CN114808068A - Graphite cavity inner surface treatment method, graphite cavity sheet and graphite cavity - Google Patents
Graphite cavity inner surface treatment method, graphite cavity sheet and graphite cavity Download PDFInfo
- Publication number
- CN114808068A CN114808068A CN202210191513.XA CN202210191513A CN114808068A CN 114808068 A CN114808068 A CN 114808068A CN 202210191513 A CN202210191513 A CN 202210191513A CN 114808068 A CN114808068 A CN 114808068A
- Authority
- CN
- China
- Prior art keywords
- graphite
- sheet
- cavity
- chamber
- reaction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 253
- 229910002804 graphite Inorganic materials 0.000 title claims abstract description 253
- 239000010439 graphite Substances 0.000 title claims abstract description 253
- 238000000034 method Methods 0.000 title claims abstract description 54
- 238000004381 surface treatment Methods 0.000 title claims abstract description 19
- 239000000758 substrate Substances 0.000 claims abstract description 42
- 239000002184 metal Substances 0.000 claims abstract description 30
- 229910052751 metal Inorganic materials 0.000 claims abstract description 30
- 230000008569 process Effects 0.000 claims abstract description 19
- 239000000463 material Substances 0.000 claims abstract description 17
- 239000011261 inert gas Substances 0.000 claims abstract description 14
- 239000012298 atmosphere Substances 0.000 claims abstract description 11
- 239000003792 electrolyte Substances 0.000 claims abstract description 10
- 238000002844 melting Methods 0.000 claims abstract description 8
- 230000008018 melting Effects 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 4
- 238000006243 chemical reaction Methods 0.000 claims description 30
- 239000012495 reaction gas Substances 0.000 claims description 19
- 229910001220 stainless steel Inorganic materials 0.000 claims description 16
- 239000010935 stainless steel Substances 0.000 claims description 16
- 238000002441 X-ray diffraction Methods 0.000 claims description 8
- 230000007704 transition Effects 0.000 claims description 3
- 239000013078 crystal Substances 0.000 abstract description 10
- 239000012535 impurity Substances 0.000 abstract description 9
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 239000004065 semiconductor Substances 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 62
- 238000003487 electrochemical reaction Methods 0.000 description 25
- 238000012423 maintenance Methods 0.000 description 12
- 238000012545 processing Methods 0.000 description 12
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 238000010586 diagram Methods 0.000 description 6
- 238000002425 crystallisation Methods 0.000 description 5
- 230000008025 crystallization Effects 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 238000009434 installation Methods 0.000 description 5
- 229910052786 argon Inorganic materials 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000004891 communication Methods 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 239000011241 protective layer Substances 0.000 description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 239000012300 argon atmosphere Substances 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052743 krypton Inorganic materials 0.000 description 1
- DNNSSWSSYDEUBZ-UHFFFAOYSA-N krypton atom Chemical compound [Kr] DNNSSWSSYDEUBZ-UHFFFAOYSA-N 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229910052754 neon Inorganic materials 0.000 description 1
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 229910052704 radon Inorganic materials 0.000 description 1
- SYUHGPGVQRZVTB-UHFFFAOYSA-N radon atom Chemical compound [Rn] SYUHGPGVQRZVTB-UHFFFAOYSA-N 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
- C25D7/04—Tubes; Rings; Hollow bodies
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/66—Electroplating: Baths therefor from melts
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/02—Electroplating of selected surface areas
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/54—Electroplating of non-metallic surfaces
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D9/00—Electrolytic coating other than with metals
- C25D9/04—Electrolytic coating other than with metals with inorganic materials
- C25D9/06—Electrolytic coating other than with metals with inorganic materials by anodic processes
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
The application relates to the field of semiconductor manufacturing, in particular to a graphite cavity inner surface treatment method, a graphite cavity thin plate and a graphite cavity, and the graphite cavity inner surface treatment method is used for treating the graphite thin plate on the inner surface of the graphite cavity and comprises the following steps: placing the graphite sheet as an anode and the Nb metal plate as a cathode in a container containing NaCl-NbCl 5 Mixed material electrolytic bath; under the inert gas atmosphere, NaCl-NbCl 5 Heating the mixed material to 900 ℃ to obtain NaCl-NbCl 5 Melting electrolyte and adding 5V to anode and cathodeAnd voltage is applied until the NbC layer is generated on the surface of the graphite sheet, so that the treatment process of the inner surface of the graphite cavity is simplified, the treatment cost is reduced, the generation of impurity crystals is effectively reduced, the crystals are prevented from dropping on the substrate, and the yield of the substrate is improved.
Description
Technical Field
The application relates to the field of semiconductor manufacturing, in particular to a graphite cavity inner surface treatment method, a graphite cavity thin plate and a graphite cavity.
Background
In the SiC epitaxial process, since the SiC is grown in a continuous multi-piece manner, reaction gas is introduced for a long time during the epitaxial reaction, the graphite reaction chamber has a short service life and poor economy under the reaction condition of 1700 ℃, and since the reaction gas may form Si drops on the inner surface or SiC particles on the surface during the reaction, crystals fall on the substrate, and defects are generated on the surface of the substrate, which greatly affects the yield, a thin film needs to be plated on the inner surface.
