Rare bismuth II type superlattice material and preparation method thereof

Abstract

The invention discloses a rare bismuth II type superlattice material and a preparation method thereof. The superlattice material has an InAs (Bi) / GaSb or InAs (Bi) / InAsSb superlattice structure formed by alternately laminating InAs (Bi) layers and GaSb layers or InAsSb layers, and the InAs (Bi) layers are formed by introducing Bi elements into the InAs layers. The preparation method of the superlattice material comprises the following steps: (1) selecting an InSb, InAs or GaSb substrate, performing thermal cleaning on the substrate at 500 DEG C, and cleaning the substrate by using atomic hydrogen in an ultrahigh vacuum environment; (2) alternately laminating InAs (Bi) layers and GaSb layers or InAsSb layers by utilizing a molecular beam epitaxial growth technology, and finally growing a GaSb layer or InAsSb layer as a stop layer, (3) carrying out rapid thermal annealing treatment at the temperature of 380-420 DEG C; the time is 0.5 to 1 min; and (4) characterizing the photoluminescence property of the superlattice. According to the invention, the strain distribution and the energy band structure of the material are obviously improved, the more flexible wavelength regulation and control capability is realized, the hole effective quality is reduced, and the carrier mobility and the quantum efficiency are improved.

Description

Technical Field

[0001] The present invention relates to a superlattice material for infrared detection, in particular to a novel dilute bismuth type II superlattice material and a preparation method thereof, belonging to the field of optoelectronics and semiconductor technology. Background Art

[0002] As an important infrared optoelectronic material, antimonide type II superlattice material has the characteristics of wide spectral modulation, large absorption coefficient, high quantum efficiency and other characteristics in terms of material properties. It has been widely used in military, remote sensing, environment, security and industrial fields. InAs / GaSb and InAs / InAsSb type II superlattice (T2SLs) structure is one of the core materials of current mid-infrared detectors. InAs / GaSb and InAs / InAsSb T2SL structure and energy band are as follows: Figure 1 As shown in the figure. In the InAs / GaSb superlattice system, InAs layers and GaSb layers are arranged alternately to form a type II heterostructure, so that the electron wave function is mainly distributed in the InAs layer, while the hole wave function is mainly distributed in the GaSb layer. The key advantage of this structure is its narrow bandgap characteristic, which enables efficient absorption of mid-wave infrared light. In addition, by adjusting the thickness ratio of the InAs layer and the GaSb layer, the bandgap width can be optimized to meet the needs of infrared detection in different bands. On the other hand, the InAs / InAsSb superlattice material forms a type II band-aligned structure between the InAs layer and the InAsSb layer, in which the bandgap size of InAsSb is adjusted by the introduction of the Sb element. Compared with the InAs / GaSb superlattice, the InAs / InAsSb system avoids the large lattice mismatch between InAs and GaSb, which improves the interface quality of the material. At the same time, by controlling the Sb content in the InAsSb layer, the bandgap of the material can be further adjusted, realizing flexible control of the detector response wavelength range. In terms of growth technology, InAs / GaSb and InAs / InAsSb superlattices are primarily grown using molecular beam epitaxy (MBE). MBE offers high layer thickness accuracy and interface control, resulting in superlattice structures with high crystalline quality.

[0003] In the prior art, III-V superlattice materials (such as InAs / GaSb and InAs / InAsSb) have attracted much attention due to their excellent band control capabilities and wide applications in infrared detectors, quantum devices and other fields. However, these materials have some significant disadvantages in practical applications, which limit their further performance improvement and wider application. First, the strain distribution in existing superlattice materials is uneven. This uneven strain distribution leads to the limitation of the band structure of the material, making it difficult to achieve more flexible band control. In particular, in mid-infrared detection and high-performance quantum devices, the inconsistent offset of the conduction band and the valence band will affect the transport characteristics of the carriers, thereby reducing the performance of the device. Secondly, the effective mass of the holes in the existing superlattice materials is large, which directly leads to a decrease in the carrier mobility, affecting the response speed and quantum efficiency of the device. In infrared detectors, the larger effective mass of the holes will also increase the recombination rate of photogenerated carriers, further reducing the detection sensitivity and response speed. In addition, the quantum efficiency of existing materials is limited by the band structure, which is difficult to meet the needs of high-performance devices. Finally, the strain control methods in existing technologies are relatively simple, mainly relying on the selection of materials and the optimization of growth processes. They lack more flexible and precise control methods and are difficult to adapt to the diverse requirements of material properties in different application scenarios. Summary of the Invention

