| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing diamond by which diamond of α≤1 can be synthesized at a high efficiency by using an oxygen-containing gas such as carbon dioxide, and to provide a diamond product. <P>SOLUTION: Diamond is subjected to vapor phase synthesis under conditions shown in the following numerical inequality provided that the numerical ratio occupied by hydrogen atoms in a reaction gas is defined as 2x(%), the numerical ratio of carbon atoms as y(%), the numerical ratio of oxygen atoms as z(%), and a substrate temperature as T(°C): T>33500×(y-z)/(x+y-z)+717T<254000×(y-z)/(x+y-z)+717T<1100. The reaction gas comprises hydrogen, methane and carbon dioxide. The reaction gas is made into a plasma state by microwaves of ≥5 kW to produce the diamond by the vapor phase synthesis. <P>COPYRIGHT: (C)2004,JPO |
