Resonator with intrinsic second harmonic cancellation

Abstract

The present disclosure relates to a resonator with intrinsic second harmonic cancellation. The resonator can include a first electrode, a second electrode, and a piezoelectric material between the first electrode and the second electrode, where the piezoelectric material is formed by fabricating the piezoelectric material with a compression axis vector (C-axis vector) oriented along a first direction and applying an electric field across the piezoelectric material to modify the direction of the C-axis vector to be oriented along a second direction. The second direction can be antiparallel to the first direction.

Description

Technical Field

[0001] This disclosure generally relates to resonators, and more specifically, to resonators having a modified amount of compression axial force. Background Technology

[0002] Resonators (e.g., acoustic resonators) are used in many applications, including but not limited to radio frequency (RF) communication applications. For example, resonators are commonly used within RF passband filters in the transmission and / or reception paths. One type of resonator comprises a bulk acoustic resonator formed of a piezoelectric material, which provides acoustic oscillations in response to time-varying electronic signals. For instance, the piezoelectric material may expand or contract along a compression axis (C-axis) in response to an applied voltage, where the C-axis is typically based on the orientation of the piezoelectric material's crystal structure. Furthermore, such resonators can exhibit acoustic resonance modes (e.g., resonant frequencies, resonances, etc.), which can be utilized to provide desired properties when implemented within electronic circuits, such as but not limited to filters.

[0003] There is a growing desire for greater control over the C-axis orientation (e.g., C-axis vector) of one or more piezoelectric materials within a resonator. For example, controlling the C-axis orientation of the piezoelectric material allows for greater flexibility in the design of resonators or circuits such as, but not limited to, filters that incorporate resonators. Summary of the Invention

[0004] According to one or more illustrative embodiments of this disclosure, a resonator is disclosed. In one illustrative embodiment, the resonator includes a first electrode. In another illustrative embodiment, the resonator includes a second electrode. In yet another illustrative embodiment, the resonator includes a piezoelectric material between the first electrode and the second electrode. In yet another illustrative embodiment, the piezoelectric material is formed by manufacturing the piezoelectric material having a C-axis vector oriented along a first direction and applying an electric field across the piezoelectric material to modify the orientation of the C-axis vector to a second direction different from the first direction.

[0005] According to one or more illustrative embodiments of this disclosure, a circuit is disclosed. In one illustrative embodiment, the circuit includes one or more resonators. In another illustrative embodiment, at least one of the one or more resonators includes a first electrode, a second electrode, and a piezoelectric material between the first electrode and the second electrode. In another illustrative embodiment, the piezoelectric material is formed by manufacturing the piezoelectric material having a C-axis vector oriented along a first direction and applying an electric field across the piezoelectric material to modify the direction of the C-axis vector to be oriented along a second direction different from the first direction.

[0006] According to one or more illustrative embodiments of this disclosure, a method is disclosed. In one illustrative embodiment, the method includes fabricating a first electrode. In another illustrative embodiment, the method includes fabricating a piezoelectric material having a compression axis (C-axis) vector oriented along a first direction. In another illustrative embodiment, the method includes applying an electric field across the piezoelectric material to modify the direction of the C-axis vector from the first direction to a second direction, wherein the second direction is different from the first direction. In another illustrative embodiment, the method includes fabricating a second electrode, wherein the piezoelectric material is disposed between the first electrode and the second electrode.

[0007] It should be understood that both the foregoing general description and the following detailed description are exemplary and illustrative only and do not necessarily limit the claimed invention. The accompanying drawings, incorporated in and constituting a part of the specification, illustrate embodiments of the invention and, together with the general description, explain the principles of the invention. Attached Figure Description

[0008] Those skilled in the art can better understand the many advantages of this disclosure by referring to the accompanying drawings.

[0009] Figure 1A This is a flowchart illustrating the steps performed in a method for manufacturing a resonator according to one or more embodiments of the present disclosure.

[0010] Figure 1B This is a flowchart depicting a technique according to one or more embodiments of the present disclosure for applying an electric field across a piezoelectric material to modify the direction of its compression axis (C-axis) vector.

[0011] Figure 1C This is a flowchart depicting additional steps of a method relating to providing an electrical connection to a piezoelectric material according to one or more embodiments of the present disclosure.

[0012] Figure 1D This is a flowchart depicting additional steps of a method relating to manufacturing a resonator having a stacked structure according to one or more embodiments of the present disclosure.

[0013] Figure 2A This is a simplified side view of a portion of a resonator including a first electrode according to one or more embodiments of the present disclosure.

[0014] Figure 2B This is a top view of a sample containing a plurality of first electrodes according to one or more embodiments of the present disclosure.

[0015] Figure 3 This is a simplified side view of a portion of a resonator including a first electrode and a piezoelectric material according to one or more embodiments of the present disclosure.

[0016] Figure 4A This is a simplified side view of a portion of a resonator according to one or more embodiments of the present disclosure, together with a second electrode formed as a conductive plate placed in contact with a piezoelectric material.

[0017] Figure 4B This is a simplified side view of a portion of a resonator according to one or more embodiments of the present disclosure, together with a second electrode formed as a conductive plate separated from the piezoelectric material by a gap.

[0018] Figure 4C This is a simplified side view of a portion of a resonator according to one or more embodiments of the present disclosure, together with a second electrode of a flexible conductive material formed in contact with a portion of the piezoelectric material.

[0019] Figure 5A This is a simplified side view of a portion of a resonator including a second electrode before modification of the C-axis vector, according to one or more embodiments of this disclosure.

[0020] Figure 5B This is a simplified side view of a portion of a resonator including a second electrode after modification of the C-axis vector, according to one or more embodiments of this disclosure.

[0021] Figure 6A It is a depiction of a plurality of first electrodes and electrical paths corresponding to one or more embodiments of the present disclosure. Figure 2A A top view of a portion of the sample.

[0022] Figure 6B A photomask according to one or more embodiments of the present disclosure is depicted for etching at least through a piezoelectric material containing various holes to be etched, wherein at least some of the holes are aligned with electrical paths to be cut.

[0023] Figure 6C Depicting the use of one or more embodiments according to this disclosure Figure 6B A top view of a sample whose electrical path has been cut off by photomask etching.

[0024] Figure 7 This is a simplified side view of a resonator comprising two piezoelectric materials having antiparallel C-axis vector directions and an intermediate electrode, according to one or more embodiments of the present disclosure.

[0025] Figure 8 This is a simplified side view of a resonator comprising two piezoelectric materials having antiparallel C-axis vector directions and without an intermediate electrode, according to one or more embodiments of the present disclosure.

[0026] Figure 9 This is a simplified schematic diagram of a filter comprising a plurality of resonators according to one or more embodiments of the present disclosure, wherein at least one of the resonators has a modified C-axis vector. Detailed Implementation

[0027] The disclosed subject matter will now be described in detail with reference to the accompanying drawings. This disclosure has been shown and described with respect to certain embodiments and their specific features. The embodiments set forth herein are to be considered illustrative rather than restrictive. It will be readily apparent to those skilled in the art that various changes and modifications in form and detail may be made without departing from the spirit and scope of this disclosure.

