Light emitting device package with a coating layer

• US 10,672,960 B2
• Filed: 10/19/2017
• Issued: 06/02/2020
• Est. Priority Date: 10/19/2017
• Status: Active Grant

• Current Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Original Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Inventors: Li, Shu
• Primary Examiner(s): Muse, Ismail A
• Application Number:
  US15/788,347
• Publication Number:
  US 20190123250A1
• Time in Patent Office: 957 Days
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• 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 2933/005 relating to encapsulations
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective elements
• 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

A light-emitting device is disclosed. The light emitting device includes a base, a reflective layer formed on the base, a coating layer formed on the reflective layer, a sidewall disposed on the base, the sidewall being arranged to form a reflector cup, and a light-emitting diode (LED) chip disposed in the reflector cup.

Claims

1. A light emitting device comprising:

a reflective layer on a base;

a sidewall on the reflective layer defining a reflector cup;

a light emitting diode (LED) within the reflector cup and on the reflective layer;

a transparent coating layer on the reflective layer and at least a portion of the sidewall, the transparent coating layer surrounding at least a portion of the LED;

an opening in the transparent coating layer exposing a portion of the reflective layer; and

a conductive element connecting the LED to the exposed portion of the reflective layer, the conductive element electrically coupling the LED to the base.

2. The light emitting device of claim 1, wherein the LED is bonded to the base via an adhesive layer.

3. The light emitting device of claim 1, wherein:

the sidewall meets the reflective layer at an interface; and

the transparent coating layer has a thickness greater than a thickness of the interface to seal the interface.

4. The light emitting device of claim 1, wherein the transparent coating layer comprises one or more of a Si—

O material, a Si—

O—

N material, an AI—

O material, an Al—

N material, a Si—

N material, and a Ti—

O material.

5. The light emitting device of claim 1, wherein the transparent coating layer has a refractive index in a range of 1.40-1.80.

6. The light emitting device of claim 1, wherein the transparent coating layer has a thickness ranging from 40 nm to 20 μ

m.

11. The light emitting device of claim 2, wherein the transparent coating layer forms a seal around the adhesive layer.

7. A method for manufacturing a light emitting device, comprising:

molding an electrically insulating compound onto a first lead frame and a second lead frame to form a base including a reflector cup, the first lead frame and the second lead frame each including a respective first surface that is plated with a reflective material to form a reflective layer of the base;

depositing an adhesive layer onto the reflective layer;

mounting a light-emitting diode (LED) chip in the reflector cup via the adhesive layer;

forming a transparent coating layer on the reflective layer; and

forming an opening in the transparent coating layer to expose a portion of the reflective layer.

8. The method of claim 7, wherein the forming the transparent coating layer comprises using a liquid deposition to deposit the transparent coating layer on the reflective layer.

9. The method of claim 7, wherein the transparent coating layer is formed of an inorganic material selected from the group consisting of a Si—

O material, a Si—

O—

N material, an AI—

O material, an Al—

N material, a Si—

N material, and a Ti—

O material.

10. The method of claim 7, wherein the transparent coating layer has a refractive index in a range of 1.40-1.80 and a thickness in a range of 40 nm to 20 μ

m.

12. The method of claim 7 further comprising:

connecting the LED chip to the base by a conductive element through the portion of the reflective layer exposed by the opening in the transparent coating layer.