Acoustic resonator devices and filters are disclosed. An acoustic resonator includes a substrate and a single-crystal piezoelectric plate. A back surface of a supported portion of the piezoelectric plate is attached to a surface of the substrate. A portion of the piezoelectric plate forms a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on a front surface of the piezoelectric plate. The IDT includes first and second busbars, and interleaved fingers extending alternately from the first and second busbars. Overlapping portions of the interleaved fingers are disposed on the diaphragm. At least portions of both the first and second busbars are disposed on the supported portion of the piezoelectric plate. The piezoelectric plate and the IDT are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode within the diaphragm.

A method of forming a piezoelectric film can include providing a wafer in a CVD reaction chamber and forming an aluminum nitride material on the wafer, the aluminum nitride material doped with a first element E1 selected from group IIA or from group IIB and doped with a second element E2 selected from group IVB to provide the aluminum nitride material comprising a crystallinity of less than about 1.5 degree at Full Width Half Maximum (FWHM) to about 10 arcseconds at FWHM measured using X-ray diffraction (XRD).

Acoustic resonator devices and methods are disclosed. An acoustic resonator device includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces. An aluminum oxide etch-stop layer is sandwiched between the surface of the substrate and the back surface of the piezoelectric plate, a portion of the piezoelectric plate and the etch-stop layer forming a diaphragm spanning a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the single-crystal piezoelectric plate with interleaved fingers of the IDT disposed on the diaphragm. The aluminum oxide etch-stop layer is impervious to an etch process used to form the cavity.

A packaging method and a packaging structure of a film bulk acoustic resonator are provided. The packaging method includes: providing a resonant cavity main structure including a first substrate and a film bulk acoustic resonant structure having a first cavity formed therebetween; forming a resonator cover by providing a second substrate and forming an elastic bonding material layer containing a second cavity; bonding the resonant cavity main structure and the resonator cover together through the elastic bonding material layer and removing elasticity of the elastic bonding material layer, where the second cavity is at least partially aligned with the first cavity; forming a through-hole penetrating through the resonator cover and exposing a corresponding electrical connection part of the film bulk acoustic resonant structure; and forming a conductive interconnection layer on a sidewall of the through-hole and on a portion of a surface of the resonator cover.

The present disclosure provides a film bulk acoustic resonator and its fabrication method. The film bulk acoustic resonator includes a first substrate, a first support layer containing a first cavity, a piezoelectric stacked layer, and a first separation structure and/or a second separation structure. The piezoelectric stacked layer includes an effective working region and a parasitic working region; and in the parasitic working region, a first electrode and a second electrode have a corresponding region along a thickness direction. The first separation structure separates the first electrode, and the first electrode of a portion of the parasitic working region is insulated from the first electrode of the effective working region; and the second separation structure separates the second electrode, and the second electrode of a portion of the parasitic working region is insulated from the second electrode of the effective working region.

A front end module (FEM) for a 5.6 GHz Wi-Fi acoustic wave resonator RF filter circuit. The device can include a power amplifier (PA), a 5.6 GHz resonator, and a diversity switch. The device can further include a low noise amplifier (LNA). The PA is electrically coupled to an input node and can be configured to a DC power detector or an RF power detector. The resonator can be configured between the PA and the diversity switch, or between the diversity switch and an antenna. The LNA may be configured to the diversity switch or be electrically isolated from the switch. Another 5.6 GHZ resonator may be configured between the diversity switch and the LNA. In a specific example, this device integrates a 5.6 GHz PA, a 5.6 GHZ bulk acoustic wave (BAW) RF filter, a single pole two throw (SP2T) switch, and a bypassable LNA into a single device.

A method of manufacture for an acoustic resonator device. The method can include forming a topside metal electrode overlying a piezoelectric substrate with a piezoelectric layer and a seed substrate. A topside micro-trench can be formed within the piezoelectric layer and a topside metal can be formed overlying the topside micro-trench. This topside metal can include a topside metal plug formed within the topside micro-trench. A first backside trench can be formed underlying the topside metal electrode, and a second backside trench can be formed underlying the topside micro-trench. A backside metal electrode can be formed within the first backside trench, while a backside metal plug can be formed within the second backside trench and electrically coupled to the topside metal plug and the backside metal electrode. The topside micro-trench, the topside metal plug, the second backside trench, and the backside metal plug form a micro-via.

A package for an electronic component wherein the package comprises a front end, a back end, and an active membrane layer sandwiched between front and back electrodes of conducting material; the active membrane being mechanically supported by the front end and covered by a back end comprising at least one back cavity having organic walls and lid, with filled through vias traversing the organic lid and walls for coupling to the electrodes by an internal routing layer; the vias being coupleable by external solderable bumps to a circuit board for coupling the package in a flip chip configuration.

A piezoelectric device includes a foundation structure and a plurality of metal islands distributed over a first area of a top surface of the foundation structure. A piezoelectric film resides over the foundation structure and is formed from a piezoelectric material. The piezoelectric film has a non-piezoelectric portion over the first area and a piezoelectric portion over a second area of the top surface of the foundation structure. Within the non-piezoelectric portion, the piezoelectric film is polarity patterned to have pillars and a mesh. The pillars of the piezoelectric material have a first polar orientation residing over corresponding ones of the plurality of metal islands. The mesh of the piezoelectric material has a second polar orientation, which is opposite that of the first polar orientation, and surrounds the pillars. In one embodiment, the metal islands are self-assembled islands.

A bulk-acoustic wave resonator includes a substrate; a lower electrode formed on the substrate, and at least a portion of the lower electrode is formed on a cavity; a piezoelectric layer formed on the lower electrode; an upper electrode formed on the piezoelectric layer; a membrane layer formed below the lower electrode and forming the cavity together with the substrate; and a protruding portion formed on the membrane layer and further formed in the cavity in a direction that extends away from the membrane layer.