the heat-sensitive layer in the heat-sensitive medium layer, and the heat-sensitive medium layer is used for converting temperature changes corresponding to infrared radiation absorbed by the heat-sensitive medium layer into resistance changes, so that infrared target signals are converted into signals capable of realizing electric reading through the CMOS measuring circuit system 1.

Specifically, the metal interconnection process is used for realizing the electrical connection of an upper metal interconnection layer and a lower metal interconnection layer, the through hole process is used for forming an interconnection through hole for connecting the upper metal interconnection layer and the lower metal interconnection layer, the RDL process is a rewiring layer process, specifically, a layer of metal is newly distributed above the top metal of the circuit and is electrically connected with a tungsten column of the top metal of the circuit, the RDL process is adopted to prepare a reflecting layer in the infrared detector on the top metal of the CMOS measuring circuit system 1, and a supporting base on the reflecting layer is electrically connected with the top metal of the CMOS measuring circuit system 1. In addition, the heat-sensitive medium layer comprises a heat-sensitive material with a temperature coefficient of resistance larger than a set value, and the temperature coefficient of resistance can be larger than or equal to 0.015/K, for example, so that the detection sensitivity of the infrared detector is improved.

In addition, the CMOS fabrication process of the CMOS measurement circuitry 1 may also include a metal interconnection process and a via process, where the CMOS measurement circuitry 1 includes a metal interconnection layer, a dielectric layer, and a silicon substrate at the bottom, which are disposed at intervals, and the upper and lower metal interconnection layers are electrically connected through vias.

Alternatively, the sacrificial layer is used to form the CMOS infrared sensing structure 2 into a hollowed-out structure, the material constituting the sacrificial layer is silicon oxide, and the sacrificial layer is etched by using a post-CMOS process, and the post-CMOS process may etch the sacrificial layer by using at least one of gas phase hydrogen fluoride, carbon tetrafluoride and trifluoromethane, for example. Specifically, a sacrificial layer (not shown in the figure) is arranged between the reflecting layer and the beam structure, and when the sealing release isolation layer is arranged on the reflecting layer, the sacrificial layer is arranged between the sealing release isolation layer and the beam structure, the material forming the sacrificial layer is silicon oxide so as to be compatible with the CMOS process, and the post-CMOS process, namely, the post-CMOS process can be adopted to corrode the sacrificial layer so as to release the sacrificial layer in the final infrared detection chip product.

In the infrared detector pixels, at least one columnar structure 22 is shared by at least two infrared detector pixels 10, and compared with each columnar structure 22 which is respectively arranged for each infrared detector pixel 10, the number of the columnar structures 22 in the infrared detector can be reduced, so that the space occupied by the columnar structures 22 in the infrared detector is reduced, correspondingly, the effective area occupation ratio in the infrared conversion structure 23 is increased, and the duty ratio of the infrared detector is improved.

Meanwhile, through setting up the column structure 22 of the at least two-layer stand that CMOS infrared sensing structure 2 set up including adopting the stack, can be when the whole height of column structure 22 satisfies the demand and realizes the electricity between infrared conversion structure 23 and the support base 211 and be connected, reduce the height of each layer stand, because the height of stand is lower, its steepness is better, from this, each layer stand that the steepness is better is formed to the higher ease, thereby make the holistic steepness of column structure 22 better, its overall dimension can accomplish littleer, so be favorable to reducing the space that column structure 22 takes up, thereby increase the effective area of infrared conversion structure 23, and then improve the duty cycle, improve the detection sensitivity.

Meanwhile, the CMOS infrared sensing structure 2 comprises the reinforcing structure 24, and the reinforcing structure 24 is used for enhancing the connection stability between the columnar structure 22 and the beam structure 2302, so that the mechanical stability between the columnar structure 22 and the infrared conversion structure 23 can be enhanced, and the structural stability of the infrared detector pixel and the infrared detector comprising the infrared detector pixel can be improved.

The manner in which the columns of structures 22 are superimposed in particular and the manner in which they are shared between the infrared detector pixels is exemplified hereinafter.

Illustratively, fig. 1 shows that the infrared detector pixels 10 are arranged in 3 rows and 3 columns, but the infrared detector provided in the embodiments of the present disclosure is not limited thereto.

In other embodiments, the number and arrangement of the infrared detector pixels 10 in the infrared detector may also be set based on the requirements of the infrared detector, which is not limited herein.

Illustratively, in the cross-sectional structure of the infrared detector pixel shown in fig. 2, the reflective layer 21 is only illustratively shown to include one reflective plate 212 and two support bases 211, and correspondingly, the infrared detector pixel includes two columnar structures 22; the infrared detector pixels in the corresponding schematic three-dimensional structure may include two or four columnar structures 22, but are not limited to the infrared detector pixels provided in the embodiments of the present disclosure.

In other embodiments, the number of columnar structures 22 in an infrared detector pixel may be set based on its structural requirements, and is not limited herein.

Illustratively, fig. 2 shows that one columnar structure 22 may be shared by two infrared detector pixels 10 adjacent to each other, and fig. 3 shows that two columnar structures 22 located in the middle of two adjacent infrared detector pixels may be shared by two infrared detector pixels 10, which may reduce the number of columnar structures 22 and increase the duty ratio of the infrared detector.

In other embodiments, the sharing of columnar structures 22 may be provided in other ways, as will be exemplarily described below in connection with fig. 3-6.

In some embodiments, with continued reference to fig. 2 and 3, the same columnar structure 22 is common to at least two adjacent infrared detector pixels 10.

The arrangement is simple in connection relation, no cross-region connection line exists, the overall structure of the infrared detector is simple, and the process difficulty is low; on the other hand, the larger the number of infrared detector pixels 10 sharing the same columnar structure 22, the smaller the total number of columnar structures 22, which is more advantageous for improving the duty ratio.

Illustratively, in FIGS. 2 and 3, the same columnar structure 22 is common to two adjacent infrared detector pixels 10. In other embodiments, the same columnar structure 22 may also be shared by three, four, or more adjacent infrared detector pixels when the infrared detector pixels are otherwise arranged, as not limited herein.

In some embodiments, to reduce the number of columnar structures 22 as much as possible, i.e. to increase the duty cycle of the infrared detector as much as possible, each infrared detector pixel 10 may also be arranged to share as many columnar structures 22 as possible with the infrared detector pixels 10 adjacent thereto.

Illustratively, with reference to FIG. 1, an infrared detector pixel located at an intermediate position may share its respective columnar structure at four apex angle positions with infrared detector pixels surrounding 8 peripheral positions thereof; at this time, each columnar structure is shared by four infrared detector pixels, which can be understood with reference to fig. 6 hereinafter.

In some embodiments, fig. 4 is a schematic plan view of another infrared detector according to an embodiment of the disclosure, fig. 5 is a schematic plan view of yet another infrared detector according to an embodiment of the disclosure, and fig. 6 is a schematic plan view of yet another infrared detector according to an embodiment of the disclosure. Based on FIG. 1 and referring to FIGS. 4-6, the infrared detector pixels 10 are arranged in rows and columns; at least one columnar structure 22 is shared by two adjacent infrared detector pixels 10 in the same row; and/or two infrared detector pixels 10 adjacent in the same column share at least one columnar structure 22.

In fig. 4 to 6, the X direction is taken as the row direction, the Y direction is taken as the column direction, and the columnar structure 22 can be shared only between two adjacent infrared detector pixels 10 in the same row, as shown in fig. 5; or columnar structures 22 may be common only between two adjacent infrared detector pixels 10 of the same column, as in fig. 4; or columnar structures 22 are shared between adjacent infrared detector pixels in both rows and columns, as in fig. 6.

Illustratively, referring to FIG. 4, when columnar structures 22 are shared only in the column direction, the same columnar structure 22 is shared by two infrared detector pixels (shown as Y11 and Y12, respectively) that are adjacent in the column direction.

Illustratively, referring to FIG. 5, when columnar structures 22 are shared only in the row direction, the same columnar structure 22 is shared by two infrared detector pixels (shown as X11 and X12, respectively) that are adjacent in the row direction.

Illustratively, referring to FIG. 6, when columnar structures 22 are shared in both the row and column directions, the same columnar structure 22 is shared by four infrared detector pixels (shown as Z11, Z12, Z13, and Z14, respectively) that are immediately adjacent in the row and column directions.

In other embodiments, when the infrared detector pixels are arranged in other manners, the columnar structure may also realize sharing in other manners, which is not described herein in detail or limited.

In some embodiments, with continued reference to fig. 2, columnar structure 22 includes at least two layers of posts superimposed; each layer of the columns are arranged in a one-to-one correspondence manner.

