Dear MEMS fellows,
does anybody know how much gold is actually consumed from the electrolyte
when electroplating? I calculated that a plating step of 5 um thickness of
gold on 40% of the area of a 100 mm wafer deposits a volume of about 16
mm^3, which corresponds to a weight of 0.3 g (assuming a density of 19.3
g/cm^3, which surely is a too high figure). But how large is the
"practical" consumption of gold in the electrolyte (including deposition on
connectors and other "losses")? Is it about 100%, 150%, 500% of the
actually plated volume/weight? Or can anybody give me a cost figure (pure
electrolyte material costs) of a certain plated volume? (there might be
differences in the electrolyte; just tell me whatever figures you have in
mind). How are you doing such calculations?
I appreciate any estimation.
Best regards,
Joachim