Pressure sensitivity of Rayleigh and Sezawa wave in ZnO/Si[001] structures

In this study we investigate the pressure effect on the guided waves in ZnO/Si[001] structures. Our experimental results reveal a strong dependence of the pressure sensitivities on the depth penetration of the waves. This dependence is explained by studying the effect of layer thickness and wavelength on the pressure sensitivity of Sezawa and Rayleigh wave. The measured results shows that strain compensation can be achieved in ZnO/Si structure. A theoretical results obtained by considering strain effect in silicon substrate alone are compared with measurements and show a good agreement in the case of Sezawa wave. Concerning the Rayleigh wave, the ZnO film effect should be taken in consideration in theoretical formulation.