Gallium oxide thin film and heterojunction preparation device and method thereof

Abstract

The invention relates to the field of material preparation, in particular to a gallium oxide thin film and heterojunction preparation device and method.The gallium oxide thin film heterojunction preparation device comprises vacuum coating equipment of a cavity structure, a source material evaporation source, a heatable substrate, a laser source and an air inlet, and the source material evaporation source is arranged at the bottom of the vacuum coating equipment; the heatable substrate is arranged at the top of the vacuum coating equipment, the laser source is arranged on one side of the vacuum coating equipment, and the air inlet is formed in the other side of the vacuum coating equipment. The gallium oxide thin film and the heterojunction thereof are prepared in situ in the same device, the functions of semiconductor doping, laser-induced recrystallization, interface state regulation and control, semiconductor annealing treatment and the like are realized, and the electrical characteristics and crystal structures of the gallium oxide thin film and the heterojunction thereof are regulated in situ. Therefore, the low-cost and high-quality gallium oxide thin film and the heterojunction thereof are prepared.

Description

Technical Field

[0001] The present invention relates to the field of material preparation, and more specifically, to a gallium oxide thin film and a heterojunction preparation device and method thereof. Background Art

[0002] Solar-blind ultraviolet detectors play a vital role in many high-tech fields due to their unique spectral response characteristics. In space exploration, they can accurately detect solar-blind ultraviolet radiation from distant galaxies, providing scientists with valuable cosmic information; in military equipment, solar-blind ultraviolet detectors can be used for covert communications and precise navigation of guidance systems, greatly improving the concealment and accuracy of military operations; in the field of radiation monitoring, they can monitor the radiation level around nuclear facilities in real time to ensure public safety; in ultraviolet lithography technology, solar-blind ultraviolet detectors can be used to accurately control the lithography process and improve the manufacturing accuracy of semiconductor devices; in addition, in the field of scientific research, solar-blind ultraviolet detectors have become an important tool for exploring the microstructure and properties of matter.

[0003] Gallium oxide, as a semiconductor material with excellent optoelectronic properties, has become an ideal material for preparing solar-blind ultraviolet detectors because of its bandgap width of about 4.9eV, and the corresponding light absorption wavelength falls exactly in the solar-blind ultraviolet region. However, despite the excellent performance of gallium oxide, the preparation of its single crystal film faces the problem of complex technology and high cost. The traditional single crystal gallium oxide film preparation process often requires high-precision equipment and complex operating procedures, which not only increases the production cost, but also limits the possibility of its large-scale application.

[0004] In order to break through this technical bottleneck, researchers began to explore simpler and more economical preparation processes. Among them, the vacuum deposition process is favored because of its simple operation and low cost. Through vacuum deposition technology, researchers successfully prepared amorphous gallium oxide thin films. Although amorphous films may be slightly inferior to single crystal films in some properties, the significant reduction in preparation cost and simplification of the preparation process make amorphous gallium oxide films still have broad application prospects in the field of solar-blind ultraviolet detectors.

[0005] However, relying solely on amorphous gallium oxide films is not enough to meet the needs of high-performance solar-blind ultraviolet detectors. In order to achieve low dark current, high charge collection efficiency, high sensitivity and fast response characteristics, researchers have begun to turn their attention to gallium oxide heterojunction detectors. By constructing a heterojunction of gallium oxide and other semiconductor materials, the performance of the detector can be further optimized. However, the interface state of the gallium oxide heterojunction has become a key issue that needs to be solved urgently. The existence of the interface state will seriously affect the photoelectric response characteristics of the detector, leading to problems such as increased dark current and reduced response speed. Therefore, how to effectively regulate the interface state of the gallium oxide heterojunction to improve the comprehensive performance of the detector has become a research hotspot and difficulty in this field. Summary of the invention

[0006] In order to overcome at least one of the defects of the prior art, the present invention provides a device and method for preparing a gallium oxide thin film and a heterojunction thereof.

