Anisotropic material damage process for etching low-K dielectric materials

摘要

In one example, a method includes forming a mask layer above or in a dielectric material. The dielectric material is exposed to photon radiation in an ambient atmosphere comprising a carbon gettering agent to generate damaged portions of the dielectric material. The mask layer blocks the photon radiation. The damaged portions of the dielectric material are removed.

主权项

1. A method, comprising:
forming a plurality of conductive lines disposed in a first dielectric material, wherein said conductive lines comprise a conductive fill material and a liner layer disposed between at least a bottom surface of said conductive fill material and said first dielectric material; exposing said first dielectric material to photon radiation in an ambient atmosphere comprising a carbon gettering agent to generate damaged portions of said first dielectric material, wherein said conductive lines block said photon radiation, and said damaged portions have a depth greater than a depth of a bottom surface of said liner layer of said conductive lines; removing said damaged portions of said first dielectric material to define recesses between said conductive lines, said recesses having a depth greater than said depth of said bottom surface of said liner layer of said conductive lines; forming a cap layer above said conductive lines without filling said recesses to define an air gap between said conductive lines; and forming a second dielectric material above said cap layer.