Current-Induced Step Bending Instability on Vicinal Surfaces

TL;DR

This paper models a new linear instability caused by current-induced effects on vicinal Si(111) surfaces, revealing novel step patterns through a generalized 2D BCF model and Monte Carlo simulations.

Contribution

It introduces a generalized 2D BCF model incorporating diffusion bias and attachment barriers, explaining observed step bunching phenomena.

Findings

Identification of a new linear instability mechanism

Prediction of novel step patterns

Validation through Monte Carlo simulations

Abstract

We model an apparent instability seen in recent experiments on current induced step bunching on Si(111) surfaces using a generalized 2D BCF model, where adatoms have a diffusion bias parallel to the step edges and there is an attachment barrier at the step edge. We find a new linear instability with novel step patterns. Monte Carlo simulations on a solid-on-solid model are used to study the instability beyond the linear regime.