Filter and manufacturing method thereof

Abstract

The invention relates to the technical field of semiconductors, and discloses a filter and a manufacturing method thereof. The filter comprises a substrate, a piezoelectric part, a first temperature compensation layer and / or a second temperature compensation layer, a first electrode, a second electrode, a protection layer, a first bonding pad and a second bonding pad. The piezoelectric part comprises a first side wall surface and a second side wall surface which are arranged back to back. The first temperature compensation layer is arranged on the first side wall surface, and the second temperature compensation layer is arranged on the second side wall surface. The first electrode is arranged on the first side wall surface. The second electrode is arranged on the second side wall surface. The protective layer is arranged on the upper surface of the piezoelectric part and extends outwards to be connected with the substrate after crossing the first electrode and the second electrode, a first cavity is formed in the first side wall face side of the piezoelectric part, and a second cavity is formed in the second side wall face side of the piezoelectric part. The first bonding pad and the second bonding pad are connected with the first electrode and the second electrode in a one-to-one correspondence mode. The temperature drift can be reduced, the reliability can be improved, and the occupied area can be reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, for example, to a filter and a method for manufacturing the same. Background Art

[0002] In the related art, the piezoelectric layer and the electrode layer of the filter are arranged longitudinally on the substrate to realize the longitudinal vibration of the wave, which occupies a large area during packaging.

[0003] In actual application, the filter in the related art still has the problem of large temperature drift.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical elements or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0006] The embodiments of the present disclosure provide a filter and a method for manufacturing the same, which can reduce temperature drift, improve reliability, and reduce occupied area.

[0007] In some embodiments, a filter is provided, comprising: a substrate; a piezoelectric portion, arranged on the upper surface of the substrate, comprising a first side wall surface and a second side wall surface arranged back to back; a first temperature compensation layer and / or a second temperature compensation layer, the first temperature compensation layer being arranged on the first side wall surface of the piezoelectric portion, and the second temperature compensation layer being arranged on the second side wall surface of the piezoelectric portion; a first electrode, arranged on the first side wall surface of the piezoelectric portion, and when the filter comprises the first temperature compensation layer, the first electrode covers the first temperature compensation layer; a second electrode, arranged on the second side wall surface of the piezoelectric portion, and when the filter comprises the second temperature compensation layer, the second electrode covers the second temperature compensation layer; a protective layer, arranged on the upper surface of the piezoelectric portion, and extending outward to respectively cross the first electrode and the second electrode and then connected to the substrate, and forming a first cavity on the first side wall surface side of the piezoelectric portion, and forming a second cavity on the second side wall surface side of the piezoelectric portion; a first soldering pad and a second soldering pad, both arranged on the upper surface of the protective layer, and connected to the first electrode and the second electrode in a one-to-one correspondence.

[0008] Optionally, the lower portion of the first electrode is disposed on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, and the end of the first electrode away from the piezoelectric portion is located inside the protective layer or penetrates outside the protective layer.

[0009] Optionally, one or more piezoelectric parts are provided; when there are multiple piezoelectric parts, the multiple piezoelectric parts are arranged at intervals, and the interval between two adjacent piezoelectric parts is greater than 1 μm.

[0010] Optionally, in the vertical direction, the upper surface of the first electrode is flush with the upper surface of the piezoelectric portion, and the lower surface of the first electrode is flush with the lower surface of the piezoelectric portion; and / or, in the vertical direction, the upper surface of the second electrode is flush with the upper surface of the piezoelectric portion, and the lower surface of the second electrode is flush with the lower surface of the piezoelectric portion. A second preset distance is provided between the lower surface of the second electrode and the lower surface of the piezoelectric portion.

[0011] Optionally, in the vertical direction, there is a third preset spacing between the upper surface of the first temperature compensation layer and the upper surface of the piezoelectric part; and / or, there is a fourth preset spacing between the upper surface of the second temperature compensation layer and the upper surface of the piezoelectric part; and / or, there is a fifth preset spacing between the lower surface of the first temperature compensation layer and the lower surface of the piezoelectric part; and / or, there is a sixth preset spacing between the lower surface of the second temperature compensation layer and the lower surface of the piezoelectric part; in a direction perpendicular to the first side wall surface or the second side wall surface of the piezoelectric part, the thickness of the first temperature compensation layer is the first thickness, and / or, the thickness of the second temperature compensation layer is the second thickness.

[0012] Optionally, the angle between the first side wall surface of the piezoelectric portion and the upper surface of the substrate is 85° to 90°; and / or the angle between the second side wall surface of the piezoelectric portion and the upper surface of the substrate is 85° to 90°.

[0013] In some embodiments, a method for manufacturing a filter is also provided, which is used to manufacture the above-mentioned filter, and the manufacturing method includes: forming a piezoelectric portion on the upper surface of a substrate, the piezoelectric portion including a first side wall surface and a second side wall surface arranged back to back; forming a first temperature compensation layer on the first side wall surface, and / or forming a second temperature compensation layer on the second side wall surface; forming a first electrode on the first side wall surface of the piezoelectric portion, and when the filter includes the first temperature compensation layer, the first electrode covers the first temperature compensation layer; forming a second electrode on the second side wall surface of the piezoelectric portion, and when the filter includes the second temperature compensation layer, the second electrode covers the second temperature compensation layer; forming a sacrificial layer on the upper surface of the substrate, so that the upper surfaces of the sacrificial layer, the piezoelectric portion and the second electrode are flush, and the sacrificial layer covers the first electrode; forming a protective layer on the substrate, the protective layer covers the sacrificial layer, the piezoelectric portion and the second electrode; forming a first pad and a second pad on the upper surface of the protective layer, and connecting the first pad to the first electrode, and the second pad to the second electrode; removing the sacrificial layer to form a first cavity on the first side wall surface side of the piezoelectric portion and a second cavity on the second side wall surface side of the piezoelectric portion.

[0014] Optionally, the step of forming a first temperature compensation layer on the first side wall surface and / or the step of forming a second temperature compensation layer on the second side wall surface includes: depositing a temperature compensation layer on the upper surface of the substrate and the surface of the piezoelectric part; etching the temperature compensation layer to obtain a first temperature compensation layer of a first target size and / or a second temperature compensation layer of a second target size.

[0015] Optionally, the lower portion of the first electrode is arranged on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, the end of the first electrode on the side away from the piezoelectric portion is located inside the protective layer, a first pad and a second pad are formed on the upper surface of the protective layer, and the first pad is connected to the first electrode, and the step of connecting the second pad to the second electrode includes: forming a first filling hole in the protective layer and the sacrificial layer, the first filling hole exposing the end of the first electrode on the side away from the piezoelectric portion; forming a second filling hole in the protective layer, the second filling hole exposing the upper surface of the second electrode; forming a metal layer in the first filling hole, and making the metal layer cover the upper surface of the protective layer surrounding the first filling hole to form a first pad, and realize the connection between the first pad and the first electrode; forming a metal layer in the second filling hole, and making the metal layer cover the upper surface of the protective layer surrounding the second filling hole to form a second pad, and realize the connection between the second pad and the second electrode.

[0016] Optionally, the lower portion of the first electrode is arranged on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, and the end of the first electrode on the side away from the piezoelectric portion is penetrated to the outside of the protective layer, and a first pad and a second pad are formed on the upper surface of the protective layer, and the first pad is connected to the first electrode, and the step of connecting the second pad to the second electrode includes: forming a second filling hole in the protective layer, the second filling hole exposing the upper surface of the second electrode; forming a metal layer in a vertical direction of the end of the first electrode on the side away from the piezoelectric portion, and the metal layer covers a portion of the upper surface of the protective layer to form a first pad, and realize the connection between the first pad and the first electrode; forming a metal layer in the second filling hole, and the metal layer covers the upper surface of the protective layer surrounding the second filling hole to form a second pad, and realize the connection between the second pad and the second electrode.

