Hole transport in p-channel Si MOSFETs

Using a Monte Carlo method, we investigate hole transport in ultrasmall p-channel Si MOSFETs with gate lengths of 25 nm. The device simulator couples a 2D Poisson solver with a discretized 6×6 k·p Hamiltonian solver that handles the valence band-structure and includes the effect of the confining potential under the gate, thereby providing the subband structure in the channel region. Carriers in the source and drain regions are treated as quasi-3D particles and the band-structure information is included by solving for the eigenenergies of a more compact 6×6 k·p Hamiltonian. It is seen that band-structure calculations are needed in order to describe accurately the high field transport in ultrasmall nano-scale MOSFETs.