Open AccessDual-wavelength GaN-based LEDs grown on truncated hexagonal pyramids formed by selective-area regrowth on Si-implanted GaN templates
Author(s) -
Ming Lun Lee,
Yu Min Yeh,
Shang Ju Tu,
P. C. Chen,
Ming Jui Wu,
Wei Chih Lai,
Jinn-Kong Sheu
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.00a864
Subject(s) - light emitting diode , materials science , cathodoluminescence , optoelectronics , epitaxy , electroluminescence , quantum well , gallium nitride , transmission electron microscopy , diode , metalorganic vapour phase epitaxy , hexagonal crystal system , layer (electronics) , optics , luminescence , crystallography , nanotechnology , laser , chemistry , physics
GaN-based blue light-emitting diodes (LEDs) with micro truncated hexagonal pyramid (THP) array were grown on selective-area Si-implanted GaN (SIG) templates. The GaN epitaxial layer regrown on the SIG templates exhibited selective growth and subsequent lateral growth to form the THP array. The observed selective-area growth was attributed to the different crystal structures between the Si-implanted and implantation-free regions. Consequently, LEDs grown on the GaN THP array emitted broad electroluminescence spectra with multiple peaks. Spatially resolved cathodoluminescence revealed that the broad spectra originated from different areas within each THP. Transmission electron microscopy showed the GaN-based epitaxial layers, including InGaN/GaN multi-quantum wells regrown at different growth rates (or with different In content in the InGaN wells) between the semi-polar and c-face planes of each THP.