By successively depositing the layers of a backing material (1), an inorganic piezoelectric element layer (91a), a sound-adjustment layer (94), an organic layer (95), and an electrical conductive layer (96), and dicing at any pitch in the direction of the laminated layers from the electrical conductive layer (96) to the inorganic piezoelectric element layer (91a), pieces of a plurality of inorganic piezoelectric elements (2), a first sound-adjustment layer (3), a lower organic layer (42), and a signal electrode layer (44) are formed by aligning and sequentially overlaying. An upper organic layer (41) and a ground electrode layer (43) are overlain and bonded on the signal electrode layer (44). A plurality of organic piezoelectric elements (5) composed of the signal electrode layer (44), the upper organic layer (41), and the ground electrode layer (43) are formed.