CN113659015A - Infrared detector, preparation method thereof and infrared detection system - Google Patents
Infrared detector, preparation method thereof and infrared detection system Download PDFInfo
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
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- H01L31/02327—Optical elements or arrangements associated with the device the optical elements being integrated or being directly associated to the device, e.g. back reflectors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
- H01L31/02002—Arrangements for conducting electric current to or from the device in operations
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
Abstract
The application provides an infrared detector, a preparation method thereof and an infrared detection system, wherein the infrared detector comprises a pixel array, each pixel in the pixel array comprises a bridge arm and a bridge floor supported on an aluminum layer through the bridge arm, the bridge floor comprises an absorption film system, and the absorption film system sequentially comprises a cavity layer, a first dielectric layer, a metal layer, a second dielectric layer, a heat-sensitive layer and a third dielectric layer in the direction away from the aluminum layer. Compared with the prior art, the infrared detector designs the pixel array which can have strong absorption in the mid-span waveband with the wavelength of 3-7 microns by adjusting the absorption film system, and effectively improves the infrared radiation absorption rate in the waveband range. Therefore, the infrared detection system has high absorptivity for the detected target with the infrared wavelength of 3-7 μm. The preparation method of the infrared detector is simple in process, easy to operate, easy in raw material obtaining and capable of being widely applied to industrial production.
Description
Technical Field
The application relates to the technical field of uncooled infrared detectors, in particular to an infrared detector, a preparation method thereof and an infrared detection system.
Background
The production and living scenes of China are closely related to resources such as oil gas and the like, and the main component of the oil gas, namely methane, is easy to leak, so that once the main component of the oil gas leaks, fire, explosion and the like are caused, and serious life and property loss is caused. Meanwhile, toxic gases such as nitrogen dioxide from vehicle exhaust and factory exhaust gas damage the environment. Therefore, the method has great significance for detecting, identifying and even positioning the harmful gases.
The conventional uncooled infrared detector mainly absorbs long-wave infrared of 8-14 μm, while the absorption peak of methane is located at 3.25-3.4 μm, the absorption peak of nitrogen dioxide is located at 6.1-6.2 μm, and is not in the long-wave band range of 8-14 μm, so that it is difficult to realize high infrared radiation absorption rate to the above harmful gases. In addition, the conventional infrared detection system only utilizes the infrared characteristic absorption energy difference between gas molecules and the background during passive imaging, and the generated signal intensity is limited.
Disclosure of Invention
In view of the above problems in the prior art, an object of the present application is to provide an infrared detector, a method for manufacturing the same, and an infrared detection system, so as to improve the absorption rate of the infrared detector to a detected object.
A first aspect of the application provides an infrared detector comprising an array of pixels; each pixel in the pixel array comprises a bridge arm and a bridge floor, and the bridge floor is supported on the aluminum layer through the bridge arm; the bridge deck comprises an absorption film system, and the absorption film system sequentially comprises a cavity layer, a first medium layer, a metal layer, a second medium layer, a thermosensitive layer and a third medium layer in the direction away from the aluminum layer.
In some embodiments of the present application, the thickness of each layer in the absorbent film system is: cavity layer: 1000nm-2000nm, first dielectric layer: 50nm-70nm, metal layer: 10nm-20nm, a second dielectric layer: 60nm-90nm, thermosensitive layer: 70nm-100nm, a third dielectric layer: 110nm-150 nm.
In some embodiments of the present application, the bridge deck further comprises a plurality of pores, the pores having a diameter of 0.5 μm to 5 μm.
In some embodiments of the present application, the material of the first dielectric layer, the second dielectric layer, and the third dielectric layer is each independently selected from any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide, and silicon phosphide.
In some embodiments of the present application, the material of the metal layer is selected from any one of titanium, titanium nitride, nickel and chromium.
In some embodiments of the present application, the material of the thermosensitive layer is selected from any one of vanadium oxide and amorphous silicon.
In some embodiments of the present application, the pixel has an average absorption greater than 80% in an infrared band having a wavelength of 3 μm to 7 μm.
In some embodiments of the present application, the detection wavelength of the infrared detector is 3 μm to 7 μm.
A second aspect of the present application provides a method for manufacturing an infrared detector, which includes the following steps:
(1) forming a patterned aluminum layer on a silicon substrate, the patterned aluminum layer including a reflective layer, a first circuit electrode, and a second circuit electrode;
(2) sequentially forming a sacrificial layer and a first dielectric layer on the structure obtained in the step (1);
(3) forming a graphical metal layer, a second dielectric layer and a thermosensitive layer on the first dielectric layer;
(4) forming a first patterned dielectric layer and a sacrificial layer on the structure obtained in the step (3) to form a first via hole and a second via hole which penetrate through the first dielectric layer and the sacrificial layer, wherein the first via hole is communicated with the first circuit electrode, and the second via hole is communicated with the second circuit electrode;
(5) forming a third graphical dielectric layer on the structure obtained in the step (4) to form a third via hole, a fourth via hole, a fifth via hole and a sixth via hole, wherein the third via hole penetrates through the third dielectric layer, the third via hole corresponds to the first via hole and is communicated with the first circuit electrode, the fourth via hole corresponds to the second via hole and is communicated with the second circuit electrode, and the fifth via hole and the sixth via hole are communicated with the thermosensitive layer;
(6) forming a patterned conductive layer on the structure obtained in the step (5), wherein the patterned conductive layer comprises a first conductive electrode and a second conductive electrode; the first conductive electrode penetrates through the third through hole to be electrically connected with the first circuit electrode, and the first conductive electrode also penetrates through the fifth through hole to be electrically connected with the thermosensitive layer; the second conductive electrode penetrates through the fourth through hole to be electrically connected with the second circuit electrode, and the second conductive electrode also penetrates through the sixth through hole to be electrically connected with the thermosensitive layer;
(7) forming a fourth dielectric layer on the structure obtained in the step (6);
(8) etching the structure obtained in the step (7) to form a micro-bridge structure; and etching the sacrificial layer to form a cavity layer on the sacrificial layer, thereby obtaining the suspension micro-bridge structure.
