High-Speed Transition-Metal Dichalcogenides Based Schottky Photodiodes for Visible and Infrared Light Communication
Youwei Zhang, Shen Wang, Su Wu, Weijia Tang, Yantao Shu, Kankan Ma, Butian Zhang, Peng Zhou, Shun Wang
Abstract
Due to their atomically ultrathin thickness, the development of high-performance transition-metal dichalcogenides (TMDCs) based photodetectors demands device designs distinct from architectures adopted in conventional bulk semiconductor devices. Here, we demonstrate a field-induced Schottky barrier photodiode with three different TMDC materials, WSe2, MoTe2, and WS2. Owing to the high gate efficiency of a high-κ dielectric film, the Schottky barrier at metal contacts is effectively modulated by external bias, giving rise to a strong diode-like rectifying characteristic with high current on/off ratio. The WSe2 photodiode shows a linear dynamic range of 112 dB, a responsivity of 0.17 A/W, and response time of 8 ns. When this fast WSe2 device is employed for visible light communication data linking, a maximum real-time data transmission rate of 110 Mbps is achieved. Meanwhile, infrared light communication was also realized with a maximum data rate of 30 Mbps using a field-induced MoTe2 Schottky barrier photodiode as a light sensor. This work provides a general CMOS-compatible and controllable fabrication strategy for TMDC-based photodetectors.