The addition of Si or Cu or both to the Aluminum is for improved etching and
electromigration performance- nothing to do with bonding. In 1982 we had a
line that used pure Al pads

Shay


Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Jordi Teva
Sent: Tuesday, January 27, 2009 12:20 PM
To: General MEMS discussion
Subject: Re: [mems-talk] Aluminum Bond pad reference

the Al bond pads provided by the semiconductor industry are not pure Al,
they are alloys with others metals, mostly Cu, just to avoid the
problem you have..
I do agree with Morten¨'s proposal with the Gold layer..,  I think you
will have a layer of alumina as
soon as you place your chips in the ambient air...

Jordi