Resonator manufacturing method and resonator

Abstract

The present invention discloses a method for manufacturing a resonator and a resonator, wherein the manufacturing method comprises: sequentially stacking a first electrode layer, a piezoelectric layer, and a second electrode layer. A support layer is manufactured on the surface of the second electrode layer on the side away from the piezoelectric layer, the support layer comprising a plurality of first protrusions arranged at intervals, and a first recessed portion is formed between adjacent first protrusions. A cutoff boundary layer is manufactured to cover the surface of the first protrusion on the side away from the piezoelectric layer and the wall surface of the first recessed portion. A plurality of second notches penetrating the first electrode layer are manufactured on the first electrode layer, and the second notches divide the first electrode layer into a plurality of first electrodes. A plurality of grooves penetrating the piezoelectric layer are manufactured on the piezoelectric layer, and the plurality of grooves divide the piezoelectric layer into a plurality of piezoelectric bodies, and the second electrode is exposed in the grooves; a barrier layer is manufactured, and the barrier layer at least covers the bottom of each groove; and at least two first protrusions are removed so that the second electrode and the cutoff boundary layer form at least two cavities.

Description

Technical Field

[0001] The present invention relates to the technical field related to resonators, and in particular to a method for manufacturing a resonator and the resonator. Background Art

[0002] As a physical device that can produce resonance, resonators are widely used in many fields, such as wireless communications, audio, home appliances and consumer electronics, and automotive electronics.

[0003] The current traditional resonator structure includes other functional film layers such as the top electrode, piezoelectric layer, bottom electrode and cutoff boundary layer. The existing conventional piezoelectric layer is formed on the entire surface, which will cause the overall stress of the body resonator to be too large. In the subsequent processes (such as the release process, cutting process, etc.), stress mismatch is easy to occur, which may cause problems such as film shedding, delamination, and unstable resonator performance.

[0004] Therefore, how to solve the stress mismatch problem of the piezoelectric layer in subsequent processes is an urgent problem to be solved. Summary of the invention

[0005] The present invention provides a method for manufacturing a resonator and a resonator, which can solve the problem of stress mismatch of a piezoelectric layer in subsequent processes.

[0006] In a first aspect, an embodiment of the present application provides a method for manufacturing a resonator. Specifically, the method includes:

[0007] The first electrode layer, the piezoelectric layer, and the second electrode layer are sequentially stacked;

[0008] A plurality of first notches penetrating the second electrode layer are formed on the second electrode layer, wherein the plurality of first notches divide the second electrode layer into a plurality of second electrodes, and a portion of the surface of the piezoelectric layer is exposed in the first notches;

[0009] A support layer is formed on a surface of the second electrode layer on a side away from the piezoelectric layer, wherein the support layer comprises a plurality of first convex blocks arranged at intervals, and first recessed portions are formed between adjacent first convex blocks;

[0010] Making a cut-off boundary layer, wherein the cut-off boundary layer covers a surface of the first protrusion away from the piezoelectric layer and a wall surface of the first recessed portion;

[0011] A plurality of second notches are formed on the first electrode layer, the plurality of second notches divide the first electrode layer into a plurality of first electrodes, and a surface of the piezoelectric layer on one side away from the second electrode layer is exposed in the second notches;

[0012] A plurality of grooves penetrating the piezoelectric layer are formed on the piezoelectric layer, wherein the plurality of grooves divide the piezoelectric layer into a plurality of piezoelectric bodies, and the second electrode is exposed in the grooves;

[0013] Making a barrier layer, wherein the barrier layer at least covers the bottom of each of the grooves;

[0014] At least two first bumps are removed so that the second electrode and the cut-off boundary layer form at least two cavities.

[0015] In a possible implementation of the first aspect, the sequentially stacking of the first electrode layer, the piezoelectric layer, and the second electrode layer includes:

[0016] A first substrate is provided, and the first electrode layer, the piezoelectric layer, and the second electrode layer are sequentially stacked on a surface of one side of the first substrate.

[0017] In a possible implementation of the first aspect, the second electrode includes a first bottom electrode and a second bottom electrode, the length of the first bottom electrode is greater than that of the second bottom electrode, the first protrusion includes a first protrusion and a second protrusion, the first protrusion covers a portion of the first bottom electrode, the second protrusion covers the second bottom electrode, the first bottom electrode is exposed in a first recessed portion between two adjacent first protrusions, and the piezoelectric layer is exposed in a first recessed portion between two adjacent first protrusions and the second protrusion.

[0018] In a possible implementation of the first aspect, removing at least two first bumps so that the second electrode and the cut-off boundary layer form at least two cavities includes:

[0019] There is a gap between the first bottom electrode and the cut-off boundary layer;

[0020] A through hole is provided on part of the piezoelectric body, and the through hole and the gap together form an injection port, and the etching liquid is injected through the injection port to corrode the first protruding part to form the cavity.

