Vapor-Phase Polishing of Silicon with H2-HBr Gas Mixtures

The production of smooth, flat, and clean surfaces on semiconductors, such as silicon and germanium, for the fabrication of planar devices is generally achieved by a combination of mechanical and chemical polishing procedures. With suitable equipment and fine polishing grit a skilled operator can mechanically polish a silicon single-crystal disk to optical flatness. Such treatment leaves a mechanically-damaged surface layer on the polished sample that is removed by a chemical etching procedure which removes more silicon while retaining the smooth, flat surface.