Hi Thomas,
Try O2 RIE (Reactive Ion Etching) etch.
O2+SF6 should also work and give you higher etch rate.
I have used these for another type of polymer substrate so I am not sure =
whether it would work for PET.

Miss Ghazal Hakemi
PhD Student
Microsystems and Nanotechnology Centre (Building 70)
Cranfield University
MK43 0AL
tel. 01234 750111 x2583
________________________________

From: Thomas Reddy [mailto:thomasreddy18@yahoo.com]
Sent: Sat 19/04/2008 6:35 AM
To: mems-talk@memsnet.org
Subject: [mems-talk] PET

Hello
I wanna  to do  a  vertical etch  on PET  but every time i tried a lot  =
of  crack considered.
what should i do?
thanks