Materials for photoluminescence wavelength converted solid-state light emitting devices and arrangements

• US 9,318,670 B2
• Filed: 08/26/2014
• Issued: 04/19/2016
• Est. Priority Date: 05/21/2014
• Status: Active Grant

• Current Assignee: Intematix Corporation
• Original Assignee: Intematix Corporation
• Inventors: Yuan, Xianglong, Chai, Binghua, Li, Yi-Qun
• Primary Examiner(s): Koslow, Carol M
• Application Number:
  US14/469,523
• Publication Number:
  US 20150340573A1
• Time in Patent Office: 602 Days
• US Class Current: 1/1
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/025 non-luminescent particle coatings or suspension media
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/77348 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

A photoluminescence material paste comprises: a first inorganic photoluminescence material having a first density, a second inorganic photoluminescence material having a second density and a light transmissive non-curable silicone fluid that is not curable by itself. The first density of the first inorganic photoluminescence material is different from the second density of the second inorganic photoluminescence material. The first and second inorganic photoluminescence materials are substantially homogenously distributed within the light transmissive non-curable silicone fluid to form the photoluminescence material paste. A weight loading of the first and second photoluminescence materials in the photoluminescence material paste is in a range of about 60% to about 95%.

Claims

1. A photoluminescence material paste comprising:

a first inorganic photoluminescence material having a first density,

a second inorganic photoluminescence material having a second density, wherein the first density of the first inorganic photoluminescence material is different from the second density of the second inorganic photoluminescence material,

a light transmissive non-curable silicone fluid, wherein the first inorganic photoluminescence material and the second inorganic photoluminescence material are substantially homogenously distributed within the light transmissive silicone fluid to form the photoluminescence material paste,

wherein a weight loading of the first and second photoluminescence materials in the photoluminescence material paste is in a range of about 60% to about 95%, and wherein the non-curable silicone fluid is not curable by itself and is not curable when mixed with another material and wherein the non-curable silicone fluid comprises polyphenylmethylsiloxane.

2. A photoluminescence material paste comprising:

a first inorganic photoluminescence material having a first density,

a second inorganic photoluminescence material having a second density, wherein the first density of the first inorganic photoluminescence material is different from the second density of the second inorganic photoluminescence material,

a light transmissive non-curable silicone fluid, wherein the first inorganic photoluminescence material and the second inorganic photoluminescence material are substantially homogenously distributed within the light transmissive silicone fluid to form the photoluminescence material paste,

wherein a weight loading of the first and second photoluminescence materials in the photoluminescence material paste is in a range of about 60% to about 95%, and

wherein the non-curable silicone fluid is not curable by itself and is curable when mixed with another material.

3. The photoluminescence material paste of claim 2, wherein the non-curable silicone fluid comprises one part of a two-part curable silicone material.

4. The photoluminescence material paste of claim 2, wherein a weight loading of the photoluminescence materials in the photoluminescence material paste is in a range from about 80% to about 90%.

5. The photoluminescence material paste of claim 2, wherein a weight loading of the photoluminescence materials in the photoluminescence material paste is in a range from about 70% to about 80%.

6. The photoluminescence material paste of claim 2, wherein the non-curable silicone fluid has a viscosity of between about 500 and about 100,000 centistokes.

7. The photoluminescence material paste of claim 2, wherein the photoluminescence materials have an average particle size of between about 5 μ

m and about 35 μ

m.

8. The photoluminescence material paste of claim 2, wherein the first photoluminescence material comprises a green light-emitting aluminate-based phosphor material.

9. The photoluminescence material paste of claim 8, wherein the green light-emitting aluminate-based phosphor consists of lutetium, cerium, at least one alkaline earth metal, aluminum, oxygen, and at least one halogen, wherein the phosphor is configured to absorb excitation radiation having a wavelength ranging from about 380 nm to about 480 nm, and to emit light having a peak emission wavelength ranging from about 500 nm to about 550 nm.

10. The photoluminescence material paste of claim 9, wherein the second photoluminescence material comprises a red-emitting nitride-based phosphor.

11. The photoluminescence material paste of claim 10, wherein the red-emitting phosphor comprises a nitride-based composition represented by the chemical formula CaSr_bSi_cAl_dN_eEu_f, wherein:

0.1≦

a≦

0.4;

1.5<

b<

2.5;

4.0≦

c≦

5.0;

0.1≦

d≦

0.15;

7.5<

e<

8.5; and

0<

f<

0.1;

wherein a+b+f>

2+d/2v.

12. The photoluminescence material paste of claim 10, wherein the red-emitting phosphor comprises a nitride-based composition represented by the chemical formula M_(x/v)M′

₂Si_5-xAl_xN₈;

RE, wherein;

M is at least one monovalent, divalent or trivalent metal with valence v;

M′

is at least one of Mg, Ca, Sr, Ba, and Zn; and

RE is at least one of Eu, Ce, Tb, Pr, and Mn;

wherein x satisfies 0.1≦

x<

0.4, and wherein said red-emitting phosphor has the general crystalline structure of M′

₂Si₅N₈;

RE, Al substitutes for Si within said general crystalline structure, and M is located within said general crystalline structure substantially at the interstitial sites.

