Resonator with common reflector

Abstract

The present invention relates to a resonator having a common reflector, and more particularly, to a resonator having a common reflector which forms a common reflector sharing a reflector of one resonator with a reflector of another resonator in a surface acoustic wave device having a plurality of resonators, therefore, the area required for forming the resonator on the substrate is reduced. In order to solve the technical problem, a resonator having a common reflector according to the present invention may comprise: first to n-th I DT electrode parts (n is a natural number of 3 or more) formed on a piezoelectric substrate and formed side by side in a first direction; first to (n-1)-th common reflectors formed between the first to n-th I DT electrode portions, respectively, and shared between two adjacent I DT electrode portions among the first to n-th I DT electrode portions; and a first reflector and an nth reflector formed on opposite sides of the common reflector so as to be aligned with the first and nth IDT electrode portions.

Description

Technical Field

[0001] The present invention relates to a resonator having a common reflector, and more particularly to a resonator having a common reflector that forms a common reflector that shares a reflector of one resonator and a reflector of another resonator in a surface acoustic wave device having a plurality of resonators, thereby reducing the area required to form the resonators on a substrate. Background Art

[0002] Surface Acoustic Wave (SAW) refers to a wave that propagates along the surface of an elastic solid. The energy of this elastic surface wave is concentrated and propagated near the surface, which is equivalent to a mechanical wave. A surface acoustic wave element is an electromechanical element that utilizes the interaction between such a surface acoustic wave and semiconductor conductive electrons, and utilizes a surface acoustic wave that propagates on the surface of a piezoelectric crystal. Such surface acoustic wave elements can have a very wide range of application fields in industries such as sensors, oscillators, and filters, and can be miniaturized and lightweight, having various advantages such as robustness, stability, sensitivity, low cost, and real-time performance.

[0003] Figure 1 is a plan view of a resonator.

[0004] Referring to Figure 1 , the resonator is configured to form an IDT (Inter Digital Transducer) electrode portion 150 that converts an electrical signal into a surface acoustic wave of the piezoelectric substrate 100 on the piezoelectric substrate 100, and reflectors 180A and 180B are respectively formed at both end portions of the IDT electrode portion 150 to prevent the surface acoustic wave energy generated by the IDT electrode portion 150 from leaking or attenuating from the IDT electrode portion 150, and to enclose the surface acoustic wave energy within the IDT electrode portion 150.

[0005] The IDT electrode portion 150 includes: a first bus bar 120 and a second bus bar 125 that extend along a first direction and are spaced apart from each other in a second direction perpendicular to the first direction; a first IDT electrode 130 and a second IDT electrode 135 that alternately extend from the first bus bar 120 and the second bus bar 125 in the second direction and are spaced apart from each other in the first direction.

[0006] The reflectors 180A and 180B include: a pair of reflector bus bars 170 that extend along a first direction and are spaced apart from each other in a second direction perpendicular to the first direction; a plurality of reflector electrodes 175 that connect the reflector bus bars 170 in the second direction and are spaced apart from each other in the first direction.

[0007] One or more connected resonators 110 can form a surface acoustic wave filter for an electronic device.

[0008] When a surface acoustic wave filter is formed by a plurality of resonators 110, the reflectors 180A and 180B formed on the resonators 110 must all be formed on each resonator 110, so the space occupied on the piezoelectric substrate 100 increases, thus limiting the miniaturization of the surface acoustic wave filter.

[0009] Therefore, there is a need to develop a technology that can both miniaturize the size of a surface acoustic wave resonator or a surface acoustic wave filter and maintain its performance. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to provide a resonator with a common reflector, which reduces the area occupied on the piezoelectric substrate by the reflectors formed at both end portions of the IDT electrode portion in order to enclose the surface acoustic wave energy within the IDT electrode portion, thereby enabling miniaturization of the surface acoustic wave resonator or the surface acoustic wave filter.

[0011] The technical problem of the present invention is not limited to the above-mentioned technical problems, and those skilled in the art can clearly understand other technical problems not mentioned from the following description.

[0012] To solve the above technical problems, the resonator with a common reflector of the present invention may include: a first IDT electrode portion and a second IDT electrode portion, which are formed on a piezoelectric substrate and are formed side by side along a first direction; a common reflector, which is formed between the first IDT electrode portion and the second IDT electrode portion and is shared by the first IDT electrode portion and the second IDT electrode portion; and a first reflector and a second reflector, which are formed on the opposite side of the common reflector in a form side by side with the first IDT electrode portion and the second IDT electrode portion.

