Red phosphor, white light emitting device and lighting apparatus

• US 10,002,992 B2
• Filed: 08/02/2016
• Issued: 06/19/2018
• Est. Priority Date: 08/06/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Sung Woo, Yoon, Jung Eun, Yoon, Chul Soo
• Primary Examiner(s): Menz, Laura
• Application Number:
  US15/226,314
• Publication Number:
  US 20170040501A1
• Time in Patent Office: 686 Days
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/77347 Silicon Nitrides or Silicon Oxynitrides
• CPC Class Codes: H01L 2224/48091 Arched
• 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 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 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/501 characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

A red phosphor contains a nitride having a formula of Sr_xMg_ySi_zN_{2/3(x+y+2z+w)}:Eu_w, in which x, y, z, and w satisfy the relationships 0.5≤x≤2, 2.5≤y≤3.5, 0.5≤z≤1.5 and 0<w≤0.1. The red phosphor is configured to emit light having a peak wavelength in a range of from 610 nm to 625 nm when irradiated by an excitation source, and the excitation source may be a blue light source having a dominant wavelength in a range of 420 nm to 470 nm. In such a case, the spectrum of the emitted light has a full-width at half-maximum (FWHM) less than or equal to 55 nm.

Claims

1. A red phosphor comprising a nitride having a formula of Sr_xMg_ySi_zN_{2/3(x+y+2z+w)}:

Eu_w, wherein x, y, z, and w satisfy the relationships 0.95<

x<

1, y is 3, z is 1, 0<

w<

0.05, and x+w=1,

wherein the red phosphor is configured to emit emitted light having a peak wavelength in a range of 610 nm to 625 nm when irradiated by an excitation source, wherein the excitation source is a blue light source having a dominant wavelength in a range of 420 nm to 470 nm, and a spectrum of the emitted light has a full-width at half-maximum (FWHM) less than or equal to 55 nm.

2. The red phosphor of claim 1, wherein the red phosphor has an oxygen content of less than or equal to 1 wt %.

3. The red phosphor of claim 1, wherein an amount of light having a wavelength longer than or equal to 680 nm in a spectrum of the emitted light is less than or equal to 5% of a total amount of the emitted light.