13. The photoluminescence material paste of claim 2, wherein the photoluminescence materials have an average particle size of between about 15 μ

m and about 20 μ

m.

14. The photoluminescence material paste of claim 2, wherein the non-curable silicone fluid has a viscosity of about 5,000 centistokes.

15. A photoluminescence material paste comprising:

a first inorganic photoluminescence material having a first density,

a second inorganic photoluminescence material having a second density, wherein the first density of the first inorganic photoluminescence material is different from the second density of the second inorganic photoluminescence material,

a light transmissive non-curable silicone fluid, wherein the first inorganic photoluminescence material and the second inorganic photoluminescence material are substantially homogenously distributed within the light transmissive silicone fluid to form the photoluminescence material paste,

wherein the non-curable silicone fluid is not curable by itself, and

wherein a weight loading of the first and second photoluminescence materials in the photoluminescence material paste is in a range of about 60% to about 95% and wherein the first photoluminescence material has a first average particle size and the second photoluminescence material has a second average particle size, wherein the first average particle size is different from the average particle size of the second photoluminescence material.

16. The photoluminescence material paste of claim 15, wherein the non-curable silicone fluid is not curable by itself and is not curable when mixed with another material.

17. The photoluminescence material paste of claim 16, wherein the non-curable silicone fluid comprises polydimethylsiloxane.

21. The photoluminescence material paste of claim 15, wherein the photoluminescence materials have an average particle size of between about 5 μ

m and about 35 μ

m.

22. The photoluminescence material paste of claim 15, wherein the photoluminescence materials have an average particle size of between about 15 μ

m and about 20 μ

m.

23. The photoluminescence material paste of claim 15, wherein the first photoluminescence material comprises a cerium-activated, green-emitting lutetium aluminate phosphor material.

24. The photoluminescence material paste of claim 23, wherein the cerium-activated, green-emitting lutetium aluminate phosphor consists of lutetium, cerium, at least one alkaline earth metal, aluminum, oxygen, and at least one halogen, wherein the phosphor is configured to absorb excitation radiation having a wavelength ranging from about 380 nm to about 480 nm, and to emit light having a peak emission wavelength ranging from about 500 nm to about 550 nm.

25. The photoluminescence material paste of claim 15, wherein the second photoluminescence material comprises a red-emitting nitride-based phosphor.

26. The photoluminescence material paste of claim 25, wherein the red-emitting phosphor comprises a nitride-based composition represented by the chemical formula CaSr_bSiAl_dN_eEu_f, wherein:

0.1≦

a≦

0.4;

1.5<

b<

2.5;

4.0≦

c≦

5.0;

0.1≦

d≦

0.15;

7.5<

e<

8.5; and

0<

f<

0.1;

wherein a+b+f>

2+d/2.

27. The photoluminescence material paste of claim 25, wherein the red-emitting phosphor comprises a nitride-based composition represented by the chemical formula M_(x/v)M′

₂Si_5-xAl_xN₈;

RE, wherein;

M is at least one monovalent, divalent or trivalent metal with valence v;

M′

is at least one of Mg, Ca, Sr, Ba, and Zn; and

RE is at least one of Eu, Ce, Tb, Pr, and Mn;

wherein x satisfies 0.1≦

x<

0.4, and wherein said red-emitting phosphor has the general crystalline structure of M′

₂Si₅N₈;

RE, Al substitutes for Si within said general crystalline structure, and M is located within said general crystalline structure substantially at the interstitial sites.

28. The photoluminescence material paste of claim 15, wherein the non-curable silicone fluid is not curable by itself and is curable when mixed with another material.

29. The photoluminescence material paste of claim 28, wherein the non-curable silicone fluid comprises one part of a two-part curable silicone material.

30. The photoluminescence material paste of claim 15, wherein the first photoluminescence material comprises a green-emitting aluminate phosphor material and the second photoluminescence material comprises a red-emitting nitride-based phosphor.

18. A photoluminescence material paste comprising:

a first inorganic photoluminescence material having a first density,

a second inorganic photoluminescence material having a second density, wherein the first density of the first inorganic photoluminescence material is different from the second density of the second inorganic photoluminescence material,

a light transmissive non-curable silicone fluid, wherein the first inorganic photoluminescence material and the second inorganic photoluminescence material are substantially homogenously distributed within the light transmissive silicone fluid to form the photoluminescence material paste,

wherein the non-curable silicone fluid is not curable by itself, and wherein a weight loading of the first and second photoluminescence materials in the photoluminescence material paste is in a range of about 60% to about 95% and further comprising particles of a light diffusive material having an average particle size of between about 40 nm and about 500 nm.

19. The photoluminescence material paste of claim 18, wherein the particles of light diffusive material have an average particle size of about 60 nm.

20. The photoluminescence material paste of claim 18, wherein the light diffusive material is selected from the group consisting of:

zinc oxide, titanium dioxide, barium sulfate, magnesium oxide, silicon dioxide, aluminum oxide, zirconium dioxide and mixtures thereof.