Yoshi, If you have Au/Ti then the Ti form a VERY stable oxide. It is most likely that NOT the Au that is oxidizing. Au does not WANT to oxidize, Ti does. Gary -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org]On Behalf Of Gabriel Matus Sent: Friday, March 13, 2009 2:12 PM To: mems-talk@memsnet.org Subject: Re: [mems-talk] Gold Oxide Yoshi, Oxygen plasma can oxidize the surface of gold. If that's what you have, then 15 seconds in BOE or 30 seconds in an SF6 plasma will etch the oxide. If that's not what you have, then you'll have to do XPS or some other chemical analysis to try to identify it. Gabriel