Long-wave infrared detector based on electric field intensity distribution regulation and control and preparation method thereof

Abstract

The invention discloses a long-wave infrared detector based on electric field intensity distribution regulation and control and a preparation method, and relates to the technical field of semiconductors, the long-wave infrared detector comprises a substrate, a bottom contact layer, a hole barrier layer, an absorption layer, an electron barrier layer and a top contact layer which are sequentially arranged from bottom to top; wherein the bottom contact layer and the hole barrier layer adopt an InAs / GaSb / AlSb / GaSb superlattice structure; the absorption layer, the electron barrier layer and the top contact adopt an InAs / GaSb superlattice structure; the doping concentration of the absorption layer is greater than the doping concentration of the hole barrier layer and the electron barrier layer. The doping concentration of the absorption layer is set to be greater than that of the barrier layer, so that the width of a depletion region of the absorption layer is reduced, the depletion region deviates towards the barrier layer, the probability of SRH recombination is reduced, G-R current can be effectively inhibited, and the overall dark current level is reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more specifically, to a long-wave infrared detector based on electric field intensity distribution modulation and its fabrication method. Background Technology

[0002] Long-wave infrared (LWIR) detectors can be used in remote sensing, thermal imaging, pollutant detection, and spectroscopy.

[0003] The band structure of type-II superlattices can modulate spectral absorption by utilizing large-band shifts and inverse strain between material layers, suppressing Auger recombination and thus effectively reducing dark current levels. Furthermore, InAs / GaSb type-II superlattices offer advantages such as good lattice matching and higher uniformity over large areas. When designing device structures, potential barriers are typically introduced to further reduce dark current levels. Related research shows that the introduction of barrier structures has almost no impact on the optical performance of the device, while suppressing dark currents generated by majority carrier flow to reduce diffusion dark currents and suppressing dark currents associated with the Shockley-Read-Hall process in the depletion region. Optimizing the doping and thickness of each layer of the device can effectively reduce dark current levels and improve detector performance. Summary of the Invention

[0004] This invention provides a long-wave infrared detector based on electric field intensity distribution modulation and its fabrication method, in order to overcome at least one technical problem existing in the prior art.

[0005] On one hand, embodiments of the present invention provide a long-wave infrared detector based on electric field intensity distribution modulation, comprising: a substrate, a bottom contact layer, a hole barrier layer, an absorption layer, an electron barrier layer, and a top contact layer arranged sequentially from bottom to top; wherein, The bottom contact layer and the hole barrier layer adopt an InAs / GaSb / AlSb / GaSb superlattice structure; the absorption layer, the electron barrier layer and the top contact adopt an InAs / GaSb superlattice structure. The doping concentration of the absorption layer is greater than that of the hole barrier layer and the electron barrier layer.

[0006] Optionally, the bottom contact layer is a superlattice structure of 18ML InAs / 3ML GaSb / 5ML AlSb / 3ML GaSb, with a layer thickness of less than 1μm, n-type doped, and a doping concentration of 1×10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 .

[0007] Optionally, the hole barrier layer is a superlattice structure of 18ML InAs / 1ML GaSb / 5ML AlSb / 1ML GaSb, with a layer thickness of less than 1μm, n-type doped, and a doping concentration of 1×10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 .

[0008] Optionally, the absorber layer is a 15MLInAs / 6MLGaSb superlattice structure with a thickness of 2μm to 6μm, p-type doped, and a doping concentration of 1×10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 .

[0009] Optionally, the electronic barrier layer is an 8 mL InAs / 10 ​​mL GaSb superlattice structure with a thickness of less than 1 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 .

[0010] Optionally, the top contact layer is a 15ML InAs / 6ML GaSb superlattice structure with a thickness of less than 1μm, p-type doped, and a doping concentration of 1×10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 .

[0011] Optionally, the layer thickness ratio of InAs to GaSb in the InAs / GaSb superlattice structure of the absorption layer can be adjusted to control the bandgap of the absorption layer within the range of 0.088eV to 0.155eV.

