Doping method and semiconductor device

Abstract

The invention discloses a doping method and a semiconductor device, and relates to the technical field of semiconductors, and the doping method comprises the following steps: providing a reaction container which is provided with a reaction cavity, placing a to-be-processed object in the reaction cavity, introducing a doping gas into the reaction cavity, and carrying out supercritical processing, the doping method comprises the steps that a to-be-treated object is subjected to supercritical doping, a doping fluid in a supercritical state is obtained, so that the doping fluid permeates into the to-be-treated object, standing is carried out, the to-be-treated object is repaired or doped, and doping gas comprises medium gas and doping molecules. Defect repairing or doping, surface passivation and cleaning integrated treatment of the semiconductor material is achieved, and the structural quality and the electrical performance of the material are remarkably improved.

Description

A doping method and a semiconductor device Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a doping method and a semiconductor device. Background Technology

[0002] Currently, doping techniques in the semiconductor materials field are mainly divided into two categories: primary doping methods and secondary doping methods. The primary techniques include diffusion and ion implantation. Diffusion can be further divided into thermal diffusion and gas / solid-state diffusion. Thermal diffusion uses high temperatures (800–1200°C) to drive impurity atoms to diffuse through the crystal lattice based on their concentration gradient, achieving doping. Gas / solid-state diffusion uses impurity sources such as POCl3, BBr3, or borosilicate glass to achieve doping at high temperatures. Ion implantation accelerates impurity ions to the keV–MeV energy level and directly implants them into the semiconductor surface, using precise control of the ion dosage (10¹¹–10¹¹). 6 Quantitative doping is achieved using ions / cm². Auxiliary doping methods mainly include in-situ doping and epitaxial doping: In-situ doping introduces doping gases such as PH3 and B2H6 during the material growth process (such as chemical vapor deposition or molecular beam epitaxy) to achieve simultaneous doping and film formation; Epitaxial doping involves controlling the doping concentration during epitaxial growth and is suitable for constructing multilayer heterojunctions or superlattice structures.

[0003] However, existing technologies all have significant limitations: thermal diffusion requires high-temperature processes, which can easily cause lattice damage or compositional segregation, and it is difficult to achieve shallow junction doping, with severe lateral diffusion; gas / solid diffusion has the problem of uneven impurity distribution, which especially affects the uniformity of large-area wafers, and the residual liquid or gaseous impurity sources (such as POCl3, BBr3) increase the difficulty of cleaning; although ion implantation has high precision, high-energy ion bombardment can cause lattice amorphization, which must rely on high-temperature annealing for repair, leading to impurity redistribution; in-situ doping is only suitable for thin film growth processes and cannot be used for doping bulk materials or completed device structures, and commonly used doping sources such as AsH3, PH3 and other common doping sources are highly toxic, requiring complex safety protection and exhaust gas treatment systems; epitaxial doping relies on ultra-high vacuum equipment (such as molecular beam epitaxy), which is costly, has a slow growth rate, and multilayer structures are prone to dislocations due to lattice mismatch, affecting device performance and reliability (such as a decrease in electron mobility in high electron mobility transistors). More importantly, all of the above doping methods are limited to specific manufacturing stages, lack flexibility, cannot be used as a general post-processing method, and are difficult to meet the needs of doping control for pre-formed materials or complex stacked structures.

[0004] Given the multiple limitations of existing doping technologies in terms of process temperature, material compatibility, structural adaptability, and post-processing capabilities, developing a new method that can achieve efficient, uniform, and selective doping at low temperatures while also possessing defect repair capabilities has become an urgent need for the further development of semiconductor processes. Summary of the Invention

[0005] The main objective of this invention is to provide a doping method and semiconductor device, which aims to solve the problem that existing doping technologies in the field of semiconductor materials are limited to specific manufacturing stages, lack flexibility, cannot be used as a general post-processing method, and are difficult to meet the needs of doping control for pre-formed materials or complex stacked structures.

