Hi,
I am doing gold pattern on polyimide. The following is
the pordedure,
Spin coat polyimide on si wafer, pattern it, cure it
for 1 hour at 120 degC.
deposit cr and gold using ebeam.
spin coat photoresist, pattern it.
wet etch gold and cr.

I found that the gold etchant will attack polyimide.
When I dip the wafer into gold etchant, the color of
polyimide will be changed from green to brown, and
some small hole appears on polyimide. It will affact
the adhesion of cr and polyimide. The metal layer is
easy to be peeled off.

Thanks,

zlk
Yahoo! Health - Feel better, live better
http://health.yahoo.com