WO2011158557A1 - 炭化珪素半導体の洗浄方法および炭化珪素半導体の洗浄装置 - Google Patents
炭化珪素半導体の洗浄方法および炭化珪素半導体の洗浄装置 Download PDFInfo
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- WO2011158557A1 WO2011158557A1 PCT/JP2011/059820 JP2011059820W WO2011158557A1 WO 2011158557 A1 WO2011158557 A1 WO 2011158557A1 JP 2011059820 W JP2011059820 W JP 2011059820W WO 2011158557 A1 WO2011158557 A1 WO 2011158557A1
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- oxide film
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- cleaning
- silicon carbide
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Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02041—Cleaning
- H01L21/02057—Cleaning during device manufacture
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02041—Cleaning
- H01L21/02043—Cleaning before device manufacture, i.e. Begin-Of-Line process
- H01L21/02046—Dry cleaning only
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02107—Forming insulating materials on a substrate
- H01L21/02225—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
- H01L21/02227—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process
- H01L21/0223—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process formation by oxidation, e.g. oxidation of the substrate
- H01L21/02233—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process formation by oxidation, e.g. oxidation of the substrate of the semiconductor substrate or a semiconductor layer
- H01L21/02236—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process formation by oxidation, e.g. oxidation of the substrate of the semiconductor substrate or a semiconductor layer group IV semiconductor
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/16—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only elements of Group IV of the Periodic Table
- H01L29/1608—Silicon carbide
Definitions
- the present invention relates to a silicon carbide (SiC) semiconductor cleaning method and a SiC semiconductor cleaning apparatus, and more particularly to a SiC semiconductor cleaning method and a SiC semiconductor cleaning apparatus used for a semiconductor device having an oxide film.
- SiC silicon carbide
- Patent Document 1 discloses that a semiconductor substrate cleaning method is performed as follows. First, a silicon (Si) substrate is washed with ultrapure water containing ozone to form a Si oxide film, and particles and metal impurities are taken into the inside and the surface of the Si oxide film. Next, the Si substrate is washed with a dilute hydrofluoric acid aqueous solution to remove the Si oxide film by etching, and at the same time, particles and metal impurities are removed.
- SiC has a large band gap, and a maximum dielectric breakdown electric field and thermal conductivity are larger than those of Si, while carrier mobility is as large as that of Si, and an electron saturation drift velocity and withstand voltage are also large. Therefore, application to a semiconductor device that is required to have high efficiency, high breakdown voltage, and large capacity is expected. Therefore, the present inventor has focused on using SiC semiconductors for semiconductor devices. When using a SiC semiconductor for a semiconductor device, it is necessary to clean the surface of the SiC semiconductor.
- the Si oxide film is formed on the SiC semiconductor and the Si oxide film is washed with a dilute hydrofluoric acid solution in order to apply the cleaning method disclosed in Patent Document 1 to the SiC semiconductor, the film quality of the Si oxide film depending on the plane orientation
- the present inventor has found that a difference occurs in the etching rate within the surface of the SiC semiconductor.
- in-plane variation occurs due to the removal of the Si oxide film in the SiC semiconductor, there may be a region where the cleaning is insufficient such as the Si oxide film remaining.
- the etching progresses only in a part of the region within the SiC semiconductor surface, thereby causing variations in the surface characteristics of the SiC semiconductor. For this reason, the surface characteristics of the SiC semiconductor after washing cannot be improved.
- an object of the present invention is to provide an SiC semiconductor cleaning method and an SiC semiconductor cleaning apparatus for cleaning an SiC semiconductor so that surface characteristics are good.
- the SiC semiconductor cleaning method of the present invention includes a step of forming an oxide film on the surface of the SiC semiconductor and a step of removing the oxide film.
- halogen plasma or hydrogen (H) plasma is used in the step of removing the oxide film. Then, the oxide film is removed.
- the SiC semiconductor cleaning method of the present invention by forming an oxide film on the surface of the SiC semiconductor, the oxide film can be formed by taking in impurities, particles, etc. adhering to the surface. Since this oxide film is removed by halogen plasma or H plasma, the influence of anisotropy due to the plane orientation of SiC can be reduced. For this reason, the oxide film formed on the surface of the SiC semiconductor can be removed so as to reduce in-plane variation. Therefore, impurities, particles, and the like on the surface of the SiC semiconductor can be removed so as to reduce in-plane variation. In addition, since the SiC semiconductor is a stable compound, even if halogen plasma is used, the damage to the SiC semiconductor is small. Therefore, the SiC semiconductor can be cleaned so that the surface characteristics are good.
- fluorine (F) plasma is used as the halogen plasma in the step of removing the oxide film.
- F plasma has high etching efficiency and low possibility of metal contamination. For this reason, a SiC semiconductor can be washed so that surface characteristics may become better.
- the oxide film is removed at a temperature of 20 ° C. or higher and 400 ° C. or lower.
- the oxide film is removed at a pressure of 0.1 Pa to 20 Pa.
- the reactivity between the halogen plasma or H plasma and the oxide film can be increased, so that the oxide film can be easily removed.
- oxygen (O) plasma is preferably used in the step of forming the oxide film.
- an oxide film can be easily formed on the surface of a SiC semiconductor which is a strong compound and has a strong bond. Therefore, it is possible to easily form an oxide film by taking in impurities, particles, and the like attached to the surface. By removing this oxide film with halogen plasma, impurities, particles and the like on the surface of the SiC semiconductor can be removed. Further, since the SiC semiconductor is a stable compound, even if O plasma is used, there is little damage to the SiC semiconductor. Therefore, the SiC semiconductor can be cleaned so that the surface characteristics are better.
- the SiC semiconductor is preferably disposed in an atmosphere cut off from the atmosphere between the step of forming the oxide film and the step of removing the oxide film.
- the SiC semiconductor can be cleaned so as to have better surface characteristics.
- the SiC semiconductor cleaning device includes a forming unit, a removing unit, and a connecting unit.
- the forming unit forms an oxide film on the surface of the SiC semiconductor.
- the removing unit removes the oxide film using halogen plasma or H plasma.