[0006] To achieve the above objectives, the present invention proposes a doping method comprising the following steps: S10, providing a reaction container having a reaction chamber; S20, placing the object to be treated inside the reaction chamber; S30, introducing a doping gas into the reaction chamber and performing supercritical treatment to obtain a doped fluid in a supercritical state, and then permeating the doped fluid into the object to be treated to repair or dope the object, wherein the doping gas includes a dielectric gas and doping molecules.

[0007] In one embodiment, in step S30, the pressure of the doped gas introduced into the reaction chamber is 1100~10000 psi.

[0008] In one embodiment, step S30 includes heating the reaction chamber to fluidize the doped gas, thereby obtaining a doped fluid.

[0009] In one embodiment, in step S30, the temperature of the heat treatment is 31~400°C.

[0010] In one embodiment, in step S30: the dopant molecule includes at least one of acetylene, ethylene, and methane; and / or, the medium gas includes carbon dioxide.

[0011] In one embodiment, in step S30, the mass ratio of the medium gas to the dopant molecules in the doped gas is 100:(1~2).

[0012] In one embodiment, the object to be processed includes a single semiconductor material device, a device with a heterojunction structure, a single material, or a heterojunction material.

[0013] In one embodiment, after step S30, verification is further included. The verification step includes: performing transfer characteristic curve and output characteristic tests on the doped object to be treated, and then comparing them with the electrical parameters of the object to be treated before doping, and verifying whether it is qualified based on the comparison results.

[0014] The present invention also proposes a semiconductor device, which is obtained by repairing the semiconductor device according to any one of the above doping methods.

[0015] In the technical solution of this invention, the object to be processed is placed in a reaction chamber, and a doping gas composed of carbon dioxide and dopant molecules is introduced. After supercritical treatment, a doped fluid is obtained, which penetrates into the device. Defect repair is achieved under a three-dimensional high-pressure environment to obtain a doped device. In the doped fluid, the doped fluid is doped with at least doping molecules. After the medium gas reaches supercritical conditions, a supercritical fluid is formed. Utilizing its excellent dissolving ability, the doping molecules can be dissolved and enter the fluid state together. With zero surface tension and high diffusivity, the doped fluid can penetrate deeply into the micropores, deep trenches, and through-hole structures of the device material. It can effectively remove photoresist residues and metal impurities, and at the same time repair the dielectric properties (k value) of low-k materials, which is of great significance for back-end process integration. Furthermore, inside the material, the fluid-state doping molecules react chemically with the defect sites, significantly reducing dislocation defects, enhancing lattice integrity, and thus improving the single-crystal characteristics of the material. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 is a schematic diagram of the processing equipment used in Embodiment 1 of the present invention and a schematic diagram of the structure of the object to be processed; Figure 2 is a before-and-after comparison schematic diagram of the device after repairing the device after doping with doped molecules in Embodiment 1 of the present invention; Figure 3 is a model schematic diagram of the repair process of doped molecules in Embodiment 1 of the present invention; Figure 4 is a before-and-after comparison schematic diagram of the device after repairing the device by nitrogen doping in Embodiment 6 of the present invention.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0021] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0022] Due to the multiple limitations of existing doping technologies in terms of process temperature, material compatibility, structural adaptability, and post-processing capabilities, developing a new method that can achieve efficient, uniform, and selective doping at low temperatures while also possessing defect repair capabilities has become an urgent need for the further development of semiconductor processes.

[0023] In view of this, the present invention proposes a doping method, comprising the following steps: S10, providing a reaction container having a reaction chamber; S20, placing the object to be treated in the reaction chamber; S30, introducing a doping gas into the reaction chamber and performing supercritical treatment to obtain a doped fluid in a supercritical state, permeating the doped fluid into the object to be treated, and allowing it to stand to repair or dope the object to be treated, wherein the doping gas includes a dielectric gas and doping molecules.

