# US 6,296,716 B1 · Process for cleaning ceramic articles > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,296,716 B1 - Document ID: US6296716B1 - Status: Granted - Kind: B1 - Application number: 09/470,510 - Filed: 1999-12-22 - Granted: 2001-10-02 - Earliest claimed: 1999-10-01 - Assignees: Saint-Gobain Ceramics & Plastics, Inc. - Inventors: Andrew G. Haerle; Gerald S. Meder - Web page: https://patentgrep.com/patent/US6296716B1 ## CPC - B24C 1/086: {Descaling; Removing coating films} - B24C 1/003: {using material which dissolves or changes phase after the treatment, e.g. ice, CO2} - B24C 3/322: {for electrical components} - C04B 41/009: {characterised by the material treated} - C04B 41/53: involving the removal of at least part of the materials of the treated article, {e.g. etching, drying of hardened concrete (C04B41/0036 - C04B41/0054 take precedence)} - C04B 41/91: involving the removal of part of the materials of the treated articles, e.g. etching - C23C 16/4407: {Cleaning of reactor or reactor parts by using wet or mechanical methods} - H10P 72/0406: {for cleaning followed by drying, rinsing, stripping, blasting or the like} - H10P 72/0421: {for drying etching} - Y10S 134/902: Semiconductor wafer - B24C: ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A method for cleaning ceramic workpieces such as SiC boats used in semiconductor fabrication is disclosed. The method comprises washing a virgin or used ceramic workpiece with a strong acid and then using a pelleted CO2 cleaning process on the acid-washed component. The inventive method has been found to produce a workpiece having a very low level of metallic and particulate contaminants on its surface. ## Claims ### Claim 1 A process for cleaning a semiconductor processing component having an inorganic surface, the process comprising the steps of: a) exposing the inorganic surface to a solvent having at least 1 v/o of an acid selected from the group consisting of HF, acids having a pKa of less than about one, and mixtures thereof, and b) directing a flow of frozen CO2 pellets upon the surface, wherein after steps a) and b) are performed the inorganic surface has a metallic contaminant concentration of at most about 600 ppm, as measured by SIMS at a depth of about 10 nm. ### Claim 2 (depends on 1) The process of claim 1, wherein the metallic contaminant concentration other than alkaline and alkaline earth metals is at most about 400 ppn, as measured by SIMS at a depth of about 10 nm. ### Claim 3 (depends on 1) The process of claim 1, wherein the metallic contaminant concentration of iron is at most about 225 ppm, as measured by SIMS at a depth of about 10 nm. ### Claim 4 (depends on 1) The process of claim 1, wherein after the flow of frozen CO2 pellets is directed onto the surface, the component is installed in a furnace used for processing semiconductor wafers. ### Claim 5 (depends on 1) The process of claim 1, wherein after the flow of frozen CO2 pellets is directed onto the surface, the component is sealed in a package suitable for storage and transport. ### Claim 6 (depends on 1) The process of claim 1, wherein prior to the step of exposing the inorganic surface to the solvent the component is subjecting to blasting with green SiC particles. ### Claim 7 (depends on 1) The process of claim 1, wherein the inorganic surface is selected from the group consisting of Si, diamond, Y2O3, ZrO2, SiC, Si3N4, AlN, Al2O3 and quartz. ### Claim 8 (depends on 1) The process of claim 1, wherein the inorganic surface has a vapor-deposited coating thereon. ### Claim 9 (depends on 1) The process of claim 1, wherein the surface is a vapor-deposited material selected from the group consisting of CVD Si, CVD SiO2, CVD SiC, CVD Si3N4, CVD diamond, Y2O3 and ZrO2. ### Claim 10 (depends on 1) The process of claim 1, wherein the inorganic surface comprises a coating provided by sputter deposition or spray coating. ### Claim 11 (depends on 4) The process of claim 4, wherein no additional cleaning steps are carried out between completing the flow of frozen CO2 pellets and installing the component in the furnace. ### Claim 12 (depends on 5) The process of claim 5, wherein no additional cleaning steps are carried out between completing the flow of frozen CO2 pellets and packaging the component. ### Claim 13 (depends on 5) A process as in claim 5 which includes the further steps of removing the component from the package and installing the component into a furnace used for processing semiconductor wafers. ### Claim 14 (depends on 13) A process as in claim 13 wherein no additional cleaning steps are carried out between removing the component from the package and installing it into the furnace. ### Claim 15 A process for cleaning a semiconductor processing component having an inorganic surface, the process comprising the steps of: a) subjecting the component to blasting with green SiC particles; b) exposing the inorganic surface to a solvent having at least 1 v/o of an acid selected from the group consisting of HF, acids having a pKa of less than about one, and mixtures thereof; and c) predicting a flow of frozen CO2 pellets upon the surface.