US 20130129983A1 (19) United States (12) Patent Application Publication (10) Pub. N0.2 US 2013/0129983 A1 Kley (43) Pub. Date: May 23, 2013

(54) SILICON CARBIDE STABILIZING OF SOLID Publication Classi?cation DIAMOND AND STABILIZED MOLDED AND FORMED DIAMOND STRUCTURES (51) Int. Cl. C23C16/32 (2006.01) (75) Inventor: Victor B. Kley, Berkeley, CA (US) (52) us. c1. CPC ...... C23C16/325(2013.01) (73) Assignee: Metadigm LLC, Berkeley, CA (US) USPC ...... 428/164; 428/161; 427/249.16; 428/408 (21) App1.No.: 13/474,637 (57) ABSTRACT A technique alloWs diamonds, Whether synthetic or naturally (22) Filed: May 17, 2012 occurring, and regardless of shape, to resist high temperatures in an oxidizing environment. This is accomplished by coating Related US. Application Data the diamond With silicon carbide (SiC). The resulting product may be referred to as SiC-stabilized diamond. A further ben (63) Continuation of application No. 11/949,742, ?led on e?t With respect to diamond jewelry is that by applying SiC to Dec. 3, 2007, Continuation of application No. 1 1/079, the diamond jeWel, a unique pattern is made by small varia 019, ?led on Mar. 11, 2005, noW abandoned. tions in the ?lm thickness. These variations appear under UV (60) Provisional application No. 60/554,194, ?led on Mar. and X-ray examination, and along With a unique and invariant 16, 2004. Weight, provide a unique signature to the jeWel.

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SILICON CARBIDE STABILIZING OF SOLID [0008] It is noted that for those embodiments Where the DIAMOND AND STABILIZED MOLDED AND diamond is formed on a sacri?cial substrate (e. g., a sphere on FORMED DIAMOND STRUCTURES Which a diamond shell is groWn), Which substrate is later Wholly or partially removed, the protective layer can also be CROSS-REFERENCES TO RELATED Wholly or partially removed. APPLICATIONS [0009] Further improvements, resistance to oxygen pen [0001] This application is a continuation of US. patent etration of the SiC layer along With speci?c optical and iden application Ser. No. 11,949,742, ?led Dec. 3, 2007, entitled ti?cation functions by any or all of silicon carbide, silicon, “Silicon Carbide Stabilizing of Solid Diamond and Stabilized silicon ?uoride, magnesium ?uoride, silicon , tita Molded and Formed Diamond Structures,” Which is a con nium, titanium dioxide, carbide, , tantalum, tinuation of US. patent application Ser. No. 11/079,019 ?led tantalum carbide, , molybdenum, molybde Mar. 11, 2005, entitled “Silicon Carbide Stabilizing of Solid num carbide, molybdenum nitride, tungsten, tungsten car Diamond and Stabilized Molded and Formed Diamond bide, , boron carbide, , chro Structures,” Which claims the bene?t of US. Provisional mium, carbide, chromium nitride, chromium Application No. 60/554,194 ?led Mar. 16, 2004, entitled oxide, aluminum oxide. By suitably varying the materials and “Silicon Carbide Stabilizing of Solid Diamond and Stabilized thickness of successive layers We can construct an optically Molded and Formed Diamond Structures,” Which disclosure speci?c coating that can substantially identify any given (including the document attached thereto and characterized transparent coated structure like a diamond jeWel With a as “Novel Low-Temperature CVD Process for Silicon Car unique signature by scattered light or by coherent light or both bide MEMS, C. R. Stoldt, C. Carraro, W. R. Ashurst, M. C. and/or mass. Fritz, D. Gao, and R. Maboudian, Department of Chemical [0010] A further understanding of the nature and advan Engineering, University of California, Berkeley, Calif. 94720 tages of the present invention may be realized by reference to U.S.A.”) is incorporated herein by reference for all purposes. the remaining portions of the speci?cation and the draWings.