In some embodiments of the present application, step (3) comprises:
forming a metal layer on the first dielectric layer, forming a second dielectric layer on the metal layer, forming a heat-sensitive layer on the second dielectric layer, and then sequentially etching the heat-sensitive layer, the second dielectric layer and the metal layer to pattern the heat-sensitive layer, the second dielectric layer and the metal layer.
In some embodiments of the present application, step (3) comprises:
(a) forming a metal layer on the first dielectric layer, and etching the metal layer to pattern the metal layer;
(b) forming a second dielectric layer on the structure obtained in the step (a), and etching the second dielectric layer to pattern the second dielectric layer;
(c) forming a thermosensitive layer on the structure obtained in the step (b), and etching the thermosensitive layer to pattern the thermosensitive layer.
In some embodiments of the present application, the thickness of the cavity layer is 1000nm to 2000nm, the thickness of the first dielectric layer is 50nm to 70nm, the thickness of the metal layer is 10nm to 20nm, the thickness of the second dielectric layer is 60nm to 90nm, the thickness of the thermosensitive layer is 70nm to 100nm, and the thickness of the third dielectric layer is 110nm to 150 nm.
In some embodiments of the present application, after the step (7), the fourth dielectric layer, the conductive layer, the third dielectric layer, the thermosensitive layer, the second dielectric layer, the metal layer, the first dielectric layer and the sacrificial layer may be sequentially etched to form a plurality of small holes, and the diameter of the small holes is 0.5 μm to 5 μm.
In some embodiments of the present application, the method of etching the aluminum layer, the sacrificial layer, the first dielectric layer, the metal layer, the second dielectric layer, the thermal sensitive layer, the third dielectric layer, the conductive layer, and the fourth dielectric layer includes a dry etching process.
In some embodiments of the present application, the material of the sacrificial layer is selected from polyimide.
In some embodiments of the present application, the materials of the first dielectric layer, the second dielectric layer, the third dielectric layer, and the fourth dielectric layer are each independently selected from any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide, and silicon phosphide.
In some embodiments of the present application, the material of the metal layer and the conductive layer is selected from any one of titanium, titanium nitride, nickel, and chromium.
In some embodiments of the present application, the material of the thermosensitive layer is selected from any one of vanadium oxide and amorphous silicon.
A third aspect of the present application provides an infrared detection system comprising the infrared detector of the first aspect of the present application.
In some embodiments of the present application, the infrared detection system further comprises a medium wave light source, the medium wave light source emitting light having a wavelength of 3 μm to 5 μm.
In some embodiments of the present application, the infrared detection system further comprises a narrow-band filter, the narrow-band filter is disposed between the optical window and the infrared detector, and the transmittance of the narrow-band filter in the infrared band of 3 μm to 7 μm is greater than or equal to 80%, and the transmittance in the rest ranges is less than or equal to 10%.
The application provides an infrared detector, it includes the pixel array, and every pixel in this pixel array includes bridge arm and bridge floor, and the bridge floor passes through the bridge arm to be supported on the aluminium lamination, and this bridge floor includes the absorption membrane system, and in the direction of keeping away from the aluminium lamination, the absorption membrane system includes cavity layer, first dielectric layer, metal level, second dielectric layer, temperature sensing layer and third dielectric layer in proper order. Compared with the prior art, the infrared detector obtains the pixel array with strong absorption rate in the mid-span waveband with the wavelength of 3-7 microns by adjusting the absorption film system, effectively improves the infrared radiation absorption rate in the waveband range, and can reach more than 95% at most. And the absorption film system has simple and easily obtained structure and can be compatible with the existing preparation process of the long wave detector. The infrared detector is applied to the infrared detection system, and the medium wave light source equipment is adopted to actively illuminate the detected target, so that the difference value of the radiation quantity of gas and background environment is increased, and the detection sensitivity of the infrared detection system to the detected target is improved. The narrow-band filter is further applied to the infrared detection system to limit the infrared radiation wave band entering the infrared detection system, and then the imaging sensitivity of the detected target of the corresponding wave band is effectively improved. The infrared detection system is used for detecting and imaging the detected target with the wavelength of 3-7 mu m, and can efficiently and accurately detect, identify and even locate the detected target. The preparation method of the infrared detector is simple in process, easy to operate, easy in raw material obtaining and capable of being widely applied to industrial production.
Of course, not all advantages described above need to be achieved at the same time in the practice of any one product or method of the present application.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only one embodiment of the present application, and other embodiments can be obtained by those skilled in the art according to the drawings.
FIG. 1 is a top view of a pixel structure according to some embodiments of the present application;
FIG. 2 is a cross-sectional view of a pixel structure according to some embodiments of the present application;
FIG. 3 is a schematic illustration of the absorption of a pixel as a function of wavelength in an infrared detector according to some embodiments of the present application;
FIG. 4 is an absorption spectrum of methane;
FIG. 5 is an absorption spectrum of nitrogen dioxide;
FIG. 6 is a top view of a pixel structure according to further embodiments of the present application;
FIGS. 7 a-7 l are schematic cross-sectional views of an infrared detector according to some embodiments of the present disclosure, illustrating various steps of manufacturing the infrared detector;
FIG. 8 is a schematic diagram of an infrared detection system according to some embodiments of the present application;
FIG. 9 is a schematic illustration of the difference between the detected gas and the background radiation level in an infrared detection system according to some embodiments of the present application;
FIG. 10 is a schematic diagram of an infrared detection system according to further embodiments of the present application.
Reference numerals: 10. an infrared detector; 11. a pixel; 12. a bridge arm; 13. a bridge deck; 14. an aluminum layer; 141. a reflective layer; 142. a first circuit electrode; 143. a second circuit electrode; 1421. a third via hole; 1422. a fourth via hole; 15. a silicon substrate; 130. an absorbing film system; 131. a small hole; 1301. a cavity layer; 1302. a first dielectric layer; 1303. a metal layer; 1304. a second dielectric layer; 1305. a heat-sensitive layer; 1306. a third dielectric layer; 1307. a conductive layer; 1308. a fourth dielectric layer; 1309. a sacrificial layer; 1311. a first via hole; 1312. a second via hole; 1315. a fifth via hole; 1316. a sixth via; 1317. a first conductive electrode; 1318. a second conductive electrode; 1320. a microbridge structure; 1330. a suspended microbridge structure; 20. a narrow band filter; 30. an optical window; 40. an optical lens; 50. a medium wave light source; 60. a region of gas to be detected; 70. a background environment; 100. an infrared detection system; 320. an imaging system.
