Method for selective defect manipulation by ion implantation

Abstract

The application provides a method for controlling selected defects under ion implantation, and relates to the technical field of semiconductor preparation. The method comprises the following steps: S1, providing a gallium nitride substrate, preparing a patterned mask on the surface of the gallium nitride substrate, and selecting at least two target regions on the gallium nitride substrate, wherein the gallium nitride substrate has the same defect density in the at least two target regions; S2, respectively implanting ions into the at least two target regions through the patterned mask under different implantation conditions, so that the gallium nitride substrate has defect densities corresponding to the different implantation conditions in the at least two target regions; wherein the different implantation conditions include at least one difference in the following aspects: ion species, implantation dose, implantation energy and implantation angle.

Description

Technical Field

[0001] This invention relates to the field of semiconductor fabrication technology, and in particular to a method for selective defect control under ion implantation. Background Technology

[0002] Gallium nitride (GaN), a representative of third-generation semiconductor materials, has shown enormous application potential in high-voltage, high-frequency, high-power, and optoelectronic devices. Achieving high-performance p-type doping is one of the key technologies for fabricating GaN-based devices and optoelectronic devices. Currently, ion implantation is one of the mainstream methods for introducing dopant ions to modulate the electrical properties of materials.

[0003] However, existing ion implantation techniques typically employ a uniform dose, global implantation approach. While this introduces dopants, it also results in significant lattice damage, introducing numerous point and extended defects. For example, this ion implantation mode lacks spatial selectivity, making it difficult to differentiate defect and doping control for different functional regions within the device. Furthermore, the defect control capability is coarse; the resulting defects are of mixed types and diffusely distributed, hindering precise carrier control and potentially becoming leakage paths or weak points in device reliability. In addition, this approach struggles to achieve effective electrical isolation. Device fabrication often requires the formation of high-resistivity isolation regions in specific areas through ion implantation. Current techniques typically employ extremely high-dose uniform implantation to induce material amorphization, but this leads to severe difficulties in lattice recovery and low impurity activation rates, thus impacting the performance and yield of GaN-based devices. Summary of the Invention

[0004] In view of the above problems, the present invention provides a selective defect control method under ion implantation. By combining patterned masks and ion implantation under different implantation conditions, the defect density can be quantitatively controlled on the same gallium nitride substrate, solving the problems of inaccurate defect control and poor selectivity in existing in-situ doping and other technologies.

[0005] This invention provides a method for selective defect control under ion implantation, comprising: step S1, providing a gallium nitride substrate and preparing a patterned mask on the surface of the gallium nitride substrate to select at least two target regions on the gallium nitride substrate, wherein the gallium nitride substrate has the same defect density in the at least two target regions; step S2, performing ion implantation on the at least two target regions under different implantation conditions through the patterned mask, so that the gallium nitride substrate has a defect density corresponding to the different implantation conditions in the at least two target regions; wherein the different implantation conditions include at least one of implanted ion type, implantation dose, implantation energy and implantation angle being different.

[0006] According to an embodiment of the present invention, the patterned mask is prepared by performing at least two patterning processes in sequence.

[0007] According to an embodiment of the present invention, the patterning process includes: depositing a mask material layer on the surface of a gallium nitride substrate; forming a photoresist pattern on the mask material layer; and etching the mask material layer with the photoresist pattern as a reference.

[0008] According to an embodiment of the present invention, the patterning process includes: forming a photoresist layer on the surface of a gallium nitride substrate; and exposing and developing the photoresist layer.

[0009] According to an embodiment of the present invention, the implanted ion type includes magnesium ions; the mask thickness of the patterned mask is greater than the implantation depth of the implanted ions.

[0010] According to an embodiment of the present invention, ion implantation is performed on at least two target regions under different implantation conditions to give the gallium nitride substrate defect densities corresponding to the different implantation conditions in the at least two target regions. This includes: implanting ions with implantation doses distributed in a preset gradient in the at least two target regions; wherein the preset gradient implantation doses include low dose, medium dose, and high dose, which increase sequentially according to the dose; the target region after implantation of low-dose ions has a first defect density; the target region after implantation of medium-dose ions has a second defect density; and the target region after implantation of high-dose ions has a third defect density; wherein the third defect density is greater than the second defect density, and the second defect density is greater than the first defect density.

