A flexible way for meshing geometries is possible by tetrahedral meshing. There are almost no limitation on the geometries and the direction of the geometry edges is not subject to any restrictions.
The most important discretization methods in semiconductor process and device simulation are Box Integration and the Finite Elements method. The problems under consideration, such as electrical device simulations of semiconductor devices and diffusion simulations of implanted dopants, impose certain requirements on the grids. Basically it seems possible that both simulation problems can be solved by both discretization methods. However, most device simulators (MINIMOS [6][11], DESSIS [33], MEDICI [68]) use the Box Integration method, which will be examined in Chapter 3, whereas diffusion simulation is usually done by Finite Elements.