AlScN gallium oxide solar-blind detector based on transverse electric field and preparation method thereof

Abstract

The present invention provides an AlScN gallium oxide solar-blind detector based on a transverse electric field and a preparation method thereof, comprising a substrate and at least one AlScN / Ga2O3 heterostructure arranged on the surface of the substrate, wherein each AlScN / Ga2O3 heterostructure comprises an independent gallium oxide block etched on the surface of the substrate, an AlScN layer deposited on one side of the gallium oxide block, a first metal electrode deposited on one side of the gallium oxide block and a second metal electrode deposited on one side of the AlScN layer, and the AlScN layer forms a transverse electric field with the gallium oxide block. The AlScN / Ga2O3 heterostructure with a transverse electric field is used to solve the problem of low light-to-dark current ratio caused by AlScN leakage in a longitudinal electric field, while still maintaining the advantage of high responsiveness of the gallium oxide heterojunction solar-blind detector.

Description

Technical Field

[0001] The invention relates to the field of ferroelectric semiconductors, and in particular to an AlScN gallium oxide solar-blind detector based on a transverse electric field and a preparation method thereof. Background Art

[0002] Solar-blind ultraviolet photodetectors only respond to light in the ultraviolet band of 220-280 nm and are not interfered by light signals of other wavelengths. Therefore, they have the advantages of low background noise and good stability. They are currently widely used in the fields of civil medicine, military defense, etc. Ga2O3 materials have a bandgap width of 4.6-4.9 eV, and their light response band directly corresponds to the ultraviolet band. At the same time, because Ga2O3 materials are direct bandgap semiconductors, they have the advantages of high light absorption rate. In addition, the material also has excellent chemical and thermal stability and can adapt to various harsh environments. Therefore, Ga2O3 materials are widely used in the preparation of solar-blind ultraviolet photodetectors. The currently developed Ga2O3 solar-blind ultraviolet photodetectors require external power drive, so they have the disadvantages of large size, high energy consumption, and difficulty in integration. The Ga2O3 solar-blind ultraviolet photodetectors based on heterojunction structures can use the junction effect to achieve self-driving and can work normally under power-free conditions. In addition, the built-in electric field in the heterojunction structure can promote the separation of photogenerated carriers and improve the detector's responsiveness.

[0003] AlScN materials can use the Sc component to adjust the bandgap width, achieve a bandgap width that perfectly matches the Ga2O3 material (4.6-5.2 eV), reduce the barrier peak at the interface, optimize the heterojunction interface quality, and improve the detector performance. In addition, the wide bandgap of AlScN materials corresponds to the absorption spectrum of ultraviolet light (220-280 nm), which can improve the light absorption rate of the device. At the same time, AlScN materials also have excellent ferroelectric properties, and their polarization electric field can adjust the intensity of the built-in electric field and the width of the depletion region, thereby further promoting the separation of photogenerated carriers and improving the responsiveness of the device. Therefore, AlScN is considered to be an ideal material for preparing Ga2O3 heterojunction high-performance solar-blind ultraviolet photodetectors.

[0004] However, the AlScN materials currently used all apply a vertical electric field to achieve polarization reversal of their longitudinal axis. This longitudinal polarization reversal will cause the formation of non-uniform domains in the AlScN film, thereby increasing leakage in the AlScN film and reducing the light-to-dark current ratio and responsivity of the gallium oxide heterojunction solar-blind detector. At the same time, the longitudinal electric field will directly cause the nucleation of AlScN ferroelectric domains, increase the capture and recombination of photogenerated carriers in traps, shorten their lifetime, and prolong the recovery time of the gallium oxide heterojunction solar-blind detector.

[0005] In summary, the current longitudinal electric field AlScN / Ga2O3 heterojunction solar-blind detector has the problems of easy leakage of AlScN and easy nucleation of ferroelectric domains, which makes it difficult for the responsiveness of the AlScN / Ga2O3 heterojunction solar-blind detector to maintain excellent performance for a long time. Summary of the invention

[0006] The purpose of the present invention is to provide an AlScN gallium oxide solar-blind detector based on a transverse electric field and a preparation method thereof, which adopts an AlScN / Ga2O3 heterostructure with a transverse electric field to solve the problem of low light-to-dark current ratio caused by AlScN leakage with a longitudinal electric field, while still maintaining the advantage of high responsiveness of the gallium oxide heterojunction solar-blind detector.