[0011] According to an embodiment of the present invention, the ion implantation dose range is 1×10⁻⁶. 11 ions / cm 2 ~1×10 17 ions / cm 2 The low-dose range is less than 3 × 10⁻⁶. 14 ions / cm 2 The medium dose range is 3×10. 14 ions / cm 2 ~3×10 15 ions / cm 2 The high-dose range is greater than 3 × 10⁻⁶. 15 ions / cm 2 .

[0012] According to an embodiment of the present invention, before fabricating a patterned mask on the surface of a gallium nitride substrate, the method further includes: immersing the gallium nitride substrate in acetone and performing ultrasonic cleaning, immersing the gallium nitride substrate in ethanol and performing ultrasonic cleaning, rinsing the gallium nitride substrate with deionized water and drying it.

[0013] According to an embodiment of the present invention, the critical size of the target area defined by the patterned mask on the surface of the gallium nitride substrate is 1 μm to 10 μm.

[0014] According to an embodiment of the present invention, in step S2, ion implantation is performed at room temperature; the ion implantation energy is 10 keV to 1 MeV; and the ion implantation angle deviates from the normal direction of the gallium nitride substrate by 0° to 11°.

[0015] According to an embodiment of the present invention, the method further includes, after step S2: annealing the ion-implanted gallium nitride substrate and characterizing the defects of the gallium nitride substrate using at least one of X-ray diffraction, transmission electron microscopy and Raman spectroscopy.

[0016] Compared with the prior art, the ion implantation-based selective defect control method provided by the present invention has at least the following beneficial effects:

[0017] (1) By first preparing a patterned mask on the surface of a gallium nitride substrate, the ion implantation area can be precisely defined, thereby limiting the introduction and control of defects to the pre-designed functional area and avoiding ineffective damage to the lattice of non-target areas.

[0018] (2) By performing ion implantation on at least two target regions to be implanted under different implantation conditions, the defect density can be quantitatively controlled; and by precisely controlling a specific target region (such as high-dose ion implantation), a high defect density region can be formed at the required location, thereby achieving efficient electrical or optical isolation.

[0019] (3) By combining X-ray diffraction, transmission electron microscopy and Raman spectroscopy and other multi-dimensional characterization methods, it is possible to conduct a comprehensive and quantitative analysis of the defect type, density, lattice distortion and impurity behavior after ion implantation, thereby achieving accurate evaluation and optimization of defect control. Attached Figure Description

[0020] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0021] Figure 1 The schematic diagram illustrates the steps of a selective defect control method under ion implantation according to an embodiment of the present invention;

[0022] Figure 2 The schematic diagram illustrates a process flow chart of a selective defect control method under ion implantation according to an embodiment of the present invention;

[0023] Figure 3 The X-ray diffraction patterns of gallium nitride substrates after implantation and annealing with different doses of magnesium ions according to embodiments of the present invention are illustrated schematically.

[0024] Figure 4 The illustration shows an injection dose of 6 × 10 according to an embodiment of the present invention. 15 ions / cm 2 Transmission electron microscopy images and defect distribution diagrams of gallium nitride substrates containing magnesium ions. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0026] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0027] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0028] It should also be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of the present invention. Throughout the accompanying drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding the present invention.

[0029] Figure 1 The schematic diagram illustrates the steps of a selective defect control method under ion implantation according to an embodiment of the present invention; Figure 2 The schematic diagram illustrates a process flow diagram of a selective defect control method under ion implantation according to an embodiment of the present invention.

[0030] like Figure 1 and Figure 2 As shown, in this embodiment of the invention, the selected area defect control method under ion implantation may include steps S1 to S2.

[0031] Step S1: Provide a gallium nitride substrate and prepare a patterned mask on the surface of the gallium nitride substrate to select at least two target regions on the gallium nitride substrate, wherein the gallium nitride substrate has the same defect density in the at least two target regions.

[0032] In some embodiments, the gallium nitride substrate is a gallium nitride thin film epitaxially grown on a sapphire substrate using a metal-organic chemical vapor deposition (MOCVD) method, with a thickness of, for example, 1.5 μm. In this case, each region of the gallium nitride thin film has a uniform defect density.

