Abstract: A semiconductor device is provided. The semiconductor device incudes: a first sub-semiconductor structure including a dielectric layer; and a second sub-semiconductor structure, at least including a carrier substrate, and being bonded to the first sub-semiconductor structure. The first sub-semiconductor structure or the second sub-semiconductor structure includes a charge accumulation preventing layer, and the charge accumulation preventing layer is disposed between the carrier substrate and the dielectric layer, and is configured to avoid an undesired conductive channel from being generated due to charge accumulation on a surface of the carrier substrate.

Abstract: A surface acoustic wave (SAW) device includes a substrate; an interdigital transducer (IDT) having lead-out portions and arrays of interdigital electrodes formed on the substrate, wherein the interdigital electrodes includes central portions, end portions, and intermediate portions between the end portions and the lead-out portions, and a thickness of the interdigital electrodes at the end portions is greater than a thickness of the interdigital electrodes at the central portions and the intermediate portions, thereby forming protruding structures at the end portions of the interdigital electrodes; a protective layer formed on the protruding structures at the end portions of the interdigital electrodes; a first temperature compensation layer formed on the protective layer; a second temperature compensation layer formed on the first temperature compensation layer and on the central portions and the intermediate portions of the interdigital electrodes; and a passivation layer formed on the second temperature co

Abstract: A method for fabricating a surface acoustic wave (SAW) device includes forming an interdigital transducer (IDT) having lead-out portions and arrays of interdigital electrodes on a substrate, wherein the interdigital electrodes include central portions, end portions, and intermediate portions between the end portions and the lead-out portions; forming a protective layer on the IDT; forming a first temperature compensation layer on the protective layer; forming openings in the first temperature compensation layer to expose portions of the protective layer on the central portions and the intermediate portions of the interdigital electrodes; and etching the exposed portions of the protective layer, and etching the central portions and the intermediate portions of the interdigital electrodes to a preset thickness, to form protruding structures at the end portions of the interdigital electrodes.

Abstract: A method for fabricating a device having a cavity, includes: obtaining a device wafer including a first substrate and a device structure formed on the first substrate, depositing a first dielectric layer on the device wafer, etching the first dielectric layer to expose at least a part of the device structure and a part of the first substrate, depositing, after the etching, a second dielectric layer on the device wafer and the first dielectric layer, performing a surface treatment on a surface of the second dielectric layer, obtaining a second substrate, and bonding the second substrate with the second dielectric layer on the device wafer, thereby forming the cavity between the second substrate and the device wafer.

Abstract: A bulk acoustic wave resonator and a method of manufacturing the same are provided. The bulk acoustic wave resonator includes: a first carrier substrate; a barrier layer on a main surface of the first carrier substrate and configured to prevent an undesired conductive channel from being generated due to charge accumulation on the main surface; a buffer layer on a side of the barrier layer away from the first carrier substrate; a piezoelectric layer on a side of the buffer layer away from the barrier layer; a first electrode and a second electrode on opposite sides of the piezoelectric layer; a first passivation layer and a second passivation layer, respectively covering sidewalls of the first electrode and the second electrode; a dielectric layer between the first passivation layer and the buffer layer, wherein a first cavity is provided between the first passivation layer and the dielectric layer.

Abstract: A bulk acoustic wave resonator is provided. The bulk acoustic wave resonator incudes a carrier substrate, having a main surface extending along a first direction; a piezoelectric layer, located on a side of the carrier substrate in a second direction perpendicular to the main surface of the carrier substrate; a first electrode and a second electrode; a cavity boundary structure, having a body part extending along the first direction and a protruding part protruding from the body part toward the piezoelectric layer; a resonant cavity, defined by the cavity boundary structure and the piezoelectric layer; and a periphery dielectric layer, located on a side of the protruding part of the cavity boundary structure away from the resonant cavity, a material of the periphery dielectric layer is different from a material of at least a portion of the protruding part adjacent to the periphery dielectric layer.

Abstract: A bulk acoustic wave resonator includes a substrate, a support layer disposed on the substrate, the support layer including a cavity having a polygon shape with more than three sides in a plane crossing a first direction from the substrate to the support layer, a piezoelectric layer disposed on the support layer, a bottom electrode disposed below the piezoelectric layer, partially overlapping the cavity, and extending across a first side of the cavity, and a top electrode disposed above the piezoelectric layer, partially overlapping the cavity, and extending across a second side of the cavity. The bulk acoustic wave resonator further includes at least one release hole formed in the piezoelectric layer and overlapping a portion of the cavity.

Abstract: A method for packaging chips includes: flip-chip bonding a plurality of filter chips to be packaged on a substrate to be packaged; applying a first mold material layer on the filter chips to be packaged; applying a second mold material layer on a side of the first mold material layer away from the filter chip to be packaged, the first mold material layer and the second mold material layer forming a first mold layer; thinning the first mold material layer and the second mold material layer to expose substrates of the filter chips to be packaged, and thinning the substrates of the filter chips to be packaged to a preset thickness; applying a second mold layer on the exposed substrates of the filter chips to be packaged to obtain a mold structure; and cutting the mold structure into a plurality of particle chips.