[0013] In some embodiments of the present invention, when the number of reflector electrodes of the first IDT electrode portion before forming the common reflector is referred to as N1, and the number of reflector electrodes of the second IDT electrode portion is referred to as N2, then the number of reflector electrodes Ns of the first common reflector may satisfy the condition of Min(N1, N2) ≤ Ns ≤ (N1 + N2).

[0014] In some embodiments of the present invention, assuming that the second-direction length of the reflector of the first IDT electrode portion before forming the common reflector is referred to as H1, the second-direction length of the reflector of the second IDT electrode portion is referred to as H2, and assuming that the second-direction length of the common reflector is referred to as HS, then the condition of Max(H1, H2) ≤ HS may be satisfied.

[0015] In some embodiments of the present invention, when the distance between the IDT electrodes of the first IDT electrode portion is referred to as T1 and the distance between the IDT electrodes of the second IDT electrode portion is referred to as T2, the distance TS1 between the reflector electrodes of the common reflector may satisfy the condition of Max(T1, T2) ≤ TS1.

[0016] To solve the above technical problems, the resonator with a common reflector of the present invention may include: first to nth IDT electrode portions (n is a natural number of 3 or more), which are formed on a piezoelectric substrate and arranged side by side in a first direction; first to (n - 1)th common reflectors, which are respectively formed between the first to nth IDT electrode portions and shared between two adjacent IDT electrode portions among the first to nth IDT electrode portions; and a first reflector and an nth reflector, which are formed on the opposite side of the common reflector in a form arranged side by side with the first IDT electrode portion and the nth IDT electrode portion.

[0017] In some embodiments of the present invention, when the number of electrodes of the reflector of the (n - 1)th electrode portion before forming the (n - 1)th common reflector is referred to as Nn - 1 and the number of reflector electrodes of the nth IDT electrode portion is referred to as Nn, the number Ns of the reflector electrodes of the (n - 1)th common reflector may satisfy the condition of Min(Nn - 1, Nn) ≤ Ns ≤ (Nn - 1 + Nn).

[0018] In some embodiments of the present invention, assuming that the second - direction length of the reflector of the (n - 1)th IDT electrode portion before forming the (n - 1)th common reflector is referred to as Hn - 1, the second - direction length of the reflector of the nth IDT electrode portion is referred to as Hn, and assuming that the second - direction length of the (n - 1)th common reflector is referred to as HSn - 1, the condition of Max(Hn - 1, Hn) ≤ HSn - 1 may be satisfied.

[0019] In some embodiments of the present invention, when the distance between the IDT electrodes of the (n - 1)th IDT electrode portion is referred to as Tn - 1 and the distance between the IDT electrodes of the nth IDT electrode portion is referred to as Tn, the distance TSn - 1 between the reflector electrodes of the common reflector may satisfy the condition of Max(Tn - 1, Tn) ≤ TSn - 1.

[0020] In some embodiments of the present invention, the electrode portion may include: a first bus bar and a second bus bar, which extend in a first direction and are spaced apart from each other in a second direction perpendicular to the first direction; a first IDT electrode and a second IDT electrode, which extend alternately in the second direction from the first bus bar and the second bus bar and are spaced apart from each other in the first direction.

[0021] In some embodiments of the present invention, the reflector may include: a pair of reflector buses extending in a first direction and spaced apart from each other in a second direction perpendicular to the first direction; and a plurality of reflector electrodes connecting the reflector buses in the second direction and spaced apart from each other in the first direction, respectively.

[0022] In a resonator having a common reflector according to the present invention, a common reflector that shares the reflector of one resonator with the reflector of another resonator is formed in a surface acoustic wave device having a plurality of resonators, so that the four reflectors formed in two resonators can be reduced to three, and the 2n reflectors formed in n resonators can be reduced to n + 1, thereby reducing the area required to form the resonators on the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a plan view of a resonator.

[0024] FIG. 2 is a plan view showing a surface acoustic wave resonator according to an embodiment of the present invention.

[0025] FIG. 3 is a plan view showing a surface acoustic wave resonator with different apertures according to an embodiment of the present invention.

