Highly efficient all‐nitride phosphor‐converted white light emitting diode

The development and demonstration of a highly efficient warm‐white all‐nitride phosphor‐converted light emitting diode (pc‐LED) is presented utilizing a GaN based quantum well blue LED and two novel nitrogen containing luminescent materials, both of which are doped with Eu2+. For color conversion of the primary blue the nitridosilicates M2Si5N8 (orange‐red) and MSi2O2N2 (yellow‐green), with M = alkaline earth, were employed, thus achieving a high luminous efficiency (25 lumen/W at 1 W input), excellent color quality (correlated color temperature CCT = 3200 K, general color rendering index Ra > 90) and the highest proven color stability of any pc‐LED obtained so far. Thus, these novel all‐nitride LEDs are superior to both incandescent and fluorescent lamps and may therefore become the next generation of general lighting sources. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

[1]  C. Jørgensen CHAPTER 12 – CHEMICAL BONDING , 1962 .

[2]  C. W. Struck,et al.  Unified model of the temperature quenching of narrow-line and broad-band emissions , 1975 .

[3]  H. Amano,et al.  P-Type Conduction in Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI) , 1989 .

[4]  Takashi Mukai,et al.  InxGa(1−x)N/InyGa(1−y)N superlattices grown on GaN films , 1993 .

[5]  W. Schnick,et al.  Nitrido‐silicate. II [1]. Hochtemperatur‐Synthesen und Kristallstrukturen von Sr2Si5N8 und Ba2Si5N8 , 1995 .

[6]  Shuji Nakamura,et al.  Present performance of InGaN-based blue/green/yellow LEDs , 1997, Photonics West.

[7]  W. Schnick,et al.  Eu2Si5N8 and EuYbSi4N7. The first nitridosilicates with a divalent rare earth metal , 1997 .

[8]  W. Schnick,et al.  Nitridosilicates‐A Significant Extension of Silicate Chemistry , 1997 .

[9]  Regina Mueller-Mach,et al.  White-light-emitting diodes for illumination , 2000, Photonics West - Optoelectronic Materials and Devices.

[10]  H. Höppe,et al.  Luminescence in Eu 2+ -doped Ba 2 Si 5 N 8 : fluorescence, thermoluminescence, and upconversion , 2000 .

[11]  Michael R. Krames,et al.  High-power phosphor-converted light-emitting diodes based on III-Nitrides , 2002 .

[12]  Hyperfine interactions in the 13 K ferromagnet Eu2Si5N8 , 2002 .

[13]  Regina Mueller-Mach,et al.  Illumination-grade white LEDs , 2002, SPIE Optics + Photonics.

[14]  M. Whangbo,et al.  Syntheses, Structures, and Optical Properties of Yellow Ce2SiS5, Ce6Si4S17, and Ce4Si3S12 Materials , 2003 .

[15]  P. Dorenbos Locating lanthanide impurity levels in the forbidden band of host crystals , 2004 .

[16]  F. Stadler,et al.  Ca[Si2o2n2]: A novel layer silicate , 2004 .

[17]  Michael R. Krames,et al.  Phosphor materials and combinations for illumination-grade white pcLEDs , 2004, SPIE Optics + Photonics.