An apparatus for depositing an electrically conductive layer on the surface of a wafer comprises a flange. The flange has a cylindrical wall and an annulus attached to a first end of the cylindrical wall. The annulus shields the edge region of the wafer surface during electroplating reducing the thickness...http://www.google.de/patents/US6193859?utm_source=gb-gplus-sharePatent US6193859 - Electric potential shaping apparatus for holding a semiconductor wafer during electroplating
