Fabrication of Room-Temperature Operational Single-Electron Devices Using Au Nanoparticles

Au nanoparticles (5-10 nm in diameter) single electron devices (SEDs) were fabricated utilizing both electron beam lithography and granular film deposition. Both multiple-tunnel junction (MTJ) and double-tunnel junction (DTJ) were fabricated by adjusting the number of Au nanoparticles between the electrodes. Coulomb blockade effects were clearly observed at room temperature from the MTJs. The threshold voltage of the MTJ-SED with a large gap was about 1.5 V, whereas that with a small gap was about 0.8 V, respectively. When the gap was below 20 nm, a periodic Coulomb staircase was observed from the DTJ-SED at room temperature, where the charging energy was about 0.114 eV.