Patent ID: 7923836
Filing Date: 2011-04-12
Classification: H01L

Abstract:
1. A microelectronic element, comprising: a continuous cheesed metal contact pad having a contact surface and including a plurality of dielectric-filled openings exposed at the contact surface and spaced apart from peripheral boundaries of the contact surface, the dielectric-filled openings surrounded in the plane of the contact surface by the metal of the contact pad, said contact pad having a composition including copper exposed at said contact surface; a passivation layer overlying said major surface of said substrate, said passivation layer exposing at least a portion of said contact surface; and an underbump metallization (“UBM”) including a plurality of metal layers arranged in a stack overlying said contact surface and at least a portion of said passivation layer, said UBM including: a conductive bump including a fusible metal metallurgically bonded to the upper layer of the UBM.