Patent ID: 7800186
Filing Date: 2010-09-21
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a first metal gate on a first gate insulating film, and a second metal gate on a second insulating film, wherein each of the metal gates includes a metal nitride and a metal carbide, and a work function of each of the metal gates is determined according to ratios of the metal nitride with respect to the metal carbide, wherein the semiconductor device is a CMOS device having a PMOS transistor and an NMOS transistor, the first metal gate being a part of the PMOS transistor and the second metal gate being a part of the NMOS transistor, the metal gates having work functions different from each other, wherein the ratio of metal nitride in the first metal gate of the PMOS transistor is higher than that of the second metal gate of the NMOS transistor, and wherein the ratio of metal nitride in the first metal gate of the PMOS transistor is 85 to 95 at % and the ratio of metal nitride in the second metal gate of the NMOS transistor is 5 to 15 at %.