[0024] In the technical solution of this invention, the object to be treated is placed in a reaction chamber, and a doping gas composed of a medium gas and dopant molecules is introduced. After supercritical treatment, a doped fluid is obtained. The doping molecules can be selected according to the object to be treated, allowing them to penetrate into the interior of the object to obtain a doped device. The doped fluid contains at least doping molecules. A supercritical fluid is formed through the medium gas, which utilizes its excellent dissolving ability to dissolve the doping molecules and allow them to enter the fluid state together. With zero surface tension and high diffusivity, the doped fluid can penetrate deeply into the micropores, deep trenches, and through-hole structures of the device material, effectively removing photoresist residues and metal impurities, while repairing the dielectric properties (k value) of low-k materials. This is of great significance for back-end process integration. It can also be used to dope the object to be treated, thereby improving the performance of the object, such as its electrochemical performance.

[0025] Furthermore, within the material, when the fluid-state dopant molecules and defect sites contain the same type of element, a chemical reaction can occur to repair the defects, significantly reducing dislocation defects, enhancing lattice integrity, and thus improving the single-crystal properties of the material. If the dopant molecules do not contain the same element as the defect sites, doping can be achieved, thus avoiding a single fluid state and improving the conductivity of the material.

[0026] Furthermore, doped molecules can decompose to generate active carbon species. These carbon sources can enter the semiconductor lattice as n-type or p-type dopants, adjusting carrier concentration and optimizing electrical performance. Simultaneously, they may also promote the in-situ formation of conductive nanostructures such as graphene or carbon nanotubes, further enhancing the material's conductivity. This processing condition is relatively mild and suitable for low-temperature processes, offering broader application compatibility compared to nitrous oxide passivation technology, which requires high temperatures.

[0027] It should be noted that the doped molecules can enter the device interior after reaching the critical conditions, exhibiting high solubility and permeability. This creates three-dimensional high pressure (fluid flow) near defects and dangling bonds, promoting chemical bond formation. Furthermore, the fluid can simultaneously create three-dimensional high pressure inside and outside the device, preventing damage caused by internal and external pressure.

[0028] In some embodiments, in step S30, the pressure of the doping gas introduced into the reaction chamber is 1100~10000 psi. Specifically, the pressure of the doping gas can be 1000 psi, 2000 psi, 3000 psi, 8000 psi or 10000 psi.

[0029] In some embodiments, step S30 includes heating the reaction chamber to fluidize the doped gas, thereby obtaining a doped fluid.

[0030] In some embodiments, the temperature of the heat treatment is 31~400°C. Specifically, the temperature of the heat treatment can be 31°C, 40°C, 100°C, 200°C or 400°C. Within this pressure and temperature range, the doped gas is ensured to reach and maintain a supercritical state, while the upper limit of the temperature needs to be controlled at 400°C to avoid damaging the existing device structure and meet the process requirements of "low-temperature post-processing".

[0031] In some embodiments, the dopant molecule includes at least one of acetylene, ethylene, and methane.

[0032] In fact, the dopant molecule can be any molecule, the purpose of which is to repair the defects of the device to be treated. The specific selection depends on the object to be treated. For example, it can be a carbon-containing compound with a molecular weight of less than 100 g / mol at room temperature and pressure, including but not limited to methane, ethane, ethylene, acetylene, carbon monoxide, etc. It can also be any gas, solid or liquid, such as ammonia. The gas can be uniformly dispersed in the reaction medium (such as supercritical CO2) in molecular form, and has fluidity, permeability and reactivity. It behaves as part of a "reactive fluid" to form a doped fluid to repair the defects of the device to be treated.

[0033] The medium gas is carbon dioxide because carbon dioxide forms a supercritical fluid after reaching supercritical conditions (critical temperature 31.1°C, critical pressure 7.38 MPa). Carbon dioxide is readily available, and the process for forming a supercritical fluid is simple.

[0034] In some embodiments, in step S30, the mass ratio of the medium gas to the dopant molecules in the doped gas is 100:(1~2).

