Some suggestions:
Make sure the development is complete.  Also, use a Oxygen
descum prior to depositing metal.

We regularly make Ni/Au contacts to GaN without any problems.

Why do you heat the sample in-situe for 1 hour?  I have never
heard of this.  But I don't think it would effect the
adhesion.
-Bill

---- Original message ----
>Date: Tue, 15 Jun 2004 14:26:19 +0100 (BST)
>From: hare krishna 
>Subject: [mems-talk] Sticking of Ni/Au with Si and p-GaN
>To: General MEMS discussion 
>
>
>Hi to all,
>
>   Can anybody suggest me on this problem...i deposited
first Ni(40nm) and then Au(80nm) on both Si and p-GaN under
high vacuum after patterning for the Lift-off process...but
at the time of Lift-off the whole deposited metal got
stripped off...actually after deposition at room temperature
i just heated the sample in-situ (in vacuum) at 100C for one
hour...Is this the problem of sticking of Ni with Si and p-
GaN or some other problem...Actually i want to make ohmic
contact to p-GaN by Ni/Au as metal system...Suggest me...
>
>Thank You
>
>Hare Krishna
>
>M.Tech Student, IIT Kanpur
>
>
>
>
>Yahoo! India Matrimony: Find your partner online.
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