Strategy for reliable strain measurement in InAs/GaAs materials from high-resolution Z-contrast STEM images

Vatanparast, M., Vullum, P. E., Nord, M., Zuo, J.-M., Reenaas, T. W. and Holmestad, R. (2017) Strategy for reliable strain measurement in InAs/GaAs materials from high-resolution Z-contrast STEM images. Journal of Physics: Conference Series, 902, 012021. (doi: 10.1088/1742-6596/902/1/012021)

Abstract

Geometric phase analysis (GPA), a fast and simple Fourier space method for strain analysis, can give useful information on accumulated strain and defect propagation in multiple layers of semiconductors, including quantum dot materials. In this work, GPA has been applied to high resolution Z-contrast scanning transmission electron microscopy (STEM) images. Strain maps determined from different g vectors of these images are compared to each other, in order to analyze and assess the GPA technique in terms of accuracy. The SmartAlign tool has been used to improve the STEM image quality getting more reliable results. Strain maps from template matching as a real space approach are compared with strain maps from GPA, and it is discussed that a real space analysis is a better approach than GPA for aberration corrected STEM images.

• Item Type: Articles
• Additional Information: The Norwegian Research Council is acknowledged for funding the HighQ-IB project under contract no. 10415201.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Nord, Dr Magnus
• Authors: Vatanparast, M., Vullum, P. E., Nord, M., Zuo, J.-M., Reenaas, T. W., and Holmestad, R.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Journal of Physics: Conference Series
• Publisher: IOP Publishing
• ISSN: 1742-6588
• ISSN (Online): 1742-6596
• Published Online: 16 October 2017
• Copyright Holders: Copyright © 2017 IOP Publishing Ltd
• First Published: First published in Journal of Physics: Conference Series 902: 012021
• Publisher Policy: Reproduced under a Creative Commons License