At least two layers of columns which are overlapped in the same columnar structure 22 are taken as a whole and can be used for at least two infrared detector pixels together, so that the total number of the columnar structures 22 can be reduced, and the duty ratio of the infrared detectors can be improved; meanwhile, the columnar structure 22 is formed by superposing at least two layers of columns, when the total height of the columnar structure 22 is equivalent, the height of each layer of columns can be reduced relative to the structure of a single-layer column, and as the lower the height of the column is, the better the steepness of the column is, therefore, each layer of column with better steepness is easier to form, the whole steepness of the columnar structure is better, the whole size of the columnar structure can be smaller, the occupied space of the columnar structure 22 is reduced, the effective area of the infrared conversion structure is increased, the duty ratio is further improved, and the detection sensitivity is improved.

In some embodiments, FIGS. 7-15 illustrate various different infrared detector configurations provided by embodiments of the present disclosure, respectively. Referring to fig. 7-15, columnar structure 22 includes a bottom layer of posts (shown as second layer of posts 222) connected between the top layer of posts and support base 211, and a top layer of posts (shown as first layer of posts 221) connected between the bottom layer of posts and infrared conversion structure 23; one bottom layer upright correspondingly supports at least two (two are shown) top layer uprights; at least two (three are shown) infrared detector pixels 10 share at least one (two are shown) underlying column; each infrared detector pixel 10 is provided with its own top column.

So set up, the temperature of lower floor's post 222 is the same with the temperature of CMOS measurement circuitry 1 basically, only shares lower floor's post 222 between the infrared detector pixel, and does not share upper column 221, then can improve the thermal cross phenomenon between the infrared detector pixel that shares same lower floor's post 222, weakens the mutual influence between them, avoids the crosstalk promptly, improves the detection precision.

It should be noted that, since the lower column 222 may be shared and the upper column 221 is not shared, the number of upper columns 221 supported on the same lower column 222 is the maximum value of the number of infrared detector pixels that can share the lower column 222 at the same time. Optionally, to fully utilize the space in the infrared detector, it is ensured that the infrared detector has a higher duty cycle, and the number of upper pillars 221 supported on the same lower pillar 222 is equal to the number of infrared detector pixels sharing the lower pillar 222 at the same time.

In the above embodiments, the pillar may be a hollow pillar or a solid pillar, may be a metal solid pillar, or may be a non-metal filled solid pillar with a metal shell, but is not limited thereto.

In some embodiments, the bottom and top posts are solid metal posts, see fig. 2, 12, 13, 14, or 15; or the bottom upright post is a solid metal post, and the top upright post is a nonmetal solid post, see fig. 10; or the bottom upright post is a solid metal post, and the top upright post is a hollow post, see fig. 8; or the bottom upright post is a nonmetal solid post, and the top upright post is a hollow post, see figure 9; or the bottom upright post is a hollow post, and the top upright post is a solid metal post, see fig. 11; or the bottom upright post is a hollow post, and the top upright post is a nonmetal solid post; or the bottom and top posts are hollow posts, see fig. 7.

Wherein, the double-layer solid metal column is supported between the infrared conversion structure 23 and the support base 211, so that the space occupied by the columnar structure 22 is reduced to improve the duty ratio, thereby improving the detection sensitivity, and meanwhile, the solid metal column has better mechanical stability, thereby being beneficial to improving the support stability between the support base 211 and the infrared conversion structure 23, thereby improving the structural stability of the infrared sensor pixel and the infrared detector comprising the infrared sensor pixel; meanwhile, the resistance of the solid metal column is relatively small, so that signal loss in the electric signal transmission process between the infrared conversion structure 23 and the CMOS measurement circuit system 1 is reduced, and the detection performance of the infrared detector is improved; in addition, the size of the solid metal column is easier to accurately control, smaller chip size requirements are met, and miniaturization of the infrared detector is achieved.

Or, the columnar structure 22 of the solid metal column and the hollow column are used for connecting the infrared conversion structure 23 and the support base 211, so that on one hand, the corresponding effect of the solid metal column can be realized; on the other hand, since the side wall of the hollow column is formed by combining metal and a medium, the columnar structure 22 comprising the hollow column can ensure that the infrared conversion structure 23 can realize electric connection between the support base 211 and the CMOS measurement circuit system 1, and meanwhile, the columnar structure 22 can be used for reducing heat conduction, so that the influence of heat radiation generated by the columnar structure 22 on an electric signal generated by the infrared conversion structure 23 is reduced, and the detection performance of an infrared detector pixel and an infrared detector comprising the infrared detector pixel is improved.

Or, the columnar structure 22 of the non-metal solid column superimposed hollow column is used to connect the infrared conversion structure 23 and the support base 211, so that the effect corresponding to the hollow column can be achieved, and meanwhile, the effect corresponding to the non-metal solid column is achieved, specifically including: the side walls and the bottom (side walls and bottom are shown by 222) of the nonmetal solid column are formed by metal materials, and the space 221 surrounded by the side walls is filled with nonmetal materials, so that on one hand, the heat conduction of the columnar structure 22 can be reduced, the influence of the heat radiation of the columnar structure 22 on the electric signal of the infrared conversion structure 23 can be reduced, and the detection performance can be improved; on the other hand, nonmetallic materials are filled in the space surrounded by the side wall, so that the mechanical stability of the columnar structure 22 is improved, the supporting stability of the columnar structure 22 between the supporting base 211 and the infrared conversion structure 23 is improved, the infrared detector pixels and the overall structural stability of the infrared detector comprising the infrared detector pixels are improved, and good structural stability and detection performance are achieved.

In other embodiments, when the columnar structure 22 is a combination of other column types, the infrared detector including the columnar structure can have the effects of the various columns, which are not described herein

Thus, when columnar structure 22 includes dual-layer columns, the type of each column may be set based on the requirements of the infrared detector pixel and the effects achievable by the various columns, which are not limited herein.

In some embodiments, the number of layers of the pillars in columnar structure 22 is n, n++2, and is a positive integer; wherein, n layers of upright posts are solid metal posts; or n-1 layers of upright posts close to the reflecting layer 21 are solid metal posts, and the nth layer of upright posts are hollow posts; or n-1 layer of upright posts close to the reflecting layer 21 are all nonmetal solid posts, and the nth layer of upright posts are hollow posts.

Illustratively, fig. 16 is a schematic cross-sectional structure of still another infrared detector pixel according to an embodiment of the disclosure, which shows a structure of an infrared detector pixel including three columns in columnar structure 22, wherein two columns (shown as second layer column 222 and third layer column 223) near reflective layer 21 are solid metal columns, and the uppermost (shown as first layer column 221) is a hollow column.

In other embodiments, the number of columns in the columnar structure 22 may be three or more, and each layer of columns may be any one of a solid metal column, a non-metal solid column and a hollow column, which may be set based on the requirements of the infrared detector pixel and the process requirements of CMOS, and is not limited herein.

Thus, columnar structure 22 may be a two-layered column, or may be three or more layers of columns; the pillars may be any combination of metal solid pillars, hollow pillars, and nonmetal solid pillars, and may be set based on requirements of infrared detector pixels and requirements of CMOS process, which is not limited herein.

In some embodiments, each layer of posts may be at least one of a solid metal post, a non-metal solid post, or a hollow post, with the material comprising the side walls of the non-metal solid post and the material comprising the side walls of the hollow post each comprising metal.

Thus, by utilizing the conductivity of the metal and by utilizing the support property of the columnar structure 22 as a whole, the infrared conversion structure 23 and the support base 211 can be electrically connected and supported.

In some embodiments, with continued reference to fig. 7-16, each layer of pillars in the same columnar structure 22 is a same type of pillar; and/or the columns positioned on the same layer are all columns of the same type.

Wherein each layer of upright posts in the same columnar structure 22 is a solid metal post; or all are nonmetallic solid columns or all are hollow columns. By this arrangement, the number of columns in the same columnar structure 22 can be reduced, which is advantageous for simplifying the preparation process of the columnar structure.

And/or the upright posts positioned on the same layer are solid metal posts; or all are nonmetallic solid columns or all are hollow columns. By the arrangement, the upright posts positioned on the same layer can be formed by adopting the same process step, and the preparation process of the columnar structure is facilitated to be simplified.

In other embodiments, the same columnar structure 22 may further include a plurality of columns of different types, and the same layer may also be provided with a plurality of columns of different types, which may be provided based on the requirements of the infrared detector pixels, which is not limited herein.

In some embodiments, the side wall of the hollow column is formed by combining metal and a medium, and the side wall of the hollow column sequentially comprises a first medium layer, a metal layer and a second medium layer along the radial direction of the hollow column; the first dielectric layer and the metal layer are both U-shaped, and the U-shaped bottom of the metal layer is in contact with the support base 211 or the metal of other upright posts positioned between the hollow post and the support base 211; the second dielectric layer is arranged on one side of the metal layer, which is away from the first dielectric layer.

