CN115425146A - Backside-illuminated microstructure array wide-spectrum imaging detector and preparation method thereof - Google Patents
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Abstract
The invention relates to a back-illuminated microstructure array wide-spectrum imaging detector and a preparation method thereof. The detector comprises a top end common electrode, a p-type microstructure array substrate and a graphical bottom electrode which are stacked from top to bottom, wherein the top end common electrode is deposited on the upper part of the p-type microstructure array substrate; and a p-type infrared light absorption material, an n-type electron transport window material and an n-type high-resistance semiconductor material are sequentially plated between the p-type microstructure array substrate and the patterned bottom electrode. The preparation method comprises the following steps: preparing a p-type microstructure array substrate: preparing an intermediate layer between the p-type microstructure array substrate and the patterned bottom electrode; preparing a graphical bottom electrode; a top common electrode was prepared. The invention improves the utilization rate of visible-infrared incident light, realizes the simultaneous acquisition of visible-infrared light signals by the vertical integrated device structure, widens the spectrum detection range of a single detector, is compatible with the conventional semiconductor preparation process, and has wide commercial application prospect.
Description
Technical Field
The invention belongs to the technical field of photoelectric detection, and particularly relates to a back-illuminated microstructure array wide-spectrum imaging detector.
Technical Field
The photoelectric detector is used as an important ring for photoelectric information acquisition and is widely applied to the aspects of vehicle driving, motion sensing, security alarm, infrared sensing imaging and the like. The photoelectric detection systems working in different wavelength regions have respective advantages in capability and use, but with the continuous development of science and technology, various emergency conditions and interference technologies appear, so that the requirements of users on the photoelectric detectors are higher and higher, and the photoelectric detectors only responding to a single waveband can not meet the actual requirements far away. How to efficiently acquire accurate multiband information in a complex environment becomes important, and therefore a photoelectric detection system with dual-band or multiband fusion is developed. However, the currently developed dual-band or multi-band detection system is usually assembled by two or more independent detection systems, and such a system has high manufacturing cost and an excessively large volume, which is contrary to the concept of high integration, miniaturization and light weight of the existing detection system.
CN201810862215 discloses "a wide-spectrum photoelectric detector based on amorphous nitride thin film and a preparation method thereof", and the technical problems exist as follows: the response spectrum range of the silicon detector is 350-1150nm, and the response spectrum is not widened remarkably compared with that of the traditional silicon detector (the response spectrum range of the traditional silicon detector is 400-1100 nm). In addition, the detector structure disclosed in CN201810862215 is a unit device, and the structure cannot satisfy the pixel isolation condition, and cannot form a focal plane imaging array. CN111739963B discloses a method for preparing a silicon-based wide spectrum photoelectric detector, which has the technical problems that: also its spectral response range (400-1600 nm) is much smaller than the present invention and pixel isolation is not possible. In addition, most of the related preparation methods of the light absorption layer materials are chemically synthesized, and the preparation consistency of the detector cannot be guaranteed.
Disclosure of Invention
The invention aims to provide a back-illuminated microstructure array wide-spectrum imaging detector and a preparation method thereof, and aims to solve the problems that the existing detector structure cannot meet the conditions of cross-band wide-spectrum detection and pixel isolation, cannot form a focal plane imaging array, and is lack of consistency in detector preparation.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a backside illuminated microstructure array wide-spectrum imaging detector: including top common electrode, p type microstructure array substrate and the graphical bottom electrode from top to bottom superpose, its characterized in that: the top common electrode is deposited on the upper part of the p-type microstructure array substrate; and a p-type infrared light absorption material, an n-type electron transport window material and an n-type high-resistance semiconductor material are sequentially plated between the p-type microstructure array substrate and the patterned bottom electrode.
Furthermore, the p-type microstructure array substrate is a columnar array structure arranged on a plane, the forbidden band width of the p-type microstructure array substrate is 1-1.5eV, the resistivity is 0.001-50 omega cm, the thickness is 100-200 μm, the diameter of the microstructure is 500nm-10 μm, the period is 1-20 μm, and the aspect ratio is 1-10.
Furthermore, the top common electrode is a full-coverage visible-infrared transparent conductive film electrode, specifically fluorine-doped indium tin oxide or aluminum-doped zinc oxide with a sheet resistance of 10-100 Ω.
Furthermore, the p-type infrared light absorption material is in a polycrystalline film or quantum dot film form, specifically is lead telluride, mercury cadmium telluride or lead tin tellurium, and has a thickness of 100nm-2 μm.