[0007] To achieve the above objectives, in the first aspect, the present technical solution provides an AlScN gallium oxide solar-blind detector based on a transverse electric field, comprising: a substrate and at least one AlScN / Ga2O3 heterostructure arranged on the surface of the substrate, wherein each AlScN / Ga2O3 heterostructure comprises an independent gallium oxide block etched on the surface of the substrate, an AlScN layer deposited on one side of the gallium oxide block, a first metal electrode deposited on one side of the gallium oxide block, and a second metal electrode deposited on one side of the AlScN layer, and the AlScN layer forms a transverse electric field with the gallium oxide block.

[0008] The AlScN / Ga2O3 heterostructure in the AlScN gallium oxide solar-blind detector based on transverse electric field provided in this solution forms a transverse electric field, which can further promote the separation of photogenerated carriers; in addition, the transverse electric field directly acts on the movement of the domain wall of the AlScN layer, making the ferroelectric domains evenly distributed, reducing the leakage of the AlScN ferroelectric film, thereby improving the light-to-dark current ratio and responsiveness of the device.

[0009] In some embodiments, the AlScN layer is attached to the side surface of the gallium oxide block and covers a portion of the upper surface of the gallium oxide block. The AlScN layer and the gallium oxide block are arranged along the same lateral direction to form a lateral electric field.

[0010] Specifically, the AlScN layer is composed of an upper film portion and a lower film portion that are integrally arranged, wherein the upper film portion is located above the lower film portion, the length of the upper film portion is longer than the length of the lower film portion, and an inclusion region is formed between the upper film portion and the lower film portion, and one side of the gallium oxide block is wrapped in the inclusion region. At this time, the upper surface of the gallium oxide block is in contact with the upper film portion, and the side surface of the gallium oxide block is in contact with the lower film portion, so that the AlScN layer and the gallium oxide block are arranged along the same lateral direction to form a lateral electric field.

[0011] In some specific embodiments, the upper film and the lower film form an inverted "L" shape, where the AlScN layer wraps around one side of the gallium oxide block.

[0012] In some embodiments, the AlScN layer completely covers the side surface of the gallium oxide block and partially covers the upper surface of the gallium oxide block. Specifically, the lower portion of the AlScN film contacts the substrate, and the surface area of ​​the lower portion of the film attached to the side of the gallium oxide block is not less than the surface area of ​​the side surface of the gallium oxide block, and the surface area of ​​the upper portion of the film attached to the side of the gallium oxide block is less than the surface area of ​​the upper surface of the gallium oxide block.

[0013] Specifically, the surface area of ​​the side surface of the lower part of the film attached to the gallium oxide block is the same as the surface area of ​​the side surface of the gallium oxide block, the length of the side surface of the lower part of the film attached to the gallium oxide block is the same as the length of the side surface of the gallium oxide block, and the width of the side surface of the lower part of the film attached to the gallium oxide block is the same as the width of the side surface of the gallium oxide block. The width of the side surface of the upper part of the film attached to the gallium oxide block is the same as the width of the upper surface of the gallium oxide block, and the length of the side surface of the upper part of the film attached to the gallium oxide block is less than the length of the upper surface of the gallium oxide block.

[0014] In addition, the first metal electrode of the present invention is deposited on a side of the gallium oxide block away from the AlScN layer, and the second metal electrode is deposited on a side of the AlScN layer away from the gallium oxide block. The first metal electrode and the second metal electrode are placed on both sides of the AlScN / Ga2O3 heterostructure, and cooperate with the AlScN layer and the gallium oxide block to form a transverse electric field. The transverse electric field helps to accelerate the separation of photogenerated electron-hole pairs and reduce the probability of their recombination, thereby improving the response speed and efficiency of the device.

[0015] In some embodiments, the first metal electrode is deposited on the surface of the gallium oxide block and is in contact with the substrate at the bottom, and the second metal electrode is deposited on the surface of the AlScN layer and is in contact with the substrate at the bottom.

