Semiconductor light emitting device
AssigneeNichia Corporation
InventorsIsamu Niki, Motokazu Yamada, Masahiko Sano, Shuji Shioji
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Abstract
A semiconductor light emitting device including a substrate, an electrode and a light emitting region is provided. The substrate may have protruding portions formed in a repeating pattern on substantially an entire surface of the substrate while the rest of the surface may be substantially flat. The cross sections of the protruding portions taken along planes orthogonal to the surface of the substrate may be semi-circular in shape. The cross sections of the protruding portions may in alternative be convex in shape. A buffer layer and a GaN layer may be formed on the substrate.
Claims9
A semiconductor light emitting device comprising:
- a C plane (0001) sapphire substrate comprising a plurality of protrusions that are disposed on a surface of the sapphire substrate in a two-dimensionally repeated pattern;
- a plurality of GaN-based semiconductor layers epitaxially grown on the sapphire substrate;
- and
- an ohmic electrode formed on the GaN-based semiconductor layers,
- wherein the semiconductor light emitting device is configured so that light generated in the GaN-based semiconductor layers is emitted from the ohmic electrode or the sapphire substrate,
- the protrusions are configured to scatter or diffract light generated in the semiconductor layers,
- the repeated pattern of the protrusions is such that six protrusions forming a hexagon surround another protrusion,
- in plan view of the sapphire substrate the hexagon has sides that are parallel to A-axis of the sapphire substrate, and
- in plan view of the sapphire substrate the protrusions have a shape of a triangle having sides that are not parallel to A-axis of the GaN-based semiconductor layers.
Dependencies are inferred from the claim text.