Silicon-based PbSe single crystal film, preparation method thereof and infrared photoelectric detector

Abstract

The invention belongs to the technical field of material growth, and particularly relates to a silicon-based PbSe single crystal thin film and a preparation method thereof and an infrared photoelectric detector, the silicon-based PbSe single crystal thin film comprises a substrate, a graphene layer and a PbSe thin film layer, and the substrate is a silicon or silicon dioxide substrate; the surface roughness of the silicon-based PbSe single crystal thin film ranges from 4 nm to 10 nm, the defect density ranges from 0.8 nm <-2 > to 1.2 nm <-2 >, and the half-peak width ranges from 0.15 degree to 0.2 degree. The preparation method comprises the following steps: transferring at least one layer of graphene to the surface of a silicon substrate or a silicon dioxide substrate by adopting a wet transfer process to form a graphene layer; and epitaxially growing a PbSe thin film layer on the graphene layer by adopting a chemical vapor deposition method. The method has the beneficial effects that the PbSe film which is high in quality, excellent in single crystal property and flat in surface on a functional substrate (silicon / silicon dioxide) is obtained, meanwhile, the excellent surface flatness is more beneficial to application of an array process, and application of a silicon-based PbSe large-area array is expected to be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of material growth, and in particular relates to a silicon-based PbSe single crystal film and a preparation method thereof, and an infrared photoelectric detector. Background Art

[0002] Lead salt thin films have been widely used in infrared detection, satellite sensing, and meteorological monitoring due to their high carrier mobility, strong light-matter interaction, and excellent photoelectric conversion efficiency. Lead salt infrared detectors have a high detection rate in the 3-5μm atmospheric window at room temperature, so they have excellent detection performance for short- and medium-wave infrared light.

[0003] In recent years, due to the diversity of preparation processes and the increasing selectivity of substrate adaptation, lead salt semiconductors can be perfectly heteroepitaxially grown on other special substrates such as strontium titanate, mica and ITO. This has led to the discovery of the physics of high-quality single-crystalline lead salt films and the efficient photoelectric conversion characteristics of infrared detectors prepared from them.

[0004] Since there is the possibility of monolithic integration between the readout electronic devices integrated with silicon, it has a broader prospect in the civilian market because it can be mass-produced at low cost. However, due to the limitations of existing processes, the thin films grown on silicon substrates by PbSe are basically polycrystalline thin films, and single-crystalline PbSe with good performance cannot be directly grown on silicon or silicon dioxide, which results in PbSe not being able to obtain good performance on the most widely used functional substrates, silicon or silicon dioxide. Although polycrystalline nanofilms can be compatible with silicon-based integration processes through sensitization treatment and obtain good photoconductivity response signals, the intrinsic carrier scattering and defects caused by polycrystalline films have caused polycrystalline PbSe films on silicon substrates to never reach the high performance level of other epitaxially grown films.

[0005] Therefore, how to grow single-crystalline PbSe on silicon or silicon dioxide and obtain good performance is a technical problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a silicon-based PbSe single crystal film and a preparation method thereof and an infrared photodetector.

[0007] The technical solution of the present invention is as follows: A first aspect of the present invention provides a silicon-based PbSe single crystal thin film, comprising a substrate, a graphene layer disposed on the substrate, and a PbSe thin film layer disposed on the graphene layer, wherein the substrate is a silicon substrate or a silicon dioxide substrate; Wherein, the surface roughness of the silicon-based PbSe single crystal film is 4nm~10nm; The defect density of the silicon-based PbSe single crystal film is 0.8 nm -2 ~1.2nm -2 ; The half-peak width of the silicon-based PbSe single crystal film is 0.15°~0.2°.

[0008] Optionally, the silicon-based PbSe single crystal thin film has a (200) crystal plane orientation.

[0009] Optionally, the thickness of the graphene layer is 0.3 nm to 1.2 nm.

[0010] Optionally, the thickness of the graphene layer is 0.3nm~0.4nm.

[0011] Optionally, the thickness of the PbSe thin film layer is 80 nm to 100 nm.

[0012] Optionally, the silicon crystal plane of the substrate is a (100) plane.