[0016] In this embodiment, the first metal electrode and the second metal electrode are selected from one or more of Au, Ag, Ti, Cr, Ni, Al, Pt, W, Cu, and Mg.

[0017] In addition, in some embodiments, the gallium oxide block includes a gallium oxide film grown on a substrate and a first metal hard mask layer grown on the gallium oxide film, wherein the metal in the first metal hard mask layer is one or more of Ti, Ni, Cr, W, Pt, Al or Ag, the thickness of the first metal hard mask layer is 10-500 nm, and the thickness of the gallium oxide film is about 200-300 nm. This is because a too thin gallium oxide layer will result in a lower light absorption rate, while a too thick gallium oxide layer will increase the recombination rate of photogenerated carriers, thereby reducing the photoelectric conversion efficiency. In addition, the first metal hard mask layer is set in this scheme to protect the gallium oxide photolithography pattern during the etching process.

[0018] Similarly, in some embodiments, the AlScN layer includes an AlScN ferroelectric film grown on a gallium oxide block and a second metal hard mask layer grown on the AlScN ferroelectric film, wherein the metal in the second metal hard mask layer is one or more of Ti, Ni, Cr, W, Pt, Al or Ag, the thickness of the second metal hard mask layer is 10 to 500 nm, and the thickness of the AlScN layer is between 10 and 70 nm. This is because an AlScN film that is too thin cannot provide enough separated charges, resulting in low photoelectric responsivity; an AlScN film that is too thick has a large ferroelectric flip voltage, resulting in device breakdown. Similarly, the purpose of setting the second metal hard mask layer in this solution is to protect the AlScN photolithography pattern during the etching process.

[0019] In a second aspect, the present invention provides a method for preparing an AlScN gallium oxide solar-blind detector based on a transverse electric field, comprising the following steps:

[0020] S1: growing a gallium oxide film on a substrate, growing a first metal hard mask layer on the gallium oxide film, and then etching to form an independent gallium oxide block;

[0021] S2: depositing and etching a first metal electrode on one side of each independent gallium oxide block;

[0022] S3: growing an AlScN ferroelectric film on the gallium oxide block, growing a second metal hard mask layer on the AlScN ferroelectric film, and then etching to form an AlScN layer, wherein the AlScN layer forms a lateral electric field with the gallium oxide block;

[0023] S4: depositing and etching a second metal electrode on one side of the AlScN layer.

[0024] In step S1, a gallium oxide thin film is grown on the substrate after the substrate is cleaned and dried.

[0025] In some embodiments, the substrate is ultrasonically cleaned with acetone, isopropanol and deionized water respectively and then dried with a nitrogen gun. This has the advantage of ensuring that the surface of the substrate is clean and free of impurities, providing a clean interface for subsequent processing. In some embodiments, the ultrasonic treatment is performed for 1-20 minutes, preferably for 20 minutes, and then dried with a nitrogen gun.

[0026] It should be noted that the advantage of this solution of first cleaning the substrate with acetone and then with isopropanol is that acetone can be dissolved in isopropanol solution. This method can help isopropanol remove excess acetone and avoid affecting the substrate and device performance.

[0027] In some embodiments, the substrate material of the substrate needs to match the gallium oxide film, and the substrate material of the substrate is selected from sapphire, single crystal silicon, silicon dioxide, gallium nitride, silicon carbide, quartz, gallium oxide, or a combination of any two or more thereof.

[0028] In step S1, a gallium oxide film is grown and deposited on a substrate by using MOCVD or PLD process. When the MOCVD process is used, the nitrogen flow rate range is 1-100 sccm, the oxygen flow rate range is 1-100 sccm, the argon flow rate range is 1-100 sccm, the growth pressure is 0.1-10 Pa, the growth temperature is 700-1000 °C, the RF power is 10-200 W, and the growth time is 10-90 min; when the PLD process is used, the laser energy is 1-500 mJ / pulse, the oxygen pressure is 0.1-10Pa, the deposition temperature is 500-1000 °C, and the deposition time is 10-60 min.

[0029] In addition, after the gallium oxide film is deposited and grown on the substrate in step S1, the gallium oxide film is photolithographically processed and a first metal hard mask layer is grown, and the oxide film on which the first metal hard mask layer is grown is etched to form an independent gallium oxide block.

