Method for inhibiting continuous photoconductive effect of gallium oxide and application

Abstract

The invention belongs to the technical field of semiconductor devices, and relates to a method for inhibiting the continuous photoconductive effect of gallium oxide and application. The method comprises the following steps: providing a crystal gallium oxide material, and preheating the crystal gallium oxide material; the preheating temperature is not lower than the melting point of metal gallium; the method comprises the following steps: spreading liquid gallium oxide under an air condition, and forming an amorphous gallium oxide film layer on the surface of the spread liquid gallium oxide; enabling the surface of the preheated crystal gallium oxide material to be in contact with the amorphous gallium oxide film layer on the surface of the liquid gallium oxide under the condition that the liquid gallium oxide is kept in a liquid state, and enabling the amorphous gallium oxide film layer to be transferred to the surface of the crystal gallium oxide material; and nitriding, phosphorylating or vulcanizing the amorphous gallium oxide film layer on the surface of the crystal gallium oxide material, so that the amorphous gallium oxide film layer is converted into a gallium nitride film layer, a gallium phosphate film layer or a gallium sulfide film layer. According to the method provided by the invention, the response speed of a photoelectric detector is greatly improved while the material performance is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor devices, and relates to a method for suppressing the persistent photoconductivity effect of gallium oxide and its application. Background Art

[0002] Disclosing the information of this background art section is only intended to enhance the overall understanding of the present invention, and is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] As a kind of III-VI group semiconductor material with an ultra-wide bandgap (4.2 - 5.1 eV), gallium oxide (Ga2O3) has attracted much attention in the field of photodetection due to its high light absorption coefficient, excellent thermal / chemical stability, anti-radiation performance and low-cost characteristics. This material has a high transmittance in the ultraviolet to visible light range, can meet the requirements of solar-blind ultraviolet detection, and is widely used in military and civilian fields such as ultraviolet communication, missile warning, biomedical detection, fire monitoring and high-voltage power equipment status monitoring. However, gallium oxide-based optoelectronic devices are restricted by the persistent photocurrent (PPC, also known as the persistent photoconductivity effect) phenomenon in practical applications. The PPC effect stems from the long-term trapping of photo-generated carriers by internal defects in the material, resulting in a significant extension of the photocurrent response recovery time, severely reducing the time resolution and dynamic detection performance of the device, thus restricting the practical application process of gallium oxide photodetectors. Summary of the Invention

[0004] In order to solve the deficiencies of the prior art, the purpose of the present invention is to provide a method for suppressing the persistent photoconductivity effect of gallium oxide and its application. The method provided by the present invention not only improves the material performance, but also greatly improves the response speed of its optoelectronic detection device. At the same time, it can achieve a detection effect with low energy consumption or even without external energy. In this way, the response band can also be broadened, and it can be used for broadband detection, especially suitable for the field of optoelectronic detection.

[0005] In order to achieve the above purpose, the technical solution of the present invention is as follows: In the first aspect, a method for suppressing the persistent photoconductivity effect of gallium oxide includes the following steps: Provide a crystalline gallium oxide material and preheat the crystalline gallium oxide material; the preheating temperature is not lower than the melting point of metallic gallium; Under air conditions, spread liquid gallium oxide, and an amorphous gallium oxide film layer is formed on the surface of the spread liquid gallium oxide; Under the condition of keeping the liquid gallium oxide in a liquid state, bring the surface of the preheated crystalline gallium oxide material into contact with the amorphous gallium oxide film layer on the surface of the liquid gallium oxide, so that the amorphous gallium oxide film layer is transferred to the surface of the crystalline gallium oxide material; Nitridation, phosphorylation or sulfidation is carried out on the amorphous gallium oxide film layer on the surface of the gallium oxide crystal material, so that the amorphous gallium oxide film layer is transformed into a gallium nitride film layer, a gallium phosphate film layer or a gallium sulfide film layer.

[0006] In the present invention, an amorphous gallium oxide film layer is first formed on the gallium oxide crystal material, and then the amorphous gallium oxide film is transformed into a gallium nitride film layer, a gallium phosphate film layer or a gallium sulfide film layer through nitridation, phosphorylation or sulfidation, thereby constructing a heterojunction to form a built-in electric field, and this built-in electric field can significantly inhibit the persistent photoconductivity effect of the gallium oxide crystal.

[0007] In the present invention, an amorphous gallium oxide film layer is formed on the surface of liquid gallium metal, and under the condition of keeping the liquid gallium oxide in a liquid state, the amorphous gallium oxide film layer on the surface of the liquid gallium metal is transferred to the surface of the gallium oxide crystal material by a dip-pressing method. This method uses the amorphous gallium oxide film layer on the surface of the liquid gallium metal, and the thickness of this film layer is relatively thin, with good compactness, uniformity and flexibility. After being transferred to the surface of the gallium oxide crystal material and transformed, it can better construct a built-in electric field, and the steps are simple and the cost is reduced. In addition, by increasing the number of times of transferring the gallium oxide film layer, the thickness of the amorphous gallium oxide film layer can be accumulated, and thus the thickness of the amorphous gallium oxide film layer can be regulated.

[0008] However, it is found in the experiment of the present invention that when the amorphous gallium oxide film layer is transferred to the surface of the gallium oxide crystal material by simple dip-pressing, problems such as discontinuity and cracking often occur in the transferred film layer, resulting in a decrease in the success rate of completely transferring the amorphous gallium oxide film layer to the surface of the gallium oxide crystal material. Therefore, further in the present invention, the surface of the gallium oxide crystal material is subjected to a hydrophilic treatment, and the gallium oxide crystal material after the hydrophilic treatment is preheated. After the hydrophilic treatment, there are many polar groups or groups that can form hydrogen bonds on the surface, such as hydroxyl groups (-OH), carbonyl groups (C=O), etc. These groups can form strong chemisorption with gallium (Ga) atoms or oxygen (O) atoms in the amorphous gallium oxide, which is beneficial to improving the integrity of the transfer of the amorphous gallium oxide film layer, thereby improving the success rate of the transferred film layer having problems such as discontinuity and cracking, and making the amorphous gallium oxide film layer completely transferred to the surface of the gallium oxide crystal material.

[0009] In a second aspect, an application of the above method for suppressing the persistent photoconductivity effect of gallium oxide in the preparation of gallium oxide crystal-based optoelectronic devices.

