Repair method of wafer carrier

Abstract

The invention provides a method for repairing a wafer carrying disc, and the method comprises the following steps: providing a wafer carrying disc to be repaired, the wafer carrying disc to be repaired comprises a graphite substrate and a silicon carbide coating, the graphite substrate comprises a first surface and a second surface which are oppositely arranged, and the silicon carbide coating is located on the first surface; the to-be-repaired wafer loading disc is provided with a concave hole, and the concave hole penetrates through the silicon carbide coating and a part of the thickness of the graphite substrate; filling the concave hole with a repair material comprising a resin material, and graphitizing the resin material to obtain a graphitized repair structure; the maximum distance between the surface, away from the second surface, of the graphitization repair structure and the second surface is smaller than the distance between the surface, away from the graphite substrate, of the silicon carbide coating and the second surface; and forming a silicon carbide repairing structure in the concave hole, wherein the surface, away from the graphite substrate, of the silicon carbide repairing structure is flush with the surface, away from the graphite substrate, of the silicon carbide coating. Recycling and reusing of the wafer carrying disc can be achieved.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, specifically to a method for repairing a wafer carrier disk. Background Technology

[0002] As one of the core components of metal-organic chemical vapor deposition equipment, the wafer carrier is used to support the wafer substrate. It directly affects the uniformity and purity of the thin film material, and its quality directly affects the yield of the epitaxial wafer formed on it.

[0003] Wafer carriers typically consist of a graphite substrate and a silicon carbide coating covering its surface. With increased usage and changes in the process environment, the silicon carbide coating on the wafer carrier surface can become damaged or cracked, exposing the graphite substrate. Halogen gases generated during wafer fabrication react with the graphite substrate, corroding it and creating pits and voids. This leads to uneven heating and abnormal wavelengths in the epitaxial wafers formed on the wafer carrier. Damaged wafer carriers are generally scrapped and cannot be recycled, resulting in high costs. Summary of the Invention

[0004] This application addresses the shortcomings of related technologies by proposing a method for repairing wafer carriers, thereby solving the problem that scrapped wafer carriers cannot be recycled in related technologies.

[0005] This application provides a method for repairing a wafer carrier disk, including the following steps:

[0006] A wafer carrier to be repaired is provided, the wafer carrier to be repaired comprising a graphite substrate and a silicon carbide coating, the graphite substrate comprising a first surface and a second surface disposed opposite to each other, the silicon carbide coating being located on the first surface; the wafer carrier to be repaired has a recessed hole that penetrates the silicon carbide coating and a portion of the thickness of the graphite substrate.

[0007] The recessed cavity is filled with a repair material comprising resin material, and the resin material is graphitized to obtain a graphitized repair structure; the maximum distance between the surface of the graphitized repair structure away from the second surface and the second surface is less than the distance between the surface of the silicon carbide coating away from the graphite substrate and the second surface;

[0008] A silicon carbide repair structure is formed in the recess, and the surface of the silicon carbide repair structure away from the graphite substrate is flush with the surface of the silicon carbide coating away from the graphite substrate.

[0009] In some embodiments, filling the recessed cavity with a repair material comprising resin material and graphitizing the resin material to obtain a graphitized repair structure includes:

[0010] At least the recessed cavity is filled with a repair material, the repair material comprising resin material and silica powder;

[0011] The resin material is graphitized to form a graphitized repair layer.

[0012] The graphitized repair layer is etched so that the maximum distance between the surface of the graphitized repair layer away from the second surface of the graphite substrate and the second surface is less than the distance between the surface of the silicon carbide coating away from the graphite substrate and the second surface, thereby forming the graphitized repair structure.

[0013] In some embodiments, the etching process on the graphitized repair layer includes:

[0014] The graphitized repair layer is etched using an acidic etching solution, which reacts with the silicon dioxide powder.

[0015] In some embodiments, before etching the graphitized repair layer, the graphitized repair layer is partially located on the side of the silicon carbide coating away from the second surface; before etching the graphitized repair layer, the method for repairing the wafer carrier further includes:

[0016] The graphitized repair layer is thinned until the surface of the graphitized repair layer away from the graphite substrate is flush with the surface of the silicon carbide coating away from the graphite substrate.

