Epitaxy of In0.01Ga0.99As on Ge/offcut Si (001) virtual substrate

► In0.01Ga0.99As layers were grown on offcut Si substrate using Ge as buffer layer. ► Dislocation density of Ge-on-Si was inverse proportional to thickness square root. ► GaAs islands were observed in the 100 nm region on In0.01Ga0.99As/Ge interface. ► Unintended Ge-doping as low as 1016 cm− 3 was observed in In0.01Ga0.99As layer.