Strong-light-resistant PIN-type laminated laser detector and manufacturing method thereof

Abstract

The invention relates to a strong-light-resistant PIN type laminated laser detector and a manufacturing method, and belongs to the field of photoelectric detector chips. The detector comprises two stacked sub-detectors, wherein the sub-detector I is arranged at the upper part and comprises a P + contact region I, an i absorption region I, an N + contact region I, an antireflection film, an electrode I, a dielectric layer I and an electrode II; the sub-detector II is arranged at the lower part and comprises a P + contact region II, an i absorption region II, an N + contact region II, a dielectric layer II and an electrode III; a filter film I is arranged on the sub-detector II; a bonding layer is arranged on the filter film I and is connected with the sub-detector I and the sub-detector II; the electrode II and the electrode III are provided with through holes so as to be interconnected with a peripheral circuit. The system has excellent strong sunlight interference resistance, and high fidelity of signal detection is ensured at the same time.

Description

Technical Field

[0001] This invention belongs to the field of photodetector chips and relates to a PIN-type stacked laser detector resistant to strong light and its manufacturing method. Background Technology

[0002] Laser detectors measure targets by detecting the echo signal from a laser beam illuminating the target object. The detector is typically connected in series with a sampling resistor and extracts the AC signal through a DC blocking capacitor. When the detector receives light, it generates a photocurrent, which flows through the sampling resistor and is converted into a voltage signal. The DC component of the voltage signal is filtered out by the DC blocking capacitor, allowing only the AC component to enter the downstream circuitry. However, when the laser detector is exposed to strong sunlight, the intense sunlight causes it to output a very large photocurrent. This large current causes the voltage across the sampling resistor to rise rapidly, resulting in a significant drop in the voltage difference across the detector. This causes the detector to deviate considerably from its optimal operating voltage, rendering it unable to function properly.

[0003] Patent application CN119653881A discloses a laser detector suitable for strong sunlight environments and its fabrication method. It involves arranging two identical sub-detectors in parallel and setting different filters at their front ends to ensure that the sunlight entering the two sub-detectors is the same, followed by differential cancellation of sunlight current. However, when the system containing the detector has an optical lens, sunlight is focused onto the detector as a bright spot, making it difficult to distribute evenly on the photosensitive surfaces of the two sub-detectors, thus failing to eliminate sunlight current. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a PIN-type stacked laser detector resistant to strong light and a manufacturing method thereof, so as to solve the problem that existing laser detectors cannot work properly in strong sunlight environments.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] Option 1: A PIN-type stacked laser detector resistant to strong light, comprising two stacked sub-detectors; wherein, one sub-detector I is placed on top, including P + Contact area I, located at P + The i-absorption region I above the contact region I, and N above the i-absorption region I. + Contact area I, located at N + An antireflection coating above contact area I, electrode I disposed above the antireflection coating, and electrode I disposed at P. + Dielectric layer I beneath contact region I, electrode II disposed beneath dielectric layer I; P + Contact area I and electrode II are in contact through contact holes on dielectric layer I; N + Contact area I is in contact with electrode I through contact holes on the antireflection membrane.

[0007] Another sub-detector II is placed below, including P + Contact area II, located at P + The i-absorption region II above the contact region II, and the N-type absorption region II above the i-absorption region II. + Contact area II, located at N + A dielectric layer II above the contact area II, and an electrode III disposed above the dielectric layer II; the N + Contact area II and electrode III are in contact through contact holes on dielectric layer II; the P + Contact area II is in contact with electrode IV.

[0008] A filter film I is disposed on top of sub-detector II; a bonding layer is disposed on filter film I to connect sub-detector I and sub-detector II; through holes are disposed on electrodes II and III to interconnect with external circuits.

[0009] The detector is encapsulated in a tube, with an optical window on top of the tube, and a filter film II is installed on top of the optical window; during encapsulation, electrode II and electrode III are short-circuited.

[0010] Preferably, the thickness of sub-detector I is less than the thickness of sub-detector II.

[0011] Preferably, the bonding layer is able to transmit incident light.

[0012] Preferably, the antireflective membrane is a broadband antireflective membrane.

[0013] Preferably, filter film I is characterized by having a high reflectivity in the wavelength band corresponding to the laser signal and a very low reflectivity outside the wavelength band corresponding to the laser signal.