[0017] In some embodiments, the thinning process of the graphitized repair layer includes:

[0018] The graphitized repair layer is thinned using a chemical mechanical polishing (CMP) or mechanical polishing (MRP) machine. During the thinning process, the torque of the motor of the machine is monitored, and the machine is stopped when the torque changes. Alternatively, during the thinning process, the reflectivity of the polished surface is monitored, and the machine is stopped when the reflectivity changes.

[0019] In some embodiments, the volume ratio of the resin material to the silica powder ranges from 1:3 to 1:6.

[0020] In some embodiments, the graphitization treatment of the resin material includes:

[0021] The repair material is heated to a first temperature to cure the resin material, wherein the first temperature ranges from 150 to 200°C.

[0022] The repair material is heated to a second temperature to graphitize the resin material, wherein the second temperature ranges from 900 to 1000°C.

[0023] In some embodiments, the resin material includes at least one of phenolic resin, polyimide resin, and polyacrylonitrile-based resin; and / or, the repair material further includes a graphitization aid, which includes at least one of potassium salt, sodium salt, and iron salt.

[0024] In some embodiments, forming a silicon carbide repair structure within the recess includes:

[0025] A silicon carbide film is formed on the side of the graphitized repair structure away from the second surface. The silicon carbide film partially fills the pores and partially is located on the side of the silicon carbide coating away from the second surface.

[0026] The silicon carbide film is thinned by removing the portion of the silicon carbide film that extends beyond the silicon carbide coating to form the silicon carbide repair structure.

[0027] In some embodiments, a silicon carbide thin film is formed on the side of the graphitized repair structure surface away from the second surface, including:

[0028] The wafer carrier to be repaired is placed in the reaction chamber, and a silicon carbide thin film is formed using a chemical vapor deposition process. The process conditions for the chemical vapor deposition process include:

[0029] The gas pressure range in the reaction chamber is 30–70 torr, the temperature range is 1180–1250°C, the flow rate of trichloromethylsilane is 30–50 slm, and the flow rate of hydrogen is 80–120 slm.

[0030] Alternatively, the gas pressure range of the reaction chamber is 30–70 torr, the temperature range is 1180–1250°C, the flow rate of trichlorosilane is 30–50 slm, the flow rate of ethylene is 15–30 slm, and the flow rate of nitrogen is 1–5 slm.

[0031] In some embodiments, before filling the recessed hole with a repair material comprising resin material, the method for repairing the wafer carrier further includes trimming the inner surface of the recessed hole to make the inner surface of the recessed hole a smooth surface.

[0032] The beneficial effects of this application include:

[0033] In this embodiment, for a damaged wafer carrier disk to be repaired, a graphitized repair structure is obtained by graphitizing the resin material. The graphitized repair structure is then filled into the recesses formed by the damage to the graphite substrate. Subsequently, a silicon carbide repair structure is filled into the pore areas formed by the damage to the silicon carbide coating. Since the graphitized repair structure is obtained by graphitizing the resin material in the repair material, its properties are basically the same as those of the graphite substrate. The silicon carbide repair structure is also made of the same material as the silicon carbide coating. Therefore, the structure and properties of the repaired wafer carrier disk are quite similar to those of an undamaged wafer carrier disk. The damaged wafer carrier disk can continue to be used after repair, and it can avoid uneven heating or wavelength abnormalities in the epitaxial wafer during the wafer fabrication process. In other words, this embodiment of the application can realize the recycling and reuse of damaged wafer carrier disks, saving costs.

[0034] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0035] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0036] Figure 1 , Figures 2a-2c and Figure 3 The diagram shown is a schematic representation of the steps in a wafer carrier repair method provided in an exemplary embodiment of this application.

[0037] Figures 4a-4e The diagram shown is a schematic representation of the steps of a method for repairing a wafer carrier disk provided in another exemplary embodiment of this application.

[0038] Figures 5a-5e The diagram shown is a schematic representation of the steps of a method for repairing a wafer carrier disk provided in another exemplary embodiment of this application.

[0039] Figures 6a-6c The diagram shown is a schematic representation of the steps of a method for repairing a wafer carrier disk provided in another exemplary embodiment of this application.

[0040] Figures 7a to 7k The diagram shown is a schematic representation of the steps of a wafer carrier repair method provided in another exemplary embodiment of this application. Detailed Implementation

[0041] The method for repairing the wafer carrier disk in the embodiments of this application will be described in detail below with reference to the accompanying drawings. Unless otherwise specified, the features in the following embodiments can complement or combine with each other.