[0028] As used herein, directional terms (e.g., "top," "bottom," "above," "below," "up," "upward," "downward," "below," and "downward") are intended to provide relative positions for descriptive purposes rather than to specify an absolute reference frame. Those skilled in the art will appreciate various modifications to the described embodiments, and that the general principles defined herein may be applied to other embodiments.

[0029] It should be understood that the architectures depicted are merely exemplary and many other architectures can be implemented to achieve the same functionality. Conceptually, any arrangement of components achieving the same functionality is effectively “associated” to achieve the desired functionality. Therefore, any two components combined herein to achieve a particular functionality can be considered “associated” with each other to achieve the desired functionality, regardless of the architecture or intermediate components. Similarly, any two such associated components can also be considered “connected” or “coupled” to each other to achieve the desired functionality, and any two components that can be suchly associated can also be considered “coupleable” to each other to achieve the desired functionality. Furthermore, unless otherwise indicated, descriptions indicating that one component is “connected” to another component (or, alternatively, “located on another component,” “placed on another component,” etc.) indicate that such components are functionally connected but not necessarily physically in contact. Instead, such components may be physically in contact or alternatively contain intervening elements. Similarly, descriptions of a particular component being “manufactured” on another component indicate the relative position of such components but not necessarily that such components are physically in contact. Such components may be physically in contact or alternatively contain intervening elements.

[0030] Embodiments of this disclosure relate to systems and methods for providing a resonator having at least one piezoelectric material having a compression axis (C-axis) vector modified after manufacturing, wherein the C-axis vector corresponds to the direction of motion of the piezoelectric material in response to an applied electric field. The resonator may include means for exhibiting mechanical oscillations in response to an applied signal, and vice versa. In this way, the resonator can provide a mechanical response to an applied electrical signal or provide an electrical signal in response to mechanical stress. This means can also be considered an acoustic resonator, a sound wave resonator, or a bulk acoustic wave (BAW) resonator.

[0031] The modified C-axis vector can have any orientation relative to the initial C-axis vector. In some embodiments, the modified C-axis vector has an orientation antiparallel to the initial C-axis vector. For example, a modified C-axis vector antiparallel to the initial C-axis vector can have a direction opposite to the initial C-axis vector but oriented along a common axis.

[0032] As used herein, piezoelectric materials can comprise any material or combination of materials that exhibits piezoelectric properties that provide modified structural states (e.g., compressive structural states, extended mechanical states, mechanical stress, etc.) in response to an applied electric field, and vice versa. Specifically, the mechanical deformation of a piezoelectric material in response to an applied electric field can depend on the direction and intensity of the applied electric field and the polarization (e.g., polarization vector) associated with the density of dipoles in the piezoelectric material, wherein the polarization of the material can be characterized as positive or negative and can be based on crystal orientation. It should be noted that the term piezoelectric effect is used herein to broadly refer to both mechanical deformation in response to an applied electric field and the generation of an electric field (e.g., separated charges) in response to mechanical stress.

[0033] Certain combinations of material polarization and electric field can result in positively compressible piezoelectric materials (e.g., type I piezoelectric materials), which are compressed along the C-axis. As another example, certain combinations of material polarization and electric field can result in negatively compressible piezoelectric materials (e.g., type II piezoelectric materials), which are extended along the C-axis.

[0034] As used herein, the term C-axis vector is used to describe whether a piezoelectric material is positively or negatively compressed and whether the compression axis is an extension axis (e.g., the C-axis). Specifically, the C-axis vector is depicted as an arrow, where the orientation of the C-axis in terms of its magnitude indicates the C-axis, and the direction of the arrow indicates whether the piezoelectric material is positively or negatively compressed along this C-axis.

[0035] This paper considers that piezoelectric materials can exhibit different responses to varying intensities of applied electric fields. For example, in response to an electric field intensity within a first range (e.g., an operating range), a piezoelectric material can exhibit temporary mechanical deformation according to the piezoelectric effect. In some cases, within this first range, the mechanical deformation is proportional to the intensity of the applied electric field. Therefore, this first range may be suitable for applications utilizing the piezoelectric effect. As another example, a piezoelectric material can exhibit destructive breakdown when exposed to an electric field with an intensity exceeding the breakdown threshold. For example, applying an electric field across a piezoelectric material with an intensity equal to or exceeding the breakdown threshold can disrupt the piezoelectric properties of the material beyond tolerance, causing a resonator containing the piezoelectric material to operate outside of specified parameters. In another example, applying an electric field across a piezoelectric material with an intensity equal to or exceeding the breakdown voltage can cause dielectric breakdown of the piezoelectric material.

[0036] This paper further considers that, for at least some components of a piezoelectric material, applying an electric field of a specific intensity across the piezoelectric field can induce structural changes affecting the material's polarization and / or C-axis vector. This process can be referred to as polarization. For example, applying an electric field of this intensity range can modify a piezoelectric material from positive compression to negative compression, and vice versa. Furthermore, this structural change can persist after the application of the electric field, making the associated changes in the structural change and the C-axis vector characterizable as permanent or semi-permanent. However, for at least some components of a piezoelectric material, this structural change can be reversed by applying an electric field of a specific intensity in the opposite direction (e.g., polarization in the opposite direction).

[0037] Therefore, the mechanical response of a piezoelectric material to an incident electric field of intensity within a first range (e.g., operating range) can be modified by altering the C-axis vector of the piezoelectric material.

[0038] The composition of the piezoelectric material can be selected to suit the modification of its C-axis vector, such that the electric field in the direction suitable for modifying its C-axis vector is below the corresponding breakdown threshold. In this way, modification of the C-axis vector does not lead to destructive damage to the piezoelectric material.

[0039] In some embodiments, the piezoelectric material may include one or more dopants (e.g., dopant materials) that can reduce the amount of electric field required to modify the C-axis vector. In some embodiments, the resonator includes a piezoelectric material formed of aluminum nitride (AlN) doped with one or more dopants. For example, the resonator may include a piezoelectric material formed of AlN doped with scandium to form aluminum scandium nitride (AlScN or more simply ASN). As another example, the resonator may include a piezoelectric material formed of AlN doped with boron. As yet another example, the resonator may include a piezoelectric material formed of AlN doped with a combination of scandium and boron.

[0040] The C-axis vector can be modified by applying an electric field across the piezoelectric material using any technique known in the art. In some embodiments, the electric field is applied across the piezoelectric material by applying a voltage (e.g., a potential) across the piezoelectric material. However, it should be understood that descriptions or examples referred to herein as applying a voltage across the piezoelectric material are provided for illustrative purposes only and should not be construed as limiting. In this way, descriptions of applying a voltage across the material or applying an electric field across the material are used interchangeably.