[0013] A second aspect of the present invention provides a method for preparing a PbSe single crystal thin film by self-assembly growth on a silicon / silicon dioxide substrate, comprising the following steps: Transferring at least one layer of graphene to the surface of a silicon substrate or a silicon dioxide substrate by a wet transfer process, forming a graphene layer on the surface of the silicon substrate or the silicon dioxide substrate, and obtaining a silicon substrate or a silicon dioxide substrate with a graphene layer; PbSe is epitaxially grown on the graphene layer by a chemical vapor deposition method to form a PbSe thin film layer, thereby obtaining a silicon-based PbSe single crystal thin film.

[0014] Optionally, the method of transferring at least one layer of graphene to the surface of a silicon substrate or a silicon dioxide substrate using a wet transfer process specifically comprises the following steps: The surface of the single-layer or multi-layer graphene grown on the copper foil is coated with PMMA (polymethyl methacrylate), and after drying, it is immersed in a KOH solution until the PMMA floats; The floating PMMA is scooped up using a silicon substrate or a silicon dioxide substrate, rinsed with water and then dried, and finally immersed in an acetone solution, rinsed with water and blown dry to form a graphene layer on the surface of the silicon substrate or the silicon dioxide substrate to obtain a silicon substrate or a silicon dioxide substrate with a graphene layer.

[0015] Optionally, the mass fraction of the KOH solution is 15% to 25%, and the immersion time in the acetone solution is 1 h to 2 h.

[0016] Optionally, the method for epitaxially growing PbSe on the graphene layer specifically comprises the following steps: Along the flow direction of the carrier gas from upstream to downstream, using PbSe powder as an evaporation source material and Se powder as a supplementary source, setting the silicon substrate or silicon dioxide substrate with a graphene layer, evacuating, first heating, then keeping the temperature, and finally cooling to form a PbSe thin film layer; The heating temperatures of the Se powder and the PbSe powder are 250°C to 350°C and 700°C to 750°C respectively, the heating rate is ≤10°C / min, and the time from room temperature to the heating temperature is 70min to 80min; The heating temperature of the silicon substrate or silicon dioxide substrate with the graphene layer is 300° C. to 400° C.; The insulation time is 4min~8min; The vacuum is evacuated to a vacuum degree of 1×10 -3 Pa~1×10 -2 Pa, control the carrier gas flow rate to 10sccm~20sccm; The PbSe powder and Se powder are mixed in a mass ratio of 1-2:2-4.

[0017] A third aspect of the present invention provides an infrared photodetector comprising the above-mentioned silicon-based PbSe single crystal thin film.

[0018] Through testing, it was found that the PbSe device on silicon can still achieve a photoelectric response of microamperes under microwatt-level optical power conditions, demonstrating its reliability in the field of infrared photoelectric detection.

[0019] The present invention has at least one of the following beneficial effects: The present invention first forms a graphene layer on the surface of a silicon / silicon dioxide substrate by a wet transfer process, and then grows a PbSe film on the silicon / silicon dioxide substrate with the graphene layer by a chemical vapor deposition method, and obtains a PbSe film with a smooth surface, high thickness uniformity, and obvious single crystal diffraction peak by controlling growth parameters.

[0020] The present invention forms a graphene layer on the surface of a silicon / silicon dioxide substrate first, and then grows a PbSe film on the graphene layer, thereby obtaining a high-quality PbSe film with excellent single crystallinity and smooth surface on a functional substrate (silicon / silicon dioxide), thereby solving the problem that single crystal PbSe with good performance cannot be directly grown on a silicon or silicon dioxide substrate in the prior art. Compared with the prior art of directly growing single crystal PbSe on a silicon or silicon dioxide substrate, the silicon-based PbSe single crystal film prepared by the present invention not only has the advantages of low roughness, high density, excellent single crystallinity, etc., but also has excellent surface flatness that is more conducive to the application of array technology, and is expected to realize the commercial application of silicon-based PbSe large-area arrays. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the process of transferring graphene and growing PbSe on the silicon / silicon dioxide surface in Invention Examples 1 and 2.

[0022] Figure 2 These are scanning electron microscope surface morphology images of PbSe grown with a single layer of graphene in Example 1 of the present invention and PbSe grown without graphene in Comparative Example 1; wherein, a is a scanning electron microscope surface morphology image of PbSe grown with a single layer of graphene in Example 1, and b is a scanning electron microscope surface morphology image of PbSe grown without graphene in Comparative Example 1.