[0042] like Figure 1As shown in the figure, this application provides a method for repairing a wafer carrier disk, including:

[0043] Step 100: As Figure 1 As shown, a wafer carrier to be repaired is provided. The wafer carrier to be repaired includes a graphite substrate 10 and a silicon carbide coating 20. The graphite substrate 10 includes a first surface 10a and a second surface 10b disposed opposite to each other. The silicon carbide coating 20 is located on the first surface 10a. The wafer carrier to be repaired has a recess 30 that penetrates the silicon carbide coating 20 and a portion of the thickness of the graphite substrate 10.

[0044] Step 200: As Figure 2a As shown, the recessed hole 30 is filled with a repair material 41 comprising resin material, such as... Figure 2b As shown, the resin material is graphitized, such as... Figure 2c As shown, a graphitized repair structure 40 is obtained; the maximum distance between the surface of the graphitized repair structure 40 away from the second surface 10b and the second surface 10b is less than the distance between the surface of the silicon carbide coating 20 away from the graphite substrate 10 and the second surface 10b.

[0045] Step 300: As Figure 3 As shown, a silicon carbide repair structure 50 is formed in the recess 30, and the surface of the silicon carbide repair structure 50 away from the graphite substrate 10 is flush with the surface of the silicon carbide coating 20 away from the graphite substrate 10.

[0046] In this embodiment, for the damaged wafer carrier disk to be repaired, a graphitized repair structure 40 is obtained by graphitizing the resin material. The graphitized repair structure 40 is then filled into the recesses formed by the damage to the graphite substrate 10. Subsequently, a silicon carbide repair structure 50 is filled into the recesses of the silicon carbide coating 20. Since the graphitized repair structure 40 is obtained by graphitizing the resin material in the repair material 41, its properties are basically the same as those of the graphite substrate 10. The silicon carbide repair structure 50 is also made of the same material as the silicon carbide coating 20. Therefore, the structure and properties of the repaired wafer carrier disk are similar to those of the undamaged wafer carrier disk. The damaged wafer carrier disk can continue to be used after repair, and it can avoid uneven heating or wavelength abnormalities in the epitaxial wafer during the wafer fabrication process. In other words, this embodiment of the application can realize the recycling and reuse of damaged wafer carrier disks, saving costs.

[0047] In some embodiments, the repair material 41 in step 200 includes a resin material and silica powder. The silica powder can fill the micropores and cracks in the resin material, reducing microstructural defects. This prevents the resin material from developing large cracks or gaps after filling the recesses 30, which could reduce the structural stability of the repair material 41. Simultaneously, due to the high surface activity of silica, it can effectively prevent the adhesion between the molecular chains of the resin material, facilitating full graphitization and thus improving the graphitization degree of the final graphitized repair structure 40. Furthermore, the high specific surface area of ​​silica powder can increase the contact area between the resin material and the graphite substrate 10, enhancing the adhesion between the graphitized repair structure 40 and the damaged area of ​​the graphite substrate 10, thereby improving structural stability. Simultaneously, silica powder can act as a catalyst to promote the graphitization reaction of the resin material, further enhancing its graphitization degree.

[0048] In some embodiments, the graphitization treatment of the resin material in step 200 specifically includes heating the repair material 41 to a first temperature to cure the resin material, wherein the first temperature ranges from 150 to 200°C. In some embodiments, the first temperature can be 150°C, 160°C, 170°C, 180°C, 190°C, and 200°C. Then, the repair material 41 is heated to a second temperature to graphitize the resin material, wherein the second temperature ranges from 900 to 1000°C. In some embodiments, the second temperature can be 900°C, 910°C, 920°C, 930°C, 940°C, 950°C, 960°C, 970°C, 980°C, 990°C, and 1000°C. Using a lower temperature to cure the resin material can remove volatile components from the resin material; using a higher temperature to graphitize the resin material allows carbon atoms to rearrange to form the hexagonal planar network structure characteristic of graphite. Thus, the thermal stability, electrical conductivity, and mechanical properties of the graphitized repair structure 40 formed by graphitizing the resin material are similar to those of the graphite substrate 10. The degree of restoration of the repaired wafer carrier is high. Therefore, the performance of the repaired wafer carrier after recycling and reuse can be basically consistent with the original, without affecting the wafer fabrication process.

