Fabrication of Fully Relaxed SiGe Layers with High Ge Concentration on Silicon-on-Insulator Wafers by Rapid Melt Growth

Abstract

We demonstrate the fabrication of high-quality fully relaxed SiGe layers on a silicon-on-insulator (SOI) substrate by rapid melt growth. A compositional gradient and crystallographic defects are confined to a region between the relaxed SiGe and residual SOI layers. The degradation of surface roughness during rapid thermal annealing is suppressed by the capping SiO2 layer. The growth mechanism is discussed based on the phase diagram of the Si–Ge system and the depth profile of the Ge concentration.