Optimization of deep wet etching borosilicate glass substrates technological process for biomedical applications

The paper presents a microcells on borosilicate glass substrate fabrication technology for used for biomedical applications. The fabrication technology improved the standard lithography and wet chemical etching processes. We have studied the masking layer and the etching solutions which allow obtaining a 90% light transmission in a large optical range (180-2500 nm) and a low optical absorption. The diameter of a cell is 20 μm and the depth between 4-8 μm. The best results were obtained using Cr/Au as masking layer and KOH 7M as etching solution for the borosilicate glass.