Surface acoustic wave resonators and surface acoustic wave filters

Abstract

The present application relates to a surface acoustic wave resonator and a surface acoustic wave filter, including an interdigital transducer, the interdigital transducer comprising: a first bus bar and first electrode fingers and first dummy electrode fingers alternately connected to the first bus bar; a second bus bar and second electrode fingers and second dummy electrode fingers alternately connected to the second bus bar; a first gap between the first electrode finger and the second dummy electrode finger; a second gap between the second electrode finger and the first dummy electrode finger; each first gap is arranged along a first direction, each second gap is arranged along a second direction, and the angle between the first direction and the third direction is different from the angle between the second direction and the third direction. By setting the angle between the first direction and the third direction to be different from the angle between the second direction and the third direction, the present application can block transverse energy leakage in surface acoustic waves, suppress transverse mode ripples in surface acoustic waves, and improve electrical performance.

Description

Technical Field

[0001] The present application relates to the field of communications, and in particular to a surface acoustic wave resonator and a surface acoustic wave filter. Background Art

[0002] With the advancement of communication technology, product terminals have placed stringent performance requirements on various components. Filters are key components in communication systems. With this technological advancement, filter types are also increasing, from LCR filters to cavity filters, from LTCC ceramic filters to surface acoustic wave filters. Filter technology continues to advance. Since the advent of the LTE era, the role of surface acoustic wave filters in communication systems has become increasingly important. Simultaneously, with the advancement of communication technology, the requirements for filters are also becoming increasingly stringent. In particular, with the advent of fifth-generation mobile communication technology (5G), the filter industry faces significant challenges and opportunities.

[0003] Surface acoustic wave (SAW) devices based on single-crystal piezoelectric lithium tantalate (LTTA) substrates have been widely used in RF filters. However, due to the limitations of the Q value and high-frequency temperature coefficient of single-crystal piezoelectric materials, they no longer meet the requirements of RF front-end chips. SAW resonators and RF filters that still use traditional designs exhibit strong transverse mode ripples and severe passband noise in practical applications, leading to degraded overall device performance. Summary of the Invention

[0004] Based on this, it is necessary to provide a surface acoustic wave resonator and a surface acoustic wave filter that suppress the transverse mode ripples in the surface acoustic wave and improve the electrical performance.

[0005] A surface acoustic wave resonator, comprising:

[0006] substrate layer;

[0007] an electrode layer, the electrode layer being located on the substrate layer; the electrode layer comprising an interdigital transducer;

[0008] The interdigital transducer comprises: a first bus bar and first electrode fingers and first dummy electrode fingers alternately connected to the first bus bar; a second bus bar and second electrode fingers and second dummy electrode fingers alternately connected to the second bus bar; the first electrode fingers and the second dummy electrode fingers are arranged opposite to each other, with a first gap between the first electrode fingers and the second dummy electrode fingers; the second electrode fingers and the first dummy electrode fingers are arranged opposite to each other, with a second gap between the second electrode fingers and the first dummy electrode fingers;

[0009] In which, each of the first gaps is arranged along a first direction, each of the second gaps is arranged along a second direction, the angle between the first direction and the third direction is different from the angle between the second direction and the third direction; in a direction parallel to the plane of the substrate layer, the third direction is perpendicular to the length direction of the first electrode finger.

[0010] In one embodiment, the third direction and the length direction of the first electrode finger are divided into a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant; the first quadrant is centrally symmetrical with the second quadrant, and the third quadrant is centrally symmetrical with the fourth quadrant;

[0011] The first direction and the second direction are both located in the first quadrant, the second quadrant, the third quadrant or the fourth quadrant;

[0012] Or, the first direction is located in one of the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, and the second direction is located in another quadrant except the quadrant where the first direction is located;

[0013] Alternatively, one of the first direction and the second direction is parallel to the third direction, and the other of the first direction and the second direction has an included angle.

[0014] In one embodiment, the first electrode finger and the first dummy electrode finger are arranged obliquely or perpendicularly to the first bus bar;

[0015] And / or, the second electrode fingers and the second dummy electrode fingers are arranged obliquely or perpendicularly to the second bus bar.