[0017] The filter and the manufacturing method thereof provided by the embodiments of the present disclosure can achieve the following technical effects: In the filter disclosed in the present invention, the piezoelectric part is arranged on the upper surface of the substrate, the piezoelectric part includes a first side wall surface and a second side wall surface arranged in a back-to-back manner, the first electrode is arranged on the first side wall surface of the piezoelectric part, and the second electrode is arranged on the second side wall surface of the piezoelectric part, so that the first electrode, the piezoelectric part and the second electrode are arranged horizontally to achieve lateral vibration of the wave. The first temperature compensation layer is arranged on the first side wall surface of the piezoelectric part. When the filter includes the first temperature compensation layer, the first electrode covers the first temperature compensation layer, that is, the first temperature compensation layer is added between the piezoelectric part and the first electrode, so as to reduce temperature drift and improve reliability. The second temperature compensation layer is arranged on the second side wall surface of the piezoelectric part. When the filter includes the second temperature compensation layer, the second electrode covers the second temperature compensation layer, that is, the second temperature compensation layer is added between the piezoelectric part and the second electrode, so as to reduce temperature drift and improve reliability. The protective layer is arranged on the upper surface of the piezoelectric part, and the protective layer extends outward to cross the first electrode and the second electrode respectively and then connects to the substrate, and forms a first cavity on the first side wall surface of the piezoelectric part, and forms a second cavity on the second side wall surface of the piezoelectric part, which can improve the vibration performance and realize the lateral vibration of the wave. The filter disclosed in the present invention has a simple structure, can reduce temperature drift, improve reliability, and can reduce the occupied area, so that the number of packages can be increased during packaging, and the manufacturing cost can be reduced.

[0018] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein: Figure 1 is a schematic diagram of a cross-sectional structure of a filter provided by an embodiment of the present disclosure; Figure 2 is a schematic cross-sectional structure diagram of a filter provided by another embodiment of the present disclosure; Figure 3 is a top view schematic diagram of a plurality of piezoelectric parts provided by an embodiment of the present disclosure being arranged on a substrate; Figure 4 is a schematic flow chart of a method for manufacturing a filter provided by an embodiment of the present disclosure; Figure 5 is a flow chart of a method for manufacturing a filter provided by another embodiment of the present disclosure; Figure 6 is a flow chart of a method for manufacturing a filter provided by yet another embodiment of the present disclosure; Figure 7 is a schematic diagram of a structure in which a piezoelectric layer is deposited on an upper surface of a substrate provided by an embodiment of the present disclosure; Figure 8 It is etching Figure 7 A schematic diagram of the structure of a piezoelectric portion obtained from a piezoelectric layer in the illustrated embodiment; Fig. 9 is Figure 8 A schematic diagram of the structure of a temperature compensation layer deposited on the surface of the structure of the illustrated embodiment; Fig.10 It is etching Fig. 9 The temperature compensation layer in the embodiment shown is a schematic diagram of the structure of a first temperature compensation layer and a second temperature compensation layer; Fig.11 is Fig.10 A schematic diagram of the structure of the surface deposited electrode layer of the structure of the illustrated embodiment; Fig.12 It is etching Fig.11 A schematic structural diagram of a portion of an electrode layer of the illustrated embodiment; Fig.13 It is etching Fig.12 A schematic diagram of the structure of obtaining a first electrode and a second electrode from the electrode layer of the embodiment shown; Fig.14 is Fig.13 A schematic diagram of the structure of the embodiment shown in which a sacrificial layer is deposited on the surface of the structure; Fig.15 An embodiment of the present disclosure provides Fig.14 Schematic diagram of the structure of the sacrificial layer after chemical mechanical polishing; Fig.16 is Fig.15 A schematic diagram of the structure of the surface deposited protective layer of the structure of the illustrated embodiment; Fig.17 is Fig.16 A schematic diagram of the structure of the embodiment shown in which a first filling hole and a second filling hole are formed; Fig.18 is Fig.17 A schematic diagram of the structure of the embodiment shown forms a first pad and a second pad; Fig.19 Another embodiment of the present disclosure provides Fig.14 Schematic diagram of the structure of the sacrificial layer after chemical mechanical polishing; Fig. 20 is Fig.19 A schematic diagram of the structure of the surface deposited protective layer of the structure of the illustrated embodiment; Fig.21 is Fig. 20 A schematic diagram of a structure in which a second filling hole is formed by the structure of the illustrated embodiment; Fig. 22 is Fig.21The structure of the illustrated embodiment is a schematic diagram of a structure in which a first pad and a second pad are formed.

[0020] Reference numerals: 100: filter; 101: substrate; 102: piezoelectric part; 1021: first side wall surface; 1022: second side wall surface; 103: first piezoelectric part; 104: second piezoelectric part; 105: third piezoelectric part; 106: piezoelectric layer; 107: first temperature compensation layer; 108: second temperature compensation layer; 109: temperature compensation layer; 110: first electrode; 111: second electrode; 112: electrode layer; 113: protective layer; 114: first solder pad; 115: second solder pad; 116: metal layer; 117: first cavity; 118: second cavity; 119: sacrificial layer; 120: first filling hole; 121: second filling hole; 122: fourth piezoelectric part. DETAILED DESCRIPTION

[0021] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0022] The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0023] In the embodiments of the present disclosure, the terms "upper", "lower", "inside", "middle", "outside", "front", "back" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are mainly intended to better describe the embodiments of the present disclosure and their embodiments, and are not intended to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction. Moreover, in addition to being used to indicate directions or positional relationships, some of the above terms may also be used to indicate other meanings. For example, the term "upper" may also be used to indicate a certain dependency or connection relationship in certain circumstances. For those of ordinary skill in the art, the specific meanings of these terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0024] In addition, the terms "disposed", "connected", and "fixed" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0025] Unless otherwise stated, the term "plurality" means two or more.

[0026] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.

[0027] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

[0029] Combination Figure 1 and Figure 2 As shown, the embodiment of the present disclosure provides a filter 100. The filter 100 includes a substrate 101, a piezoelectric portion 102, a first temperature compensation layer 107, a second temperature compensation layer 108, a first electrode 110, a second electrode 111, a protective layer 113, a first pad 114, and a second pad 115. The piezoelectric portion 102 is disposed on the upper surface of the substrate 101, and the piezoelectric portion 102 includes a first side wall surface 1021 and a second side wall surface 1022 disposed in opposite directions. The first temperature compensation layer 107 is disposed on the first side wall surface 1021 of the piezoelectric portion 102. The second temperature compensation layer 108 is disposed on the second side wall surface 1022 of the piezoelectric portion 102. The first electrode 110 is disposed on the first side wall surface 1021 of the piezoelectric portion 102, and the first electrode 110 covers the first temperature compensation layer 107. The second electrode 111 is disposed on the second side wall surface 1022 of the piezoelectric portion 102, and the second electrode 111 covers the second temperature compensation layer 108. The protective layer 113 is disposed on the upper surface of the piezoelectric portion 102, and the protective layer 113 extends outward to cross the first electrode 110 and the second electrode 111 respectively and then connects to the substrate 101, and forms a first cavity 117 on the first side wall surface 1021 of the piezoelectric portion 102, and forms a second cavity 118 on the second side wall surface 1022 of the piezoelectric portion 102. The first pad 114 and the second pad 115 are both disposed on the upper surface of the protective layer 113, and the first pad 114 and the second pad 115 are connected to the first electrode 110 and the second electrode 111 in a one-to-one correspondence.

