Hole Transport in Strained \Si0.5 \Ge0.5 QW-MOSFETs With \langle\110\rangle and \langle\100\rangle Channel Orientations.

Hole velocity and mobility are extracted from quantum-well (QW) biaxially strained \Si0.5\Ge0.5 channel metal–oxide–semiconductor field-effect transistors (MOSFETs) on silicon-on-insulator wafers. Devices have been fabricated at sub-100-nm gate length with \HfO2/\TiN gate stacks. A significant hole mobility enhancement over the strained Si mobility curve is observed for QW MOSFETs. We also discuss the relationship between velocity and mobility of the strained SiGe channels with high Ge content for \langle\100\rangle and \langle\110\rangle crystal directions. Whereas the mobility increases by 18% for \langle\100\rangle with respect to \langle\110\rangle, it translates into a modest 8% velocity increase. [ABSTRACT FROM AUTHOR]