[0010] The beneficial effects of the present invention are: 1. Under the condition of keeping liquid gallium oxide in a liquid state, the amorphous gallium oxide film layer on the surface of liquid gallium oxide is transferred to the surface of a gallium oxide crystal material by means of pressing and dipping. Since liquid gallium metal is plastic, the amorphous gallium oxide film layer can cover any desired plane, which is applicable to the preparation of gallium oxide crystals in various forms and has universality. On this basis, the amorphous gallium oxide film layer is nitrided, phosphorylated or sulfided, and an internal built-in electric field is formed by constructing a heterojunction, which significantly inhibits the persistent photoconductivity effect of gallium oxide, improves the device performance of gallium oxide, and constructs a self-powered photodetector at the same time, further expanding its application in advanced optoelectronic devices.

[0011] 2. By performing a hydrophilic treatment on the surface of the gallium oxide crystal material, the adsorption performance of the surface of the gallium oxide crystal material for the amorphous gallium oxide film layer is increased, making it easier for the amorphous gallium oxide film layer to be completely transferred to the surface of the gallium oxide crystal material, and improving the success rate of the complete transfer of the amorphous gallium oxide film layer to the surface of the gallium oxide crystal material. In addition, through the partial surface modification treatment of the gallium oxide crystal material, and then transferring the amorphous gallium oxide film layer to the non-hydrophobic modified part of the surface of the gallium oxide crystal material, a patterned amorphous gallium oxide film layer can be obtained on the surface of the gallium oxide crystal material, increasing the flexibility of subsequent device design, without complex photolithography or etching treatment, greatly simplifying the subsequent device preparation process, and being beneficial to promoting the innovation of the gallium oxide device structure.

[0012] 3. The method for constructing the heterojunction adopted in the present invention has low cost, easily available raw materials, and no pollution to the environment, and can construct heterojunctions for a variety of semiconductor materials, meeting the requirements of various devices for precursors. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0014] Figure 1 It is a component content diagram of the heterojunction obtained in Example 1.

[0015] Figure 2 It is a comparison diagram of the response time before and after forming a heterojunction photodetector obtained in Example 1; wherein, a is a normalized intensity diagram from 0 to 140 s, and b is a normalized intensity diagram from 0 to 1000 ms.

[0016] Figure 3 It is a component content diagram of the heterojunction obtained in Example 2.

[0017] Figure 4The contrast diagram of the response time before and after forming the heterojunction photodetector obtained in Example 2; among them, a is the normalized intensity diagram from 0 to 150 s, and b is the normalized intensity diagram from 0 to 1000 ms.

[0018] Figure 5 It is the content diagram of the failed heterojunction component obtained in Comparative Example 1.

[0019] Figure 6 It is the response time diagram of the failed heterojunction photodetector obtained in Comparative Example 2.

[0020] Figure 7 It is the SEM diagram of the topmost gallium oxide amorphous film obtained in Comparative Example 3. Detailed implementation manners

[0021] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanations of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0022] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] In view of the fact that the performance of gallium oxide-based optoelectronic devices is poor due to the persistent photoconductivity effect, making it difficult to be applied, the present invention proposes a method and application for suppressing the persistent photoconductivity effect of gallium oxide.

[0024] A typical embodiment of the present invention provides a method for suppressing the persistent photoconductivity effect of gallium oxide, including the following steps: Providing a crystalline gallium oxide material and preheating the crystalline gallium oxide material; the preheating temperature is not lower than the melting point of metallic gallium; Under air conditions, spreading liquid gallium oxide, and forming an amorphous gallium oxide film layer on the surface of the spread liquid gallium oxide; Under the condition of keeping the liquid gallium oxide in a liquid state, bringing the surface of the preheated crystalline gallium oxide material into contact with the amorphous gallium oxide film layer on the surface of the liquid gallium oxide, so that the amorphous gallium oxide film layer is transferred to the surface of the crystalline gallium oxide material; Nitriding, phosphorylating or sulfiding the amorphous gallium oxide film layer on the surface of the crystalline gallium oxide material, so that the amorphous gallium oxide film layer is converted into a gallium nitride film layer, a gallium phosphate film layer or a gallium sulfide film layer.

[0025] In some embodiments, the surface of the gallium oxide crystal material is subjected to a hydrophilic treatment, and the gallium oxide crystal material after the hydrophilic treatment is preheated. The hydrophilic treatment described in the present invention can be carried out by covering the surface of the gallium oxide crystal material with a hydrophilic reagent, such as evaporation, spraying, soaking, etc., or can be carried out by plasma treatment.

[0026] The liquid gallium oxide is spread on a substrate. In some embodiments, the material of the substrate for spreading the liquid gallium oxide is glass, quartz, or a silicon wafer with an oxide layer, etc. This material is beneficial for spreading the liquid gallium oxide.

[0027] Meanwhile, the present invention can adjust the adsorption performance between the amorphous gallium oxide film layer and the surface of the gallium oxide crystal material by performing hydrophilic treatment or hydrophobic treatment on the surface of the gallium oxide crystal material, so as to achieve patterning treatment.

[0028] After the surface of the gallium oxide crystal material is subjected to hydrophilic treatment in the present invention, the amorphous gallium oxide film layer on the surface of the liquid gallium oxide is transferred to the hydrophilic part of the surface of the gallium oxide crystal material. After the surface of the gallium oxide crystal material is subjected to hydrophobic treatment in the present invention, the amorphous gallium oxide film layer on the surface of the liquid gallium oxide is transferred to the non-hydrophobic part of the surface of the gallium oxide crystal material. Since after hydrophilic treatment, the adsorption performance between the amorphous gallium oxide film layer and the surface of the gallium oxide crystal material can be increased, and the efficiency and integrity of the transfer of the amorphous gallium oxide film layer to the surface of the gallium oxide crystal material can be improved; therefore, the present invention preferably performs hydrophilic treatment on the surface of the gallium oxide crystal material to achieve patterning treatment.

[0029] When performing the steps of hydrophilic treatment or hydrophobic treatment in the present invention, it can be carried out by covering the surface of the gallium oxide crystal material with a hydrophilic reagent or a hydrophobic reagent, or can be carried out by plasma treatment.

[0030] Specifically, the hydrophilic reagent used for hydrophilic treatment is maleic anhydride, acrylic acid, or methacrylic acid, etc.