The metal layer may be formed of at least one metal material in the following embodiments, and the first dielectric layer and the second dielectric layer may be formed of at least one dielectric material in the following embodiments, and may be the same or different, but are not limited thereto.

Wherein the metal layer is sandwiched between the first dielectric layer, the second dielectric layer, and the support base 211 (or the metal of other posts). Specifically, the U-shaped sidewall of the metal layer is sandwiched between the U-shaped sidewall of the first dielectric layer and the second dielectric layer, and the U-shaped bottom of the metal layer is sandwiched between the U-shaped bottom of the first dielectric layer and the support base 211 (or the metal of other posts). Therefore, the hollow column comprising the metal layer is electrically connected with the infrared conversion structure 23, the support base 211 or other layer upright columns, and insulation protection is realized inside and outside the metal layer by utilizing the first dielectric layer and the second dielectric layer, so that the performance attenuation of the metal layer is slowed down, and the service life of the infrared detector is prolonged; and by utilizing the multi-film structure of the columnar structure 22, multi-film support can be realized, which is beneficial to improving the structural stability.

In addition, the metal layer is set to be U-shaped structure, the bottom support and contact of the hollow column are realized by utilizing the U-shaped bottom of the metal layer, the contact area between the metal layer of the hollow column and the support base 211 or other layer upright posts can be increased, the contact resistance is reduced, the loss of electric signals is reduced, and the detection performance is improved.

In other embodiments, the hollow column can be provided as a hollow column with other structures, such as a barrel-shaped structure, which has simpler structure form and smaller process difficulty; alternatively, the hollow column may be provided in other hollow column structures known to those skilled in the art, and are not described herein in detail.

In some embodiments, the metal material constituting the sidewalls of the hollow pillars includes at least one of titanium (Ti), titanium nitride (TiN), tantalum (Ta), or tantalum nitride (TaN), or the metal material constituting the sidewalls of the hollow pillars includes at least one of titanium tungsten alloy (TiW), nickel chromium alloy (NiCr), nickel platinum alloy (NiPt), nickel silicon alloy (NiSi), nickel (Ni), chromium (Cr), or platinum (Pt); the dielectric material constituting the side wall of the hollow column comprises amorphous silicon (a-Si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SiGe), amorphous carbon (a-C), silicon carbide (SiC) or trioxideAluminium di (Al) ₂ O ₃ ) At least one of them.

The above metals or metal alloys have better contact performance and electrical performance, and the hollow column can be firmly connected with the infrared conversion structure 23, the support base 211 or other layer of upright columns by utilizing the better contact performance, so that the hollow column is not easy to fall off, thereby being beneficial to enhancing the structural stability; by utilizing the good electrical property, the loss of the electric signal is small when the hollow column transmits the electric signal between the infrared conversion structure 23 and the support base 211, and the detection performance is improved. In addition, the heat conduction of the various metals or metal alloys is smaller, so that the heat conduction of the columnar structure 22 is smaller, the influence of the heat radiation generated by the columnar structure 22 on the electric signal generated by the infrared conversion structure 23 is reduced, and the detection performance is improved.

In other embodiments, the metal material that forms the sidewalls of the hollow columns may also include other materials known to those skilled in the art, as long as the requirements of the infrared detector pixel are met, which is not limited herein.

Wherein, the dielectric materials are not corroded by VHF, so that the columnar structure 22 is not corroded when the sacrificial layer is taken out by VHF corrosion in the subsequent process steps; meanwhile, the mechanical strength of the joint can be enhanced, and the falling off caused by the infirm connection between the upper structure (namely the infrared conversion structure 23) and the columnar structure 22 is prevented, so that the structural stability is enhanced.

In other embodiments, the dielectric material that forms the sidewalls of the hollow columns may also include other materials known to those skilled in the art, as long as the requirements of the infrared detector pixel are met, which is not limited herein.

In some embodiments, the sidewalls and bottom of the nonmetallic solid posts are formed of a metallic material, and the spaces enclosed by the sidewalls are filled with the nonmetallic material.

Therefore, the side wall and the bottom of the nonmetal solid column are electrically connected, and meanwhile, the filled nonmetal material can be used for realizing stable support, so that the structural stability is improved.

In some embodiments, the non-metallic material comprises silicon dioxide (SiO ₂ ) Silicon nitride (SiNx), amorphous silicon (a-Si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SiGe), amorphous carbon (a-C), silicon carbide (SiC), silicon carbonitride (SiCN) or aluminum oxide (Al) ₂ O ₃ ) At least one of (a) and (b); the metal material includes at least one of titanium (Ti), titanium nitride (TiN), tantalum (Ta), or tantalum nitride (TaN), or the metal material includes at least one of titanium tungsten alloy (TiW), nickel chromium alloy (NiCr), nickel platinum alloy (NiPt), nickel silicon alloy (NiSi), nickel (Ni), chromium (Cr), or platinum (Pt).

The mechanical stability of the various nonmetallic materials is good, and at least one of the nonmetallic solid columns is used for filling the space surrounded by the side wall of the nonmetallic solid column, so that the overall supporting performance of the nonmetallic solid column is improved, and the structural stability is improved. Meanwhile, silicon (Si), germanium (Ge), amorphous silicon (a-Si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SiGe), amorphous carbon (a-C), silicon carbide (SiC) and aluminum oxide (Al) ₂ O ₃ ) The metal is not corroded by VHF, so that the nonmetal solid column is not corroded when the sacrificial layer is taken out by VHF corrosion in the subsequent process step; meanwhile, the mechanical strength of the connection part can be enhanced, and the connection between the infrared conversion structure 23, the support base 211 or other layers of upright posts is prevented from being loose, so that the structural stability is enhanced.

In other embodiments, the nonmetallic materials used to fill the nonmetallic solid pillars may also include other materials known to those skilled in the art, as long as the requirements of the infrared detector pixels are met, which are not limited herein.

The above metals or metal alloys have better contact performance and electrical performance, and the nonmetal solid columns can be firmly connected with the infrared conversion structure 23, the support base 211 or other layer upright columns by utilizing the better contact performance, so that the nonmetal solid columns are not easy to fall off, thereby being beneficial to enhancing the structural stability; by utilizing the good electrical property, the loss of the electrical signal is small when the nonmetal solid column transmits the electrical signal between the infrared conversion structure 23 and the support base 211, and the detection performance is improved. In addition, the heat conduction of the various metals or metal alloys is smaller, so that the heat conduction of the columnar structure 22 is smaller, the influence of the heat radiation generated by the columnar structure 22 on the electric signal generated by the infrared conversion structure 23 is reduced, and the detection performance is improved.

In other embodiments, the metal materials that form the sidewalls and bottom of the nonmetallic solid pillars may also include other materials known to those skilled in the art, as long as the requirements of the infrared detector pixel are met, which is not limited herein.

In some embodiments, the material comprising the solid metal posts comprises at least one of aluminum (Al), copper (Cu), or tungsten (W).

The solid metal column is formed by adopting at least one of the three metals of aluminum (Al), copper (Cu) or tungsten (W), so that the mechanical property of the solid metal column is met, stable support is realized, and meanwhile, the resistance of the solid metal column is reduced, thereby reducing electric signal loss and improving the detection performance of the infrared detector; in addition, the preparation of the solid metal column by adopting the CMOS technology is facilitated, and the technology integration requirement is met.

In other embodiments, the material of the solid metal column may be other materials, which may meet the process requirements and performance requirements of the infrared detector pixel, and is not limited herein.

In some embodiments, with continued reference to fig. 1 and 3, the dimensions of the pillars that correspondingly support the same infrared detector pixel 10 are all the same.

The corresponding columns can be formed by adopting the same process conditions, process parameters and the like, the process difficulty is low, the yield is high, and the cost is reduced.

In some embodiments, with continued reference to any of fig. 4-6, the size of the columns that are shared is greater than the size of the columns that are not shared.

The shared pillar needs to support at least two infrared detector pixels at the same time, the non-shared pillar only needs to support one infrared detector pixel, the size of the shared pillar is larger than that of the non-shared pillar through the arrangement, the shared pillar can be ensured to have larger mechanical strength, and the at least two infrared detector pixels sharing the pillar are sufficiently supported, so that the infrared detector is ensured to have higher structural stability.

It is understood that the dimensions of the pillars may be characterized by physical quantities such as the cross-sectional width, cross-sectional area, or volume of the pillars, and are not limited herein.

In some embodiments, to increase the mechanical strength of the columns being shared, additional support structures may also be added to them to ensure effective support. Alternatively, the auxiliary support layer may be coated on the outer side of the shared column, or may be implemented in other ways known to those skilled in the art, which are not limited herein.