[0023] Figure 3 These are the surface roughness characterization graphs of PbSe grown with a single layer of graphene in Example 1 of the present invention and PbSe grown without graphene in Comparative Example 1; wherein, a is the surface roughness characterization graph of PbSe grown with a single layer of graphene in Example 1, and b is the surface roughness characterization graph of PbSe grown without graphene in Comparative Example 1.

[0024] Figure 4 These are transmission electron microscopy characterization images of PbSe grown with a single layer of graphene in Example 1 of the present invention and PbSe grown without graphene in Comparative Example 1; wherein, a is a transmission electron microscopy characterization image of PbSe grown with a single layer of graphene in Example 1, and b is a transmission electron microscopy characterization image of PbSe grown without graphene in Comparative Example 1.

[0025] Figure 5 1 and 2 are the X-ray diffraction patterns of PbSe grown with a single layer of graphene in Example 1 of the present invention and PbSe grown without graphene in Comparative Example 1.

[0026] Figure 6 The mid-wave infrared detection performance of PbSe grown with single-layer graphene in Example 1 of the present invention is characterized.

[0027] Figure 7 This is a scanning electron microscope surface morphology image of PbSe grown with double-layer graphene in Example 2 of the present invention.

[0028] Figure 8 This is the X-ray diffraction pattern of PbSe grown with double-layer graphene in Example 2 of the present invention. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] An embodiment of the present invention provides a silicon-based PbSe single crystal film, which mainly comprises: silicon / silicon dioxide with a (100) crystal plane as a substrate, at least one layer of graphene transferred on the surface of the silicon / silicon dioxide, and a PbSe thin film layer epitaxially grown on the graphene: In some embodiments, the substrate is silicon / silicon dioxide with a growth crystal plane of (100), and the oxide layer thickness on the surface of the silicon / silicon dioxide substrate is preferably 200 nm to 400 nm, and the oxide layer thickness is more preferably 300 nm.

[0031] In some embodiments, the thickness of the single-layer graphene film layer is 0.3 nm to 0.4 nm.

[0032] In some embodiments, 1 to 3 layers of graphene are transferred onto the silicon / silicon dioxide surface.

[0033] Another embodiment of the present invention provides a method for preparing a PbSe single crystal thin film by self-assembly growth on a silicon / silicon dioxide substrate, comprising the following steps: Transferring graphene to a silicon / silicon dioxide substrate: transferring at least one layer of graphene to a surface of a silicon substrate or a silicon dioxide substrate using a wet transfer process to form a graphene layer on the surface of the silicon substrate or the silicon dioxide substrate; Growing a PbSe thin film: epitaxially growing PbSe on the graphene layer by a chemical vapor deposition method to form a PbSe thin film layer, thereby obtaining a silicon-based PbSe single crystal thin film.

[0034] In some embodiments, the method of transferring graphene to a silicon / silicon dioxide substrate mainly includes: A layer of PMMA is uniformly coated on the surface of the single-layer or multi-layer graphene grown on the copper foil, and the PMMA is dried by heating it to 100°C on a heating table for 20min~30min; a KOH solution with a mass fraction of 15%~25% is prepared by mixing KOH powder and deionized water in a mass ratio of 1:4~6; PMMA is immersed until it floats on the KOH solution, and PMMA will carry the single-layer or multi-layer graphene film to float on the surface of the KOH solution.

[0035] Use a clean silicon / silicon dioxide substrate to pick up the PMMA, deionize it and place it on a heating table at 60°C to dry it; soak the silicon / silicon dioxide substrate with PMMA in acetone solution for 1h~2h, rinse it with water and blow it dry to obtain the silicon / silicon dioxide substrate with a single layer of graphene transferred.

[0036] In some embodiments, growing a PbSe thin film on a silicon / silicon dioxide substrate onto which a single-layer graphene is transferred comprises the following steps: PbSe and Se powders are used as raw materials to grow a single-layer graphene film on the surface of a silicon / silicon dioxide substrate by chemical vapor deposition; the chemical vapor deposition includes a heating stage, a deposition stage and a cooling stage; the flow rate of the carrier gas during the chemical vapor deposition process is preferably 10 sccm.

[0037] In some embodiments, the chemical vapor deposition includes the following steps: along the flow direction of the carrier gas from upstream to downstream, a Se powder evaporation source, a PbSe powder evaporation source and a silicon / silicon dioxide substrate with a graphene film are sequentially arranged; the heating temperature of the Se powder evaporation source is 300°C, the heating temperature of the PbSe powder evaporation source is 750°C, and the heating temperature of the silicon substrate or the silicon dioxide substrate is 300°C~400°C; the heating rate of the mixed powder in the heating stage is ≤10°C / min.