[0030] In this embodiment, the piezoelectric portion 102 is disposed on the upper surface of the substrate 101, and the piezoelectric portion 102 includes a first side wall surface 1021 and a second side wall surface 1022 disposed opposite to each other. Figure 1 and Figure 2 As shown, the first side wall surface 1021 is the left side wall surface of the piezoelectric portion 102, and the second side wall surface 1022 is the right side wall surface of the piezoelectric portion 102. In addition, the first side wall surface 1021 and the second side wall surface 1022 are both adjacent to the upper surface of the substrate 101 to achieve the lateral arrangement of the first electrode 110, the piezoelectric portion 102, and the second electrode 111, so as to achieve the lateral vibration of the wave.

[0031] In this embodiment, the first temperature compensation layer 107 is disposed on the first side wall surface 1021 of the piezoelectric portion 102. The second temperature compensation layer 108 is disposed on the second side wall surface 1022 of the piezoelectric portion 102. Both the first temperature compensation layer 107 and the second temperature compensation layer 108 are used to reduce temperature drift.

[0032] In this embodiment, the first electrode 110 is disposed on the first side wall surface 1021 of the piezoelectric portion 102, and the first electrode 110 covers the first temperature compensation layer 107. That is, the first temperature compensation layer 107 is added between the piezoelectric portion 102 and the first electrode 110 to reduce temperature drift and improve reliability. The second electrode 111 is disposed on the second side wall surface 1022 of the piezoelectric portion 102, and the second electrode 111 covers the second temperature compensation layer 108. That is, the second temperature compensation layer 108 is added between the piezoelectric portion 102 and the second electrode 111 to reduce temperature drift and improve reliability.

[0033] In this embodiment, the protective layer 113 is arranged on the upper surface of the piezoelectric part 102, and the protective layer 113 extends outward to cross the first electrode 110 and the second electrode 111 respectively and then connects to the substrate 101, and forms a first cavity 117 on the first side wall surface 1021 of the piezoelectric part 102, and forms a second cavity 118 on the second side wall surface 1022 of the piezoelectric part 102, which can improve the vibration performance and realize the lateral vibration of the wave.

[0034] In the related art, the piezoelectric layer and electrode layer of the filter are arranged longitudinally on the substrate, and the wave of the filter vibrates longitudinally, resulting in a complex structure and process of the filter, and the filter occupies a large area. When packaging, the number of packages is reduced and the manufacturing cost is increased. Compared with the related art, the filter 100 of this embodiment has a simple structure and process. In addition, the first temperature compensation layer 107 and the second temperature compensation layer 108 can reduce temperature drift and improve reliability. The horizontal arrangement of the first electrode 110, the piezoelectric part 102 and the second electrode 111 can reduce the occupied area, increase the number of packages during packaging, and reduce manufacturing costs.

[0035] The embodiment of the present disclosure also provides a filter 100. The filter 100 includes a substrate 101, a piezoelectric portion 102, a first temperature compensation layer 107, a first electrode 110, a second electrode 111, a protective layer 113, a first pad 114, and a second pad 115. The piezoelectric portion 102 is disposed on the upper surface of the substrate 101, and the piezoelectric portion 102 includes a first side wall surface 1021 and a second side wall surface 1022 disposed in opposite directions. The first temperature compensation layer 107 is disposed on the first side wall surface 1021 of the piezoelectric portion 102. The first electrode 110 is disposed on the first side wall surface 1021 of the piezoelectric portion 102, and the first electrode 110 covers the first temperature compensation layer 107. The second electrode 111 is disposed on the second side wall surface 1022 of the piezoelectric portion 102. The protective layer 113 is disposed on the upper surface of the piezoelectric portion 102, and the protective layer 113 extends outward to cross the first electrode 110 and the second electrode 111 respectively and then connects to the substrate 101, and forms a first cavity 117 on the first side wall surface 1021 of the piezoelectric portion 102, and forms a second cavity 118 on the second side wall surface 1022 of the piezoelectric portion 102. The first pad 114 and the second pad 115 are both disposed on the upper surface of the protective layer 113, and the first pad 114 and the second pad 115 are connected to the first electrode 110 and the second electrode 111 in a one-to-one correspondence.

[0036] In this embodiment, the structure and process of the filter 100 are simple. The first temperature compensation layer 107 can reduce temperature drift and improve reliability. The first electrode 110, the piezoelectric part 102 and the second electrode 111 are arranged horizontally to reduce the occupied area, increase the number of packages during packaging, and reduce manufacturing costs.

[0037] The embodiment of the present disclosure also provides a filter 100. The filter 100 includes a substrate 101, a piezoelectric portion 102, a second temperature compensation layer 108, a first electrode 110, a second electrode 111, a protective layer 113, a first pad 114, and a second pad 115. The piezoelectric portion 102 is disposed on the upper surface of the substrate 101, and the piezoelectric portion 102 includes a first side wall surface 1021 and a second side wall surface 1022 disposed in opposite directions. The second temperature compensation layer 108 is disposed on the second side wall surface 1022 of the piezoelectric portion 102. The first electrode 110 is disposed on the first side wall surface 1021 of the piezoelectric portion 102. The second electrode 111 is disposed on the second side wall surface 1022 of the piezoelectric portion 102, and the second electrode 111 covers the second temperature compensation layer 108. The protective layer 113 is disposed on the upper surface of the piezoelectric portion 102, and the protective layer 113 extends outward to cross the first electrode 110 and the second electrode 111 respectively and then connects to the substrate 101, and forms a first cavity 117 on the first side wall surface 1021 of the piezoelectric portion 102, and forms a second cavity 118 on the second side wall surface 1022 of the piezoelectric portion 102. The first pad 114 and the second pad 115 are both disposed on the upper surface of the protective layer 113, and the first pad 114 and the second pad 115 are connected to the first electrode 110 and the second electrode 111 in a one-to-one correspondence.

[0038] In this embodiment, the structure and process of the filter 100 are simple. The second temperature compensation layer 108 can reduce temperature drift and improve reliability. The first electrode 110, the piezoelectric part 102 and the second electrode 111 are arranged horizontally to reduce the occupied area, increase the number of packages during packaging, and reduce manufacturing costs.

[0039] Combination Figure 1 and Figure 2 As shown, in some embodiments, the lower portion of the first electrode 110 is disposed on the upper surface of the substrate 101, the lower portion of the first electrode 110 extends in a direction away from the piezoelectric portion 102, and the end of the first electrode 110 on the side away from the piezoelectric portion 102 is located inside the protective layer 113 or penetrates to the outside of the protective layer 113.

[0040] In this embodiment, the lower portion of the first electrode 110 is arranged on the upper surface of the substrate 101, and the lower portion of the first electrode 110 extends in a direction away from the piezoelectric portion 102. The end of the first electrode 110 on the side away from the piezoelectric portion 102 is located inside the protective layer 113, that is, the protective layer 113 spans the entire first electrode 110, the piezoelectric portion 102 and the second electrode 111, thereby improving the vibration performance.

[0041] In this embodiment, the lower portion of the first electrode 110 is arranged on the upper surface of the substrate 101, and the lower portion of the first electrode 110 extends in a direction away from the piezoelectric portion 102. The end of the first electrode 110 on the side away from the piezoelectric portion 102 is passed through to the outside of the protective layer 113, that is, the protective layer 113 spans a portion of the first electrode 110, the piezoelectric portion 102 and the second electrode 111, thereby improving the vibration performance while reducing energy loss and improving the structural stability.

[0042] Combination Figures 1 to 3 As shown, in some embodiments, there are one or more piezoelectric parts 102. When there are multiple piezoelectric parts 102, the multiple piezoelectric parts 102 are arranged at intervals, and the interval between two adjacent piezoelectric parts 102 is greater than 1 μm.

