Sorry for the confusion- I would have sworn I had changed the "Subject"
line...

Allow me to add to my original answer.  I am quite sure this is what is
happening, though I am a little surprised that it would occur for a 1000
angstrom film.  Gurvinderjit- are you sure of this thickness?

I used to make a form of tunneling sensor just this way- depositing 300-500
angstrom gold films on a glass slide, then heating the suface until the
uniform gold film broke apart and migrated to form discrete but closely
spaced "islands".  I then filled the space in between with one of several
organic semiconducting films to enhance the tunneling efficiency as they
were exposed to various VOC's.

Hope this helps.

marc

> -----Original Message-----
> From: Marc Straub [mailto:marc.straub@coventor.com]
> Sent: Monday, May 20, 2002 10:17 AM
> To: mems-talk@memsnet.org
> Subject: RE: mems-talk digest, Vol 1 #291 - 7 msgs
>
>
> Gurvinderjit,
>
> I suspect that your film is "beading" like water on a waxed
> surface and forming into discrete gold islands.  Gold does not
> wet or adhere to oxides well, particularly in very thin layers.
> Heating the surface gives the Au atoms the energy they need to migrate.
>
> Depending upon your application, you should try a thicker layer
> and/or flashes (thin layers) of Cr/Cu, Ti or Ti/W under the Au
> for better adhesion.  Good luck.
>
> --
> Marc Straub
> Staff Engineer, Product Development Services
> Coventor, Inc.  (Formerly Microcosm Technologies)
> 7 Corporate Park, Suite 260
> Irvine, CA  92606
> Ph: 949-756-0033  Fax: 949-756-0070
> marc.straub@XXXXcoventor.com  [remove the "XXXX"]
>
>
> > -----Original Message-----
> > Date: Mon, 20 May 2002 11:20:15 +0530 (IST)
> > From: Gurvinderjit Singh 
> > To: mems-talk@memsnet.org
> > Subject: [mems-talk] Gold film
> > Reply-To: mems-talk@memsnet.org
> >
> > Dear friend i have one query.
> > I am depositing gold film (thickness 0.1 micron)by thermal
> evaporation on
> > oxides,
> > but when  i am annealing my sample to 700K this gold film become non
> > -conductive may be  duo to formation of gold oxide. But from
> > literature i found
> > that gold should not become oxide till 1200K. I also read people using
> > gold electrodes (thin film by thermal evaporation) on their samples and
> > work till 900k kindly let me know where i am doing mistake,
> wether to take
> > more thick film or something else.
> >
> >
> >
> > __________________________________________________________________
> > _____________
> >
> >
> >    Gurvinderjit Singh Ahluwalia             Tel: +91-0731-488656
> >      Laser Materials Division               Fax: +91-0731-488650
> >    Centre for Advanced Technology         email: gjit@cat.ernet.in
> >    Indore - 452 013  INDIA