[0012] Optionally, a buffer layer is also included, the buffer layer being located between the substrate and the bottom contact layer.

[0013] On the other hand, the present invention also provides a method for fabricating a detector, which is carried out in a vacuum cavity using a molecular epitaxial growth process.

[0014] Optionally, it includes: A buffer layer is grown on the substrate; A bottom contact layer is grown on the buffer layer; A hole barrier layer is grown on the bottom contact layer; An absorption layer is grown on the hole barrier layer; An electron barrier layer is grown on the absorption layer; A top contact layer is grown on the electron barrier layer.

[0015] The innovative aspects of this invention include: In this embodiment, the doping concentration of the absorption layer is set to be greater than that of the barrier layer. This allows the depletion region to shift towards the barrier layer, causing the electric field drop to fall more on the barrier layer. Since the barrier layer has a large band gap, the probability of SRH recombination decreases after the width of the depletion region of the absorption layer is reduced and the depletion region shifts towards the barrier layer. This can effectively suppress the GR current and reduce the overall dark current level, which is one of the innovative points of this embodiment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a detector provided in an embodiment of the present invention; Figure 2 The dark current characteristic curves are shown for two cases: when the doping concentration of the absorption layer is greater than that of the barrier layer and when the doping concentration of the absorption layer is less than that of the barrier layer. Figure 3 The electric field intensity distribution is shown for two cases: when the doping concentration of the absorption layer is greater than that of the barrier layer and when the doping concentration of the absorption layer is less than that of the barrier layer. Figure 4 This is a flowchart of a preparation method provided in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be noted that the terms "comprising" and "having," and any variations thereof, in the embodiments and drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0020] This invention discloses a long-wave infrared detector based on electric field intensity distribution modulation and its fabrication method. These will be described in detail below.

[0021] Figure 1 This is a schematic diagram of a detector provided in an embodiment of the present invention. Please refer to it. Figure 1 The long-wave infrared detector based on electric field intensity distribution modulation provided in this embodiment of the invention includes: The substrate 7, bottom contact layer 5, hole barrier layer 4, absorption layer 3, electron barrier layer 2, and top contact layer 1 are arranged sequentially from bottom to top; wherein, The bottom contact layer 5 and the hole barrier layer 4 adopt an InAs / GaSb / AlSb / GaSb superlattice structure; the absorption layer 3, the electron barrier layer 2 and the top contact layer 1 adopt an InAs / GaSb superlattice structure. The doping concentration of the absorption layer 3 is greater than that of the hole barrier layer 4 and the electron barrier layer 2.

[0022] For details, please refer to Figure 1 The long-wave infrared detector based on electric field intensity distribution modulation includes, from bottom to top, a substrate 7, a bottom contact layer 5, a hole barrier layer 4, an absorption layer 3, an electron barrier layer 2, and a top contact layer 1. The superlattice structure effectively reduces dark current, increases operating temperature, and exhibits good material uniformity. Therefore, in this invention, the bottom contact layer 5, hole barrier layer 4, absorption layer 3, electron barrier layer 2, and top contact layer 1 all employ a superlattice structure.

[0023] For example, an InAs / GaSb / AlSb / GaSb superlattice structure is used as the bottom contact layer 5 and the hole barrier layer 4, and an InAs / GaSb superlattice is used as the absorption layer 3, the electron barrier layer 2, and the top contact layer 1. The bottom contact layer 5 is set to be a 18MLInAs / 3MLGaSb / 5MLAlSb / 3MLGaSb superlattice structure with a layer thickness of less than 1 μm, n-type doped, and a doping concentration of 1 × 10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 Hole barrier layer 4 is a superlattice structure of 18 mL InAs / 1 mL GaSb / 5 mL AlSb / 1 mL GaSb with a layer thickness of less than 1 μm, n-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 By setting the bottom contact layer 5 and the hole barrier layer 4 to the same material, not only can good lattice matching between the two be maintained, reducing defects caused by lattice mismatch, but also excellent band continuity between them can be guaranteed.