[0030] In some embodiments, the metal of the first metal hard mask layer of the present solution is selected from one or more of Ti, Ni, Cr, W, Pt, Al or Ag, and the thickness of the first metal hard mask layer is 10-500 nm. In addition, in some embodiments, the present solution uses one or more etching processes of ICP etching, reactive ion etching (RIE) or ion beam etching (IBM) to etch the oxide film of the first metal hard mask layer to form an independent gallium oxide block.

[0031] It should be noted that a plurality of gallium oxide blocks are etched and deposited on the substrate of the present solution, wherein the plurality of gallium oxide blocks are distributed on the substrate in the form of an array. Correspondingly, the present solution uses an array-form template to etch the oxide film thin film for growing the first metal hard mask layer.

[0032] In step S2, a first metal electrode is deposited and etched on one side of each independent gallium oxide block by metal beam evaporation, thermal evaporation or magnetron sputtering.

[0033] In some embodiments, a first metal electrode is deposited and etched on one side of each independent gallium oxide block by overlaying.

[0034] In some embodiments, the metal material of the first metal electrode is selected from one or more of Au, Ag, Ti, Cr, Ni, Al, Pt, W, Cu, and Mg.

[0035] In step S3, an AlScN ferroelectric film is grown on the gallium oxide block on which the first metal electrode has been etched obtained in step S2, a second metal hard mask layer is grown on the AlScN ferroelectric film, and the AlScN ferroelectric film with the second metal hard mask layer is overetched to form an AlScN layer.

[0036] In some embodiments, an AlScN ferroelectric thin film is grown on the gallium oxide block on which the first metal electrode has been etched obtained in step S2 by sputtering, molecular beam epitaxy (MBE), or metal organic chemical vapor deposition (MOCVD).

[0037] In some embodiments, the metal in the second metal hard mask layer is one or more of Ti, Ni, Cr, W, Pt, Al or Ag, and the thickness of the second metal hard mask layer is 10-500 nm.

[0038] In some embodiments, one or more of plasma etching (ICP), reactive ion etching (RIE) or ion beam etching (IBM) are used to overlay-etch the AlScN ferroelectric film with the second metal hard mask layer to form an AlScN layer. It should be noted that the AlScN layer obtained by etching needs to correspond to the current gallium oxide block, and the AlScN layer fully covers the side surface of the gallium oxide block and partially covers the upper surface of the gallium oxide block, so that the AlScN layer forms a lateral electric field with the gallium oxide block. The specific structure can be referred to the above content.

[0039] In step S4, a second metal electrode is deposited and etched on one side of the AlScN layer by electron beam evaporation, thermal evaporation or magnetron sputtering.

[0040] In some embodiments, the second metal electrode is one or more of Au, Ag, Ti, Cr, Ni, Al, Pt, W, Cu, and Mg.

[0041] As described above, in a specific embodiment, the preparation method of the AlScN gallium oxide solar-blind detector based on the transverse electric field provided by the present scheme is to etch the gallium oxide single crystal film into an independent gallium oxide block by an inductively coupled plasma (ICP) etching device, and form a metal electrode on one side of the gallium oxide block by using standard electrode evaporation and etching technology, and then deposit a layer of AlScN ferroelectric film and photolithograph and etch it into an independent AlScN / Ga2O3 heterostructure device module, and use standard electrode evaporation technology to deposit and etch the metal electrode at the other end on the AlScN film to obtain the AlScN gallium oxide solar-blind detector based on the transverse electric field. The AlScN gallium oxide solar-blind detector based on the transverse electric field adopts the transverse electric field AlScN / Ga2O3 as the heterojunction structure, and utilizes the superior ferroelectric properties of AlScN under the transverse electric field flipping to improve the responsiveness of the device. At the same time, the low leakage of the heterojunction structure under the transverse electric field achieves a high light-to-dark current ratio and a high responsiveness.

