We report the fabrication of field-emission devices based on vertically aligned carbon nanotubes that possess a novel gate structure with applications in flat-panel displays, nanolithography systems and new sensor technologies. The devices consist of CNTs grown by PECVD on Si substrates and then coated with layers of TiO2 and chromium. Subsequently, the structures are polished in order to expose the CNT and oxygen-plasma treated to clean the surfaces. When a plate is placed parallel to the CNT structures and a voltage is applied between this plate (anode) and the silicon substrate (cathode), field emission of electrons from the CNT occurs and a current can be measured. The I-V characteristics of the device have been recorded and their operation was in many ways analogous to that of a field-effect transistor. A model based on classical electromagnetic and Fowler-Nordheim theory has been developed to better understand the operation of these devices. Excellent agreement between theory and experimentally emitted current as a function of gate potential was observed.
Journal: TechConnect Briefs
Volume: 1, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 1
Published: May 20, 2007
Pages: 5 - 8
Industry sector: Advanced Materials & Manufacturing
Topics: Carbon Nano Structures & Devices