The study of self-limited state profile and level set simulation of anisotropic wet etching on quartz

摘要

This paper reports that the stable self-limited profile can be characterized by the inflection points on etch rate curve of crystal orientation zone from the etched hemisphere experiment, which is different from the method based on searching local minimal and maximal etch rates on cross section plane in previous study. A recognition process is developed to obtain inflection points from the hemisphere experiment, combining with the 3D level set model, the approach allows a quickly locating all the possible self-limited etch planes, arriving at a close approximation to the desired structures, for instance the high aspect ratio and vertical side wall micro structures. Comparing with experiments, it successfully predicts complex facets on micro needle array and other micro structures etched on quartz wafers with good calculation accuracy.