Defect reduction effects in GaAs on Si substrates by thermal annealing

Abstract

High quality GaAs films with dislocation densities of 2–3×106 cm−2 on (100) Si substrates have been obtained by thermal cycle growth using the metalorganic chemical vapor deposition method. Significant reduction effects of dislocation density in the GaAs layers on Si have been analyzed by a simple model, in which annihilation and coalescence of dislocations are assumed to be caused by dislocation movement under thermal stress. Relaxation of thermal stress in the GaAs films on Si during thermal annealing has also been observed.