PIEZOELECTRIC DEVICE, ULTRASONIC DEVICE, PROBE, AND ELECTRONIC APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a piezoelectric device capable of securely protecting a piezoelectric element from water or moisture.SOLUTION: A substrate 21 of the piezoelectric device includes opening parts 46. The opening parts 46 are covered with a vibration film 24. The vibration film 24 holds a piezoelectric element 25. The vibration film 24 includes: a first layer 48 formed of a material having a water permeability smaller than that of silicon oxide; and a second layer 49, formed by being in close contact with the first layer 48, having a toughness value larger than that of the material forming the first layer 48.SELECTED DRAWING: Figure 3