We present the first application of a novel noncontact velocity measurement method of surface acoustic waves (SAW) to evaluation of thin films. This method uses laser interference fringes scanned at the phase velocity of SAW. The scanning interference fringes (SIF) are produced by intersecting two laser beams with a frequency difference. It was found that the Si3N4 film prepared by the low pressure CVD had similar elastic property to that of a sintered body. The dispersive Sezawa waves on the flame hydrolysis deposited SiO2 films on Si (100) surface were detected. Comparing the measured Sezawa wave velocity with calculated velocity, the films were found to be remarkably softer than a bulk SiO2 (fused quartz).
|Number of pages||4|
|Journal||Proceedings of the IEEE Ultrasonics Symposium|
|Publication status||Published - 1994|
|Event||Proceedings of the 1994 IEEE Ultrasonics Symposium. Part 1 (of 3) - Cannes, Fr|
Duration: 1994 Nov 1 → 1994 Nov 4
ASJC Scopus subject areas
- Acoustics and Ultrasonics