Wet Chemical Etching for Glass Micro-Machining

In this paper, wet etching of Pyrex Glass using different chemicals is presented. The advantages as well as disadvantages of each method are presented and discussed in light of the experiments. The etch rates of Glass in different dilutions of HF (Hydrofluoric Acid) and BHF (Buffered Hydrofluoric Acid) are reported. Different agitation techniques are applied during process and results are compared. The improvement in the etching uniformity is achieved by string the solution continuously during etching time. Etch rate of Glass in HF solution is much higher than BHF solution and can be controlled based on concentration. Samples are characterized using Universal Length Measurement (ULM) system and optical profiler.