Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
  • C09K11/7728—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing europium
  • C09K11/7734—Aluminates
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/0883—Arsenides; Nitrides; Phosphides
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/64—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing aluminium
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
  • C09K11/7728—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing europium
  • C09K11/77348—Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
  • F21V9/00—Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters
  • F21V9/30—Elements containing photoluminescent material distinct from or spaced from the light source
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
  • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
  • H10H20/80—Constructional details
  • H10H20/81—Bodies
  • H10H20/822—Materials of the light-emitting regions
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10H—INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
  • H10H20/00—Individual inorganic light-emitting semiconductor devices having potential barriers, e.g. light-emitting diodes [LED]
  • H10H20/80—Constructional details
  • H10H20/85—Packages
  • H10H20/851—Wavelength conversion means
  • H10H20/8511—Wavelength conversion means characterised by their material, e.g. binder
  • H10H20/8512—Wavelength conversion materials
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
  • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Definitions

• the present invention is directed to novel luminescent materials for light emitting devices, especially to the field of novel luminescent materials for LEDs.
• Phosphors comprising silicates, phosphates (for example, apatite) and aluminates as host materials, with transition metals or rare earth metals added as activating materials to the host materials, are widely known.
• phosphates for example, apatite
• aluminates as host materials, with transition metals or rare earth metals added as activating materials to the host materials.
• transition metals or rare earth metals added as activating materials to the host materials
• LEDs may be built which show improved lighting features, especially thermal stability.
• the photostability of the material is greatly enhanced in contrast with materials having a smaller particle size
• the material has a higher emission than comparable materials.
• this invention also relates to the use of calcium in siliconitridic materials for increasing the average particle size.
• the Barium content is somewhat around 20% to 60% mol percent. This has been found to be advantageous for many applications due to the improved luminescence properties of the resulting material.
• the material comprises oxygen. Surprisingly this has been found to greatly increase the photostability of the material for many applications within the present invention. Without being bound to any theory, it is believed that small amounts of S1N 4 tetrahedra containing Si bridging N atoms are removed from the M 2 S1 5 N 8 lattice and the resulting charge is compensated by terminal O atoms. However, in most applications it has been found that the oxygen content should not be too high, i.e. b should not exceed 0.2.
• less than 10% of the phosphor particles show an average diameter ⁇ 2 ⁇ . This has been found
• the ratio of the longest and shortest particle edge length is ⁇ 5. This has been found advantageous since by doing so for most applications the industrial applicability can be easened.
• the present invention relates to the use of calcium in siliconitridic materials for increasing the average particle size. This goes especially for materials of the type M 2 Si5-a-bAl a N8- a -4bO a +4b (with 0 ⁇ a ⁇ 2 and 0 ⁇ b ⁇ 2), which are insofar preferred embodiments of the present invention.
• inventive use of calcium differs from the known use of flux materials, some of which are known to also enhance particle size. According to the invention, calcium is essentially evenly distributed in the powder whereas flux materials are usually not part of the luminescnet material except for impurities.
• the material has the structure M 2 Si5-a-bAl a N8- a -4bO a +4b, with M being a divalent metal ion and with 0 ⁇ a ⁇ 2 and 0 ⁇ b ⁇ 2.
• the material has the structure according to the present invention.
• the present invention furthermore relates to a light emitting structure, especially a LED, comprising at least one material according to the present invention.
• the present invention furthermore relates to as system comprising a material according to the present invention and/or materials made according to the inventive methods shown above, being used in one or more of the following applications:
• Fig. 1 shows a scanning electron image of a material according to Example I of the present invention
• Fig. 2 shows a scanning electron image of a material according to Example
• Fig. 3 shows a scanning electron image of a material according to a
• comparative Example Fig. 4 shows a diagramm of emission power vs. layer thickness for for two pcLED comprising an inventive and a comparative material, respectively;
• Fig. 5 shows a diagramm of emission vs. wavelength for two pcLEDs
• Fig. 6 shows a plot of the total emitted power as a function of the CIE x color coordinate for the two pcLEDs of Fig. 5 EXPERIMENTAL SECTION
• Figs 1 to 3 show scanned electron images of the powders of Inventive
• Example I inventive Example II and the comparative Example (no calcium), respectively.
• Fig. 4 shows the total emitted power of the pcLEDs (red phosphor layers on a blue LED, 444nm peak emission) vs. the layer thickness both for the material of Inventive Example III
• Fig. 5 shows two emission spectra of red phosphor layers on a blue LED (444nm peak emission) of layers out of the material according to Inventive Example III ("A", solid line) as well as the comparative Example II ("B", dashed line) having identical blue transmission.
• the pcLED using the material according to the invention delivers approx. 6% percent additional light.
• Fig. 6 shows a plot of the total emitted power as a function of the CIE x color coordinate for the two pcLEDs of Fig. 5 ("A" and "B" have the same meaning as in Fig. 5).
• the CIE-color coordinate serves as a measure of the ratio of red to blue light in the LED emission spectrum. From the figure it can clearly be seen that the efficiency advantage of the inventive material increases with increasing conversion of light.
• the average diameter can be measured by the following procedure based on light scattering (see XU, R. Particle Characterization: Light Scattering Methods, Kluwer
• the powder to be measured is suspended in a liquid media such as demineralized water with a dispersant added to stabilize the suspenion.
• a liquid media such as demineralized water with a dispersant added to stabilize the suspenion.
• the particle suspension is then analyzed by laser diffraction to obtain information about particle size distribution through measurements of scattering intensity as a function of the scattering angle and the wavelength and polarization of light based on applicable scattering models.
• Such a method is absolute in nature without the need to calibrate instrument.
• particle sizes can be directly measured with a microscope (optical microscope, scanning electron microscope) and particle size distributions can be calculated based on image processing procedures.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Inorganic Chemistry (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• General Engineering & Computer Science (AREA)
• Luminescent Compositions (AREA)
• Led Device Packages (AREA)

Priority Applications (7)

Applications Claiming Priority (2)

Publications (1)

Family

ID=45350440

Family Applications (1)

Country Status (9)

Cited By (12)

Families Citing this family (10)

Citations (6)

Family Cites Families (30)

• 2011
  • 2011-11-28 RU RU2013129842/05A patent/RU2591943C2/ru active
  • 2011-11-28 WO PCT/IB2011/055329 patent/WO2012073177A1/en not_active Ceased
  • 2011-11-28 JP JP2013541455A patent/JP5970467B2/ja active Active
  • 2011-11-28 US US13/988,852 patent/US9257607B2/en active Active
  • 2011-11-28 KR KR1020137016983A patent/KR101810234B1/ko active Active
  • 2011-11-28 CN CN201710233851.4A patent/CN107011904A/zh active Pending
  • 2011-11-28 EP EP11797150.7A patent/EP2646523B1/en active Active
  • 2011-11-28 BR BR112013013485-2A patent/BR112013013485B1/pt active IP Right Grant
  • 2011-11-28 CN CN201180058117XA patent/CN103314072A/zh active Pending
  • 2011-11-30 TW TW100144029A patent/TWI537364B/zh active

Patent Citations (7)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events