Switching Behaviors of Graphene-Boron Nitride Nanotube Heterojunctions

• Published in: Scientific reports Vol. 5; no. 1; p. 12238
• Main Authors: Parashar, Vyom, Durand, Corentin P., Hao, Boyi, Amorim, Rodrigo G., Pandey, Ravindra, Tiwari, Bishnu, Zhang, Dongyan, Liu, Yang, Li, An-Ping, Yap, Yoke Khin
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 20-07-2015; Nature Publishing Group
• Subjects: 639/925/357; 639/925/357/995; Behavior; Boron; Chemical vapor deposition; Condensed Matter; Electron microscopy; electronic properties and materials; Graphene; Humanities and Social Sciences; Laboratories; Materials Science; multidisciplinary; nanoscale materials; NANOSCIENCE AND NANOTECHNOLOGY; Nanotechnology; Nanotubes; Physics; Scanning electron microscopy; Scanning tunneling microscopy; Science; Short term memory; Spectrum analysis; Temperature effects
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep12238

High electron mobility of graphene has enabled their application in high-frequency analogue devices but their gapless nature has hindered their use in digital switches. In contrast, the structural analogous,
h-
BN sheets and BN nanotubes (BNNTs) are wide band gap insulators. Here we show that the growth of electrically insulating BNNTs on graphene can enable the use of graphene as effective digital switches. These graphene-BNNT heterojunctions were characterized at room temperature by four-probe scanning tunneling microscopy (4-probe STM) under real-time monitoring of scanning electron microscopy (SEM). A switching ratio as high as 10
5
at a turn-on voltage as low as 0.5 V were recorded. Simulation by density functional theory (DFT) suggests that mismatch of the density of states (DOS) is responsible for these novel switching behaviors.