[0031] Specifically, the hydrophobic reagent used for hydrophobic treatment is trimethylchlorosilane, silane solution, polytetrafluoroethylene (PTFE), polyolefin, or olefin.

[0032] In some embodiments, a mask plate is used to perform hydrophilic treatment on a part of the surface of the gallium oxide crystal material. The shape of the mask plate can be any shape in a straight, curved, wrinkled state, etc.

[0033] In some embodiments, the methods of hydrophilic treatment or hydrophobic treatment are evaporation, spraying, and soaking.

[0034] In some embodiments, the liquid gallium oxide is maintained in a liquid state by heating the substrate. Specifically, the temperature for heating the substrate is 35 - 130 °C. Specifically, the old gallium oxide on the surface of the liquid gallium oxide is removed to expose the fresh liquid gallium oxide, and an amorphous gallium oxide film layer is formed on the surface of the fresh liquid gallium oxide under air conditions.

[0035] In some embodiments, after the surface of the crystalline gallium oxide material is hydrophilically treated, it starts to be preheated, and within 3.0 min, the surface of the crystalline gallium oxide material after hydrophilic treatment is brought into contact with the amorphous gallium oxide film layer on the surface of the liquid gallium oxide. This condition is conducive to the transfer of the amorphous gallium oxide film layer.

[0036] In some embodiments, the contact time between the surface of the preheated crystalline gallium oxide material and the amorphous gallium oxide film layer on the surface of the liquid gallium oxide is 0.01 - 10 s. This condition is conducive to the transfer of the amorphous gallium oxide film layer.

[0037] In some embodiments, after the transfer of the amorphous gallium oxide film layer, the residual gallium metal on the surface of the amorphous gallium oxide film layer is cleaned in boiling ethanol. Specifically, when cleaning, the force in contact with the amorphous gallium oxide thin film is less than 2 N to avoid damaging the amorphous gallium oxide film layer.

[0038] In some embodiments, the nitridation temperature is 600 - 900 °C and the nitridation time is 30 - 120 min. Research shows that under these conditions, the nitrogen source can react with the amorphous gallium oxide thin film to form a two-dimensional gallium nitride film layer, and the crystalline gallium oxide material will not be affected by the nitridation.

[0039] In some embodiments, the nitrogen source used for nitridation is urea. Specifically, urea is evaporated and introduced into the crystalline gallium oxide material containing the amorphous gallium oxide film layer. More specifically, the evaporation temperature of urea is 300 - 500 °C. More specifically, the distance between urea and the crystalline gallium oxide material containing the amorphous gallium oxide film layer is 10 - 15 cm. More specifically, the carrier gas for transporting the urea vapor is nitrogen.

[0040] In some embodiments, the sulfidation temperature is 500 - 800 °C and the sulfidation time is 30 - 120 min. Research shows that under these conditions, the sulfur source can react with the amorphous gallium oxide thin film to form a two-dimensional gallium sulfide film layer, and the crystalline gallium oxide material will not be affected by the sulfidation.

[0041] In some embodiments, the sulfur source used for sulfidation is sulfur. Specifically, sulfur is evaporated and introduced into the crystalline gallium oxide material containing the amorphous gallium oxide film layer. More specifically, the evaporation temperature of sulfur is 150 - 300 °C. More specifically, the distance between sulfur and the crystalline gallium oxide material containing the amorphous gallium oxide film layer is 12.5 - 15 cm. More specifically, the carrier gas for transporting the sulfur vapor is nitrogen.

[0042] In some embodiments, the temperature of phosphorylation is 300 - 400 °C, and the time of phosphorylation is 60 - 120 min. Research shows that under such conditions, a phosphorus source can react with an amorphous gallium oxide thin film to form a two-dimensional gallium phosphate film layer, and the crystalline gallium oxide material will not be affected by nitridation.

[0043] In some embodiments, the phosphorus source for phosphorylation is phosphoric acid (H3PO4). Specifically, phosphoric acid is evaporated and introduced into a crystalline gallium oxide material containing an amorphous gallium oxide film layer. More specifically, the evaporation temperature of phosphoric acid is 300 - 400 °C. More specifically, the distance between the phosphoric acid and the crystalline gallium oxide material containing an amorphous gallium oxide film layer is 10 - 15 cm. More specifically, the carrier gas for transporting phosphoric acid vapor is nitrogen.

[0044] In some embodiments, the following steps are preferred: Step 1: Take a large piece of solid metal gallium with a purity of 99.9999% or above, place it on a hot stage at 90 - 130 °C in an anaerobic glove box to heat and melt it, and then dispense the melted metal gallium into plastic bottles of 5 - 50 ml for subsequent use. Place the plastic bottles filled with metal gallium in an anaerobic environment for storage. Clean the crystalline gallium oxide material with persistent photoconductivity effect 1 - 3 times in sequence using water, acetone, and ethanol, and then perform a hydrophilic treatment on the surface of the crystalline gallium oxide material. If patterning is required, a pre-designed template needs to be prepared to mask the gallium oxide thin film; in the hydrophilic treatment, use evaporation, spraying, or soaking methods to pattern the crystalline gallium oxide material with a surfactant (such as maleic anhydride, acrylic acid, or methacrylic acid as hydrophilic surfactants) so that the surface of the crystalline gallium oxide material that needs to be covered with an amorphous gallium oxide film layer is a hydrophilic region; Step 2: Place the liquid metal gallium on a glass slide and make it spread out flat. Place the glass slide on a hot stage at 35 °C - 130 °C, and quickly scrape off the old liquid gallium on the surface of the metal gallium with glass, quartz, silicon wafers, etc. to expose the fresh liquid gallium; take down the mask template on the surface of the crystalline gallium oxide material after hydrophilic treatment, preheat it, and quickly cover the surface of the crystalline gallium oxide material after hydrophilic treatment onto the fresh liquid gallium surface within 3 minutes, and then quickly remove it within 10 seconds; if it is necessary to clean the residual metal gallium on the surface, clean it with a cotton swab that does not shed cotton wool in boiling alcohol. The force when the cotton swab contacts the amorphous gallium oxide film layer should be less than 2 N until the metal gallium on the surface is cleaned up; Step 3: Construct the required heterojunction according to the Fermi level and nitride, phosphorylate, and sulfide the top amorphous gallium oxide film layer; if nitridation is required, place urea (50 mg - 2 g) on the alumina boat in the lower temperature area of the tube furnace. The urea particles can generate ammonia gas; invert the gallium oxide crystal material covered with the amorphous gallium oxide film layer and place it in the center of another alumina boat. The distance between the two quartz boats is 10 - 15 cm. Heat the urea to 300 - 500 °C and heat the temperature at the gallium oxide crystal material to 600 - 900 °C. The heating rate at both places is 10 - 15 °C / min. Use nitrogen with a flow rate of 45 - 55 sccm as the carrier gas; the heat preservation time is 30 - 90 min for both. After the synthesis, cool it naturally to room temperature; the patterned amorphous gallium oxide film layer reacts with ammonia gas to obtain a two-dimensional gallium nitride film layer; If a gallium sulfide film layer needs to be covered on the surface, invert the gallium oxide crystal material covered with the amorphous gallium oxide film layer and place it in the center of another alumina boat. The sulfur powder is 50 mg - 1 g, and the sulfur powder is about 12.5 - 15 cm away from the gallium oxide crystal material; the evaporation temperature of the sulfur powder is about 150 - 300 °C; heat the temperature at the gallium oxide crystal material to 500 - 800 °C; in order to maintain the uniformity and best effect of the product, use a heating rate of 5 - 10 °C / min; use nitrogen with a constant flow rate of 45 - 55 sccm as the carrier gas, and the heat preservation time is 30 - 90 min; a heterojunction with a patterned gallium sulfide film covered on the surface can be obtained; If a GaPO4 film layer needs to be covered on the surface, that is, use phosphoric acid powder (50 mg - 2 g) as the phosphorus source. Invert the gallium oxide crystal material covered with the amorphous gallium oxide thin film and place it in the center of the alumina boat, 10 - 15 cm away from the phosphoric acid powder. Use nitrogen as the carrier gas with a flow rate of 0.5 - 0.7 L / min. Heat the gallium oxide crystal material and the phosphoric acid powder in the same temperature zone at 300 - 400 °C for 60 - 90 min; a heterojunction with a patterned GaPO4 thin film covered on the surface can be obtained.

