Filter, manufacturing method thereof and wireless communication device

Abstract

The invention provides a filter, a manufacturing method thereof and a wireless communication device. The filter comprises a resonator unit, a signal leading-out coupling unit and a grounding electrode. The resonator unit includes a plurality of resonators arranged in a first direction. Each resonator is provided with a signal end and a grounding end which are located on the two sides of the resonator in the second direction respectively, and the second direction intersects with the first direction. The signal lead-out coupling unit is located at the side where the plurality of signal ends in the resonator unit are located, and is electrically connected with the signal ends. The grounding electrode is located on the side where the grounding end in the resonator unit is located and is electrically connected with the grounding ends of all the resonators. According to the filter, by adjusting the structures and position distribution of the signal leading-out coupling unit and the grounding electrode, on the premise that the working performance of the filter is guaranteed, the chip area is effectively reduced, and the miniaturization reference requirement of the filter is met. The manufacturing method is simple in steps. The wireless communication device is suitable for miniaturized high-performance application scenarios.

Description

Technical Field

[0001] The present invention relates to the field of integrated circuits and communication technology, and in particular to a filter and a manufacturing method thereof, and a wireless communication device. Background Art

[0002] Surface acoustic wave (SAW) technology has been widely used in communication equipment since the 1960s. Traditional SAW filters usually rely on a single acoustic wave mode. Although they perform well in frequency selectivity and insertion loss, their limitations in bandwidth, selectivity, and miniaturization are becoming increasingly apparent. With the rapid development of wireless communications, especially the promotion of 4G and 5G technologies, the performance requirements for filters are constantly increasing, which has created market conditions for the emergence of dual-mode coupled surface acoustic wave (DMS) filters.

[0003] The DMS filter uses the characteristics of surface acoustic waves propagating on the surface of the substrate to achieve coupling of different modes of sound waves through precisely designed electrodes and material structures. The basic principle is to achieve the desired frequency response by adjusting the interaction between different sound wave modes. This coupling method gives the DMS filter greater flexibility and superiority in terms of frequency selectivity, bandwidth, and power consumption. Based on this, the application prospects of the DMS filter are broad, especially in 5G communications, the Internet of Things, and high-frequency wireless communications. Its high selectivity and broadband characteristics make it an indispensable component in modern communication systems. In the future, with the continuous advancement of technology, DMS filters are expected to show greater potential in more emerging fields such as smart sensing, medical equipment, and autonomous driving.

[0004] Due to the Internet of Things' technical requirements for miniaturization and integration of terminal chips, filters need to minimize chip size while ensuring low insertion loss, high rectangularity and large bandwidth. However, the current methods for improving the miniaturization of filter chips either introduce additional losses or mismatching problems, affecting the filter's working performance such as insertion loss and return loss, or the manufacturing process is difficult, which is not conducive to large-scale production.

[0005] Therefore, how to provide a filter and a manufacturing method thereof, and a wireless communication device to achieve miniaturization of the filter chip while ensuring the working performance of the filter has become an important technical problem that needs to be urgently solved by those skilled in the art.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0007] Based on this, it is necessary to provide a filter and a method for manufacturing the filter and a wireless communication device to address the problem that the methods used in the prior art to improve the miniaturization of filter chips may affect the working performance of the filter or increase the difficulty of the process.

[0008] To achieve the above objectives and other related objectives, in a first aspect, a filter is provided, comprising:

[0009] A resonator unit, comprising a plurality of resonators, wherein the plurality of resonators are arranged in a first direction, each of the resonators has a signal end and a ground end, the signal end and the ground end are respectively located at two sides of the resonator in a second direction, and the second direction intersects with the first direction;

[0010] A signal extraction coupling unit is located at a side where the plurality of signal terminals in the resonator unit are located, and the signal extraction coupling unit is electrically connected to the plurality of signal terminals in the resonator unit;

[0011] A grounding electrode is located at a side where the multiple grounding ends in the resonator unit are located, and the grounding electrode is electrically connected to the grounding ends of all the resonators.

[0012] In one embodiment, the signal lead-out coupling unit includes a first signal electrode and a second signal electrode which are separately arranged, and the signal lead-out coupling unit is connected to a plurality of the signal ends in the resonator unit, including: the first signal electrode is electrically connected to a part of the signal ends in the resonator unit, and the second signal electrode is electrically connected to another part of the signal ends in the resonator unit.

[0013] In one embodiment, the resonator unit includes at least one first resonator and at least one second resonator, the first resonator has a first signal end, the second resonator has a second signal end, the first signal electrode is electrically connected to the first signal end, and the second signal electrode is electrically connected to the second signal end, wherein the first signal electrode is used for one of inputting a signal and outputting a signal, and the second signal electrode is used for the other of inputting a signal and outputting a signal.

[0014] In one embodiment, the first signal electrode spans over the first signal end and the second signal end, and the first signal electrode is electrically isolated from the second signal end.

[0015] In one embodiment, the filter further includes an isolation structure and an electrical connection structure, the isolation structure is located between the first signal electrode and the second signal end, and the electrical connection structure is located between the first signal electrode and the first signal end.

[0016] In one embodiment, the second signal end includes an overlapping portion and a non-overlapping portion, the overlapping portion is located below the first signal electrode, the isolation structure at least covers the overlapping portion to isolate the overlapping portion from the first signal electrode, and in the first direction, the width of the overlapping portion is smaller than the width of the non-overlapping portion.

[0017] In one embodiment, the filter comprises:

[0018] A first metal layer is sequentially divided into a first region, a second region, and a third region along the second direction, wherein a portion of the first metal layer located in the first region includes the ground electrode, a portion of the first metal layer located in the second region includes the resonator unit, and a portion of the first metal layer located in the third region includes the second signal electrode;

[0019] A second metal layer, located above the first metal layer, the second metal layer comprising the electrical connection structure connected to the second signal terminal;

[0020] An isolation layer, distributed in the same layer as the second metal layer, the isolation layer comprising the isolation structure covering a portion of the first signal terminal;

[0021] The third metal layer is located above the isolation layer and the second metal layer, and the third metal layer includes the second signal electrode connected to the electrical connection structure.

[0022] In one embodiment, the filter also includes at least one of a first coupling capacitor, a second coupling capacitor and a third coupling capacitor, the first coupling capacitor is based on the first signal end and the second signal end, the second coupling capacitor is based on the second signal end, the isolation structure and the first signal electrode, and the third coupling capacitor is based on the first signal end and the second signal electrode.

[0023] In one embodiment, the resonator unit includes a plurality of the first resonators and a plurality of the second resonators, and the plurality of the first resonators and the plurality of the second resonators are arranged alternately.

[0024] In a second aspect, a method for manufacturing a filter is provided, for manufacturing the filter according to the first aspect, the manufacturing method comprising the following steps:

[0025] forming a resonator unit, the resonator unit comprising a plurality of resonators, the plurality of resonators being arranged in a first direction, each of the resonators having a signal end and a ground end, the signal end and the ground end being opposite to each other in a second direction, the second direction intersecting with the first direction;

[0026] A signal coupling unit is formed on the side where the plurality of signal ends in the resonator unit are located, and the signal extraction coupling unit is electrically connected to the plurality of signal ends in the resonator unit;

[0027] A grounding electrode is formed on the side where the multiple grounding ends in the resonator unit are located, and the grounding electrode is electrically connected to the grounding ends of all the resonators.

[0028] According to a third aspect, a wireless communication device is provided, wherein the wireless communication device comprises the filter as described in the first aspect.

[0029] As described above, the filter of the present invention, by adjusting the structure and position distribution of the signal extraction coupling unit and the ground electrode, effectively reduces the area of ​​the filter chip while ensuring the working performance of the filter, and meets the miniaturization reference requirements of the filter. In addition, based on the parameter control of the local structure (signal extraction coupling unit, signal terminal and isolation layer) in the filter, the rectangular degree of the right side of the filter can be adjusted without connecting capacitors in parallel outside the filter structure, simplifying the circuit structure of the filter. In addition, through the structural design of the second signal terminal, the probability of short circuit in the filter can also be reduced, and the reliability of the device can be improved. The manufacturing method of the filter of the present invention has simple manufacturing steps and is easy to realize large-scale production. The wireless communication device of the present invention has a small overall area, and has high reliability and working performance, and is suitable for miniaturized high-performance application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Shown is a schematic diagram of the layout structure of a filter provided by the present invention.

[0031] Figure 2 Display as Figure 1 Schematic diagram of the filter structure shown.

[0032] Figure 3 Shown is a schematic structural diagram of a first resonator and a second resonator in a filter provided by the present invention.

[0033] Figure 4 Display as Figure 2 Schematic diagram of the cross section of the A-A' portion.

[0034] Figure 5 Display as Figure 2 Schematic diagram of the cross section of the B-B' portion.

[0035] Figure 6 Shown is a schematic diagram of the split structure of the first metal layer in a filter provided by the present invention.

[0036] Figure 7 Display as Figure 2 Schematic diagram of area I from above.

[0037] Figure 8 Shown is a comparison diagram of S(2,1) transmission coefficient curves of two filter structures provided by the present invention.

[0038] Fig. 9 A schematic diagram of the layout structure of a filter provided as a comparative example is shown.

[0039] Fig.10 Display as Fig. 9 The structural diagram of the filter is shown.

