Patent ID: 7622024
Filing Date: 2009-11-24
Classification: C25D,H01L,Y10S

Abstract:
1. An apparatus for electroplating a substantially uniform layer of metal onto a conductive seed layer of a work piece surface having edge regions around a center region, the apparatus comprising: a) a plating chamber; b) a work piece holder for holding the work piece in the plating chamber at a position in alignment with an anode; c) electrical contacts arranged to make electrical connection to the seed layer at one or more locations on the edge regions; and d) an ionically resistive ionically permeable element configured for improving plating uniformity, the element having a porosity of 5% or less, and a thickness of between about 5 and 25 millimeters, wherein the element is positioned to have one surface facing the work piece surface, and located within about 5 millimeters of said work piece surface, when held in plating position by the work piece holder, and an opposite surface facing the anode during plating in the plating chamber, wherein the element does not increase the overall resistance of a plating system by more than 5 Ohms.