Diffusion of defects and aging of quartz resonators

It is shown that diffusion of defects of a piezoelectric plate can give rise to the aging of a resonator on bulk waves which corresponds to the logarithmic law. The time limit of applicability of the logarithmic law for the aging of resonator on bulk waves as a result of diffusion processes is defined by the coefficient of diffusion, the thickness of the plate, the state of the surface layer of the plate and the quality of piezoelectric material.