In some embodiments, each infrared detector pixel 10 is supported by four columnar structures 22.

The arrangement is favorable for improving the support stability, so that the overall structural stability of the infrared detector is improved.

In some embodiments, each infrared detector pixel 10 is supported by two columnar structures 22.

By this arrangement, the space occupied by the columnar structure 22 can be further reduced, thereby being beneficial to improving the duty ratio of the infrared detector.

In some embodiments, with continued reference to any of fig. 7-12, the reinforcing structure 24 is disposed on a side of the beam structure 2302 facing away from the columnar structure 22.

In the structure of the infrared detector pixel, the reinforcing structure 24 is located above the columnar structure 22, which is equivalent to adding a cover plate at the position of the beam structure 2302 corresponding to the columnar structure 22, and pressing the beam structure 2302 by using the weight of the reinforcing structure 24, so that the mechanical strength between the beam structure 2302 and the columnar structure 22 is enhanced, and the structural stability of the infrared detector is improved.

In some embodiments, with continued reference to fig. 13, beam structure 2302 includes hollowed out areas at locations corresponding to columnar structures 22; the reinforcing structure 24 includes a first reinforcing portion 241 and a second reinforcing portion 242 connected to each other; the first reinforcement portion 241 is embedded in the hollow area and is in contact with the columnar structure 22; the second reinforcement 242 covers the surface of the beam structure 2302 surrounding the hollowed out area facing away from the columnar structure 22.

In the structure of the infrared detector pixel, the reinforcing structure 24 corresponds to a rivet structure formed by the first reinforcing part 241 and the second reinforcing part 242; the bottom surface of the first reinforcement portion 241 contacts the top surface of the columnar structure 22, the side surface of the first reinforcement portion 241 also contacts the side surface of the hollowed out area of the beam structure 2302, and the lower surface of the second reinforcement portion 242 contacts the surface around the hollowed out area of the beam structure 2302. Therefore, the contact area between the reinforcing structure 24 and the columnar structure 22 and the contact area between the reinforcing structure 24 and the columnar structure 2302 are increased while the beam structure 2302 is pressed by the gravity of the reinforcing structure 24, so that the mechanical strength between the beam structure 2302 and the columnar structure 22 is further increased, and the structural stability of the infrared detector is improved.

In some embodiments, the material comprising reinforcing structure 24 includes at least one of a metal or a medium.

Correspondingly, the film layer structure of the reinforcing structure 24 may be a single-layer structure deposited by a medium or a metal, or may be a multi-layer structure formed by stacking two, three or more single-layer structures, which may be set based on pixel requirements of the infrared detector and CMOS process requirements, and is not limited herein.

In some embodiments, the dielectric material comprising the reinforcing structure 24 includes at least one of amorphous silicon (a-Si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SiGe), amorphous carbon (a-C), silicon carbide (SiC), or aluminum oxide (Al 2O 3); the metal material constituting the reinforcement structure 24 includes at least one of aluminum (Al), copper (Cu), tungsten (W), gold (Au), platinum (Pt), chromium (Cr), nickel (Ni), titanium tungsten alloy (TiW), nickel chromium alloy (NiCr), nickel platinum alloy (NiPt), nickel silicon alloy (NiSi).

The dielectric material and the metal material are not corroded by VHF, so that the reinforcing structure 24 is not affected in the process of utilizing the VHF corrosion sacrificial layer (silicon oxide material), so that the mechanical strength of the joint between the beam structure 2302 and the columnar structure 22 can be enhanced by the reinforcing structure 24, the beam structure 2302 and the columnar structure 22 are prevented from falling off due to loose connection, and the structural stability of the infrared detector is improved.

In addition, when the reinforcing structure 24 is made of or contains a metal material and is directly in contact with the metal or columnar structure 22 in the beam structure 2302, the reinforcing structure 24 can be used to enhance the electrical performance, ensure the electrical connection to be intact, reduce the contact resistance, and improve the detection performance.

In other embodiments, the material of the reinforcing structure 24 may be other materials known to those skilled in the art, so long as the requirements of the infrared detector pixel and the CMOS process requirements are satisfied, which is not limited herein.

In some embodiments, with continued reference to fig. 14, the reinforcing structure 24 surrounds the sides of the adjoining columnar structures 22 and the sides of the beam structure 2302.

The reinforcing structure 24 is connected with the side surface of the beam structure 2302 and the side surface of the columnar structure 22 at the same time, and is used for assisting in connecting the beam structure 2302 and the columnar structure 22, so that good mechanical strength between the beam structure 2302 and the columnar structure 22 is ensured, and further structural stability of the infrared detector is improved.

Illustratively, the reinforcement structure 24 surrounds a portion of the sides of the adjoining columnar structures 22 and a portion of the sides of the beam structure 2302, or the reinforcement structure 24 surrounds a complete side of the adjoining columnar structures 22 and a complete side of the beam structure 2302, may be set based on the requirements of the infrared detector pixel and the CMOS process requirements, and is not limited herein.

In some embodiments, with continued reference to fig. 14, the reinforcing structures 24 extend from the beam structures 2302 along the sides of the columnar structures 22 toward the reflective layer 21.

In the pixel structure of the infrared detector, the reinforcing structure 24 and the beam structure 2302 together form a hat-shaped structure, and the hat-shaped structure is wrapped on the top and the side surface of the columnar structure 22, so as to improve the mechanical strength of the joint between the beam structure 2302 and the columnar structure 22 and improve the structural stability of the infrared detector.

In some embodiments, the reinforcement structure 24 and the beam structure 2302 may be formed using the same material in the same process step; correspondingly, the preparation process of the pixel of the existing infrared detector is different from that of the pixel of the existing infrared detector in that: in the process of imaging the infrared converting structure 23, the mask hollowed-out area adopted leaves a position corresponding to the reinforcing structure 24 relative to the prior art.

Therefore, the process steps of the infrared detector pixel can be simplified, and the process difficulty is reduced.

In other embodiments, based on fig. 14, the reinforcing structure 24 is embedded down into the film layer that originally surrounds the columnar structure 22.

By the arrangement, the bottom of the reinforcing structure 24 can be embedded between the columnar structure 22 and the film layer surrounding the columnar structure 22, so that the stability of the reinforcing structure 24 is better; and further, the connection stability between the beam structure 2302 and the columnar structure 22 can be enhanced, and the structural stability of the infrared detector can be improved.

In some embodiments, the overall height of columnar structures 22 is greater than or equal to 1.5 microns and less than or equal to 2.5 microns.

The total height of the columnar structure 22 is the height of the columnar structure in the direction perpendicular to the plane of the reflecting plate 212, which is the stacking height of each layer of columns, and may be referred to as the axial height of the columnar structure 22, and may be the supporting height of the columnar structure 22, and may be the distance between two parallel planes of the resonant cavity of the infrared detector pixel, that is, the distance between the reflecting surface of the reflecting plate 212 and the absorbing surface of the infrared converting structure 23.

Based on this, by setting the total height of the columnar structure 22 to be greater than or equal to 1.5 μm, on the one hand, the implementation by using a CMOS process is facilitated, and the process difficulty is reduced; on the other hand, the distance requirement between the parallel planes of the resonant cavity can be met, the infrared absorption efficiency is improved, and the detection sensitivity is improved. Meanwhile, by setting the total height of the columnar structure 22 to be less than or equal to 2.5 micrometers, the total height of the columnar structure 22 can not be too high, so that the problem of poor stability caused by too high columnar structure 22 is avoided, namely the stability of the structure is improved; meanwhile, the size of the infrared detector pixels and the size of the infrared detector in the height direction of the infrared detector are reduced, and the light and thin and miniaturized design of the infrared detector is realized.

Illustratively, the overall height of columnar structures 22 may be 1.5 microns, 1.8 microns, 2.0 microns, 2.1 microns, 2.4 microns, 2.5 microns, or other height values, which may be set based on the performance requirements of the infrared detector as well as the CMOS process requirements, without limitation.

In some embodiments, the unidirectional width of the cross section of the side of columnar structure 22 connecting infrared converting structure 23 is greater than or equal to 0.5 microns and less than or equal to 3 microns; alternatively, the width may be less than or equal to 1 micron.

By the arrangement, the columnar structure 22 can be used for meeting stable support, and the size of the columnar structure 22 on the plane where the reflecting plate 212 is positioned can be reduced, so that smaller chip area under the same array pixels can be realized, and chip miniaturization can be realized; in addition, the effective area ratio of the reflecting plate 212 and the corresponding infrared conversion structure 23 is improved, the signal intensity is enhanced, and the detection performance is improved.

