19
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: not found
      • Article: not found

      Effective Passivation of Exfoliated Black Phosphorus Transistors against Ambient Degradation

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Unencapsulated, exfoliated black phosphorus (BP) flakes are found to chemically degrade upon exposure to ambient conditions. Atomic force microscopy, electrostatic force microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy are employed to characterize the structure and chemistry of the degradation process, suggesting that O2 saturated H2O irreversibly reacts with BP to form oxidized phosphorus species. This interpretation is further supported by the observation that BP degradation occurs more rapidly on hydrophobic octadecyltrichlorosilane self-assembled monolayers and on H-Si(111) versus hydrophilic SiO2. For unencapsulated BP field-effect transistors, the ambient degradation causes large increases in threshold voltage after 6 h in ambient, followed by a ∼ 10(3) decrease in FET current on/off ratio and mobility after 48 h. Atomic layer deposited AlOx overlayers effectively suppress ambient degradation, allowing encapsulated BP FETs to maintain high on/off ratios of ∼ 10(3) and mobilities of ∼ 100 cm(2) V(-1) s(-1) for over 2 weeks in ambient conditions. This work shows that the ambient degradation of BP can be managed effectively when the flakes are sufficiently passivated. In turn, our strategy for enhancing BP environmental stability will accelerate efforts to implement BP in electronic and optoelectronic applications.

          Related collections

          Author and article information

          Journal
          Nano Letters
          Nano Lett.
          American Chemical Society (ACS)
          1530-6984
          1530-6992
          November 13 2014
          December 10 2014
          November 12 2014
          December 10 2014
          : 14
          : 12
          : 6964-6970
          Affiliations
          [1 ]Department of Materials Science and Engineering, ‡Department of Chemistry, and §Graduate Program in Applied Physics, Northwestern University, Evanston, Illinois 60208, United States
          Article
          10.1021/nl5032293
          25380142
          e9f7f058-eed0-4d32-b22b-a1339c552e10
          © 2014
          History

          Comments

          Comment on this article