Input power dependence of growth rate and quality of diamond films deposited in a d.c. arcjet system

Abstract

Abstract Using a d.c. arcjet chemical vapor deposition (CVD) system, the dependence of growth rate and quality of diamond films on input power to the plasma torch was investigated. It was found that in a remote methane feed mode, the growth rate of diamond films increases as the input power increases, confirming the benefit of using high power torches. But unexpectedly, the content of non-diamond carbon or defect density in thin diamond films was found to increase as a function of input power, and a thick diamond film deposited at a low input power was of high quality. These results were analyzed considering the kinetics of gas activation taking place in the CVD process. It is believed that high input power along with a high density of atomic hydrogen will effectively activate hydrocarbon radicals, which will bring about both a high growth rate of diamond films and a large probability of defect incorporation into the growing materials.