# US 8,770,827 B2 · Method for coating micromechanical parts with high tribological performances for application in mechanical systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,770,827 B2 - Document ID: US8770827B2 - Status: Granted - Kind: B2 - Application number: 13/319,446 - Filed: 2010-05-18 - Published: 2012-03-01 - Granted: 2014-07-08 - Earliest claimed: 2009-05-18 - Assignees: The Swatch Group Research and Development Ltd - Applicants: Detlef Steinmuller; Doris Steinmuller; Herwig Drexel; Slimane Ghodbane; David Richard; Pierre Cusin - Inventors: Detlef Steinmuller; Doris Steinmuller; Herwig Drexel; Slimane Ghodbane; David Richard; Pierre Cusin - Web page: https://patentgrep.com/patent/US8770827B2 ## CPC - C23C 16/279: {control of diamond crystallography} - C23C 16/26: Deposition of carbon only - C23C 16/271: {using hot filaments} - G04B 13/02: Wheels; Pinions; Spindles; Pivots (bearings G04B31/00 {; chain wheels, spindles for chain wheels, also chains and driving weights G04B1/08}) - G04B 15/14: Component parts or constructional details, e.g. construction of the lever or the escape wheel {(assembly and manufacture of the spring G04B1/145; assembly and manufacture of components, e.g. pinions, spindles G04B13/02; lubrication of clockwork bearings G04B31/008; oils for clockwork bearings in general G04B31/08)} - G04D 3/0069: {for working with non-mechanical means, e.g. chemical, electrochemical, metallising, vapourising; with electron beams, laser beams} - 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) - G04B: MECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS (spring- or weight-driven mechanisms in general F03G; electromechanical clocks or watches G04C; electromechanical clocks with attached or built-in means operating any device at pre-selected times or after predetermined time intervals G04C23/00; clocks or watches with stop devices G04F7/08) - G04D: APPARATUS OR TOOLS SPECIALLY DESIGNED FOR MAKING OR MAINTAINING CLOCKS OR WATCHES ## Abstract Method for coating micromechanical components of a micromechanical system, in particular a watch movement, comprising: providing a substrate component to be coated; providing said component with a diamond coating; wherein diamond coating is provide by CVD in a reaction chamber and during CVD deposition, during the last portion of the growth process, a controlled change of the carbon content within the reaction chamber is provided, thereby providing a change of the sp2/sp3 carbon bonds in the vicinity of the surface. Corresponding micromechanical components are also provided. ## Claims ### Claim 1 A method for coating micromechanical components of a micromechanical system, including a watch movement, comprising: providing a substrate component to be coated; and providing said substrate component with a diamond coating, on a surface of said substrate component, of a given final thickness; wherein said diamond coating is provided by CVD deposition in a reaction chamber; wherein in a first phase of the CVD deposition process only sp3 hybridised carbon is deposited on said substrate over a first thickness; wherein during a second phase of CVD deposition process, a controlled change of the carbon content within the reaction chamber is provided, thereby providing a change of the sp2/sp3 carbon bonds in a vicinity of the surface over a second thickness thereby forming an outer layer having a top, exterior surface; and wherein the change of sp2/sp3 carbon bond is such that there is a gradual increase of sp2 hybridised carbon content towards the top, exterior surface. ### Claim 2 (depends on 1) The method for coating micromechanical components of a micromechanical system according to claim 1, wherein the second thickness is of the order of one micrometer. ### Claim 3 (depends on 1) The method for coating micromechanical components of a micromechanical system according to claim 1, wherein said change is an increase of the carbon content within the reaction chamber. ### Claim 4 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, wherein said increase of carbon content is obtained by increasing the proportion of carbon containing reactant gas. ### Claim 5 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, wherein said increase of carbon content is obtained by adding an additional carbon containing gas. ### Claim 6 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3 further comprising increasing the temperature and/or pressure within the processing reaction chamber so as to increase said carbon content. ### Claim 7 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, further comprising adding gaseous nitrogen to the reaction chamber to increase said carbon content. ### Claim 8 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, further comprising replacing hydrogen by argon to increase said carbon content. ### Claim 9 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, further comprising adding at least one rare gas to increase said carbon content. ### Claim 10 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, further comprising causing lattice distortion to increase said carbon content. ### Claim 11 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, further comprising post-treatment consisting in adding metal containing compounds on top of the diamond in order to decrease the sticking properties. ### Claim 12 (depends on 3) The method for coating micromechanical components of a micromechanical system according to claim 3, further comprising post-treatment consisting in termination of the diamond-surface, wherein said termination is provided using an element selected from the list consisting of hydrogen, halogens, metals, electrical conductive minerals/organic molecules or proteins. ### Claim 13 (depends on 3) The micromechanical component for a micromechanical system, in particular a watch movement, wherein said component is obtained with a method according to claim 3. ### Claim 14 A micromechanical component for a micromechanical system, including a watch movement, said component defining a substrate for an external surface layer made of diamond, wherein said diamond surface layer comprises a first portion in contact with the substrate of a first thickness, said first portion being constituted of sp3 hybridised carbon and a second portion remote from the substrate of a second thickness said second portion being constituted of a mix of sp2 and sp3 hybridised carbon, said second portion forming an outer layer having a top, exterior surface, the sp2 hybridised carbon content gradually increasing towards the top, exterior surface. ### Claim 15 (depends on 14) The micromechanical component for a micromechanical system according to claim 14 wherein said second portion comprises a gradual increase of sp2 hybridised carbon content. ### Claim 16 (depends on 14) The micromechanical component for a micromechanical system according to claim 14 wherein the second thickness is of the order of one micrometer.