A middle wave infrared detection chip and system

Abstract

The application provides a middle wave infrared detection chip and system, the chip is composed of multiple detection units arranged in the same plane, the detection units are sequentially composed of a substrate, a buffer layer, a lower contact layer, an absorption layer, a barrier layer and an upper contact layer, the chip is arranged based on an nBp type structure, the buffer layer, the lower contact layer, the absorption layer, the barrier layer and the upper contact layer all adopt a superlattice structure arranged in multiple periods, the thickness, the number of layers and the doping concentration of the multiple layers of InAs doped layers and GaSb doped layers arranged in each period are controlled, so that the suppression of dark current in the middle infrared detection process is realized, and the quantum efficiency is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of infrared detection technology, and in particular to a mid-wave infrared detection chip and system. BACKGROUND

[0002] Mid-wave infrared detector (MWIR) is an important branch of infrared detection technology, which is usually used to detect infrared radiation in the wavelength range of 3~5μm. Such detectors have wide applications in both military and civilian fields, such as reconnaissance, target identification, missile guidance and night vision equipment in the military field. Due to its good imaging capability and high sensitivity, the mid-wave infrared detector can provide clear target images in various complex environments. In the industrial and civilian fields, it can be used for environmental monitoring, gas detection, temperature imaging and medical imaging, etc. Especially in gas detection, many industrial gases have characteristic absorption in the mid-infrared band, so the mid-wave infrared detector can effectively identify and monitor these gases. In addition, in the field of scientific research, the mid-wave infrared detector is also used to observe the thermal radiation of celestial bodies and the earth's surface in astronomy and remote sensing technology.

[0003] In the infrared focal plane detection system, the dark current level and quantum efficiency are important parameters to measure the performance of the device. In the superlattice infrared detector, the main dark current mechanisms include diffusion current, generation recombination current, direct tunneling current and trap assisted tunneling current. Finding appropriate absorption layer structure materials and adjusting appropriate parameters can effectively reduce the dark current level of the device, improve the quantum efficiency, and further improve the performance of the detector.

[0004] In the prior art, the second type of superlattice infrared detector is an important branch of current infrared detection technology, and its application background mainly comes from the demand for high-performance infrared detection equipment. The overall structure is pπMp structure, which includes a lower electrode, an InAs / GaSb superlattice contact layer and an absorption layer, an InAs / GaSb / AlSb / GaSb superlattice barrier layer, an InAs / GaSb superlattice contact layer and an upper electrode, which are sequentially distributed. The contact layer, the absorption layer and the barrier layer are all p-type regions. However, the second type of superlattice material is still in the initial development stage, and the existing technical means is not very mature, and the problem of high dark current and low quantum efficiency of the second type of superlattice material has not been solved. SUMMARY

[0005] In view of this, the embodiments of the present application provide a mid-wave infrared detection chip and system to eliminate or improve one or more defects in the prior art, and overcome the problem of high dark current and low quantum efficiency of the existing mid-wave infrared detector.

[0006] One aspect of the present application provides a mid-wave infrared detection chip, the mid-wave infrared detection chip is composed of a plurality of detection units arranged in the same plane, the detection unit comprises: a substrate, a buffer layer, a lower contact layer, an absorption layer, a barrier layer and an upper contact layer.

[0007] The buffer layer is grown on the substrate, and is made of gallium-antimony p-type doped material with a doping concentration of 1×10 15 ~1×10 18 cm -3 ;

[0008] The lower contact layer is grown on the buffer layer, and the lower contact layer is a multi-period stacked arrangement, each period comprising a first InAs doped layer and a first GaSb doped layer of a 9ML / 9ML structure arranged continuously; the lower contact layer is p-type doped, and the first InAs doped layer and the first GaSb doped layer have a doping concentration of 1×10 16 ~1×10 18 cm -3 ;

[0009] The absorption layer is grown on the lower contact layer, and the absorption layer is a multi-period stacked arrangement, each period comprising a second InAs doped layer and a second GaSb doped layer of a 9ML / 9ML structure arranged continuously; the absorption layer is p-type doped, and the second InAs doped layer and the second GaSb doped layer have a doping concentration of 1×10 15 ~5×10 16 cm -3 ;

