Silicon carbide material for integrated circuit etching equipment and preparation method thereof

Abstract

The invention relates to the technical field of materials for integrated circuit etching equipment, in particular to a silicon carbide material for integrated circuit etching equipment and a preparation method of the silicon carbide material. The preparation method comprises the following steps: selecting high-purity silicon powder and high-purity graphite micro powder, preparing slurry from the high-purity silicon powder and the high-purity graphite micro powder according to a weight ratio of 1: (1-1.5), mixing and drying; the prepared powder is synthesized at the high temperature, decarburization and secondary purification are sequentially carried out, and high-purity silicon carbide powder is obtained; the method comprises the following steps: carrying out isostatic pressing high-temperature sintering, cutting and surface sand blasting roughening treatment, and carrying out silicon carbide deposition on a roughened silicon carbide piece by utilizing a chemical vapor deposition method to obtain the silicon carbide material. The prepared silicon carbide material can meet the requirements of advanced manufacturing procedures for part materials, the machining and deposition cost can be greatly reduced, and therefore batch and large-scale production of the silicon carbide core part materials is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of materials for integrated circuit etching equipment, and in particular to a silicon carbide material for integrated circuit etching equipment and a preparation method thereof. Background Art

[0002] An integrated circuit etcher is a device that uses chemical reactions to peel off materials from the surface. It is mainly composed of a reaction chamber, a gas delivery system, a vacuum system, a control system, etc. Its working principle is to add a specific gas into the reaction chamber, decompose the gas into plasma through ionization, radiation, etc., and then introduce the plasma into the sample surface to make it react chemically, and finally achieve the purpose of etching. In the integrated circuit etcher, there is a type of component that plays an extremely critical role in the etching process, such as electrodes, grounding clamps, focusing rings, etc. This type of component has high requirements for the purity, mechanics, electricity, and etching resistance of the material. In the past, it was mainly based on silicon materials. With the continuous upgrading of the process, the limitations of silicon materials themselves can no longer meet the needs of etching equipment. Silicon carbide materials have the advantages of high temperature resistance, etching resistance, and high thermal conductivity, and have begun to gradually replace silicon materials.

[0003] At present, silicon carbide materials are mainly products prepared by pure CVD process. The silicon carbide materials prepared by this process have problems such as long time consumption, high cost, high machining difficulty and low yield.

[0004] Based on the above, although the use of silicon carbide materials to prepare core components for integrated circuit etching machines can meet the needs of more advanced processes, it still has defects such as high purity requirements, high machining difficulty, low deposition rate, and long production cycle, which seriously limit the development of silicon carbide material components.

[0005] Therefore, it is necessary to find a new method for preparing silicon carbide materials so that they can meet the requirements of advanced processes for core component materials for integrated circuit etchers, and at the same time realize mass-scale production of silicon carbide component materials. Summary of the invention

[0006] The present application provides a silicon carbide material for integrated circuit etching equipment and a preparation method thereof. The silicon carbide material prepared in the present application can not only meet the requirements of advanced processes for component materials, but also significantly reduce machining and deposition costs, thereby realizing mass production of silicon carbide core component materials.

[0007] The preparation method provided in the present application adopts a one-step carbonization and two-step purification process of high-purity raw materials to prepare high-purity silicon carbide powder, and the obtained silicon carbide powder is an ultra-high-purity powder of 3C crystal type; at the same time, a hot isostatic pressing process is adopted for sintering, and no additional sintering aid is required, thereby ensuring the purity and density of the obtained silicon carbide matrix material, and the sintered silicon carbide is used as the matrix material for chemical vapor deposition of silicon carbide to prepare silicon carbide material.

[0008] In a first aspect, the present application provides a method for preparing a silicon carbide material for an integrated circuit etching device, using the following technical solution:

[0009] A method for preparing a silicon carbide material for an integrated circuit etching device, the method comprising the following steps:

[0010] Select high-purity silicon powder and high-purity graphite powder, prepare slurry with the high-purity silicon powder and the high-purity graphite powder in a weight ratio of 1: (1-1.5), perform ball milling and mixing, and dry;

[0011] The prepared powder is synthesized at high temperature, and then decarburized at 800-1000°C for 2-10 hours to obtain silicon carbide powder;

[0012] Purifying the silicon carbide powder at 1800-1900° C. and 2000-2100° C., with the holding time being 2-10 hours and 1-4 hours, respectively, to obtain high-purity silicon carbide powder;

[0013] isostatically pressing and sintering the high-purity silicon carbide powder at high temperature to obtain a silicon carbide columnar member;

[0014] The silicon carbide columnar piece is cut and subjected to surface roughening treatment by sandblasting, and then silicon carbide is deposited on the roughened silicon carbide piece by using a chemical vapor deposition method to obtain a silicon carbide material.

