Semiconductor structure with redundancy and method of manufacture, electronic device

Abstract

The application relates to a semiconductor structure, a manufacturing method thereof and an electronic device. The assembly comprises a substrate, a plurality of bulk acoustic resonators and at least one redundant structure. At least two resonators are stacked on one side of the substrate to form a resonator stack unit. An acoustic decoupling layer is arranged between the top electrode of a lower resonator and the bottom electrode of an upper resonator, and the acoustic decoupling layer constitutes an acoustic mirror of the upper resonator. The at least one redundant structure is stacked with at least one resonator in the plurality of resonators on the one side of the substrate to form a redundant stack unit, the redundant stack unit is juxtaposed with the resonator stack unit in the horizontal direction on the one side of the substrate, the redundant structure comprises a redundant piezoelectric layer, the redundant piezoelectric layer is in the same layer as the corresponding piezoelectric layer in the resonator stack unit, and the top electrode, the piezoelectric layer and the bottom electrode of the resonator in the redundant stack unit are arranged in the same layer as the top electrode, the piezoelectric layer and the bottom electrode of the resonator in the same layer in the resonator stack unit.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the field of semiconductor, and in particular to a semiconductor structure and a method for manufacturing the same, and an electronic device having the same. BACKGROUND

[0002] With the rapid development of today's wireless communication technology, the application of small portable terminal devices is increasingly widespread, and thus the demand for high-performance, small-size radio frequency front-end modules and devices is increasingly urgent. In recent years, filter devices such as filters, duplexers, etc. based on film bulk acoustic resonators (FBAR) are increasingly favored by the market. On the one hand, because of their excellent electrical properties such as low insertion loss, steep transition characteristics, high selectivity, high power capacity, strong electrostatic discharge (ESD) resistance, etc., on the other hand, because of their small size and easy integration.

[0003] However, there is a need for further reduction in the size of filter devices in reality.

[0004] In addition, in the existing design, bulk acoustic resonators are combined in series and in parallel to form a filter, which requires the formation of multiple resonators on a substrate, and each resonator is separated at different horizontal positions on the substrate and connected by horizontal metal leads, as shown in Figure 1 The top electrode 104 of the resonator 100 is connected to the bottom electrode 102 of the resonator 200 through the conductive via 10 in the dashed box. In order to ensure the transmission of electrical signals and the limitations of the manufacturing process, the connection width of the conductive via 10 and the top electrode 104 of the resonator 100, the width of the conductive via 10, the width of the top electrode 104 of the resonator 100, and the width of the bottom electrode 102 of the resonator 200 all have certain requirements, and the total length is generally > 5 μm, which leads to a large electrical loss introduced by the connecting line, especially for high-frequency resonators, when the electrode thickness is < 1000A, which will worsen the insertion loss by more than 0.1 dB. SUMMARY

[0005] To alleviate or solve at least one aspect of the above problems in the prior art, the present application is proposed.

[0006] According to an aspect of an embodiment of the present application, a semiconductor structure is provided, comprising:

[0007] a substrate;

[0008] a plurality of resonators, each of which is a bulk acoustic wave resonator, the plurality of resonators including at least one resonator stack unit, the resonator stack unit including at least a first resonator and a second resonator stacked on a side of a substrate in a thickness direction of the substrate, the second resonator being above the first resonator, the first resonator including a first top electrode, a first piezoelectric layer, a first bottom electrode, and a first acoustic mirror, the second resonator including a second top electrode, a second piezoelectric layer, a second bottom electrode, and a second acoustic mirror,

[0009] wherein:

[0010] the semiconductor structure further includes at least one redundant structure stacked on the side of the substrate in the thickness direction of the substrate with at least one resonator of the plurality of resonators to form a redundant stack unit, the redundant stack unit being horizontally juxtaposed with the resonator stack unit on the side of the substrate, the redundant structure including a redundant piezoelectric layer which is in the same layer as a corresponding piezoelectric layer in the resonator stack unit, a top electrode, a piezoelectric layer, and a bottom electrode of a resonator in the redundant stack unit being respectively disposed in the same layer as a top electrode, a piezoelectric layer, and a bottom electrode of a resonator in the resonator stack unit in the same layer.

[0011] Embodiments of the present application also relate to a method of manufacturing a semiconductor structure, comprising:

[0012] Step 1: forming at least two first structures horizontally juxtaposed on a surface of a substrate, the at least two first structures including first resonator structures, each first resonator structure including a first bottom electrode, a first piezoelectric layer, and a first top electrode;

[0013] Step 2: disposing a patterned sacrificial material layer on the at least two first structures formed in Step 1, respectively;

[0014] Step 3: forming second structures on the at least two first structures of Step 2, respectively, the second structures including second resonator structures, the second resonator structures including second bottom electrodes, second piezoelectric layers, and second top electrodes;

[0015] Step 4: releasing the sacrificial material layers to form cavities,

[0016] wherein:

[0017] in Step 3, the first resonator structures are stacked on the second resonator structures in the thickness direction to form resonator stack units, in each resonator stack unit, the sacrificial material layer is located between the first top electrode and the second bottom electrode in the thickness direction of the substrate; and

[0018] One of the first structure and the second structure comprises a redundant structure, the redundant structure comprising at least a redundant piezoelectric layer, and in step 3, one resonator structure of the other of the first structure and the second structure is stacked with the redundant structure in a thickness direction to form a redundant stacked unit, the redundant piezoelectric layer of the redundant stacked unit being arranged in the same layer as the piezoelectric layer in the resonator stacked unit, and the top electrode, the piezoelectric layer and the bottom electrode of the resonator in the redundant stacked unit being arranged in the same layer as the top electrode, the piezoelectric layer and the bottom electrode of the resonator in the resonator stacked unit, respectively.