- the connecting part connects the forming part and the removing part so that the SiC semiconductor can be transported. The region for transporting the SiC semiconductor in the connecting portion can be cut off from the atmosphere.
- a SiC semiconductor cleaning apparatus includes a forming unit for forming an oxide film on a surface of the SiC semiconductor, and a removing unit for removing the oxide film using halogen plasma or H plasma.
- the forming part and the removing part are the same.
- the SiC semiconductor cleaning apparatus in one and other aspects of the present invention, after forming the oxide film on the SiC semiconductor in the forming unit, the SiC semiconductor is exposed to the atmosphere while the oxide film is removed in the removing unit. This can be suppressed. Thereby, it can suppress that the impurity in air
- the oxide film incorporating impurities, particles and the like is removed by halogen plasma or H plasma, the influence of anisotropy due to the plane orientation of SiC can be reduced. Thereby, the oxide film formed on the surface of the SiC semiconductor can be removed so as to reduce in-plane variation. Therefore, the SiC semiconductor can be cleaned so that the surface characteristics are good.
- the SiC semiconductor is formed so that the surface characteristics are improved by removing the oxide film formed on the surface with halogen plasma or H plasma. Can be washed.
- FIG. 1 is a schematic diagram of a SiC semiconductor cleaning apparatus according to Embodiment 1 of the present invention. With reference to FIG. 1, a SiC semiconductor cleaning apparatus according to an embodiment of the present invention will be described.
- the SiC semiconductor cleaning apparatus 10 includes a forming unit 11, a removing unit 12, and a connecting unit 13.
- the formation part 11 and the removal part 12 are connected by a connection part 13.
- the inside of the formation part 11, the removal part 12, and the connection part 13 is interrupted
- the forming unit 11 forms an oxide film on the surface of the SiC semiconductor.
- a plasma generator an apparatus for forming an oxide film using a solution containing O such as ozone water, or the like is used.
- the removal unit 12 removes the oxide film formed by the formation unit 11.
- a plasma generator is used as the removing unit 12.
- the removing unit 12 removes the oxide film using halogen plasma or hydrogen plasma.
- the plasma generator used in the forming unit 11 and the removing unit 12 is not particularly limited.
- a parallel plate RIE (Reactive Ion Etching) device, an ICP (Inductive Coupled Plasma) RIE device, An ECR (Electron Cyclotron Resonance) type RIE apparatus, an SWP (Surface Wave Plasma) type RIE apparatus, a CVD (Chemical Vapor Deposition) apparatus, or the like is used.
- the connecting unit 13 connects the forming unit 11 and the removing unit 12 so that the SiC substrate 1 can be transported. A region (internal space) for transporting SiC substrate 1 in connecting portion 13 can be blocked from the atmosphere.
- the shielding from the atmosphere means an atmosphere in which the atmosphere is not mixed, for example, in a vacuum or an atmosphere made of inert gas or nitrogen gas.
- the atmosphere cut off from the atmosphere is, for example, in a vacuum, or nitrogen (N), helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon. (Rn) or an atmosphere filled with a gas composed of a combination thereof.
- connection unit 13 connects the inside of the forming portion 11 and the inside of the removing portion 12.
- Connection unit 13 has a space for transporting the SiC semiconductor unloaded from forming unit 11 to removal unit 12. That is, the connection part 13 is installed in order to convey the SiC semiconductor from the formation part 11 to the removal part 12 so that it may not be opened to the atmosphere.
- the connecting portion 13 has such a size that the SiC substrate 1 can be transported inside.
- Connection portion 13 may have a size that can be transported in a state where SiC substrate 1 is placed on a susceptor.
- the connection part 13 is a load lock chamber which connects the exit of the formation part 11 and the entrance of the removal part 12, for example.
- the cleaning apparatus 10 may further include a first transport unit that is disposed inside the connection unit 13 and transports the SiC semiconductor from the formation unit 11 to the removal unit 12.
- the cleaning apparatus 10 takes out the SiC semiconductor from which the oxide film has been removed by the removing unit 12 to the outside of the cleaning apparatus 10, or an atmosphere that is shut off from the atmosphere to the oxide film forming unit that forms the oxide film constituting the semiconductor device. You may further provide the 2nd conveyance part for conveying within.
- the first transport unit and the second transport unit may be the same or different.
- the cleaning apparatus 10 may further include a blocking unit that is disposed between the forming unit 11 and the connecting unit 13 and that blocks the inside of the forming unit 11 and the inside of the connecting unit 13.
- the cleaning device 10 may further include a blocking unit that is disposed between the removing unit 12 and the connecting unit 13 and that blocks the inside of the removing unit 12 and the inside of the connecting unit 13.
- the blocking unit for example, a valve or a door that can block each communication unit can be used.
- the cleaning apparatus 10 may further include a vacuum pump for discharging the internal atmospheric gas and a replacement gas cylinder for replacing the internal atmospheric gas.
- the vacuum pump and the replacement gas cylinder may be connected to each of the forming unit 11, the removing unit 12, and the connecting unit 13, or may be connected to at least one of them.
- cleaning apparatus 10 may contain various elements other than the above, illustration and description of these elements are abbreviate
- connection portion 13 the shape of connecting only the formation portion 11 and the removal portion 12 as the connection portion 13 is shown, but the shape is not particularly limited thereto.
- a chamber in which the atmosphere is shut off may be used as the connection unit 13, and the formation unit 11 and the removal unit 12 may be disposed in the chamber.
- FIG. 2 is a cross-sectional view schematically showing a SiC semiconductor prepared in the first embodiment of the present invention.
- FIG. 3 is a flowchart showing the SiC semiconductor cleaning method according to the first embodiment of the present invention.
- FIG. 4 is a cross sectional view schematically showing a state where an oxide film is formed on the SiC semiconductor in the first embodiment of the present invention.
- FIG. 5 is a cross sectional view schematically showing a state where the oxide film is removed in the first embodiment of the present invention.
- a method of cleaning an SiC semiconductor according to an embodiment of the present invention will be described with reference to FIGS.
- a method of cleaning SiC substrate 1 shown in FIG. 2 as an SiC semiconductor will be described.
- SiC semiconductor cleaning apparatus 10 shown in FIG. 1 is used.