[0007] The present invention aims to solve the above technical problems at least to a certain extent.

[0008] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0009] A gallium oxide thin film and a heterojunction preparation device thereof, comprising: a vacuum coating device with a cavity structure inside, a source material evaporation source, a heatable substrate, a laser source and an air inlet, wherein the source material evaporation source is arranged at the bottom of the vacuum coating device, the top of the source material evaporation source is arranged with a heatable substrate, the lower surface of the heatable substrate is arranged with a substrate, and the laser source and the air inlet are both arranged on the vacuum coating device.

[0010] Furthermore, the source material evaporation source includes at least three crucibles, and semiconductor particles are arranged in the crucibles.

[0011] Furthermore, the semiconductor particles include: any one of gallium oxide particles doped with a preset element, P-type semiconductor particles or N-type semiconductor particles.

[0012] Furthermore, the preset element-doped gallium oxide particles include Ga2O3 doped with one or more combinations of SiO2, MgO, NiO, ZnO, TiO2, In2O3, SnO2 and MnO.

[0013] Furthermore, the material of the substrate is any one of silicon wafer, quartz, glass, ceramic and stainless steel.

[0014] Furthermore, the laser source is a structure with adjustable rotation angle, laser wavelength and optical power density.

[0015] Furthermore, the orientation of the laser source and the evaporation direction of the source material evaporation source are both capable of heating the substrate surface.

[0016] A method for preparing a gallium oxide thin film and a heterojunction thereof, which is applied to the gallium oxide thin film and a heterojunction preparation device, comprises the following steps:

[0017] S1: Fix the substrate on the lower surface of the heatable base plate, and evacuate the inside of the vacuum coating equipment to a vacuum state through the air inlet;

[0018] S2: evaporating P-type semiconductor particles of the source material evaporation source to deposit a P-type semiconductor film on the surface of the substrate;

[0019] S3: the gas inlet delivers a preset gas to the surface of the P-type semiconductor film, and uses a laser source to perform laser irradiation treatment on the surface of the P-type semiconductor film;

[0020] S4: evaporating gallium oxide particles doped with a preset element of a source material evaporation source, and depositing a gallium oxide film on the surface of the P-type semiconductor film;

[0021] S5: the gas inlet delivers a preset gas to the surface of the gallium oxide film, and uses a laser source to perform laser irradiation treatment on the surface of the gallium oxide film;

[0022] S6: evaporating N-type semiconductor particles of a source material evaporation source to deposit an N-type semiconductor film on the surface of the gallium oxide film;

[0023] S7: The gas inlet delivers a preset gas to the surface of the N-type semiconductor film, and uses a laser source (5) to perform laser irradiation treatment on the surface of the N-type semiconductor film to obtain a gallium oxide film and a heterojunction thereof.

[0024] Furthermore, after step S7, the method further includes performing a high temperature annealing treatment on the obtained gallium oxide film and its heterojunction, including:

[0025] The heatable substrate is heated to a preset temperature, and a high-temperature annealing treatment is performed on the obtained gallium oxide film and the heterojunction thereof.

[0026] Furthermore, the air intake flow rate of the air intake port ranges from 0.2 to 40 SCCM.

[0027] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0028] The source material evaporation source is arranged at the bottom of the vacuum coating equipment, the heatable substrate is arranged on the top of the source material evaporation source, the laser source is arranged on one side of the vacuum coating equipment, the air inlet is arranged on the other side of the vacuum coating equipment, and the gallium oxide film is arranged on the surface of the heatable substrate. The present invention in-situ prepares the gallium oxide film and its heterojunction, semiconductor doping, laser-induced recrystallization, interface state regulation and semiconductor annealing treatment in the same device, reduces the material preparation cost, and in-situ regulates the electrical properties and crystal structure of the gallium oxide film and its heterojunction, thereby preparing high-quality gallium oxide film and its heterojunction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the device for preparing the gallium oxide thin film and its heterojunction according to the present invention;

