Prediction of new etch fronts in black silicon produced by cryogenic deep reactive ion etching

This paper presents an explanation of the dynamic formation of black silicon (BSi) during deep reactive ion etching (DRIE) processes which has been confirmed by both experimental data with cryogenic DRIE and computational modeling. The model described the strong dependence of the substrate topography on the etching parameters and its evolution with process time. It shows the importance of the self-shadowing effect on the final structures and allows predicting the most important aspects of the BSi phenomenology such as the new etching fronts appearing at topographical saddle points during the incipient stages of BSi development.