Michael,

It all depends on the recipe that you are using.  At 500 uTorr and 300
Watts I've experienced plasma etch rates greater than 1.25 um per
minute.

Lester Lopez
Research Assistant
Wireless and Microwave Research Group
Department of Electrical Engineering
University of South Florida
4202 E. Fowler Ave ENB 118
Tampa, FL 33620
Tel: 813-974-4851
Fax: 813-974-5250
lelopez@eng.usf.edu