[0010] The barrier layer is grown on the absorption layer, and the barrier layer is a multi-period stacked arrangement, each period comprising a third InAs doped layer and a third GaSb doped layer of a 12ML / 7ML structure arranged continuously; the barrier layer is n-type doped, and the third InAs doped layer and the third GaSb doped layer have a doping concentration of 1×10 15 ~1×10 18 cm -3 ;

[0011] The upper contact layer is grown on the barrier layer, and the barrier layer is a multi-period stacked arrangement, each period comprising a fourth InAs doped layer and a fourth GaSb doped layer of a 5ML / 4ML structure arranged continuously; the upper contact layer is n-type doped, and the fourth InAs doped layer and the fourth GaSb doped layer have a doping concentration of 1×10 16 ~1×10 18 cm -3 .

[0012] In some embodiments, the substrate is a GaSb substrate with a thickness of 0.5~1μm, and the thickness of the buffer layer is 100~500nm.

[0013] In some embodiments, the doping concentration of the first InAs doped layer and the first GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 The doping concentration of the second InAs doped layer and the second GaSb doped layer is 1×10⁻⁶. 15 cm -3 The doping concentration of the third InAs doped layer and the third GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 The upper contact layer is n-type doped, and the doping concentration of the fourth InAs doped layer and the fourth GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 .

[0014] In some embodiments, the thickness of the buffer layer is 500 nm, the thickness of the lower contact layer is 1500 nm, the thickness of the absorption layer is 5500 nm, the thickness of the barrier layer is 250 nm, and the thickness of the upper contact layer is 200 nm.

[0015] In some embodiments, the buffer layer doping concentration is 1×10⁻⁶. 18 cm -3 .

[0016] On the other hand, the present invention also provides a mid-wave infrared detection system, the system comprising:

[0017] As mentioned above, the mid-wave infrared detection chip, readout circuit, preamplifier, analog-to-digital converter, digital signal processor, and data output interface are included.

[0018] The readout circuit is used to acquire and filter the electrical signals generated by the mid-wave infrared detection chip.

[0019] The preamplifier is used to amplify the analog signal output by the readout circuit.

[0020] An analog-to-digital converter is used to convert the amplified analog signal output by the preamplifier into a digital signal.

[0021] The digital signal processor performs filtering, signal enhancement, data compression, and / or image generation on the digital signal output by the analog-to-digital converter.

[0022] The data output interface is used to output the data obtained after processing by the digital signal processor.

[0023] In some embodiments, the system further includes an optical lens for focusing and transmitting the infrared beam to be detected to the mid-wave infrared detection chip for photosensitive sensing.

[0024] In some embodiments, the system further includes a temperature control device, the temperature control device comprising:

[0025] A thermistor sensor is used to detect the temperature of the mid-wave infrared detection chip;

[0026] A Dewar refrigeration device is used to cool and dissipate heat from the mid-wave infrared detection chip; a temperature control unit is connected to the thermistor sensor and the Dewar refrigeration device to detect and control the temperature of the mid-wave infrared detection chip.

[0027] In some embodiments, the system further includes a display device for displaying data or images obtained after processing by the digital signal processor.

[0028] The beneficial effects of the present invention are at least as follows:

[0029] The mid-wave infrared detection chip and system of the present invention comprises multiple detection units arranged in the same plane. Each detection unit consists of a substrate, a buffer layer, a lower contact layer, an absorption layer, a barrier layer, and an upper contact layer. The chip is based on an nBp-type structure. The buffer layer, lower contact layer, absorption layer, barrier layer, and upper contact layer all adopt a superlattice structure with multi-period stacked arrangement. By controlling the thickness, number of layers, and doping concentration of multiple InAs doped layers and GaSb doped layers stacked in each period, dark current can be suppressed during mid-infrared detection, and quantum efficiency can be effectively improved.

[0030] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows, and will also become apparent in part to those skilled in the art upon studying the description, or may be learned by practice of the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures specifically pointed out in the description and drawings.

[0031] Those skilled in the art will understand that the objectives and advantages achievable with the present invention are not limited to those specifically described above, and that the above and other objectives achievable with the present invention will become clearer from the following detailed description. Attached Figure Description

[0032] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, are not intended to limit the invention. In the drawings:

[0033] Figure 1This is a structural diagram of a single detection unit in a mid-wave infrared detection chip according to an embodiment of the present invention.

