Enhancement of exciton radiative recombination for In-doped ZnO nanowires with aluminum cylindrical micropillars

• Published in: Journal of luminescence Vol. 136; pp. 11 - 16
• Main Authors: Wang, Jen-Cheng, Liang, Yu-Ting, Cheng, Fang-Ching, Fang, Chia-Hui, Chen, Hung-Ing, Tsai, Chung-Yuan, Jiang, Joe-Air, Nee, Tzer-En
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.04.2013; Elsevier
• Subjects: Aluminum; Arrays; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Cylindrical micropillar; Electron states; Emission; Exact sciences and technology; Excitation; Excitons and related phenomena; Ii-vi semiconductors; Luminescence; Materials science; Nanoscale materials and structures: fabrication and characterization; Nanowires; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; Quantum wires; Radiative recombination; Surface plasmon resonance; Zinc oxide; ZnO; Cylindrical micropillar; Surface plasmon resonance; ZnO; Nanowires; Annealing; Vacancies; Interband transitions; Transition element compounds; Doping; Photoluminescence; Radiative recombination; Doped materials; Binary compounds; Zinc Oxides; Indium additions; Quantum yield; Surface plasmons; Excitons; II-VI semiconductors; Surface defect; Zinc oxide; Defect formation
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2012.11.024

Zinc oxide (ZnO) has attracted intensive research effort in recent years, due to its unique properties and versatile applications. Recent work on the conservation of surface plasmon (SP) and light through period metal arrays has elucidated the propagation of SP resonance behavior. In this paper, we discuss the enhancement of exciton radiative recombination of the ZnO nanowires with Al cylindrical micropillars. Optical characterization of exciton interacted with SP resonance for indium-doped ZnO nanowires with Al cylindrical micropillars has been also investigated. From photoluminescence spectra of In-doped ZnO nanowires, it is found that the In-doped ZnO nanowires have a blue emission at 425nm, which resulted from the ZnO band-to-band transition. Prior to the arrays of samples were annealed, a broad green emission centered at 500nm was observed, which is attributed to ZnO native point defects. The relatively strong green band emission results from the radiative recombination that arises from the ionized oxygen vacancy and surface-defect related luminescence. Compare the In-doped ZnO on Si substrate, the enhancement of PL intensity for In-doped ZnO with deposited Al pattern film can be attributed to strong interaction with SP resonance and exciton over a broad temperature range. These experimental results indicate that Al cylindrical micropillars can significantly enhance carrier confinement and increase the quantum efficiency of In-doped ZnO/Al heterostructures due to the interaction of SP resonance between the In-doped ZnO nanowires and Al cylindrical micropillar structures, the surface-defect related luminescence, and the auxiliary test structures with variable micropillar parameters. ► We examine the exciton radiative recombination of the ZnO nanowires. ► Al cylindrical micropillars affect the carrier recombination of ZnO/Al structures. ► The interaction of SP resonance between In-doped ZnO nanowire and Al pattern film. ► The carrier transport was responsible for the influences in the optical properties.