A Hybrid Mesh Generation Method for Two and Three Dimensional Simulation of Semiconductor Processes and Devices

We present a hybrid mesh generation algorithm, which has been developed for semiconductor process and device simulation. The method uses Cartesian elements (bricks or hexahedra in 3D and rectangles in 2D) whenever possible and non-Cartesian elements (prisms and tetrahedra in 3D and triangles in 2D) are only introduced when necessary to resolve material boundaries or other features of interest. Our approach utilizes a quadtree-octree data structure with a level set representation of material boundaries. This combination allows for an efficient and robust tracking of complex moving boundaries. Efficiency is obtained by localizing non-Cartesian grid generation and by obtaining fast connectivity information from the quadtree-octree data structure. Robustness is provided by the level set formulation, which easily handles topologically difficult interfaces, such as regions which begin simply connected but lose this connectivity after boundaries merge. Following a discussion of the method, results are presented.