[0043] In this embodiment, when a plurality of piezoelectric portions 102 are provided, the plurality of piezoelectric portions 102 are arranged at intervals, and the interval between two adjacent piezoelectric portions 102 is greater than 1 μm, which can improve vibration performance and save area.

[0044] Optionally, combined Figure 3 As shown, the outline shape of the piezoelectric portion 102 includes a regular shape, such as a circle, a square, or a triangle.

[0045] Optionally, combined Figure 3 As shown, the contour shape of the piezoelectric portion 102 includes an irregular shape, such as an irregular arc or an irregular polygon.

[0046] Optionally, combined Figure 3 As shown, the outline shape of the piezoelectric portion 102 includes a closed shape, such as a circle or an irregular polygon.

[0047] Optionally, combined Figure 3 As shown, the outline shape of the piezoelectric portion 102 includes an open shape, such as a regular arc (such as a semicircle) or an irregular arc.

[0048] Optionally, combined Figure 3 As shown, on the outline of the same piezoelectric portion 102 , the distance between the two closest positions is greater than 1 μm to improve the vibration performance.

[0049] Exemplary: like Figure 3 As shown, Figure 3 is a top view schematic diagram of four piezoelectric parts 102 arranged on the substrate 101. For the convenience of description, Figure 3The four piezoelectric parts 102 in the figure are respectively described as the first piezoelectric part 103, the second piezoelectric part 104, the third piezoelectric part 105 and the fourth piezoelectric part 122. The contour shape of the first piezoelectric part 103 is an irregular arc, the contour shape of the second piezoelectric part 104 is an ellipse, the contour shape of the third piezoelectric part 105 is a square, and the contour shape of the fourth piezoelectric part 122 is an ellipse. The second piezoelectric part 104 is arranged on the inner side of the fourth piezoelectric part 122. By embedding and matching the second piezoelectric part 104 and the fourth piezoelectric part 122, the occupied area can be saved. The spacing A between the first piezoelectric part 103, the second piezoelectric part 104, the third piezoelectric part 105 and the fourth piezoelectric part 122 is greater than 1μm. On the contour of the third piezoelectric part 105, the spacing C between the two closest positions is greater than 1μm.

[0050] In this example, when the first side wall surface 1021 and the second side wall surface 1022 of the first piezoelectric portion 103 are both perpendicular to the upper surface of the substrate 101, the first piezoelectric portion 103 and the substrate 101 at any position of the first piezoelectric portion 103 are cut along a direction perpendicular to the first side wall surface 1021 or the second side wall surface 1022 at the position, and the following can be obtained: Figure 8 The structure shown.

[0051] In this example, when the first side wall surface 1021 and the second side wall surface 1022 of the second piezoelectric portion 104 are both perpendicular to the upper surface of the substrate 101, the second piezoelectric portion 104 and the substrate 101 at any position of the second piezoelectric portion 104 are cut along a direction perpendicular to the first side wall surface 1021 or the second side wall surface 1022, and the following can be obtained: Figure 8 The structure shown.

[0052] In this example, when the first side wall surface 1021 and the second side wall surface 1022 of the third piezoelectric portion 105 are both perpendicular to the upper surface of the substrate 101, the third piezoelectric portion 105 and the substrate 101 at any position are cut along a direction perpendicular to the first side wall surface 1021 or the second side wall surface 1022 of the third piezoelectric portion 105, and the following can be obtained: Figure 8 The structure shown.

[0053] In this example, when the first side wall surface 1021 and the second side wall surface 1022 of the fourth piezoelectric portion 122 are both perpendicular to the upper surface of the substrate 101, the fourth piezoelectric portion 122 and the substrate 101 at any position are cut along a direction perpendicular to the first side wall surface 1021 or the second side wall surface 1022 of the fourth piezoelectric portion 122, and the following can be obtained: Figure 8 The structure shown.

[0054] In this example, the second piezoelectric portion 104 is disposed inside the fourth piezoelectric portion 122, and at adjacent positions of the second piezoelectric portion 104 and the fourth piezoelectric portion 122 (eg, Figure 3 When the second piezoelectric portion 104 and the fourth piezoelectric portion 122 are cut along the dotted line, the cavity between the second piezoelectric portion 104 and the fourth piezoelectric portion 122 can be shared, further saving the occupied area. That is, when the second piezoelectric portion 104 and the fourth piezoelectric portion 122 are applied to the filter 100, Figure 3 The middle dashed line cuts the filter 100, and the second piezoelectric portion 104 has a first cavity 117 on the first side wall 1021 side, and the second piezoelectric portion 104 has a second cavity 118 on the second side wall 1022 side. The fourth piezoelectric portion 122 has a first cavity 117 on the first side wall 1021 side, and the fourth piezoelectric portion 122 has a second cavity 118 on the second side wall 1022 side. The second cavity 118 on the second side wall 1022 side of the second piezoelectric portion 104 and the first cavity 117 on the first side wall 1021 side of the fourth piezoelectric portion 122 can share one, so as to save the occupied area, increase the number of packages during packaging, and reduce the manufacturing cost.

[0055] Combination Figure 1 , Figure 2 and Fig.13 As shown, in some embodiments, in the vertical direction, there is a first preset distance (eg, Fig.13 In the embodiment of the present invention, the lower surface of the first electrode 110 is flush with the lower surface of the piezoelectric portion 102. And / or, in the vertical direction, the upper surface of the second electrode 111 is flush with the upper surface of the piezoelectric portion 102, and there is a second preset distance (such as L1) between the lower surface of the second electrode 111 and the lower surface of the piezoelectric portion 102. Fig.13 in L2).

[0056] In this embodiment, in the vertical direction, there is a first preset distance (eg, Fig.13 , that is, the upper surface of the first electrode 110 is lower than the upper surface of the piezoelectric portion 102 to improve the vibration performance.

[0057] In this embodiment, in the vertical direction, the upper surface of the second electrode 111 is flush with the upper surface of the piezoelectric portion 102, and a second preset distance (eg, Fig.13 , that is, the lower surface of the second electrode 111 is higher than the lower surface of the piezoelectric portion 102 (that is, the upper surface of the substrate 101) to improve the vibration performance.

[0058] In this embodiment, the specific values ​​of the first preset spacing and the second preset spacing are not limited and are determined according to actual conditions. For example, the first preset spacing L1 is 0.1 μm to 0.4 μm. For another example, the second preset spacing L2 is 0.1 μm to 0.4 μm.

[0059] Combination Figure 1 , Figure 2 and Fig.10 As shown, in some embodiments, in the vertical direction, there is a third preset spacing between the upper surface of the first temperature compensation layer and the upper surface of the piezoelectric portion. And / or, there is a fourth preset spacing between the upper surface of the second temperature compensation layer and the upper surface of the piezoelectric portion. And / or, there is a fifth preset spacing between the lower surface of the first temperature compensation layer and the lower surface of the piezoelectric portion. And / or, there is a sixth preset spacing between the lower surface of the second temperature compensation layer and the lower surface of the piezoelectric portion. In a direction perpendicular to the first side wall surface or the second side wall surface of the piezoelectric portion, the thickness of the first temperature compensation layer is the first thickness. And / or, the thickness of the second temperature compensation layer is the second thickness.

[0060] In this embodiment, in the vertical direction, there is a third preset distance (eg, Fig.10 There is a fourth preset distance (such as L3 in FIG. 1 ) between the upper surface of the second temperature compensation layer 108 and the upper surface of the piezoelectric portion 102. Fig.10 There is a fifth preset distance (eg, L4) between the lower surface of the first temperature compensation layer 107 and the lower surface of the piezoelectric portion 102. Fig.10 There is a sixth preset distance (eg, L5) between the lower surface of the second temperature compensation layer 108 and the lower surface of the piezoelectric portion 102. Fig.10 L6 in the figure). This can reduce temperature drift and improve reliability.

