Dear group,

I etched 7 microns of glass in 6:1 BOE which had 100 nm of Cr as a mask. I
could etch the glass but had some pitting in Cr. Does anybody has any
experience with etching in 60:1 BOE, or 30:1 BOE. Will that be a better
choice? Can I etch longer in more dilute BOE to still etch 7-8 microns of
glass but saving the Cr mask.

Sincerely,
Pari.