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Title: Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength

Abstract

In this work, we report on correlations between surface density variations and ion parameters during ion beam-induced surface patterning process. The near-surface density variations of irradiated Si(100) surfaces were investigated after off-normal irradiation with 5 keV Fe ions at different fluences. In order to reduce the x-ray probing depth to a thickness below 5 nm, the extremely asymmetrical x-ray diffraction by variation of wavelength was applied, exploiting x-ray refraction at the air-sample interface. Depth profiling was achieved by measuring x-ray rocking curves as function of varying wavelengths providing incidence angles down to 0°. The density variation was extracted from the deviations from kinematical Bragg angle at grazing incidence angles due to refraction of the x-ray beam at the air-sample interface. The simulations based on the dynamical theory of x-ray diffraction revealed that while a net near-surface density decreases with increasing ion fluence which is accompanied by surface patterning, there is a certain threshold of ion fluence to surface density modulation. Our finding suggests that the surface density variation can be relevant with the mechanism of pattern formation.

Authors:
;  [1];  [2];  [3]
  1. Solid State Physics, University of Siegen, D-57068 Siegen (Germany)
  2. Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden (Germany)
  3. Synchrotron Light Source ANKA, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)
Publication Date:
OSTI Identifier:
22350974
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 16; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ASYMMETRY; BRAGG REFLECTION; CORRELATIONS; DENSITY; DEPTH; INTERFACES; ION BEAMS; IRON IONS; IRRADIATION; KEV RANGE 01-10; MODULATION; REFRACTION; SILICON; SIMULATION; SPATIAL DISTRIBUTION; SURFACES; THICKNESS; WAVELENGTHS; X RADIATION; X-RAY DIFFRACTION

Citation Formats

Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de, Pietsch, U., Facsko, S., and Doyle, S.. Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength. United States: N. p., 2014. Web. doi:10.1063/1.4899068.
Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de, Pietsch, U., Facsko, S., & Doyle, S.. Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength. United States. doi:10.1063/1.4899068.
Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de, Pietsch, U., Facsko, S., and Doyle, S.. Mon . "Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength". United States. doi:10.1063/1.4899068.
@article{osti_22350974,
title = {Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength},
author = {Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de and Pietsch, U. and Facsko, S. and Doyle, S.},
abstractNote = {In this work, we report on correlations between surface density variations and ion parameters during ion beam-induced surface patterning process. The near-surface density variations of irradiated Si(100) surfaces were investigated after off-normal irradiation with 5 keV Fe ions at different fluences. In order to reduce the x-ray probing depth to a thickness below 5 nm, the extremely asymmetrical x-ray diffraction by variation of wavelength was applied, exploiting x-ray refraction at the air-sample interface. Depth profiling was achieved by measuring x-ray rocking curves as function of varying wavelengths providing incidence angles down to 0°. The density variation was extracted from the deviations from kinematical Bragg angle at grazing incidence angles due to refraction of the x-ray beam at the air-sample interface. The simulations based on the dynamical theory of x-ray diffraction revealed that while a net near-surface density decreases with increasing ion fluence which is accompanied by surface patterning, there is a certain threshold of ion fluence to surface density modulation. Our finding suggests that the surface density variation can be relevant with the mechanism of pattern formation.},
doi = {10.1063/1.4899068},
journal = {Applied Physics Letters},
number = 16,
volume = 105,
place = {United States},
year = {Mon Oct 20 00:00:00 EDT 2014},
month = {Mon Oct 20 00:00:00 EDT 2014}
}
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