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A single port multi-resonator acoustic resonator device ( 200, 300, 400, 490) possesses an input impedance that exhibits precisely designed electrical resonances. The device contains at least three parts: a transducer/resonator (201, 301, 401. 491) used both to interface to an external electrical ci

A single port multi-resonator acoustic resonator device ( 200, 300, 400, 490) possesses an input impedance that exhibits precisely designed electrical resonances. The device contains at least three parts: a transducer/resonator (201, 301, 401. 491) used both to interface to an external electrical circuit and to transform electrical energy into mechanical (i.e. acoustic) vibrations (and vice versa), and also function as a resonator; a mechanical (i.e. acoustic) resonator (203, 303, 460, 480) and an acoustic coupler (202, 302, 404, 494) that controls the acoustic interaction between the transducer/resonator and the mechanical resonator.

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What is claimed is: 1. A single-port acoustic resonator device having an input impedance at said port that exhibits at least one electrical resonance within a prescribed frequency band, said prescribed frequency band having a bandwidth that is less than one-half of a central frequency located at th

What is claimed is: 1. A single-port acoustic resonator device having an input impedance at said port that exhibits at least one electrical resonance within a prescribed frequency band, said prescribed frequency band having a bandwidth that is less than one-half of a central frequency located at the center of said prescribed frequency band, said resonator device comprising: a transducer/resonator comprising a layer of piezoelectric material, a first electrode layer comprising an electrically conducting material and a second electrode layer comprising an electrically conducting material, said layer of piezoelectric material being situated between said first electrode layer and said second electrode layer, and said transducer/resonator exhibiting an acoustic resonance within said prescribed frequency band; a mechanical resonator comprising at least one layer of a solid acoustically conductive material, said mechanical resonator exhibiting an acoustic resonance within said prescribed frequency band; an acoustic coupler, said acoustic coupler comprising at least one layer of a solid acoustically conductive material, said acoustic coupler being physically situated between said transducer/resonator and said mechanical resonator for acoustically coupling said transducer/resonator with said mechanical resonator, said transducer/resonator, said acoustic coupler and said mechanical resonator further comprising a stacked integral assembly. 2. The single port acoustic resonator device as defined in claim 1, further comprising: a substrate for supporting said stacked integral assembly of said transducer/resonator, said acoustic coupler and said mechanical resonator; and an acoustic isolator; said acoustic isolator used for substantially inhibiting coupling of acoustic energy to said substrate from any of said transducer/resonator, said mechanical resonator, and said acoustic coupler. 3. The single port acoustic resonator device as defined in claim 2, wherein said substrate and said acoustic isolator are formed in a stacked relationship with said acoustic isolator overlying said substrate and underlying said stacked integral assembly and integrally attached thereto. 4. The single port acoustic resonator device as defined in claim 3, wherein said mechanical resonator is located at a distal end of said stacked integral assembly for permitting access thereto, and wherein said transducer/resonator is located at the proximal end of said stack and is contiguous with an outer surface of said acoustic isolator. 5. The single-port acoustic resonator device as defined in claim 1, wherein said acoustic resonance exhibited by said transducer/resonator comprises a bulk wave acoustic resonance and wherein said acoustic resonance exhibited by said mechanical resonator comprises a bulk wave acoustic resonance. 6. The single port acoustic resonator device as defined in claim 1, wherein said input impedance at said port exhibits at least two electrical resonances within said prescribed frequency band. 7. The single port acoustic resonator device as defined in claim 1, wherein said mechanical resonator further comprises a trimmer layer, said trimmer layer including a layer of solid acoustic energy conductive material having a major surface that is physically accessible. 8. The single port acoustic resonator device as defined in claim 7, wherein said trimmer layer possesses a thickness dimension, said thickness dimension being formed by reduction from a greater thickness dimension by means of etching, ion milling or otherwise to obtain a desired frequency of resonance for said mechanical resonator. 9. The single port acoustic resonator device as defined in claim 7, wherein said trimmer layer possesses a thickness dimension, said thickness dimension being formed by enhancement of a lesser thickness dimension by deposition of additional solid material to obtain a desired frequency of resonance for said mechanical resonator. 