In at least one embodiment, the electric component comprises a first BAW-resonator (1), a second BAW-resonator (2) electrically connected to the first BAW-resonator and a carrier substrate (3) with a top side (30) on which the BAW-resonators are arranged. The first and the second BAW-resonator each comprise a bottom electrode (11,21) and a top electrode (12,22). The bottom electrodes are in each case located between the carrier substrate and the respective top electrode. A first piezoelectric layer (13) is arranged between the top electrode and the bottom electrode of the first BAW-resonator and laterally protrudes from the first BAW-resonator. The second BAW-resonator is mounted on the first piezoelectric layer in a region laterally next to the first BAW-resonator and comprises a second piezoelectric layer (23) between its top electrode and its bottom electrode. The two piezoelectric layers may have different thickness to realize resonators with different resonance frequencies on the same die.

The present invention relates to a filter circuit (100) comprising a first and a second bulk acoustic wave resonator (2, 3), the first resonator (2) having a first piezoelectric layer (4) structured such that the first resonator (2) has a lower resonant frequency than the second resonator (3), wherein the first piezoelectric layer (4) is structured by recesses (14) passing through the first piezoelectric layer (4), the first resonator (2) and the second resonator (3) as series resonators (102, 105) connected in series with a signal path of the filter circuit (100) or wherein the first resonator (2) and the second resonator (3) as parallel resonators (103, 106) are connected to the signal path of the filter circuit (100) in such a way that in each case one electrode of the resonators is connected to the signal path.

Provided are a resonator, a method of manufacturing the resonator, and a strain sensor and a sensor array including the resonator. The resonator is provided to extend in a lengthwise direction from a support. The resonator includes a single crystal material and is provided to extend in a crystal orientation that satisfies at least one from among a Young's modulus and a Poisson's ratio, from among crystal orientations of the single crystal material.

A BAW component, a lamination for a BAW component, and a method for manufacturing a BAW component are provided. A lamination for a BAW component includes a first layer with a first piezoelectric material and a second layer with a second piezoelectric material that is different than the first piezoelectric material. The first and the second piezoelectric material can be Sc doped AlN and AlN, respectively.

This application provides a monolithic integrated BAW resonator production method, including: preparing an imprint template; forming a mask material layer on a substrate; pressing the mask material layer by using the imprint template in a direction of the substrate, to form a mask groove; performing plasma etching on the substrate by using the mask material layer, as a mask, that is used to form the mask groove, to form, on the substrate, grooves that one-to-one correspond to positions of several mask grooves; and forming, in the several grooves, bottom electrode layers, piezoelectric layers, and top electrode layers that are sequentially stacked, to form resonators of different frequencies.

A method for the batch production of acoustic wave filters comprises: synthesizing N theoretical filters, each filter defined by a set of j theoretical resonator(s) having a triplet C.sub.0ij,eq, .sub.rij,eq and .sub.aij,eq, these parameters grouped into subsets; determining a reference resonator structure for each subset, naturally having a resonant frequency .sub.r,ref, where .sub.aij,eq<.sub.r,ref<.sub.rij,eq; determining, for each theoretical resonator, an elementary building block comprising an intermediate resonator R.sub.ij, a parallel reactance Xp.sub.ij and/or a series reactance Xs.sub.ij, the intermediate resonator R.sub.ij having a triplet C.sub.0ij, .sub.r,ref and .sub.a,ref, the parameters C.sub.0ij, Xpij and/or Xs.sub.ij defined so the elementary building block has a triplet: C.sub.0ij,eq, .sub.rij,eq and .sub.aij,eq; determining the geometrical dimensions of the actual resonators R.sub.ij of the filters so they have a capacitance C.sub.0ij; producing each actual resonator; associating series and/or parallel reactances with actual resonators in order to form the elementary building blocks.

In an array of single crystal acoustic resonators, the effective coupling coefficient of first and second strained single crystal filters are individually tailored in order to achieve desired frequency responses. In a duplexer embodiment, the effective coupling coefficient of a transmit band-pass filter is lower than the effective coupling coefficient of a receive band-pass filter of the same duplexer. The coefficients can be tailored by varying the ratio of the thickness of a piezoelectric layer to the total thickness of electrode layers or by forming a capacitor in parallel with an acoustic resonator within the filter for which the effective coupling coefficient is to be degraded. Further, a strained piezoelectric layer can be formed overlying a nucleation layer characterized by nucleation growth parameters, which can be configured to modulate a strain condition in the strained piezoelectric layer to adjust piezoelectric properties for improved performance in specific applications.

Provided are a resonator, a method of manufacturing the resonator, and a strain sensor and a sensor array including the resonator. The resonator is provided to extend in a lengthwise direction from a support. The resonator includes a single crystal material and is provided to extend in a crystal orientation that satisfies at least one from among a Young's modulus and a Poisson's ratio, from among crystal orientations of the single crystal material.

A BAW device includes a substrate, a first reflector, and at least two BAW transducers. The first reflector resides over the substrate and has a plurality of reflector layers. A first BAW transducer resides over a first section of the first reflector, has a first series resonance frequency, and has a first piezoelectric layer of a first thickness between a first top electrode and a first bottom electrode. The second BAW transducer resides over a second section of the first reflector, has a second series resonance frequency that is different than the first series resonance frequency, and has a second piezoelectric layer of a second thickness, which is different than the first thickness, between a second top electrode and a second bottom electrode.

A bulk acoustic wave (BAW) device comprises a piezoelectric layer disposed between a first electrode layer and a sandwich electrode. The sandwich electrode includes a first layer of a first material having a first acoustic impedance and a second layer of a second material having a second acoustic impedance that is less than the first acoustic impedance of the first layer. The second layer of the sandwich electrode having the lower acoustic impedance is disposed between the first layer and the piezoelectric layer. The sandwich electrode combined with the piezoelectric layer and first electrode can cause the BAW device to resonate at a frequency whose wavelength corresponds to an acoustic cavity length of the BAW device, depending on an acoustic mirror included on one side of the BAW device. In one example, the acoustic cavity length is about 1.5 times of the resonant frequency wavelength.