Patent ID: 7067959
Filing Date: 2006-06-27
Classification: H01L,H04R

Abstract:
1. A piezoelectric diaphragm comprising: a multilayer ceramic body including a plurality of piezoelectric ceramic layers, principal-surface electrodes disposed on upper and lower principal surfaces of the multilayer ceramic body, and an internal electrode provided at an interface between adjacent piezoelectric ceramic layers; wherein flexure vibration occurs in the piezoelectric diaphragm when an AC signal is applied between the internal electrode and the upper and lower principal-surface electrode; the upper and lower principal-surface electrodes are electrically connected to each other via a first side surface electrode disposed on one side surface of the multilayer ceramic body; the internal electrode is electrically connected to a second side surface electrode disposed on a side surface that is different from the side surface on which the first side-face electrode is provided; the second side surface electrode is electrically connected to a lead electrode disposed on at least on the upper principal surface of the multilayer ceramic body; the upper and lower principal surfaces of the multilayer ceramic body being substantially entirely covered with a resin layer; a first cutout being 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 being 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; and a third cutout being formed in a side-edge portion, along the second side surface electrode, of the upper resin layer such that the lead electrode is exposed in the third cutout, and the first and second cutouts formed in the upper and lower resin layers, respectively, are at locations that do not oppose each other.