Nanoripple formation on GaAs (001) surface by reverse epitaxy during ion beam sputtering at elevated temperature

TL;DR

This study investigates how ion beam sputtering at high temperature induces highly ordered ripple patterns on GaAs (001) surfaces, driven by diffusion instability, independent of beam direction, revealing the role of crystal symmetry.

Contribution

It demonstrates that ripple formation on GaAs (001) surfaces during ion sputtering is governed by crystal symmetry and diffusion instability, not incident beam direction.

Findings

Ripple patterns are highly ordered and driven by diffusion instability.

Ripple orientation is determined by crystal face symmetry.

Ripple formation occurs at near normal incidence angles.

Abstract

Self-organized pattern formation by the process of reverse epitaxial growth has been investigated on GaAs (001) surfaces during 1 keV Ar+ bombardment at target temperature of 450 degC for a wide range of incident angles. Highly ordered ripple formation driven by diffusion instability is evidenced at near normal incidence angles. Concurrent sample rotation shows that the ripple morphology and its orientation do not depend on the incident beam direction; rather they are determined by the symmetry of the crystal face.