Dynamic study of a field emission sensor based on carbon nanotubes for acceleration and high frequency vibration sensing

Nano-Physics Research Laboratory, Department of Physics, University of Tehran, Tehran, Iran

^a e-mail: arzi@khayam.ut.ac.ir

Received: 10 January 2011
Accepted: 16 May 2011
Published online: 21 July 2011

Abstract

Plasma enhanced chemical vapor deposition was used to grow vertically aligned carbon nanotubes (CNTs) on silicon substrate. Field emission from these nanotubes was realized and used to fabricate a field emission-based sensor. Titanium dioxide was used as spacing layer between the emitters and a flexible anode made of silicon membrane. The variation of the emission current during mechanical vibration of the silicon membrane was measured and compared with a theoretical prediction. Experimental results show that field emission from CNTs is a good candidate for high frequency vibration sensing, measurement of resonance frequency, fabrication of accelerometer and other types of mechanical sensors. The fabricated device, due to a low distance between its electron emitters and the anode, works at low voltages with high emission current.