US Patent 11894241 Heterogeneous bonding structure and method forming same

A method includes forming a first package component, which formation process includes forming a first plurality of openings in a first dielectric layer, depositing a first metallic material into the first plurality of openings, performing a planarization process on the first metallic material and the first dielectric layer to form a plurality of metal pads in the first dielectric layer, and selectively depositing a second metallic material on the plurality of metal pads to form a plurality of bond pads. The first plurality of bond pads comprise the plurality of metal pads and corresponding parts of the second metallic material. The first package component is bonded to a second package component.