- SiC substrate 1 having a surface 1a is prepared (step S1).
- SiC substrate 1 is not particularly limited, but can be prepared, for example, by the following method.
- HVPE Hydride Vapor Phase Epitaxy
- MBE Molecular Beam Epitaxy
- OMVPE Organic Vapor Phase Epitaxy
- sublimation method A SiC ingot grown by a vapor phase growth method such as a CVD method, a liquid phase growth method such as a flux method or a high nitrogen pressure solution method is prepared. Thereafter, a SiC substrate having a surface is cut out from the SiC ingot.
- the cutting method is not particularly limited, and the SiC substrate is cut from the SiC ingot by slicing or the like. Next, the cut surface of the SiC substrate is polished.
- the surface to be polished may be only the front surface, or the back surface opposite to the front surface may be further polished.
- the method of polishing is not particularly limited, but, for example, CMP (Chemical Mechanical Polishing) is employed in order to flatten the surface and reduce damage such as scratches.
- CMP Chemical Mechanical Polishing
- colloidal silica is used as an abrasive, diamond
- chromium oxide is used as abrasive grains
- an adhesive, wax, or the like is used as a fixing agent.
- other polishing such as an electric field polishing method, a chemical polishing method, and a mechanical polishing method may be further performed. Polishing may be omitted.
- SiC substrate 1 having surface 1a shown in FIG. 2 can be prepared.
- As such SiC substrate 1 for example, a substrate having an n-type conductivity and a resistance of 0.02 ⁇ cm is used.
- oxide film 3 is formed on surface 1a of SiC substrate 1 (step S2).
- the oxide film 3 is formed by the forming unit 11 of the cleaning apparatus 10 shown in FIG.
- the method of forming oxide film 3 is not particularly limited, and examples thereof include a method of oxidizing surface 1a of SiC substrate 1 using a solution containing O, O plasma, thermal oxidation in an atmosphere containing O gas, or the like.
- Examples of the solution containing O include ozone water. Considering that SiC is a stable compound, it is preferable to use ozone water having a concentration of, for example, 30 ppm or more. In this case, the decomposition of ozone can be suppressed and the reaction rate between the surface 1a and ozone can be increased, so that the oxide film 3 can be easily formed on the surface 1a.
- thermal oxidation including O gas is preferably performed, for example, in a dry atmosphere at a temperature of 700 ° C. or higher.
- the dry atmosphere means that the oxide film 3 is formed in the gas phase, and may include an unintended liquid phase component.
- the O plasma means plasma generated from a gas containing O element, and can be generated by supplying O gas to a plasma generator, for example.
- Oxide film 3 is formed by O plasma means that oxide film 3 is formed by plasma using a gas containing an O element. In other words, it means that the oxide film 3 is formed by processing with plasma generated from a gas containing O element.
- the oxide film 3 is preferably formed at 200 ° C. or higher and 700 ° C. or lower. In this case, the oxide film 3 can be formed with improved throughput. Moreover, since electric power can be reduced, the oxide film 3 can be formed at a reduced cost. In addition, an oxide film can be formed uniformly.
- step S2 When using O plasma in step S2, an oxide film is formed in an atmosphere of 0.1 Pa or more and 20 Pa or less. In this case, the reactivity with the surface 1a of the SiC substrate 1 can be increased.
- step S2 an oxide film 3 having a thickness of, for example, one molecular layer or more and 30 nm or less is formed.
- the oxide film 3 having a thickness of one molecular layer or more impurities, particles and the like on the surface 1a can be taken into the oxide film.
- an oxide film of 30 nm or less the oxide film 3 is easily removed in step S3 described later.
- the oxide film 3 is, for example, silicon oxide.
- SiC substrate 1 on which oxide film 3 is formed by forming unit 11 is transferred to removing unit 12.
- the SiC substrate 1 is transported in the connection portion 13 which is an atmosphere cut off from the atmosphere.
- SiC substrate 1 is placed in an atmosphere cut off from the atmosphere. Thereby, after oxide film 3 is formed, it can control that impurities contained in the atmosphere adhere to SiC substrate 1.
- step S3 the oxide film 3 is removed.
- the oxide film 3 is removed by halogen plasma or H plasma.
- the oxide film 3 is removed by the removing unit 12 of the cleaning apparatus 10 shown in FIG.
- the halogen plasma means plasma generated from a gas containing a halogen element.
- the halogen element is F, chlorine (Cl), bromine (Br), and iodine (I).
- “Removing the oxide film 3 with halogen plasma” means that the oxide film 3 is etched with plasma using a gas containing a halogen element. In other words, it means that the oxide film 3 is removed by processing with plasma generated from a gas containing a halogen element.
- the F plasma means plasma generated from a gas containing F element.
- F element For example, carbon tetrafluoride (CF 4), trifluoromethane (CHF 3 ), chlorofluorocarbon (C 2 F 6 ), hexafluoride.
- Plasma generator using single gas or mixed gas of sulfur fluoride (SF 6 ), nitrogen trifluoride (NF 3 ), xenon difluoride (XeF 2 ), fluorine (F 2 ), and chlorine trifluoride (ClF 3 ) Can be generated by supplying to “Removing the oxide film 3 by F plasma” means that the oxide film 3 is etched by plasma using a gas containing an F element. In other words, it means that the oxide film 3 is removed by processing with plasma generated from a gas containing F element.
- H plasma means plasma generated from a gas containing H element, and can be generated, for example, by supplying H 2 gas to a plasma generator. “Removing the oxide film 3 with H plasma” means that the oxide film 3 is etched with plasma using a gas containing H element. In other words, it means that the oxide film 3 is removed by processing with plasma generated from a gas containing H element.
- this step S3 it is preferable to remove the oxide film 3 at a temperature of 20 ° C. or higher and 400 ° C. or lower.
- this step S3 it is preferable to remove the oxide film 3 at a pressure of 0.1 Pa or more and 20 Pa or less.
- step S3 When step S3 is performed, the oxide film that has taken in impurities, particles, and the like in step S2 can be removed, so that impurities, particles, and the like that have adhered to the surface 1a of the SiC substrate 1 prepared in step S1 can be removed. .