[0016] In one embodiment, the first bus bar, the first electrode finger, the first dummy electrode finger, the second bus bar, the second electrode finger and the second dummy electrode finger together form a connecting piece, and the connecting piece includes multiple pieces, and the multiple connecting pieces are connected in sequence and distributed according to a set shape.

[0017] In one embodiment, the angle between the first direction and the third direction, and the angle between the second direction and the third direction on each of the connecting pieces are different.

[0018] In one embodiment, the connecting pieces include two, the first bus bars on the two connecting pieces are connected to each other, and the second bus bars on the two connecting pieces are connected to each other; and the set shape is a broken line shape.

[0019] In one embodiment, the set shape includes a straight line distribution, a broken line or a polygon.

[0020] In one embodiment, the angle between the first direction and the third direction is α, the angle between the second direction and the third direction is β, and the difference between the absolute values of α and β ranges from 0.2° to 3°.

[0021] In one embodiment, a first thickened portion is provided at one end of the first electrode finger close to the second dummy electrode finger, and a second thickened portion is provided at one end of the second electrode finger close to the first dummy electrode finger; a third thickened portion is provided at one end of the first dummy electrode finger close to the second electrode, and a fourth thickened portion is provided at one end of the second dummy electrode finger close to the first electrode finger.

[0022] The present application also provides a surface acoustic wave filter, comprising the above-mentioned surface acoustic wave resonator.

[0023] In the above solution, by setting the angle between the first direction and the third direction to be different from the angle between the second direction and the third direction, the lateral energy leakage in the surface acoustic wave can be blocked, the lateral mode ripples in the surface acoustic wave can be suppressed, and the electrical performance can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 FIG. 4 is a schematic structural diagram of a surface acoustic wave resonator according to an embodiment of the present invention.

[0025] Figure 2 FIG. 4 is a schematic structural diagram of an interdigital transducer according to another embodiment of the present invention.

[0026] Figure 3 Schematic diagram of the structure of an interdigital transducer according to another embodiment of the present invention.

[0027] Figure 4 Schematic diagram of the structure of an interdigital transducer according to another embodiment of the present invention.

[0028] Figure 5 Schematic diagram of the structure of an interdigital transducer according to another embodiment of the present invention.

[0029] Figure 6 Schematic diagram of the structure of an interdigital transducer according to another embodiment of the present invention.

[0030] Figure 7 Schematic diagram of the structure of an interdigital transducer according to another embodiment of the present invention.

[0031] Figure 8 Schematic diagram of the structure of an interdigital transducer according to another embodiment of the present invention.

[0032] Description of Reference Numerals

[0033] 10. Surface acoustic wave resonator; 100. Electrode layer; 110. Interdigital transducer; 111. First bus bar; 112. First electrode finger; 113. First dummy electrode finger; 114. Second bus bar; 115. Second electrode finger; 116. Second dummy electrode finger; 117. First gap; 118. Second gap; 120. Connector; 130. Reflector structure; 131. Third bus bar; 132. Fourth bus bar; 133. Reflector;

[0034] a. First direction; b. Second direction; c. Third direction. DETAILED DESCRIPTION

[0035] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0036] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0037] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0038] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0039] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0040] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0041] See Figure 1 、 Figure 2 and Figure 3 One embodiment of the present invention provides a surface acoustic wave resonator 10, comprising a substrate layer and an electrode layer 100, wherein the electrode layer 100 is located on the substrate layer. Specifically, the surface acoustic wave resonator 10 also includes a piezoelectric layer, which is located on the substrate layer, and the electrode layer 100 is located on a side of the piezoelectric layer away from the substrate layer.

[0042] Exemplarily, the material of the substrate layer can be high-resistance silicon, which can be P-type high-resistance silicon or N-type high-resistance silicon, with a resistivity greater than 2000Ω·cm. Preferably, the resistivity of the high-resistance silicon is greater than 10000Ω·cm. The material of the piezoelectric layer can be lithium tantalate or lithium niobate, wherein the lithium tantalate cut angle can be 30° to 50°, and the thickness of the piezoelectric layer can be in the range of 300 to 1000nm. A metal film is deposited on the surface of the piezoelectric layer by electron beam evaporation, plasma, magnetron sputtering, etc. to form the electrode layer 100, wherein the material of the deposited metal film can be titanium, chromium, copper, silver, aluminum, etc., or a combination thereof.