[0019] Embodiments of the present application also relate to an electronic device comprising the resonator assembly described above. BRIEF DESCRIPTION OF DRAWINGS

[0020] The following description and drawings can better help understand these and other features and advantages of various embodiments disclosed by the present application, in which like reference numerals refer to like parts throughout the several views of the drawings, in which:

[0021] Figure 1 schematic cross-sectional view of the electrical connection between two adjacent bulk acoustic wave resonators in a prior art design;

[0022] Figure 2 schematic top view of a semiconductor structure according to an exemplary embodiment of the present application;

[0023] Figure 3A schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present application, taken along the A-A' line in Figure 2

[0024] Figure 3B schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present application, taken along the B-B' line in Figure 2

[0025] Figure 3C schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present application, taken along the C-C' line in Figure 2

[0026] Figure 3D schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present application, taken along the C-C' line in Figure 3A Figure 1

[0027] Figure 3E-3G schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present application, taken along the C-C' line in Figure 2

[0028] Figure 4A ​​​​​​schematic diagram of a filter comprising 5 bulk acoustic wave resonators;

[0029] Figure 4B schematic cross-sectional view of the arrangement of resonators in a filter according to an exemplary embodiment of the present application, wherein a redundant structure is provided in the lower left portion; Figure 4A

[0030] Figure 4C schematic cross-sectional view of the arrangement of resonators in a filter according to an exemplary embodiment of the present application, wherein a redundant structure is provided in the lower left portion; Figure 4A

[0031] Figure 4D schematic cross-sectional view of the arrangement of resonators in a filter according to another exemplary embodiment of the present application, wherein no redundant structure is provided; Figure 4A

[0032] Figure 5A schematic diagram of another filter comprising 5 bulk acoustic wave resonators;

[0033] Figure 5B schematic cross-sectional view of the arrangement of resonators in a filter according to an exemplary embodiment of the present application, wherein a redundant structure is provided in the upper right portion; Figure 5A

[0034] Figure 6A 6B schematic cross-sectional views of the arrangement of resonators in a filter according to different exemplary embodiments of the present application, wherein the redundant structure is implemented differently;

[0035] Figure 7 schematic cross-sectional view of an example of the arrangement of resonators in a filter according to an exemplary embodiment of the present application;

[0036] Figure 8A-8G schematic diagram exemplarily showing the manufacturing process of a resonator stack unit according to an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0037] The technical solutions of the present application will be further described in detail below with reference to the embodiments and the accompanying drawings. In the description, identical or similar reference numerals indicate identical or similar components. The following description of the embodiments of the present application is intended to explain the general inventive concept of the present application, and should not be understood as a limitation of the present application. The embodiments of the present application are only a part of the embodiments, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present application.​​​​​

[0038] The reference signs in the present application are explained as follows:

[0039] 11, 21: electrode pair external lead of top electrode of upper resonator.

[0040] 12, 22: electrode pair external lead of bottom electrode of upper resonator.

[0041] 13, 23: electrode pair external lead of top electrode of lower resonator.

[0042] 14, 24: electrode pair external lead of bottom electrode of lower resonator.

[0043] 401: electrode pair external lead. The electrode pair external lead above is connected with the corresponding electrode.

[0044] S: substrate, which can be selected from single crystal silicon, gallium nitride, gallium arsenide, sapphire, quartz, silicon carbide, diamond, etc.

[0045] 101, 201: acoustic mirror, which can be a cavity, or a Bragg reflection layer or other equivalent form. Figure 3A The cavity is used in the embodiment shown.

[0046] 102, 202: bottom electrode, which can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium, or a composite of the above metals or an alloy thereof, etc.

[0047] 103, 203: piezoelectric layer, which can be a single crystal piezoelectric material, which can be selected from single crystal aluminum nitride, single crystal gallium nitride, single crystal lithium niobate, single crystal lead zirconate titanate (PZT), single crystal potassium niobate, single crystal quartz thin film, or single crystal lithium tantalate, etc. The piezoelectric layer can also be a polycrystalline piezoelectric material (corresponding to single crystal, non-single crystal material), which can be selected from polycrystalline aluminum nitride, zinc oxide, PZT, etc. The piezoelectric layer can also be a rare earth element doped material containing the above materials in a certain atomic ratio, for example, doped aluminum nitride, which contains at least one rare earth element, such as scandium (Sc), yttrium (Y), magnesium (Mg), titanium (Ti), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

[0048] 104, 204: top electrode, which can be the same material as the bottom electrode, and can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium, or a composite of the above metals or an alloy thereof, etc. The top electrode and the bottom electrode are generally the same material, but can also be different.

[0049] 105, 205: passivation layer, typically a dielectric material such as silicon dioxide, aluminum nitride, silicon nitride, etc.

[0050] 106, 206: disconnection structure.

[0051] Figure 2 Fig. 6 is a schematic top view of a semiconductor structure according to an exemplary embodiment of the application, and Figure 2 Fig. 6 is a schematic top view of a semiconductor structure according to an exemplary embodiment of the application, and

[0052] Figure 3A Fig. 7 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the application taken along the A-A' line in Figure 2 Fig. 7 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the application taken along the A-A' line in

[0053] Although not shown, a process layer can also be provided on the top electrode of the resonator, which can cover the top electrode, and which can serve as a mass- tuning load or a passivation layer. The material of the passivation layer can be a dielectric material such as silicon dioxide, aluminum nitride, silicon nitride, etc.

[0054] In addition, in the structure shown in Figure 3A Fig. 6, two resonators are formed at the same horizontal position of the substrate S, which differ in their spatial position in the vertical direction or in the thickness direction of the substrate.

[0055] As will be appreciated by those skilled in the art, three resonators or more can also be stacked. For example, the resonator assembly comprises a first resonator, a second resonator and a third resonator stacked in the thickness direction, with an acoustic decoupling layer 201 (in this embodiment a cavity) between the top electrode 104 of the first resonator and the bottom electrode 202 of the second resonator, and with a further acoustic decoupling layer between the top electrode 204 of the second resonator and the bottom electrode of the third resonator, which constitutes an acoustic mirror of the third resonator.

[0056] In the structure shown in Figure 3A Fig. 6, two resonators are formed at the same horizontal position of the substrate S, which differ in their spatial position in the vertical direction or in the thickness direction of the substrate.

[0057] Correspondingly, in the case of stacking the first resonator, the second resonator and the third resonator, the effective area of the uppermost third resonator is the overlapping area of its top electrode, piezoelectric layer, bottom electrode and the other acoustic decoupling layer in the thickness direction, the effective area of the middle second resonator is the overlapping area of the other acoustic decoupling layer, top electrode 204, piezoelectric layer 203, bottom electrode 202 and cavity 201 in the thickness direction, and the effective area of the lowermost first resonator is the overlapping area of cavity 201, top electrode 104, piezoelectric layer 103, bottom electrode 102 and cavity 101 in the thickness direction.

[0058] In Figure 3A the structure shown, the upper resonator and the lower resonator are acoustically separated by cavity 201, i.e. the cavity 201 constitutes an acoustic decoupling layer between the upper and lower resonators, thereby also avoiding the problem of acoustic coupling that can be caused by the adjacent stacking of the upper and lower resonators.