- step S1 to S3 SiC substrate 2 having surface 2a with reduced impurities and particles can be realized.
- steps S2 and S3 may be repeated. Further, after step S1, a cleaning process with another chemical solution, a pure water rinsing process, a drying process, and the like may be additionally performed as necessary. Examples of the other chemical liquid include SPM containing sulfuric acid and hydrogen peroxide solution. When washing with SPM before step S2, organic substances can be removed. Further, RCA cleaning or the like may be performed before step S2.
- the cleaning method of SiC substrate 1 as the SiC semiconductor in the present embodiment includes the step of forming oxide film 3 on surface 1a of SiC substrate 1 (step S2) and the step of removing oxide film 3 In the step of removing (Step S3), the oxide film 3 is removed by halogen plasma or H plasma.
- step S2 by forming the oxide film 3 on the surface 1a of the SiC substrate 1, the metal film such as titanium (Ti), particles, etc. adhering to the surface 1a can be taken in and the oxide film 3 can be formed. Since the oxide film 3 is removed by using active halogen by halogen plasma or active H by H plasma, the influence of anisotropy due to the plane orientation of SiC can be reduced. Therefore, oxide film 3 formed on surface 1a of SiC substrate 1 can be removed so as to reduce in-plane variation. That is, the oxide film 3 can be removed with good uniformity without being affected by the film quality of the oxide film 3. Therefore, impurities, particles, and the like on surface 1a of SiC substrate 1 can be removed so as to reduce in-plane variation.
- the present inventors pay attention to the fact that the SiC substrate is chemically stable. Even if the method of removing the oxide film 3 by halogen plasma or H plasma, which causes damage to the Si substrate, is applied to the SiC substrate, It has been found that the substrate 1 is hardly damaged. For this reason, even if halogen plasma or H plasma is used in step S3, damage to SiC substrate 1 is small.
- SiC substrate 1 can be cleaned so that the surface characteristics are good.
- step S3 the oxide film 3 is removed by halogen plasma or H plasma in a dry atmosphere.
- the plasma is clean and environmentally friendly.
- the plasma etching step can omit post-treatment such as water washing and drying as compared with washing in a wet atmosphere (atmosphere including a liquid phase), SiC substrate 1 can be easily washed.
- there is no need for post-treatment with water it is possible to suppress the occurrence of a watermark on the surface 2a of the SiC substrate 2 after step S3.
- O plasma is preferably used in the step of forming oxide film 3 (step S2).
- the present inventor has paid attention to the fact that when the cleaning method of Patent Document 1 is applied to a SiC semiconductor, SiC is a thermally stable compound than Si, so that the surface of the SiC semiconductor is hardly oxidized. That is, the cleaning method of Patent Document 1 can oxidize the surface of Si, but cannot sufficiently oxidize the surface of SiC, and thus cannot sufficiently clean the surface of the SiC semiconductor. Therefore, as a result of intensive studies by the present inventors in order to oxidize the surface of the SiC semiconductor, it has been found that the oxide film 3 can be easily formed by using active O by using O plasma. Further, since SiC is strong in terms of crystal, even if O plasma is used, damage to the SiC substrate 1 is small. Therefore, SiC substrate 1 can be cleaned so as to have better surface characteristics.
- an oxide film 3 is formed on the surface 1a of the SiC substrate 1 by O plasma (step S2), and the oxide film 3 is removed by halogen plasma or H plasma (step S3), thereby enabling a dry atmosphere (in the gas phase).
- the surface 1a of the SiC substrate 1 can be cleaned.
- metal ions may be contained in the liquid phase, instruments, and the like used for cleaning.
- particles tend to increase from the cleaning chamber. For this reason, cleaning in a dry atmosphere can reduce metal impurities and particles on the surface more than in a wet atmosphere (an atmosphere containing a liquid phase).
- a cleaning apparatus 10 for SiC substrate 1 as an SiC semiconductor in an embodiment of the present invention includes a formation portion 11 for forming oxide film 3 on surface 1a of SiC substrate 1, and an oxide film using halogen plasma or H plasma. 3 and a connecting portion 13 that connects the forming portion 11 and the removing portion 12 so that the SiC substrate can be transported, and the region in which the SiC substrate 1 is transported can be blocked from the atmosphere. It has.
- SiC substrate 1 is removed from atmosphere while removing oxide film 3 in removing unit 12. It can suppress exposure to. Thereby, it can suppress that the impurity in air
- FIG. 10 since the oxide film 3 incorporating impurities, particles, and the like is removed by halogen plasma or H plasma, the influence of anisotropy due to the plane orientation of SiC can be reduced. Thereby, oxide film 3 formed on surface 1a of SiC substrate 1 can be removed so as to reduce in-plane variation. Therefore, SiC substrate 1 can be cleaned so that the surface characteristics are good.
- FIG. 6 is a schematic diagram of a SiC semiconductor cleaning apparatus according to a modification of the first embodiment of the present invention. With reference to FIG. 6, a SiC semiconductor cleaning apparatus in a modification of the present embodiment will be described.
- the cleaning device 20 includes a chamber 21, a first gas supply unit 22, a second gas supply unit 23, and a vacuum pump 24.
- the first gas supply unit 22, the second gas supply unit 23, and the vacuum pump 24 are connected to the chamber 21.
- the chamber 21 is a plasma generator that houses the SiC substrate 1 therein.
- a parallel plate type RIE apparatus an ICP type RIE apparatus, an ECR type RIE apparatus, a SWP type RIE apparatus, a CVD apparatus, or the like is used.
- the first and second gas supply units 22 and 23 supply the gas of the plasma generation source to the chamber 21.
- the first gas supply unit 22 supplies a gas containing, for example, O.
- the first gas supply unit 22 can generate O plasma in the chamber 21, whereby the oxide film 3 can be formed on the surface 1 a of the SiC substrate 1.
- the second gas supply unit 23 supplies a gas containing, for example, halogen or H. Therefore, the second gas supply unit 23 can generate halogen plasma or H plasma in the chamber 21, thereby removing the oxide film 3 formed on the surface 1 a of the SiC substrate 1. it can.
