Share Email Print

Proceedings Paper

Measurement of elastic properties of thin films by surface Brillouin scattering
Author(s): Marco Giuseppe Beghi; Carlo E. Bottani; Rosanna Pastorelli
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Elastic properties of thin supported films can be derived from the dispersion relations of surface acoustic waves (SAWs), which depend on the properties of the films themselves. Among the techniques for the measurement of SAW velocities surface Brillouin scattering (SBS) of visible light probes SAWs at the shorter wavelengths (around 0.5 micrometers ), allowing resolution down to nanometric films. Since SAW velocities can be computed as function of elastic constants and mass density of both the film and the substrate, of film thickness and of wavevector, the elastic properties can be obtained by fitting the computed velocities of the measured ones. Namely, if film thickness and density are independently measured, e.g. by X-ray reflectivity and X-ray diffraction, the elastic constants of the film can be derived by a Generalized Least Squares estimator, with corresponding confidence intervals. Accurate derivation of elastic constants requires highly accurate SAW velocity measurements. Some examples are considered in detail: diamond-like carbon films on silicon substrate and titanium silicide films, showing that elastic constants of thin films can be determined by SBS measurements with precisions ranging from reasonable to very good.

Paper Details

Date Published: 29 September 2000
PDF: 12 pages
Proc. SPIE 4098, Optical Devices and Diagnostics in Materials Science, (29 September 2000); doi: 10.1117/12.401637
Show Author Affiliations
Marco Giuseppe Beghi, INFM and Politecnico di Milano (Italy)
Carlo E. Bottani, INFM and Politecnico di Milano (Italy)
Rosanna Pastorelli, INFM and Politecnico di Milano (Italy)

Published in SPIE Proceedings Vol. 4098:
Optical Devices and Diagnostics in Materials Science
David L. Andrews; David L. Andrews; Toshimitsu Asakura; Suganda Jutamulia; Wiley P. Kirk; Max G. Lagally; Ravindra B. Lal; James D. Trolinger, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?