Isolation substrate ring for plasma reactor

Abstract

A radio frequency (RF) glow discharge plasma etch electrode design is disclosed which is capable of creating high power density plasma with uniform etch rates, while providing access for automatic loading semiconductor wafers from outside of the plasma region. The electrode assembly comprises of an electrode to which RF energy is applied surrounded by an insulator, which in turn surrounded a grounded surface all of which have cylindrical symmetry. When placed a small distance from a flat, grounded substrate, the electrode assembly creates a volume which can effectively combine a high power density plasma, while maintaining a sufficient channel for pumping a gas flow and for observing the plasma optically. The same channel is widened for automatic transport of semiconductor wafers from outside of the plasma reactor chamber. Such confined high power density plasma are important for high rate, uniform, anisotropic etching, especially for silicon dioxide.