Dislocation reduction in GaAs on Si by thermal cycles and InGaAs/GaAs strained-layer superlattices

The etch-pit density of epitaxial GaAs layers grown on Si was significantly reduced by using the technique of growth interrupt and thermal cycles ( in situ TC) followed by growth of In 0.1 Ga 0.9 As/GaAs strained-layer superlattices (SLS's). The etch-pit density of 1.4×10 6 cm -2 (density of small pits by molten KOH etching) was achieved in 3.5 µm-thick GaAs epilayers. It was also found that the effect of SLS's on dislocation reduction was more enhanced by combining with the in situ TC process than the effect when SLS's were used by themselves.