[0038] In some embodiments, the holding time of the deposition stage is 4 min to 8 min; and the deposition thickness of the PbSe single crystal film layer is 80 nm to 100 nm.

[0039] In some embodiments, the raw material powder used to grow the PbSe thin film is preferably a mixed powder of PbSe powder and Se powder in a mass ratio of 1:2.

[0040] In some embodiments, the thickness of the PbSe film grown on a silicon substrate or a silicon dioxide surface is preferably 80 nm.

[0041] In some embodiments, the PbSe grown on the silicon / silicon dioxide substrate onto which the graphene is transferred has a smoother surface and a more uniform crystal orientation as viewed from a scanning electron microscope image.

[0042] In some embodiments, the surface roughness of PbSe grown on a silicon / silicon dioxide substrate with graphene transferred thereto is lower in the same scanning range as scanned by the step meter. In some embodiments, the quality of the grown PbSe thin film crystals can be clearly determined by the position of the XRD diffraction peaks, and differences in peak position and size can be found between PbSe grown on a silicon / silicon dioxide substrate with transferred graphene and PbSe grown directly on silicon / silicon dioxide.

[0043] In some embodiments, the self-assembled growth of PbSe single crystal thin film by transferring graphene on a silicon / silicon dioxide substrate has excellent photoelectric detection properties. The characterization methods used include X-ray diffraction spectra, scanning electron microscope morphology images and various electrical test source tables.

[0044] The present invention is further described in detail below with specific examples, but the present invention is not limited to the following specific examples.

[0045] Example 1 This embodiment provides a method for preparing a PbSe single crystal thin film by transferring graphene onto a silicon dioxide substrate to achieve self-assembly growth. The process flow is as follows: Figure 1 As shown, the specific steps include: (1) Transferring single-layer graphene.

[0046] Buy a single layer of graphene on copper foil and evenly coat a layer of PMMA (polymethyl methacrylate) on its surface. You can use a rotating table set to a speed of 600r / min for 1 minute to make it more uniform. Then place the copper foil with PMMA spin-coated on a heating table and set the heating table temperature to 100℃ for 30 minutes to solidify the PMMA.

[0047] Take KOH powder and deionized water in a mass ratio of 1:5 to prepare a 20% KOH solution, and immerse the copper foil with PMMA in the KOH solution. After 2 hours, PMMA will carry a single-layer graphene film and float on the surface of the KOH solution.

[0048] Take a clean silica substrate and pick up the PMMA. The PMMA will carry a single-layer graphene film attached to the silicon substrate; rinse with deionized water and dry on a heating table at 60°C. Then, soak the silica substrate with PMMA in acetone solution for 1 hour, rinse with water and blow dry to form a graphene / silicon substrate, that is, obtain a silica substrate with a single-layer graphene transferred.

[0049] (2) Growth of PbSe thin film.

[0050] Along the flow direction of the carrier gas from upstream to downstream, 0.2 g of PbSe (99.99%) was placed in the center of a horizontal tube furnace with a diameter of 12 inches as an evaporation source material, and 0.4 g of selenium powder was placed in the front of the furnace as a supplementary source. The silicon dioxide substrate with the transferred single-layer graphene was placed at the end of the furnace 10 cm away from the outlet. After the tube furnace was sealed, a mechanical pump and a molecular pump were used to evacuate the vacuum to a vacuum degree of 1×10 -3 Pa, and the carrier gas flow rate was controlled to be 10 sccm. The heating temperature of the selenium powder supplement source was 300°C, the heating temperature of the PbSe powder was set to 750°C, and the temperature of the silicon dioxide substrate to which the single-layer graphene was transferred was set to 450°C; the time for the tubular furnace to heat up from room temperature to the heating temperature of the PbSe powder (750°C) was 75 minutes, and the steam formed by the reaction source and the selenium powder supplement source was transported by the carrier gas to the surface of the silicon dioxide substrate to which the single-layer graphene was transferred to react for 6 minutes, and then the heating power of the tubular furnace was cut off, and the furnace body was naturally cooled to room temperature to obtain a single-crystalline PbSe film.

[0051] This method can successfully grow a PbSe film on a silicon dioxide substrate, solving the problem in the prior art that a PbSe single crystal film with good performance cannot be obtained on a silicon or silicon dioxide substrate.