[0041] This paper considers using an applied electric field to modify the C-axis vector of a piezoelectric material to enable the fabrication of resonators or other piezoelectric devices, while also ensuring a high electromechanical coupling coefficient (e.g., (or any other suitable metric). In some applications, piezoelectric materials with C-axial magnitude can be directly fabricated in any or selected direction. For example, U.S. Patent No. 9,847,768, published December 19, 2017, generally describes the fabrication of resonators using different seed layers to fabricate multiple piezoelectric layers with antiparallel C-axial magnitudes, the entire contents of which are incorporated herein by reference. However, the electromechanical coupling coefficient can vary for different growth modes, such that directly fabricating piezoelectric layers with different C-axial magnitudes may not provide equivalent performance. In resonators or other devices comprising multiple piezoelectric layers, different electromechanical coupling coefficients of different piezoelectric layers can degrade performance in various ways, such as, but not limited to, reducing harmonic cancellation. Conversely, fabricating piezoelectric layers with C-axial magnitude in a common direction and subsequently modifying the C-axis vector of one or more of the piezoelectric layers can provide a more consistent and, in some cases, better electromechanical coupling coefficient.

[0042] Some embodiments of this disclosure relate to a method of manufacturing a resonator, which includes manufacturing one or more piezoelectric materials and subsequently modifying the C-axis vector of at least one of the piezoelectric materials from an initial state.

[0043] Some embodiments of this disclosure relate to resonators comprising at least one piezoelectric material having a C-axial amount modified from an initial state. This resonator may have any design, including but not limited to thin-film bulk acoustic resonators (FBARs), dual-BARs (DBARs), stacked-BARs (SBARs), or reverse-stacked-BARs (RSBARs).

[0044] Some embodiments of this disclosure relate to a circuit that includes one or more resonators having a modified C-axis vector as disclosed herein. For example, this circuit may be a filter comprising any number of resonators arranged in any manner suitable for a filter design. In some embodiments, all resonators in the circuit are configured to have a modified C-axis vector as disclosed herein. In some embodiments, the circuit includes resonators with different designs, wherein at least one of the resonators has a modified C-axis vector as disclosed herein.

[0045] For reference Figures 1A to 8 The present disclosure describes in more detail a system and method for providing a resonator with at least one piezoelectric material having a modified C-axis vector (e.g., relative to an initial direction or orientation) according to one or more embodiments.

[0046] Figure 1A This is a flowchart illustrating the steps performed in a method 100 for manufacturing a resonator according to one or more embodiments of the present disclosure. It should be understood that method 100 is not limited to... Figure 1AThe specific steps described herein. In some embodiments, method 100 may include additional steps that may be performed before, after, and / or between any of the described steps. In some embodiments, no additional steps are performed. Figure 1A All the steps described in the document.

[0047] As used herein, descriptions and / or illustrations of the manufacture of one component or material on another component or material are intended to indicate the relative orientation of the various components. However, such descriptions and / or illustrations are merely illustrative and should not be construed as limiting. Unless otherwise indicated, descriptions and illustrations of the manufacture of one component on another component may be applied to embodiments in which the two components are in direct physical contact and embodiments in which an intervening component is located between the two components.

[0048] Figures 2A to 8 Various non-limiting descriptions are depicted of the resonator 200 on the sample 202 manufactured using the steps of method 100. It should be understood that this document... Figures 2A to 8 The embodiments and enabling technologies described in the context should be interpreted as extensions of method 100. However, method 100 is not limited to... Figures 2A to 8 The description in the text.

[0049] In some embodiments, method 100 includes step 102 of manufacturing a first electrode 204 (e.g., a conductor through which electricity enters or leaves). Figure 2A This is a simplified side view of a portion of a resonator 200 including a first electrode 204 according to one or more embodiments of this disclosure. The first electrode 204 may be formed of any suitable conductive material, including, but not limited to, molybdenum (Mo) or tungsten (W).

[0050] The first electrode 204 can be fabricated on any suitable material. In some embodiments, such as Figure 2A As illustrated, the first electrode 204 is fabricated on the substrate 206. In some embodiments, although not shown in the figures, the first electrode 204 is at least partially fabricated on a cavity (e.g., a cavity in the substrate 206). In some embodiments, the first electrode 204 is fabricated as an intermediate electrode in a stacked structure. For example, the first electrode 204 may be fabricated on a material layer, such as, but not limited to, a piezoelectric material layer.

[0051] Figure 2B This is a top view of a sample 202 comprising a plurality of first electrodes 204 (e.g., for forming a plurality of resonators 200) according to one or more embodiments of the present disclosure. Specifically, Figure 2BThe portion illustrating sample 202 includes a plurality of bare dies 208 separated by channel 210, each of which includes a plurality of first electrodes 204 surrounded by sealing ring 212. It should be understood that the specific description of the bare dies 208 and the constituent components is provided for illustrative purposes only and should not be construed as limiting. Rather, sample 202 may contain any number of first electrodes 204 of any size or distribution. Furthermore, the bare dies 208 do not necessarily need to include sealing ring 212.

[0052] For reference Figure 1A and Figure 3 In some embodiments, method 100 includes a step 104 of manufacturing a piezoelectric material 302 having a C-axis vector 304 oriented along an initial direction. Step 104 of manufacturing the piezoelectric material 302 can be performed using any technique known in the art, including but not limited to sputtering techniques. Figure 3 This is a simplified side view of a portion of a resonator 200 including a first electrode 204 and a piezoelectric material 302 according to one or more embodiments of the present disclosure.

[0053] exist Figure 3 In this diagram, the C-axis vector 304 is represented as an arrow pointing in the +Z direction (e.g., away from the substrate 206), such that the piezoelectric material 302 is positively compressed along the Z-axis. This initial direction of the C-axis vector 304 may be determined by or at least influenced by the structure of the piezoelectric material 302 (e.g., the orientation of its crystal structure). However, it should be understood that the C-axis vector 304 may have any initial direction and is not limited to this. Figure 3 The direction described in the text.

[0054] This paper considers that the piezoelectric material 302 can generally be formed from any composition suitable for providing a piezoelectric effect and that the orientation of the C-axis vector 304 can be modified by applying an electric field after fabrication. For example, the piezoelectric material 302 may contain any material with piezoelectric properties suitable for use in the resonator 200, such as, but not limited to, AlN or zinc oxide (ZnO) and variations thereof.

[0055] In some embodiments, piezoelectric material 302 comprises a substrate material and one or more dopant materials (e.g., dopants). For example, piezoelectric material 302 may comprise a substrate material doped with one or more rare earth metals, such as, but not limited to, scandium, yttrium, lanthanum, or elements having atomic numbers in the range of 58 to 71. As an example, piezoelectric material 302 may comprise a substrate material of AlN doped with scandium to form an ASN. In some embodiments, piezoelectric material 302 is formed as AlN doped with a concentration of about 35% or less scandium. In some embodiments, piezoelectric material 302 is formed as AlN doped with a concentration of about 22% or less scandium. As another example, piezoelectric material 302 may comprise a substrate material doped with boron. In some embodiments, piezoelectric material 302 is formed as AlN doped with a concentration of about 7% boron. As another example, piezoelectric material 302 may comprise a substrate material doped with a combination of two or more different dopants. As an example, piezoelectric material 302 may comprise AlN doped with a combination of scandium and boron. However, it should be understood that the examples in this document are illustrative only and do not limit this disclosure.