[0040] Fig.11 Display as Fig. 9 Schematic diagram of the arrangement of two adjacent resonators in the filter shown.

[0041] Fig.12 It shows a comparison of the S(2,1) transmission coefficient curves of the filters of Example 1 and the comparative example.

[0042] Fig.13 Display as Fig.10 A top-down diagram of the middle II area.

[0043] Fig.14 Shown is a topological structure diagram of a duplexer provided in Example 3.

[0044] Description of reference numerals:

[0045] 10-resonator unit, 11-resonator, 111-signal end, 112-ground end, 113-interdigitated electrode, 114-bus bar, 11a-first resonator, 111a-first signal end, 11b-second resonator, 111b-second signal end, 1111-overlapping portion, 1112-non-overlapping portion, 20-first signal electrode, 30-second signal electrode, 40-ground electrode, 40a-first ground electrode, 40b-second ground electrode, 50-isolation structure, 60-electrical connection structure; 71-first coupling capacitor, 72-second coupling capacitor, 73-third coupling capacitor; 80-reflection grid;

[0046] 20-signal extraction coupling unit, 21-first signal electrode, 22-second signal electrode, 20a-output electrode, 20b-input electrode, 30-ground electrode, 30a-first ground electrode, 30b-second ground electrode, 40-isolation structure, 50-electrical connection structure; 61-first coupling capacitor, 62-second coupling capacitor, 63-third coupling capacitor, 70-reflection grid;

[0047] 100 - first metal layer, 101 - first region, 102 - second region, 103 - third region, 201 - second metal layer, 202 - isolation layer, 300 - third metal layer; 400 - piezoelectric material layer;

[0048] 600- duplexer, 601- transmitting unit, 602- receiving unit, 603- antenna, 604- filter, 605- parallel resonator, 606- series resonator. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0050] In the description of the present invention, it should be understood that 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" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0051] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0054] It should be noted that when 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 a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0055] Embodiment 1

[0056] This embodiment provides a filter. Figure 1 , Figure 1 The schematic diagram of the layout structure of the filter provided in this embodiment is shown. The filter includes a resonator unit 10, a signal extraction coupling unit 20 and a ground electrode 30.

[0057] Specifically, see Figure 2 , Figure 2 It shows a Figure 1The structural schematic diagram of the filter shown in the figure. The resonator unit 10 includes a plurality of resonators 11. The plurality of resonators 11 are arranged in a first direction X (that is, the arrangement direction of the plurality of resonators 11 in the first filter). Each of the resonators 11 has a signal terminal 111 and a ground terminal 112, and the signal terminal 111 and the ground terminal 112 are respectively located on both sides of the resonator 11 in a second direction Y. The second direction Y intersects with the first direction X (for example, intersects perpendicularly). The signal extraction coupling unit 201 is located on the side where the plurality of signal terminals 111 in the resonator unit 10 are located. The signal extraction coupling unit 20 is electrically connected to the plurality of signal terminals 111 in the resonator unit 10. For example, each of the resonators 11 includes two bus bars 114 and a plurality of interdigitated electrodes 113, wherein the plurality of interdigitated electrodes 113 are arranged between the two bus bars 114 and are alternately connected to the two bus bars 114, wherein one bus bar 114 of the resonator 11 is connected to the signal terminal 111, and another bus bar 114 of the resonator is connected to the ground terminal 112 (please refer to 3).

[0058] like Figure 2 As shown, the ground electrode 30 is located on the side where the multiple ground terminals 112 in the resonator unit 10 are located, and the ground electrode 30 is electrically connected to the ground terminals 112 of all the resonators 11. For example, the filter is a DMS filter. The resonator unit 10 constitutes a resonance region, and the surface acoustic wave is mainly excited and propagated in the resonance region. The signal extraction coupling unit 20 is located on one side of the resonance region, and the ground electrode 30 is located on the other side of the resonance region.

[0059] In some embodiments, the signal lead-out coupling unit 20 includes a first signal electrode 21 and a second signal electrode 22 which are separately arranged, and the signal lead-out coupling unit 20 is electrically connected to a plurality of the signal ends 111 in the resonator unit 11, including: the first signal electrode 21 is electrically connected to a portion of the signal ends 111 in the resonator unit 10, and the second signal electrode 22 is electrically connected to another portion of the signal ends 111 in the resonator unit 10.

[0060] It should be noted that “another portion of the signal ends 111 in the resonator unit 10 are electrically connected” refers to the remaining portion of the signal ends 111 in the resonator unit 10 that are not electrically connected to the first signal electrode 21 .