[0021] In a possible implementation of the first aspect, before manufacturing the first electrode, the manufacturing method further includes:

[0022] Depositing a bonding layer on the cut-off boundary layer, wherein the bonding layer covers a surface of the cut-off boundary layer that is away from the piezoelectric layer and fills the first recessed portion;

[0023] A second substrate is provided, the second substrate is bonded to a surface of the bonding layer facing away from the piezoelectric layer, and the first substrate is removed.

[0024] In a possible implementation of the first aspect, the manufacturing of the barrier layer, wherein the barrier layer at least covers the bottom of each of the grooves, includes: the barrier layer includes a barrier body and a metal body;

[0025] The blocking body (1081) covers the wall and bottom of the groove between two adjacent piezoelectric bodies and extends to the surface of the piezoelectric body on one side facing away from the second substrate;

[0026] The metal body covers a portion of the surface of the first electrode on a side facing away from the second electrode layer.

[0027] In a possible implementation of the first aspect, the first electrode includes a first top electrode and a second top electrode arranged at intervals in a first direction, the first top electrode and the second top electrode correspond to different cavities; the first top electrode has a first side facing away from the second top electrode, and the second top electrode has a second side facing away from the first top electrode;

[0028] The orthographic projection of the first side portion on the cut-off boundary layer is located in the cavity corresponding to the first top electrode, and the orthographic projection of the second side portion on the cut-off boundary layer is located in the cavity corresponding to the second top electrode.

[0029] In a possible implementation of the first aspect, the width of the groove is greater than 5 μm.

[0030] In a second aspect, the present application further provides a resonator, the resonator comprising: a first electrode layer, a piezoelectric layer, and a second electrode layer which are stacked;

[0031] The first electrode layer is provided with a plurality of second notches penetrating the first electrode layer to form a plurality of first electrodes spaced apart from each other; the second electrode layer is provided with a plurality of first notches penetrating the second electrode layer to form a plurality of second electrodes spaced apart from each other; a surface of the piezoelectric layer facing away from the first electrode layer is exposed at the first notches; a surface of the piezoelectric layer facing away from the second electrode layer is exposed at the second notches;

[0032] The piezoelectric layer is provided with a plurality of grooves penetrating the piezoelectric layer to form a plurality of piezoelectric bodies arranged at intervals, the second electrode is exposed in the grooves, and a barrier layer is also provided on the piezoelectric layer, the barrier layer at least covers the bottom of each of the grooves;

[0033] A support layer is further provided on the surface of the second electrode layer facing away from the piezoelectric layer, and the support layer includes a plurality of first bumps arranged at intervals, and a first recessed portion is formed between adjacent first bumps. A surface of the first bump facing away from the piezoelectric layer and a wall of the first recessed portion are covered with a cutoff boundary layer. After the cutoff boundary layer is formed, at least two first bumps are removed to form at least two cavities between the cutoff boundary layer and the second electrode.

[0034] In a possible implementation of the second aspect, the resonator further includes a second substrate, the second substrate is connected to the cut-off boundary layer via a bonding layer, and the bonding layer is filled in the first recessed portion.

[0035] In a possible implementation of the second aspect, the first electrode includes a first top electrode and a second top electrode arranged at intervals in a first direction, and the first top electrode and the second top electrode correspond to different cavities;

[0036] Among them, the first top electrode has a first side portion facing away from the second top electrode, the second top electrode has a second side portion facing away from the first top electrode, the orthographic projection of the first side portion on the cutoff boundary layer is located in the cavity corresponding to the first top electrode, and the orthographic projection of the second side portion on the cutoff boundary layer is located in the cavity corresponding to the second top electrode.

[0037] In a possible implementation of the second aspect, the second electrode includes a first bottom electrode and a second bottom electrode, and the length of the first bottom electrode is greater than that of the second bottom electrode;

[0038] The first convex block includes a first convex portion and a second convex portion, the first convex portion covers a portion of the first bottom electrode, the second convex portion covers the second bottom electrode, the first bottom electrode is exposed in a first concave portion between two adjacent first convex portions, and the piezoelectric layer is exposed in a first concave portion between the adjacent first convex portion and the second convex portion;

[0039] After the cut-off boundary layer is formed, at least two first protrusions are removed, so that a cavity is formed between the at least two first bottom electrodes and the cut-off boundary layer.

[0040] In a possible implementation of the second aspect, the blocking layer includes a blocking body and a metal body, the blocking body covers the wall and bottom of the groove between two adjacent piezoelectric bodies and extends to the surface of the piezoelectric body facing away from the second electrode layer, and the metal body is connected to the surface of the first electrode facing away from the second electrode layer.

