Effects of Charge Trapping at the MoS2-SiO2 Interface on the Stability of Subthreshold Swing of MoS2 Field Effect Transistors

Xinnan Huang; Yao Yao; Songang Peng; Dayong Zhang; Jingyuan Shi; Zhi Jin

doi:10.3390/ma13132896

Effects of Charge Trapping at the MoS₂-SiO₂ Interface on the Stability of Subthreshold Swing of MoS₂ Field Effect Transistors

Materials (Basel). 2020 Jun 28;13(13):2896. doi: 10.3390/ma13132896.

Authors

Xinnan Huang^{1

2}, Yao Yao^{1

2}, Songang Peng^{1

2}, Dayong Zhang^{1

2}, Jingyuan Shi^{1

2}, Zhi Jin^{1

2}

Affiliations

¹ High-Frequency High-Voltage Device and Integrated Circuits R&D Center, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China.
² University of Chinese Academy of Sciences, Beijing 100049, China.

Abstract

The stability of the subthreshold swing (SS) is quite important for switch and memory applications in logic circuits. The SS in our MoS₂ field effect transistor (FET) is enlarged when the gate voltage sweep range expands towards the negative direction. This is quite different from other reported MoS₂ FETs whose SS is almost constant while varying gate voltage sweep range. This anomalous SS enlargement can be attributed to interface states at the MoS₂-SiO₂ interface. Moreover, a deviation of SS from its linear relationship with temperature is found. We relate this deviation to two main reasons, the energetic distribution of interface states and Fermi level shift originated from the thermal activation. Our study may be helpful for the future modification of the MoS₂ FET that is applied in the low power consumption devices and circuits.

Keywords: MoS2 FET; hysteresis; interface states; subthreshold swing; transition metal dichalcogenides (TMDCs).

Publication types

Letter

Abstract

Publication types

Grants and funding