DocumentCode :
43696
Title :
Au-Mediated Surface Plasmon Enhanced Ultraviolet Response of p-Si/n-ZnO Nanorods Photodetectors
Author :
Jun-Dar Hwang ; Lai, M.J. ; Chen, H.Z. ; Kao, M.C.
Author_Institution :
Dept. of Electrophys., Nat. Chiayi Univ., Chiayi, Taiwan
Volume :
26
Issue :
10
fYear :
2014
fDate :
15-May-14
Firstpage :
1023
Lastpage :
1026
Abstract :
Surface plasmon resonance mediated by Gold (Au) nanoparticles (NPs) was employed to enhance the ultraviolet (UV) response of p-Si/n-ZnO nanorod (NR) heterojunction photodetectors (HPDs). In the ZnO NRs with Au NP covering, the photoluminescence spectrum shows that the band-to-band emission of ZnO (384 nm) is increased by a magnitude of 3, and the deep-level emissions (450-700 nm) are drastically decreased as compared with HPDs without coverings of Au NPs. Such a result increases UV-to-visible rejection ratio from 214 to 6180 and it attributes that the defect-level emissions of ZnO induce surface plasmon resonance in Au NPs and then enhances the emissions, exciting a large quantity of electrons crossing over the Au NP/ZnO interface barrier. Consequently, these electrons are transferred to the ZnO conduction band from the Au NPs, causing a photocurrent gain and the quantum efficiency is as high as 1157% at 2 V reverse bias.
Keywords :
II-VI semiconductors; conduction bands; deep levels; elemental semiconductors; gold; nanoparticles; nanophotonics; nanorods; p-n heterojunctions; photoconductivity; photodetectors; photoluminescence; silicon; surface plasmons; ultraviolet spectra; visible spectra; wide band gap semiconductors; zinc compounds; Au-Si-ZnO; UV-to-visible rejection ratio; band-to-band emission; conduction band; deep-level emissions; gold nanoparticles; interface barrier; nanorods; p-n heterojunction photodetectors; photocurrent gain; photoluminescence spectrum; quantum efficiency; surface plasmon enhanced ultraviolet response; voltage 2 V; Gold; Nanoparticles; Photoconductivity; Plasmons; Substrates; Surface treatment; Zinc oxide; Au nanoparticles; Surface plasmon resonance; ZnO nanorod; heterojunction photodetectors;
fLanguage :
English
Journal_Title :
Photonics Technology Letters, IEEE
Publisher :
ieee
ISSN :
1041-1135
Type :
jour
DOI :
10.1109/LPT.2014.2312734
Filename :
6776410
Link To Document :
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