Light-emitting element

• US 20120049236A1
• Filed: 06/10/2011
• Published: 03/01/2012
• Est. Priority Date: 08/27/2010
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Kamiya, Masao, Ushida, Yasuhisa, Boyama, Shinya
• Granted Patent: US 8,546,836 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

A light-emitting element includes a semiconductor laminated structure including a nitride semiconductor, and formed by laminating a first semiconductor layer of a first conductivity type, a light-emitting layer and a second semiconductor layer of a second conductivity type different from the first conductivity type, the first semiconductor layer being exposed by removing a part of the second semiconductor layer and the light-emitting layer, a concave portion formed in the exposed portion of the first semiconductor layer, a first electrode formed on the concave portion and being in ohmic contact with the first semiconductor layer, and a second electrode being in ohmic contact with the second semiconductor layer and formed surrounding the first electrode.

Claims

1. A light-emitting element, comprising:

a semiconductor laminated structure comprising a nitride semiconductor, and formed by laminating a first semiconductor layer of a first conductivity type, a light-emitting layer and a second semiconductor layer of a second conductivity type different from the first conductivity type, the first semiconductor layer being exposed by removing a part of the second semiconductor layer and the light-emitting layer;

a concave portion formed in the exposed portion of the first semiconductor layer;

a first electrode formed on the concave portion and being in ohmic contact with the first semiconductor layer; and

a second electrode being in ohmic contact with the second semiconductor layer and formed surrounding the first electrode.

2. The light-emitting element according to claim 1, wherein the concave portion comprises an inclined surface inclined with respect to a depth direction of the semiconductor laminated structure in plan view.

3. The light-emitting element according to claim 2, wherein a plurality of the first electrodes are included and each shaped like a spot in plan view.

4. The light-emitting element according to claim 1, wherein the first semiconductor layer comprises an n-type semiconductor layer and the second semiconductor layer comprises a p-type semiconductor layer, and

wherein the first electrode is an n-side electrode and the second electrode is a p-side electrode.

5. The light-emitting element according to claim 4, wherein the p-side electrode comprises an oxide semiconductor.

6. The light-emitting element according to claim 5, wherein the p-side electrode comprises a p-side contact electrode formed on the p-type semiconductor layer, and a p-side upper electrode formed on the p-side contact electrode.

7. The light-emitting element according to claim 6, wherein the p-side upper electrode and the n-side electrode comprise a same material.

8. The light-emitting element according to claim 7, wherein the p-side upper electrode and the n-side electrode comprise a lower part contacting the n-type semiconductor layer or the p-side contact electrode and comprising Ni or Cr, and an upper part formed on the lower part and comprising Au.