Velocity measurement of multiple leaky waves on germanium by line-focus-beam acoustic microscope using FFT

V(z) curves obtained by the acoustic line-focus beam are deformed due to multiple leaky waves. A novel velocity measurement method with FFT is developed for a V(z) curve analysis. Experiments are performed for a (111)-Ge sample and two mode spectra are separately measured corresponding to two velocities for a leaky SAW and a leaky pseudo-SAW existing on the boundary of water/sample.