[0045] Another embodiment of the present invention provides an application of the above method for suppressing the persistent photoconductivity effect of gallium oxide in the preparation of gallium oxide-based optoelectronic devices.

[0046] In some embodiments, it also includes the process of preparing electrodes. Specifically, the electrodes are located on the surface of the gallium oxide crystal material and on the surface of the gallium nitride film layer, gallium phosphate film layer, or gallium sulfide film layer. Specifically, the method for preparing the electrodes is evaporation coating. Specifically, the thickness of the electrodes is 50 - 500 nm.

[0047] In order to enable those skilled in the art to understand the technical solution of the present invention more clearly, the following will specifically describe the technical solution of the present invention in detail with reference to specific examples and comparative examples.

[0048] Example 1: 1. Selection and Treatment of Raw Materials 1.1. Take large solid gallium metal with a purity of 99.9999%. Under anaerobic conditions, preheat the hot stage in the glove box to 100 °C, and use the preheated hot stage to melt the gallium metal. Divide the melted gallium metal into 5 mL plastic bottles for subsequent use. Place the plastic bottles filled with gallium metal in a vacuum chamber and store them in a vacuum environment.

[0049] 1.2. Clean the gallium oxide wafer with persistent photoconductivity effect successively with water, acetone, and ethanol, and each solvent is cleaned 3 times.

[0050] 1.3. Prepare the designed mask plate in advance and mask the gallium oxide wafer. Adopt the spraying method and perform patterned hydrophilic treatment on the masked gallium oxide wafer with maleic anhydride solution.

[0051] 2. Construction Process of Heterojunction 2.1. Place the glass slide on a 35 °C hot stage, place the gallium metal on the glass slide, and melt the gallium metal by heating with the hot stage to make the liquid gallium metal in a flat state.

[0052] 2.2. Quickly scrape the old gallium oxide on the surface of the liquid gallium metal in step 2.1 with glass to expose the fresh gallium droplets.

[0053] 2.3. Remove the mask plate on the surface of the gallium oxide wafer after the patterned hydrophilic treatment in step 1. Then place it on a 40 °C hot stage for preheating, and quickly cover the surface of the gallium oxide wafer after hydrophilic treatment on the fresh gallium droplet surface obtained in step 2.2 within 3 minutes. Then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Use a cotton swab that does not shed cotton wool to clean the residual gallium metal in boiling alcohol with a force of 1N.

[0054] 2.4. Take 50 mg of urea and place it on the alumina boat in the lower temperature area of the tube furnace. Invert the gallium oxide wafer covered with a patterned amorphous gallium oxide film layer and place it in the center of another alumina boat (i.e., the amorphous gallium oxide film layer is above the gallium oxide wafer). The distance between the two quartz boats is 10 cm. Heat the urea to 300 °C and heat the temperature at the gallium oxide wafer to 600 °C. The heating rate at both places is 10 °C / min, and nitrogen with a constant flow rate of 50 sccm is used as the carrier gas. The insulation time is 30 minutes, and after the synthesis, it is naturally cooled to room temperature. The patterned amorphous gallium oxide film layer reacts with ammonia gas to obtain a two-dimensional gallium nitride film layer.

[0055] In a mask method, a 100-nm-thick titanium metal is evaporated on both the gallium oxide wafer and the two-dimensional gallium nitride film layer to construct a photodetector.

[0056] The element contents of the upper two-dimensional gallium nitride film layer and the lower gallium oxide wafer obtained in this embodiment were both tested at two positions, as Figure 1 shown. It can be seen from Figure 1 that the heterojunction obtained in this embodiment has a very high purity, and the lower gallium oxide wafer is not nitrided. Figure 2 It can be seen that after the heterojunction is constructed, compared with only using the gallium oxide wafer before construction, the persistent photoconductivity effect of the photodetector constructed in this embodiment is significantly suppressed.

[0057] Example 2: 1. Selection and treatment of raw materials 1.1. Take a large block of solid gallium metal with a purity of 99.9999%. Under anaerobic conditions, preheat the hot stage in the glove box to 100 °C, and use the preheated hot stage to melt the gallium metal. Then, divide the melted gallium metal into 10-ml plastic bottles for subsequent use. Place the plastic bottles filled with gallium metal in a vacuum device and store them in a vacuum environment.

[0058] 1.2. Clean the gallium oxide wafer with persistent photoconductivity effect successively using water, acetone, and ethanol, with each solvent being cleaned 3 times.