[0043] See Figure 1 、 Figure 2 and Figure 3 The electrode layer 100 includes an interdigital transducer 110. The interdigital transducer 110 includes: a first bus bar 111, and first electrode fingers 112 and first dummy electrode fingers 113 alternately connected to the first bus bar 111; a second bus bar 114, and second electrode fingers 115 and second dummy electrode fingers 116 alternately connected to the second bus bar 114. The first electrode fingers 112 and the second dummy electrode fingers 116 are arranged opposite each other, with a first gap 117 between them. The second electrode fingers 115 and the first dummy electrode fingers 113 are arranged opposite each other, with a second gap 118 between them.

[0044] The first gaps 117 are arranged along a first direction a, and the second gaps 118 are arranged along a second direction b. The angle between the first direction a and the third direction c is different from the angle between the second direction b and the third direction c. In a direction parallel to the plane of the substrate layer, the third direction c is perpendicular to the length direction of the first electrode fingers 112. By setting the angle between the first direction a and the third direction c to be different from the angle between the second direction b and the third direction c, transverse energy leakage in surface acoustic waves can be blocked, transverse mode ripples in the surface acoustic waves can be suppressed, and electrical performance can be improved.

[0045] Specifically, the numbers of the first electrode fingers 112, the second electrode fingers 115, the first dummy electrode fingers 113 and the second electrode fingers 115 are all arranged in a one-to-one correspondence. That is, the numbers of the first electrode fingers 112, the second electrode fingers 115, the first dummy electrode fingers 113 and the second electrode fingers 115 are all the same.

[0046] See also Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 and Figure 6According to some embodiments of the present application, the third direction c and the lengthwise direction of the first electrode fingers 112 can optionally be separated into a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant. The first quadrant is centrally symmetrical with the second quadrant, and the third quadrant is centrally symmetrical with the fourth quadrant. Specifically, the intersection of the third direction c and the lengthwise direction of the first electrode fingers 112 serves as the center of the quadrant. The third direction c serves as the x-axis of the quadrant, and the lengthwise direction of the first electrode fingers 112 serves as the y-axis of the quadrant.

[0047] In one embodiment, the first direction a and the second direction b are both located in the first quadrant, the second quadrant, the third quadrant, or the fourth quadrant. Figure 1 and Figure 5 As shown, the first direction a and the second direction b are both located in the first quadrant. Based on the quadrant, the angles between the first direction a and the second direction b and the third direction c range from 0° to 90°. Figure 3 As shown, the first direction a and the second direction b are both located in the second quadrant. Based on the quadrant, the angles between the first direction a and the second direction b and the third direction c range from 90° to 180°. In a third embodiment, the first direction a and the second direction b are both located in the third quadrant. Based on the quadrant, the angles between the first direction a and the second direction b and the third direction c range from 180° to 270°. In a fourth embodiment, the first direction a and the second direction b are both located in the fourth quadrant. Based on the quadrant, the angles between the first direction a and the second direction b and the third direction c range from 270° to 360°.

[0048] In another embodiment, the first direction a is located in one of the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, and the second direction b is located in another quadrant except the quadrant where the first direction a is located.

[0049] Specifically, in the fifth embodiment, the first direction a is located in the first quadrant, and the second direction b is located in the second quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 0° to 90°. The angle between the second direction b and the third direction c ranges from 90° to 180°.

[0050] In the sixth embodiment, the first direction a is located in the first quadrant, and the second direction b is located in the third quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 0° to 90°. The angle between the second direction b and the third direction c ranges from 180° to 270°.

[0051] In the seventh embodiment, the first direction a is located in the first quadrant, and the second direction b is located in the fourth quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 0° to 90°. The angle between the second direction b and the third direction c ranges from 270° to 360°.

[0052] In the eighth embodiment, the first direction a is located in the second quadrant, and the second direction b is located in the third quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 90° to 180°. The angle between the second direction b and the third direction c ranges from 180° to 270°.

