REDUCTION OF DISLOCATION DENSITY IN MISMATCHED SIGE SI USING A LOW-TEMPERATURE SI BUFFER LAYER/

The reduction of the dislocation density in relaxed SiGe/Si heterostru ctures using a low-temperature Si(LT-Si) buffer has been investigated. We have shown that a 0.1 mu m LT-Si buffer reduces the threading disl ocation density in mismatched Si0.85Ge0.15/Si epitaxial layers as low as similar to 10(4) cm(-2). Samples were grown by both gas-source mole cular beam epitaxy and ultrahigh vacuum chemical vapor deposition. (C) 1997 American Institute of Physics.