Chemical etching and cleaning procedures for Si, Ge, and some III-V compound semiconductors

Chemical etching and cleaning procedures that produce the most abrupt dielectric discontinuities between bulk and ambient (cleanest and/or smoothest surfaces) are determined by ellipsometry for single crystals of Si, Ge, and some III-V compounds. Differences among high-symmetry orientations for Si and Ge indicate that preferential etching may be a factor in minimizing the amount of interface material left at a surface.