Etch Pits on Dendritic Germanium. A Clarification

Abstract

Previous reports by Billig and Holmes of the orientations of etch pits on the main faces of germanium dendrites are not at first sight consistent with those recently reported by Bennett and Longini. It is shown that this discrepancy arose because the orientation of equilateral pits on {111} surfaces depends on the etchant used. A check on the earlier work confirms that there is in fact no contradiction: ferricyanide and WAg etches produce pits which point upwards on "perfect" faces grown in a "$G$ direction," while superoxol and similar etchants give pits pointing downwards.