Semiconductor device and method for manufacturing the same
A semiconductor device of an embodiment includes a SiC layer having a surface, the surface inclined at an angle of 0° to 10° with respect to a {000-1} face or the surface having a normal line direction inclined at an angle of 80° to 90° with respect to a <000-1> direction, a gate electrode, a gate insulating layer provided between the surface and the gate electrode, and a region provided between the surface and the gate insulating layer, a maximum concentration of deuterium (D) in the region being 1×10 20 cm −3 or more and a maximum concentration of hydrogen (H) in the region being 1×10 19 cm −3 or less.
1. A semiconductor device comprising:
a SiC layer having a surface, the surface inclined at an angle of 0° to 10° with respect to a {000-1} face or the surface, having a normal line direction inclined at an angle of 80° to 90° with respect to a <000-1> direction;
a gate electrode;
a gate insulating layer provided between the surface and the gate electrode; and
a region provided between the surface and the gate insulating layer, a maximum concentration of deuterium (D) in the region being 1×10 20 cm −3 or more and a maximum concentration of hydrogen (H) in the region being 1×10 19 cm −3 or less.
2. The device according to claim 1 , wherein concentration distribution of deuterium in the region has a peak, and a full width at half maximum of the peak is 10 nm or less.
3. The device according to claim 1 , wherein the maximum concentration of deuterium in the region is 1×10 21 cm −3 or more.
4. The device according to claim 1 , wherein the gate insulating layer is a silicon oxide film.
5. A method for manufacturing a semiconductor device comprising:
forming a gate insulating layer on a surface of a SiC layer, the surface inclined at an angle of 0° to 10° with respect to a {000-1} face, or, the surface having a normal line direction inclined at an angle of 80° to 90° with respect to a <000-1> direction;
performing first heat treatment in an atmosphere containing deuterium after forming the gate insulating layer; and
forming a gate electrode on the gate insulating layer after performing the first heat treatment.
6. The method according to claim 5 , wherein the gate insulating layer is a silicon oxide film.
7. The method according to claim 5 , further comprising performing second heat treatment of 800° C. or more after the first heat treatment.
8. The method according to claim 5 , wherein the gate insulating layer is a deposition film.
9. The method according to claim 5 , wherein the gate insulating layer is a thermal oxide film.
10. The method according to claim 5 , wherein the first heat treatment is performed at 900° C.
11. A method for manufacturing a semiconductor device comprising:
forming a gate insulating layer on a surface of a SiC layer, the forming the gate insulating layer including thermally-oxidizing the surface in an atmosphere containing deuterium and oxygen, the surface inclined at an angle of 0° to 10° with respect to a {000-1}face, or the surface having a normal line direction inclined at an angle of 80° to 90° with respect to a <000-1> direction; and
forming a gate electrode on the gate insulating layer.
12. The method according to claim 11 , wherein the gate insulating layer is formed by depositing an insulating film after the thermally-oxidizing the surface.
13. The method according to claim 12 , wherein the insulating film is a silicon oxide film.
14. The method according to claim 11 , further comprising performing a heat treatment of 800° C. or more after the forming the gate insulating layer.
15. The method according to claim 11 , wherein the thermally-oxidizing the surface is performed at 800° C. or more.
16. The method according to claim 11 , comprising bonding deuterium (D) in the region to carbon at the surface.
17. The device according to claim 1 , wherein deuterium (D) in the region is bonded to carbon at the surface.
18. The method according to claim 5 , comprising bonding deuterium (D) in the region to carbon at the surface.