Detailed Description
The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the description herein are intended to be within the scope of the present disclosure.
It should be noted that the numerical ranges indicated in the present application, for example, 1000nm to 2000nm, 3 μm to 7 μm, etc., are to be understood as including any value in the numerical ranges consisting of the minimum endpoint value, the maximum endpoint value, and both endpoint values, i.e., the closed interval [1000,2000], the closed intervals [3,7], etc.
As shown in fig. 1 and 2, a first aspect of the present application provides an infrared detector including a pixel array; each pixel 11 in the pixel array comprises a bridge arm 12 and a bridge deck 13, wherein the bridge deck 13 is supported on an aluminum layer 14 through the bridge arm 12, and the aluminum layer 14 is positioned on a silicon substrate 15 provided with a reading circuit; the bridge deck 13 comprises an absorbing film series 130, and the absorbing film series 130 sequentially comprises a cavity layer 1301, a first medium layer 1302, a metal layer 1303, a second medium layer 1304, a heat-sensitive layer 1305 and a third medium layer 1306 in the direction away from the aluminum layer 14.
The first medium layer 1302, the second medium layer 1304 and the third medium layer 1306 are used as absorption layers to absorb a detected object and enable the detected object to enter the absorption film system 130, the metal layer 1303 is used for regulating and controlling the absorption of the detected object, so that the absorption intensity of the absorption film system 130 on the detected object is increased, the temperature of the first medium layer 1302, the second medium layer 1304 and the third medium layer 1306 changes after the infrared energy is absorbed, the resistance value of the thermosensitive layer 1305 changes correspondingly, the change of the resistance value of the thermosensitive layer 1305 is transmitted to the reading circuit, and the reading circuit converts the resistance value into an electric signal to be output. Meanwhile, the first dielectric layer 1302, the second dielectric layer 1304, and the third dielectric layer 1306 also serve as support layers to isolate the metal layer 1303 from the thermal sensitive layer 1305, so as to avoid short circuits.
Due to the total reflection characteristic of the aluminum layer 14, the infrared radiation entering the pixel 11 can be reflected for multiple times in an optical resonant cavity formed by the aluminum layer 14 and the absorption film system 130, and the absorption film system 130 of the present application can gradually absorb the infrared wave within the range of 3 μm to 7 μm in each reflection process through the matching of the layers, so that the main absorption peak of the pixel 11 is moved to a mid-wave region. In this application, "mid-wave" means that the wavelength range lies between 3 μm and 7 μm, spanning the upper limit of the common mid-wave by 5 μm and extending to 7 μm.
On the whole, on the premise of being compatible with the existing long-wave detector manufacturing process, the infrared detector designs the pixel which can be strongly absorbed in the mid-span waveband with the wavelength of 3-7 mu m by adjusting the absorption film system, realizes higher light-heat-electricity conversion rate in the waveband, and effectively improves the infrared radiation absorption rate in the waveband range, for example, as shown in a schematic diagram of the infrared detector pixel absorption rate of the application along with the change of the wavelength shown in fig. 3, it can be seen that the absorption rate of the pixel on the infrared wavelength of 3 mu m-7 mu m can reach more than 95% at most, and the average absorption rate is more than 80%. It will be appreciated that the pixel array has a high absorption at infrared wavelengths from 3 μm to 7 μm. And the absorption film system has simple and easily obtained structure and can be compatible with the existing preparation process of the long-wave detector. In general, the infrared detector has the advantages of high absorptivity, strong signal and simple process in the detection range of the wavelength of 3-7 μm.
Illustratively, referring to fig. 4 and 5, it can be seen that the absorption peaks of the harmful gases methane and nitrogen dioxide are in the range of 3 μm to 7 μm, and therefore, the infrared detector of the present application can be used for the detection of the harmful gases methane and nitrogen dioxide, and those skilled in the art will understand that the infrared detector of the present application can also be used for the detection of the detected objects other than methane and nitrogen dioxide, which are located in the wavelength range of 3 μm to 7 μm.
The number and arrangement of pixels in the pixel array are not particularly limited in the present application as long as the object of the present application can be achieved. For example, the pixels are arranged in N × M to form an array of pixels.
In the present application, the type of the bridge arm is not particularly limited, and those skilled in the art can select the bridge arm according to the structural arrangement of the pixels as long as the purpose of the present application can be achieved. For example, the I-arm, U-arm, or L-arm is preferably an I-arm.
In some embodiments of the present application, as shown in fig. 6, the deck 13 further includes a plurality of small holes 131, and the size of the small holes 131 is not particularly limited as long as the object of the present application can be achieved. For example, the diameter of the pores 131 is 0.5-5 μm, it being understood that the diameter of the pores 131 may be 0.5 μm, 1.0 μm, 2.0 μm, 3.0 μm, 4.0 μm, 5.0 μm, and any value between any two of the above numerical ranges. The number of the small holes 131 and the specific positions thereof on the bridge deck 13 are not particularly limited in the present application as long as the purpose of the present application can be achieved, and fig. 6 is only an illustration and does not show the limitation on the number and positions of the small holes 131. The small holes 131 penetrating through the bridge deck 13 are formed in the bridge deck 13, so that the heat capacity of the picture elements 11 is reduced, the response speed of the picture elements 11 is improved, meanwhile, the release of structural internal stress is facilitated, and the warping of the bridge deck 13 is avoided.