[0059] 1.3. Prepare a pre-designed mask template in advance, mask the gallium oxide wafer, and use acrylic to perform patterned hydrophilic treatment on the masked gallium oxide wafer by evaporation.

[0060] 2. Construction process of the heterojunction 2.1. Place the glass sheet on a 45 °C hot stage, place the gallium metal on the glass sheet, and heat it through the hot stage to melt the gallium metal and make the liquid gallium metal in a flat state.

[0061] Delete the old gallium oxide on the surface of the liquid gallium metal in step 2.1 quickly with glass to expose the fresh liquid gallium.

[0062] 2.3. Remove the mask template on the surface of the gallium oxide wafer after the patterned hydrophilic treatment in step 1.3, then place it on a 40 °C hot stage for preheating, and quickly cover the surface of the gallium oxide wafer after the hydrophilic treatment on the surface of the fresh gallium droplet obtained in step 2.2 within 3 minutes. Then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after the hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the amorphous gallium oxide film layer with a cotton swab that does not shed cotton wool in boiling alcohol, and the force when the cotton swab contacts the amorphous gallium oxide film layer is 1 N.

[0063] 2.4. Place 50 mg of sulfur powder on an alumina boat in the lower temperature region of a tube furnace. Invert the gallium oxide wafer covered with an amorphous gallium oxide film layer and place it at the center of another alumina boat. The distance between the sulfur powder and the gallium oxide wafer is about 12.5 cm. The evaporation temperature of the sulfur powder is about 150 °C. Heat the temperature at the gallium oxide wafer to 500 °C. Use a heating rate of 5 °C / min. Use nitrogen gas with a constant flow rate of 50 sccm as the carrier gas, and the heat preservation time is 30 min. The patterned amorphous gallium oxide film layer reacts with sulfur vapor to obtain a two-dimensional gallium sulfide film layer. Thus, a heterojunction with a patterned gallium sulfide film layer on its surface can be obtained.

[0064] Adopt a masking method to evaporate 100-nm-thick titanium metal on the gallium oxide wafer and the two-dimensional gallium sulfide film layer to construct a photodetector.

[0065] The element contents of the upper two-dimensional gallium sulfide film layer and the lower gallium oxide wafer obtained in this example were both tested at two positions, as Figure 3 shown. As Figure 3 can be seen, the purity of the heterojunction obtained in this example is very high, and the lower gallium oxide wafer is not sulfided. Figure 4 It can be seen that after constructing the heterojunction, compared with only using gallium oxide before construction, the persistent photoconductivity effect of the photodetector constructed in this example is significantly suppressed.

[0066] Example 3: 1. Selection and treatment of raw materials 1.1. Take large-piece solid gallium with a purity of 99.9999%. Under anaerobic conditions, preheat the hot stage in the glove box to 100 °C, and use the preheated hot stage to melt the gallium metal. Divide the melted gallium metal into 10-ml plastic bottles for subsequent use. Place the plastic bottles filled with gallium metal in a vacuum device and store them in a vacuum environment.

[0067] 1.2. Wash the gallium oxide crystal with persistent photoconductivity effect with water, acetone, and ethanol in sequence.

[0068] 1.3. Prepare a pre-designed mask template in advance and mask the gallium oxide wafer. Adopt a spraying method to perform patterned hydrophilic treatment on the masked gallium oxide wafer with methacrylic acid solution.

[0069] 2. Construction process of the heterojunction 2.1. Place a glass slide on a 50 °C hot stage, place the gallium metal on the glass slide, and melt the gallium metal by heating with the hot stage to make the liquid gallium metal in a flat state.

[0070] 2.2. Quickly scrape the old gallium oxide on the surface of the liquid gallium metal in Step 2.1 with glass to expose fresh gallium droplets.

[0071] 2.3. Remove the mask on the surface of the gallium oxide wafer after the hydrophilic treatment patterned in Step 1.3, then place it on a hot plate preheated to 40 °C for preheating, and quickly cover the surface of the gallium oxide wafer after the hydrophilic treatment onto the surface of the fresh gallium droplets obtained in Step 2.2 within 3 minutes, and then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after the hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the surface metal gallium with a cotton swab that does not shed cotton wool in boiling alcohol, and the force when the cotton swab contacts the amorphous gallium oxide film is 1 N.

[0072] 2.4. Take 50 mg of phosphoric acid powder and place it on an alumina boat in the lower temperature region of a tube furnace. Invert the gallium oxide wafer covered with the patterned amorphous gallium oxide film layer and place it at the center of another alumina boat (i.e., the amorphous gallium oxide film layer is above the gallium oxide wafer), and the distance between the gallium oxide wafer and the phosphoric acid powder is 10 cm. Use nitrogen as the carrier gas with a flow rate of 0.6 L / min, and heat the gallium oxide wafer and the phosphoric acid powder at 300 °C in the same temperature zone for 60 minutes. The patterned amorphous gallium oxide film layer reacts with phosphorus vapor to obtain a two-dimensional GaPO4 film layer. Thus, a heterojunction with a patterned GaPO4 film layer on the surface can be obtained.

[0073] Using a mask method, deposit titanium metal with a thickness of 100 nm on both the gallium oxide wafer and the two-dimensional GaPO4 film layer to construct a photodetector.

[0074] The element contents of the upper two-dimensional GaPO4 film layer and the lower gallium oxide wafer obtained in this example were both tested at two positions. The test results show that the heterojunction obtained in this example has a very high purity, and the lower gallium oxide wafer was not phosphorylated. The results of the photoelectric detection response time detection show that the persistent photoconductivity effect of the photodetector constructed in this example was significantly inhibited.

[0075] Example 4: 1. Selection and treatment of raw materials 1.1. Take a large piece of solid gallium metal with a purity of 99.9999%. Under anaerobic conditions, preheat the hot plate in the glove box to 90 °C, and use the preheated hot plate to melt the gallium metal. Divide the melted gallium metal into 10 ml plastic bottles for subsequent use. Place the plastic bottles filled with gallium metal in a vacuum chamber and store them in a vacuum environment.

[0076] 1.2. Wash the gallium oxide wafer with persistent photoconductivity effect successively with water, acetone, and ethanol, and each solvent is washed 3 times.

[0077] 1.3. Prepare the pre-designed mask in advance, mask the gallium oxide wafer, and perform patterned hydrophilic treatment on the masked gallium oxide wafer with maleic anhydride solution by spraying.

