High-performance CuS/n-Si heterojunction photodetectors prepared by e-beam evaporation of Cu films as precursor layers

• Published in: Journal of alloys and compounds Vol. 884; p. 161121
• Main Authors: Xu, Yajun, Shen, Honglie, Zhang, Jingzhe, Zhao, Qichen, Wang, Zehui, Xu, Binbin, Zhang, Wei
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.12.2021; Elsevier BV
• Subjects: Aluminum oxide; Copper; Copper sulfides; CuS/n-Si heterojunction; E-beam evaporation; Electromagnetic absorption; Electron beams; Evaporation; Heterojunctions; Metal films; Optoelectronics; Photodetectors; Photometers; Precursors; Self-powered; Silicon; Silicon wafers; Silver; Substrates; Sulphuration temperature; Transition metal compounds; Sulphuration temperature; Photodetectors; CuS/n-Si heterojunction; Self-powered; E-beam evaporation
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.161121

•CuS films were prepared by e-beam evaporation of Cu films as precursor layers.•n-type Si wafers with inverted pyramid were used to enhanced device performance.•The CuS/n-Si PDs showed a self-driven R of 0.41 A/W and a rise time of 17 μs.•The CuS/n-Si heterojunction PDs demonstrated an EQE of 51.91% at 980 nm. Transition metal dichalcogenides (TMDCs) are considered to be the most promising next-generation materials for electronics and optoelectronics due to their excellent properties. In this work, well-performing CuS films were prepared by e-beam evaporation of Cu films as precursor layers. Ag/n-Si/Al2O3/CuS/ITO heterojunction photodetector with high responsivity (0.41 A·W−1), detectivity (1.739 × 1011 Jones) and fast response speed (17 μs) at zero bias were prepared by optimising sulphuration temperature and using silicon wafers with inverted pyramid light-trapping structures as substrates. Besides, the photodetector exhibited excellent light absorption ability, with an EQE of 51.91% at 980 nm. All these results demonstrated that excellent photodetector materials can be obtained by using metal films as precursor layers, which provides novel ideas and methods for the synthesis of TMDCs materials.