Metal-InGaAs contact resistance calculations from first principles

The metal-semiconductor contact resistance is an important factor in the performance of MOSFETs and a detailed understanding of the contact resistance is necessary in order to simulate and eventually optimize the devices. In this work we calculate metal-InGaAs contact resistances using Density Functional Theory (DFT) combined with non-equilibrium Greens function (NEGF) methods as implemented in Atomistix ToolKit (ATK). We have calculated specific contact resistivities, p_c, of metal-InGaAs and metal-InAs interfaces, where the metals studied are Ti, W, and Mo. We find that pc is approximately inversly proportional to the doping density with values that are in close agreement with experimental results from the literature.