Preparation of a 10.6 mu m flexible photoelectric detector based on a novel Ta2PtSe7 alloy

Abstract

The present application relates to the technical field of flexible optoelectronic devices, and particularly relates to a preparation of a 10.6 mu m flexible optoelectronic detector based on a novel Ta2PtSe7 alloy, wherein high-purity Ta2PtSe7 single crystals are prepared from tantalum, platinum and selenium, and then transferred to a flexible substrate by mechanical exfoliation with polydimethylsiloxane film as an intermediate carrier, and then spin-coated with photoresist, laser direct writing and exposure development to obtain a brand-new flexible wearable optoelectronic detector, which has a significantly expanded wavelength range and can reach 10.6 mu m; and due to the special structure of Ta2PtSe7, the optoelectronic detector has good response speed and responsivity, ultrahigh air stability and good flexibility and fatigue resistance, and has great application potential in the field of mid-infrared detection, and compared with the prior art, has a wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of flexible optoelectronic device technology, and in particular to the fabrication of a 10.6μm flexible photodetector based on a novel Ta2PtSe7 alloy. Background Technology

[0002] A photodetector is a device that converts light signals into electrical signals. Its working principle is based on the photoelectric effect, whereby when light shines on a material's surface, the material absorbs the light energy and converts it into electrical energy. With the continuous advancement of modern technology, photodetectors are widely used in communications, medicine, military, and scientific research, such as optical signal reception in fiber optic communication systems, optical imaging, lidar, infrared detection, spectral analysis, and quantum information. Infrared detectors are particularly important in these applications because they can detect radiation in the invisible light band and are widely used in thermal imaging, night vision devices, and gas analysis. Traditional infrared detectors rely on materials such as silicon, gallium arsenide, and indium gallium, but these materials have limited photoelectric response within specific wavelength ranges and lack flexibility, limiting their application in wearable devices, smart sensors, and integrated systems.

[0003] With the deepening research into novel materials, two-dimensional materials have become a hot topic in photodetector research due to their unique electronic structure and excellent photoelectric properties. Two-dimensional materials are a class of layered materials with atomic-level thickness, where electrons can only move freely in two dimensions, while the third dimension is affected by quantum confinement effects. These materials exhibit broad application potential in multiple fields due to their unique physical, chemical, and optical properties. These novel materials not only demonstrate advantages in light absorption and carrier mobility but also hold great potential in the design and fabrication of flexible photodetectors.

[0004] Traditional photodetectors are typically made of rigid materials, which makes it difficult to meet the demands of emerging applications such as wearable devices, flexible electronics, and smart sensors for flexibility and efficient energy conversion. With the increasing demand for flexible electronic devices, the development of novel flexible photodetectors has become a research hotspot.

[0005] In the prior art, patent document CN114203915A discloses a flexible organic photodetector based on a thin-layer metal electrode and its preparation method. The flexible organic photodetector includes a flexible substrate, a thin-layer metal anode, a hole extraction layer, a hole transport layer, a photosensitive layer, an electron transport layer, and a metal cathode arranged sequentially. The flexible organic photodetector prepared in this invention has the advantages of good stability and low power consumption, but the detection range of the flexible photodetector still needs to be improved.

[0006] Therefore, based on the relevant technologies mentioned above, there is an urgent need to develop a fabrication method for a 10.6μm flexible photodetector based on a novel Ta2PtSe7 alloy. Summary of the Invention

[0007] In view of this, the purpose of this invention is to propose a method for fabricating a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, so as to solve the problems of small detection range and poor stability of existing flexible photodetectors.

[0008] To achieve the above objectives, this invention provides a method for fabricating a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy.

