4.7 Article

Improving the p-type conductivity of Cu2O thin films by Ni doping and their heterojunction with n-ZnO

期刊

APPLIED SURFACE SCIENCE
卷 590, 期 -, 页码 -

出版社

ELSEVIER
DOI: 10.1016/j.apsusc.2022.153047

关键词

p -type transparent oxide semiconductors; Cuprous oxide; Rapid thermal annealing; Heterojunction; Energy band offsets

资金

  1. General Research Fund of the Research Grants Council of Hong Kong SAR, China [CityU 11305119]
  2. CityU SRG-Fd [11212118]
  3. CityU SGP [9380076]

向作者/读者索取更多资源

Cu2O can exhibit enhanced p-type conductivity through Ni doping, and rapid thermal annealing leads to significant improvement in the crystallinity and conductivity of the alloy films.
Cu2O is one of the few transition metal oxides which can exhibit p-type conductivity due to native acceptor defects. Further improvements in the p-type conductivity of Cu2O can be achieved via extrinsic doping and post-growth processing. In this work, we investigate the effects of Ni doping in Cu2O with Ni content up to ~11%. A variety of analytical techniques were utilized to investigate the structural, optical and electrical properties of these alloy thin films. We find that the incorporation of Ni improves the p-type conductivity of the films without altering the Cu2O crystallographic structure and maintains a wide bandgap of ~2.5 eV. X-ray photoelectron spectroscopy (XPS) measurements reveal that the Fermi level moves closer to the valence band with increasing x, in agreement with the increasing hole concentration. Significant improvement in the crystallinity as well as the p-type conductivity of the alloy films can be observed after rapid thermal annealing (RTA). In particular, alloys with x >= 0.005 exhibit a high hole mobility mu~12-22 cm(2)/V-s with low resistivity of rho~30-60 omega-cm and free hole concentration N~1x10(16) cm(-3) after RTA in air-N-2 ambient at 700?. Such improvement can be attributed to the formation of Cu vacancies which promotes Ni substitution in the presence of small amount O-2 in the air-N-2 annealing environment. Finally, we fabricated a transparent p-(NixCu1-x)(2)O/n-ZnO heterojunction and evaluated its junction performance. XPS measurements reveal a type II band offset of this heterojunction with valence band and conduction band offsets of 2.81 eV and 2.07 eV, respectively. The heterojunction exhibits both rectification and photovoltaic response, demonstrating its potential for p-n junction and photodetection devices.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据