Simulation program suitable for hot carrier studies: An efficient multiband Monte Carlo model using both full and analytic band structure description for silicon

Abstract

An efficient Monte Carlo model using both the full electronic band structure calculated from the empirical pseudopotential method and fitted, anisotropic, analytic bands is described. With the simulation program suitable for hot carrier studies, electron dynamics (i.e., scattering processes) are treated using the pseudopotential bands, where the accuracy of the band structure is most critical, while the electron kinetics (i.e., electron free flight between scattering and postscattering momentum selection) is treated using the fitted, analytic bands in order to greatly enhance the computational efficiency of the simulator. The analytic, multiband, multivalley model has 65 ellipsoidal, nonparabolic valleys and fits both the density of states and the electron E(k) dispersion relations of the pseudopotential band. The scattering ‘‘matrix elements’’ effect is also explored and an efficient model for this was developed and implemented for the first time in the framework of an analytic band. With this model, it is possible to include band-structure effects with greatly enhanced physical accuracy and central processing unit times comparable to other fitted band models. Excellent agreement is obtained between results using this new model and those from experiments and computationally more demanding simulators.