[0015] Optionally, the purity of the high-purity graphite powder and the high-purity silicon powder is above 5N.

[0016] Optionally, the particle size distribution of the high-purity graphite powder and the high-purity silicon powder is 10-1000um.

[0017] Optionally, anhydrous ethanol is selected as a solvent, and high-purity silicon powder and high-purity graphite powder are prepared into a slurry in a weight ratio of 1: (1-1.5), and the amount of the anhydrous ethanol used is 1-10%.

[0018] Optionally, the ball mill used for the ball milling is made of silicon carbide.

[0019] Optionally, the ball milling time is 90-120 hours.

[0020] Optionally, the drying temperature is 60-80°C.

[0021] Optionally, the drying time is 12-24 hours.

[0022] Optionally, the sagger for containing the dried powder in the high-temperature synthesis is a graphite sagger.

[0023] Optionally, the temperature in the high temperature synthesis is 1600-1900°C.

[0024] Optionally, the holding time in the high temperature synthesis is 1-10 hours.

[0025] Optionally, during the high temperature synthesis process, the temperature is increased to 1600-1900° C. at a heating rate of 5-10° C. / min.

[0026] Optionally, the mold for containing the high-purity silicon carbide powder during the isostatic pressing and high-temperature sintering is a graphite mold.

[0027] Optionally, the sintering temperature used in the hot isostatic pressing sintering is 1600-1800°C.

[0028] Optionally, the sintering pressure used in the hot isostatic pressing sintering is 60-80 MPa.

[0029] Optionally, the sintering time used in the hot isostatic pressing sintering is 2-4 hours.

[0030] Optionally, the surface roughness range of the surface after sandblasting roughening treatment is Ra12.5-Ra6.3.

[0031] Optionally, in the surface sandblasting roughening treatment, 80-200 mesh corundum is selected to ensure that the sand grains are uniform in size and free of impurities and lumps.

[0032] Optionally, during the surface sandblasting roughening treatment, the distance between the sandblasting gun and the surface of the object to be sandblasted is adjusted to 60-150 mm.

[0033] Optionally, in the surface sandblasting roughening treatment, the sandblasting pressure is 3 kg and the sandblasting time is 20-30 min, until the sandblasted surface is uniform.

[0034] Optionally, the deposition conditions of the chemical vapor deposition method are as follows: the deposition temperature is 1300-1400° C., trichloromethylsilane is used as the raw material, hydrogen is used as the catalyst, and the protective gas is argon.

[0035] Optionally, the specific steps of the chemical vapor deposition method are as follows: placing the roughened silicon carbide part into the chamber of a chemical vapor deposition furnace, exhausting the air in the chamber, and the molecular molar ratio of MTS / H2 is 1:6; the chamber heating rate is 4.5°C / min, the deposition process temperatures are set to 1300°C and 1350°C respectively, the deposition time is 1000min, and the cooling rate is 1.7°C / min; during the process, the chamber pressure is controlled to remain at 1kPa.

[0036] In a second aspect, the present application provides a silicon carbide material for integrated circuit etching equipment prepared using the above-mentioned preparation method.

[0037] In summary, the present application includes at least one of the following beneficial technical effects:

[0038] 1. This application adopts high-purity carbon powder and high-purity silicon powder for high-temperature synthesis and purification. The process is simple and easy to industrialize. 3C crystalline silicon carbide powder is prepared with high purity and uniform particle size distribution. The silicon carbide material obtained by isostatic pressing and sintering maintains the same crystal form as the silicon carbide material prepared by chemical vapor deposition.

[0039] 2. Roughen the surface of sintered silicon carbide to ensure the cleanliness of the silicon carbide substrate surface and increase the bonding strength between the substrate material and the vapor deposited silicon carbide. After this method, the bonding strength between sintered silicon carbide and chemical vapor deposited silicon carbide is about 10MPa, while that without sandblasting is 3-5MPa.

