The Computer Micro-Simulation Of Silicon Crystal Anisotropic Etching

Crystalline silicon anisotropic etching is one of the key techniques of MEMS processing. It is significant to have a precise simulation with the result of the anisotropic etching for the setup of MEMS computer aided design system and enhancement of MEMS technical capability.In this paper, a three-dimension dynamic simulating system for silicon anisotropic etching process has been set up with the use of OpenGL technique under VC developing environment. It demonstrates the dynamic process of silicon etching and shows the etching results for different masks of silicon bulk. With the guidance of the simulating system, an attempt is made to analyze, research and design the convex compensation methods for different masks of silicon anisotropic etching. And it agrees farely with the experimental figures.This system creates the etching model and the interactive operation between interfaces and users and accomplishes three-dimension dynamic demonstration of the etching process. The etching model consists of the creation of silicon base and the etching algorithm. In the former, the number of crystals on the silicon base is input by users at the beginning of the etching and automatically increments on needs as the etcing goes. In the latter, the etching process is referred to as the removal of atoms, which depends on the status of the four bonds attached to the atom. It is mentioned in the reference that the broken rate of bonds is determined by bonds density and surface active energy, with etchant concentration and temperature as its two facters. Hence a micro simulating software for silicon anisotropic etching is set up with the etching mechanism. Three different compensation methods are designed according to the theory on convex masks and prove to be appropriate with explicit experiment figures, which contribute to the computer realization for compensation algorism of convex structures.