[0056] This paper further considers that the composition of the piezoelectric material 302 can be customized to provide a balance of various properties, such as, but not limited to, modifying the electric field strength required for the C-axis vector 304, electromechanical coupling properties (e.g., by...). Or any other suitable metric) or thermal properties. For illustration, a specific composition of AlN having one or more doped materials (e.g., rare earth metals, boron, or any other suitable material) can be selected to reduce the electric field strength required to modify the C-axis vector 304 (or more generally, to polarize the material) to a value or range below the breakdown threshold of AlN (or more generally, the substrate material). In this way, the C-axis vector 304 can be modified without damaging the piezoelectric material 302. Furthermore, the specific composition and / or concentration of the dopants can affect additional properties, such as, but not limited to, electromechanical coupling properties. For example, in some cases, boron-doped AlN can provide lower [electric field strength] than scandium-doped AlN. Measurement. In this way, The specific value of the metric can be tuned by selecting the concentrations of boron and scandium dopants, while retaining the ability to modify the C-axis vector 304 by applying an electric field as disclosed herein.

[0057] like Figure 3As illustrated, the piezoelectric material 302 can be directly fabricated on the first electrode 204. In some embodiments, although not shown in the figures, the piezoelectric material 302 can be fabricated using one or more intervening materials between the first electrode 204 and the piezoelectric material 202. For example, the resonator 200 may include one or more seed layers to facilitate the fabrication of the piezoelectric material 302. For example, the resonator 200 may include a polarization determining seed layer (PDSL) to provide a C-axis vector 304 with a selected initial orientation. The use of a PDSL to control the initial orientation of the C-axis vector 304 of a piezoelectric material is substantially described in U.S. Patent No. 9,847,768, which is referenced above and the entire contents thereof are incorporated herein by reference.

[0058] In some embodiments, method 100 includes step 106 of applying an electric field across piezoelectric material 302 to modify the orientation of C-axis vector 304. C-axis vector 304 can be modified to have any orientation different from the initial orientation. Thus, the orientation of the C-axis of piezoelectric material 302 and / or whether piezoelectric material 302 is positively or negatively compressed can be modified by applying an electric field. In some embodiments, C-axis vector 304 is modified to have an antiparallel orientation to the initial orientation. In this way, modification of C-axis vector 304 can cause piezoelectric material 302 to flip from positive compression to negative compression (and vice versa) along the initial C-axis (here, the Z-axis). As will be described in more detail below, this document considers that modifying C-axis vector 304 to be antiparallel to the initial orientation can facilitate the fabrication of stacked resonators with antiparallel C-axis vector 304 to provide cancellation of higher-order resonant modes (e.g., cancellation of second-order resonant modes) and high electromechanical coupling metrics.

[0059] Step 106 can be performed using any technique suitable for modifying the orientation of the C-axis vector 304, such as, but not limited to, applying a voltage between two electrodes on opposite sides of the piezoelectric material 302. For example, a voltage can be applied between the first electrode 204 and an additional electrode located on opposite sides of the piezoelectric material 302.

[0060] For reference Figures 4A to 5B In some embodiments, the second electrode 402 is placed on or near the piezoelectric material 302 on the side opposite to the first electrode 204 and is subsequently used to apply an electric field across the piezoelectric material 302 to modify the orientation of its C-axis vector 304. For example, step 106 of method 100 may include applying a voltage between the second electrode 402 and the first electrode 204 to generate an electric field across the piezoelectric material 302 suitable for modifying its C-axis vector 304.

[0061] Figures 4A to 4C Various non-limiting embodiments are described, illustrating how a voltage is applied between the second electrode 402 and the first electrode 204 to modify the C-axis vector 304 of the piezoelectric material 302. For example, Figures 4A to 4C A source 404 (e.g., a voltage source, etc.) connected to the second electrode 402 and the first electrode 204 is depicted, and further depicted along the -Z direction (e.g., antiparallel to). Figure 3 The +Z direction oriented C-axis vector 304, as described, indicates that the piezoelectric material 302 is now negatively compressed along the Z-axis. The source 404 can be connected to the second electrode 402 and the first electrode 204 in any configuration to provide any voltage suitable for modifying any polarity of the C-axis vector 304 of the piezoelectric material 302. Figures 4A to 4C As described, the first electrode 204 can be connected to ground, and the source 404 can apply a desired voltage to the second electrode 402 relative to ground. As another example, the source 404 can apply a voltage between the second electrode 402 and the first electrode 204 without referencing an external ground.

[0062] The values ​​of the electric field and / or voltage required to modify the C-axis vector 304 can depend on various factors, such as, but not limited to, the composition or thickness of the piezoelectric material 302, and any intervening layers. For example, a voltage of approximately 70V may be suitable for modifying the C-axis vector 304 having an ASN of approximately 35% scandium. As another example, a voltage of approximately 100V may be suitable for modifying the C-axis vector 304 having an ASN of approximately 22% scandium. However, as described earlier herein, it should be understood that these values ​​are illustrative only and should not be construed as limiting. Any value of electric field and / or voltage suitable for modifying the C-axis vector 304 can be applied. Furthermore, for a given composition of the piezoelectric material 302, a range of electric fields and / or voltages may be suitable for modifying the C-axis vector 304.

[0063] In some embodiments, the second electrode 402 is formed of a component separate from (e.g., independent of) the resonator 200. In this way, the second electrode 402 can be temporarily placed on or near the piezoelectric material 302 to help modify its C-axis vector 304, without being fabricated as a layer itself. Furthermore, the second electrode 402 can be any conductive material suitable for use as an electrode across the piezoelectric material 302, such as, but not limited to, metals.

[0064] For example, the second electrode 402 may include a conductive plate that can be placed on or near the piezoelectric material 302. Figure 4A This is a simplified side view of a portion of a resonator 200 according to one or more embodiments of the present disclosure, together with a second electrode 402 formed as a conductive plate placed in contact with a piezoelectric material 302. Figure 4BThis is a simplified side view of a portion of the resonator 200 according to one or more embodiments of the present disclosure, together with a second electrode 402 formed as a conductive plate separated from the piezoelectric material 302 by a gap 406. It is contemplated herein that the piezoelectric material 302 may generally have a sufficiently high dielectric constant (e.g., relative dielectric constant) such that applying a voltage between the second electrode 402 and the first electrode 204 will result in an electric field across the piezoelectric material 302 that is relatively stronger than the electric field across the gap 406.

[0065] As another example, the second electrode 402 may comprise a flexible conductive material, such as, but not limited to, a plunger that can be positioned to at least partially contact the piezoelectric material 302. Figure 4C This is a simplified side view of a portion of a resonator 200 according to one or more embodiments of the present disclosure, together with a second electrode 402 of a flexible conductive material formed in contact with a portion of a piezoelectric material 302. (As shown in...) Figure 4B In the cases described herein, the relatively high dielectric constant of the piezoelectric material 302 relative to the ambient atmosphere can result in a relatively high electric field across the piezoelectric material 302. Furthermore, as previously described, the range of electric field values ​​may be adapted to modify the C-axis vector 304 of the piezoelectric material 302 such that the variation in the electric field across the piezoelectric material 302 caused by partial or non-uniform contact between the second electrode 402 and the piezoelectric material 302 is negligible or at least within acceptable tolerances.

