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.

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.

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.

A front end module includes a filter portion including filters each including at least one bulk-acoustic wave resonator including a first electrode, a piezoelectric layer, and a second electrode stacked in order, and the filters each have a different allocated passband such that a frequency band of each passband overlaps a portion of a frequency band of an adjacent passband; and a switch portion to be selectively connected to the filters to form a path of a wireless frequency signal.

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.

An FBAR filter device comprising an array of resonators, each resonator comprising a single crystal piezoelectric layer sandwiched between a first and a second metal electrode, wherein the first electrode is supported by a support membrane over an air cavity, the air cavity being embedded in a silicon dioxide layer over a silicon handle, with through-silicon via holes through the silicon handle and into the air cavity, the side walls of said air cavity in the silicon dioxide layer being defined by barriers of a material that is resistant to silicon oxide etchants, and wherein the interface between the support membrane and the first electrode is smooth and flat.

A BAW device includes a substrate, a first reflector, and at least two BAW transducers. The first reflector resides over the substrate and has a plurality of reflector layers. A first BAW transducer resides over a first section of the first reflector, has a first series resonance frequency, and has a first piezoelectric layer of a first thickness between a first top electrode and a first bottom electrode. The second BAW transducer resides over a second section of the first reflector, has a second series resonance frequency that is different than the first series resonance frequency, and has a second piezoelectric layer of a second thickness, which is different than the first thickness, between a second top electrode and a second bottom electrode.

A piezoelectric thin film comprises aluminum nitride containing a monad and at least one type among a tetrad and a pentad. The piezoelectric thin film having a large electromechanical coupling factor and a small stiffness.

A device can include a thin-film bulk acoustic resonator (FBAR), a transceiver, a capacitor network, and a processor. The transceiver can transmit and receive radio frequency (RF) signals using the FBAR. The capacitor network can be conductively coupled to the FBAR. The processor can be in communication with the capacitor network. The processor can obtain a capacitor tuning code. The processor can further establish a capacitance of the capacitor network based on the capacitor tuning code during a RF receiving operation.

A filter includes series units and shunt units. Each series unit includes at least one bulk acoustic wave resonator. Each shunt unit includes at least one bulk acoustic wave resonator and is disposed between one of the series units and a ground. One of the series units or one of the shunt units includes a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, and a third bulk acoustic wave resonator connected in series. The second bulk acoustic wave resonator has a polarity different from a polarity of the first bulk acoustic wave resonator and a polarity of the third bulk acoustic wave resonator.