Theory 030/Materials Processing
Plating Uniformity Is a Current Ratio
The claim
Electroplating thickness uniformity is set by the ratio of ohmic to kinetic resistance rather than by current density.
01The mechanism
When ohmic resistance dominates, current crowds at edges; when kinetics dominate, it distributes. The ratio sets which regime applies.
02Predictions
- P1Uniformity should track the ratio.
- P2Higher current density should not fix edge build-up alone.
03Refutation
Uniformity tracking current density would remove the ratio.