[0061] In this embodiment, in a direction perpendicular to the first side wall surface 1021 or the second side wall surface 1022 of the piezoelectric portion 102 (when the first side wall surface 1021 and the second side wall surface 1022 are both perpendicular to the upper surface of the substrate 101, the direction perpendicular to the first side wall surface 1021 and the second side wall surface 1022 of the piezoelectric portion 102 may be), the thickness of the first temperature compensation layer 107 is a first thickness (such as Fig.10 The thickness of the second temperature compensation layer 108 is a second thickness (eg Fig.10 L8 in the circuit) to reduce temperature drift and improve reliability.

[0062] In this embodiment, the specific values ​​of the third preset spacing, the fourth preset spacing, the fifth preset spacing, and the sixth preset spacing are not limited and are determined according to actual conditions. For example, the third preset spacing L3 is 0.5 μm to 1 μm. For another example, the fourth preset spacing L4 is 0.5 μm to 1 μm. For another example, the fifth preset spacing L5 is 0.5 μm to 1 μm. For another example, the sixth preset spacing L6 is 0.5 μm to 1 μm.

[0063] In this embodiment, the specific values ​​of the first thickness and the second thickness are not limited and are determined according to actual conditions. For example, the first thickness L7 is 10 nm to 500 nm. For another example, the second thickness L8 is 10 nm to 500 nm.

[0064] Optionally, in the vertical direction, the first electrode 110 covers the first temperature compensation layer 107 , and the distance between the upper surface of the first temperature compensation layer 107 and the upper surface of the first electrode 110 ranges from 0.1 μm to 0.9 μm, so as to reduce temperature drift.

[0065] Optionally, in the vertical direction, the distance between the lower surface of the second temperature compensation layer 108 and the lower surface of the second electrode 111 ranges from 0.1 μm to 0.9 μm, so as to reduce the temperature drift.

[0066] Combination Figure 8 As shown, in some embodiments, the angle between the first side wall surface 1021 of the piezoelectric portion 102 and the upper surface of the substrate 101 is 85° to 90°. And / or, the angle between the second side wall surface 1022 of the piezoelectric portion 102 and the upper surface of the substrate 101 is 85° to 90°.

[0067] In this embodiment, the angle between the first side wall surface 1021 of the piezoelectric portion 102 and the upper surface of the substrate 101 (eg Figure 8 The angle α in FIG. 1 is 85° to 90°, so as to improve the stability of the piezoelectric portion 102 being disposed on the substrate 101 .

[0068] In this embodiment, the angle between the second side wall surface 1022 of the piezoelectric portion 102 and the upper surface of the substrate 101 is ( Figure 8 The angle β in the embodiment is 85° to 90°, so as to improve the stability of the piezoelectric portion 102 being disposed on the substrate 101.

[0069] Optionally, the angle between the first side wall surface 1021 of the piezoelectric portion 102 and the upper surface of the substrate 101 is 85°, 86°, 87°, 88°, 89°, 90° or other values ​​between 85° and 90°.

[0070] Optionally, the angle between the second side wall surface 1022 of the piezoelectric portion 102 and the upper surface of the substrate 101 is 85°, 86°, 87°, 88°, 89°, 90° or other values ​​between 85° and 90°.

[0071] Combination Figure 4 As shown, the embodiment of the present disclosure further provides a method for manufacturing a filter, which is used to manufacture the filter 100 described above, and the manufacturing method includes: S401, such as Figure 8 As shown, a piezoelectric portion is formed on the upper surface of the substrate, and the piezoelectric portion includes a first side wall surface and a second side wall surface arranged in opposite directions.

[0072] In this embodiment, a piezoelectric portion 102 is formed on the upper surface of the substrate 101 . The piezoelectric portion 102 includes a first side wall surface 1021 and a second side wall surface 1022 disposed opposite to each other, providing a basis for the lateral arrangement of the first electrode 110 , the piezoelectric portion 102 and the second electrode 111 .

[0073] Optionally, forming the piezoelectric portion 102 on the upper surface of the substrate 101 is achieved by: Figure 7 As shown, a piezoelectric layer 106 is deposited on the upper surface of the substrate 101. Figure 8 As shown, the piezoelectric layer 106 is etched to obtain the piezoelectric portion 102 with a target contour shape.

[0074] It is understandable that the target contour shape of the piezoelectric portion 102 is not limited, for example, a regular shape or an irregular shape.

[0075] It can be understood that the specific size of the piezoelectric part 102 is set according to needs and is not limited here.

[0076] Optionally, the substrate 101 includes a silicon substrate 101 .

[0077] Optionally, the material of the piezoelectric portion 102 includes single crystal silicon.

[0078] Optionally, the material of the piezoelectric portion 102 includes polysilicon.

[0079] Optionally, the material of the piezoelectric portion 102 includes aluminum nitride (ALN).

[0080] Optionally, the material of the piezoelectric portion 102 includes scandium-doped aluminum nitride (ALScN).

[0081] Optionally, the material of the piezoelectric portion 102 includes quartz.

[0082] S402 , forming a first temperature compensation layer on the first side wall surface, and / or forming a second temperature compensation layer on the second side wall surface.

[0083] In this embodiment, a first temperature compensation layer 107 is formed on the first side wall surface 1021 of the piezoelectric portion 102 to reduce temperature drift.

[0084] In this embodiment, a second temperature compensation layer 108 is formed on the second side wall surface 1022 of the piezoelectric portion 102 to reduce temperature drift.

[0085] Optionally, the material of the first temperature compensation layer 107 includes undoped silicon glass (USG).

[0086] Optionally, the material of the first temperature compensation layer 107 includes phosphate glass (PSG).

[0087] Optionally, the material of the first temperature compensation layer 107 includes silicon nitride (SIN).

[0088] Optionally, the material of the second temperature compensation layer 108 includes undoped silicon glass (USG).

[0089] Optionally, the material of the second temperature compensation layer 108 includes phosphate glass (PSG).

[0090] Optionally, the material of the second temperature compensation layer 108 includes silicon nitride (SIN).

[0091] S403, forming a first electrode on the first side wall surface of the piezoelectric portion, and when the filter includes a first temperature compensation layer, the first electrode covers the first temperature compensation layer; forming a second electrode on the second side wall surface of the piezoelectric portion, and when the filter includes a second temperature compensation layer, the second electrode covers the second temperature compensation layer.

[0092] In this embodiment, the first electrode 110 is formed on the first side wall surface 1021 of the piezoelectric portion 102 . When the filter 100 includes the first temperature compensation layer 107 , the first electrode 110 covers the first temperature compensation layer 107 to reduce temperature drift and improve reliability.

[0093] In this embodiment, the second electrode 111 is formed on the second side wall surface 1022 of the piezoelectric portion 102 . When the filter 100 includes the second temperature compensation layer 108 , the second electrode 111 covers the second temperature compensation layer 108 to reduce temperature drift and improve reliability.

[0094] In this embodiment, by arranging the first electrode 110 , the piezoelectric portion 102 , and the second electrode 111 in a transverse manner, the transverse vibration of the wave is achieved, and the process is simple.

[0095] Optionally, forming a first electrode on a first side wall surface of the piezoelectric portion and forming a second electrode on a second side wall surface of the piezoelectric portion can be achieved by: Fig.11As shown, an electrode layer 112 is deposited on the upper surface of the substrate 101 and the surfaces of the piezoelectric portion 102, the first temperature compensation layer 107 and the second temperature compensation layer 108. Fig.12 As shown, the electrode layer 112 is etched to complete the lower processing of the first electrode 110 and the upper surface processing of the second electrode 111. Fig.13 As shown, the electrode layer 112 is further etched to complete the upper surface processing of the first electrode 110 and the lower processing of the second electrode 111 to obtain the first electrode 110 and the second electrode 111.