- the vacuum pump 24 evacuates the inside of the chamber 21. Therefore, after forming oxide film 3 on surface 1a of SiC substrate 1 by O plasma, the inside of chamber 21 can be evacuated and oxide film 3 can be removed by halogen plasma or H plasma.
- the vacuum pump 24 may be omitted.
- the cleaning apparatus shown in FIG. 6 may include various elements other than those described above, but the illustration and description of these elements are omitted for convenience of description.
- SiC semiconductor cleaning apparatus 20 in the modification of the present embodiment uses a formation portion for forming oxide film 3 on surface 1a of SiC substrate 1 as the SiC semiconductor, and halogen plasma or H plasma.
- the removal part for removing the oxide film 3 is provided, and the formation part and the removal part are the same (chamber 21).
- the SiC semiconductor cleaning apparatus 20 in the modified example it is not necessary to transport the SiC substrate 1 while the oxide film 3 is formed on the SiC substrate 1 in the forming unit and then the oxide film 3 is removed in the removing unit.
- the SiC substrate 1 is not exposed to the atmosphere.
- the SiC substrate is placed in an atmosphere cut off from the atmosphere. Thereby, it is possible to prevent impurities in the atmosphere from reattaching to surface 1 a of SiC substrate 1 during cleaning of SiC substrate 1.
- oxide film 3 incorporating impurities, particles, and the like is removed by halogen plasma or H plasma, the influence of anisotropy due to the plane orientation of SiC can be reduced. Thereby, oxide film 3 formed on surface 1a of SiC substrate 1 can be removed so as to reduce in-plane variation. Therefore, SiC substrate 1 can be cleaned so that the surface characteristics are good.
- FIG. 7 is a cross sectional view schematically showing an SiC semiconductor to be cleaned in the second embodiment of the present invention.
- FIG. 8 is a flowchart showing a method of cleaning an SiC semiconductor in the second embodiment of the present invention.
- 9 to 11 are cross sectional views schematically showing one step of the SiC semiconductor cleaning method in the second embodiment of the present invention.
- the SiC semiconductor cleaning method in the present embodiment will be described with reference to FIGS. 2, 4, 5, and 7 to 11.
- FIG. In the present embodiment, a method of cleaning an epitaxial wafer 100 including a SiC substrate 2 and an epitaxial layer 120 formed on the SiC substrate 2 will be described as a SiC semiconductor, as shown in FIG.
- Step S1 is the same as that in the first embodiment, and therefore description thereof will not be repeated.
- oxide film 3 is formed on surface 1a of SiC substrate 1 (step S2), and thereafter, oxide film 3 is removed as shown in FIGS. Step S3). Since steps S2 and S3 are the same as in the first embodiment, description thereof will not be repeated. Thereby, surface 1a of SiC substrate 1 can be cleaned, and SiC substrate 2 having surface 2a with reduced impurities and particles can be prepared. Cleaning of surface 1a of SiC substrate 1 may be omitted.
- an epitaxial layer 120 is formed on the surface 2a of the SiC substrate 2 by a vapor phase growth method, a liquid phase growth method, or the like (step S4).
- epitaxial layer 120 is formed as follows, for example.
- buffer layer 121 is formed on surface 2 a of SiC substrate 2.
- Buffer layer 121 is an epitaxial layer made of, for example, n-type SiC and having a thickness of 0.5 ⁇ m, for example.
- the concentration of conductive impurities in the buffer layer 121 is, for example, 5 ⁇ 10 17 cm ⁇ 3 .
- a breakdown voltage holding layer 122 is formed on the buffer layer 121.
- a layer made of SiC of n-type conductivity is formed by a vapor phase growth method, a liquid phase growth method, or the like.
- the thickness of the breakdown voltage holding layer 122 is, for example, 15 ⁇ m.
- the concentration of the n-type conductive impurity in the breakdown voltage holding layer 122 is, for example, 5 ⁇ 10 15 cm ⁇ 3 .
- a p-type well region 123, an n + source region 124, and a p + contact region 125 are formed as follows. First, a well region 123 is formed by selectively injecting p-type impurities into a part of the breakdown voltage holding layer 122. Thereafter, a source region 124 is formed by selectively injecting an n-type conductive impurity into a predetermined region, and a contact is formed by selectively injecting a p-type conductive impurity into the predetermined region. Region 125 is formed. The impurity is selectively implanted using a mask made of an oxide film, for example. This mask is removed after the implantation of impurities.
- Activating annealing treatment may be performed after such an implantation step.
- annealing is performed in an argon atmosphere at a heating temperature of 1700 ° C. for 30 minutes.
- an epitaxial wafer 100 including SiC substrate 2 and epitaxial layer 120 formed on SiC substrate 2 can be prepared.
- the surface 100a of the epitaxial wafer 100 is cleaned. Specifically, as shown in FIGS. 8 and 10, the oxide film 3 is formed on the surface 100a of the epitaxial wafer 100 (step S2).
- This step S2 is the same as step S2 in which oxide film 3 is formed on surface 1a of SiC substrate 1 in the first embodiment.
- the damaged layer may be oxidized for the purpose of removing the damaged layer.
- the surface is oxidized from the surface 100a toward the SiC substrate 2 by more than 10 nm and not more than 100 nm by, for example, O plasma or thermal oxidation at 1100 ° C. or higher.
- step S3 the oxide film 3 formed on the surface 100a of the epitaxial wafer 100 is removed by halogen plasma or H plasma (step S3). Since step S3 is similar to step S3 for removing oxide film 3 formed on surface 1a of SiC substrate 1 in the first embodiment, description thereof will not be repeated.
- step S2 and step S3 may be repeated, and another cleaning process may be further included, as in the first embodiment.
- an epitaxial wafer 101 having a surface 101a with reduced impurities and particles can be realized.
- connection part 13 has the shape which can convey the epitaxial wafer 100 or the susceptor in which the epitaxial wafer 100 was mounted.
- oxide film 3 is generated by halogen plasma or H plasma that cannot be adopted by Si due to damage. Has been removed. Since the halogen plasma and the H plasma are clean and highly uniform, the influence of anisotropy due to the plane orientation can be reduced and the oxide film 3 can be removed. Therefore, the surface of the epitaxial wafer 100 can be cleaned so as to have good characteristics.