[0030] Figure 2 This is a schematic diagram of the structure of the device for preparing the gallium oxide thin film and its heterojunction according to this embodiment;

[0031] Figure 3 It is a schematic diagram of the process of preparing the gallium oxide thin film and its heterojunction according to the present invention;

[0032] Figure 4 This is a schematic diagram of the process of preparing the gallium oxide thin film and its heterojunction according to this embodiment;

[0033] Figure 5 This is a surface morphology image of the gallium oxide film described in this embodiment;

[0034] In the attached figure: 1. vacuum coating equipment; 2. source material evaporation source; 3. source material vapor flow; 4. heatable substrate; 5. laser source; 6. laser; 7. air inlet; 8. substrate; 9. gallium oxide film and its heterojunction; 10. P-type semiconductor film; 11. silicon-doped gallium oxide film; 12. N-type semiconductor film. DETAILED DESCRIPTION

[0035] The drawings are for illustrative purposes only and should not be construed as limiting the present patent;

[0036] In order to better illustrate the present embodiment, some parts in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product;

[0037] It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0038] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0039] Example 1

[0040] A gallium oxide thin film and a heterojunction preparation device thereof, such as Figure 1 As shown, it includes: a vacuum coating device 1 with a cavity structure inside, a source material evaporation source 2, a heatable substrate 4, a laser source 5 and an air inlet 7, wherein the source material evaporation source 2 is arranged at the bottom of the vacuum coating device 1, the top of the source material evaporation source 2 is provided with a heatable substrate 4, the lower surface of the heatable substrate 4 is provided with a substrate 8, and the laser source 5 and the air inlet 7 are both arranged on the vacuum coating device 1.

[0041] In a specific implementation process, the source material evaporation source is arranged at the bottom of the vacuum coating equipment, the heatable substrate is arranged on the top of the source material evaporation source, the laser source is arranged on one side of the vacuum coating equipment, the air inlet is arranged on the other side of the vacuum coating equipment, and the gallium oxide film is arranged on the surface of the heatable substrate. The present invention in-situ prepares the gallium oxide film and its heterojunction, semiconductor doping, laser-induced recrystallization, interface state regulation and semiconductor annealing treatment in the same device, reduces the material preparation cost, and in-situ regulates the electrical properties and crystal structure of the gallium oxide film and its heterojunction, thereby preparing high-quality gallium oxide film and its heterojunction.

[0042] Example 2

[0043] This embodiment further discloses the following contents based on the embodiment 1:

[0044] The source material evaporation source 2 includes at least three crucibles, in which semiconductor particles are arranged, and the source material can be melted and evaporated within a specific time.

[0045] In the specific implementation process, the source materials are P-type semiconductor particles, N-type semiconductor particles and silicon-doped gallium oxide particles. The source material evaporation source consists of 5 crucibles, and each crucible is filled with a source material, and the source material can be melted and evaporated within a specific time. The gallium oxide film and its heterojunction preparation and semiconductor doping process are realized in situ on the same equipment.

[0046] Example 3

[0047] This embodiment further discloses the following contents based on Embodiments 1 and 2:

[0048] The semiconductor particles include: any one of gallium oxide particles doped with a preset element, P-type semiconductor particles or N-type semiconductor particles.

[0049] The gallium oxide particles doped with the preset elements include Ga2O3 doped with one or more combinations of SiO2, MgO, NiO, ZnO, TiO2, In2O3, SnO2 and MnO.

[0050] The substrate is one of silicon wafer, quartz, glass, ceramic and stainless steel.

[0051] Example 4

[0052] This embodiment further discloses the following contents based on Embodiments 1, 2 and 3:

[0053] The laser source 5 is a structure with adjustable rotation angle, laser wavelength and optical power density.

