Dear Kevin Nichols,

Thanks alot for your comment. as you said maybe i shold buy a new one.
Now i am trying to heat the viscous SU-8 before spin coating and will check
whether it will work.

Regards


At 2011-04-21 04:13:35，"Kevin Nichols"  wrote:

>The 2000 series of SU-8 are formulated in cyclopentanone. If you want
>to dilute your stock yourself, use cyclopentanone, not IPA. I hope you
>have a mechanical shaker, or very strong arms.
>
>Alternatively, just buy the right formulation from Microchem, at the
>correct concentration and viscosity for the thickness you want. The
>series is numbered so that the last digits give the relative viscosity
>(i.e., SU-8 2100 is useful in the 100 micron thick range, and is more
>viscous than SU-8 25, which is useful in the 25 micron thick range).
>I'd highly recommend you just buy the concentration you need instead
>of trying to dilute it yourself.
>
>- Kevin