Biased Surface Fluctuations due to Current Stress

Abstract

Direct correlation between temporal structural fluctuations and electron wind force is demonstrated, for the first time, by STM imaging and analysis of atomically resolved motion on a thin film surface under large applied current (10(5) A/cm2). The magnitude of the momentum transfer between current carriers and the geometrically constrained atoms in the fluctuating structure is at least 5x to 15x (+/-1sigma range) larger than for freely diffusing adatoms. Corresponding changes in surface resistivity will contribute significant fluctuation signature to nanoscale electronic properties.

Local fields in conductor surface electromigration: A first-principles study in the low-bias ballistic limit

“…18-21 When a bias is applied across a conductor, charge carriers scatter against atomic defects such as surface step edges or adatoms 4,7,22 as shown in Fig. 1.…”

“…22,33 Due to this correlation, strong external field inhomogeneities are shown to often arise within a screening length surrounding an atomic defect (as illustrated in Fig. 1) and act to drive EM.…”

“…3b. At the low local biases required to drive EM in conductors, 18,22 the non-equilibrium charge δρ e is determined by the degree to which the electrostatic potential φ H d does not follow the electrochemical potential µ d , 34 such that…”

Real-Time TEM Imaging of the Formation of Crystalline Nanoscale Gaps

“…2(a)]. This metallic adatom will experience an electron wind force [18][19][20][21], and it will be driven along the exposed high-mobility crystal plane by the applied current [ Fig. 2(b)].…”

Nonlinear Dynamics of Surface Steps

“…fusion of atoms, the direct observation of electromigration effects in real time on atomistic length scales is difficult (see, however, [10] for recent progress in this direction). In this chapter the electromigration force will be used as a conceptually simple way of driving a system of surface steps out of equilibrium, giving rise to surprisingly complex dynamical behavior.…”