High-performance germanium ω-Gate MuGFET with schottky-barrier nickel germanide source/drain and low-temperature disilane-passivated gate stack

Abstract

We report high-performance p-channel $\Omega$-gate germanium (Ge) p-channel multigate field-effect transistor (MuGFET) with low-temperature Si{2}\hbox{H} 6 surface passivation and Schottky-barrier nickel germanide (NiGe) metallic source/drain, fabricated on high-quality germanium-on-insulator (GeOI) substrates using sub-400 $^{\circ}\hbox{C} $ process modules. As compared with other reported p-channel multigate Ge devices formed by top-down approaches, the Ge MuGFETs in this letter have a record-high on-state current $I \rm ON of $\sim \hbox{450}\ \mu\hbox{A}/\mu\hbox{m}$ at $V{\rm GS} -V{\rm TH} = -\hbox{1}\ \hbox{V}$ and $V{\rm DS} = -\hbox{1}\ \hbox{V}$. High peak intrinsic saturation transconductance of $\sim \hbox{740}\ \mu\hbox{S}/\mu\hbox{m}$ and low off-state current are reported. We also study the effect of fin or channel doping on Ge MuGFET performance. The simple MuGFET process developed using GeOI substrate would be a good reference for future 3-D Ge device fabrication. © 2012 IEEE.