The existing coating method for the inner surface of the graphite cavity is generally to coat a TaC film on the inner surface of the graphite cavity by adopting a mechanical spraying method, so that SiC is difficult to grow on the surface of TaC or Ta, and thus reaction gas is prevented from crystallizing on the film and falling on a substrate.
In view of the above problems, no effective technical solution exists at present.
Disclosure of Invention
The application aims to provide a graphite cavity inner surface treatment method, a graphite cavity thin plate and a graphite cavity, and aims to solve the problems of high cost and complex process of plating a TaC film on the inner surface of the graphite cavity.
In a first aspect, the present application provides a graphite cavity inner surface treatment method for performing surface treatment on a graphite sheet on an inner surface of a graphite cavity in an epitaxial growth apparatus to prevent reaction gas from crystallizing on the inner surface of the graphite cavity when an epitaxial process is performed, the treatment method comprising the steps of:
s1, mixing the graphite sheetAs an anode, a Nb metal plate as a cathode is placed in the solution containing NaCl-NbCl 5 In an electrolytic cell of mixed materials;
s2, reacting the NaCl-NbCl in an inert gas atmosphere 5 Heating the mixed material to 900 ℃ to obtain NaCl-NbCl 5 And melting electrolyte, and adding a working voltage of 5V to the anode and the cathode until the NbC layer is generated on the surface of the graphite sheet.
The application provides a graphite cavity inner surface treatment method, which takes a graphite thin plate as an anode, an Nb metal plate as a cathode and NaCl-NbCl 5 The mixed material is used as electrolyte to assemble an electrochemical reaction device, and is heated to 900 ℃ in an inert gas atmosphere to obtain NaCl-NbCl 5 Melting electrolyte, adding 5V working voltage to the cathode and the anode, and enabling the surface of the graphite thin plate to generate an NbC layer, thereby preventing reaction gas from crystallizing on the thin film and falling on the substrate, replacing Ta element with Nb element, and obtaining a protective layer through simple electrochemical reaction, thereby simplifying the treatment process of the inner surface of the graphite cavity and simultaneously reducing the treatment cost.
Optionally, in the method for treating the inner surface of the graphite cavity, step S2 is performed under the following conditions:
and placing the electrolytic cell in a sealed stainless steel container for reaction.
Optionally, in the method for treating the inner surface of the graphite cavity, a layer of graphite felt is disposed in the stainless steel container, and the graphite felt is disposed between the stainless steel container and the electrolytic bath.
Optionally, the method for processing the inner surface of the graphite cavity according to the present application further includes the following steps:
s3, the uniformity, thickness and quality of the NbC layer generated by the reaction on the graphite sheet are tested by an X-ray diffraction method.
According to the method, the NbC layer is detected by using an X-ray diffraction method, and if the uniformity, the thickness and the quality of the NbC layer meet the process requirements, the graphite sheet can be arranged on the inner surface of the graphite cavity and used for protecting the inner surface of the graphite cavity.
In a second aspect, the present application further provides a graphite chamber sheet, which includes a sheet body, the sheet body is a graphite sheet, and a bottom surface of the sheet body has an NbC layer.
The application provides a graphite chamber sheet metal, regard graphite sheet metal as positive pole, Nb metal sheet as the negative pole, with NaCl-NbCl 5 The mixed material is used as electrolyte to assemble an electrochemical reaction device, and is heated to 900 ℃ in an inert gas atmosphere to obtain NaCl-NbCl 5 And melting the electrolyte, adding 5V working voltage to the cathode and the anode to generate an NbC layer on the surface of the graphite sheet, and arranging the graphite sheet on the inner top surface of the graphite cavity, so that when the substrate reacts in the graphite cavity, the reaction gas is in contact with the NbC layer on the graphite sheet and is not in direct contact with the inner surface of the graphite cavity, the phenomenon of generating impurities on the inner surface of the graphite cavity is reduced, and the yield of the substrate is improved.
Optionally, the graphite chamber thin plate of the present application, a bottom surface of the graphite chamber thin plate has a downward convex arc-shaped curved surface.
This application is provided with convex arc curved surface down through the lower surface with the graphite sheet metal, makes the reaction gas who lets in the graphite intracavity gather together in arc curved surface department, makes the more direct contact substrate of reaction gas, improves the reaction efficiency of substrate.
Optionally, the graphite chamber sheet described herein, the arc-shaped curved surface includes a first arc-shaped curved surface and a second arc-shaped curved surface that are in smooth transition, and the radius of the first arc-shaped curved surface is greater than the radius of the second arc-shaped curved surface.
This application divide into two arc curved surfaces with the arc curved surface, because the impurity that the substrate reaction generated generally including the least significant crystallization of surface and drip, consequently arrange the substrate in first arc curved surface below for the crystallization can not fall into in the substrate when dripping from the least significant of arc curved surface.
Optionally, the graphite chamber sheet of this application, first arc curved surface with the tangential direction of second arc curved surface junction is parallel with the horizontal plane.
Optionally, this application graphite chamber sheet metal, the top surface of sheet metal body has a plurality of fixture blocks, the sheet metal body passes through fixture block demountable installation is at graphite intracavity top surface.
This application sets up the sheet metal body into detachable installation at graphite intracavity top surface, and when being convenient for during the NbC on the graphite sheet metal became invalid, can change fast and need not to maintain whole graphite chamber, has reduced the cost of maintenance in graphite chamber.
