Investigation of charge trapping mechanism in MoS2 field effect transistor by incorporating Al into host La2O3 as gate dielectric.

Charge trapping effect plays a key role in multibit memory devices and Brain-like neuron device. Herein, MoS2 field-effect transistors are fabricated with incorporating Al into host La2O3 as gate dielectric, and exhibit excellent electrical properties with an on-off ratio in memory window of ~106 and memory window ratio of ~40%. Furthermore, the charge trapping and de-trapping process were systematically studied, and the time constants are obtained from time domain characteristics. Make use of the charge trapping effect, the threshold voltage of the device can be continuously adjusted. The oxide layer trap density and the interface state trap density are extracted using the charge separation method. These theoretical studies provide a deeper understanding for controlling the charge trapping process, benefitting for the commercialization of two-dimensional electronic devices and the development of new charge trapping devices.