10. The single port acoustic resonator device as defined in claim 7, and further comprising a cap layer and a shift layer, wherein said first and second electrode layers are of Al and are 0.2200 μm thick; said cap layer comprises Si3N4 for protecting underlying layers from metal etchant, and is 0.0100 μm thick; said shift layer comprises SiO2 and is 0.0660 μm thick; said piezoelectric layer comprises AlN and is 1.9530 μm thick; said trimmer layer comprises SiO2 is 0.0200 μm thick; said trimmer layer being located on the outside surface of said mechanical resonator and is accessible for ion milling; said mechanical resonator comprises AlN and is 2.3300 μm thick. 11. The single port acoustic resonator device as defined in claim 1 wherein said mechanical resonator further comprises a first layer of solid acoustically conductive material, the first layer of material having a temperature coefficient for its acoustic phase to at least partially offset the temperature coefficient of the acoustic phase velocity of other layers of said mechanical resonator thus inhibiting change in resonant frequency of said mechanical resonator due to a change in temperature. 12. The single port acoustic resonator device as defined in claim 1, wherein said transducer/resonator possesses a thickness dimension that is approximately equal to one-half of an acoustic wavelength (or an integral multiple thereof) at a frequency within said prescribed frequency band; and wherein said mechanical resonator possesses a thickness dimension that is approximately equal to one-half of an acoustic wavelength (or an integral multiple thereof) at a frequency within said prescribed frequency band. 13. The single port acoustic resonator device as defined in claim 1, and wherein said acoustic coupler comprises at least one layer of material having a thickness approximately equal to one-quarter acoustic wavelength or an odd-integral multiple thereof at a frequency within said prescribed frequency band. 14. The single-port acoustic resonator device as defined in claim 1, wherein said acoustic coupler comprises a plurality of layers of solid sound conductive material, said plurality of layers of solid sound conductive material having a combined thickness approximately equal to an integral multiple of one-quarter acoustic wavelengths at a frequency within said prescribed frequency band and wherein at least one of said layers in said plurality of layers comprises a thickness dimension that exceeds one-quarter of an acoustic wavelength at said frequency within said prescribed frequency band. 15. The single port acoustic resonator device as defined in claim 14, wherein said plurality of layers in said acoustic coupler further comprises first, second, third and fourth layers and wherein said second through fourth layers of said acoustic coupler collectively possess an effective impedance between the impedance of W (tungsten) and the impedance of SiO2. 16. The single port acoustic resonator device as defined in claim 1, wherein said transducer/resonator further comprises a first layer of solid acoustically conductive material having an acoustic phase velocity having a positive temperature coefficient and a second layer of acoustically conductive material having an acoustic phase velocity having a negative temperature coefficient that at least partially offsets the change in acoustic phase velocity of the first layer due to change in temperature. 17. The single port acoustic resonator device as defined in claim 1, wherein said acoustic coupler further comprises: alternating layers of SiO2 and AlN arranged in a stack. 18. A frequency filter, comprising: an input port and an output port and a ground, first, second and third acoustic resonator devices connected in series between said input and output ports, fourth and fifth resonator devices; said fourth resonator device connected to the serial connection between said first and second acoustic resonator devices and extending in shunt thereof to ground; said fifth resonator device connected to the serial connection between said second and third acoustic resonator devices and extending in shunt thereof to ground; each of said first through fifth acoustic resonator devices, further comprising: a single-port acoustic resonator device having an input impedance at said port that exhibits at least one electrical resonance within a prescribed frequency band, said prescribed frequency band having a bandwidth that is less than one-half of a central frequency located at the center of said prescribed frequency band, said acoustic resonator device comprising: a transducer/resonator comprising: a layer of piezoelectric material, a first electrode layer comprising an electrically conducting material and a second electrode layer comprising an electrically conducting material, said layer of piezoelectric material being situated between said first electrode layer and said second electrode layer, and said transducer/resonator exhibiting an acoustic resonance within said prescribed frequency band; a mechanical resonator comprising at least one layer of a solid acoustically conductive material, said mechanical resonator exhibiting an acoustic resonance within said prescribed frequency band; an acoustic coupler, said acoustic coupler comprising at least one layer of a solid acoustically conductive material, said acoustic coupler being physically situated between said transducer/resonator and said mechanical resonator for acoustically coupling said transducer/resonator with said mechanical resonator, said transducer coupler, said acoustic coupler and said mechanical resonator further comprising a stacked integral assembly.