Topographic and structural evolution of etched Si samples

Wet chemical and electrochemical etching of doped Si samples is a promising technique with a variety of applications ranging from micro-mechanical manufacturing to profiles delineation in electronic devices. We have developed simulation tools specifically designed to support the optimization phase and the control of these processes. The morphologic evolution of sub-micrometric portions of the material is simulated at atomic level by means of a stochastic approach, in which the single atom detachment probability depends on its coordination status. Etching profile evolution is simulated using a level-set technique for propagating interfaces. The nano-structural features (e.g. surface status) of the etched material are accessible using an atomic level stochastic approach. The simulation results show a general agreement with the experimental finding on etched material characterization, capturing also many peculiar characteristics of the real profiles and nano-structures of the etched material.