[0059] In Figure 3A the structure shown, because multiple resonators are formed at the same horizontal position of the substrate S, the spatial positions of the multiple resonators in the vertical direction or in the thickness direction of the substrate are different, and thus the area of the filter can be greatly reduced. For example, in the case of arranging two resonators, the area P2 shown in Figure 1 may be reduced to the area P1 shown in Figure 3A .

[0060] As shown in Figure 3A , the bottom electrode 202 of the upper resonator and the top electrode 104 of the lower resonator are electrically connected to each other at the non-electrode connection end. In the case of directly connecting the bottom electrode of the upper resonator to the top electrode of the lower resonator, the bottom electrode of the upper resonator and the top electrode of the lower resonator are directly electrically connected, and the length of the connection part is shorter than the length of the connection part shown in Figure 1 , i.e. the transmission path is shortened, and the transmission loss is reduced; in addition, the thickness of the metal through which the electrical signal is output is the sum of the thicknesses of the top electrode of the lower resonator and the bottom electrode of the upper resonator, and the transmission loss is further reduced. By reducing the electrical loss, the insertion loss of the final filter is optimized. As shown in Figure 3A , the length of the transmission path formed by the bottom electrode of the upper resonator and the top electrode of the lower resonator is d, which can be less than 5 μm.

[0061] Using the structure shown in Figures 3A-3C, the current transmission path to the lower resonator is shortened, for example, to less than 5 μm, reducing transmission loss. This allows for thinner top electrode 104 of the lower resonator and bottom electrode 202 of the upper resonator, facilitating further miniaturization of the resonator. With the bottom electrode of the upper resonator and the top electrode of the lower resonator electrically connected, the circuit transmission path loss to the bottom electrode of the upper resonator and the current transmission path loss to the top electrode of the lower resonator can be reduced, while simultaneously decreasing the electrode film thickness of both the bottom and top electrodes of the upper resonator. Correspondingly, when the resonant frequency of the lower resonator is greater than 0.5 GHz, the thickness of the top electrode 104 is less than... And / or when the resonant frequency of the upper resonator is greater than 0.5 GHz, the thickness of the bottom electrode 202 is less than In a further embodiment, when the resonant frequency of the lower resonator is greater than 3 GHz, the thickness of the top electrode 104 can be designed to be less than [a certain value]. And / or, when the resonant frequency of the upper resonator is greater than 3 GHz, the thickness of the bottom electrode 202 of the upper resonator can also be less than 3 GHz. As will be understood, in this invention, the thinning of the electrode thickness refers to the thinning of the portion of the electrode within the effective region of the resonator.

[0062] Figure 3D For illustrative purposes only Figure 3A The structure relative to Figure 1 A comparison of insertion loss curves for the structures. Figure 3D This invention is used in the 3.5G frequency band. Figure 3A The insertion loss curve (solid line) after the structure is compared with that after using Figure 1 A comparison of the insertion loss curve (dashed line) of the traditional structure shows that the method using the present invention... Figure 3A After the structure is completed, the insertion loss is increased by approximately 0.1 dB due to the reduction in electrode loss.

[0063] Figure 3B For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of the bulk acoustic resonator intercepted by the B-B' line. Figure 3C For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of the bulk acoustic resonator intercepted by the C-C' line. It can be seen that, in... Figure 3B and 3C In the middle, the top electrode of the lower resonator and the bottom electrode of the upper resonator are electrically connected in the circumferential direction around the entire cavity 201.

[0064] When the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically connected to each other, Figure 3A-3CIn the structure shown, the bottom electrode of the upper resonator and the non-electrode connection terminals and electrode connection terminals of the top electrode of the lower resonator are all connected to each other, forming an electrical connection around the entire circumference of the cavity 201. However, besides... Figure 3A-3C Besides the connection method shown, other connection methods are also possible. For example, the bottom electrode of the upper resonator and the top electrode of the lower resonator may be electrically connected to each other only at some of the non-electrode connection terminals; or, the bottom electrode of the upper resonator and the top electrode of the lower resonator may be electrically connected to each other only at the electrode connection terminals; or, the bottom electrode of the upper resonator and the top electrode of the lower resonator may be electrically connected to each other only at all or some of the non-electrode connection terminals. These are all within the protection scope of this invention.

[0065] Figure 7 The right-hand view shows a specific example of the bottom electrode of the upper resonator and the top electrode of the lower resonator being electrically connected to each other. (See attached image.) Figure 7 As shown in the left cross-sectional view, the top electrode 104 is covered by a piezoelectric layer 103, and the bottom electrode 202 is connected to the top electrode 104 at both the electrode connection end and the non-electrode connection end. Figure 7 In the right-side view, the electrode connection end of the bottom electrode 202 covers the electrode connection end of the top electrode 104, and the non-electrode connection end of the bottom electrode 202 covers the non-electrode connection end of the top electrode 104.

[0066] When the ratio of the maximum effective width of the resonator to the cavity height is large, the upper and lower resonators may come into contact within the cavity due to bending or other reasons. For example, if the cavity height is... When the maximum width of the effective region of the resonator is greater than 100μm, in order to ensure the complete formation of the cavity 201 within the effective regions of the upper and lower resonators, the stress of the lower resonator can be controlled to bend it downward toward the air cavity, and / or the stress of the upper resonator can be controlled to bend it upward toward the air cavity. The top electrode of the lower resonator is concave downward, and / or the top electrode of the upper resonator is convex upward.

[0067] As mentioned earlier, stress can be controlled to reduce the probability of the upper and lower resonators coming into contact with each other. However, when the resonator area is large, although not shown, a support can be added. This support can contact the top or top electrode of the lower resonator, and the height of the support must be less than or equal to the cavity height. Equal means that the top of the support contacts the bottom or bottom electrode of the upper resonator. The height of the support is less than the cavity height, which means that the top of the support does not contact the upper resonator. When the cavity thickness is reduced locally due to the bending of the resonator, the top of the support will contact the upper resonator and play a supporting role.

[0068] Compared to the scheme mentioned later that uses a Bragg reflector layer as the acoustic decoupling layer, using cavity 201 as the acoustic decoupling layer achieves complete acoustic decoupling of the upper and lower resonators, resulting in superior resonator performance. Furthermore, cavity 201 is directly surrounded by the top electrode 104 of the lower resonator and the bottom electrode 202 of the upper resonator (in other embodiments, the structure defining the cavity location also includes the piezoelectric layers of the upper and / or lower resonators), for example... Figure 3A-3C In the case of the structures shown in 4B-4D and 7, the overall structure is stable and reliable and the processing technology is simple.

