SEMICONDUCTOR LIGHT EMITTING DEVICE AND SEMICONDUCTOR LIGHT EMITTING APPARATUS

• US 20070145385A1
• Filed: 03/13/2007
• Published: 06/28/2007
• Est. Priority Date: 05/17/2004
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Akaike, Yasuhiko, Sugiyama, Hitoshi, Sugawara, Yasuharu, Ohashi, Kenichi
• Granted Patent: US 7,462,869 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers

Abstract

A first semiconductor light emitting device comprises: a transparent substrate; a light emitting layer; and a roughened region. The transparent substrate has a first major surface and a second major surface, and is translucent to light in a first wavelength band. The light emitting layer is selectively provided in a first portion on the first major surface of the transparent substrate and configured to emit light in the first wavelength band. The roughened region is provided in a second portion different from the first portion on the first major surface. A second semiconductor light emitting device comprises: a transparent substrate; a light emitting layer; a first electrode; and at least one groove. The groove is provided on the second major surface of the transparent substrate and is extending from a first side face to a second side face opposing the first side face of the transparent substrate.

Claims

1. A semiconductor light emitting device comprising:

a transparent substrate having a first major surface and a second major surface, and being translucent to light in a first wavelength band;

a light emitting layer selectively provided in a first portion on the first major surface of the transparent substrate and configured to emit light in the first wavelength band; and

a roughened region provided in a second portion different from the first portion on the first major surface.

2. A semiconductor light emitting device according to claim 1, wherein

the first portion includes a center portion on the first major surface and a periphery portion distantly surrounding the center portion, part of the periphery portion being connected to the center portion, and

the second portion is a portion located between the center portion and the periphery portion.

3. A semiconductor light emitting device comprising:

a transparent substrate having a first major surface and a second major surface and being translucent to light in a first wavelength band;

a light emitting layer provided on the first major surface of the transparent substrate and configured to emit light in the first wavelength band;

a first electrode provided on the light emitting layer;

a second electrode provided on the second major surface of the transparent substrate; and

a first groove provided on the second major surface of the transparent substrate and extending from a first side face to a second side face opposing the first side face of the transparent substrate.

4. A semiconductor light emitting device according to claim 3, wherein the first groove has a first beveled surface and a second beveled surface, each beveled surface being oblique with respect to the second major surface.

5. A semiconductor light emitting device according to claim 3, wherein the first groove has a curved surface.

6. A semiconductor light emitting device according to claim 3, wherein at least part of an inner wall of the first groove is provided with one or more roughened regions.

7. A semiconductor light emitting device according to claim 3, wherein a second groove is formed on the second major surface of the transparent substrate, the second groove intersecting with the first groove at a substantially right angle.

8. A semiconductor light emitting device according to claim 3, wherein width of the first groove becomes wider from a center thereof toward the first and second side faces.

9. A semiconductor light emitting device according to claim 3, wherein

the first major surface has a first portion and a second portion,

the light emitting layer is provided on the first portion, and

a roughened region is provided on the second portion.

10. A semiconductor light emitting device according to claim 9, wherein irregularities constituting the roughened region has an average bottom length of 0.1 to 3 micrometers.

11. A semiconductor light emitting device according to claim 9, wherein irregularities constituting the roughened region has an average height of 0.05 to 1.5 micrometers.

12. A semiconductor light emitting device according to claim 3, wherein

the transparent substrate is made of GaP, and

the light emitting layer is made of InGaAlP-based compound semiconductor.

13. A semiconductor light emitting apparatus comprising:

a packaging member having a mounting surface; and

a semiconductor light emitting device having;

a transparent substrate having a first major surface and a second major surface and being translucent to light in a first wavelength band;

a light emitting layer provided on the first major surface of the transparent substrate and configured to emit light in the first wavelength band;

a first electrode provided on the light emitting layer;

a second electrode provided on the second major surface of the transparent substrate; and

at least one groove provided on the second major surface of the transparent substrate and extending from a first side face to a second side face opposing the first side face of the transparent substrate,

the semiconductor light emitting device being mounted on the mounting surface, with the second major surface facing the mounting surface.

14. A semiconductor light emitting apparatus according to claim 13, wherein the packaging member has a light reflecting surface facing the first and second side faces.

15. A semiconductor light emitting apparatus according to claim 13, wherein at least part of an inner wall of the groove is provided with one or more roughened regions.