Nitride semiconductor laminate, semiconductor device, method of manufacturing nitride semiconductor laminate, method of manufacturing nitride semiconductor free-standing substrate and method of manufacturing semiconductor device
A nitride semiconductor laminate includes: a substrate comprising a group III nitride semiconductor and including a surface and a reverse surface, the surface being formed from a nitrogen-polar surface, the reverse surface being formed from a group III element-polar surface and being provided on the reverse side from the surface; a protective layer provided at least on the reverse surface side of the substrate and having higher heat resistance than the reverse surface of the substrate; and a semiconductor layer provided on the surface side of the substrate and comprising a group III nitride semiconductor. The concentration of O in the semiconductor layer is lower than 1×10 17 at/cm 3 .
1. A nitride semiconductor laminate comprising:
a substrate comprising a group III nitride semiconductor and including a surface and a reverse surface, the surface being formed from a nitrogen-polar surface, the reverse surface being formed from a group III element-polar surface, the reverse surface being provided on the reverse side from the surface;
a protective layer provided at least on the reverse surface side of the substrate and having higher heat resistance than the reverse surface of the substrate; and
a semiconductor layer provided on the surface side of the substrate and comprising a group III nitride semiconductor, wherein
concentration of 0 in the semiconductor layer is lower than 1×10 17 at/cm 3 .
2. The nitride semiconductor laminate of claim 1 , wherein
the concentration of 0 in the semiconductor layer is lower than 1×10 16 at/cm 3 .
3. The nitride semiconductor laminate of claim 1 , wherein
the concentration of 0 in the semiconductor layer is lower than 5×10 15 at/cm 3 .
4. The nitride semiconductor laminate of claim 1 , wherein
concentration of C in the semiconductor layer is lower than 1×10 17 at/cm 3 .
5. The nitride semiconductor laminate of claim 4 , wherein
the concentration of C in the semiconductor layer is lower than 1×10 16 at/cm 3 .
6. The nitride semiconductor laminate of claim 4 , wherein
the concentration of C in the semiconductor layer is lower than 5×10 15 at/cm 3 .
7. The nitride semiconductor laminate of claim 1 , wherein
concentration of each of B and Fe in the semiconductor layer is lower than 1×10 15 at/cm 3 .
8. The nitride semiconductor laminate of claim 1 , wherein
the protective layer is also provided on a side of a side surface of the substrate.
9. A semiconductor device comprising:
a substrate comprising a group III nitride semiconductor and including a surface and a reverse surface, the surface being formed from a nitrogen-polar surface, the reverse surface being formed from a group III element-polar surface, the reverse surface being provided on the reverse side from the surface, and
a semiconductor layer provided on the surface side of the substrate and comprising a group III nitride semiconductor, wherein
concentration of 0 in the semiconductor layer is lower than 1×10 17 at/cm 3 .
10. The semiconductor device of claim 9 , wherein
the concentration of 0 in the semiconductor layer is lower than 1×10 16 at/cm 3 .
11. The semiconductor device of claim 9 , wherein
the concentration of 0 in the semiconductor layer is lower than 5×10 15 at/cm 3 .
12. The semiconductor device of claim 9 , wherein
concentration of C in the semiconductor layer is lower than 1×10 17 at/cm 3 .
13. The semiconductor device of claim 12 , wherein
the concentration of C in the semiconductor layer is lower than 1×10 16 at/cm 3 .
14. The semiconductor device of claim 12 , wherein
the concentration of C in the semiconductor layer is lower than 5×10 15 at/cm 3 .
15. The semiconductor device of claim 9 , wherein
concentration of each of B and Fe in the semiconductor layer is lower than 1×10 15 at/cm 3 .
16. The semiconductor device of claim 9 , wherein
the semiconductor layer includes an implantation region in which an impurity is implanted.