Direct evidences of enhanced Ga interdiffusion in InAs vertically aligned free-standing nanowires.
Direct evidences of enhanced Ga interdiffusion in InAs free-standing nanowires grown at moderate temperatures by molecular beam epitaxy on GaAs (111)B are presented in this work. Scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction measurements in coplanar and grazing incidence geometries show that nominally grown InAs NWs are actually made of an In0.86Ga0.14As alloy. Unlike typical vapor-liquid-solid growth, these nanowires are formed by diffusion-induced growth combined with strong interdiffusion from substrate material. Based on the experimental results, a simple nanowire growth model accounting for the Ga interdiffusion is also presented. This growth model could be generally applicable to the molecular beam heteroepitaxy of III-V nanowires.
González
J C
JC
Departamento de Física, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Postal Code 702, 30123-970 Belo Horizonte, Brazil.
Malachias
A
A
Andrade
R-Ribeiro
RR
de Sousa
J C
JC
Moreira
M V B
MV
de Oliveira
A G
AG