12.10 Summary

Topography simulation for semiconductor manufacturing can be divided into two main parts: into modeling the transport of the gas species above the wafer and the subsequent surface evolution determined by the fluxes and concentrations of the species.

The ELSA simulator was applied to several topography simulations requested by industrial partners. The shape silicon dioxide and nitride films occurring in backend manufacturing processes are simulated accurately including the formation of voids. The silicon trenches are part of power MOSFET s and memory cells. The voids determine the capacitance of the interconnect lines, which is crucial for the performance of the devices. All observed effects match in the SEM pictures and in the simulation results.