US Patent 7504696 CMOS with dual metal gate

Embodiments herein present a structure and method to make a CMOS with dual metal gates. Specifically, the CMOS comprises a first gate comprising a first metal and a second gate comprising a second metal. The first gate comprises a portion of a first transistor that is complementary to a second transistor that includes the second gate, wherein the first gate and the second gate are situated on the same substrate. Furthermore, the first metal produces a first threshold voltage characteristic, wherein the first metal comprises tantalum. The second metal produces a second threshold voltage characteristic that differs from the first threshold voltage characteristic, wherein the second metal comprises tungsten.