title: Two-dimensional lateral heterojunction through bandgap engineering of MoS2 via oxygen plasma.
abstract: The present study explores the structural, optical (photoluminescence (PL)), and electrical properties of lateral heterojunctions fabricated by selective exposure of mechanically exfoliated few layer two-dimensional (2D) molybdenum disulfide (MoS2) flakes under oxygen (O2)-plasma. Raman spectra of the plasma exposed MoS2 flakes show a significant loss in the structural quality due to lattice distortion and creation of oxygen-containing domains in comparison to the pristine part of the same flake. The PL mapping evidences the complete quenching of peak A and B consistent with a change in the exciton states of MoS2 after the plasma treatment, indicating a significant change in its band gap properties. The electrical transport measurements performed across the pristine and the plasma-exposed MoS2 flake exhibit a gate tunable current rectification behavior with a rectification ratio up to 1.3  ×  10(3) due to the band-offset at the pristine and plasma-exposed MoS2 interface. Our Raman, PL, and electrical transport data confirm the formation of an excellent lateral heterojunction in 2D MoS2 through its bandgap modulation via oxygen plasma.
authors.affiliation: NanoScience Technology Center, University of Central Florida, Orlando, FL 32816, USA.
authors.forename: Nitin
authors.initials: N
authors.lastname: Choudhary
authors.forename: Muhammad R
authors.initials: MR
authors.lastname: Islam
authors.forename: Narae
authors.initials: N
authors.lastname: Kang
authors.forename: Laurene
authors.initials: L
authors.lastname: Tetard
authors.forename: Yeonwoong
authors.initials: Y
authors.lastname: Jung
authors.forename: Saiful I
authors.initials: SI
authors.lastname: Khondaker