Separating strain from composition in unit cell parameter maps obtained from aberration corrected high resolution transmission electron microscopy imaging

Journal Article · Tue Jan 21 00:00:00 EST 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4862736· OSTI ID:22275677

Schulz, T.; Remmele, T.; Korytov, M.; Markurt, T.; Albrecht, M. ^[1]; Duff, A.; Lymperakis, L.; Neugebauer, J. ^[2]; Chèze, C. ^[3]; Skierbiszewski, C. ^[3]

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1. Leibniz-Institut für Kristallzüchtung, Max-Born-Straße 2, 12489 Berlin (Germany)
2. Max-Planck-Institut für Eisenforschung, Max-Planck-Straße 1, 40237 Düsseldorf (Germany)
3. TopGaN Sp. z o.o., Sokolowska 29/37, 01-142 Warsaw (Poland)

Based on the evaluation of lattice parameter maps in aberration corrected high resolution transmission electron microscopy images, we propose a simple method that allows quantifying the composition and disorder of a semiconductor alloy at the unit cell scale with high accuracy. This is realized by considering, next to the out-of-plane, also the in-plane lattice parameter component allowing to separate the chemical composition from the strain field. Considering only the out-of-plane lattice parameter component not only yields large deviations from the true local alloy content but also carries the risk of identifying false ordering phenomena like formations of chains or platelets. Our method is demonstrated on image simulations of relaxed supercells, as well as on experimental images of an In{sub 0.20}Ga{sub 0.80}N quantum well. Principally, our approach is applicable to all epitaxially strained compounds in the form of quantum wells, free standing islands, quantum dots, or wires.

• OSTI ID: 22275677
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
77 NANOSCIENCE AND NANOTECHNOLOGY
CHEMICAL COMPOSITION
COMPUTERIZED SIMULATION
EPITAXY
GALLIUM NITRIDES
IMAGES
INDIUM COMPOUNDS
LATTICE PARAMETERS
QUANTUM DOTS
QUANTUM WELLS
SEMICONDUCTOR MATERIALS
STRAINS
TRANSMISSION ELECTRON MICROSCOPY