Cobalt silicide fabrication methods that use protective titanium layers
AssigneeMosel Vitelic, Inc.
InventorsVincent Fortin, Kuei-Chang Tsai
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Abstract
In a cobalt silicide fabrication process, cobalt is formed on a wafer, then titanium is formed over the cobalt, and the wafer is heated to react the cobalt with the silicon. Then the titanium and the unreacted cobalt are removed. The titanium formed by ionized physical vapor deposition to achieve a good step coverage. In some embodiments, the wafer holding pedestal bias is turned off when the titanium is being deposited.
Claims6
A method for forming cobalt silicide on a body which has a surface tha comprises silicon, the method comprising:
- forming a cobalt layer on said surface;
- forming a titanium layer over the cobalt layer by ionized physical vapor deposition;
- reacting the cobalt with the silicon to form cobalt silicide;
- and
- removing the titanium layer, and if any cobalt has not reacted with the silicon then removing the unreacted cobalt;
- wherein the titanium layer is formed by ionized physical vapor deposition.
The method of claim 7 wherein at least part of a sidewall surface of the opening is made of a dielectric.
Dependencies are inferred from the claim text.