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Uneven / Step Ag Plating

2007

Hi all,
I am Raymond Lim Jit Tan as Leadframe Sr Plating Engr from Penang, Malaysia. I am incharging the whole spot ag reel to reel leadframe plating process operation . I desperately need some help and input here to resolve some chronic plating issue . I am struggling with uneven/step ag plating, which operate with very narrow process window.I have to control the anti immersion content at very low and operate at high ag current density 60-80asd with high speed ag plating but the result does not help consistently.Hope I can get some plating experts advise to put this issue to sleep.
Thanks and best regards.
Raymond Lim.

RAYMOND LIM JIT TAN
PLATING SR ENGR - PENANG, MALAYSIA

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Raymond, give us a chance to help you by tellng us what you do and how you do it - some real plating conditions would be rather helpful!

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2007

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2007

Hi Raymond
We need more informations to help you
What is the process used before the silver strike?
Is the base material pure copper?
Is it possible to add a cyanide copper underlayer in your process before the silver strike?
anyway you should try to act on the base material instead of the silver plating.

good luck!

Gimbert Guillaume
- Le Puy, France

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Step plating is usually caused by the brightener level being too low for the current density used. You have a couple of choices either increase the brightener level or use pulse plating to increase the current density. I ms on and 2 ms off is frequently used for spot silver

Pat Mentone
St Paul, Minnesota
2007