Abstract: Aspects of this disclosure relate to an acoustic wave device with a piezoelectric layer that includes a wurtzite structure. The wurtzite structure can include aluminum nitride and silicon carbide. Related piezoelectric layers, acoustic wave filters, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: Aspects of this disclosure relate to an acoustic wave device with a temperature compensation layer that includes silicon oxycarbide. The temperature compensation layer can be in physical contact with at least a portion of a piezoelectric layer of the acoustic wave device. The acoustic wave device can be a surface acoustic wave device in certain applications. The acoustic wave device can be a bulk acoustic wave device in some other applications. Related acoustic wave filters, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: Aspects of this disclosure relate to an acoustic wave device with a silicon oxycarbide layer over a trap rich layer. The acoustic wave device can include a piezoelectric layer over the silicon oxycarbide. The acoustic wave device can be a surface acoustic wave device in certain applications. The acoustic wave device can be a bulk acoustic wave device in some other applications. Related acoustic wave filters, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: Aspects of this disclosure relate to an acoustic wave device with a piezoelectric layer that includes a wurtzite structure. The wurtzite structure can include a group 2 element and have a high acoustic velocity. For example, the wurtzite structure can include a carbide and the group 2 element can be carbon of the carbide. The high acoustic velocity can be over 10,000 meters per second. Related piezoelectric layers, acoustic wave filters, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: An integrated bulk acoustic wave resonator-capacitor comprises a membrane including a piezoelectric film, an upper electrode disposed on a top surface of the piezoelectric film, and a lower electrode disposed on a lower surface of the piezoelectric film, a resonator region of the membrane defining a main active domain in which a main acoustic wave is generated during operation, and a capacitor region of the membrane surrounding the resonator region, the capacitor region including a layer of conductive material disposed on the upper electrode, an inner capacitor raised frame defined on an inner peripheral region of the layer of conductive material, and an outer capacitor raised frame defined on an outer peripheral region of the layer of conductive material.

Abstract: An acoustic wave device is provided comprising a substrate and at least one resonator structure of a first type and at least one resonator structure of a second type mounted on the substrate. The resonator structures of the first type are configured to operate as capacitors and have a first thickness, causing the resonator structures to have a first passband frequency range. The resonator structures of the second type have a second thickness that is different from the first thickness, causing the resonator structures to have a second passband frequency range. A method for forming such an acoustic wave device is also provided. A die comprising such an acoustic wave device, a filter comprising such an acoustic wave device, a radio-frequency module comprising such an acoustic wave device, and a wireless mobile device comprising such an acoustic wave device are also provided.

Abstract: A bulk acoustic wave (BAW) resonator is disclosed. The BAW resonator includes: a lower electrode; a piezoelectric layer disposed over the lower electrode; and an upper electrode over the piezoelectric layer. An opening having a first area exists in and extends completely through the upper electrode. The BAW resonator also includes a substrate disposed below the lower electrode; a cavity; and a pillar disposed in the cavity and extending to contact a portion of the lower electrode disposed beneath the opening. The pillar has a second area that is less than the first area. There are no electrical connections that extend across the opening from one side to another.

Abstract: A bulk acoustic wave (BAW) resonator is disclosed. The BAW resonator includes: a lower electrode; a piezoelectric layer disposed over the lower electrode; and an upper electrode over the piezoelectric layer. An opening having a first area exists in and extends completely through the upper electrode. The BAW resonator also includes a substrate disposed below the lower electrode; a cavity; and a pillar disposed in the cavity and extending to contact a portion of the lower electrode disposed beneath the opening. The pillar has a second area that is less than the first area. There are no electrical connections that extend across the opening from one side to another.