[0096] Optionally, the material of the first electrode 110 includes molybdenum (Mo).

[0097] Optionally, the material of the first electrode 110 includes tungsten (W).

[0098] Optionally, the material of the second electrode 111 includes molybdenum (Mo).

[0099] Optionally, the material of the second electrode 111 includes tungsten (W).

[0100] S404, forming a sacrificial layer on the upper surface of the substrate, so that the upper surfaces of the sacrificial layer, the piezoelectric portion and the second electrode are flush, and the sacrificial layer covers the first electrode.

[0101] In this embodiment, a sacrificial layer 119 is formed on the upper surface of the substrate 101 to provide support for forming the protection layer 113 .

[0102] In this embodiment, Fig.15 As shown, the sacrificial layer 119 covers the entire first electrode 110 so that the end of the first electrode 110 away from the piezoelectric portion 102 is located inside the protective layer 113 to improve vibration performance.

[0103] In this embodiment, Fig.19 As shown, the sacrificial layer 119 covers a portion of the first electrode 110 so that the end of the first electrode 110 away from the piezoelectric portion 102 is extended to the outside of the protective layer 113 to reduce energy loss and improve structural stability.

[0104] Optionally, a sacrificial layer 119 is formed on the upper surface of the substrate 101 by: Fig.14 As shown, a sacrificial layer 119 is deposited on the upper surface of the substrate 101. Fig.15 and Fig.19 As shown, chemical mechanical polishing (CMP) is performed on the sacrificial layer 119 to improve the flatness and thickness uniformity of the sacrificial layer 119 , thereby improving the performance of the filter 100 .

[0105] Optionally, the sacrificial layer 119 material includes undoped silicon glass (USG).

[0106] Optionally, the sacrificial layer 119 material includes phosphate glass (PSG).

[0107] S405 , forming a protection layer on the substrate, wherein the protection layer covers the sacrificial layer, the piezoelectric portion and the second electrode.

[0108] In this embodiment, the protection provided by the protective layer 113 helps to improve the performance of the filter 100 and extend its service life.

[0109] Optionally, a protective layer 113 is deposited on the substrate 101, and the protective layer 113 covers the sacrificial layer 119, the piezoelectric portion 102 and the second electrode 111, and the end of the first electrode 110 away from the piezoelectric portion 102 is located inside the protective layer 113 or penetrates to the outside of the protective layer 113, so as to form a protective layer 113 on the substrate 101.

[0110] Optionally, the material of the protection layer 113 includes silicon dioxide.

[0111] Optionally, the material of the protection layer 113 includes silicon nitride.

[0112] S406 , forming a first pad and a second pad on the upper surface of the protective layer, and connecting the first pad to the first electrode, and connecting the second pad to the second electrode.

[0113] In this embodiment, a first pad 114 and a second pad 115 are formed on the upper surface of the protective layer 113, and the first pad 114 is connected to the first electrode 110, and the second pad 115 is connected to the second electrode 111, which can be used to establish an electrical connection between the filter 100 and the external structure for signal transmission.

[0114] S407 , removing the sacrificial layer to form a first cavity on the first side wall surface of the piezoelectric portion and a second cavity on the second side wall surface of the piezoelectric portion, thereby completing the manufacture of the filter.

[0115] In this embodiment, the sacrificial layer 119 is removed, and a first cavity 117 is formed on the first side wall surface 1021 side of the piezoelectric portion 102, that is, the protective layer 113, the first side wall surface 1021 of the piezoelectric portion 102 and the substrate 101 are enclosed to form the first cavity 117. A second cavity 118 is formed on the second side wall surface 1022 side of the piezoelectric portion 102, that is, the protective layer 113, the second side wall surface 1022 of the piezoelectric portion 102 and the substrate 101 are enclosed to form the second cavity 118, to achieve vibration performance.

[0116] It is understood that the method for removing the sacrificial layer 119 is not limited and can be selected according to needs. For example, a chemical solution is used to dissolve the sacrificial layer 119. For another example, the sacrificial layer 119 is removed by mechanical grinding or polishing.

[0117] In some embodiments, the steps of forming the first temperature compensation layer 107 on the first side wall surface 1021 and / or forming the second temperature compensation layer 108 on the second side wall surface 1022 include: Fig. 9 As shown, a temperature compensation layer 109 is deposited on the upper surface of the substrate 101 and the surface of the piezoelectric portion 102. Fig.10 As shown, the temperature compensation layer 109 is etched to obtain a first temperature compensation layer 107 of a first target size and / or a second temperature compensation layer 108 of a second target size.

[0118] In this embodiment, a first temperature compensation layer 107 of a first target size and / or a second temperature compensation layer 108 of a second target size are obtained by depositing a temperature compensation layer 109 on the upper surface of the substrate 101 and the surface of the piezoelectric part 102, and etching the temperature compensation layer 109, so as to form the first temperature compensation layer 107 on the first side wall surface 1021 and / or the second temperature compensation layer 108 on the second side wall surface 1022.

[0119] It can be understood that the first target size of the first temperature compensation layer 107 and the second target size of the second temperature compensation layer 108, for example, the thickness of the first temperature compensation layer 107, the thickness of the second temperature compensation layer 108, the size of the first temperature compensation layer 107 relative to the piezoelectric part 102, and the size of the second temperature compensation layer 108 relative to the piezoelectric part 102, can be designed as needed without limitation as long as the temperature drift can be reduced.

[0120] Exemplary: In the case where the filter 100 includes the first temperature compensation layer 107 and the second temperature compensation layer 108, etching the temperature compensation layer is achieved in the following manner: first, etching is performed to form the upper portions of the first temperature compensation layer 107 and the second temperature compensation layer 108, so that there is a third preset distance between the upper surface of the first temperature compensation layer 107 and the upper surface of the piezoelectric portion 102, and there is a fourth preset distance between the upper surface of the second temperature compensation layer 108 and the upper surface of the piezoelectric portion 102. Then, etching is performed to form the lower portions of the first temperature compensation layer 107 and the second temperature compensation layer 108, so that there is a fifth preset distance between the lower surface of the first temperature compensation layer 107 and the lower surface of the piezoelectric portion 102, and there is a sixth preset distance between the lower surface of the second temperature compensation layer 108 and the lower surface of the piezoelectric portion 102.

[0121] Combination Fig.17 and Fig.18As shown, in some embodiments, the lower portion of the first electrode is disposed on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, an end of the first electrode on a side away from the piezoelectric portion is located inside the protective layer, a first pad and a second pad are formed on the upper surface of the protective layer, and the first pad is connected to the first electrode, and the second pad is connected to the second electrode. The steps include: like Fig.17 As shown, a first filling hole 120 is formed in the protective layer 113 and the sacrificial layer 119 to expose the end of the first electrode 110 away from the piezoelectric part 102. A second filling hole 121 is formed in the protective layer 113 to expose the upper surface of the second electrode 111.

[0122] In this embodiment, the first filling hole 120 is formed in the protective layer 113 and the sacrificial layer 119. Specifically, the protective layer 113 and the sacrificial layer 119 are etched in a vertical direction in a region corresponding to the end of the first electrode 110 away from the piezoelectric portion 102 to form the first filling hole 120. The first filling hole 120 exposes the end of the first electrode 110 away from the piezoelectric portion 102, so that the end of the first electrode 110 away from the piezoelectric portion 102 is smoothly connected to the first pad 114.

