A method for preparing an erbium-doped gallium oxide film by mist chemical vapor deposition and applications thereof

Abstract

This invention discloses a method for preparing erbium-doped gallium oxide thin films via fog chemical vapor deposition and its applications. The method includes: preparing a solution containing gallium oxide and erbium precursors, adding a stabilizer; forming micron-sized droplets through ultrasonic or pneumatic atomization; depositing the film at a low temperature of 200-600℃ on substrates such as sapphire or silicon using nitrogen or argon as a carrier gas; and annealing to optimize crystal quality. The resulting thin films have an erbium doping concentration of 0.1-5 at.%, a thickness of 100-500 nm, a β-phase structure, a photoluminescence peak at 1.54 μm, a quantum yield of 12.0-20.1%, and a uniformity of 95-99%, making them suitable for fiber optic communication waveguide amplifiers and deep ultraviolet photodetectors. This method is low-temperature efficient, compatible with various substrates, reduces thermal stress, and significantly improves film quality and device performance.

Description

Technical Field

[0001] This invention relates to the technical field of erbium-doped gallium oxide thin films, and in particular to a fog chemical vapor deposition method for preparing erbium-doped gallium oxide thin films and its application. Background Technology

[0002] In recent years, with the rapid development of semiconductor materials science, gallium oxide (GaO), as an ultra-wide bandgap semiconductor material, has gradually become a research hotspot in the fields of power electronic devices, deep ultraviolet photodetectors, and optoelectronic integration. Its bandgap is approximately 4.8-5.3 eV, far exceeding that of traditional silicon-based and gallium nitride materials, endowing it with excellent breakdown field strength, high-temperature resistance, and radiation resistance. Since gallium oxide was first reported in the 1950s, the polymorphism of its crystal structure (including α, β, γ, δ, and ε phases) has provided ample space for the regulation of material properties. Among them, β-Ga2O3 is the most stable monoclinic phase and is commonly used for bulk material growth, such as melt growth techniques like flame melting, Czochralski method, and mode-guided method. These methods can prepare large-size single crystals, but are mainly limited to bulk applications. With the advancement of thin film epitaxy technology, vapor deposition methods such as pulsed laser deposition (PLD), metal-organic chemical vapor deposition (MOCVD), and molecular beam epitaxy (MBE) have been widely adopted for the preparation of high-quality Ga2O3 thin films. The development of these technologies stems from the need for device miniaturization and integration, such as achieving heteroepitaxial growth on sapphire or silicon substrates, further expanding the potential of Ga2O3 in solar blind zone detection and high-voltage switching devices. The introduction of rare-earth element doping, particularly erbium (Er) doping, marks the evolution of Ga2O3 materials from purely electronic to optoelectronic composite functions. 3+ The unique 4f electron shell transitions of ions can generate near-infrared emission (approximately 1.54 μm), which highly matches the wavelength of optical fiber communication. Therefore, Er-doped Ga₂O₃ films have been explored for use in waveguide amplifiers and electroluminescent devices. Early doping studies relied heavily on radio frequency magnetron sputtering or sol-gel methods. Subsequent studies combining PLD and MOCVD have enabled higher doping concentrations and control over crystal quality, driving the transition from basic material synthesis to practical device applications. However, these advances still depend on the uniform distribution of dopant elements and the compatibility of the host lattice to optimize photoelectric conversion efficiency and thermal stability.

[0003] Despite significant advancements in Ga2O3 thin film preparation and doping technologies, several limitations remain, particularly regarding the uniformity, preparation efficiency, and cost control of Er-doped gallium oxide films. While traditional MOCVD and MBE methods achieve atomic-level precision, they require high-temperature and high-vacuum environments, leading to high energy consumption and potential substrate thermal stress and interface defects, thus limiting their application on flexible or cryogenically compatible substrates. Furthermore, the volatility and stability of vapor precursors often result in uneven doping concentration gradients, affecting Er...3+ The activation efficiency and luminescence uniformity of ions are crucial factors. While PLD technology can deposit polycrystalline or amorphous thin films at room temperature, pulse energy fluctuations can easily lead to surface roughness and phase separation, especially with rare-earth doping, where the formation of Er atom clusters weakens the magnetic and optical properties of the material. Magnetron sputtering, though simple to operate, faces challenges such as complex sputtering target preparation and insufficient film density. The doping process easily introduces oxygen vacancy defects, thereby reducing carrier mobility and photoluminescence quantum yield. Sol-gel and other wet chemical methods, while low-cost, often cause film shrinkage and cracking during subsequent annealing, making it difficult to achieve large-area uniform deposition. Furthermore, the solubility of the dopant element is limited by the precursor ratio, making it difficult to precisely control the Er concentration to match specific wavelength luminescence requirements. These shortcomings manifest in practical applications as unstable device performance, poor fabrication repeatability, and obstacles to large-scale production. Especially when pursuing high-efficiency optical amplification and low-power integration, current methods struggle to balance low-temperature processing, doping uniformity, and economy, thus hindering the further promotion of Er-doped Ga2O3 thin films in fiber optic communication and optoelectronic sensors. Summary of the Invention

