III-V group nitride system semiconductor substrate
View Patent ↗A III-V group nitride system semiconductor substrate is of a III-V group nitride system single crystal. The III-V group nitride system semiconductor substrate has a flat surface, and a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region inside or outside the plane of the substrate.
1. A III-V group nitride system semiconductor substrate, comprising a III-V group nitride system single crystal,
wherein:
a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region outside the substrate; and
the III-V group nitride system semiconductor substrate surface comprises a flat surface.
2. The III-V group nitride system semiconductor substrate according to claim 1 , wherein:
the substrate comprises a self-standing substrate consisting of the III-V group nitride system single crystal.
3. The III-V group nitride system semiconductor substrate according to claim 1 , wherein:
the III-V group nitride system single crystal is of hexagonal system.
4. The III-V group nitride system semiconductor substrate according to claim 1 , wherein:
the III-V group nitride system single crystal is of hexagonal system and the low index surface comprises a C-face.
5. The III-V group nitride system semiconductor substrate according to claim 1 , wherein:
the III-V group nitride system single crystal is of hexagonal system and the low index surface comprises a III-group C-face.
6. The III-V group nitride system semiconductor substrate according to claim 1 , wherein:
the III-V group nitride system single crystal is of hexagonal system and the low index surface comprises an A-face, M-face or R-face.
7. The III-V group nitride system semiconductor substrate according to claim 1 , wherein:
the substrate comprises a surface mirror-finished by polishing.
8. A method of making a III-V group nitride system semiconductor substrate, comprising a III-V group nitride system single crystal, wherein: a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region outside the substrate; and the III-V group nitride system semiconductor substrate surface comprises a flat surface, comprising:
hetero-epitaxially growing the III-V group nitride system single crystal on a hetero-substrate; and
subsequently removing the hetero-substrate to obtain the III-V group nitride system semiconductor substrate.
9. A method of making a III-V group nitride system semiconductor substrate, comprising a III-V group nitride system single crystal, wherein: a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region outside the substrate; and the III-V group nitride system semiconductor substrate comprises a flat surface; comprising:
polishing an upper surface of a substrate, the upper surface being of a III-V group nitride system single crystal and being concave upward-bowed, thereby obtaining the III-V group nitride system semiconductor substrate.
10. A III-V group nitride system semiconductor substrate, comprising:
a first III-V group nitride system semiconductor substrate, comprising a III-V group nitride system single crystal, wherein: a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region outside the substrate; and the first III-V group nitride system semiconductor substrate surface comprises a flat surface; and
a crystal layer that is formed on the first III-V group nitride system semiconductor substrate, and comprises a layer represented by Al x Ga 1-x N (0<x≦1).
11. A III-V group nitride system semiconductor device, comprising:
a III-V group nitride system semiconductor substrate, comprising a III-V group nitride system single crystal, wherein: a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region outside the substrate; and the III-V group nitride system semiconductor substrate surface comprises a flat surface; and
a plurality of crystal layers that are formed on the III-V group nitride system semiconductor substrate, and comprise a layer represented by Al x Ga 1-x N (0<x≦1).
12. A lot of LIT-V group nitride system semiconductor substrate, comprising a plurality of III-V group nitride system semiconductor substrates,
wherein: each of the plurality of III-V group nitride system semiconductor substrates comprises a III-V group nitride system single crystal, wherein: a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region outside the substrate; and the each III-V group nitride system semiconductor substrate surface comprises a flat surface.