[0061] In some embodiments, the resonator unit 10 includes at least one first resonator 11a and at least one second resonator 11b, see Figure 3 , Figure 3A schematic diagram of the structure of the first resonator 11a and the second resonator 11b in the resonator unit 10 is shown. The first resonator 11a has a first signal terminal 111a, the second resonator 11b has a second signal terminal 111b, the first signal electrode 21 is electrically connected to the first signal terminal 111a, and the second signal electrode 22 is electrically connected to the second signal terminal 111b, wherein the first signal electrode 21 is used for one of inputting a signal and outputting a signal, and the second signal electrode 22 is used for the other of inputting a signal and outputting a signal. For example, in this embodiment, the first signal electrode 21 is used as an output electrode, and the second signal electrode 22 is used as an input electrode. In other implementations, the first signal electrode 21 can also be used as an input electrode, and the second signal electrode 22 can be used as an output electrode.

[0062] For each resonator 11, in addition to the signal terminal 111 and the ground terminal 112, it also includes two bus bars 114 and interdigital electrodes 113 located between the two bus bars 114. The multiple interdigital electrodes 113 are arranged in a staggered manner and are alternately connected to the two bus bars 114. The signal terminal 111 and the ground terminal 112 extend outward from the sides of the two bus bars 114 that are away from each other (the above-mentioned resonance area is formed by the area between the two bus bars of each resonator extending in the first direction X). Figure 1 As shown, the filter further includes an output port OUT for connecting the first signal electrode 21 to the outside, an input port IN for connecting the second signal electrode 22 to the outside, and a ground port GND for connecting the ground electrode 30 to the outside.

[0063] In some embodiments, Figure 2 As shown, the resonator unit 10 includes a plurality of the first resonators 11a and a plurality of the second resonators 11b, and the plurality of the first resonators 11a and the plurality of the second resonators 11b are arranged alternately. In one embodiment, the number of the first resonators 11a is the same as the number of the second resonators 11b, and in this case, the resonator unit 10 includes an even number of resonators 11. In another embodiment, the number of the first resonators 11a is different from the number of the second resonators 11b, and in this case, the resonator unit 10 includes an odd number of resonators 11. Whether the number of the first resonators 11a and the second resonator 11b is the same and the specific number are selected and set based on the application scenario of the filter, and are not specifically limited here.

[0064] In the embodiment of the present invention, by arranging the signal ends 111 of the plurality of resonators 11 in the resonator unit 10 on the same side and the grounding ends 112 on the same side, the grounding electrode 30 used to realize the grounding of the resonator 11 only needs to be arranged on the side where the grounding ends 112 of each resonator 11 in the resonator unit 10 are located, without arranging a grounding electrode 30 on both opposite sides of the resonator unit 10. Under the condition of the same structural parameters, at least the area occupied by one grounding electrode 30 can be saved, thereby effectively reducing the area of ​​the filter chip and facilitating the miniaturization of the filter volume.

[0065] In some embodiments, please refer to Figure 2 , Figure 4 and Figure 5 ,in, Figure 4 Shows Figure 2 A schematic cross-sectional view of the A-A' region. Figure 5 Shows Figure 2 The first signal electrode 21 spans over the first signal end 111a and the second signal end 111b, and the first signal electrode 21 is electrically isolated from the second signal end 111b.

[0066] In some embodiments, Figure 5 As shown, the filter further includes an isolation structure 40 and an electrical connection structure 50, wherein the isolation structure 40 is located between the first signal electrode 21 and the second signal terminal 111b. The electrical connection structure 50 is located between the first signal electrode 21 and the first signal terminal 111a. The isolation structure 40 is used to achieve electrical isolation between the first signal electrode 21 and the second signal terminal 111b. The electrical connection structure 50 is used to achieve electrical connection between the first signal electrode 21 and the first signal terminal 111a, so as to output the signal emitted by the first resonator 11a (or input a signal to the first resonator 11a).

[0067] In some embodiments, Figure 2 As shown, the filter further includes two reflection gratings 70, which are arranged on both sides of the resonator unit 10 in the first direction X. The two reflection gratings 70 are used to form a resonant cavity to reflect the energy radiated outward by the resonator unit 10, thereby improving the working performance of the filter.

