X-ray double-crystal diffractometry characterization of semi-insulating GaAs

Abstract

The X-ray double crystal diffractometry method was employed to measure variations in dislocation densities, and normal residual strains in undoped, and indium-doped semi-insulating GaAS wafers grown by the liquid-encapsulated Czochralski technique. Low thermal gradient growth conditions, and indium doping decreased dislocation densities significantly. The distribution of dislocation densities was similar to the variation in EL2 concentrations. Normal residual strains were high in the undoped sample grown under the high thermal gradient growth conditions. The strain values were considerably lower in the undoped sample grown under the low thermal gradient growth conditions. Indium doping increased the strain slightly.