[0069] Alternatively, a Bragg reflector layer can be used instead of the above-mentioned one. Figure 3A-3C Cavity 201 is shown in 4B-4D and 7. Using a Bragg reflector layer instead of the intermediate cavity, although it increases the acoustic coupling between the upper and lower resonators and increases the complexity of the filter design, it also increases the freedom of filter design and improves the mechanical stability of the overall structure.

[0070] As those skilled in the art will understand, the cavity 201 disposed between the bottom electrode of the upper resonator and the top electrode of the lower resonator in the thickness direction of the resonator includes not only the case where at least a portion of the upper and lower boundaries of the cavity is defined by the lower surface of the bottom electrode of the upper resonator and the upper surface of the top electrode of the lower resonator, but also the case where a process layer (e.g., a passivation layer) is disposed on the upper surface of the top electrode of the lower resonator, thereby defining at least a portion of the lower boundary of the cavity 201. All of these are within the scope of protection of this invention.

[0071] exist Figure 3A-3C In the accompanying drawings 4B-4D, the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically connected to each other, but the present invention is not limited thereto. In two stacked bulk acoustic resonators, the bottom electrode of the upper resonator and the top electrode of the lower resonator can also be electrically isolated from each other, for example, see [reference needed]. Figure 7 The left-side view.

[0072] Figure 3E For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of a bulk acoustic resonator intercepted by line A-A'. Figure 3E In the middle, the bottom electrode 202 of the upper resonator and the top electrode 104 of the lower resonator are not electrically connected. The non-electrode connection end of the bottom electrode 202 of the upper resonator is located outside the top electrode 104 of the lower resonator and is located on the upper surface of the piezoelectric layer 103 of the lower resonator.

[0073] Figure 3F For an exemplary embodiment of the present invention, along Figure 2The schematic cross-sectional view of the bulk acoustic resonator taken by the B-B' line shows that the non-electrode connection terminal of the bottom electrode 202 of the upper resonator is not electrically connected to the non-electrode connection terminal of the top electrode 104 of the lower resonator. A portion of the end of the non-electrode connection terminal of the bottom electrode of the upper resonator is disposed on the upper surface of the piezoelectric layer 103 of the lower resonator (see Figure 103). Figure 3F (Left side of the image) while the other end is located inside the boundary of the shared cavity in the lateral direction (see image). Figure 3F (The right side of the middle).

[0074] Figure 3G For an exemplary embodiment of the present invention, along Figure 2 The schematic cross-sectional view of the bulk acoustic resonator taken by the C-C' line shows that the non-electrode connection terminal of the bottom electrode 202 of the upper resonator is not electrically connected to the non-electrode connection terminal of the top electrode 104 of the lower resonator, and the electrode connection terminal of the bottom electrode 202 of the upper resonator is not electrically connected to the electrode connection terminal of the top electrode 104 of the lower resonator. More specifically, for example, refer to... Figure 7 The left-side cross-sectional view. The top electrode 104 is located in the first electrode layer. Figure 7 In the left-hand view, the first electrode layer includes a top electrode 104 and a non-top electrode layer located outside the non-electrode connection terminal of the top electrode 104 via a disconnect structure 106. Figure 7 (The left side of the broken structure 106). Figure 7 In the middle, the bottom electrode 202 is located in the second electrode layer, such as Figure 7 As shown in the left-hand view, the second electrode layer includes a bottom electrode 202 and a non-bottom electrode layer located outside the non-electrode connection terminal of the bottom electrode 202, electrically isolated from the non-electrode connection terminal of the bottom electrode 202 via a disconnection structure 206. Figure 7 (The right side of the disconnected structure 206). Figure 7 In the left-hand view, the electrode connection end of the bottom electrode 202 covers the non-top electrode layer, and the non-bottom electrode layer covers the electrode connection end of the top electrode 104.

[0075] Figure 4A This is a schematic diagram of a filter that includes five sonic resonators, showing three series resonators Se1-Se3 and two parallel resonators Sh1-Sh2. The series and parallel resonators have different resonant frequencies, thus forming a bandpass filter. Figure 4B This is an exemplary illustration of an exemplary embodiment of the present invention. Figure 4A A schematic cross-sectional view of the resonator arrangement in the filter, with a redundant structure set in the lower left part.

[0076] To improve the stability of the process, in Figure 4BIn this example, the series resonator Se1 is positioned above a non-functional structure with the height of a parallel resonator, ensuring that Se1 is on the same plane as the other series resonators Se2 and Se3. Here, the "non-functional structure with the height of a parallel resonator" corresponds to a dummy structure. For example... Figure 4B As shown, the left side has a redundant structure at the bottom of the series resonator Se1. This redundant structure also has a redundant top electrode, a redundant piezoelectric layer, and a redundant bottom electrode. The redundant top electrode, redundant piezoelectric layer, and redundant bottom electrode of the redundant structure layer are arranged in the same layer as the top electrode 104, piezoelectric layer 103, and bottom electrode 102, respectively. However, as a redundant structure, it does not have the function of a resonator, for example, in... Figure 4B In the diagram shown, the redundant structure does not have an acoustic mirror cavity below it. Alternatively, the redundant structure can be made to function as a resonator by de-energizing the redundant top or bottom electrode, or by connecting the redundant top and bottom electrodes together.

[0077] Figure 4B In the diagram, the series resonator Se2 is located above the parallel resonator Sh1, and the series resonator Se3 is located above the parallel resonator Sh2. The series resonator Se2 and the parallel resonator Sh1 form a resonator stacking unit, and the series resonator Se3 and the parallel resonator Sh2 form a resonator stacking unit.

[0078] In addition, Figure 4B In this configuration, a redundant resonator or redundant structure is positioned below the series resonator Se1. Furthermore, since the redundant resonator does not participate in the filter's operation, it may not require an acoustic mirror. For example... Figure 4B As shown, the acoustic mirror cavity 101 is not located below the redundant structure; therefore, the redundant structure does not function as a resonator. The redundant structure is stacked with the series resonator Se1 to form a redundant stacked unit.

[0079] Without redundant resonators, the following will occur: Figure 4D The structure shown. Figure 4D This is an exemplary illustration of another exemplary embodiment of the present invention. Figure 4A A schematic cross-sectional view of the resonator arrangement in the filter. Figure 4D and Figure 4B The difference is that, in Figure 4D In this case, the series resonator Se1 is directly placed on the substrate without any redundant structure. Because Se1 is not at the same height as the other series resonators, a thickness difference will occur during film growth. The thickness of each layer of Se1 will differ significantly from the thickness of the other series resonators. This will lead to uncontrollable frequency of Se1, inconsistent frequencies with the other series resonators, and ultimately, a degraded filter performance.

