Oriented growth of semiconductors I. Orientations in gallium arsenide grown epitaxially on germanium

Abstract
The orientations in gallium arsenide grown epitaxially on germanium by hydrogen chloride transport have been studied using glancing angle electron diffraction. Development of twin orientations depends upon the temperature during deposition and markedly upon the orientation of the substrate. Decrease of deposition temperature favours the formation of twin orientations, some of which arise by successive twinning about more than one 〈111〉 axis. Still lower deposition temperatures give rise to fibre textures and sometimes to the wurtzite phase of GaAs. The deposition temperatures required for elimination of twinning increase with substrate orientation in the order (001)< (110)< (111); this behaviour is shown to be consistent with the requirement of a (111) facet for initiation of a twin orientation at a coherent twin boundary.