Two-sided wet chemical etching simulation of silicon

An isotropic wet chemical etching of silicon plays an important role in the realization of three dimensional micro electromechanical system structures (MEMS) like membranes and cantilevers. Many factors such crystal orientation, etchant composition, temperature, and doping influence the etching rates. Therefore the prediction of the etching result can be sometimes very difficult. In this work a new approach to simulate negative sloped planes, which often appear underneath convex mask cornets in wet chemical etching of semiconductors, is represented. Additionally the two-sided wet chemical etching of silicon wafers is simulated. In order to investigate the quality of the simulation method we presented simulated and experimental results of the etching system Si in KOH. Good agreement between both results can be observed. (author)