Ab initio model of carrier transport in diamond

We have investigated the carrier-transport properties of diamond using a first-principles approach. We have employed a full-band Monte Carlo model based on an electronic structure obtained from density-functional theory (DFT) augmented with Heyd-Scuseria-Ernzerhof (HSE) hybrid functionals. We have computed the carrier-phonon interaction directly employing the DFT electronic structure and phonon dispersion. Effective acoustic and optical scattering models have been calibrated against the ab initio results to obtain a computationally efficient transport model that retains the accuracy of the first-principles approach. Using the DFT-derived full-band structure and the calculated carrier-phonon scattering rates, we have evaluated the field-dependent drift velocities and impact-ionization coefficients and compared them to the available experimental data. We have also analyzed the temperature dependence of the carrier drift velocity up to 500 K and developed analytical models that can be used to perform device simulation based on the drift-diffusion method.