Patent ID: 7462556

Claim:
A method for manufacturing a bond pad structure, the method comprising: providing a substrate; forming a metal pad over the substrate; forming a passivation layer over the substrate having an opening to expose a portion of the metal pad; removing an oxidized metal layer on the metal pad using a radio frequency (rf) sputtering etch method; depositing a first PVD thin film comprising chromium at least over the exposed portion of the metal pad; depositing a second PVD thin film comprising copper over the first PVD thin film; depositing a photoresist layer over the substrate; forming a trench in the photoresist layer over at least a portion of the metal pad using a mask; removing photoresist residue in the trench using a plasma descum etch process, while maintaining the first PVD thin film and the second PVD thin film; electroplating a first layer comprising copper in the trench over the second PVD thin film; electroplating a barrier layer comprising nickel in the trench over the first layer; electroplating a termination electrode in the trench over the barrier layer, the termination electrode comprising tin; removing the photoresist layer; etching to remove the second PVD thin film disposed beyond an area; etching to remove the first PVD thin film disposed beyond the area; and reflowing the termination electrode to release stress of the first layer, the terminal electrode being coupled to the barrier layer and atop of the barrier layer, wherein the barrier layer prevents formation of an intermetallic compound in proximity to the first layer by precluding diffusion of tin from the termination electrode to the first layer, and wherein the second PVD thin film has a second thickness at least about twice a first thickness of the first PVD thin film.