Characterization of intrinsic subgap density-of-states in exfoliated MoS2 FETs using a multi-frequency capacitance-conductance technique

Abstract

A multi-frequency capacitance-conductance technique is proposed for characterizing the intrinsic density-of-states (DOS: gint(E)) inside an energy bandgap range (E-V < E < E-C) by de-embedding the structure-dependent parameters such as parasitic capacitance and resistance in a fabricated exfoliated molybdenum disulfide (MoS2) field effect transistor (EM-FET). The proposed technique uses the measured frequency-dispersive capacitance (Cm) and conductance (G(m)= 1/R-m= omega CmDm) data with the measured dissipation factor D-m(= G(m)/omega C-m) at a frequency range of 0.3 kHz to 10 kHz. To extract g(int)(E), an equivalent circuit model of the MoS2 FET converted from a two-element model for the parallel-mode (C-m-D-m) measurement was developed with this technique. (C) 2017 Author(s).