Advanced Topics on Condensed Matter Physics
Department of Physics, NCU
Low Frequency Noise in Transition Metal Dichalcogenides
Speaker
王繼文
Low Temperature Physics Laboratory, Department of Physics
National Central University
Taiwan
Date 2016/09/22 (Thur)
Time 14.00
Place S4-625
Transition metal dichalcogenides (TMDC) are emergent 2D semiconducting materials with direct-band gap, which is essential for many applications including transistors. Herein, low-frequency noise and electrical transport property in CVD monolayer MoS2 and WS2 field-effect transistors are reported. The field-effect mobility of MoS2 and WS2 are 40 and 2 cm2/Vs accordingly. The low frequency noises of both MoS2 and WS2 devices show 1/f spectrum. For MoS2 devices, the spectrum follows Hooge empirical law. But for WS2 devices, the dependence on current deviates from Hooge empirical law significantly. We further apply ionic gel to MoS2 device as gate dielectric to explore 1/f noise in high carrier density region. The results demonstrate the CVD MoS2 and WS2 are high quality monolayer semiconductors and potentially suitable in applications on electronics and optoelectronics.