[0004] This application provides a method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition, including the following steps: (a) Preparation of precursor solution: Dissolve gallium oxide precursor and erbium precursor in solvent to form a homogeneous mixed solution, wherein the molar concentration of gallium oxide precursor is 0.01-0.5 mol / L and the molar concentration of erbium precursor is 0.1%-10% of the molar concentration of gallium oxide precursor. The solvent is selected from deionized water, ethanol, isopropanol or mixtures thereof, and stabilizers such as acetylacetone or citric acid may be added to enhance solution stability. (b) Atomization treatment: The precursor solution is atomized into micron-sized droplet atomized particles by an ultrasonic atomizer or a pneumatic atomizer, with the diameter controlled at 1-10 μm, the atomization power at 10-100 W, and the atomization temperature at room temperature to 80℃. (c) Transport and deposition: The atomized particles are transported to the reaction chamber by a carrier gas, which is selected from nitrogen, argon or air, with a flow rate of 0.5-5 L / min. The substrate temperature in the reaction chamber is controlled at 200-600℃, the deposition time is 10-120 minutes, and the chamber pressure is atmospheric pressure or low pressure (10-1000 Pa). (d) Post-treatment: After deposition, the film is annealed at a temperature of 400-800℃ for 0.5-2 hours in an oxygen or air atmosphere to improve crystal quality and activate erbium ions. The erbium doping concentration of the erbium-doped gallium oxide thin film is 0.1-5 at.%, the film thickness is 50-500 nm, and it has a β-phase crystal structure.

[0005] In a preferred embodiment of a fog chemical vapor deposition method for preparing erbium-doped gallium oxide thin films, the gallium oxide precursor is selected from gallium trichloride, gallium nitrate, gallium acetate, or organometallic compounds such as trimethylgallium; the erbium precursor is selected from erbium nitrate, erbium chloride, or erbium acetate.

[0006] In a preferred embodiment of a fog chemical vapor deposition method for preparing erbium-doped gallium oxide thin films, the substrate is selected from sapphire, silicon, gallium nitride, or glass substrates, and optionally undergoes pre-cleaning treatment, including ultrasonic cleaning and plasma etching, to improve film adhesion.

[0007] In a preferred embodiment of a fog chemical vapor deposition method for preparing erbium-doped gallium oxide thin films, in step (c), the reaction chamber is equipped with a heating system and a temperature gradient control device to ensure uniform pyrolysis and deposition of fog particles and avoid film defects caused by uneven temperature.

[0008] A preferred technical solution for a fog chemical vapor deposition method for preparing erbium-doped gallium oxide thin films includes, further comprising, introducing an auxiliary gas, such as oxygen or ozone, at a flow rate of 0.1-1 L / min during the deposition process to control the oxygen content and lattice integrity of the film.

[0009] As a preferred technical solution for the preparation of erbium-doped gallium oxide thin films by fog chemical vapor deposition, the method for preparing erbium-doped gallium oxide thin films is suitable for large-area deposition with a substrate size greater than 2 inches, and uniform coverage is achieved through a multi-nozzle fogging system.

[0010] In addition, this application discloses an erbium-doped gallium oxide thin film, which is prepared by the above method. The thin film has a uniform erbium ion distribution, a photoluminescence peak located near 1.54 μm, and a quantum yield greater than 10%, making it suitable for optical fiber communication devices.

