Factors to control uniformity of single crystal diamond growth by using microwave plasma CVD

摘要

Uniformity of the growth rate of single crystal diamond by microwave plasma chemical vapor deposition is studied experimentally and theoretically. We show growth condition to improve uniformity of the growth rate experimentally, in which moderate gas pressure and elevated MW power are shown to be necessary. Conventional theories are compared with the experimentally obtained growth rates, which well explain the absolute values of the growth rate in the central regions but fails to describe its spatial distribution. Possible revised formula to explain the experimentally obtained (non-)uniformity based on the micro- and macroscopic simulations is proposed, which indicates importance to control the uniformity of the substrate temperature.