| 摘要 |
An apparatus for electroplating a layer of metal on the surface of a wafer includes a second cathode located remotely with respect to the wafer. The remotely positioned second cathode allows modulation of current density at the wafer surface during an entire electroplating process. The second cathode diverts a portion of current flow from the near-edge region of the wafer and improves the uniformity of plated layers. The remote position of second cathode allows the insulating shields disposed in the plating bath to shape the current profile experienced by the wafer, and therefore act as a“virtual second cathode”. The second cathode may be positioned outside of the plating vessel and separated from it by a membrane.
|
