Semiconductor device and method for manufacturing the same
View Patent ↗A semiconductor device including a first transistor of a first conductivity type provided on a first active region of a semiconductor region, and a second transistor of a second conductivity type provided on a second active region of the semiconductor region. The first transistor includes a first gate insulating film and a first gate electrode, the first gate insulating film contains a high-k material and a first metal, and the first gate electrode includes a lower conductive film, a first conductive film and a first silicon film. The second transistor includes a second gate insulating film and a second gate electrode, the second gate insulating film contains a high-k material and a second metal, and the second gate electrode includes a second conductive film made of the same material as the first conductive film, and a second silicon film.
1. A semiconductor device comprising:
a first transistor of a first conductivity type provided on a first active region of a semiconductor region; and
a second transistor of a second conductivity type provided on a second active region of the semiconductor region, wherein the second active region is separated from the first active region by a device isolation region, wherein
the first transistor includes
a first gate insulating film formed on the first active region and containing a high-k material and a first metal, and
a first gate electrode including a lower conductive film formed on the first gate insulating film, a first conductive film formed on the lower conductive film, and a first silicon film formed on the first conductive film,
the second transistor includes
a second gate insulating film formed on the second active region and containing the high-k material and a second metal, and
a second gate electrode including a second conductive film formed on the second gate insulating film and made of the same material as the first conductive film, and a second silicon film formed on the second conductive film.
2. The semiconductor device of claim 1 , wherein
the first gate insulating film does not contain the second metal, and
the second gate insulating film does not contain the first metal.
3. The semiconductor device of claim 1 , wherein
a value of an effective work function of the first transistor is altered by the first metal, and
a value of an effective work function of the second transistor is altered by the second metal.
4. The semiconductor device of claim 1 , wherein
a thickness of the first gate electrode is greater than that of the second gate electrode.
5. The semiconductor device of claim 1 , wherein
the lower conductive film contains a conductive material and the second metal.
6. The semiconductor device of claim 5 , wherein
the conductive material is tantalum nitride, titanium nitride, or tantalum carbide.
7. The semiconductor device of claim 1 , wherein
the first conductive film and the second conductive film are each made of titanium nitride, ruthenium or aluminum nitride-molybdenum.
8. The semiconductor device of claim 1 , wherein
the first transistor is an N-type MIS transistor, and
the second transistor is a P-type MIS transistor.
9. The semiconductor device of claim 8 , wherein
the first metal is at least one of a lanthanoid element, scandium, strontium and magnesium, and
the second metal is at least one of aluminum and tantalum.
10. The semiconductor device of claim 1 , wherein
the first transistor is a P-type MIS transistor, and
the second transistor is an N-type MIS transistor.
11. The semiconductor device of claim 10 , wherein
the first metal is at least one of aluminum and tantalum, and
the second metal is at least one of a lanthanoid element, scandium, strontium and magnesium.
12. The semiconductor device of claim 1 , wherein
the high-k material is an oxide, an oxynitride or a silicate containing at least one of hafnium, zirconium and yttrium.
13. The semiconductor device of claim 1 , wherein
the first gate insulating film includes a first base film made of a silicon oxynitride between the first active region and the high-k material in the first gate insulating film, and
the second gate insulating film includes a second base film made of the silicon oxynitride between the second active region and the high-k material in the second gate insulating film.