Peng

I just had a bad experience with SU8 and humidity.  Ours was up to 55%.  I
tried spincoating Si wafers with SU8.  It looked good, but shortly after,
I found it all beaded up on the wafer.  After we fixed the humidity, it
worked fine.  It should normally be around 10%.

Eric


Eric Johnston
Department of Bioengineering
University of Pennsylvania


On Mon, 24 Mar 2008, Peng Li wrote:

> Dear all,
>
> I am fabricating SU8 molds on silicon wafer. The humidity is not well
> controlled in our fab. When it is below 20% percent, the adhesion is good.
> However, I find the effect of dehydration bake is very limited when the
> humidity is above 30%. I think the moisture condensed to the surface
> immediately after I take the wafer off the hotplate. I don't know what's
> the humidity when other people fabricating the SU8 mold. I am wondering
> whether anybody have any success in such humidity.
>
> I am thinking of using AP300 as adhesion promoter between silicon wafer
> and SU-8 molds. I see we had a lot of discussion here before. Could
> someone give me a standard operation procedure to start with?