[0068] In some embodiments, Figure 4 and Figure 5 As shown, the filter includes a first metal layer 100, a second metal layer 201, an isolation layer 202 and a third metal layer 300. Figure 6 , Figure 6A schematic diagram of the split structure of the first metal layer 100 in the filter is shown. The first metal layer 100 is divided into a first area 101, a second area 102 and a third area 103 along the second direction Y. The portion of the first metal layer 100 located in the first area 101 includes the ground electrode 30. The portion of the first metal layer 100 located in the second area 102 includes the resonator unit 10. Wherein, in the case where the filter also has the reflection grating 70, the portion of the first metal layer 100 located in the second area 102 also includes the reflection grating 70. The portion of the first metal layer 100 located in the third area 103 includes the second signal electrode 22. Figure 5 As shown, the second metal layer 201 is located above the first metal layer 100, and the second metal layer 201 includes the electrical connection structure 50 connected to the second signal terminal 111b. The isolation layer 202 is distributed in the same layer as the second metal layer 201, and the isolation layer 202 includes the isolation structure 40 covering a portion of the first signal terminal 111a. The third metal layer 300 is located above the isolation layer 202 and the second metal layer 201, and the third metal layer 300 includes the second signal electrode 22 connected to the electrical connection structure 50. That is, the resonator unit 10, the second signal electrode 22 and the ground electrode 30 are distributed in the same layer and can be manufactured synchronously, which helps to save process steps and costs, and can also ensure product yield. The filter also includes a piezoelectric material layer 400, and the first metal layer 100 is located above the piezoelectric material layer 400, so as to realize the working processes such as acoustic wave excitation and propagation based on the piezoelectric material layer 400.

[0069] In some embodiments, please refer to Figure 2 and Figure 7 , Figure 7 Shows Figure 2 The second signal end 111b includes an overlapping portion 1111 and a non-overlapping portion 1112. The overlapping portion 1111 is located below the first signal electrode 21. The isolation structure 40 at least covers the overlapping portion 1111 to isolate the overlapping portion 1111 from the first signal electrode 21.

[0070] In the first direction X, the width w1 of the overlapping portion 1111 is smaller than the width w2 of the non-overlapping portion 1112. It should be noted that the overlapping portion 1111 being located below the first signal electrode 21 means that the vertical projection of the overlapping portion 1111 at least partially overlaps with the vertical projection of the first signal electrode 21, and correspondingly, the non-overlapping portion 1112 refers to the portion of the second signal end 111b whose vertical projection does not overlap with the vertical projection of the first signal electrode 21. Here, the vertical direction refers to a direction perpendicular to the plane formed by the first direction X and the second direction Y.

[0071] In the second direction Y, for example, the overlapping portion 1111 may be located in the middle area of ​​the second signal end 111b, and the non-overlapping portion 1112 may be located in the edge area of ​​the second signal end 111b and on both sides of the overlapping portion 1111. In this case, the second signal end 111b is in an "I" shape. Alternatively, the overlapping portion 1111 is located at one side edge of the second signal end 111b close to the bus bar 114. In this case, the second signal end 111b is in an inverted "T" shape; or alternatively, the overlapping portion 1111 is located at one side edge of the second signal end 111b away from the bus bar 114. In this case, the second signal end 111b is in a "T" shape. Therefore, the specific position of the overlapping portion 1111 in the second signal end 111b and the specific shape of the second signal end 111b are designed based on actual needs, including but not limited to the shapes listed above. Optionally, the overlapping area of ​​the overlapping portion 1111 and the vertical projection of the first signal electrode 21 is greater than or equal to 9 μm 2 , for example, the area is 3 μm×3 μm, or the area is 6 μm×6 μm, etc.

[0072] In the embodiment of the present invention, since the first signal electrode 21 spans over the first signal end 111a and the second signal end 111b, there must be an overlapping area between the first signal electrode 21 and the second signal end 111b. In order to avoid electrical interference and reliability, an isolation structure 40 needs to be provided in the overlapping area between the two. However, due to the manufacturing process limitation of the isolation structure 40, holes or gaps may exist in the isolation structure 40 during the manufacturing process, which affects the electrical isolation effect and thus has the risk of short circuit. Therefore, by designing that the width of the overlapping portion 1111 is smaller than the width of the non-overlapping portion 1112 in the first direction X, the overlapping area between the second signal end 111b and the first signal electrode 21 is minimized as much as possible, thereby reducing the probability of short circuit and improving the working reliability of the filter.

[0073] In some embodiments, the filter further includes at least one of a first coupling capacitor 61, a second coupling capacitor 62, and a third coupling capacitor 63. Figure 5As shown, the first coupling capacitor 61 is formed based on the first signal terminal 111a and the second signal terminal 111b. When no dielectric material is filled between the first signal terminal 111a and the second signal terminal 111b, the capacitor medium of the first coupling capacitor 61 is the environment medium of the filter, for example, air. Figure 5 As shown, the second coupling capacitor 62 is formed based on the second signal terminal 111b, the isolation structure 40 and the first signal electrode 21. Figure 2 and Figure 3 As shown, the third coupling capacitor 63 is formed based on the first signal terminal 111a and the second signal electrode 22. When no dielectric material is filled between the first signal terminal 111a and the second signal electrode 22, the capacitor medium of the third coupling capacitor 63 is the environmental medium of the filter, for example, air. The value of the first coupling capacitor 61 can be adjusted and controlled based on the distance between the first signal terminal 111a and the second signal terminal 111b, the dielectric material filled between the first signal terminal 111a and the second signal terminal 111b, the area directly facing the first signal terminal 111a and the second signal terminal 111b, etc. The value of the second coupling capacitor 62 can be adjusted and controlled based on the overlapping area between the second signal terminal 111b and the first signal electrode 21, the thickness of the isolation structure 40, and the material of the isolation structure 40. The value of the third coupling capacitor 63 can be adjusted and controlled based on the distance between the first signal terminal 111a and the second signal electrode 22, the dielectric material filled between the first signal terminal 111a and the second signal electrode 22, and the area facing each other.

