A package for an electrical device

摘要

A piezoelectric device includes a piezoelectric plate provided with at least one electrode at almost a central portion of each face; a first plate made of an ionic material having a recessed portion to cover the at least one electrode at one face to face the piezoelectric plate; and a second plate made of an ionic material having a recessed portion to cover the at least one electrode at one face to face the piezoelectric plate. Each of the at least one electrode is packaged by direct bonding the piezoelectric plate with the first plate and the second plate so as to be sandwiched therebetween. A package includes a body member made of an ionic material provided with a recessed portion or an opening, having a flat face around the recessed portion or the opening; and a covering member made of an ionic material having a flat face to cover the body member. The flat face of the body member and the flat face of the covering member are cleaned and attached to each other so as to be direct bonded with each other using hydrogen bonds generated between the ionic materials, thereby packaging the recessed portion or the opening.