Dynamics of the dauphine twins in quartz crystal up to the transition point

Abstract

The paper presents two original methods for obtaining electrical twins up to the transition point in quartz crystal: a) thermal treatment in a temperature gradient of 10–15 degree/cm at about 500°C and b) applying an electric field of 1–4kV/cm at 500°C. The twinning time dependence on the temperature, the dynamic of twin domain formation as a function of directions, thickness, temperature gradient, for +5X resonator plates are discussed. The influence of the Dauphine twins on the performances of piezoelectric resonators: resonant frequency, dynamic inductance and equivalent dynamic capacity was previously reported [1]. This paper presents the influence of twinning area on the frequency spectrum of a resonator plate of +5X-cut and the changing of the frequency-temperature characteristic when the resonator plate becomes twinned.