PROBLEM TO BE SOLVED: To provide a piezoelectric element substrate capable of being reduced in size, and a piezoelectric module, an ultrasonic probe and an ultrasonic device.SOLUTION: An ultrasonic device comprises: an element substrate 41 having a back surface 41A and an operating surface 41B and being disposed with a plurality of opening portions 41C in an array and a plurality of piezoelectric elements 413 provided at an operating surface 41B side of the element substrate 41. Any ones of the plurality of opening portions 41C are through holes 41C2, and the other opening portions 41C are recessed grooves 41C1. The plurality of piezoelectric elements 413 are provided at the operating surface 41B side in groove bottom surfaces of the recessed grooves 41C1. Through electrodes 41D passing through from the operating surface 41B to the back surface 41A of the element substrate 41 and being electrically connected to the piezoelectric elements 413 at the operating surface 41B side are provided on the through holes 41C2.SELECTED DRAWING: Figure 6COPYRIGHT: (C)2017,JPO&INPIT【課題】小型化が可能な圧電素子基板、圧電モジュール、超音波プローブ、及び超音波装置を提供する。【解決手段】超音波デバイスは、背面41A及び作動面41Bを有し、複数の開口部41Cがアレイ状に配置された素子基板41と、素子基板41の作動面41B側に設けられた複数の圧電素子413と、を備え、複数の開口部41Cのうちのいずれかは貫通孔41C2であり、その他の開口部41Cは凹溝41C1であり、圧電素子413は、凹溝41C1の溝底面における作動面41B側に設けられ、貫通孔41C2には、素子基板41の作動面41Bから背面41Aまでを貫通し、作動面41B側において圧電素子413に電気的に接続される貫通電極41Dが設けられている。【選択図】図6
