Environmental effects on transport properties of PdSe2 field effect transistors

We study the effect of pressure, voltage sweeping rate and electron irradiation on the transfer character-istics of field effect transistors fabricated by using exfoliated palladium diselenide flake as transistorchannel and Ti/Au metallic electrodes as source and drain. The silicon substrate is used as gate, the flakebeing transferred on Si/SiO2substrate. We report ambipolar behavior for the devices under investigationand we demonstrate that external stimuli have dramatic effects on the transport properties. In particular,increasing the acquisition time (by using slower sweeping rate) we demonstrate that the hysteresisobserved in the transfer characteristics is widened. Electron irradiation, necessary for SEM imaging ofthe device, also dramatically affects the characteristics due to induced defects and consequent chargetrapping at PdSe2and SiO2. Finally, we demonstrate that the device can be tuned from n-type conductionin vacuum, to p-type conduction in atmospheric pressure