Omega-Gate p-MOSFET With Nanowirelike SiGe/Si Core/Shell Channel

Abstract

We demonstrated, for the first time, p-MOSFETs (L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> ges 40 nm) with SiGe/Si core/shell channel integrated on bulk Si using a CMOS-compatible top-down processes. The Omega-shaped nanowire (NW)-like channels comprised of ~12-nm-thick inner SiGe core and 4-nm-thick outer Si shell. The devices exhibited good subthreshold characteristics (with SS ~128 mV/dec), suggesting successful surface passivation of the SiGe NW body by the outer Si capping layer. Drive currents of ~167 muA/mum is achieved, which is 15% enhancement over the reference Si-channel devices fabricated by the same process. Double g <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> peaks are observed at low drain bias for the core/shell SiGe NW devices, confirming the quantum confinement of holes in the SiGe inner core.