[0034] Figure 2 This is a band structure diagram of the nBp structure used in the mid-wave infrared detection chip described in another embodiment of the present invention.

[0035] Figure 3 (a) shows the relationship between quantum efficiency and wavelength at 77K. Figure 3 Figure (b) shows the relationship between dark current density and bias voltage at 77K.

[0036] Figure 4 This is a schematic diagram of the structure of a mid-wave infrared detection system according to an embodiment of the present invention.

[0037] Figure 5 This is a schematic diagram of the structure of a mid-wave infrared detection system according to another embodiment of the present invention. Reference numerals:

[0038] 110: Mid-wave infrared detection chip; 111: Upper contact layer; 112: Barrier layer;

[0039] 113: Absorbing layer; 114: Lower contact layer; 115: Buffer layer;

[0040] 116: Substrate; 120: Readout circuit; 130: Preamplifier;

[0041] 140: Analog-to-digital converter; 150: Digital signal processor; 160: Data output interface;

[0042] 210: Optical lens; 310: Temperature control device; 311: Thermistor sensor;

[0043] 312: Thermoelectric cooler; 313: Heat sink; 314: Temperature control unit. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0045] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0046] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, element, step, or component, but does not exclude the presence or addition of one or more other features, elements, steps, or components.

[0047] It should also be noted that, unless otherwise specified, the term "connection" in this article can refer not only to a direct connection, but also to an indirect connection involving an intermediary.

[0048] In the following description, embodiments of the invention will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar parts, or the same or similar steps.

[0049] The mid-wave infrared detector chip in this application adopts an nBp-type structure with a flexible and adjustable design. By precisely controlling the thickness and doping level of the absorption region, it optimizes results such as dark current and quantum efficiency, thereby improving the overall performance of the photoelectric conversion device. Specifically, this structure can cleverly construct a highly efficient electron barrier by adjusting the parameters of each region. This barrier is formed by a wide-bandgap blocking layer, which not only provides a significant valence band shift to ensure effective hole blocking, but also maintains a small conduction band shift to support smooth electron transport. By optimizing the doping concentration, the mobility and lifetime of photogenerated electrons (as minority carriers) can be significantly increased, thereby improving the efficiency of these electrons being collected. This process not only reduces unnecessary diffusion current, but also significantly improves the quantum efficiency of the device, i.e., the proportion of incident photons converted into usable electrical signals.

[0050] Specifically, such as Figure 1 As shown, the present invention provides a mid-wave infrared detection chip 110, which is composed of multiple detection units arranged in the same plane. The detection unit includes: a substrate 116, a buffer layer 115, a lower contact layer 114, an absorption layer 113, a barrier layer 112, and an upper contact layer 111.

[0051] In some embodiments, the substrate 116 is a GaSb substrate 116 with a thickness of 0.5~1μm, and the thickness of the buffer layer 115 is 100~500nm.

[0052] Buffer layer 115 is grown and disposed on substrate 116, using GaSb-based p-type doped material with a doping concentration of 1×10⁻⁶. 15 ~1×10 18 cm -3 ;

[0053] The lower contact layer 114 is grown on the buffer layer 115. The lower contact layer 114 is arranged in a multi-period stack, and each period contains a first InAs doped layer and a first GaSb doped layer with a continuously arranged 9ML / 9ML structure. The lower contact layer 114 is p-type doped, and the doping concentration of the first InAs doped layer and the first GaSb doped layer is 1×10⁻⁶. 16 ~1×10 18 cm -3 ML indicates a thickness of 0.3 nm, and the 9ML / 9ML structure indicates a first InAs doped layer with a thickness of 9 × 0.3 nm and a first GaSb doped layer with a thickness of 9 × 0.3 nm.