[0049] In some embodiments, the volume ratio of resin material to silica powder ranges from 1:3 to 1:6. Within this resin range, it is beneficial to improve the thermal stability, electrical conductivity, and mechanical properties of the graphitized repair structure to be similar to those of the graphite substrate 10. In some embodiments, the volume ratio of resin material to silica powder is 1:3, 1:4, 1:5, 1:6, etc.

[0050] In some embodiments, the resin material in step 200 includes at least one of phenolic resin, polyimide resin, and polyacrylonitrile-based resin. In one example, the resin material is phenolic resin.

[0051] In some embodiments, the repair material 41 further includes a graphitization aid, which includes at least one of potassium salt, sodium salt, and iron salt. In this embodiment, the graphitization aid can reduce the temperature during the graphitization process of the resin material. The degree of graphitization of the resin increases with increasing temperature, while the graphitization aid allows the resin material to achieve a higher degree of graphitization at a lower temperature, which helps to reduce the cost of the preparation process.

[0052] In some embodiments, the weight ratio of resin material to graphitizing agent ranges from 1:4% to 1:8%. Within this range, the graphitization treatment temperature can be effectively reduced, and the graphitizing agent has a relatively small impact on the performance of the graphitized repair structure. In some embodiments, the weight ratio of resin material to graphitizing agent is 1:4%, 1:5%, 1:6%, 1:7%, or 1:8%.

[0053] In some embodiments, before filling the recess 30 with the repair material 41 comprising resin material, the method for repairing the wafer carrier disk further includes cleaning and drying the recess 30.

[0054] In some embodiments, cleaning the recess 30 may include the following steps: placing the surface of the wafer carrier disk into a cleaning furnace for cleaning, the temperature range of the cleaning furnace being 1000–1400°C, introducing a mixture of hydrogen and nitrogen gas into the cleaning furnace, wherein the concentration of hydrogen is 5%–30%, the flow rate is 40–200 SLM, and the high-temperature baking time is 4–6 hours.

[0055] In some embodiments, drying the recessed hole 30 may include the following steps: purging the surface of the wafer carrier with nitrogen gas at a pressure of 0.15–0.2 MPa and a flow rate of 0.1–0.2 L / min, for a drying time of 1–2 min.

[0056] Considering that when the recessed area 30 on the surface of the wafer carrier disk is damaged due to minor surface impact or scratches, the recessed area of ​​the recessed area 30 is small. Therefore, when filling the recessed area 30 with the repair material 41, it is impossible to precisely control the thickness of the repair material 41 filled in the wafer carrier disk. As a result, the repair material 41 fills the recessed area 30 completely, and at this time, the recessed area 30 cannot be further filled with the silicon carbide repair structure 50, or the thickness of the filled silicon carbide repair structure 50 is too small. Therefore, in some embodiments, when the repair material 41 fills the recessed area 30, step 200 specifically includes the following steps 210 to 230:

[0057] Step 210: As Figure 4a As shown, at least the recess 30 is filled with repair material 41, which includes resin material and silica powder;

[0058] Step 220: As Figure 4b As shown, the resin material undergoes graphitization treatment, such as... Figure 4c As shown, the repair material 41 forms a graphitized repair layer 42;

[0059] Step 230: As Figures 4d to 4e As shown, the graphitized repair layer 42 is etched so that the maximum distance between the surface of the graphitized repair layer 42 away from the second surface 10b of the graphite substrate 10 is less than the distance between the surface of the silicon carbide coating 20 away from the graphite substrate 10 and the second surface 10b, thus forming the graphitized repair structure 40.

[0060] In this embodiment, the graphitized repair layer 42 can be etched to form a recessed area on the wafer carrier disk on the side of the surface that is away from the graphite substrate 10 relative to the silicon carbide coating 20, so as to provide an area for subsequent filling of the silicon carbide repair structure 50.

[0061] In some embodiments, the etching process of the graphitized repair layer 42 in step 230 includes:

[0062] The graphitized repair layer 42 was etched using an acidic etching solution, which reacted with the silicon dioxide powder.

[0063] In some embodiments, the acidic etching solution can be hydrofluoric acid, and its reaction equation is as follows:

[0064] SiO2 + 4HF = SiF4↑ + 2H2O

[0065] 6HF + SiO2 = H2SiF6 + 2H2O

[0066] In this embodiment, the graphitized repair layer 42 can be wet-etched. Hydrofluoric acid does not react with silicon carbide, thus avoiding corrosion of the silicon carbide coating 20 on the wafer carrier itself. Furthermore, the etching process removes some silicon dioxide powder, which can also reduce the impact of silicon dioxide powder in the graphitized repair structure on its performance.

