Investigation of band-offsets at monolayer-multilayer MoS₂ junctions by scanning photocurrent microscopy.

@article{Howell2015InvestigationOB,
  title={Investigation of band-offsets at monolayer-multilayer MoS₂ junctions by scanning photocurrent microscopy.},
  author={Sarah L. Howell and Deep Jariwala and Chung-Chiang Wu and Kan Sheng Chen and Vinod Kumar Sangwan and Junmo Kang and Tobin J. Marks and Mark Christopher Hersam and Lincoln J. Lauhon},
  journal={Nano letters},
  year={2015},
  volume={15 4},
  pages={
          2278-84
        }
}
The thickness-dependent band structure of MoS2 implies that discontinuities in energy bands exist at the interface of monolayer (1L) and multilayer (ML) thin films. The characteristics of such heterojunctions are analyzed here using current versus voltage measurements, scanning photocurrent microscopy, and finite element simulations of charge carrier transport. Rectifying I-V curves are consistently observed between contacts on opposite sides of 1L/ML junctions, and a strong bias-dependent… 
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