[0004] In view of the above prior art, the object of the present invention is to provide a new type of dilute bismuth type II superlattice material to achieve more flexible wavelength control capability, reduce the effective mass of holes, and improve carrier mobility and quantum efficiency.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A dilute bismuth type II superlattice material has an InAs(Bi) / GaSb or InAs(Bi) / InAsSb superlattice structure formed by alternating InAs(Bi) layers and GaSb layers or InAsSb layers, wherein the InAs(Bi) layers are formed by introducing Bi elements into the InAs layers.

[0007] Furthermore, the atomic percentage of the Bi component in the InAs(Bi) layer is 1% to 2%; the atomic percentage of the Sb component in the GaSb layer or the InAsSb layer is less than 35%.

[0008] Furthermore, the thickness of the InAs(Bi) layer is 5-10 nm; the thickness of the GaSb layer or the InAsSb layer is 5-10 nm.

[0009] Furthermore, the number of alternating stacking cycles of the InAs(Bi) layer and the GaSb layer or the InAsSb layer in the superlattice material is 200-300.

[0010] A method for preparing the dilute bismuth type II superlattice material comprises the following steps:

[0011] (1) Substrate selection and pretreatment

[0012] Select InSb, InAs, or GaSb substrates and perform thermal cleaning at 500°C to remove surface oxides. Use atomic hydrogen cleaning in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0013] (2) Superlattice growth

[0014] The InAs(Bi) / GaSb or InAs(Bi) / InAsSb superlattice structure is grown using molecular beam epitaxy technology, with InAs(Bi) layers and GaSb layers or InAsSb layers alternately stacked, and finally a GaSb layer or InAsSb layer is grown as a termination layer. The growth process parameters for each layer are:

[0015] InAs (Bi) layer: growth temperature is 360℃~400℃; In beam current is 0.8~1.2×10 -7 Torr; As beam current is 1.5~3.0×10 -6 Torr; Bi beam current is 1.0~5.0×10 -8 Torr; growth rate is 0.3-0.5 μm / h;

[0016] GaSb layer: Growth temperature is 450-490°C; Ga beam current is 0.8-1.1×10 -7 Torr; Sb beam current is 1.5~3.0×10 -6 Torr; growth rate is 0.5-0.8 μm / h;

[0017] InAsSb layer: Growth temperature is 400-420°C; In beam current is 0.8-1.2×10 -7 Torr; As beam current is 1.5~3.0×10 -6 Torr; Sb beam current is 1.5~3.0×10 -6 Torr; growth rate is 0.4-0.6 μm / h;

[0018] (3) Post-processing

[0019] Rapid thermal annealing treatment: temperature is 380-420°C; time is 0.5-1 min;

[0020] (4) Characterization

[0021] The photoluminescence properties of the superlattice were characterized using Fourier transform infrared spectroscopy.

[0022] Furthermore, in step (1), an InSb substrate is preferred because its lattice constant is more compatible with InAs(Bi) and GaSb / InAsSb. If an InAs or GaSb substrate is used, an AlSb buffer layer needs to be grown to balance the strain, alleviate the lattice mismatch between the substrate and the superlattice, and improve the quality of the epitaxial layer.

[0023] Furthermore, the growth process of the AlSb buffer layer is as follows: growth temperature is 480-520° C., growth rate is 0.5-0.8 μm / h, and thickness is 0.3-0.8 μm.

[0024] Beneficial effects of the present invention:

[0025] By introducing Bi into the InAs layer to form InAs(Bi) / GaSb and InAs(Bi) / InAsSb superlattice structures, this invention significantly improves the material's strain distribution and band structure, enabling more flexible wavelength control, reducing the effective hole mass, and improving carrier mobility and quantum efficiency. Compared to existing technologies, this invention offers significant advantages in strain control flexibility, carrier transport properties, and quantum efficiency enhancement, providing a new material foundation for the development of high-performance infrared detectors and quantum devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the InAs / GaSb and InAs / InAsSb T2SL structures and energy bands.