[0067] In some embodiments, the concentration of hydrofluoric acid ranges from 10% to 50%, and the concentration of hydrofluoric acid is 10%, 20%, 30%, 40%, or 50%.

[0068] In some embodiments, the thickness of the silicon carbide coating 20 of the wafer carrier disk along the direction from the graphite substrate 10 to the silicon carbide coating 20 is 100 nm, and the etching depth in step 230 is also 100 nm. Thus, the maximum distance between the surface of the graphitized repair structure 40 furthest from the second surface 10b and the second surface 10b is equal to the distance between the first surface 10a and the second surface 10b of the graphite substrate 10. Therefore, after the damaged graphite substrate 10 is filled with the graphitized repair structure 40, the height of each point on the first surface 10a of the graphite substrate 10 is consistent with the height of the original undamaged first surface 10a of the graphite substrate 10, which can improve the restoration similarity of the wafer carrier disk, making the structure of the repaired wafer carrier disk essentially the same as that of the undamaged wafer carrier disk.

[0069] In some embodiments, to ensure that the repair material 41 completely fills the recess, if too much repair material is used, the repair material 41 will overflow the surface of the recess 30 and cover the surface of the silicon carbide coating 20, as shown in the following example. Figure 5a As shown. Figure 5b As shown, the resin material in the repair material 41 undergoes graphitization treatment, such as... Figure 5c As shown, the graphitized repair layer 42 formed after graphitization treatment covers the side of the silicon carbide coating 20 away from the second surface 10b. Before etching the graphitized repair layer 42, the wafer carrier repair method further includes step 240:

[0070] Step 240: As Figures 5d to 5e As shown, the graphitized repair layer 42 is thinned until the surface of the graphitized repair layer 42 away from the second surface 10b of the graphite substrate 10 is flush with the surface of the silicon carbide coating 20 away from the graphite substrate 10.

[0071] In this embodiment, the portion of the graphitized repair layer 42 located on the surface of the silicon carbide coating 20 can be removed by thinning treatment, while the portion located inside the recess 30 is retained.

[0072] In one embodiment, the step of thinning the graphitized repair layer 42 includes the following process:

[0073] The graphitized repair layer 42 is thinned using chemical mechanical polishing (CMP) or mechanical polishing (MRP) equipment. During the thinning process, the torque of the motor is monitored, and the equipment is stopped when the torque changes. In this embodiment, by utilizing the resistance differences during polishing of different materials to monitor the polishing state, it is possible to precisely stop polishing after removing the graphitized repair layer 42 from the surface of the silicon carbide coating 20, thus avoiding polishing the original silicon carbide coating 20 covering the surface of the wafer carrier.

[0074] In some embodiments, the magnitude of the motor current in the chemical mechanical polishing apparatus or mechanical polishing apparatus can reflect the motor torque resistance. Therefore, by monitoring the magnitude of the motor current, the apparatus can be controlled to stop working after the graphitized repair layer 42 on the surface of the silicon carbide coating 20 is removed.

[0075] In another embodiment, the thinning process of the graphitized repair layer 42 includes: monitoring the reflectivity of the surface being polished during the thinning process, and controlling the equipment to stop operating when the reflectivity changes. The reflectance spectrum of the surface being polished reflects its reflectivity, so the equipment can be controlled by monitoring the reflectance spectrum of the surface being polished. In this embodiment, by utilizing the difference in reflectivity of different materials to monitor the polishing state, it is possible to accurately stop polishing after removing the graphitized repair layer 42 from the surface of the silicon carbide coating 20, avoiding polishing the silicon carbide coating 20 originally covering the surface of the wafer carrier.

[0076] In some embodiments, when using chemical mechanical polishing equipment, i.e., when processing by chemical mechanical planarization (CMP), cerium oxide polishing slurry can be used, and the polishing speed ranges from 100 to 300 angstroms per minute.

[0077] In some embodiments, step 300, the process of forming the silicon carbide repair structure 50 within the recess 30, includes the following steps:

[0078] Step 310: As Figure 6a As shown, a silicon carbide film 51 is formed on the side of the graphitized repair structure 40 away from the second surface 10b. The silicon carbide film 51 partially fills the recesses 30 and is located on the side of the silicon carbide coating 20 away from the second surface 10b.

