In a method for forming a film bulk acoustic resonator (FBAR), a bulk acoustic wave (BAW) film stack (120) and a support structure (130) are successively formed on a first substrate (100). The support structure (130) includes a primary support wall (131), an isolation wall (132) internal to the primary support wall (131) and a secondary support pillar (133) internal to the isolation wall (132). After a second substrate (200) is bonded and the first substrate (100) is removed, the secondary support pillar (133) and the isolation wall (132) are removed through a release window (120a) in an area delimited by the isolation wall (132). The secondary support pillar (133) contributes to effective support provided during transfer of the films and any other process carried out above the support structure, the isolation wall (132) between the primary support wall (131) and the secondary support pillar (133) can protect the primary support wall (131) against erosion during a process for removing the secondary support pillar (133), providing for high reliability of a cavity (140) subsequently formed within an area delimited by the primary support wall (131).

An RF diplexer circuit device using modified lattice, lattice, and ladder circuit topologies. The diplexer can include a pair of filter circuits, each with a plurality of series resonator devices and shunt resonator devices. In the ladder topology, the series resonator devices are connected in series while shunt resonator devices are coupled in parallel to the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a plurality of series resonator devices, and a pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. A multiplexing device or inductor device can be configured to select between the signals coming through the first and second filter circuits.

An RF diplexer circuit device using modified lattice, lattice, and ladder circuit topologies. The diplexer can include a pair of filter circuits, each with a plurality of series resonator devices and shunt resonator devices. In the ladder topology, the series resonator devices are connected in series while shunt resonator devices are coupled in parallel to the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a plurality of series resonator devices, and a pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. A multiplexing device or inductor device can be configured to select between the signals coming through the first and second filter circuits.

A piezoelectric MEMS resonator is provided. The resonator comprises a single crystal silicon microstructure suspended over a buried cavity created in a silicon substrate and a piezoelectric resonance structure located on the microstructure. The resonator is designed and fabricated based on porous silicon related technologies including selective formation and etching of porous silicon in silicon substrate, porous silicon as scarified material for surface micromachining and porous silicon as substrate for single crystal silicon epitaxial growth. All these porous silicon related technologies are compatible with CMOS technologies and can be conducted in a standard CMOS technologies platform.

An integrated structure of a crystal resonator with a control circuit and an integration method therefor. The crystal resonator is formed by first forming a lower cavity (120) in a device wafer (100) in which a control circuit is formed, forming a piezoelectric vibrator (200) on the device wafer (100) and then enclosing the piezoelectric vibrator (200) within an upper cavity (400) through forming a cap layer (420) using a planar fabrication process, The crystal resonator according to the present invention has a smaller size, which is help for reducing the power consumption thereof, and the crystal resonator is more easily integrated with other semiconductor components, thereby improving the integration of the device.

A bulk-acoustic wave resonator includes: a substrate; and a resonator including a first electrode, a piezoelectric layer, and a second electrode sequentially stacked on the substrate. The piezoelectric layer is formed of aluminum nitride (AlN) containing scandium (Sc), the content of scandium in the piezoelectric layer is 10 wt % to 25 wt %, and the piezoelectric layer has a leakage current density of 1 μA/cm2 or less.

A structure of a semiconductor device is provided, including a circuit substrate. A first metal bulk layer is disposed on the circuit substrate. A buffer layer is disposed on the first metal bulk layer. An absorbing layer is disposed on the buffer layer. A first electrode layer is disposed on the absorbing layer. A plurality of piezoelectric material units are disposed on the first electrode layer. A protection layer is conformally disposed on the piezoelectric material units. A second metal bulk layer is disposed over the piezoelectric material units, and including a first part and a second part. The first part penetrating through the protection layer is disposed on the piezoelectric material units, serving as a second electrode layer. The second part is at a same level of the first part, and at least electrically connecting to the first electrode layer.

A structure and method for integrating a crystal resonator with a control circuit are disclosed. The integration is accomplished by bonding a substrate containing an upper cavity to a device wafer containing both the control circuit and a lower cavity so that a piezoelectric vibrator is sandwiched between the device wafer and the substrate. An increased degree of integration of the crystal resonator and on-chip modulation of its parameters can be achieved by further bonding a semiconductor die to the device wafer. Compared to traditional ones, in addition to being able to integrate with other semiconductor components more easily with a higher degree of integration, the crystal resonator of the present invention is more compact in size and hence less power-consuming.

An acoustic wave device includes a substrate, as well as a first electrode layer, a piezoelectric layer and a second electrode layer which are sequentially arranged on the substrate. The device further includes a protective layer. The protective layer is at least arranged at a first position above the surface, far away from the substrate, of the second electrode layer. The first position is a position, corresponding to a first overlapping region, above the second electrode layer. The first overlapping region, where an active area of the acoustic wave device is located, is at least a part of a region where the first electrode layer, the second electrode layer and the piezoelectric layer are overlapped. A fabrication method for an acoustic wave device is also provided.

A device includes a piezoelectric layer on a substrate and including a portion included in an acoustic resonator, a first conductive layer on the piezoelectric layer and including a first electrode of the acoustic resonator on a first side of resonator portion of the piezoelectric layer, and a second conductive layer on the piezoelectric layer and including a second electrode of the acoustic resonator on a second side of the resonator portion of the piezoelectric layer. An insulating layer is disposed on the second conductive layer and an interconnection metal layer is electrically connected to the second conductive layer or the first conductive layer and has a portion extending onto the insulating layer and overlapping a portion of the second conductive layer to provide a capacitor electrode of a capacitor coupled to the first electrode and/or the second electrode.