Furthermore, the n-type electron transport window material is an n-type semiconductor material, the forbidden band width is larger than 2eV, specifically cadmium sulfide, fullerene C60, fullerene C70 or C60MC12, and the thickness is 10-50nm.
Furthermore, the n-type high-resistance semiconductor material is an n-type wide-bandgap semiconductor material, the bandgap width is more than 3eV, and the n-type high-resistance semiconductor material is specifically tin oxide, gallium nitride or aluminum nitride, and the thickness is 0.2-2 μm.
Furthermore, the patterned bottom electrode is made of platinum, gold, silver or alloy electrode material, the resistivity is 0.001-10 omega cm, the thickness is 200nm-1 μm, and the electrode area is 1-100 μm 2 And the width of the inter-electrode isolation channel is 1-10 mu m.
Further, the preparation method of the back-illuminated microstructure array wide-spectrum imaging detector comprises the following steps:
step one, preparing a p-type microstructure array substrate: spin coating photoresist on the p-type substrate; according to the designed microstructure pattern, adopting a mask plate to carry out exposure treatment on the photoresist in the pattern region under ultraviolet light, then immersing the exposed sample wafer into a developing solution, removing the photoresist in the exposed part in the pattern region, and then carrying out hardening treatment on the sample wafer; processing the sample wafer after hardening by adopting plasma or chemical wet etching, and etching the substrate in the pattern area to a designed depth by controlling the etching rate to form a p-type microstructure array substrate;
step two, preparing an intermediate layer between the p-type microstructure array substrate and the patterned bottom electrode: spin-coating UV glue on the p-type microstructure array substrate to protect the microstructure; spin-coating a photoresist sacrificial layer on the back of the p-type microstructure array substrate; according to the designed sacrificial layer pattern, exposing the photoresist in the pattern region by using a mask under ultraviolet light, immersing the exposed sample wafer into a developing solution, and removing the photoresist at the exposed part in the pattern region; plating a p-type infrared light absorption material, an n-type electron transport window material and an n-type high-resistance semiconductor material on the back of the p-type microstructure array substrate in sequence, and removing the photoresist sacrificial layer;
step three, preparing a graphical bottom electrode: spin-coating a photoresist on the surface of an n-type high-resistance semiconductor material, adopting a mask to perform exposure treatment on the photoresist in a pattern region under ultraviolet light according to a designed bottom electrode pattern, then immersing an exposed sample wafer into a developing solution, removing the photoresist in the exposed part in the pattern region, and then performing hardening treatment on the sample wafer; depositing a bottom electrode material on the surface of the n-type high-resistance semiconductor material, and removing the redundant photoresist to form a patterned bottom electrode;
step four, preparing a top common electrode: and removing the UV protective glue on the upper surface of the p-type microstructure array substrate, preparing a top end common electrode on the p-type microstructure array substrate by adopting an atomic layer deposition technology, and finally finishing the preparation of the detector.
Compared with the prior art, the invention has the following advantages:
1. in the invention, visible-infrared light is incident to the surface of the p-type microstructure array substrate, and the visible light is absorbed by the p-type microstructure array substrate and converted into electron-hole pairs. The forbidden band width of the p-type microstructure array substrate is preferably 1-1.5eV, the thickness is preferably 100-200 μm, on one hand, the high-efficiency absorption of visible light is ensured, and the utilization rate of visible-infrared incident light is improved; on the other hand, this thickness provides good support for the device structure.
2. The light trapping effect of the microstructure can obviously enhance the absorption of visible light and reduce the reflection of infrared light, and the utilization rate of incident light is improved. The size of the microstructure can be flexibly designed to meet the requirements of different wave bands, and the microstructure has a wider application range. The p-type infrared light absorption material can flexibly select corresponding materials according to practical application conditions, and the universality of the structure of the detector designed by the invention is ensured.
3. The n-type electron transport window material plays a role in collecting and transporting electrons, and the thickness is preferably controlled to be 10-50nm, so that the increase of the electron recombination rate is avoided; the forbidden band width is larger than 2eV, and the generation of dark current can be inhibited under the premise of applying reverse bias. The n-type high-resistance semiconductor material is an n-type layer in a p-n junction, and the transverse high-resistance characteristic of the n-type high-resistance semiconductor material also plays a role in pixel isolation, so that focal plane array imaging is realized.
