Layer transfer of low defect SiGe using an etch-back process

摘要

A method for forming strained Si or SiGe on relaxed SiGe on insulator (SGOI) or a SiGe on Si heterostructure is described incorporating growing epitaxial Si_1-yGe_y layers on a semiconductor substrate, smoothing surfaces by Chemo-Mechanical Polishing, bonding two substrates together via thermal treatments and transferring the SiGe layer from one substrate to the other via highly selective etching using SiGe itself as the etch-stop. The transferred SiGe layer may have its upper surface smoothed by CMP for epitaxial deposition of relaxed Si_1-yGe_y, and strained Si_1-yGe_y depending upon composition, strained Si, strained SiC, strained Ge, strained GeC, and strained Si_1-yGe_yC or a heavily doped layer to make electrical contacts for the SiGe/Si heterojunction diodes.