[0052] Comparative Example 1 The only difference from Example 1 is that step (1) is not performed, and the PbSe film is grown directly on the surface of the silicon dioxide substrate according to the method of step (2).

[0053] The performance of the PbSe film of the transferred single-layer graphene prepared in Example 1 and the PbSe film prepared in Comparative Example 1 was tested, and the test results are as follows: The scanning electron microscopy results of the PbSe film of the transferred single-layer graphene prepared in Example 1 and the PbSe film prepared in Comparative Example 1 are as follows: Figure 2 As shown in the figure, it can be seen that the PbSe film ( Figure 2 The surface density of a) is significantly better than that of the PbSe film grown directly on the silicon dioxide substrate prepared in Comparative Example 1 ( Figure 2 b), which shows that by first forming a graphene layer on a silicon or silicon dioxide substrate and then growing a PbSe film on the graphene layer, it helps to make the PbSe growth orientation consistent while ensuring that a single crystal film can meet the light detection requirement.

[0054] Figure 3 The surface morphology roughness of the PbSe film with transferred single-layer graphene prepared in Example 1 and the PbSe film prepared in Comparative Example 1 is characterized. From the data in the figure, it can be seen that the surface roughness of the PbSe grown on the silicon dioxide substrate with transferred graphene is about 5.87nm ( Figure 3 a in the figure), while the surface roughness of PbSe grown directly on the SiO2 surface is about 36.58nm ( Figure 3 b), which shows that forming a graphene layer on a silicon or silicon dioxide substrate first and then growing a PbSe film on the graphene layer can help reduce the surface roughness of PbSe.

[0055] Figure 4 The PbSe film of the transferred single-layer graphene prepared in Example 1 ( Figure 4 Selected area electron diffraction characterization of the PbSe film prepared in Example a) and Comparative Example 1 ( Figure 4 (b) It can be observed that compared with the PbSe grown directly on the silica substrate, no regular sites can be found, while the PbSe grown on the transferred graphene-silicon-silicon dioxide can find obvious (200) crystal plane sites, confirming the crystal orientation of PbSe growth in the region.

[0056] Figure 5 The x-ray diffraction patterns of the PbSe film of the transferred single-layer graphene prepared in Example 1 and the PbSe film prepared in Comparative Example 1 show that the half-peak width of 0.176° indicates that the quality of the PbSe crystals grown on the silicon dioxide substrate of the transferred graphene is much higher than that of the PbSe grown directly on silicon dioxide. This shows that the single crystal quality of the entire PbSe film has reached a relatively high level.

[0057] Figure 6 The mid-wave infrared detection performance of the PbSe film of transferred single-layer graphene prepared in Example 1 is characterized. From the characterization results, it can be seen that the PbSe device on silicon can still achieve a photoelectric response of microamperes under microwatt-level optical power conditions, demonstrating its reliability in the field of infrared photoelectric detection.

[0058] Example 2 This embodiment provides a method for preparing a PbSe single crystal thin film by transferring a double-layer graphene on a silicon substrate to achieve self-assembly growth, which specifically includes the following steps: (1) Transferring double-layer graphene.

[0059] Prepare a double-layer graphene on copper foil and evenly coat a layer of PMMA (polymethyl methacrylate) on its surface. You can use a rotating table to set the speed to 600r / min and rotate for 1 minute to make it more uniform. Then place the copper foil with PMMA spin-coated on the heating table and set the heating table temperature to 100℃ for 30 minutes to solidify the PMMA.

[0060] Take KOH powder and deionized water in a mass ratio of 1:5 to prepare a 20% KOH solution, and immerse the copper foil with PMMA in the KOH solution. After 2 hours, PMMA will carry a single-layer graphene film and float on the surface of the KOH solution.

[0061] Take a clean silica substrate and pick up the PMMA. PMMA will carry a single-layer graphene film attached to the silicon substrate; rinse with deionized water and dry on a heating table at 60°C, then soak the silica substrate with PMMA in acetone solution for 2 hours, rinse with water and blow dry to form a graphene / silicon substrate, that is, obtain a silica substrate with a double-layer graphene transferred.

[0062] (2) Growth of PbSe thin film.

[0063] The specific steps are the same as those in Example 1.