[0024] Absorber layer 3 is a 15 mL InAs / 6 mL GaSb superlattice structure with a thickness of 2 μm to 6 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 The second electron barrier layer is a superlattice structure of 8 mL InAs / 10 ​​mL GaSb with a thickness of less than 1 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 The top contact layer 1 is a 15 mL InAs / 6 mL GaSb superlattice structure with a thickness of less than 1 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 .

[0025] By setting the absorption layer 3 to a superlattice structure of 15MLInAs / 6MLGaSb, its bandgap can be made to correspond to the long-wave infrared band. However, it should be noted that setting the absorption layer 3 to a superlattice structure of 15MLInAs / 6MLGaSb is only one structural configuration in this embodiment. In this invention, the layer thickness ratio of InAs to GaSb in the InAs / GaSb superlattice structure of the absorption layer 3 is adjustable, that is, the ratio can also be other values. By adjusting the ratio of the two, the bandgap of the absorption layer 3 can be controlled within the range of 0.088eV to 0.155eV, corresponding to the long-wave infrared band.

[0026] In this embodiment, the thickness of the absorption layer 3 is set to 2 μm to 6 μm to ensure that infrared photons are fully absorbed, achieving high quantum efficiency. Simultaneously, the absorption layer 3 is p-type doped with a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 By increasing the doping concentration of the absorber layer to be greater than that of the barrier layer, the width of the depletion region within the absorber layer 3 becomes narrower, causing the depletion region to shift towards the barrier layer. This results in a greater reduction in the electric field falling within the barrier layer. Because the barrier layer has a large band gap, the reduced width of the depletion region in absorber layer 3 and its shift towards the barrier layer decreases the probability of SRH recombination, effectively suppressing the GR (generation-recombination) current and lowering the overall dark current level. SRH recombination refers to the recombination of electron-hole pairs through the trap level.

[0027] Increasing the doping concentration of the absorption layer 3 narrows the depletion layer width. Therefore, this invention sets the doping concentration of the absorption layer 3 to be greater than that of the barrier layers (hole barrier layer 4 and electron barrier layer 2). This allows the depletion region to shift towards the barrier layer, resulting in a greater electric field drop occurring on the barrier layer. Because the barrier layer has a large band gap, the reduced depletion region width and shift of the depletion region towards the barrier layer decreases the probability of SRH recombination, effectively suppressing GR current and thus reducing the overall dark current level.

[0028] In addition, in order to obtain a flat surface to facilitate the growth of other upper layers, the present invention also provides a buffer layer 6 between the substrate 7 and the bottom contact layer 5, which terminates any defects or damage that may exist on the surface of the substrate 7.

[0029] To visually observe the effect of the doping concentration of the absorption layer 3 on the dark current, simulations were performed in this invention. For example... Figure 2 The figure shows the dark current characteristic curves for two cases: when the doping concentration of the absorbing layer 3 is greater than that of the barrier layer, and when the doping concentration of the absorbing layer 3 is less than that of the barrier layer. The horizontal axis represents the bias voltage (V), and the vertical axis represents the current density (A / cm²). 2 ); Figure 3 The diagram shows the electric field intensity distribution for two cases: when the doping concentration of the absorbing layer 3 is greater than that of the barrier layer and when the doping concentration of the absorbing layer 3 is less than that of the barrier layer. The horizontal axis represents the position (μm) in each layer of the device, and the vertical axis represents the electric field intensity (V / cm).

[0030] At 77K, the doping concentrations of both the electron barrier layer 2 and the hole barrier were set to 1×10⁻⁶. 15 cm -3 The doping concentration of the absorption layer 3 was set to 5×10⁻⁶. 14 cm -3 (Below the barrier layer doping concentration) and 5×10 16 cm -3 Two cases (doping concentration higher than the barrier layer). From... Figure 2 It can be seen that the doping concentration of the absorption layer 3 is 5 × 10⁻⁶. 16 cm -3 The dark current density at that time was 5 × 10⁻⁶ times the doping concentration of the absorption layer 3. 14 cm -3 The dark current density is about an order of magnitude lower at that time.

