Patent ID: 6291926
Filing Date: 2001-09-18
Classification: H03H

Abstract:
A piezoelectric resonator, comprising:a piezoelectric substrate having a substantially square shape, a first major surface and a second major surface, and vibrating in a square vibration mode;at least two electrodes each being provided on a respective one of the first major surface and the second major surface of the piezoelectric substrate; anda first plurality of grooves provided in at least one of the first major surface and the second major surface of the piezoelectric substrate, the first plurality of grooves dividing at least one of the at least two electrodes into a plurality of separate areas, the first plurality of grooves extending in two directions which are substantially perpendicular to each other, the plurality of separate areas including at least one centrally located area arranged to define an electrostatic capacitance of the resonator and to define an input-output electrode of the resonator, wherein the at least one centrally located electrode is the only input-output electrode located on said at least one of the first major surface and the second major surface of the piezoelectric substrate such that the remainder of said plurality of separate areas are not connected to a line for signal input-output and do not function as electrodes of the piezoelectric resonator.