High-Frequency Performance of MoS2 Transistors at Cryogenic Temperatures

Recently, due to its potential in high-speed flexible electronics, radio-frequency transistors based on two-dimensional MoS ₂ has attracted the interest of researchers. However, for the moment, little is known on the RF performance of MoS ₂ transistors at cryogenic temperatures, which is important for evaluating performance limits of high-frequency MoS ₂ devices. In this work, we report the RF performance of MoS ₂ transistors at cryogenic temperatures based on chemical vapor deposited bilayer MoS ₂ for the first time. As the temperature reduces, the higher cut-off frequency was achieved. At the liquid helium temperature, extrinsic and intrinsic fT of 5.7 and 12.7 GHz for the transistor with 300 nm gate-length were achieved. Furthermore, saturation velocity and intrinsic fmax of 2.4×10 ⁶ cm/s and 24 GHz were obtained at 4.3 K, respectively. The revealed high-frequency performances of MoS ₂ transistors at cryogenic temperatures are helpful to the advancement of MoS ₂ high-frequency electronics.