[0031] exist Figure 3 In the diagram, BCL represents the bottom contact layer 5, HBL represents the hole barrier layer 4, AL represents the absorption layer 3, EBL represents the electron barrier layer 2, and TCL represents the top contact layer 1. In the left figure, the doping concentration of the absorption layer 3 is 5 × 10⁻⁶. 16 cm-3 The doping concentration of the barrier layer is 1×10 15 cm -3 This represents the case where the doping concentration of the absorption layer 3 is greater than that of the barrier layer. In the right figure, the doping concentration of the absorption layer 3 is 5 × 10⁻⁶. 14 cm -3 The doping concentration of the barrier layer is 1×10 15 cm -3 This represents the case where the doping concentration of the absorbing layer 3 is less than that of the barrier layer. From Figure 3 It can be seen that when the doping concentration of the absorption layer 3 is higher than that of the barrier layer, the electric field strength in the absorption layer 3 is suppressed to a very low level, the electric field curve is close to zero, and the electric field is mainly distributed in the barrier layers on both sides of the absorption layer 3.

[0032] Therefore, it can be seen that increasing the doping concentration of the absorption layer 3 (greater than the doping concentration of the barrier layer) will narrow the depletion layer width of the absorption layer 3, causing the depletion region to shift towards the barrier layer, and resulting in a greater drop in electric field falling on the barrier layer. Since the barrier layer has a large band gap, the probability of SRH recombination decreases after the depletion region width of the absorption layer 3 is reduced and the depletion region shifts towards the barrier layer, effectively suppressing the GR current and reducing the overall dark current level.

[0033] Based on the same inventive concept, the present invention also provides a method for fabricating a detector. Figure 4 Please refer to the flowchart of a preparation method provided in an embodiment of the present invention. Figure 1 and Figure 4 This invention employs molecular epitaxial growth technology to fabricate the aforementioned detector in a vacuum cavity, comprising: Step 101: Grow a buffer layer 6 on the substrate 7; Step 102: Grow the bottom contact layer 5 on the buffer layer 6; Step 103: Grow a hole barrier layer 4 on the bottom contact layer 5; Step 104: Grow an absorption layer 3 on the hole barrier layer 4; Step 105: Grow an electronic barrier layer 2 on the absorption layer 3; Step 106: Grow the top contact layer 1 on the electron barrier layer 2.

[0034] Specifically, this invention employs molecular epitaxial growth technology to fabricate the detector in an ultra-high vacuum cavity. Please refer to [reference needed]. Figure 4 First, a buffer layer 6 is grown on the substrate 7 in step 101; a bottom contact layer 5 is grown on the buffer layer 6 in step 102; a hole barrier layer 4 is grown on the bottom contact layer 5 in step 103; an absorption layer 3 is grown on the hole barrier layer 4 in step 104; an electron barrier layer 2 is grown on the absorption layer 3 in step 105; and a top contact layer 1 is grown on the electron barrier layer 2 in step 106.

[0035] Get as Figure 1 The detector structure shown, from bottom to top, consists of a substrate 7, a buffer layer 6, a bottom contact layer 5, a hole barrier layer 4, an absorption layer 3, an electron barrier layer 2, and a top contact layer 1. The superlattice structure effectively reduces dark current, increases operating temperature, and exhibits good material uniformity. Therefore, in this invention, the bottom contact layer 5, hole barrier layer 4, absorption layer 3, electron barrier layer 2, and top contact layer 1 all employ a superlattice structure.