[0123] In this embodiment, the second filling hole 121 is formed in the protective layer 113. Specifically, the region of the protective layer 113 corresponding to the upper surface of the second electrode 111 in the vertical direction is etched to form the second filling hole 121. The second filling hole 121 exposes the upper surface of the second electrode 111 so that the upper surface of the second electrode 111 is smoothly connected to the second pad 115.

[0124] like Fig.18 As shown, a metal layer 116 is formed in the first filling hole 120, and the metal layer 116 covers the upper surface of the protective layer 113 surrounding the first filling hole 120, so as to form a first pad 114, and the first pad 114 is connected to the first electrode 110. A metal layer 116 is formed in the second filling hole 121, and the metal layer 116 covers the upper surface of the protective layer 113 surrounding the second filling hole 121, so as to form a second pad 115, and the second pad 115 is connected to the second electrode 111.

[0125] In this embodiment, a metal layer 116 is formed in the first filling hole 120, that is, the metal layer 116 is filled in the first filling hole 120. In addition, the metal layer 116 filled in the first filling hole 120 can cover the upper surface of the protective layer 113 surrounding the first filling hole 120 to form a first pad 114, and the first pad 114 is connected to the first electrode 110. A metal layer 116 is formed in the second filling hole 121, that is, the metal layer 116 is filled in the second filling hole 121. In addition, the metal layer 116 filled in the second filling hole 121 can cover the upper surface of the protective layer 113 surrounding the second filling hole 121 to form a second pad 115, and the second pad 115 is connected to the second electrode 111.

[0126] In actual application, the metal layer 116 can be filled in the first filling hole 120 and the second filling hole 121 and the first pad 114 and the second pad 115 can be formed through a lift-off process or an etching process, thereby connecting the first pad 114 to the first electrode 110 and the second pad 115 to the second electrode 111.

[0127] Optionally, the material of the first pad 114 includes but is not limited to gold (Au), copper (Cu) and the like.

[0128] Optionally, the material of the second pad 115 includes but is not limited to gold (Au), copper (Cu) and the like.

[0129] Optionally, the material of the metal layer 116 includes but is not limited to gold (Au), copper (Cu) and the like.

[0130] like Figure 5 As shown, the embodiment of the present disclosure also provides a method for manufacturing a filter, which is used to manufacture the above-mentioned filter. The manufacturing method includes: S501, such as Figure 8 As shown, a piezoelectric portion is formed on the upper surface of the substrate, and the piezoelectric portion includes a first side wall surface and a second side wall surface arranged in opposite directions.

[0131] S502, such as Fig.10 As shown, a first temperature compensation layer is formed on the first side wall surface, and a second temperature compensation layer is formed on the second side wall surface.

[0132] S503, such as Fig.13 As shown, a first electrode is formed on the upper surface of the substrate and the first side wall surface of the piezoelectric portion so that the first electrode covers the first temperature compensation layer, and a second electrode is formed on the second side wall surface so that the second electrode covers the second temperature compensation layer.

[0133] S504, such as Fig.15As shown, a sacrificial layer is formed on the upper surface of the substrate, so that the upper surfaces of the sacrificial layer, the piezoelectric portion and the second electrode are flush, and the sacrificial layer covers the entire first electrode.

[0134] S505, such as Fig.16 As shown, a protection layer is formed on the substrate, the protection layer covers the sacrificial layer, the piezoelectric portion and the second electrode, and the end of the first electrode away from the piezoelectric portion is located inside the protection layer.

[0135] S506, such as Fig.17 As shown, a first filling hole is formed in the protective layer and the sacrificial layer, the first filling hole exposing the end of the first electrode away from the piezoelectric part; a second filling hole is formed in the protective layer, the second filling hole exposing the upper surface of the second electrode.

[0136] S507, such as Fig.18 As shown, a metal layer is formed in the first filling hole, and the metal layer covers the upper surface of the protective layer surrounding the first filling hole to form a first pad, and the first pad is connected to the first electrode; a metal layer is formed in the second filling hole, and the metal layer covers the upper surface of the protective layer surrounding the second filling hole to form a second pad, and the second pad is connected to the second electrode.

[0137] S508, such as Figure 1 As shown, the sacrificial layer is removed to form a first cavity on the first side wall surface of the piezoelectric portion, and a second cavity is formed on the second side wall surface of the piezoelectric portion, thereby completing the manufacture of the filter.

[0138] The filter 100 manufactured by the manufacturing method of this embodiment has a simple structure, can reduce temperature drift, improve reliability, enhance vibration performance, and can reduce the occupied area, so as to increase the number of packages during packaging and reduce manufacturing costs.

[0139] Combination Fig.21 and Fig. 22 As shown, in some embodiments, the lower portion of the first electrode is disposed on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, an end of the first electrode on a side away from the piezoelectric portion is penetrated to the outside of the protective layer, a first pad and a second pad are formed on the upper surface of the protective layer, and the first pad is connected to the first electrode, and the second pad is connected to the second electrode. The steps include: Combined Fig.21 As shown, a second filling hole 121 is formed in the protection layer 113 , and the second filling hole 121 exposes the upper surface of the second electrode 111 .

[0140] Combined Fig. 22As shown, a metal layer 116 is formed in a vertical direction at the end of the first electrode 110 away from the piezoelectric portion 102, and the metal layer 116 covers a portion of the upper surface of the protective layer 113 to form a first pad 114, and the first pad 114 is connected to the first electrode 110. A metal layer 116 is formed in the second filling hole 121, and the metal layer 116 covers the upper surface of the protective layer 113 surrounding the second filling hole 121 to form a second pad 115, and the second pad 115 is connected to the second electrode 111.

[0141] In this embodiment, the end of the first electrode 110 away from the piezoelectric portion 102 is extended to the outside of the protective layer 113 , so that the first electrode 110 can be connected to the first pad 114 outside the protective layer 113 .

[0142] In this embodiment, a metal layer 116 is formed in a vertical direction on the end of the first electrode 110 away from the piezoelectric portion 102, that is, a metal layer 116 is formed in a vertical direction on the end of the first electrode 110 located outside the protective layer 113, and the metal layer 116 covers a portion of the upper surface of the protective layer 113 to form a first pad 114, which can achieve connection between the first pad 114 and the first electrode 110 while reducing energy loss and improving structural stability.

[0143] In actual application, a lift-off process or an etching process can be used to form a metal layer 116 in the vertical direction of the end of the first electrode 110 away from the piezoelectric part 102, and the metal layer 116 covers a portion of the upper surface of the protective layer 113 to form a first pad 114, thereby achieving connection between the first pad 114 and the first electrode 110.

[0144] like Figure 6 As shown, the embodiment of the present disclosure further provides a method for manufacturing a filter, which is used to manufacture the filter 100 described above, and the manufacturing method includes: S601, such as Figure 8 As shown, a piezoelectric portion is formed on the upper surface of the substrate, and the piezoelectric portion includes a first side wall surface and a second side wall surface arranged in opposite directions.

[0145] S602, such as Fig.10 As shown, a first temperature compensation layer is formed on the first side wall surface, and a second temperature compensation layer is formed on the second side wall surface.

[0146] S603, such as Fig.13 As shown, a first electrode is formed on the upper surface of the substrate and the first side wall surface of the piezoelectric portion so that the first electrode covers the first temperature compensation layer, and a second electrode is formed on the second side wall surface so that the second electrode covers the second temperature compensation layer.

[0147] S604, such as Fig.19As shown, a sacrificial layer is formed on the upper surface of the substrate so that the upper surfaces of the sacrificial layer, the piezoelectric portion and the second electrode are flush with each other, and the sacrificial layer covers a portion of the first electrode.

[0148] S605, such as Fig. 20 As shown, a protection layer is formed on the substrate, the protection layer covers the sacrificial layer, the piezoelectric portion and the second electrode, and the end of the first electrode away from the piezoelectric portion is located outside the protection layer.

