Bulk acoustic wave resonator structures include a bulk layer with inclined c-axis hexagonal crystal structure piezoelectric material supported by a substrate. The bulk layer may be prepared without first depositing a seed layer on the substrate. The bulk material layer has a c-axis tilt of about 32 degrees or greater. The bulk material layer may exhibit a ratio of shear coupling to longitudinal coupling of 1.25 or greater during excitation. A method for preparing a crystalline bulk layer having a c-axis tilt includes depositing a bulk material layer directly onto a substrate at an off-normal incidence. The deposition conditions may include a pressure of less than 5 mTorr and a deposition angle of about 35 degrees to about 85 degrees.

The present disclosure relates to an electronic element package and a method of manufacturing the same. The electronic element package includes a substrate, an element disposed on the substrate, and a cap enclosing the element. One of the substrate and the cap includes a groove, the other of the substrate and the cap includes a protrusion engaging with the groove. A first metal layer and a second metal layer form a metallic bond with each other in a space between the groove and the protrusion.

An acoustic wave device includes: a piezoelectric substrate that is made of a single crystal piezoelectric material, and includes a first region including an upper surface, and a second region that is located under the first region and has a density less than a density of the first region; and an IDT located on the upper surface of the piezoelectric substrate.

A thin-film bulk acoustic resonator, a semiconductor apparatus including the acoustic resonator and its manufacturing methods are presented. The thin-film bulk acoustic resonator includes a lower dielectric layer, a first cavity inside the lower dielectric layer, an upper dielectric layer, a second cavity inside the upper dielectric layer, and a piezoelectric film that is located between the first and the second cavities and continuously separates these two cavities. The plan views of the first and the second cavities have an overlapped region, which is a polygon that does not have any parallel sides. The piezoelectric film in this inventive concept is a continuous film without any through-hole in it, therefore it can offer improved acoustic resonance performance.

A filter with bulk acoustic wave devices is disclosed. The filter includes a first bulk acoustic wave resonator and a second bulk acoustic wave resonator. The first bulk acoustic wave resonator includes a first raised frame structure. The first raised frame structure is a multi-layer raised frame structure. The second bulk acoustic wave resonator includes a second raised frame structure. The first raised frame structure has at least one more raised frame layer than the second raised frame structure.

Lateral boundaries of a fluidic passage of a fluidic device incorporating at least one BAW resonator structure are fabricated with photosensitive materials (e.g., photo definable epoxy, solder mask resist, or other photoresist), allowing for high aspect ratio, precisely dimensioned walls. Resistance to delamination and peeling between a wall structure and a base structure is enhanced by providing a wall structure that includes a thin footer portion having a width that exceeds a width of an upper wall portion extending upward from the footer portion, and/or by providing a wall structure arranged over at least one anchoring region of a base structure. Anchoring features may include recesses and/or protrusions.

Devices and methods related to film bulk acoustic resonators. In some embodiments, a film bulk acoustic resonator can be manufactured by a method that includes forming a first electrode having a first lateral shape and providing a piezoelectric layer on the first electrode. The method can further include forming a second electrode having a second lateral shape on the piezoelectric layer such that the piezoelectric layer is between the first and second electrodes. The forming of the first electrode and the forming of the second electrode can include selecting and arranging the first and second lateral shapes to provide a resonator shape defined by an outline of an overlap of the first and second electrodes, such that the resonator shape includes N curved sections joined by N vertices of an N-sided polygon, and such that the resonator shape has no axis of symmetry.

A BAW resonator filter can include a BAW resonator pass-band filter ladder, the BAW resonator pass-band filter ladder can be configured to pass frequency components of an input signal in a pass-band of frequencies received at an input node of the BAW resonator pass-band filter ladder to an output node of the BAW resonator pass-band filter ladder. A first rejection-band series resonator can be coupled in series between an input port of the BAW resonator pass-band filter ladder and the input node, the first rejection-band series resonator can have a first anti-resonant frequency peak in a rejection-band of frequencies that is less than the pass-band of frequencies. A second rejection-band series resonator can be coupled in series between an output port of the BAW resonator filter and the output node, the second rejection-band series resonator can have a second anti-resonant frequency peak in the rejection-band of frequencies.

A filter device includes a first filter including a first input terminal, a first output terminal, a first series arm including first series arm resonators, and first parallel arms connected to the first series arm and each including a first parallel arm resonator, the first filter having a pass band in a predetermined frequency band, a second filter including a second input terminal, a second output terminal, a second series arm including second series arm resonators, and second parallel arms connected to the second series arm and each including a second parallel arm resonator, the second filter having a pass band in the predetermined frequency band, a substrate including the first and second filters, and an inductor connected between a ground terminal and a parallel arm resonator included in at least one parallel arm of the first and second parallel arms.

An acoustic wave device includes a piezoelectric layer including first and second main surfaces facing each other, an IDT electrode on the first main surface and including first and second busbars facing each other and electrode fingers, a first conductor on the second main surface and facing the first busbar with the piezoelectric layer therebetween, and a support on the second main surface and supporting the piezoelectric layer. A cavity that opens towards the piezoelectric layer is provided in the support, and the first conductor is positioned inside the cavity. An electric potential of the first conductor is different from an electric potential to which the first busbar is connected.