# US 5,702,586 A · Polishing diamond surface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,702,586 A - Document ID: US5702586A - Status: Granted - Kind: A - Application number: 08/266,770 - Filed: 1994-06-28 - Granted: 1997-12-30 - Earliest claimed: 1994-06-28 - Assignees: The United States of America as represented by the Secretary of the Navy - Inventors: Pehr E. Pehrsson; Michael L. Marchywka - Web page: https://patentgrep.com/patent/US5702586A ## CPC - C25F 3/02: Etching - C25F: PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR ## Abstract Process of smoothing or polishing a diamond surface to reduce asperities reon to a level as low as about 20 nm from the horizontal by implanting the diamond surface with ions to form a non-diamond carbon damage layer on or below the diamond surface below the disparity depth and dissolving the non-diamond carbon by submerging the non-diamond carbon in a liquid having sufficient electric field to dissolve the non-diamond carbon. ## Claims ### Claim 1 A process for smoothing a diamond surface containing asperities thereon comprising the steps of: (a) implanting ions in the diamond surface to form non-diamond carbon on the diamond surface and the asperities by directing an ion beam at an angle of less than 90.degree. from the diamond surface, and (b) removing the non-diamond carbon by electrochemical etching. ### Claim 2 (depends on 1) The process of claim 1 wherein the thickness of the non-diamond carbon layer is below the depth of asperities. ### Claim 3 (depends on 2) The process of claim 2 wherein the step of implanting ions is accomplished with ion beam at an energy level of about 1.times.10.sup.4 to about 1.times.10.sup.7 electron volts. ### Claim 4 (depends on 3) The process of claim 3 wherein the diamond surface is curved and wherein the step of implanting ions is accomplished with ions selected from the group consisting of carbon ions, argon ions and mixtures thereof. ### Claim 5 (depends on 4) A product made by the process of claim 4. ### Claim 6 (depends on 1) The process of claim 1 wherein said step of removing is carried out by submerging the non-diamond carbon in a liquid under an electric field of sufficient strength to electrochemically etch the non-diamond carbon. ### Claim 7 (depends on 6) The process of claim 6 wherein the thickness of the non-diamond carbon layer is below depth of asperities; and wherein the step of implanting ions is accomplished with ion beam at an energy level of about 1.times.10.sup.4 to about 1.times.10.sup.7 electron volts. ### Claim 8 (depends on 7) The process of claim 7 wherein the liquid has a resistivity of of about 100 ohm-centimeters to about 10 megaohm-centimeters and the electric field in the liquid is about 1-200 v/cm. ### Claim 9 (depends on 8) The process of claim 8 wherein the electric field in the liquid is about 10-100 v/cm and wherein the liquid is selected from the group consisting of water, acid, ammonium hydroxide, aqueous surfactant solutions and mixtures thereof. ### Claim 10 (depends on 9) The process of claim 9 including the step of turning the diamond surface in reference to the implanting ions to form non-diamond carbon around the asperities. ### Claim 11 (depends on 10) The process of claim 10 wherein the liquid is selected from the group consisting of water and aqueous solutions of an acid and wherein the step of implanting ions is accomplished with ions selected from the group consisting of carbon ions, argon ions and mixtures thereof. ### Claim 12 (depends on 11) A product made by the process of claim 11 having a curved surface, the diamond surface being smooth to within at least about 20 nm surface variation. ### Claim 13 (depends on 9) A product made by the process of claim 9. ### Claim 14 A process for polishing a diamond containing asperities thereon comprising the steps of: (a) forming non-diamond carbon on the diamond and the asperities by directing an ion beam having an energy of about 1.times.10.sup.4 to about 1.times.10.sup.7 electron volts at the diamond at an angle of less than 90.degree. with respect to the diamond; (b) dissolving the non-diamond carbon disposed on the diamond and the asperities by submerging the non-diamond carbon in a liquid having an electric field of sufficient strength to remove the non-diamond carbon; and (c) turning the diamond to form non-diamond carbon around the asperities. ### Claim 15 (depends on 14) The process of claim 14 wherein the liquid has a resistivity of about 100 ohm-centimeters to about 10 megaohm-centimeters; wherein the electric field in the liquid is about 1-200 v/cm; and wherein the liquid is selected from the group consisting of water, acids, ammonium hydroxide, aqueous surfactant solutions and mixtures thereof. ### Claim 16 (depends on 15) The process of claim 15 wherein the liquid is selected from the group consisting of water and aqueous solutions of an acid; wherein the step of forming the non-diamond carbon is accomplished by directing an ion beam selected from the group consisting of carbon ions, argon ions and mixtures thereof at the diamond; and wherein the diamond has at least one non-planar surface having asperities thereon with the ion beam being directed at the asperity. ### Claim 17 (depends on 16) A product of the process of claim 16. ### Claim 18 (depends on 14) A product of the process of claim 14.