A piezoelectric/electrostrictive device is provided with a stationary
portion, a thin-plate portion supported by the stationary portion, and
piezoelectric/electrostrictive element formed by alternately laminating a
plurality of electrodes and a plurality of piezoelectric/electrostrictive
layers. The piezoelectric/electrostrictive device is produced by cutting
a thin-plate body that composes the thin-plate portion afterward and a
laminated body comprising the piezoelectric/electrostrictive layers and
thereafter applying prescribed specific processing (for example, heat
treatment) to the cut plane (the lateral end surfaces). By so doing, the
ratio of the actual surface area of the lateral end surface of the
piezoelectric/electrostrictive element to the area of the lateral end
surface of the piezoelectric/electrostrictive element in the orthographic
projection is four or less, and the deposition of moisture on the lateral
end surfaces is suppressed to the extent of not substantially generating
electric leakage or ion migration. As a result, a highly durable
piezoelectric/electrostrictive device can be provided.