The use of strained Si to improve carrier mobility is explored with Technical Computer Aided Design (TCAD) methods. Whereas conventional TCAD simulators are based on drift-diffusion models, here, a Full Band Monte Carlo simulator (FBMC) is developed, which delivers more accurate and refined electrical transport properties of strained Si, Ge, and their alloys. In the past, the use of FBMC methods was limited by their high demand for computation time, so that their main purpose in TCAD was to deliver accurate data for the calibration of less fundamental methods such as drift-diffusion. However, it is shown that due to the ever increasing availability of computational power and with the implementation of CPU-time efficient algorithms, FBMC can be used for the simulation of MOSFET devices. The necessary band structure data are obtained with the Empirical Pseudopotential Method (EPM). To improve the performance of EPM calculation and of FBMC simulation, it is important to take advantage of the symmetry properties of the Brillouin zone. Therefore, the symmetry properties under several strain conditions are investigated in detail.
FBMC is also applied to explore Blocked Impurity Band (BIB) devices. These photo detectors for the far infrared range are used mainly in space-based observation facilities. BIB detectors deliver high quantum efficiency in a volume considerably smaller than that in conventional photoconductors because of their much higher primary doping. The primary dopants form an impurity band, in which significant hopping conduction occurs. To block the dark current introduced by hopping carriers, the device features an intrinsicly doped region, referred to as the blocking layer. Some of the standard scattering models for Monte Carlo have to be extended to deliver good results for temperatures below 10K. For example, acoustic deformation potential phonon scattering, which is usually treated as an elastic process, is implemented in the simulator by using a more accurate inelastic formulation.