Tuning Electrical Conductance of MoS2Monolayers through Substitutional Doping

Hui Gao, Joonki Suh, Michael C. Cao, Andrew Y. Joe, Fauzia Mujid, Kan Heng Lee, Saien Xie, Preeti Poddar, Jae Ung Lee, Kibum Kang, Philip Kim, David A. Muller, Jiwoong Park

Research output: Contribution to journalArticlepeer-review

70 Scopus citations

Abstract

Tuning electrical conductivity of semiconducting materials through substitutional doping is crucial for fabricating functional devices. This, however, has not been fully realized in two-dimensional (2D) materials due to the difficulty of homogeneously controlling the dopant concentrations and the lack of systematic study of the net impact of substitutional dopants separate from that of the unintentional doping from the device fabrication processes. Here, we grow wafer-scale, continuous MoS2 monolayers with tunable concentrations of Nb and Re and fabricate devices using a polymer-free approach to study the direct electrical impact of substitutional dopants in MoS2 monolayers. In particular, the electrical conductivity of Nb doped MoS2 in the absence of electrostatic gating is reproducibly tuned over 7 orders of magnitude by controlling the Nb concentration. Our study further indicates that the dopant carriers do not fully ionize in the 2D limit, unlike in their three-dimensional analogues, which is explained by weaker charge screening and impurity band conduction. Moreover, we show that the dopants are stable, which enables the doped films to be processed as independent building blocks that can be used as electrodes for functional circuitry.

Original languageEnglish (US)
Pages (from-to)4095-4101
Number of pages7
JournalNano Letters
Volume20
Issue number6
DOIs
StatePublished - Jun 10 2020
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Keywords

  • Doping
  • impurity conduction
  • metal-organic chemical vapor deposition
  • molybdenum disulfide
  • two-dimensional materials

Fingerprint

Dive into the research topics of 'Tuning Electrical Conductance of MoS2Monolayers through Substitutional Doping'. Together they form a unique fingerprint.

Cite this