[0041] In a possible implementation of the second aspect, a width of the groove is greater than 5 μm.

[0042] One of the above technical solutions has the following advantages or beneficial effects: Based on the resonator manufacturing method provided in the application, the resonator manufactured is no longer released in a concentrated manner during the subsequent process when the piezoelectric layer is released from stress, thereby avoiding problems such as film shedding, stratification, and unstable resonator performance caused by stress mismatch. At the same time, the blocking body and part of the second electrode together constitute a blocking structure, which together play a blocking role to prevent the formation of a leakage channel between the piezoelectric layer and the support layer during the release process, causing the Release leakage to etch the support layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 is a flow chart of a method for manufacturing a resonator provided in an embodiment of the present application;

[0045] Figure 2 is a schematic diagram of a structure of constructing a sandwich structure on a first substrate provided by an embodiment of the present invention;

[0046] Figure 3 is a schematic diagram of a structure for manufacturing a second electrode provided by an embodiment of the present invention;

[0047] Figure 4 is a schematic diagram of a structure for manufacturing a support layer on a second electrode layer provided by an embodiment of the present invention;

[0048] Figure 5 is a schematic diagram of a structure for making a cut-off boundary layer provided by an embodiment of the present invention;

[0049] Figure 6 is a schematic diagram of the structure of manufacturing a bonding layer provided by an embodiment of the present invention;

[0050] Figure 7 is a schematic structural diagram of bonding a second substrate and a bonding layer provided by an embodiment of the present invention;

[0051] Figure 8 is a schematic diagram of a structure in which a first substrate is removed according to an embodiment of the present invention;

[0052] Fig. 9 is a schematic diagram of a structure for manufacturing a first electrode provided by an embodiment of the present invention;

[0053] Fig.10It is a schematic diagram of the structure of manufacturing a piezoelectric body provided by an embodiment of the present invention;

[0054] Fig.11 is a schematic diagram of a structure for forming a barrier body and a metal body provided by an embodiment of the present invention;

[0055] Fig.12 is a top view of a barrier and a metal body provided by an embodiment of the present invention;

[0056] Fig.13 It is a schematic diagram of a structure in which a cavity is formed after a part of the supporting layer is corroded according to an embodiment of the present invention.

[0057] The main reference numerals in the drawings of this application specification are described as follows:

[0058] 100. a first substrate;

[0059] 101, first electrode layer; 1011, first electrode; 10111, first top electrode; 10112, second top electrode; 1012, second gap;

[0060] 102, piezoelectric layer; 1021, piezoelectric body; 1022, groove;

[0061] 103, second electrode layer; 1031, second electrode; 10311, first bottom electrode; 10312, second bottom electrode; 1032, first gap;

[0062] 104, support layer; 1041, first convex block; 10411, first protruding portion; 10412, second protruding portion; 1042, first concave portion;

[0063] 105, cut-off boundary layer; 1051, second convex block; 1052, second concave portion;

[0064] 106, bonding layer; 1061, third bump; 1062, third recess;

[0065] 107. A second substrate;

[0066] 108, barrier layer; 1081, barrier body; 1082, metal body;

[0067] 200, cavity;

[0068] 300, injection port;

[0069] 10. First side portion; 11. Second side portion. DETAILED DESCRIPTION

[0070] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0071] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0072] 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0073] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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, a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0074] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0075] As mentioned above, the piezoelectric layers in existing resonators are formed on the entire surface, which will cause the overall stress of the body resonator to be too large, and it is easy to cause stress mismatch in subsequent processes (such as Release process, cutting process, etc.), which may cause problems such as film shedding, delamination, and unstable resonator performance. In order to solve the above problems, the present application provides a method for manufacturing a resonator and a resonator, which can solve the problems caused by stress mismatch of the piezoelectric layer in subsequent processes. Below, the technical solution of the present application is described in detail. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments of the present application. In the following embodiments, the description of each embodiment has its own emphasis. For the parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0076] Figure 1 According to an embodiment of the present application, a method for manufacturing a resonator is shown, comprising:

[0077] S101: stacking a first electrode layer, a piezoelectric layer and a second electrode layer in sequence.

[0078] S102: making a plurality of first notches penetrating the second electrode layer, wherein the plurality of first notches divide the second electrode layer into a plurality of second electrodes, and a portion of the surface of the piezoelectric layer is exposed in the first notches.

[0079] S103: manufacturing a support layer on a surface of the second electrode layer facing away from the piezoelectric layer, wherein the support layer comprises a plurality of first protrusions arranged at intervals, and first recessed portions are formed between adjacent first protrusions.

[0080] S104: manufacturing a cut-off boundary layer, wherein the cut-off boundary layer covers a surface of the first protrusion away from the piezoelectric layer and a wall surface of the first recessed portion.