[0078] 2. Construction process of heterojunction 2.1. Place the glass slide on a hot plate at 50 °C, place gallium metal on the glass slide, melt the gallium metal by heating with the hot plate, and make the liquid gallium metal in a flat state.

[0079] 2.2. Quickly scrape the old gallium oxide on the surface of the liquid gallium metal in step 2.1 with the glass to expose the fresh liquid gallium.

[0080] 2.3. Remove the mask on the surface of the gallium oxide wafer after the patterned hydrophilic treatment in step 1.3, then place it on a hot plate at 40 °C for preheating, and quickly cover the surface of the gallium oxide wafer after hydrophilic treatment onto the surface of the fresh gallium droplets obtained in step 2.2 within 3 minutes, and then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the residual gallium metal with a cotton swab that does not shed cotton wool in boiling alcohol with a force of 1N.

[0081] 2.4. Take 70 mg of urea and place it on the alumina boat in the lower temperature area of the tube furnace. Invert the gallium oxide wafer covered with the amorphous gallium oxide film layer and place it in the center of another alumina boat. The distance between the two quartz boats is 10 cm. Heat the urea to 400 °C and heat the temperature at the gallium oxide wafer to 700 °C. The heating rate at both places is 15 °C / min, and use nitrogen gas with a flow rate of 50 sccm as the carrier gas. The insulation time is 60 min for both, and after the synthesis, it is naturally cooled to room temperature. The patterned amorphous gallium oxide film layer reacts with ammonia gas to obtain a two-dimensional gallium nitride film layer.

[0082] By using the mask method, evaporate a 100-nm-thick metal titanium as the electrode on both the gallium oxide wafer and the two-dimensional gallium nitride film layer to construct a photodetector.

[0083] The element contents at two positions of the upper two-dimensional gallium nitride film layer and the lower gallium oxide wafer obtained in this example were both tested. The results show that the purity of the heterojunction obtained in this example is very high, and the lower gallium oxide wafer was not nitrided. The results of the photoelectric detection response time test show that the persistent photoconductivity effect of the photodetector constructed in this example was significantly inhibited.

[0084] Example 5: 1. Selection and treatment of raw materials 1.1. Take a large piece of solid gallium metal with a purity of 99.9999%. Under anaerobic conditions, preheat the hot stage in the glove box to 100 °C, and use the preheated hot stage to melt the gallium metal. Then, dispense the melted gallium into 5-mL plastic bottles for subsequent use. Place the plastic bottles filled with gallium in a vacuum chamber and store them in a vacuum environment.

[0085] 1.2. Clean the gallium oxide wafer with persistent photoconductivity effect successively using water, acetone, and ethanol.

[0086] 1.3. Prepare a pre-designed mask in advance and mask the gallium oxide wafer. Use evaporation to perform patterned hydrophilic treatment on the masked gallium oxide wafer with acrylic acid.

[0087] 2. Construction process of heterojunction 2.1. Place the glass slide on a 50 °C hot stage, put the gallium metal on the glass slide, and heat it through the hot stage to melt the gallium metal, making the liquid gallium spread out flat.

[0088] 2.2. Quickly scrape the old gallium oxide on the surface of the liquid gallium in step 2.1 with the glass to expose fresh gallium droplets.

[0089] 2.3. Remove the mask on the surface of the gallium oxide wafer after the patterned hydrophilic treatment in step 1.3, then place it on a 40 °C hot stage for preheating, and quickly cover the surface of the gallium oxide wafer after the hydrophilic treatment onto the surface of the fresh gallium droplets obtained in step 2.2 within 3 minutes. Then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after the hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the gallium oxide thin film with a cotton swab that does not shed cotton wool in boiling alcohol, and the force when the cotton swab contacts the amorphous gallium oxide film is 1 N.

[0090] 2.4. Take 50 mg of sulfur powder and place it on an alumina boat in the lower temperature area of the tubular furnace. Invert the gallium oxide wafer covered with the amorphous gallium oxide film layer and place it at the center of another alumina boat. The distance between the sulfur powder and the gallium oxide wafer is about 15 cm. The evaporation temperature of the sulfur powder is about 200 °C. Heat the temperature at the gallium oxide wafer to 600 °C. Use a heating rate of 5 °C / min. Use nitrogen as the carrier gas with a constant flow rate of 50 sccm, and the holding time is 60 min. The patterned amorphous gallium oxide film layer reacts with sulfur vapor to obtain a two-dimensional gallium sulfide film layer. Thus, a heterojunction with a patterned gallium sulfide on the surface can be obtained.

[0091] Adopt a masking method to evaporate 100-nm-thick titanium metal on the gallium oxide wafer and the two-dimensional gallium sulfide film layer to construct a photodetector.

[0092] The element contents of the upper-layer two-dimensional gallium sulfide film layer and the lower-layer gallium oxide wafer obtained in this embodiment were both tested at two positions. The results show that the heterojunction obtained in this embodiment has a very high purity, and the lower-layer gallium oxide wafer was not sulfided. The results of the photoelectric detection response time detection show that the persistent photoconductivity effect of the photodetector constructed in this embodiment has been significantly suppressed.

[0093] Example 6: 1. Selection and treatment of raw materials 1.1. Take a large piece of solid metal gallium with a purity of 99.9999%. Under anaerobic conditions, preheat the hot stage in the glove box to 90 °C, and use the preheated hot stage to melt the metal gallium. Divide the melted metal gallium into 10 ml plastic bottles for subsequent use. Place the plastic bottles filled with metal gallium in a vacuum chamber and store them in a vacuum environment.

[0094] 1.2. Clean the gallium oxide crystal with persistent photoconductivity effect with water, acetone, and ethanol in sequence.

[0095] 1.3. Prepare a pre-designed mask plate in advance and mask the gallium oxide wafer. Use a methacrylic acid solution to perform patterned hydrophilic treatment on the masked gallium oxide wafer by spraying.

[0096] 2. Construction process of heterojunction 2.1. Place the glass sheet on a 100 °C hot stage, place the metal gallium on the glass sheet, and heat it through the hot stage to melt the metal gallium and make the liquid metal gallium in a flat state.

[0097] 2.2. Quickly scrape off the old gallium oxide on the surface of the liquid metal gallium in step 2.1 with glass to expose the fresh gallium droplets.