[0066] In some embodiments, the second electrode 402 is formed as a material directly fabricated on one or more additional components of the resonator 200, such as, but not limited to, a conductive layer of piezoelectric material 302.

[0067] Figure 1B This is a flowchart depicting a technique according to one or more embodiments of the present disclosure for applying an electric field across a piezoelectric material 302 to modify the orientation of its C-axis vector 304. Figure 5A This is a simplified side view of a portion of a resonator 200 including a second electrode 402 before modification of the C-axis vector 304, according to one or more embodiments of this disclosure. Figure 5B This is a simplified side view of a portion of the resonator 200 including the second electrode 402 after modification of the C-axis vector 304, according to one or more embodiments of this disclosure.

[0068] In some embodiments, method 100 includes step 108 of fabricating a second electrode 402. For example, the second electrode 402 may be fabricated on the opposite side of the piezoelectric material 302 as a first electrode 204. The second electrode 402 may be fabricated to be in direct physical contact with the piezoelectric material 302, or an intervening layer may be present between the piezoelectric material 302 and the second electrode 402. The second electrode 402 may be formed of any suitable conductive material, including but not limited to molybdenum (Mo) or tungsten (W).

[0069] In some embodiments, method 100 includes step 110 of applying an electric field between the second electrode 402 and the first electrode 204 to modify the orientation of the C-axis vector 304. For example, step 110 can be performed by applying a voltage between the second electrode 402 and the first electrode 204, such as... Figure 5B As explained in the text.

[0070] In some embodiments, method 100 includes step 112 of removing the second electrode 402. The second electrode 402 can be removed using any technique known in the art, including but not limited to etching. As described in more detail below, in some embodiments, the second electrode 402 may be removed in step 112 after modifying the C-axis vector 304 of the piezoelectric material 302 to accommodate a resonator design without an intervening electrode. Alternatively, in some embodiments, step 112 is omitted and the second electrode 402 is retained, in whole or in part, as a component of the resonator 200 to accommodate additional resonator designs.

[0071] Again, for general reference Figures 1A to 1C The present disclosure describes in more detail various non-limiting considerations and methods for applying a voltage between the second electrode 402 and the first electrode 204 to modify the C-axis vector 304 of the piezoelectric material 302, according to one or more embodiments. It should be noted that applying a voltage between the second electrode 402 and the first electrode 204 requires establishing an electrical connection between each of these electrodes and the source 404.

[0072] In some embodiments, method 100 includes connecting leads from source 404 to first electrode 204 and / or second electrode 402 to provide a voltage between first electrode 204 and second electrode 402 for modifying the C-axis vector 304 of piezoelectric material 302. For example, in some designs, first electrode 204 and / or second electrode 402 may be readily accessible, allowing leads to direct contact with first electrode 204 and / or second electrode 402. As an illustration, second electrode 402 may be configured as a separate electrode (e.g., as...). Figures 4A to 4C (as described in the text) and can be directly connected to source 404. As another illustration, the first electrode 204 and / or the second electrode 402 (e.g., as described in the text) Figures 5A to 5B The conductive layer of the material described herein can be connected to the source 404 by one or more leads placed in direct contact with the first electrode 204 and / or the second electrode 402.

[0073] In some embodiments, method 100 includes connecting the first electrode 204 and / or the second electrode 402 to the source 404 using one or more electrical paths to electrical contacts. As used herein, the electrical path may include any number of conductive components suitable for providing an electrical connection between two objects and may include, but is not limited to, wires, electrical traces (e.g., conductive paths on a circuit board), pads, conductive sealing rings 212 (e.g., as shown in the image), etc. Figure 2B (As illustrated in the diagram) or an electrical network (e.g., a series of electrical traces in a channel 210 between bare dies 208 providing electrical connections between components such as, but not limited to, sealing ring 212). Furthermore, in applications where multiple resonators 200 with a modified C-axis vector 304 orientation are to be fabricated, it may be desirable to provide electrical paths between common electrodes (e.g., between multiple first electrodes 204 and / or between multiple second electrodes 402) such that the C-axis vector 304 orientation of the various piezoelectric materials 302 can be modified simultaneously. Electrical contacts may comprise any conductive component that is physically accessible to the source 404 (or leads attached to the source 404), such as, but not limited to, a conductive pad or plate.

[0074] In this manner, method 100 may include creating one or more electrical paths to an accessible source 404 to the first electrode 204 and / or the second electrode 402 before modifying the direction of the C-axis vector 304 of the piezoelectric material 302.

[0075] After modifying the C-axis vector 304 of the piezoelectric material 302, the electrical path and / or electrical pad can optionally be cut off or otherwise disrupted. In this way, the piezoelectric material 302, which forms part of the complete resonator 200, can be connected to additional components in the circuit using electrical connections different from those used to modify the C-axis vector 304 of the piezoelectric material 302.

[0076] For reference Figure 1C and Figures 6A to 6C The present disclosure describes the fabrication of an electrical path providing an electrical connection to a piezoelectric material 302 according to one or more embodiments.

[0077] Figure 1C This is a flowchart depicting additional steps of a method 100 relating to providing an electrical connection to a first electrode 204 according to one or more embodiments of the present disclosure. Figures 6A to 6C This describes sample 202 at various manufacturing steps associated with method 100.

[0078] In some embodiments, method 100 includes step 114 of creating one or more electrical paths 602 from the first electrode 204 to the electrical contact.

[0079] Figure 6A The description of a plurality of first electrodes 204 and electrical paths 602 according to one or more embodiments of the present disclosure is as follows: Figure 2AA top view of part of sample 202. Specifically, Figure 6A The electrical path 602 is depicted as an electrical trace between the first electrode 204 of each of the blanks 208 and the sealing ring 212, and an electrical trace between the sealing ring 212 and the electrical grid 604 in the channel 210. In this way, the various first electrodes 204 across the blank 202 can all be electrically connected to each other. Furthermore, any of these electrical connection elements can form an electrical contact suitable for connection to the source 404. In some embodiments, although not shown in the figures, individual electrical contacts (e.g., conductive pads, etc.) can be fabricated.

[0080] Step 114, which involves fabricating one or more electrical paths 602 from the first electrode 204 to the electrical contacts, can be performed in any suitable sequence within method 100. In some embodiments, step 114 is performed concurrently with step 102, which involves fabricating the first electrode 204. For example, the electrical paths 602 can be provided in the fabrication design of one or more first electrodes 204.

[0081] In some embodiments, method 100 includes an electrical contact between the second electrode 402 and a connection to the first electrode 204 (e.g., Figure 6A Step 116 involves applying a voltage between any components electrically connected to the first electrode 204 to modify the orientation of the C-axis vector 304 of the piezoelectric material 302. For example, step 116 may be performed after step 108, which involves manufacturing the second electrode 402.

[0082] In some embodiments, method 100 includes step 118 of cutting off at least one of the electrical paths 602 after modifying the orientation of the C-axis vector 304 of the piezoelectric material 302. This allows the first electrode 204 (and more generally, the fully shaped resonator 200) to be connected in any suitable circuit design.

