Tunable Transport Gap in Phosphorene

In this article, we experimentally demonstrate that the transport gap of phosphorene can be tuned monotonically from ∼0.3 to ∼1.0 eV when the flake thickness is scaled down from bulk to a single layer. As a consequence, the ON current, the OFF current, and the current ON/OFF ratios of phosphorene field effect transistors (FETs) were found to be significantly impacted by the layer thickness. The transport gap was determined from the transfer characteristics of phosphorene FETs using a robust technique that has not been reported before. The detailed mathematical model is also provided. By scaling the thickness of the gate oxide, we were also able to demonstrate enhanced ambipolar conduction in monolayer and few…

• UD
  U.S. Department of Energy

  Awards: AC02-06CH11357, DE-AC02, 06CH11357, DE-AC02-06CH11357, DE-AC02-
• OO
  Office of Science

  Awards: DE-AC02-06CH11357, DE-AC02, 06CH11357, AC02-06CH11357
• BE
  Basic Energy Sciences

  Awards: DE-AC02, AC02-06CH11357, 06CH11357
• HE
  High Energy Physics

  Award: DE-AC02-06CH11357