Thanks for your suggestion. I redid my experiment, the result turned out to be
much better. This time 1) I use Chrome as seed layer, 2) Bigger copper plate as
anode, 3) the current density is about 10ASF. 4) The substrate is glass slide.
5) The solution I used is EPI E-Brite Ultra Cu.

This time the copper did grow on the seed surface proportionally to the plating
time. However I still have some problems: 1) When the plating time is less than
90 seconds. The surfaces seem fine. When exceeding 90 seconds, the surfaces
trend to swell. 2) The plated surface was pretty rough.

Did the swollen problem have anything to do with the glass substrate ? And was
the rough surface a result of unclean seed surface ? I didn't do the plating in
the clean room but in the regular lab.

Thanks for your patience to read my mail.
Best regards
J.J. Wang


"g.balsubra manian"  wrote:
Copper should be beter as seed layer than aluminium
because of the low EMF of the aluminium involved.

Then What is your curent density or what current you
applied for the area???...If you apply in Nanoamps or
C.D is lesser then by faradys laws,the deposition time
takes much longer..What anode u used??wither soluble
opper anode or insoluble stainless steel or lead or
inert anodes???..

The plating is quite easier to do provided you have to
take of C.D and anode..Be cautious that your anode
should be llargr than cathode for unifrom step
coverage..