CN102928089A - Uncooled pyroelectric linear focal plane and manufacturing method thereof - Google Patents
Uncooled pyroelectric linear focal plane and manufacturing method thereof Download PDFInfo
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- CN102928089A CN102928089A CN201210431102XA CN201210431102A CN102928089A CN 102928089 A CN102928089 A CN 102928089A CN 201210431102X A CN201210431102X A CN 201210431102XA CN 201210431102 A CN201210431102 A CN 201210431102A CN 102928089 A CN102928089 A CN 102928089A
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Abstract
The invention discloses an uncooled pyroelectric linear focal plane and a manufacturing method thereof. According to the invention, the extending electrode area of a photosensitive chip and a substrate matched with the photosensitive chip in size are together bonded by designing the sizes and structures of photosensitive elements and electrodes so that photosensitive element areas are in suspension states; a heat-insulating groove is formed by etching between adjacent photosensitive elements, so that the heat conductance between the photosensitive elements can be reduced, and crosstalk can be reduced; a reading circuit is designed according to the characteristic parameters of the pyroelectric photosensitive chip, and the input stages of the reading amplification circuit adopting a current integration mode correspond to the pyroelectric photosensitive chip one by one. The uncooled pyroelectric linear focal plane disclosed by the invention adopts a hybrid-type structure, and the pyroelectric photosensitive chip and the reading circuit are mutually connected and coupled through a lead bonding process and encapsulated by adopting a metal pipe shell. The manufacturing process of the uncooled pyroelectric linear focal plane disclosed by the invention comprises process technologies, namely photosensitive chip thinning, damage and flaw removal, electrode forming, absorbing layer preparation, lead bonding, and the like.
Description
Technical field
The present invention relates to a kind of focal plane device and manufacturing process thereof.Be specifically related to a kind of non-refrigeration pyroelectricity Linear FPA and method of manufacturing technology thereof.
Background technology
The Uncooled infrared detection technology does not need refrigeration system at work, has widely application.Pyroelectric effect is that spontaneous polarization meeting that pyroelectricity material has varies with temperature and the phenomenon that changes, can be used for the detection to infrared radiation.The pyroelectricity Linear FPA belongs to the thermistor detector field of non-refrigeration based on pyroelectric effect work.Compare with photon detector, it have can at room temperature work and do not need refrigerating system, compact conformation, weight is light, reliability is high, spectral response is wide and smooth, the plurality of advantages such as cheap, the shortcoming that the pyroelectricity Linear FPA is low with respect to photon detector responsiveness and detectivity, response speed is slow can remedy by making highdensity array.Compare with the thermal resistance non-refrigeration focal surface with thermoelectric pile, the pyroelectricity Linear FPA has fast response time, high, the simple advantage of technique of signal to noise ratio (S/N ratio).Non-refrigeration pyroelectricity focal plane is the core devices of thermal infrared imager and spectrometer, is widely used in the numerous areas such as industry, medical science and scientific research.Relaxor ferroelectric monocrystal Mn-(1-x) Pb (Mg
1/3Nb
2/3) O
3-xPbTiO
3(Mn-PMNT) be a kind of novel pyroelectricity material, 1. have larger pyroelectric coefficient (p 〉=8.0 * 10 at room temperature
-4C/m
2K); 2. have the higher electric current figure of merit and survey the figure of merit, the electric current figure of merit and the detection figure of merit have low temperature and frequencydependence characteristic, so that Mn-PMNT pyroelectricity focal plane possesses wide frequency of operation and temperature range; 3. relative dielectric constant can be regulated in the 300-8000 scope, is conducive to the matched well of focal plane and amplifying circuit; 4. has higher Curie temperature (T
c～120 ℃), physicochemical property are stable; 5. have large coercive field, be difficult for depolarization; 6. lower (D～4.4 * 10 of thermal diffusion coefficient
-7m
2/ s), being conducive to obtain 7. thickness hour (thickness≤60 μ m), the Mn-PMNT crystal is transparence at visible-range, is beneficial to photoetching process and aims at exposure.Mn-PMNT has the pyroelectric property of comprehensive excellence, aspect the non-refrigeration Linear FPA very large application potential is being arranged.Therefore, research and development have important Practical significance based on the non-refrigeration Linear FPA technique of Mn-PMNT.
