Fabrication of Silicon Microneedles Based on Anisotropic Wet Etching Technique

摘要

This paper presents a method to fabricate silicon microneedles with aspect ratio by employing anisotropic etching using KOH solution,and also presents the design of technical process of silicon microneedles. Through a series of experiments, we investgate various aspects that have effects on the formation of silicon microneedles during etching. Moreover, the temperature and concentration of etching solution and the concentration of IPA are studied to determine the effects on results of etching and wall-shape of silicon microneedles. When using 50% KOH (KOH 150g, water 150ml) solution in the condition of 87oC water bathing and etching 150min, the silicon microneedles are composed of {411} crystal-lattice plane (inclination 76.37°, height of 100μm).