[0074] In the application process of DMS filter, capacitors can be connected in parallel at its input and output ends to improve the rectangularity of the right side of its passband. The rectangularity of the right side of the passband refers to the performance parameter of the filter on the right side of the passband, which characterizes the ability of the filter to transmit signals within the passband and suppress out-of-band interference signals. Improving the rectangularity of the right side of the passband can enable the filter to effectively separate the required signal and the interference signal in practical applications, improve the frequency response characteristics of the filter, and effectively suppress out-of-band interference.

[0075] In the embodiment of the present invention, since the signal ends 111 of adjacent resonators 11 are distributed on the same side, the first signal electrode 21 and the second signal electrode 22 are no longer arranged on both sides of the resonator unit 10, but are arranged on the side of the signal end 111 in the resonator unit 10, so that the distance between the first signal electrode 21 and the second signal electrode 22 is relatively close, and there is a certain coupling capacitance between the two (i.e., the first coupling capacitor 61 to the third coupling capacitor 63), and the value of the coupling capacitance can be conveniently controlled by the structural parameters of the filter itself. The rectangularity of the right side of the filter can be improved without the need for an additional parallel capacitor structure outside the filter structure, which helps to simplify the overall circuit structure of the filter.

[0076] See also Figure 8 , Figure 8 A comparison diagram of S(2,1) transmission coefficient curves of two structures of filters provided by an embodiment of the present invention is shown (the S(2,1) transmission coefficient is the transmission coefficient between the IN port and the OUT port of the filter). Figure 8 The difference between the structure 1 and the structure 2 is that the length of the second signal terminal 111b in the structure 2 is reduced, so that the distance between the second signal electrode 22 and the first signal terminal 111a is reduced (about half the distance), thereby increasing the value of the third coupling capacitor 63. Figure 8 It can be seen from the curve comparison diagram shown that the rectangularity of the right side of the passband of Structure 2 is significantly improved compared with that of the structure, which shows that the rectangularity of the right side of the filter can be effectively improved by adjusting the coupling capacitor in the structure of the filter itself.

[0077] The filter of this embodiment, by adjusting the structure and position distribution of the signal extraction coupling unit and the ground electrode, effectively reduces the area of ​​the filter chip while ensuring the working performance of the filter, and meets the miniaturization reference requirements of the filter. In addition, based on the parameter control of the local structure (signal extraction coupling unit, signal terminal and isolation layer) in the filter, the rectangular degree of the right side of the filter can be adjusted without connecting a capacitor in parallel outside the filter structure, simplifying the circuit structure of the filter. In addition, through the structural design of the second signal terminal, the probability of short circuit in the filter can be reduced, and the reliability of the device can be improved.

[0078] Comparative Example

[0079] See also Fig. 9 , Fig. 9The schematic diagram of the layout structure of a filter provided in the comparative example is shown, and the filter includes a resonator unit 10, an output electrode 20a, an input electrode 20b, a first ground electrode 30a and a second ground electrode 30b, wherein the output electrode 20a and the input electrode 20b are arranged on opposite sides of the resonator unit 10, and the first ground electrode 30a and the second ground electrode 30b are also arranged on opposite sides of the resonator unit 10. Please refer to Fig.10 , Fig.10 It shows a Fig. 9 The structure diagram of the filter is shown in Figure 1. Fig.10 As can be seen from FIG. 1 , the resonator unit 10 includes a plurality of resonators 11. Fig.11 , Fig.11 Shows Fig. 9 The schematic diagram of arrangement of two adjacent resonators in the filter shown is that each resonator 11 includes a signal end 111 and a ground end 112, and the signal ends 111 and the ground ends 112 of two adjacent resonators 11 are arranged in opposite directions, so that along the arrangement direction of the multiple resonators 11, in the resonator unit 10: the signal ends 111 and the ground ends 112 of the multiple resonators 11 are alternately arranged, the output electrode 20a and the input electrode 20b are alternately connected to one end of the multiple resonators 11, and the first ground electrode 30a and the second ground electrode 30b are alternately connected to the other ends of the multiple resonators 11.