[0027] Figure 2 Schematic diagram of the InAs(Bi) / GaSb and InAs(Bi) / InAsSb superlattice band structures.

[0028] Figure 3 This is the photoluminescence performance curve of the superlattice material of Example 1.

[0029] Figure 4 This is the photoluminescence performance curve of the superlattice material of Example 2.

[0030] Figure 5 This is the photoluminescence performance curve of the superlattice material of Example 3.

[0031] Figure 6 This is the photoluminescence performance curve of the superlattice material of Example 4.

[0032] Figure 7 This is the photoluminescence performance curve of the superlattice material of Example 5.

[0033] Figure 8 This is the photoluminescence performance curve of the superlattice material of Example 6.

[0034] Figure 9 This is the photoluminescence performance curve of the superlattice material of Comparative Example 1.

[0035] Figure 10 This is the photoluminescence performance curve of the superlattice material of Comparative Example 2. DETAILED DESCRIPTION

[0036] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. The embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0037] While conventional InAs / GaSb and InAs / InAsSb superlattice technologies have demonstrated excellent performance in infrared detectors and quantum devices, limitations in their strain distribution and band structure restrict their further application. Furthermore, the large effective hole mass in existing technologies leads to low carrier mobility, further limiting the device's response speed and detection sensitivity. In particular, in mid-wave infrared detection applications, the performance of existing materials struggles to meet the growing demand for high performance.

[0038] The present invention provides an effective technical approach to solve the above problems by introducing Bi into the InAs layer to form InAs(Bi) / GaSb and InAs(Bi) / InAsSb superlattice structures. The introduction of Bi brings the following significant advantages:

[0039] (1) Optimization of strain distribution

[0040] In traditional InAs / GaSb and InAs / InAsSb superlattices, the tensile strain of the InAs layer and the compressive strain distribution of the GaSb layer (or InAsSb layer) limit the band control ability of the material. This uneven strain distribution leads to inconsistent offsets of the conduction band and the valence band, affecting the carrier transport characteristics. In addition, the prior art lacks flexible strain control methods, making it difficult to achieve more precise band engineering. The present invention introduces Bi elements into the InAs layer to form InAs(Bi) / GaSb and InAs(Bi) / InAsSb superlattice structures. The introduction of Bi elements changes the lattice constant of the InAs layer, causing it to change from the original tensile strain to compressive strain. At the same time, the strain type of the GaSb layer or the InAsSb layer is also changed from compressive strain to tensile strain. In addition, the introduction of Bi elements into the InAs layer increases the lattice constant of the InAs layer and reduces the lattice mismatch. This precise control of strain distribution optimizes the material's band structure, reduces interface strain accumulation, thereby reducing defect density, improving the long-term stability of the device, and achieving more flexible wavelength control capabilities, making it more suitable for the needs of high-performance devices. The band diagram is shown in the figure. Figure 2 shown.

[0041] (2) Reduction of effective hole mass

[0042] Due to the unevenness of strain distribution, the effective mass of holes in traditional superlattice materials is large, resulting in low carrier mobility. This not only affects the response speed of the device, but also increases the recombination rate of photogenerated carriers, reducing detection sensitivity and quantum efficiency. In infrared detectors, the large effective mass of holes directly limits the performance improvement of the device. The present invention significantly reduces the effective mass of holes and thus improves carrier mobility by introducing Bi elements and optimizing strain distribution. This improvement not only improves the response speed of the device, but also reduces the recombination rate of photogenerated carriers, which is manifested in infrared detectors as a significant improvement in detection sensitivity and response speed.

[0043] (3) Improvement of quantum efficiency:

[0044] The band structure of traditional superlattice materials is limited by strain distribution, making it difficult to further improve quantum efficiency. This invention significantly improves quantum efficiency by optimizing the band structure of superlattice materials, making them perform better in mid-wave infrared detection and high-performance quantum devices.

