Low fluctuation and drift of field emission currents emitted from Pd/W nanotips

Abstract

The authors have observed the fluctuation and drift of field emission ͑FE͒ current from nanotips fabricated by the deposition of Pd under extreme high vacuum and subsequent annealing at ϳ1000 K. Observed fluctuations of 0.02%-1% for 100 h at ϳ10 nA were extremely low when compared with those of conventional FE guns ͑a few percent͒. From a practical point of view, drifts in FE current were negligible over several hours. When the Pd layer had been removed by repeated heating and FE operation, Pd redeposition on the tip apex was necessary for their restoration.

Thermal Stability of Single-Atom Termination at a Pyramidal Apex of an Ir-W Tip

“…In fact, the SAT tip of Pd-W showed extremely low fluctuation, less than 1% at 1 nA in the initial stage of reconstruction and slight fluctuation, a few % after 500-h operation [4]. Similar quantitative study is expected for the SAT tip of Ir-W, but not yet.…”

Optical and electrical properties of functional materials at the nanoscale

“…Up to now, we have established a qualitative connection between the electrical charge surface gradient. Electric current behaviour and instabilities in either amorphous or crystalline semiconductors are previously assigned to interfacial inhomogeneities [13], mechanical fluctuations [14]- [16], electric field stressing [17], [18], internal feedback and charge trapping [19]- [21], different fabrication techniques [22], [23], electron tunneling and confinement [24], surface treatments [25], atomic rearrangement in conductive junctions [26], degradation [27], local electron valence structures [28], morphologies [29], [30], sensitivities [31] and contamination [32]. In addition, significant work that connects surface morphological characteristics and current instabilities in crystalline solids was published previously by Maroudas et al, [29], [33].…”