Simulation of Electrochemical Etching of Silicon with COMSOL

A. Ivanov
Hochschule Furtwangen
Furtwangen, Germany

Electrochemical etching of silicon (anodization) is a process that can be used for etching of forms of nearly arbitrary shapes. The difficulty of applying the process for mass production is in the many parameters influencing the process, such as electrolyte concentration and temperature, silicon substrate doping and type, and so on.

COMSOL as an FEM simulation tool is very suitable for modeling of such complicated multiphysical process as anodization. In the presented work so called edge effect of the anodization process, which results in higher etching rate near the edges of structures and formation of convex etch form, is modeled.