[0033] In some embodiments, before fabricating a patterned mask on the surface of a gallium nitride substrate, the process further includes: immersing the gallium nitride substrate in acetone and performing ultrasonic cleaning (e.g., 5 min), immersing the gallium nitride substrate in ethanol and performing ultrasonic cleaning (e.g., 5 min), rinsing the gallium nitride substrate with deionized water (e.g., 3 min), and drying.

[0034] The patterned mask is prepared by performing at least two patterning processes sequentially; in this embodiment of the invention, a custom selection area is achieved on a gallium nitride substrate by preparing a patterned mask, which can select at least two target areas.

[0035] In some embodiments, each patterning process includes: depositing a mask material layer on the surface of a gallium nitride substrate; forming a photoresist pattern on the mask material layer; and etching the mask material layer with reference to the photoresist pattern.

[0036] For example, on the cleaned gallium nitride substrate surface, a silicon oxide thin film is deposited as a mask material layer using plasma-enhanced chemical vapor deposition (PECVD). Photoresist is then coated onto this mask material layer, and a pre-defined target region pattern is transferred onto the coated photoresist using photolithography to form a photoresist pattern. Subsequently, using this photoresist pattern as a mask, dry etching is performed on the silicon oxide thin film until the underlying gallium nitride substrate surface is exposed. Finally, any remaining photoresist is removed. By performing the above patterning process at least twice in sequence, each patterning process corresponding to a different target region pattern, a patterned mask capable of defining at least two target regions can ultimately be formed on the gallium nitride substrate.

[0037] In some embodiments, each patterning process includes: forming a photoresist layer on the surface of a gallium nitride substrate; and exposing and developing the photoresist layer.

[0038] For example, photoresist is coated onto the surface of a gallium nitride substrate and cured by pre-baking to form a uniform photoresist layer. A pre-defined target area pattern is transferred onto this photoresist layer using a photolithography process. The exposed (or unexposed, depending on the type of photoresist) areas are then removed by a development process. By performing the above patterning process at least twice in sequence, each patterning process corresponding to a different target area pattern, patterned photoresist masks capable of defining individual target areas can be sequentially formed on the gallium nitride substrate. These sequentially formed and used patterned photoresist masks collectively achieve the overall definition of at least two target areas.

[0039] For example, the critical size of at least two target regions defined by the patterned mask on the surface of the gallium nitride substrate is 1 μm to 10 μm.

[0040] Step S2: Using a patterned mask, ion implantation is performed on at least two target regions under different implantation conditions, so that the gallium nitride substrate has a defect density corresponding to different implantation conditions in at least two target regions; wherein, the different implantation conditions include at least one of implanted ion type, implantation dose, implantation energy and implantation angle.

[0041] Using the patterned mask prepared in step S1 as a shield, ion implantation is performed on at least two selected target regions under different implantation conditions. These different implantation conditions include at least one difference in implanted ion type, implantation dose, implantation energy, and implantation angle.

[0042] For example, the types of ions implanted include, but are not limited to, magnesium (Mg) ions.

[0043] For example, ion implantation can be performed at room temperature.

[0044] For example, the ion implantation energy is 10keV~1MeV; the ion implantation angle deviates from the normal direction of the gallium nitride substrate by 0°~11°.

[0045] In some embodiments, ions with a preset gradient distribution of injection dose are injected into at least two target regions respectively; wherein the preset gradient distribution of injection dose includes low dose, medium dose and high dose in order of increasing dose; the target region after injection of low dose ions has a first defect density; the target region after injection of medium dose ions has a second defect density; the target region after injection of high dose ions has a third defect density; wherein the third defect density is greater than the second defect density, and the second defect density is greater than the first defect density.

[0046] For example, the ion implantation dose range is 1×10 11 ions / cm 2 ~1×10 17 ions / cm 2 The low-dose range is less than 3 × 10⁻⁶. 14 ions / cm 2 The medium dose range is 3×10. 14 ions / cm 2 ~3×10 15 ions / cm 2 The high-dose range is greater than 3 × 10⁻⁶. 15 ions / cm 2 .

[0047] For example, the mask thickness of a patterned mask is greater than the implantation depth of the implanted ions.

[0048] Through steps S1 and S2, this invention enables the control of defect density on a gallium nitride substrate via ion implantation. Furthermore, by implanting a predetermined high dose of ions into one of at least two defined target regions, the target region achieves a high defect density, effectively scattering charge carriers or photons, thereby enabling the target region to provide electrical or optical isolation.