In some embodiments of the present application, the thickness of each layer in the absorbent film system is: cavity layer: 1000nm-2000nm, first dielectric layer: 50nm-70nm, metal layer: 10nm-20nm, a second dielectric layer: 60nm-90nm, thermosensitive layer: 70nm-100nm, a third dielectric layer: 110nm-150 nm. For example, the thickness of the cavity layer may be 1000nm, 1100nm, 1200nm, 1300nm, 1400nm, 1500nm, 1600nm, 1700nm, 1800nm, 1900nm, 2000nm, or any value between any two of the foregoing values. The thickness of the first dielectric layer can be 50nm, 52nm, 55nm, 57nm, 60nm, 64nm, 66nm, 68nm, 70nm, or any value between any two of the foregoing ranges. The thickness of the metal layer may be 10nm, 11nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm, 20nm, or any value between any two of the foregoing values. The thickness of the second dielectric layer can be 60nm, 66nm, 70nm, 73nm, 77nm, 80nm, 85nm, 88nm, 90nm, or any value between any two of the foregoing ranges. The thickness of the thermosensitive layer may be 70nm, 78nm, 80nm, 85nm, 87nm, 90nm, 95nm, 100nm, and any value between any two of the above numerical ranges. The thickness of the third dielectric layer may be 110nm, 120nm, 130nm, 140nm, 150nm, or any value between any two of the foregoing ranges. By controlling the thickness of each layer in the absorption film system within the range, the absorption rate of the absorption film system to infrared radiation is further improved, and the absorption rate of the infrared detector to infrared radiation within a mid-band range of 3-7 microns is further improved.
In some embodiments of the present application, there is no particular limitation on the materials of the first dielectric layer, the second dielectric layer, and the third dielectric layer as long as the object of the present application can be achieved. For example, the materials of the first dielectric layer, the second dielectric layer and the third dielectric layer are each independently selected from any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide, silicon phosphide and the like. Preferably, the materials of the first dielectric layer, the second dielectric layer and the third dielectric layer are selected from silicon nitride, and the silicon nitride is more resistant to high temperature and is not easy to transfer heat. The materials have good strength, light transmission, high temperature resistance and difficult heat transfer, and the materials can be used as the supporting layer of the absorption film system and are also beneficial to the transmission and absorption of infrared radiation.
In some embodiments of the present application, the material of the metal layer is not particularly limited as long as the object of the present application can be achieved. For example, the material of the metal layer is selected from any one of titanium, titanium nitride, nickel, chromium, and the like. Preferably, the material of the metal layer is selected from titanium. The material is selected, so that the metal layer can better regulate and control the absorption of the detected target, and the absorption strength of the absorption film system to the detected target is increased.
In some embodiments of the present application, the material of the thermosensitive layer is not particularly limited, as long as the material having a temperature coefficient of resistance of about-5% to-1% is selected to achieve the object of the present application. For example, the material of the thermosensitive layer is selected from any one of vanadium oxide, polycrystalline silicon (e.g., α -silicon), and the like. Preferably, the material of the thermosensitive layer is selected from vanadium oxide. By selecting the materials, the resistance performance of the thermosensitive layer can be changed after the infrared radiation entering the absorption film system is subjected to temperature change, the resistance value change of the thermosensitive layer is transmitted to the silicon substrate reading circuit through the conductive electrode, and the reading circuit converts the resistance change into an electric signal, so that the imaging of a detected target is facilitated.
The second aspect of the present application provides a method for manufacturing an infrared detector, which includes the following steps:
(1) forming a patterned aluminum layer on the silicon substrate, the patterned aluminum layer including a reflective layer, a first circuit electrode, and a second circuit electrode;
(2) sequentially forming a sacrificial layer and a first dielectric layer on the structure obtained in the step (1);
(3) forming a graphical metal layer, a second medium layer and a thermosensitive layer on the first medium layer;
(4) forming a first patterned dielectric layer and a sacrificial layer on the structure obtained in the step (3) to form a first via hole and a second via hole which penetrate through the first dielectric layer and the sacrificial layer, wherein the first via hole is communicated with the first circuit electrode, and the second via hole is communicated with the second circuit electrode;
(5) forming a third graphical dielectric layer on the structure obtained in the step (4) to form a third via hole, a fourth via hole, a fifth via hole and a sixth via hole which penetrate through the third dielectric layer, wherein the third via hole corresponds to the first via hole and is communicated with the first circuit electrode, the fourth via hole corresponds to the second via hole and is communicated with the second circuit electrode, and the fifth via hole and the sixth via hole are communicated with the thermosensitive layer;
(6) forming a patterned conductive layer on the structure obtained in the step (5), wherein the patterned conductive layer comprises a first conductive electrode and a second conductive electrode; the first conductive electrode penetrates through the third through hole to be electrically connected with the first circuit electrode, and the first conductive electrode also penetrates through the fifth through hole to be electrically connected with the thermosensitive layer; the second conductive electrode passes through the fourth through hole to be connected with the second circuit electrode, and the second conductive electrode also passes through the sixth through hole to be connected with the thermosensitive layer;
(7) forming a fourth dielectric layer on the structure obtained in the step (6);
(8) etching the structure obtained in the step (7) to form a micro-bridge structure; and etching the sacrificial layer to form a cavity layer on the sacrificial layer, thereby obtaining the suspension micro-bridge structure.
In the step (1), forming a patterned aluminum layer on the silicon substrate may specifically include: and forming an aluminum layer on the silicon substrate, and etching the aluminum layer to pattern the aluminum layer. In the step (4), forming the patterned first dielectric layer and the patterned sacrificial layer may specifically include: and (4) etching the first dielectric layer and the sacrificial layer in sequence on the part which does not contain the patterned metal layer, the second dielectric layer and the thermosensitive layer in the structure obtained in the step (3) to pattern the first dielectric layer and the sacrificial layer. In the step (5), forming a patterned third dielectric layer on the structure obtained in the step (4), which may specifically include: and (4) forming a third dielectric layer on the structure obtained in the step (4), and etching the third dielectric layer to pattern the third dielectric layer. In the step (6), forming a patterned conductive layer on the structure obtained in the step (5), which may specifically include: and (5) forming a conductive layer on the structure obtained in the step (5), and etching the conductive layer to pattern the conductive layer. And (8) etching the structure obtained in the step (7) to form a micro-bridge structure, specifically, integrally etching the structure obtained in the step (7) according to the patterning process requirement, and not only etching the fourth dielectric layer. In a specific area required by a specific patterning process, etching needs to be started from the fourth dielectric layer, and the existing layers are sequentially etched (due to the difference of patterning of the layers in the steps (1) to (6), the number of layers in different areas may be different in the structure obtained in the step (7)) until the whole first dielectric layer is etched away, so that the microbridge structure is formed. The microbridge structure comprises a sacrificial layer, a first graphical dielectric layer, a metal layer, a second dielectric layer, a thermosensitive layer, a third dielectric layer, a conductive layer and a fourth dielectric layer. The suspension micro-bridge structure is an integral structure obtained by etching a sacrificial layer in the micro-bridge structure and forming a cavity layer after the sacrificial layer is released.
