Influence of defects on diffusion length inhomogeneity in gaas-te wafers

Abstract

Homogeneity, distribution and nature of defects in GaAs:Te wafers with different doping concentrations have been investigated by SPV (Surface PhotoVoltage) and EBIC (Electron Beam Induced Current) methods. The resulting radial distribution of the minority carrier diffusion length L across each wafer has been correlated with the profiles obtained for dislocation density and N-D-N-A. By comparing the present results with previous cathodoluminescence analyses (Mendez et al. 1988, Mendez et al. 1991), it is suggested that dislocations and dislocation related centres determine the L values.