[0054] The absorber layer 113 is grown on the lower contact layer 114. The absorber layer 113 is arranged in a multi-period stack, and each period contains a second InAs doped layer and a second GaSb doped layer with a continuously arranged 9ML / 9ML structure. The absorber layer 113 is p-type doped, and the doping concentration of the second InAs doped layer and the second GaSb doped layer is 1×10⁻⁶. 15 ~1×10 16 cm -3 ML indicates a thickness of 0.3 nm. The 9ML / 9ML structure indicates a second InAs doped layer with a thickness of 9 × 0.3 nm and a second GaSb doped layer with a thickness of 9 × 0.3 nm.

[0055] Barrier layer 112 is grown on absorber layer 113. Barrier layer 112 is arranged in a multi-period stack, with each period containing a continuously arranged 12ML / 7ML third InAs doped layer and third GaSb doped layer. Barrier layer 112 is n-type doped, and the doping concentration of the third InAs doped layer and third GaSb doped layer is 1×10⁻⁶. 15 ~1×10 18 cm -3 ML indicates a thickness of 0.3 nm. The 12ML / 7ML structure represents a third InAs doped layer with a thickness of 12 × 0.3 nm and a third GaSb doped layer with a thickness of 7 × 0.3 nm.

[0056] The upper contact layer 111 is grown on the barrier layer 112, which is a multi-period stacked arrangement. Each period contains a fourth InAs doped layer and a fourth GaSb doped layer with a continuously arranged 5ML / 4ML structure. The upper contact layer 111 is n-type doped, and the doping concentration of the fourth InAs doped layer and the fourth GaSb doped layer is 1×10⁻⁶. 16 ~1×10 18 cm -3 ML indicates a thickness of 0.3 nm. The 5ML / 4ML structure indicates a fourth InAs doped layer with a thickness of 5 × 0.3 nm and a fourth GaSb doped layer with a thickness of 4 × 0.3 nm.

[0057] In some embodiments, the doping concentration of the first InAs doped layer and the first GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 The doping concentration of the second InAs doped layer and the second GaSb doped layer is 1×10⁻⁶. 15 cm -3 The doping concentration of the third InAs doped layer and the third GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 The upper contact layer 111 is n-type doped, and the doping concentration of the fourth InAs doped layer and the fourth GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 .

[0058] In some embodiments, the thickness of the buffer layer 115 is 500 nm, the thickness of the lower contact layer 114 is 1500 nm, the thickness of the absorption layer 113 is 5500 nm, the thickness of the barrier layer 112 is 250 nm, and the thickness of the upper contact layer 111 is 200 nm.

[0059] In some embodiments, the buffer layer doping concentration is 1×10⁻⁶. 18 cm -3 .

[0060] In this embodiment, an nBp-type structure is employed, which creates a high electronic barrier, allowing the wide-bandgap barrier layer to provide a large valence band shift and a minimal conduction band shift, thereby further reducing dark current. Based on this, the absorption layer parameters of the structure are optimized, effectively improving the overall performance of the device.

[0061] The relationship between the capacitor and voltage can be obtained from the following formula. Adjusting the electron concentration can deepen the electron potential well, thereby further reducing the generation of dark current.

[0062] ;

[0063] Where C represents the unit heterojunction capacitance, q is the electron charge, T represents the temperature, ξ1 represents the dielectric constant of the narrowband material, ξ2 represents the dielectric constant of the wideband material, and N... A1 Represents the impurity concentration in the narrow-band P-region, N D2 θ represents the donor impurity concentration in the broadband N-region (narrowband material parameters are all marked 1, and broadband material parameters are all marked 2), and θ represents the ratio of minority carriers to majority carriers at the interface.

[0064] ;

[0065] Among them, V D1 With V D2 These represent the heights of the barriers on both sides.

[0066] Qualitative analysis of the following formula shows that the higher the doping concentration, the smaller the dark current. However, when the doping concentration is too high, the electric field will also increase, which will increase the value of the tunneling current to some extent.

[0067] ;

[0068] Among them, J SRH Let n be the recombination current density, q be the electron charge, and n be the total charge. i Intrinsic carrier concentration, and denoted as electron lifetime and hole lifetime, respectively, and n and p as electron and hole concentration, respectively.

[0069] Regarding quantum efficiency The relevant formulas are shown below:

[0070] ;

[0071] in, Let L be the absorption coefficient of the material, L be the thickness of the absorption layer, R be the surface reflectivity, and d be the depth of the incident light into the absorption layer. From the above formula, it can be qualitatively concluded that, under the same conditions, the greater the thickness of the absorption region, the higher the quantum efficiency.