In some embodiments of the present application, when the patterns of the metal layer, the second dielectric layer and the heat sensitive layer are uniform, the step (3) includes: and then etching the heat-sensitive layer, the second medium layer and the metal layer in sequence to pattern the heat-sensitive layer, the second medium layer and the metal layer. Therefore, the preparation process is simpler and the preparation cost is lower.
In some embodiments of the present application, when the patterns of the metal layer, the second dielectric layer and the thermosensitive layer are not uniform, the step (3) includes:
(a) forming a metal layer on the first dielectric layer, and etching the metal layer to pattern the metal layer;
(b) forming a second dielectric layer on the structure obtained in the step (a), and etching the second dielectric layer to pattern the second dielectric layer;
(c) forming a heat-sensitive layer on the structure obtained in the step (b), and etching the heat-sensitive layer to pattern the heat-sensitive layer.
In some embodiments of the present application, when two adjacent layers of the patterns of the metal layer, the second dielectric layer, and the heat sensitive layer are uniform and the other layer is not uniform with the other two layers, the two adjacent and uniform layers may be sequentially formed and then sequentially etched. The other layer which is not uniform with the other two layers is separately formed and separately etched. Therefore, the preparation process can be simplified, and the production cost can be saved. Illustratively, in some embodiments of the present application, when the metal layer and the second dielectric layer are patterned uniformly, the metal layer is formed on the first dielectric layer, the second dielectric layer is formed on the metal layer, and the second dielectric layer and the metal layer are etched in sequence to pattern the second dielectric layer and the metal layer; and then forming a heat-sensitive layer on the structure, and etching the heat-sensitive layer to pattern the heat-sensitive layer. In other embodiments of the present application, when the second dielectric layer and the thermal sensitive layer are patterned uniformly, a metal layer is formed on the first dielectric layer, and the metal layer is etched to pattern the metal layer; and then forming a second medium layer on the structure, forming a heat-sensitive layer on the second medium layer, and etching the heat-sensitive layer and the second medium layer in sequence to pattern the heat-sensitive layer and the second medium layer.
The pattern of each layer in any of the embodiments described above in the present application is not particularly limited, and may be selected by those skilled in the art according to the actual situation as long as the object of the present application can be achieved. It should be understood that, according to different patterns, the arrangement positions of the reflective layer, the first circuit electrode, the first via hole, the second via hole, the third via hole, the fourth via hole, the fifth via hole, the sixth via hole, the first conductive electrode, and the second conductive electrode in each step of the method for manufacturing an infrared detector may be changed, and those skilled in the art may adjust the positions according to the patterns, which is not limited in the present application. It should be noted that an optical resonant cavity is formed between the reflective layer and the absorption film system to generate multiple reflections of the detected object, and each layer in the absorption film system and the reflective layer are disposed opposite to each other in the direction of absorbing the detected object, and specifically, those skilled in the art can adjust the optical resonant cavity according to the pattern.
The sizes of the first via hole, the second via hole, the third via hole, the fourth via hole, the fifth via hole and the sixth via hole are not particularly limited, and those skilled in the art can select the sizes according to the actual conditions as long as the purposes of the present application can be achieved. In this application, the diameter of third via hole is less than first via hole, and the diameter of fourth via hole is less than the second via hole, like this, can prevent that first circuit electrode and second circuit electrode from exposing in the air, reduces the risk that first circuit electrode and second circuit electrode are corroded, and then improves infrared detector's accuracy and life.
The preparation method of the infrared detector is simple in process, easy to operate, easy in raw material obtaining and capable of being widely applied to industrial production.
In some embodiments of the present application, the thickness of the cavity layer is 1000nm to 2000nm, the thickness of the first dielectric layer is 50nm to 70nm, the thickness of the metal layer is 10nm to 20nm, the thickness of the second dielectric layer is 60nm to 90nm, the thickness of the thermosensitive layer is 70nm to 100nm, and the thickness of the third dielectric layer is 110nm to 150 nm.
The thickness of the sacrificial layer in the present application may be the same as the thickness of the cavity layer, which is 1000nm to 2000 nm. The thicknesses of the aluminum layer, the conductive layer and the fourth dielectric layer are not particularly limited in the present application, and may be selected by those skilled in the art according to the actual application, as long as the object of the present application can be achieved.
In some embodiments of the present application, after the step (7), the fourth dielectric layer, the conductive layer, the third dielectric layer, the thermosensitive layer, the second dielectric layer, the metal layer, the first dielectric layer and the sacrificial layer may be sequentially etched to form a plurality of small holes, and the diameter of the small holes is 0.5 μm to 5 μm.
In some embodiments of the present application, the aluminum layer, the metal layer, and the conductive layer are each independently formed by a physical vapor deposition method; the sacrificial layer is formed by a gluing method; the first dielectric layer, the second dielectric layer, the third dielectric layer and the fourth dielectric layer are formed independently by a chemical vapor deposition method, and the thermosensitive layer is formed by a reactive sputtering method.
In some embodiments of the present application, the method of etching the aluminum layer, the metal layer, the second dielectric layer, the thermosensitive layer, the sacrificial layer, the first dielectric layer, the third dielectric layer, the conductive layer, and the fourth dielectric layer includes a dry etching process.
In some embodiments of the present application, there is no particular limitation on the material of the sacrificial layer as long as the object of the present application can be achieved. For example, the material of the sacrificial layer is selected from polyimide. Polyimide is selected to form a sacrificial layer, so that the micro-bridge structure is not easily damaged when the cavity layer is formed by etching. Moreover, polyimide has good insulation, large elastic coefficient and linear expansion coefficient, can bear large strain and has good mechanical performance in a wide temperature range.
