Elongated bumps in integrated circuit devices

摘要

A device includes a substrate, a metal pad over the substrate, and a passivation layer covering edge portions of the metal pad. The passivation layer has a first opening overlapping the metal pad, wherein the first opening has a first lateral dimension measured in a direction parallel to a major surface of the substrate. A polymer layer is over the passivation layer and covering the edge portions of the metal pad. The polymer layer has a second opening overlapping the metal pad. The second opening has a second lateral dimension measured in the direction. The first lateral dimension is greater than the second lateral dimension by more than about 7 μm. A Under-Bump metallurgy (UBM) includes a first portion in the second opening, and a second portion overlying portions of the polymer layer.

主权项

1. A device comprising:
a substrate; a metal pad over the substrate; a passivation layer covering edge portions of the metal pad, wherein the passivation layer comprises a first opening overlapping the metal pad, and wherein the first opening has a first lateral dimension measured in a direction parallel to a major surface of the substrate; a polymer layer over the passivation layer and covering the edge portions of the metal pad, wherein the polymer layer comprises a second opening overlapping the metal pad, wherein the second opening has a second lateral dimension measured in the direction, and wherein the first lateral dimension is greater than the second lateral dimension by more than about 7 μm; a Under-Bump metallurgy (UBM) comprising a first portion in the second opening, and a second portion overlying portions of the polymer layer; and a metal pillar over the UBM, wherein the metal pillar is formed of a non-solder metallic material, and wherein the metal pillar comprises vertical edges substantially perpendicular to a top surface of the metal pad.