[0011] Another application of erbium-doped gallium oxide thin films is to apply the above-prepared thin films to optoelectronic integrated devices, including waveguide amplifiers, electroluminescent devices, or deep ultraviolet photodetectors, wherein the thin film serves as an active layer, providing near-infrared emission and optical amplification functions.

[0012] As a preferred technical solution for the application of erbium-doped gallium oxide thin films, in a waveguide amplifier, the erbium-doped gallium oxide thin film is coupled to an optical fiber, with a pump wavelength of 980 nm or 1480 nm, to achieve amplification of the signal wavelength of 1.54 μm and a gain greater than 10 dB / cm.

[0013] The erbium-doped gallium oxide thin film preparation method provided by this invention has significant advantages over existing technologies. By combining optimized ultrasonic or pneumatic atomization processes with low-temperature deposition (200-600℃), this method achieves precisely controllable erbium doping concentration (0.1-5 at.%), uniform film thickness (100-500 nm), and low surface roughness (0.8-1.5 nm), ensuring the stability and high uniformity (95-99%) of the β-phase crystal structure. Adding stabilizers (such as acetylacetone or citric acid) significantly improves the stability of the precursor solution, avoids doping concentration gradients and film defects, achieves a quantum yield of 12.0-20.1%, and stabilizes the photoluminescence peak at 1.54 μm, making it particularly suitable for fiber optic communication waveguide amplifiers and electroluminescent devices. Low-temperature processing is compatible with various substrates (such as sapphire, silicon, and glass), reduces thermal stress and energy consumption, and achieves adhesion of 40-50 MPa. This method demonstrates significant advantages in preparation efficiency, cost control, and large-area deposition capability, providing a reliable technical guarantee for the large-scale application of erbium-doped gallium oxide thin films in optoelectronic integration and sensor fields. Detailed Implementation

[0014] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0015] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0016] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0017] Example Example 1 This embodiment provides a method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition, the specific steps of which are as follows: (a) Preparation of precursor solutions: Weigh 0.05 mol of gallium trichloride (GaCl3) as the gallium oxide precursor and 0.0025 mol of erbium nitrate (Er(NO3)3) as the erbium precursor. Slowly add both to 100 mL of deionized water while stirring to ensure complete dissolution and form a homogeneous mixed solution. The molar concentration of the gallium oxide precursor is 0.5 mol / L, and the molar concentration of the erbium precursor is 5% of the molar concentration of the gallium oxide precursor. To enhance solution stability, add 2 mL of acetylacetone as a stabilizer and continue stirring for 30 minutes until the solution is clear and free of precipitate.

[0018] (b) Atomization process: The above precursor solution was placed in an ultrasonic nebulizer, the atomization power was set to 50 W, and the atomization temperature was controlled at room temperature (25°C). The solution was atomized into micron-sized droplets with a diameter of about 5 μm by ultrasonic vibration to ensure uniform atomization and avoid the formation of large particles.

[0019] (c) Delivery and Deposition: The atomized particles were delivered to the reaction chamber using nitrogen as the carrier gas at a flow rate of 2 L / min. A sapphire substrate was used in the reaction chamber and pre-treated with ultrasonic cleaning (10 minutes each of alternating cleaning with ethanol and deionized water) and plasma etching (100 W power, 5 minutes) to improve adhesion. The substrate temperature was controlled at 400°C, the chamber pressure was maintained at atmospheric pressure (101.325 kPa), and the deposition time was 60 minutes. During this process, the atomized particles decomposed and deposited on the hot substrate surface to form a thin film.

[0020] (d) Post-treatment: After deposition, the film is placed in a tube furnace and annealed in an oxygen atmosphere at a temperature of 600°C for 1 hour to improve crystal quality, reduce defects and activate erbium ions.

[0021] Example 2 This embodiment provides a method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition. The difference from Embodiment 1 is that the precursor and fogging conditions are adjusted. The specific steps are as follows: (a) Preparation of precursor solutions: Weigh 0.01 mol of gallium nitrate (Ga(NO3)3) as the gallium oxide precursor and 0.00001 mol of erbium chloride (ErCl3) as the erbium precursor. Add both to 100 mL of a mixed solvent of ethanol and isopropanol (volume ratio 1:1), stir to dissolve, and form a homogeneous mixed solution, wherein the molar concentration of the gallium oxide precursor is 0.1 mol / L, and the molar concentration of the erbium precursor is 0.1% of the molar concentration of the gallium oxide precursor. Add 1 mL of citric acid as a stabilizer and stir for 45 minutes until the solution is stable.

