MOS2 FIELD-EFFECT TRANSISTORS WITH SUPERCONDUCTING SN CONTACTS

Abstract

Semiconductor MoS2 has attracted attention owing to its sizable energy band gap, significant spin-orbit coupling, and novel effects. However, the energy band gap usually gives rise to the formation of Schottky barriers at the interface to contact metal, which may render devices intended for quantum transport inapplicable at low temperature. We manifest that low temperature Ohmic contacts to mono- and few-layer MoS2 can be achieved with Tin (Sn). We propose a possible explanation: strain induced deformation of MoS2 imposed by Sn. Besides, we study the quantum transport in MoS2 benefited from the formation of transparent Sn contacts. We reveal that high bias can completely vanish weak localization, and multiple crossovers of weak localization and anti-localization which have never been reported. We discover quasi-particle tunneling and irregular resonant states in differential conductance. The characterizations demonstrate that they correlate to the superconductivity that is not from Sn but the superconducting MoS2.