Maybe you can use lengths of drawn metal wire?
I would imagine this would give a better thickness tolerance than metal sheets.

On Wed, Nov 12, 2008 at 08:43, Nicolas Vergauwe
 wrote:
> Hi everyone,
>
> Could you suggest me a spacer material for separating two (horizontal) glass
> plates? The spacer should have a thickness of 100 µm, but more importantly,
> the thickness tolerance should be as low as possible. Also, the spacer needs
> to be fixed manually on the glass plate: it cannot be processed on the glass
> plate but it has to be attached afterwards.
>
> I thought of using a thin metal sheet and then glue it to the glass plate,
> but I don't know if it will be the best way.
>
> Any help or ideas are welcome!
>
> Nicolas
>