[0083] Step 118 can be performed using any technique known in the art suitable for disconnecting electrical connections between connecting components. In some embodiments, one or more of the electrical paths 602 may be accessible after depositing the piezoelectric material 302 and / or the second electrode 402. In these configurations, any suitable process may be used to cut the electrical path 602, including but not limited to applying mechanical force or etching. In some embodiments, one or more of the electrical paths 602 may be buried beneath one or more material layers (e.g., piezoelectric material 302, second electrode 402, etc.). In these configurations, any suitable process may be used to cut the electrical path 602, including but not limited to etching holes through the material layer above the electrical path 602 and further etching at least a portion of the electrical path 602 (e.g., using the same or different etchants).

[0084] As an explanation, Figure 6BA photomask 606 is depicted according to one or more embodiments of the present disclosure for etching at least through a piezoelectric material 302 containing various holes 608 to be etched, wherein at least some of the holes 608 are aligned with electrical paths 602 to be cut. Figure 6C A top view depicting a sample 202 according to one or more embodiments of the present disclosure, the depiction of which is derived from the use of Figure 6B The photomask 606 in the figure etches the cut-off electrical path 602. In addition, although not explicitly shown in the figure, when the fabricated die 208 is monolithized, the electrical path 602 between the dies 208 (e.g., but not limited to the electrical path 602 between the sealing ring 212 and the grid 604 or the grid 604 itself) can be cut off.

[0085] Generally refer to Figure 2 and Figures 6A to 6C It should be understood that Figure 2 and Figures 6A to 6C Provided for illustrative purposes only and should not be construed as limiting. For example, sample 202 may include any number, shape, or orientation of first electrodes 204 or electrical paths 602. Furthermore, sample 202 need not include all illustrative components, such as, but not limited to, the electrical grid 604 in the sealing ring 212 or channel 210.

[0086] For reference Figure 1D and Figures 7 to 8 The following describes in more detail the fabrication of a resonator 200 comprising a piezoelectric material 302 having a modified C-axis vector 304, according to one or more embodiments of the present disclosure. It is contemplated that method 100 enables the fabrication of a wide variety of resonator designs, wherein the piezoelectric material constituting the resonator can be fabricated under conditions suitable for high electromechanical coupling, and wherein any C-axis vector 304 constituting the piezoelectric material can subsequently be modified as required by a particular resonator design.

[0087] After modifying the C-axis vector 304 of the piezoelectric material 302, the second electrode 402 is as follows: Figure 5A and 5B As described, when fabricated on piezoelectric material 302, it can be at least partially retained and used as an operating component of resonator 200 or removed (e.g., as shown in the diagram). Figure 1B (as provided in step 112). In applications where the second electrode 402 is a separate component and is not fabricated as at least a temporary part of the layer of the resonator 200, only the second electrode 402 may be removed in subsequent steps.

[0088] In some embodiments, after modifying the C-axis vector 304 of the piezoelectric material 302, the second electrode 402 may form an operating component of the resonator 200.

[0089] For example, Figure 5A and 5BThe resonator 200 depicted, with the retained second electrode 402, can be an FBAR. In this way, Figure 5A and 5B The figure depicts FBAR resonators with different C-axis vectors 304 using the same manufacturing process for the piezoelectric material 302. Although not shown in the figure, the second electrode 402 may also be patterned before or after modifying the C-axis vector 304 of the piezoelectric material 302.

[0090] In some embodiments, one or more additional material layers are formed on the piezoelectric material 302 and optionally the second electrode 402. For example, one or more additional piezoelectric materials and one or more additional electrodes may be formed on the second electrode 402 to form a resonator 200 having a stacked structure, such as, but not limited to, DBAR, SBAR, or RSBAR. Stacked resonator designs are substantially described in U.S. Patent No. 7,889,024, published February 15, 2011; U.S. Patent No. 9,847,768, published December 19, 2017; and U.S. Patent Publication No. 2009 / 0079514, published March 26, 2019, the entire contents of all of these patents are incorporated herein by reference.

[0091] In some embodiments, the resonator 200 includes an additional piezoelectric material having a C-axis vector 304 oriented antiparallel to the first piezoelectric material 302. For example, the additional piezoelectric material may be manufactured using the same process as the first piezoelectric material 302 and may therefore have matching electromechanical properties but a different C-axis vector 304.

[0092] Figure 1D This is a flowchart depicting additional steps of a method 100 relating to the manufacture of a resonator 200 having a stacked structure according to one or more embodiments of the present disclosure.

[0093] In some embodiments, method 100 includes a step 120 of manufacturing additional piezoelectric material. Step 120 of manufacturing additional piezoelectric material can be performed using any technique known in the art, including but not limited to sputtering techniques. The additional piezoelectric material may have any C-axis vector 304 orientation, such as, but not limited to, an orientation antiparallel to a modified C-axis vector 304 of the piezoelectric material 302. For example, in which the second electrode 402 is formed as a layer (e.g., as... Figure 1B (As explained in the text) and in applications where the C-axis vector 304 is retained in whole or in part after modification, additional piezoelectric material may be fabricated on piezoelectric material 302 with or without an intervention layer. As another example, in applications where the second electrode 402 is removed or independent of the resonator 200, additional piezoelectric material may be fabricated on the second electrode 402 with or without an intervention layer.

[0094] In some embodiments, method 100 includes step 122 of fabricating a third electrode (e.g., on an additional piezoelectric material). For example, the third electrode may be fabricated to be in direct contact with the additional piezoelectric material. As another example, one or more intervening layers may be fabricated between the additional piezoelectric material and the third electrode. Thus, the third electrode may form another operating electrode of the resonator.

[0095] Figure 7 This is a simplified side view of a resonator 200 comprising two piezoelectric materials having antiparallel C-axis vectors 304 and an intermediate electrode, according to one or more embodiments of this disclosure. For example, Figure 7 The resonator 200 described herein can correspond to Figure 5B In addition, there is an extra piezoelectric material 702 and a third electrode 704. Therefore, Figure 5B The resonator 200 described herein can be characterized as two stacked FBARs having antiparallel C-axis vectors 304. In this configuration, the second electrode 402 is retained as an intermediate electrode, which can be adapted (but is not limited to) the operation of the resonator 200 in differential mode. Therefore, additional piezoelectric material 702 can be fabricated directly on the second electrode 402 or on one or more intervening layers.

[0096] Figure 8 This is a simplified side view of a resonator 200 comprising two piezoelectric materials having antiparallel C-axis vectors 304 and without an intermediate electrode, according to one or more embodiments of this disclosure. For example, Figure 8 The resonator 200 described herein may correspond to the resonator after the removal of the independent second electrode 402. Figure 4C Or after removing the second electrode 402 Figure 5B Therefore, the additional piezoelectric material 702 can be fabricated directly on the piezoelectric material 302 or on one or more intervention layers.

[0097] Figure 7 and 8 Further, non-limiting examples of the operation of resonator 200 are described. Specifically, Figure 7 and 8 A configuration is depicted in which a first electrode 204 is connected to ground and a source 706 is connected to a third electrode 704 to apply a signal (e.g., an RF signal) to the third electrode 704 relative to ground. In this configuration, the electric field 708 points in a common direction to both the piezoelectric material 302 and the additional piezoelectric material 702, while the C-axis vector 304 is antiparallel. However, it should be understood that the resonator 200 can be adapted to any configuration connection for the application, and the connections described herein are merely illustrative.

