Leaving them to relax for 1 hour after spinning (before SB) may also help.
Wrinkles can also be due to low exposure dose but in this case would
only appear during PEB.


On Thu, Jul 3, 2008 at 04:55, Meifang Lai  wrote:
> Hi Lin,
>
> I am using SU-8 2050. I had similar problem before. I think the wrinkles and
> roughness may be due to contaminated substrate.
> I solved the problem by carefully cleaning the substrate using Piranha wet
> etch and dehydrating the substrate at 120C for 10 min.
>
> Good luck!
>
> Meifang
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]]
> On Behalf Of Li, Lin (MU-Student)
> Sent: Thursday, 3 July 2008 3:00 AM
> To: [email protected]
> Subject: [mems-talk] SU8-2075
>
> I have been using SU8-2075 to make 100um thick structure. But I have
> difficulty in reducing the wrinkles and the roughness.
> I tried 65C and 95C softbaking 5min and 10min each or even tried to cool
> down and bake repetively as the manual suggested.
> Could you let me know any recipe or methods to solve this problem?
>