PIEZOELECTRIC VIBRATION ELEMENT, PIEZOELECTRIC VIBRATOR, PIEZOELECTRIC OSCILLATOR, AND ELECTRONIC DEVICE

摘要

A piezoelectric vibration element includes a piezoelectric substrate including (i) an excitation portion and (ii) a peripheral portion that is integrally arranged at a periphery of the excitation portion and whose thickness is smaller than that of the excitation portion. The piezoelectric vibration element further includes excitation electrodes that are arranged in a front-and-rear relationship on front and rear principal faces of the piezoelectric substrate. The excitation portion includes a first portion that is at a location of a maximum thickness of the excitation portion and a side face that is connected to (i) a principal face of the first portion and (ii) a principal face of the peripheral portion. The side face includes level difference portions having a level difference and a face that has no level difference from the principal face of the first portion to the principal face of the peripheral portion.

主权项

1. A piezoelectric vibration element comprising:
a piezoelectric substrate including (i) an excitation portion and (ii) a peripheral portion that is integrally arranged at a periphery of the excitation portion and whose thickness is smaller than that of the excitation portion; and excitation electrodes that are arranged in a front-and-rear relationship on front and rear principal faces of the piezoelectric substrate;
the excitation portion including:
a first portion that is at a location of a maximum thickness of the excitation portion; anda side face that is connected to (i) a principal face of the first portion and (ii) a principal face of the peripheral portion;the side face including:
level difference portions having a level difference; anda face that has no level difference from the principal face of the first portion to the principal face of the peripheral portion, wherein the level difference portions are arranged at two locations sandwiching the first portion therebetween, with the principal faces seen in plan view; the face that has no level difference extends along a direction in which the two positions are aligned, and is connected to the level difference portions, and the excitation electrodes are located at the first portion and the peripheral portion, extending over the level difference portions.