Illustratively, when the uppermost upright is circular in cross-section, its diameter is less than or equal to 3 microns; when the section of the uppermost upright post is square, the side length of the uppermost upright post is less than or equal to 3 micrometers; when the section of the uppermost upright post is polygonal, the diagonal length is less than or equal to 3 micrometers; when the section of the uppermost upright post is in a long strip shape, the length of the long side is less than or equal to 3 micrometers.

Illustratively, the uppermost upright cross-sectional maximum unidirectional width may be 3 microns, 2.5 microns, 2 microns, 1 micron, 0.8 microns, or other width values, which may be set based on the requirements of the infrared detector, without limitation.

In some embodiments, to meet other requirements of the infrared detector, the maximum unidirectional width of the cross section of the uppermost column may also be set to be greater than 3 microns, which is not limited herein.

In some embodiments, with continued reference to fig. 15, the CMOS infrared sensing structure 2 may further include an adhesion layer 240, the adhesion layer 240 covering at least a bottom surface of the pillar structures 22 that contacts the support base 211.

Wherein the adhesive layer 240 may be used to enhance the connection between the columnar structure 22 and the support base 211, as well as between the adjacent layer of columns; the connection performance can comprise mechanical connection performance of the enhancer, structural stability is improved, electrical connection performance of the enhancer is also improved, contact resistance is reduced, loss in the electric signal transmission process is reduced, and detection performance is improved.

For example, the adhesive layer 240 may be disposed only between the columnar structure 22 and the support base 211, and also between two adjacent columns.

In some embodiments, the material constituting the adhesion layer 2400 includes at least one of titanium (Ti), titanium nitride (TiN), tantalum (Ta), or tantalum nitride (TaN).

Thus, the adhesion layer 240 is formed by adopting at least one of the four conductive materials of titanium (Ti), titanium nitride (TiN), tantalum (Ta) or tantalum nitride (TaN), so that the mechanical and electrical connection performance between the support base 211 and the columnar structure 22 and the mechanical and electrical connection performance between two adjacent columns can be enhanced by utilizing the adhesion layer 240; meanwhile, the preparation of the adhesive layer 240 by adopting the CMOS technology is facilitated, and the technology integration requirement is met.

Illustratively, the adhesive layer 240 may be provided in a single-layer structure, a double-layer structure, or a more-layer structure, may be formed of a single material, or may be formed of two or more materials, and may be provided based on the requirements of the infrared detector and its pixels, which are not limited herein.

In other embodiments, the material of the adhesion layer 240 may be other materials, which may meet the process requirements and performance requirements of the infrared detector pixel, which is not limited herein.

In some embodiments, the bottom of the columnar structure 22 may be embedded within the support pedestal 211, i.e., the lower portion of the side of the columnar structure 22 below the upper surface of the support pedestal 211 contacts the recessed side of the support pedestal 211.

Thus, the columnar structure 22 can be fixed by utilizing the concave of the supporting base 211, so that the mechanical strength is enhanced, and the structural stability is improved; meanwhile, the contact area between the columnar structure 22 and the supporting base 211 is increased, the electrical connection between the columnar structure 22 and the supporting base 211 is increased, the contact resistance is reduced, the influence of a transmission path on an electric signal is reduced, and the detection performance is improved.

In some embodiments, with continued reference to FIG. 15, in the case where the posts are solid metal posts or non-metal solid posts (not shown), the infrared detector pixel further includes a dielectric layer 250; dielectric layer 250 covers the sides of the pillars.

The dielectric layer 250 wraps the outer side of the upright post 22, and can play a role in electrical insulation, so as to slow down performance degradation of the upright post 22, thereby being beneficial to prolonging the service life of the infrared detector. Meanwhile, the dielectric layer 250 can serve as an auxiliary supporting structure of the upright post 22 and plays a role of supporting the infrared conversion structure 23 together with the upright post 22, so that the structural stability is further enhanced. Illustratively, the width of the dielectric layer 250 along the axial direction of the stud 22 may be the same as the height of the stud 22.

In some embodiments, the material comprising dielectric layer 250 includes at least one of (Si), germanium (Ge), amorphous silicon (a-Si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SiGe), amorphous carbon (a-C), silicon carbide (SiC), or aluminum oxide (Al 2O 3).

Wherein, none of the materials is corroded by VHF, so that the dielectric layer 250 is not corroded when the sacrificial layer is taken out by VHF corrosion in the subsequent process step; meanwhile, the mechanical strength of the joint can be enhanced, and the connection between the upper structure (comprising the infrared conversion structure 23 and other layers of upright posts) and the upright posts is not firm so as to prevent the falling off, thereby enhancing the structural stability.

In some embodiments, fig. 17 is a schematic cross-sectional structure of yet another infrared detector of an embodiment of the disclosure. Referring to fig. 17, the infrared detector unit further includes a dielectric protective layer 245; the dielectric protection layer 245 covers the surface of the non-supporting columnar structure 22 of the reflective layer 21; the bottom of the columnar structure 22 is embedded in the dielectric protection layer 245.

By adopting the arrangement, the bottom of the columnar structure 22 can be coated by the medium protection layer 245, so that the mechanical stability of the columnar structure 22 is improved, and therefore, the better connection performance between the columnar structure 22 and the support base 211 as well as between the columnar structure 22 and the infrared conversion structure 23 is ensured, and the structural stability is improved; meanwhile, the dielectric protection layer 245 wrapping the columnar structure 22 can also reduce the contact between the columnar structure 22 and the external environment, reduce the contact resistance between the columnar structure 22 and the external environment, further reduce the noise of the infrared detector pixels, improve the detection sensitivity of the infrared detector and improve the detection performance of the infrared detector.

In some embodiments, infrared detector pixel 10 also includes etch stop layer 25; the etching stopper 25 covers at least the corner positions of the dielectric protection layer 245.

By the arrangement, the dielectric protection layer 245 can be protected by the etching barrier layer 25, the influence of the process of removing the sacrificial layer on the dielectric protection layer 245 is weakened, the dielectric protection layer 245 can effectively protect and support the columnar structure 22, and therefore the structural stability of the infrared detector is improved.

In some embodiments, the material comprising dielectric protective layer 245 includes at least one of silicon (Si), germanium (Ge), amorphous silicon (a-Si), amorphous germanium (a-Ge), silicon germanium (SiGe), or amorphous silicon germanium (a-SiGe).

The materials such as silicon (Si), germanium (Ge), amorphous silicon (a-Si), amorphous germanium (a-Ge), silicon germanium (SiGe), amorphous silicon germanium (a-SiGe) and the like have good transmittance to infrared light, and the reflection of the infrared light by the reflective layer is not affected basically, so that the material of the dielectric protection layer 245 is at least one of the materials, the stability of the columnar structure 22 is improved by using the dielectric protection layer 245, and meanwhile, the influence of the material of the dielectric protection layer 245 on the reflection process of the resonant cavity can be avoided, and the influence of the dielectric protection layer 245 on the detection sensitivity of the CMOS infrared sensing structure is avoided.

In addition, when the material constituting the dielectric protection layer 245 includes at least one of silicon (Si), germanium (Ge), amorphous silicon (a-Si), amorphous germanium (a-Ge), silicon germanium (SiGe), or amorphous silicon germanium (a-SiGe), the dielectric protection layer 245 is formed to occupy a portion of the space of the resonator, so that the thickness of the sacrificial layer for forming the resonator can be reduced, thereby reducing the difficulty of releasing the sacrificial layer corresponding to the formation of the resonator.

In some embodiments, with continued reference to fig. 17, etch stop layer 25 includes side layer 252 disposed adjacent to planar layer 251, planar layer 251 being disposed in a ring shape, side layer 252 being disposed in a barrel shape; the side layer 252 of the etch stop layer 25 covers the side of the dielectric protection layer 245 facing the columnar structure 22, and the planar layer 251 of the etch stop layer 25 surrounds the columnar structure 22 and covers the surface of the dielectric protection layer 245 adjacent to the side.

The side layer 252 is disposed between the columnar structure 22 and the dielectric protection layer 245, so that the dielectric protection layer 245 can be protected from VHF corrosion; on the other hand, the columnar structure 22 can be supported in an auxiliary manner, and the supporting performance of the columnar structure 22 is improved. Illustratively, the barrel-like structure of the side layer 252 may be specifically configured as a barrel, square barrel, or other shaped barrel, and may be configured based on the side shape of the columnar structure 22, as not limited herein.

Wherein planar layer 251 is disposed adjacent to side layer 252 to form etch stop layer 25 covering at least the angular locations of dielectric protective layer 245. Illustratively, the annular structure of the planar layer 251 may be specifically configured as a circular ring, a Fang Kongyuan ring, a square ring, or other shapes, and may be configured based on the shape of the upper surface of the columnar structure 22 and the protection requirement of the dielectric protection layer 245, which is not limited herein.

