Method of compensating for material loss in a metal silicone layer in contacts of integrated circuit devices

A method, comprising:

• forming a first cobalt silicide layer on a top surface of a wafer, said first cobalt silicide layer having a thickness;
• forming a dielectric layer above said first cobalt silicide layer;
• selectively removing the dielectric layer to form an opening in said dielectric layer where an electrical contact to a semiconductor functional part is to be formed;
• forming a barrier metal layer consisted of a first and a second metal, said first metal being in contact with said first cobalt silicide layer, said first metal being cobalt having a thickness ranging from approximately 80-100 Å and said second metal being titanium having a thickness of approximately 100 Å;
• annealing the wafer in an inert gas ambient, wherein the second metal of said barrier metal layer is converted into titanium nitride and the first metal being in contact with said first cobalt silicide layer is partly converted into a second cobalt silicide layer;
• and
• forming a plug metal in said opening.

A method, comprising:

• forming a first metal silicide layer comprised of cobalt silicide above a surface of a wafer, said metal silicide layer having a thickness;
• forming a dielectric layer comprised of silicon dioxide above said metal silicide layer;
• selectively removing the dielectric layer to form an opening in said dielectric layer where an electrical contact to a semiconductor functional part is to be formed;
• forming a barrier metal layer consisted of a first and a second metal, said first metal being in contact with said first metal silicide layer, said first metal being cobalt having a thickness ranging from approximately 80-100 Å and said second metal being titanium;
• annealing the wafer in an inert gas ambient, wherein the second metal of said barrier metal is converted into a compound formed of said second metal and the ambient gas and the first metal of said barrier layer is partly converted into a cobalt silicide layer above said first metal silicide layer;
• and
• forming a plug metal comprised of tungsten in said opening.