Quantum mechanical simulation of charge transport in very small semiconductor structures

A quantum-mechanical simulation method of charge transport in very small semiconductor devices is presented that is based on the numerical solution of the time-dependent Schrodinger equation (coupled self-consistently to the Poisson equation to determine the electrostatic potential in the device). Carrier transport is considered within the effective mass approximation, while the effects of the electron-phonon interaction are included in an approximation that is consistent with the results of the perturbation theory and gives the correct two-point time correlation function. Numerical results for the transient behaviour of a planar ultrasubmicrometer three-dimensional GaAs MESFETs (gate length of 26 nm) are also presented. They indicate that extremely fast gate-step response times (switching times) characterize such short-channel GaAs devices