UK researchers produce high-quality atomically-thin InSe
Research reported in Nature Nanotechnology by scientists from the universities of Manchester and Nottingham, suggests that ultra-thin InSe could be used for next generation electronics.
The team has made high-quality atomically-thin films of InSe for the first time. The electron mobility at room temperature was measured at 2,000 cm2/Vs, significantly higher than silicon. This value increases several times at lower temperatures.
Andre Geim, one of the authors of this study and a recipient of the Nobel Prize in Physics for research on graphene, believes that the new findings could have a significant impact on development of future electronics.
"Ultra-thin InSe seems to offer the golden middle between silicon and graphene. Similar to graphene, InSe offers a naturally thin body, allowing scaling to the true nanometre dimensions. Similar to silicon, InSe is a very good semiconductor."
The Manchester researchers had to overcome one major problem to create high-quality InSe devices. Being so thin, InSe is rapidly damaged by oxygen and moisture present in the atmosphere. To avoid such damages, the devices were prepared in an argon atmosphere using new technologies developed at the National Graphene Institute (NGI) in Manchester.
Current experiments produced the material several micrometres in size. The researchers believe that by following the methods now widely used to produce large-area graphene sheets, InSe could also soon be produced at a commercial level.
Co-author of the paper Vladimir Falko, director of the National Graphene Institute said: "The technology that the NGI has developed for separating atomic layers of materials into high-quality 2D crystals offers great opportunities to create new material systems for optoelectronics applications. We are constantly looking for new layered materials to try."
Ultra-thin InSe is one of a growing family of 2D crystals that have a variety of useful properties depending on their structure, thickness and chemical composition.
Currently, research in graphene and related 2D materials is the fastest growing field of materials science that bridges science and engineering.
'High electron mobility, quantum Hall effect and anomalous optical response in atomically thin InSe' by Denis A. Bandurin etal; Nature Nanotechnology (DOI 10.1038/nnano.2016.242)