[0064] The test results of the PbSe film with transferred double-layer graphene prepared in Example 2 are as follows: like Figure 7The figure shows a PbSe film with transferred double-layer graphene. It can be seen from the figure that the surface density of the PbSe film grown after transferring double-layer graphene on the silicon dioxide surface prepared in Example 2 is comparable to that of the PbSe film grown on the single-layer graphene prepared in Example 1. Figure 8 The X-ray diffraction pattern of the PbSe film with transferred double-layer graphene prepared in Example 2 has a half-peak width of about 0.181°. It can be judged that the quality of the PbSe crystals grown on the silicon dioxide substrate with transferred double-layer graphene is still reliable, indicating that this method is also applicable to the silicon substrate with transferred double-layer graphene.

[0065] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A silicon-based PbSe single crystal thin film, characterized in that: It comprises a substrate, a graphene layer arranged on the substrate, and a PbSe thin film layer arranged on the graphene layer, wherein the substrate is a silicon substrate or a silicon dioxide substrate; Wherein, the surface roughness of the silicon-based PbSe single crystal film is 4nm~10nm; The defect density of the silicon-based PbSe single crystal film is 0.8 nm -2 ~1.2nm -2 ; The half-peak width of the silicon-based PbSe single crystal film is 0.15°~0.2°.

2. The silicon-based PbSe single crystal thin film according to claim 1, characterized in that: The silicon-based PbSe single crystal thin film has a (200) crystal plane orientation.

3. The silicon-based PbSe single crystal thin film according to claim 1, characterized in that: The thickness of the graphene layer is 0.3nm~1.2nm.

4. The silicon-based PbSe single crystal thin film according to claim 1, characterized in that: The thickness of the PbSe thin film layer is 80nm~100nm.

5. The silicon-based PbSe single crystal thin film according to claim 1, characterized in that: The silicon crystal plane of the substrate is a (100) plane.

6. The method for preparing a silicon-based PbSe single crystal thin film according to any one of claims 1 to 5, characterized in that: The following steps are involved: Transferring at least one layer of graphene to the surface of a silicon substrate or a silicon dioxide substrate by a wet transfer process, forming a graphene layer on the surface of the silicon substrate or the silicon dioxide substrate, and obtaining a silicon substrate or a silicon dioxide substrate with a graphene layer; PbSe is epitaxially grown on the graphene layer by a chemical vapor deposition method to form a PbSe thin film layer, thereby obtaining a silicon-based PbSe single crystal thin film.

7. The preparation method according to claim 6, characterized in that: The method of transferring at least one layer of graphene to the surface of a silicon substrate or a silicon dioxide substrate by a wet transfer process specifically comprises the following steps: The surface of the single-layer or multi-layer graphene grown on the copper foil is coated with polymethyl methacrylate, and after drying, it is immersed in a KOH solution until the polymethyl methacrylate floats; The floating polymethyl methacrylate is scooped up using a silicon substrate or a silicon dioxide substrate, rinsed with water and then dried, and finally immersed in an acetone solution, rinsed with water and blown dry to form a graphene layer on the surface of the silicon substrate or the silicon dioxide substrate to obtain a silicon substrate or a silicon dioxide substrate with a graphene layer.

8. The preparation method according to claim 7, characterized in that: The mass fraction of the KOH solution is 15% to 25%, and the immersion time in the acetone solution is 1 h to 2 h.

9. The preparation method according to claim 6, characterized in that: The method for epitaxially growing PbSe on the graphene layer specifically comprises the following steps: Along the flow direction of the carrier gas from upstream to downstream, using PbSe powder as an evaporation source material and Se powder as a supplementary source, setting a silicon substrate or a silicon dioxide substrate with a graphene layer, evacuating, first heating, then keeping the temperature, and finally cooling to form a PbSe thin film layer; The heating temperatures of the Se powder and PbSe powder are 250°C to 350°C and 700°C to 750°C respectively, the heating rate is ≤10°C / min, and the time from room temperature to the heating temperature is 70min to 80min; The heating temperature of the silicon substrate or silicon dioxide substrate with the graphene layer is 300° C. to 400° C.; The insulation time is 4min~8min; The vacuum is evacuated to a vacuum degree of 1×10 -3 Pa~1×10 -2 Pa, control the carrier gas flow rate to 10sccm~20sccm; The PbSe powder and Se powder are mixed in a mass ratio of 1-2:2-4.

10. An infrared photoelectric detector, characterized in that: A silicon-based PbSe single crystal thin film comprising any one of claims 1 to 5.

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