[0081] S105: making a plurality of second notches penetrating the first electrode layer, the plurality of second notches dividing the first electrode layer into a plurality of first electrodes, and a surface of the piezoelectric layer on one side away from the second electrode layer is exposed in the second notches.

[0082] S106: making a plurality of grooves penetrating the piezoelectric layer, wherein the plurality of grooves divide the piezoelectric layer into a plurality of piezoelectric bodies, and the second electrode is exposed in the grooves.

[0083] S107: Making a barrier layer, wherein the barrier layer at least covers the bottom of each groove.

[0084] S108: removing at least two first bumps, so that the second electrode and the cut-off boundary layer form at least two cavities.

[0085] In step S101, the first electrode layer 101, the piezoelectric layer 102, and the second electrode layer 103 can be made by providing a first substrate 100 as a support, and the first electrode layer 101, the piezoelectric layer 102, and the second electrode layer 103 are sequentially made from bottom to top on one side surface of the first substrate 100 to form a sandwich structure. The first electrode layer 101, the piezoelectric layer 102, and the second electrode layer 103 are all made by deposition. The material of the first electrode layer 101 and the second electrode layer 103 can be one of molybdenum or tungsten or a mixture of the two. The deposited material of the piezoelectric layer 102 is one of polycrystalline or single crystal or a mixture of polycrystalline and single crystal aluminum nitride, aluminum nitride scandium, quartz, etc., or a combination of at least two materials. These materials have a piezoelectric effect, that is, when pressure or an electric field is applied, charge separation or mechanical deformation will occur, thereby realizing the piezoelectric effect. Different piezoelectric materials have different properties and characteristics. In practical applications, suitable materials can be selected according to specific application requirements for deposition of the first electrode layer 101, the piezoelectric layer 102, and the second electrode layer 103. Figure 2 shown.

[0086] In step 102, a plurality of first notches 1032 penetrating the second electrode layer 103 are formed on the second electrode layer 103. The plurality of first notches 1032 divide the second electrode layer 103 into a plurality of second electrodes 1031, and a portion of the surface of the piezoelectric layer 102 is exposed in the first notches 1032. Figure 3 After etching the second electrode layer 103, the second electrode layer 103 that was originally horizontally laid on the piezoelectric layer 102 is etched into a plurality of second electrodes 1031. It should be understood that when etching the second electrode layer 103, the number of second electrodes 1031 can be etched according to actual needs. Among them, the second electrode 1031 includes a first bottom electrode 10311 and a second bottom electrode 10312, and the length of the first bottom electrode 10311 is greater than that of the second bottom electrode 10312. In the embodiment of the present application, two first bottom electrodes 10311 are provided, and two second bottom electrodes 10312 are provided, and the two second bottom electrodes 10312 are arranged between the two first bottom electrodes 10311 at intervals.

[0087] In step S103, a support layer 104 is formed on the surface of the second electrode layer 103 facing away from the piezoelectric layer 102. The support layer 104 includes a plurality of first bumps 1041 arranged at intervals, and a first recess 1042 is formed between adjacent first bumps 1041. The support layer 104 is formed on the second electrode 1031 by deposition, and the material of the support layer 104 is one of silicon (Si), phosphorus (P), and the like. Figure 4, by first depositing a support layer 104 of a preset thickness, the support layer 104 of the preset thickness covers each second electrode 1031, and then etching the support layer 104, so that a plurality of first recessed portions 1042 are formed on the support layer 104, and a first convex block 1041 is formed between two adjacent first recessed portions 1042. Further, in some embodiments, the first convex block 1041 includes a first protruding portion 10411 and a second protruding portion 10412, the first protruding portion 10411 covers a portion of the first bottom electrode 10311, and the second protruding portion 10412 covers the second bottom electrode 10312. The first bottom electrode 10311 is exposed in the first recessed portion 1042 between two adjacent first protruding portions 10411, and the piezoelectric layer 102 is exposed in the first recessed portion 1042 between the adjacent first protruding portions 10411 and the second protruding portions 10412.

[0088] In step S104, a cut-off boundary layer 105 is formed, and the cut-off boundary layer 105 is located on a side surface of the support layer 104 away from the first substrate 100. Specifically, the cut-off boundary layer 105 is formed by deposition on a side surface of the support layer 104 away from the first substrate 100, and the cut-off boundary layer 105 is etched so that the cut-off boundary layer 105 covers a side surface of the first bump 1041 away from the piezoelectric layer 102 and a wall surface of the first recessed portion 1042. Figure 5 The cut-off boundary layer 105 completely adheres to a side of the support layer 104 having a plurality of first bumps 1041, and a plurality of second bumps 1051 are formed based on the edges of the plurality of first bumps 1041, and a plurality of second recesses 1052 are formed based on the edges of the plurality of first recesses 1042. The material of the cut-off boundary layer 105 may be polysilicon.

