US 11,870,422 B2
Bulk acoustic wave resonator filters with integrated capacitors
Saurabh Gupta, Mooresville, NC (US); Zhiqiang Bi, Mooresville, NC (US); Emad Mehdizadeh, Charlotte, NC (US); Dae Ho Kim, Cornelius, NC (US); and Pinal Patel, Charlotte, NC (US)
Assigned to Akoustis, Inc., Huntersville, NC (US)
Filed by Akoustis, Inc., Huntersville, NC (US)
Filed on Dec. 3, 2020, as Appl. No. 17/110,675.
Prior Publication US 2022/0182039 A1, Jun. 9, 2022
Int. Cl. H03H 9/54 (2006.01); H03H 3/02 (2006.01)
CPC H03H 9/542 (2013.01) [H03H 3/02 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A device comprising:
a piezoelectric layer on a substrate and comprising a portion included in an acoustic resonator;
a first conductive layer on the piezoelectric layer and comprising a first electrode of the acoustic resonator on a first side of resonator portion of the piezoelectric layer;
a second conductive layer on the piezoelectric layer and comprising a second electrode of the acoustic resonator on a second side of the resonator portion of the piezoelectric layer;
an insulating layer on the second conductive layer; and
an interconnection metal layer electrically connected to the second conductive layer or the first conductive layer and having a portion extending onto the insulating layer and overlapping a portion of the second conductive layer to provide a first capacitor electrode of a capacitor disposed laterally adjacent the acoustic resonator, coupled to the first electrode and/or the second electrode and having a portion of the second conductive layer as a second capacitor electrode of the capacitor and a portion of the insulating layer between the first and second capacitor electrodes as a dielectric of the capacitor, wherein the acoustic resonator comprises a first acoustic resonator and a second acoustic resonator coupled in series and wherein the capacitor is coupled across the series combination of the first acoustic resonator and the second acoustic resonator.