From periodic monomolecular step array to macrosteps in pureand Si-doped MBE-grown GaAs on vicinal (001)surfaces

Author： Lelarge F. Wang Z. Z. Cavanna A. Laruelle F. Etienne B.

E-ISSN： 1286-4854|39|1|97-102

ISSN： 0295-5075

Source： EPL (EUROPHYSICS LETTERS), Vol.39, Iss.1, 2010-03, pp. : 97-102

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Steps and terraces on GaAs (001) vicinal surfaces misorientedtowards (111) or $(1\overline{1}1)$ are studied after MBE growth fora large range of misorientation angle ($0.2^{\circ}$ to $2^{\circ}$)using ex situ contact mode AFM. The terrace width distributionand correlation length are well explained by thermodynamicalequilibrium of interacting steps. The step-step interaction is muchlarger than in elemental materials and is dominated by dipole ratherthan elastic interaction. Step bunching is never observed on cleansurfaces for any misorientation. However, for Si-doped layers, thesurface disorder increases and formation of macrosteps occurs at veryhigh doping.