Yes, the emulsion should be in contact with the SU-8, it won't work
well if it is on the other side of the plate millimeters away (unless
you have a very well collimated light source).

If you have problems with SU-8 sticking too much, you can always
transfer your pattern to a chromium coated glass/quartz plate with
conventional lithography and then you can clean your newly made mask
with acetone when it gets sticky. There are vendors who can supply
plates of glass ready for this procedure.

Best Regards,
Jon Fox

On Mon, Mar 16, 2009 at 5:36 AM, 郑瑞麟(Ruilin Zheng)
 wrote:
> Hello,
>
> I just bought some plastic mask, and I attached them onto a glass plate.
> I want to use these mask for contact lithography on SU-8 layer.
> I am wondering if the SU-8 layer would stick to the plastic mask after
> exposure. Or should I use the opposite side of the mask (i.e. glass plate)
> for contact with SU-8 layer?
>
> But in this way, the lithography won't be the contact one.
> Does anyone has that experience? Please give me some advices.

--
Dr. Jon R. Fox
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