Semiconductor Light Emitting Device

• US 20070278502A1
• Filed: 09/12/2005
• Published: 12/06/2007
• Est. Priority Date: 09/13/2004
• Status: Abandoned Application

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Shakuda, Yukio, Nishida, Toshio, Sonobe, Masayuki
• Application Number:
  US11/662,542
• Publication Number:
  US 20070278502A1
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: C09K 11/584 with zinc or cadmium
• CPC Class Codes: C09K 11/642 with zinc or cadmium
• CPC Class Codes: C09K 11/7701 Chalogenides
• CPC Class Codes: H01L 2224/24 of an individual high density interconnect connector
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• 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 2924/12044 OLED
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

There is provided a semiconductor light emitting device which can prevent flickering in illumination due to an alternative current drive, and sensing incongruity at a time of turning off a switch, by providing anti-flickering means in itself, when it is assembled in an illumination device without any extra parts therein. A plurality of light emitting units (1) are formed, by forming a semiconductor lamination portion (17) by laminating semiconductor layers on a substrate (11) so as to form a light emitting layer, by electrically separating the semiconductor lamination portion (17) into a plurality of units, and by providing a pair of electrodes (19) and (20). The light emitting units (1) are respectively connected in series and/or parallel with a wiring film (3). A fluorescent layer (6) containing a fluorescent material having an afterglow time of 10 msec or more and 1 sec or less and/or a layer containing a phosphorescent glass material are formed at a light emitting surface side of the plurality of light emitting units (1).

Claims

1. A semiconductor light emitting device comprising:

a substrate;

a semiconductor lamination portion formed on the substrate by laminating semiconductor layers so as to form a light emitting layer;

a plurality of light emitting units formed by separating the semiconductor lamination portion electrically into a plurality of units, each of the plurality of light emitting units having a pair of electrodes;

wiring films which are connected to the electrodes for connecting each of the plurality of light emitting units in series and/or parallel; and

a fluorescent layer containing a fluorescent material having an afterglow time of 10 msec or more and 1 sec or less, the fluorescent layer being provided at a light emitting surface side of the plurality of light emitting units.

2. The semiconductor light emitting device according to claim 1, wherein the fluorescent material is at least one member selected from a group comprising ZnS doped with Cu, Y₂O₃ and ZnS doped with Al.

3. The semiconductor light emitting device according to claim 1, wherein a layer containing a phosphorescent glass material is provided on a surface of the fluorescent layer.

6. The semiconductor light emitting device according to claim 1, wherein the semiconductor lamination portion is made of nitride semiconductor, and white light is emitted by being provided with a light color conversion member which converts a wavelength of light emitted in the light emitting layer to white light, and with at least one of a fluorescent material having an afterglow time of 10 msec or more and 1 sec or less and a phosphorescent material having an afterglow time of 1 sec or more, at least at a light emitting surface side of the semiconductor lamination portion.

7. The semiconductor light emitting device according to claim 6, wherein the semiconductor lamination portion is formed on a light transmitting substrate, a back surface of which is the light emitting surface side, and the light color conversion member and at least one of the fluorescent material and the phosphorescent material are provided on the back surface of the substrate.

8. The semiconductor light emitting device according to claim 1, further comprising:

a resin layer coating a semiconductor chip having the plurality of light emitting units,

wherein the resin layer is mixed with at least one of a fluorescent material having an afterglow time of 10 msec or more and 1 sec or less and a phosphorescent material having an afterglow time of 1 sec or more.

9. The semiconductor light emitting device according to claim 1, further comprising:

a resin layer coating a semiconductor chip having the plurality of light emitting units, and

a layer containing at least one of a fluorescent material having an afterglow time of 10 msec or more and 1 sec or less and a phosphorescent material having an afterglow time of 1 sec or more provided on the resin layer.

10. The semiconductor light emitting device according to claim 8, wherein the semiconductor lamination portion is made of nitride semiconductor and white light is emitted by mixing a light color conversion member converting a wavelength of light emitted in the light emitting layer to white light in the resin layer.

4. A semiconductor light emitting device comprising:

a substrate;

a semiconductor lamination portion formed on the substrate by laminating semiconductor layers so as to form a light emitting layer;

a plurality of light emitting units formed by separating the semiconductor lamination portion electrically into a plurality of units, each of the plurality of light emitting units having a pair of electrodes;

wiring films which are connected to the electrodes for connecting each of the plurality of light emitting units in series and/or parallel; and

a layer containing a phosphorescent glass material, the layer being provided at a light emitting surface side of the plurality of light emitting units.

5. The semiconductor light emitting device according to claim 4, wherein the phosphorescent glass material is a glass material mixed with terbium.