In some embodiments of the present application, there is no particular limitation on the materials of the first dielectric layer, the second dielectric layer, the third dielectric layer, and the fourth dielectric layer as long as the object of the present application can be achieved. For example, the materials of the first dielectric layer, the second dielectric layer, the third dielectric layer and the fourth dielectric layer are each independently selected from any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide and silicon phosphide. Preferably, the materials of the first dielectric layer, the second dielectric layer, the third dielectric layer and the fourth dielectric layer are all selected from silicon nitride, and the silicon nitride is more resistant to high temperature and is not easy to transfer heat. The materials have good strength, light transmission, high temperature resistance and difficult heat transfer, and the materials can be used as the supporting layer of the absorption film system and are also beneficial to the transmission and absorption of infrared radiation.
In some embodiments of the present application, there is no particular limitation on the materials of the metal layer and the conductive layer as long as the object of the present application can be achieved. For example, the material of the metal layer and the conductive layer is selected from any one of titanium, titanium nitride, nickel, and chromium. The materials are selected, so that the metal layer can better regulate and control the absorption of the detected target, the absorption strength of the absorption film system to the detected target is increased, and the conductive layer has good conductivity.
In some embodiments of the present application, the material of the thermosensitive layer is not particularly limited as long as the object of the present application can be achieved. For example, the material of the thermosensitive layer is selected from any one of vanadium oxide, polycrystalline silicon (e.g., α -silicon), and the like. Preferably, the material of the thermosensitive layer is selected from vanadium oxide. By selecting the materials, the resistance performance of the thermosensitive layer can be changed after the infrared radiation entering the absorption film system is subjected to temperature change, the resistance value change of the thermosensitive layer is transmitted to the silicon substrate reading circuit through the conductive electrode, and the reading circuit converts the resistance change into an electric signal, so that the imaging of a detected target is facilitated.
For example, in some embodiments of the present application, as shown in fig. 7 a-7 l, a method of making an infrared detector includes the steps of:
(1) forming an aluminum layer 14 on a silicon substrate 15 by a physical vapor deposition method, as shown in fig. 7 a;
(2) patterning the aluminum layer 14 by etching the aluminum layer 14 through a dry etching process, the patterned aluminum layer 14 including a reflective layer 141, a first circuit electrode 142 and a second circuit electrode 143, as shown in fig. 7 b;
(3) coating polyimide on the structure obtained in the step (2) to form a sacrificial layer 1309, as shown in fig. 7 c;
(4) growing any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide and silicon phosphide on the sacrificial layer 1309 by a chemical vapor deposition method to form a first dielectric layer 1302, as shown in fig. 7 d;
(5) growing any one of titanium, titanium oxide, nickel and chromium on the first dielectric layer 1302 by a physical vapor deposition method to form a metal layer 1303; growing any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide and silicon phosphide on the metal layer 1303 by using a chemical vapor deposition method to form a second dielectric layer 1304; growing a layer of vanadium oxide or amorphous silicon on the second dielectric layer 1304 by a reactive sputtering method to form a thermosensitive layer 1305; then, sequentially etching the thermal sensitive layer 1305, the second dielectric layer 1304 and the metal layer 1303 by a dry etching process, so that the thermal sensitive layer 1305, the second dielectric layer 1304 and the metal layer 1303 are patterned, as shown in fig. 7 e;
(6) in the structure obtained in step (5), on the portion not containing the patterned metal layer 1303, the second dielectric layer 1304 and the thermosensitive layer 1305, sequentially etching the first dielectric layer 1302 and the sacrificial layer 1309 by a dry etching process to form the patterned first dielectric layer 1302 and the sacrificial layer 1309 so as to form a first via 1311 and a second via 1312 passing through the first dielectric layer 1302 and the sacrificial layer 1309, where the first via 1311 is communicated with the first circuit electrode 142, and the second via 1312 is communicated with the second circuit electrode 143, as shown in fig. 7 f;
(7) growing any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide and silicon phosphide on the structure obtained in the step (6) by a chemical vapor deposition method to form a third dielectric layer 1306, wherein as shown in fig. 7g, the third dielectric layer 1306 can be used as a support layer of a bridge arm;
(8) etching the third dielectric layer 1306 by a dry etching process to form a patterned third dielectric layer 1306, so as to form a third via 1421, a fourth via 1422, a fifth via 1315 and a sixth via 1316 passing through the third dielectric layer, wherein the third via 1421 corresponds to the first via 1311 (see fig. 7f) and is communicated with the first circuit electrode 142, the fourth via 1422 corresponds to the second via 1312 (see fig. 7f) and is communicated with the second circuit electrode 143, and the fifth via 1315 and the sixth via 1316 is communicated with the heat-sensitive layer 1305, as shown in fig. 7 h;
(9) growing any one of titanium, titanium oxide, nickel and chromium on the structure obtained in the step (8) by a physical vapor deposition method to form a conductive layer 1307, and then etching the conductive layer 1307 by a dry etching process to form a patterned conductive layer 1307, wherein the patterned conductive layer 1307 comprises a first conductive electrode 1317 and a second conductive electrode 1318; the first conductive electrode 1317 is electrically connected to the first circuit electrode 142 through a third via 1421 (see fig. 7h), and the first conductive electrode 1317 is also electrically connected to the thermosensitive layer 1305 through a fifth via 1315 (see fig. 7 h); the second conductive electrode 1318 is electrically connected to the second circuit electrode 143 through a fourth via 1422 (see fig. 7h), and the second conductive electrode 1318 is also electrically connected to the thermosensitive layer 1305 through a sixth via 1316 (see fig. 7h), as shown in fig. 7 i. Thus, the thermosensitive layer 1305 forms a closed loop with the first circuit electrode 143 and the second circuit electrode 143, the resistance value of the thermosensitive layer 1305 is transmitted to the readout circuit of the silicon substrate 15 via the first conductive electrode 1317/the second conductive electrode 1318, the first circuit electrode 142/the second circuit electrode 143, and the readout circuit converts the change of the resistance value of the thermosensitive layer 1305 into an electric signal;
(10) growing any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide and silicon phosphide on the structure obtained in the step (9) by a chemical vapor deposition method to form a fourth dielectric layer 1308 as shown in fig. 7 j;
(11) etching the structure obtained in the step (10) by a dry etching process to form a microbridge structure 1320, as shown in fig. 7 k; and etching the sacrificial layer 1309 by a dry etching process to form a cavity layer 1301 on the sacrificial layer 1309 to obtain a suspension micro-bridge structure 1330, as shown in fig. 7l, that is, the infrared detector is obtained.
