Studies by x-ray topography of the mass-loading effect on quartz and langasite resonator parameters

In this paper the results of electrical measurements of the mass-loading influence on AT-cut quartz and Y-cut langasite resonators are compared with those obtained by X-ray topography analysis of the same resonators. The mass-loading effects on resonator characteristics have been studied using the Ballato´s transmission-line analogs of the trapped-energy resonators vibrating in thickness-shear mode. This study revealed that the mass-loading influence on electrical parameters of langasite resonators is smaller than in the case of quartz resonators. 5MHz Sawyer AT-cut quartz and Y-cut langasite resonators with Au electrodes, having various diameters and thicknesses were used in experiments. The results of the X-ray topography investigations are in agreement with the electrical measurements previously performed.