Creation of stable nanoconstrictions in metallic thin films via progressive narrowing by focused-ion-beam technique and in situ control of resistance
This work describes the use of focused-ion-beam for the fabrication of metallic nanoconstrictions on a Fe thin film with in situ monitoring of the structures resistance. With this approach the sequential FIB steps that are used for the gradual narrowing of the nanoconstriction are observed as changes in the measured resistance, thus providing very good control of the milling process. The FIB patterning enables precise termination of the process just before the crossover between the metallic and tunneling regimes near the conductance quantum value G0 (G0=2e2/h). Compared to previous approaches to create nanoconstrictions with focused-ion-beam, this new technique determines precisely the current direction and minimizes Ga damage at the nanoconstriction.
nanoconstriction fib patterning magnetoresistive thin films conductance quantum g0