[0054] The laser source has a laser wavelength range of 200 to 1500 nm and an optical power density range of 0.1 to 150 mW / cm 2 , the laser light from the laser source can be accurately irradiated at any position on the heatable substrate.

[0055] Semiconductor films undergo recrystallization under laser irradiation to achieve polycrystalline or single-crystal semiconductor films; on the other hand, laser irradiation can remove the interface state of the semiconductor film and prepare a gallium oxide film heterojunction with low interface state density. Gallium oxide film and its heterojunction preparation, laser-induced recrystallization, and interface state regulation can be achieved in situ on the same device.

[0056] The orientation of the laser source 5 and the evaporation direction of the source material evaporation source 2 are both capable of heating the surface of the substrate 4 .

[0057] Example 5

[0058] This embodiment, based on Embodiments 1, 2, 3 and 4, continues to disclose the following contents:

[0059] A method for preparing a gallium oxide thin film and a heterojunction thereof, which is applied to the gallium oxide thin film and a heterojunction preparation device, comprises the following steps:

[0060] S1: fix the substrate 8 to the lower surface of the heatable base plate 4, and evacuate the interior of the vacuum coating device 1 to a vacuum state through the air inlet 7;

[0061] S2: evaporating the P-type semiconductor particles of the source material evaporation source 2 to deposit a P-type semiconductor thin film on the surface of the substrate 8;

[0062] S3: the gas inlet 7 delivers a preset gas to the surface of the P-type semiconductor film, and the laser source 5 performs laser irradiation treatment on the surface of the P-type semiconductor film;

[0063] S4: evaporating gallium oxide particles doped with a preset element from the source material evaporation source 2 to deposit a gallium oxide film on the surface of the P-type semiconductor film;

[0064] S5: the gas inlet 7 delivers a preset gas to the surface of the gallium oxide film, and the laser source 5 performs laser irradiation treatment on the surface of the gallium oxide film;

[0065] S6: evaporating N-type semiconductor particles of the source material evaporation source 2 to deposit an N-type semiconductor film on the surface of the gallium oxide film;

[0066] S7: The gas inlet 7 delivers a preset gas to the surface of the N-type semiconductor film, and the laser source 5 is used to perform laser irradiation treatment on the surface of the N-type semiconductor film to obtain a gallium oxide film and a heterojunction thereof.

[0067] In a specific implementation process, the raw materials include: gallium oxide particles doped with specific elements, the specific elements include Si, Mg, Ni, Zn, Ti, In, Sn and Mn, etc., the gallium oxide doped with specific elements is composed of Ga2O3 and one or more doping element oxides, the doping element oxides include SiO2, MgO, NiO, ZnO, TiO2, In2O3, SnO2 and MnO, etc., and the mass content of the doping element oxides ranges from 1% to 60%;

[0068] P-type semiconductor particles, wherein the P-type semiconductor includes any one of P-type NiO, Cu2O, CoO, Cu2S, SnO, SnS and MnO semiconductors;

[0069] N-type semiconductor particles, wherein the N-type semiconductor includes any one of N-type WO3, TiO2, Fe2O3, ZnO, V2O5, CrO3 and BaO semiconductors.

[0070] The air flow rate range of the air inlet 7 is 0.2-40 SCCM, and the gas transported by the air inlet includes oxygen, ozone, nitrogen, argon and hydrogen.

[0071] Example 6

[0072] This embodiment, based on Embodiments 1, 2, 3, 4 and 5, continues to disclose the following contents:

[0073] After step S7, the method further includes performing high temperature annealing treatment on the obtained gallium oxide film and its heterojunction, including:

[0074] The heatable substrate 4 is heated to a preset temperature, and a high temperature annealing treatment is performed on the obtained gallium oxide thin film and its heterojunction.

[0075] The heating temperature range of the heatable substrate is 50 to 1200° C. The heatable substrate is a circular substrate with a diameter of 5 to 30 inches, and semiconductor annealing processing can be achieved in situ on the same equipment.

