Patterned nano-sized gold dots within FET channel: from fabrication to alignment of single walled carbon nanotube networks

Abstract

We have introduced patterned gold dots between the electrodes of single walled carbon nanotube (SWNT) network films, to effectively guide the path of randomly assembled nanotube networks. Direct visualization results show well-aligned SWNT networks across the gold dots, generating improved SWNT–FET performance with a high on/off ratio of 10⁴ and 85 cm² V⁻¹s⁻¹ mobility, a remarkable enhancement compared to SWNT–FET in the absence of patterned gold dots. Unlike previously reported alignment techniques used, the proposed method affords the selective alignment of SWNTs within electrodes at room temperature without any direct growth on the device surface, and without the need for further alignment procedures. Thus, this gold-dot pattern technique within FET channel has proven to be truly simple, reliable and cost-effective. We discuss the effect of the voltage, channel size and feature dimensions of the gold nanopatterns in field effect transistor (FET) structures.