Patent ID: 8419917

Claim:
A method for operating an electroplating head, comprising: disposing an electroplating head above and proximate to an upper surface of a wafer, the electroplating head including a main chamber, a porous electrically resistive material disposed at an exit of the main chamber, an anode chamber, an anode disposed within the anode chamber, and a membrane disposed to separate the anode chamber from the main chamber, wherein the anode is oriented vertically within the anode chamber to be substantially parallel to the membrane so as to enable natural circulation of an analyte within the anode chamber; transferring cations from the anode through the membrane to an electroplating solution within the main chamber; flowing the electroplating solution through the main chamber and through the porous electrically resistive material at the exit of the main chamber such that the electroplating solution is disposed on the upper surface of the wafer; and establishing an electric current between the anode and the upper surface of the wafer through the electroplating solution, the electric current being uniformly distributed by the porous electrically resistive material present between the anode and the upper surface of the wafer, the electric current causing the cations to be attracted to the upper surface of the wafer.