Abstract: A substrate processing method for processing a substrate having a first principal surface and a second principal surface at an opposite side to the first principal surface is provided. A polymer film is formed such as to expose a peripheral edge region of the first principal surface and cover an inner side region of the first principal surface positioned further to an inner side than the peripheral edge region and being adjacent to the peripheral edge region (polymer film forming step). After the polymer film forming step, a first cleaning liquid is supplied to the first principal surface such that the polymer film is maintained on the first principal surface (first cleaning liquid supplying step). After the first cleaning liquid supplying step, a removing liquid that dissolves the polymer film more easily than the first cleaning liquid is supplied to the first principal surface (removing liquid supplying step).

Abstract: A piezoelectric actuator (1) includes: a piezoelectric element (3); and a first frictional portion (10) and a second frictional portion (12) that are disposed on one principal surface (2d) of the piezoelectric element (3). The first frictional portion (10) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from one of the end surfaces (2a) is less than ? L, where L represents a length in the longitudinal direction of the piezoelectric element (3). The second frictional portion (12) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from the other of the end surfaces (2b) is less than ? L.

Abstract: In a piezoelectric element, internal stress generated in an inactive portion at the time of sintering when a piezoelectric element is fabricated or stress applied from the outside to the inactive portion is absorbed by a recess of a lower surface of a first through hole conductor and a recess of an upper surface of a second through hole conductor. Accordingly, for example, deformation, rupture, or the like of the through hole conductor is prevented, and conduction failure or disconnection of an electrode layer or a through hole conductor is prevented. Further, in the inactive portion, since a protrusion of the piezoelectric layer enters the recess of the through hole conductor, a holding force of the piezoelectric layer with respect to the through hole conductor increases, and deformation of the through hole conductor is prevented or obstructed.

Abstract: A piezoelectric actuator (1) includes: a piezoelectric element (3); and a first frictional portion (10) and a second frictional portion (12) that are disposed on one principal surface (2d) of the piezoelectric element (3). The first frictional portion (10) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from one of the end surfaces (2a) is less than ? L, where L represents a length in the longitudinal direction of the piezoelectric element (3). The second frictional portion (12) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from the other of the end surfaces (2b) is less than ? L.

Abstract: In a piezoelectric element, internal stress generated in an inactive portion at the time of sintering when a piezoelectric element is fabricated or stress applied from the outside to the inactive portion is absorbed by a recess of a lower surface of a first through hole conductor and a recess of an upper surface of a second through hole conductor. Accordingly, for example, deformation, rupture, or the like of the through hole conductor is prevented, and conduction failure or disconnection of an electrode layer or a through hole conductor is prevented. Further, in the inactive portion, since a protrusion of the piezoelectric layer enters the recess of the through hole conductor, a holding force of the piezoelectric layer with respect to the through hole conductor increases, and deformation of the through hole conductor is prevented or obstructed.