A production method for a surface acoustic wave device comprises the following steps: a step of providing a piezoelectric substrate comprising a transducer arranged on the main front face; a step of depositing a dielectric encapsulation layer on the main front face of the piezoelectric substrate and on the transducer; and a step of assembling the dielectric encapsulation layer with the main front face of a support substrate having a coefficient of thermal expansion less than that of the piezoelectric substrate. In additional embodiments, a surface acoustic wave device comprises a layer of piezoelectric material equipped with a transducer on a main front face, arranged on a substrate support of which the coefficient of thermal expansion is less than that of the piezoelectric material. The transducer is arranged in a dielectric encapsulation layer, between the layer of piezoelectric material and the support substrate.

An elastic wave device includes an interdigital transducer electrode, a dielectric film, and a frequency adjustment film are disposed on a LiNbO.sub.3 substrate. When Euler Angles of the LiNbO.sub.3 substrate are within a range of about 0° ± 5°, within a range of about θ ± 1.5°, within a range of about 0° ± 10°, the interdigital transducer electrode includes a main electrode, a film thickness of the main electrode normalized by a wavelength determined in accordance with an electrode finger pitch of the interdigital transducer electrode is denoted as T, and a density ratio of a material of the main electrode to Pt is denoted as r, the film thickness of the main electrode and θ of the Euler Angles satisfy θ = -0.05°/(T/r - 0.04) + 31.35°.

An elastic wave device includes an interdigital transducer electrode, a dielectric film, and a frequency adjustment film are disposed on a LiNbO.sub.3 substrate. When Euler Angles of the LiNbO.sub.3 substrate are within a range of about 0° ± 5°, within a range of about θ ± 1.5°, within a range of about 0° ± 10°, the interdigital transducer electrode includes a main electrode, a film thickness of the main electrode normalized by a wavelength determined in accordance with an electrode finger pitch of the interdigital transducer electrode is denoted as T, and a density ratio of a material of the main electrode to Pt is denoted as r, the film thickness of the main electrode and θ of the Euler Angles satisfy θ = -0.05°/(T/r - 0.04) + 31.35°.

An elastic wave device includes a piezoelectric layer including a first main surface and a second main surface facing the first main surface, an acoustically reflective layer stacked on the first main surface of the piezoelectric layer, an excitation electrode disposed on the piezoelectric layer, and a support layer. The acoustically reflective layer overlaps at least the excitation electrode in a plan view of the piezoelectric layer from the side of the second main surface. The support layer surrounds the acoustically reflective layer in a plan view of the piezoelectric layer from the side of the second main surface.

An elastic wave device includes a piezoelectric layer including a first main surface and a second main surface facing the first main surface, an acoustically reflective layer stacked on the first main surface of the piezoelectric layer, an excitation electrode disposed on the piezoelectric layer, and a support layer. The acoustically reflective layer overlaps at least the excitation electrode in a plan view of the piezoelectric layer from the side of the second main surface. The support layer surrounds the acoustically reflective layer in a plan view of the piezoelectric layer from the side of the second main surface.

An elastic wave device in which an IDT electrode defines an excitation electrode on a piezoelectric layer, an acoustic reflection layer is laminated on a first main surface of the piezoelectric layer, the acoustic reflection layer includes high acoustic impedance layers with a relatively high acoustic impedance and low acoustic impedance layers with a relatively low acoustic impedance, and the acoustic reflection layer has an unwanted wave reflection suppression structure in which reflection of unwanted waves toward the piezoelectric layer side is significantly reduced or prevented.

An elastic wave device in which an IDT electrode defines an excitation electrode on a piezoelectric layer, an acoustic reflection layer is laminated on a first main surface of the piezoelectric layer, the acoustic reflection layer includes high acoustic impedance layers with a relatively high acoustic impedance and low acoustic impedance layers with a relatively low acoustic impedance, and the acoustic reflection layer has an unwanted wave reflection suppression structure in which reflection of unwanted waves toward the piezoelectric layer side is significantly reduced or prevented.

Embodiments described herein involve methods of forming an interactive card with indicators on a substrate. A plurality of indicators are formed on the substrate by way of a printed electronics process. A plurality of displaceable regions of piezoelectric material are formed on the substrate by way of a printed electronics process. Electrical interconnections are formed on the substrate by way of a printed electronics process, the electrical interconnections connecting an indicator and an associated displaceable region of piezoelectric material such that displacement of the associated displaceable region of piezoelectric material generates a voltage therein that is provided to the indicator in order to actuate the indicator and thereby indicate displacement of the associated displaceable region of piezoelectric material.

Embodiments described herein involve methods of forming an interactive card with indicators on a substrate. A plurality of indicators are formed on the substrate by way of a printed electronics process. A plurality of displaceable regions of piezoelectric material are formed on the substrate by way of a printed electronics process. Electrical interconnections are formed on the substrate by way of a printed electronics process, the electrical interconnections connecting an indicator and an associated displaceable region of piezoelectric material such that displacement of the associated displaceable region of piezoelectric material generates a voltage therein that is provided to the indicator in order to actuate the indicator and thereby indicate displacement of the associated displaceable region of piezoelectric material.

An elastic wave device includes a supporting substrate, a high-acoustic-velocity film stacked on the supporting substrate and in which an acoustic velocity of a bulk wave propagating therein is higher than an acoustic velocity of an elastic wave propagating in a piezoelectric film, a low-acoustic-velocity film stacked on the high-acoustic-velocity film and in which an acoustic velocity of a bulk wave propagating therein is lower than an acoustic velocity of a bulk wave propagating in the piezoelectric film, the piezoelectric film is stacked on the low-acoustic-velocity film, and an IDT electrode stacked on a surface of the piezoelectric film.