[0053] In the ninth embodiment, the first direction a is located in the second quadrant, and the second direction b is located in the fourth quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 90° to 180°. The angle between the second direction b and the third direction c ranges from 270° to 360°.

[0054] In the tenth embodiment, the first direction a is located in the third quadrant, and the second direction b is located in the fourth quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 180° to 270°. The angle between the second direction b and the third direction c ranges from 270° to 360°.

[0055] In the eleventh embodiment, see Figure 2 As shown, the first direction a is located in the fourth quadrant, and the second direction b is located in the first quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 270° to 360°. The angle between the second direction b and the third direction c ranges from 0° to 90°.

[0056] In the twelfth embodiment, see Figure 4 As shown, the first direction a is located in the third quadrant, and the second direction b is located in the second quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 180° to 270°. The angle between the second direction b and the third direction c ranges from 90° to 180°.

[0057] In the thirteenth embodiment, see Figure 6 As shown, the first direction a is located in the second quadrant, and the second direction b is located in the first quadrant. Based on the quadrant, the angle between the first direction a and the third direction c ranges from 90° to 180°. The angle between the second direction b and the third direction c ranges from 0° to 90°.

[0058] In another embodiment, one of the first direction a and the second direction b is parallel to the third direction c, and the other of the first direction a and the second direction b has an angle. In this embodiment, the angle between one of the first direction a and the second direction b and the third direction c is 0°.

[0059] See also Figures 1 to 6 According to some embodiments of the present application, optionally, the first electrode fingers 112 and the first dummy electrode fingers 113 are arranged obliquely or perpendicularly to the first bus bar 111 , and the second electrode fingers 115 and the second dummy electrode fingers 116 are arranged obliquely or perpendicularly to the second bus bar 114 .

[0060] Specifically, in the first embodiment, see Figure 5 and Figure 6 As shown, the first electrode fingers 112 and the first dummy electrode fingers 113 are arranged perpendicular to the first bus bar 111. The second electrode fingers 115 and the second dummy electrode fingers 116 are arranged perpendicular to the second bus bar 114. In this embodiment, the extension direction of the first bus bar 111 and the second bus bar 114 is parallel to the third direction c.

[0061] In another embodiment, see Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, the first electrode fingers 112 and the first dummy electrode fingers 113 are arranged at an angle relative to the first bus bar 111. The second electrode fingers 115 and the second dummy electrode fingers 116 are arranged at an angle relative to the second bus bar 114. It should be understood that the tilt angles between the first electrode fingers 112 and the first dummy electrode fingers 113 and the first bus bar 111, and the tilt angles between the second electrode fingers 115 and the second dummy electrode fingers 116 and the second bus bar 114 are not limited in this application and can be set according to usage requirements.

[0062] For example, the inclination angle between the first electrode finger 112 and the first dummy electrode finger 113 and the first bus bar 111, and the inclination angle between the second electrode finger 115 and the second dummy electrode finger 116 and the second bus bar 114 can be the angle between the first direction a and the third direction c, or the angle between the second direction b and the third direction c, which is not limited in this application.

[0063] See also Figure 1 、 Figure 2 、 Figure 7 and Figure 8 According to some embodiments of the present application, first bus bar 111, first electrode finger 112, first dummy electrode finger 113, second bus bar 114, second electrode finger 115, and second dummy electrode finger 116 may collectively form a connecting piece 120. Connecting pieces 120 may include a plurality of connecting pieces 120, which are sequentially connected and distributed in a predetermined shape. This application does not limit the number of connecting pieces 120, and the number may be set based on actual needs.

[0064] Specifically, see Figure 7As shown, the angles between the first direction a and the third direction c, and the angles between the second direction b and the third direction c, are different on each connecting piece 120. By setting the angles between the first direction a and the third direction c, and the angles between the second direction b and the third direction c, on each connecting piece 120 to be different, transverse energy leakage in surface acoustic waves can be further prevented, transverse mode ripples in surface acoustic waves can be suppressed, and electrical performance can be improved.

[0065] In one embodiment, see Figure 8 As shown, the connecting piece 120 includes two, the first bus bars 111 on the two connecting pieces 120 are connected to each other, and the second bus bars 114 on the two connecting pieces 120 are connected to each other, and the shape is set to be a broken line. Specifically, there is an angle between the first bus bars 111 on the two connecting pieces 120.