[0026] FIG. 4 is a plan view showing a surface acoustic wave resonator with different electrode spacings according to an embodiment of the present invention.

[0027] Figure 5 is a diagram showing the electrode spacing according to FIG. 4.

[0028] FIG. 6 is a plan view showing a surface acoustic wave resonator according to another embodiment of the present invention.

[0029] FIG. 7 is a plan view showing a surface acoustic wave resonator with different apertures according to another embodiment of the present invention.

[0030] FIG. 8 is a plan view showing a surface acoustic wave resonator with different electrode spacings according to another embodiment of the present invention.

[0031] Figure 9 is a diagram showing the electrode spacing according to FIG. 8.

[0032] REFERENCE NUMERAL DESCRIPTION

[0033] 100: Piezoelectric substrate

[0034] 110: Resonator

[0035] 111: First resonator

[0036] 112: Second resonator

[0037] 116: The (n - 1)th resonator

[0038] 117: The nth resonator

[0039] 120: The first bus bar

[0040] 125: The second bus bar

[0041] 130: The first IDT electrode

[0042] 135: The second IDT electrode

[0043] 150: The IDT electrode section

[0044] 151: The first IDT electrode section

[0045] 152: The second IDT electrode section

[0046] 156: The (n - 1)th IDT electrode section

[0047] 157: The nth IDT electrode section

[0048] 170: The reflector bus bar

[0049] 175: The reflector electrode

[0050] 180A, 180B: The reflector

[0051] 181A, 181B: The first reflector

[0052] 182A, 182B: The second reflector

[0053] 186A, 186B: The (n - 1)th reflector

[0054] 187A, 187B: The nth reflector

[0055] 191: The first common reflector

[0056] 196: The (n - 1)th common reflector DETAILED DESCRIPTION

[0057] Advantages, features, and methods for realizing them of the present invention will become clear when referring to the accompanying drawings and the embodiments described in detail below. However, the present invention is not limited to the embodiments disclosed below, but is implemented in various different forms. The present embodiments are provided to ensure the completeness of the disclosure of the present invention and to fully inform those with ordinary knowledge in the technical field to which the present invention pertains of the scope of the invention. The present invention is only defined by the scope of the claims. Throughout the specification, the same reference numerals represent the same components.

[0058] "and / or" includes each and all combinations of the items mentioned.

[0059] The terms used in this specification are for the purpose of describing embodiments and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated in the sentence. When the specification uses "comprising" and / or "comprising..." to refer to components, steps, actions, and / or elements, it does not exclude the existence or addition of one or more other components, steps, actions, and / or elements.

[0060] In addition, throughout the specification, when a part is "connected" to another part, it includes not only the case of "directly connected", but also the case of "indirectly" or "electrically connected" with other components or elements intervening therebetween.

[0061] In addition, throughout the specification, the description that each layer (film), region, pattern, or structure is formed "on / above (on)" or "under / below (under)" the substrate, each side (film), region, spacer, or pattern includes being formed directly (directly) or being formed with other layers intervening. The reference for the above / above or below / below of each layer is described based on the drawings.

[0062] In addition, expressions such as "first", "second", etc. are only used to distinguish multiple components and do not limit the order or other characteristics between the components.

[0063] Unless otherwise defined, any terms (including technical terms and scientific terms) used in this specification can be used as the meanings commonly understood by those with ordinary knowledge in the technical field to which the present invention pertains. In addition, terms defined in commonly used dictionaries will not be ideally or overly interpreted unless there is an obvious special definition.

[0064] The present invention will be described in detail with reference to the accompanying drawings.

[0065] FIG. 2 is a plan view showing a surface acoustic wave resonator according to an embodiment of the present invention, where (a) shows that two resonators are formed separately, and (b) shows that two resonators share a common reflector.

[0066] Referring to FIG. 2(b), a surface acoustic wave resonator according to an embodiment of the present invention may include: a first IDT electrode portion 151 and a second IDT electrode portion 152, which are formed on a piezoelectric substrate 100 and are formed side by side in a first direction; a common reflector 191, which is formed between the first IDT electrode portion 151 and the second IDT electrode portion 152 and is shared by the first IDT electrode portion 151 and the second IDT electrode portion 152; a first reflector 181A and a second reflector 182B, which are formed on the opposite side of the common reflector 191 in a form side by side with the first IDT electrode portion 151 and the second IDT electrode portion 152.

