Ion beam sputtering for progressive reduction of nanostructures dimensions

Abstract

An ion beam based dry etching method has been developed for progressive reduction of dimensions of prefabricated nanostructures. The method has been successfully applied to aluminum nanowires and aluminum single electron transistors (SET). The method is based on removal of material from the structures when exposed to energetic argon ions and it was shown to be applicable multiple times to the same sample. The electrical measurements and samples imaging in between the sputtering sessions clearly indicated that the dimensions, i.e. cross-section of the nanowires and area of the tunnel junctions in SET, were progressively reduced without noticeable degradation of the sample structure. We were able to reduce the effective diameter of aluminum nanowires from ∼65 nm down to ∼30 nm, whereas the tunnel junction area has been reduced by 40 %.

Thickness-Dependent Oscillations of the Critical Magnetic Field Induced by the Quantum Size Effect in Superconducting Nanofilms

“…[10], the oscillations of the critical temperature as a function of the number of atomic monolayers have been found for ultra-thin Pb films grown on Si(111) substrate. This experiment reopens an extensive research concerning the interplay of the superconductivity and the quantum confinement in nanoscale systems [1,3,11,14,18,19,22]. The study of the superconductivity in Pb nanofilms has been extended by Eom et al [8].…”

Quantum fluctuations in ultranarrow superconducting aluminum nanowires

“…1). In this work the method [21], [25] was applied to lithographically fabricated 99.999 % pure Al nanowires with initial cross-section of about 100 nm x 100 nm. During measurements the structures were immersed into a directly pumped 4 He bath with base temperature of about 0.95 K. Contrary to Refs.…”

Ion beam shaping and downsizing of nanostructures

“…single electron transistors) [5]. In all cases the technique appeared to be non-destructive enabling study of sizedependent phenomena on the same sample between the sessions of the ion beam treatment.…”