Open AccessOn the electric-field reservoir for III-nitride based deep ultraviolet light-emitting diodes
Author(s) -
Zihui Zhang,
Luping Li,
Yonghui Zhang,
Fujun Xu,
Qiang Shi,
Bo Shen,
Wengang Bi
Publication year - 2017
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.25.016550
Subject(s) - electric field , light emitting diode , ultraviolet , thermionic emission , optoelectronics , materials science , quantum efficiency , nitride , diode , drift velocity , optics , quantum well , gallium nitride , layer (electronics) , physics , electron , laser , composite material , quantum mechanics
The drift velocity for holes is strongly influenced by the electric field in the p-type hole injection layer for III-nitride based deep ultraviolet light-emitting diodes (DUV LEDs). In this work, we propose an electric-field reservoir (EFR) consisting of a p-Al x Ga 1-x N/p-GaN architecture to facilitate the hole injection and improve the internal quantum efficiency (IQE). The p-Al x Ga 1-x N layer in the EFR can well reserve the electric field that can moderately adjust the drift velocity and the kinetic energy for holes. As a result, we are able to enhance the thermionic emission for holes to cross over the p-EBL with a high Al composition provided that the composition in the p-Al x Ga 1-x N layer is properly optimized to avoid a complete hole depletion therein.