[0076] Example 7

[0077] This embodiment, based on Embodiments 1, 2, 3, 4, 5 and 6, continues to disclose the following contents:

[0078] like Figure 2 As shown in the figure, step 1: use quartz glass as a substrate with an area of ​​2 cm × 2 cm and a thickness of 1 mm. Use acetone, anhydrous ethanol and water to ultrasonically clean the quartz glass substrate in sequence for 15 min. Fix the quartz glass substrate on a heatable substrate and pump the vacuum degree of the electron beam evaporation equipment chamber to 3 × 10 -3 Pa.

[0079] Step 2: evaporate the P-type semiconductor particles of the source material evaporation source and deposit a layer of P-type semiconductor film on the surface of the substrate. The P-type semiconductor is NiO, the deposition rate is 0.05nm / s, and the deposition thickness is 200nm.

[0080] Step 3: Ozone is delivered to the surface of the NiO film through the air inlet, and the surface of the NiO film is irradiated with a laser source. The ozone flow rate is 6 SCCM, the laser wavelength is 550 nm, and the optical power density is 20 mW / cm 2 , the irradiation time is 10min.

[0081] Step 4: Evaporating the silicon-doped gallium oxide particles of the source material evaporation source and depositing a layer of silicon-doped gallium oxide film on the surface of the NiO film. The silicon-doped gallium oxide particles are composed of gallium oxide and silicon dioxide, and the mass content of silicon dioxide is 30%. The deposition rate of the silicon-doped gallium oxide film is 0.1 nm / s, and the deposition thickness is 800 nm.

[0082] Step 5: Ozone is delivered to the surface of the gallium oxide film through the air inlet, and the surface of the gallium oxide film is irradiated with laser using a laser source. The ozone flow rate is 10 SCCM, the laser wavelength is 550 nm, and the optical power density is 30 mW / cm 2 , the irradiation time is 30min.

[0083] Step 6: Evaporate the N-type semiconductor particles of the source material evaporation source and deposit a layer of N-type semiconductor film on the surface of the gallium oxide film. The N-type semiconductor is ZnO, the deposition rate is 0.05nm / s, and the deposition thickness is 200nm.

[0084] Step 7: Ozone is delivered to the surface of the ZnO film through the air inlet, and the surface of the ZnO film is irradiated with laser using a laser source. The ozone flow rate is 6 SCCM, the laser wavelength is 550 nm, and the optical power density is 20 mW / cm 2 , the irradiation time is 10min.

[0085] Step 8: Heat the heatable substrate to 500° C. and anneal the prepared gallium oxide heterojunction for 1 hour.

[0086] In the specific implementation process, the above-mentioned preparation process can realize in-situ preparation of gallium oxide thin film and its heterojunction, semiconductor doping, laser-induced recrystallization, interface state regulation and semiconductor annealing treatment on the same equipment, and in-situ regulate the electrical properties and crystal structure of the gallium oxide thin film and its heterojunction, thereby preparing high-quality gallium oxide thin film and its heterojunction. Figure 5 This is a surface morphology image of a gallium oxide film prepared using the above scheme.

[0087] Example 8

[0088] This embodiment, based on Embodiments 1, 2, 3, 4, 5, 6 and 7, continues to disclose the following contents:

[0089] In the process of this embodiment, in steps 3 to 7, during the deposition of NiO thin film, gallium oxide thin film and ZnO thin film, oxygen is delivered to the thin film deposition site of the sample and laser irradiation is performed. The oxygen flow rate is 8 SCCM, the laser wavelength is 550 nm, and the optical power density is 15 mW / cm 2 Through this embodiment, the crystallinity of the gallium oxide thin film and the heterojunction is further improved.