[0035] Specifically, the mass ratio of the carbon dioxide fluid to the acetylene fluid can be 100:1, 100:1.5, 100:2, etc. Within the above range, efficient doping can be achieved while avoiding excessive carbon deposition, thereby inhibiting the self-polymerization or cracking of acetylene to generate amorphous carbon (carbon deposits), preventing material contamination. In addition, it can also maintain the dominant physical properties of supercritical CO2 (such as low viscosity and high diffusivity), ensure penetration ability, ensure uniform dispersion of acetylene, and avoid side reactions caused by excessively high local concentrations.

[0036] Specifically, the preparation steps of the doped fluid include: subjecting carbon dioxide and doped gas containing doped molecules to supercritical treatment so that the carbon dioxide enters a supercritical state to obtain a carbon dioxide fluid, and dissolving the doped molecules in the carbon dioxide fluid to obtain the doped fluid.

[0037] It should be noted that, taking acetylene as an example, acetylene is a highly reactive molecule. If the concentration is too high, it is prone to polymerization (generating polyacetylene) or pyrolysis (generating free carbon and hydrogen) under high temperature and pressure, causing device contamination or short circuits. Supercritical fluids have similar diffusion properties to gases and similar dissolving power to liquids, making them ideal "reaction media". Specifically, the supercritical carbon dioxide in this invention can be used as a "green solvent" to dissolve and transport acetylene and penetrate into the material, while maintaining a high proportion of carbon dioxide to ensure that its solvent properties are not damaged.

[0038] Specifically, mixing carbon dioxide and acetylene before pressurizing and heating ensures that they form a homogeneous mixture before entering the reaction chamber, avoiding local enrichment. After entering the supercritical state, carbon dioxide dissolves acetylene to form a single-phase fluid, eliminating the gas-liquid interface and improving reaction uniformity.

[0039] Specifically, as shown in Figure 3, the doped molecular model, taking acetylene as an example: Figure 3a shows the device interface state before treatment, where there are many broken bonds inside the material, forming defects; Figure 3b shows the interface state after amination; Figure 3c shows the interface state after deamination, showing the process of the broken bonds in the original material being repaired by nitrogen elements brought in by the fluid. In this process, after reaching the critical condition, the carbon dioxide fluid uses its solubility to dissolve the doped acetylene gas into the fluid, allowing acetylene to also enter the fluid state; the fluid-state carbon dioxide and acetylene permeate through the device material via the fluid's permeability. The material penetrates the pores of the device material and reacts with the active gallium dangling bonds and -NH2 groups at the defect sites. The weakly acidic acetylene molecules readily react with the weakly basic -NH2 groups to generate ammonia molecules and new gallium-carbon bonds (Ga-C). Furthermore, adjacent Ga atom defects can simultaneously react with two carbon atoms of an acetylene molecule. Finally, the generated ammonia molecules dissolve in fluid carbon dioxide and detach from the device material upon completion of the reaction, while the acetylene molecules remain inside the device and form new compounds with gallium atoms, repairing the defects on the gallium atoms. At this point, Ga-C bonds generated by the fluid carbonization repair treatment exist at the dislocation defect sites, replacing the previously abundant -NH2 groups. The formation of Ga-C bonds and the connection of adjacent defects play a role in repairing dislocation defects, enhancing lattice integrity, and thus improving the single-crystal properties of the material.

[0040] Furthermore, under higher temperature and pressure conditions, acetylene can decompose to produce active carbon species. These carbon sources can act as n-type or p-type dopants in the semiconductor lattice, adjusting carrier concentration and optimizing electrical performance. Simultaneously, they may also promote the in-situ formation of conductive nanostructures such as graphene or carbon nanotubes, further enhancing the material's conductivity. This processing condition is relatively mild and suitable for low-temperature processes, offering broader application compatibility compared to nitrous oxide passivation technology, which requires high temperatures.