[0036] For example, an InAs / GaSb / AlSb / GaSb superlattice structure is used as the bottom contact layer 5 and the hole barrier layer 4, and an InAs / GaSb superlattice is used as the absorption layer 3, the electron barrier layer 2, and the top contact layer 1. The bottom contact layer 5 is set to be a 18MLInAs / 3MLGaSb / 5MLAlSb / 3MLGaSb superlattice structure with a layer thickness of less than 1 μm, n-type doped, and a doping concentration of 1 × 10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 Hole barrier layer 4 is a superlattice structure of 18 mL InAs / 1 mL GaSb / 5 mL AlSb / 1 mL GaSb with a layer thickness of less than 1 μm, n-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 By setting the bottom contact layer 5 and the hole barrier layer 4 to the same material, not only can good lattice matching between the two be maintained, reducing defects caused by lattice mismatch, but also excellent band continuity between them can be guaranteed.

[0037] Absorber layer 3 is a 15 mL InAs / 6 mL GaSb superlattice structure with a thickness of 2 μm to 6 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 The second electron barrier layer is a superlattice structure of 8 mL InAs / 10 ​​mL GaSb with a thickness of less than 1 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 The top contact layer 1 is a 15 mL InAs / 6 mL GaSb superlattice structure with a thickness of less than 1 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 18 cm -3 Up to 5×10 18 cm-3 .

[0038] By setting the absorption layer 3 to a superlattice structure of 15MLInAs / 6MLGaSb, its bandgap can be made to correspond to the long-wave infrared band. However, it should be noted that setting the absorption layer 3 to a superlattice structure of 15MLInAs / 6MLGaSb is only one structural configuration in this embodiment. In this invention, the layer thickness ratio of InAs to GaSb in the InAs / GaSb superlattice structure of the absorption layer 3 is adjustable, that is, the ratio can also be other values. By adjusting the ratio of the two, the bandgap of the absorption layer 3 can be controlled within the range of 0.088eV to 0.155eV, corresponding to the long-wave infrared band.

[0039] In this embodiment, the thickness of the absorption layer 3 is set to 2 μm to 6 μm to ensure that infrared photons are fully absorbed, achieving high quantum efficiency. Simultaneously, the absorption layer 3 is p-type doped with a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 This narrows the depletion region width within the absorption layer 3, causing it to shift towards the barrier layer and resulting in a greater reduction in the electric field within the barrier layer. Because the barrier layer has a large band gap, the reduced depletion region width and its shift towards the barrier layer decreases the probability of SRH recombination, effectively suppressing GR (generation-recombination) current and lowering the overall dark current level. SRH recombination refers to the recombination of electron-hole pairs through the trap level.

[0040] Increasing the doping concentration of the absorption layer 3 narrows the depletion layer width. Therefore, this invention sets the doping concentration of the absorption layer 3 to be greater than that of the barrier layers (hole barrier layer 4 and electron barrier layer 2). This allows the depletion region to shift towards the barrier layer, resulting in a greater electric field drop occurring on the barrier layer. Because the barrier layer has a large band gap, the reduced depletion region width and shift of the depletion region towards the barrier layer decreases the probability of SRH recombination, effectively suppressing GR current and thus reducing the overall dark current level.

[0041] To visually observe the effect of the doping concentration of the absorption layer 3 on the dark current, simulations were performed in this invention. For example... Figure 2 and Figure 3 As shown. At 77K, the doping concentration of both electron barrier layer 2 and hole barrier layer 4 was set to 1×10⁻⁶. 15 cm -3 The doping concentration of the absorption layer 3 was set to 5×10⁻⁶. 14 cm -3 (Below the barrier layer doping concentration) and 5×10 16cm -3 Two cases (doping concentration higher than the barrier layer). From... Figure 2 It can be seen that the doping concentration of the absorption layer 3 is 5 × 10⁻⁶. 16 cm -3 The dark current density at that time was 5 × 10⁻⁶ times the doping concentration of the absorption layer 3. 14 cm -3 The dark current density is about an order of magnitude lower at that time.

