Electromigration and potentiometry measurements of single-crystalline Ag nanowires under UHV conditions

Abstract

We report on in situ electromigration and potentiometry measurements on single-crystalline Ag nanowires under ultra-high vacuum (UHV) conditions, using a four-probe scanning tunnelling microscope (STM). The Ag nanowires are grown in place by self-organization on a 4° vicinal Si(001) surface. Two of the four available STM tips are used to contact the nanowire. The positioning of the tips is controlled by a scanning electron microscope (SEM). Potentiometry measurements on an Ag nanowire were carried out using a third tip to determine the resistance per length. During electromigration measurements current densities of up to 1 × 10(8) A cm(-2) could be achieved. We use artificially created notches in the wire to initiate electromigration and to control the location of the electromigration process. At the position of the notch, electromigration sets in and is observed quasi-continuously by the SEM.

<i>In Situ </i>Microfabrication and Measurements of Bi₂Se₃Ultrathin Films in a Multichamber System with a Focused Ion Beam, Molecular Beam Epitaxy, and Four-Tip Scanning Tunneling Microscope

“…The resistance is proportional to the length L of the measured portion, with different gradients depending on the wire width and the existence of the Se-capping layer. Similar results were obtained in the previous four-point probe measurement of nanowires of different materials self-assembled on Si surfaces [24,29,30]. The data in Fig.…”

“…The tip-contact pads are for avoiding possible damage of the wire by the direct contact of tips (as reported in Ref. 24).…”

Electron-induced limitation of surface plasmon propagation in silver nanowires

“…For all investigated Ag nanowires, electrical failure occurs at the positive electrode (point 1). This behavior, already reported for another type of crystalline Ag nanowires [48,49], suggests that the breakage originates from a motion of charged atoms initiated by the electric field present across the nanowire. However, Fig.…”

“…2(b) indicates the collection limit due to the objective numerical aperture |k x /k o |=1. 49. The inner boundary corresponds to critical angle of the glass/air interface at |k x /k o |=1.0.…”

Electromigration and the structure of metallic nanocontacts

“…A further development of the technique is to use four STM tips and to contact a structure on the surface using these four tips (Homoth et al, 2009;Kaspers et al, 2009;Okino et al, 2005;and Lin et al, 2004). The main challenge here is to avoid thermal oscillations of the relatively long and thin metallic tips.…”