[0080] For details, please refer to Figure 1 and Fig. 9 Due to the adjustment of the distribution of the first signal electrode 21, the second signal electrode 22 and the ground electrode 30 in the first embodiment, the area occupied by the filter is effectively reduced (compared with Figure 1 The dashed box and Fig. 9 The area of ​​the dotted box in the figure can be seen. Fig.12 , Fig.12 A comparison diagram of the S(2,1) transmission coefficient curves of the resonators of the first embodiment and the comparative example is shown. While other structural features remain consistent, although the first signal electrode 21 and the second signal electrode 22 are arranged on the same side and only one ground electrode 30 is arranged in this embodiment, there is no difference in basic performance between the filter structure of this embodiment and the filter structure of the comparative example. That is, the filter structure provided in the first embodiment can achieve a reduction in occupied area while ensuring working performance, which meets the requirements of miniaturized application scenarios.

[0081] Please refer to 7 and Fig.13 , Fig.13 Shows Fig.10In the bottom view of the area II in the comparative example, since the width of the input electrode 20b connected to the signal terminal at any position in the second direction Y remains the same, the overlapping area S2 between it and the output electrode 20a is significantly larger than the overlapping area S1 between the second signal terminal 111b and the first signal electrode 21 in the first embodiment ( Figure 7 shown), Fig.12 The S2 shown in FIG. 1 is generally 10 μm×58 μm. This means that the probability of a short circuit between the second signal terminal 111 b and the first signal electrode 21 of the filter of the first embodiment is relatively low, so that the reliability of the filter is relatively high.

[0082] Embodiment 2

[0083] This embodiment provides a method for manufacturing a filter, which can be used to manufacture the filter described in the first embodiment or other suitable filter structures. Figure 2 , Figure 4 and Figure 5 As shown, the manufacturing method comprises the following steps:

[0084] A resonator unit 10 is formed, wherein the resonator unit 10 includes a plurality of resonators 11, wherein the plurality of resonators 11 are arranged in a first direction X, wherein each of the resonators 11 has a signal end 111 and a ground end 112, wherein the signal end 111 and the ground end 112 are opposite to each other in a second direction Y, and the second direction Y intersects with the first direction X;

[0085] A signal extraction coupling unit 20 is formed on the side where the plurality of signal terminals 111 in the resonator unit 10 are located, and the signal extraction coupling unit 20 is electrically connected to the plurality of signal terminals 111 in the resonator unit 10;

[0086] A ground electrode 30 is formed on the side where the plurality of ground terminals 112 in the resonator unit 10 are located, and the ground electrode 30 is electrically connected to the ground terminals 112 of all the resonators 11 .

[0087] In some embodiments, the signal lead-out coupling unit 20 includes a first signal electrode 21 and a second signal electrode 22 which are separately arranged, and the signal lead-out coupling unit 20 is electrically connected to a plurality of the signal ends 111 in the resonator unit 11, including: the first signal electrode 21 is electrically connected to a portion of the signal ends 111 in the resonator unit 10, and the second signal electrode 22 is electrically connected to another portion of the signal ends 111 in the resonator unit 10.

[0088] In some embodiments, the resonator unit 10 , the second signal electrode 22 , and the ground electrode 30 are distributed in the same layer, that is, the three can be manufactured in the same step.

[0089] The filter manufacturing method of this embodiment has simple manufacturing steps and is easy to implement large-scale production.

[0090] Embodiment 3

[0091] This embodiment further provides a wireless communication device, which includes the filter as described in the first embodiment.

[0092] In some embodiments, the wireless communication device includes a duplexer 600. Fig.14 , Fig.14 A topological structure diagram of the duplexer provided in this embodiment is shown. The duplexer 600 includes a transmitting unit (Transmitter, referred to as TX) 601, a receiving unit (Receiver, referred to as RX) 602 and an antenna (Antenna, referred to as ANT) 603, and the antenna 603 is connected between the transmitting unit 601 and the receiving unit 602. Among them, the receiving unit 602 also includes the filter 604, and the transmitting unit 601 and the receiving unit 602 both include a plurality of parallel resonators (Parallel Resonator, referred to as PR) 605 and a plurality of series resonators (Series Resonator, referred to as SR) 606.

[0093] The wireless communication device of this embodiment has the aforementioned filter, the overall area is reduced, and the reliability and working performance are improved, and it is suitable for miniaturized high-performance application scenarios.