[0098] 2.3. Take off the mask plate on the surface of the gallium oxide wafer after the patterned hydrophilic treatment in step 1.3, then place it on a 40 °C hot stage for preheating, and quickly cover the surface of the gallium oxide wafer after the hydrophilic treatment on the surface of the fresh gallium droplets obtained in step 2.2 within 3 minutes, and then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after the hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the surface metal gallium with a cotton swab that does not shed cotton wool in boiling alcohol, and the force when the cotton swab contacts the gallium oxide amorphous thin film during cleaning is 1 N.

[0099] 2.4. Place 1 g of phosphoric acid powder on an alumina boat in the lower temperature region of a tube furnace. Invert a gallium oxide wafer covered with a patterned amorphous gallium oxide film layer and place it at the center of another alumina boat (i.e., the amorphous gallium oxide film layer is above the gallium oxide wafer). The distance between the gallium oxide wafer and the phosphoric acid powder is 12 cm. Nitrogen is used as the carrier gas with a flow rate of 0.6 L / min. The gallium oxide wafer and the phosphoric acid powder are heated at 300 °C for 90 min in the same temperature zone. The patterned amorphous gallium oxide film layer reacts with phosphorus vapor to obtain a two-dimensional GaPO4 film layer. Thus, a heterojunction with a patterned GaPO4 thin film covering the surface can be obtained.

[0100] By means of a mask, 100 nm of titanium metal is evaporated on both the gallium oxide wafer and the two-dimensional GaPO4 film layer to construct a photodetector.

[0101] The elemental contents of the upper two-dimensional GaPO4 film layer and the lower gallium oxide wafer obtained in this example were tested at two positions. The test results show that the heterojunction obtained in this example has a very high purity and the lower gallium oxide wafer was not phosphorylated. The results of the photoelectric detection response time detection show that the persistent photoconductivity effect of the photodetector constructed in this example was significantly inhibited.

[0102] Example 7: 1. Selection and treatment of raw materials 1.1. Take a large block of solid gallium with a purity of 99.9999%. Under anaerobic conditions, preheat the hot stage in the glove box to 100 °C, and use the preheated hot stage to melt the gallium metal. Divide the melted gallium metal into 10-ml plastic bottles for subsequent use. Place the filled plastic bottles containing gallium metal in a vacuum chamber and store them in a vacuum environment.

[0103] 1.2. Clean the gallium oxide wafer with persistent photoconductivity effect successively using water, acetone, and ethanol, with each solvent being used for cleaning 3 times.

[0104] 1.3. Prepare a pre-designed mask template in advance, mask the gallium oxide wafer, and perform a patterned hydrophilic treatment on the masked gallium oxide wafer by spraying with maleic anhydride solution.

[0105] 2. Construction process of the heterojunction 2.1. Place a glass slide on a 50 °C hot stage, place the gallium metal on the glass slide, and melt the gallium metal by heating with the hot stage to make the liquid gallium metal in a flat state.

[0106] 2.2. Quickly scrape the old gallium oxide on the surface of the liquid gallium metal in step 2.1 with a glass to expose the fresh gallium droplets.

[0107] 2.3. Remove the mask on the surface of the gallium oxide wafer after the patterned hydrophilic treatment in step 1.3, then place it on a hot stage at 40 °C for preheating, and quickly cover the surface of the gallium oxide wafer after the hydrophilic treatment onto the fresh gallium droplets obtained in step 2.2 within 3 minutes, and then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after the hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the residual metallic gallium with a cotton swab that does not shed cotton wool in boiling alcohol with a force of 1.5 N.

[0108] 2.4. Place 200 mg of urea on the alumina boat in the lower temperature region of the tube furnace. Invert the gallium oxide wafer covered with the patterned amorphous gallium oxide film layer and place it at the center of another alumina boat (i.e., the amorphous gallium oxide film layer is above the gallium oxide wafer). The distance between the two quartz boats is 10 cm. Heat the urea to 500 °C and heat the temperature at the gallium oxide wafer to 800 °C. The heating rate at both places is 10 °C / min, and use nitrogen gas with a flow rate of 50 sccm as the carrier gas. The holding time is 90 min for both, and after the synthesis, it is naturally cooled to room temperature. The patterned amorphous gallium oxide film layer reacts with ammonia gas to obtain a two-dimensional gallium nitride film layer.

[0109] By using a mask method, deposit a 100-nm-thick metallic titanium as an electrode on both the gallium oxide wafer and the two-dimensional gallium nitride film layer to construct a photodetector.

[0110] The element contents of the upper two-dimensional gallium nitride film layer and the lower gallium oxide wafer obtained in this example were both tested at two positions. The results show that the heterojunction obtained in this example has a very high purity, and the lower gallium oxide wafer is not nitrided. The results of the photodetection response time detection show that the persistent photoconductivity effect of the photodetector constructed in this example is significantly suppressed.

[0111] Example 8: 1. Selection and treatment of raw materials 1.1. Take a large piece of solid metallic gallium with a purity of 99.9999%. Under an oxygen-free condition, preheat the hot stage in the glove box to 100 °C, and melt the metallic gallium using the preheated hot stage. Divide the melted metallic gallium into 10-ml plastic bottles for subsequent use. Place the filled plastic bottles containing metallic gallium in a vacuum chamber and store them in a vacuum environment.

[0112] 1.2. Clean the gallium oxide thin film with persistent photoconductivity effect with water, acetone, and ethanol in sequence.

[0113] 1.3. Prepare a pre-designed mask in advance, mask the gallium oxide wafer, and perform a patterned hydrophilic treatment on the masked gallium oxide wafer using acrylic by evaporation.

[0114] 2. Fabrication Process of Heterojunction 2.1 Place the glass slide on a hot stage at 100 °C, put gallium metal on the glass slide, and heat it on the hot stage to melt the gallium metal so that the liquid gallium metal is in a flat state.

[0115] 2.2 Quickly scrape the old gallium oxide on the surface of the liquid gallium metal in step 2.1 with the glass to expose the fresh liquid gallium.

[0116] 2.3 Remove the mask on the surface of the gallium oxide wafer after the patterning hydrophilic treatment in step 1.3, then place it on a hot stage at 40 °C for preheating, and quickly cover the surface of the gallium oxide wafer after the hydrophilic treatment onto the surface of the fresh gallium droplets obtained in step 2.2 within 3 minutes, and then quickly remove the gallium oxide wafer within 10 seconds, so that the surface of the gallium oxide wafer after the hydrophilic treatment is covered with a patterned amorphous gallium oxide film layer. Clean the gallium oxide film with a cotton swab that does not shed cotton wool in boiling alcohol, and the force when the cotton swab contacts the amorphous gallium oxide film is 1 N.

