Structure and process for W contacts

摘要

Structures and processes include a single metallization step for forming a metal nitride liner layer suitable for contact formation. The structure and processes generally includes forming a nitrogen-enriched surface in a deposited metal liner layer or forming a nitrogen-enriched surface in the dielectric material prior to deposition of the metal liner layer. In this manner, nitridization of the metal occurs upon deposition of nitrogen ions into the metal liner layer and/or as a function of additional conventional processing in fabricating the integrated circuit such that the deposited nitrogen ions diffuse into at least a portion of the metal liner layer. As a consequence, only a single metal layer deposition step is needed to form the metal liner layer.

主权项

1. A method for forming an integrated circuit comprising:
providing a patterned substrate comprising a contact hole in a dielectric layer, wherein the contact hole includes sidewalls formed of the dielectric layer and a bottom surface defined by a source or drain region or a metal gate; conformally depositing a single metal liner layer onto the patterned substrate; generating nitrogen ions from a nitrogen containing gas selected from the group consisting of nitrogen (N2) and ammonia (NH3); exposing the single metal liner layer to form a nitrogen enriched metal liner layer; and depositing a tungsten metal into the contact hole, wherein the tungsten metal is in direct contact with the nitrogen enriched metal liner layer.