A third aspect of the present application provides an infrared detection system comprising an infrared detector as provided in the first aspect of the present application. Therefore, the infrared detection system has high absorptivity for the detected target with the infrared wavelength of 3-7 μm.
Fig. 8 is a schematic diagram of the infrared detection system according to some embodiments of the present application, and referring to fig. 8, the infrared detection system 100 includes an optical lens 40, an optical window 30, an infrared detector 10, and an imaging system 320. Specifically, infrared radiation emitted by the detected target area 60 and the background environment 70 passes through the optical lens 40 after being focused and passes out in parallel, enters the infrared detector 10 through the optical window 30, and is converted into an electrical signal by each pixel 11 in the infrared detector 10, and then is imaged on the imaging system 320.
In some embodiments of the present application, the infrared detection system further comprises a medium wave light source, the medium wave light source emitting light with a wavelength of 3 μm to 5 μm. Through set up the medium wave light source in infrared detection system, to being surveyed the target (for example harmful gas such as methane, nitrogen dioxide) initiative illumination, originally by the detection region owing to received the beam radiation of light source, in the absorption wavelength range of being surveyed gaseous, can further amplify the difference of gas and background environment radiant quantity to output signal intensity among the reinforcing infrared detector, and then effectively improve infrared detection system's detection sensitivity and ultimate formation of image contrast also improved, provide sensitive, effectual visual detection for being surveyed the target. The above-mentioned "active illumination" means that the amount of infrared radiation of the detected object is changed by applying light source irradiation to the detected object on the basis of the infrared radiation generated by the detected object itself. Fig. 9 is a schematic diagram illustrating a difference between detected gas and background radiation in an infrared detection system according to some embodiments of the present application, where a line a is a difference between detected gas and background radiation when no active illumination is applied, and a line b is a difference between detected gas and background radiation when active illumination is applied, and it can be seen that the difference between detected gas and background radiation after active illumination is applied is significantly increased under the same detected gas concentration.
In the present application, there is no particular limitation on the kind of the medium-wave light source device as long as the object of the present application can be achieved. For example, the medium wave light source device may include a semiconductor laser or the like.
In some embodiments of the present application, the infrared detection system further comprises a narrow-band filter, the narrow-band filter being disposed between the optical window and the infrared detector, the narrow-band filter having a transmittance of 80% or more in the infrared band of 3 μm to 7 μm and a transmittance of 10% or less in the remaining range, i.e., a transmittance of 10% or less in the infrared band other than 3 μm to 7 μm. It should be noted that, according to actual needs, a person skilled in the art can select a narrow-band filter capable of defining a specific band of 3 μm to 7 μm, for example, a narrow-band filter defining a specific band of 3.25 μm to 3.4 μm or 6.1 μm to 6.2 μm. Through the selection of the narrow-band filter, the radiation wave band entering the infrared detector can be limited, and therefore the imaging sensitivity of the detected target in the corresponding wave band is effectively improved.
Fig. 10 is a schematic diagram of the infrared detection system according to other embodiments of the present application, and referring to fig. 2, 4-5 and 10, when harmful gases such as methane and nitrogen dioxide are detected, infrared radiation emitted by gas molecules in a corresponding wavelength absorption range is reduced due to infrared spectrum absorption characteristics of the detected gases such as methane and nitrogen dioxide, which forms a radiation energy difference with a background environment 70 in which infrared absorption does not occur. The medium wave light source 50 irradiates on the detected gas area 60, the infrared radiation emitted by the detected gas area 60 and the background environment 70 is focused by the optical lens 40 and then parallelly penetrates out, and enters the narrow band filter 20 through the optical window 30, because the transmittance of the narrow band filter 20 to the infrared band range of 3-7 μm is high, the infrared radiation in the band range irradiates on the infrared detector 10 after penetrating through the narrow band filter 20, and the transmittance of other infrared radiation outside the band range is low, and is basically blocked outside the narrow band filter 20. The infrared radiation irradiated on the infrared detector 10 is absorbed by the absorption film system 130 on each pixel 11 in the infrared detector 10 and converted into a temperature change, and the changed temperature changes the resistance property of the thermosensitive layer 1305, and the resistance change is converted into a voltage signal and imaged on the imaging system 320 by being connected with a readout circuit of the silicon substrate 15 through the metal layer 1303. Because the radiation amount of the detected gas and the background environment 70 in the narrow band is different, the absorption amount of the pixel 11 on the corresponding position to the infrared radiation is different, and the voltage change is also different, an image with different brightness degrees can be correspondingly formed on the imaging system 320. When the medium wave light source 50 is added for active illumination, the radiation energy difference between the background environment 70 and the gas under a certain concentration is further amplified, and the detection effect is effectively improved.
It is noted that, herein, relational terms such as "first," "second," "third," "fourth," and the like may be used solely to distinguish one entity from another entity without necessarily requiring or implying any actual such relationship or order between such entities.
In this document, the terms "upper", "top", "bottom", "far away", and the like refer to orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing corresponding technical solutions of the present application and simplifying the description, but do not indicate or imply that a device or an element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present application.
The above description is only for the preferred embodiment of the present application and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application are included in the protection scope of the present application.
Claims (21)
1. An infrared detector includes an array of pixels;
each pixel in the pixel array comprises a bridge arm and a bridge floor, and the bridge floor is supported on the aluminum layer through the bridge arm;
the bridge deck comprises an absorption film system, and the absorption film system sequentially comprises a cavity layer, a first medium layer, a metal layer, a second medium layer, a thermosensitive layer and a third medium layer in the direction away from the aluminum layer.
2. The infrared detector as set forth in claim 1, wherein the thicknesses of the layers in the absorbing film system are:
cavity layer: 1000nm-2000nm, first dielectric layer: 50nm-70nm, metal layer: 10nm-20nm, a second dielectric layer: 60nm-90nm, thermosensitive layer: 70nm-100nm, a third dielectric layer: 110nm-150 nm.
