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US 12,750,032 B2Granted
Metal-piezoelectric-metal capacitor
AssigneeMurata Manufacturing Co., Ltd.
InventorsAlbert Cardona, Drew Morosin
Life of this patent
Estimating the term…
Abstract
An acoustic resonator is provided that includes a substrate; a piezoelectric layer coupled to the substrate by one or more dielectric layers and having first and second surfaces that oppose each other; an interdigital transducer on at least one of the first and second surfaces of the piezoelectric layer and including interleaved fingers; and a capacitor electrically coupled in parallel to the interdigital transducer and including at least one first electrode on the first surface of the piezoelectric layer and a metal layer on the second surface of the piezoelectric layer, such that the piezoelectric layer is sandwiched between the at least one first electrode and the metal layer.
Claims19
An acoustic resonator comprising:
- a substrate;
- a piezoelectric layer coupled to the substrate by one or more dielectric layers and having first and second surfaces that oppose each other;
- an interdigital transducer (IDT) on at least one of the first and second surfaces of the piezoelectric layer and including interleaved fingers that extend from opposing busbars including a first busbar and a second busbar;
- and
- a capacitor electrically coupled in parallel to the IDT and including:
- (i) at least one first electrode that comprises an anode connected to the first busbar, and (ii) at least one second electrode connected to the second busbar, the at least one first electrode and the at least one second electrode disposed on the first surface of the piezoelectric layer and a metal layer directly disposed on the second surface of the piezoelectric layer, such that the piezoelectric layer is sandwiched between the at least one first electrode and the metal layer,
- wherein the metal layer is a floating metal that at least partially overlaps both the anode and a cathode disposed on the first surface of the piezoelectric layer.
4 more elements
A filter device comprising:
- a plurality of bulk acoustic wave resonators, wherein at least one of the plurality of bulk acoustic wave resonators comprises:
- a substrate;
- a piezoelectric layer coupled to the substrate by one or more dielectric layers and having first and second surfaces that oppose each other;
- an interdigital transducer (IDT) on at least one of the first and second surfaces of the piezoelectric layer and including interleaved fingers that extend from opposing busbars including a first busbar and a second busbar;
- and
- a capacitor electrically coupled in parallel to the IDT and including:
- (i) at least one first electrode that comprises an anode connected to the first busbar, and (ii) at least one second electrode connected to the second busbar, the at least one first electrode and the at least one second electrode disposed on the first surface of the piezoelectric layer and a metal layer directly disposed on the second surface of the piezoelectric layer, such that the piezoelectric layer is sandwiched between the at least one first electrode and the metal layer,
- wherein the metal layer is a floating metal that at least partially overlaps both the anode and a cathode disposed on the first surface of the piezoelectric layer.
5 more elements
A radio frequency module comprising:
- a filter device including a plurality bulk acoustic wave resonators connected in parallel;
- and
- a radio frequency circuit coupled to the filter device, the filter device and the radio frequency circuit being enclosed within a common package, wherein at least one of the plurality of bulk acoustic wave resonators of the filter device includes:
- a substrate;
- a piezoelectric layer coupled to the substrate by one or more dielectric layers and having first and second surfaces that oppose each other;
- an interdigital transducer (IDT) on at least one of the first and second surfaces of the piezoelectric layer and including interleaved fingers that extend from opposing busbars including a first busbar and a second busbar;
- and
- a capacitor electrically coupled in parallel to the IDT and including:
- (i) at least one first electrode that comprises an anode connected to the first busbar, and (ii) at least one second electrode connected to the second busbar, the at least one first electrode and the at least one second electrode disposed on the first surface of the piezoelectric layer and a metal layer directly disposed on the second surface of the piezoelectric layer, such that the piezoelectric layer is sandwiched between the at least one first electrode and the metal layer,
- wherein the metal layer is a floating metal that at least partially overlaps both the anode and a cathode disposed on the first surface of the piezoelectric layer.
7 more elements
Dependencies are inferred from the claim text.