[0072] Based on the relationships given in the above formulas, one embodiment of the present invention provides and optimizes a novel nBp device structure. For the absorption layer, the material ratio of InAs and GaSb is controlled, and the thickness and doping concentration of the absorption layer are strictly selected to achieve higher performance. Simultaneously, p-type doping is used in the absorption region to ensure minority carrier type, while n-type doping is used in the barrier layer and the top absorption layer, and p-type doping is used in the bottom absorption layer, forming an overall nBp structure, thus comprehensively ensuring optimal overall device performance.

[0073] This embodiment proposes an nBp structure for mid-wave (3-5 μm) infrared detection and optimizes parameters such as doping and thickness of each layer. The device structure uses an InAs / GaSb superlattice as the contact layer, absorption layer, and barrier layer. The absorption layer is weakly doped with a doping concentration of 1 × 10⁻⁶. 15 cm -3 (The typical doping concentration range is 10) 15 ~0 16 cm -3 The contact layer is heavily doped, with a doping concentration of 5 × 10⁻⁶. 17 cm -3 (The typical doping concentration range is 10) 16 ~10 18 cm -3 The barrier layer is located between the absorber layer and the contact layer, and its doping concentration is 5 × 10⁻⁶. 15cm -3 (The typical doping concentration range is 10) 15 ~10 18 cm -3 This embodiment focuses on screening and optimizing the absorber layer material to ensure that the device has high quantum efficiency.

[0074] Specifically, a mid-to-long-wave infrared detector is provided, comprising, from top to bottom:

[0075] Contact layer on 111-InAs / GaSb superlattice.

[0076] 112-InAs / GaSb superlattice barrier layer.

[0077] 113-InAs / GaSb superlattice absorption layer.

[0078] 114-InAs / GaSb superlattice under-contact layer.

[0079] 115-GaSb buffer layer.

[0080] 116-GaSb substrate.

[0081] Specifically, a 500 nm GaSb buffer layer 115, p-type doped, is grown on a GaSb substrate 116 with a doping concentration of 1 × 10⁻⁶. 18 cm -3 A 1500 nm superlattice structure was grown on buffer layer 115 as the bottom contact layer, p-type doped with a doping concentration of 5 × 10⁻⁶. 17 cm -3 The superlattice structure is 9ML InAs / 9ML GaSb; a 5500nm superlattice structure is grown on the lower contact layer 114 as the absorption layer 113, which is p-type doped with a doping concentration of 1×10⁻⁶. 15 cm -3 The superlattice structure is 9 mL InAs / 9 mL GaSb; a 250 nm superlattice structure is grown on the absorber layer 113 as the barrier layer 112, which is n-type doped with a doping concentration of 5 × 10⁻⁶. 15 cm -3 The superlattice structure is 12 mL InAs / 7 mL GaSb; a 200 nm superlattice structure is grown on the barrier layer 112 as the upper contact layer 111, which is n-type doped with a doping concentration of 5 × 10⁻⁶. 17 cm -3The superlattice structure is 5ML InAs / 4ML GaSb; the electrodes can be mounted between the lower contact layer 114 and the buffer layer 115, and above the upper contact layer 111. Here, ML represents a thickness unit, each ML being 0.3nm. For example, "9ML InAs / 9ML GaSb" means that a 9×0.3nm thick InAs doped layer and a 9×0.3nm thick GaSb doped layer constitute one cycle, and multiple cycles are stacked.

[0082] Figure 2 The diagram shows the energy band structure of this nBp device. It is clear that a significant hole barrier is formed in the valence band within the barrier region, effectively separating the upper contact layer 111 from the absorption layer 113. Therefore, it prevents most holes injected from the upper contact layer 111 from entering the absorption layer 113, thus avoiding potential interference from these holes to the photoexcitation process of the absorption layer 113. Simultaneously, a barrier also exists in the conduction band, due to the absorption and barrier regions using the same doping type but different doping concentrations. This difference in doping concentration directly affects the height of the conduction band barrier. Since the absorption layer 113 and the upper contact layer 111 use the same superlattice material, the presence of this conduction band barrier significantly hinders the process under low bias conditions, resulting in a very low dark current density.