Abstract: A bulk acoustic wave (BAW) resonator includes a substrate, a piezoelectric layer disposed above the substrate, a first electrode disposed below the piezoelectric layer, a second electrode disposed above the piezoelectric layer, a first dielectric layer, a second dielectric layer, and a third dielectric layer disposed between the substrate and the piezoelectric layer, and a bonding layer disposed between the third dielectric layer and the substrate. The first dielectric layer is disposed below the piezoelectric layer and includes a cavity. The third dielectric layer is disposed below the first dielectric layer and includes a protruding structure protruding towards the piezoelectric layer. The second dielectric layer overlays the third dielectric layer including the protruding structure, the second dielectric layer and the protruding structure of the third dielectric layer constituting a double-wall boundary structure surrounding the cavity.

Abstract: A fabrication method of a bulk acoustic wave (BAW) resonator includes: sequentially forming a buffer layer, a piezoelectric layer, and a first electrode on a temporary substrate; forming a first dielectric layer on the piezoelectric layer and covering the first electrode; forming a trench in the first dielectric layer; forming a second dielectric layer on the first dielectric layer and in the trench; forming a third dielectric layer on the second dielectric layer and filling in the trench; forming a bonding layer on the third dielectric layer; bonding a resonator substrate to the third dielectric layer via the bonding layer; removing the temporary substrate and the buffer layer to expose a surface layer of the piezoelectric layer; removing the surface layer of the piezoelectric layer; forming a second electrode on the piezoelectric layer; and removing a portion of the first dielectric layer surrounded by the trench to form a cavity.

Abstract: A method for packaging chips includes: flip-chip bonding a plurality of filter chips to be packaged on a substrate to be packaged; applying a first mold material layer on the filter chips to be packaged; applying a second mold material layer on a side of the first mold material layer away from the filter chip to be packaged, the first mold material layer and the second mold material layer forming a first mold layer; thinning the first mold material layer and the second mold material layer to expose substrates of the filter chips to be packaged, and thinning the substrates of the filter chips to be packaged to a preset thickness; applying a second mold layer on the exposed substrates of the filter chips to be packaged to obtain a mold structure; and cutting the mold structure into a plurality of particle chips.

Abstract: A film bulk acoustic resonator (FBAR) structure includes a bottom cap wafer, a piezoelectric layer disposed on the bottom cap wafer, a bottom electrode disposed below the piezoelectric layer, and a top electrode disposed above the piezoelectric layer. Portions of the bottom electrode, the piezoelectric layer, and the top electrode that overlap with each other constitute a piezoelectric stack. The FBAR structure further includes a lower cavity disposed below the piezoelectric stack. A projection of the piezoelectric stack is located within the lower cavity.

Abstract: A bulk acoustic wave filter includes: a first bulk acoustic wave resonator including, in an order from bottom to top, a first cavity, a first bottom electrode, a first segment of a piezoelectric layer, and a first top electrode; a second bulk acoustic wave resonator disposed adjacent to the first bulk acoustic wave resonator, and including, in the order from bottom to top, a second cavity, a second bottom electrode, a second segment of the piezoelectric layer, and a second top electrode; a boundary structure surrounding the first cavity and the second cavity, the boundary structure including a boundary portion extending between and separating the first cavity and the second cavity, and the boundary portion being disconnected at a disconnection region; and a first release hole formed in the piezoelectric layer, and overlapping the disconnection region.

Abstract: A method for packaging chips includes: providing a filter wafer and a plurality of substrates to be packaged, each substrate to be packaged being provided with one or more first pads; flip-chip bonding the substrates to be packaged on the filter wafer; molding the substrates to be packaged to form a molded layer on the substrates to be packaged, the substrates to be packaged, the molded layer, and the filter wafer forming a molded structure, each substrate to be packaged, a portion of the molded layer formed on the substrate to be packaged, and the filter wafer together enclosing a cavity; exposing the first pads out of the molded layer; and cutting the molded structure into a plurality of particle chips.

Abstract: A film bulk acoustic resonator (FBAR) structure includes a bottom cap wafer, a piezoelectric layer disposed on the bottom cap wafer, the piezoelectric layer including a single crystalline piezoelectric material, a bottom electrode disposed below the piezoelectric layer; a top electrode disposed above the piezoelectric layer; and a cavity disposed below the bottom electrode.

Abstract: A film bulk acoustic resonator (FBAR) structure includes, a bottom cap wafer, a piezoelectric layer disposed on the bottom cap wafer, the piezoelectric layer including lithium niobate or lithium tantalate, a bottom electrode disposed below the piezoelectric layer, and a top electrode disposed above the piezoelectric layer. Portions of the bottom electrode, the piezoelectric layer, and the top electrode that overlap with each other constitute a piezoelectric stack. The FBAR structure also includes a cavity disposed below the piezoelectric stack. A projection of the piezoelectric stack is located within the cavity.

Abstract: A film bulk acoustic resonator (FBAR) structure includes a top electrode, a piezoelectric layer disposed below the top electrode, a bottom electrode disposed below the piezoelectric layer, a dielectric layer disposed below the bottom electrode, a bonding substrate disposed below the dielectric layer, a bottom cap wafer disposed below the bonding substrate, and a cavity disposed below the bottom electrode and formed by the dielectric layer, the bonding substrate, and the bottom cap wafer.