Patent ID: 8614106
Filing Date: 2013-12-24
Classification: H01L

Abstract:
1. A method for forming a liner-free tungsten contact, the method comprising the steps of: forming a silicide on a conductive region of a semiconductor substrate, the silicide utilizing at least nickel and tungsten, wherein the silicide is formed by depositing a metal layer comprising nickel and tungsten on the conductive region, and performing a thermal annealing process to form the silicide from the metal layer; forming a dielectric layer on the semiconductor substrate and etching an opening through the dielectric layer over the conductive region; depositing a tungsten-containing layer on a sidewall of the opening and on the silicide on the conductive region by exposing the sidewall and the silicide to a non-halogen (fluorine-free) organometallic tungsten precursor and a reducing agent thereby depositing a tungsten-containing film on the silicide and at least a portion of the sidewall, wherein the tungsten-containing layer is formed utilizing fluorine-free materials, wherein the tungsten in the tungsten-containing layer makes up at least five atomic percent (5 at. %) of the tungsten-containing layer and no more than thirty atomic percent (30 at. %) of the tungsten-containing layer; and filling the opening with bulk tungsten to form a contact.