Abstract
We present the formation of intermolecular nanotube junctions and investigations of their transistor behavior. T-shape junctions were formed by coupling chemically functionalized nanotubes with molecular linkers. An end-to-side or end-to-end heterojunction can be formed by reacting chloride terminated nanotubes with aliphatic diamine. The chemically modified nanotube mats were characterized by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The incorporation of functional groups into nanotubes are first identified by XPS. The carbon binding energy shifts due to the doping effect by attached functional groups. This also leads to a pronounced shift of tangential vibration modes in Raman spectra. To investigate the electrical transport, functionalized nanotubes were deposited on Si substrates, and metal contacts were applied on top of the selected T-shape junctions. The bar of the ""T"" is used as a transistor channel and the leg of the ""T"" is used as a gate. In this configuration, the active area is confined to a few nanometers in all three dimensions and gain values of 100 and above are obtained.