[0066] In another embodiment, the predetermined shape includes a straight line distribution, a broken line distribution, or a polygonal distribution. For example, the predetermined shape can be an equilateral triangle distribution or a right triangle distribution, or can also be a rhombus, a square, a rectangle, or a trapezoid. The number of connecting pieces 120 can also be five, six, or even more.

[0067] See also Figure 1 、 Figure 2 、 Figure 3 and Figure 4 According to some embodiments of the present application, optionally, the angle between the first direction a and the third direction c is α, the angle between the second direction b and the third direction c is β, and the absolute value of the difference between α and β ranges from 0.2° to 3°.

[0068] Specifically, the range of the angle α between the first direction a and the third direction c is: 0°~12°. The range of the angle β between the second direction b and the third direction c is: 0°~12°. It should be noted that this application does not limit the angle α between the first direction a and the third direction c and the angle β between the second direction b and the third direction c. The angle α between the first direction a and the third direction c can be selected between 0°~12°. The angle β between the second direction b and the third direction c can be selected between 0°~12°. It should be noted that: if the angle α between a direction and the third direction c is 0°, the angle β between the second direction b and the third direction c is not 0.

[0069] The angle α between the first direction a and the third direction c may be greater than the angle β between the second direction b and the third direction c. Alternatively, the angle α between the first direction a and the third direction c may be less than the angle β between the second direction b and the third direction c. This is not limited in this application as long as the absolute value of the difference between α and β is within the range of 0.2° to 3°. For example, the angle α between the first direction a and the third direction c is 8°. The angle β between the second direction b and the third direction c is 6°.

[0070] See also Figure 1 and Figure 2 According to some embodiments of the present application, a first thickened portion is optionally provided at an end of the first electrode finger 112 close to the second dummy electrode finger 116. A second thickened portion is provided at an end of the second electrode finger 115 close to the first dummy electrode finger 113. A third thickened portion is provided at an end of the first dummy electrode finger 113 close to the second electrode. A fourth thickened portion is provided at an end of the second dummy electrode finger 116 close to the first electrode finger 112.

[0071] The first, second, third, and fourth thickened portions have the same dimensions. In the third direction c, the width of the first thickened portion is greater than the width of the first electrode finger 112. The width of the second thickened portion is greater than the width of the second electrode finger 115. The width of the third thickened portion is greater than the width of the first dummy electrode finger 113. The width of the fourth thickened portion is greater than the width of the second dummy electrode finger 116.

[0072] By providing the first, second, third, and fourth thickened portions, the first, second, third, and fourth thickened portions can block lateral energy leakage in surface acoustic waves, suppress clutter in the surface acoustic waves, and improve the Q value of the surface acoustic wave resonator 10. For example, the first, second, third, and fourth thickened portions are rectangular in shape. The first, second, third, and fourth thickened portions can also be triangular, polygonal, or groove-shaped.

[0073] Specifically, the first thickened portion is arranged opposite to the fourth thickened portion, and the second thickened portion is arranged opposite to the third thickened portion, which can further block the lateral energy leakage in the surface acoustic wave, suppress the clutter in the surface acoustic wave, and further improve the Q value of the surface acoustic wave resonator 10.

[0074] See also Figure 1 、 Figure 2 and Figure 8According to some embodiments of the present application, the electrode layer 100 optionally further includes a reflective grating structure 130, which includes a third bus bar 131, a fourth bus bar 132, and a reflective grating 133. The third bus bar 131 and the fourth bus bar 132 are arranged in parallel. The first end of the reflective grating 133 is connected to the third bus bar 131, and the second end of the reflective grating 133 is connected to the fourth bus bar 132. Specifically, the third bus bar 131 and the fourth bus bar 132 are arranged perpendicular to the reflective grating 133.

[0075] A reflection grating structure 130 is provided on opposite sides of the IDT 110. The reflection grating structure 130 can reflect the energy of the surface acoustic wave and concentrate the energy in the IDT 110. Specifically, the reflection grating 133 is arranged parallel to the first electrode finger 112, the first dummy electrode finger 113, the second electrode finger 115, and the second dummy electrode finger 116, further ensuring that the reflection grating structure 130 concentrates the reflected surface acoustic wave energy into the IDT 110, further improving the Q value of the SAW resonator 10.