[0089] Before manufacturing the first electrode 1011 in step S105, a bonding layer 106 needs to be manufactured. The bonding layer 106 may be manufactured by deposition. The material of the bonding layer 106 may be one of undoped silicate glass materials, phosphosilicate glass, silicon nitride, etc., or a mixture of at least two of them. Figure 6 , a side of the bonding layer 106 close to the cut-off boundary layer 105 is formed with a plurality of third bumps 1061 to fill the first recess 1042 (or the second recess 1052), and a plurality of third recesses 1062 are formed to fit the second bumps 1051. Further, the side away from the cut-off boundary layer 105 is ground, preferably by chemical mechanical polishing (CMP), so that the side away from the cut-off boundary layer 105 is flat and uniform. Furthermore, a second substrate 107 is provided to bond the second substrate 107 to the bonding layer 106. The product is then rotated and inverted, so that the second substrate 107 is used as the base, and the first substrate 100 is removed at the same time. For details, please refer to Figures 7 and 8.

[0090] Continue to refer Fig. 9 , step S105 makes a plurality of second notches 1012 on the first electrode layer 101, the plurality of second notches 1012 divide the first electrode layer 101 into a plurality of first electrodes 1011, and the surface of one side of the piezoelectric layer 102 away from the second electrode layer 103 is exposed in the second notch 1012. The first electrode 1011 includes a first top electrode 10111 and a second top electrode 10112 arranged at intervals in the first direction, and the first top electrode 10111 and the second top electrode 10112 correspond to different cavities 200. The first top electrode 10111 has a first side portion 10 facing away from the second top electrode 10112, and the second top electrode 10112 has a second side portion 11 facing away from the first top electrode 10111. The orthographic projection of the first side portion 10 on the cutoff boundary layer 105 is located in the cavity 200 corresponding to the first top electrode 10111. The orthographic projection of the second side portion 11 on the cutoff boundary layer 105 is located in the cavity 200 corresponding to the second top electrode 10112. In other words, in the first direction, the position of the right side of the first top electrode 10111 does not exceed the position of the first side portion 10, and the position of the left side of the second top electrode 10112 does not exceed the position of the second side wall 13. The first electrode 1011 and the second electrode 1031 are electrically connected to the piezoelectric layer 102 to form a piezoelectric sensing structure.

[0091] In step S106, the piezoelectric layer 102 is etched to form a plurality of grooves 1022 penetrating the piezoelectric layer 102. The plurality of grooves 1022 divide the piezoelectric layer 102 into a plurality of piezoelectric bodies 1021, and the second electrode 1031 is exposed in the grooves 1022. Fig.10 The grooves 1022 and the second electrodes 1031 correspond one to one, the orthographic projections of the corresponding grooves 1022 and the second electrodes 1031 overlap, and the width of the grooves 1022 is greater than 5 μm. In other words, the distance between adjacent piezoelectric bodies 1021 is greater than 5 μm.

[0092] In step S107, a barrier layer 108 is fabricated. The barrier layer 108 may be fabricated by deposition, wherein the barrier layer 108 is made of a metal material. Fig.11 , the barrier layer 108 is etched to form a barrier 1081 covering the bottom of the groove 1022 and a metal body 1082 attached to the first electrode 1011. Among them, multiple barrier bodies 1081 and the second electrode 1031 constitute the barrier layer 108, which together play a blocking role to prevent the formation of a leakage channel between the piezoelectric layer 102 and the support layer 104 during the release process, causing the Release leakage to corrode the support layer 104. The metal body 1082 is used to achieve electrical connection with other components. Continue to refer to Fig.12, the above-mentioned multiple piezoelectric bodies 1021 are arranged at intervals from each other. It should be understood that the blocking body 1081 covers the side wall and bottom of the groove 1022 between two adjacent piezoelectric bodies 1021 and extends to the side surface of the piezoelectric body 1021 away from the second substrate 107. Among them, the side surface of the piezoelectric body 1021 away from the second substrate 107 is not completely covered by the blocking body 1081. It can be understood that the number of the above-mentioned piezoelectric bodies 1021 is determined according to the wafer size parameters of the product. Fig.12 The relative positions of the piezoelectric body 1021 and the blocking body 1081 are merely exemplified, and the number and shape of the piezoelectric body 1021 are not limited.