In a third aspect, the present application also provides a graphite chamber for providing a reaction space for a substrate reaction, the graphite chamber comprising:
a graphite chamber body;
the graphite cavity thin plate is detachably mounted on the inner top surface of the graphite cavity main body, and the bottom surface of the graphite cavity thin plate is provided with an NbC layer.
The method takes a graphite thin plate as an anode, a Nb metal plate as a cathode and NaCl-NbCl 5 The mixed material is used as electrolyte to assemble an electrochemical reaction device, and is heated to 900 ℃ in an inert gas atmosphere to obtain NaCl-NbCl 5 The electrolyte is melted, 5V working voltage is added to the cathode and the anode, so that the surface of the graphite sheet generates an NbC layer, the graphite sheet is detachably arranged on the inner top surface of the graphite cavity, the substrate is made to react in the graphite cavity, the reaction gas is in contact with the NbC layer on the graphite sheet, impurities generated by the substrate cannot drop on the substrate, the yield of the substrate is guaranteed, meanwhile, the graphite sheet can be directly disassembled and replaced when needing to be maintained or replaced, the maintenance cost of the graphite cavity is reduced, and the maintenance efficiency is improved.
From the above, according to the graphite cavity inner surface treatment method, the graphite cavity sheet and the graphite cavity, the NbC layer is generated on the graphite sheet in the electrochemical treatment mode, the graphite sheet is detachably mounted on the top surface in the graphite cavity, when the substrate reacts in the graphite cavity, reaction gas is blocked by the NbC layer and cannot directly act on the inner surface of the graphite cavity, the graphite sheet can be maintained by directly dismounting and replacing the reaction gas, the maintenance efficiency is improved, meanwhile, the whole graphite cavity does not need to be dismounted for maintenance, and the maintenance cost is reduced.
Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. The objectives and other advantages of the application may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
Fig. 1 is a flowchart illustrating steps of a method for processing an inner surface of a graphite cavity according to an embodiment of the present disclosure.
Fig. 2 is a schematic structural diagram of a reaction apparatus for a graphite cavity inner surface treatment method according to an embodiment of the present application.
Fig. 3 is a schematic structural diagram of a graphite chamber sheet according to an embodiment of the present disclosure.
Fig. 4 is a schematic side view of a graphite chamber sheet according to an embodiment of the present disclosure.
Fig. 5 is a schematic structural diagram of a graphite chamber according to an embodiment of the present disclosure.
Description of the reference symbols: 1. a graphite cavity; 2. a substrate; 10. a graphite sheet; 11. a NbC layer; 12. a first curved surface; 13. a second curved surface; 14. a clamping block; 15. an air inlet; 16. an exhaust port; 20. a Nb metal plate; 30. an electrolytic cell; 40. NaCl-NbCl 5 Mixing the materials; 50. graphite felt; 60. a stainless steel container.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present application without making any creative effort, shall fall within the protection scope of the present application.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.
In the epitaxial process, impurities are generated on the inner surface of the graphite cavity when the substrate reacts and drop on the substrate, so that the substrate is polluted and the yield of the substrate is influenced.
In a first aspect, referring to fig. 1, fig. 1 is a flow chart illustrating steps of a graphite cavity inner surface treatment method provided in the present application, and fig. 1 illustrates a graphite cavity inner surface treatment method for performing surface treatment on a graphite thin plate 10 on an inner surface of a graphite cavity in an epitaxial growth apparatus to prevent reaction gas from crystallizing on the inner surface of the graphite cavity when an epitaxial process is performed, including the following steps:
s1, placing the graphite sheet 10 as an anode and the Nb metal plate 20 as a cathode in the solution containing NaCl-NbCl 5 In the electrolytic cell 30 of the mixed material 40;
s2, adding NaCl-NbCl in an inert gas atmosphere 5 Heating the mixed material to 900 ℃ to obtain NaCl-NbCl 5 Melting the electrolyte, and adding 5V working voltage to the anode and the cathode until the NbC layer 11 is generated on the surface of the graphite sheet 10.
Specifically, in this example, 80% NaCl and 20% NbCl were mixed in a mass ratio of the substances 5 Mixed into NaCl-NbCl 5 Mixing material 40, NaCl-NbCl 5 The mixed material 40 is heated at 600 ℃ for 24 hours to dehydrate it for use.
Specifically, referring to fig. 2, fig. 2 is a schematic structural diagram of a reaction apparatus for a graphite cavity inner surface treatment method provided in the present application, since corrosive chemical substances are generated in an electrochemical reaction process, in order to increase a service life of an electrolytic cell 30, a high-purity graphite crucible with high corrosion resistance is selected as the electrolytic cell 30 for the electrochemical reaction.
Alternatively, the inert gas may be helium, neon, argon, krypton, xenon, radon, or the like, and in this embodiment, argon, which is most commonly used, is selected as the inert gas, so that the electrochemical reaction is performed in an argon atmosphere.
Optionally, a temperature measurement and control device is disposed in the electrolytic cell 30 for monitoring the real-time temperature in the electrolytic cell 30 and controlling the temperature in the electrolytic cell 30 to be about 900 ℃, and since the temperature in the electrolytic cell 30 is relatively high, a thermocouple may be selected to measure the temperature in the electrolytic cell 30, and preferably, a K-type thermocouple is selected to measure the temperature in the electrolytic cell 30 in this embodiment.
