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
>
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