Method for growing a diamond thin film on a substrate by plasma enhanced chemical vapor deposition

A method is provided for growing a diamond thin film on a selected substrate. First the substrate is prepared by scratching the surface thereof with diamond paste. The substrate is then confined in an enclosed space which includes high purity hydrogen and high purity methane gasses under relatively low pressure. The substrate is then irradiated with microwave energy to subject the substrate to a plasma exhibiting a first predetermined power density for a first period of time sufficient to form, on the substrate, diamond-like ball structure particles. The power density of the plasma to which the substrate is exposed is then effectively increased to a second predetermined power density and the substrate in exposed to the plasma for a second period of time sufficiently long such that (100) diamond faces grow on top of the ball structure particles. Finally, the irradiation of the substrate with the diamond-like ball structure particles thereon is continued at the second predetermined powe