[0080] As shown in Figure 4B , the controllability of the resonance frequency of the series resonator Se1 can be ensured after it is pushed to the similar height as other series resonators by the redundant resonator. The redundant resonator can be made together with other lower resonators, such as the parallel resonators Sh1 and Sh2.

[0081] In order to ensure that the redundant resonator does not affect the operation of the series resonator Se1 and other resonators, the redundant resonator needs to be electrically and acoustically isolated from other resonators. The acoustic isolation is achieved by the cavity between the redundant resonator and the series resonator Se1.

[0082] In the resonator arrangement of the single filter shown in Figure 4B , the characteristics of the stacked resonators are fully utilized, and the bottom electrode of the upper resonator is interconnected with the top electrode of the lower resonator.

[0083] In Figure 4B , 401 is an electrode external lead, for example, on the right side of Figure 4B , the external lead 401 is electrically connected to the top electrode of the upper resonator of the middle stacked unit and the top electrode of the lower resonator of the right stacked unit. It should be noted that the arrangement of the electrode lead 401 is only exemplary, and other ways can also be used to achieve the electrical connection of the electrodes of the resonators.

[0084] Figure 7 is a cross-sectional view of the resonator arrangement of the filter according to an exemplary embodiment of the present application, in which the upper and lower resonators are acoustically isolated by a cavity.

[0085] In Figure 7 , the upper and lower resonators on the left side constitute a resonator stacked unit, and in the right side view, the lower resonator is a redundant resonator or a redundant structure due to the absence of the cavity 101, and the redundant structure constitutes a redundant stacked unit with the upper resonator. For convenience of description, in the description of the embodiment of Figure 7 , the redundant resonator is also denoted as the lower resonator.

[0086] In Figure 7 , the bottom electrode 202 of the upper resonator and the top electrode 104 of the lower resonator can be directly electrically connected outside the effective area, as shown on the right side of Figure 7 ; in addition, the bottom electrode 202 of the upper resonator and the top electrode 104 of the lower resonator can also be electrically isolated outside the effective area, as shown in the left side view of Figure 7 . It has been described above that the electrode connection of the upper and lower resonators in the resonator stacked unit on the left side of Figure 7 , and the electrode connection of the upper and lower resonators in the redundant stacked unit on the right side of Figure 7 , and will not be repeated here.

[0087] In the above embodiments, for the stacked units, there are two types, one is that the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically connected to each other, and the other is that the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically isolated from each other. The following refers to Figure 8A-8G for exemplary illustration Figure 7 schematic diagram of the manufacturing process of the structure shown, wherein the left part of each figure corresponds to the bottom electrode of the upper resonator and the top electrode of the lower resonator in the resonator stacked unit being electrically isolated from each other, and the right part corresponds to the bottom electrode of the upper resonator and the top electrode of the lower resonator in the redundant stacked unit being electrically connected to each other.

[0088] Step 1: As shown in Figure 8A , the lower resonator in the resonator stacked unit is manufactured by a conventional FBAR process, which includes a recess corresponding to the acoustic mirror cavity 101, a sacrificial material is arranged in the recess; a bottom electrode 102; a piezoelectric layer 103; a top electrode 104; a passivation layer 105. As can be understood, the passivation layer 105 can also not be arranged. In addition, Figure 8A , the acoustic mirror in Figure 8A , the top electrode 104 covers the piezoelectric layer 103. In step 1, the lower resonator in the redundant stacked unit or the redundant resonator is formed at the same time, which is different from the bulk acoustic wave resonator on the left in that the acoustic mirror cavity 101 is not arranged in the substrate.

[0089] Step 2: For the upper and lower resonators that are not electrically connected, the external lead of the top electrode 104 of the lower resonator and the bottom electrode 202 of the upper resonator needs to be disconnected. In the redundant stacked unit and the resonator stacked unit, as shown in Figure 8B , a disconnection structure 106 corresponding to an opening or a via (as can be understood, the via is a strip-shaped via) can be manufactured by photolithography and etching.

[0090] Step 3: As shown in Figure 8C , in the redundant stacked unit and the resonator stacked unit, a sacrificial layer (such as PSG (phosphosilicate glass), amorphous silicon, BSG (borosilicate glass), BPSG (borophosphosilicate glass), USG (silica glass), etc.) is deposited on the structure formed in step 2, and in order to ensure the film quality of the subsequent upper resonator, the surface of the deposited sacrificial material layer can be planarized by CMP (chemical mechanical polishing) method. In Figure 8C , as shown on the left side, the sacrificial material fills the disconnection structure 106.

[0091] Step 4: As shown in Figure 8DAs shown, in the redundant stacked units and the resonator stacked units, a patterning etching process is performed on the sacrificial material layer and the passivation layer of the lower resonator to expose the external leads of the top electrode of the lower resonator, so as to facilitate electrical connection with the external leads of the bottom electrode of the upper resonator. The patterned sacrificial material layer forms a sacrificial layer, which is eventually removed to form a cavity 21 that acoustically isolates the upper and lower resonators. Optionally, an acoustic reflection structure (e.g., a Bragg reflector layer) can be deposited for acoustic isolation of the upper and lower resonators.

[0092] Step 5: As Figure 8E As shown, in the redundant stacked units and the resonator stacked units, in Figure 8D In the structure shown, an electrode metal layer for forming the bottom electrode 202 of the upper resonator is deposited using processes such as sputtering or evaporation. For Figure 8E The left-side upper and lower resonators are not electrically connected. The electrode metal layer corresponding to the bottom electrode 202 is patterned using photolithography and etching processes to form... Figure 8E The structure shown is in Figure 8E In the left-hand diagram, the external leads of the bottom electrode 202 of the upper resonator and the top electrode 104 of the lower resonator are disconnected due to the disconnect structure 206. The disconnect structure 206 corresponds to an opening or through-hole (if understood, a through-hole is a strip-shaped through-hole). Figure 8E As can be seen, the top electrode 104 is part of the first electrode layer, and the bottom electrode 202 is part of the second electrode layer, with the second electrode layer covering the first electrode layer. At the non-electrode connection end of the top electrode 104, as shown in the figure... Figure 8E On the left side of the left figure, the electrode connection end of the bottom electrode 202 covers the first electrode layer, while the electrode connection end of the top electrode 104 is covered by the second electrode layer.

[0093] Step 6: As Figure 8F As shown, in the redundant stacked units and the resonator stacked units, in Figure 8E On the structure shown, the piezoelectric layer 203, top electrode 204, and passivation layer 205 of the upper resonator are deposited and patterned.

