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Title: High-efficiency micro-energy generation based on free-carrier-modulated ZnO:N piezoelectric thin films

Abstract

The free-carrier-modulated ZnO:N thin film-based flexible nanogenerators (NZTF-FNGs) are proposed and experimentally demonstrated. The suggested flexible nanogenerators (FNGs) are fabricated using N-doped ZnO thin films (NZTFs) as their piezoelectric active elements, which are deposited by a radio frequency magnetron sputtering technique with an N{sub 2}O reactive gas as an in situ dopant source. Considerable numbers of N atoms are uniformly incorporated into NZTFs overall during their growth, which would enable them to significantly compensate the unintentional background free electron carriers both in the bulk and at the surface of ZnO thin films (ZTFs). This N-doping approach is found to remarkably enhance the performance of NZTF-FNGs, which shows output voltages that are almost two orders of magnitude higher than those of the conventionally grown ZnO thin film-based FNGs. This is believed to be a result of both substantial screening effect suppression in the ZTF bulk and more reliable Schottky barrier formation at the ZTF interfaces, which is all mainly caused by the N-compensatory doping process. Furthermore, the NZTF-FNGs fabricated are verified via charging tests to be suitable for micro-energy harvesting devices.

Authors:
; ; ; ;  [1]
  1. Department of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22300121
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 21; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ATOMS; CARRIERS; CRYSTAL GROWTH; DIFFUSION BARRIERS; DOPED MATERIALS; EFFICIENCY; ELECTRIC GENERATORS; ELECTRIC POTENTIAL; INTERFACES; MAGNETRONS; NITROGEN ADDITIONS; NITROUS OXIDE; PIEZOELECTRICITY; RADIOWAVE RADIATION; SCREENING; SPUTTERING; SURFACES; THIN FILMS; ZINC OXIDES

Citation Formats

Lee, Eunju, Park, Jaedon, Yim, Munhyuk, Jeong, Sangbeom, and Yoon, Giwan, E-mail: gwyoon@kaist.ac.kr. High-efficiency micro-energy generation based on free-carrier-modulated ZnO:N piezoelectric thin films. United States: N. p., 2014. Web. doi:10.1063/1.4880935.
Lee, Eunju, Park, Jaedon, Yim, Munhyuk, Jeong, Sangbeom, & Yoon, Giwan, E-mail: gwyoon@kaist.ac.kr. High-efficiency micro-energy generation based on free-carrier-modulated ZnO:N piezoelectric thin films. United States. doi:10.1063/1.4880935.
Lee, Eunju, Park, Jaedon, Yim, Munhyuk, Jeong, Sangbeom, and Yoon, Giwan, E-mail: gwyoon@kaist.ac.kr. Mon . "High-efficiency micro-energy generation based on free-carrier-modulated ZnO:N piezoelectric thin films". United States. doi:10.1063/1.4880935.
@article{osti_22300121,
title = {High-efficiency micro-energy generation based on free-carrier-modulated ZnO:N piezoelectric thin films},
author = {Lee, Eunju and Park, Jaedon and Yim, Munhyuk and Jeong, Sangbeom and Yoon, Giwan, E-mail: gwyoon@kaist.ac.kr},
abstractNote = {The free-carrier-modulated ZnO:N thin film-based flexible nanogenerators (NZTF-FNGs) are proposed and experimentally demonstrated. The suggested flexible nanogenerators (FNGs) are fabricated using N-doped ZnO thin films (NZTFs) as their piezoelectric active elements, which are deposited by a radio frequency magnetron sputtering technique with an N{sub 2}O reactive gas as an in situ dopant source. Considerable numbers of N atoms are uniformly incorporated into NZTFs overall during their growth, which would enable them to significantly compensate the unintentional background free electron carriers both in the bulk and at the surface of ZnO thin films (ZTFs). This N-doping approach is found to remarkably enhance the performance of NZTF-FNGs, which shows output voltages that are almost two orders of magnitude higher than those of the conventionally grown ZnO thin film-based FNGs. This is believed to be a result of both substantial screening effect suppression in the ZTF bulk and more reliable Schottky barrier formation at the ZTF interfaces, which is all mainly caused by the N-compensatory doping process. Furthermore, the NZTF-FNGs fabricated are verified via charging tests to be suitable for micro-energy harvesting devices.},
doi = {10.1063/1.4880935},
journal = {Applied Physics Letters},
number = 21,
volume = 104,
place = {United States},
year = {Mon May 26 00:00:00 EDT 2014},
month = {Mon May 26 00:00:00 EDT 2014}
}
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