Hi Prem,

The SU-8 will peel off faster with higher solution temperature and
longer immersion time. I didn't do experiments at <60 deg C, but I can
imagine the structures won't stand much of a chance remaining attached
to the substrate beyond a few minutes at temperatures above RT. The
chemical bond at the substrate-SU-8 interface is attacked in solution,
and peeling is promoted by a residual (tensile) stress state in the
film.

I'll dig up some more SEM pictures, and send them to you later in the week.

Regards,

Michael

> ---------- Forwarded message ----------
> From: "Prem Pal" 
> To: 
> Date: 7 May 2008 02:46:16 -0000
> Subject: Re: [mems-talk] SU-8 structure using wet etching
> Hi Michael
>
> Thank you for your suggestions and providing references. If you have the SEM
other than published in your papers, please send.Do you have any experinece of
SU-8 peeling off if the KOH etching is performed at temperature lower than 60 C.
>
> Best regards
>
> Prem