[0083] At lower bias voltages, while the dark current properties are excellent, photogenerated carriers struggle to overcome the potential barrier and be collected by the electrodes. Normal collection of photogenerated carriers only occurs when the turn-on voltage is reached, which is limited by the height of the conduction band barrier. Therefore, the conduction band barrier height of the barrier layer 112 material was precisely designed to be approximately 0.2 eV, enabling efficient collection of photogenerated carriers at a bias voltage of -0.2 V, significantly reducing device fabrication requirements.

[0084] like Figure 3 As shown, under 77 K conditions, with a bias voltage of -0.2 V applied to the lower contact layer 114 of the device, the dark current density of this structure before optimization is 10. -4 -10 -5 A / cm 2 The peak quantum efficiency is below 35%; after optimization, when a -0.2 V bias is applied to the lower contact layer 114 of the device at a temperature of 77 K, the dark current density is significantly reduced to below 10. -6 A / cm 2 Meanwhile, the peak quantum efficiency is greater than 45%, achieving dual optimization of low dark current and high quantum efficiency, which significantly improves the overall performance of the device.

[0085] On the other hand, the present invention also provides a mid-wave infrared detection system, the system comprising:

[0086] The aforementioned mid-wave infrared detection chip 110, readout circuit 120, preamplifier 130, analog-to-digital converter 140, digital signal processor 150, and data output interface 160 are included.

[0087] The readout circuit 120 is used to acquire and filter the electrical signals generated by the mid-wave infrared detection chip 110.

[0088] The preamplifier 130 is used to amplify the analog signal output by the readout circuit 120.

[0089] The analog-to-digital converter 140 is used to convert the amplified analog signal output by the preamplifier 130 into a digital signal.

[0090] The digital signal processor 150 performs filtering, signal enhancement, data compression, and / or image generation on the digital signal output by the analog-to-digital converter 140.

[0091] The data output interface 160 is used to output the data obtained after processing by the digital signal processor 150.

[0092] In some embodiments, the system further includes an optical lens 210 for focusing and transmitting the infrared beam to be detected to the mid-wave infrared detection chip 110 for photosensitive sensing.

[0093] In some embodiments, the system further includes a temperature control device 310, the temperature control device 310 comprising:

[0094] Thermistor sensor 311 is used to detect the temperature of mid-wave infrared detection chip 110;

[0095] The Dewar cooling device 312 is used to cool and dissipate heat from the mid-wave infrared detection chip 110;

[0096] Temperature control unit 313 is connected to thermistor sensor 311 and Dewar refrigeration device 312 to detect and control the temperature of mid-wave infrared detection chip 110.

[0097] In some embodiments, the system further includes a display device for displaying data or images obtained after processing by the digital signal processor 150.

[0098] In summary, the mid-wave infrared detection chip and system of the present invention comprises multiple detection units arranged in the same plane. Each detection unit consists of a substrate, a buffer layer, a lower contact layer, an absorption layer, a barrier layer, and an upper contact layer. The chip is based on an nBp-type structure, and the buffer layer, lower contact layer, absorption layer, barrier layer, and upper contact layer all adopt a superlattice structure with multi-period stacked arrangement. By controlling the thickness, number of layers, and doping concentration of multiple InAs doped layers and GaSb doped layers stacked in each period, dark current can be suppressed during mid-infrared detection, and quantum efficiency can be effectively improved.

[0099] Those skilled in the art will understand that the exemplary components, systems, and methods described in conjunction with the embodiments disclosed herein can be implemented in hardware, software, or a combination of both. Whether implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention. When implemented in hardware, it can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this invention are programs or code segments used to perform the desired tasks. The programs or code segments can be stored in a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried in a carrier wave.

[0100] It should be clarified that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of the present invention.

[0101] In this invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or in place of features of other embodiments.

