Multilevel interconnect structure for integrated circuits

摘要

A multilevel interconnect structure includes a lower conducting layer, a dielectric layer formed on the lower conducting layer, an upper conducting layer formed partly on the dielectric layer, and an I-shaped via plug for electrically connecting the lower conducting layer and the upper conducting layer. The I-shaped via plug has an upper portion which laterally extends into the upper conducting layer, and a lower portion which undercuts the lower conducting layer.