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Title: Ultraviolet electroluminescence from ZnO/p-Si heterojunctions

Abstract

Nominally undoped ZnO films were deposited by reactive sputtering on the lightly boron-doped (p{sup -}) and heavily boron-doped (p{sup +}) silicon substrates. The sputtered ZnO films were identified to be highly <002> oriented in crystallinity and n type in electrical conductivity. The current-voltage (I-V) characteristics revealed that the ZnO/p{sup -}-Si heterojunction exhibited well-defined rectifying behavior while the ZnO/p{sup +}-Si heterojunction did not possess rectifying function. As for the ZnO/p{sup +}-Si heterojunction, it was electroluminescent to a certain extent in the visible region under sufficient forward bias with the positive voltage on the silicon substrate, while it emitted ultraviolet light characteristics of near-band-edge emission of ZnO under the reverse bias, which significantly dominated the visible emission. In contrast to the ZnO/p{sup +}-Si heterojunction, the ZnO/p{sup -}-Si heterojunction did not exhibit detectable electroluminescence (EL) under either forward or reverse bias. The I-V characteristics and EL mechanism of the above-mentioned heterojunctions have been tentatively explained in terms of the energy-band structures of the heterojunctions.

Authors:
; ;  [1]
  1. State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)
Publication Date:
OSTI Identifier:
20982713
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 5; Other Information: DOI: 10.1063/1.2464185; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BORON; DEPOSITION; DOPED MATERIALS; ELECTRIC CONDUCTIVITY; ELECTRIC POTENTIAL; ELECTROLUMINESCENCE; HETEROJUNCTIONS; SEMICONDUCTOR MATERIALS; SILICON; SPUTTERING; SUBSTRATES; THIN FILMS; ULTRAVIOLET RADIATION; ZINC OXIDES

Citation Formats

Chen, Peiliang, Ma, Xiangyang, and Yang, Deren. Ultraviolet electroluminescence from ZnO/p-Si heterojunctions. United States: N. p., 2007. Web. doi:10.1063/1.2464185.
Chen, Peiliang, Ma, Xiangyang, & Yang, Deren. Ultraviolet electroluminescence from ZnO/p-Si heterojunctions. United States. doi:10.1063/1.2464185.
Chen, Peiliang, Ma, Xiangyang, and Yang, Deren. Thu . "Ultraviolet electroluminescence from ZnO/p-Si heterojunctions". United States. doi:10.1063/1.2464185.
@article{osti_20982713,
title = {Ultraviolet electroluminescence from ZnO/p-Si heterojunctions},
author = {Chen, Peiliang and Ma, Xiangyang and Yang, Deren},
abstractNote = {Nominally undoped ZnO films were deposited by reactive sputtering on the lightly boron-doped (p{sup -}) and heavily boron-doped (p{sup +}) silicon substrates. The sputtered ZnO films were identified to be highly <002> oriented in crystallinity and n type in electrical conductivity. The current-voltage (I-V) characteristics revealed that the ZnO/p{sup -}-Si heterojunction exhibited well-defined rectifying behavior while the ZnO/p{sup +}-Si heterojunction did not possess rectifying function. As for the ZnO/p{sup +}-Si heterojunction, it was electroluminescent to a certain extent in the visible region under sufficient forward bias with the positive voltage on the silicon substrate, while it emitted ultraviolet light characteristics of near-band-edge emission of ZnO under the reverse bias, which significantly dominated the visible emission. In contrast to the ZnO/p{sup +}-Si heterojunction, the ZnO/p{sup -}-Si heterojunction did not exhibit detectable electroluminescence (EL) under either forward or reverse bias. The I-V characteristics and EL mechanism of the above-mentioned heterojunctions have been tentatively explained in terms of the energy-band structures of the heterojunctions.},
doi = {10.1063/1.2464185},
journal = {Journal of Applied Physics},
number = 5,
volume = 101,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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