Organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector and preparation method thereof

Abstract

The invention discloses an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector and a preparation method thereof, and relates to the technical field of ultraviolet detection. The objective of the invention is to solve the problem that a conventional inorganic material ultraviolet photoelectric detector is difficult to meet the specific requirements of curved surface fitting of wearable equipment. The invention discloses an organic-inorganic type PFO / a-Ga2O3 heterojunction flexible ultraviolet detector. The organic-inorganic type PFO / a-Ga2O3 heterojunction flexible ultraviolet detector comprises a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer and a contact electrode, the organic / inorganic heterojunction structure fully integrates the advantages of an organic material and an inorganic material, photon-generated carriers can be effectively separated through heterojunction, the responsivity of the detector to solar-blind ultraviolet signals can be improved, meanwhile, self-driven low-power-consumption and low-cost preparation is achieved, the requirement for integration of flexible electronic devices is met, and the application prospect is wide. The method has a wide development prospect.

Description

Technical Field

[0001] This invention relates to the field of ultraviolet detection technology, specifically to an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector and its preparation method. Background Technology

[0002] Following laser and infrared detection technologies, ultraviolet (UV) detection technology has gradually developed as an emerging dual-use technology, demonstrating broad application value in several important fields, such as military early warning, biochemical monitoring, and space communication. Wide-bandgap semiconductor UV detectors, due to their advantages of small size, light weight, and the elimination of filters and cooling devices, are considered a highly promising next-generation UV photoelectric detection device. In recent years, with the rapid development of science and technology, high-efficiency and energy-saving UV detectors with special functions suitable for complex environments have gradually become a research hotspot in the field of photoelectric detection. Among them, self-driven UV detectors that can operate without external bias voltage are a typical example. Compared with traditional photoelectric detectors, the self-driven structure eliminates the power supply section, thereby significantly reducing device size, lowering power consumption, and improving integration flexibility.

[0003] Traditional inorganic ultraviolet photodetectors have the advantage of stability, but their high-temperature processing and rigid substrates limit their application in flexible integration, making it difficult to meet the specific requirements of curved surface bonding in wearable devices. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that traditional inorganic material ultraviolet photodetectors cannot meet the specific requirements of curved surface fitting in wearable devices, and to provide an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector and its preparation method.

[0005] An organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector includes a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer, and a contact electrode;

[0006] The flexible substrate is provided with an a-Ga2O3 thin film layer, which completely covers the flexible substrate; a PFO thin film layer is provided on the a-Ga2O3 thin film layer, which partially covers the a-Ga2O3 thin film layer.

[0007] Contact electrodes are respectively provided on the a-Ga2O3 thin film layer and the PFO thin film layer.

[0008] A method for fabricating an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector is specifically carried out according to the following steps:

[0009] 1. Preparation of α-Ga2O3 thin film layer on the surface of flexible substrate;

[0010] II. A PFO thin film layer is prepared on a portion of the surface of the a-Ga2O3 thin film layer, and the a-Ga2O3 thin film layer and the PFO thin film layer form a PFO / a-Ga2O3 heterojunction.

[0011] III. Contact electrodes were fabricated on a-Ga2O3 thin film and PFO thin film to obtain an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector.

[0012] The principle of this invention:

[0013] Amorphous gallium oxide (a-Ga₂O₃), with its wide bandgap of approximately 4.9 eV, is a natural material for solar-blind ultraviolet detection. Its cryogenic sputtering process is compatible with large-area flexible substrates (such as PET), and its performance degrades only slightly after repeated bending, opening a new path for the development of flexible ultraviolet electronics. Poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) possesses solution spin-coating properties and is highly compatible with the cryogenic sputtering process of a-Ga₂O₃, enabling interface molecular-level coupling at low temperatures. Its wide bandgap of approximately 3.3 eV facilitates the formation of heterojunctions with a-Ga₂O₃, promoting efficient separation of photogenerated carriers and thus improving device response performance. Regarding defect manipulation, the carbon chain structure of PFO can passivate oxygen defects on the a-Ga₂O₃ surface. Combined with in-situ oxygen doping technology, this further suppresses dark current, improves the photocurrent-to-dark-current ratio, and maintains high responsivity. Furthermore, PFO endows the device with excellent mechanical toughness, enabling bendable detection on flexible PET substrates, laying a technological foundation for the construction of future wearable ultraviolet monitoring systems. The organic / inorganic heterostructure employed in this invention fully integrates the advantages of both organic and inorganic materials, effectively separating photogenerated carriers through the heterojunction, which helps improve the detector's responsivity to solar-blind ultraviolet signals. Simultaneously, it achieves self-driven, low-power, and low-cost fabrication, meeting the requirements for flexible electronic device integration.

[0014] The beneficial effects of this invention are:

[0015] I. The process of this invention is highly controllable, easy to operate, and has low manufacturing cost;

[0016] II. The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared by this invention fully integrates the advantages of organic and inorganic materials. The process is simple and can effectively reduce costs. Low-temperature preparation can improve heterojunction interface defects, and it has good carrier modulation characteristics, responsivity and stability, as well as self-powered characteristics, exhibiting excellent ultraviolet detection performance. The entire thin-film heterojunction device has a simple manufacturing process, is flexible, and has broad development prospects. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of the present invention;

[0018] Figure 2 The photocurrent of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of this invention under ultraviolet light illumination at a wavelength of 254 nm;

[0019] Figure 3 The time response characteristic curve of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of the present invention;

[0020] Figure 4 The image shows the spectral response characteristics of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of this invention. Detailed Implementation

[0021] Specific Implementation Method 1: This implementation method is an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector, including a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer, and a contact electrode;

[0022] The flexible substrate is provided with an a-Ga2O3 thin film layer, which completely covers the flexible substrate; a PFO thin film layer is provided on the a-Ga2O3 thin film layer, which partially covers the a-Ga2O3 thin film layer.

[0023] Contact electrodes are respectively provided on the a-Ga2O3 thin film layer and the PFO thin film layer.

[0024] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the flexible substrate is a PET substrate. All other steps are the same as in Specific Implementation Method One.

[0025] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that the thickness of the a-Ga2O3 thin film layer is 100~200nm. Other steps are the same as in Specific Implementation Method 1 or 2.

[0026] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the thickness of the PFO thin film layer is 80~240nm. The other steps are the same as in Specific Implementation Methods One to Three.

[0027] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the contact electrode is made of Au. The other steps are the same as in Specific Implementation Methods One to Four.

[0028] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the thickness of the contact electrode is 10-20 nm. The other steps are the same as in Specific Implementation Methods One to Five.

[0029] Specific Implementation Method Seven: This implementation method is a preparation method for an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector, specifically completed according to the following steps:

[0030] 1. Preparation of α-Ga2O3 thin film layer on the surface of flexible substrate;

[0031] II. A PFO thin film layer is prepared on a portion of the surface of the a-Ga2O3 thin film layer, and the a-Ga2O3 thin film layer and the PFO thin film layer form a PFO / a-Ga2O3 heterojunction.

[0032] III. Contact electrodes were fabricated on a-Ga2O3 thin film and PFO thin film to obtain an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector.

[0033] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One through Seven in that it uses radio frequency magnetron sputtering technology to prepare an a-Ga2O3 thin film layer on the surface of a flexible substrate. The other steps are the same as in Specific Implementation Methods One through Seven.

[0034] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One through Eight in that the specific method for preparing an a-Ga2O3 thin film layer on the surface of a flexible substrate using radio frequency magnetron sputtering technology is as follows: At room temperature, using Ga2O3 ceramic as the target material, an a-Ga2O3 thin film layer is prepared on the surface of the flexible substrate under an argon atmosphere, a sputtering power of 50~120W, and a working pressure of 0.05~12Pa. Other steps are the same as in Specific Implementation Methods One through Eight.

[0035] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that the method for preparing the PFO thin film layer on a portion of the α-Ga₂O₃ thin film layer is spin-coating. Specifically, poly(9,9-di-n-octylfluorenyl-2,7-diyl) is dissolved in chlorobenzene to obtain a PFO solution with a concentration of 10 mg / mL. The 10 mg / mL PFO solution is then spin-coated onto a portion of the α-Ga₂O₃ thin film layer using a dynamic drop-coating method. After standing for 5-10 minutes, the film is annealed on a hot plate at 120°C for 10-30 minutes, and finally slowly cooled to room temperature to obtain the PFO thin film layer. Other steps are the same as in Specific Implementation Methods One to Nine.

[0036] The beneficial effects of the present invention are verified using the following embodiments:

[0037] Example 1: Combination Figure 1 This embodiment describes an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector, which includes a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer, and a contact electrode.

[0038] The flexible substrate is provided with an a-Ga2O3 thin film layer, which completely covers the flexible substrate; a PFO thin film layer is provided on the a-Ga2O3 thin film layer, which partially covers the a-Ga2O3 thin film layer.

[0039] Contact electrodes are respectively provided on the a-Ga2O3 thin film layer and the PFO thin film layer;

[0040] The flexible substrate is a PET substrate;

[0041] The thickness of the a-Ga2O3 thin film is 100 nm;

[0042] The thickness of the PFO thin film layer is 80 nm;

[0043] The contact electrode is made of Au;

[0044] The thickness of the contact electrode is 20 nm;

[0045] The method for fabricating the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector is specifically carried out according to the following steps:

[0046] I. Preparation of a-Ga2O3 thin film layer on the surface of flexible substrate using radio frequency magnetron sputtering technology;

[0047] The specific method of the radio frequency magnetron sputtering technology described in step one is as follows: at room temperature, using Ga2O3 ceramic (purity is 99.99%) as the target material, under an argon atmosphere, sputtering power of 100W, working pressure of 0.5Pa, and back-floor vacuum pressure of less than 1×10⁻⁶. -4 A 100 nm thick a-Ga2O3 thin film layer was obtained by sputtering on the surface of a flexible substrate for 60 min under the conditions of Pa and substrate temperature at room temperature; the flexible substrate was a PET substrate.

[0048] 2. After partially blocking the surface of the a-Ga2O3 thin film, a PFO thin film is prepared on the unblocked part of the a-Ga2O3 thin film, and the a-Ga2O3 thin film and the PFO thin film form a PFO / a-Ga2O3 heterojunction.

[0049] In step two, the method for preparing the PFO film layer on the unmasked portion of the α-Ga₂O₃ film layer is spin coating. Specifically, poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) is dissolved in chlorobenzene to obtain a PFO solution with a concentration of 10 mg / mL. The 10 mg / mL PFO solution is then spin-coated onto the unmasked portion of the α-Ga₂O₃ film layer using a dynamic drop-coating method. Specifically, a two-step rotation speed program is set: first, a low speed of 500 rpm for 10 seconds to promote initial solution spreading; then, a high speed of 3000 rpm for 60 seconds to achieve uniform film coverage; after standing at room temperature for 5 minutes, the film is annealed on a hot plate at 120°C for 20 minutes, and finally slowly cooled to room temperature to obtain a PFO film layer with a thickness of 80 nm.

[0050] The poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) mentioned in step two was purchased from Aladdin Biochemical Technology Co., Ltd.

[0051] The surface area ratio of the a-Ga2O3 thin film layer to the PFO thin film layer in step two is 2:1;

[0052] 3. Using a mask and magnetron sputtering, an Au film is deposited on the a-Ga2O3 thin film and the PFO thin film. Then, it is annealed for 5 minutes in an argon atmosphere at an annealing temperature of 300℃ to obtain a contact electrode, which is used as a measurement electrode. This completes the fabrication of the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector.

[0053] The contact electrode mentioned in step three has a diameter of 1.2 mm and a thickness of 20 nm.

[0054] Figure 2 The photocurrent of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of this invention under ultraviolet light illumination at a wavelength of 254 nm;

[0055] from Figure 2 As can be seen, the PFO / a-Ga2O3 heterojunction can produce a photoresponse to 254nm light; the detector's response peak is around 250nm, exhibiting good solar-blind ultraviolet detection performance.

[0056] The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 was subjected to dark-state IV characteristic curve testing (dark current) and photocurrent testing under 254nm illumination. (See attached figures.) Figure 3 As shown;

[0057] Figure 3The time response characteristic curve of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of the present invention;

[0058] Depend on Figure 3 It can be seen that the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 has good rectification characteristics and low dark current. Under a bias voltage of 10V, the current increases rapidly in the dark and after irradiation with 254nm ultraviolet light, indicating that the device has a good response to 254nm ultraviolet light.

[0059] The It curve of the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 was measured under 254nm ultraviolet light with a 0V bias voltage by continuously turning the light on and off. Figure 4 As shown;

[0060] Figure 4 The spectral response characteristics of an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 of this invention are shown.

[0061] from Figure 4 It can be seen that the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector prepared in Example 1 has the characteristic of self-powering under 0V bias voltage. Multiple cycles were repeated in this example, and the device exhibits good repeatability. After irradiation with 254nm ultraviolet light, the current of the device increases rapidly.

[0062] Example 2: An organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector, comprising a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer, and a contact electrode;

[0063] The flexible substrate is provided with an a-Ga2O3 thin film layer, which completely covers the flexible substrate; a PFO thin film layer is provided on the a-Ga2O3 thin film layer, which partially covers the a-Ga2O3 thin film layer.

[0064] Contact electrodes are respectively provided on the a-Ga2O3 thin film layer and the PFO thin film layer;

[0065] The flexible substrate is a PET substrate;

[0066] The thickness of the a-Ga2O3 thin film is 150 nm;

[0067] The thickness of the PFO thin film layer is 160 nm;

[0068] The contact electrode is made of Au;

[0069] The thickness of the contact electrode is 20 nm;

[0070] The method for fabricating the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector is specifically carried out according to the following steps:

[0071] I. Preparation of a-Ga2O3 thin film layer on the surface of flexible substrate using radio frequency magnetron sputtering technology;

[0072] The specific method of the radio frequency magnetron sputtering technology described in step one is as follows: at room temperature, using Ga2O3 ceramic (purity is 99.99%) as the target material, under an argon atmosphere, sputtering power of 120W, working pressure of 1Pa, and back-floor vacuum pressure of less than 1×10⁻⁶. - 4 A 150 nm thick a-Ga2O3 thin film layer was obtained by sputtering on the surface of a flexible substrate for 90 min under the conditions of Pa and substrate temperature at room temperature; the flexible substrate was a PET substrate.

[0073] 2. After partially blocking the surface of the a-Ga2O3 thin film, a PFO thin film is prepared on the unblocked part of the a-Ga2O3 thin film, and the a-Ga2O3 thin film and the PFO thin film form a PFO / a-Ga2O3 heterojunction.

[0074] In step two, the method for preparing the PFO film layer on the unmasked portion of the α-Ga₂O₃ film layer is spin coating. Specifically, poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) is dissolved in chlorobenzene to obtain a PFO solution with a concentration of 10 mg / mL. The 10 mg / mL PFO solution is then spin-coated onto the unmasked portion of the α-Ga₂O₃ film layer using a dynamic drop-coating method. Specifically, a two-step rotation speed program is set: first, a low speed of 500 rpm for 10 seconds to promote initial spreading of the solution; then, a high speed of 3000 rpm for 60 seconds to achieve uniform film coverage; after standing at room temperature for 5 minutes, the film is annealed on a hot plate at 120°C for 20 minutes, and finally slowly cooled to room temperature. This process is repeated once to obtain a PFO film layer with a thickness of 160 nm.

[0075] The poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) mentioned in step two was purchased from Aladdin Biochemical Technology Co., Ltd.

[0076] The surface area ratio of the a-Ga2O3 thin film layer to the PFO thin film layer in step two is 2:1;

[0077] 3. Using a mask and magnetron sputtering, an Au film is deposited on the a-Ga2O3 thin film and the PFO thin film. Then, it is annealed for 5 minutes in an argon atmosphere at an annealing temperature of 300℃ to obtain a contact electrode, which is used as a measurement electrode. This completes the fabrication of the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector.

[0078] The contact electrode mentioned in step three has a diameter of 1.2 mm and a thickness of 20 nm.

[0079] Example 3: An organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector, comprising a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer, and a contact electrode;

[0080] The flexible substrate is provided with an a-Ga2O3 thin film layer, which completely covers the flexible substrate; a PFO thin film layer is provided on the a-Ga2O3 thin film layer, which partially covers the a-Ga2O3 thin film layer.

[0081] Contact electrodes are respectively provided on the a-Ga2O3 thin film layer and the PFO thin film layer;

[0082] The flexible substrate is a PET substrate;

[0083] The thickness of the a-Ga2O3 thin film is 200 nm;

[0084] The thickness of the PFO thin film layer is 240 nm;

[0085] The contact electrode is made of Au;

[0086] The thickness of the contact electrode is 20 nm;

[0087] The method for fabricating the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector is specifically carried out according to the following steps:

[0088] I. Preparation of a-Ga2O3 thin film layer on the surface of flexible substrate using radio frequency magnetron sputtering technology;

[0089] The specific method of the radio frequency magnetron sputtering technology described in step one is as follows: at room temperature, using Ga2O3 ceramic (purity is 99.99%) as the target material, under an argon atmosphere, sputtering power of 120W, working pressure of 0.5Pa, and back-floor vacuum pressure of less than 1×10⁻⁶. -4 A 200 nm thick a-Ga2O3 thin film layer was obtained by sputtering on the surface of a flexible substrate for 120 min under the conditions of Pa and substrate temperature at room temperature; the flexible substrate was a PET substrate.

[0090] 2. After partially blocking the surface of the a-Ga2O3 thin film, a PFO thin film is prepared on the unblocked part of the a-Ga2O3 thin film, and the a-Ga2O3 thin film and the PFO thin film form a PFO / a-Ga2O3 heterojunction.

[0091] In step two, the method for preparing the PFO film layer on the unmasked portion of the α-Ga₂O₃ film layer is spin coating. Specifically, poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) is dissolved in chlorobenzene to obtain a PFO solution with a concentration of 10 mg / mL. The 10 mg / mL PFO solution is then spin-coated onto the unmasked portion of the α-Ga₂O₃ film layer using a dynamic drop-coating method. Specifically, a two-step rotation speed program is set: first, a low speed of 500 rpm for 10 seconds to promote initial spreading of the solution; then, a high speed of 3000 rpm for 60 seconds to achieve uniform film coverage; after standing at room temperature for 5 minutes, it is annealed on a hot plate at 120°C for 20 minutes, and finally slowly cooled to room temperature. This process is repeated twice to obtain a PFO film layer with a thickness of 240 nm.

[0092] The poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) mentioned in step two was purchased from Aladdin Biochemical Technology Co., Ltd.

[0093] The surface area ratio of the a-Ga2O3 thin film layer to the PFO thin film layer in step two is 2:1;

[0094] 3. Using a mask and magnetron sputtering, an Au film is deposited on the a-Ga2O3 thin film and the PFO thin film. Then, it is annealed for 5 minutes in an argon atmosphere at an annealing temperature of 300℃ to obtain a contact electrode, which is used as a measurement electrode. This completes the fabrication of the organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector.

[0095] The contact electrode mentioned in step three has a diameter of 1.2 mm and a thickness of 20 nm.

Claims

1. An organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector, characterized in that... The ultraviolet detector includes a flexible substrate, an a-Ga2O3 thin film layer, a PFO thin film layer, and a contact electrode; The flexible substrate is provided with an a-Ga2O3 thin film layer, which completely covers the flexible substrate; a PFO thin film layer is provided on the a-Ga2O3 thin film layer, which partially covers the a-Ga2O3 thin film layer. Contact electrodes are respectively provided on the a-Ga2O3 thin film layer and the PFO thin film layer.

2. The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 1, characterized in that... The flexible substrate is a PET substrate.

3. The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 1, characterized in that... The thickness of the a-Ga2O3 thin film is 100~200nm.

4. The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 1, characterized in that... The thickness of the PFO thin film layer is 80~240nm.

5. The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 1, characterized in that... The contact electrode is made of Au.

6. The organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 1, characterized in that... The thickness of the contact electrode is 10~20nm.

7. The method for fabricating an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector as described in claim 1, characterized in that... The preparation method is specifically carried out according to the following steps:

1. Preparation of α-Ga2O3 thin film layer on the surface of flexible substrate; II. A PFO thin film layer is prepared on a portion of the surface of the a-Ga2O3 thin film layer, and the a-Ga2O3 thin film layer and the PFO thin film layer form a PFO / a-Ga2O3 heterojunction. III. Contact electrodes were fabricated on a-Ga2O3 thin film and PFO thin film to obtain an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector.

8. The method for fabricating an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 7, characterized in that... A-Ga2O3 thin film layer was prepared on the surface of a flexible substrate using radio frequency magnetron sputtering technology.

9. The method for fabricating an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 8, characterized in that... The specific method for preparing an a-Ga2O3 thin film layer on the surface of a flexible substrate using radio frequency magnetron sputtering technology is as follows: at room temperature, using Ga2O3 ceramic as the target material, an a-Ga2O3 thin film layer is prepared on the surface of the flexible substrate under argon atmosphere, sputtering power of 50~120W and working pressure of 0.05~12Pa.

10. The method for preparing an organic-inorganic PFO / a-Ga2O3 heterojunction flexible ultraviolet detector according to claim 7, characterized in that... The method for preparing a PFO thin film on a portion of the surface of an α-Ga₂O₃ thin film is spin coating. Specifically, poly(9,9-di-n-octylfluorenyl-2,7-diyl) is dissolved in chlorobenzene to obtain a PFO solution with a concentration of 10 mg / mL. The 10 mg / mL PFO solution is spin-coated onto a portion of the surface of the α-Ga₂O₃ thin film using a dynamic drop-coating method. After standing for 5-10 min, the film is annealed on a hot plate at 120°C for 10-30 min. Finally, it is slowly cooled to room temperature to obtain the PFO thin film.

Images