Phase-space solution of the subband Boltzmann transport equation for nano-scale TCAD

We present a comprehensive simulation framework for transport modeling in nano-scaled devices based on the solution of the subband Boltzmann transport equation (BTE). The BTE is solved in phase space using a k·p-based electronic structure model and includes all relevant scattering processes. The BTE solver is combined with a conventional drift-diffusion-based simulator using a novel iteration approach. The pairing between BTE, DD, and Poisson results in a flexible toolkit which converges quickly in any mode of operation, allows large-scale parallelization, and to include near-equilibrium transport outside the BTE region, i.e. the contacting regions. The toolkit is commercially available as part of the GTS Nano Device Simulator (NDS). We examine realistic NMOS and PMOS devices, including transport at the microscopic scale and possible numerical approximations.