Hierarchical Device Simulation

This monograph is intended for scientists and TCAD engineers who are interested in physics-based simulation of Si and SiGe devices. The common theoretical background of the drift-diffusion, hydrodynamic, and Monte-Carlo models and their synergy are discussed and it is shown how these models form a consistent hierarchy of simulation tools. The basis of this hierarchy is the full-band Monte-Carlo device model which is discussed in detail, including its numerical and stochastic properties. The drift-diffusion and hydrodynamic models for large-signal, small-signal, and noise analysis are derived from the Boltzmann transport equation in such a way that all transport and noise parameters can be obtained by Monte-Carlo simulations. With this hierarchy of simulation tools the device characteristics of strained Si MOSFETs and SiGe HBTs are analysed and the accuracy of the momentum-based models is assessed by comparison with the Monte-Carlo device simulator.