Hi

  I need to etch out Pyrex glass for 1-5 micro meter.

  If the aspect ratio is good then I'll do 5 micro meter and if the aspect ratio
is bad then I'll etch only 1 micro meter or 100nm is OK.......

  Could anybody tell me your dry etching ratio and wet etching ratio for Pyrex
glass?

  I'll cover the wafer with S1818 which is not intended to etch out. I wonder
whether RIE or wet etching do not attack the S1818 layer also.....

  Please give me a clue for this.

  Thanks,

  Sokwon