Structure with self aligned resist layer on an interconnect surface and method of making same

摘要

A structure is provided with a self-aligned resist layer on a surface of metal interconnects for use in forming air gaps in an insulator material and method of fabricating the same. The non-lithographic method includes applying a resist on a structure which has at least one metal interconnect formed in an insulator material. The method further includes blanket-exposing the resist to energy and developing the resist to expose surfaces of the insulator material while protecting the metal interconnects. The method further includes forming air gaps in the insulator material by an etching process, while the metal interconnects remain protected by the resist.

主权项

1. An intermediate structure, comprising:
a perforated mask layer, wherein the perforated mask layer is positioned over air gaps formed in a substrate, the air gaps being located between metal interconnect structures formed in the substrate, the perforated mask layer being formed adjacent to side edges of a layer of negative tone spin-on organic polymer which is on upper surfaces of the metal interconnect structures, wherein the upper surfaces of the metal interconnect structures are devoid of the perforated mask layer, and wherein upper surfaces of the perforated mask layer are substantially coplanar with the upper surfaces of the metal interconnect structures and a bottom surface of the layer of the negative tone spin-on organic polymer.