Hello James,

Have you considered using SU8 or BCB negative resists?
Although 140°C might be above the glass transition temperature of SU8 (don't
remember for BCB), both resists withstand KOH etching.
Maybe you could try.

Best regards,

Edouard



On Wed, Aug 11, 2010 at 2:45 PM, James Paul Grant wrote:

> Hello all,
>
> Does anyone know of a permanent spin on 'glue' that is temperature stable
> (up to 140oC), KOH resistant, transparent and is not attached by acetone?
>
> It might help if I explain why I require such a glue:
>
> I'd like to permanently bond a lithium niobate wafer to a slicon wafer. The
> Lithium niobate wafer will then be lapped down to a thickness or around 10
> microns. Next I would like to etch a 1 mm by 1 mm window in the silicon
> structure such that the 10 microns of lithium niobate is essentially free
> standing.
>
> Has anybody got any experience of such a technique?
>
> Any comments are most welcome.
>
> James