It is true, Gold does not dissolve when used as an anode. That seems to be
the generally accepted fact in electroplaters community. That makes it even
more important to have a viable MEMS design including geometry of features
and/or "dummy sites" and, a good control of the process including equipment,
anode shape and location, mixing and solution quality.

Igor Kadija
[email protected]
www.fibrotools.com
201/670-8397


At 01:47 PM 1/29/02 -0500, you wrote:
>I would only add to this that current density is not always uniform across
>all plated areas if you have a photoresist mask and there are some very
>small features and some larger features.  The current can distribute itself
>so that the smaller features have a higher current density than the larger.
>
>Also, I'm not sure reverse pulse plating has any effect on gold - the gold
>plates out of solution, but it does not plate back into solution if the
>voltage is reversed.  (This is certainly true of the solution I use, which
>is  Enthone BDT-200 - does anyone know if it's true for all solutions?)   In
>other words, if you used a gold anode while plating, it would not lose any
>mass.
>
>David Nemeth
>Senior Process Engineer
>Sophia Wireless, Inc.
>14225-C Sullyfield Circle
>Chantilly, VA
>Ph: (703) 961-9573 x206
>Fax:(703) 961-9576