[0042] exist Figure 3 In the middle, left image, the doping concentration of absorption layer 3 is 5 × 10⁻⁶. 16 cm -3 The doping concentration of the barrier layer is 1×10 15 cm -3 This represents the case where the doping concentration of the absorption layer 3 is greater than that of the barrier layer. In the right figure, the doping concentration of the absorption layer 3 is 5 × 10⁻⁶. 14 cm -3 The doping concentration of the barrier layer is 1×10 15 cm -3 This represents the case where the doping concentration of the absorbing layer 3 is less than that of the barrier layer. From Figure 3 It can be seen that when the doping concentration of the absorption layer 3 is higher than that of the barrier layer, the electric field strength in the absorption layer 3 is suppressed to a very low level, the electric field curve is close to zero, and the electric field is mainly distributed in the barrier layers on both sides of the absorption layer 3.

[0043] Therefore, it can be seen that increasing the doping concentration of the absorption layer 3 (greater than the doping concentration of the barrier layer) will narrow the depletion layer width of the absorption layer 3, causing the depletion region to shift towards the barrier layer, and resulting in a greater drop in electric field falling on the barrier layer. Since the barrier layer has a large band gap, the probability of SRH recombination decreases after the depletion region width of the absorption layer 3 is reduced and the depletion region shifts towards the barrier layer, effectively suppressing the GR current and reducing the overall dark current level.

[0044] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0045] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A long-wave infrared detector based on electric field intensity distribution modulation, characterized in that, include: The layers arranged from bottom to top are: substrate, bottom contact layer, hole barrier layer, absorption layer, electron barrier layer, and top contact layer; among which... The bottom contact layer and the hole barrier layer adopt an InAs / GaSb / AlSb / GaSb superlattice structure; the absorption layer, the electron barrier layer and the top contact adopt an InAs / GaSb superlattice structure. The doping concentration of the absorption layer is greater than that of the hole barrier layer and the electron barrier layer.

2. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, The bottom contact layer is a superlattice structure of 18ML InAs / 3ML GaSb / 5ML AlSb / 3ML GaSb, with a layer thickness of less than 1μm, n-type doped, and a doping concentration of 1×10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 .

3. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, The hole barrier layer is a superlattice structure of 18ML InAs / 1ML GaSb / 5ML AlSb / 1ML GaSb, with a layer thickness of less than 1μm, n-type doped, and a doping concentration of 1×10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 .

4. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, The absorption layer is a 15MLInAs / 6MLGaSb superlattice structure with a thickness of 2μm to 6μm, p-type doped, and a doping concentration of 1×10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 .

5. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, The electron barrier layer is an 8 mL InAs / 10 ​​mL GaSb superlattice structure with a thickness of less than 1 μm, p-type doped, and a doping concentration of 1 × 10⁻⁶. 15 cm -3 Up to 9×10 16 cm -3 .

6. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, The top contact layer is a 15ML InAs / 6ML GaSb superlattice structure with a thickness of less than 1μm, p-type doped, and a doping concentration of 1×10⁻⁶. 18 cm -3 Up to 5×10 18 cm -3 .

7. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, The InAs / GaSb superlattice structure of the absorption layer has an adjustable layer thickness ratio of InAs to GaSb, controlling the bandgap of the absorption layer within the range of 0.088eV to 0.155eV.

8. The long-wave infrared detector based on electric field intensity distribution modulation according to claim 1, characterized in that, It also includes a buffer layer located between the substrate and the bottom contact layer.

9. A method for preparing a detector as described in any one of claims 1-8, characterized in that, The molecular epitaxial growth process is performed in a vacuum chamber.

10. The preparation method according to claim 9, characterized in that, include: A buffer layer is grown on the substrate; A bottom contact layer is grown on the buffer layer; A hole barrier layer is grown on the bottom contact layer; An absorption layer is grown on the hole barrier layer; An electron barrier layer is grown on the absorption layer; A top contact layer is grown on the electron barrier layer.

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