An electret includes a composite oxide having an ABO.sub.3 type perovskite structure containing two different metal elements A and B. The composite oxide is in a polarized state, at least a part of one of the metal elements A and B is substituted with a dopant element having a lower valence than the one of the metal elements A and B, and the composite oxide has a bandgap energy of 4 eV or more.

An element including: a first electrode; an intermediate layer made of a silicone rubber composition containing a silicone rubber; and a second electrode, where the first electrode, the intermediate layer, and the second electrode are disposed in this order, wherein a peak intensity ratio (1095±5 cm.sup.−1/1025±5 cm.sup.−1) of an infrared absorption spectrum of the intermediate layer varies along a vertical direction relative to a surface of the first electrode, and to a surface of the second electrode.

A vibrational energy harvester element includes: a first electrode; a second electrode that moves in a predetermined direction with respect to the first electrode; a third electrode; a fourth electrode that moves in the predetermined direction with respect to the third electrode; and a support portion that supports the second electrode and the fourth electrode so that they are movable along the predetermined direction; and wherein: the first electrode and the third electrode are disposed along the predetermined direction; at least one of facing surfaces of the first electrode and the second electrode, and at least one of facing surfaces of the third electrode and the fourth electrode, are electrically charged; and the support portion supports the second electrode and the fourth electrode in a state in which electrostatic force between the first electrode and the second electrode, and electrostatic force between the third electrode and the fourth electrode are balanced along the predetermined direction.

A vibrational energy harvester element includes: a first electrode; a second electrode that moves in a predetermined direction with respect to the first electrode; a third electrode; a fourth electrode that moves in the predetermined direction with respect to the third electrode; and a support portion that supports the second electrode and the fourth electrode so that they are movable along the predetermined direction; and wherein: the first electrode and the third electrode are disposed along the predetermined direction; at least one of facing surfaces of the first electrode and the second electrode, and at least one of facing surfaces of the third electrode and the fourth electrode, are electrically charged; and the support portion supports the second electrode and the fourth electrode in a state in which electrostatic force between the first electrode and the second electrode, and electrostatic force between the third electrode and the fourth electrode are balanced along the predetermined direction.

A method of manufacturing a MEMS vibration element having a fixed electrode, a movable electrode, and an elastic supporting unit that elastically supports the movable electrode with respect to the fixed electrode includes: etching a base material having a first thickness to form the fixed electrode and the movable electrode; and etching the base material to form the elastic supporting unit having a second thickness, the second thickness being less than the first thickness.

A power generator includes an electret including a first charged surface and a second charged surface having opposite polarities, a first electrode partially formed on the first charged surface, a second electrode formed on the second charged surface, a third electrode disposed to face the first charged surface with a space, and at least one of a power storage unit or an output unit. The first charged surface has a current collecting surface that is exposed outward. The first electrode and the second electrode form a first power generating unit and the third electrode and the second electrode form a second power generating unit. The electret is formed by polarizing an electret material that includes an inorganic dielectric having a bandgap energy of 4 eV or more.

A power generator includes an electret including a first charged surface and a second charged surface having opposite polarities, a first electrode partially formed on the first charged surface, a second electrode formed on the second charged surface, a third electrode disposed to face the first charged surface with a space, and at least one of a power storage unit or an output unit. The first charged surface has a current collecting surface that is exposed outward. The first electrode and the second electrode form a first power generating unit and the third electrode and the second electrode form a second power generating unit. The electret is formed by polarizing an electret material that includes an inorganic dielectric having a bandgap energy of 4 eV or more.

A power generator includes a power generating unit and at least one of a power storage unit or an output unit that is electrically connected to the power generating unit. The power generating unit includes an electret having a first charged surface and a second charged surface that are charged with opposite polarities, a first electrode formed on the first charged surface, and a second electrode formed on the second charged surface. The electret is formed by polarizing an electret material that includes an inorganic dielectric having a bandgap energy of 4 eV or more. At least one of the first electrode or the second electrode are partially disposed on the corresponding charged surface such that at least one of the first charged surface or the second charged surface has a portion as a current collecting surface exposed outward.

A power generator includes a power generating unit and at least one of a power storage unit or an output unit that is electrically connected to the power generating unit. The power generating unit includes an electret having a first charged surface and a second charged surface that are charged with opposite polarities, a first electrode formed on the first charged surface, and a second electrode formed on the second charged surface. The electret is formed by polarizing an electret material that includes an inorganic dielectric having a bandgap energy of 4 eV or more. At least one of the first electrode or the second electrode are partially disposed on the corresponding charged surface such that at least one of the first charged surface or the second charged surface has a portion as a current collecting surface exposed outward.

Provided is an energy conversion film excellent in charge retention performance and suppressed in deterioration of piezoelectricity even if it is exposed to a high temperature environment and an energy conversion element and the like using the film. An energy conversion element comprising: an energy conversion film at least comprises a charged resin film consisting of a resin film at least containing a thermoplastic resin and a metal soap; and an electrode provided on at least one of the two surfaces of the energy conversion film.