LIGHT EMITTING UNIT AND DISPLAY DEVICE

• US 20120223345A1
• Filed: 02/22/2012
• Published: 09/06/2012
• Est. Priority Date: 03/01/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Tomoda, Katsuhiro, Hirao, Naoki, Biwa, Goshi
• Granted Patent: US 8,686,447 B2
• Time in Patent Office: Days
• US Class Current: 257/89
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 33/44 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 unit including plural kinds of light emitting elements with different light emitting wavelengths, wherein, among the light emitting elements, at least one kind of light emitting element includes a semiconductor layer configured by laminating a first conductive layer, an active layer and a second conductive layer and having a side surface exposed by the first conductive layer, the active layer and the second conductive layer; a first electrode electrically connected to the first conductive layer; a second electrode electrically connected to the second conductive layer; a first insulation layer contacting at least an exposed surface of the active layer in the surface of the semiconductor layer; and a metal layer contacting at least a surface, which is opposite to the exposed surface of the active layer, in the surface of the first insulation layer, and electrically separated from the first electrode and the second electrode.

Claims

1. A light emitting unit comprising plural kinds of light emitting elements with different light emitting wavelengths, wherein, among the plural kinds of light emitting elements, at least one kind of light emitting element includes:

a semiconductor layer configured by laminating a first conductive layer, an active layer and a second conductive layer and having a side surface exposed by the first conductive layer, the active layer and the second conductive layer;

a first electrode electrically connected to the first conductive layer;

a second electrode electrically connected to the second conductive layer;

a first insulation layer contacting at least an exposed surface of the active layer in the surface of the semiconductor layer; and

a metal layer contacting at least a surface, which is opposite to the exposed surface of the active layer, in the surface of the first insulation layer, and electrically separated from the first electrode and the second electrode.

2. The light emitting unit according to claim 1, wherein the first insulation layer and the metal layer cover at least the entire side surface.

3. The light emitting unit according to claim 2, wherein the first insulation layer is formed by CVD (Chemical Vapor Deposition), deposition or sputtering.

4. The light emitting unit according to claim 1,

wherein the first electrode is a metal electrode present at a surface of the first conductive layer and formed to contact a surface of a side opposite to the active layer, and

wherein the first insulation layer and the metal layer are formed from a region opposite to the side surface over a region opposite to the first electrode.

5. The light emitting unit according to claim 4,

wherein a part of the surface of a portion formed in a region of the first insulation layer which is opposite to the first electrode, becomes an exposed surface not covered by the metal layer, and

wherein, among the plural kinds of light emitting elements, the light emitting element including the first insulation layer and the metal layer has a second insulation layer formed from the exposed surface over the surface of the metal layer.

6. The light emitting unit according to claim 5,

wherein the first electrode has an exposed surface not covered by the first insulation layer and the metal layer, and

wherein, among the plural kinds of light emitting elements, the light emitting element including the first insulation layer and the metal layer has a pad electrode formed from the exposed surface of the first electrode over the surface of the first insulation layer and the surface of the second insulation layer.

7. The light emitting unit according to claim 5,

wherein the first electrode has an exposed surface not covered by the first insulation layer and the metal layer, and

wherein, among the plural kinds of light emitting elements, the light emitting element including the first insulation layer and the metal layer has a pad electrode electrically connected to the exposed surface of the first electrode and formed at a region opposite to the first electrode and a region opposite to a part of the metal layer.

8. The light emitting unit according to claim 1,

wherein the plural kinds of light emitting elements include a light emitting element emitting a blue light, a light emitting element emitting a green light and a light emitting element emitting a red light, and

wherein, among these three kinds of light emitting elements, at least the light emitting element emitting a blue color and the light emitting element emitting a green light have the semiconductor layer, the first electrode, the second electrode, the first insulation layer and the metal layer.

9. The light emitting unit according to claim 1, further comprising an insulating body for surrounding each light emitting element by the same member.

10. A display device comprising:

a display panel having a plurality of light emitting units; and

a driving circuit for driving each light emitting unit based on an image signal,

wherein each light emitting unit has plural kinds of light emitting elements with different light emitting wavelengths, and

wherein, among the plural kinds of light emitting elements, at least one kind of light emitting element includes

a semiconductor layer configured by laminating a first conductive layer, an active layer and a second conductive layer and having a side surface exposed by the first conductive layer, the active layer and the second conductive layer;

a first electrode electrically connected to the first conductive layer;

a second electrode electrically connected to the second conductive layer;

a first insulation layer contacting at least an exposed surface of the active layer in the surface of the semiconductor layer; and

a metal layer contacting at least a surface, which is opposite to the exposed surface of the active layer, in the surface of the first insulation layer, and electrically separated from the first electrode and the second electrode.