Try searching Google with "copper hydrofluoric acid etch rate mems" .
There's a paper with a 5:1 BHF etch rates listed for many metals and other
materials.

----- Original Message -----
From: "Tan, Chuan Seng" 
Subject: [mems-talk] HF and Cu

> Can anyone tell me if diluted HF (say 1:20) attacks Cu ? And does Acetone
> do anything to Cu ?