Carbon Nanotube-based Cold Cathode for High Power MicrowaveVacuum Electronic Devices: A Potential Field Emitter

  • P. Verma Solid State Physics Laboratory, Delhi
  • S. Gautam Solid State Physics Laboratory, Delhi
  • S. Pal Solid State Physics Laboratory, Delhi
  • P. Kumar Solid State Physics Laboratory, Delhi
  • P. Chaturvedi Solid State Physics Laboratory, Delhi
  • J.S.B.S. Rawat Solid State Physics Laboratory, Delhi
  • P. K. Chaudhary Solid State Physics Laboratory, Delhi
  • Dr. Harsh Solid State Physics Laboratory, Delhi
  • P. K. Basu Solid State Physics Laboratory, Delhi
  • P. K. Bhatanagar Delhi University, South Campus, Delhi
Keywords: Carbon nanotubes, field emission, cold cathode, microwwave vacuum electronic devices

Abstract

Carbon nanotubes (CNTs) can be grown in the form of small, sharp spikes capable of carrying very highcurrent densities which suggest great potential application of CNTs as cold cathode in high power microwavevacuum device applications. These cold cathode vacuum microwave devices are expected to be ideally suitedfor air-borne and space applications. This paper  reports the initial efforts made in the development of coldcathode using PECVD grown vertically-aligned matrix of CNTs with uniform height and optimum tip densityon silicon substrate. The high aspect ratio (of the order of 10,000) and novel electrical, mechanical, and thermalproperties of the CNT are found to be very attractive characteristics for emission of large and stable currentdensities at reasonably low field. The field emission current voltage characteristics of a typical cathode gaveemission current density in excess of 35 mA/cm2 at reasonably low field. The emission current in most of thesamples is found to be stable over long period of time but is greatly effected by the vacuum condition duringmeasurement. The initial measured data suggests great promise for achieving high current densities at practicalelectric fields.

Defence Science Journal, 2008, 58(5), pp.650-654, DOI:http://dx.doi.org/10.14429/dsj.58.1688

Published
2008-09-01
How to Cite
VermaP., GautamS., PalS., KumarP., ChaturvediP., RawatJ., ChaudharyP., HarshD., BasuP., & BhatanagarP. (2008). Carbon Nanotube-based Cold Cathode for High Power MicrowaveVacuum Electronic Devices: A Potential Field Emitter. Defence Science Journal, 58(5), 650-654. https://doi.org/10.14429/dsj.58.1688