Direct measurement of surface acoustic wave velocities and accuracy enhancement by wavelet transform

The aim of this work is to show that the wavelet transform as an image processing technique has the capability to improve quantitative measurements of surface acoustic wave (SAW) velocities. An outline of the basic properties of the wavelet transform and its advantages is given. We apply the wavelet transform to a recently developed measurement technique for the determination of SAW velocities. This technique is based on a modified scanning acoustic microscope (SAM) and can be thought as directly imaging SAWs that propagate on the surface of a solid. Results for the SAW velocity of silicon single crystals are presented.