Verfahren zur Herstellung eines elektrischer Kontaktes über einem Silizium-Halbleiterplättchen

摘要

A process is described for forming planar tungsten-filled contacts to a silicon substrate (10) in contact openings (24) through an insulating layer (20) which provides for the formation of titanium silicide (32) in and on the silicon surface at the bottom of the contact openings (24) to provide low resistance silicide interconnections between the silicon substrate (10) and the tungsten (40). A titanium nitride layer (34,36,38) is formed over the titanium silicide (34) and on the surfaces of the insulation layer, including the top surface of the insulation layer (20) and the sidewall surfaces of the contact openings (24) through the insulating layer (20). This titanium nitride layer provides a nucleation layer which permits a good bond to form from the tungsten through the titanium nitride and titanium silicide in the contact openings to the silicon substrate; and from the tungsten through the titanium nitride layer to the insulator material such as silicon dioxide (SO2), resulting in the formation of low resistance and low defect density contacts.