Method of manufacturing light emitting device

• US 10,050,182 B2
• Filed: 12/21/2017
• Issued: 08/14/2018
• Est. Priority Date: 12/08/2015
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Tada, Takaaki, Wakaki, Takayoshi
• Primary Examiner(s): Gebreyesus, Yosef
• Application Number:
  US15/851,459
• Publication Number:
  US 20180114882A1
• Time in Patent Office: 236 Days
• CPC Class Codes: H01L 2224/49111 the connectors connecting two common bonding areas, e.g. Litz or braid wires
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 2924/19107 off-chip wires
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 33/005 Processes
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A light emitting device includes: a light emitting element including: a semiconductor structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, each containing a nitride semiconductor, a p-electrode disposed on a portion of a surface of the p-type semiconductor layer on a side opposite to a surface provided with the active layer, and an n-electrode disposed on a surface of the n-type semiconductor layer on a side opposite to a surface provided with the active layer in a region other than a region facing the p-electrode; and a protective film continuously covering a surface of the n-electrode and a surface of the n-type semiconductor layer. The protective film includes a first metal oxide film and a second metal oxide film that are alternately layered, the first metal oxide film containing a first metal, and the second metal oxide film containing a second metal.

Claims

1. A light emitting device comprising:

a light emitting element including;

a semiconductor structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, in this order, each containing a nitride semiconductor,

a p-electrode disposed on a portion of a surface of the p-type semiconductor layer on a side opposite to a surface provided with the active layer, and

an n-electrode disposed on a surface of the n-type semiconductor layer on a side opposite to a surface provided with the active layer in a region other than a region facing the p-electrode,

wherein the light emitting element has a peak wavelength of 410 nm or less; and

a protective film continuously covering a surface of the n-electrode and a surface of the n-type semiconductor layer,

wherein the protective film includes a first metal oxide film and a second metal oxide film that are alternately layered, the first metal oxide film containing a first metal, and the second metal oxide film containing a second metal,

wherein the first metal oxide film includes one or more individual first metal oxide film layers, and

the second metal oxide film includes one or more individual second metal oxide film layers.

2. The light emitting device according to claim 1, wherein:

the protective film has a structure in which the same number of single first metal oxide films and single second metal oxide films are deposited.

3. The light emitting device according to claim 1, wherein:

the thickness of the first metal oxide film is the same as the thickness of the second metal oxide film.

4. The light emitting device according to claim 1, wherein:

the light emitting device further comprises a base including a p-side electrode layer and an n-side electrode layer,

the p-electrode is connected to the p-side electrode layer,

the n-electrode is connected to the n-side electrode layer via a wire, and

the protective layer continuously covers a surface of the wire, a surface of the n-electrode, and a surface of the n-type semiconductor layer.

5. The light emitting device according to claim 4, wherein:

the light emitting device further comprises a cover,

the base includes a recess, and

the cover is fixed to the base so as to close an opening of the recess of the base.

6. The light emitting device according to claim 5, wherein:

a light-transmissive resin is not arranged between the light emitting element and the cover.

7. The light emitting device according to claim 6, wherein:

the recess of the base includes a first bottom surface at a central portion of the recess and a second bottom surface surrounding the first bottom surface, a height of the second bottom surface being different from a height of the first bottom surface, and

the p-side electrode layer is disposed on the first bottom surface of the recess, and the n-side electrode layer is disposed on the second bottom surface of the recess.

8. The light emitting device according to claim 5, wherein:

the cover is made of an inorganic material.

9. The light emitting device according to claim 8, wherein:

the cover is made of the borosilicate glass, quartz glass, or sapphire glass.

10. The light emitting device according to claim 4, wherein:

the light emitting device further comprises a support substrate and a p-side connection electrode being disposed on the lower surface of the support substrate,

the support substrate served to support the semiconductor structure, and

the p-electrode of the light emitting element and the p-side electrode layer of the base is connected via the p-side connection electrode.

11. The light emitting device according to claim 10, wherein:

the support substrate is made of Si or Cu—

W.

12. The light emitting device according to claim 1, wherein:

the p-electrode has a larger area than the area of the entire n-electrode.

13. The light emitting device according to claim 1, wherein:

the first metal is selected from the group consisting of Al, Nb, Ti and Si, and

the second metal is selected from the group consisting of Al, Nb, Ti, and Si and being different from the first metal.

14. The light emitting device according to claim 13, wherein:

one of the first metal and second metal is made of Al, and

the other of the first metal and second metal is made of Si.

15. The light emitting device according to claim 1, wherein:

the n-electrode includes a plurality of n-side connection electrode portions disposed in parallel to the straight line of the n-type semiconductor layer as viewed from above and extended portions extend from each of the n-side connection electrode portions.

16. The light emitting device according to claim 1, wherein:

the light emitting device further comprises a Zener diode.