[0149] S606, such as Fig.21 As shown, a second filling hole is formed in the protection layer, and the second filling hole exposes the upper surface of the second electrode.

[0150] S607, such as Fig. 22 As shown, a metal layer is formed in the vertical direction of the end of the first electrode on the side away from the piezoelectric part, and the metal layer covers a portion of the upper surface of the protective layer to form a first pad, and the first pad is connected to the first electrode; a metal layer is formed in the second filling hole, and the metal layer covers the upper surface of the protective layer surrounding the second filling hole to form a second pad, and the second pad is connected to the second electrode.

[0151] S608, such as Figure 2 As shown, the sacrificial layer is removed to form a first cavity on the first side wall surface of the piezoelectric portion, and a second cavity is formed on the second side wall surface of the piezoelectric portion, thereby completing the manufacture of the filter.

[0152] The filter 100 manufactured by the manufacturing method of this embodiment has a simple structure, can reduce temperature drift, improve reliability, improve vibration performance, reduce energy loss, improve structural stability, and can reduce the occupied area, so as to increase the number of packages during packaging and reduce manufacturing costs.

[0153] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. The embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A filter, characterized in that: include: substrate; The piezoelectric part is arranged on the upper surface of the substrate, and includes a first side wall surface and a second side wall surface arranged in opposite directions; A first temperature compensation layer and / or a second temperature compensation layer, the first temperature compensation layer is arranged on a first side wall surface of the piezoelectric portion, and the second temperature compensation layer is arranged on a second side wall surface of the piezoelectric portion; A first electrode is disposed on a first side wall surface of the piezoelectric portion, and when the filter includes a first temperature compensation layer, the first electrode covers the first temperature compensation layer; A second electrode is disposed on a second side wall surface of the piezoelectric portion, and when the filter includes a second temperature compensation layer, the second electrode covers the second temperature compensation layer; The protective layer is disposed on the upper surface of the piezoelectric part and extends outward to respectively straddle the first electrode and the second electrode and then connect to the substrate, and forms a first cavity on the first side wall surface of the piezoelectric part and a second cavity on the second side wall surface of the piezoelectric part; The first pad and the second pad are both disposed on the upper surface of the protection layer and are connected to the first electrode and the second electrode in a one-to-one correspondence.

2. The filter according to claim 1, characterized in that The lower portion of the first electrode is disposed on the upper surface of the substrate and extends in a direction away from the piezoelectric portion. The end of the first electrode away from the piezoelectric portion is located inside the protective layer or penetrates outside the protective layer.

3. The filter according to claim 1, characterized in that The piezoelectric part is provided with one or more; When a plurality of piezoelectric portions are provided, the plurality of piezoelectric portions are spaced apart from each other, and a distance between two adjacent piezoelectric portions is greater than 1 μm.

4. The filter according to any one of claims 1 to 3, characterized in that In the vertical direction, there is a first preset distance between the upper surface of the first electrode and the upper surface of the piezoelectric portion, and the lower surface of the first electrode is flush with the lower surface of the piezoelectric portion; and / or, In the vertical direction, the upper surface of the second electrode is flush with the upper surface of the piezoelectric portion, and a second preset interval is present between the lower surface of the second electrode and the lower surface of the piezoelectric portion.

5. The filter according to any one of claims 1 to 3, characterized in that In the vertical direction, there is a third preset distance between the upper surface of the first temperature compensation layer and the upper surface of the piezoelectric portion; and / or, there is a fourth preset distance between the upper surface of the second temperature compensation layer and the upper surface of the piezoelectric portion; and / or, there is a fifth preset distance between the lower surface of the first temperature compensation layer and the lower surface of the piezoelectric portion; and / or, there is a sixth preset distance between the lower surface of the second temperature compensation layer and the lower surface of the piezoelectric portion; In a direction perpendicular to the first side wall surface or the second side wall surface of the piezoelectric portion, the thickness of the first temperature compensation layer is the first thickness, and / or the thickness of the second temperature compensation layer is the second thickness.

6. The filter according to any one of claims 1 to 3, characterized in that: The angle between the first side wall surface of the piezoelectric portion and the upper surface of the substrate is 85° to 90°; and / or, An included angle between the second side wall surface of the piezoelectric portion and the upper surface of the substrate is 85° to 90°.

7. A method for manufacturing a filter, used for manufacturing the filter according to any one of claims 1 to 6, characterized in that: The manufacturing method includes: forming a piezoelectric portion on the upper surface of the substrate, wherein the piezoelectric portion includes a first side wall surface and a second side wall surface disposed opposite to each other; forming a first temperature compensation layer on the first side wall surface, and / or forming a second temperature compensation layer on the second side wall surface; A first electrode is formed on a first side wall surface of the piezoelectric portion, and when the filter includes a first temperature compensation layer, the first electrode covers the first temperature compensation layer; a second electrode is formed on a second side wall surface of the piezoelectric portion, and when the filter includes a second temperature compensation layer, the second electrode covers the second temperature compensation layer; forming a sacrificial layer on the upper surface of the substrate, so that the upper surfaces of the sacrificial layer, the piezoelectric portion and the second electrode are flush, and the sacrificial layer covers the first electrode; forming a protective layer on the substrate, the protective layer covering the sacrificial layer, the piezoelectric portion and the second electrode; Forming a first pad and a second pad on the upper surface of the protective layer, and connecting the first pad to the first electrode and the second pad to the second electrode; The sacrificial layer is removed to form a first cavity on the first side wall surface of the piezoelectric portion and a second cavity on the second side wall surface of the piezoelectric portion.

8. The manufacturing method according to claim 7, characterized in that: The step of forming a first temperature compensation layer on the first side wall surface and / or forming a second temperature compensation layer on the second side wall surface comprises: Depositing a temperature compensation layer on the upper surface of the substrate and the surface of the piezoelectric portion; The temperature compensation layer is etched to obtain a first temperature compensation layer of a first target size and / or a second temperature compensation layer of a second target size.

9. The manufacturing method according to claim 7 or 8, characterized in that: The lower portion of the first electrode is disposed on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, an end portion of the first electrode away from the piezoelectric portion is located inside the protective layer, a first pad and a second pad are formed on the upper surface of the protective layer, and the first pad is connected to the first electrode, and the second pad is connected to the second electrode, comprising: A first filling hole is formed in the protective layer and the sacrificial layer, the first filling hole exposing an end of the first electrode away from the piezoelectric portion; a second filling hole is formed in the protective layer, the second filling hole exposing an upper surface of the second electrode; A metal layer is formed in the first filling hole, and the metal layer covers the upper surface of the protective layer surrounding the first filling hole to form a first pad, and the first pad is connected to the first electrode; a metal layer is formed in the second filling hole, and the metal layer covers the upper surface of the protective layer surrounding the second filling hole to form a second pad, and the second pad is connected to the second electrode.

10. The manufacturing method according to claim 7 or 8, characterized in that: The lower portion of the first electrode is disposed on the upper surface of the substrate and extends in a direction away from the piezoelectric portion, an end portion of the first electrode on a side away from the piezoelectric portion is penetrated to the outside of the protective layer, a first pad and a second pad are formed on the upper surface of the protective layer, and the first pad is connected to the first electrode, and the second pad is connected to the second electrode. The steps include: forming a second filling hole in the protective layer, wherein the second filling hole exposes an upper surface of the second electrode; A metal layer is formed in the vertical direction of the end of the first electrode on the side away from the piezoelectric part, and the metal layer covers a portion of the upper surface of the protective layer to form a first pad, and the first pad is connected to the first electrode; a metal layer is formed in the second filling hole, and the metal layer covers the upper surface of the protective layer surrounding the second filling hole to form a second pad, and the second pad is connected to the second electrode.

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