[0093] In step 108, a portion of the support layer 104 is etched to form the cavity 200 required for the resonator. When etching the portion of the support layer 104, a corresponding etching liquid needs to be selected according to the material of the support layer 104. In other words, the etching liquid must selectively etch the portion of the support layer 104 during the release process, and must remain relatively inert to the materials of other structures. Fig.12 and Fig.13 The above-mentioned part of the support layer 104 can be, for example, the first protrusion 10411. The first protrusion 10411 is etched through the injection port 300 to form the cavity 200 required for the resonator between the second electrode 1031 and the cut-off boundary layer 105. The above-mentioned injection port 300 is composed of the gap between the first bottom electrode 10311 and the side wall of the cut-off boundary layer 105 and the through hole set on the piezoelectric body 1021. Fig.13 The cross-sectional view shown does not cut through the through hole. It should be understood that Fig.12 and Fig.13 The position and number of the injection ports 300 in the embodiment are only for illustration and are not intended to limit the position and number of the injection ports 300 provided in the present application. The second protrusion 10412 is not subjected to corrosion treatment. The second protrusion 10412 and the corresponding cut-off boundary layer 105 form a support structure and play a supporting role together to disperse the stress generated when the resonator is under pressure, thereby solving the problem of excessive stress in a single support.

[0094] The method for manufacturing a resonator provided in this embodiment can be used to manufacture an acoustic wave resonator or a surface acoustic wave resonator.

[0095] It is understandable. Based on the resonator manufacturing method provided in the application, the resonator manufactured will no longer release the stress in a concentrated manner during the subsequent process when the piezoelectric layer 102 is released, thereby avoiding problems such as film shedding, stratification, and unstable resonator performance caused by stress mismatch. At the same time, the blocking body 1081 and part of the second electrode 1031 together constitute a blocking structure, which together play a blocking role to prevent the formation of a leakage channel between the piezoelectric layer 102 and the support layer 104 during the release process, causing the Release leakage to etch the support layer 104.

[0096] The embodiment of the present application also discloses a resonator, which includes a first electrode layer 101, a piezoelectric layer 102, and a second electrode layer 103 that are stacked. The first electrode layer 101 is provided with a plurality of second notches 1012 that penetrate through itself to form a plurality of first electrodes 1011 that are spaced apart. The second electrode layer 103 is provided with a plurality of first notches 1032 that penetrate through itself to form a plurality of second electrodes 1031 that are spaced apart. The surface of the piezoelectric layer 102 that faces away from the first electrode layer 101 is exposed at the first notches 1032, and the surface of the piezoelectric layer 102 that faces away from the second electrode layer 103 is exposed at the second notches 1012. The piezoelectric layer 102 is provided with a plurality of grooves 1022 that penetrate through itself to form a plurality of piezoelectric bodies 1021 that are spaced apart. The second electrodes 1031 are exposed in the grooves 1022. A barrier layer 108 is also provided on the piezoelectric layer 102, and the barrier layer 108 at least covers the bottom of each groove 1022. Among them, a support layer 104 is also provided on the side surface of the second electrode layer 103 facing away from the piezoelectric layer 102, and the support layer 104 includes a plurality of first bumps 1041 arranged at intervals, and a first recess 1042 is formed between adjacent first bumps 1041. The side surface of the first bump 1041 facing away from the piezoelectric layer 102 and the wall surface of the first recess 1042 are covered with a cutoff boundary layer 105. After the cutoff boundary layer 105 is formed, at least two first bumps 1041 are removed to form at least two cavities 200 between the cutoff boundary layer 105 and the second electrode 1031.

[0097] In some embodiments, the resonator further includes a second substrate 107 , the second substrate 107 is connected to the cut-off boundary layer 105 via a bonding layer 106 , and the bonding layer 106 is filled in the first recess 1042 .

[0098] In some embodiments, the first electrode 1011 includes a first top electrode 10111 and a second top electrode 10112 arranged at intervals in a first direction, and the first top electrode 10111 and the second top electrode 10112 correspond to different cavities 200. The first top electrode 10111 has a first side portion 10 facing away from the second top electrode 10112, and the second top electrode 10112 has a second side portion 11 facing away from the first top electrode 10111. The orthographic projection of the first side portion 10 on the cutoff boundary layer 105 is located in the cavity 200 corresponding to the first top electrode 10111, and the orthographic projection of the second side portion 11 on the cutoff boundary layer 105 is located in the cavity 200 corresponding to the second top electrode 10112. In some embodiments, the second electrode 1031 includes a first bottom electrode 10311 and a second bottom electrode 10312, and the length of the first bottom electrode 10311 is greater than that of the second bottom electrode 10312. The first bump 1041 includes a first protrusion 10411 and a second protrusion 10412. The first protrusion 10411 covers a portion of the first bottom electrode 10311, and the second protrusion 10412 covers the second bottom electrode 10312. The first bottom electrode 10311 is exposed in a first recess 1042 between two adjacent first protrusions 10411, and the piezoelectric layer 102 is exposed in a first recess 1042 between the adjacent first protrusions 10411 and the second protrusion 10412. After the cutoff boundary layer 105 is formed, at least two first protrusions 10411 are removed, so that a cavity 200 is formed between the at least two first bottom electrodes 10311 and the cutoff boundary layer 105.

