Process for preferentially etching polycrystalline silicon.

摘要

This disclosure relates to a process for etching polycrystalline silicon (14) in preference to single crystal silicon (10). Polycrystalline silicon (14) is anisotropically etched in a plasma which includes a noncarbonaceus silicon etching compound such as chlorine together with about 0.4 - 1.5 percent by volume of oxygen. The process is used to fabricate semiconductor devices which require the etching of polycrystalline silicon (14) in the presence of exposed monocrystalline silicon (10).