Authors: Y. Ohno, Y. Asai, K. Maehashi, K. Inoue and K. Matsumoto
Affilation: Osaka University, Japan
Pages: 69 - 72
Keywords: carbon nanotube, field-effect transistor, single-electron transistor, Coulomb oscillation
Single-walled carbon nanotube field-effect transistors with thin tunnel barriers were investigated, and room-temperature single-electron transistor (SET) operation was realized. Single-walled carbon nanotubes were grown by thermal chemical vapor deposition at 820 degrees Celsius for 10 min using ethanol as a carbon source after forming patterned cobalt catalyst layer by conventional photolithography method. Thin tunnel barrier layer, which was oxidized 1-nm-thick aluminum layer, was inserted between nanotube channel and electrodes in order to enhance carrier confinement. Gate voltage dependences of the drain current were measured at 290 K. Clear Coulomb oscillations could be observed for the sample with tunnel barrier layer while only conventional ambipolar characteristics of conventional carbon nanotube field-effect transistors could be observed for the sample without tunnel barrier layer. These results indicate that formation of thin tunnel barrier layer is very effective for realization of SET operations at room temperature.