Vertical light emitting devices with nickel silicide bonding and methods of manufacturing

• US 9,842,976 B2
• Filed: 09/01/2016
• Issued: 12/12/2017
• Est. Priority Date: 03/22/2011
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Bernhardt, Michael J.
• Primary Examiner(s): Fan, Michele
• Application Number:
  US15/254,483
• Publication Number:
  US 20160372649A1
• Time in Patent Office: 467 Days
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• 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

Various embodiments of light emitting devices, assemblies, and methods of manufacturing are described herein. In one embodiment, a method for manufacturing a lighting emitting device includes forming a light emitting structure, and depositing a barrier material, a mirror material, and a bonding material on the light emitting structure in series. The bonding material contains nickel (Ni). The method also includes placing the light emitting structure onto a silicon substrate with the bonding material in contact with the silicon substrate and annealing the light emitting structure and the silicon substrate. As a result, a nickel silicide (NiSi) material is formed at an interface between the silicon substrate and the bonding material to mechanically couple the light emitting structure to the silicon substrate.

Claims

1. A light emitting die, comprising:

a light emitting structure;

a silicon substrate spaced apart from the light emitting structure;

a bonding stack between the light emitting structure and the silicon substrate, the bonding stack mechanically coupling the light emitting structure to the silicon substrate,

wherein the bonding stack includes;

a barrier material on the light emitting structure;

a bonding material spaced apart from the barrier material, the bonding material containing nickel (Ni) and being the outermost layer of the bonding stack,

a mirror material directly between the barrier material and the bonding material; and

a nickel silicide (NiSi) material at an interface between the silicon substrate and the bonding material.

2. The light emitting die of claim 1 wherein:

the barrier material contains nickel (Ni); and

the mirror material contains silver (Ag).

3. The light emitting die of claim 1 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

the bonding stack consists essentially of the barrier material, the bonding material, the mirror material, and the nickel silicide material.

4. The light emitting die of claim 1 wherein:

the light emitting die further includes a conductive material between the light emitting structure and the bonding stack, the conductive material containing at least one of indium tin oxide, aluminum zinc oxide, and fluorine-doped tin oxide;

the silicon substrate includes a P-type silicon substrate;

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

the bonding stack consists essentially of the barrier material, the bonding material, the mirror material, and the nickel silicide material.

5. The light emitting die of claim 1 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

the bonding material has a thickness of about 30 Angstroms.

6. The light emitting die of claim 1 wherein:

the bonding stack includes a first bonding portion and a second bonding portion;

the first bonding portion is on a surface of the light emitting structure; and

the second bonding portion is on a sidewall of the light emitting structure.

7. The light emitting die of claim 1 wherein:

the bonding stack includes a first bonding portion and a second bonding portion;

the first bonding portion is on a surface of the light emitting structure;

the second bonding portion is on a sidewall of the light emitting structure; and

the light emitting die further includes a passivation material on the sidewall of the light emitting structure, the passivation material abutting the second bonding portion.

8. The device of claim 1 wherein the nickel silicide material is formed by at least partially and only consuming the bonding material and silicon substrate.

9. A method for manufacturing a lighting emitting device, comprising:

forming a light emitting structure on a growth substrate material;

depositing a barrier material, a mirror material, and a bonding material on the light emitting structure, the bonding material containing nickel (Ni);

placing the light emitting structure onto a silicon carrier substrate such that the bonding material directly contacts the silicon carrier substrate; and

bonding the light emitting structure and the silicon carrier substrate via forming a nickel silicide (NiSi) material at an interface between the silicon carrier substrate and the bonding material.

10. The method of claim 9 wherein bonding the light emitting structure and the silicon carrier substrate includes annealing the light emitting structure and the silicon substrate.

11. The method of claim 10 wherein:

forming the light emitting structure includes forming N-type gallium nitride (GaN), GaN/indium gallium nitride (InGaN) multiple quantum wells, and P-type GaN on the growth substrate material in sequence and subsequently removing the growth substrate material from the N-type GaN;

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

annealing the light emitting structure and the silicon carrier substrate includes;

heating the light emitting structure and the silicon carrier substrate to a temperature from about 300°

C. to about 450°

C.; and

maintaining the temperature for a heating period of about 1 to 30 minutes under a bonding pressure of about 50 mPa to about 100 mPa.

12. The method of claim 10 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

annealing the light emitting structure and the silicon carrier substrate includes forming the nickel silicide (NiSi) material at the interface between the silicon carrier substrate and the bonding material without completely consuming the bonding material.

13. The method of claim 10 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

annealing the light emitting structure and the silicon carrier substrate includes forming the nickel silicide (NiSi) material at the interface between the silicon carrier substrate and the bonding material without completely consuming the nickel (Ni) contained in the bonding material.

14. The method of claim 10 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

annealing the light emitting structure and the silicon carrier substrate includes;

maintaining a thickness of the bonding material greater than about 30 Angstroms after forming the nickel silicide (NiSi) material.

15. The method of claim 10 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag); and

annealing the light emitting structure and the silicon carrier substrate includes;

reacting a portion of the nickel (Ni) contained in the bonding material with the silicon (Si) contained in the silicon carrier substrate to form the nickel silicide (NiSi) material; and

bonding the silicon carrier substrate to the light emitting structure with the formed nickel silicide (NiSi) material.

