An ethylene glycol/ aqueous HF solution will tend to be gentler on aluminum.
If you do a Google search on "ethylene glycol hf aluminum" you'll get quite
a few useful hits. The first hit is a posting to this newsgroup in Feb 2003.

Bill Eaton, Ph.D.
Materials & Analysis Manager
NP Photonics
mailto://[email protected]

> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of bobo
> Sent: Wednesday, May 14, 2003 9:31 PM
> To: [email protected]
> Subject: [mems-talk] Etching SiO2 without affecting Aluminum
>
>
> Dear all,
> does anyone knows what wet etchant can etching silicon
> dioxide without etching aluminum at the same time?   Thanks.
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