[0117] 2.4 Place 100 mg of sulfur powder on the alumina boat in the lower temperature area of the tube furnace. Invert the gallium oxide sample covered with the amorphous gallium oxide film and place it in the center of another alumina boat. The distance between the sulfur powder and the gallium oxide wafer is about 12.5 cm. The evaporation temperature of the sulfur powder is about 250 °C. Heat the temperature at the gallium oxide wafer to 700 °C. Use a heating rate of 5 °C / min. Use nitrogen as the carrier gas with a constant flow rate of 50 sccm, and the holding time is 90 min. The patterned amorphous gallium oxide film layer reacts with sulfur vapor to obtain a two-dimensional gallium sulfide film layer. Thus, a heterojunction with a patterned gallium sulfide film layer on the surface can be obtained.

[0118] By using a masking method, deposit 100-nm-thick titanium metal on the gallium oxide wafer and the two-dimensional gallium sulfide film layer to construct a photodetector.

[0119] The element contents at two positions of the upper two-dimensional gallium sulfide film layer and the lower gallium oxide wafer obtained in this example were both tested. The results show that the purity of the heterojunction obtained in this example is very high, and the lower gallium oxide wafer was not sulfided. The results of the photoelectric detection response time detection show that the persistent photoconductivity effect of the photodetector constructed in this example was significantly inhibited.

[0120] Comparative Example 1 As described in Example 2, the difference is that: during the sulfidation process in step 2.4, the sulfur powder is 3 g, and the distance between the sulfur powder and the gallium oxide wafer is about 5 cm. The evaporation temperature of the sulfur powder is about 300 °C. Heat the temperature at the sample to 1100 °C. The holding time is 3 h.

[0121] Due to the excessively long heating time and too high temperature, the reaction will affect the gallium oxide wafer, making it impossible to obtain a heterojunction. The component content diagram of the heterojunction obtained in this comparative example is as Figure 6 shown. Comparative Example 2 As described in Example 6, the difference is that during the sulfurization process in Step 2.4, the distance between the gallium oxide wafer and the phosphoric acid powder is 20 cm, nitrogen is used as the carrier gas with a flow rate of 0.6 L / min, and the gallium oxide wafer and the phosphoric acid powder are heated at 200 °C for 30 min in the same temperature zone.

[0122] Due to the too short heating time and too low temperature, the upper amorphous gallium oxide film layer cannot be fully phosphated, so a heterojunction cannot be obtained. The obtained heterojunction has no obvious light response. The light response of this photodetector to light with a wavelength of 254 nm is as Figure 6 shown. Comparative Example 3 As described in Example 7, the difference is that the process of scraping off the old gallium oxide in Step 2.2 is not carried out.

[0123] At this time, the inherent gallium oxide layer on the surface shows a wrinkled and partially broken state, so a flat gallium oxide amorphous film layer cannot be obtained. The SEM diagram of the uppermost thin film obtained in this comparative example is as Figure 7 shown. Comparative Example 4 As described in Example 8, the difference is that the temperature at the gallium oxide wafer is heated to 300 °C and the holding time is 20 min.

[0124] Due to the too short reaction time available for sulfurization and the temperature not reaching the conversion temperature, it is impossible to prepare a heterojunction, and the persistent photoconductivity effect in the photodetector cannot be effectively suppressed.

[0125] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for suppressing the persistent photoconductivity effect of gallium oxide, characterized in that, It includes the following steps: Provide a gallium oxide crystal material and preheat the gallium oxide crystal material; the preheating temperature is not lower than the melting point of gallium metal; Under air conditions, spread liquid gallium oxide, and an amorphous gallium oxide film layer is formed on the surface of the spread liquid gallium oxide; Under the condition of keeping the liquid gallium oxide in a liquid state, contact the surface of the preheated gallium oxide crystal material with the amorphous gallium oxide film layer on the surface of the liquid gallium oxide, so that the amorphous gallium oxide film layer is transferred to the surface of the gallium oxide crystal material; Nitridize, phosphorylate or sulfidize the amorphous gallium oxide film layer on the surface of the gallium oxide crystal material, so that the amorphous gallium oxide film layer is converted into a gallium nitride film layer, a gallium phosphate film layer or a gallium sulfide film layer.

2. The method according to claim 1, characterized in that, Perform a hydrophilic treatment on the surface of the gallium oxide crystal material, and preheat the gallium oxide crystal material after the hydrophilic treatment.

3. The method according to claim 1, characterized in that, The material of the substrate for spreading the liquid gallium oxide is glass, quartz or a silicon wafer with an oxide layer.

4. The method according to claim 1, characterized in that, Keep the liquid gallium oxide in a liquid state by heating the substrate.

5. The method according to claim 1, characterized in that, Start preheating after the hydrophilic treatment of the surface of the gallium oxide crystal material, and within 3.0 min, contact the surface of the gallium oxide crystal material after the hydrophilic treatment with the amorphous gallium oxide film layer on the surface of the liquid gallium oxide.

6. The method according to claim 1, characterized in that, The contact time between the surface of the preheated gallium oxide crystal material and the amorphous gallium oxide film layer on the surface of the liquid gallium oxide is 0.01 - 10 s.

7. The method according to claim 1, characterized in that, After the transfer of the amorphous gallium oxide film layer, the residual gallium metal on the surface is cleaned in boiling ethanol.

8. The method according to claim 1, wherein The nitridation temperature is 600 - 900 °C, and the nitridation time is 30 - 120 min; Or, the nitrogen source used for nitridation is urea; Or, the sulfidation temperature is 500 - 800 °C, and the sulfidation time is 30 - 120 min; Or, the sulfur source used for sulfidation is sulfur; Or, the phosphorylation temperature is 300 - 600 °C, and the phosphorylation time is 60 - 120 min; Or, the phosphorus source used for phosphorylation is phosphoric acid.

9. Application of the method according to any one of claims 1 - 8 in the preparation of gallium oxide crystal-based optoelectronic devices.

10. The application according to claim 9, characterized in that, It also includes the process of preparing electrodes.

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