In some embodiments, a TaC layer is formed on the surface of the graphite sheet 10 by electrochemical reaction of Ta metal, but Ta may be formed due to reaction of Ta with C 2 C by-product and Ta metal is relatively high in cost, so that preferably, Nb metal is selected to replace Ta metal for electrochemical reaction, so as to generate an NbC layer 11 on the surface of the graphite sheet 10, and Nb is selected to replace Ta for reaction, so as to be difficult to generate by-product, so that the purity of the NbC layer can be improved, the melting point of the NbC layer 11 is 3500 ℃, which is lower than the melting point of 3880 ℃ of TaC, so that NbC is easier to prepare than TaC, and the preparation cost of the graphite sheet 10 is reduced by selecting Nb to replace Ta for preparing the protective layer.
In the method for processing the inner surface of the graphite cavity in the embodiment of the application, the graphite thin plate 10 is used as an anode, the Nb metal plate 20 is used as a cathode, and NaCl-NbCl is used 5 The mixed material 40 is put into the electrolytic cell 30 to assemble an electrochemical reaction device, 5V working voltage is added to the cathode and the anode, the graphite sheet 10 is heated to 900 ℃ in the inert gas atmosphere, so that the NbC layer 11 is generated on the surface of the graphite sheet 10, and because the metal Ta and the metal Nb are the same group metals and have similar properties, in the embodiment, the lower-cost Nb element is used for replacing the higher-cost Ta element, and the NbC layer 11 can be obtained through simple electrochemical reaction, the treatment process of the inner surface of the graphite cavity is simplified, the processing cost of the inner surface protection layer of the graphite cavity is reduced, meanwhile, the inner surface of the graphite cavity can be prevented from crystallizing and falling on the substrate, and the yield of the substrate is ensured.
In some preferred embodiments, step S2 is performed under the following conditions:
the electrolytic cell 30 was placed in a sealed stainless steel container 60 for reaction.
Alternatively, referring to fig. 2, in the present embodiment, since the electrolytic cell 30 is made of a graphite crucible with strong thermal conductivity and the electrochemical reaction needs to be performed at 900 ℃, the electrolytic cell 30 needs to be placed in a high temperature resistant container to perform the electrochemical reaction, alternatively, in some embodiments, a glass container, a ceramic container, a stainless steel container, or the like can be used as the container of the electrolytic cell 30, and preferably, in the present embodiment, a stainless steel container 60 with low cost is used as the container of the electrolytic cell 30.
Specifically, the stainless steel container 60 needs to be sealed, and an inert gas argon is introduced into the sealed stainless steel container 60 to enable the electrochemical reaction to be performed in an inert gas atmosphere, wherein the argon is used as a protective gas in the electrochemical reaction to prevent the oxidation reaction from generating byproducts in the electrochemical reaction process.
In some preferred embodiments, a layer of graphite felt 50 is disposed in the stainless steel container 60, with the graphite felt 50 disposed between the stainless steel container 60 and the electrolytic cell 30.
Specifically, referring to fig. 2, a graphite felt 50 is disposed on the inner surface of the stainless steel container 60 for keeping warm to keep the temperature inside the stainless steel container 60 stable.
In some preferred embodiments, the graphite cavity inner surface treatment method further comprises the following steps:
s3, the uniformity, thickness and quality of the NbC layer 11 formed by the reaction on the graphite sheet 10 were examined by X-ray diffraction.
Specifically, during the electrochemical reaction, since the current is unstable or impurities are introduced into the electrolytic cell 30, the thickness, uniformity and quality of the NbC layer 11 are affected, and the effect of the NbC layer 11 on preventing the crystal from dropping is affected, so that the NbC layer 11 on the graphite sheet 10 needs to be inspected, specifically, in this embodiment, the NbC layer 11 is inspected by using an X-ray diffraction method, when the thickness, uniformity and quality of the NbC layer 11 meet the process requirements, the graphite sheet 10 is qualified, and if at least one of the thickness, uniformity and quality of the NbC layer 11 does not meet the process requirements, the graphite sheet 10 is not qualified.
Specifically, the principle of the X-ray diffraction method is that when a monochromatic X-ray is incident on a crystal, the crystal is composed of unit cells formed by regularly arranged atoms, the distance between the regularly arranged atoms has the same order of magnitude as the wavelength of the incident X-ray, so that the X-rays scattered by different atoms interfere with each other to generate strong X-ray diffraction in certain special directions, the orientation and intensity of the diffraction lines in spatial distribution are closely related to the crystal structure, and the uniformity and thickness of the NbC layer 11 and the quality or purity of the NbC layer 11 can be analyzed according to the diffraction pattern obtained by the X-ray diffraction method.
In a second aspect, referring to fig. 3, fig. 3 is a schematic structural diagram of a graphite chamber thin plate provided in the present application, and the graphite chamber thin plate shown in fig. 3 includes a thin plate body, which is a graphite thin plate 10, and a bottom surface of the thin plate body has an NbC layer 11.
In this embodiment, a graphite sheet 10 is mounted on the inner top surface of the graphite chamber 1.
