"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."
The objective of this research is exploration of a growth and device processing technique to improve the energy efficiency and reduce the cost of light emitting diodes for solid state lighting. Key challenges to the widespread implementation of these illumination devices include lifetime at high output powers, internal quantum efficiency of green emitters, and the cost of solid state sources. Such challenges result from the use of thermally and electrically insulating substrate materials which are incompatible with the device layers.
The approach of this research is development of vertical transport devices through a two-step hybrid growth process. The first step employs low temperature integration of a chemically soluble layer; the second step explores the high-temperature overgrowth of device-quality material. Standard one-step growth techniques limit the integration of dissimilar materials due to interfacial reactions and interdiffusion of impurities, which can be avoided through hybrid growth. This work will systematically investigate the effects of processing, regrowth, and chemical liftoff on these materials and will ultimately compare the light extraction and thermal management benefits of this route with existing device technologies.
The broader impacts of this work are significant in both the areas of educational outreach and potential economic development for the state. The outreach portion will provide hands-on lighting and energy engineering demonstrations to students at rural and urban middle schools populated by underrepresented groups. Successful implementation of this proposal will position the investigators for other economic development opportunities in the state, helping Oklahoma transition its leadership in energy to green technologies.
