Processing Photo Definable Glasses Processing of photosensitive (photodefinable) glasses. Exposure to mid UV light, followed by a two step baking stage, then etching in HF acid. and finally an annealing stage. Nano and Micro Devices Center, University of Alabama in Huntsville. Produced by Khalid H. Tantawi and John D. Williams. Microfluidic Pump & Valve System A microfluidic pump and valve system. It's a 2-layer PDMS process, one for the liquid flow and one for the air pressure control. I think this was on silicon but glass is even easier. I don't remember the specific sizes of the channels but I want to say they are on the order of 80 microns. Become Partners with the NMDC! Be sure to visit our Partners page to learn what the NMDC can do for you!