Specifically, in the present embodiment, the graphite chamber 1 for performing the epitaxial process may be manufactured by the following steps:
a1, in the existing graphite cavity 1, processing an installation groove for installing the graphite thin plate 10 on the inner top surface of the graphite cavity 1;
a2, processing the Nb metal plate into a graphite thin plate 10 with the size matched with the inner top surface of the graphite cavity 1 according to the size of the inner top surface of the graphite cavity 1, and processing a fixture block 14 matched with the installation groove on the inner top surface of the graphite thin plate 10;
a3, forming NbC layers 11 on the surfaces of the graphite sheets 10 by electrochemical reaction (this step A3 can be specifically realized by the above-mentioned method for treating the top surfaces in the graphite cavities);
a4, a graphite sheet 10 with NbC layers 11 was mounted on the top inner surface of the graphite chamber 1.
The graphite chamber 1 is manufactured through the steps, the detachable graphite sheet 10 is installed on the inner top surface of the graphite chamber 1, and the NbC layer 11 is plated on the surface of the graphite sheet 10 and used for preventing the reaction gas from crystallizing on the inner top surface of the graphite chamber 1 and falling on the substrate 2 when the epitaxial process is carried out.
Specifically, in the present embodiment, the reaction performed in the embodiment is SiC epitaxial reaction, since the reaction gas needs to be continuously introduced during the reaction process of the substrate 2, and the reaction process needs to be performed at 1700 ℃, when the high-temperature reaction gas is introduced into the graphite chamber 1 for a long time, Si droplets or SiC particles are generated on the inner top surface of the graphite chamber 1, and in order to reduce impurities generated on the inner top surface of the graphite chamber, the graphite sheet 10 having the NbC layer 11 needs to be installed on the inner top surface of the graphite chamber 1, specifically, the NbC layer 11 faces the substrate 2 in the graphite chamber 1.
In the examples of the present application, a graphite sheet 10 was used as an anode, a Nb plate 20 was used as a cathode, and NaCl-NbCl was used 5 The mixed material 40 is put into an electrolytic bath 30 to form an electrochemical reaction device, 5V working voltage is added to a cathode and an anode, the graphite sheet 10 is heated to 900 ℃ in an inert gas atmosphere, so that an NbC layer 11 is generated on the surface of the graphite sheet 10, the graphite sheet 10 is arranged on the inner top surface of a graphite cavity 1, so that when a substrate 2 reacts in the graphite cavity 1, the reaction gas is contacted with the NbC layer 11 on the graphite sheet 10 and is not directly contacted with the inner top surface of the graphite cavity 1, thereby reducing the generation of impurities on the inner surface of the graphite cavity 1 and dropping on the substrate, the application uses Nb element with lower cost to replace Ta element with higher cost, and can obtain the NbC layer 11 through simple electrochemical reaction, simplify the processing technology of the inner surface of the graphite cavity, simultaneously reduce the processing cost of a protective layer on the inner surface of the graphite cavity, and simultaneously can prevent the inner top surface of the graphite cavity from crystallizing and dropping on the substrate, the yield of the substrate is ensured.
In some preferred embodiments, the bottom surface of the graphite chamber sheet has a downwardly convex curved surface.
Specifically, according to the crystallization principle, the larger the radian of the convex arc-shaped curved surface on the surface is, the more the number of atoms required for crystallization on the surface is, and therefore, the bottom surface of the graphite cavity thin plate is set to be the arc-shaped curved surface which protrudes downward, and SiC can be prevented from crystallizing and dripping onto the substrate 2 on the inner top surface of the graphite cavity 1.
In some preferred embodiments, the curved surfaces include a first curved surface 12 and a second curved surface 13 with smooth transitions, and the radius of the first curved surface 12 is larger than the radius of the second curved surface 13.
Specifically, the first curved arc surface 12 and the second curved arc surface 13 should be arranged along the air feeding direction of the graphite chamber 1 when being installed, the starting point of the first curved arc surface 12 is arranged above the air inlet 15 of the graphite chamber 1 and is about 0-10mm away from the air inlet 15, in this embodiment, the starting point of the first curved arc surface 12 is arranged about 10mm above the air inlet 15, and the end point of the second curved arc surface 13 is arranged at a side close to the air outlet 16, preferably, in this embodiment, the first curved arc surface 12 is arranged above a substrate tray for supporting the substrate 2, so that when the thin plate on the top surface in the graphite chamber 1 is crystallized, SiC is concentrated at the end point of the first curved arc surface 12, that is, the lowest point of the first curved arc surface 12, and when the SiC crystal falls, the SiC crystal cannot fall on the substrate 2, thereby ensuring the growth yield of the substrate 2.
Specifically, the starting point of the second arc-shaped curved surface 13 is smoothly connected with the end point of the first arc-shaped curved surface 12, the end point of the second arc-shaped curved surface 13 is located at the exhaust port 16, and in addition, the distance between the connecting part of the first arc-shaped curved surface 12 and the second arc-shaped curved surface 13 and the inner top surface of the graphite cavity cannot be greater than the distance between the inner top surface and the inner bottom surface of the graphite cavity, so that the reaction gas cannot circulate in the graphite cavity 1.
