Publication Type
Journal
Journal Name
Ultramicroscopy
Publication Date
Page Numbers
172 to 176
Volume
109
Issue
2
Abstract
A phenomenological method is developed to determine the composition of materials, with atomic column resolution, by analysis of integrated intensities of aberration-corrected Z-contrast scanning transmission electron microscopy images. The method is exemplified for InAsxP1-x alloys using epitaxial thin films with calibrated compositions as standards. Using this approach we have determined the composition of the two-dimensional wetting layer formed between self-assembled InAs quantum wires on InP (001) substrates. The method utilizes a series of B coefficients that models the background signal in Z-contrast images, which is unaccounted for by image simulations.