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Publication Citation: Anisotropic Microstructure Development During the Reaction of Mg With GaAs

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Author(s): Steven W. Robey;
Title: Anisotropic Microstructure Development During the Reaction of Mg With GaAs
Published: February 18, 1998
Abstract: Reaction of Mg with GaAs (001) surface occurs at substrate temperatures above 250 K and leads to 3D growth of an epitaxial, cubic reaction phase with a lattice constant of 0.62 + 0.02nm, 9% larger than GaAs. The resulting anistotropic, 3-demiensional (3D) heteroepitaxial microstructure was studied using in situ electron diffraction and Auger spectroscopy and ex situ atomic force microscopy (AFM). 3D structures develop that are elongated alone the GaAs [110] direction with aspect ratios (length-to-width) up to 20. These structures appear to be composed of isotropic islands from which elongated, tapered ridges extend in on direction along [110]. Analysis of AFM images and size distributions suggest a critical size for the initiation of ridge formation and a discontinuous, stepwise ridge development. Potential origins of this interesting microstructure are discussed.
Citation: Journal of Vacuum Science and Technology B
Volume: 16
Pages: pp. 2413 - 2416
Keywords: AFM;GaAs;Mg;thin film reaction
Research Areas: Chemistry