Metal Gate Stack Having TaAlCN Layer

A method comprising:

• forming a gate structure over a semiconductor substrate;
• forming an interlayer dielectric layer surrounding the gate stack;
• at least partially removing the gate stack, thereby forming an opening;
• and
• forming a multi-function blocking/wetting layer in the opening, a work function layer over the multi-function blocking/wetting layer, and a conductive layer over the work function layer, wherein the multi-function blocking/wetting layer, the work function layer, and the conductive layer fill the opening, and further wherein the multi-function blocking/wetting layer comprises titanium aluminum carbon nitride (TiAlCN).

A method comprising:

• forming a gate stack over a semiconductor substrate;
• forming an interlayer dielectric layer surrounding the gate stack;
• at least partially removing the gate stack, thereby forming an opening;
• and
• forming a multi-function blocking/wetting layer in the opening, a work function layer over the multi-function blocking/wetting layer, and a conductive layer over the work function layer, wherein the multi-function blocking/wetting layer, the work function layer, and the conductive layer fill the opening, and further wherein the multi-function blocking/wetting layer includes a first tantalum aluminum carbon nitride (TaAlCN) layer.