Hi Pavan,

You might want to check if the PR on the foil is treated properly and
the foil is in good shape. Some more information can be found at J.
Micromech. Microeng. 16 (2006), p. 23.

Hope this helpful. Thanks,

Fengyuan

At 12:41 PM 5/7/2009, Pavan Samudrala wrote:
>Hello all,
>
>I was wondering if anyone has any experience etching copper using CE-200. I
>am trying to use this chemical to spray etch Cu foils patterned using
>Shipley resist (S1818). After the etch I see some serious undercut (close to
>10um). The thickness of Cu is close to 1 mil (~25um). The etchant is at 35C
>and further experiments are to increase the etchant temperature and check
>the variation of the undercut. But was wondering if any of you has
>experience working with this chemical or for that matter any copper etchant
>that would give me lesser undercut.
>
>Thanks,
>
>Pavan Samudrala