Comparison of InGaN/GaN light emitting diodes grown on m ‐plane and a ‐plane bulk GaN substrates |
| |
| Authors: | Hisashi Yamada Kenji Iso Makoto Saito Hirohiko Hirasawa Natalie Fellows Hisashi Masui Kenji Fujito James S. Speck Steven P. DenBaars Shuji Nakamura |
| |
| Affiliation: | 1. Materials Department, University of California, Santa Barbara, CA 93106, USA;2. Optoelectronics Laboratory, Mitsubishi Chemical Co., Ltd. 1000 Higashi‐Mamiana, Ushiku, Ibaraki 300‐1295, Japan |
| |
| Abstract: | InGaN/GaN‐based light emitting diodes (LEDs) grown on m ‐plane, a ‐plane and off‐axis between m ‐ and a ‐plane GaN bulk substrates were investigated. A smooth surface was obtained when a ‐plane substrate was applied; however, large amounts of defects were observed. Photoluminescence measurements of the LEDs with a well thickness of 2.5 nm revealed that all the LEDs showed the peak emission wavelength at 389 nm. The PL intensity of the a ‐plane LED is one order of magnitude lower than that of the m ‐plane LED. The a ‐plane LEDs showed significant lower electroluminescence output powers than m ‐plane LEDs, suggesting that excitons are trapped by the defects, which act as non‐radiative recombination centers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |
| |
| Keywords: | 42.72.Bj 78.55.Cr 85.60.Jb |
|
|
