Method of producing aluminate fluorescent material, aluminate fluorescent material and light emitting device

• US 10,392,558 B2
• Filed: 09/14/2017
• Issued: 08/27/2019
• Est. Priority Date: 09/28/2016
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Taketomi, Shozo, Hosokawa, Shoji, Yoshida, Tomokazu, Nishimata, Kazuya
• Primary Examiner(s): Pham, Long
• Application Number:
  US15/704,689
• Publication Number:
  US 20180086975A1
• Time in Patent Office: 712 Days
• Field of Search: None
• CPC Class Codes: C09K 11/643 with alkaline earth metals
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil

Abstract

Provided are a method of producing an aluminate fluorescent material, an aluminate fluorescent material and a light emitting device. The production method includes heat-treating a mixture prepared by mixing a compound containing at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, a Mg-containing compound not acting as a flux, a Mn-containing compound, an Al-containing compound, a first flux containing at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and a Mg-containing second flux to give an aluminate fluorescent material.

Claims

1. An aluminate fluorescent material comprising a composition of an aluminate that comprises at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and Mg and Mn,

and having a ratio (I_B/I_A) of a diffraction intensity I_B of a peak of a plane (0,0,10) at a diffraction angle 2θ

of 39.76°

in an X-ray diffraction pattern measured with a CuKα

ray to a diffraction intensity I_A of a peak of a plane (1,0,7) at a diffraction angle 2θ

of 33.22°

in the X-ray diffraction pattern in a range of 0.4 or more and 10 or less.

2. The aluminate fluorescent material according to claim 1, wherein the content of the at least one alkali metal element is in a range of 20 ppm or more and 3,000 ppm or less.

3. The aluminate fluorescent material according to claim 1, wherein the at least one alkaline earth metal element contains Ba.

4. The aluminate fluorescent material according to claim 1, wherein the at least one alkali metal element contains Na and/or K.

5. The aluminate fluorescent material according to claim 1, having an average particle diameter of 5.0 μ

m or more.

6. A light emitting device comprising the aluminate fluorescent material of claim 1 and an excitation light source having an emission peak wavelength in a range of 380 nm or more and 485 nm or less.

7. An aluminate fluorescent material comprising a composition represented by the following formula (I):

X1_aX2_eMg_bMn_cAl_dO_{a+b+c+1.5d+0.5e} 

 

(I)

wherein X1 represents at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, X2 represents at least one alkali metal element selected from the group consisting of Na, K, Rb and Cs, and a, b, c, d and e satisfy 0.5≤

a≤

1.0, 0.4≤

b≤

0.7, 0.3≤

c≤

0.7, 0.7≤

b+c≤

1.0, 9.0≤

d≤

13.0, 10.0≤

d/a≤

20.0, and 0.0<

e≤

0.1.

8. The aluminate fluorescent material according to claim 7, having an average particle diameter of 5.0 μ

m or more.

9. A light emitting device comprising the aluminate fluorescent material of claim 7 and an excitation light source having an emission peak wavelength in a range of 380 nm or more and 485 nm or less.