[0049] In some embodiments, the selected defect control method under ion implantation according to the present invention further includes annealing the gallium nitride substrate after ion implantation and characterizing its defects after step S2; wherein the defect characterization methods include, but are not limited to, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy.

[0050] For example, X-ray diffraction was used to analyze the peak position shift and full width at half maximum (FWHM) variation of the characteristic crystal plane diffraction peaks of the gallium nitride substrate to quantitatively assess the lattice strain and damage degree introduced by ion implantation.

[0051] For example, high-resolution imaging and diffraction analysis using transmission electron microscopy can be used to observe the distribution and density of typical crystal defects such as prism dislocation loops and stacking faults generated by implanted ions in gallium nitride substrates.

[0052] For example, Raman spectroscopy can be used to monitor the peak position, intensity, and full width at half maximum (FWHM) variations of characteristic peaks and related defect peaks in gallium nitride (GaN) substrates to analyze the lattice stress state of GaN substrates and verify their defect modes.

[0053] Thus, this invention, through the fabrication of a patterned mask on a gallium nitride substrate that defines at least two target regions, and using this mask as a shield, performs ion implantation into each target region under different implantation conditions. This achieves the purposeful formation of defect densities on the gallium nitride substrate corresponding to different implantation conditions, thereby completing the quantifiable design and active control of gallium nitride defects. Furthermore, it can form high defect density regions at specific locations (such as high-dose implantation regions) as needed. These regions can play an electrical or optical isolation role in the device, while effectively reducing the overall lattice damage to gallium nitride caused by indiscriminately implanted ions, thereby improving the performance and reliability of gallium nitride-based devices.

[0054] Figure 3 The diagram illustrates X-ray diffraction patterns of gallium nitride substrates implanted with different doses of magnesium ions and annealed according to embodiments of the present invention.

[0055] For those without injected Mg ions and those injected with doses of 1×1014 ions / cm 2 3×10 14 ions / cm 2 5×10 14 ions / cm 2 1×10 15 ions / cm 2 3×10 15 ions / cm 2 6×10 15 ions / cm 2 Gallium nitride (GaN) substrates obtained after Mg ion removal and annealing were tested using X-ray diffraction. To accurately analyze the lattice changes along the c-axis of GaN, ω-2θ scans were performed on the GaN (0002) crystal planes. The GaN (0002) crystal planes are a set of diffraction planes perpendicular to the c-axis in wurtzite-structured GaN, and their diffraction peak positions reflect the lattice constant along the c-axis. ω-2θ scanning is a highly sensitive testing mode that couples sample tilt angle (ω) scanning with diffraction angle (2θ) scanning, effectively separating and evaluating diffraction peak changes.

[0056] like Figure 3 As shown, the horizontal axis represents the diffraction angle (2θ), with the unit being degrees; the vertical axis represents the diffraction intensity, which can be in any unit (au). Figure 3 (a) is a magnified view of a portion of the area with diffraction angles of approximately 34.2° to 34.5°.

[0057] Analysis shows that the results of no Mg ion injection and injection at doses of 1×10⁻⁶ were positive. 14 ions / cm 2 3×10 14 ions / cm 2 5×10 14 ions / cm 2 1×10 15 ions / cm 2 3×10 15 ions / cm 2 6×10 15 ions / cm 2 In the scanning results of Mg ions, the main diffraction peak of the gallium nitride (0002) plane was observed at a 2θ value of 34.54°, indicating that its c-axis orientation is consistent.

[0058] With increasing Mg ion implantation dose, the intensity of its main diffraction peak systematically decreases, reflecting the gradual degradation of the overall crystal quality of the gallium nitride substrate; when the Mg ion implantation dose reaches and exceeds 3×10 14 ions / cm2 Subsequently, a new diffraction peak appears on the lower angle side of the main diffraction peak (2θ value is approximately 34.2°~34.4°), namely the implantation-induced peak. The position of this implantation-induced peak continues to shift towards lower angles with increasing Mg ion implantation dose. At the same time, oscillating fringes (or interference fringes) appear between the implantation-induced peak and the main diffraction peak, and the number of oscillating fringes increases with increasing Mg ion implantation dose.

