Hello All,

How to etch single crystal quartz? I tried HF (49%) at room temperture.
This had an etchrate of  only 3 um/h. I need to etch at least 40 um, and
I think my mask (Cr) will not withstand this long time. I also tried
ammonium fluoridel, this only etched 14 nm/h.

Does anyone have any suggestions ?

Thanks,

Oliver