[0098] General reference Figure 7 and 8 It should be understood that Figure 7and 8 The descriptions and their associations are provided for illustrative purposes only and should not be construed as limiting. The resonator 200 may, in any arrangement, contain any number of piezoelectric materials, wherein the C-axis vector of at least one of the piezoelectric materials is modified by applying an electric field. Furthermore, this piezoelectric material having the modified C-axis vector may be fabricated at any location within the resonator 200.

[0099] For example, having such Figure 7 The resonator 200 with the final structure described herein can be formed by manufacturing a first electrode 204, a piezoelectric material 302, a second electrode 402, an additional piezoelectric material 702, and a third electrode 704 such that both the piezoelectric material 302 and the additional piezoelectric material 702 have an initial C-axis vector 304 oriented in the -Z direction. Subsequently, the C-axis vector 304 of the additional piezoelectric material 702 can be modified to the +Z direction by applying a voltage between the second electrode 402 and the third electrode 704.

[0100] As another example, the resonator 200 may comprise more than two piezoelectric layers, with or without intervening electrodes. In this way, the resonator 200, of any design, can be within the spirit and scope of this disclosure, wherein at least one constituting a piezoelectric layer is modified by applying an electric field.

[0101] This paper considers a resonator 200 having a stacked structure of two piezoelectric materials having opposite (e.g., antiparallel) C-axis vectors 304 (e.g., but not limited to) Figure 7 and 8 The description in the figure shows that such a design offers numerous advantages over alternative resonator designs. For illustration, such a design can present an alternative to multiple conventional FBAR devices connected in parallel (e.g., as illustrated in Figure 5).

[0102] For example, this design can advantageously suppress or otherwise cancel various harmonic resonance modes, including, but not limited to, second harmonic modes that may be undesirable in some applications. Specifically, the antiparallel orientation of the C-axis vector 304 constituting the piezoelectric material (e.g., piezoelectric material 302 and additional piezoelectric material 702) can result in more effective suppression of antiparallel oscillations of at least the second harmonic mode than in alternative designs.

[0103] As another example, this design allows for relatively thicker electrodes than conventional FBAR devices for a given operating frequency. Specifically, because the combined thickness of the piezoelectric layer (e.g., piezoelectric material 302 and additional piezoelectric material 702) of the resonator 200 disclosed herein is greater than (e.g., twice as thick) as the piezoelectric layer in a conventional FBAR device, relatively thicker electrodes are required to provide the same operating frequency as a conventional FBAR device.

[0104] This paper considers that the increased sheet resistance as electrodes become thinner is a significant factor in operating losses (e.g., attenuation). Therefore, relatively thick electrodes associated with this design promote a reduction in sheet resistance and associated losses for a specific operating frequency. Alternatively, relatively thick electrodes associated with this design can be efficiently scaled to higher frequency bands. For example, scaling a resonator design to higher frequencies typically involves reducing the thickness of, for example, the constituent materials of the electrodes. Besides sheet resistance losses, practical limitations on minimum electrode thickness also hinder high-frequency operation. However, the systems and methods disclosed herein enable scaling to higher frequencies than alternative designs. In some embodiments, the systems and methods disclosed herein are suitable for a resonator 200 operating at frequencies equal to or greater than 6 GHz, which is challenging for conventional designs. For example, this resonator 200 may have one or more resonant frequencies equal to or greater than 6 GHz. In this way, this resonator 200 can be used in filters or other circuits suitable for receiving signals with frequencies equal to or greater than 6 GHz.

[0105] Furthermore, the systems and methods disclosed herein offer various advantages over resonators of similar design manufactured using different techniques. For example, techniques for manufacturing a resonator 200 with opposite C-axis vectors 304 (e.g., but not limited to...) Figure 7 and 8 The technique described herein, which involves directly manufacturing a piezoelectric layer with opposite C-axis vectors 304, is subject to mismatches in electromechanical and / or thermal properties or inconsistent manufacturing quality between different processes.

[0106] Conversely, the systems and methods disclosed herein facilitate the fabrication of multiple piezoelectric materials (described herein as piezoelectric material 302 and additional piezoelectric material 702) through a common manufacturing process to provide an initial C-axis vector 304 along a common direction. In this manner, the orientation of the initial C-axis vector 304 and / or the manufacturing process of the piezoelectric material can be selected to provide desired properties, such as, but not limited to, electromechanical or thermal properties. Furthermore, the various properties of different piezoelectric layers can be effectively matched to efficiently suppress undesirable harmonics.

[0107] For reference Figure 9This document describes in more detail a circuit comprising one or more resonators 200 according to one or more embodiments of the present disclosure. It is contemplated that one or more resonators 200 having a modified C-axis vector 304 can be used in any suitable type of circuit (e.g., a circuitry) suitable for any application, including but not limited to filters, RF communication systems, or sensors. In this way, a circuit may include at least one resonator 200 having a modified C-axis vector 304 and any number of additional components, including but not limited to additional resonators manufactured using other techniques, passive components (e.g., resistors, capacitors, inductors, etc.) or active components (e.g., amplifiers, etc.).

[0108] Figure 9 This is a simplified schematic diagram of a filter 902 comprising a plurality of resonators 200 according to one or more embodiments of the present disclosure, wherein at least one of the resonators has a modified C-axis vector 304. Specifically, Figure 9 A filter 902 is depicted comprising two series resonators 904 and a parallel resonator 906. For example, the series resonators 904 are connected in series between input terminal 908 and output terminal 910, while the parallel resonator 906 is connected between ground and a node between any of the series resonators 904. This document considers that the filter 902 may operate as a bandpass filter or a band-stop filter (e.g., notch filter, band-stop filter, etc.) depending on the resonant frequency of the parallel resonator 906. In some embodiments, the filter 902 includes at least one resonator 200 having at least one piezoelectric material 302 containing a modified C-axis vector 304. For example, in… Figure 9 In this configuration, the series resonator 904 and the parallel resonator 906 are all formed as a resonator 200 having at least one piezoelectric material 302 containing a modified C-axis vector 304.

[0109] It should be understood that Figure 9 The descriptions and related information are provided for illustrative purposes only and should not be construed as limiting. For example, filter 902 may comprise any number of series resonators 904 or parallel resonators 906. More generally, at least one resonator 200 having at least one piezoelectric material 302 with a modified C-axis vector 304 as disclosed herein can be implemented within any filter design, including but not limited to trapezoidal or lattice designs. Furthermore, the resonator 200 disclosed herein can be implemented within any filter that provides any type of filtered response, such as, but not limited to, low-pass, high-pass, band-pass, or band-reject filters.