[0041] In some embodiments, in step S30, the settling time is 15 to 60 minutes. Within this range, it can ensure that the doping fluid fully penetrates into the deep layers of the material or complex structures (such as porous low-k media, heterojunction interfaces), providing sufficient time for acetylene to react chemically with the –NH2 groups and Ga dangling bonds on the material surface, completing the formation of Ga–C bonds, promoting the diffusion and embedding of active carbon atoms generated by acetylene decomposition into the lattice, achieving effective doping, and avoiding incomplete reaction due to too short a time or increased side reactions due to too long a time.

[0042] It should be noted that the channels of semiconductor materials (especially porous media) are tortuous, and the molecular diffusion rate is limited. Permeation and reaction require time to drive them. Within the above range, the permeation requirements of most device structures can be covered, while taking into account both efficiency and integrity.

[0043] In some embodiments, the object to be processed includes a single semiconductor material device, a device having a heterojunction structure, a single material, or a heterojunction material.

[0044] It is understandable that semiconductor heterojunctions (such as AlGaN / GaN, Si / SiGe) have problems such as lattice mismatch, high interface state density, and many dangling bonds, which are the bottlenecks in performance. Traditional doping methods (such as ion implantation and diffusion) are difficult to precisely control the chemical state of the heterojunction interface. However, supercritical fluids can penetrate into the heterojunction interface without damage, passivate defects and introduce doping through chemical reactions, thereby improving the interface quality.

[0045] In some embodiments, after step S30, verification is further included. The verification step includes: testing the doped object to be treated, and then comparing its electrical parameters with those of the object to be treated before doping, and verifying whether it is qualified based on the comparison result.

[0046] It should be noted that the tests include transfer characteristic curves and output characteristic sequencing.

[0047] Specifically, the object to be processed is a gallium nitride high electron mobility transistor. When the doping molecule is acetylene, the specific structure is shown in Figure 1a. Figure 1b shows the repair equipment, which includes a gas cylinder, a pump, a reaction chamber, and connecting pipes. Acetylene (C2H2) and carbon dioxide (CO2) gases enter the reaction chamber through the pipes and react or deposit on the sample surface under specific conditions (such as temperature and pressure). The pump is used to regulate the pressure in the system and ensure the controllability of gas flow and reaction conditions. The entire device is compact in design, easy to operate and control, and suitable for various gas treatment and deposition processes. Furthermore, basic electrical characteristic tests are performed on the gallium nitride high electron mobility transistor to be processed, mainly including transfer characteristic curves, output characteristic curves, off-state current curves, and gate leakage current curves.

[0048] The present invention also proposes a semiconductor device, which is obtained by repairing the semiconductor device according to any one of the above doping methods.

[0049] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0050] Example 1 provides a doping method, comprising the following steps: Step 1, providing a gallium nitride high electron mobility transistor (GaN HEMT) as the object to be processed, and placing the GaN HEMT into a reaction chamber; Step 2, filling a gas cylinder with 400 mL of doping gas into a pressure pump, wherein the doping gas includes carbon dioxide and acetylene, the mass of which accounts for 1% of the doping gas; then sealing the pressure pump and pressurizing the gas to 3000 psi to form a doping gas; Step 3, introducing the doping gas from the pressure pump into the reaction chamber, then sealing the reaction chamber and heating it to 70 °C for supercritical treatment to obtain a doped fluid. The doped fluid forms a three-dimensional high pressure inside the object to be processed for repair. After the reaction chamber is left to stand for 60 min under the above conditions, the reaction chamber is cooled and depressurized to room temperature and pressure, the device is removed, and the repair process is completed, yielding a repaired device.

[0051] Example 2 differs from Example 1 in that the acetylene gas is replaced with ethylene gas; otherwise, it is similar to Example 1.

[0052] Example 3 differs from Example 1 in that the acetylene gas is replaced with methane gas, otherwise it is similar to Example 1.

[0053] Example 4 adjusts the proportion of acetylene gas in step 2 of Example 4 to "the mass of the acetylene gas accounts for 2% of the dopant gas, and the rest is similar to Example 1".