[0094] Step 7: As Figure 8G As shown, the fabrication of the external electrode leads and the release of the sacrificial material layer are completed to form cavity 201 and acoustic mirror cavity 101.

[0095] It should be noted that for redundant resonators or redundant structures in redundant stacked units, at least a redundant piezoelectric layer is included. This redundant piezoelectric layer is disposed on the same layer as the piezoelectric layer of the corresponding resonator in the resonator stacked unit juxtaposed with the redundant stacked unit. Redundant resonators may not include acoustic mirrors (see, for example, [link to relevant documentation]). Figure 4B ), may not have redundant top electrodes (e.g. Figure 6B) or a redundant bottom electrode (e.g. Figure 6A ) or a redundant top electrode and a redundant bottom electrode are electrically connected to each other (e.g. Figure 4C ) or a redundant top electrode and a redundant bottom electrode are electrically connected to each other (e.g. Figure 5B ).

[0096] In the above embodiments, only one redundant structure and one resonator are provided in the redundant stack unit, and only two resonators are provided in the resonator stack unit, but the present application is not limited thereto. For example, each resonator stack unit includes three resonators, and the redundant stack unit includes one redundant structure and two resonators or one resonator and two redundant structures.

[0097] In the above embodiments, the acoustic decoupling layer exists between the corresponding upper electrode and lower electrode in the resonator stack unit or the redundant structure corresponding stack unit of the semiconductor structure. However, the present application is not limited thereto, and other stacking modes can also be used, such as providing a support structure between the stacked upper and lower resonators, the support structure being made of a non-conductive material to separate the upper and lower resonators.

[0098] It should be noted that in the present application, each numerical range, in addition to the end point value, can also be the median value of the numerical range, which is within the protection scope of the present application.

[0099] In the present application, up and down are relative to the bottom surface of the substrate of the resonator. For a component, the side close to the bottom surface is the lower side, and the side away from the bottom surface is the upper side.

[0100] In the present application, inner and outer are relative to the center of the effective area of the resonator (i.e. the effective area center) in the lateral direction or the radial direction. The side or end of a component close to the effective area center is the inner side or end, and the side or end of the component away from the effective area center is the outer side or end. For a reference position, the inner side of the position means between the position and the effective area center in the lateral direction or the radial direction, and the outer side of the position means farther away from the effective area center than the position in the lateral direction or the radial direction.

[0101] As a person skilled in the art can understand, the bulk acoustic wave resonator according to the present application can be used to form a filter or an electronic device. The electronic device herein includes but is not limited to intermediate products such as radio frequency front end, filter amplification module, and terminal products such as mobile phone, WIFI, and unmanned aerial vehicle.

[0102] Based on the above, the present application proposes the following technical solutions:

[0103] 1. A semiconductor structure, comprising:

[0104] a substrate;

[0105] a plurality of resonators each being a bulk acoustic wave resonator, the plurality of resonators including at least one resonator stack unit including at least a first resonator and a second resonator stacked on a side of the substrate in a thickness direction of the substrate, the second resonator being above the first resonator, the first resonator including a first top electrode, a first piezoelectric layer, a first bottom electrode, and a first acoustic mirror, the second resonator including a second top electrode, a second piezoelectric layer, a second bottom electrode, and a second acoustic mirror,

[0106] wherein:

[0107] the semiconductor structure further includes at least one redundancy structure stacked on the side of the substrate in the thickness direction of the substrate with at least one resonator of the plurality of resonators to form a redundancy stack unit, the redundancy stack unit being horizontally juxtaposed with the resonator stack unit on the side of the substrate, the redundancy structure including a redundancy piezoelectric layer which is in-situ with a corresponding piezoelectric layer in the resonator stack unit, a top electrode, a piezoelectric layer, and a bottom electrode of a resonator in the redundancy stack unit being in-situ arranged with a top electrode, a piezoelectric layer, and a bottom electrode of a resonator in-situ in the resonator stack unit, respectively.

[0108] 2. The semiconductor structure according to 1, wherein:

[0109] the redundancy structure further includes a redundancy top electrode adapted to be disposed on an upper surface of the redundancy piezoelectric layer and / or a redundancy bottom electrode adapted to be disposed on a lower surface of the redundancy piezoelectric layer, and the redundancy electrodes of the redundancy structure layer are in-situ arranged with corresponding electrodes of resonators in-situ in the resonator stack unit.

[0110] 3. The semiconductor structure according to 2, wherein:

[0111] the redundancy structure includes a redundancy top electrode, a redundancy piezoelectric layer, and a redundancy bottom electrode.

[0112] 4. The semiconductor structure according to 3, wherein:

[0113] in the redundancy stack unit, a second acoustic decoupling structure is disposed between electrodes adjacent to and opposite to each other in the thickness direction.

[0114] 5. The semiconductor structure according to 4, wherein:

[0115] one of the redundant structures in the redundant stack is arranged in the same layer as the first resonator in the resonator stack, the second acoustic decoupling structure being arranged between the redundant top electrode of the one of the redundant structures and the bottom electrode of an adjacently stacked resonator in the redundant stack.

[0116] 6. The semiconductor structure of 5, wherein:

[0117] the first bottom electrode is disposed on an upper surface of the substrate;

[0118] the redundant structure arranged in the same layer as the first resonator is free of an acoustic mirror on a lower side thereof.

[0119] 7. The semiconductor structure of 4, wherein:

[0120] one of the redundant structures in the redundant stack is arranged in the same layer as the second resonator in the resonator stack, the second acoustic decoupling structure being arranged between the redundant bottom electrode of the one of the redundant structures and the top electrode of an adjacently stacked resonator in the redundant stack.

[0121] 8. The semiconductor structure of any one of 5-7, wherein:

[0122] each resonator stack includes only two resonators, and the redundant stack includes one redundant structure and one resonator.

[0123] 9. The semiconductor structure of any one of 5-7, wherein:

[0124] each resonator stack includes three resonators, and the redundant stack includes one redundant structure and two resonators or one resonator and two redundant structures.

[0125] 10. The semiconductor structure of 4, wherein:

[0126] the redundant top electrode and the redundant bottom electrode of the redundant structure are connected to each other.

[0127] 11. The semiconductor structure of 4, wherein:

[0128] the redundant top electrode or the redundant bottom electrode of the redundant structure is electrically isolated from an outside.

[0129] 12. The semiconductor structure of any one of 1-11, wherein:

[0130] in the resonator stack, a first acoustic decoupling layer is arranged between the first top electrode and the second bottom electrode, the second acoustic mirror comprising the first acoustic decoupling layer.

