Vertically aligned carbon based varactors
Journal article, 2011

This paper gives an assessment of vertically aligned carbon based varactors and validates their potential for future applications. The varactors discussed here are nanoelectromechanical devices which are based on either vertically aligned carbon nanofibers or vertically aligned carbon nanotube arrays. A generic analytical model for parallel plate nanoelectromechanical varactors based on previous works is developed and is used to formulate a universal expression for their voltage-capacitance relation. Specific expressions for the nanofiber based and the nanotube based varactors are then derived separately from the generic model. This paper also provides a detailed review on the fabrication of carbon based varactors and pays special attention to the challenges in realizing such devices. Finally, the performance of the carbon based varactor is assessed in accordance with four criteria: the static capacitance, the tuning ratio, the quality factor, and the operating voltage. Although the reported performance is still far inferior to other varactor technologies, our prognosis which stems from the analytical model shows a promise of a high quality factor as well as a potential for high power handling for carbon based varactors.

Author

Farzan Alavian Ghavanini

Chalmers, Applied Physics, Electronics Material and Systems Laboratory

Peter Enoksson

Chalmers, Applied Physics, Electronics Material and Systems Laboratory

Stefan Bengtsson

Chalmers, Applied Physics, Electronics Material and Systems Laboratory

Per Lundgren

Chalmers, Applied Physics, Electronics Material and Systems Laboratory

Journal of Applied Physics

0021-8979 (ISSN) 1089-7550 (eISSN)

Vol. 110 2 021101

Areas of Advance

Transport

Production

Subject Categories

Physical Sciences

DOI

10.1063/1.3583536

More information

Created

10/8/2017