[0094] In summary, the filter of the present invention, by adjusting the structure and position distribution of the signal lead-out coupling unit and the ground electrode, effectively reduces the area of ​​the filter chip while ensuring the working performance of the filter, and meets the miniaturization reference requirements of the filter. In addition, based on the parameter control of the local structure (signal lead-out coupling unit, signal terminal and isolation layer) in the filter, the rectangular degree of the right side of the filter can be adjusted without connecting a capacitor in parallel outside the filter structure, thereby simplifying the circuit structure of the filter. In addition, through the structural design of the second signal terminal, the probability of short circuit in the filter can be reduced, and the reliability of the device can be improved. The manufacturing method of the filter of the present invention has simple manufacturing steps and is easy to realize large-scale production. The wireless communication device of the present invention has a small overall area, and has high reliability and working performance, and is suitable for miniaturized high-performance application scenarios. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0095] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0096] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A filter, characterized in that: include: A resonator unit, comprising a plurality of resonators, wherein the plurality of resonators are arranged in a first direction, each of the resonators has a signal end and a ground end, the signal end and the ground end are respectively located at two sides of the resonator in a second direction, and the second direction intersects with the first direction; A signal extraction coupling unit is located at a side where the plurality of signal terminals in the resonator unit are located, and the signal extraction coupling unit is electrically connected to the plurality of signal terminals in the resonator unit; A grounding electrode is located at a side where the multiple grounding ends in the resonator unit are located, and the grounding electrode is electrically connected to the grounding ends of all the resonators.

2. The filter according to claim 1, characterized in that The signal extraction coupling unit includes a first signal electrode and a second signal electrode which are separately arranged. The signal extraction coupling unit is connected to a plurality of signal ends in the resonator unit, including: the first signal electrode is electrically connected to a part of the signal ends in the resonator unit, and the second signal electrode is electrically connected to another part of the signal ends in the resonator unit.

3. The filter according to claim 2, characterized in that: The resonator unit includes at least one first resonator and at least one second resonator, the first resonator has a first signal end, the second resonator has a second signal end, the first signal electrode is electrically connected to the first signal end, and the second signal electrode is electrically connected to the second signal end, wherein the first signal electrode is used for one of inputting a signal and outputting a signal, and the second signal electrode is used for the other of inputting a signal and outputting a signal.

4. The filter according to claim 3, characterized in that: The first signal electrode spans over the first signal end and the second signal end, and the first signal electrode is electrically isolated from the second signal end.

5. The filter according to claim 4, characterized in that: The filter further includes an isolation structure and an electrical connection structure, wherein the isolation structure is located between the first signal electrode and the second signal end, and the electrical connection structure is located between the first signal electrode and the first signal end.

6. The filter according to claim 5, characterized in that: The second signal end includes an overlapping portion and a non-overlapping portion, the overlapping portion is located below the first signal electrode, the isolation structure at least covers the overlapping portion to isolate the overlapping portion from the first signal electrode, and in the first direction, the width of the overlapping portion is smaller than the width of the non-overlapping portion.

7. The filter according to claim 5, characterized in that The filter comprises: A first metal layer is sequentially divided into a first region, a second region, and a third region along the second direction, wherein a portion of the first metal layer located in the first region includes the ground electrode, a portion of the first metal layer located in the second region includes the resonator unit, and a portion of the first metal layer located in the third region includes the second signal electrode; A second metal layer, located above the first metal layer, the second metal layer comprising the electrical connection structure connected to the second signal terminal; An isolation layer, distributed in the same layer as the second metal layer, the isolation layer comprising the isolation structure covering a portion of the first signal terminal; The third metal layer is located above the isolation layer and the second metal layer, and the third metal layer includes the second signal electrode connected to the electrical connection structure.

8. The filter according to claim 3, characterized in that: The filter also includes at least one of a first coupling capacitor, a second coupling capacitor and a third coupling capacitor, the first coupling capacitor is based on the first signal end and the second signal end, the second coupling capacitor is based on the second signal end, the isolation structure and the first signal electrode, and the third coupling capacitor is based on the first signal end and the second signal electrode.

9. The filter according to claim 3, characterized in that The resonator unit includes a plurality of the first resonators and a plurality of the second resonators, and the plurality of the first resonators and the plurality of the second resonators are alternately arranged.

10. A method for manufacturing a filter, characterized in that: Used to manufacture the filter according to any one of claims 1 to 9, the manufacturing method comprises the following steps: forming a resonator unit, the resonator unit comprising a plurality of resonators, the plurality of resonators being arranged in a first direction, each of the resonators having a signal end and a ground end, the signal end and the ground end being opposite to each other in a second direction, the second direction intersecting with the first direction; A signal coupling unit is formed on the side where the plurality of signal ends in the resonator unit are located, and the signal extraction coupling unit is electrically connected to the plurality of signal ends in the resonator unit; A grounding electrode is formed on the side where the multiple grounding ends in the resonator unit are located, and the grounding electrode is electrically connected to the grounding ends of all the resonators.

11. A wireless communication device, characterized in that: The wireless communication device comprises the filter according to any one of claims 1-9.

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