Patent ID: 8564176

Claim:
A piezoelectric MEMS switch comprising: a base substrate; a diaphragm arranged to oppose the base substrate via a gap; a first piezoelectric drive section constituted by layering a first lower electrode, a first piezoelectric body and a first upper electrode on a first surface of the diaphragm, the first surface being across the diaphragm from the gap; a second piezoelectric drive section constituted by layering a second lower electrode, a second piezoelectric body and a second upper electrode on a second surface of the diaphragm, the second surface facing the gap; a fixed electrode provided on a gap side of the base substrate; a movable electrode which is fixed to a second piezoelectric drive section side of the diaphragm and opposes the fixed electrode in such a manner that the movable electrode makes contact with and separates from the fixed electrode according to displacement of the diaphragm; a first unimorph type piezoelectric actuator, which bends the diaphragm in a direction in which the diaphragm comes close to the base substrate by operation d31 mode piezoelectric distortion of the first piezoelectric body, formed by a composition in which the first piezoelectric drive section is disposed on the first surface of the diaphragm; and a second unimorph type piezoelectric actuator, which bends the diaphragm in a direction in which the diaphragm moves away from the base substrate by operation of a d31 mode piezoelectric distortion of the second piezoelectric body, formed by a composition in which the second piezoelectric drive section is disposed on the second surface of the diaphragm, where the first piezoelectric drive section, the diaphragm, and the second piezoelectric drive section constitute a layered structure, where the second upper electrode, the second piezoelectric body, the second lower electrode, the diaphragm, the first lower electrode, the first piezoelectric body, and the first upper electrode are layered in sequence, in a direction from a near side of the base substrate to a far side of the base substrate.