[0045] Design and preparation of InAs(Bi) / GaSb and InAs(Bi) / InAsSb superlattice materials of the present invention

[0046] 1. Band design

[0047] In the development of superlattice materials, the first thing to do is to carry out energy band design and determine the material's energy band structure, strain distribution and component parameters through theoretical calculations.

[0048] (1) Target band structure:

[0049] The design goal is to optimize the band structure of InAs(Bi) / GaSb and InAs(Bi) / InAsSb superlattices by introducing Bi elements, forming a broken gap structure, improving the spatial separation of electrons and holes, reducing the effective mass of holes, and improving quantum efficiency.

[0050] (2) Strain distribution optimization:

[0051] The composition of Bi is determined through theoretical calculations, so that the InAs(Bi) layer is transformed from tensile strain to compressive strain, and at the same time, the GaSb layer or the InAsSb layer is transformed from compressive strain to tensile strain.

[0052] (3) Component and thickness design:

[0053] The composition, thickness, and number of superlattice periods of the InAs(Bi) layer and the GaSb / InAsSb layer are determined to achieve target band coverage.

[0054] 2. Molecular beam epitaxy (MBE) growth

[0055] After completing the energy band design, the epitaxial growth of the superlattice material is achieved through molecular beam epitaxy (MBE) technology.

[0056] 3. Characterization

[0057] The photoluminescence (PL) performance of the superlattice was characterized using Fourier transform infrared spectroscopy. The photoluminescence (PL) results of the embodiment and the comparative example were analyzed and compared to verify the effect of the introduction of Bi on the luminescence performance of the superlattice.

[0058] Example 1

[0059] This embodiment provides a method for preparing an InAs(Bi) / GaSb superlattice.

[0060] (1) Substrate selection and pretreatment

[0061] An InSb substrate was thermally cleaned at 500°C for 10-15 minutes to remove surface oxides. Atomic hydrogen cleaning was then performed at 450°C in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0062] (2) Superlattice epitaxial growth

[0063] InAs(Bi) layer:

[0064] Bi component: 1%.

[0065] Growth temperature: 380℃.

[0066] In beam current: 1.0×10 -7 Torr.

[0067] As beam current: 3.0×10 -6 Torr.

[0068] Bi beam current: 1.0×10 -8 Torr.

[0069] Growth rate: 0.3 μm / h.

[0070] Thickness: 7nm.

[0071] GaSb layer:

[0072] Growth temperature: 450℃.

[0073] Ga beam current: 1.0×10 -7Torr.

[0074] Sb beam current: 3.0×10 -6 Torr.

[0075] Growth rate: 0.6 μm / h.

[0076] Thickness: 7nm.

[0077] Number of cycles: 200 cycles.

[0078] Termination layer: Finally, a layer of GaSb is grown as the termination layer with a thickness of 10nm.

[0079] (3) Post-processing

[0080] Rapid thermal annealing treatment:

[0081] Temperature: 400℃.

[0082] Time: 1 minute.

[0083] Purpose: To improve crystal quality and reduce defects.

[0084] Characterization:

[0085] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 3 As shown, the luminescence center peak is at 6.5μm, with a high signal-to-noise ratio and good luminescence performance.

[0086] Example 2

[0087] The difference between this embodiment and embodiment 1 is that an InAs substrate is selected as the substrate.

[0088] (1) Substrate pretreatment:

[0089] The substrate was thermally cleaned at 550°C for 10-15 minutes to remove surface oxides, and then cleaned with atomic hydrogen at 450°C in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0090] (2) AlSb buffer layer growth

[0091] Growth temperature: 500℃.

[0092] Growth rate: 0.5 μm / h.

[0093] Thickness: 0.8μm.

[0094] Purpose: To alleviate the lattice mismatch between the substrate and the superlattice and improve the quality of the epitaxial layer.

[0095] The subsequent superlattice epitaxial growth is consistent with that in Example 1.

[0096] Characterization:

[0097] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 4 As shown, the luminescence center peak is at 5.8μm, with a high signal-to-noise ratio and good luminescence performance.

[0098] Example 3

[0099] The difference between this embodiment and embodiment 1 is that a GaSb substrate is selected as the substrate.

[0100] (1) Substrate pretreatment:

[0101] The substrate was thermally cleaned at 550°C for 10-15 minutes to remove surface oxides, and then cleaned with atomic hydrogen at 450°C in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0102] (2) AlSb buffer layer growth

[0103] Growth temperature: 500℃.

