Process Simulation

In this chapter an outline of the very diverse topic of process simulation is given. This includes the process steps of ion implantation and thermal annealing, which introduce, activate, and modify dopant distributions, and the process steps lithography, deposition, and etching, which are used to structure the semiconductor wafer. The section on oxidation deals with the simulation of the oxide growth, whereas the aspect of dopant segregation is included in the section on diffusion. Finally, the impact of process variations is outlined. Overall, the process simulation chapter primarily deals with the physics and the related models for the various process steps, whereas the discussion of generic algorithms, e.g., for the solution of partial differential equations, is left for another dedicated chapter of this book. However, some algorithms which are specific for process simulation are also briefly described in this chapter. Due to the diversity of the area of process simulation, this chapter could not strive for completeness in the presentation of the physical models. We largely refer to silicon technology, whereas most models can also be applied for or adapted to other top-down semiconductor technologies where, in contrast to bottom-up technologies based on self-assembling, patterning steps, ion implantation and high-temperature process steps are used to generate three-dimensional geometries and dopant distributions.