[0009] The fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy includes the following steps:

[0010] Step A1. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press the film to ensure full contact between the polydimethylsiloxane film and the Ta2PtSe7 crystal flakes. After 6-9 minutes, separate the polydimethylsiloxane film from the tape. Then, apply the polydimethylsiloxane film to a flexible substrate and apply pressure to the surface of the polydimethylsiloxane film. After 4-7 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0011] Step A2. Spin-coating photoresist onto the Ta2PtSe7 single crystal thin film using a spin coater, followed by laser direct writing, exposure and development to obtain a Ta2PtSe7 sample covered with electrode patterns. Then, depositing a titanium-gold composite thin film at the patterned locations using electron beam evaporation, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0012] Preferably, the method for preparing the Ta2PtSe7 single crystal in step A1 is as follows:

[0013] Step B1. Weigh out tantalum, platinum and selenium separately, mix them evenly, grind them in a mortar for 5-10 minutes, and then press them into tablets using a tableting mold with a diameter of 10 mm to obtain substance A;

[0014] Step B2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to V1 using a mechanical pump and a molecular pump assembly. Then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to T1. After the quartz tube cools down, place it in a muffle furnace, set the temperature to T2, and hold it at that temperature for 28-30 days to obtain Ta2PtSe7 single crystal.

[0015] Preferably, the molar ratio of tantalum, platinum and selenium in step B1 is 2:1:7;

[0016] The pressure during tableting is 58-65 MPa, and the tableting time is 35-40 seconds.

[0017] Preferably, V1 < 10 in step B2 -5 Torr;

[0018] The temperature T1 is 1880-1930℃;

[0019] The temperature T2 is 700-740℃.

[0020] Preferably, the flexible substrate in step A1 is polyethylene terephthalate.

[0021] Preferably, in step A2, the titanium layer in the titanium-gold composite film has a thickness of 8-12 nm and the gold layer has a thickness of 65-73 nm.

[0022] The beneficial effects of this invention are:

[0023] This invention provides a method for fabricating a 10.6 μm flexible photodetector based on a novel Ta₂PtSe₇ alloy. The method involves uniformly mixing tantalum, platinum, and selenium in a specific molar ratio, pressing the mixture into a sheet, and then heating it in a quartz tube to obtain a high-purity and high-crystallinity Ta₂PtSe₇ single crystal. After mechanical exfoliation, the Ta₂PtSe₇ single crystal is transferred to a flexible substrate using a polydimethylsiloxane film as an intermediate carrier. Following spin-coating with photoresist, laser direct writing, and exposure and development, a novel flexible wearable photodetector is obtained, with a significantly extended operating wavelength range reaching 10.6 μm. Furthermore, the unique structure of Ta₂PtSe₇ results in excellent response speed and responsivity, extremely high air stability, and good flexibility and fatigue resistance, making the flexible photodetector prepared in this invention highly promising for applications in the mid-infrared detection field. Compared with existing technologies, it has broad application prospects. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this 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 for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the Ta2PtSe7 single crystal prepared in Example 1 of the present invention;

[0026] Figure 2 This is an X-ray scan of the Ta2PtSe7 single crystal prepared in Example 1 of this invention;

[0027] Figure 3 This is a scanning electron microscope image of the Ta2PtSe7 single crystal prepared in Example 1 of this invention;

[0028] Figure 4 This is a point scan energy spectrum of the Ta2PtSe7 single crystal prepared in Example 1 of this invention;

[0029] Figure 5 The above is a surface scan energy spectrum of the Ta2PtSe7 single crystal prepared in Example 1 of this invention;

[0030] Figure 6 This is a schematic diagram of the Ta2PtSe7 single crystal obtained in Example 1 of the present invention after mechanical exfoliation;

[0031] Figure 7 This is a schematic diagram of the Ta2PtSe7 flexible device prepared in Example 1 of the present invention;

[0032] Figure 8 The image shows the photoelectric performance of the Ta2PtSe7 flexible device prepared in Example 1 of this invention.

[0033] Figure 9 This is a comparison of the Raman spectra of the Ta2PtSe7 single crystal prepared in Example 1 of the present invention before and after being placed in air for one year;

[0034] Figure 10 The image shows a flexible test pattern of the Ta2PtSe7 flexible device prepared in Example 1 of this invention. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0036] The sources and properties of some of the raw materials used in this invention are as follows:

[0037] Elemental tantalum was purchased from Dongguan Junheng Metal Materials Co., Ltd.; elemental platinum was purchased from Shanghai Yinli Metal Materials Co., Ltd.; elemental selenium was purchased from Sichuan Gaochun Materials Technology Co., Ltd.; polydimethylsiloxane was purchased from Hubei Dahao Chemical Co., Ltd.; and polyethylene terephthalate was purchased from Hubei Dahao Chemical Co., Ltd.

