Lam Research Corporation
Systems and methods for achieving uniformity across a redistribution layer

Abstract:

Systems and methods for achieving uniformity across a redistribution layer are described. One of the methods includes patterning a photoresist layer over a substrate. The patterning defines a region for a conductive line and a via disposed below the region for the conductive line. The method further includes depositing a conductive material in between the patterned photoresist layer, such that the conductive material fills the via and the region for the conductive line. The depositing causes an overgrowth of conductive material of the conductive line to form a bump of the conductive material over the via. The method also includes planarizing a top surface of the conductive line while maintaining the patterned photoresist layer present over the substrate. The planarizing is facilitated by exerting a horizontal shear force over the conductive line and the bump. The planarizing is performed to flatten the bump.