Xinyu,
I had cracks and delamination in my SU-8 before I started to make any
PDMS replicas.  This was remedied in my case by decreasing the exposure
time.  You may want to try adjusting your fabrication parameters.

Glen

At 10:58 AM 4/12/2002, you wrote:

  Dear Colleagues,

  I am making and using mold out of SU-8 photoresist. The problem is
  that
  it cracks after several PDMS replicas. Would you please share what
  could
  cause this and how to avoid this.

  Thanks.

  Xinyu Li

*********************************************
Glen A. Landry, Ph.D.
Naval Research Laboratory
Materials Physics Branch
Code 6340
4555 Overlook Ave. SW
Washington, DC 20375
USA
Tel.: 202-767-4474 Fax: 202-767-1697
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