- epitaxial wafer 101 having surface 101a with reduced impurities, particles, etc. can be manufactured as shown in FIG.
- an insulating film constituting a semiconductor device such as a gate oxide film
- the characteristics of the insulating film can be improved, and the interface between the surface 101a and the insulating film, and impurities, particles, etc. present in the insulating film Can be reduced. Therefore, it is possible to improve the breakdown voltage when applying the reverse voltage to the semiconductor device, and to improve the stability and long-term reliability of the operation when applying the forward voltage. Therefore, the SiC semiconductor cleaning method of the present invention is particularly preferably used for the surface 100a of the epitaxial wafer 100 before the gate oxide film is formed.
- the epitaxial wafer 101 cleaned by the cleaning method of the present embodiment can improve the characteristics of the insulating film by forming an insulating film on the cleaned surface 101a. Therefore, the epitaxial wafer 101 is preferably used for a semiconductor device having an insulating film. it can. Accordingly, the epitaxial wafer 101 cleaned in the present embodiment has an insulated gate field effect portion such as a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) or an IGBT (Insulated Gate Bipolar Transistor). It can be suitably used for a semiconductor device or a JFET (Junction Field-Effect Transistor).
- MOSFET Metal Oxide Semiconductor Field Effect Transistor
- IGBT Insulated Gate Bipolar Transistor
- SiC substrate 2 and SiC epitaxial layer 120 formed on SiC substrate 2 are provided, and SiC epitaxial layer 120 has a method for cleaning surface 100a of epitaxial wafer 100 having ion-implanted surface 100a.
- the cleaning method of the present invention can also be applied to a SiC epitaxial layer having a surface that is not ion-implanted.
- cleaning epitaxial wafer 100 at least one of surface 2a of SiC substrate 2 constituting epitaxial wafer 100 or surface 100a of epitaxial wafer 100 may be cleaned.
- the SiC semiconductor cleaning method of the present invention is for (i) cleaning an SiC substrate and (ii) cleaning an epitaxial wafer having an SiC substrate and an SiC epitaxial layer formed on the SiC substrate.
- the SiC epitaxial layer of (ii) includes one that is ion-implanted from the surface and one that is not ion-implanted.
- FIG. 12 is a cross-sectional view schematically showing an epitaxial wafer 130 to be cleaned in the embodiment.
- a p-type SiC layer 131 having a thickness of 10 ⁇ m and an impurity concentration of 1 ⁇ 10 16 cm ⁇ 3 was grown by the CVD method (step S4).
- a source region 124 and a drain region 129 having an impurity concentration of 1 ⁇ 10 19 cm ⁇ 3 were formed using phosphorus (P) as an n-type impurity by using SiO 2 as a mask. Also, A contact region 125 having an impurity concentration of 1 ⁇ 10 19 cm ⁇ 3 is formed using aluminum (Al) as a p-type impurity (step S5). Note that the mask was removed after each ion implantation.
- activation annealing treatment was performed.
- Ar gas was used as the atmosphere gas, and the heating temperature was 1700 to 1800 ° C. and the heating time was 30 minutes.
- an epitaxial wafer 130 having a surface 130a was prepared. Subsequently, the surface 130a of the epitaxial wafer 130 was cleaned using the cleaning apparatus 20 shown in FIG.
- step S2 An oxide film was formed using O plasma (step S2).
- the epitaxial wafer 130 was placed inside the chamber 21 using the parallel plate RIE cleaning apparatus 20 shown in FIG. 6, and O plasma treatment was performed under the following conditions.
- O 2 gas is supplied from the first gas supply unit 22 at 50 sccm
- the pressure of the atmosphere in the chamber 21 is 1.0 Pa
- the heating temperature of the back surface of the SiC substrate 2 in the epitaxial wafer 130 is 400 ° C.
- the power is 500 W.
- An oxide film was formed with (power) applied. This confirmed that an oxide film having a thickness of 1 nm could be formed on the surface 130a of the epitaxial wafer 130.
- step S3 the oxide film was removed using F plasma with the epitaxial wafer 130 disposed in the chamber 21 (step S3).
- step S3 supply of O from the first gas supply unit 22 is stopped, and F 2 gas is supplied from the second gas supply unit 23 to 30 sccm.
- the oxide film is removed in a state where the pressure of the atmosphere in the chamber 21 is 1.0 Pa, the heating temperature of the back surface of the SiC substrate 2 in the epitaxial wafer 130 is 400 ° C., and power of 300 W is applied. did. This confirmed that the oxide film formed in step S2 could be removed uniformly (with reduced in-plane variation).
- the surface 130a of the epitaxial wafer 130 was cleaned by the above processes (Steps S1 to S5).
- the surface of the epitaxial wafer 130 after the cleaning in Example 1 of the present invention had less impurities and particles than the surface 130a before the cleaning.
- no oxide film remained locally on the surface of the epitaxial wafer 130 after the cleaning in Example 1 of the present invention.
- Comparative Example 1 In Comparative Example 1, first, an epitaxial wafer 130 shown in FIG. 12 similar to Example 1 of the present invention was prepared.
- the method for cleaning the epitaxial wafer 130 of Comparative Example 1 was basically the same as the method for cleaning the epitaxial wafer 130 of Example 1 of the present invention, but HF was used instead of F plasma in step S3 for removing the oxide film. And the point that the cleaning device 10 shown in FIG. 1 was used instead of the cleaning device 20 shown in FIG.
- an oxide film was formed on the surface 130a of the prepared epitaxial wafer 130 using O plasma in the cleaning apparatus 20 shown in FIG. 1 (step S2).
- a parallel plate RIE was used as the formation part 11, the epitaxial wafer 130 was arranged inside the formation part 11, and O plasma was performed under the following conditions similar to Example 1 of the present invention.
- O 2 gas is supplied at 50 sccm, and the pressure of the atmosphere in the formation portion 11 is 1.0 P.
- the heating temperature of the back surface of the SiC substrate 2 in the epitaxial wafer 130 was set to 400 ° C., and an electric power of 500 W was applied to form an oxide film. This confirmed that an oxide film having a thickness of 1 nm could be formed on the surface 130a of the epitaxial wafer 130.