[0022] (b) Atomization process: A pneumatic atomizer is used to atomize the precursor solution into droplet atomized particles with a diameter of about 2 μm. The atomization power is 20 W and the atomization temperature is 50℃ to ensure that the atomized particles are fine and uniform in order to improve the deposition efficiency.

[0023] (c) Delivery and Deposition: Argon gas was used as the carrier gas at a flow rate of 1 L / min to deliver the atomized particles to the reaction chamber. A silicon substrate was used, which underwent pre-cleaning treatment (ultrasonic cleaning for 15 minutes and plasma etching for 10 minutes). The substrate temperature was set at 300℃, the chamber pressure at 500 Pa, and the deposition time at 30 minutes. Oxygen was introduced as an auxiliary gas at a flow rate of 0.5 L / min to control the oxygen content of the thin film.

[0024] (d) Post-treatment: Annealing was carried out in an air atmosphere at a temperature of 500°C for 0.5 hours to promote lattice reconstruction and erbium ion activation.

[0025] Example 3 This embodiment provides a fog chemical vapor deposition method for preparing erbium-doped gallium oxide thin films, optimized for large-area deposition. The specific steps are as follows: (a) Preparation of precursor solutions: Weigh 0.03 mol of gallium acetate (Ga(CH3COO)3) as the gallium oxide precursor and 0.0015 mol of erbium acetate (Er(CH3COO)3) as the erbium precursor. Dissolve them in 200 mL of deionized water to form a mixed solution with molar concentrations of 0.15 mol / L and 5%, respectively. Add 3 mL of acetylacetone stabilizer and stir for 60 minutes until completely homogeneous.

[0026] (b) Atomization treatment: A multi-nozzle ultrasonic atomizer with a power of 80 W and a temperature of 70℃ is used to atomize the solution into particles with a diameter of 3-8 μm to ensure uniform atomization over a large area.

[0027] (c) Delivery and Deposition: Air was used as the carrier gas at a flow rate of 4 L / min and delivered to a reaction chamber equipped with a temperature gradient control device. The substrate was a gallium nitride substrate (4 inches), and pre-cleaning consisted of 20 minutes of ultrasonic cleaning and 15 minutes of plasma etching. The substrate temperature was 450°C, the chamber pressure was 200 Pa, and the deposition time was 90 minutes. Ozone-assisted gas was introduced at a flow rate of 0.8 L / min to enhance lattice integrity.

[0028] (d) Post-treatment: Annealing at 700℃ for 1.5 hours in an oxygen atmosphere.

[0029] Example 4 This embodiment provides a method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition and its application, focusing on low-temperature processing. The specific steps are as follows: (a) Preparation of precursor solutions: Weigh 0.02 mol of trimethylgallium (Ga(CH3)3) as the gallium oxide precursor and 0.002 mol of erbium nitrate as the erbium precursor. Dissolve them in 150 mL of ethanol to form a 0.13 mol / L, 10% solution. Add 2.5 mL of citric acid stabilizer and stir for 40 minutes.

[0030] (b) Atomization process: pneumatic atomizer, power 30 W, temperature 40℃, atomized particle diameter 1-5 μm.

[0031] (c) Delivery and deposition: Nitrogen carrier gas, flow rate 3 L / min; reaction chamber substrate is glass (pre-cleaning: ultrasonication for 10 minutes, plasma treatment for 5 minutes). Temperature 250℃, pressure 800 Pa, deposition time 120 minutes. Auxiliary gas oxygen, flow rate 0.3 L / min.

[0032] (d) Post-treatment: Annealing at 400°C for 2 hours in air.

[0033] Comparison Example Compare with Example 1 This comparative example provides a method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition. Compared with Example 1, only the addition of a stabilizer in the precursor solution is omitted; all other steps and parameters are the same. The specific steps are as follows: (a) Preparation of precursor solutions: Weigh 0.05 mol of gallium trichloride (GaCl3) as the gallium oxide precursor and 0.0025 mol of erbium nitrate (Er(NO3)3) as the erbium precursor. Slowly add both to 100 mL of deionized water while stirring to ensure complete dissolution and form a homogeneous mixture with a gallium oxide precursor molar concentration of 0.5 mol / L and an erbium precursor molar concentration of 5% of the gallium oxide precursor molar concentration. No stabilizers were added, and stirring continued for 30 minutes, but slight precipitation and instability occurred in the solution.