Alternatively, in some embodiments, the graphite sheet 10 is in a regular cube shape, the NbC layer 11 is generated at the bottom of the graphite sheet 10 through an electrochemical reaction, so that the NbC layer 11 has a downwardly convex curved surface, and the electrochemical reaction is difficult to accurately generate the NbC layer 11 with the curved surface having the above shape requirement, and the generated NbC layer 11 has a non-uniform thickness, so that it is difficult to ensure that the thickness of the NbC layer 11 meets the process requirement, therefore, preferably, the bottom of the graphite sheet 10 is processed into a downwardly convex curved surface, the processing of the curved surface is convenient, and the thickness of the NbC layer 11 generated on the curved surface is convenient to measure, which not only saves the processing cost, but also improves the yield of the NbC layer 11.
In some preferred embodiments, the tangential direction of the junction of the first curved surface 12 and the second curved surface 13 is parallel to the horizontal plane.
Specifically, in order to make the gas flow more smoothly and stably in the graphite chamber 1, it is preferable that the tangential direction of the junction of the first curved surface 12 and the second curved surface 13 is parallel to the horizontal plane.
In some preferred embodiments, the top surface of the thin plate body has a plurality of latches 14, and the thin plate body is detachably mounted on the top surface in the graphite chamber 1 through the latches 14.
Specifically, in this embodiment, refer to fig. 4, fig. 4 is a structural side view of the graphite sheet provided by this application, the two sides of the fixture block 14 on the top surface of the sheet body have hooks, the inner top surface of the graphite cavity 1 is provided with a mounting groove for mounting the fixture block 14, when the graphite sheet 10 is mounted on the inner top surface of the graphite cavity 1 through the cooperation of the fixture block 14 and the mounting groove, the hooks are embedded into the mounting groove, thereby fixing the graphite sheet 10, the maintenance cost of the graphite cavity 1 is reduced by detachably mounting the graphite sheet 10 on the inner top surface of the graphite cavity 1, when the NbC layer 11 on the graphite sheet 10 is damaged or loses the protection function, the repair and maintenance can be completed only by replacing the graphite sheet 10, and the maintenance of the whole graphite cavity 1 is not needed.
Preferably, in this embodiment, when the reaction gas enters the graphite chamber 1 from the gas inlet 15 and acts on the first curved surface 12, a pushing force is generated on the graphite sheet 10, and the graphite sheet 10 slides along the mounting groove on the inner top surface of the graphite chamber 1 under the pushing force, so that, in order to prevent the graphite sheet 10 from sliding, a top block can be disposed at the gas outlet 16 for preventing the graphite sheet 10 from sliding along the gas flow direction.
Specifically, in the present embodiment, only the NbC layer 11 is formed on the bottom surface of the graphite sheet 10 by reaction, and the NbC layer 11 is formed on each surface of the graphite sheet 10 during the chemical reaction, so that, in order to form the NbC layer on the bottom surface of the graphite sheet 10 in a concentrated manner, an insulating layer or a non-reactive layer is optionally wrapped on the other surfaces except the bottom surface of the graphite sheet 10, and after the electrochemical reaction is completed, the insulating layer or the non-reactive layer is torn off, so that the graphite sheet 10 having the NbC layer 11 only on the bottom of the graphite sheet 10 can be obtained.
In a third aspect, referring to fig. 5, fig. 5 is a schematic structural diagram of a graphite chamber provided in the present application, where fig. 5 shows a graphite chamber 1 for providing a reaction space for a substrate 2 reaction, the graphite chamber 1 includes:
a graphite chamber body;
the graphite cavity sheet metal, graphite cavity sheet metal demountable installation is at the interior top surface of graphite cavity main part, and the bottom surface of graphite cavity sheet metal has NbC layer 11.
In the embodiment of the application, the graphite cavity thin plate is used as the anode, the Nb metal plate 20 is used as the cathode, and NaCl-NbCl is used 5 The mixed material 40 is put into an electrolytic bath 30 to form an electrochemical reaction device, 5V working voltage is added to a cathode and an anode, the cathode and the anode are heated to 900 ℃ in an inert gas atmosphere, an NbC layer 11 is generated on the surface of the graphite cavity thin plate, and the graphite cavity thin plate is detachably arranged on the inner top surface of the graphite cavity main body. The lower Nb element of this scheme use cost replaces the higher Ta element of cost to can obtain NbC layer 11 through simple electrochemical reaction, the treatment process of graphite intracavity surface has been simplified, the processing cost of graphite intracavity surface protection layer has been reduced simultaneously, can prevent graphite intracavity top surface crystallization and drop on the substrate simultaneously, the yield of substrate has been guaranteed, can directly dismantle the change when graphite chamber sheet metal needs maintenance or change simultaneously, reduce the cost of maintenance of graphite chamber 1, the efficiency of maintenance is improved.
In the specific implementation process, the graphite sheet 10 is not limited to be installed on the inner top surface of the reaction chamber 1, and the graphite sheet 10 may also be installed on other inner side walls of the reaction chamber 1 for reducing impurity crystal generation.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. The above-described embodiments of the apparatus are merely illustrative, and for example, a division of a unit is merely a division of one logic function, and there may be other divisions when actually implemented, and for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed coupling or direct coupling or communication connection between each other may be through some communication interfaces, indirect coupling or communication connection between devices or units, and may be in an electrical, mechanical or other form.
In addition, units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
Furthermore, the functional modules in the embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
In this document, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.
