LOW ELECTRON TEMPERATURE MICROWAVE SURFACE-WAVE PLASMA (SWP) PROCESSING METHOD AND APPARATUS

摘要

A surface wave plasma (SWP) source couples pulsed microwave (MW) energy into a processing chamber through, for example, a radial line slot antenna, to result in a low mean electron energy (T_e). To prevent impingement of the microwave energy onto the surface of a substrate when plasma density is low between pulses, an ICP source, such as a helical inductive source, a planar RF coil, or other inductively coupled source, is provided between the SWP source and the substrate to produce plasma that is opaque to microwave energy. The ICP source can also be pulsed in synchronism with the pulsing of the MW plasma in phase with the ramping up of the MW pulses. The ICP also adds an edge dense distribution of plasma to a generally chamber centric MW plasma to improve plasma uniformity.