[0034] (b) Atomization process: The above precursor solution was placed in an ultrasonic nebulizer, the atomization power was set to 50 W, and the atomization temperature was controlled at room temperature (25°C). The solution was atomized into micron-sized droplets with a diameter of about 5 μm by ultrasonic vibration. However, due to the instability of the solution, the particle size was uneven during the atomization process.

[0035] (c) Transport and Deposition: Atomized particles were transported to the reaction chamber using nitrogen as the carrier gas at a flow rate of 2 L / min. A sapphire substrate was used in the reaction chamber and pre-treated with ultrasonic cleaning (10 minutes each of alternating cleaning with ethanol and deionized water) and plasma etching (100 W power, 5 minutes) to improve adhesion. The substrate temperature was controlled at 400°C, the chamber pressure was maintained at atmospheric pressure (101.325 kPa), and the deposition time was 60 minutes. During this process, the atomized particles decomposed and deposited on the hot substrate surface, but local aggregation of the film occurred due to particle inhomogeneity.

[0036] (d) Post-treatment: After deposition, the film was placed in a tube furnace and annealed in an oxygen atmosphere at a temperature of 600°C for 1 hour in an attempt to improve crystal quality and activate erbium ions, but the effect was limited.

[0037] Compare with Example 2 This comparative example provides a method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition. Compared with Example 1, only the substrate temperature is adjusted to 700°C, while the other steps and parameters are the same. The specific steps are as follows: (a) Preparation of precursor solutions: Weigh 0.05 mol of gallium trichloride (GaCl3) as the gallium oxide precursor and 0.0025 mol of erbium nitrate (Er(NO3)3) as the erbium precursor. Slowly add both to 100 mL of deionized water while stirring to ensure complete dissolution and form a homogeneous mixed solution. The molar concentration of the gallium oxide precursor is 0.5 mol / L, and the molar concentration of the erbium precursor is 5% of the molar concentration of the gallium oxide precursor. To enhance solution stability, add 2 mL of acetylacetone as a stabilizer and continue stirring for 30 minutes until the solution is clear and free of precipitate.

[0038] (b) Atomization process: The above precursor solution was placed in an ultrasonic nebulizer, the atomization power was set to 50 W, and the atomization temperature was controlled at room temperature (25°C). The solution was atomized into micron-sized droplets with a diameter of about 5 μm by ultrasonic vibration to ensure uniform atomization and avoid the formation of large particles.

[0039] (c) Delivery and Deposition: Atomized particles were delivered to the reaction chamber using nitrogen as the carrier gas at a flow rate of 2 L / min. A sapphire substrate was used in the reaction chamber and pre-treated with ultrasonic cleaning (10 minutes each of alternating cleaning with ethanol and deionized water) and plasma etching (100 W power, 5 minutes) to improve adhesion. The substrate temperature was controlled at 700°C, the chamber pressure was maintained at atmospheric pressure (101.325 kPa), and the deposition time was 60 minutes. During this process, the atomized particles decomposed and deposited on the hot substrate surface, but the high temperature led to increased thermal stress and interface defects.

[0040] (d) Post-treatment: After deposition, the film was placed in a tube furnace and annealed in an oxygen atmosphere at a temperature of 600°C for 1 hour to improve crystal quality and activate erbium ions. However, the high-temperature deposition introduced irreversible defects.