[0104] Growth rate: 0.5 μm / h.

[0105] Thickness: 0.8μm.

[0106] Purpose: To alleviate the lattice mismatch between the substrate and the superlattice and improve the quality of the epitaxial layer.

[0107] The subsequent superlattice epitaxial growth is consistent with that in Example 1.

[0108] Characterization:

[0109] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 5 As shown, the luminescence center peak is at 5.9μm, with a high signal-to-noise ratio and good luminescence performance.

[0110] Example 4

[0111] This embodiment provides a method for preparing an InAs(Bi) / InAsSb superlattice.

[0112] (1) Substrate selection and pretreatment

[0113] An InSb substrate was thermally cleaned at 500°C for 10-15 minutes to remove surface oxides. Atomic hydrogen cleaning was then performed at 450°C in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0114] (2) Superlattice epitaxial growth

[0115] InAs(Bi) layer:

[0116] Bi component: 1%

[0117] Growth temperature: 380℃.

[0118] In beam current: 1.0×10 -7 Torr.

[0119] As beam current: 3.0×10 -6 Torr.

[0120] Bi beam current: 1.0×10 -8 Torr.

[0121] Growth rate: 0.3 μm / h.

[0122] Thickness: 7nm.

[0123] InAsSb layer:

[0124] Sb component: 35%

[0125] Growth temperature: 400℃.

[0126] In beam current: 1.0×10 -7 Torr.

[0127] As beam current: 3.0×10 -6 Torr.

[0128] Sb beam current: 2.0×10 -6 Torr.

[0129] Growth rate: 0.3 μm / h.

[0130] Thickness: 7.2nm.

[0131] Number of cycles: 200 cycles.

[0132] Termination layer: Finally, a layer of InAsSb is grown as the termination layer with a thickness of 10 nm.

[0133] (3) Post-processing

[0134] Rapid thermal annealing treatment:

[0135] Temperature: 400℃.

[0136] Time: 1 minute.

[0137] Purpose: To improve crystal quality and reduce defects.

[0138] Characterization:

[0139] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 6 As shown, the luminescence center peak is at 6μm, with a high signal-to-noise ratio and good luminescence performance.

[0140] Example 5

[0141] The difference between this embodiment and embodiment 4 is that an InAs substrate is selected as the substrate.

[0142] (1) Substrate pretreatment:

[0143] The substrate was thermally cleaned at 550°C for 10-15 minutes to remove surface oxides, and then cleaned with atomic hydrogen at 450°C in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0144] (2) AlSb buffer layer growth

[0145] Growth temperature: 500℃.

[0146] Growth rate: 0.5 μm / h.

[0147] Thickness: 0.8μm.

[0148] Purpose: To alleviate the lattice mismatch between the substrate and the superlattice and improve the quality of the epitaxial layer.

[0149] The subsequent superlattice epitaxial growth is consistent with that of Example 4.

[0150] Characterization:

[0151] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 7 As shown, the luminescence center peak is at 5.6μm, with a high signal-to-noise ratio and good luminescence performance.

[0152] Example 6

[0153] The difference between this embodiment and embodiment 4 is that a GaSb substrate is selected as the substrate.

[0154] (1) Substrate pretreatment:

[0155] The substrate was thermally cleaned at 550°C for 10-15 minutes to remove surface oxides, and then cleaned with atomic hydrogen at 450°C in an ultra-high vacuum (UHV) environment to further remove surface contaminants.

[0156] (2) AlSb buffer layer growth

[0157] Growth temperature: 500℃.

[0158] Growth rate: 0.5 μm / h.

[0159] Thickness: 0.8μm.

[0160] Purpose: To alleviate the lattice mismatch between the substrate and the superlattice and improve the quality of the epitaxial layer.

[0161] The subsequent superlattice epitaxial growth is consistent with that of Example 4.

[0162] Characterization:

[0163] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 8 As shown, the luminescence center peak is at 5.6μm, with a high signal-to-noise ratio and good luminescence performance.

