A bulk acoustic wave resonator comprises a piezoelectric material layer, a first metal layer disposed on the upper surface of the piezoelectric material layer, a second metal layer disposed on the lower surface of the piezoelectric material layer, and a laterally distributed raised frame including a first raised frame disposed on the upper surface of the first metal layer and having an inner raised frame section with a tapered portion and a non-tapered portion and an outer raised frame section, and a second raised frame disposed beneath the first metal layer and the outer raised frame section, but not beneath the inner raised frame section, the inner raised frame section being laterally disposed from a central active region of the bulk acoustic wave resonator by a first distance, the outer raised frame section being laterally disposed from the central active region by a second distance greater than the first distance.

A BAW resonator with an improved lateral energy confinement is provided. The resonator has a bottom electrode in a bottom electrode layer, a top electrode in a top electrode layer and a piezoelectric layer between the bottom electrode layer and the top electrode layer. The piezoelectric layer comprises piezoelectric materials of different piezoelectric polarities.

A method for manufacturing a piezoelectric device that includes a substrate, a piezoelectric layer directly or indirectly supported by the substrate and arranged above the substrate, a heater, and a heater electrode for driving the heater. Moreover, the method includes forming the piezoelectric layer, the heater, and the heater electrode and subjecting the piezoelectric device to heat treatment with heat generated from the heater by driving the heater by feeding electric power to the heater electrode.

A micro-transfer printable transverse bulk acoustic wave filter comprises a piezoelectric filter element having a top side, a bottom side, a left side, and a right side disposed over a sacrificial portion on a source substrate. A top electrode is in contact with the top side and a bottom electrode is in contact with the bottom side. A left acoustic mirror is in contact with the left side and a right acoustic mirror is in contact with the right side. The thickness of the transverse bulk acoustic wave filter is substantially less than its length or width and its length can be greater than its width. The transverse bulk acoustic wave filter can be disposed on, and electrically connected to, a semiconductor substrate comprising an electronic circuit to control the transverse bulk acoustic wave filter and form a composite heterogeneous device that can be micro-transfer printed.

A BAW resonator with an improved lateral energy confinement is provided. The resonator has a bottom electrode in a bottom electrode layer, a top electrode in a top electrode layer and a piezoelectric layer between the bottom electrode layer and the top electrode layer. The piezoelectric layer comprises piezoelectric materials of different piezoelectric polarities.

An acoustic filter providing negative capacitance for use in multiplexers is provided that may include a first resonator and a second resonator. The second resonator may be a three terminal element that includes two sub-resonator elements having opposite polarities that are mechanically coupled such that as one sub-resonator expands, the other contracts. The second resonator may act as a negative capacitance element relative to the first resonator such that the second resonator provides cancelation at specific frequencies. This structure may further reduce the order of an N-multiplexer ladder network and reduce total insertion loss.

A bulk acoustic wave (BAW) resonator has a bottom electrode, a top electrode over the bottom electrode, and a multilayer piezoelectric structure between the bottom electrode and the top electrode. The multilayer piezoelectric structure has a first piezoelectric layer having a first electromechanical coupling coefficient and a second piezoelectric layer having a second electromechanical coupling coefficient that is different than the first electromechanical coupling coefficient.

A method for manufacturing a piezoelectric device that includes a substrate, a piezoelectric layer directly or indirectly supported by the substrate and arranged above the substrate, a heater, and a heater electrode for driving the heater. Moreover, the method includes forming the piezoelectric layer, the heater, and the heater electrode and subjecting the piezoelectric device to heat treatment with heat generated from the heater by driving the heater by feeding electric power to the heater electrode.

An electronic package includes a first substrate and a second substrate disposed beneath the first substrate. The electronic package also includes a perimeter wall extending between an inner surface of the first substrate and an opposing inner surface of the second substrate to provide separation between the first substrate and the second substrate. A cavity exists between opposing inner surfaces of the first substrate and the second substrate. A first filter comprising a first plurality of bulk acoustic wave (BAW) resonators disposed over the inner surface first substrate. The electronic package also includes a second filter comprising a second plurality of BAW resonators disposed over the second substrate

An acoustic wave device includes a piezoelectric layer, an interdigital transducer, and a slow wave propagation overlay over a portion of the interdigital transducer. By providing electrode fingers of the interdigital transducer such that a portion of the width thereof is dependent on an electrode period, a desirable wave mode may be maintained in the acoustic wave device. Further, by varying a width of the slow wave propagation overlay based on the electrode period, the desirable wave mode may be further maintained.