[0090] The same or similar reference numerals correspond to the same or similar components;

[0091] The terms used in the drawings to describe positional relationships are only used for illustrative purposes and should not be construed as limiting this patent;

[0092] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A gallium oxide thin film and a heterojunction preparation device thereof, characterized in that: include: A vacuum coating device (1) having a cavity structure inside, a source material evaporation source (2), a heatable substrate (4), a laser source (5) and an air inlet (7), wherein the source material evaporation source (2) is arranged at the bottom of the vacuum coating device (1), a heatable substrate (4) is arranged on the top of the source material evaporation source (2), a substrate (8) is arranged on the lower surface of the heatable substrate (4), and the laser source (5) and the air inlet (7) are both arranged on the vacuum coating device (1).

2. A gallium oxide thin film and a heterojunction preparation device according to claim 1, characterized in that: The source material evaporation source (2) comprises at least three crucibles, wherein semiconductor particles are arranged in the crucibles.

3. A gallium oxide thin film and a heterojunction preparation device according to claim 2, characterized in that: The semiconductor particles include: any one of gallium oxide particles doped with a preset element, P-type semiconductor particles or N-type semiconductor particles.

4. A gallium oxide thin film and a heterojunction preparation device according to claim 3, characterized in that: The gallium oxide particles doped with the preset elements include Ga2O3 doped with one or more combinations of SiO2, MgO, NiO, ZnO, TiO2, In2O3, SnO2 and MnO.

5. The gallium oxide thin film and heterojunction preparation device according to claim 1, characterized in that: The material of the substrate (8) is any one of silicon wafer, quartz, glass, ceramic and stainless steel.

6. The gallium oxide thin film and heterojunction preparation device according to claim 1, characterized in that: The laser source (5) is a structure with adjustable rotation angle, laser wavelength and optical power density.

7. A gallium oxide thin film and a heterojunction preparation device according to claim 6, characterized in that: The orientation of the laser source (5) and the evaporation direction of the source material evaporation source (2) are both capable of heating the surface of the substrate (4).

8. A gallium oxide thin film and a method for preparing a heterojunction thereof, characterized in that: The device for preparing the gallium oxide thin film and its heterojunction as claimed in any one of claims 1 to 7 comprises the following steps: S1: fixing the substrate (8) on the lower surface of the heatable base plate (4), and evacuating the interior of the vacuum coating device (1) to a vacuum state through the air inlet (7); S2: evaporating P-type semiconductor particles of the source material evaporation source (2) to deposit a P-type semiconductor thin film on the surface of the substrate (8); S3: the gas inlet (7) delivers a preset gas to the surface of the P-type semiconductor film, and the laser source (5) is used to perform laser irradiation treatment on the surface of the P-type semiconductor film; S4: evaporating gallium oxide particles doped with a preset element from a source material evaporation source (2) to deposit a gallium oxide film on the surface of the P-type semiconductor film; S5: the gas inlet (7) delivers a preset gas to the surface of the gallium oxide film, and the laser source (5) is used to perform laser irradiation treatment on the surface of the gallium oxide film; S6: evaporating N-type semiconductor particles of the source material evaporation source (2) to deposit an N-type semiconductor film on the surface of the gallium oxide film; S7: The gas inlet (7) delivers a preset gas to the surface of the N-type semiconductor film, and the laser source (5) is used to perform laser irradiation treatment on the surface of the N-type semiconductor film to obtain a gallium oxide film and a heterojunction thereof.

9. The method for preparing the gallium oxide thin film and its heterojunction according to claim 8, characterized in that: After step S7, the method further includes performing high temperature annealing treatment on the obtained gallium oxide film and its heterojunction, including: The heatable substrate (4) is heated to a preset temperature to perform high temperature annealing on the obtained gallium oxide thin film and its heterojunction.

10. The method for preparing the gallium oxide thin film and its heterojunction according to claim 8, characterized in that: The air intake flow rate of the air intake port (7) ranges from 0.2 to 40 SCCM.

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