[0038] Example 1: Fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, comprising the following steps:

[0039] S1. Weigh out 0.326g of tantalum, 0.175g of platinum, and 0.500g of selenium (the molar ratio of tantalum, platinum, and selenium is 2:1:7), mix them thoroughly, grind them in a mortar for 5 minutes, and then use a tableting mold with a diameter of 10mm to compress the tablets. Set the pressure during tableting to 58MPa and the tableting time to 35s to obtain substance A.

[0040] S2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to 9 × 10⁻⁶ using a mechanical pump and a molecular pump assembly. -6 Torr, then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to 1880℃. After the quartz tube cools down, place it in a muffle furnace, set the temperature to 700℃ and hold it for 28-30 days to obtain Ta2PtSe7 single crystal.

[0041] S3. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press the film to ensure full contact between the polydimethylsiloxane film and the Ta2PtSe7 crystal flakes. After 6 minutes, separate the polydimethylsiloxane film from the tape. Then, apply the polydimethylsiloxane film to a flexible polyethylene terephthalate substrate and apply pressure to the surface of the polydimethylsiloxane film. After 4 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0042] S4. A Ta2PtSe7 single crystal thin film is spin-coated with photoresist using a spin coater, and then laser-written, exposed and developed to obtain a Ta2PtSe7 sample covered with electrode patterns. A titanium-gold composite thin film is then deposited at the patterned locations using electron beam evaporation, wherein the titanium layer thickness is 8nm and the gold layer thickness is 65nm, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0043] Example 2: Fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, comprising the following steps:

[0044] S1. Weigh out 0.326g of tantalum, 0.175g of platinum, and 0.500g of selenium (the molar ratio of tantalum, platinum, and selenium is 2:1:7), mix them thoroughly, grind them in a mortar for 6 minutes, and then use a tableting mold with a diameter of 10mm to compress the tablets. Set the pressure during tableting to 59MPa and the tableting time to 36s to obtain substance A.

[0045] S2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to 9 × 10⁻⁶ using a mechanical pump and a molecular pump assembly. -6Torr, then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to 1890℃. After the quartz tube cools down, place it in a muffle furnace, set the temperature to 710℃ and hold it for 28 days to obtain Ta2PtSe7 single crystal.

[0046] S3. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press the film to ensure full contact between the polydimethylsiloxane film and the Ta2PtSe7 crystal flakes. After 7 minutes, separate the polydimethylsiloxane film from the tape. Then, apply the polydimethylsiloxane film to a flexible polyethylene terephthalate substrate and apply pressure to the surface of the polydimethylsiloxane film. After 5 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0047] S4. A Ta2PtSe7 single crystal thin film is spin-coated with photoresist using a spin coater, and then laser-written, exposed and developed to obtain a Ta2PtSe7 sample covered with electrode patterns. A titanium-gold composite thin film is then deposited at the patterned locations using electron beam evaporation, wherein the titanium layer thickness is 9nm and the gold layer thickness is 66nm, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0048] Example 3: Fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, comprising the following steps:

[0049] S1. Weigh out 0.326g of tantalum, 0.175g of platinum, and 0.500g of selenium (the molar ratio of tantalum, platinum, and selenium is 2:1:7), mix them thoroughly, grind them in a mortar for 7 minutes, and then use a tableting mold with a diameter of 10mm to compress the tablets. Set the pressure during tableting to 60MPa and the tableting time to 37s to obtain substance A.

[0050] S2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to 9 × 10⁻⁶ using a mechanical pump and a molecular pump assembly. -6 Torr, then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to 1900℃. After the quartz tube cools down, place it in a muffle furnace, set the temperature to 720℃ and hold it for 29 days to obtain Ta2PtSe7 single crystal.

