Phosphor Composition and Method for Producing the Same, and Light-Emitting Device Using the Same

• US 20070259206A1
• Filed: 04/26/2005
• Published: 11/08/2007
• Est. Priority Date: 04/27/2004
• Status: Active Grant

• Current Assignee: Shenzhen Jufei Optoelectronics Co., Ltd.
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Oshio, Shozo
• Granted Patent: US 7,391,060 B2
• Time in Patent Office: Days
• US Class Current: 428/690
• CPC Class Codes: C04B 2235/3213 Strontium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3224 Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
• CPC Class Codes: C04B 2235/3229 Cerium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3852 Nitrides, e.g. oxynitrides, carbonitrides, oxycarbonitrides, lithium nitride, magnesium nitride
• CPC Class Codes: C04B 2235/3865 Aluminium nitrides
• CPC Class Codes: C04B 2235/3873 Silicon nitrides, e.g. silicon carbonitride, silicon oxynitride
• CPC Class Codes: C04B 35/581 based on aluminium nitride
• CPC Class Codes: C04B 35/584 based on silicon nitride
• CPC Class Codes: C04B 35/6265 involving reduction or oxidation
• CPC Class Codes: C04B 35/6268 characterised by the applied pressure or type of atmosphere, e.g. in vacuum, hydrogen or a specific oxygen pressure
• CPC Class Codes: C09K 11/7715 containing cerium
• CPC Class Codes: C09K 11/77218 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• CPC Class Codes: C09K 11/7728 containing europium
• CPC Class Codes: C09K 11/7729 Chalcogenides
• CPC Class Codes: C09K 11/77342 Silicates
• CPC Class Codes: C09K 11/77348 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/056 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 2224/45144 : Gold (Au) as principal constituent
• 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 2224/8592 : Applying permanent coating, e.g. protective coating
• 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 2924/00014 : 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 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/504 : Elements with two or more wavelength conversion materials
• CPC Class Codes: H05B 33/12 : Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: Y02B 20/00 : Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y10S 428/917 : Electroluminescent

Abstract

A light-emitting device is produced using a phosphor composition containing a phosphor host having as a main component a composition represented by a composition formula: aM₃N₂.bAlN.cSi₃N₄, where “M” is at least one element selected from the group consisting of Mg, Ca, Sr, Ba, and Zn, and “a”, “b”, and “c” are numerical values satisfying 0.2≦a/(a+b)≦0.95, 0.05≦b/(b+c)≦0.8, and 0.4≦c/(c+a)≦0.95. This enables a light-emitting device emitting white light and satisfying both a high color rendering property and a high luminous flux to be provided.

Claims

1-45. -45. (canceled)

46. A light-emitting device comprising:

a phosphor layer having a red phosphor and a green phosphor, the red phosphor being activated by Eu²⁺ and having an emission peak in a wavelength range from at least 600 nm to less than 660 nm and the green phosphor being activated only by Eu²⁺ and having an emission peak in a wavelength range from at least 500 nm to less than 560 nm; and

a blue light-emitting element having an emission peak in a wavelength range from at least 440 nm to less than 500 nm;

the red phosphor and the green phosphor emitting light being excited by luminescence of the blue light-emitting element, and

output light of the light-emitting device at least containing a light-emitting component of luminescence from the blue light-emitting element and a light-emitting component of luminescence from the red phosphor and the green phosphor,

wherein

the red phosphor has a composition formula (M_1-xEu_x)AlSiN₃ where M is at least one element selected from the group consisting of Mg, Ca, Sr, Ba, and Zn, and satisfies 0.005≦

x≦

0.3,

the phosphor layer includes substantially no sulfide phosphor, and only the red phosphor includes a nitride phosphor or an oxynitride phosphor, and

the green phosphor is represented by a composition formula (Ba,Sr)₂SiO₄;

Eu²⁺ and its internal quantum efficiency is at least 85% in a wavelength range from at least 440 nm to less than 500 nm.