Manufacturing method of flip-chip structure of group III semiconductor light emitting device

• US 10,147,849 B2
• Filed: 05/05/2016
• Issued: 12/04/2018
• Est. Priority Date: 05/05/2015
• Status: Active Grant

• Current Assignee: Xiangneng Hualei Optoelectronic Co., Ltd.
• Original Assignee: Xiangneng Hualei Optoelectronic Co., Ltd.
• Inventors: Xu, Shuncheng, Liang, Zhiyong, Cai, Bingjie
• Primary Examiner(s): Peterson, Erik T
• Application Number:
  US15/318,362
• Publication Number:
  US 20170133549A1
• Time in Patent Office: 943 Days
• Field of Search: None
• CPC Class Codes: H01L 27/153 in a repetitive configuration, e.g. LED bars
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• 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

This disclosure refers to a manufacturing method of a flip-chip structure of III group semiconductor light emitting device. The manufacturing method includes steps of: growing a substrate, a buffer layer, an N type nitride semiconductor layer, an active layer and a P type nitride semiconductor layer sequentially from bottom to top to form an epitaxial structure, depositing a transparent conductive layer; defining an isolation groove with the yellow light etching process, depositing a first insulation layer structure, depositing a P type contact metal and N type contact metal, depositing a second insulation layer structure, depositing a flip-chip P type electrode and flip-chip N type electrode, then removing the photo resist by using of the stripping process to get a wafer; thinning, dicing, separating, measuring and sorting the wafer. In this disclosure, structure of the first insulation layer structure which is formed by the Prague reflective layer, the metal layer and the multilayer of oxide insulation, acts as a reflector structure and an insulation layer to replace the flip-chip reflector structure design and the first insulation layer, so that a metal protective layer can be omitted.

Claims

1. A manufacturing method of a flip-chip structure of a group III semiconductor light emitting device, the manufacturing method comprising:

providing a substrate and growing a buffer layer, an n-type nitride semiconductor layer, an active layer and a p-type nitride semiconductor layer on the substrate sequentially from a bottom to a top to form an epitaxial structure, wherein a top surface of the epitaxial structure is a top surface of the p-type nitride semiconductor layer;

depositing a transparent conductive layer on the top surface of the p-type nitride semiconductor layer, defining a pattern of a linear convex mesa, etching the transparent conductive layer, the p-type nitride semiconductor layer and the active layer to expose the n-type nitride semiconductor layer, thereby obtaining the linear convex mesa, wherein the linear convex mesa comprises a first top surface, a side surface and a second top surface, the first top surface and the second top surface individually connects with the side surface to form an L-shaped structure, the first top surface of the linear convex mesa comprising a top surface of the p-type nitride semiconductor layer, the second top surface of the linear convex mesa being a top surface of the n-type nitride semiconductor layer;

defining an isolation groove by etching the n-type nitride semiconductor layer and the buffer layer to expose the substrate;

depositing a first insulation layer structure formed by a Bragg reflective layer, a metal layer and a multilayer of oxide insulation;

wherein the Bragg reflective layer is deposited before the metal layer is deposited, then the metal layer is deposited, and then the multilayer of oxide insulation is deposited, a connection pattern between a p-type contact metal and the transparent conductive layer and a contact pattern between an n-type contact metal and the second top surface of the linear convex mesa are defined, and then a connecting pattern between the multilayer of oxide insulation and the Bragg reflective layer are continuously etched to form the first insulation layer structure;

defining a pattern of the p-type contact metal and a pattern of the n-type contact metal, and then depositing the p-type contact metal and the n-type contact metal, wherein, a bottom surface of the p-type contact metal is located on a surface of the transparent conductive layer and a top surface of the first insulation layer structure, and a bottom surface of the n-type contact metal is located on the second top surface of the linear convex mesa and a top surface of the first insulation layer structure;

depositing a second insulation layer structure, wherein a pattern is defined, the pattern is used for accessing the p-type contact metal and the n-type contact metal with an opening, and then an opening pattern of the second insulation layer structure is etched; and

defining a pattern of a flip-chip p-type electrode and a flip-chip n-type electrode, and depositing the flip-chip p-type electrode and the flip-chip n-type electrode on the second insulation layer structure.

2. The manufacturing method of claim 1, wherein the first insulation layer structure is located on the first top surface, the side surface, the second top surface, the transparent conductive layer and the isolation groove.

3. The manufacturing method of claim 1, wherein the Bragg reflective layer comprises layers of silicon dioxide and titanium dioxide, comprises layers of silicon dioxide and tantalic oxide, or comprises layer of silicon dioxide and niobium oxide.

4. The manufacturing method of claim 3, wherein the thickness of the silicon dioxide is in a range of 30 nm to 1000 nm, the thickness of the titanium dioxide is in a range of 10 nm to 200 nm, the thickness of the tantalic oxide is in a range of 10 nm to 200 nm, and the thickness of the niobium oxide is in a range of 10 nm to 200 nm.

5. The manufacturing method of claim 3, wherein the Bragg reflective layer is a five layer stack of silicon dioxide/titanium dioxide/silicon dioxide/titanium dioxide/silicon dioxide, or a five layer stack of silicon dioxide/tantalic oxide/silicon dioxide/tantalic oxide/silicon dioxide, or a five layer stack of silicon dioxide/niobium oxide/silicon dioxide/niobium oxide/silicon dioxide.

