Coulomb blockade effects at room temperature in thin-film nanoconstrictions fabricated by a novel technique

A technique was developed to fabricate and probe nanosize tunneling structu res in thin metallic films. Using oblique evaporation through conventional undercut electron-beam lithographic masks, as the sample resistance was mea sured in situ, we defined constrictions with widths and lengths of about 10 nm in thin granular palladium films. The tunneling conductivity through a network of metallic grains was studied. Single electron tunneling transisto r effects were registered. An electrostatic gate voltage at room temperatur e could clearly modulate Coulomb blockade offsets of the order of 0.1 V in the current-voltage curves. (C) 1998 American Institute of Physics. [S0003- 6951(98)02250-5].