By Topic

Green-Light Nanocolumn Light Emitting Diodes With Triangular-Lattice Uniform Arrays of InGaN-Based Nanocolumns

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Katsumi Kishino ; Dept. of Eng. & Appl. Sci., Sophia Univ., Tokyo, Japan ; Koji Yamano

Green-light nanocolumn light emitting diodes (LEDs) consisting of triangular-lattice uniform arrays of InGaN-based nanocolumns with lattice constants of 245-350 nm were fabricated with TiO2 mask selective-area growth by RF-plasma-assisted molecular beam epitaxy. The built-in core/shell structure of InGaN/GaN multiple quantum wells was self-assembled, confining carriers in the core of the nanocolumns. The characteristics of the nanocolumn LEDs were evaluated at room temperature under dc current injection in the range from 4.5 to 450 A/cm2. The emission wavelengths were 515 to 550 nm, and small current-induced spectral blueshifts of 2-11 nm were observed. The linewidth narrowing at a low current density was very small for the nanocolumn LEDs, in which nanocolumns with the same size were homogeneously arranged. The sidewalls of the nanocolumns were passivated by the deposition of Al2O3, contributing to the elimination of current leakage paths. The external quantum efficiency was improved with the passivation. Radiation beam angular profiles of the nanocolumn LEDs were evaluated and directional beam radiation was observed at specific wavelengths, which was attributed to the photonic band edge of the periodic nanocolumn arrangement.

Published in:

IEEE Journal of Quantum Electronics  (Volume:50 ,  Issue: 7 )