Hi Michael,

I've tried miture of BOE(6:1) and glycerol 5:3. The evaporated aluminium
still seems to be attacked, and the etch rate is very non-linear.
My guess is that the solution doesn't mix very well.

poly, you might want to try Silox Vapox from Transene. They claim it's an
optimized oxide etchant for a metalized wafer.  You can check their website.
Please let me know the result.

Yenchun Lee

----- Original Message -----
From: "ZICKAR Michaël" 
To: "polly" ; "General MEMS discussion"

Sent: Friday, October 07, 2005 12:17 AM
Subject: RE: [mems-talk] how to etch SiO2 without etching underlying
Aluminum


Hi polly,

BHF:glycerol 2:1 etches aluminium with a selectivity of 0.006 towards
thermal SiO2,
HF vapor phase etching etches aluminium with selectivity of 0.002. Check out
the publications and application on idonus.com.