| The state of the art for full-band Monte Carlo device simulation is advanced on two fronts. First, quantum effects are taken into account by including quantum corrections in the semiclassical Monte Carlo framework. A quantitative study of corrections based on the Wigner transport equation and the effective potential is performed, and the Wigner-based method is extended for use in MOS systems with an empirical model. Additionally, a new Monte Carlo quantum correction method is proposed based on the Schrödinger equation, and recommendations are given for practical use of the three corrections in the context of quantization and tunneling effects. The Schrödinger-based quantum correction methodology is also extended to device simulation. A 25-nm MOSFET is simulated self-consistently with the Schrödinger-corrected Monte Carlo model, and the importance of quantum corrections for highly scaled devices is demonstrated. The second focus of this work is the generalization of a silicon full-band Monte Carlo model to include silicon-based materials. A flexible and efficient device simulator is developed that is capable of introducing an arbitrary number, location, and grading of silicon-based material regions in a 2-D device. Different materials can be added by changing the bandstructure and scattering rate tables, with only cosmetic changes required in the internal code. As a test case, strained silicon is implemented and bulk strained silicon simulations are performed to verify agreement with experimental data. Exploratory device simulation results are also presented, which indicate that the enhanced performance of strained silicon devices extends to MOSFET scaling limits. |