6. The manufacturing method of claim 1, wherein the first insulation layer structure comprises the multilayer of oxide insulation, the metal layer, and the Bragg reflective layer, wherein the multilayer of oxide insulation of the first insulation layer structure is located on the metal layer, and the metal layer is located on a top surface of the Bragg reflective layer.

7. The manufacturing method of claim 6, wherein the metal layer material comprises at least one of silver, aluminum, silver indium, platinum, nickel and titanium, therein a thickness of the silver, the aluminum, the silver indium and the platinum is respectively in a range of 50 nm to 500 nm, and a thickness of the nickel and the titanium is respectively in a range of 0.3 nm to 30 nm.

8. The manufacturing method of claim 6, wherein the multilayer of oxide insulation is formed by at least two of aluminum oxide, silicon dioxide, titanium dioxide, tantalic oxide, niobium oxide, silicon oxide and silicon nitride, a thickness of each layer of the multilayer of oxide insulation is in a range of 30 nm to 200 nm.

9. The manufacturing method of claim 1, wherein the p-type contact metal comprises a p-type linear electrode and a p-type connection metal;

a bottom side of the p-type linear electrode is located on the surface of the first insulation layer structure and the transparent conductive layer;

a bottom side of the p-type connection metal is located on the surface of first insulation layer structure; and

the n-type contact metal comprises an n-type linear electrode and an n-type connection metal, a bottom side of the n-type linear electrode is located on the first insulation layer structure and the second top surface, a bottom side of the n-type connection metal is located on the surface of the first insulation layer structure.

10. The manufacturing method of claim 1, wherein the structure of the p-type contact metal is a multilayer of metal layer, the structure of the n-type contact metal is a multilayer of metal layer, and both the p-type contact metal and the n-type contact metal sequentially comprise a first Ni layer, an Al layer, a second Ni layer, an Au layer and a third Ni layer, or sequentially comprise a Ti layer, an Al layer, the second Ni layer, an Au layer and the third Ni layer, or sequentially comprise the Ti layer, the Al layer and the third Ni layer, or sequentially comprise the first Ni layer, the Al layer, the second Ni layer, a Pt layer, the Au layer and the third layer Ni from inner to outer, or sequentially comprise an Cr layer, the Pt layer, the Au layer and the third Ni layer, or sequentially comprise the first Ni layer, the Al layer and the third Ni layer, or sequentially comprise an Rh layer, therein, a thickness of the Rh layer is in a range of 50 nm to 3000 nm, a thickness of the first Ni layer is in a range of 0.3 nm to 300 nm, a thickness of the Al layer is in a range of 50 nm to 300 nm, a thickness of the second Ni layer is in a range of 10 nm to 300 nm, a thickness of the Pt layer is in a range of 10 nm to 300 nm, a thickness of the Au layer is in a range of 10 nm to 3000 nm, a thickness of the third Ni layer is in a range of 0.3 nm to 300 nm.

11. The manufacturing method of claim 1, wherein the second insulation layer structure is disposed on the top surface of the first insulation layer structure, the top surface of the p-type contact metal, and the top surface of the n-type contact metal.

12. The manufacturing method of claim 11, wherein the second insulation layer structure is a second multilayer of oxide insulation, the second multilayer of oxide insulation is formed by at least two of aluminum oxide, silicon dioxide, titanium dioxide, tantalic oxide, niobium oxide, silicon oxide and silicon nitride, a thickness of each layer of the second multilayer of oxide insulation is in a range of 30 nm to 2000 nm.

13. The manufacturing method of claim 1, wherein the bottom side of the flip-chip p-type electrode is disposed on the surface of the p-type contact metal and the second insulation layer structure, and the bottom side of the flip-chip n-type electrode is disposed on the surface of the n-type contact metal and the second insulation layer structure.

14. The manufacturing method of claim 13, wherein both the flip-chip p-type electrode and the flip-chip n-type electrodes sequentially comprise a Ti layer and a second Ni layer and an Au layer from inner to outer, or sequentially comprise a middle Cr layer, a Pt layer, an Au layer, a second Ni layer, a Pt layer, a second Ni layer and an AuSn layer from inner to outer, or sequentially comprise a first Ni layer and an Al layer, the second Ni layer and the Au layer from inner to outer, or sequentially comprise the middle Cr layer, the Pt layer and the Au layer from inner to outer, or sequentially comprise the first Ni layer, the Al layer, the middle Cr layer and the second Ni layer and the Au layer from inner to outer, or sequentially comprise the first Ni layer, the Al layer, the second Ni layer, the Pt layer and the Au layer from inner to outer, therein a thickness of the first Ni layer is in a range of 0.4 nm to 3 nm, a thickness of the second Ni layer is in a range of 10 nm to 300 nm, a thickness of the Ti layer is in a range of 10 nm to 300 nm, a thickness of the Al layer is in a range of 50 nm to 300 nm, a thickness of the Au layer is in a range of 20 nm to 3000 nm, a thickness of the middle Cr layer is in a range of 10 nm to 300 nm, a thickness of the Pt layer is in a range of 10 nm to 300 nm, and a thickness of the AuSn layer is in a range of 1000 nm to 5000 nm.