Abstract

Dr Matthew T. Cole is is a Research Fellow at Cambridge University investigating the heterogeneous integration of chemical vapour deposited aligned nanomaterials in nanoscale vacuum electronics devices. He is based in the Electrical Engineering Division of the Department of Engineering and is a member of the Centre for Advanced Photonics and Electronics, the Cambridge Graphene Centre, and the Electronic Devices & Materials group.

Graphene and carbon nanotubes have dominated various technology roadmaps of late. Their unique physical properties lend themselves to high advanced composite and novel electronic systems, though is the apparent hype justified? This talk will give a brief introduction to nanotechnology followed by an overview of the means and merits of the various growth and isolation methods discussed. By way of an example, the second part of the talk will focus on a single application to assess the functional merits of the nanocarbons; namely for the realisation of ultra-precision engineered near atom scale electron guns. Graphitic nano-carbons out-perform conventional metallic Spindt-like electron emitters across virtually all standardised metrics. Carbon nanotubes (CNT) and graphene offer high-aspect ratios, chemical inertness, near instantaneous temporal response and low sputter cross-sections, all of which contribute to their advantageously low turn-on fields, negligible hysteresis and high temporal stability. Nevertheless, the efficient use of these emerging nanomaterials in travelling wave tubes, parallel electron beam lithography systems, microwave amplifiers, thin film displays and X-ray sources requires the ability to define, with high fidelity and reproducibility, sub-micron-scale periodic features. This presentation will present work on the growth, characterisation and integration of chemical vapour deposited carbon nanotubes and graphene to form various unique electron sources including; nanoscale fins, low-cost emitters on catalytically activated metal mesh, silicon-on-insulator ballasted CNT arrays, high electron transparent graphene triodes, and the first large-area graphene-based electron emission display.