In some embodiments, a corresponding dielectric protective layer 245 may be provided for each layer of pillars; the dielectric protection layer 245 is at least one layer, and correspondingly, the etching barrier layer 25 is at least one layer; the etching stopper 25 is disposed at least at the corner of the uppermost dielectric protection layer 245.

Where the dielectric protection layer 245 is two or more layers, the protection is achieved by providing a corresponding etching barrier layer 25 to a portion of the dielectric protection layers 245, for example, only the uppermost dielectric protection layer 245, only the lowermost dielectric protection layer 245, or one or more other dielectric protection layers 245, which are not limited herein.

In some embodiments, when the etch stop layer 25 is at least two layers, the shape and size of the etch stop layer 25 at each of the different layers are the same.

Thus, the same technological process and technological parameters can be adopted to form the etching barrier layers 25 of different layers, so that the technological difficulty is low and the cost is low; meanwhile, the etching barrier layers 25 positioned on different layers have more uniform influence on the infrared detector pixels and the performances (including mechanical performances and electrical performances) of the infrared detector comprising the infrared detector pixels, and are beneficial to ensuring better detection performances.

In some embodiments, when the etch stop layer 25 is at least two layers, the size of the etch stop layer 25 located at the upper layer is different from the size of the etch stop layer 25 located at the lower layer.

Illustratively, the size of the etching barrier layer 25 on the upper layer is larger than that of the etching barrier layer 25 on the lower layer, or the size of the etching barrier layer 25 on the upper layer is smaller than that of the etching barrier layer 25 on the lower layer, so that the etching path is changed, the etching rate of the dielectric protection layer 245 at the position near the columnar structure 22 is reduced, the effective protection and support of the dielectric protection layer 245 on the columnar structure 22 are realized, and the structural stability of the infrared detector is improved.

In some embodiments, FIG. 18 is a top view of one corrosion barrier structure in an infrared detector pixel of an embodiment of the disclosure, and FIG. 19 is a top view of another corrosion barrier structure in an infrared detector pixel of an embodiment of the disclosure. Referring to fig. 18 or 19, the planar layers include separately disposed block structures (block structures of two different planar layers are shown at 2511 and 2512, respectively); the projections of the block structures of the planar layers onto the reflective layer 21 in the axial direction of the columnar structures 22 overlap and surround the columnar structures 22.

Wherein, the projections of the block structures of each layer of flat layer on the reflecting layer 21 along the axial direction of the columnar structure 22 overlap, that is, the vertical projections of the block structures of each layer of flat layer on the plane of the reflecting layer 21 along the longitudinal direction overlap, and the block structures are spliced together into an annular structure, and the annular structure surrounds the columnar structure 22.

Therefore, in the two adjacent layers of block structures, the edge positions of the two adjacent block structures at the upper layer and the lower layer are staggered, so that the corrosion path of the VHF is changed, the corrosion rate of the VHF at the corresponding position is reduced, and the protection of the dielectric protection layer 245 is realized.

Illustratively, referring to FIG. 18, the block structure may employ a fan blade design; alternatively, referring to FIG. 19, the block structure may be of a trapezoidal design; in other embodiments, the block structure may take other shapes, not limited herein.

Illustratively, each layer of block structure is shown in fig. 18 and 19 to adopt the same shape, but is not limited to the infrared detector pixel provided by the embodiments of the present disclosure. In other embodiments, the block structures located in different layers may be designed in different shapes, which is not limited herein.

In some embodiments, the material comprising etch stop layer 25 comprises at least one of a metallic material or a dielectric material; the metal material includes at least one of aluminum (Al), copper (Cu), tungsten (W), or titanium tungsten alloy (TiW); the dielectric material comprises amorphous silicon (a-Si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SiGe), amorphous carbon (a-C), silicon carbide (SiC) or aluminum oxide (Al) ₂ O ₃ ) At least one of them.

The above materials are not corroded by VHF, so that the etching barrier layer 25 is not corroded when the sacrificial layer is removed by VHF corrosion in the subsequent process steps, and the dielectric protection layer 245 covered by the etching barrier layer 25 is not corroded, thereby protecting the dielectric protection layer 245; meanwhile, at least one of the above materials forms the etching barrier layer 25, so that the mechanical property of the etching barrier layer 25 is better, and part of the etching barrier layer 25 is positioned between the columnar structure 22 and the dielectric protection layer 245, so that the auxiliary supporting effect can be achieved, the supporting stability of the columnar structure 22 is improved, and the structural stability of the infrared detector is enhanced.

In other embodiments, the materials that make up the dielectric protection layer 245 and the etching barrier layer 25 may also include other materials known to those skilled in the art, as long as the requirements of the infrared detector pixel are satisfied, which is not limited herein.

In some embodiments, the infrared detector type may be an amorphous silicon detector, a titanium oxide detector, a vanadium oxide detector, or the like, i.e., the material constituting the thermosensitive layer may include at least one of amorphous silicon, titanium oxide, or vanadium oxide, to which embodiments of the present disclosure are not limited.

In some embodiments, fig. 20 is a schematic structural diagram of a CMOS measurement circuitry provided in an embodiment of the disclosure. Referring to fig. 1 and 20, the cmos measurement circuitry 1 includes a bias voltage generating circuit 7, a column-level analog front-end circuit 8, and a row-level circuit 9, an input terminal of the bias voltage generating circuit 7 is connected to an output terminal of the row-level circuit 9, an input terminal of the column-level analog front-end circuit 8 is connected to an output terminal of the bias voltage generating circuit 7, the row-level circuit 9 includes a row-level mirror image pixel Rsm and a row selection switch K1, and the column-level analog front-end circuit 8 includes a blind pixel RD; the row-level circuit 9 is distributed in each pixel, selects a signal to be processed according to a row strobe signal of the time sequence generating circuit, and outputs a current signal to the column-level analog front-end circuit 8 under the action of the bias voltage generating circuit 7 so as to perform current-voltage conversion output; when the row stage circuit 9 is controlled by the row selection switch K1 and is turned on, the third bias voltage VRsm is outputted to the bias voltage generating circuit 7, the bias voltage generating circuit 7 outputs the first bias voltage V1 and the second bias voltage V2 according to the inputted constant voltage and the third bias voltage VRsm, the column stage analog front end circuit 8 obtains two paths of currents according to the first bias voltage V1 and the second bias voltage V2, and performs transimpedance amplification on the difference between the two paths of generated currents and outputs the difference as an output voltage.

Specifically, the row stage circuit 9 includes a row stage mirror pixel Rsm and a row select switch K1, and the row stage circuit 9 is configured to generate the third bias voltage VRsm according to the gate state of the row select switch K1. Illustratively, the row-level image element Rsm may be subjected to shading treatment, so that the row-level image element Rsm is subjected to fixed radiation of a shading sheet with a temperature equal to that of the substrate, the row selection switch K1 may be implemented by a transistor, the row selection switch K1 is closed, and the connection of the row-level image element Rsm and the bias voltage generating circuit 7, that is, the row-level circuit 9 outputs the third bias voltage VRsm to the bias voltage generating circuit 7 when being gated under the control of the row selection switch K1. The bias voltage generating circuit 7 may include a first bias voltage generating circuit 71 and a second bias voltage generating circuit 72, the first bias voltage generating circuit 71 being configured to generate the first bias voltage V1 based on an input constant voltage, which may be, for example, a positive power supply signal having a constant voltage. The second bias voltage generating circuit 72 may include a bias voltage control sub-circuit 721 and a plurality of gate driving sub-circuits 722, the bias voltage control sub-circuit 721 for controlling the gate driving sub-circuits 722 to generate the corresponding second bias voltages V according to the third bias voltages VRsm, respectively.

The column-level analog front-end circuit 8 includes a plurality of column control sub-circuits 81, the column control sub-circuits 81 being disposed in correspondence with the gate driving sub-circuits 722, and for example, the column control sub-circuits 81 may be disposed in one-to-one correspondence with the gate driving sub-circuits 722, and the gate driving sub-circuits 722 are configured to supply the second bias voltage V2 to the corresponding column control sub-circuits 81 according to their own gate states. Illustratively, the gate drive subcircuit 722 may be configured to provide the second bias voltage V2 to the corresponding column control subcircuit 81 when the gate drive subcircuit 722 is gated; when the gate driving sub-circuit 722 is not gated, the gate driving sub-circuit 722 stops supplying the second bias voltage V2 to the corresponding column control sub-circuit 81.

