Computational modeling of moderate pressure microwave plasma-assisted chemical vapor deposition reactors

Microwave plasma-assisted chemical vapor deposition (PACVD) reactors have been used extensively for the growth of diamond films. The design geometric features of these reactors vary to enable control and shaping of the electromagnetic fields and plasma discharge. In particular, the design and tuning of various geometric parameters is known to affect not only the electromagnetic field structure, but also the plasma shape during operation. For example, the positioning of the substrate height is known to greatly affect the plasma characteristics when changed as little as a few millimeters. In the past, empirical experience has often guided decisions for changing these physical parameters during design and operation. A more detailed numerical study of these effects related to the geometry and the interaction of the microwave fields and plasma discharge is required. This study may also lead to more efficient reactor designs and ultimately faster deposition rates.