Wet etching of glass

The purpose of this paper is to find ways to Improve the wet etching techniques used for glass etching. Essential elements of glass wet etching process such as: influence of glass composition, etching rate, influence of the residual stress in the masking layer, characterization of the main masking materials, the quality of surface generated using wet etching process are analyzed. As a result of this analysis an improved technique for deep wet etching of glass is proposed. A 500-/spl mu/m thick Pyrex glass wafer was etched through using a Cr/Au and photoresist mask, from our knowledge this is the best result reported. For an improved surface an optimal solution HF/HCl (10:1) was established for Pyrex and soda lime glasses. The developed techniques are currently used for fabrication of microfluidic devices on glass.