[0042] Compared with the prior art, this technical solution has the following characteristics and beneficial effects:

[0043] This scheme provides a unique AlScN / Ga2O3 heterostructure design with a transverse electric field, in which the AlScN layer ferroelectric film not only covers the side of the gallium oxide block, but also partially covers its upper surface, forming an efficient transverse electric field. The transverse electric field can effectively promote the separation of photogenerated carriers and reduce their recombination probability, thereby improving the light-to-dark current ratio; at the same time, the transverse electric field also helps to optimize the domain distribution in the AlScN layer ferroelectric film, reduce the leakage of the AlScN ferroelectric film, and further improve the responsiveness of the device, which not only improves the light-to-dark current ratio and responsiveness of the solar-blind detector, but also enhances the stability and reliability of the device, which is of great significance for the development of high-performance solar-blind ultraviolet detectors. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a schematic diagram of the structure of the AlScN gallium oxide solar-blind detector based on the transverse electric field provided in this scheme.

[0045] Figure 2 This is a side schematic diagram of the AlScN gallium oxide solar-blind detector based on the transverse electric field provided in this scheme.

[0046] Figure 3 This is an IV curve diagram of the AlScN gallium oxide solar-blind detector based on the transverse electric field under ultraviolet light according to the first embodiment provided by the present invention.

[0047] Figure 4 It is a graph of the It curve of the AlScN gallium oxide solar-blind detector based on the transverse electric field under ultraviolet light according to the first embodiment provided in the present invention.

[0048] Figure 5 This is the IV curve of the gallium oxide heterojunction solar-blind detector obtained in comparative example 1.

[0049] Figure 6 It is the It curve of the gallium oxide heterojunction solar-blind detector obtained in Example 1. DETAILED DESCRIPTION

[0050] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0051] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0052] Embodiment 1:

[0053] Take sapphire as substrate, clean it with propanol, isopropanol and deionized water in turn, ultrasonically clean the substrate for 10 minutes, blow dry it with a nitrogen gun after cleaning, and deposit and grow gallium oxide film on the substrate by MOCVD method, wherein the deposition growth conditions are: nitrogen flow rate is 50 sccm, oxygen flow rate is 50 sccm, argon flow rate is 50 sccm, growth pressure is 5 Pa, growth temperature is 820 ℃, RF power is 98W, growth time is 40 min, and the substrate material is dried; then grow a first metal hard mask layer of Pt on the gallium oxide film for photolithography, wherein positive photoresist 5350 is used as photoresist, the exposure time is 3.8s, and the development time is 40s; the uniform gallium oxide film with the first metal hard mask layer is etched by ICP to obtain independent gallium oxide blocks, wherein the etching conditions are: argon flow rate is 45 sccm, CHF3 gas flow rate is 5 sccm, growth pressure is 4 mTorr, ICP power is 500 W, etching time is 1 min; an overlay method was used to deposit and etch a first metal electrode on one side of the gallium oxide block by electron beam evaporation, wherein the first metal electrode was Au / Ti, and the conditions for electron beam evaporation were as follows: Ti target power was 200 W, deposition thickness was 50 nm, Au target power was 500 W, deposition thickness was 50 nm, and growth time was 25 min; an AlScN ferroelectric film was grown by sputtering, wherein the sputtering conditions were as follows: using an AlSc alloy target, a sputtering power of 2.5 kW, a nitrogen and argon flow ratio of 85:15, a sputtering time of 2 min, and a thickness of 60 nm. Afterwards, a second metal hard mask layer whose metal material is Pt is grown on the grown AlScN ferroelectric film and overlayed, wherein the photolithography conditions are to use positive photoresist 5350, the exposure time is 3.8 s, and the development time is 40 s. The AlScN film with the second metal hard mask layer is etched by a plasma etching method, wherein the plasma etching conditions are an argon gas flow rate of 45 sccm, a CHF3 gas flow rate of 5 sccm, a power of 500 W, and an etching time of 1 min, and the etched AlScN layer forms a lateral electric field with the gallium oxide block; the second metal electrode is deposited and etched on one side of the AlScN by an overlay method using an electron beam evaporation method, wherein the second metal electrode is Au / Ti, and the electron beam evaporation conditions are: Ti target power is 200 W, the deposition thickness is 50 nm, Au target power is 500 W, the deposition thickness is 50 nm, and the growth time is 20 min.