BACKGROUND AND SUMMARY OF THE BRIEF DESCRIPTION OF THE DRAWING INVENTION [0002] The following US. patents are incorporated by ref [0011] The draWing shoWs a speci?c embodiment of sili con carbide seeding on a diamond by a light coat of silicon (10 erence: US. Pat. Nos. 6,144,028, 6,252,226, 6,337,479, to 15 nm) folloWed by a silicon carbide or quick carbon 6,339,217. plasma. [0003] The present invention relates generally to diamonds, and more speci?cally to techniques for increasing the longev ity of diamonds. Yes, it’s true, diamonds are not forever. DESCRIPTION OF SPECIFIC EMBODIMENTS [0004] Diamonds, Whether synthetic or naturally occur ring, and regardless of shape, suffer from the inability to resist [0012] The draWing shoWs a speci?c embodiment of sili high temperatures in an oxidizing environment. They burn con carbide (SiC) seeding on a diamond by a light coat of like What they are, very expensive charcoal. In fact diamonds silicon (10 to 15 nm) folloWed by a silicon carbide or quick exposed to air at room temperature lose a small but measur carbon plasma. The ?rst silicon coat forms carbides With the able amount of carbon over time. diamond; the second groWs SiC. In the preferred embodiment a diamond such as jeWel 100 is implanted With a seed layer of [0005] The present invention eliminates this problem, and silicon, forming silicon carbide sites 102. A silicon carbide thus improves the longevity and value of diamond articles coating is then applied by CVD groWth of the silicon carbide. such as natural and synthetic diamond jeWelry, certain dia mond industrial applications, and the emerging area of dia [0013] The technique is Well knoWn in the art, and can mond as a structural material in building useful devices and folloW the teachings of the reference Novel Low-Temperature machines. In short, this is accomplished by coating the dia CVD Process for Silicon Carbide MEMS, C. R. Stoldt, C. mond With silicon carbide (SiC). The resulting product may Carraro, W. R. Ashurst, M. C. Fritz, D. Gao, and R. Mabou be referred to as SiC-stabilized diamond. dian, Department of Chemical Engineering, University of [0006] A further bene?t With respect to diamond jeWelry is California, Berkeley, Calif. 94720 U.S.A., Which uses 1,3 that by applying SiC to the diamond jeWel, a unique pattern is disilabutane, including such latter coating at loW tempera made by small variations in the ?lm thickness. These varia tures as described. Alternatively, a plasma arc is made With tions appear under UV and X-ray examination, and along silicon carbide and alloWed to condense on the seeded sur With a unique and invariant Weight, provide a unique signa face. ture to the jeWel. [0014] Thus it can be seen that various embodiments pro [0007] In another aspect of the invention, the SiC coating vide methods and articles of manufacture that may include the (Which may be doped to be conductive or left in its intrinsic coating of CVD, PECVD, synthetic solid, or natural solid form as an insulator) may be achieved by direct coating of diamond With any or all of silicon carbide, silicon, silicon diamond, or by the use of a thin layer of silicon to act as an ?uoride, magnesium ?uoride, , titanium, tita adhesion layer betWeen the diamond and SiC, or by use of a nium dioxide, carbide, titanium nitride, tantalum, tantalum thicker layer of silicon or other material to permit thicker carbide, tantalum nitride, molybdenum, molybdenum car structures of SiC and diamond to be bonded together. This bide, molybdenum nitride, tungsten, tungsten carbide, tung coating is useful in storing or handling and protecting dia sten nitride, boron carbide, boron nitride, chromium, chro mond shapes such as spheres used for ball bearings and the mium carbide, chromium nitride, chromium oxide, like. aluminum oxide. US 2013/0129983 A1 May 23, 2013

[0015] While the above is a complete description of speci?c tantalum, tantalum carbide, tantalum nitride, molybdenum, embodiments of the invention, the above description should molybdenum carbide, molybdenum nitride, tungsten, tung not be taken as limiting the scope of the invention as de?ned sten carbide, tungsten nitride, boron carbide, boron nitride, by the claims. chromium, chromium carbide, chromium nitride, chromium What is claimed is: oxide, aluminum oxide are used for any reason. 