PROBLEM TO BE SOLVED: To provide an ultrasonic device capable of suppressing an excessive increase in the total thickness of a diaphragm and having desired driving characteristics. An ultrasonic device 10 comprises a base material 11 having an opening 111, a diaphragm 12 provided in the base material 11 to close the opening 111, and a piezoelectric element 13 provided in the vibration plate 12. Be prepared. The diaphragm 12 is arranged between the first layer 121 provided on the base material 11 and the first layer 121 and the piezoelectric element 13, and has a second layer 122 that suppresses the diffusion of components contained in the piezoelectric element 13. Be prepared. The bending rigidity of the second layer 122 is larger than the bending rigidity of the first layer 121. [Selection diagram] Fig. 3【課題】振動板の総厚みの過剰な増大を抑制でき、所望の駆動特性を有する超音波デバイスを提供する。【解決手段】超音波デバイス１０は、開孔１１１を有する基材１１と、基材１１に設けられ、開孔１１１を閉塞する振動板１２と、振動板１２に設けられる圧電素子１３と、を備える。振動板１２は、基材１１に設けられる第一層１２１と、第一層１２１及び圧電素子１３との間に配置され、圧電素子１３に含まれる成分の拡散を抑制する第二層１２２とを備える。第二層１２２の曲げ剛性は、第一層１２１の曲げ剛性よりも大きい。【選択図】図３