[0040] 3. Using high-purity 3C crystal sintered silicon carbide as the matrix material to deposit silicon carbide can not only meet the material performance requirements of integrated circuit etching equipment, but also shorten the production cycle, improve product yield, and significantly reduce production costs.

[0041] 4. The present application can improve the mixing uniformity of carbon powder and silicon powder through liquid phase mixing, and the one-step carbonization and two-step purification process can improve the purity of silicon carbide powder. The hot isostatic sintering process can ensure that no impurities are introduced into the silicon carbide matrix during the sintering process, thereby ensuring the purity of the matrix material, which is between 99.99% and 99.9999%. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is the XRD test result of the sintered silicon carbide sample.

[0043] Figure 2 This is the XRD test result of the deposited silicon carbide material. DETAILED DESCRIPTION

[0044] Before describing the embodiments of the present application in detail, it should be understood that the terms used herein are only used for the purpose of describing specific embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by ordinary technicians in the field to which the terms belong.

[0045] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0046] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0047] In the present application, the terms "comprise" or "include" are open expressions, that is, including the contents specified in the present application but not excluding other contents.

[0048] The present application provides a method for preparing silicon carbide material for integrated circuit etching equipment. The preparation method specifically comprises the following steps:

[0049] (1) Material selection: high-purity graphite powder and high-purity silicon powder are selected, with a purity of 5N (99.999%) or above and a particle size distribution of 10-1000um.

[0050] (2) Mixing: Use anhydrous ethanol as the solvent, prepare a slurry of high-purity silicon powder and high-purity graphite powder in a weight ratio of 1: (1-1.5), add it into a silicon carbide ball mill, and the ball milling time is 90-120 hours.

[0051] In this step, the solvent may not be used, and the high-purity silicon powder and the high-purity graphite powder may be directly prepared into a slurry according to the weight ratio.

[0052] (3) Drying: Place the mixed slurry in a vacuum oven and dry it at 60-80°C for 12-24 hours.

[0053] (4) Synthesis: The dried powder is loaded into a graphite sagger, and the graphite sagger is placed in a vacuum degreasing sintering furnace, and the temperature is increased to 1600-1900°C at a heating rate of 5-10°C / min, and the heat preservation time is 1-10h.

[0054] (5) Decarburization: The synthesized powder is placed in a muffle furnace, oxygen is introduced, and the temperature is raised to 800-1000°C for decarburization. The heat preservation time is 2-10 hours to obtain silicon carbide powder.

[0055] (6) First purification: Place the silicon carbide powder in a vacuum degreasing sintering furnace, heat it to 1800-1900°C for purification, and keep it warm for 2-10 hours.

[0056] (7) Second purification: The powder after the first purification is crushed and placed in a vacuum degreasing furnace, heated to 2000°C for further purification, and the insulation time is 1-4 hours to obtain high-purity silicon carbide powder.

[0057] (8) Sintering: High-purity silicon carbide powder is placed in a graphite mold, and the graphite mold is placed in a hot isostatic pressing device for isostatic high-temperature sintering. The sintering temperature is 1600-1800°C, the sintering pressure is 60-80 MPa, and the sintering time is 2-4 hours to obtain silicon carbide columnar parts.

[0058] (9) Cutting and roughening treatment: The silicon carbide columnar parts are cut according to the size requirements, and the surface of the cut silicon carbide parts is roughened by sandblasting, with the roughness range being Ra12.5-Ra6.3.

[0059] The roughening process steps are as follows:

[0060] Step 1: Select 80-200 mesh corundum to ensure that the sand particles are uniform in size and free of impurities and lumps.

[0061] Step 2: Adjust the distance between the sandblasting gun and the surface of the object to be sandblasted to 60-150mm and keep it stable.

[0062] Step 3: Turn on the sandblasting equipment, the sandblasting pressure is 3kg, and the sandblasting time is 20-30min, until the sandblasted surface is uniform.

[0063] Step 4: Use a roughness tester to test the surface roughness of silicon carbide parts.

[0064] (10) The roughened silicon carbide piece is placed in a chemical vapor deposition furnace to deposit silicon carbide to obtain a silicon carbide material. The deposition conditions are as follows: the deposition temperature is 1300-1400° C., trichloromethylsilane is used as a raw material, hydrogen is used as a catalyst, and the protective gas is argon.