[0067] The piezoelectric substrate 100 may be a multilayer substrate including a plurality of layers. The plurality of layers may include, for example, a support substrate containing silicon and a piezoelectric layer containing substances such as LiTaO3 (LT) and LiNbO3 (LN) located on the upper part.

[0068] The IDT electrode portion 150 may include: a first bus bar 120 and a second bus bar 125, which extend along a first direction and are spaced apart from each other in a second direction perpendicular to the first direction; a first IDT electrode 130 and a second IDT electrode 135, which alternately extend from the first bus bar 120 and the second bus bar 125 in the second direction and are spaced apart from each other in the first direction respectively.

[0069] The reflector may include: a pair of reflector bus bars 170, which extend along a first direction and are spaced apart from each other in a second direction perpendicular to the first direction; a plurality of reflector electrodes 175, which connect the reflector bus bars 170 in the second direction and are spaced apart from each other in the first direction respectively.

[0070] The first electrode portion 151, the second IDT electrode portion 152, and the reflectors 181A, 182B, 191 may be formed of a single-layer metal film or a laminated metal film, and may be formed simultaneously by the same process, for example, a deposition process.

[0071] Referring to Fig. 2(a), two first reflectors 181B on the right side of the first IDT electrode portion 151 in the first direction and second reflectors 181A on the left side of the second IDT electrode portion 152 in the first direction are separately separated on the piezoelectric substrate 100. However, referring to Fig. 2(b), the first reflector 181B and the second reflector 181A may be shared and merged to form a first common reflector 191. As described above, the area of the piezoelectric substrate 100 may be reduced by the area of one reflector.

[0072] At this time, if the number of electrodes of the first reflector 181B of the first IDT electrode portion 151 before forming the common reflector is called N1, and the number of electrodes of the second reflector 182A of the second IDT electrode portion 152 is called N2, then the number of electrodes Ns of the first common reflector 191 may satisfy the condition of Min(N1, N2) ≤ Ns ≤ (N1 + N2).

[0073] In other words, the number of electrodes of the common reflector may be equal to or more than the smaller number of electrodes of the two reflectors arranged on both sides of the common reflector, and may be equal to or less than the sum of the number of electrodes of the two reflectors arranged on both sides.

[0074] When formed as described above and measuring the characteristics of the resonator such as the frequency characteristics and insertion loss before and after sharing the reflector, it can be confirmed that the characteristics will not be reduced even if the reflector is shared.

[0075] FIG. 3 is a plan view showing surface acoustic wave resonators in the case of different apertures according to an embodiment of the present invention. (a) shows that two resonators are respectively formed, and (b) shows that the two resonators share a common reflector.

[0076] When the second-direction lengths of the reflectors 181A and 181B of the first electrode portion 151 before forming the common reflector 191 are referred to as H1, and the second-direction lengths of the reflectors 182A and 182B of the second IDT electrode portion 152 are referred to as H2, the length of the common reflector 191 in the second direction can satisfy the condition of Max(H1, H2) ≤ HS.

[0077] In other words, in the case of two resonators with different apertures, the length of the common reflector can be greater than or equal to the length of the reflector of the resonator with the larger aperture among the two resonators.

[0078] The aperture is the interval where the first IDT electrode 130 and the second IDT electrode 135 cross, and surface acoustic waves are mainly transmitted within this interval, so it is the part that determines the characteristics of the resonator. When the aperture is larger, the lengths of the IDT electrode portion and the reflector in the second direction increase proportionally.

[0079] When formed as described above and measuring the characteristics of the resonator such as the frequency characteristics and insertion loss before and after sharing the reflector, it can be confirmed that the characteristics are not degraded even when sharing the reflector.

[0080] FIG. 4 is a plan view showing surface acoustic wave resonators in the case of different electrode distances according to an embodiment of the present invention. (a) shows that two resonators are respectively formed, and (b) shows that the two resonators share a common reflector.

[0081] Referring to FIG. 4(b), when the distance between the IDT electrodes 130 and 135 of the first IDT electrode portion 151 is referred to as T1, and the distance between the IDT electrodes 130 and 135 of the second IDT electrode portion 152 is referred to as T2, the distance TS1 between the reflector electrodes of the first common reflector 191 can satisfy the condition of Max(T1, T2) ≤ TS1.