The above embodiments are merely examples of the present application and are not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. A graphite cavity inner surface treatment method for performing surface treatment on a graphite sheet (10) of a graphite cavity inner surface in an epitaxial growth apparatus to prevent reaction gas from crystallizing on the graphite cavity inner surface when an epitaxial process is performed, the treatment method comprising the steps of:
s1, placing the graphite sheet (10) as an anode and the Nb metal plate (20) as a cathode in a container with NaCl-NbCl 5 In an electrolytic cell (30) of mixed material (40);
S2、under an inert gas atmosphere, the NaCl-NbCl is added 5 Heating the mixed material (40) to 900 ℃ to obtain NaCl-NbCl 5 Melting electrolyte, and adding 5V working voltage to the anode and the cathode until the NbC layer (11) is generated on the surface of the graphite sheet (10).
2. The method for treating the inner surface of the graphite cavity according to claim 1, wherein the step S2 is performed under the following conditions:
the electrolytic cell (30) is placed in a sealed stainless steel container (60) for reaction.
3. The graphite cavity inner surface treatment method according to claim 2, wherein a graphite felt (50) is provided in the stainless steel container (60), and the graphite felt (50) is provided between the stainless steel container (60) and the electrolytic bath (30).
4. The method for treating the inner surface of the graphite cavity according to claim 1, further comprising the steps of:
s3, the uniformity, thickness and quality of the NbC layer (11) formed by the reaction on the graphite sheet (10) are tested by an X-ray diffraction method.
5. A graphite chamber sheet comprising a sheet body which is a graphite sheet (10), characterized in that the bottom surface of the sheet body has a layer of NbC (11).
6. The graphite chamber sheet of claim 5, wherein the bottom surface of the graphite chamber sheet has a downwardly convex curved surface.
7. The graphite chamber sheet of claim 6, wherein the curved surfaces comprise a first curved surface (12) and a second curved surface (13) having smooth transitions, and wherein the radius of the first curved surface (12) is greater than the radius of the second curved surface (13).
8. The graphite chamber sheet of claim 7, wherein the tangential direction of the junction of the first curved surface (12) and the second curved surface (13) is parallel to the horizontal plane.
9. The graphite chamber sheet according to claim 5, wherein the top surface of the graphite chamber sheet is provided with a plurality of clamping blocks (14), and the graphite chamber sheet is detachably arranged on the inner top surface of the graphite chamber (1) through the clamping blocks (14).
10. A graphite chamber for providing a reaction space for a substrate (2) reaction, the graphite chamber (1) comprising:
a graphite chamber body;
the graphite cavity thin plate is characterized in that the graphite cavity thin plate is detachably arranged on the inner top surface of the graphite cavity main body, and the bottom surface of the graphite cavity thin plate is provided with an NbC layer (11).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210191513.XA CN114808068B (en) | 2022-03-01 | 2022-03-01 | Graphite cavity inner surface treatment method, graphite cavity thin plate and graphite cavity |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210191513.XA CN114808068B (en) | 2022-03-01 | 2022-03-01 | Graphite cavity inner surface treatment method, graphite cavity thin plate and graphite cavity |
Publications (2)
Publication Number | Publication Date |
---|---|
CN114808068A true CN114808068A (en) | 2022-07-29 |
CN114808068B CN114808068B (en) | 2024-04-05 |
Family
ID=82529292
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210191513.XA Active CN114808068B (en) | 2022-03-01 | 2022-03-01 | Graphite cavity inner surface treatment method, graphite cavity thin plate and graphite cavity |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN114808068B (en) |
Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1396455A (en) * | 1972-05-04 | 1975-06-04 | Toyoda Chuo Kenkyusho Kk | Method of forming a carbide layer |
CA2330982A1 (en) * | 2001-01-15 | 2002-07-15 | Linamar Corporation | Deposition and thermal diffusion of borides and carbides of refractory metals |
CN103014793A (en) * | 2012-12-11 | 2013-04-03 | 广东电网公司电力科学研究院 | Method for preparing titanium carbide coating through pulse electrodeposition |
CN103370764A (en) * | 2010-12-16 | 2013-10-23 | 皇家飞利浦电子股份有限公司 | Anode disk element with refractory interlayer and VPS focal track |
CN104246023A (en) * | 2012-04-20 | 2014-12-24 | 贰陆股份公司 | LARGE DIAMETER, HIGH QUALITY SiC SINGLE CRYSTALS, METHOD AND APPARATUS |
CN208308999U (en) * | 2018-06-19 | 2019-01-01 | 福建北电新材料科技有限公司 | A kind of SiC single crystal grower improving raw material service efficiency |
CN111621851A (en) * | 2020-04-22 | 2020-09-04 | 浙江博蓝特半导体科技股份有限公司 | Silicon carbide crystal growth device and method |