[0054] Comparative Example 1: Take sapphire as the substrate, clean it with propanol, isopropanol and deionized water in turn, ultrasonically clean the substrate for 10 minutes, blow it dry with a nitrogen gun after cleaning, and deposit the first metal electrode by electron beam evaporation, wherein the first metal electrode is Au / Ti, and the conditions of electron beam evaporation are Ti target power of 200 W, deposition thickness of 50 nm, Au target power of 500 W, deposition thickness of 50 nm, and growth time of 20 min. A gallium oxide film is deposited and grown on the substrate by MOCVD method, wherein the deposition growth conditions are: nitrogen flow rate of 50 sccm, oxygen flow rate of 50 sccm, argon flow rate of 50 sccm, growth pressure of 5 Pa, growth temperature of 820 ℃, RF power of 98W, and growth time of 40 min. Subsequently, an AlScN ferroelectric film was grown on the gallium oxide film by sputtering, wherein the sputtering conditions were: sputtering power of 2.5 kW, nitrogen flow rate of 85 sccm, argon flow rate of 15 sccm, sputtering time of 2 min, and thickness of 60 nm. The grown AlScN ferroelectric film was deposited and etched by electron beam evaporation to form a second metal electrode, wherein the second metal electrode was Au / Ti, and the electron beam evaporation conditions were: Ti target power of 200 W, deposition thickness of 50 nm, Au target power of 500 W, deposition thickness of 50 nm, and growth time of 20 min.

[0055] Test performance: Current and response time of AlScN gallium oxide solar-blind detector based on transverse electric field in dark environment and under ultraviolet light.

[0056] Test Example 1:

[0057] The detectors obtained in Example 1 and Comparative Example 1 were placed in a dark room without light to test the dark current. The intensity of the ultraviolet light source was adjusted to 1 μw / cm 2 , aim the UV light source at the detector and start measuring the IV curve. Start from the reverse bias, gradually increase the forward bias, record the current value at each bias point, repeat the above process until the preset maximum bias range is reached to obtain the test data and draw the IV curve as shown in Figure 3 As shown, it is necessary to ensure that the light source is stable and without fluctuations during the entire process. Figure 3 is the IV curve of the AlScN gallium oxide solar-blind detector based on the transverse electric field obtained in Example 1 of this solution, Figure 5 This is the IV curve of the gallium oxide heterojunction solar-blind detector obtained in Example 1. It can be seen that the dark current of the AlScN gallium oxide solar-blind detector based on the lateral electric field under dark conditions is lower than 5 nA. At the same time, under the same lighting conditions, the photocurrent is close to 50 nA. The dark current is smaller, the photocurrent is larger, and the light-to-dark current ratio becomes higher.

[0058] Test Example 2:

[0059] The detectors obtained in Example 1 and Comparative Example 1 were placed in a dark room without illumination to test the initial dark current and transient current signal. The ultraviolet light source was turned on and the transient photocurrent changes of different detectors were immediately recorded. The time for the photocurrent to rise to the maximum value (response time) was observed and recorded. The ultraviolet light source was turned off and the time for the photocurrent to drop to the initial dark current level (recovery time) was recorded to obtain the test data and draw the It curve as shown in FIG. Figure 4 shown. Figure 4 It is the It curve of the AlScN gallium oxide solar-blind detector based on the transverse electric field obtained in Example 1 of this solution, Figure 6 This is the It curve of the gallium oxide heterojunction day-blind detector obtained in Example 1. It can be seen that the rise time decreases from 1.4 ms to 0.07 ms, and the fall time decreases from 15.2 ms to 0.7 ms, and the response speed becomes faster.

[0060] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to those of the present application fall within the protection scope of the present invention.

Claims

1. An AlScN gallium oxide solar-blind detector based on transverse electric field, characterized in that: include: A substrate and at least one AlScN / Ga2O3 heterostructure arranged on the surface of the substrate, wherein each AlScN / Ga2O3 heterostructure includes an independent gallium oxide block etched on the surface of the substrate, an AlScN layer deposited on one side of the gallium oxide block, a first metal electrode deposited on one side of the gallium oxide block, and a second metal electrode deposited on one side of the AlScN layer, and the AlScN layer forms a transverse electric field with the gallium oxide block, the AlScN layer is attached to the side surface of the gallium oxide block and the AlScN layer covers a portion of the upper surface of the gallium oxide block, the AlScN layer and the gallium oxide block are arranged along the same transverse direction to form a transverse electric field, the AlScN layer consists of an integrally arranged upper film part and a lower film part, wherein the upper film part is located above the lower film part, the length of the upper film part is longer than the length of the lower film part, an inclusion region is formed between the upper film part and the lower film part, and one side of the gallium oxide block is wrapped in the inclusion region.