[0131] 13. The semiconductor structure of 12, wherein:

[0132] The electrodes on the upper and lower sides of each acoustic decoupling layer are respectively an upper electrode and a lower electrode;

[0133] The upper electrode and the lower electrode corresponding to the at least one acoustic coupling layer are electrically connected.

[0134] 14. The semiconductor structure according to 13, wherein:

[0135] The end of the non-electrode connecting end of the lower electrode and the end of the non-electrode connecting end of the upper electrode are in contact with each other to achieve electrical connection between the upper electrode and the lower electrode; or

[0136] The electrode connecting end of the lower electrode and the electrode connecting end of the upper electrode are electrically connected to achieve electrical connection between the upper electrode and the lower electrode.

[0137] 15. The semiconductor structure according to 13, wherein:

[0138] The electrode connecting end of the lower electrode and the electrode connecting end of the upper electrode are electrically connected to each other, and the non-electrode connecting end of the lower electrode and the non-electrode connecting end of the upper electrode are electrically connected to each other.

[0139] 16. The semiconductor structure according to 12, wherein:

[0140] The electrodes on the upper and lower sides of each acoustic decoupling layer are respectively an upper electrode and a lower electrode;

[0141] The upper electrode and the lower electrode of the at least one acoustic decoupling structure are electrically isolated from each other.

[0142] 17. The semiconductor structure according to 16, wherein:

[0143] The end of at least a part of the non-electrode connecting end of the upper electrode in the circumferential direction or the end of the electrode connecting end of the upper electrode is disposed on the upper surface of the piezoelectric layer below the upper electrode, and the end is located outside the non-electrode connecting end of the lower electrode in the horizontal direction.

[0144] 18. The semiconductor structure according to 17, wherein:

[0145] The end of at least a part of the non-electrode connecting end of the upper electrode in the circumferential direction or the end of the electrode connecting end of the upper electrode is disposed on the upper surface of the piezoelectric layer below the upper electrode, and the end of another part of the non-electrode connecting end of the upper electrode in the circumferential direction is located inside the boundary of the corresponding acoustic decoupling layer in the horizontal direction.

[0146] 19. The semiconductor structure according to 18, wherein:

[0147] The resonator stack unit comprises a first electrode layer and a second electrode layer;

[0148] The first electrode layer includes a lower electrode and a non-lower electrode layer electrically isolated from a non-electrode connecting end of the lower electrode and located outside the non-electrode connecting end of the lower electrode;

[0149] The second electrode layer includes an upper electrode and a non-upper electrode layer electrically isolated from a non-electrode connecting end of the upper electrode and located outside the non-electrode connecting end of the upper electrode;

[0150] The electrode connecting end of the upper electrode covers the non-lower electrode layer, and the non-upper electrode layer covers the electrode connecting end of the lower electrode.

[0151] 20. The bulk acoustic wave resonator assembly of claim 4 or 12, wherein:

[0152] Each acoustic decoupling layer includes a cavity.

[0153] 21. A method of manufacturing a semiconductor structure, comprising:

[0154] Step 1: forming at least two first structures horizontally juxtaposed on a surface of a substrate, the at least two first structures including first resonator structures, each first resonator structure including a first bottom electrode, a first piezoelectric layer, and a first top electrode;

[0155] Step 2: disposing a patterned sacrificial material layer on the at least two first structures formed in Step 1, respectively;

[0156] Step 3: forming second structures on the at least two first structures of Step 2, respectively, the second structures including second resonator structures, the second resonator structures including a second bottom electrode, a second piezoelectric layer, and a second top electrode;

[0157] Step 4: releasing the sacrificial material layer to form cavities,

[0158] wherein:

[0159] In Step 3, the first resonator structures and the corresponding second resonator structures are stacked in a thickness direction to form resonator stacked units, in each resonator stacked unit, the sacrificial material layer is located between the first top electrode and the second bottom electrode in the thickness direction of the substrate; and

[0160] One of the first structures and the second structures includes a redundant structure, the redundant structure including at least a redundant piezoelectric layer, and in Step 3, one resonator structure of the other of the first structures and the second structures and the redundant structure are stacked in a thickness direction to form a redundant stacked unit, the redundant piezoelectric layer of the redundant stacked unit is arranged in the same layer as the piezoelectric layer in the resonator stacked unit, and the top electrode, the piezoelectric layer, and the bottom electrode of the resonator in the redundant stacked unit are arranged in the same layer as the top electrode, the piezoelectric layer, and the bottom electrode of the resonator in the resonator stacked unit, respectively.

[0161] 22. The method of 21, wherein:

[0162] the redundancy structure comprises the redundancy piezoelectric layer, and a redundancy top electrode and / or a redundancy bottom electrode, the redundancy top electrode is adapted to be disposed on an upper surface of the redundancy piezoelectric layer, the redundancy bottom electrode is adapted to be disposed on a lower surface of the redundancy piezoelectric layer, and in step 3, the redundancy electrodes of the redundancy structure layer are arranged in the same layer as the corresponding electrodes of the resonator in the same layer in the resonator stack unit.

[0163] 23. The method of 22, wherein:

[0164] the redundancy structure comprises the redundancy piezoelectric layer, a redundancy top electrode and a redundancy bottom electrode; and

[0165] the top electrode of the first structure and the bottom electrode of the second structure in each of the two stack units are electrically connected to each other; or the top electrode of the first structure and the bottom electrode of the second structure in each of the two stack units are electrically isolated from each other; or the top electrode of the first structure and the bottom electrode of the second structure in one of the two stack units are electrically isolated from each other, and the top electrode of the first structure and the bottom electrode of the second structure in the other of the two stack units are electrically connected to each other.

[0166] 24. The method of 23, wherein:

[0167] the top electrode of the first structure and the bottom electrode of the second structure in at least one of the two stack units are electrically isolated from each other;

[0168] in step 1, the first structure in at least one of the stack units comprises a first electrode layer covering the piezoelectric layer thereof, and the step 1 comprises a step of forming a first disconnecting structure on the first electrode layer to divide the first electrode layer into the top electrode of the first structure and a non-top electrode layer electrically isolated from a non-electrode connecting end of the top electrode of the first structure and outside of the non-electrode connecting end of the top electrode of the first structure;

[0169] in step 2, the sacrificial material layer also fills the first disconnecting structure;

[0170] in step 3, the second structure comprises a second electrode layer covering the first electrode layer, and the step 3 comprises a step of forming a second disconnecting structure on the second electrode layer to divide the second electrode layer into the bottom electrode of the second structure and a non-bottom electrode layer electrically isolated from a non-electrode connecting end of the bottom electrode of the second structure and outside of the non-electrode connecting end of the bottom electrode of the second structure;

[0171] In step 4, the sacrificial material layer in the first and second disconnecting structures is removed.