CN211620664U (en) * | 2020-03-05 | 2020-10-02 | 福建北电新材料科技有限公司 | Processing apparatus for reducing corrosion of SIC gas phase substance to graphite felt heat preservation layer |
CN111748843A (en) * | 2020-07-09 | 2020-10-09 | 北京北方华创微电子装备有限公司 | Silicon carbide single crystal growth device |
CN112725817A (en) * | 2020-12-30 | 2021-04-30 | 重庆大学 | Method for preparing carbide ceramic coating by molten salt electrolysis |
CN113279030A (en) * | 2021-05-24 | 2021-08-20 | 中国人民解放军国防科技大学 | Molten salt electrodeposition method of niobium coating |
CN113584427A (en) * | 2021-07-20 | 2021-11-02 | 武汉大学 | Carbide coating based on high-melting-point metal and preparation method thereof |
-
2022
- 2022-03-01 CN CN202210191513.XA patent/CN114808068B/en active Active
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1396455A (en) * | 1972-05-04 | 1975-06-04 | Toyoda Chuo Kenkyusho Kk | Method of forming a carbide layer |
CA2330982A1 (en) * | 2001-01-15 | 2002-07-15 | Linamar Corporation | Deposition and thermal diffusion of borides and carbides of refractory metals |
CN103370764A (en) * | 2010-12-16 | 2013-10-23 | 皇家飞利浦电子股份有限公司 | Anode disk element with refractory interlayer and VPS focal track |
CN104246023A (en) * | 2012-04-20 | 2014-12-24 | 贰陆股份公司 | LARGE DIAMETER, HIGH QUALITY SiC SINGLE CRYSTALS, METHOD AND APPARATUS |
CN103014793A (en) * | 2012-12-11 | 2013-04-03 | 广东电网公司电力科学研究院 | Method for preparing titanium carbide coating through pulse electrodeposition |
CN208308999U (en) * | 2018-06-19 | 2019-01-01 | 福建北电新材料科技有限公司 | A kind of SiC single crystal grower improving raw material service efficiency |
CN211620664U (en) * | 2020-03-05 | 2020-10-02 | 福建北电新材料科技有限公司 | Processing apparatus for reducing corrosion of SIC gas phase substance to graphite felt heat preservation layer |
CN111621851A (en) * | 2020-04-22 | 2020-09-04 | 浙江博蓝特半导体科技股份有限公司 | Silicon carbide crystal growth device and method |
CN111748843A (en) * | 2020-07-09 | 2020-10-09 | 北京北方华创微电子装备有限公司 | Silicon carbide single crystal growth device |
CN112725817A (en) * | 2020-12-30 | 2021-04-30 | 重庆大学 | Method for preparing carbide ceramic coating by molten salt electrolysis |
CN113279030A (en) * | 2021-05-24 | 2021-08-20 | 中国人民解放军国防科技大学 | Molten salt electrodeposition method of niobium coating |
CN113584427A (en) * | 2021-07-20 | 2021-11-02 | 武汉大学 | Carbide coating based on high-melting-point metal and preparation method thereof |
Non-Patent Citations (1)
Title |
---|
王兴庆;王振颖;谢大海;: "烧结Nb_2O_5片制备条件对其显微结构及电脱氧性能的影响", 稀有金属与硬质合金, vol. 1, no. 03, pages 438 - 439 * |
Also Published As
Publication number | Publication date |
---|---|
CN114808068B (en) | 2024-04-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8703248B2 (en) | Polycrystalline silicon reactor | |
US7314540B2 (en) | Diamond-coated electrode and method for producing same | |
US8795506B2 (en) | Primary production of elements | |
EP2006417B1 (en) | Conductive diamond electrode structure and method for electrolytic synthesis of fluorine-containing material | |
Oishi et al. | Process for solar grade silicon production by molten salt electrolysis using aluminum-silicon liquid alloy | |
CN1382229A (en) | Amorphous metal/metallic glass electrodes for electrochemical processes | |
Zhuk et al. | Silicon electrodeposition from chloride–fluoride melts containing K2SiF6 and SiO2 | |
Lv et al. | Preparation of cohesive graphite films by electroreduction of CO32− in molten Na2CO3–NaCl | |
CN114808068A (en) | Graphite cavity inner surface treatment method, graphite cavity sheet and graphite cavity | |
JP5579634B2 (en) | Reactor for producing polycrystalline silicon and method for producing polycrystalline silicon | |
Anand et al. | Preparation of layered semiconductor (MoSe2) by electrosynthesis | |
Wang et al. | In-situ synthesis of silicide coatings on molybdenum substrates by electrodeposition in chloride-fluoride molten salts | |
JP5606976B2 (en) | Silicon ingot manufacturing apparatus and silicon ingot manufacturing method | |
CN217173945U (en) | Silicon carbide crystal growth device | |
JP4315719B2 (en) | High purity zinc production method and production equipment | |
CN102828204B (en) | Method for preparing needle-shaped silver for electrodes by electrolytic process | |
CN110670118B (en) | Crystal growth device and crystal growth method | |
CN207608603U (en) | A kind of device for handling sapphire crystallization furnace tungsten calandria and recycling metal molybdenum | |
JP2014101256A (en) | Apparatus and method for producing polycrystalline silicon rod | |
CN104884683B (en) | Method for producing SiC single crystal | |
CN102787305A (en) | Device and method for reducing impurity deposit in chemical vapor deposition process | |
CN104995135A (en) | Copper foil for graphene production, and graphene production method | |
US20080121182A1 (en) | Apparatus of supplying organometallic compound | |
US3335697A (en) | Apparatus for vapor deposition of silicon | |
JP5335074B2 (en) | Method for producing polycrystalline silicon and reactor for producing polycrystalline silicon |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |