Study of plastically deformed semiconductors by means of positron annihilation

Deformation-induced defects have been studied by means of positron annihilation. Temperature-dependent positron lifetime spectroscopy indicates the presence of dislocations acting as shallow positron traps. The decomposition of the lifetime spectra provides positron lifetime components related to vacancy clusters and mono- or divacancies. The correlation between positron measurements and electron paramagnetic resonance gives evidence that the Ga_As antisite is formed during plastic deformation. The density of point defects is estimated for different deformation conditions.