Graphene-boron nitride nanotube combination creates digital switch
04 August 2015
A US research team has created digital switches by combining the conducting properties of graphene with the insulating properties of boron nitride nanotubes.
Professor Yoke Khin Yap of Michigan Technological University and his research team have created digital switches by combining graphene and boron nitride nanotubes. Their work is published in the journal, Scientific Reports. The task they faced was finding a way to fuse the two materials together by maximising their existing chemical structures and exploiting their mismatched features.
Yap and his team exfoliated graphene and modified the material's surface with tiny pinholes, through which they grew the boron nitride nanotubes. The combination forms a band gap mismatch at the junction of the materials, which can be exploited to make the digital 'on/off' switch possible.
Yap and his team have also shown that because the materials are respectively so effective at conducting and insulating, the resulting switching ratio is high. The speed at which the materials can turn on and off is several orders of magnitude greater than current graphene switches.
The problem with semiconductors like silicon is a limitation in terms of the size of component that can be created with them; they also produce a lot of heat. Graphene/boron nitride nanotube combinations avoid these problems, and since they have the same atomic arrangement pattern, or lattice matching, with their aligned atoms, graphene-nanotube digital switches would avoid the issues of electron scattering.