Preferred orientations in the Ge/SiO₂ interface

The study of preferred orientations in the Ge/SiO₂ interface was measured by observing the development and re-orientation of single crystal Ge spheres on amorphous SiO₂ substrates. The annealing temperatures ranged from 53 to 98 per cent of the melting temperature of Ge. At low annealing temperatures the Ge orientation distribution revealed three cusps in the interfacial energy versus misorientation curve corresponding to (111), (220) and (311) planes. For higher annealing temperatures one additional cusp in the interfacial energy versus misorientation curve for (400) planes is observed. The results are discussed in terms of interfacial entropy, atomic packing and electronic effects.