Hi Madhav,

There is a couple of possibilities. A gold layer works well, about 10nm.
But you'll probably won't be able to see the underlying pattern still.

You can also try conductive polymers, of which AquaSave (Mitsubishi) and
eSpacer (Showa Denko) are but two examples, just Google them to find
additional information. These are spin-on polymers that can be latter
removed by water immersion. They might have a better chance of allowing
you to see through to the aluminium, esp. if you image at high voltage
on you system.

Mathieu

________________________________________________
Mathieu E.H. Foquet      mfoquet@pacificbiosciences.com
Senior Scientist             Pacific Biosciences Inc.
T.650.543.5007              F.650.323.9410
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