[0082] In other words, the distance between the electrodes of the common reflector can be greater than the longer one of the distances between the two IDT electrodes disposed on both sides of the common reflector.

[0083] Figure 5 It is a diagram showing the electrode distance according to FIG. 4.

[0084] Referring to Figure 5, it can be confirmed that the length (TS1) between the electrodes of the first common reflector 191 is greater than the longer one of the length (T1) between the electrodes of the first IDT electrode portion 151 disposed on both sides of the first common reflector 191 and the length (T2) between the electrodes of the second IDT electrode portion 152.

[0085] When formed as described above and measuring the characteristics of the resonator such as the frequency characteristics and insertion loss before and after the shared reflector, it can be confirmed that even the shared reflector does not degrade the characteristics.

[0086] Hereinafter, another embodiment of the present invention will be described with reference to the drawings.

[0087] FIG. 6 is a plan view showing a surface acoustic wave resonator according to another embodiment of the present invention, where (a) shows that n resonators are formed separately, and (b) shows that n resonators share a common reflector.

[0088] Referring to FIG. 6(b), a surface acoustic wave resonator according to another embodiment of the present invention may include: first to nth IDT electrode portions 151, 157 formed on a piezoelectric substrate 100 and arranged side by side in a first direction; first to (n - 1)th common reflectors 191 to 196 respectively formed between the first to nth IDT electrode portions 151, 157 and shared between two adjacent IDT electrode portions among the first to nth IDT electrode portions 151, 157; a first reflector 181A and an nth reflector 187B formed on the opposite side of the common reflector in a form arranged side by side with the first IDT electrode portion 151 and the nth IDT electrode portion 157. Here, n represents a natural number of 3 or more.

[0089] The piezoelectric substrate 100 may be a multilayer substrate including a plurality of layers. The plurality of layers may include, for example, a support substrate containing silicon and a piezoelectric layer containing substances such as LiTaO3 (LT) and LiNbO3 (LN) located on the upper part.

[0090] The first to nth IDT electrode portions 151... 157 may include: a first bus bar 120 and a second bus bar 125 extending in the first direction and spaced apart from each other in a second direction perpendicular to the first direction; a first IDT electrode 130 and a second IDT electrode 135 extending alternately in the second direction from the first bus bar 120 and the second bus bar 125 and spaced apart from each other in the first direction respectively.

[0091] The reflector may include: a pair of reflector bus bars 170 extending in the first direction and spaced apart from each other in a second direction perpendicular to the first direction; a plurality of reflector electrodes 175 extending in the second direction and spaced apart from each other in the first direction respectively.

[0092] The first to nth IDT electrode portions 151…157 and the reflectors 181A, 182B, 191 may be formed of a single-layer metal film or a laminated metal film, and may be formed simultaneously by the same process, for example, a deposition process.

[0093] Referring to Fig. 6(a), a first reflector 181A on the left side in the first direction and a first reflector 181B on the right side are formed on both sides of the first IDT electrode portion 151; an (n - 1)th reflector 186A on the left side in the first direction and an (n - 1)th reflector 186B on the right side are formed on both sides of the (n - 1)th IDT electrode portion 156, and an nth reflector 186A on the left side in the first direction and an nth reflector 186B on the right side are formed on both sides of the nth IDT electrode portion 156, and a total of 2n are formed in sequence. An additional IDT electrode portion may be formed between the first IDT electrode portion 151 and the (n - 1)th IDT electrode portion 156. Hereinafter, referring to Fig. 6(b), the first reflector 181B and the second reflector 181A are combined into one to form a shared first common reflector 191, and the reflectors between the respective IDT electrode portions formed in the middle may also be combined into one and shared. Finally, the (n - 1)th reflector 186B and the nth reflector 187A are combined to share an (n - 1)th common reflector 196.

[0094] When comparing the number of reflectors before and after sharing, 2n reflectors are required before sharing, but after sharing, it can be reduced to n + 1, which is the sum of n - 1 common reflectors and two outermost reflectors. As described above, the number of reflectors is reduced by n - 1, and the area of the piezoelectric substrate 100 can be reduced by the area corresponding to the reduced number.

[0095] At this time, when the number of electrodes of the reflector of the (n - 1)th electrode portion 156 before forming the (n - 1)th common reflector 196 is referred to as Nn - 1, and the number of electrodes of the reflector of the nth IDT electrode portion 157 is referred to as Nn, the number of electrodes Ns of the reflector of the (n - 1)th common reflector 196 may satisfy the condition of Min(Nn - 1, Nn) ≤ Ns ≤ (Nn - 1 + Nn).

