Defects in electron-irradiated germanium

The growth and structure of defects in electron-irradiated Ge has been followed at room temperature and at higher temperatures between 200° and 300°C. At room temperature, small interstitial loops of approximately edge character on {311} planes are observed and eventually grow into dendritic structures. At the higher temperatures, rods elongated along the 〈110〉 directions form first but then tend to widen into plates of interstitial type on {311} planes with a displacement vector R = 0.04〈611〉. It is possible that all of these defects are of the same type and correspond to aggregates of Ge interstitials, but the possibility of impurity effects cannot be ruled out. The defects tend to transform into perfect dislocation loops on annealing.