Methods for use in formation of titanium nitride interconnects

Abstract

A method for use in the fabrication of semiconductor devices includes forming a titanium nitride film and depositing a silicon hard mask over the titanium nitride film. The silicon hard mask is used to pattern a titanium nitride interconnect from the titanium nitride film and the silicon hard mask is also used as a contact etch stop for forming a contact area. In forming the interconnect, the silicon hard mask is dry etched stopping selectively on and exposing portions of the titanium nitride film and the exposed portions of the titanium nitride film are etched resulting in the titanium nitride interconnect. In using the silicon hard mask as a contact etch stop, an insulating layer is deposited over the silicon hard mask and the insulating layer is etched using the silicon hard mask as an etch stop to form the contact area. The silicon hard mask is then converted to a metal silicide contact area. Interconnects formed using the method are also described.