ELECTRODE STRUCTURE OF SPURIOUS SUPPRESSING TYPE PIEZOELECTRIC VIBRATOR AND MONOLITHIC PIEZOELECTRIC ELEMENT FILTER

摘要

PURPOSE:To suppress a spurious response without accompanying the increase in a stage and the reduction of Q by providing and dividing the clearance with a fine width in the horizontal direction of the longitudinal direction or at a part of both outsides of both of the opposing electrode formed on a crystal substrate, and connecting the inside part electrically. CONSTITUTION:At both surfaces of an AT cutting crystal substrate 4, opposing main electrodes 5 and 5' and sub-electrodes 6, 6' and 7, 7' are formed, and the main electrode and the sub-electrode are arranged in the fine interval. Since the energy in a crystal vibrator 4 is collected to the sticking part of an electrode, and an excitation charge displacement in the closing area is expressed by a cosine curve, the electrode is divided and arranged at the prescribed interval, and then, the peak value of the charge excited to the main electrode is located at the dividing part of the electrode, the positive and negative displacement of the charge distribution in the electrically independent main electrodes 5 and 5' is cancelled and the spurious response can be removed.