title: Self-Powered, High-Speed and Visible-Near Infrared Response of MoO(3-x)/n-Si Heterojunction Photodetector with Enhanced Performance by Interfacial Engineering.
abstract: Photodetectors with a wide spectrum response are important components for sensing, imaging, and other optoelectronic applications. A molybdenum oxide (MoO(3-x))/Si heterojunction has been applied as solar cells with great success, but its potential in photodetectors has not been explored yet. Herein, a self-powered, high-speed heterojunction photodetector fabricated by coating an n-type Si hierarchical structure with an ultrathin hole-selective layer of molybdenum oxide (MoO(3-x)) is first investigated. Excellent and stable photoresponse performance is obtained by using a methyl group passivated interface. The heterojunction photodetector demonstrated high sensitivity to a wide spectrum from 300 to 1100 nm. The self-powered photodetector shows a high detectivity of (∼6.29 × 10(12) cmHz(1/2) W(-1)) and fast response time (1.0 μs). The excellent photodetecting performance is attributed to the enhanced interfacial barrier height and three-dimensional geometry of Si nanostructures, which is beneficial for efficient photocarrier collection and transportation. Finally, our devices show excellent long-term stability in air for 6 months with negligible performance degradation. The thermal evaporation method for large-scale fabrication of MoO(3-x)/n-Si photodetectors makes it suitable for self-powered, multispectral, and high-speed response photodetecting applications.
authors.affiliation: Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Chuanxi
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Liang
authors.affiliation: Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Mingze
authors.initials: M
authors.lastname: Su
authors.affiliation: Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Pengyi
authors.initials: P
authors.lastname: Liu
authors.affiliation: Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Mai
authors.affiliation: Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Weiguang
authors.initials: W
authors.lastname: Xie
keywords: heterojunction; high speed; interface passivation; photodetector; self-powered