Semiconductor device and its manufacturing method
A semiconductor device, which can use silicon-germanium for a source/drain extension of pMOS, form a silicide layer on the source/drain, and realize a high-speed operation, is provided by comprising a gate electrode formed in a first conductive type region of a semiconductor substrate via an insulator, a first sidewall formed on a side face of the gate electrode, a second sidewall formed on a side face of the first sidewall, a semiconductor layer formed below the second sidewall, including a first impurity layer of a second conductive type and containing germanium, a second impurity layer formed in a region outside the second sidewall and containing impurities of the second conductive type with a higher concentration than those in the first impurity layer, and a silicide layer formed on the second impurity layer.
1. A semiconductor device comprising:
a gate electrode formed in a first conductive type region of a silicon semiconductor substrate via an insulator;
a first sidewall formed on a side face of the gate electrode;
a second sidewall formed on a side face of the first sidewall;
a semiconductor layer formed below the second sidewall, including a first impurity layer of a second conductive type and containing germanium, and having substantially the same width as that of the second sidewall;
a second impurity layer formed in a region outside the second sidewall and containing impurities of the second conductive type with a higher concentration than those in the first impurity layer; and
a silicide layer formed on the second impurity layer.
2. The semiconductor device according to claim 1 ,
wherein a surface of the semiconductor layer is positioned at a higher level than that of a surface of the semiconductor substrate.
3. The semiconductor device according to claim 2 ,
wherein a surface of the second impurity layer is positioned in a different level from the surface of the semiconductor substrate.
4. The semiconductor device according to claim 1 ,
wherein a germanium concentration in the second impurity layer is equal to or less than 10%.
5. The semiconductor device according to claim 1 ,
wherein the semiconductor layer contains silicon germanium.
6. The semiconductor device according to claim 1 ,
wherein the first conductive type is n-type and the second conductive type is p-type.
7. The semiconductor device according to claim 1 ,
wherein the second impurity layer has a lower germanium concentration than the semiconductor layer.
8. The semiconductor device according to claim 7 ,
wherein a surface of the semiconductor layer is positioned at a higher level than that of a surface of the semiconductor substrate.
9. The semiconductor device according to claim 8 ,
wherein a surface of the second impurity layer is positioned in a different level from the surface of the semiconductor substrate.
10. The semiconductor device according to claim 7 ,
wherein a germanium concentration in the second impurity layer is equal to or less than 10%.
11. The semiconductor device according to claim 7 ,
wherein the semiconductor layer contains silicon germanium.
12. The semiconductor device according to claim 1 ,
wherein the second sidewall has a width greater than the first sidewall.
13. The semiconductor device according to claim 1 ,
wherein a surface of the semiconductor layer is positioned at a higher level than that of a surface of the semiconductor substrate, a germanium concentration in the second impurity layer is equal to or less than 10%, wherein the semiconductor layer contains silicon germanium, and the first conductive type is n-type and the second conductive type is p-type.
14. A semiconductor device comprising first and second semiconductor elements, wherein:
the first semiconductor element comprising:
a first gate electrode formed in a first conductive type region of a silicon semiconductor substrate via an insulator;
a first sidewall formed on a side face of the first gate electrode;
a second sidewall formed on a side face of the first sidewall;
a semiconductor layer formed below the second sidewall, including a first impurity layer of a second conductive type and containing germanium, and having substantially the same width as that of the second sidewall;
a second impurity layer formed in a region outside the second sidewall and containing impurities of the second conductive type with a higher concentration than those in the first impurity layer; and
a first silicide layer formed on the second impurity layer; and
the second semiconductor element comprising:
a second gate electrode formed in a second conductive type region of the semiconductor substrate via an insulator;
a third sidewall formed on a side face of the second gate electrode;
a fourth sidewall formed on a side face of the third sidewall;
a third impurity layer of a first conductive type formed in the semiconductor substrate below the sidewall of the fourth sidewall;
a fourth impurity layer formed in a region outside the fourth sidewall and containing impurities of a first conductive type with a higher concentration than those in the third impurity layer; and
a second silicide layer formed on the fourth impurity layer.
15. The semiconductor device according to claim 14 ,
wherein a surface of the semiconductor layer is positioned at a higher level than that of a surface of the semiconductor substrate.
16. The semiconductor device according to claim 14 ,
wherein a germanium concentration in the second impurity layer is equal to or less than 10%.
17. The semiconductor device according to claim 14 ,
wherein the semiconductor layer contains silicon germanium.
18. The semiconductor device according to claim 14 ,
wherein the first conductive type is n-type and the second conductive type is p-type.
19. The semiconductor device according to claim 14 ,
wherein the second impurity layer has a lower germanium concentration than the semiconductor layer.
20. The semiconductor device according to claim 19 ,
wherein a surface of the semiconductor layer is positioned at a higher level than that of a surface of the semiconductor substrate.
21. The semiconductor device according to claim 19 ,
wherein a germanium concentration in the second impurity layer is equal to or less than 10%.
22. The semiconductor device according to claim 19 ,
wherein the semiconductor layer contains silicon germanium.
23. The semiconductor device according to claim 14 ,
wherein the second sidewall has a width greater than the first sidewall.
24. The semiconductor device according to claim 14 ,
wherein a surface of the semiconductor layer is positioned at a higher level than that of a surface of the semiconductor substrate, a germanium concentration in the second impurity layer is equal to or less than 10%, wherein the semiconductor layer contains silicon germanium, and the first conductive type is n-type and the second conductive type is p-type.