[0065] The specific deposition steps are as follows: Place the roughened silicon carbide parts into the chamber of the chemical vapor deposition furnace, exhaust the air in the chamber, and the molecular molar ratio of MTS / H2 is 1:6. The chamber heating rate is 4.5℃ / min, the deposition process temperature is set to 1300℃ and 1350℃ respectively, the deposition time is 1000min, and the cooling rate is 1.7℃ / min. During the process, a pump group and valve are used to control the chamber pressure to remain at 1kPa.

[0066] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. The embodiments described below are exemplary and are only used to explain the present application, and cannot be interpreted as limiting the present application.

[0067] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0068] The present application is further described in detail below in conjunction with the embodiments and test results.

[0069] Example 1

[0070] This embodiment provides a method for preparing silicon carbide material for integrated circuit etching equipment.

[0071] The above preparation method specifically comprises the following steps:

[0072] (1) Material selection: high-purity graphite powder and high-purity silicon powder are selected, with a purity of 5N (99.999%) or above and a particle size distribution of 10-1000um.

[0073] (2) Mixing: Anhydrous ethanol was used as the solvent, and high-purity silicon powder and high-purity graphite powder were prepared into a slurry in a weight ratio of 1:1. The slurry was added into a silicon carbide ball mill for 90 hours.

[0074] (3) Drying: Place the mixed slurry in a vacuum oven and dry it at 80°C for 18 hours.

[0075] (4) Synthesis: The dried powder was placed in a graphite sagger, and the graphite sagger was placed in a vacuum degreasing sintering furnace. The temperature was increased to 1800°C at a rate of 8°C / min, and the holding time was 4 h.

[0076] (5) Decarburization: The synthesized powder is placed in a muffle furnace, oxygen is introduced, and the temperature is raised to 1000°C for decarburization. The heat preservation time is 6 hours to obtain silicon carbide powder.

[0077] (6) First purification: Place the silicon carbide powder in a vacuum degreasing sintering furnace, heat it to 1800°C for purification, and keep it at this temperature for 6 hours.

[0078] (7) Second purification: The powder after the first purification is crushed and placed in a vacuum degreasing furnace, heated to 2000°C for further purification, and the heat preservation time is 2h to obtain high-purity silicon carbide powder.

[0079] (8) Sintering: High-purity silicon carbide powder is placed in a graphite mold, and the graphite mold is placed in a hot isostatic pressing device for isostatic high-temperature sintering. The sintering temperature is 1800°C, the sintering pressure is 80 MPa, and the sintering time is 2 h to obtain silicon carbide columnar parts.

[0080] (9) Cutting and roughening treatment: The silicon carbide columnar parts are cut according to the size requirements, and the surface of the cut silicon carbide parts is roughened by sandblasting, with the roughness range being Ra12.5-Ra6.3.

[0081] The roughening process steps are as follows:

[0082] Step 1: Select 100 mesh corundum to ensure that the grains are uniform in size and free of impurities and lumps.

[0083] Step 2: Adjust the distance between the sandblasting gun and the surface of the object to be sandblasted to 100mm and keep it stable.

[0084] Step 3: Turn on the sandblasting equipment, the sandblasting pressure is 3kg, and the sandblasting time is 30 minutes, until the sandblasted surface is uniform.

[0085] Step 4: Use a roughness tester to test the surface roughness of silicon carbide parts.

[0086] (10) The roughened silicon carbide piece is placed in a chemical vapor deposition furnace to deposit silicon carbide to obtain a silicon carbide material. The deposition conditions are as follows: the deposition temperature is 1300-1400° C., trichloromethylsilane is used as a raw material, hydrogen is used as a catalyst, and the protective gas is argon.

[0087] The specific deposition steps are as follows: Place the roughened silicon carbide parts into the chamber of the chemical vapor deposition furnace, exhaust the air in the chamber, and the molecular molar ratio of MTS / H2 is 1:6. The chamber heating rate is 4.5℃ / min, the deposition process temperature is set to 1300℃ and 1350℃ respectively, the deposition time is 1000min, and the cooling rate is 1.7℃ / min. During the process, a pump group and valve are used to control the chamber pressure to remain at 1kPa.

[0088] Example 2

[0089] This embodiment provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this embodiment and embodiment 1 is that in the surface sandblasting roughening step (10), the diamond grit size selected is 80 mesh, and the remaining steps are consistent with the steps of embodiment 1.

[0090] Example 3

[0091] This embodiment provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this embodiment and embodiment 1 is that in the surface sandblasting roughening step (10), the diamond grit size selected is 150 mesh, and the remaining steps are consistent with the steps of embodiment 1.

