>From my experience, there are no aghesion problems between Pt-Ti-Pt-Au and
Pd-Ti-Pd-Au to GaAs
Several things to keep in mind: 1) remove oxide bevore deposition by a acid
dip (HCL, diluted 1:1; or BHF)
2) Start with Pt/Pd layer for a good contact resistance
3) from my experience (Pt 100A: Ti 400A: Pt 400A: Au) shows good contact
resistance to highly dopped p-GaAs (I couldn't find the reference right now,
but that was taken from a paper.. JVST I believe..  )

Mike

> -----Original Message-----
> From: Shashwat Kumaria [SMTP:[email protected]]
> Sent: Saturday, September 06, 2003 19:08
> To:   [email protected]
> Subject:      [mems-talk] GaAs adhesion to Ti-Pt-Au
>
> How can I improve the adhesion of the Ti-Pt-Au metallization to GaAs
> substrate? Ti adheres very well to substrates that have oxygen as one of
> the components in the substrate, but obviously this is not the case with
> GaAs.
>
> Can I oxidize the GaAs substrate to improve the adhesion? If yes, what
> impact will it have on the contact resistance?
>
> Thanks very much in advance for your replies.
>
> SK
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