Optical semiconductor device

• US 7,808,007 B2
• Filed: 05/29/2008
• Issued: 10/05/2010
• Est. Priority Date: 05/29/2007
• Status: Active Grant

• Current Assignee: Alpad Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Otsuka, Kazuaki, Kuroki, Toshihiro
• Primary Examiner(s): Pert; Evan
• Assistant Examiner(s): Wilson; Scott R
• Application Number:
  US12/128,783
• Publication Number:
  US 20090008666A1
• Time in Patent Office: 859 Days
• Field of Search: 428/690, 428/691, 257/E31.129, 257/E33.061, 257/79, 257/80, 257/81, 257/84, 257/98, 257/99, 257/100, 362/84, 362/800
• US Class Current: 257/80
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/06102 the bonding areas being at different heights
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 2224/16145 the bodies being stacked
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• 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 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil

Abstract

A semiconductor light-emitting element is disposed in a depression of a container. A first fluorescent material layer is located in the depression. At least a portion of the first fluorescent material layer is provided between the opening of the depression and the semiconductor light-emitting element. A second fluorescent material layer having first and second portions is disposed in the depression. The first portion is provided between the bottom of the depression and the semiconductor light-emitting element. The second portion is provided between the side surface of the depression and the semiconductor light-emitting element. The first and second fluorescent material layers are excited by the light radiated from the semiconductor light-emitting element to emit a light having a first wavelength longer than the emission wavelength of the semiconductor light-emitting element and another light having a second wavelength longer than the first wavelength respectively.

Claims

1. An optical semiconductor device comprising:

a container having a depression to reflect light, the depression having an opening, a bottom and a side surface;

a semiconductor light-emitting element placed in the depression to emit light;

a first fluorescent material layer located in the depression, at least a portion of the first fluorescent material layer being provided between the opening of the depression and the semiconductor light-emitting element, and the first fluorescent material layer being excited by the light emitted from the semiconductor light-emitting element to emit light having a first wavelength longer than an light-emission wavelength of the semiconductor light-emitting element; and

a second fluorescent material layer having first and second portions, the first portion being provided between the bottom of the depression and the semiconductor light-emitting element and located in the depression, the second portion provided between the side surface of the depression and the semiconductor light-emitting element and located in the depression, the second fluorescent material layer being excited by the light emitted from the semiconductor light-emitting element to emit light having a second wavelength longer than the first wavelength.

2. The optical semiconductor device according to claim 1, wherein the semiconductor light-emitting element emits blue light, the first fluorescent material layer emits yellow light, and the second fluorescent material layer emits red light.

3. The optical semiconductor device according to claim 1, wherein the first and second portions of the second fluorescent material layer cover surfaces of the semiconductor light-emitting element respectively on the bottom side and on the side surface side of the depression.

4. The optical semiconductor device according to claim 1, wherein a fluorescent material layer is formed on the side surface of the depression to emit light having the second wavelength.

5. The optical semiconductor device according to claim 1, wherein the semiconductor light-emitting element has an inclined side surface, and the second portion of the second fluorescent material layer covers along the inclined side surface.

6. The optical semiconductor device according to claim 5, wherein the second portion of the second fluorescent material layer is bonded to the depression of the container with an adhesive material.

7. The optical semiconductor device according to claim 1, wherein the first fluorescent material layer is formed in the depression so as to bury the semiconductor light-emitting element and the second fluorescent material layer.

8. The optical semiconductor device according to claim 1, wherein the first fluorescent material layer is formed of a resin having a fluorescent material dispersed to emit a fluorescent lights having the first wavelength, and the second fluorescent material layer is formed of a resin having a fluorescent material dispersed to emit a fluorescent light having the second wavelength.