[0054] In Example 5, the proportion of acetylene gas in step 2 of Example 5 is adjusted to "the mass of the acetylene gas accounts for 0.5% of the doped gas, and the rest is similar to Example 1".

[0055] Example 6 replaces the acetylene gas in step 2 of Example 5 with ammonia gas.

[0056] In Comparative Example 1, the acetylene gas in step 2 of Comparative Example 1 is omitted, and the rest is similar to Example 1.

[0057] Examples 1-5 and Comparative Example 1 were prepared using similar steps to Example 1, with differences shown in Table 1.

[0058] Table 1. Preparation parameters of Examples 1-5 and Comparative Example 1

[0059] Performance testing was conducted on the gallium nitride high electron mobility transistor (GaN HEM) repaired in Example 1, measuring its transfer and output characteristics. Electrical parameters, including threshold voltage, on-state current, off-state leakage current, and gate leakage current, were determined. These parameters were then compared with those of Comparative Example 1, i.e., the GaN HEM before treatment. The testing instrument was a Keysight B1500A semiconductor analyzer (other semiconductor parameter analyzers may also be used). The testing methods were as follows: Transfer characteristics: The gate voltage was scanned from -15 V to 0 V, the drain voltage was 0.1 V biased, and the source voltage was 0 V; Output characteristics: The gate voltage was scanned from -12 V to -11 V in 0.2 V increments, the drain voltage was scanned from 0 V to 20 V, and the source voltage was 0 V; Off-state current: A -15 V voltage was applied to the gate, the drain voltage was scanned from 0 V to 20 V, and the source voltage was 0 V; Gate leakage current: The gate voltage was scanned from 0 V to 30 V, and both the drain and source voltages were 0 V. The electrical parameters, including threshold voltage, on-state current, off-state leakage current, and gate leakage current, are extracted from the test results; Table 2 shows the performance data obtained from Examples 1-5 and Comparative Example 1.

[0060] As shown in Table 2, the off-state leakage current was significantly reduced after repair in Examples 1 to 5, with Example 1 showing a reduction of more than 42%, while Comparative Example 1 showed almost no change. This indicates that the repair method of the present invention can effectively suppress leakage current and improve device reliability and energy efficiency.

[0061] Figure 2 shows a comparison of the electrical characteristics of the gallium nitride high electron mobility transistor before and after the doping treatment in Example 1, i.e., Example 1 and Comparative Example 1. Specifically, in Figure 2, a is the relationship between gate voltage and drain current. The black solid line represents the device characteristics before SCFT treatment, the orange dashed line represents the device characteristics after SCFT treatment, and the blue dotted line represents the device characteristics after 7 days of SCFT treatment. As can be seen from the figure, in the low gate voltage region (VGS < -10 V), all curves almost overlap, indicating that the leakage current of the device remains stable in the off state. As the gate voltage increases, the leakage current increases rapidly and enters the saturation region. The device after SCFT treatment (orange dashed line) exhibits a higher leakage current, which may be because carbon doping or defect repair improves carrier concentration and mobility. After 7 days (blue dotted line), the device performance remains basically unchanged, showing good stability.

[0062] Figure 2b shows the relationship between drain current and drain voltage. The solid black line represents the device characteristics before SCFT processing, and the dashed red line represents the device characteristics after SCFT processing. The dotted blue line represents the device characteristics 7 days after SCFT processing. As shown in the figure, in the low drain voltage region (VDS < 5 V), the three curves almost overlap, indicating that under small signal conditions, the output resistance of the device does not change much. As the drain voltage increases, the drain current gradually increases, but the three curves remain close, indicating that SCFT processing has little impact on the output characteristics of the device, mainly affecting the threshold voltage and transconductance. After 7 days, the device performance remains stable without significant degradation.

[0063] Figure 2c shows the output characteristic curves of drain voltage and drain current. The red solid line represents the device characteristics before SCFT treatment, and the blue dashed line represents the device characteristics after SCFT treatment. As can be seen from the figure, after SCFT treatment, the output characteristic curve of the device shifts to the right, indicating that the threshold voltage is reduced. Before and after SCFT treatment, the output resistance of the device does not change much, but the slope changes slightly, indicating that the carrier concentration or mobility is improved. Overall, SCFT treatment improves the output characteristics of the device, making it closer to the ideal state.