- the epitaxial wafer 130 on which the oxide film was formed in the formation unit 11 was transferred to the removal unit 12. At this time, the epitaxial wafer 130 was transferred in the connection part 13 which is an atmosphere cut off from the atmosphere.
- the oxide film was removed using HF.
- the oxide film 3 was removed by storing HF in the removal portion 12 and immersing the epitaxial wafer 130 in HF.
- the epitaxial wafer 130 was taken out from the cleaning apparatus 10 and the surface of the epitaxial wafer 130 was cleaned with pure water (pure water rinsing step). Next, the epitaxial wafer 130 was dried by a spin method (drying process).
- step S2 the above-described step of forming an oxide film using O plasma (step S2), the step of removing the oxide film using HF, the pure water rinsing step, and the drying step were repeated.
- the surface 130a of the epitaxial wafer 130 was cleaned through the above steps.
- the oxide film formed in Step S2 could not be removed more uniformly (with reduced in-plane variation) than in Inventive Example 1. This is because, in Comparative Example 1, since the oxide film was removed using HF, due to the film quality of the oxide film depending on the plane orientation, there was an in-plane variation in the removal of the oxide film due to the difference in the etching rate within the plane of the epitaxial wafer 130. This is thought to have occurred.
- an oxide film is formed on the surface of the SiC semiconductor, and this oxide film is removed using halogen plasma, so that impurities, particles, etc. attached to the surface can be removed in-plane. It was found that the SiC semiconductor can be cleaned with good surface characteristics because it can be removed to reduce variation.
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Abstract
Description
ので、SiCの面方位による異方性の影響を低減できる。このため、SiC半導体の表面に形成した酸化膜を、面内バラツキを低減するように除去することができる。したがって、SiC半導体の表面の不純物、パーティクルなどを、面内バラツキを低減するように除去することができる。また、SiC半導体は、安定な化合物であるので、ハロゲンプラズマを用いても、SiC半導体へのダメージが少ない。よって、表面特性が良好になるように、SiC半導体を洗浄することができる。
上記SiC半導体の洗浄方法において好ましくは、酸化膜を除去する工程では、酸化膜の除去を0.1Pa以上20Pa以下の圧力で行なう。
図1は、本発明の実施の形態1におけるSiC半導体の洗浄装置の模式図である。図1を参照して、本発明の一実施の形態におけるSiC半導体の洗浄装置を説明する。
気ガスを置換するための置換ガスボンベをさらに備えていてもよい。真空ポンプや置換ガスボンベは、形成部11、除去部12および接続部13のそれぞれに接続されていてもよく、少なくともいずれか1つに接続されていてもよい。
を考慮すると、たとえば30ppm以上の濃度を有するオゾン水を用いることが好ましい。この場合、オゾンの分解を抑制できるとともに、表面1aとオゾンとの反応速度を高めることができるので、表面1aに酸化膜3を容易に形成することができる。
ることを意味する。
窒素(NF3)、二フッ化キセノン(XeF2)、フッ素(F2)、および三フッ化塩素(ClF3)の単独ガスあるいは混合ガスをプラズマ発生装置に供給することにより発生させることができる。「Fプラズマにより酸化膜3を除去する」とは、F元素を含むガスを用いたプラズマにより酸化膜3をエッチングすることを意味する。言い換えると、F元素を含むガスから生成されるプラズマによって処理されることにより、酸化膜3を除去することを意味する。
スをプラズマ発生装置に供給することにより発生させることができる。「Hプラズマにより酸化膜3を除去する」とは、H元素を含むガスを用いたプラズマにより酸化膜3をエッチングすることを意味する。言い換えると、H元素を含むガスから生成されるプラズマによって処理されることにより、酸化膜3を除去することを意味する。
図6は、本発明の実施の形態1の変形例におけるSiC半導体の洗浄装置の模式図である。図6を参照して、本実施の形態の変形例におけるSiC半導体の洗浄装置を説明する。
図7は、本発明の実施の形態2における洗浄するSiC半導体を概略的に示す断面図である。図8は、本発明の実施の形態2におけるSiC半導体の洗浄方法を示すフローチャートである。図9~図11は、本発明の実施の形態2におけるSiC半導体の洗浄方法の一工程を概略的に示す断面図である。図2、図4、図5、図7~図11を参照して、本実施の形態におけるSiC半導体の洗浄方法について説明する。本実施の形態では、SiC半導体として、図7に示すように、SiC基板2と、SiC基板2上に形成されたエピタキシャル層120とを含むエピタキシャルウエハ100を洗浄する方法を説明する。
ス領域124と、p+コンタクト領域125とを、以下のように形成する。まず導電型が
p型の不純物を耐圧保持層122の一部に選択的に注入することで、ウエル領域123を形成する。その後、n型の導電性不純物を所定の領域に選択的に注入することによってソース領域124を形成し、また導電型がp型の導電性不純物を所定の領域に選択的に注入することによってコンタクト領域125を形成する。なお不純物の選択的な注入は、たとえば酸化膜からなるマスクを用いて行われる。このマスクは、不純物の注入後にそれぞれ除去される。
まず、SiC基板2として、表面2aを有する4H-SiC基板を準備した(ステップS1)。
アルミニウム(Al)をp型不純物として1×1019cm-3の不純物濃度を有するコンタクト領域125を形成した(ステップS5)。なお、各々のイオン注入をした後には、マスクを除去した。
6に示す平行平板型RIEの洗浄装置20を用い、チャンバ21の内部にエピタキシャルウエハ130を配置し、以下の条件でOプラズマ処理を行なった。第1のガス供給部22からO2ガスを50sccmで供給し、チャンバ21内の雰囲気の圧力が1.0Paで、エピタキシャルウエハ130におけるSiC基板2の裏面の加熱温度を400℃とし、500Wの電力(パワー)を印加した状態で、酸化膜を形成した。これにより、エピタキシャルウエハ130の表面130aに1nmの厚みの酸化膜を形成できたことを確認した。