Summary of the invention
Based on novel pyroelectricity material relaxor ferroelectric monocrystal Mn-PMNT, the invention provides the process of a kind of alignment structural design and manufacturing Linear FPA.Researched and developed the manufacturing process based on the Linear FPA of novel pyroelectricity material Mn-PMNT.The outer focal plane of line self-supporting hanging structure can improve the heat-proof quality of focal plane and environment, and is beneficial to the electric coupling encapsulation of device, has improved yield rate.
Non-refrigeration pyroelectricity Linear FPA provided by the present invention is by the photosensitive area hanging structure of pyroelectricity alignment substrate, self-supporting, heat dam structure, sensing circuit, photosensor chip and sensing circuit bonding wire structure between the adjacent photosensitive unit.
A kind of non-refrigeration pyroelectricity Linear FPA, it is characterized in that the structure of focal plane is followed successively by the pyroelectricity alignment substrate 10 of white stone material from bottom to top, adhesive glue 8, pyroelectricity photosensor chip support substrates 9 at pyroelectricity alignment substrate left 1/3rd places, be bonded together by adhesive glue 8 and the pyroelectricity photosensor chip 1 above it, / 2nd of a unsettled chip width in pyroelectricity photosensor chip 1 left side, at the unsettled place of pyroelectricity photosensor chip lower surface deposit public electrode 7, upper surface deposit chromium nickel absorption layer is as photosensitive unit 2, and deposit chromium gold metallic film is as extension electrode 3; / 3rd places are readout circuit chips 6 on pyroelectricity alignment substrate right side, and the sensing circuit input terminal electrode 5 on it connects coupling by bonding wire 4 with the extension electrode 3 of pyroelectricity photosensor chip.
Described pyroelectricity photosensor chip 1 adopts Mn-(1-x) Pb (Mg
1/3Nb
2/3) O
3-xPbTiO
3(Mn-PMNT) relaxor ferroelectric monocrystal;
Described photosensitive unit 2 is the chrome-nickel alloy film;
Described extension electrode 3 is chromium gold metallic film;
Described bonding wire 4 is Si-Al wire;
Described sensing circuit input terminal electrode 6 is aluminum metal films;
Described public electrode 7 is chromium gold metallic film;
Described adhesive glue 8 is epoxy glue;
Described pyroelectricity photosensor chip support substrates 9 adopts white stone;
Described pyroelectricity alignment substrate 10 is white stone;
Non-refrigeration Linear FPA provided by the invention, realize by following technological process:
1) two of the Mn-PMNT wafer surfaces are labeled as respectively A face and B face.
2) the Mn-PMNT wafer of cleaning＜111〉direction polarization.
3) the A face with the Mn-PMNT wafer sticks on the substrate with wax, and Mn-PMNT wafer B face is carried out mechanical reduction and polishing.
4) the Mn-PMNT wafer is added hot melt wax from substrate and take off, clean the Mn-PMNT wafer.At room temperature with buffered hydrofluoric acid solution corrosion Mn-PMNT wafer B surface.
5) clean the Mn-PMNT wafer that has corroded, at B face photolithography patterning.
6) at Mn-PMNT wafer B face deposit chromium thin nickel metal film.Floating glue cleans.
7) at Mn-PMNT wafer B face photolithography patterning.
8) at Mn-PMNT wafer B face deposit chromium gold layer, preparation extension electrode.Floating glue cleans.
9) at Mn-PMNT wafer B face photolithography patterning.
10) at Mn-PMNT wafer B face deposit chrome-nickel alloy film absorption layer.Floating glue cleans.
11) at Mn-PMNT wafer B face photolithography patterning, form the heat dam etching mask.
12) adopt the method for argon ion etching to form heat dam between the photosensitive unit at Mn-PMNT wafer B face.
13) the Mn-PMNT wafer is added hot melt wax from substrate and take off, clear first Mn-PMNT wafer is attached to the B face first on the white stone substrate, will be attached on the substrate with the Mn-PMNT wafer of white stone substrate again.The method of employing mechanical lapping is carried out attenuate and polishing to the A face of Mn-PMNT wafer.
