1. Improved quality nonpolar a -plane GaN/AlGaN UV LEDs grown with sidewall lateral epitaxial overgrowth (SLEO)
- Author
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Kwang-Choong Kim, Umesh K. Mishra, Stacia Keller, Ben Haskell, James S. Speck, Steven P. DenBaars, Shuji Nakamura, M. C. Schmidt, Siddharth Rajan, Feng Wu, Tom Mates, Bilge Imer, and Barry Zhong
- Subjects
Equivalent series resistance ,business.industry ,Chemistry ,Surfaces and Interfaces ,Chemical vapor deposition ,Condensed Matter Physics ,Epitaxy ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention ,Laser linewidth ,Optics ,Planar ,law ,Materials Chemistry ,Optoelectronics ,Quantum efficiency ,Electrical and Electronic Engineering ,business ,Light-emitting diode ,Diode - Abstract
High quality nonpolar a -plane GaN templates were grown by utilizing sidewall lateral epitaxial overgrowth (SLEO) technique with threading dislocation density of ∼106–107 cm–2. 360 nm GaN/AlGaN multiple quantum well ultraviolet light emitting diodes were grown with metalorganic chemical vapor deposition. Reduced defect density SLEO a- plane, planar a -plane, and planar c -plane templates were co-loaded for device growth and processed together in order to make relative device performance comparison. For SLEO a -plane LEDs E EL peak position was measured at 360 nm and it was independent of drive current. The linewidth of the emission was 7 nm. The series resistance of these diodes was as low as 16.5 Ω and the forward voltage was measured as 4.08 V at 20 mA. The external quantum efficiency of the high quality SLEO a -plane devices was ∼275× higher than planar a -plane devices. The highest output power was realized at 200 mA as 65 μW. The effect of contact geometry on electrical and optical characteristics of the devices was also discussed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) more...
- Published
- 2008
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