2. The AlScN gallium oxide solar-blind detector based on transverse electric field according to claim 1, characterized in that: The surface area of ​​the side of the lower part of the film attached to the gallium oxide block is not less than the surface area of ​​the side surface of the gallium oxide block, and the surface area of ​​the side of the upper part of the film attached to the gallium oxide block is less than the surface area of ​​the upper surface of the gallium oxide block.

3. The AlScN gallium oxide solar-blind detector based on transverse electric field according to claim 1, characterized in that: The gallium oxide block includes a gallium oxide film grown on a substrate and a first metal hard mask layer grown on the gallium oxide film, wherein the metal in the first metal hard mask layer is one or more of Ti, Ni, Cr, W, Pt, Al or Ag.

4. The AlScN gallium oxide solar-blind detector based on transverse electric field according to claim 1, characterized in that: The AlScN layer includes an AlScN ferroelectric film grown on a gallium oxide block and a second metal hard mask layer grown on the AlScN ferroelectric film, wherein the metal in the second metal hard mask layer is one or more of Ti, Ni, Cr, W, Pt, Al or Ag.

5. The AlScN gallium oxide solar-blind detector based on transverse electric field according to claim 1, characterized in that: The first metal electrode is deposited on a side of the gallium oxide block away from the AlScN layer, and the first metal electrode is selected from one or more of Au, Ag, Ti, Cr, Ni, Al, Pt, W, Cu, and Mg; the second metal electrode is deposited on a side of the AlScN layer away from the gallium oxide block, and the second metal electrode is selected from one or more of Au, Ag, Ti, Cr, Ni, Al, Pt, W, Cu, and Mg.

6. A method for preparing an AlScN gallium oxide solar-blind detector based on a transverse electric field, characterized in that: The following steps are involved: S1: growing a gallium oxide film on a substrate, growing a first metal hard mask layer on the gallium oxide film, and then etching to form an independent gallium oxide block; S2: depositing and etching a first metal electrode on one side of each independent gallium oxide block; S3: growing an AlScN ferroelectric film on the gallium oxide block, and etching the second metal hard mask layer on the AlScN ferroelectric film to form an AlScN layer, wherein the AlScN layer forms a lateral electric field with the gallium oxide block, the AlScN layer is attached to the side surface of the gallium oxide block and the AlScN layer covers a portion of the upper surface of the gallium oxide block, the AlScN layer and the gallium oxide block are arranged along the same lateral direction to form a lateral electric field, the AlScN layer is composed of an upper film portion and a lower film portion that are integrally arranged, wherein the upper film portion is located above the lower film portion, the length of the upper film portion is longer than the length of the lower film portion, an inclusion region is formed between the upper film portion and the lower film portion, and one side of the gallium oxide block is wrapped in the inclusion region; S4: depositing and etching a second metal electrode on one side of the AlScN layer.

7. The method for preparing the AlScN gallium oxide solar-blind detector based on transverse electric field according to claim 6, characterized in that: A gallium oxide film is grown and deposited on a substrate by using an MOCVD or PLD process. When the MOCVD process is used, the nitrogen flow rate range is 1-100 sccm, the oxygen flow rate range is 1-100 sccm, the argon flow rate range is 1-100 sccm, the growth pressure is 0.1-10 Pa, the growth temperature is 700-1000 °C, the RF power is 10-200 W, and the growth time is 10-90 min. When the PLD process is used, the laser energy is 1-500 mJ / pulse, the oxygen pressure is 0.1-10 Pa, the deposition temperature is 500-1000 °C, and the deposition time is 10-60 min.

8. The method for preparing the AlScN gallium oxide solar-blind detector based on transverse electric field according to claim 6, characterized in that: An array-shaped template is used to etch the oxide film of the first metal hard mask layer.

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