A comparative study of nanostructured Silicon-Nitride electrical properties for potential application in RF-MEMS capacitive switches

The present paper aims to investigate the electrical properties of nanostructured SiNx with embedded (i) CNTs of random orientation, (ii) columnar bunches of vertically aligned CNTs and (iii) columnar Au nanorods. MIM capacitors were used to assess the effect of dielectric film structure on the electrical properties. The charge transport mechanism was assessed through current - voltage characteristics and the charge draining efficiency through the top electrode potential decay. In the case of random oriented CNTs, the transport mechanisms are Frenkel-Poole and field emission at low and high electric fields respectively. In the case of Au nanorods, the hopping and Frenkel-Poole mechanisms are detected at low and high electric fields respectively. Finally, for vertically aligned CNTs the current-voltage characteristic is found to follow ohm's law. The discharge rate through the bulk material is found to depend on nanofillers morphology.