Semiconductor light-emitting device

• US 7,042,012 B2
• Filed: 04/18/2003
• Issued: 05/09/2006
• Est. Priority Date: 05/27/2002
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Shibata, Naoki, Ito, Jun, Inoue, Mitsuhiro, Senda, Masanobu, Hayashi, Toshimasa, Nishijima, Kazuki
• Primary Examiner(s): Nguyen, Cuong
• Application Number:
  US10/515,655
• Publication Number:
  US 20050247949A1
• Time in Patent Office: 1,117 Days
• Field of Search: 257 79-103
• US Class Current: 257/79
• CPC Class Codes: H01L 33/145 with a current-blocking structure
• CPC Class Codes: H01L 33/40 Materials therefor
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

An insulation film 150 made of SiO₂ is formed on a p-type layer 106, and a multiple thick film positive electrode 120, which is a metal film formed through metal deposition, is formed on the insulation film 150 and on the p-type layer 106 at the central portion of which has a window and is exposed. The insulation film 150 has a thickness of one fourth multiple of emission wavelength. Thickness of the insulation film 150 is generally determined by multiplying one fourth of intramedium emission wavelength by an odd number. By interference effect, directivity of radiated light along the optical axis direction can be improved.

Claims

1. A light-emitting semiconductor device which emits lights from a substrate side, comprising:

an emission layer;

a metal film which reflects lights; and

a transparent insulation film which is sandwiched between a non-emission part of said emission layer and said metal film,

wherein said metal film supplies electric current only to said emission part of the emission layer, and an interval of said emission layer and the metal film is determined by multiplying by an odd number one fourth of an intramedium emission wavelength in the interval.

2. A light-emitting semiconductor device according to claim 1, wherein said insulation film is made of an oxygen compound or a nitrogen compound.

3. A light-emitting semiconductor device according to claim 2, wherein said insulation film comprises at least one selected from SiO₂ and TiO₂ and said nitride compound comprises at least one selected from AlN and SiN.

4. A light-emitting semiconductor device according to claim 1, wherein said light-emitting semiconductor device comprises a light-emitting device of Group III nitride compound semiconductor.

5. A light-emitting semiconductor device according to claim 1, wherein said light-emitting semiconductor device is connected to a plastic fiber.

6. A light-emitting semiconductor device according to claim 2, wherein said light-emitting semiconductor device comprises a light-emitting device of Group III nitride compound semiconductor.

7. A light-emitting semiconductor device according to claim 3, wherein said light-emitting semiconductor device comprises a light-emitting device of Group III nitride compound semiconductor.

8. A light-emitting semiconductor device according to claim 2, wherein said light-emitting semiconductor device is connected to a plastic fiber.

9. A light-emitting semiconductor device according to claim 3, wherein said light-emitting semiconductor device is connected to a plastic fiber.

10. A light-emitting semiconductor device according to claim 4, wherein said light-emitting semiconductor device is connected to a plastic fiber.