High mobility Ge-channel formation by localized/selective liquid phase epitaxy (LPE) using Ge+B plasma ion implantation and laser melt annealing

Abstract

Localized Ge and SiGe high mobility channel material is needed for 10nm node and beyond CMOS technology. Thin direct >50% SiGe selective epi followed by oxidation for Ge condensation, 100% Ge selective epi or thermal mixing are methods that require a hard mask and epi interface defects with rough surfaces are always an issue. An alternative approach to epi is using photoresist masking as proposed by Borland et al [1] with Ge-infusion doping (dose controlled deposition), a very high dose implantation technique that leads to amorphous deposition followed by low temperature SPE of the amorphous Ge surface layer but residual interface defects remained.