Electrostatic control of deposition of, and etching by, ionized materials in semiconductor processing

摘要

Deposition of ionized material at a beveled or non-flat edge of a semiconductor wafer and the etching by the ionized material at such edge is controlled in a high density plasma processing machine by surrounding the wafer with a conducting ring to affect sheath potential and deflecting the ions of the material in such a way that the deposition and etching rate changes in a controlled way over the region immediately adjacent the wafer edge. The ring may be biased in several ways to control the ion flux to the wafer edge.