Transport properties of superconducting amorphous W-based nanowires fabricated by focused-ion-beam-induced-deposition for applications in Nanotechnology

Abstract

We report transport measurements of superconducting amorphous W-based nanodeposits fabricated by focused-ion-beam-induced-deposition (FIBID) technique using W(CO)6 as the gas precursor. We have found that nanowires with width down to ˜100 nm can be grown by FIBID, maintaining the relatively high TC of �5.2 K shown by wider nanodeposits. The critical current found in these nanowires is in the range of 0.8 mA/?m2 at 2 K. At that temperature the critical field HC2 is found to be ?8 T. As previously shown by STM measurements [I. Guillam�n et al., New Journal of Physics 10, 093005 (2008)], these nanodeposits closely follow the BCS theory and are very stable under ambient conditions. All these features pave the way for a wide range of applications of these FIBID W-based nanowires in the field of Nanotechnology.

Identifying the crossover between growth regimes via in-situ conductance measurements in focused electron beam induced deposition

“…At this point it is worth mentioning that the conductivity can be further increased by employing focused ion beam induced deposition (FIBID) in combination with the precursor W(CO) 6 . Metallic tungsten-based FIBID structures which are also known to become superconducting below 5.2 K, [34][35][36][37] exhibit conductivity values up to 400-680 kS/m exceeding the values for tungsten-based FEBID structures reported here by a factor of 30-50 [34,36,38]. The difference of conductivity between samples prepared by means of FEBID and FIBID is, however, not inherent to deposits fabricated by the dissociation of W(CO) 6 .…”

Lateral resolution in focused electron beam-induced deposition: scaling laws for pulsed and static exposure

“…In such a way, local functional nanostructures can be formed without multistep processing, which is necessary in common resistbased electron beam lithography. Among the functional materials that have been fabricated using FEBID are ferromagnetic wires [2][3][4], metallic [5], and graphitic material [6] for low-resistance nanocontacts, as well as granular wires for strain sensors [7], magnetic sensors [8], gas sensors [9], and material with photonic/plasmonic functionality [10][11][12][13].…”

Nanoscale Electrical Contacts Grown by Focused Ion Beam (FIB)-Induced Deposition

“…An SEM image with the four aluminium pads used for four-point measurements is shown in the inset , where the scale bar is 10 μm. Reprinted from [ 44 ] Apart from making contacts to nano-objects, which will be widely discussed in the following sections, W FIBID superconducting deposits have recently found additional applications. For example, basic studies of the behaviour of the superconducting vortex lattice as a function of magnetic fi eld and temperature have been carried out [ 42 , 50 , 51 ].…”