[0102] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A mid-wave infrared detection chip, characterized in that, The mid-wave infrared detection chip consists of multiple detection units arranged in the same plane, and the detection unit includes: Substrate; A buffer layer, grown on the substrate, is made of gallium-antimony p-type doped material with a doping concentration of 1×10⁻⁶. 15 ~1×10 18 cm -3 ; A lower contact layer is grown on the buffer layer. The lower contact layer is arranged in a multi-period stack, with each period containing a first InAs doped layer and a first GaSb doped layer of continuously arranged 9ML / 9ML structures. The lower contact layer is p-type doped, and the doping concentration of the first InAs doped layer and the first GaSb doped layer is 1×10⁻⁶. 16 ~1×10 18 cm -3 ; An absorption layer is grown on the lower contact layer. The absorption layer is arranged in a multi-period stacked configuration, with each period containing a continuously arranged 9ML / 9ML structured second InAs doped layer and second GaSb doped layer. The absorption layer is p-type doped, and the doping concentration of the second InAs doped layer and the second GaSb doped layer is 1×10⁻⁶. 15 ~5×10 16 cm -3 ; A barrier layer is grown on the absorber layer. The barrier layer is arranged in a multi-period stacked configuration, with each period containing a continuously arranged 12ML / 7ML third InAs doped layer and a third GaSb doped layer. The barrier layer is n-type doped, and the doping concentration of the third InAs doped layer and the third GaSb doped layer is 1×10⁻⁶. 15 ~1×10 18 cm -3 ; An upper contact layer is grown on the barrier layer. The barrier layer is arranged in a multi-period stacked configuration, with each period containing a fourth InAs doped layer and a fourth GaSb doped layer in a continuously arranged 5ML / 4ML structure. The upper contact layer is n-type doped, and the doping concentration of the fourth InAs doped layer and the fourth GaSb doped layer is 1×10⁻⁶. 16 ~1×10 18 cm -3 .

2. The mid-wave infrared detection chip according to claim 1, characterized in that, The substrate has a thickness of 0.5~1μm, and the buffer layer has a thickness of 100~500nm.

3. The mid-wave infrared detection chip according to claim 2, characterized in that, The doping concentration of the first InAs doped layer and the first GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 The doping concentration of the second InAs doped layer and the second GaSb doped layer is 1×10⁻⁶. 15 cm -3 The doping concentration of the third InAs doped layer and the third GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 The upper contact layer is n-type doped, and the doping concentration of the fourth InAs doped layer and the fourth GaSb doped layer is 5 × 10⁻⁶. 17 cm -3 .

4. The mid-wave infrared detection chip according to claim 3, characterized in that, The thickness of the buffer layer is 500 nm, the thickness of the lower contact layer is 1500 nm, the thickness of the absorption layer is 5500 nm, the thickness of the barrier layer is 250 nm, and the thickness of the upper contact layer is 200 nm.

5. The mid-wave infrared detection chip according to claim 4, characterized in that, The buffer layer has a doping concentration of 1×10⁻⁶. 18 cm -3 .

6. The mid-wave infrared detection chip according to claim 5, characterized in that, The substrate is made of GaSb material.

7. A mid-wave infrared detection system, characterized in that, The system includes: The mid-wave infrared detection chip as described in any one of claims 1 to 6; The readout circuit is used to acquire and filter the electrical signals generated by the mid-wave infrared detection chip; A preamplifier is used to amplify the analog signal output by the readout circuit; An analog-to-digital converter is used to convert the amplified analog signal output from the preamplifier into a digital signal. A digital signal processor performs filtering, signal enhancement, data compression, and / or image generation on the digital signal output by the analog-to-digital converter; The data output interface is used to output the data obtained after processing by the digital signal processor.

8. The mid-wave infrared detection system according to claim 7, characterized in that, The system also includes: An optical lens is used to focus the infrared beam to be detected and transmit it to the mid-wave infrared detection chip for photosensitive sensing.

9. The mid-wave infrared detection system according to claim 7, characterized in that, The system also includes a temperature control device, which comprises: A thermistor sensor is used to detect the temperature of the mid-wave infrared detection chip; A Dewar refrigeration device is used to cool and dissipate heat from the mid-wave infrared detection chip; The temperature control unit is connected to the thermistor sensor and the Dewar refrigeration device to detect and control the temperature of the mid-wave infrared detection chip.

10. The mid-wave infrared detection system according to claim 7, characterized in that, The system also includes: A display device for displaying data or images obtained after processing by the digital signal processor.

Images