[0099] In some embodiments, the barrier layer 108 includes a barrier 1081 and a metal body 1082, the barrier 1081 covers the wall and bottom of the groove 1022 between two adjacent piezoelectric bodies 1021, and extends to the surface of the piezoelectric body 1021 on the side away from the second electrode layer 103, and the metal body 1082 is connected to the surface of the first electrode 1011 on the side away from the second electrode layer 103. It should be noted that in some embodiments, the width of the groove 1022 is greater than 5 μm.

[0100] Therefore, the resonator disclosed in the present application is manufactured by the manufacturing method of the resonator disclosed above, and the overall structure is a lateral sandwich structure. When making the cavity 200, the supporting layer 104 can be directly corroded without bonding another wafer to make the cavity 200, thereby reducing the complexity of the processing technology of the resonator.

[0101] It should be noted that, for the sake of convenience of description, the aforementioned method embodiments are all expressed as a series of action combinations, but those skilled in the art should know that the content of the present invention is not limited to the described order of actions, because according to the content of the present invention, certain steps can be performed in other orders or simultaneously.

[0102] In summary, although the present application has been disclosed as above with preferred embodiments, the above preferred embodiments are not intended to limit the contents of the present invention. Ordinary technicians in this field can make various changes and modifications without departing from the spirit and scope of the contents of the present invention. Therefore, the scope of protection of the contents of the present invention shall be based on the scope defined in the claims.

Claims

1. A method for manufacturing a resonator, characterized in that: include: The first electrode layer, the piezoelectric layer, and the second electrode layer are sequentially stacked; A plurality of first notches penetrating the second electrode layer are formed on the second electrode layer, wherein the plurality of first notches divide the second electrode layer into a plurality of second electrodes, and a portion of the surface of the piezoelectric layer is exposed in the first notches; A support layer is formed on a surface of the second electrode layer on a side away from the piezoelectric layer, wherein the support layer comprises a plurality of first convex blocks arranged at intervals, and first recessed portions are formed between adjacent first convex blocks; Making a cut-off boundary layer, wherein the cut-off boundary layer covers a surface of the first protrusion away from the piezoelectric layer and a wall surface of the first recessed portion; A plurality of second notches are formed on the first electrode layer, the plurality of second notches divide the first electrode layer into a plurality of first electrodes, and a surface of the piezoelectric layer on one side away from the second electrode layer is exposed in the second notches; A plurality of grooves penetrating the piezoelectric layer are formed on the piezoelectric layer, wherein the plurality of grooves divide the piezoelectric layer into a plurality of piezoelectric bodies, and the second electrode is exposed in the grooves; Making a barrier layer, the barrier layer at least covers the bottom of each groove, the barrier layer comprising a barrier body and a metal body; At least two first bumps are removed so that the second electrode and the cut-off boundary layer form at least two cavities.

2. The method for manufacturing a resonator according to claim 1, characterized in that: The method of sequentially stacking the first electrode layer, the piezoelectric layer, and the second electrode layer comprises: A first substrate is provided, and the first electrode layer, the piezoelectric layer, and the second electrode layer are sequentially stacked on a surface of one side of the first substrate.

3. The method for manufacturing a resonator according to claim 1, characterized in that: The second electrode includes a first bottom electrode and a second bottom electrode, the length of the first bottom electrode is greater than that of the second bottom electrode, the first protrusion includes a first protrusion and a second protrusion, the first protrusion covers a portion of the first bottom electrode, the second protrusion covers the second bottom electrode, the first bottom electrode is exposed in a first recessed portion between two adjacent first protrusions, and the piezoelectric layer is exposed in a first recessed portion between two adjacent first protrusions and the second protrusion.

4. The method for manufacturing a resonator according to claim 3, characterized in that: The removing of at least two first bumps so that the second electrode and the cut-off boundary layer form at least two cavities comprises: There is a gap between the first bottom electrode and the cut-off boundary layer; A through hole is provided on part of the piezoelectric body, and the through hole and the gap together form an injection port, and the etching liquid is injected through the injection port to corrode the first protruding part to form the cavity.

5. The method for manufacturing a resonator according to claim 1, characterized in that: Before manufacturing the first electrode, the manufacturing method further includes: Depositing a bonding layer on the cut-off boundary layer, wherein the bonding layer covers a surface of the cut-off boundary layer that is away from the piezoelectric layer and fills the first recessed portion; A second substrate is provided, the second substrate is bonded to a surface of the bonding layer facing away from the piezoelectric layer, and the first substrate is removed.

6. The method for manufacturing a resonator according to claim 5, characterized in that: The blocking body covers the wall surface and the bottom of the groove between two adjacent piezoelectric bodies, and extends to the surface of the piezoelectric body on one side away from the second substrate; The metal body covers a portion of the surface of the first electrode on a side facing away from the second electrode layer.

