could you advise what is adequate rinsing? I dip in SU8 developer for
20-30s then rinse with IPA. Is it the correct step?

I do notice the white stains if under-develop, for example, IPA rinse after
just 10s developing.


Thanks.

On Thu, Nov 10, 2011 at 7:55 AM, Andrew Sarangan wrote:

> I suspect the problem is due to under-development or inadequate
> rinsing. SU8 will create white stains if it is rinsed before fully
> developed. The same effect could happen if old developer is used.
> Since your roughness seems to extend up the wall to the top of the
> cured surfaces, in adequate rinsing could also be a factor.
>
> On Wed, Nov 9, 2011 at 12:01 AM, Xiaohui Lin
>  wrote:
> > I am using SU8 2005 on 1mm thick glass substrate coated with 50nm Cr/Au.
> >
> > spin coat 4krpm
> > bake 95C, 3min
> > exposure 8s
> > PEB:   65C, 7min
> > develop: 40s
> >
> > I am getting a pretty rough sidewall as the picture in the following
> link..
> >
> > Could anyone suggest what is the problem?
> >
> > Thanks.

--
Lin, Xiaohui
Ph.D. Program in Electrical and Computer Engineering
Nanophotonics and Optical Interconnects Group
Microelectronics Research Center
The University of Texas at Austin
E-mail: xiaohui.lin@mail.utexas.edu
Office: (512) 471-4349