Performance analysis of p-type silicon nanowire FETs with silicon-germanium cladding

The performance of p-type silicon nanowire FETs with three different silicon-germanium cladding options is bench-marked against the silicon reference device. Low-field mobilities and full device characteristics are obtained from the solution of the subband Boltzmann transport equation, including phonon and surface roughness scattering. The subband dispersion is calculated using 6kp band structure model, including the strain induced by the cladding layer. We show that silicon nanowires can be outperformed due to the superior hole mobility of strained silicon-germanium, but the off-state behavior degrades with increasing cladding thickness.