7. The method for manufacturing a resonator according to claim 1, characterized in that: The first electrode includes a first top electrode and a second top electrode arranged at intervals in a first direction, the first top electrode and the second top electrode correspond to different cavities; the first top electrode has a first side facing away from the second top electrode, and the second top electrode has a second side facing away from the first top electrode; The orthographic projection of the first side portion on the cut-off boundary layer is located in the cavity corresponding to the first top electrode, and the orthographic projection of the second side portion on the cut-off boundary layer is located in the cavity corresponding to the second top electrode.

8. The method for manufacturing a resonator according to claim 1, characterized in that: include: The width of the groove is greater than 5 μm.

9. A resonator, characterized in that: include: A first electrode layer (101), a piezoelectric layer (102), and a second electrode layer (103) are stacked; The first electrode layer (101) is provided with a plurality of second notches (1012) penetrating the first electrode layer (101) to form a plurality of first electrodes (1011) arranged at intervals; the second electrode layer (103) is provided with a plurality of first notches (1032) penetrating the first electrode layer (101) to form a plurality of second electrodes (1031) arranged at intervals; a surface of the piezoelectric layer (102) facing away from the first electrode layer (101) is exposed at the first notch (1032); and a surface of the piezoelectric layer (102) facing away from the second electrode layer (103) is exposed at the second notch (1012); The piezoelectric layer (102) is provided with a plurality of grooves (1022) penetrating the piezoelectric layer (102) to form a plurality of piezoelectric bodies (1021) arranged at intervals, the second electrode (1031) is exposed in the groove (1022), a barrier layer (108) is also provided on the piezoelectric layer (102), the barrier layer (108) at least covers the bottom of each groove (1022), and the barrier layer (108) comprises a barrier body (1081) and a metal body (1082); wherein a support layer (1081) is also provided on a surface of the second electrode layer (103) facing away from the piezoelectric layer (102) 04), the support layer (104) includes a plurality of first protrusions (1041) arranged at intervals, a first recessed portion (1042) is formed between adjacent first protrusions (1041), a surface of the first protrusion (1041) facing away from the piezoelectric layer (102) and a wall surface of the first recessed portion (1042) are covered with a cutoff boundary layer (105), and after the cutoff boundary layer (105) is formed, at least two first protrusions (1041) are removed to form at least two cavities (200) between the cutoff boundary layer (105) and the second electrode (1031).

10. The resonator according to claim 9, characterized in that The resonator further comprises a second substrate (107), wherein the second substrate (107) is connected to the cut-off boundary layer (105) via a bonding layer (106), and the bonding layer (106) is filled in the first recess (1042).

11. The resonator according to claim 10, characterized in that The first electrode (1011) comprises a first top electrode (10111) and a second top electrode (10112) arranged at intervals in a first direction, and the first top electrode (10111) and the second top electrode (10112) correspond to different cavities (200); The first top electrode (10111) has a first side portion (10) facing away from the second top electrode (10112), the second top electrode (10112) has a second side portion (11) facing away from the first top electrode (10111), the orthographic projection of the first side portion (10) on the cut-off boundary layer (105) is located in a cavity (200) corresponding to the first top electrode (10111), and the orthographic projection of the second side portion (11) on the cut-off boundary layer (105) is located in a cavity (200) corresponding to the second top electrode (10112).

12. The resonator according to claim 11, characterized in that The second electrode (1031) comprises a first bottom electrode (10311) and a second bottom electrode (10312), and the length of the first bottom electrode (10311) is greater than that of the second bottom electrode (10312); The first convex block (1041) comprises a first convex portion (10411) and a second convex portion (10412), the first convex portion (10411) covers a portion of the first bottom electrode (10311), the second convex portion (10412) covers the second bottom electrode (10312), the first bottom electrode (10311) is exposed in a first recessed portion (1042) between two adjacent first convex portions (10411), and the piezoelectric layer (102) is exposed in a first recessed portion (1042) between two adjacent first convex portions (10411) and second convex portions (10412); After the cut-off boundary layer (105) is formed, at least two first protrusions (10411) are removed, so that a cavity (200) is formed between at least two first bottom electrodes (10311) and the cut-off boundary layer (105).

13. The resonator according to claim 10, characterized in that The blocking body (1081) covers the wall and bottom of the groove (1022) between two adjacent piezoelectric bodies (1021) and extends to the surface of the piezoelectric body (1021) on the side facing away from the second electrode layer (103), and the metal body (1082) is connected to the surface of the first electrode (1011) on the side facing away from the second electrode layer (103).

14. The resonator according to claim 10, characterized in that The width of the groove (1022) is greater than 5 μm.

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