Patent ID: 7662441

Claim:
A method for manufacturing a diamond film comprising: forming a plasma of finite volume near a substrate by subjecting a gas containing at least hydrogen and carbon in a vacuum chamber to periodic pulsed discharges using a pulsed microwave plasma by applying only a repeated succession of a low-power state and a high-power state, in which the ratio of the duration of the high-power state to the duration of the low-power state is between 1/9 and 1, and having a peak absorbed power P C so as to obtain at least carbon-containing radicals in the plasma, and depositing the said carbon-containing radicals on the substrate in order to form a diamond film thereon; wherein the power being injected into the volume of the plasma with a peak power density of at least 100 W/cm 3 while maintaining the substrate to a substrate temperature of between 700° C. and 1000° C. and also wherein the pressure of the plasma is maintained between 100 mbar and 350 mbar.