Article Title

Enhanced photoresponse of Cu₂O/ZnO heterojunction with piezo-modulated interface engineering

Authors

Pei Lin, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Xiang Chen, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Xiaoqin Yan, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Zheng Zhang, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Haoge Yuan, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Peifeng Li, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Yanguang Zhao, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
Yue Zhang, State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China Key Laboratory of New Energy Materials and Technologies, University of Science and Technology Beijing, Beijing 100083, China

Keywords

all-oxide device, piezotronic effect, interface modulation, enhanced photoresponse

Abstract

The ability to arbitrarily regulate semiconductor interfaces provides the most effective way to modulate the performance of optoelectronic devices. However, less work has been reported on piezo-modulated interface engineering in all-oxide systems. In this paper, an enhanced photoresponse of an all-oxide Cu2O/ZnO heterojunction was obtained by taking advantage of the piezotronic effect. The illumination density-dependent piezoelectric modulation ability was also com- prehensively investigated. An 18.6% enhancement of photoresponse was achieved when applying a –0.88% compressive strain. Comparative experiments confirmed that this enhancement could be interpreted in terms of the band modification induced by interfacial piezoelectric polarization. The positive piezopotential generated at the ZnO side produces an increase in space charge region in Cu2O, thus providing an extra driving force to separate the excitons more efficiently under illumination. Our research provides a promising method to boost the performance of optoelectronics without altering the interface structure and could be extended to other metal oxide devices.

Graphical Abstract

DOI

https://doi.org/10.1007/s12274-014-0447-6

Publisher

Tsinghua University Press

Recommended Citation

Pei Lin,Xiang Chen,Xiaoqin Yan,Zheng Zhang,Haoge Yuan,Peifeng Li,Yanguang Zhao,Yue Zhang, Enhanced photoresponse of Cu2O/ZnO heterojunction with piezo-modulated interface engineering. NanoRes.2014, 7(6): 860–868