Precipitation of supersaturated chromium solutions in gallium arsenide

Transmission electron microscopy has been used to investigate precipitation processes in gallium arsenide doped with chromium and Cr 2 O 3 . Whatever the doping technique, at concentrations of chromium 4 × 10 16 cm −3 the solid solution was observed to contain precipitates which grew, at least partially, due to the migration of substitutional atoms and their transformation into the precipitates. The process is accompanied by generation of vacancies from dislocation loops.