[0096] In other words, the number of electrodes of the common reflector may be equal to or more than the smaller number of electrodes of the two reflectors disposed on both sides of the common reflector, and may be equal to or less than the sum of the number of electrodes of the two reflectors disposed on both sides.

[0097] When formed as described above and measuring the characteristics of the resonator such as the frequency characteristics and insertion loss before and after sharing the reflector, it can be confirmed that the characteristics will not be degraded even when sharing the reflector.

[0098] FIG. 7 is a plan view showing surface acoustic wave resonators in the case of different apertures according to another embodiment of the present invention. (a) shows that n resonators are formed separately, and (b) shows that n resonators share a common reflector.

[0099] When the second-direction length of the reflector of the (n - 1)th electrode portion 156 before forming the (n - 1)th common reflector 196 is denoted as Hn-1, and the second-direction length of the reflector of the nth IDT electrode portion 157 is denoted as Hn, then the second-direction length HSn-1 of the (n - 1)th common reflector 196 can satisfy the condition of Max(Hn-1, Hn) ≤ HSn-1.

[0100] In other words, in the case of two resonators with different apertures, the length of the common reflector can be greater than or equal to the length of the reflector of the resonator with the larger aperture among the two resonators.

[0101] The aperture is the interval where the first IDT electrode 130 and the second IDT electrode 135 cross, and surface acoustic waves are mainly transmitted in this interval. Therefore, it is the part that determines the characteristics of the resonator. When the aperture is larger, the second-direction lengths of the IDT electrode portion and the reflector increase proportionally.

[0102] When formed as described above and measuring the characteristics of the resonator such as the frequency characteristics and insertion loss before and after sharing the reflector, it can be confirmed that the characteristics are not degraded even when sharing the reflector.

[0103] FIG. 8 is a plan view showing surface acoustic wave resonators in the case of different electrode widths according to another embodiment of the present invention. (a) shows that n resonators are formed separately, and (b) shows that n resonators share a common reflector.

[0104] Referring to FIG. 8(b), when the distance between the IDT electrodes 130 and 135 of the (n - 1)th IDT electrode portion 156 is denoted as Tn-1, and the distance between the IDT electrodes 130 and 135 of the nth IDT electrode portion 157 is denoted as Tn, then the distance TSn-1 between the reflector electrodes of the (n - 1)th common reflector 196 can satisfy the condition of Max(Tn-1, Tn) ≤ TSn-1.

[0105] In other words, the distance between the electrodes of the common reflector can be greater than or equal to the longer one of the distances between the two IDT electrodes disposed on both sides of the common reflector.

[0106] Figure 9 It is a diagram showing the electrode distance according to FIG. 8.

[0107] Referring to Figure 9, it can be confirmed that the length (TSn-1) between the electrodes of the (n-1)th common reflector 196 is greater than the longer one of the length (Tn-1) between the electrodes of the (n-1)th IDT electrode part 156 disposed on both sides of the (n-1)th common reflector 196 and the length (Tn) between the electrodes of the (n-1)th IDT electrode part 157, and although Figure 9 is not shown in the diagram of, the length (TSn-1) between the electrodes of the (n-1)th common reflector 196 may also be the same as the longer one of the length (Tn-1) between the electrodes of the (n-1)th IDT electrode part 156 disposed on both sides of the (n-1)th common reflector part 196 and the length (Tn) between the electrodes of the (n)th IDT electrode part 157.

[0108] When formed as described above and measuring the characteristics of the resonator such as the frequency characteristics and insertion loss before and after the shared reflector, it can be confirmed that even the shared reflector does not degrade the characteristics.

[0109] Although the present invention has been described as above, those with ordinary knowledge in the technical field to which the present invention pertains can recognize that it can be implemented in other forms while maintaining the technical idea and essential features of the present invention.

[0110] Although the scope of rights of the present invention is basically determined by the patent claims, it should be interpreted that all configurations directly derived from the matters described in the patent claims and all changes or deformations derived from equivalent configurations are included within the scope of rights of the present invention.