[0064] Figure 2 shows the relationship between gate current and gate voltage (d). The solid black line represents the device characteristics before SCFT processing, the dashed red line represents the device characteristics after SCFT processing, and the straight blue line represents the theoretical model fitting curve. As shown in the figure, in the low gate voltage region (VGS < 10 V), the gate current is very small, close to zero, indicating good gate insulation layer quality. With increasing gate voltage, the gate current increases rapidly, entering the nonlinear region. The device after SCFT processing (dashed red line) exhibits even lower gate current, possibly because defect repair reduces gate leakage paths. The fitting results in the figure show that after SCFT processing, the gate current distribution is more concentrated, and the slope decreases, indicating a significant improvement in the device's gate insulation performance.

[0065] In summary, Figure 2 shows that after treatment: 1. Interface defects between the gate dielectric layer and the active region are effectively repaired, lattice scattering is reduced, and the on-state current of the device increases; 2. Gate insulating layer defects are reduced, and gate leakage current in the off-state is reduced; 3. The overall performance of the device is improved. This indicates that doping treatment effectively introduces impurity elements to repair dangling bonds and material defects inside the device, further improving device performance.

[0066] The test method in Figure 4: Figure 4 shows the relationship between gate voltage and drain current. The black solid line represents the device characteristics before N-doping treatment, and the red solid line represents the device characteristics after N-doping treatment. The test method is as follows: the voltage applied to the gate is scanned from -15 V to 0 V, a 0.1 V bias voltage is applied to the drain, and the source voltage is 0 V.

[0067] The test results in Figure 4 show that, as can be seen from the figure, in the saturation region, the N-doped device (red solid line) exhibits a higher drain current, which may be because N doping increases the carrier concentration and mobility.

[0068] In summary, this invention achieves integrated treatment of defect repair, carbon doping, surface passivation and cleaning of semiconductor materials through supercritical carbon dioxide-acetylene composite fluid, significantly improving the structural quality and electrical properties of the materials.

[0069] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A doping method, characterized in that, The process includes the following steps: S10, providing a reaction vessel having a reaction chamber; S20, placing the object to be treated inside the reaction chamber; S30, introducing a doping gas into the reaction chamber and performing supercritical treatment to obtain a doped fluid in a supercritical state, permeating the doped fluid into the object to be treated, and allowing it to stand to repair or dope the object to be treated, wherein the doping gas includes a medium gas and doping molecules.

2. The doping method as described in claim 1, characterized in that, In step S30, the pressure of the doped gas introduced into the reaction chamber is 1100~10000 psi.

3. The material doping method as described in claim 1, characterized in that, In step S30, the supercritical treatment step includes: heating the reaction chamber to fluidize the doped gas to obtain a doped fluid.

4. The material doping method as described in claim 3, characterized in that, In step S30, the temperature of the heat treatment is 31~400℃.

5. The doping method as described in claim 1, characterized in that, In step S30: the dopant molecule includes at least one of acetylene, ethylene and methane; and / or, the medium gas includes carbon dioxide.

6. The doping method as described in claim 1 or 5, characterized in that, In step S30, the mass ratio of the medium gas to the doped molecules in the doped gas is 100:(1~2).

7. The doping method as described in claim 1, characterized in that, The objects to be processed include single semiconductor material devices, devices with heterojunction structures, single materials, or heterojunction materials.

8. The doping method as described in claim 1, characterized in that, After step S30, verification is also included. The verification steps include: testing the doped object to be treated, and then comparing its electrical parameters with those of the object to be treated before doping, and verifying whether it is qualified based on the comparison results.

9. A semiconductor device, characterized in that, The semiconductor device is obtained by repairing the semiconductor device according to any one of claims 1 to 8.

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