New insights in the nanostructure and defect states of hydrogenated amorphous silicon obtained by annealing

J. Melskens, A. Smets, M. Schouten, S. Eijt, H. Schut, M. Zeman
{"title":"New insights in the nanostructure and defect states of hydrogenated amorphous silicon obtained by annealing","authors":"J. Melskens, A. Smets, M. Schouten, S. Eijt, H. Schut, M. Zeman","doi":"10.1109/pvsc-vol2.2012.6656760","DOIUrl":null,"url":null,"abstract":"Temperature annealing is used as a tool to study the validity of network models for the nanostructure of hydrogenated amorphous silicon (a-Si:H) and its relation to defect states. The changes in the size of the dominant open volume deficiencies have been studied using Doppler broadening positron annihilation spectroscopy and Fourier transform infrared spectroscopy. It is shown that the dominant open volume deficiencies for as-deposited films are divacancies, which appear to agglomerate into larger open volume deficiencies up to 400 °C. Above this temperature, the largest open volume deficiencies are suggested to be released at the surface of the sample. Fourier transform photocurrent spectroscopy results indicate a dramatic increase in the density of various subgap defect state distributions during temperature annealing. In addition, at least four defect states have been identified. These findings cannot be directly explained by assuming solely dangling bonds as the dominant defects in a-Si:H. We discuss that a model based on an anisotropic disordered network with volume deficiencies does explain our findings better than the classical model based on a continuous random network with solely an isotropic distribution of coordination defects. The claim is made that next to dangling bonds not fully hydrogen-passivated vacancies are significantly contributing to the dominant defect states in a-Si:H.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/pvsc-vol2.2012.6656760","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 3

Abstract

Temperature annealing is used as a tool to study the validity of network models for the nanostructure of hydrogenated amorphous silicon (a-Si:H) and its relation to defect states. The changes in the size of the dominant open volume deficiencies have been studied using Doppler broadening positron annihilation spectroscopy and Fourier transform infrared spectroscopy. It is shown that the dominant open volume deficiencies for as-deposited films are divacancies, which appear to agglomerate into larger open volume deficiencies up to 400 °C. Above this temperature, the largest open volume deficiencies are suggested to be released at the surface of the sample. Fourier transform photocurrent spectroscopy results indicate a dramatic increase in the density of various subgap defect state distributions during temperature annealing. In addition, at least four defect states have been identified. These findings cannot be directly explained by assuming solely dangling bonds as the dominant defects in a-Si:H. We discuss that a model based on an anisotropic disordered network with volume deficiencies does explain our findings better than the classical model based on a continuous random network with solely an isotropic distribution of coordination defects. The claim is made that next to dangling bonds not fully hydrogen-passivated vacancies are significantly contributing to the dominant defect states in a-Si:H.
查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
退火对氢化非晶硅纳米结构和缺陷态的新认识
利用温度退火技术研究了氢化非晶硅(a- si:H)纳米结构网络模型的有效性及其与缺陷态的关系。利用多普勒展宽正电子湮灭光谱和傅里叶变换红外光谱研究了显性开放体积缺陷的大小变化。结果表明,沉积薄膜的主要开放体积缺陷是空位,当温度达到400°C时,空位会聚集成更大的开放体积缺陷。在此温度以上,建议在样品表面释放最大的开体积缺陷。傅里叶变换光电流光谱结果表明,在温度退火过程中,各种亚隙缺陷态分布的密度急剧增加。另外,至少确定了四种缺陷状态。这些发现不能通过假设悬空键是a-Si:H的主要缺陷来直接解释。我们讨论了基于具有体积缺陷的各向异性无序网络的模型比基于仅具有各向同性配位缺陷分布的连续随机网络的经典模型更好地解释了我们的发现。在悬空键旁边,未完全氢钝化的空位是导致a-Si:H中主要缺陷态的重要原因。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 去求助
来源期刊
自引率
0.00%
发文量
0
期刊最新文献
Initial operating experience of the 1.2-MW La Ola photovoltaic system The impact of selenisation on damp heat degradation of the CIGS back contact molybdenum Remote plasma chemical vapor deposition for high-efficiency ultra-thin ∼25-microns crystalline Si solar cells Study of point defects in ns pulsed-laser annealed CuInSe2 thin films Optical monitoring and control of three-stage coevaporated Cu(In1−xGax)Se2 by real-time spectroscopic ellipsometry
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1