16 March 2010 InGaN light-emitting diodes with highly transparent ZnO:Ga electrodes
Author Affiliations +
Proceedings Volume 7602, Gallium Nitride Materials and Devices V; 76020I (2010) https://doi.org/10.1117/12.853327
Event: SPIE OPTO, 2010, San Francisco, California, United States
Abstract
InGaN light-emitting diodes (LEDs) utilizing ZnO layers heavily doped with Ga (GZO) as transparent p-electrodes were fabricated and their characteristics were demonstrated to be superior to those of LEDs with metal Ni/Au electrodes. Highly conductive and highly transparent GZO films were grown on p-GaN contact layers of the LED structures by plasma-assisted molecular beam epitaxy under metal-rich conditions. The c and a lattice constants of GZO were found to be close to the bulk values, indicating small lattice distortion of GZO. The as-grown GZO films showed resistivities as low as 2.2-2.9×10-4 Ω cm. Upon rapid thermal annealing at the optimum temperature of 675 °C, the resistivity decreased reaching a value of ~1.9×10-4 Ω cm. Unlike the LEDs with Ni/Au contacts, the LEDs with GZO electrodes showed no filamentation and very uniform light emission at high current densities. The peak value of the relative external quantum efficiency for the LEDs with GZO contacts has substantial improvement compared with that for the LEDs with Ni/Au contacts. Under pulsed excitation mode, GZO-LEDs withstood current densities up to 5000 A/cm2.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
H. Y. Liu, X. Li, X. Ni, V. Avrutin, N. Izyumskaya, Ü. Özgür, H. Morkoç, "InGaN light-emitting diodes with highly transparent ZnO:Ga electrodes", Proc. SPIE 7602, Gallium Nitride Materials and Devices V, 76020I (16 March 2010); doi: 10.1117/12.853327; https://doi.org/10.1117/12.853327
PROCEEDINGS
8 PAGES


SHARE
RELATED CONTENT


Back to Top