[0059] The above phenomena indicate that the lattice distortions induced by ion implantation in gallium nitride (such as c-axis expansion caused by interstitial atoms or substitutional defects) are not disordered, but rather periodically distributed along the depth direction (i.e., the c-axis direction). When X-rays pass through this region with periodic lattice constant variations, diffracted light from different depth regions coherently superimposes, resulting in implantation-induced peaks and interference fringes between them and the main peak. With increasing ion implantation dose, the implantation-induced peaks shift to lower angles and oscillating fringes increase, reflecting that the degree of lattice distortion and damage in gallium nitride increases with the ion implantation dose. When the Mg ion implantation dose reaches 3 × 10⁻⁶, the lattice distortion and damage increase. 15 ions / cm 2 Subsequently, the injection-induced peak and interference fringes disappeared, indicating that the periodic structure of gallium nitride lattice distortion was disrupted, and gallium nitride entered a damaged state characterized by high disorder.

[0060] The embodiments of the present invention can achieve effective and quantifiable control of the lattice strain and defect density of gallium nitride by selecting multiple target regions on a gallium nitride substrate and injecting ions with a preset gradient distribution into different target regions.

[0061] Figure 4 The illustration shows an injection dose of 6 × 10 according to an embodiment of the present invention. 15 ions / cm 2 Transmission electron microscopy images and defect distribution diagrams of gallium nitride substrates containing magnesium ions.

[0062] like Figure 4 As shown, the cross-section of the sample was observed under the condition of the [11-20] zone axis (a standard crystallographic orientation that facilitates simultaneous observation of defects on the basal and prismatic surfaces of wurtzite gallium nitride). By performing Fourier transform diffraction analysis on the transmission electron microscope images, various crystal defects introduced by this dose of ion implantation and their distribution can be identified.

[0063] Figure 4 The areas marked by the black circles (only a portion of the area is shown) exhibit obvious wavy distortion in their lattice fringes, representing highly disordered lattice distortion regions. These regions have significant non-uniformity and generate strong local lattice stress around them. Figure 4The area marked by the yellow circle contains a stacking fault basal plane located on the basal plane. This type of defect is formed by the aggregation of point defects (such as vacancies and interstitial atoms) generated by ion implantation. Figure 4 The area marked by the white circle contains a prism dislocation loop defect. This defect configuration originates from a crystallographic shearing process, where the originally intact crystal undergoes a specific shearing process. When the prism surface slips, its displacement vector (Burgess vector) lies within the prism surface.

[0064] The identified defects, such as prism dislocation loops and stacking faults, are stable morphologies resulting from the migration and aggregation of point defects generated by ion implantation. They can act as efficient absorbers for subsequent point defects, growing or shrinking by absorbing or releasing point defects, thus influencing the final evolution of the defect cluster. Although high-dose ion implantation introduces a large amount of damage, gallium nitride (GaN) itself possesses a strong ability for point defect migration and recombination due to its efficient dynamic annealing effect and unique crystal structure (the ordered hexagonal close-packed structure of wurtzite provides efficient diffusion channels for point defects both interlayer and intralayer, and the sp³ hybrid bonds of Ga-N have a certain degree of directionality and flexibility). This effectively combats damage accumulation and suppresses amorphization.

[0065] Planar defects (such as stacking faults) are known to serve as potential nucleation sites for gallium nitride amorphization. In embodiments of the invention, even at the highest experimental dose (i.e., 6 × 10⁻⁶), 15 Even at a concentration of ions / cm², gallium nitride (GaN) did not undergo complete amorphization. This phenomenon is primarily related to the highly efficient dynamic annealing effect inherent in GaN material itself. Based on these material properties, the preset gradient dose and selective implantation employed in this embodiment of the invention effectively control the defect density of GaN. Therefore, according to the design requirements of GaN devices, a more thorough isolation effect can be achieved at the desired location by further adjusting the implantation conditions (such as matching a higher implantation dose). During this process, the influence of the quality and energy of the implanted ions on the impurity distribution depth must be comprehensively considered.

