Maybe you can try SU8? There is plentiful information on the web on this
popular resist. For example:

http://www.chestech.co.uk/mccsu8.htm (additional details for your
application by clicking on datasheet links)

Fred
----- Original Message -----
From: "Jessica Melin" 
Subject: [mems-talk] Thick Positive Photoresist (100um)

> I am trying to find a good recipe for achieving 100um thick positive
> photoresist on silicon wafers. Currently, we are trying a two layer
> process using AZ50XT but there are major problems with poor adhesion of
> the resist after developing (even when HMDS is used and the resist is left
> overnight to rehydrate). Would appreciate any help on a successful recipe
> using AZ50XT or what other positive photoresist could be used. Please
> contact me as soon as possible. Thank you in advance,