Phosphor, manufacturing method thereof, and light-emitting device using the phosphor

Patent metadata

Field	Value
Publication number	US-10519368-B2
Application number	US-201615175627-A
Country	US
Kind code	B2
Filing date	Jun 7, 2016
Priority date	Dec 9, 2013
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

A red-light emitting phosphor is provided, having a basic composition represented by Ka(Si1-x,Mnx)Fb and also having a particular Raman spectrum, wherein the intensity ratio I1/I0, which is a ratio of (I1) the peak in a Raman shift of 600±10 cm−1 assigned to Mn—F bonds in the crystal to that (I0) in a Raman shift of 650±10 cm−1 assigned to Si—F bonds in the crystal, is 0.09 to 0.22. This phosphor is produced by bringing a silicon source in contact with an aqueous reaction solution containing potassium permanganate and hydrogen fluoride, wherein a molar ratio of hydrogen fluoride to potassium permanganate is 87 to 127.

First claim

The invention claimed is:

1. A phosphor represented by the following formula (I):
K a (Si 1-x ,Mn x )F b ;
wherein a, b and x are numbers satisfying the conditions of 1.5≤a≤2.5, 5.5≤b≤6.5, and 0<x≤0.06 respectively;
wherein the phosphor has a Raman spectrum in which an intensity ratio (I 1 /I 0 ), which is a ratio of the peak intensity (I 1 ) in a Raman shift of 600±10 cm −1 assigned to Mn—F bonds in the crystal to that (I 0 ) in a Raman shift of 650±10 cm −1 assigned to Si—F bonds in the crystal, is 0.09 to 0.17;
wherein the phosphor has an absorptivity (α) in a range of 66% to 83.9%; and
wherein the absorptivity (α) is equal to an external quantum efficiency (η) of the phosphor/an internal quantum efficiency (η′) of the phosphor, wherein the internal quantum efficiency (η′) of the phosphor is represented by formula (II) below, and wherein the external quantum efficiency (η) of the phosphor is represented by formula (III) below,

internal
⁢

⁢
quantum
⁢

⁢

efficiency
(

η
′

)

=

∫

λ
·

[

P
⁡

(
λ
)

]

⁢
d
⁢

⁢
λ

∫

λ
·

[

E
⁡

(
λ
)

-

R
⁡

(
λ
)

]

⁢
d
⁢

⁢
λ

(
II
)

external
⁢

⁢
quantum
⁢

⁢

efficiency
(
η
)

=

∫

λ
·

[

P
⁡

(
λ
)

]

⁢
d
⁢

⁢
λ

∫

λ
·

[

E
⁡

(
λ
)

]

⁢
d
⁢

⁢
λ

(
III
)

wherein E(λ) represents a whole spectrum of light emitted by an excitation light source onto the phosphor in terms of the number of photons,
wherein R(λ) represents a spectrum of light emitted by the excitation light source but reflected by the phosphor in terms of the number of photons, and
wherein P(λ) represents an emission spectrum of the phosphor in terms of the number of photons.

2. The phosphor according to claim 1 , having an internal quantum efficiency of 80% or more.

3. The phosphor according to claim 1 , wherein the external quantum efficiency is in a range of 61% to 73%.

4. The phosphor according to claim 1 , wherein the internal quantum efficiency of the phosphor is 85% or more.

5. The phosphor according to claim 1 , wherein the internal quantum efficiency of the phosphor is in a range of 85% to 92%.

Assignees

• Toshiba Kk
• Toshiba Materials Co Ltd

Inventors

• Hiramatsu Ryosuke
• Tamura Jun
• Ishida Kunio
• Albessard Keiko
• Kato Masahiro

Classifications

• C09K11/617 Primary

  Silicates · CPC title

• C09K11/57

  containing manganese or rhenium · CPC title

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W72/5363

  the connected ends being wedge-shaped · CPC title