3D Feature-Scale Simulation of Sputter Etching with Coupling to Equipment Simulation

Feature-scale simulation of sputter etching has been coupled to equipment parameters by means of transferring angular distributions of ions as provided by equipment simulation to our simulation code. Etching is modeled by performing ion flux integration for all node positions on a discretized 3D surface, taking into account shadowing by the geometry, the angular distribution of ions, and the sputtering yield. For rotationally symmetric geometries, a numerically and geometrically independent approach has been used to validate the 3D code. The application to 3D geometries is demonstrated for an L-shaped mask over a substrate for a resist mask geometry obtained from external lithography simulation.