[0041] Table 1

[0042] Analysis of the table data shows that the erbium-doped gallium oxide thin film fog chemical vapor deposition method provided by this invention exhibits excellent performance consistency in Examples 1 to 4. The erbium doping concentration can be precisely controlled within the range of 0.1-5 at.%, the film thickness is stable at 100-500 nm, all showing a pure β-phase crystal structure, the photoluminescence peak is consistently located at 1.54 μm, the quantum yield is as high as 12.0-20.1%, the surface roughness is as low as 0.8-1.5 nm, the uniformity reaches 95-99%, and the adhesion is as strong as 40-50 MPa, demonstrating its applicability to low-temperature processing and large-area deposition. In contrast, Control Example 1, due to the omission of the stabilizer, resulted in uneven film thickness (150-250 nm), uneven grain size, a decrease in quantum yield of approximately 30% to 12.95%, an increase in surface roughness to 3.5 nm, a decrease in uniformity to 70%, and an adhesion of only 30 MPa. MPa highlights the crucial role of stabilizers in solution stability and film quality. In contrast, Example 2, while maintaining doping concentration and thickness by increasing the substrate temperature to 700°C, introduced phase separation defects, resulting in a 25% decrease in quantum yield to 13.875%, an increase in surface roughness to 2.8 nm, a uniformity of 85%, and an adhesion of 35 MPa. This demonstrates the significant advantage of controlling the moderate temperature (200-600°C) in this method in avoiding thermal stress and defects, thus comprehensively verifying the beneficial effects of this preparation process in improving the optical and electrical properties of thin films and device applicability.

[0043] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing erbium-doped gallium oxide thin films by fog chemical vapor deposition, characterized in that, Includes the following steps: (a) Preparation of precursor solution: Dissolve gallium oxide precursor and erbium precursor in solvent to form a homogeneous mixed solution, wherein the molar concentration of gallium oxide precursor is 0.01-0.5 mol / L and the molar concentration of erbium precursor is 0.1%-10% of the molar concentration of gallium oxide precursor. The solvent is selected from deionized water, ethanol, isopropanol or mixtures thereof, and stabilizers such as acetylacetone or citric acid may be added to enhance solution stability. (b) Atomization treatment: The precursor solution is atomized into micron-sized droplet atomized particles by an ultrasonic atomizer or a pneumatic atomizer, with the diameter controlled at 1-10 μm, the atomization power at 10-100 W, and the atomization temperature at room temperature to 80℃. (c) Transport and deposition: The atomized particles are transported to the reaction chamber by a carrier gas, which is selected from nitrogen, argon or air, with a flow rate of 0.5-5 L / min. The substrate temperature in the reaction chamber is controlled at 200-600℃, and the deposition time is 10-120 minutes. (d) Post-treatment: After deposition, the film is annealed at a temperature of 400-800℃ for 0.5-2 hours in an oxygen or air atmosphere to improve crystal quality and activate erbium ions. The erbium doping concentration of the erbium-doped gallium oxide thin film is 0.1-5 at.%, the film thickness is 50-500 nm, and it has a β-phase crystal structure.

2. The method according to claim 1, characterized in that, The gallium oxide precursor is selected from gallium trichloride, gallium nitrate, gallium acetate, or organometallic compounds such as trimethylgallium; the erbium precursor is selected from erbium nitrate, erbium chloride, or erbium acetate.

3. The method according to claim 1, characterized in that, The substrate is selected from sapphire, silicon, gallium nitride, or glass substrates, and may optionally undergo pre-cleaning treatment, including ultrasonic cleaning and plasma etching.

4. The method according to claim 1, characterized in that, In step (c), the reaction chamber is equipped with a heating system and a temperature gradient control device.

5. The method according to claim 1, characterized in that, The method further includes introducing an auxiliary gas, such as oxygen or ozone, during the deposition process at a flow rate of 0.1-1 L / min.

6. The method according to claim 1, characterized in that, The method for preparing the erbium-doped gallium oxide thin film is suitable for large-area deposition with a substrate size greater than 2 inches.

7. An erbium-doped gallium oxide thin film, characterized in that, The film is prepared by any one of claims 1-6, and has a uniform erbium ion distribution, a photoluminescence peak located near 1.54 μm, and a quantum yield greater than 10%.

8. An application of an erbium-doped gallium oxide thin film, characterized in that, The thin film of claim 7 is applied to optoelectronic integrated devices, including waveguide amplifiers, electroluminescent devices, or deep ultraviolet photodetectors, wherein the thin film serves as an active layer, providing near-infrared emission and light amplification functions.

9. The application according to claim 8, characterized in that, In the waveguide amplifier, the erbium-doped gallium oxide thin film is coupled to an optical fiber, with a pump wavelength of 980 nm or 1480 nm, to achieve amplification of the signal wavelength of 1.54 μm and a gain greater than 10 dB / cm.

Images