Umer,

I agree with Kirt.  You may be forming a silicide.  When the metal is thin and
an alloy forms, its surface tends to be rough and looks spotty.

Sagi Mathai
Information and Quantum Systems Lab
Hewlett-Packard Laboratories

-----Original Message-----
From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On
Behalf Of Kirt Williams
Sent: Tuesday, January 27, 2009 8:27 AM
To: General MEMS discussion
Subject: Re: [mems-talk] LPCVD Polysilicon over metal

I made that mistake before, depositing LPCVD polysilicon at 610 C on titanium.
In later inspection in a SEM, I could see that I produced what was likely
titanium silicide on titanium.

You may  be producing platinum silicide (I don't know the reaction temperature
or time) or titanium silicide.

    --Kirt Williams