In this paper, the electrical properties of a FET based on nanoribbon of transition metal dichalcogenides in the presence of S-vacancy are investigated. The transition metal dichalcogenides (MoS2, MoSe2, WS2, and WSe2) monolayer is utilized as the channel for the FET. The non-equilibrium Green’s function (NEGF) along with the tight-binding method has been employed to study the electrical properties. The local density of states for pristine and defective ribbons are compared and the creation of mid-gap states due to S-vacancy is explored. The I-V characteristic of this FET is investigated. The increasing S-vacancy decreases ON-current whereas, leads to the increment of OFF-current. The considering 1.75% vacancy can decline ON-current 12 times for WSe2 and increases OFF-current 35 times for MoSe2.
