Nik is right, using the standard Bosh process you will always have some
amount of scalloping.  However, for short etches (5um) there is a trick.
First lower your substrate temperature to 10C then turn off parameter
switching and run the passivation chemistry at the same time as the etch
chemistry.  You will have to play with the platen bias a bit but it may
work for your relativly shallow etch.

-Mike Martin
 U. of Louisville



>>> Nicolas Duarte  09/09/06 11:30 AM >>>
This is what DRIE does.  If you are using the Bosch process there is
no way to completely get rid of the scallops, but you can reduce them
by optimizing your process.  Higher substrate power and shorter
cycles should help out.

If you want to completely get rid of scallops I am told that the Cryo
process is a DRIE process that has no scallops (since there is no
cycling in that) but you need a special tool to do it (most DRIE
machines cannot switch between the two processes).