Abstract: A method of manufacturing a bonded substrate includes: preparing one or plurality of products to be bonded, each including a brazing material layer and a copper plate laminated on both main surfaces of a ceramic substrate, laminating, one or a plurality of products bonded and a pair of clamping members that clamp them while providing a mold releasing layer between each thereof, heating the one or the plurality of products while pressing the one or the plurality of products in the pair of clamping members to obtain the one or the plurality of bonded substrates in which the ceramic substrate and the copper plate are bonded with a bonding layer, and removing the mold releasing layer from the bonded substrate by dissolving a portion in contact with the mold releasing layer of the copper plate included in the bonded substrate by wet etching.

Abstract: Provided is a method for producing a piezoelectric element in which a piezoelectric body substrate piece is subjected to polarization treatment and a piezoelectric element is produced. The method includes a first step in which the piezoelectric body substrate piece is held on a flat plate-shaped slightly adhesive sheet and a second step in which voltage is applied to the piezoelectric body substrate piece held on the slightly adhesive sheet and the piezoelectric body substrate piece is subjected to polarization treatment.

Abstract: Provided is a method for inspecting a piezoelectric element in which voltage is applied to a piezoelectric element and evaluation of the electrical characteristics of the piezoelectric element is performed. The method includes a first step in which the piezoelectric element is held on a flat plate-shaped slightly adhesive sheet and a second step in which voltage is applied to the piezoelectric element held on the slightly adhesive sheet and evaluation of the electrical characteristics of the piezoelectric element is performed.

Abstract: An opposite-side dielectric ceramic layer is in contact with a first opposite-surface electrode layer and a second opposite-surface electrode layer. A mounting-side dielectric ceramic layer is in contact with a first mounting-surface electrode layer and a second mounting-surface electrode layer. A mounting-side inner electrode layer is separated from the first mounting-surface electrode layer and the second mounting-surface electrode layer by the mounting-side dielectric ceramic layer, disposed on the mounting-side dielectric ceramic layer, extending from a first side-surface electrode layer, and separated from a second side-surface electrode layer. In a cross-sectional view including a lamination direction and a length direction, a position in which the second mounting-surface electrode layer has a maximum thickness is shifted toward a second side surface in the length direction with respect to a position in which the second opposite-surface electrode layer has a maximum thickness.

Abstract: A piezoelectric element includes a piezoelectric body having a main phase configured by lead zirconate titanate and a heterogenous phase configured by a different component to lead zirconate titanate, and a pair of electrodes provided on the piezoelectric body. The piezoelectric body has a surface region within 10 ?m of a surface, and an inner region more than 10 ?m from the surface. A surface area coverage of the heterogenous phase in a cross section of the surface region is at least 0.75% greater than a surface area coverage of the heterogenous phase in a cross section of the inner region.

Abstract: The piezoelectric element comprises a piezoelectric body extending in a lateral direction and a first and second electrodes that are provided on the piezoelectric body. The piezoelectric body has an active portion sandwiched between the first and second electrodes in a thickness direction that is vertical to the lateral direction, and an inactive portion connected to the active portion in the lateral direction. The first electrode has an active electrode portion disposed on the active portion. The active electrode portion includes an interface region that is adjacent to the interface of the active portion and the inactive portion in the lateral direction, and an inner region that is separated from the interface of the active portion and the inactive portion in the lateral direction. The cross sectional surface area per unit length of the interface region in the cross section of the active electrode portion is greater than the cross sectional area per unit length of the inner region.

Abstract: Provided is a method for producing a piezoelectric element in which a piezoelectric body substrate piece is subjected to polarization treatment and a piezoelectric element is produced. The method includes a first step in which the piezoelectric body substrate piece is held on a flat plate-shaped slightly adhesive sheet and a second step in which voltage is applied to the piezoelectric body substrate piece held on the slightly adhesive sheet and the piezoelectric body substrate piece is subjected to polarization treatment.

Abstract: Provided is a method for inspecting a piezoelectric element in which voltage is applied to a piezoelectric element and evaluation of the electrical characteristics of the piezoelectric element is performed. The method includes a first step in which the piezoelectric element is held on a flat plate-shaped slightly adhesive sheet and a second step in which voltage is applied to the piezoelectric element held on the slightly adhesive sheet and evaluation of the electrical characteristics of the piezoelectric element is performed.

Abstract: An opposite-side dielectric ceramic layer is in contact with a first opposite-surface electrode layer and a second opposite-surface electrode layer. A mounting-side dielectric ceramic layer is in contact with a first mounting-surface electrode layer and a second mounting-surface electrode layer. A mounting-side inner electrode layer is separated from the first mounting-surface electrode layer and the second mounting-surface electrode layer by the mounting-side dielectric ceramic layer, disposed on the mounting-side dielectric ceramic layer, extending from a first side-surface electrode layer, and separated from a second side-surface electrode layer. In a cross-sectional view including a lamination direction and a length direction, a position in which the second mounting-surface electrode layer has a maximum thickness is shifted toward a second side surface in the length direction with respect to a position in which the second opposite-surface electrode layer has a maximum thickness.

