Image Number 2 for United States Patent #8128749.
An SOI substrate has a gettering layer of silicon-germanium (SiGe) with 5-10% Ge, and a thickness of approximately 50-1000 nm. Carbon (C) may be added to SiGe to stabilize the dislocation network. The SOI substrate may be a SIMOX SOI substrate, or a bonded SOI substrate, or a seeded SOI substrate. The gettering layer may disposed under a buried oxide (BOX) layer. The gettering layer may be disposed on a backside of the substrate.