1. A method of treating a diamond comprising depositing a 15. The article of claim 12, and further comprising a silicon layer of silicon carbide on the diamond. layer interposed betWeen at least a portion of said silicon 2. The method of claim 1 Wherein any or all of silicon carbide layer and said surface of said diamond shape. carbide, silicon, silicon ?uoride, magnesium ?uoride, silicon nitride, titanium, titanium dioxide, carbide, titanium nitride, 16. The method of claim 15 Wherein any or all of silicon tantalum, tantalum carbide, tantalum nitride, molybdenum, carbide, silicon, silicon ?uoride, magnesium ?uoride, silicon molybdenum carbide, molybdenum nitride, tungsten, tung nitride, titanium, titanium dioxide, carbide, titanium nitride, sten carbide, tungsten nitride, boron carbide, boron nitride, tantalum, tantalum carbide, tantalum nitride, molybdenum, chromium, chromium carbide, chromium nitride, chromium molybdenum carbide, molybdenum nitride, tungsten, tung oxide, aluminum oxide are used for any reason. sten carbide, tungsten nitride, boron carbide, boron nitride, 3. The method of claim 1 Wherein the layer or layers vary chromium, chromium carbide, chromium nitride, chromium in thickness between 10 nm and 100 microns. oxide, aluminum oxide are used for any reason. 4. The method of claim 1, and further comprising deposit 17. The method of claim 15 Wherein any or all of silicon ing a layer of silicon, on Which the silicon carbide layer is carbide, silicon, silicon ?uoride, magnesium ?uoride, silicon deposited. nitride, titanium, titanium dioxide, carbide, titanium nitride, 5. The method of claim 4 Wherein any or all of silicon tantalum, tantalum carbide, tantalum nitride, molybdenum, carbide, silicon, silicon ?uoride, magnesium ?uoride, silicon molybdenum carbide, molybdenum nitride, tungsten, tung nitride, titanium, titanium dioxide, carbide, titanium nitride, sten carbide, tungsten nitride, boron carbide, boron nitride, tantalum, tantalum carbide, tantalum nitride, molybdenum, chromium, chromium carbide, chromium nitride, chromium molybdenum carbide, molybdenum nitride, tungsten, tung oxide, aluminum oxide are used for any reason. sten carbide, tungsten nitride, boron carbide, boron nitride, 18. The article of claim 15 Wherein the layer or layers vary chromium, chromium carbide, chromium nitride, chromium in thickness between 10 nm and 100 microns. oxide, aluminum oxide are used for any reason. 6. The method of claim 4 Wherein the layer or layers vary 19. The article of claim 15 in Which a unique combination in thickness between 10 nm and 100 microns. of layers, thickness variations and mass provide a signature 7. The method of claim 1 Wherein the diamond is one of a Which can not be duplicated and may be recorded and used to CVD groWn diamond, a PECVD groWn diamond, a synthetic identify the object. solid diamond, or a natural solid diamond. 20. A method that includes the coating of CVD, PECVD, 8. The method of claim 1 Wherein the silicon carbide layer synthetic solid, or natural solid diamond With any or all of is on the order of 1 micron in thickness. silicon carbide, silicon, silicon ?uoride, magnesium ?uoride, 9. The method of claim 1 Wherein the silicon carbide layer silicon nitride, titanium, titanium dioxide, carbide, titanium is between 10 nanometers and 200 nanometers in thickness. nitride, tantalum, tantalum carbide, tantalum nitride, molyb 10. The method of claim 1 Wherein the silicon carbide layer denum, molybdenum carbide, molybdenum nitride, tungsten, is doped to have a desired conductivity. tungsten carbide, tungsten nitride, boron carbide, boron 11. The method of claim 1 in Which a unique combination nitride, chromium, chromium carbide, chromium nitride, of layers, thickness variations and mass provide a signature chromium oxide, aluminum oxide. Which can not be duplicated and may be recorded and used to identify the object. 21. An article of manufacture that includes the coating of 12. An article of manufacture comprising: CVD, PECVD, synthetic solid, or natural solid diamond With a diamond shape having a surface; and any or all of silicon carbide, silicon, silicon ?uoride, magne a silicon carbide layer conforming to at least a portion of sium ?uoride, silicon nitride, titanium, titanium dioxide, car said surface of said diamond shape. bide, titanium nitride, tantalum, tantalum carbide, tantalum 13. The article of claim 12 Wherein the layer or layers vary nitride, molybdenum, molybdenum carbide, molybdenum in thickness between 10 nm and 100 microns. nitride, tungsten, tungsten carbide, tungsten nitride, boron 14. The method of claim 12 Wherein any or all of silicon carbide, boron nitride, chromium, chromium carbide, chro carbide, silicon, silicon ?uoride, magnesium ?uoride, silicon mium nitride, chromium oxide, aluminum oxide. nitride, titanium, titanium dioxide, carbide, titanium nitride, * * * * *