High-performance MoS2/p+-Si heterojunction field-effect transistors by interface modulation

Molybdenum disulfide (MoS2), one of transition metal dichalcogenides, is a promising semiconductor material for electronic or optoelectronic devices due to its favorably electronic properties. However, in metal-oxide semiconductor field-effect transistor (MOSFET) structures using MoS2, electrical performances such as mobility and subthreshold swing are suppressed by the interface trap density between the channel and dielectric layers. Moreover, the electrical stability of such structures is compromised due to interface traps and that can be analyzed such as current hysteresis and transient characteristics. Here, we demonstrate MoS2 heterojunction field-effect transistors (HFET) by applying MoS2/p(+)-Si heterojunctions and achieve high performance characteristics, including a mobility of 636.19 cm(2)/(V.s), a subthreshold swing of 67.4 mV/dec, minimal hysteresis of 0.05 V, and minimized transient characteristics. However, the HFET devices with varying the channel length demonstrated degradation of electrical performance with increasing the overlap area of the channel and dielectric layers. These results regarding MoS2/p(+)-Si HFETs resulted in the structural optimization of high-performance electronic devices for practical applications.