Patent ID: 6248400
Filing Date: 2001-06-19
Classification: C23C,H04R

Abstract:
A method for producing a shaped diamond film which comprises:preparing a shaped substrate having a surface portion thereof composed of a material, which does not react with carbon and which has a different thermal expansion coefficient than the diamond film, said material being a ceramic material or a metal selected from the group consisting of copper, platinum, gold and alloys thereof;depositing a diamond film onto the shaped substrate from a mixed gas, which contains hydrogen, a carbon-containing gas and an inert gas, by a DC plasma jet CVD process so as to deposit said diamond film at a rate of at least 30 .mu.m per 30 minutes; said mixed gas being at a constant pressure and said hydrogen, carbon-containing and inert gases being provided at a constant flow rate;recycling the mixed gas, the composition of which is maintained constant by the addition of hydrogen, the carbon-containing gas and the inert gas; wherein the flow rate of the recycled mixed gas in proximity to the anodic point of the plasma torch is at least 5 m/s;cooling the shaped substrate, whereby the diamond film deposited on the shaped substrate separates from the shaped substrate; andremoving the shaped diamond film from the shaped substrate.