Abstract: A ceramic element includes: a ceramic body; a first coating layer disposed on a first part of a front surface of the ceramic body; and a second coating layer disposed on a second part of a back surface of the ceramic body. The first coating layer continuously extends from the front surface to a first region of a side surface of the ceramic body, the side surface being a machined surface, and the first region being a front side region of the side surface. The second coating layer continuously extends from the back surface to a second region of the side surface of the ceramic body, the second region being a back side region of the side surface. In the machined surface, one of the first and second coating layers is disposed at least partially on the other of the first and second coating layers.

Abstract: A piezoelectric device is a fired body including a body part 10 and external electrodes 21 and 22. A surface of the side electrode 22 is comprised only of a material for the side electrode 22. On a surface of the surface electrode 21 or a surface of a connection portion where the surface electrode 21 and the side electrode 22 are connected to each other, a protrusion h extending along a direction along which the connection portion extends and sticking out in a thickness direction of the surface electrode 21 is provided. A region, on the surface of the surface electrode 21, farther from the connection portion than the protrusion h is interspersed with a plurality of exposed portions in each of which a surface of a ceramic material having lower solder wettability than a material for the surface electrode 21 is exposed.

Abstract: The piezoelectric element comprises a piezoelectric body extending in a lateral direction and a first and second electrodes that are provided on the piezoelectric body. The piezoelectric body has an active portion sandwiched between the first and second electrodes in a thickness direction that is vertical to the lateral direction, and an inactive portion connected to the active portion in the lateral direction. The first electrode has an active electrode portion disposed on the active portion. The active electrode portion includes an interface region that is adjacent to the interface of the active portion and the inactive portion in the lateral direction, and an inner region that is separated from the interface of the active portion and the inactive portion in the lateral direction. The cross sectional surface area per unit length of the interface region in the cross section of the active electrode portion is greater than the cross sectional area per unit length of the inner region.

Abstract: A piezoelectric element includes a piezoelectric body having a main phase configured by lead zirconate titanate and a heterogenous phase configured by a different component to lead zirconate titanate, and a pair of electrodes provided on the piezoelectric body. The piezoelectric body has a surface region within 10 ?m of a surface, and an inner region more than 10 ?m from the surface. A surface area coverage of the heterogenous phase in a cross section of the surface region is at least 0.75% greater than a surface area coverage of the heterogenous phase in a cross section of the inner region.

Abstract: Provided is a piezoelectric device which has high reliability for the joint between an external electrode and low-melting-point solder. This piezoelectric device is a fired body including a main body part and an external electrode. The external electrode includes a surface electrode that covers upper and lower surfaces of the main body part, and a side-surface electrode that covers a side surface of the main body part and makes a connection to the surface electrode. This piezoelectric device is obtained by co-firing all of constituent members. The surface electrode is configured to include platinum (Pt) or palladium (Pd). The side-surface electrode is also configured to include platinum (Pt) or palladium (Pd). In addition, the side-surface electrode contains gold (Au). The content ratio of gold in the side-surface electrode is preferably 3 to 20 weight %.

Abstract: A method for manufacturing a ceramic device is provided including fixing a ceramic substrate to a reinforcing plate via a sacrifice layer, forming a groove, which penetrates the ceramic substrate and the sacrifice layer and reaches the reinforcing plate, on an upper surface of the ceramic substrate to divide the ceramic substrate into plural ceramic substrates, and removing the sacrifice layer.

Abstract: A piezoelectric device is a fired body including a body part 10 and external electrodes 21 and 22. A surface of the side electrode 22 is comprised only of a material for the side electrode 22. On a surface of the surface electrode 21 or a surface of a connection portion where the surface electrode 21 and the side electrode 22 are connected to each other, a protrusion h extending along a direction along which the connection portion extends and sticking out in a thickness direction of the surface electrode 21 is provided. A region, on the surface of the surface electrode 21, farther from the connection portion than the protrusion h is interspersed with a plurality of exposed portions in each of which a surface of a ceramic material having lower solder wettability than a material for the surface electrode 21 is exposed.

Abstract: There is provided a method for manufacturing a piezoelectric element, the method having a step of polarizing the fired piezoelectric body while fixing at least two positions in a direction perpendicular to the polarization direction. The method is a means for obtaining a piezoelectric element provided with a thin and flat fired piezoelectric body with no warpage.

Abstract: A piezoelectric element is provided with a ceramic substrate including a first surface on which a groove is formed, and a first electrode formed on the first surface of the ceramic substrate and including a crossing part that extends over the groove. At least one void is formed between a bottom of the groove and the crossing part of the first electrode.

Abstract: A ceramic element includes: a ceramic body; a first coating layer disposed on a first part of a front surface of the ceramic body; and a second coating layer disposed on a second part of a back surface of the ceramic body. The first coating layer continuously extends from the front surface to a first region of a side surface of the ceramic body, the side surface being a machined surface, and the first region being a front side region of the side surface. The second coating layer continuously extends from the back surface to a second region of the side surface of the ceramic body, the second region being a back side region of the side surface. In the machined surface, one of the first and second coating layers is disposed at least partially on the other of the first and second coating layers.

Abstract: A provided method for manufacturing a ceramic device 62 includes fixing a ceramic substrate 10 to a reinforcing plate 20 via a sacrifice layer 30, forming a groove, which penetrates the ceramic substrate 10 and the sacrifice layer 30 and reaches the reinforcing plate 20, on an upper surface of the ceramic substrate 10 to divide the ceramic substrate 10 into plural ceramic substrates, and removing the sacrifice layer 30.