Researchers at the University of California, Los Angeles, have succeeded in minimizing both the contact resistance and channel length in transistors made from the 2D semiconductor molybdenum disulphide, so making a device that has a high ON current of 0.83 mA/µm at 300K. This new work shows for the first time that 2D semiconducting transistors can compete with silicon-based ones in terms of performance – as defined by the International Technology Roadmap for Semiconductors (ITRS).
Molybdenum disulphide (MoS2) belongs to the family of single-layer transition metal dichalcogenides (TMDs). These are quasi-two-dimensional materials with the chemical formula MX2, consisting of an atomic plane of a transition metal M (Ti, Nb, Mo, Re) sandwiched between the atomic planes of a chalcogen X (S, Se or Te). These materials go from being indirect bandgap semiconductors in the bulk to direct bandgap semiconductors when scaled down to monolayer thickness. These monolayers efficiently absorb and emit light and so might find use in a variety of electronics and optoelectronics device applications.