Self-assembled monolayer for interface engineering and gate dielectric film

Abstract

This study describes a concept for interface engineering by means of a SAM (self-assembled monolayer)-based dielectric in molybdenum disulfide (MoS₂) field-effect transistors. A simple fabrication process involving the selective formation of a SAM on metal oxides in conjunction with the dry transfer of MoS₂ flakes was established. A subthreshold slope (SS) of 69 mV/dec and no hysteresis were demonstrated with the ultrathin SAM-based gate dielectrics accompanied by a low gate leakage current. The small SS and no hysteresis indicate the superior interfacial properties of the MoS₂/SAM structure. Cross-sectional transmission electron microscopy revealed the sharp and abrupt interface of the MoS₂/SAM structure. This work opens up interesting directions for research and development of 2-dimensional materials-based devices.