Cathodoluminescence and transmission electron microscopic investigations were made of Cu-diffused material in order to determine the origin of bright and dark dislocation contrasts. Various forms of Cu agglomeration were found, depending upon the diffusion temperature and cooling rate. The bright dislocation contrast was attributed to an enrichment with CuGa acceptors, while the dark contrast was attributed mainly to the non-radiative recombination of Cu-As precipitates or to clouds of small dislocation loops.

H.S.Leipner, R.Scholz, F.Syrowatka, H.Uniewski, J.Schreiber: Materials Science and Engineering B, 1996, 42[1-3], 185-8