14) clean, at Mn-PMNT wafer A face photolithography patterning.
15) prepare chromium gold layer public electrode at Mn-PMNT wafer A face.
16) will take off with the dewaxing from the substrate of the Mn-PMNT wafer of substrate.Scribing is cleaned.
17) adopt epoxy glue bonding pyroelectricity photosensor chip and rpyroelectric infrared photosensor chip substrate, form the photosensitive area hanging structure of self-supporting, at room temperature solidify.
18) with photosensor chip and sensing circuit Bonding, encapsulating package.
The pyroelectricity Linear FPA of structure of the present invention and technique has following advantage: photosensor chip adopts the self-supporting hanging structure, can effectively reduce the thermal conductance between photosensor chip and environment, improves voltage responsive rate and the detectivity of Linear FPA; The manufacturing process simple and stable of focal plane, good reproducibility, cost is low.Adopt chrome-nickel alloy film absorption layer, chromium nickel absorption layer has that heat conductivility is good, specific heat capacity is little, spectral response is wide and smooth, adhesion-tight and the high advantage of absorptivity, and chrome-nickel alloy film absorption layer is as the photosensor chip top electrode simultaneously; Adopt the heat dam structure between photosensitive unit, to reduce crosstalking between the photosensitive unit.
Description of drawings
Fig. 1 is the non-refrigeration Linear FPA of a kind of pyroelectricity of the present invention structure.
Fig. 2 is adjacent photosensitive first interval heat channel structure.
Among the figure, 1. pyroelectricity photosensor chip; 2. photosensitive unit; 3. extension electrode; 4. bonding wire; 5. sensing circuit input terminal electrode; 6. readout circuit chip; 7. public electrode; 8. adhesive glue; 9. pyroelectricity photosensor chip support substrates; 10. pyroelectricity alignment substrate; 11. heat dam.
Embodiment
Below in conjunction with accompanying drawing, by embodiment the present invention is described in further details, but protection scope of the present invention is not limited to the following examples.
128 * 1 pyroelectricity Linear FPAs based on the Mn-PMNT material have adopted structural design provided by the present invention and technological process.The Mn-PMNT material of preparation 128 * 1 pyroelectricity alignment infrared focus planes is＜111〉direction polarizes in advance, the thickness of initial wafer is 500 μ m, finally be made as Linear FPA chip thickness 25 μ m, adopt wet etching to remove defective and the damage of wafer surface.Mn-PMNT pyroelectricity photosensor chip 1 and pyroelectricity photosensor chip support substrates 9 consist of the photosensitive area hanging structure of self-supporting, have reduced the thermal conductance of photosensitive area and environment, support for extension electrode 3 districts provide enough Bonding machinery.Photosensitive unit 2 has smooth broadband absorption, adhesion-tight, specific heat capacity is little, easy and the advantage of the photosensitive focal plane chip process compatible of alignment.As shown in Figure 1.
Realize that process implementing of the present invention is for example lower:
(1) at the upper surface growth chromium nickel absorption layer of Mn-PMNT and the electrode that goes between.
1) the Mn-PMNT wafer is labeled as respectively A face and B face in two surfaces up and down, and in the whole technological process, temperature is controlled at and is lower than 65 ℃.
2) clean thickness be 500 μ m＜111〉direction polarization Mn-PMNT wafer.
3) the A face with the Mn-PMNT wafer sticks on the substrate with wax, and Mn-PMNT wafer B face is carried out mechanical reduction and is polished to 400 μ m.
4) the Mn-PMNT wafer is added hot melt wax from substrate and take off, clean the Mn-PMNT wafer.At room temperature with buffered hydrofluoric acid solution corrosion Mn-PMNT wafer B surface.
5) clean the Mn-PMNT wafer that has corroded, at B face photolithography patterning.
6) at Mn-PMNT wafer B face deposit chromium thin nickel metal film.Floating glue cleans.
7) at Mn-PMNT wafer B face photolithography patterning.
8) at Mn-PMNT wafer B face deposit chromium gold layer, preparation extension electrode.Floating glue cleans.
