Method for producing light emitting device

• US 9,614,135 B2
• Filed: 06/01/2016
• Issued: 04/04/2017
• Est. Priority Date: 06/01/2015
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Sato, Yoshiki
• Primary Examiner(s): Lee, Kyoung
• Application Number:
  US15/169,747
• Publication Number:
  US 20160351762A1
• Time in Patent Office: 307 Days
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin

Abstract

A method for producing a light emitting device includes: spraying a resin mixture onto a light emitting element to deposit the resin mixture on the light emitting element, the resin mixture including a thixotropy imparting agent; and curing the resin mixture to form an outermost layer of a light transmissive member and to have an outermost surface having protrusions and recesses on the outermost layer, light emitted from the light emitting element being capable to transmit to an outside of the light emitting device via the light transmissive member.

Claims

1. A method for producing a light emitting device comprising:

spraying a resin mixture onto a light emitting element to deposit the resin mixture on the light emitting element, the resin mixture including a thixotropy imparting agent; and

curing the resin mixture to form an outermost layer of a light transmissive member and to have an outermost surface having protrusions and recesses on the outermost layer, light emitted from the light emitting element being capable to transmit to an outside of the light emitting device via the light transmissive member.

2. The method according to claim 1, wherein the resin mixture comprises a silicone resin, a modified silicone resin, or a hybrid silicone resin.

3. The method according to claim 1, wherein the resin mixture is sprayed onto the light emitting element using a pulse spraying method.

4. The method according to claim 1, wherein an amount of the thixotropy imparting agent in the resin mixture is 1 wt % or more and 30 wt % or less.

5. The method according to claim 1, wherein the outermost layer has a thickness of 3 μ

m or more and 20 μ

m or less.

6. The method according to claim 1, wherein the thixotropy imparting agent comprises silica nano particles.

7. The method according to claim 1, wherein the light transmissive member has a wavelength conversion layer between the light emitting element and the outermost layer, the wavelength conversion layer containing an additional resin and a fluorescent substance.

8. The method according to claim 7, wherein the resin contained in the resin mixture is a same kind as the additional resin of the wavelength conversion layer.

9. The method according to claim 7, wherein the wavelength conversion layer is formed by spraying and depositing the additional resin and the fluorescent substance, and by curing the additional resin.

10. The method according to claim 9, wherein the additional resin and the fluorescent substance are sprayed using a pulse spraying method.

11. The method according to claim 1, wherein the light emitting device comprises

the light transmissive member connected to an upper part of the light emitting element,

a covering member to cover lateral side surfaces of the light emitting element, and

a first external connection terminal and a second external connection terminal which are connected to a lower part of the light emitting element so that at least a lower surface of each of the first and second external connection terminals is exposed outside of the covering member.

12. The method according to claim 1, wherein the protrusions and recesses are formed by particles including the thixotropy imparting agent.

13. The method according to claim 1, wherein the outermost surface has an arithmetic mean roughness of 5 μ

m or more and 30 μ

m or less.

14. The method according to claim 5, wherein the outermost layer has a thickness of 5 μ

m or more and 15 μ

m or less.

15. The method according to claim 4, wherein an amount of the thixotropy imparting agent in the resin mixture is 5 wt % or more and 10 wt % or less.

16. The method according to claim 7, wherein the wavelength conversion layer has a thickness of 30 μ

m or more and 100 μ

m or less.