[0079] Step 320: As Figures 6b-6c As shown, the silicon carbide film 51 is thinned by removing the portion of the silicon carbide film 51 that extends beyond the silicon carbide coating 20, thus forming a silicon carbide repair structure 50.

[0080] In one embodiment, step 310 includes the following process:

[0081] The wafer to be repaired is placed in the reaction chamber, and a silicon carbide thin film 51 is formed using chemical vapor deposition (CVD). The CVD process conditions include: a gas pressure range of 30–70 torr, a temperature range of 1180–1250°C, a trichloromethylsilicon (MTS) flow rate range of 30–50 SLM, and a hydrogen (H2) flow rate range of 80–120 SLM. These process conditions result in a high-quality silicon carbide repair structure.

[0082] In another embodiment, step 310 includes the following process:

[0083] The wafer to be repaired is placed in the reaction chamber, and a silicon carbide thin film 51 is formed using chemical vapor deposition (CVD). The CVD process conditions include: a gas pressure range of 30–70 torr, a temperature range of 1180–1250°C, a trichlorosilane (TCS) flow rate range of 30–50 slm, an ethylene (C₂H₄) flow rate range of 15–30 slm, and a nitrogen (N₂) flow rate range of 1–5 slm. These process conditions result in a high-quality silicon carbide repair structure.

[0084] In some embodiments, the thinning process in step 320 includes chemical mechanical polishing (CMP) or mechanical polishing. In this embodiment, thinning by CMP or mechanical polishing can make the surface of the silicon carbide repair structure 50 away from the second surface 10b flush with the surface of the silicon carbide coating 20 away from the graphite substrate 10, thereby making the surface of the repaired wafer carrier flat.

[0085] In this embodiment, a chemical mechanical polishing (CMP) device is used. That is, when the silicon carbide coating 20 is processed by chemical mechanical planarization (CMP), since the surface hardness is relatively high, diamond polishing fluid can be used, and the polishing speed ranges from 100 to 300 angstroms / minute.

[0086] In some embodiments, before step 300 and after step 200, the method for repairing the wafer carrier disk further includes the following steps: cleaning and drying the wafer carrier disk on which the graphitized repair structure 40 is formed.

[0087] In some embodiments, the cleaning process includes: spraying the surface of the wafer carrier with ultrapure water for 1-2 minutes; immersing the wafer carrier in ultrapure water for ultrasonic cleaning, with the temperature set at 20±5℃, ultrasonic generator parameters at sweep mode, frequency of approximately 40kHz, power of approximately 400-600W, and cleaning time of 5-6 minutes.

[0088] In some embodiments, the drying process includes: purging the dried surface with nitrogen gas at a pressure of 0.15–0.2 MPa and a flow rate of 0.1–0.2 L / min for a time of 1–2 min; and placing it in an oven at a temperature of 200 ± 5 °C for a baking time of 20–30 min.

[0089] In some embodiments, after step 300, the method for repairing the wafer carrier disk further includes the following step: examining the repair surface using an electron microscope to ensure that the surface is flat.

[0090] In some embodiments, before step 200, i.e., before filling the recess 30 with the repair material 41 comprising resin material, the method further includes, as... Figure 7aAs shown, the inner wall of the recess 30 is trimmed to make the inner surface of the recess 30 smooth. This ensures a smoother inner surface of the recess 30, preventing the graphitized repair structure from failing to completely fill the recess due to a rough inner surface or the presence of small grooves, thus avoiding gaps inside the recess.

[0091] In some embodiments, the recessed hole 30 is trimmed using a drill bit.

[0092] like Figures 7b-7k The diagram shows a subsequent process step after the inner wall of the recessed hole 30 is trimmed, as provided in this application. The corresponding beneficial effects are the same as in the aforementioned embodiments, and will not be repeated here.

[0093] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

Claims

1. A method for repairing a wafer carrier disk, characterized in that, include: A wafer carrier to be repaired is provided, the wafer carrier to be repaired comprising a graphite substrate and a silicon carbide coating, the graphite substrate comprising a first surface and a second surface disposed opposite to each other, the silicon carbide coating being located on the first surface; the wafer carrier to be repaired has a recessed hole that penetrates the silicon carbide coating and a portion of the thickness of the graphite substrate. The recessed cavity is filled with a repair material comprising resin material, and the resin material is graphitized to obtain a graphitized repair structure; the maximum distance between the surface of the graphitized repair structure away from the second surface and the second surface is less than the distance between the surface of the silicon carbide coating away from the graphite substrate and the second surface; A silicon carbide repair structure is formed in the recess, and the surface of the silicon carbide repair structure away from the graphite substrate is flush with the surface of the silicon carbide coating away from the graphite substrate.