9) at Mn-PMNT wafer B face photolithography patterning.
10) at Mn-PMNT wafer B face deposit chrome-nickel alloy film absorption layer.Floating glue cleans.
(2) heat dam between the photosensitive unit of preparation
11) at Mn-PMNT wafer B face photolithography patterning, form the heat dam etching mask.
12) adopt the method for argon ion etching to form heat dam between the photosensitive unit at Mn-PMNT wafer B face.
(3) attenuate Mn-PMNT wafer
13) the Mn-PMNT wafer is added hot melt wax from substrate and take off, clear first Mn-PMNT wafer is attached to the B face first on the white stone substrate, will be attached on the substrate with the Mn-PMNT wafer of white stone substrate again.The method of employing mechanical lapping is carried out attenuate and polishing to the A face of Mn-PMNT wafer, and thickness is 25 μ m.
(4) preparation bottom electrode
14) clean, at Mn-PMNT wafer A face photolithography patterning.
15) prepare chromium gold layer public electrode at Mn-PMNT wafer A face.
16) will take off with the dewaxing from the substrate of the Mn-PMNT wafer of substrate.Scribing is cleaned.
(5) photosensor chip and sensing circuit encapsulation
17) adopt epoxy glue bonding pyroelectricity photosensor chip and pyroelectricity photosensor chip substrate, form the photosensitive area hanging structure of self-supporting, at room temperature solidify.
18) with photosensor chip and sensing circuit Bonding, encapsulating package.
Claims (2)
1. non-refrigeration pyroelectricity Linear FPA, it comprises: pyroelectricity photosensor chip (1), photosensitive unit (2), extension electrode (3), bonding wire (4), sensing circuit input terminal electrode (5), readout circuit chip (6), public electrode (7), adhesive glue (8), pyroelectricity photosensor chip support substrates (9), pyroelectricity alignment substrate (10) and heat dam (11), it is characterized in that the focal plane structure is: be followed successively by pyroelectricity alignment substrate (10) and adhesive glue (8) from bottom to top; Pyroelectricity photosensor chip support substrates (9) at pyroelectricity alignment substrate left 1/3rd places, be bonded together by adhesive glue (8) and the pyroelectricity photosensor chip (1) above it, / 2nd of a unsettled chip width in pyroelectricity photosensor chip (1) left side, at the unsettled place of pyroelectricity photosensor chip lower surface deposit public electrode (7), upper surface deposit chromium nickel absorption layer is as photosensitive unit (2), and deposit chromium gold metallic film is as extension electrode (3); / 3rd places are readout circuit chip (6) on pyroelectricity alignment substrate right side, and the sensing circuit input terminal electrode (5) on it is by extension electrode (3) the connection coupling of bonding wire (4) with the pyroelectricity photosensor chip;
Described pyroelectricity photosensor chip (1) adopts Mn-(1-x) Pb (Mg
1/3Nb
2/3) O
3-xPbTiO
3(Mn-PMNT) relaxor ferroelectric monocrystal;
Described photosensitive unit (2) is the chrome-nickel alloy film;
Described extension electrode (3) is chromium gold metallic film;
Described bonding wire (4) is Si-Al wire;
Described sensing circuit input terminal electrode (6) is the aluminum metal film;
Described public electrode (7) is chromium gold metallic film;
Described adhesive glue (8) is epoxy glue;
Described pyroelectricity photosensor chip support substrates (9) adopts white stone;
Described pyroelectricity alignment substrate (10) is white stone.
2. manufacture method of non-refrigeration pyroelectricity Linear FPA as claimed in claim 1 is characterized in that step is as follows:
1) two of the Mn-PMNT wafer surfaces are labeled as respectively A face and B face.
