pMOSFET Performance Enhancement With Strained \Si1 - x\Gex Channels.

The inversion-layer hole mobility in MOSFETs with thin silicon–germanium (\Si1 - x\Gex) channels grown pseudomorphically on Si is calculated using a self-consistent \6 \times \6\ k \cdot p Poisson–Schrödinger mobility simulator calibrated to experimental and simulation data. The addition of uniaxial compressive stress to the inherent biaxial compressive strain of the pseudomorphic \Si1 - x\Gex layer is found to further enhance hole mobility by up to 2.5\times. Two-dimensional device simulations are used to assess the benefit of the \Si1 - x \Gex heterostructure channel for boosting the on -state current (Ion) of p-channel MOSFETs with a gate length (Lg) of 18 nm; the results show a moderate (10%–40%) improvement over a bulk-Si MOSFET. [ABSTRACT FROM PUBLISHER]