Numerical Investigation on Uniform Plasma Production in Planar Type Surface Wave Plasma Processing Device
Abstract
Microwave power propagation and absorption in the planar type surface wave plasma device (developed by Sumitomo Metal Co.) has been numerically investigated. It has a four layer structure consisting of an upper dielectric slow wave structure, an air gap, a dielectric window and a plasma chamber. The finite difference time domain (FDTD) method has been used for 2 dimensional configurations where the plasma is assumed to be a cold electron plasma with a density gradient at the plasma surface. It has been found that the microwave that propagates along the upper slow wave structure induces a large amplitude standing wave that effectively excites the plasma surface wave. This wave has been numerically demonstrated to have a resonance at the same electron density as that predicted by the theory. It is also found that the placement of a slitted metal cover plate on the dielectric window gives a more uniform power absorption at the plasma surface. Proper arrangement of slits in the metal cover plate will contribute to improve the uniformity of the plasma produced in future SWP processing devices with large bores.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- November 1998
- Bibcode:
- 1998APS..DPP.J5P17M