[0051] S3. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press the film to ensure full contact between the polydimethylsiloxane film and the Ta2PtSe7 crystal flakes. After 7 minutes, separate the polydimethylsiloxane film from the tape. Then, apply the polydimethylsiloxane film to a flexible polyethylene terephthalate substrate and apply pressure to the surface of the polydimethylsiloxane film. After 5 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0052] S4. A Ta2PtSe7 single crystal thin film is spin-coated with photoresist using a spin coater, and then laser-written, exposed and developed to obtain a Ta2PtSe7 sample covered with electrode patterns. Then, a titanium-gold composite thin film is deposited at the patterned position using electron beam evaporation, wherein the titanium layer thickness is 9nm and the gold layer thickness is 67nm, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0053] Example 4: Fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, comprising the following steps:

[0054] S1. Weigh out 0.326g of tantalum, 0.175g of platinum, and 0.500g of selenium (the molar ratio of tantalum, platinum, and selenium is 2:1:7), mix them thoroughly, grind them in a mortar for 8 minutes, and then use a tableting mold with a diameter of 10mm to compress the tablets. Set the pressure during tableting to 61MPa and the tableting time to 38s to obtain substance A.

[0055] S2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to 9 × 10⁻⁶ using a mechanical pump and a molecular pump assembly. -6 Torr, then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to 1910℃. After the quartz tube cools down, place it in a muffle furnace, set the temperature to 725℃ and hold it for 29 days to obtain Ta2PtSe7 single crystal.

[0056] S3. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press the film to ensure full contact between the polydimethylsiloxane film and the Ta2PtSe7 crystal flakes. After 8 minutes, separate the polydimethylsiloxane film from the tape. Then, apply the polydimethylsiloxane film to a flexible polyethylene terephthalate substrate and apply pressure to the surface of the polydimethylsiloxane film. After 6 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0057] S4. A Ta2PtSe7 single crystal thin film is spin-coated with photoresist using a spin coater, and then laser-written, exposed and developed to obtain a Ta2PtSe7 sample covered with electrode patterns. A titanium-gold composite thin film is then deposited at the patterned locations using electron beam evaporation, wherein the titanium layer thickness is 10nm and the gold layer thickness is 69nm, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0058] Example 5: Fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, comprising the following steps:

[0059] S1. Weigh out 0.326g of tantalum, 0.175g of platinum, and 0.500g of selenium (the molar ratio of tantalum, platinum, and selenium is 2:1:7), mix them thoroughly, grind them in a mortar for 9 minutes, and then use a tableting mold with a diameter of 10mm to compress the tablets. Set the pressure during tableting to 63MPa and the tableting time to 39s to obtain substance A.

[0060] S2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to 9 × 10⁻⁶ using a mechanical pump and a molecular pump assembly. -6 Torr, then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to 1930℃. After the quartz tube cools down, place it in a muffle furnace, set the temperature to 730℃ and hold it for 30 days to obtain Ta2PtSe7 single crystal.

[0061] S3. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press and ensure that the polydimethylsiloxane film is in full contact with the Ta2PtSe7 crystal flakes. After 9 minutes, separate the polydimethylsiloxane film from the tape, then apply the polydimethylsiloxane film to a flexible polyethylene terephthalate substrate and apply pressure to the surface of the polydimethylsiloxane film. After 7 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0062] S4. A Ta2PtSe7 single crystal thin film is spin-coated with photoresist using a spin coater, and then laser-written, exposed and developed to obtain a Ta2PtSe7 sample covered with electrode patterns. A titanium-gold composite thin film is then deposited at the patterned locations using electron beam evaporation, wherein the titanium layer thickness is 11nm and the gold layer thickness is 71nm, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0063] Example 6: Fabrication of a 10.6 μm flexible photodetector based on a novel Ta2PtSe7 alloy, comprising the following steps:

[0064] S1. Weigh out 0.326g of tantalum, 0.175g of platinum, and 0.500g of selenium (the molar ratio of tantalum, platinum, and selenium is 2:1:7), mix them evenly, grind them in a mortar for 10 minutes, and then use a tableting mold with a diameter of 10mm to compress the tablets. Set the pressure during tableting to 65MPa and the tableting time to 40s to obtain substance A.

[0065] S2. Place substance A in a quartz tube with an outer diameter of 13 mm, and reduce the vacuum inside the tube to 9 × 10⁻⁶ using a mechanical pump and a molecular pump assembly. -6 Torr, then seal the quartz tube with a hydrogen-oxygen mixture and set the temperature to 1930℃. After the quartz tube cools down, place it in a muffle furnace, set the temperature to 740℃ and hold it for 30 days to obtain Ta2PtSe7 single crystal.

