Using ionic-plasma etching for treatment and study of surface layers of crystals

High-frequency (16, 40 MHz) ionic-plasma etching of monocrystals of a number of materials, particularly chromium, has been carried out. Correlation between the ionic-plasma etching rate and machinability determined by forces of interatomic interaction is established. It is shown that sensitivity to various structural non-homogeneities permits to use ionic-plasma etching during investigations of the processes of formation and propagation of various defects, for example cracks. The method is noted to have promise in semiconductor device fabrication