A piezoelectric diaphragm has principal-surface electrodes formed on upper and lower principal surfaces of a multilayer
ceramic body. An internal
electrode is disposed in an interface between adjacent piezoelectric
ceramic layers. The upper and lower principal surfaces of the multilayer
ceramic body are substantially entirely covered with a resin layer. A first cutout is formed in a side-edge portion, along the first side
surface electrode, of the upper resin layer such that the upper principal-
surface electrode is partially exposed in the first cutout. A second cutout is formed in a side-edge portion, along the first side
surface electrode, of the lower resin layer such that the lower principal-surface
electrode is partially exposed in the second cutout. The locations of the first and second cutouts formed in the upper and lower resin
layers, respectively, are selected such that they do not oppose each other.