The National Energy Technology Laboratory (NETL), on behalf of the U.S. Department of Energy (DOE), has announced the selection of four projects for solid-state lighting (SSL), in response to SSL Core Technology Research Call DE-PS26-09NT013775, for DOE and federal laboratories.
This is the sixth round in a series in which the DOE is examining high-priority research and development activities that will advance state-of-the-art SSL used for general-illumination applications. The selections have a total value of $6.4 million. Three of the selections will be funded via the American Recovery and Reinvestment Act ($4.6 million) and one will be funded via appropriated funds ($1.8 million).
Here are the selections:
Recipient: National Renewable Energy Laboratory
Title: Lattice mismatched GaInP alloys for color mixing white light LEDs
Funding Source: American Recovery and Reinvestment Act
Summary: The project seeks to demonstrate the viability of high-bandgap gallium indium phosphide alloys for synthesis of inexpensive, efficient aluminum-free LED devices on conventional gallium arsenide substrates, which emit in the deep-green region (560 nm to 570 nm) of the green gap, or inside the red gap (615 nm to 625 nm), and for which the LEDs are fabricated using simpler organometallic vapor-phase epitaxy (OMVPE) growth and processing techniques conventionally used for gallium arsenide based III-V alloys. The use of more-efficient emitters, particularly in the deep-green area of the spectrum, will contribute to meeting DOE efficiency targets identified for red-green-blue (RGB) based color-mixing LEDs, and significantly lower the cost of such devices.
Recipient: Pacific Northwest National Laboratory
Title: Development of Stable Materials for High-Efficiency Blue OLEDs through Rational Design.
Funding Source: American Recovery and Reinvestment Act
Summary: This project seeks to use new materials in a mixed-host system to demonstrate improved lifetime and efficiency. Using new stable materials and improved OLED device architectures will enable higher device stability and improved efficiencies in blue OLEDs at currents useful for SSL products, and lead to demonstration of highly efficient white OLEDs with longer lifetimes.
Recipient: Sandia National Laboratories
Title: Semi-polar GaN Materials Technology for High IQE Green LEDs
Funding Source: American Recovery and Reinvestment Act
Summary: This project seeks to improve the internal quantum efficiency (IQE) in green nitride-based LED structures by using semi-polar gallium nitride (GaN) planar orientations for indium gallium nitride (InGaN) multiple-quantum-well (MQW) growth. These semi-polar orientations have the advantage of significantly reducing the piezoelectric fields that distort the quantum-well band structure and decrease electron-hole overlap. At the end of this program, SNL expects MQW active regions at 540 nm with an IQE of 50%, which with an 80% light-extraction efficiency should produce LEDs with an external quantum efficiency of 40%, or twice the estimated current state-of-the-art.
Recipient: U.S. Army Research Laboratory
Title: Exploiting Negative Polarization Charge at n-InGaN/p-GaN Heterointerfaces to Achieve High Power Green LEDs without Efficiency Droop
Funding Source: Solid-State Lighting Appropriated Funds
Summary: This project seeks to exploit the negative polarization charge at the n-InGaN/p-GaN heterointerface to achieve high-power, high-efficiency green LEDs without efficiency droop. The target goals are 540 nm LEDs with a peak IQE of 40% at current densities sufficient to enable general-illumination applications.