16. The method of claim 9 wherein:

the barrier material contains nickel (Ni); and

the mirror material contains silver (Ag).

17. A method for manufacturing a lighting emitting device, comprising:

depositing a barrier material, a mirror material, and a bonding material on a light emitting structure, the bonding material containing nickel (Ni);

contacting the deposited bonding material with a carrier containing silicon (Si);

directly reacting the nickel (Ni) in the bonding material with the silicon (Si) in the carrier at a bonding temperature, under a bonding pressure, and for a bonding period; and

adjusting at least one of the bonding temperature, the bonding period, and the bonding pressure based on a target thickness of the bonding material remaining after the reaction.

18. The method of claim 17 wherein the thickness of the bonding material remaining after the reaction is greater than about 30 Angstroms.

19. The method of claim 17, wherein the bonding material remaining after the reaction acts as a barrier material.

20. The method of claim 17 wherein reacting the nickel (Ni) in the bonding material with the silicon (Si) in the carrier includes forming nickel silicide (NiSi) at an interface between the carrier and the bonding material remaining after the reaction.

21. The method of claim 17 wherein:

the barrier material contains nickel (Ni);

the mirror material contains silver (Ag);

the target thickness of the bonding material remaining after the reaction is greater than about 30 Angstroms;

the light emitting structure includes a first semiconductor material, an active region, and a second semiconductor material;

sequentially depositing the barrier material, the mirror material, and the bonding material includes depositing the barrier material on the second semiconductor material, depositing the mirror material on the barrier material, and depositing the bonding material on the mirror material;

reacting the nickel (Ni) in the bonding material with the silicon (Si) in the carrier includes forming nickel silicide (NiSi) at an interface between the carrier and the bonding material remaining after the reaction;

the method further includes;

preventing the mirror material from diffusing into the carrier with the bonding material remaining after the reaction; and

preventing the mirror material from diffusing into the second semiconductor material with the barrier material.

22. A method of manufacturing a plurality of light emitting devices, comprising:

forming a plurality of light emitting dies on a growth substrate via epitaxial growth;

depositing a barrier material, a mirror material, and a bonding material over the growth substrate in series, the bonding material containing nickel (Ni);

attaching the growth substrate to a carrier material containing silicon (Si) such that the bonding material directly contacts a surface of the carrier material;

forming nickel silicide (NiSi) at an interface between the carrier and the bonding material, thereby mechanically coupling the plurality of light emitting dies to the carrier material; and

singulating the plurality of light emitting dies mechanically coupled to the carrier material to form a plurality of light emitting devices.

23. The method of claim 22 wherein forming the plurality of light emitting devices includes:

sequentially depositing N-type gallium nitride (GaN), GaN/indium gallium nitride (InGaN) multiple quantum wells, and P-type GaN on the growth substrate;

forming a plurality of openings in the deposited N-type GaN, GaN/InGaN multiple quantum wells, and P-type GaN, the individual openings separating two adjacent light emitting dies; and

depositing a passivation material into the individual openings, the passivation material being in contact with at least the N-type GaN and the GaN/InGaN multiple quantum wells.

24. The method of claim 22 wherein forming the plurality of light emitting devices includes:

sequentially depositing N-type gallium nitride (GaN), GaN/indium gallium nitride (InGaN) multiple quantum wells, and P-type GaN on the substrate;

forming a plurality of openings in the deposited N-type GaN, GaN/InGaN multiple quantum wells, and P-type GaN, the individual openings separating two adjacent light emitting dies; and

singulating the plurality of light emitting dies includes singulating the plurality of light emitting dies along the openings in the deposited N-type GaN, GaN/InGaN multiple quantum wells, and P-type GaN.

25. The method of claim 22 wherein the deposited barrier material, mirror material, and bonding material are generally planar.

26. A method of manufacturing a plurality of light emitting devices, comprising:

forming a plurality of light emitting dies on a substrate via epitaxial growth by;

sequentially depositing N-type gallium nitride (GaN), GaN/indium gallium nitride (InGaN) multiple quantum wells, and P-type GaN on the substrate;

forming a plurality of openings in the deposited N-type GaN, GaN/InGaN multiple quantum wells, and P-type GaN, the individual openings separating two adjacent light emitting dies; and

depositing a passivation material into the individual openings, the passivation material being in contact with at least the N-type GaN and the GaN/InGaN multiple quantum wells;

depositing a barrier material, a mirror material, and a bonding material on the substrate in series, the bonding material containing nickel (Ni), wherein the deposited barrier material, mirror material, and bonding material each include a first portion on the P-type GaN and a second portion in the openings;

contacting the bonding layer with a carrier, wherein the bonding material is in direct contact with a surface of the carrier, the carrier containing silicon (Si);

forming nickel silicide (NiSi) at an interface between the carrier and the bonding material by at least partially consuming the carrier and the bonding material, thereby mechanically coupling the plurality of light emitting dies to the carrier; and

singulating the plurality of light emitting dies mechanically coupled to the carrier to form a plurality of light emitting devices.

27. The method of claim 26 wherein the second portion of the deposited barrier material abuts the passivation material in the openings.