[0066] S3. After mechanically peeling the Ta2PtSe7 single crystal onto Scotch tape, apply a polydimethylsiloxane film to the area of ​​the tape with more Ta2PtSe7 crystal flakes. Use a cotton swab to press and ensure that the polydimethylsiloxane film is in full contact with the Ta2PtSe7 crystal flakes. After 9 minutes, separate the polydimethylsiloxane film from the tape, then apply the polydimethylsiloxane film to a flexible polyethylene terephthalate substrate and apply pressure to the surface of the polydimethylsiloxane film. After 7 minutes, remove the polydimethylsiloxane film to obtain the Ta2PtSe7 single crystal film.

[0067] S4. A Ta2PtSe7 single crystal thin film is spin-coated with photoresist using a spin coater, and then laser-written, exposed and developed to obtain a Ta2PtSe7 sample covered with electrode patterns. A titanium-gold composite thin film is then deposited at the patterned locations using electron beam evaporation, wherein the titanium layer thickness is 12nm and the gold layer thickness is 73nm, thus obtaining a 10.6μm flexible photodetector based on the novel Ta2PtSe7 alloy.

[0068] Performance testing:

[0069] Ta2PtSe7 Single Crystal Performance Test:

[0070] The Ta2PtSe7 single crystal prepared in this invention was thoroughly ground, and X-ray diffraction analysis was used to obtain the X-ray scan pattern, as shown below. Figure 2As shown in the figure, the upper black curve is the actual spectrum, and the lower blue curve is the theoretical spectrum of Ta2PtSe7 powder. The high degree of overlap between the two curves demonstrates that the Ta2PtSe7 prepared in this invention possesses high purity and high crystallinity. Figure 3 The scanning electron microscope image of the Ta2PtSe7 single crystal shows a distinct layered structure. Figure 4 and Figure 5 The point scan energy dispersive spectroscopy and surface scan energy dispersive spectroscopy of Ta2PtSe7 single crystal proved that the single crystal prepared in this invention has the same element ratio as the required single crystal and the element distribution is uniform.

[0071] Mechanically peeling Ta₂PtSe₇ single crystals onto Scotch tape reveals that the weak van der Waals forces between the layers make them easily dissociable. After attaching a silicon wafer to the sample location on the tape and gently peeling it off, rod-shaped Ta₂PtSe₇ samples with lengths of tens of micrometers can be observed under an optical microscope. Figure 6 It can be seen that the stripped Ta2PtSe7 sample has an atomically smooth and clean surface;

[0072] Photoelectric performance testing of flexible photodetectors:

[0073] The Ta2PtSe7 flexible device prepared in this invention was externally connected to a PCB board using conductive silver paste (SPI 05001-AB) and high-purity gold wire. Electrical tests were performed using an FS-Pro semiconductor analyzer, and its IV curve is shown below. Figure 8 As shown in (a), the source-drain voltage and source-drain current curves exhibit a good linear relationship, indicating the metallic properties and good contact with the metal electrodes during device fabrication; Figure 8 As shown in (b), the Ta2PtSe7 flexible device is aligned with the center of a 10.6 μm carbon dioxide laser spot (laser spot size 3 × 10⁻⁶). -2 cm 2 The size is much larger than the channel area of ​​9×10 -8 cm 2 Using photoelectric gates to switch lasers on and off, and to test photoelectric detection;

[0074] A 0.1V excitation voltage was applied to the source-drain electrodes of the device, and the results of tests on different laser power densities and photocurrents in the 10.6μm band were as follows. Figure 8 As shown in (c), with the increase of laser power density (0.67-2 W / cm²), 2The photocurrent increased from 6 nA to 30 nA; its photocurrent test showed a significant photothermal-electric effect (Seebeck effect). Subsequently, the photoelectric performance of the Ta2PtSe7 flexible device was comprehensively evaluated using lasers from the visible to near-infrared and then to the mid-infrared (671 nm, 1064 nm, 10.6 μm), with response times of 2.9 s, 3.4 s, and 4.6 s, respectively. Figure 8 As shown in (d); the functional relationship between its photocurrent and the power density of the externally excited laser is as follows: Figure 8 As shown in (e), the fitting coefficients (α) are all greater than 1. This is due to the combined effect of multiple factors, including the significance of the carrier temperature gradient, the thermoelectric potential difference, the complexity of carrier transport characteristics, and carrier dynamics under non-equilibrium conditions. Furthermore, its optical responsivity and the power density of the externally excited laser also increase with increasing power. Figure 8 As shown in (f), this is also an important characteristic of the thermoelectric effect;