4. In the invention, the transparent conductive film is selected as the top end common electrode, so that the requirement on the transmittance of visible light and infrared light is met; on the other hand, the preparation method adopting the Atomic Layer Deposition (ALD) technology can realize the uniform wrapping of the surface of the electrode microstructure, and good full-coverage ohmic contact is formed.
5. The size of the detector unit pixel is determined by the area of a single graphical bottom electrode, an independent p-n junction unit is formed between the single graphical bottom electrode and a top end common electrode after external bias voltage is applied, the units are electrically isolated by n-type high-resistance semiconductor materials, an electric signal generated by each independent pixel unit is led out by a read-out circuit (ROIC), and a focal plane array image can be obtained after the electric signals of each pixel unit are collected and processed.
6. The invention can realize the wide spectrum detection of visible-infrared light of a single detector: the invention can flexibly adopt infrared absorption materials with different absorption wave bands, for example, pbTe infrared absorption materials, and the spectral response range of the detector is 400-2500nm; if HgCdTe is used, the spectral response range of the detector can encompass the entire visible-infrared region.
7. The vertical integrated device structure adopted by the invention realizes the simultaneous acquisition of visible-infrared light signals and widens the spectrum detection range of a single detector. The advantage of high gain output of the photovoltaic detector is obtained by longitudinally stacking the p-type light absorption material and the n-type high-resistance semiconductor material, the transverse high-resistance characteristic of the n-type high-resistance semiconductor material can ensure the electrical isolation among transverse pixels, and the imaging of the focal plane array can be realized by combining the patterned bottom electrode.
8. The preparation process of the invention is compatible with the existing semiconductor manufacturing process, the technical core lies in the shape regulation of the microstructure and the control of the uniformity and the components of each layer of film, but the processes are compatible with the existing semiconductor manufacturing process, and the preparation equipment can adopt the existing mature equipment, so the consistency of the device preparation can be effectively ensured, the preparation cost is low, and the invention is suitable for industrial production.
Description of the drawings:
FIG. 1 is a schematic structural diagram of a backside illuminated microstructure array broad spectrum imaging detector;
FIG. 2 is a schematic diagram of the operation of a backside illuminated microstructure array broad spectrum imaging detector;
FIG. 3 is a flow chart of a fabrication process for a backside illuminated micro-structured array wide-spectrum imaging detector;
FIG. 4 is an absorption spectrum of the detector prepared in example 1;
FIG. 5 is a graph showing the response of the detector prepared in example 1 at 2200 nm.
Description of the labeling: 1-top shared electrode, 2-p type microstructure array substrate, 3-p type infrared light absorption material, 4-n type electron transport window material, 5-n type high resistance semiconductor material, and 6-patterned bottom electrode.
The specific implementation mode is as follows:
in order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1: a backside illuminated microstructure array wide-spectrum imaging detector comprises a p-type microstructure array substrate 2, wherein a top end common electrode 1 is arranged on the p-type microstructure array substrate 2, and a p-type infrared light absorption material 3, an n-type electron transportation window material 4, an n-type high-resistance semiconductor material 5 and a patterned bottom electrode 6 are sequentially plated on the back surface of the p-type microstructure array substrate 2.
The size of the microstructure can be flexibly designed, for example, aiming at enhancing visible light absorption, the size of the microstructure can be designed to be 500nm in diameter, 1 μm in period and 5 in aspect ratio; if the infrared absorption needs to be enhanced, the size of the microstructure can be adjusted according to the corresponding wave bands (near infrared, medium wave infrared and long wave infrared).
The p-type infrared light absorption material can flexibly select corresponding materials according to actual application conditions, and PbTe can be selected in a near infrared band (800-2500 nm); hgCdTe or PbSnTe can be selected in the medium-wave infrared (3-5 μm) and long-wave infrared (8-12 μm) wave bands.
The p-type microstructure array substrate 2 is a columnar array structure arranged on a plane, and has the forbidden band width of 1-1.5eV, the resistivity of 0.001-50 omega cm, the thickness of 100-200 μm, the microstructure diameter of 500nm-10 μm, the period of 1-20 μm and the height-width ratio of 1-10.
The top common electrode 1 can be a full-coverage visible-infrared transparent conductive film electrode, such as: fluorine-doped indium tin oxide (FTO), aluminum-doped zinc oxide (AZO) and the like, and the sheet resistance is 10-100 omega.
