Semiconductor device and method for manufacturing the same
A semiconductor device according to embodiments includes a p-type SiC region, a gate insulating film disposed on the p-type SiC region, and a gate electrode disposed on the gate insulating film and including a p-type impurity and 3C—SiC.
1. A semiconductor device, comprising:
a p-type SiC region, the p-type SiC region being 4H—SiC;
a gate electrode including a SiC laver and a metal laver disposed on the SiC layer, the SiC layer including a p-type impurity, 3C—SiC, and 4H—SiC; and
a gate insulating film disposed between the p-type SiC region and the gate electrode.
2. The device according to claim 1 , wherein
the gate electrode includes the p-type impurity and the 3C—SiC at least in a region contacting the gate insulating film.
3. The device according to claim 1 , wherein
the p-type impurity is aluminum (Al), gallium (Ga), or indium (In).
4. The device according to claim 1 , wherein
the 3C—SiC is metalized 3C—SiC.
5. The device according to claim 1 , wherein
a volume of the 3C—SiC in the gate electrode is larger than a volume of the 4H—SiC in the gate electrode.
6. The device according to claim 1 , wherein
a ratio of occupation volume of 3C—SiC among all SiC included in the gate electrode is equal to or more than 90%.
7. The device according to claim 1 , wherein
a concentration of the p-type impurity in the gate electrode is equal to or more than 1×10 20 cm −3 .
8. The device according to claim 1 , wherein
a concentration of a p-type impurity in the p-type SIC region is equal to or less than 1×10 18 cm −3 .
9. The device according to claim 1 , wherein
the gate insulating film is a silicon oxide film.
10. A semiconductor device, comprising:
a p-type SiC region, the p-type SiC region being 4H—SiC;
a gate electrode including a p-type impurity, 3C—SiC, and 4H—SiC; and
a gate insulating film disposed between the p-type SiC region and the gate electrode,
wherein the gate electrode is formed under a temperature of equal to or more than 1,000° C. and equal to or less than 1,200° C.
11. The device according to claim 10 , wherein
the gate electrode is formed by a carbonization of a silicon film.
12. The device according to claim 11 , wherein
the carbonization of the silicon film is performed in an atmosphere including at least one of ethane (C 2 H), ethylene (C 2 H 6 ), or acetylene (C 2 H 2 ).