The column-level analog front-end circuit 8 comprises an effective pixel RS and a blind pixel RD, and the column control sub-circuit is used for generating a first current I1 according to a first bias voltage V1 and the blind pixel RD, generating a second current I2 according to a second bias voltage V2 and the effective pixel RS, performing transimpedance amplification on a difference value between the first current I1 and the second current I2, and outputting the difference value, wherein the temperature drift quantity of the row-level mirror image pixel Rsm is the same as that of the effective pixel RS under the same ambient temperature.

Illustratively, the row-level image pixels Rsm are thermally insulated from the CMOS measurement circuitry 1, and are subjected to shading processing, and are subjected to fixed radiation from a shading sheet having a temperature equal to the substrate temperature. The absorber plate 10 of the active pixel RS is thermally insulated from the CMOS measurement circuitry 1 and the active pixel RS receives external radiation. The absorption plates 10 of the row-level mirror image pixels Rsm and the effective pixels RS are thermally insulated from the CMOS measurement circuitry 1, so that both the row-level mirror image pixels Rsm and the effective pixels RS have self-heating effects.

When the corresponding row-level image pixels Rsm are gated through the row selection switch K1, resistance changes are generated by joule heat of the row-level image pixels Rsm and the effective pixels RS, but when the row-level image pixels Rsm and the effective pixels RS are subjected to the same fixed radiation, the resistance of the row-level image pixels Rsm and the effective pixels RS are the same, the temperature coefficients of the row-level image pixels Rsm and the effective pixels RS are the same, the temperature drift amounts of the row-level image pixels Rsm and the effective pixels RS at the same ambient temperature are the same, and the changes of the row-level image pixels Rsm and the effective pixels RS are synchronous, so that the stable output of the reading circuit is realized by utilizing the characteristic that the temperature drift amounts of the row-level image pixels Rsm and the effective pixels RS are the same at the same ambient temperature.

In addition, by setting the second bias voltage generating circuit 7 to include the bias voltage control sub-circuit 721 and the gate driving sub-circuits 722, the bias voltage control sub-circuit 721 is configured to control the gate driving sub-circuits 722 to generate the corresponding second bias voltages V2 according to the row control signals, so that each row of pixels has one way to drive the whole row of pixels of the row individually, which reduces the requirement on the second bias voltages V2, i.e. improves the driving capability of the bias voltage generating circuit 7, and is beneficial to driving a larger-scale infrared detector pixel array by using the readout circuit. In addition, the specific details of the CMOS measurement circuitry 1 are well known to those skilled in the art, and will not be described herein.

Fig. 21 is a schematic cross-sectional view of another infrared detector according to an embodiment of the disclosure. As shown in fig. 21, on the basis of the above embodiment, the CMOS fabrication process of the CMOS measurement circuitry 1 may also include a metal interconnection process and a via process, the CMOS measurement circuitry 1 includes a metal interconnection layer 101, a dielectric layer 102 and a silicon substrate 103 at the bottom, which are disposed at intervals, the upper and lower metal interconnection layers 101 are electrically connected through vias 104,

referring to fig. 1 to 21, the CMOS infrared sensing structure 2 includes a resonant cavity formed by a reflective layer 21 and a heat-sensitive dielectric layer, a suspended micro-bridge structure for controlling heat transfer, and a columnar structure 22 having an electrical connection and supporting function, and the CMOS measurement circuitry 1 is configured to measure and process array resistance values formed by one or more CMOS infrared sensing structures 2, and convert infrared signals into image electric signals.

Specifically, the resonant cavity may be formed by, for example, a cavity between the reflective layer 21 and the absorbing plate 2301, where infrared light is reflected back and forth through the absorbing plate 2301 to improve the detection sensitivity of the infrared detector, and due to the arrangement of the columnar structure 22, the beam structure 2302 and the absorbing plate 2301 form a suspended micro-bridge structure for controlling heat transfer, and the columnar structure 22 is electrically connected to the support base 211 and the corresponding beam structure 2302, and is also used for supporting the infrared conversion structure 23 located on the columnar structure 22.

Alternatively, the CMOS infrared sensing structure 2 may be prepared on top of or on top of the metal interconnect layer of the CMOS measurement circuitry 1. Specifically, the metal interconnection layer of the CMOS measurement circuitry 1 may be the top metal layer in the CMOS measurement circuitry 1, and in conjunction with fig. 21, the CMOS infrared sensing structure 2 may be prepared on the upper layer of the metal interconnection layer of the CMOS measurement circuitry 1, where the CMOS infrared sensing structure 2 is electrically connected to the CMOS measurement circuitry 1 through the support base 211 located on the upper layer of the metal interconnection layer of the CMOS measurement circuitry 1, so as to implement transmission of the electrical signal converted by the infrared signal to the CMOS measurement circuitry 1.

Fig. 22 is a schematic cross-sectional structure of another infrared detector provided in the embodiment of the present disclosure, as shown in fig. 22, the CMOS infrared sensing structure 2 may be prepared by the same layer of the metal interconnection layer disposed in the CMOS measurement circuit system 1, that is, the CMOS measurement circuit system 1 and the CMOS infrared sensing structure 2 are disposed in the same layer, as shown in fig. 22, the CMOS infrared sensing structure 2 may be disposed on one side of the CMOS measurement circuit system 1, and the top of the CMOS measurement circuit system 1 may also be provided with a sealing release isolation layer 11 to protect the CMOS measurement circuit system 1.

Optionally, the CMOS infrared sensing structure 2 includes an absorbing plate 2301, a beam structure 2302, a reflective layer 21 and a columnar structure 22, the absorbing plate 2301 includes a material for absorbing an infrared target signal and converting the infrared target signal into an electric signal, the absorbing plate 2301 includes a metal interconnection layer and at least one heat-sensitive dielectric layer, the material constituting the heat-sensitive dielectric layer includes at least one of amorphous silicon, amorphous germanium silicon, titanium oxide, vanadium oxide or vanadium titanium oxide, the metal interconnection layer in the absorbing plate 2301 is an electrode layer in the absorbing plate 2301 for transmitting the electric signal converted by the infrared signal, the heat-sensitive dielectric layer includes at least one of a heat-sensitive layer, and may further include a supporting layer and a passivation layer, the material constituting the heat-sensitive dielectric layer includes at least one of amorphous silicon, amorphous germanium silicon, titanium oxide, vanadium oxide or vanadium titanium oxide, i.e., the material constituting the heat-sensitive layer includes at least one of amorphous silicon, amorphous germanium, titanium oxide, vanadium oxide or vanadium titanium oxide.

The beam structure 2302 and the columnar structure 22 are used for transmitting electrical signals and for supporting and connecting the absorber plate 2301, the electrode layer in the absorber plate 2301 comprises two patterned electrode structures, the two patterned electrode structures output positive electrical signals and ground electrical signals respectively, the positive electrical signals and the ground electrical signals are transmitted to a support base electrically connected with the columnar structure 22 through different beam structures 2302 and different columnar structures 22, and further transmitted to the CMOS measurement circuitry 1, the beam structure 2302 comprises a metal interconnection layer and at least one dielectric layer, the metal interconnection layer in the beam structure 2302 is the electrode layer in the beam structure 2302, the electrode layer in the beam structure 2302 is electrically connected with the electrode layer in the absorber plate 2301, and the dielectric layer in the beam structure 2302 may comprise a support layer and a passivation layer.

The pillar structure 22 connects the beam structure 2302 and the CMOS measurement circuitry 1 by using a metal interconnection process and a via process, the upper portion of the pillar structure 22 needs to be electrically connected to the electrode layer in the beam structure 2302 through a via penetrating the support layer in the beam structure 2302, and the lower portion of the pillar structure 22 needs to be electrically connected to the corresponding support base 211 through a via penetrating the dielectric layer on the support base 211. The reflecting plate 212 is used for reflecting the infrared signal and forming a resonant cavity with the heat sensitive medium layer, that is, the reflecting plate 212 is used for reflecting the infrared signal and forming a resonant cavity with the heat sensitive layer in the heat sensitive medium layer, and the reflecting layer 21 comprises at least one metal interconnection layer, wherein the metal interconnection layer is used for forming the supporting base 211 and also used for forming the reflecting plate 212.

Alternatively, at least two ends of the beam structure 2302 and the absorber plate 2301 may be electrically connected, the CMOS infrared sensing structure 2 includes at least two pillar structures 22 and at least two support pedestals 211, and the electrode layer includes at least two electrode terminals. Specifically, as shown in fig. 1, beam structures 2302 are electrically connected to both ends of the absorber plate 2301, each beam structure 2302 is electrically connected to one end of the absorber plate 2301, the CMOS infrared sensing structure 2 includes two columnar structures 22, the electrode layer includes at least two electrode terminals, at least part of the electrode terminals transmit positive electric signals, at least part of the electrode terminals transmit negative electric signals, and the positive electric signals are transmitted to the support base 211 through the corresponding beam structures 2302 and the columnar structures 22.