[0076] The present application also provides a surface acoustic wave filter, including the above-mentioned surface acoustic wave resonator 10. Specifically, the surface acoustic wave filter provided in the embodiment of the present application has corresponding beneficial effects as the surface acoustic wave resonator 10 provided in any embodiment of the present application. The technical details not detailed in this embodiment are detailed in the surface acoustic wave resonator 10 provided in any embodiment of the present application.

[0077] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A surface acoustic wave resonator, characterized in that: include: substrate layer; an electrode layer, wherein the electrode layer is located on the substrate layer; The electrode layer includes an interdigital transducer; The interdigital transducer comprises: a first bus bar and first electrode fingers and first dummy electrode fingers alternately connected to the first bus bar; a second bus bar and second electrode fingers and second dummy electrode fingers alternately connected to the second bus bar; the first electrode fingers and the second dummy electrode fingers are arranged opposite to each other, with a first gap between the first electrode fingers and the second dummy electrode fingers; the second electrode fingers and the first dummy electrode fingers are arranged opposite to each other, with a second gap between the second electrode fingers and the first dummy electrode fingers; In which, each of the first gaps is arranged along a first direction, each of the second gaps is arranged along a second direction, the angle between the first direction and the third direction is different from the angle between the second direction and the third direction; the angle between the first direction and the third direction is α, the angle between the second direction and the third direction is β, and the difference between the absolute values of α and β ranges from 0.2° to 3°; in a direction parallel to the plane of the substrate layer, the third direction is perpendicular to the length direction of the first electrode finger.

2. The surface acoustic wave resonator according to claim 1, wherein The third direction and the length direction of the first electrode finger are separated to form a first quadrant, a second quadrant, a third quadrant and a fourth quadrant; the first quadrant is centrally symmetrical to the second quadrant, and the third quadrant is centrally symmetrical to the fourth quadrant; The first direction and the second direction are both located in the first quadrant, the second quadrant, the third quadrant or the fourth quadrant; Or, the first direction is located in one of the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, and the second direction is located in another quadrant except the quadrant where the first direction is located; Alternatively, one of the first direction and the second direction is parallel to the third direction, and the other of the first direction and the second direction has an included angle.

3. The surface acoustic wave resonator according to claim 1, wherein The first electrode fingers and the first dummy electrode fingers are arranged obliquely or perpendicularly to the first bus bar; And / or, the second electrode fingers and the second dummy electrode fingers are arranged obliquely or perpendicularly to the second bus bar.

4. The surface acoustic wave resonator according to claim 1, wherein The first bus bar, the first electrode finger, the first dummy electrode finger, the second bus bar, the second electrode finger and the second dummy electrode finger together form a connecting piece. The connecting piece includes a plurality of connecting pieces, and the plurality of connecting pieces are connected in sequence and distributed in a set shape.

5. The surface acoustic wave resonator according to claim 4, characterized in that An angle between the first direction and the third direction, and an angle between the second direction and the third direction on each of the connecting pieces are different.

6. The surface acoustic wave resonator according to claim 4, characterized in that The connecting pieces include two, the first bus bars on the two connecting pieces are connected to each other, and the second bus bars on the two connecting pieces are connected to each other; the set shape is a broken line shape.

7. The surface acoustic wave resonator according to claim 4, characterized in that The set shape includes a straight line distribution, a broken line shape or a polygonal shape.

8. The surface acoustic wave resonator according to claim 1, wherein A first thickening portion is provided at one end of the first electrode finger close to the second dummy electrode finger, and a second thickening portion is provided at one end of the second electrode finger close to the first dummy electrode finger; a third thickening portion is provided at one end of the first dummy electrode finger close to the second electrode, and a fourth thickening portion is provided at one end of the second dummy electrode finger close to the first electrode finger.

9. A surface acoustic wave filter, characterized in that: The surface acoustic wave resonator comprises the surface acoustic wave resonator according to any one of claims 1 to 8.

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