Michael,

According to my CRC Handbook of Metal Etchants, boiling aqua regia
will remove platinum but I don't know how the resist will handle it.
(Saito, R et al - J. Electrochem Soc. 132, 224, 1985)

You could also try molten sulfur or hot sulfur vapors, also mentioned
as attacking platinum, but I wouldn't recommend it.

Good luck!

-Reid

>


>>>>>>----*----<<<<<< Start of Forwarded Message >>>>>>----*----<<<<<<
>Dear all,
>
>is there anyone, who has worked on structuring platinum with wet
>etchants? I have tried aqua-regia (3parts HCl, 1part HNO3) of 36 %,
>but could not remove any Pt from my wafers. I am using ordinary
>resist on top of the Pt for structuring.
>
>Any suggestions on aqua regia or other chemicals that could etch
>Pt are greatly appreciated.
>
>Regards,
>
>Michael
>==================================================
>| Michael Koch                                   |
>| University of Southampton                      |
>| Department of Electronics and Computer Science |
>| Southampton SO17 1BJ                           |
>| England                                        |
>|                                                |
>| Tel.: +44 (0)1703 593737                       |
>| Fax.: +44 (0)1703 593029                       |
>| email: M.Koch@soton.ac.uk                      |
>==================================================
>
>


--
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|Reid (Turtle) Alyn Brennen                Hewlett-Packard Laboratories|
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`