Fig. 23 is a schematic perspective view of another infrared detector according to an embodiment of the disclosure. As shown in fig. 23, beam structures 2302 may be electrically connected to four ends of the absorber plate 2301, each beam structure 2302 being electrically connected to two ends of the absorber plate 2301, and the CMOS infrared sensing structure 2 includes four pillar structures 22, and one beam structure 2302 connects two pillar structures 22. Note that, in the embodiment of the present disclosure, the number of connection ends of the beam structure 2302 and the absorber plate 2301 is not particularly limited, so that it is sufficient to ensure that the beam structure 2302 and the electrode end are respectively present, and the beam structure 2302 is used for transmitting an electrical signal output by the corresponding electrode end.

Optionally, the infrared detector may be configured based on a 3nm, 7nm, 10nm, 14nm, 22nm, 28nm, 32nm, 45nm, 65nm, 90nm, 130nm, 150nm, 180nm, 250nm, or 350nm CMOS process, the dimensions characterizing process nodes of the integrated circuit, i.e., characterizing feature sizes during processing of the integrated circuit.

Alternatively, a metal wiring material constituting the metal interconnection layer in the infrared detector may be provided to include at least one of aluminum, copper, tungsten, titanium, nickel, chromium, platinum, silver, ruthenium, or cobalt, and a material constituting the reflection layer may be provided to include at least one of aluminum, copper, tungsten, titanium, nickel, chromium, platinum, silver, ruthenium, or cobalt, for example. In addition, the CMOS measurement circuitry 1 and the CMOS infrared sensing structure 2 are both prepared by using CMOS processes, and the CMOS infrared sensing structure 2 is directly prepared on the CMOS measurement circuitry 1, so that the radial side length of the columnar structure 22 is greater than or equal to 0.5um and less than or equal to 3um, the width of the beam structure 2302, that is, the width of a single line in the beam structure 2302 is less than or equal to 0.3um, the height of the resonant cavity is greater than or equal to 1.5um and less than or equal to 2.5um, and the side length of a single pixel of the CMOS infrared sensing structure 2 is greater than or equal to 6um and less than or equal to 17um.

It should be noted that in this document, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely a specific embodiment of the disclosure to enable one skilled in the art to understand or practice the disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown and described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An infrared detector based on a CMOS process, comprising:

infrared detector pixels arranged in an array; the infrared detector pixel comprises a CMOS measurement circuit system and a CMOS infrared sensing structure positioned on the CMOS measurement circuit system, wherein the CMOS measurement circuit system and the CMOS infrared sensing structure are prepared by adopting a CMOS process, and the CMOS infrared sensing structure is directly prepared on the CMOS measurement circuit system;

at least two infrared detector pixels share at least one columnar structure;

the infrared detector pixel also comprises a reinforcing structure; the reinforcement structure is used for enhancing the connection stability between the columnar structure and the infrared conversion structure;

the infrared detector pixel also comprises an etching barrier layer and a dielectric protective layer, wherein the dielectric protective layer is positioned above the reflecting layer and covers part of the surface of the reflecting layer, and the etching barrier layer at least covers the corner position of the dielectric protective layer; the etching barrier layer comprises a side layer and a plane layer which are adjacently arranged, the side layer is used for coating the dielectric protection layer and faces the side surface of the columnar structure, the plane layer is used for surrounding the columnar structure and coating the surface of the dielectric protection layer adjacent to the side surface, the number of layers of the dielectric protection layer is at least two, the number of layers of the etching barrier layer is at least two, the size of the plane layer in the upper etching barrier layer is different from the size of the plane layer in the lower etching barrier layer, the plane layer comprises a block structure which is separately arranged, projections of the block structures in each layer on the reflecting layer are overlapped and are arranged around the columnar structure, the edge positions of the two adjacent block structures in the upper layer and the lower layer are staggered, so that the VHF corrosion path is changed, the VHF corrosion rate at the corresponding position is reduced, and the etching barrier layer is not arranged at the corresponding position of the reflecting plate;

The absorber plate includes only an electrode layer and a heat sensitive layer, and the beam structure includes only an electrode layer and a heat sensitive layer; the material forming the thermosensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium and amorphous silicon germanium, the material forming the electrode layer at least comprises titanium tungsten alloy, the CMOS infrared sensing structure comprises a sacrificial layer, the sacrificial layer is used for enabling the CMOS infrared sensing structure to form a hollowed-out structure, and the material forming the sacrificial layer is silicon oxide.

2. The infrared detector as set forth in claim 1, wherein the sacrificial layer is etched using post-CMOS process;

3. The infrared detector as set forth in claim 1, wherein each of said columns is at least one of a solid metal column, a non-metal solid column or a hollow column, and wherein the material constituting the side walls of said non-metal solid column and the material constituting the side walls of said hollow column each comprise a metal;

the side wall of the hollow column is formed by combining metal and a medium, and sequentially comprises a first medium layer, a metal layer and a second medium layer along the radial direction of the hollow column;

the second dielectric layer is arranged on one side of the metal layer, which is away from the first dielectric layer;

the metal material constituting the side wall of the hollow column comprises at least one of titanium, titanium nitride, tantalum or tantalum nitride, or the metal material constituting the side wall of the hollow column comprises at least one of titanium tungsten alloy, nichrome, nickel platinum alloy, nickel silicon alloy, nickel, chromium or platinum;

the dielectric material forming the side wall of the hollow column comprises at least one of amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide or aluminum oxide;

the side wall and the bottom of the nonmetal solid column are formed by metal materials, and a space surrounded by the side wall is filled with nonmetal materials;

the nonmetallic material constituting the nonmetallic solid column includes at least one of silicon dioxide, silicon nitride, amorphous silicon, amorphous germanium, amorphous silicon germanium, amorphous carbon, silicon carbide, silicon carbonitride, or aluminum oxide;

The metal material constituting the nonmetallic solid posts includes at least one of titanium, titanium nitride, tantalum, or tantalum nitride, or at least one of titanium tungsten alloy, nichrome, nickel platinum alloy, nickel silicon alloy, nickel, chromium, or platinum;

the solid metal posts are comprised of a material comprising at least one of aluminum, copper, or tungsten.

4. The infrared detector of claim 1, wherein each layer of columns in the columnar structure is a same type of column; and/or

The upright posts positioned on the same layer are all of the same type.

5. The infrared detector according to claim 1, wherein the number of layers of the column in the columnar structure is n, n is equal to or greater than 2, and is a positive integer; wherein the method comprises the steps of

The n layers of upright posts are solid metal posts;

6. The infrared detector as set forth in claim 1, wherein the same columnar structure is shared by at least two adjacent infrared detector pixels;

The infrared detector pixels are arranged in rows and columns;

7. The infrared detector of claim 1, wherein the columnar structure comprises a bottom layer column and a top layer column, the bottom layer column being connected between the top layer column and the support base, the top layer column being connected between the bottom layer column and the infrared conversion structure;

one bottom upright correspondingly supports at least two top uprights;

each infrared detector pixel is provided with a top column of the infrared detector pixel independently;

the bottom layer stand columns and the top layer stand columns are solid metal stand columns;

8. The infrared detector of claim 1, wherein the columnar structures that correspond to and support the same infrared detector pixel are all the same size;

alternatively, the columnar structures that are shared are larger in size than the columnar structures that are not shared.

9. The infrared detector as set forth in claim 1, wherein said reinforcing structure is disposed on a side of said beam structure facing away from said columnar structure;

the second reinforcement part covers the surface, deviating from the columnar structure, of the beam structure surrounding the hollowed-out area;

the material constituting the reinforcing structure comprises at least one of metal or medium;

the metal material constituting the reinforcing structure comprises at least one of aluminum, copper, tungsten, gold, platinum, chromium, nickel, titanium tungsten alloy, nichrome, nickel platinum alloy and nickel silicon alloy;

10. The infrared detector as set forth in claim 1, wherein said reinforcing structure surrounds adjoining sides of said columnar structure and sides of said beam structure;

the reinforcing structure extends from the beam structure to the direction of the reflecting layer along the side surface of the columnar structure;

the reinforcement structure is formed of the same material as the beam structure.

11. The infrared detector as set forth in claim 1, wherein the columnar structure has an overall height of 1.5 microns or more and 2.5 microns or less; and/or

12. The infrared detector as set forth in claim 1, further comprising an adhesion layer;

the adhesion layer at least covers the bottom surface of the columnar structure, which contacts the supporting base;

the adhesion layer is also positioned between two adjacent layers of the upright posts;

the material constituting the adhesion layer includes at least one of titanium, titanium nitride, tantalum, or tantalum nitride.

13. The infrared detector as set forth in claim 1, wherein the bottom of said columnar structure is embedded within said support base.