Method for manufacturing light emitting device and light emitting device

• US 9,190,579 B2
• Filed: 10/25/2013
• Issued: 11/17/2015
• Est. Priority Date: 04/26/2011
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Sato, Takashi, Miyairi, Hiroshi, Watanabe, Kazunori
• Primary Examiner(s): Coleman, William D
• Application Number:
  US14/063,756
• Publication Number:
  US 20140048834A1
• Time in Patent Office: 753 Days
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/48091 Arched
• 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 2924/00014 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 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/54 having a particular shape

Abstract

A method for manufacturing a light emitting device that comprises a light emitting element and a phosphor layer to absorb at least a part of light emitted from the light emitting element to emit a light having a different wavelength from that of the absorbed light comprises a first resin layer forming step of forming a first resin layer with a first resin in which viscosity is adjusted to a first viscosity on a light emitting face of the light emitting element to define a predetermined shape of the phosphor layer; a second resin layer forming step of forming a second resin layer with a second resin containing a phosphor in which viscosity is adjusted to a second viscosity lower than the first viscosity on the first resin layer before curing the first resin layer; and a curing step of curing the first resin layer and the second resin layer.

Claims

1. A method for manufacturing a light emitting device that comprises a light emitting element and a phosphor layer adapted to absorb at least a part of light emitted from the light emitting element and to emit a light having a different wavelength from that of the absorbed light, the method comprising:

a first resin layer forming step of forming a first resin layer on a light emitting face of the light emitting element, the first resin layer comprising a first resin having a first viscosity;

a second resin layer forming step of, before curing the first resin layer, forming a second resin layer on the first resin layer, the second resin layer comprising a second resin containing a phosphor, the second resin having a second viscosity that is lower than the first viscosity; and

a curing step of curing the first resin layer and the second resin layer,

wherein the first resin layer includes a surface that defines a shape of the phosphor layer.

2. The method for manufacturing a light emitting device according to claim 1, further comprising:

a first resin viscosity adjusting step of adjusting the first viscosity of the first resin to not less than 80 Pa·

s nor more than 550 Pa·

s; and

a second resin viscosity adjusting step of adjusting the second viscosity of the second resin to not more than 120 Pa·

s.

3. The method for manufacturing a light emitting device according to claim 1, wherein a surface shape of the first resin layer is defined by a shape of the light emitting element and the first viscosity.

4. The method for manufacturing a light emitting device according to claim 1, wherein the first resin layer is formed by depositing a drop of the first resin on the light emitting face of the light emitting element in the first resin layer forming step.

5. The method for manufacturing a light emitting device according to claim 1, wherein the first resin is formed by depositing a plurality of drops on a plurality of spots on the light emitting face of the light emitting element in the first resin layer forming step.

6. The method according to claim 1 for manufacturing a light emitting device that further includes a protrusion mount for mounting the light emitting element, the second resin layer forming step comprising:

a filler containing resin layer forming step of forming the second resin layer that contains a filler around the mount;

a step of forming the second resin layer that contains the phosphor on the first resin layer and the filler containing resin layer; and

a step of sedimenting the phosphor that is positioned over the filler in preference to the filler.

7. A light emitting device comprising:

a light emitting element; and

a phosphor layer having a phosphor that absorbs at least a part of light emitted from the light emitting element and emits light having a different wavelength from that of the absorbed light,

wherein a resin layer is formed on a light emitting face of the light emitting element such that a peripheral edge of the resin layer substantially conforms to a peripheral edge of the light emitting face and such that an upper surface of the resin layer is a curved surface, and

wherein the phosphor layer is formed along the upper surface of the resin layer such that the light emitting element is separated from any phosphor contained in the light emitting device.

8. The light emitting device according to claim 7, wherein the curved surface is defined based on a shape of the light emitting face of the light emitting element and a surface tension of the resin before curing.

9. The light emitting device according to claim 7, further comprising:

a substrate having a protrusion mount on which the light emitting element is mounted;

a phosphor layer around the mount; and

a filler containing layer provided on the phosphor layer around the mount.

10. The light emitting device according to claim 9, wherein the resin layer and the filler containing layer contain the same resin.

11. A light emitting device comprising:

a light emitting element; and

a phosphor layer adapted to absorb at least a part of light emitted from the light emitting element and emit a light having a different wavelength from that of the absorbed light,

wherein a resin layer is formed on a light emitting face of the light emitting element such that a peripheral edge of the resin layer substantially conforms to a peripheral edge of the light emitting face and such that an upper surface of the resin layer is a curved surface,

wherein the phosphor layer is formed along the upper surface of the resin layer, and

wherein the light emitting device is configured to emit light consisting essentially of light emitted from the light emitting element and the light emitted from the phosphor layer.

12. The light emitting device according to claim 11, wherein the curved surface is defined based on a shape of the light emitting face of the light emitting element and surface tension of the resin before curing.

13. The light emitting device according to claim 11, further comprising:

a substrate having a protrusion mount on which the light emitting element is mounted;

a phosphor layer around the mount; and

a filler containing layer provided on the phosphor layer around the mount.

14. The light emitting device according to claim 11, wherein the resin layer consists essentially of a translucent resin material.

15. The light emitting device according to claim 13, wherein the resin layer and the filler containing layer contain a same resin.