[0110] In some embodiments, the filter 902 comprises a stacked structure of two piezoelectric materials formed having antiparallel C-axis vectors 304 as disclosed herein (e.g., as...). Figure 7 and 8At least one resonator 200 (described herein). As previously described, this resonator 200 can advantageously provide efficient mitigation of desired electromechanical coupling properties, thermal characteristics, and / or harmonic resonance modes (e.g., second-order resonance modes). Additionally, this resonator 200 can provide relatively thicker electrodes than alternative resonator designs (e.g., single FBAR designs, etc.), which can advantageously provide relatively low sheet resistance and further enable operation at relatively high frequencies (e.g., but not limited to 6 GHz and above). Therefore, a filter 902 including one or more such resonators 200 can operate at frequencies equal to or greater than 6 GHz and provide relatively low losses. For example, for signals with frequencies equal to or greater than 6 GHz, this filter 902 can have a well-defined frequency response. As an illustration, a filter 902 configured as a bandpass filter can have a passband covering frequencies equal to or greater than 6 GHz. As another illustration, a filter 902 configured as a bandstop filter can have a stopband covering frequencies equal to or greater than 6 GHz. Similarly, the filter 902 configured as low-pass and / or high-pass may have a well-defined frequency response for frequencies equal to or greater than 6 GHz (e.g., a passband or stopband with selected transmittance).

[0111] In some embodiments, a filter 902 comprising at least one resonator 200 as disclosed herein is implemented within an RF communication system. For example, a filter 902 comprising at least one resonator 200 as disclosed herein is implemented in the transmission path of an RF communication system. In this manner, the relatively low loss of the filter 902 provided by the resonator 200 as disclosed herein can facilitate a relatively high transmission distance. As another example, a filter 902 comprising at least one resonator 200 as disclosed herein is implemented in the receiving path of an RF communication system. In this manner, the relatively low loss of the filter 902 provided by the resonator 200 as disclosed herein can facilitate a relatively low noise figure.

[0112] The topics described herein sometimes illustrate different components contained within or connected to other components. It should be understood that the architectures depicted are merely exemplary, and many other architectures can in fact be implemented to achieve the same functionality. Conceptually, any arrangement of components that achieve the same functionality is effectively “associated” with each other to achieve the desired functionality. Therefore, any two components combined herein to achieve a particular functionality can be considered “associated” with each other to achieve the desired functionality, regardless of the architecture or intermediate components. Similarly, any two such associated components can also be considered “connected” or “coupled” with each other to achieve the desired functionality, and any two components that can be suchly associated can also be considered “coupled” with each other to achieve the desired functionality. Specific examples of couplerability include, but are not limited to, physically interactive and / or physically interactive components and / or wirelessly interactive and / or logically interactive components.

[0113] It is believed that this disclosure and its many accompanying advantages will be understood from the foregoing description, and it will be apparent that various changes can be made to the form, construction, and arrangement of the components without departing from the disclosed subject matter or sacrificing all its material advantages. The forms described are merely illustrative, and the appended claims are intended to cover and encompass such changes. Furthermore, it should be understood that the invention is defined by the appended claims.

Claims

1. A resonator comprising: First electrode; Second electrode; as well as The piezoelectric material between the first electrode and the second electrode, wherein the piezoelectric material is formed by the following operation: The piezoelectric material is manufactured having a compression axis vector oriented along a first direction, the piezoelectric material being doped with one or more dopant materials, the one or more dopant materials being selected to reduce the electric field strength used to modify the compression axis vector to a value range below the breakdown threshold. and An electric field is applied across the piezoelectric material to modify the orientation of the compression axis vector to be oriented along a second direction, wherein the second direction is antiparallel to the first direction.

2. The resonator according to claim 1, further comprising: An additional piezoelectric material having an additional compression axis vector oriented along the first direction, wherein the piezoelectric material and the additional piezoelectric material are disposed between the first electrode and the second electrode.

3. The resonator according to claim 2, further comprising: A third electrode is disposed between the piezoelectric material and the additional piezoelectric material.

4. The resonator according to claim 1, wherein the piezoelectric material comprises: A substrate material, which is doped with one or more of the aforementioned dopant materials.

5. The resonator of claim 4, wherein the substrate material comprises aluminum nitride, and wherein the one or more dopant materials comprise at least one of rare earth metals or boron.

6. The resonator of claim 4, wherein the substrate material comprises aluminum nitride, and wherein the one or more dopant materials comprise scandium at a concentration of less than about 35%.

7. The resonator of claim 1, wherein the resonator operates at a frequency equal to or greater than 6 GHz.

8. The resonator of claim 1, wherein applying the electric field across the piezoelectric material to modify the direction of the compression axial quantity from the first direction to the second direction comprises: Create one or more electrical paths from the first electrode to the electrical contact; A voltage is applied between the electrical contact and at least one of the second electrode or the additional electrode to generate the electric field; as well as Disconnect at least one of the one or more electrical paths.

9. A circuit comprising: One or more resonators, wherein at least one of the one or more resonators comprises: First electrode; The second electrode; and The piezoelectric material between the first electrode and the second electrode, wherein the piezoelectric material is formed by the following operation: Manufacturing the piezoelectric material having a compression axial amount oriented along a first direction; and An electric field is applied across the piezoelectric material to modify the orientation of the compression axis vector to be oriented along a second direction, wherein the second direction is different from the first direction; The piezoelectric material is doped with one or more dopant materials, which are selected to reduce the electric field strength used to modify the compression axis vector to a value range below the breakdown threshold.

10. The circuit of claim 9, wherein the circuit comprises: filter.

11. The circuit of claim 10, wherein the filter operates at a frequency equal to or greater than 6 GHz.

12. The circuit according to claim 9, further comprising: An additional piezoelectric material having an additional compression axis vector oriented along the first direction, wherein the piezoelectric material and the additional piezoelectric material are disposed between the first electrode and the second electrode.

13. The circuit of claim 12, further comprising: A third electrode is disposed between the piezoelectric material and the additional piezoelectric material.

14. The circuit of claim 9, wherein the piezoelectric material comprises: A substrate material, which is doped with one or more of the aforementioned dopant materials.

15. The circuit of claim 14, wherein the substrate material comprises aluminum nitride, and wherein the one or more dopant materials comprise at least one of rare earth metals or boron.

16. The circuit of claim 14, wherein the substrate material comprises aluminum nitride, and wherein the one or more dopant materials comprise scandium at a concentration of less than about 35%.

17. A method comprising: Manufacturing the first electrode; Manufacturing a piezoelectric material having a compression axial amount oriented along a first direction; An electric field is applied across the piezoelectric material to modify the direction of the compression axis vector from the first direction to a second direction, wherein the second direction is antiparallel to the first direction; as well as A second electrode is manufactured, wherein the piezoelectric material is disposed between the first electrode and the second electrode; The piezoelectric material is doped with one or more dopant materials, which are selected to reduce the electric field strength used to modify the compression axis vector to a value range below the breakdown threshold.

18. The method of claim 17, further comprising: An additional piezoelectric material is manufactured having an additional amount of axial compression oriented along the first direction.

19. The method of claim 18, further comprising: A third electrode is manufactured, wherein the additional piezoelectric material is disposed between the second electrode and the third electrode.

20. The method of claim 18, wherein the piezoelectric material and the additional piezoelectric material are disposed between the first electrode and the second electrode.

Images