High photosensitivity few-layered MoSe2 back-gated field-effect phototransistors

• Published in: Nanotechnology Vol. 25; no. 36; p. 365202
• Main Authors: Abderrahmane, A, Ko, P J, Thu, T V, Ishizawa, S, Takamura, T, Sandhu, A
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 12.09.2014; Institute of Physics
• Subjects: 2D materials; Applied sciences; Constraining; Electric potential; Electronics; Exact sciences and technology; Lasers; molybdenum diselenide; optoelectronic; Oxides; photodetector; Photosensitivity; phototransistor; Phototransistors; Quantum efficiency; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Transistors; Voltage; Voltage threshold; Field effect transistor; Photosensitivity; Optoelectronic properties; Gate oxide; Limiting factor; Silicon; Quantum yield; Gates
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/0957-4484/25/36/365202

In this paper, we report on the fabrication and optoelectronic properties of high sensitive phototransistors based on few-layered MoSe2 back-gated field-effect transistors, with a mobility of 19.7 cm2 V−1 s−1 at room temperature. We obtained an ultrahigh photoresponsivity of 97.1 AW−1 and an external quantum efficiency (EQE) of 22 666% using 532 nm laser excitation at room temperature. The photoresponsivity was improved near the threshold gate voltage; however, the selection of the silicon dioxide as a gate oxide represents a limiting factor in the ultimate performance. Thanks to their high photoresponsivity and external quantum efficiency, the few-layered MoSe2-based devices are promising for photoelectronic applications.