Light-Induced Peroxide Formation in ZnO: Origin of Persistent Photoconductivity

Cited 3 time in webofscience Cited 0 time in scopus
121 Viewed 15 Downloaded
Title
Light-Induced Peroxide Formation in ZnO: Origin of Persistent Photoconductivity
Author(s)
Youngho Kang; Ho-Hyun Nahm; seungwu Han
Publication Date
2016-10
Journal
SCIENTIFIC REPORTS, v.6, no., pp.35148 -
Publisher
NATURE PUBLISHING GROUP
Abstract
The persistent photoconductivity (PPC) in ZnO has been a critical problem in opto-electrical devices employing ZnO such as ultraviolet sensors and thin film transistors for the transparent display. While the metastable state of oxygen vacancy (V-O) is widely accepted as the microscopic origin of PPC, recent experiments on the influence of temperature and oxygen environments are at variance with the V-O model. In this study, using the density-functional theory calculations, we propose a novel mechanism of PPC that involves the hydrogen-zinc vacancy defect complex (2H-V-Zn). We show that a substantial amount of 2H-V-Zn can exist during the growth process due to its low formation energy. The light absorption of 2H-V-Zn leads to the metastable state that is characterized by the formation of O-2(2-) (peroxide) around the defect, leaving the free carriers in the conduction band. Furthermore, we estimate the lifetime of photo-electrons to be similar to 20 secs, which is similar to the experimental observation. Our model also explains the experimental results showing that PPC is enhanced (suppressed) in oxygen-rich (low-temperature) conditions. By revealing a convincing origin of PPC in ZnO, we expect that the present work will pave the way for optimizing optoelectronic properties of ZnO. © The Author(s) 2016
URI
https://pr.ibs.re.kr/handle/8788114/3045
ISSN
2045-2322
Appears in Collections:
Center for Correlated Electron Systems(강상관계 물질 연구단) > Journal Papers (저널논문)
Files in This Item:
Light-Induced Peroxide Formation in ZnO Origin of Persistent Photoconductivity.pdfDownload

qrcode

  • facebook

    twitter

  • Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
해당 아이템을 이메일로 공유하기 원하시면 인증을 거치시기 바랍니다.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse