Molecular Doping of Multilayer MoS2 Field-effect Transistors: Reduction in Sheet and Contact Resistances

摘要

For the first time, polyethyleneimine (PEI) doping on multilayer MoS2field-effect transistors are investigated. A 2.6 times reduction in sheetresistance, and 1.2 times reduction in contact resistance have been achieved.The enhanced electrical characteristics are also reflected in a 70% improvementin ON current, and 50% improvement in extrinsic field-effect mobility. Thethreshold voltage also confirms a negative shift upon the molecular doping. Allstudies demonstrate the feasibility of PEI molecular doping in MoS2transistors, and its potential applications in layer-structured semiconducting2D crystals.