To solve a problem wherein, in a semiconductor device where two or more transistors of the same conductivity type each having a high-k film and a metal gate electrode are formed in the same substrate, it is difficult to set the difference between threshold voltages larger than the difference between threshold voltages derived from the difference between impurity concentrations in channel regions.
This semiconductor device includes a first transistor, and a second transistor of the same conductivity type as that of the first transistor. The first transistor includes a first gate insulation film 8a containing a high dielectric material and a first metal, and a first gate electrode 11a. The second transistor includes a second gate insulation film 8b containing a high dielectric material, a first metal and impurities for adjusting a threshold voltage, and a second gate electrode 11b. The first gate insulation film 8a is low in concentration of impurities for adjusting a threshold voltage relative to that of the second gate insulation film 8b, or does not contain the impurities for adjusting a threshold voltage.
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SATO YOSHIHIRO
Hiroshi Takeuchi
Takahisa Shimada
Yuji Takeuchi
Katsumi Imae
Atsushi Fujita
Kazunari Ninomiya
Tomoo Harada
Iseki Katsumori
Seki Kei
Yasuya Sugiura