Fabrication of Ni quantum cross devices with a 17-nm-size junction and its current-voltage characteristics

Quantum cross (QC) devices which consist of two Ni thin films deposited on polyethylene naphthalate (PEN) substrates with their edges crossing have been fabricated and its current-voltage characteristics have been investigated. The cross-sectional area between the two Ni electrodes, which was made without the use of electron-beam or optical lithography, is as small as 17 nm x 17 nm. We have successfully obtained ohmic current-voltage characteristics, which show good agreement with calculation results within the framework of modified Anderson model. The calculated results also predict a high switching ratio in excess of 100000:1 for QC devices having the molecule sandwiched between the Ni electrodes. This indicates that QC devices having the molecule can be expected to have potential application in novel switching devices.