A filter package comprising an array of piezoelectric films sandwiched between an array of upper electrodes and lower electrodes: the individual piezoelectric films and the upper electrodes being separated by a passivation material; the lower electrode being coupled to an interposer with a first cavity between the lower electrodes and the interposer; the filter package further comprising a silicon wafer of known thickness attached over the upper electrodes with an array of upper cavities between the silicon wafer and a silicon cover; each upper cavity aligned with a piezoelectric film in the array of piezoelectric films, the upper cavities having side walls comprising the passivation material.

A filter package comprising an array of piezoelectric films sandwiched between lower electrodes and an array of upper electrodes covered by an array of silicon membranes with cavities thereover: the lower electrode being coupled to an interposer with a first cavity between the lower electrodes and the interposer; the array of silicon membranes having a known thickness and attached over the upper electrodes with an array of upper cavities, each upper cavity between a silicon membrane of the array and a common silicon cover; each upper cavity aligned with a piezoelectric film, an upper electrode and silicon membrane, the upper cavities having side walls comprising SiO.sub.2; the individual piezoelectric films, their upper electrodes and silicon membranes thereover being separated from adjacent piezoelectric films, upper electrodes and silicon membranes by a passivation material.

A filter package comprising an array of piezoelectric films comprising an array of mixed single crystals that each comprise doped Aluminum Nitride, typically Al.sub.xGa.sub.(1-x)N or Sc.sub.xAl.sub.(1-x)N, that is sandwiched between an array of lower electrodes and an array of upper electrodes comprising metal layers and silicon membranes with cavities thereover: the array of lower electrodes being coupled to an interposer with a first cavity between the array of lower electrodes and the interposer; the array of silicon membranes having a known thickness and attached over the array of upper electrodes with an array of upper cavities, each upper cavity between a silicon membrane of the array and a common silicon cover; each upper cavity aligned with a piezoelectric film, an upper electrode and silicon membrane, the upper cavities having side walls comprising SiO.sub.2; the individual piezoelectric films, their upper electrodes and silicon membranes thereover being separated from adjacent piezoelectric films, upper electrodes and silicon membranes by a passivation material.

A bulk acoustic wave resonator includes a substrate, a first electrode and a second electrode disposed on the substrate, and a piezoelectric layer disposed between the first electrode and the second electrode. At least one of the first electrode and the second electrode includes an alloy of molybdenum and tantalum.

A bulk acoustic wave resonator device of the present invention comprises: a cavity; a first electrode layer, at least one end of the first electrode layer being located above or inside the cavity; a piezoelectric layer, the cavity and the first electrode layer being located on a first side of the piezoelectric layer; a second electrode layer located on a second side, a region where the first electrode layer, the second electrode layer and the piezoelectric layer overlap being a resonance region; a first passive structure located on the first side and having a first overlapping portion with at least one edge of the first electrode layer; and a second passive structure located on the second side and having a second overlapping portion with at least one edge of the second electrode layer. The first passive structure comprises: a first raised portion located inside the resonance region; and a first extension portion located outside the resonance region, wherein the first raised portion protrudes with respect to the first extension portion. The second passive structure comprises: a second raised portion located inside the resonance region; and a second extension portion located outside the resonance region, wherein the second raised portion protrudes with respect to the second extension portion. The present invention suppresses parasitic edge mode, and improves Z.sub.P and corresponding Q value.

Disclosed are techniques for an integrated circuit (IC) that includes one or more transistors on a substrate and an interconnection structure on the one or more transistors. The interconnection structure includes a semiconductor structure embedded in the interconnection structure. In an aspect, the semiconductor structure includes a cavity structure, a piezoelectric layer over the cavity structure, an upper conductive structure on the piezoelectric layer, and a first contact structure on the upper conductive structure. In an aspect, the cavity structure includes a bottom that is a part of a first etch stop layer over a substrate, a top that is a part of a second etch stop layer over the first etch stop layer, one or more sidewalls connecting the bottom and the top of the cavity structure, and a cavity between the top and the bottom of the cavity structure and surrounded by the one or more sidewalls.

Disclosed is an acoustic wave resonator comprising a substrate material formed of aluminum nitride (AlN) doped with one or more of beryllium (Be), strontium (Sr), and sodium (Na) to enhance performance of the acoustic wave resonator.

A method of forming a film can include heating a CVD reactor chamber containing a substrate to a temperature range between about 750 degrees Centigrade and about 950 degrees Centigrade, providing a first precursor comprising Al to the CVD reactor chamber in the temperature range, providing a second precursor comprising Sc to the CVD reactor chamber in the temperature range, providing a third precursor comprising nitrogen to the CVD reactor chamber in the temperature range, and forming the film comprising ScAlN on the substrate.

The present disclosure provides a packaging method and packaging structure of an FBAR. A second cavity in a resonator cover provided includes a groove in a second substrate and a space surrounded by an elastic bonding material layer. The elastic bonding material layer bonds the resonator cover to a resonant cavity main structure, and elasticity of the elastic bonding material layer is removed after the bonding. Through holes and a conductive interconnection layer on inner surfaces of the through holes are formed on the resonator cover. Since the second cavity includes the groove in the second substrate and the space surrounded by the elastic bonding material layer, which can avoid problems that performance of the elastic bonding material layer is unstable with temperature and humidity changes when the second cavity is entirely surrounded by the elastic bonding material layer, that is, the stability of the resonator is improved.

Methods of fabricating acoustic devices are disclosed. A lateral etch stop is formed in a substrate. A back surface of a piezoelectric plate is attached to a front surface of the substrate. A conductor pattern is formed on the front surface of the piezoelectric plate, the conductor pattern including interleaved fingers of an interdigital transducer (IDT). A cavity is etched in the substrate using an etchant introduced through one or more openings in the piezoelectric plate. A lateral extent of the cavity is defined by the lateral etch stop. After etching the cavity, a portion of the piezoelectric plate forms a diaphragm spanning the cavity with the interleaved fingers of the IDT disposed on the diaphragm.