Selective Wet Etching in Fabricating SiGe and Ge Nanowires for Gate-all-Around MOSFETs

A selective wet etching process for fabricating SiGe and Ge nanowires for gate all around transistors is introduced in this paper. Two formulated proprietary chemical mixtures with highly selective etching properties (Si vs. SiGe and SiGe vs. Ge) can effectively dissolve the sacrificial layers with minimal damage to the interstitial nanowire materials. The Auger Electron Spectroscopy (AES) surface characterization indicates that no chemical contamination is left after the wet etching process.