Claims

1. A resonator with a common reflector, characterized in that include: A first IDT electrode portion and a second IDT electrode portion, which are formed on the piezoelectric substrate and are formed side by side along a first direction; a common reflector formed between the first IDT electrode portion and the second IDT electrode portion and shared by the first IDT electrode portion and the second IDT electrode portion; as well as The first reflector and the second reflector are formed on opposite sides of the common reflector in a manner parallel to the first IDT electrode portion and the second IDT electrode portion.

2. The resonator with a common reflector according to claim 1, characterized in that The first IDT electrode portion and the second IDT electrode portion include: A first bus bar and a second bus bar extending along a first direction and spaced apart from each other along a second direction perpendicular to the first direction; The first IDT electrodes and the second IDT electrodes are alternately extended from the first bus bar and the second bus bar along the second direction and are spaced apart from each other along the first direction.

3. The resonator with a common reflector according to claim 1, characterized in that Reflectors include: a pair of reflector busbars extending along a first direction and spaced apart from each other along a second direction perpendicular to the first direction; A plurality of reflector electrodes are elongated along the second direction and are spaced apart from each other along the first direction.

4. The resonator with a common reflector according to claim 1, characterized in that When the number of reflector electrodes of the first IDT electrode portion before forming a common reflector is called N1, and the number of reflector electrodes of the second IDT electrode portion is called N2, the number Ns of reflector electrodes of the first common reflector satisfies the condition Min(N1, N2)≤Ns≤(N1+N2).

5. The resonator with a common reflector according to claim 1, characterized in that When the second direction length of the reflector of the first IDT electrode portion before forming the common reflector is called H1, and the second direction length of the reflector of the second IDT electrode portion is called H2, the second direction length HS of the common reflector satisfies the condition Max(H1, H2)≤HS.

6. The resonator with a common reflector according to claim 1, characterized in that When the distance between the IDT electrodes in the first IDT electrode portion is referred to as T1 and the distance between the IDT electrodes in the second IDT electrode portion is referred to as T2, the distance TS1 between the reflector electrodes of the common reflector satisfies the condition of Max(T1, T2)≤TS1.

7. A resonator having a common reflector, characterized in that include: First to nth IDT electrode portions (n ​​is a natural number greater than or equal to 3), which are formed on the piezoelectric substrate and are arranged in parallel along a first direction; first to n-1th common reflectors, which are respectively formed between the first to nth IDT electrode portions and shared between two adjacent IDT electrode portions among the first to nth IDT electrode portions; as well as The first reflector and the n-th reflector are formed on the opposite sides of the common reflector in a manner parallel to the first IDT electrode portion and the n-th IDT electrode portion.

8. The resonator with a common reflector according to claim 7, characterized in that The first to nth IDT electrode portions include: A first bus bar and a second bus bar extending along a first direction and spaced apart from each other along a second direction perpendicular to the first direction; The first IDT electrodes and the second IDT electrodes are alternately extended from the first bus bar and the second bus bar along the second direction and are spaced apart from each other along the first direction.

9. The resonator with a common reflector according to claim 7, characterized in that Reflectors include: a pair of reflector busbars extending along a first direction and spaced apart from each other along a second direction perpendicular to the first direction; A plurality of reflector electrodes are elongated along the second direction and are spaced apart from each other along the first direction.

10. The resonator with a common reflector according to claim 7, characterized in that When the number of reflector electrodes of the n-1th electrode portion before forming the n-1th common reflector is called Nn-1, and the number of reflector electrodes of the nIDT electrode portion is called Nn, the number Ns of reflector electrodes of the n-1th common reflector satisfies the condition Min(Nn-1, Nn)≤Ns≤(Nn-1+Nn).

11. The resonator with a common reflector according to claim 7, characterized in that When the second direction length of the reflector of the n-1th IDT electrode portion before forming the n-1th common reflector is called Hn-1, and the second direction length of the reflector of the n-1th IDT electrode portion is called Hn, then the second direction length HSn-1 of the n-1th common reflector satisfies the condition Max(Hn-1, Hn)≤HSn-1.

12. The resonator with a common reflector according to claim 7, characterized in that When the distance between IDT electrodes of the n-1th IDT electrode portion is called Tn-1, and the distance between IDT electrodes of the nth IDT electrode portion is called Tn, then the distance TSn-1 between reflector electrodes of the common reflector satisfies the condition Max(Tn-1, Tn)≤TSn-1.

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