We investigate the propagation of interfacial surface waves in a composite consisting
of homogeneous isotropic semiconductor halfspace coated with a thin layer of
homogeneous, transversely isotropic, piezoelectric material. The mathematical model
of the problem consists of a coupled system of partial differential equations of
motion, diffusion of electrons, and a Gauss equation along with the boundary
conditions to be satisfied at the interface and free surface of the composite
structure.
The secular equation that governs the wave propagation at the interface
has been obtained in compact form after solving the mathematical model
analytically. The secular equations in the case of stress-free, isoconcentrated and
stress-free, impermeable semiconductor halfspaces have also been deduced
as special cases. The complex secular equation has been solved using the
functional iteration method along with the irreducible Cardano’s method via
MATLAB programming for CdSe-Si, CdSe-Ge, PZT-Si and PZT-Ge composite
structures.
The computer-simulated results have been presented graphically in terms of phase
velocity, attenuation coefficient, and specific loss factor of energy dissipation versus
wave number and lifetime of charge carrier field in the considered structures. The
work may be useful for the construction and design of surface acoustic wave
devices.