9. An optical semiconductor device comprising:

a container having a depression to reflect light, the depression having an opening, a bottom and a side surface;

a semiconductor light-emitting element placed in the depression to emit light;

a first fluorescent material layer located in the depression, at least a portion of the first fluorescent material layer being provided between the opening of the depression and the semiconductor light-emitting element, and the first fluorescent material layer further being excited by the light emitted from the semiconductor light-emitting element to emit light having a first wavelength longer than a light-emission wavelength of the semiconductor light-emitting element;

a second fluorescent material layer located in the depression and provided between the bottom of the depression and the semiconductor light-emitting element, the second fluorescent material layer being excited by the light emitted from the semiconductor light-emitting element to emit light having a second wavelength longer than the first wavelength; and

a third fluorescent material layer located in the depression and provided between the side surface of the depression and the semiconductor light-emitting element, the third fluorescent material layer being excited by the light emitted from the semiconductor light-emitting element to emit light having the second wavelength longer than the first wavelength.

10. The optical semiconductor device according claim 9, wherein the semiconductor light-emitting element emits blue light, the first fluorescent material layer emits yellow light, and the second and third fluorescent material layers emit red light.

11. The optical semiconductor device according claim 9, wherein the second and third fluorescent material layers are formed apart from each other.

12. The optical semiconductor device according claim 9, wherein the first, second, and third fluorescent material layers are formed of resins having fluorescent materials dispersed respectively.

13. The optical semiconductor device according claim 9, wherein the second fluorescent material layer is formed of a ceramics containing a fluorescent material.

14. The optical semiconductor device according claim 9, wherein the second fluorescent material layer is embedded in another depression provided at the bottom of the depression of the container.

15. The optical semiconductor device according claim 9, further comprising lead terminals, first electrodes and bump electrodes, the lead terminals being provided in association with the container, and the first electrodes being provided on semiconductor layers of the semiconductor light-emitting element to be connected to the lead terminals through the bump electrodes respectively.

16. The optical semiconductor device according claim 9, further comprising lead terminals, first electrodes, a Zener diode and bump electrodes, the lead terminals being provided in association with the container, the first electrodes being provided on semiconductor layers of the semiconductor light-emitting element respectively, and the Zener diode having second electrodes and being provided between the semiconductor light-emitting element and the bottom of the depression of the container,

wherein the first electrodes are connected to the second electrodes of the Zener diode through bump electrodes respectively, the semiconductor light-emitting element and the Zener diode being electrically connected to each other in parallel and in a reverse direction, and the Zener diode is connected to the lead terminals.

17. An optical semiconductor device comprising:

a container having a first depression to reflect light, the first depression having an opening, a bottom and a side surface;

a semiconductor light-emitting element placed in the first depression to emit light, the semiconductor light-emitting element having a substrate, and the substrate having a second depression;

a first fluorescent material layer located in the first depression, at least a portion of the first fluorescent material layer being provided between the opening of the first depression and the semiconductor light-emitting element, and the first fluorescent material layer further being excited by the light emitted from the semiconductor light-emitting element to emit light having a first wavelength longer than an light-emission wavelength of the semiconductor light-emitting element;

a second fluorescent material layer provided in the second depression of the substrate of the semiconductor light-emitting element, the second fluorescent material layer being excited by the light emitted from the semiconductor light-emitting element to emit light having a second wavelength longer than the first wavelength; and

a third fluorescent material layer located in the first depression and provided between the side surface of the first depression and the semiconductor light-emitting element, the third fluorescent material layer being excited by the light emitted from the semiconductor light-emitting element to emit light having the second wavelength longer than the first wavelength.

18. The optical semiconductor device according claim 17, wherein the semiconductor light-emitting element emits blue light, the first fluorescent material layer emits yellow light, and the second and third fluorescent material layers emit red light.

19. The optical semiconductor device according to claim 17, wherein the second fluorescent material layer is bonded to the second depression of the substrate of the semiconductor light-emitting element with an adhesive material.

20. The optical semiconductor device according claim 17, wherein the second and third fluorescent material layers are formed apart from each other.