Patent ID: 9136235
Filing Date: 2015-09-15
Classification: H01L

Abstract:
1. A method for forming a package device comprising forming a redistribution layer (RDL) on a first passivation layer and a conductive pad on a substrate, wherein the RDL layer is in contact with the conductive pad through a first opening in the first passivation layer exposing the conductive pad and extends from the conductive pad to a termination point outside a solder ball projection region; forming a second passivation layer on top of the RDL layer and the first passivation layer, the second passivation layer having a second opening to expose a portion of the RDL layer; and forming an under bump metallization (UBM) layer over the second passivation layer and in the second opening to make contact with the exposed portion of the RDL layer, the UBM extending from a second point outside the solder ball projection region to a point within the solder ball projection region; wherein the solder ball projection region is defined as that region determined by projecting an outer periphery of a solder ball onto a surface of the substrate.