We present a hybrid particle-based Cellular Automaton/Monte Carlo (CA/MC) approach for simulation of electron and hole transport in semiconductor devices. In this implementation of the CA algorithm, the entire Brillouin zone is discretized using a non-uniform mesh in k-space, and a transition table is generated between all initial and final states on the mesh, greatly simplifying the final state selection of the conventional full-band MC algorithm. This method allows for fully anisotropic scattering rates within the full-band scheme, at the cost of increased memory requirements for the transition table itself. Good agreement is obtained between the CA model and previously reported results for the velocity-field characteristics and high field distribution function, which illustrate the potential accuracy of the technique. The hybrid CA/Monte Carlo algorithm is introduced to help alleviate the memory problems of the CA method while preserving the speed-up and accuracy. The self-consistent coupling of the carrier simulation algorithm with fast 2- and 3-D multi-grid poisson solvers is discussed, and aspects related to the multi-scale discretization of position space and time domain are stressed as well.
Joint work with Shela J. Wigger and Stephen M. Goodnick of Arizona State University.