A vibrator includes: a vibration element that includes a pair of first excitation electrodes formed at the first vibration portion, a pair of second excitation electrodes formed at the second vibration portion, and a pair of third excitation electrodes formed at the third vibration portion, in which one second excitation electrode of the pair of second excitation electrodes is formed at a first inclined surface that is inclined with respect to two main surfaces, and one third excitation electrode of the pair of third excitation electrodes is formed at a second inclined surface that is inclined with respect to the two main surfaces and the first inclined surface; and a package that houses the vibration element. The vibration element includes a fixing portion to be fixed to the package. The fixing portion is provided between the first vibration portion and the second and third vibration portions.

A sensor that includes a substrate with a first side having a cavity extending into the first side. A resonator is connected to the substrate and extends over the cavity with the resonator including first and second electrodes overlapping on opposing sides of the piezoelectric crystal. The substrate is connected to the resonator such that one or more physical parameters exerted on the substrate are transferred to the resonator.

The disclosure relates to the technical field of semiconductors, and discloses a method for manufacturing a resonator. The method includes: a substrate is pretreated to change a preset reaction rate of a preset region part of the substrate, so that the preset reaction rate of the preset region part is higher than that of a region outside the preset region part; a preset reaction is performed to the substrate to form a sacrificial material part including an upper half part above an upper surface of the substrate and a lower half part below a lower surface of the substrate; a multilayer structure is formed on the sacrificial material part, and includes a lower electrode layer, a piezoelectric layer and an upper electrode layer from bottom to top; and the sacrificial material part is removed.

A method for manufacturing a Bulk Acoustic Wave (BAW) resonator module is provided. The method includes providing a substrate, defining a platform region on the surface of the substrate, disposing a BAW resonator device on the surface of the substrate within the platform region, and etching an isolation trench circumscribing at least 50% of a circumference of the platform region.

A micromechanical system (MEMS) acoustic wave resonator is formed on a base substrate. A piezoelectric member is mounted on the base substrate. The piezoelectric member has a first electrode covering a first surface of the piezoelectric member and a second electrode covering a second surface of the piezoelectric member opposite the first electrode, the second electrode being bounded by a perimeter edge. A first guard ring is positioned on the second electrode spaced apart from the perimeter edge of the second electrode.

There is provided a laminated substrate having a piezoelectric film, including: a substrate; and a piezoelectric film provided on the substrate interposing a base film, wherein the piezoelectric film has an alkali niobium oxide based perovskite structure represented by a composition formula of (K.sub.1-xNa.sub.x)NbO.sub.3 (0<x<1) and preferentially oriented in (001) plane direction, and a sound speed of the piezoelectric film is 5100 m/s or more.

A resonator element includes: a base portion including a first end surface that faces a first direction and a second end surface that faces a direction opposite to the first direction, a first vibrating arm that is provided integrally with the base portion and is connected to the first end surface; and a second vibrating arm that is provided integrally with the base portion along the first vibrating arm and is connected to the first end surface. When the shortest distance between the first end surface and the second end surface is Wb and an effective width between the shortest distance Wb and the base portion is We, 0.81Wb/We1.70 is satisfied.

A composite substrate that is obtained by bonding a silicon (Si) wafer having an interstitial oxygen concentration of 2 to 10 ppma to a piezoelectric material substrate as a support substrate, and thinning the piezoelectric material substrate after the bonding.

A composite substrate capable of maintaining high resistance after processing at 300 C. and a method of manufacturing the composite substrate are provided. The composite substrate according to the present invention is manufactured by bonding a silicon (Si) wafer having an interstitial oxygen concentration of 2 to 10 ppma to a piezoelectric material substrate as a support substrate, and thinning the piezoelectric material substrate after the bonding. The piezoelectric material substrate is particularly preferably a lithium tantalate wafer (LT) substrate or a lithium niobate (LN) substrate.

A bulk acoustic wave (BAW) device comprises a layer stack including first and second electrodes, a first piezoelectric layer between the electrodes, and a second piezoelectric layer between the first piezoelectric layer and the second electrode. A polarization of a crystal structure of the second piezoelectric layer is opposite to a polarization of a crystal structure of the first piezoelectric layer to achieve higher order resonant frequencies in the BAW device by means other than merely thinning layers in the layer stack. In some examples, the BAW device is a two-terminal device and does not include a metal layer configured to be a third electrode. In some examples, the BAW device includes at least one intermediate layer between the first and second piezoelectric layers, and a total combined thickness of the at least one intermediate layer is less than 4% of a total thickness of the layer stack.