Virginia, H2O2 will not harm Au, Al, or alumina, in my experiences. A 30% H2O2 and water gives a fast etch rate but temperature control is critical. You must keep the temperature stable. Expect some under cutting. If you can not control the temperature, use a 10% solution. This will be slow but not under cut as much and isn't as temperature sensitive. Hope this helps. Brent Garber Virginia Soares wrote: > Dear listers, > > Could you tell me if there is any wet etchant for TiW that would not etch gold nor aluminium or alumina?We are thinking of using H2O2 and water but we do not have the possibility to make thick gold layer which makes it very difficult to determine slectivities. > > Thank you in advance > > Virginia Soares > INESC-Microsystems and Microtecnologies > Rua Alves Redol,9 > 1000-029 LISBOA > PORTUGAL > URL:www.inesc-mn.pt > > _______________________________________________ > MEMS-talk@memsnet.org mailing list: to unsubscribe or change your list > options, visit http://mail.mems-exchange.org/mailman/listinfo/mems-talk > Hosted by the MEMS Exchange, providers of MEMS processing services. > Visit us at http://www.memsnet.org/