Semiconductor interconnect structure with air gap for reducing intralayer capacitance in metal layers in damascene metalization process

摘要

An interconnect structure capable of reducing intralevel capacitance in a damascene metalization process employs entrapped air gaps between metal lines. The structure comprises at least first and second metal regions separated by a dielectric region, an air gap formed at least partially within the dielectric region, a diffusion barrier positioned over the two metal regions covering a portion of the upper surface of the air gap, and an insulating layer positioned over the diffusion barrier sealing the upper surface of the air gap.