[0066] In summary, this invention provides a method for selective defect control via ion implantation. By first fabricating a patterned mask on a gallium nitride substrate, the ion implantation area can be precisely defined, thereby confining the introduction and control of defects within the pre-designed functional area and avoiding ineffective damage to the lattice of non-target regions. By implanting at least two target regions with different implantation conditions, the defect density can be quantitatively controlled. Furthermore, by precisely controlling specific target regions (such as high-dose ion implantation), high defect density regions can be formed at the desired locations, achieving efficient electrical or optical isolation. By combining multi-dimensional characterization methods such as X-ray diffraction, transmission electron microscopy, and Raman spectroscopy, a comprehensive and quantitative analysis of the defect type, density, lattice distortion, and impurity behavior after ion implantation can be performed, thereby achieving precise evaluation and optimization of defect control.

[0067] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. 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 selective defect control under ion implantation, characterized in that, The method includes: Step S1: Provide a gallium nitride substrate and prepare a patterned mask on the surface of the gallium nitride substrate to select at least two target regions on the gallium nitride substrate, wherein the gallium nitride substrate has the same defect density in the at least two target regions; Step S2: Using the patterned mask, ion implantation is performed on the at least two target regions under different implantation conditions, so that the gallium nitride substrate has a defect density corresponding to the different implantation conditions in the at least two target regions; wherein, the different implantation conditions include at least one difference in implanted ion type, implantation dose, implantation energy and implantation angle.

2. The method for selective defect control under ion implantation according to claim 1, characterized in that, The patterned mask is prepared by performing at least two patterning processes sequentially.

3. The method for selective defect control under ion implantation according to claim 2, characterized in that, The graphical process includes: A masking material layer is deposited on the surface of the gallium nitride substrate; A photoresist pattern is formed on the mask material layer; Using the photoresist pattern as a reference, the mask material layer is etched.

4. The method for selective defect control under ion implantation according to claim 2, characterized in that, The graphical process includes: A photoresist layer is formed on the surface of the gallium nitride substrate; The photoresist layer is exposed and developed.

5. The method for selective defect control under ion implantation according to claim 1, characterized in that, The types of implanted ions include magnesium ions; The thickness of the patterned mask is greater than the implantation depth of the implanted ions.

6. The method for selective defect control under ion implantation according to claim 1, characterized in that, Ion implantation is performed on the at least two target regions under different implantation conditions to give the gallium nitride substrate a defect density corresponding to the different implantation conditions in the at least two target regions, including: Ions with a preset gradient distribution of injection dose are injected into the at least two target regions respectively; wherein, the preset gradient distribution of injection dose includes low dose, medium dose and high dose in order of increasing dose; The target region after implantation of the low dose of ions has a first defect density; the target region after implantation of the medium dose of ions has a second defect density; the target region after implantation of the high dose of ions has a third defect density; wherein the third defect density is greater than the second defect density, and the second defect density is greater than the first defect density.

7. The method for selective defect control under ion implantation according to claim 6, characterized in that, The implantation dose range of the ions is 1×10⁻⁶. 11 ions / cm 2 ~1×10 17 ions / cm 2 ; The low dose range is less than 3 × 10⁻⁶. 14 ions / cm 2 The dosage range of the medium dose is 3 × 10⁻⁶. 14 ions / cm 2 ~3×10 15 ions / cm 2 The high dose range is greater than 3 × 10⁻⁶. 15 ions / cm 2 .

8. The method for selective defect control under ion implantation according to claim 1, characterized in that, Before fabricating a patterned mask on the gallium nitride substrate surface, the following steps are also performed sequentially: The gallium nitride substrate was immersed in acetone and ultrasonically cleaned, then immersed in ethanol and ultrasonically cleaned, and finally rinsed with deionized water and dried.

9. The method for selective defect control under ion implantation according to claim 1, characterized in that, The critical size of the at least two target regions defined by the patterned mask on the surface of the gallium nitride substrate is 1 μm to 10 μm.

10. The method for selective defect control under ion implantation according to claim 1, characterized in that, In step S2, ion implantation is performed at room temperature; The implantation energy of the ions is 10 keV to 1 MeV; The ion implantation angle deviates from the normal direction of the gallium nitride substrate by 0° to 11°.

11. The method for selective defect control under ion implantation according to claim 1, characterized in that, The method includes the following steps after step S2: The gallium nitride substrate after ion implantation is annealed, and defects in the gallium nitride substrate are characterized by at least one of X-ray diffraction, transmission electron microscopy, and Raman spectroscopy.

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