The p-type infrared light absorbing material 3 can be in a polycrystalline film or quantum dot film form, and can adopt lead telluride (PbTe), mercury cadmium telluride (HgCdTe), lead tin tellurium (PbSnTe) and the like, and the thickness is 100nm-2 μm.
The n-type electron transport window material 4 can be an n-type semiconductor material, and the forbidden band width is greater than 2eV, for example: cadmium sulfide (CdS), fullerene (C60, C70), C60MC12 and the like, and the thickness is 10-50nm.
1. The n-type high-resistance semiconductor material 5 can be an n-type wide bandgap semiconductor material, the bandgap width is greater than 3eV, for example: tin oxide (SnO) 2 ) Gallium nitride (GaN), aluminum nitride (AlN), etc., in a thickness of 0.2-2 μm.
The patterned bottom electrode 6 can be made of platinum (Pt), gold (Au), silver (Ag) or alloy electrode material, etc., and has resistivity of 0.001-10 Ω & cm, thickness of 200nm-1 μm, and electrode area of 1-100 μm 2 The inter-electrode isolation channel width is 1-10 μm.
Example 1: the method comprises the following steps of (1) adopting a double-polished silicon wafer as a p-type microstructure array substrate, wherein the resistivity is 10 omega cm, the thickness is 100 micrometers, the diameter of a microstructure is 2 micrometers, the period is 4 micrometers, and the aspect ratio is 5; the top common electrode adopts indium-doped tin oxide (ITO) with the square resistance of 10 omega; the p-type infrared light absorption material adopts lead telluride (PbTe) with the thickness of 500nm; the n-type electron transport window material adopts cadmium sulfide (CdS) with the thickness of 20nm; the n-type high-resistance semiconductor material adopts gallium nitride (GaN) with the thickness of 200nm; the patterned bottom electrode is made of platinum (Pt), the resistivity is 0.1 omega cm, the thickness is 200nm, the side length is 5 mu m, the width of the inter-electrode isolation channel is 1 mu m, and the electrode pattern is square.
Example 2: double-polishing indium phosphide (InP) is used as a p-type microstructure array substrate, the resistivity is 15 omega cm, the thickness is 200 mu m, the microstructure diameter is 5 mu m, the period is 10 mu m, and the aspect ratio is 8; the top end common electrode adopts aluminum-doped zinc oxide (AZO), and the sheet resistance is 15 omega; the p-type infrared light absorbing material adopts mercury cadmium telluride (HgCdTe) with the thickness of 1 mu m; the n-type electron transport window material adopts fullerene (C60) with the thickness of 10nm; the n-type high-resistance semiconductor material adopts aluminum nitride (AlN) with the thickness of 500nm; the patterned bottom electrode is made of gold (Au), the resistivity is 0.01 omega cm, the thickness is 500nm, the side length is 10 mu m, the width of the inter-electrode isolation channel is 5 mu m, and the electrode pattern is square.
Referring to fig. 2: the back-illuminated microstructure array wide-spectrum imaging detector has the working principle that: visible light and infrared light are incident on the surface of the p-type microstructure array substrate 2, and the visible light is absorbed by the p-type microstructure array substrate 2 and converted into electron-hole pairs. The infrared light penetrates the p-type microstructure array substrate 2 and is absorbed by the p-type infrared light absorption material 3, and is converted into electron-hole pairs. The n-type electron transport window material 4 plays a role in collecting and transporting electrons, and can also inhibit the generation of dark current under the premise of applying reverse bias. The n-type high-resistance semiconductor material 5 is not only an n-type layer in a p-n junction, but also plays a role in pixel isolation. And a negative voltage is applied to the top end common electrode 1, a positive voltage is applied to the patterned bottom electrode 6, and the electron-hole pairs generated by the visible light and the infrared light are separated under the action of an electric field built in a p-n junction of the whole device and an external reverse bias voltage to form photocurrent, so that the wide-spectrum detection of the visible light and the infrared light is realized. The current signal is derived by a read-out circuit (ROIC) and converted into image information.
Referring to fig. 3: the preparation process flow of the back-illuminated microstructure array wide-spectrum imaging detector comprises the following steps:
step one, spin-coating photoresist on a p-type doped silicon or germanium sheet; according to the designed microstructure pattern, adopting a mask plate to carry out exposure treatment on the photoresist in the pattern region under ultraviolet light, then immersing the exposed sample wafer into a developing solution, removing the photoresist in the exposed part in the pattern region, and then carrying out hardening treatment on the sample wafer; and processing the hardened sample wafer by adopting plasma or chemical wet etching, and etching the substrate in the pattern area to a designed depth by controlling the etching rate to form the p-type microstructure array substrate 2.
Step two, preparing an intermediate layer between the p-type microstructure array substrate 2 and the patterned bottom electrode 6: spin-coating UV glue on the p-type microstructure array substrate 2 to protect the microstructure; spin-coating a photoresist sacrificial layer on the back of the p-type microstructure array substrate 2; according to the designed sacrificial layer pattern, exposing the photoresist in the pattern region by using a mask under ultraviolet light, immersing the exposed sample wafer into a developing solution, and removing the photoresist at the exposed part in the pattern region; a p-type infrared light absorbing material 3, an n-type electronic transportation window material 4 and an n-type high-resistance semiconductor material 5 are sequentially plated on the back surface of a p-type microstructure array substrate 2 by means of thermal evaporation, magnetron sputtering, ion beam sputtering, atomic layer deposition, continuous ion layer deposition, quantum dot spin coating or a sol-gel method and the like, and the photoresist sacrificial layer is removed. In this example, a thermal evaporation method was used.
Step three, preparing a patterned bottom electrode 6: spin-coating photoresist on the surface of the n-type high-resistance semiconductor material 5; according to the designed bottom electrode pattern, adopting a mask plate to carry out exposure treatment on the photoresist in the pattern region under ultraviolet light, then immersing the exposed sample wafer into a developing solution, removing the photoresist in the exposed part in the pattern region, and then carrying out film hardening treatment on the sample wafer; and depositing a bottom electrode material on the surface of the n-type high-resistance semiconductor material (5) by methods such as thermal evaporation, magnetron sputtering, ion beam sputtering and the like, and removing the redundant photoresist to form a patterned bottom electrode 6. In this example, a magnetron sputtering method was used.
Step four, preparing a top end common electrode 1: and removing the UV protective glue on the upper surface of the p-type microstructure array substrate 2, and preparing the top common electrode 1 thereon by adopting an Atomic Layer Deposition (ALD) method.
Referring to fig. 4: in example 1, the absorption rate of the p-type silicon substrate is significantly reduced after 1100nm, the light absorption is almost cut off, the light absorption rate is far lower than that of the other two structures, the absorption rate in the visible-near infrared region of the p-type silicon substrate with the light trapping microstructure is significantly increased, the light absorption rate of the device is further improved along with the recombination of the PbTe infrared absorption layer, and the spectral range covers the 400-2500nm waveband.
Referring to fig. 5: the photoelectric response of the detector prepared in example 1 under the test of 2200nm light source is 10.517 muA/W and 2.23 multiplied by 10 under-0.5V bias 7 Jones. Effectively broadens the spectral response range and successfully breaks through the wavelength limit of 1100 nm.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.
Claims (8)
1. A backside illuminated microstructure array wide spectrum imaging detector is characterized in that: the device comprises a top end common electrode (1) stacked from top to bottom, a p-type microstructure array substrate (2) and a graphical bottom electrode (6), and is characterized in that: the top end common electrode (1) is deposited on the upper part of the p-type microstructure array substrate (2); and a p-type infrared light absorption material (3), an n-type electron transport window material (4) and an n-type high-resistance semiconductor material (5) are sequentially plated between the p-type microstructure array substrate (2) and the patterned bottom electrode (6).
2. The back-illuminated micro-structured array broad spectrum imaging detector according to claim 1, wherein: the p-type microstructure array substrate (2) is a columnar array structure arranged on a plane, the forbidden band width of the p-type microstructure array substrate is 1-1.5eV, the resistivity is 0.001-50 omega cm, the thickness is 100-200 mu m, the diameter of the microstructure is 500nm-10 mu m, the period is 1-20 mu m, and the height-width ratio is 1-10.
3. The backside illuminated micro-structure array broad spectrum imaging detector of claim 2, wherein: the top end common electrode (1) is a full-coverage visible-infrared transparent conductive film electrode, specifically fluorine-doped indium tin oxide or aluminum-doped zinc oxide, and the sheet resistance is 10-100 omega.
4. The back-illuminated micro-structured array broad spectrum imaging detector according to claim 3, wherein: the p-type infrared light absorption material (3) is in a polycrystalline film or quantum dot film form, specifically is lead telluride, mercury cadmium telluride or lead tin tellurium, and has a thickness of 100nm-2 μm.
5. The backside illuminated micro-structure array broad spectrum imaging detector of claim 4, wherein: the n-type electron transport window material (4) is an n-type semiconductor material, the forbidden band width is larger than 2eV, specifically cadmium sulfide, fullerene C60, fullerene C70 or C60MC12, and the thickness is 10-50nm.
6. The back-illuminated micro-structured array broad spectrum imaging detector according to claim 5, wherein: the n-type high-resistance semiconductor material (5) is an n-type wide-bandgap semiconductor material, the bandgap width is more than 3eV, and the n-type high-resistance semiconductor material is specifically tin oxide, gallium nitride or aluminum nitride and has the thickness of 0.2-2 μm.
7. The back-illuminated micro-structured array broad spectrum imaging detector according to claim 6, wherein: the patterned bottom electrode (6) is made of platinum, gold, silver or alloy electrode material, the resistivity is 0.001-10 omega cm, the thickness is 200nm-1 mu m, and the electrode area is 1-100 mu m 2 And the width of the inter-electrode isolation channel is 1-10 mu m.
8. The method for preparing the backside illuminated micro-structure array broad spectrum imaging detector according to claim 1, comprising the following steps:
step one, preparing a p-type microstructure array substrate (2): spin coating photoresist on the p-type substrate; according to the designed microstructure pattern, adopting a mask plate to carry out exposure treatment on the photoresist in the pattern region under ultraviolet light, then immersing the exposed sample wafer into a developing solution, removing the photoresist in the exposed part in the pattern region, and then carrying out hardening treatment on the sample wafer; processing the sample wafer after hardening by adopting plasma or chemical wet etching, and etching the substrate in the pattern area to a designed depth by controlling the etching rate to form a p-type microstructure array substrate (2);
step two, preparing an intermediate layer between the p-type microstructure array substrate (2) and the patterned bottom electrode (6): spin-coating UV glue on the p-type microstructure array substrate (2) to protect the microstructure; spin-coating a photoresist sacrificial layer on the back of the p-type microstructure array substrate (2); according to the designed sacrificial layer pattern, exposing the photoresist in the pattern region by using a mask under ultraviolet light, immersing the exposed sample wafer into a developing solution, and removing the photoresist at the exposed part in the pattern region; plating a p-type infrared light absorption material (3), an n-type electron transport window material (4) and an n-type high-resistance semiconductor material (5) on the back of the p-type microstructure array substrate (2) in sequence, and removing the photoresist sacrificial layer;
step three, preparing a graphical bottom electrode (6): spin-coating a photoresist on the surface of the n-type high-resistance semiconductor material (5), adopting a mask to perform exposure treatment on the photoresist in a pattern region under ultraviolet light according to a designed bottom electrode pattern, then immersing an exposed sample wafer into a developing solution, removing the photoresist at the exposed part in the pattern region, and then performing hardening treatment on the sample wafer; depositing a bottom electrode material on the surface of the n-type high-resistance semiconductor material (5), and removing the redundant photoresist to form a patterned bottom electrode (6);
step four, preparing a top end common electrode (1): and removing the UV protective glue on the upper surface of the p-type microstructure array substrate (2), preparing a top end common electrode (1) on the p-type microstructure array substrate by adopting an atomic layer deposition technology, and finally finishing the preparation of the detector.
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| US20120223291A1 (en) * | 2009-09-29 | 2012-09-06 | Research Triangle Institute, International | Quantum dot-fullerene junction based photodetectors |
| CN103400887A (en) * | 2013-08-08 | 2013-11-20 | 电子科技大学 | Backside illuminated Si-PIN photoelectric detector and preparation method thereof |
| KR20210004536A (en) * | 2019-07-05 | 2021-01-13 | 포항공과대학교 산학협력단 | Vertical nanowire based photodetector having double absorption layer and manufacturing method thereof |
| US11251209B1 (en) * | 2013-03-15 | 2022-02-15 | Hrl Laboratories, Llc | Reduced volume dual-band MWIR detector |
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| US20120223291A1 (en) * | 2009-09-29 | 2012-09-06 | Research Triangle Institute, International | Quantum dot-fullerene junction based photodetectors |
| US11251209B1 (en) * | 2013-03-15 | 2022-02-15 | Hrl Laboratories, Llc | Reduced volume dual-band MWIR detector |
| CN103400887A (en) * | 2013-08-08 | 2013-11-20 | 电子科技大学 | Backside illuminated Si-PIN photoelectric detector and preparation method thereof |
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