PURPOSE: To accelerate the speed of chemical vapour deposition(CVD) by bringing a substrate into contact with a gas phase of a prescribed energy content, and bringing the substrate into contact with a gas phase of an energy content being changed timely later thereby forming fine diamond crystal on the surface of the substrate.
CONSTITUTION: A monocrystalline Si disk substrate is installed on a substrate holder inside a reactor, H2 gases mixed with carbon-containing gases such as methane gases in ≤30% are supplied and after the pressure in the reactor is regulated to 10-5 to 1 bar, preferably, to about 50 millibars, the substrate is heated to 450 to 1200°C. Next, microwave energy at the frequency of about 2.45 GHz is supplied into the reactor, and pulsed plasma is maintained. The microwave energy to be supplied is varied by providing microwave power within the range of 400 to 1300 W at the frequency of about 10 Hz in time, the microwave power is regulated to the fixed value of about 1000 W after the lapse of about 30 minutes, this is maintained for about 900 minutes, and the tightly deposited polycrystalline diamond layer of a prescribed thickness is obtained on the substrate.
HANSU RIDOCHIN
ARUNDO RITSUTSU
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