High sensitivity field emission based sensors using carbon nanotubes on silicon tip for high frequency vibration sensing

Field emission based cantilever sensor using carbon nanotubes on silicon tip was fabricated and electrical response of the device to the mechanical vibration was investigated. Plasma enhanced chemical vapor deposition was used to grow carbon nanotubes (CNTs). Field emission from nanotubes on silicon tip was realized for sensing the vibration. Exponential dependence of the field emission current to the distance between the anode and the emitter leads to a high sensitive device. The variation of the emission current during mechanical vibration of the cantilever was measured. We have obtained that frequency limit for field emission based sensors depends on the capacitance and equivalent resistance of the device. In this work we have introduced a CNT based sensor for sensing the mechanical vibration in nanometer ranges with capability of high frequency sensing. The fabricated device, due to a low distance between its electron emitters and the anode, works at low applied voltages with high emission current.

► A novel field emission based cantilever sensor was fabricated.
► Field emission was realized for sensing the displacements and vibrations.
► The fabricated device works at low applied voltages with high emission current.