| 摘要 |
A recessed bond pad within an electronic device on a substrate, and associated method of fabrication. The electronic device includes N contiguous levels of interconnect metallurgy, with level N coupled to the substrate. A first group of metallic etch stops is formed at level M<=N, and a second group of metallic etch stops is formed at level M-1. The second group conductively contacts the first group in an overlapping multilevel matrix pattern. A recessed copper pad is formed at level K<=M-2. A cylindrical space that encloses the metal pad encompasses levels 1,2, . . . , M-1 above the first group, and levels 1,2, . . . , M-2 above the second group. Dielectric material in the cylindrical space is etched away, leaving a void supplanting the etched dielectric material, and leaving exposed surfaces of the cylindrical space. The copper pad is exposed and recessed within the cylindrical space. An aluminum layer is conformally formed to encapsulate the exposed copper pad, to protect the copper pad from oxidation. The recessed bond pad includes the copper pad and the encapsulating aluminum layer. A blanket is formed that covers remaining exposed surfaces of the cylindrical space while leaving a portion of the aluminum layer of the bond pad exposed. The blanket protects the surfaces from oxidation, contaminants, and mechanical stress. The recessing of the bond pad prevents force applied to a wirebond on the bond pad from being transmitted to dielectric material within the substrate.
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