The effect of oxygen in diamond deposition by microwave plasma enhanced chemical vapor deposition

Abstract

High quality diamond thin films were deposited on different substrates at temperatures from 300 to 1000 °C by the microwave plasma enhanced chemical vapor deposition (MPCVD) system. The quality of deposited diamond films was improved by adding oxygen in the gas mixtures. Different ratios of methane to oxygen concentration in hydrogen at different temperatures have been studied. At high temperatures (800–1000 °C), the addition of oxygen will not only enhance the growth rate of deposited films but also extend the region of diamond formation. At low temperatures (900 °C) were either graphitic or diamond containing a large amount of graphitic or amorphous carbon and at low temperatures (