3. The infrared detector of claim 1, wherein the bridge deck further comprises a plurality of pores, the pores having a diameter of 0.5-5 μ ι η.
4. The infrared detector as set forth in claim 1, wherein the materials of the first, second, and third dielectric layers are each independently selected from any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide, and silicon phosphide.
5. The infrared detector according to claim 1, wherein a material of the metal layer is selected from any one of titanium, titanium nitride, nickel, and chromium.
6. The infrared detector as set forth in claim 1, wherein a material of the thermosensitive layer is selected from any one of vanadium oxide and amorphous silicon.
7. The infrared detector of claim 1, wherein the picture elements have an average absorption greater than 80% in the infrared band of wavelengths from 3 μ ι η to 7 μ ι η.
8. The infrared detector as set forth in claim 1, wherein a detection wavelength of the infrared detector is 3 μm-7 μm.
9. A preparation method of an infrared detector comprises the following steps:
(1) forming a patterned aluminum layer on a silicon substrate, the patterned aluminum layer including a reflective layer, a first circuit electrode, and a second circuit electrode;
(2) sequentially forming a sacrificial layer and a first dielectric layer on the structure obtained in the step (1);
(3) forming a graphical metal layer, a second dielectric layer and a thermosensitive layer on the first dielectric layer;
(4) forming a first patterned dielectric layer and a sacrificial layer on the structure obtained in the step (3) to form a first via hole and a second via hole which penetrate through the first dielectric layer and the sacrificial layer, wherein the first via hole is communicated with the first circuit electrode, and the second via hole is communicated with the second circuit electrode;
(5) forming a third patterned dielectric layer on the structure obtained in the step (4) to form a third via hole, a fourth via hole, a fifth via hole and a sixth via hole, wherein the third via hole penetrates through the third dielectric layer, the third via hole corresponds to the first via hole and is communicated with the first circuit electrode, the fourth via hole corresponds to the second via hole and is communicated with the second circuit electrode, and the fifth via hole and the sixth via hole are communicated with the thermosensitive layer;
(6) forming a patterned conductive layer on the structure obtained in the step (5), wherein the patterned conductive layer comprises a first conductive electrode and a second conductive electrode; the first conductive electrode penetrates through the third through hole to be electrically connected with the first circuit electrode, and the first conductive electrode also penetrates through the fifth through hole to be electrically connected with the thermosensitive layer; the second conductive electrode penetrates through the fourth through hole to be electrically connected with the second circuit electrode, and the second conductive electrode also penetrates through the sixth through hole to be electrically connected with the thermosensitive layer;
(7) forming a fourth dielectric layer on the structure obtained in the step (6);
(8) etching the structure obtained in the step (7) to form a micro-bridge structure; and etching the sacrificial layer to form a cavity layer on the sacrificial layer, thereby obtaining the suspension micro-bridge structure.
10. The production method according to claim 9, wherein step (3) includes:
forming a metal layer on the first dielectric layer, forming a second dielectric layer on the metal layer, forming a heat-sensitive layer on the second dielectric layer, and then sequentially etching the heat-sensitive layer, the second dielectric layer and the metal layer to pattern the heat-sensitive layer, the second dielectric layer and the metal layer.
11. The production method according to claim 9, wherein step (3) includes:
(a) forming a metal layer on the first dielectric layer, and etching the metal layer to pattern the metal layer;
(b) forming a second dielectric layer on the structure obtained in the step (a), and etching the second dielectric layer to pattern the second dielectric layer;
(c) forming a thermosensitive layer on the structure obtained in the step (b), and etching the thermosensitive layer to pattern the thermosensitive layer.
12. The manufacturing method according to claim 9, wherein the thickness of the cavity layer is 1000nm to 2000nm, the thickness of the first dielectric layer is 50nm to 70nm, the thickness of the metal layer is 10nm to 20nm, the thickness of the second dielectric layer is 60nm to 90nm, the thickness of the heat-sensitive layer is 70nm to 100nm, and the thickness of the third dielectric layer is 110nm to 150 nm.
13. The manufacturing method according to claim 9, wherein after the step (7), the fourth dielectric layer, the conductive layer, the third dielectric layer, the heat sensitive layer, the second dielectric layer, the metal layer, the first dielectric layer and the sacrificial layer are sequentially etched to form a plurality of small holes, and the diameter of each small hole is 0.5 μm to 5 μm.
14. The method of claim 13, wherein the etching the aluminum layer, the sacrificial layer, the first dielectric layer, the metal layer, the second dielectric layer, the thermal sensitive layer, the third dielectric layer, the conductive layer, and the fourth dielectric layer comprises a dry etching process.
15. The production method according to claim 9, wherein a material of the sacrificial layer is selected from polyimide.
16. The manufacturing method according to claim 9, wherein the materials of the first dielectric layer, the second dielectric layer, the third dielectric layer and the fourth dielectric layer are each independently selected from any one of silicon nitride, silicon oxide, silicon carbide, silicon sulfide and silicon phosphide.
17. The production method according to claim 9, wherein the materials of the metal layer and the conductive layer are each independently selected from any one of titanium, titanium nitride, nickel, and chromium.
18. The manufacturing method according to claim 9, wherein a material of the thermosensitive layer is selected from any one of vanadium oxide and amorphous silicon.
19. An infrared detection system comprising the infrared detector of any one of claims 1-8.
20. The infrared detection system of claim 19, further comprising a medium wave light source having a light emission wavelength of 3 μ ι η -5 μ ι η.
21. The infrared detection system of claim 19 or 20, further comprising a narrow band filter disposed between the optical window and the infrared detector, the narrow band filter having a transmittance of 80% or more in the infrared band of 3 μm to 7 μm and a transmittance of 10% or less in the remaining range.
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| CN202111071002.6A CN113659015A (en) | 2021-09-13 | 2021-09-13 | Infrared detector, preparation method thereof and infrared detection system |
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| CN116885040A (en) * | 2023-07-24 | 2023-10-13 | 镭友芯科技(苏州)有限公司 | Photodetector device and preparation method thereof |
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