An acoustic wave device includes a piezoelectric layer including lithium tantalate or lithium niobate, a dielectric film on the piezoelectric layer, the dielectric film including a dielectric material having a higher dielectric constant than that of the lithium tantalate or lithium niobate, and an IDT electrode on the dielectric film.

A method of plugging a hydrocarbon well includes deploying a downhole tool to remove at least a portion of a casing at a section of well to be plugged. Then a plugging material is put downhole onto a blocking device to fill an area to be plugged. An exothermic fluid is added, wherein activation of the exothermic material liquefies the plugging material. Allowing the plugging material and the exothermic fluid to solidify form a cast-in-place plug that fills the section of well to be plugged.

A method of plugging a hydrocarbon well includes deploying a downhole tool to remove at least a portion of a casing at a section of well to be plugged. Then a plugging material is put downhole onto a blocking device to fill an area to be plugged. An exothermic fluid is added, wherein activation of the exothermic material liquefies the plugging material. Allowing the plugging material and the exothermic fluid to solidify form a cast-in-place plug that fills the section of well to be plugged.

Embodiments of this disclosure relate to bulk acoustic wave resonators on a substrate. The bulk acoustic wave resonators include a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, a conductor electrically connecting the first bulk acoustic wave resonator to the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate.

Embodiments of this disclosure relate to acoustic wave filters configured to filter radio frequency signals. An acoustic wave filter includes a first bulk acoustic wave resonator on a substrate, a second bulk acoustic wave resonator on the substrate, a conductor electrically connecting the first bulk acoustic wave resonator in anti-series with the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate. The air gap can reduce parasitic capacitance associated with the conductor. Acoustic wave filters disclosed herein can suppress a second harmonic.

An acoustic resonator filter includes at least one series acoustic resonator, electrically connected between a first port and a second port through which a radio frequency (RF) signal passes, a branch node electrically connected to the at least one series acoustic resonator and having a respective first shunt connection path and a second shunt connection path each extended toward a ground, a first shunt acoustic resonator electrically connected in series with the first shunt connection path, and a second shunt acoustic resonator electrically connected in series with the second shunt connection path, and having a resonance frequency higher than a resonance frequency of the first shunt acoustic resonator. An inductance of the second shunt connection path is higher than an inductance of the first shunt connection path.

A high-pass filter includes: at least one capacitor located in a first pathway between input and output terminals and connected between the input and output terminals; at least one inductor, a first end of the at least one inductor being coupled to the first pathway, a second end of the at least one inductor being coupled to a ground; at least one first acoustic wave resonator located in a second pathway connected in parallel to the first pathway between the input and output terminals, the at least one first acoustic wave resonator being connected in parallel to the at least one capacitor; and at least one second acoustic wave resonator, a first end of the at least one second acoustic wave resonator being coupled to the second pathway, a second end of the at least one second acoustic wave resonator being coupled to a ground.

A transmit filter circuit includes an input terminal, an output terminal, plural series arm resonators, and a parallel arm resonator. The input terminal receives a transmit signal. The output terminal is electrically connected to an antenna. The plural series arm resonators are electrically connected in series with each other on a line between the input and output terminals. The plural series arm resonators include first and second series arm resonators. The first series arm resonator is closest to the output terminal. The second series arm resonator is second closest to the output terminal. A first end of the parallel arm resonator is electrically connected to a node between the first and second series arm resonators. A reference potential is provided to a second end of the parallel arm resonator. The resonant frequency of the first series arm resonator is higher than that of the second series arm resonator.

A method of plugging a hydrocarbon well includes deploying a downhole tool to remove at least a portion of a casing at a section of well to be plugged. Deploying a blocking device downhole to block a bottom of the section of well to be plugged. Deploying a plugging material downhole onto the blocking device to fill an area to be plugged. Deploying an exothermic fluid downhole, wherein activation of the exothermic material liquefies the plugging material. Allowing the plugging material and the exothermic fluid to solidify form a cast-in-place plug that fills the section of well to be plugged.

A front end module includes: a first filter configured to operate as a bandpass filter, and to support communications in a 4.4 GHz to 5.0 GHz band; and a second filter configured to operate as a high-pass filter, and to support communications in a 5.15 GHz to 5.835 GHz band.