[0092] Example 4

[0093] This embodiment provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this embodiment and embodiment 1 is that in the surface sandblasting roughening step (10), the diamond grit selected is 200 mesh, and the remaining steps are consistent with the steps of embodiment 1.

[0094] Example 5

[0095] This embodiment provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this embodiment and embodiment 1 is that in the surface sandblasting roughening step of step (10), the distance between the sandblasting gun and the surface of the object to be sandblasted is adjusted to 60 mm, and the remaining steps are consistent with the steps of embodiment 1.

[0096] Example 6

[0097] This embodiment provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this embodiment and embodiment 1 is that in the surface sandblasting roughening step of step (10), the distance between the sandblasting gun and the surface of the object to be sandblasted is adjusted to 150 mm, and the remaining steps are consistent with the steps of embodiment 1.

[0098] Comparative Example

[0099] Comparative Example 1

[0100] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that it does not include the first purification step, but only includes carbonization and the second purification step, and the remaining steps are consistent with those of Example 1.

[0101] Comparative Example 2

[0102] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that it does not include a second purification step, but only includes carbonization and a first purification step, and the remaining steps are consistent with those of Example 1.

[0103] Comparative Example 3

[0104] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that it does not include the first and second purification steps, only includes the carbonization step, and the remaining steps are consistent with those of Example 1.

[0105] Comparative Example 4

[0106] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that step (10) does not include a surface sandblasting roughening treatment step, and the remaining steps are consistent with those of Example 1.

[0107] Comparative Example 5

[0108] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that in the surface sandblasting roughening step (10), the diamond grit size selected is 50 mesh, and the other steps are consistent with those of Example 1.

[0109] Comparative Example 6

[0110] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that in the surface sandblasting roughening step (10), the diamond grit size selected is 250 mesh, and the remaining steps are consistent with those of Example 1.

[0111] Comparative Example 7

[0112] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that in the surface sandblasting roughening step (10), the distance between the sandblasting gun and the surface of the object to be sandblasted is adjusted to 40 mm, and the remaining steps are consistent with those of Example 1.

[0113] Comparative Example 8

[0114] This comparative example provides a method for preparing silicon carbide material for integrated circuit etching equipment. The difference between this method and Example 1 is that in the surface sandblasting roughening step of step (10), the distance between the sandblasting gun and the surface of the object to be sandblasted is adjusted to 180 mm, and the remaining steps are consistent with those of Example 1.

[0115] Performance test results

[0116] (I) Crystal form detection

[0117] The crystal forms of the silicon carbide columnar member after isostatic pressing and the silicon carbide material after chemical vapor deposition in the above-mentioned embodiment 1 were detected.

[0118] The detection method is as follows: XRD is used to detect the crystal form of silicon carbide after sintering.

[0119] Test results such as Figure 1 and Figure 2 shown.

[0120] Depend on Figure 1 and Figure 2 It can be seen that the silicon carbide material prepared in the present application is a 3C crystal form, and the silicon carbide material obtained by isostatic pressing and sintering maintains the same crystal form as the silicon carbide material prepared by chemical vapor deposition.

[0121] (II) The purity and particle size distribution uniformity of the high-purity silicon carbide powder obtained before the sintering step in the preparation methods of the above-mentioned embodiment and comparative example were tested respectively. The testing method is as follows:

[0122] (1) Purity: The powder purity was determined by glow discharge mass spectrometry.

[0123] (2) Particle size distribution uniformity: The particle size distribution uniformity was tested using a laser particle size analyzer.

[0124] The test results are shown in Table 1.

[0125] (III) The bonding strength between the base material and the chemical vapor deposited silicon carbide in the silicon carbide materials of the above-mentioned embodiment and comparative example is tested respectively. The testing method is as follows: the bonding strength between the base material and the chemical vapor deposited silicon carbide is tested using a universal testing machine.

[0126] The test results are shown in Table 1.

[0127] Table 1 Test results

[0128]

[0129] As shown in Table 1, as the size of the sandblasting particles increases, the surface roughness of the sintered silicon carbide will increase, and the bonding force between the silicon carbide and the substrate will increase after settling. However, the particle size of the sandblasting particles will not change to a certain extent. When the sandblasting distance is short, the kinetic energy loss of the sandblasting particles is small, the impact force on the silicon carbide surface is stronger, the roughness increases, and the bonding force between the substrate and the deposited layer becomes stronger.