2) the Mn-PMNT wafer of cleaning＜111〉direction polarization;
3) the A face with the Mn-PMNT wafer sticks on the substrate with wax, and Mn-PMNT wafer B face is carried out mechanical reduction and polishing;
4) the Mn-PMNT wafer is added hot melt wax from substrate and take off, clean the Mn-PMNT wafer, at room temperature with buffered hydrofluoric acid solution corrosion Mn-PMNT wafer B surface;
5) clean the Mn-PMNT wafer that has corroded, at B face photolithography patterning;
6) at Mn-PMNT wafer B face deposit chromium thin nickel metal film, floating glue cleans;
7) at Mn-PMNT wafer B face photolithography patterning;
8) at Mn-PMNT wafer B face deposit chromium gold layer, the preparation extension electrode, floating glue cleans;
9) at Mn-PMNT wafer B face photolithography patterning;
10) at Mn-PMNT wafer B face deposit chrome-nickel alloy film absorption layer, floating glue cleans;
11) at Mn-PMNT wafer B face photolithography patterning, form the heat dam etching mask;
12) adopt the method for argon ion etching to form heat dam between the photosensitive unit at Mn-PMNT wafer B face;
13) dewaxing from the substrate of Mn-PMNT wafer is taken off, clear first Mn-PMNT wafer, the B face is attached to first on the white stone substrate, will be attached on the substrate with the Mn-PMNT wafer of white stone substrate, the method for employing mechanical lapping is carried out attenuate and polishing to the A face of Mn-PMNT wafer;
14) clean, at Mn-PMNT wafer A face photolithography patterning;
15) prepare chromium gold layer public electrode at Mn-PMNT wafer A face;
16) will add hot melt wax from substrate with the Mn-PMNT wafer of substrate and take off, scribing is cleaned;
17) adopt epoxy glue bonding pyroelectricity photosensor chip and pyroelectricity photosensor chip substrate, form self-supporting photosensitive area hanging structure, at room temperature solidify;
18) with photosensor chip and sensing circuit Bonding, encapsulating package.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015172589A1 (en) * | 2014-05-12 | 2015-11-19 | 上海硅酸盐研究所中试基地 | Post-treatment method for pyroelectric relaxor ferroelectric single crystal |
| CN106601590A (en) * | 2016-12-20 | 2017-04-26 | 上海电机学院 | Wafer thinning process with low damage |
| CN108172502A (en) * | 2017-12-28 | 2018-06-15 | 南京理工大学 | Carrying wafer rapid thinning method applied to non-refrigerating infrared focal plane |
| CN111426399A (en) * | 2020-03-28 | 2020-07-17 | 无锡豪帮高科股份有限公司 | Production process of wireless temperature sensor based on thermopile |
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| US6133572A (en) * | 1998-06-05 | 2000-10-17 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Infrared detector system with controlled thermal conductance |
| CN101251422A (en) * | 2008-04-02 | 2008-08-27 | 中国科学院上海技术物理研究所 | Ultraviolet electricity scaling hot-dispelling electric detector |
| CN202885979U (en) * | 2012-11-01 | 2013-04-17 | 中国科学院上海技术物理研究所 | Uncooled pyroelectric linear array focal plane |
-
2012
- 2012-11-01 CN CN201210431102.XA patent/CN102928089B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6133572A (en) * | 1998-06-05 | 2000-10-17 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Infrared detector system with controlled thermal conductance |
| CN101251422A (en) * | 2008-04-02 | 2008-08-27 | 中国科学院上海技术物理研究所 | Ultraviolet electricity scaling hot-dispelling electric detector |
| CN202885979U (en) * | 2012-11-01 | 2013-04-17 | 中国科学院上海技术物理研究所 | Uncooled pyroelectric linear array focal plane |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015172589A1 (en) * | 2014-05-12 | 2015-11-19 | 上海硅酸盐研究所中试基地 | Post-treatment method for pyroelectric relaxor ferroelectric single crystal |
| CN106601590A (en) * | 2016-12-20 | 2017-04-26 | 上海电机学院 | Wafer thinning process with low damage |
| CN108172502A (en) * | 2017-12-28 | 2018-06-15 | 南京理工大学 | Carrying wafer rapid thinning method applied to non-refrigerating infrared focal plane |
| CN108172502B (en) * | 2017-12-28 | 2019-10-18 | 南京理工大学 | Carrying wafer rapid thinning method applied to non-refrigerating infrared focal plane |
| CN111426399A (en) * | 2020-03-28 | 2020-07-17 | 无锡豪帮高科股份有限公司 | Production process of wireless temperature sensor based on thermopile |
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