2. The method for repairing a wafer carrier disk according to claim 1, characterized in that, The process of filling the concave cavity with a repair material comprising resin and then graphitizing the resin material to obtain a graphitized repair structure includes: At least the recessed cavity is filled with a repair material, the repair material comprising resin material and silica powder; The resin material is graphitized to form a graphitized repair layer. The graphitized repair layer is etched so that the maximum distance between the surface of the graphitized repair layer away from the second surface of the graphite substrate and the second surface is less than the distance between the surface of the silicon carbide coating away from the graphite substrate and the second surface, thereby forming the graphitized repair structure.

3. The method for repairing a wafer carrier disk according to claim 2, characterized in that, The etching process for the graphitized repair layer includes: The graphitized repair layer is etched using an acidic etching solution, which reacts with the silicon dioxide powder.

4. The method for repairing a wafer carrier disk according to claim 2, characterized in that, Before etching the graphitized repair layer, the graphitized repair layer is partially located on the side of the silicon carbide coating away from the second surface; before etching the graphitized repair layer, the method for repairing the wafer carrier disk further includes: The graphitized repair layer is thinned until the surface of the graphitized repair layer away from the graphite substrate is flush with the surface of the silicon carbide coating away from the graphite substrate.

5. The method for repairing a wafer carrier disk according to claim 4, characterized in that, The thinning process of the graphitized repair layer includes: The graphitized repair layer is thinned using a chemical mechanical polishing (CMP) or mechanical polishing (MRP) machine. During the thinning process, the torque of the motor of the machine is monitored, and the machine is stopped when the torque changes. Alternatively, during the thinning process, the reflectivity of the polished surface is monitored, and the machine is stopped when the reflectivity changes.

6. The method for repairing a wafer carrier disk according to claim 2, characterized in that, The volume ratio of the resin material to the silicon dioxide powder is in the range of 1:3 to 1:

6.

7. The method for repairing a wafer carrier disk according to claim 1, characterized in that, The graphitization treatment of the resin material includes: The repair material is heated to a first temperature to cure the resin material, wherein the first temperature ranges from 150 to 200°C. The repair material is heated to a second temperature to graphitize the resin material, wherein the second temperature ranges from 900 to 1000°C.

8. The method for repairing a wafer carrier disk according to claim 1, characterized in that, The resin material includes at least one of phenolic resin, polyimide resin, and polyacrylonitrile-based resin; and / or, the repair material further includes a graphitization aid, which includes at least one of potassium salt, sodium salt, and iron salt.

9. The method for repairing a wafer carrier disk according to claim 1, characterized in that, The formation of the silicon carbide repair structure within the recess includes: A silicon carbide film is formed on the side of the graphitized repair structure away from the second surface. The silicon carbide film partially fills the pores and partially is located on the side of the silicon carbide coating away from the second surface. The silicon carbide film is thinned by removing the portion of the silicon carbide film that extends beyond the silicon carbide coating to form the silicon carbide repair structure.

10. The method for repairing a wafer carrier disk according to claim 9, characterized in that, A silicon carbide thin film is formed on the side of the graphitized repair structure surface away from the second surface, comprising: The wafer carrier to be repaired is placed in the reaction chamber, and a silicon carbide thin film is formed using a chemical vapor deposition process. The process conditions for the chemical vapor deposition process include: The gas pressure range in the reaction chamber is 30–70 torr, the temperature range is 1180–1250°C, the flow rate of trichloromethylsilane is 30–50 slm, and the flow rate of hydrogen is 80–120 slm. Alternatively, the gas pressure range of the reaction chamber is 30–70 torr, the temperature range is 1180–1250°C, the flow rate of trichlorosilane is 30–50 slm, the flow rate of ethylene is 15–30 slm, and the flow rate of nitrogen is 1–5 slm.

11. The method for repairing a wafer carrier disk according to claim 1, characterized in that, Before filling the recessed hole with a repair material including resin, the method for repairing the wafer carrier further includes: trimming the inner surface of the recessed hole to make the inner surface of the recessed hole a smooth surface.

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