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Title: Binary-collision modeling of ion-induced stress relaxation in cubic BN and amorphous C thin films

Abstract

It is demonstrated that ion-bombardment-induced stress release during physical vapor deposition of cubic boron nitride (cBN) and amorphous carbon (aC) films is related to collisional relocation of atoms. A model based on TRIM and molecular dynamics computer simulations is presented. Experimental results obtained using pulsed substrate bias are in good agreement with the model predictions at adequately chosen threshold energies of atomic relocation. The collisional relaxation model describes the experimental data significantly better than the widely applied thermal spike model.

Authors:
; ; ;  [1];  [2]
  1. Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, D-01314 (Germany)
  2. (Australia)
Publication Date:
OSTI Identifier:
20971898
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 18; Other Information: DOI: 10.1063/1.2734472; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMORPHOUS STATE; BORON NITRIDES; CARBON; COMPUTERIZED SIMULATION; EXPERIMENTAL DATA; ION BEAMS; MOLECULAR DYNAMICS METHOD; PHYSICAL VAPOR DEPOSITION; SEMICONDUCTOR MATERIALS; STRESS RELAXATION; STRESSES; SUBSTRATES; THERMAL SPIKES; THIN FILMS; THRESHOLD ENERGY

Citation Formats

Abendroth, B., Jaeger, H. U., Moeller, W., Bilek, M., and Applied and Plasma Physics Department, School of Physics, University of Sydney, Sydney, New South Wales 2006. Binary-collision modeling of ion-induced stress relaxation in cubic BN and amorphous C thin films. United States: N. p., 2007. Web. doi:10.1063/1.2734472.
Abendroth, B., Jaeger, H. U., Moeller, W., Bilek, M., & Applied and Plasma Physics Department, School of Physics, University of Sydney, Sydney, New South Wales 2006. Binary-collision modeling of ion-induced stress relaxation in cubic BN and amorphous C thin films. United States. doi:10.1063/1.2734472.
Abendroth, B., Jaeger, H. U., Moeller, W., Bilek, M., and Applied and Plasma Physics Department, School of Physics, University of Sydney, Sydney, New South Wales 2006. Mon . "Binary-collision modeling of ion-induced stress relaxation in cubic BN and amorphous C thin films". United States. doi:10.1063/1.2734472.
@article{osti_20971898,
title = {Binary-collision modeling of ion-induced stress relaxation in cubic BN and amorphous C thin films},
author = {Abendroth, B. and Jaeger, H. U. and Moeller, W. and Bilek, M. and Applied and Plasma Physics Department, School of Physics, University of Sydney, Sydney, New South Wales 2006},
abstractNote = {It is demonstrated that ion-bombardment-induced stress release during physical vapor deposition of cubic boron nitride (cBN) and amorphous carbon (aC) films is related to collisional relocation of atoms. A model based on TRIM and molecular dynamics computer simulations is presented. Experimental results obtained using pulsed substrate bias are in good agreement with the model predictions at adequately chosen threshold energies of atomic relocation. The collisional relaxation model describes the experimental data significantly better than the widely applied thermal spike model.},
doi = {10.1063/1.2734472},
journal = {Applied Physics Letters},
number = 18,
volume = 90,
place = {United States},
year = {Mon Apr 30 00:00:00 EDT 2007},
month = {Mon Apr 30 00:00:00 EDT 2007}
}
  • No abstract prepared.
  • The bonding structure of cubic boron nitride (cBN) films with different levels of intrinsic stress (1-10 GPa) has been studied from the K-shell x-ray absorption near-edge structure (XANES). The stress level was tuned by the damage induced from simultaneous medium-energy ion implantation (1-10 keV) during growth. The films show a dominant sp{sup 3} arrangement for damage values below a certain threshold, with an appreciable sp{sup 3} to sp{sup 2} transformation taking place above this limit. Interestingly, the degree of stress in sp{sup 3} structures is reflected in the B 1s spectral line shape, which progressively converges to that of stress-freemore » cBN powder for increasing ion damage. These results indicate that stress buildup and release occur at a microscopic level. The changes in the spectral line shape are correlated with modifications in the electronic structure due to the presence of intrinsic stress and bond distortion within the cubic network, as predicted by density functional theory calculations. Our findings reveal the potential of XANES spectroscopy to detect stress in disordered BN systems.« less
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