[0164] Comparative Example 1

[0165] The difference between this comparative example and Example 2 is that Bi is not introduced, and the InAs / GaSb superlattice is epitaxially grown under the same other conditions.

[0166] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 9 As shown, the luminescence center peak is at 6.4μm, the signal-to-noise ratio is low, and the luminescence performance is slightly poor, indicating that the radiative recombination is weakened and the quantum efficiency is reduced.

[0167] Comparative Example 2

[0168] The difference between this comparative example and Example 5 is that Bi is not introduced, and the InAs / InAsSb superlattice is epitaxially grown under the same other conditions.

[0169] The photoluminescence properties of the superlattice were characterized using a Fourier transform infrared spectrometer at 75K-100mW. Figure 9 As shown, the luminescence center peak is at 5.3μm, the signal-to-noise ratio is low, and the luminescence performance is slightly poor, indicating that the radiative recombination is weakened and the quantum efficiency is reduced.

[0170] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the above embodiments describe the present invention in detail, relevant technical personnel in the field should understand that the present invention can be modified or replaced by equivalents, but any modifications and partial replacements that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A dilute bismuth type II superlattice material, characterized in that: The superlattice material has an InAs(Bi) / GaSb or InAs(Bi) / InAsSb superlattice structure formed by alternately stacking InAs(Bi) layers and GaSb layers or InAsSb layers, wherein the InAs(Bi) layers are formed by introducing Bi elements into the InAs layers.

2. The superlattice material according to claim 1, characterized in that The atomic percentage of the Bi component in the InAs(Bi) layer is 1% to 2%; the atomic percentage of the Sb component in the GaSb layer or the InAsSb layer is less than 35%.

3. The superlattice material according to claim 1, characterized in that The thickness of the InAs(Bi) layer is 5-10 nm; the thickness of the GaSb layer or the InAsSb layer is 5-10 nm.

4. The superlattice material according to claim 1, characterized in that The number of alternating stacking cycles of the InAs(Bi) layer and the GaSb layer or the InAsSb layer in the superlattice material is 200-300.

5. A method for preparing the superlattice material according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Substrate selection and pretreatment Select InSb, InAs, or GaSb substrates and perform thermal cleaning at 500°C to remove surface oxides. Use atomic hydrogen cleaning in an ultra-high vacuum (UHV) environment to further remove surface contaminants. (2) Superlattice growth The InAs(Bi) / GaSb or InAs(Bi) / InAsSb superlattice structure is grown using molecular beam epitaxy technology, with InAs(Bi) layers and GaSb layers or InAsSb layers alternately stacked, and finally a GaSb layer or InAsSb layer is grown as a termination layer. The growth process parameters for each layer are: InAs (Bi) layer: growth temperature is 360℃~400℃; In beam current is 0.8~1.2×10 -7 Torr; As beam current is 1.5~3.0×10 -6 Torr; Bi beam current is 1.0~5.0×10 -8 Torr; growth rate is 0.3-0.5 μm / h; GaSb layer: Growth temperature is 450-490°C; Ga beam current is 0.8-1.1×10 -7 Torr; Sb beam current is 1.5~3.0×10 -6 Torr; growth rate is 0.5-0.8 μm / h; InAsSb layer: Growth temperature is 400-420°C; In beam current is 0.8-1.2×10 -7 Torr; As beam current is 1.5~3.0×10 -6 Torr; Sb beam current is 1.5~3.0×10 -6 Torr; growth rate is 0.4-0.6 μm / h; (3) Post-processing Rapid thermal annealing treatment: temperature is 380-420°C; time is 0.5-1 min; (4) Characterization The photoluminescence properties of the superlattice were characterized using Fourier transform infrared spectroscopy.

6. The method for preparing a superlattice material according to claim 5, characterized in that: In the step (1), an InSb substrate is selected.

7. The method for preparing a superlattice material according to claim 5, characterized in that: In the step (1), an InAs or GaSb substrate is selected, and an AlSb buffer layer is pre-grown on the substrate to balance the strain.

8. The method for preparing a superlattice material according to claim 7, characterized in that: The growth process of the AlSb buffer layer is as follows: a growth temperature of 480-520° C., a growth rate of 0.5-0.8 μm / h, and a thickness of 0.3-0.8 μm.

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