で供給し、チャンバ21内の雰囲気の圧力が1.0Paで、エピタキシャルウエハ130におけるSiC基板2の裏面の加熱温度を400℃とし、300Wの電力(パワー)を印加した状態で、酸化膜を除去した。これにより、ステップS2で形成した酸化膜が均一に(面内バラツキを低減して)除去できたことを確認した。
比較例1においては、まず、本発明例1と同様の図12に示すエピタキシャルウエハ130を準備した。
aで、エピタキシャルウエハ130におけるSiC基板2の裏面の加熱温度を400℃とし、500Wの電力(パワー)を印加した状態で、酸化膜を形成した。これにより、エピタキシャルウエハ130の表面130aに1nmの厚みの酸化膜を形成できたことを確認した。
Claims (8)
- 炭化珪素半導体(1)の表面に酸化膜(3)を形成する工程と、
前記酸化膜(3)を除去する工程とを備え、
前記酸化膜(3)を除去する工程では、ハロゲンプラズマまたは水素プラズマを用いる、炭化珪素半導体の洗浄方法。 - 前記酸化膜(3)を除去する工程では、前記ハロゲンプラズマとしてフッ素プラズマを用いる、請求項1に記載の炭化珪素半導体の洗浄方法。
- 前記酸化膜(3)を除去する工程では、前記酸化膜(3)の除去を20℃以上400℃以下の温度で行なう、請求項1に記載の炭化珪素半導体の洗浄方法。
- 前記酸化膜(3)を除去する工程では、前記酸化膜(3)の除去を0.1Pa以上20Pa以下の圧力で行なう、請求項1に記載の炭化珪素半導体の洗浄方法。
- 前記酸化膜(3)を形成する工程では、酸素プラズマを用いる、請求項1に記載の炭化珪素半導体の洗浄方法。
- 前記酸化膜(3)を形成する工程と前記酸化膜(3)を除去する工程との間では、前記炭化珪素半導体(1)は大気から遮断された雰囲気内に配置される、請求項1に記載の炭化珪素半導体の洗浄方法。
- 炭化珪素半導体(1)の表面に酸化膜(3)を形成するための形成部(11)と、
ハロゲンプラズマまたは水素プラズマを用いて前記酸化膜を除去するための除去部(12)と、
前記炭化珪素半導体(1)を搬送することができるように前記形成部(11)と前記除去部(12)とを接続する接続部(13)とを備え、
前記接続部(13)における前記炭化珪素半導体(2)を搬送するための領域は、大気から遮断され得る、炭化珪素半導体の洗浄装置。 - 炭化珪素半導体(1)の表面に酸化膜(3)を形成するための形成部(11)と、
ハロゲンプラズマまたは水素プラズマを用いて前記酸化膜(3)を除去するための除去部(12)とを備え、
前記形成部(11)と前記除去部(12)とは同一である、炭化珪素半導体の洗浄装置。
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CN2011800042085A CN102687250A (zh) | 2010-06-16 | 2011-04-21 | 清洁碳化硅半导体的方法和用于清洁碳化硅半导体的装置 |
CA2773511A CA2773511A1 (en) | 2010-06-16 | 2011-04-21 | Method of cleaning silicon carbide semiconductor and apparatus for cleaning silicon carbide semiconductor |
US13/395,621 US20120178259A1 (en) | 2010-06-16 | 2011-04-21 | Method of cleaning silicon carbide semiconductor and apparatus for cleaning silicon carbide semiconductor |
KR1020127007289A KR20130076788A (ko) | 2010-06-16 | 2011-04-21 | 탄화규소 반도체의 세정 방법 및 탄화규소 반도체의 세정 장치 |
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GB201318463D0 (en) * | 2013-08-13 | 2013-12-04 | Medical Res Council | Graphene Modification |
CN103681246B (zh) * | 2013-12-30 | 2017-10-17 | 国家电网公司 | 一种SiC材料清洗方法 |
CN105710082B (zh) * | 2014-12-02 | 2018-03-06 | 中国科学院上海硅酸盐研究所 | 一种去除金属纳米线表面有机物及氧化层的方法 |
JP6415360B2 (ja) * | 2015-03-12 | 2018-10-31 | 昭和電工株式会社 | 炭化珪素単結晶基板の製造方法 |
FR3034252B1 (fr) * | 2015-03-24 | 2018-01-19 | Soitec | Procede de reduction de la contamination metallique sur la surface d'un substrat |
DE102015212099B4 (de) | 2015-06-29 | 2022-01-27 | Adidas Ag | Sohlen für Sportschuhe |
JP6458677B2 (ja) * | 2015-08-05 | 2019-01-30 | 三菱電機株式会社 | 炭化珪素エピタキシャルウエハの製造方法及び製造装置 |
TWI817756B (zh) | 2015-09-22 | 2023-10-01 | 美商應用材料股份有限公司 | 清洗方法 |
CN106024586B (zh) * | 2016-06-23 | 2018-07-06 | 扬州扬杰电子科技股份有限公司 | 一种碳化硅表面清洁方法 |
CN108257855B (zh) * | 2016-12-28 | 2021-09-10 | 全球能源互联网研究院 | 高k栅介质层的制备方法及碳化硅MOS功率器件 |
US10575588B2 (en) | 2017-03-27 | 2020-03-03 | Adidas Ag | Footwear midsole with warped lattice structure and method of making the same |
CN109524304B (zh) * | 2018-11-21 | 2021-04-27 | 北京国联万众半导体科技有限公司 | 碳化硅栅介质氟等离子体的处理方法及碳化硅功率器件 |
DE102019218727A1 (de) * | 2019-12-03 | 2021-06-10 | Robert Bosch Gmbh | Vorrichtung und verfahren zum bearbeiten mindestens eines halbleiter-substrates |
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US11786008B2 (en) | 2020-10-07 | 2023-10-17 | Adidas Ag | Footwear with 3-D printed midsole |
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US11589647B2 (en) | 2020-10-13 | 2023-02-28 | Adidas Ag | Footwear midsole with anisotropic mesh and methods of making the same |
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- 2011-04-21 CN CN2011800042085A patent/CN102687250A/zh active Pending
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- 2011-04-21 US US13/395,621 patent/US20120178259A1/en not_active Abandoned
- 2011-04-21 WO PCT/JP2011/059820 patent/WO2011158557A1/ja active Application Filing
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