[0014] Preferably, the filter film II is a bandpass filter film, the starting wavelength of its passband width is determined by the signal light wavelength, and the cutoff wavelength is determined by the detector design.

[0015] Preferably, taking advantage of the characteristic that longer incident light wavelengths penetrate deeper into the detector, most of the long-wavelength light in sunlight penetrates sub-detector I and enters sub-detector II. When the photocurrents generated by sunlight in sub-detector I and sub-detector II are equal, the sunlight current can be eliminated; at the same time, filter film I is used to prevent signal light from entering sub-detector II, thus avoiding affecting the signal photocurrent when eliminating the sunlight current.

[0016] Filter I needs to have high reflectivity in the λ0-λ1 to λ0+λ1 band and low reflectivity in the band after λ0+λ1; λ0±λ1 is the wavelength range of the signal light. Filter film II needs to meet the requirements of λ0-λ1 to λ n Low reflectivity in one band, high reflectivity in other bands; where λ n The value of satisfies that the incident light wavelength range is from λ0-λ1 to λ nAt that time, the photocurrents of sub-detector I and sub-detector II were basically the same.

[0017] Option 2: A method for manufacturing a PIN-type stacked laser detector resistant to strong light, the specific process of which is as follows: (1) Prepare a clean P-type epitaxial silicon wafer; (2) The P of the sub-detector I is formed by photolithography. + Contact area I pattern, and P formed by high-dose boron injection. + Contact area I; (3) Deposition medium layer I; (4) Etch contact holes in dielectric layer I; (5) Electrode II is formed by depositing metallic aluminum on the front side and then sequentially through photolithography and etching; (6) Flip the epitaxial silicon wafer so that the front side is down and the back side is up, in preparation for bonding; (7) Prepare a clean P-type monocrystalline silicon wafer; (8) The N-type sub-detector II is formed by photolithography. + Contact area II pattern, and N formed by injecting a large dose of phosphorus. + Contact area II; (9) Deposition medium layer II; (10) Etch contact holes in dielectric layer II; (11) Metallic aluminum is deposited on the front side, and electrode III is formed by photolithography and etching; (12) Filter film I is deposited on the front side; (13) The front side of the epitaxial silicon wafer containing sub-detector I is bonded to the front side of the single-crystal silicon wafer containing sub-detector II through a bonding layer; (14) The low resistivity substrate of the epitaxial silicon wafer is removed by mechanical polishing and self-stopping etching in sequence; (15) The N-type sub-detector I is formed by photolithography. + Contact area I pattern, and N is formed by injecting a large dose of phosphorus. + Contact area I; (16) Deposition of antireflective membrane; (17) Etch contact holes in the antireflection film; (18) Deposit metallic aluminum and form electrode I by photolithography and etching in sequence; (19) Thinning of single-crystal silicon wafers is achieved by first mechanically grinding and then polishing; (20) The P of the sub-detector II was formed by injecting a large dose of boron. + Contact area II; (21) Deposit metallic aluminum to form electrode IV; (22) Through holes corresponding to electrode II and electrode III are formed sequentially by photolithography and deep silicon etching.

[0018] Furthermore, when fabricating this detector for the first time, it needs to be calibrated using filter II on the optical window of the tube shell. The procedure is as follows: (1) The detector is encapsulated in a tube shell, but the light window is not sealed; (2) Using a simulated solar light source, the output current of the two sub-detectors at different wavelengths was tested respectively; (3) Starting from wavelength λ0-λ1, measure and record the output current values ​​of the two sub-detectors every 10nm; (4) The output current values ​​of sub-detector I and sub-detector II at different wavelengths are summed up respectively. Since the longer the wavelength, the larger the photocurrent of sub-detector II is relative to sub-detector I, there must be a wavelength λ n This ensures that the accumulated currents of the two sub-detectors are basically the same; (5) A filter film II is deposited on the optical window, characterized in that it can only transmit wavelengths from λ0-λ1 to λ n The light; (6) Seal the light window with filter film II onto the tube shell.

[0019] The beneficial effects of this invention are as follows: By adopting a PIN-type stacked structure design and combining it with a specific filter film configuration, this solution brings the following specific beneficial effects: (1) It has excellent resistance to strong sunlight interference. In principle, it achieves current cancellation. Specifically, it uses Kirchhoff's current law to short-circuit the electrodes of the upper and lower sub-detectors. By adjusting, the sunlight current generated by the upper sub-detector (receiving sunlight + signal) is equal to the sunlight current generated by the lower sub-detector (mainly receiving transmitted long-wave sunlight), thus achieving mutual cancellation of sunlight currents in electrical terms, retaining only the signal current. Since the large DC current generated by sunlight is eliminated, the detector will not deviate from the optimal operating voltage due to excessive voltage division of the sampling resistor, ensuring that it can still detect laser signals normally under strong light.

[0020] (2) Unlike the parallel arrangement, this scheme adopts a vertical stacking structure (sub-detector I is located above sub-detector II). Taking advantage of the deep penetration of long-wavelength light, even if sunlight is focused into a bright spot by the lens, the beam can naturally pass through the upper layer and enter the lower layer without being evenly distributed on the plane, thus completely solving the problem of sunlight elimination in lens systems.

[0021] (3) High fidelity of signal detection. This scheme adopts a selective filtering design, and a filter film I is set between the two sub-detectors. This film has high reflectivity in the laser signal band, which prevents the signal light from entering the lower sub-detector and avoids the accidental deletion of the signal current when the sunlight current is differentially eliminated, thus ensuring the complete output of the laser signal.

[0022] (4) Flexible adjustability. This scheme uses a filter film II on the optical window of the tube shell and determines the cutoff wavelength λ according to the detector design. n Since longer wavelengths result in greater photocurrent in the lower-level detector, this can be addressed by adjusting λ. n This ensures that the cumulative current from sunlight collected by the two sub-detectors is essentially the same, thus achieving the optimal cancellation effect.

[0023] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0024] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a schematic diagram of a PIN-type stacked laser detector structure resistant to strong sunlight according to an embodiment of the present invention.

[0025] Figure 2 This is a schematic diagram of the optical principle of the detector in an embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the reflectance of filter film I of the detector in an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the reflectance of filter film II of the detector in an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the electrical principle of the detector in an embodiment of the present invention.

[0029] Figure 6 This is a process flow diagram of the detector in an embodiment of the present invention.

[0030] Figure 7 This is an IV curve diagram of the detector in an embodiment of the present invention. Detailed Implementation

[0031] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0032] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0033] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0034] Example 1: This embodiment provides a PIN-type stacked laser detector resistant to strong sunlight, such as Figure 1 As shown, its structure includes two stacked sub-detectors. Among them, A sub-detector I is placed above, including P + Contact area I, located at P + The i-absorption region I above the contact region I, and N above the i-absorption region I. + Contact area I, located at N + An antireflection coating above contact area I, electrode I disposed above the antireflection coating, and electrode I disposed at P. + Dielectric layer I beneath contact region I, electrode II disposed beneath dielectric layer I; P + Contact area I and electrode II are in contact through contact holes on dielectric layer I; N + Contact area I is in contact with electrode I through contact holes on the antireflection membrane.

[0035] Another sub-detector II is placed below, including P+ Contact area II, located at P + The i-absorption region II above the contact region II, and the N-type absorption region II above the i-absorption region II. + Contact area II, located at N + A dielectric layer II above the contact area II, and an electrode III disposed above the dielectric layer II; the N + Contact area II and electrode III are in contact through contact holes on dielectric layer II; the P + Contact area II is in contact with electrode IV.

[0036] A filter film I is disposed on top of sub-detector II; a bonding layer is disposed on filter film I to connect sub-detector I and sub-detector II; through holes are disposed on electrodes II and III to interconnect with external circuits.

[0037] The detector is encapsulated in a tube, with an optical window on top of the tube, and a filter film II is installed on top of the optical window; during encapsulation, electrode II and electrode III are short-circuited.

[0038] The thickness of sub-detector I is less than the thickness of sub-detector II.

[0039] The antireflective coating is a broadband antireflective coating. The bonding layer is characterized by its ability to transmit incident light.

[0040] Filter I is characterized by its high reflectivity within the wavelength band corresponding to the laser signal and its low reflectivity outside that band. Filter II is a bandpass filter, characterized by its passband width starting wavelength being determined by the signal light wavelength and its cutoff wavelength being determined by the detector design.

[0041] The optical principle of the detector is as follows: Figure 2 As shown. Utilizing the property that longer incident light wavelengths penetrate deeper into the detector, most of the long-wavelength sunlight is allowed to penetrate sub-detector I and enter sub-detector II. When the photocurrents generated by sunlight in sub-detector I and sub-detector II are equivalent, the sunlight current can be eliminated. Simultaneously, filter I prevents signal light from entering sub-detector II, avoiding interference with the signal photocurrent during sunlight current elimination. Therefore, if the signal light wavelength range is λ0±λ1, filter I must satisfy the following requirements: high reflectivity in the λ0-λ1 to λ0+λ1 band and low reflectivity in the band after λ0+λ1. Figure 3 As shown; filter film II needs to meet the requirements from λ0-λ1 to λ n The reflectivity is low in one band and high in other bands, such as... Figure 4 As shown. Where, λ n The value of λ is determined by the detector design. Since the longer the wavelength, the larger the photocurrent of sub-detector II relative to sub-detector I, there must exist a wavelength λ... n The incident light wavelength range is λ0-λ1 to λ n At that time, the photocurrents of sub-detector I and sub-detector II were basically the same.

[0042] The electrical principle of the detector is as follows: Figure 5 As shown. Electrode 2 of sub-detector I is short-circuited to electrode 3 of sub-detector II and grounded through a sampling resistor. According to Kirchhoff's current law, the algebraic sum of the currents flowing into any node of the circuit is zero. For node V0, the inflow current is the sunlight current I generated by sub-detector I and the laser current, and the outflow current is the sunlight current I generated by sub-detector II and the sampling current flowing through the sampling resistor. That is: sunlight current I + laser current = sunlight current II + sampling current. When the wavelength λ is set appropriately... n When the sunlight current I and sunlight current II are equal, the sampling current equals the laser current. At this point, the photocurrent generated by sunlight is eliminated and no longer affects the detection of the laser signal by the stacked detector.

[0043] Example 2: like Figure 6 As shown in Example 1, the main manufacturing process of the PIN-type stacked laser detector resistant to strong sunlight is as follows: (1) Prepare a clean P-type epitaxial silicon wafer with an epitaxial layer resistivity ≥100Ωcm; an epitaxial layer thickness of 20μm (the epitaxial layer thickness depends on the wavelength of the laser signal); and a substrate resistivity of 0.01~0.05Ωcm. (2) The P of the sub-detector I is formed by photolithography. + Contact area I pattern, and P formed by high-dose boron injection. + Contact area I, preferably P + The concentration range of contact zone I is 1E18cm. -3 ~1E20cm -3 ; (3) Deposit dielectric layer I, preferably silicon oxide, which serves as a surface passivation material; (4) Etch contact holes in dielectric layer I; (5) Electrode II is formed by depositing metallic aluminum on the front side and then photolithography and etching. (6) Flip the epitaxial silicon wafer so that the front side is down and the back side is up, in preparation for bonding; (7) Prepare a clean P-type single crystal silicon wafer with a resistivity ≥1000Ωcm; (8) The N-type sub-detector II is formed by photolithography. + Contact area II pattern, and N formed by injecting a large dose of phosphorus. + Contact area II, preferably N + The concentration range of contact zone II is 1E18cm. -3 ~1E20cm -3 ; (9) Deposit dielectric layer II, preferably silicon oxide, which serves as a surface passivation material; (10) Etch contact holes in dielectric layer II; (11) Metallic aluminum is deposited on the front side, and electrode III is formed by photolithography and etching; (12) A filter film I is deposited on the front side. The filter film has a high reflectivity in the corresponding wavelength band of the laser signal and a low reflectivity outside the corresponding wavelength band of the laser signal. (13) The front side of the epitaxial silicon wafer containing sub-detector I is bonded to the front side of the single-crystal silicon wafer containing sub-detector II through a bonding layer. The bonding layer is transparent to incident light. The bonding layer material can be a polymer adhesive or silicon oxide; (14) The low resistivity substrate of the epitaxial silicon wafer is removed by mechanical polishing and self-stopping etching. Preferably, the remaining substrate thickness after mechanical polishing is 50μm~80μm; the preferred self-stopping etching solution consists of nitric acid, hydrofluoric acid and glacial acetic acid, and automatically stops after etching by utilizing the difference in etching rate of silicon materials with different doping concentrations.

[0044] (15) The N-type sub-detector I is formed by photolithography. + Contact area I pattern, and N is formed by injecting a large dose of phosphorus. + Contact area I, preferably N + The concentration range of contact zone I is 1E18cm. -3 ~1E20cm -3 .

[0045] (16) Deposition of antireflective membrane; (17) Etch contact holes in the antireflection film; (18) Deposit metallic aluminum and form electrode I through photolithography and etching; (19) The single-crystal silicon wafer was thinned to 300μm by first mechanical grinding and then polishing; (20) The P of the sub-detector II was formed by injecting a large dose of boron. + Contact area II, preferably P + The concentration range of contact zone II is 1E18cm. -3 ~1E20cm -3 ; (21) Deposit metallic aluminum to form electrode IV; (22) Through holes corresponding to electrodes II and III are formed by photolithography and deep silicon etching.

[0046] When fabricating a PIN-type multilayer laser detector resistant to strong sunlight for the first time, calibration is required through filter film 2 on the optical window of the tube shell. The process is as follows: (1) The detector is encapsulated in a tube shell, but the light window is not sealed; (2) Using a simulated solar light source, the output current of the two sub-detectors at different wavelengths was tested respectively; (3) Starting from wavelength λ0-λ1, measure and record the output current values ​​of the two sub-detectors every 10nm; (4) The output current values ​​of sub-detector I and sub-detector II at different wavelengths are summed up respectively. Since the longer the wavelength, the larger the photocurrent of sub-detector II is relative to sub-detector I, there must be a wavelength λ n This ensures that the accumulated currents of the two sub-detectors are basically the same; (5) A filter film II is deposited on the optical window, characterized in that it can only transmit wavelengths from λ0-λ1 to λ n The light; (6) Seal the light window with filter film II onto the tube shell.

[0047] Figure 7 This is an example of an IV curve of the detector under simulated sunlight. A 5V voltage is applied to sub-detector I, and then the voltage of sub-detector II is gradually increased. During this process, due to the widening of the depletion region of sub-detector II, the output photocurrent increases, and the difference between the output photocurrents of sub-detector I and sub-detector II decreases. Therefore, the current output from electrode II / electrode III gradually decreases, reaching a minimum of approximately 30nA when the voltage reaches 43V. When the voltage is further increased, the output current of sub-detector II surpasses that of sub-detector I, and the current output from electrode II / electrode III gradually increases.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A PIN-type stacked laser detector resistant to strong light, characterized in that, It includes two stacked sub-detectors; among which, A sub-detector I is placed above, including P + Contact area I, located at P + The i-absorption region I above the contact region I, and N above the i-absorption region I. + Contact area I, located at N + An antireflection coating above contact area I, electrode I disposed above the antireflection coating, and electrode I disposed at P. + A dielectric layer I beneath contact region I, and an electrode II disposed beneath dielectric layer I; the P + Contact area I and electrode II are in contact through contact holes on dielectric layer I; the N + Contact area I is in contact with electrode I through contact holes on the antireflection membrane; Another sub-detector II is placed below, including P + Contact area II, located at P + The i-absorption region II above the contact region II, and the N-type absorption region II above the i-absorption region II. + Contact area II, located at N + A dielectric layer II above the contact area II, and an electrode III disposed above the dielectric layer II; the N + Contact area II and electrode III are in contact through contact holes on dielectric layer II; the P + Contact area II is in contact with electrode IV; A filter film I is disposed on the sub-detector II; a bonding layer is disposed on the filter film I to connect the sub-detector I and the sub-detector II; through holes are disposed on the electrodes II and III to interconnect with the peripheral circuit.

2. The PIN-type stacked laser detector resistant to strong light according to claim 1, characterized in that, The detector is encapsulated in a tube, with an optical window on top of the tube, and a filter film II is installed on top of the optical window; during encapsulation, electrode II and electrode III are short-circuited.

3. The PIN-type stacked laser detector resistant to strong light according to claim 1, characterized in that, The thickness of sub-detector I is less than the thickness of sub-detector II.

4. The PIN-type stacked laser detector resistant to strong light according to claim 1, characterized in that, The bonding layer is able to transmit incident light.

5. The PIN-type stacked laser detector resistant to strong light according to claim 1, characterized in that, The filter film II is a bandpass filter film, and the starting wavelength of its passband width is determined by the signal light wavelength, while the cutoff wavelength is determined by the detector design.

6. The PIN-type stacked laser detector resistant to strong light according to claim 5, characterized in that, When the photocurrents generated by sunlight in sub-detector I and sub-detector II are equal, the sunlight current can be eliminated; at the same time, filter film I is used to prevent signal light from entering sub-detector II, so as to avoid affecting the signal photocurrent when eliminating the sunlight current.

7. The PIN-type stacked laser detector resistant to strong light according to claim 6, characterized in that, The filter film I must have high reflectivity in the λ0-λ1 to λ0+λ1 band and low reflectivity in the band after λ0+λ1; λ0±λ1 is the wavelength range of the signal light. The filter film II needs to meet the requirement of λ0-λ1 to λ n Low reflectivity in one band, high reflectivity in other bands; where λ n The value of satisfies that the incident light wavelength range is from λ0-λ1 to λ n At that time, the photocurrents of sub-detector I and sub-detector II are consistent.

8. The PIN-type stacked laser detector resistant to strong light according to any one of claims 1 to 7, characterized in that, The manufacturing process of this detector is as follows: (1) Prepare a clean P-type epitaxial silicon wafer; (2) The P of the sub-detector I is formed by photolithography. + Contact area I pattern, and P formed by high-dose boron injection. + Contact area I; (3) Deposition medium layer I; (4) Etch contact holes in dielectric layer I; (5) Electrode II is formed by depositing metallic aluminum on the front side and then sequentially through photolithography and etching; (6) Flip the epitaxial silicon wafer so that the front side is down and the back side is up, in preparation for bonding; (7) Prepare a clean P-type monocrystalline silicon wafer; (8) The N-type sub-detector II is formed by photolithography. + Contact area II pattern, and N formed by injecting a large dose of phosphorus. + Contact area II; (9) Deposition medium layer II; (10) Etch contact holes in dielectric layer II; (11) Metallic aluminum is deposited on the front side, and electrode III is formed by photolithography and etching; (12) Filter film I is deposited on the front side; (13) The front side of the epitaxial silicon wafer containing sub-detector I is bonded to the front side of the single-crystal silicon wafer containing sub-detector II through a bonding layer; (14) The low resistivity substrate of the epitaxial silicon wafer is removed by mechanical polishing and self-stopping etching in sequence; (15) The N-type sub-detector I is formed by photolithography. + Contact area I pattern, and N is formed by injecting a large dose of phosphorus. + Contact area I; (16) Deposition of antireflective membrane; (17) Etch contact holes in the antireflection film; (18) Deposit metallic aluminum and form electrode I by photolithography and etching in sequence; (19) Thinning of single-crystal silicon wafers is achieved by first mechanically grinding and then polishing; (20) The P of the sub-detector II was formed by injecting a large dose of boron. + Contact area II; (21) Deposit metallic aluminum to form electrode IV; (22) Through holes corresponding to electrode II and electrode III are formed sequentially by photolithography and deep silicon etching.

9. The PIN-type stacked laser detector resistant to strong light according to claim 8, characterized in that, When manufacturing this detector for the first time, it needs to be calibrated using filter II on the optical window of the tube shell. The procedure is as follows: (1) The detector is encapsulated in a tube shell, but the light window is not sealed; (2) Using a simulated solar light source, the output current of the two sub-detectors at different wavelengths was tested respectively; (3) Starting from wavelength λ0-λ1, measure and record the output current values ​​of the two sub-detectors every 10nm; (4) The output current values ​​of sub-detector I and sub-detector II at different wavelengths are summed up respectively. Since the longer the wavelength, the larger the photocurrent of sub-detector II is relative to sub-detector I, there must be a wavelength λ n This ensures that the accumulated currents of the two sub-detectors are consistent. (5) A filter film II is deposited on the optical window, characterized in that it can only transmit wavelengths from λ0-λ1 to λ n The light; (6) Seal the light window with filter film II onto the tube shell.

Images