A method of forming a piezoelectric thin film can include depositing a material on a first surface of a Si substrate to provide a stress neutral template layer. A piezoelectric thin film including a Group III element and nitrogen can be sputtered onto the stress neutral template layer and a second surface of the Si substrate that is opposite the first surface can be processed to remove that Si substrate and the stress neutral template layer to provide a remaining portion of the piezoelectric thin film. A piezoelectric resonator can be formed on the remaining portion of the piezoelectric thin film.

A bonded body includes a supporting substrate, a silicon oxide layer provided on the supporting substrate, and a piezoelectric material substrate provided on the silicon oxide layer and composed of a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate. The surface resistivity of the piezoelectric material substrate on the side of the silicon oxide layer is 1.710.sup.15 / or higher.

A bonded body includes a supporting substrate, a silicon oxide layer provided on the supporting substrate, and a piezoelectric material substrate provided on the silicon oxide layer and composed of a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate. The surface resistivity of the piezoelectric material substrate on the side of the silicon oxide layer is 1.710.sup.15 / or higher.

Methods of manufacturing an electronic device formed in a cavity may include providing a first substrate having a first side wall including a first metal formed along a periphery on a bottom surface thereof and surrounding an electronic circuit disposed on the bottom surface, providing a second substrate having a second side wall including a second metal and a third metal formed along a periphery on a top surface thereof, aligning the first substrate with the second substrate with the first side wall opposing and contacting the second side wall to internally define a cavity between the bottom surface of the first substrate, the top surface of the second substrate, the first side wall ,and the second side wall, and heating and bonding the first substrate and the second substrate by transient liquid phase bonding.

A bonded body includes a supporting body composed of a ceramic, a bonding layer provided over a surface of the supporting body and composed of one or more material selected from the group consisting of mullite, alumina, tantalum pentoxide, titanium oxide and niobium pentoxide, and a piezoelectric single crystal substrate bonded with the bonding layer. The surface of the supporting body has an arithmetic average roughness Ra of 0.5 nm or larger and 5.0 nm or smaller.

A process for fabricating a substrate for a radiofrequency device includes providing a piezoelectric substrate and a carrier substrate, depositing a dielectric layer on a surface of the piezoelectric substrate, assembling together the piezoelectric substrate and the carrier substrate with a polymerizable adhesive directly between the dielectric layer and the carrier substrate to form an assembled substrate, and polymerizing the polymerizable adhesive layer to form a polymerized layer bonding the piezoelectric substrate to the carrier substrate, the polymerized layer and the dielectric layer together forming an electrically insulating layer between the piezoelectric substrate and the carrier substrate,

A process for fabricating a substrate for a radiofrequency device includes providing a piezoelectric substrate and a carrier substrate, depositing a dielectric layer on a surface of the piezoelectric substrate, assembling together the piezoelectric substrate and the carrier substrate with a polymerizable adhesive directly between the dielectric layer and the carrier substrate to form an assembled substrate, and polymerizing the polymerizable adhesive layer to form a polymerized layer bonding the piezoelectric substrate to the carrier substrate, the polymerized layer and the dielectric layer together forming an electrically insulating layer between the piezoelectric substrate and the carrier substrate,

A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. A first patterned electrode is deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the first electrode and a planarized support layer is deposited over the sacrificial layer, which is then bonded to a substrate wafer. The crystalline substrate is removed and a second patterned electrode is deposited over a second surface of the film. The sacrificial layer is etched to release the air reflection cavity. Also, a cavity can instead be etched into the support layer prior to bonding with the substrate wafer. Alternatively, a reflector structure can be deposited on the first electrode, replacing the cavity.

A method for producing a plurality of piezoelectric multilayer components is disclosed. In an embodiment, a method for producing a plurality of piezoelectric multilayer components includes grinding the piezoelectric multilayer components without an addition of an abrasive by rubbing the piezoelectric multilayer components against one another so that a material abrasion of the piezoelectric multilayer components is carried out.

A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. A first patterned electrode is deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the first electrode and a planarized support layer is deposited over the sacrificial layer, which is then bonded to a substrate wafer. The crystalline substrate is removed and a second patterned electrode is deposited over a second surface of the film. The sacrificial layer is etched to release the air reflection cavity. Also, a cavity can instead be etched into the support layer prior to bonding with the substrate wafer. Alternatively, a reflector structure can be deposited on the first electrode, replacing the cavity.