[0075] Stability test:

[0076] The Ta2PtSe7 prepared in this invention was subjected to Raman spectroscopy testing. After being exposed to air for one year, the Ta2PtSe7 sample showed no significant changes under an optical microscope, and its Raman spectrum remained essentially consistent with the initial value. Figure 9 As shown, the excellent air stability exhibited by Ta2PtSe7 lays a solid foundation for its performance in later applications. In the field of wearable technology, the durability and reliability of devices are key considerations, and this feature of Ta2PtSe7 meets these requirements.

[0077] Flexibility test:

[0078] The Ta2PtSe7 flexible device prepared in this invention can perform simple flexible wearable bending, such as... Figure 10 As shown in (a); the bending test was conducted using a high-precision vernier caliper, and the bending radius was calculated as follows during the bending process. Figure 10 As shown in (b), during repeated bending tests with a radius of 0.2 mm, the Ta2PtSe7 flexible device did not show significant degradation at a photodetector size of 10.6 μm, indicating its good mechanical properties and fatigue resistance.

[0079] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

[0080] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. Preparation of a 10.6 pm flexible photodetector based on a novel Ta2PtSe7 alloy, characterized in that, Comprising the following steps: Step A1. After mechanical exfoliation of Ta2PtSe7 single crystal on Scotch tape, a polydimethylsiloxane film is attached to the position where there are more Ta2PtSe7 crystal flakes on the tape, a cotton swab is used to press to ensure that the polydimethylsiloxane film is in full contact with the Ta2PtSe7 crystal flakes, after 6-9 min, the polydimethylsiloxane film is separated from the tape, then the polydimethylsiloxane film is attached to a flexible substrate, and pressure is applied to the surface of the polydimethylsiloxane film, after 4-7 min, the polydimethylsiloxane film is removed, and a Ta2PtSe7 single crystal thin film is obtained; Step A2. After spin coating photoresist on the Ta2PtSe7 single crystal thin film using a spin coater, and then laser direct writing, exposure and development, a sample of Ta2PtSe7 covered with an electrode pattern is obtained, and a titanium-gold composite film is deposited at the pattern position using electron beam evaporation, thereby obtaining a 10.6 μm flexible photoelectric detector based on the novel Ta2PtSe7 alloy.

2. The preparation of 10.6 pm flexible photodetector based on novel Ta2PtSe7 alloy according to claim 1, characterized in that, The preparation method of the Ta2PtSe7 single crystal in step A1 is as follows: Step B1. Weigh the tantalum, platinum and selenium elements respectively, mix them evenly, grind them in a mortar for 5-10 min, and then use a 10 mm diameter tablet press to press them into tablets to obtain substance A; Step B2. Place substance A in a 13 mm outer diameter quartz tube, reduce the vacuum in the tube to V1 using a mechanical pump and a molecular pump set, seal the quartz tube with hydrogen-oxygen mixed gas, and set the temperature to T1. After the quartz tube cools down, place it in a muffle furnace, set the temperature to T2 and keep it for 28-30 days to obtain Ta2PtSe7 single crystal.

3. The preparation of 10.6 pm flexible photodetector based on novel Ta2PtSe7 alloy according to claim 2, characterized in that, The molar ratio of the tantalum, platinum and selenium elements in step B1 is 2:1:7; The pressure during tabletting is 58-65 MPa, and the tabletting time is 35-40 s.

4. The preparation of 10.6 pm flexible photodetector based on novel Ta2PtSe7 alloy according to claim 2, characterized in that, V1<10 as described in step B2 -5 Torr; The temperature T1 is 1880-1930℃; The temperature T2 is 700-740℃.

5. The preparation of 10.6 pm flexible photodetector based on novel Ta2PtSe7 alloy according to claim 1, characterized in that, The flexible substrate in step A1 is polyethylene terephthalate.

6. The preparation of 10.6 pm flexible photodetector based on novel Ta2PtSe7 alloy according to claim 1, characterized in that, The titanium layer in the titanium-gold composite film in step A2 is 8-12 nm thick, and the gold layer is 65-73 nm thick.

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