SH surface waves in piezoelectric semiconductors loaded with a finite viscous liquid layer

This paper investigates the propagation behavior of SH surface waves in a semi-infinite n-type piezoelectric semiconductor loaded with a viscous liquid layer of finite thickness. Using the linear drift current assumption corresponding to a small electron concentration increment, the wave dispersion relations are obtained for two types of electrically boundary conditions at the solid/liquid interface. Numerical results show the effects of initial electron concentration, operating frequency and liquid properties on wave velocity and attenuation behavior, where two special examples of pure piezoelectricity and pure elasticity are also included for comparison. Particular attention is paid on the velocity variations and excessive attenuation resulted from semiconductor properties, which reflects the extent of coupling in multiphysics interactions. This study can be guidance for the future design of new acoustic wave devices.