Phonon-assisted carrier transport through a lattice-mismatched interface

Abstract

MoS2 typically exhibits unconventional layer-thickness-dependent electronic properties. It also exhibits layer-dependent band structures including indirect-to-direct band transitions, owing to which the electronic and carrier transport properties of a lattice-mismatched, conducting, two-dimensional junction are distinct with the naturally stepwise junction behaving as a 1D junction. We found distinguishable effects at the interface of vertically stacked MoS2. The results revealed that misorientationally stacked layers exhibited significantly low junction resistance and independent energy bandgaps without bending owing to their effectively decoupled behavior. Further, phonon-assisted carriers dominantly affected the lattice-mismatched interface owing to its low junction resistance, as determined via low-temperature measurement. Our results could facilitate the realization of high-performance MoS2 transistors with small contact resistances caused by lattice mismatching.