Method and apparatus for synthesizing diamond

Claim 1

A method of synthesizing diamond, which is substantially a method of synthesizing diamond by applying low-pressurized vapor phase, wherein said method uses carbon source such as solid carbon, or hydrocarbon, or hydrocarbon containing O and N in the bonded radical, or carbon tetrachloride, where said method causes raw-material compound gas composed of a mixture of said carbon ingredient and hydrogen to be activated for eventually precipitating diamond on the surface of substrate (4) being heated to a minimum of 600 ° C through a maximum of 1,200 ° C, wherein comprising steps and processes of: causing thermoelectron radiating material (2) heated to a minimum of 1,600 ° C to activate said compound gas; generating potential by connecting said thermoelectron radiating material (2) to negative electrode and grid (3) disposed between said thermoelectron radiating material (2) and substrate (4) subject to coating to positive electrode by applying a DC power-supply source; extracting thermoelectrons from said thermoelectron radiating material (2) for generating plasma; generating potential by connecting grid (3) to positive electrode and substrate (4) to negative electrode by applying another DC power-supply source (7) for generating plasma while maintaining potential of said substrate (4) negative; jointly applying effect of activation generated by thermoelectron radiating material (2) and another activation caused by generation of DC plasma; and controlling pressure inside of plasma-generating reactor to be a minimum of 10 Torr and a maximum of 400 Torr, respectively.

Claim 2

A method of synthesizing diamond, which is substantially a method of synthesizing diamond by applying low-pressurized vapor phase, wherein said method uses carbon source such as solid carbon, or hydrocarbon, or hydrocarbon containing O and N in the bonded radical, or carbon tetrachloride, where said method causes raw-material compound gas composed of a mixture of said carbon ingredient and hydrogen to be activated for eventually precipitating diamond on the surface of substrate (4) being heated to a minimum of 600 ° C through a maximum of 1,200 ° C, wherein comprising steps and processes of: causing thermoelectron radiating material (2) heated to a minimum of 1,600 ° C to activate said compound gas; generating potential by connecting said thermoelectron radiating material (2) to negative electrode and grid (3) disposed between said thermoelectron radiating material (2) and substrate (4) subject to coating to positive electrode by applying a DC power-supply source; extracting thermoelectrons from said thermoelectron radiating material (2) for generating plasma; generating potential by connecting grid (3) to positive electrode and substrate (4) to negative electrode by applying another DC power-supply source (7) for generating plasma while maintaining potential of said substrate (4) negative; jointly applying effect of activation generated by thermoelectron radiating material (2) and another activation caused by generation of DC plasma; and controlling pressure inside of plasma-generating reactor to be a minimum of 10 Torr and a maximum of 400 Torr, respectively.