Scanning Electron Microscopy of Resonating Quartz Crystals

SL- and AT-cut quartz crystal resonators which are commonly used in frequency control devices were examined in the scanning electron microscope. The quartz slices were resonated at frequencies ranging from 455 kHz to 15 MHz. Variations in surface charges which were produced during resonance strongly affected secondary electron emission. Therefore, micrographs could be obtained which were characteristic of the various modes of motion of the resonators. From displacements of topographical features during resonance approximate values for the amplitudes of face and thickness shear were obtained.