Nanotube and nanowire transistors

In this paper we report the use of in-situ grown single wall carbon nanotubes (SWCNTs) from pre-patterned catalyst islands to construct nanotube electronics. The SWCNTs were grown via thermal chemical vapour deposition (CVD) on catalysts islands which were prepared by sputtering, initially, alignment marks are patterned simultaneously with the catalysts islands to enable accurate overlay of contact patterns during the top down fabrication approach for SWCNT devices. The gate transfer characteristics of p-channel SWCNTs are presented. The use of pre-patterned catalyst islands allows control of the SWCNT location required for integrated circuits. Characteristics of ZnO nanowire transistors are also introduced. Very high mobilities are measured in n-channel devices in which the gate is defined in a self aligned manner to have a nanoscale air-gap insulator. The characteristics of the ZnO transistor are comparable to those of achieved from SWCNTs. This raises the possibility of using SWCNTs for p-channel and ZnO nanowires for n-channel in complimentary switching devices.