Semiconductor light emitting device

Patent metadata

Field	Value
Publication number	US-9368681-B2
Application number	US-201414316485-A
Country	US
Kind code	B2
Filing date	Jun 26, 2014
Priority date	Jul 24, 2001
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

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.

First claim

What is claimed is:

1. A semiconductor light emitting device comprising:
an n-type semiconductor layer, a light emitting layer and a p-type semiconductor layer which are GaN-based semiconductors and formed on a primary surface of a C plane (0001) sapphire substrate, the sapphire substrate comprising a plurality of protrusions formed on the primary surface of the sapphire substrate in a two-dimensionally repeated pattern, and the protrusions having a shape of a polygon in plan view of the light emitting device, said polygon having two adjacent component sides that are perpendicular to A-axis of said GaN-based semiconductors,
wherein in the plan view, an external shape of the semiconductor light emitting device is a polygon having two adjacent component sides that make the same angle as the two adjacent component sides of the protrusions.

2. The semiconductor light emitting device according to claim 1 , wherein a portion of the p-type semiconductor layer is removed to expose a surface of the n-type semiconductor layer so that an n-side electrode is formed on the exposed surface of the n-type semiconductor layer, the exposed surface of the n-type semiconductor layer being located inside the p-type semiconductor layer in the plan view of the light emitting device.

3. The semiconductor light emitting device according to claim 2 , further comprising a p-side pad electrode connected to the p-type semiconductor layer and having a branch electrode that is formed along an outer periphery of the p-type semiconductor layer.

4. The semiconductor light emitting device according to claim 2 , wherein the n-side electrode formed on the exposed surface of the n-type semiconductor layer extends toward vertexes of the external shape of the light emitting device.

5. The semiconductor light emitting device according to claim 2 , wherein the n-type semiconductor layer having the exposed surface comprises Si-doped GaN.

6. The semiconductor light emitting device according to claim 1 , further comprising a mixture of a fluorescent material including YAG and a resin, which is formed on a surface of the semiconductor light emitting device.

Assignees

• Nichia Corp

Inventors

• Niki Isamu
• Yamada Motokazu
• Sano Masahiko
• Shioji Shuji

Classifications

• H10P14/3416

  Nitrides · CPC title

• H10P14/2904 Primary

  Silicon carbide · CPC title

• H10P14/276

  Lateral overgrowth · CPC title

• Y10T428/24479

  including variation in thickness · CPC title

• Y10T428/24355

  Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.] · CPC title