Study of the heavy metal gettering effect of porous silicon on SOI structure

Gettering of copper and nickel in FIPOS SOI structures has been investigated using XTEM and SIMS for the first time in this paper. A transition region with dendrite porous oxidized Si exists at the interface between the Si oxidized porous layer (PS) and the substrate Si. This transition region may provide effective gettering sites for Cu and Ni which can diffuse from the top Si layer to the substrate during the SOI formation. In addition, Cu segregates to the transition region more readily.