MOSFET hot-carrier induced gate current simulation by self-consistent silicon/oxide Monte Carlo device simulation

Hot electron transport in MOS transistors is investigated by means of a coupled silicon/oxide Monte Carlo (MC) simulation. First, a new MC simulator able to handle selfconsistently different materials is developed. Then, the impact of oxide transport on the gate current (I_G) is analyzed comparing different injection models with experiments. It is shown that oxide transport plays an important role on I_G when the gate voltage is below the drain voltage (V_GSDS). In this condition, coupled silicon/oxide (SI+OX) simulation is important to quantitatively assess I_G. It is also shown that oxide scattering in the image force potential well does not significantly reduce I_G. Furthermore, we propose a new injection model that empirically accounts for oxide scattering and that provides the same I_G of the SI+OX model, but with the simulation of the silicon channel only, thus enabling a significant reduction of simulation time.