Multiparameter admittance spectroscopy for investigating defects in MoS₂ thin film MOSFETs

A method for assessing the quality of electronic material properties of thin-film metal oxide semiconductor field-effect transistors (MOSFETs) is presented. By investigating samples with MOCVD-grown MoS₂ channels exposed to atmospheric conditions, the existence of electron traps in MoS₂ and at the interface between the gate insulator and the thin-film MoS₂ are revealed. Differential conductance and capacitance data of the transistor channels are plotted as 3D surfaces on a base plane spanned by the measurement frequency versus the gate voltage. The existence of defects is confirmed by comparison with ideal results from a theoretical model.