> I am etching a microfluidics channel into Corning 2947 soda lime glass > using a 1:1 mixture of (BOE 6:1) : (BOE 10:1) from Baker. I haven't worked with this kind of glass. My experince is only on #7740. Annealing and etchant are two aproaches. You don't need NH4F in your etchant, for you don't use photoresist. Using H+ to adjust the F- concentration works well in #7740. (50%HF:69%HNO3:H2O at a volume rate of 2:1:2). About glass annealing, please also refer to Fan, Z.H. and Harrison, D.J., 1994, Anal. Chem. 66:177-184. Some of my glass wafers need this annealing process. But recent wafers don't need this process. Good luck, Dr. Zhen YANG Surface & Interface Technology Division Department of Manufacturing Systems Mechanical Engineering Laboratory Namiki 1-2, Tsukuba JAPAN 305-8564 TEL: +81-298-61 7209 FAX: +81-298-61 7167