[0130] The powder synthesis process also has a great influence on the particle size and binding strength of the product. Lower purity and higher impurity content in the matrix will reduce the binding strength and affect the particle size of the synthesized powder.

[0131] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing silicon carbide material for integrated circuit etching equipment, characterized in that: The preparation method specifically comprises the following steps: Select high-purity silicon powder and high-purity graphite powder, prepare slurry with the high-purity silicon powder and the high-purity graphite powder in a weight ratio of 1: (1-1.5), perform ball milling and mixing, and dry; The prepared powder is synthesized at high temperature, and then decarburized at 800-1000°C for 2-10 hours to obtain silicon carbide powder; Purifying the silicon carbide powder at 1800-1900° C. and 2000-2100° C., with the holding time being 2-10 hours and 1-4 hours, respectively, to obtain high-purity silicon carbide powder; isostatically pressing and sintering the high-purity silicon carbide powder at high temperature to obtain a silicon carbide columnar member; The silicon carbide columnar piece is cut and subjected to surface roughening treatment by sandblasting, and then silicon carbide is deposited on the roughened silicon carbide piece by using a chemical vapor deposition method to obtain a silicon carbide material.

2. The preparation method according to claim 1, characterized in that: The purity of the high-purity graphite powder and the high-purity silicon powder is 5N or above; Optionally, the particle size distribution of the high-purity graphite powder and the high-purity silicon powder is 10-1000um; Optionally, anhydrous ethanol is selected as a solvent, and high-purity silicon powder and high-purity graphite powder are prepared into a slurry in a weight ratio of 1: (1-1.5), and the amount of the anhydrous ethanol used is 1-10%.

3. The preparation method according to claim 1, characterized in that: The ball mill used in the ball milling is made of silicon carbide; Optionally, the ball milling time is 90-120 hours.

4. The preparation method according to claim 1, characterized in that: The drying temperature is 60-80°C; Optionally, the drying time is 12-24 hours.

5. The preparation method according to claim 1, characterized in that: The sagger for containing the dried powder in the high temperature synthesis is a graphite sagger; Optionally, the temperature in the high temperature synthesis is 1600-1900°C; Optionally, the holding time in the high temperature synthesis is 1-10h; Optionally, during the high temperature synthesis process, the temperature is increased to 1600-1900° C. at a heating rate of 5-10° C. / min.

6. The preparation method according to claim 1, characterized in that: The mold for containing the high-purity silicon carbide powder during the isostatic pressing and high-temperature sintering is a graphite mold; Optionally, the sintering temperature used in the hot isostatic pressing sintering is 1600-1800°C; Optionally, the sintering pressure used in the hot isostatic pressing sintering is 60-80 MPa; Optionally, the sintering time used in the hot isostatic pressing sintering is 2-4 hours.

7. The preparation method according to claim 1, characterized in that: The surface roughness after the surface sandblasting roughening treatment is in the range of Ra12.5-Ra6.3; Optionally, in the surface sandblasting roughening treatment, 80-200 mesh corundum is selected to ensure that the sand grains are uniform in size and free of impurities and agglomerates; Optionally, during the surface sandblasting roughening treatment, the distance between the sandblasting gun and the surface of the object to be sandblasted is adjusted to 60-150 mm; Optionally, in the surface sandblasting roughening treatment, the sandblasting pressure is 3 kg and the sandblasting time is 20-30 min, until the sandblasted surface is uniform.

8. The preparation method according to claim 1, characterized in that: The deposition conditions of the chemical vapor deposition method are as follows: the deposition temperature is 1300-1400° C., trichloromethylsilane is used as the raw material, hydrogen is used as the catalyst, and the protective gas is argon.

9. The preparation method according to claim 1, characterized in that: The specific steps of the chemical vapor deposition method are as follows: placing the roughened silicon carbide part into the chamber of a chemical vapor deposition furnace, exhausting the air in the chamber, and the molecular molar ratio of MTS / H2 is 1:6; the chamber heating rate is 4.5°C / min, the deposition process temperatures are set to 1300°C and 1350°C respectively, the deposition time is 1000min, and the cooling rate is 1.7°C / min; during the process, the chamber pressure is controlled to remain at 1kPa.

10. A silicon carbide material for integrated circuit etching equipment prepared by the preparation method according to any one of claims 1 to 9.

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