Hello all,

Over the past few weeks I've been trying to get a highly anisotropic silicon
dioxide etch recipe for 2 different feature sizes.  I was able to obtain
acceptable results on 0.5 micron features.  However the recipe didn't work so
well for larger (50 micron) features.  My current recipe is a CHF3/O2 chemistry
at very low power and flow rates.  My optimised etch for the small features has
no effect on the larger features other than decreased etch rate.

Thanks for any insight you can offer,
Frank