Open AccessDevelopment of a high frequency ultrasonic setup for measuring the parameters of thin films
Author(s) -
P. S. Martyanov,
Pavel V. Zinin,
С. А. Титов
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2127/1/012057
Subject(s) - materials science , ultrasonic sensor , optics , laser , thin film , absorption (acoustics) , nanosecond , acoustic wave , displacement (psychology) , acoustics , optoelectronics , composite material , nanotechnology , physics , psychology , psychotherapist
In this report a novel method for measuring the elastic properties of thin 10 nm films is described. The method is based on the use of a nanosecond laser for generation acoustic waves in solids. Absorption of the incident laser pulse energy and the associated temperature gradients induces a rapidly changing strain field. This strain field, in turn, radiates energy as elastic (ultrasonic) waves. At low pulse power, this is an entirely thermo elastic process resulting in no damage to the sample. The acoustic echo arriving at the probed surface causes both the displacement of the surface (a few nanometres) and the strain in the subsurface material, which might be detected through the variation of the optical reflectivity of the material, i.e. through the acousto-optic effect.