Open AccessExciton localization and ultralow onset ultraviolet emission in ZnO nanopencils-based heterojunction diodes
Author(s) -
Junyan Jiang,
Yuantao Zhang,
Chi Chen,
Yan Liu,
Xu Han,
Bin Wu,
Baolin Zhang,
Guotong Du
Publication year - 2016
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.24.020938
Subject(s) - materials science , optoelectronics , ultraviolet , electroluminescence , exciton , diode , sapphire , photoluminescence , heterojunction , spontaneous emission , wafer , light emitting diode , wide bandgap semiconductor , quantum dot , quantum efficiency , optics , laser , nanotechnology , physics , condensed matter physics , layer (electronics)
n-GaN/i-ZnO/p-GaN double heterojunction diodes were constructed by vertically binding p-GaN wafer on the tip of ZnO nanopencil arrays grown on n-GaN/sapphire substrates. An increased quantum confinement in the tip of ZnO nanopencils has been verified by photoluminescence measurements combined with quantitative analyses. Under forward bias, a sharp ultraviolet emission at ~375 nm due to localized excitons recombination can be observed in ZnO. The electroluminescence mechanism of the studied diode is tentatively elucidated using a simplified quantum confinement model. Additionally, the improved performance of the studied diode featuring an ultralow emission onset, a good operation stability and an enhanced ultraviolet emission shows the potential of our approach. This work provides a new route for the design and development of ZnO-based excitonic optoelectronic devices.