[0172] 25. The method of 23, wherein:

[0173] In two of the stacked units that are horizontally adjacent and juxtaposed, the top electrode of the first structure and the bottom electrode of the second structure in at least one of the stacked units are electrically connected to each other;

[0174] In step 1, the first structure in at least one of the stacked units includes a top electrode of the first structure that covers a piezoelectric layer of the first structure;

[0175] In step 3, the second structure in at least one of the stacked units includes a bottom electrode of the second structure that covers and electrically connects the top electrode of the first structure at an electrode connecting end and / or a non-connecting end of the bottom electrode of the second structure.

[0176] 26. An electronic device comprising the semiconductor structure of any one of 1-20.

[0177] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary and that changes can be made to these embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

Claims

1. A semiconductor structure, comprising: a substrate; a plurality of resonators, each of which is a bulk acoustic wave resonator, the plurality of resonators comprising at least one resonator stack unit, the resonator stack unit comprising at least a first resonator and a second resonator stacked on a side of the substrate in a thickness direction of the substrate, the second resonator being above the first resonator, the first resonator comprising a first top electrode, a first piezoelectric layer, a first bottom electrode and a first acoustic mirror, the second resonator comprising a second top electrode, a second piezoelectric layer, a second bottom electrode and a second acoustic mirror, wherein: the semiconductor structure further comprises at least one redundant structure without resonator function, the at least one redundant structure being stacked with at least one resonator of the plurality of resonators on the side of the substrate in the thickness direction of the substrate to form a redundant stack unit, the redundant stack unit being horizontally juxtaposed with the resonator stack unit on the side of the substrate, the redundant structure comprising a redundant piezoelectric layer, the redundant piezoelectric layer being in the same layer as a corresponding piezoelectric layer in the resonator stack unit, a top electrode, a piezoelectric layer and a bottom electrode of a resonator in the redundant stack unit being arranged in the same layer as a top electrode, a piezoelectric layer and a bottom electrode of a resonator in the same layer in the resonator stack unit, respectively. 2.The semiconductor structure according to claim 1, wherein: the redundant structure is further comprising a redundant top electrode and / or a redundant bottom electrode, the redundant top electrode being adapted to be arranged on an upper surface of the redundant piezoelectric layer, the redundant bottom electrode being adapted to be arranged on a lower surface of the redundant piezoelectric layer, and the redundant electrodes of the redundant structure layer being arranged in the same layer as corresponding electrodes of resonators in the same layer in the resonator stack unit. 3.The semiconductor structure according to claim 2, wherein: the redundant structure comprises a redundant top electrode, a redundant piezoelectric layer and a redundant bottom electrode. 4.The semiconductor structure according to claim 3, wherein: in the redundant stack unit, a second acoustic decoupling structure is arranged between electrodes adjacent to and opposite to each other in the thickness direction. 5.The semiconductor structure according to claim 4, wherein: one of the redundant structures in the redundant stack unit is arranged in the same layer as the first resonator in the resonator stack unit, the second acoustic decoupling structure being arranged between the redundant top electrode of the one redundant structure and the bottom electrode of an adjacently stacked resonator in the redundant stack unit. 6.The semiconductor structure according to claim 5, wherein: the first bottom electrode is arranged on an upper surface of the substrate; and a lower side of the redundant structure arranged in the same layer as the first resonator is not provided with an acoustic mirror. 7.The semiconductor structure according to claim 4, wherein: one of the redundant structures in the redundant stack unit is arranged in the same layer as the second resonator in the resonator stack unit, the second acoustic decoupling structure being arranged between the redundant bottom electrode of the redundant structure and the top electrode of an adjacently stacked resonator in the redundant stack unit. 8.The semiconductor structure according to any one of claims 5-7, wherein: each resonator stack unit comprises only two resonators, and the redundant stack unit comprises one redundant structure and one resonator. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 9. The semiconductor structure of any one of claims 5-7, wherein: each resonator stack unit comprises three resonators, and the redundant stack unit comprises one redundant structure and two resonators or one resonator and two redundant structures.

10. The semiconductor structure of claim 4, wherein: the redundant top electrode and the redundant bottom electrode of the redundant structure are connected to each other.

11. The semiconductor structure of claim 4, wherein: the redundant top electrode or the redundant bottom electrode of the redundant structure is electrically isolated from the outside.

12. The semiconductor structure of any one of claims 1-11, wherein: in a resonator stack unit, a first acoustic decoupling layer is arranged between the first top electrode and the second bottom electrode, and the second acoustic mirror comprises the first acoustic decoupling layer.

13. The semiconductor structure of claim 12, wherein: the electrodes on the upper and lower sides of each acoustic decoupling layer are an upper electrode and a lower electrode, respectively; the upper electrode and the lower electrode corresponding to at least one acoustic coupling layer are electrically connected.

14. The semiconductor structure of claim 13, wherein: the end of the non-electrode connecting end of the lower electrode and the end of the non-electrode connecting end of the upper electrode are connected to each other to achieve electrical connection between the upper electrode and the lower electrode; or the electrode connecting end of the lower electrode and the electrode connecting end of the upper electrode are electrically connected to achieve electrical connection between the upper electrode and the lower electrode.

15. The semiconductor structure of claim 13, wherein: the electrode connecting end of the lower electrode and the electrode connecting end of the upper electrode are electrically connected to each other, and the non-electrode connecting end of the lower electrode and the non-electrode connecting end of the upper electrode are electrically connected to each other.

16. The semiconductor structure of claim 12, wherein: the electrodes on the upper and lower sides of each acoustic decoupling layer are an upper electrode and a lower electrode, respectively; the upper electrode and the lower electrode of at least one acoustic decoupling structure are electrically isolated from each other.

17. The semiconductor structure of claim 16, wherein: the end of at least a part of the non-electrode connecting end of the upper electrode in the circumferential direction or the end of the electrode connecting end of the upper electrode is arranged on the upper surface of the piezoelectric layer below the upper electrode, and the end is located on the outside of the non-electrode connecting end of the lower electrode in the horizontal direction.

18. The semiconductor structure of claim 17, wherein: the end of a part of the non-electrode connecting end of the upper electrode in the circumferential direction or the end of the electrode connecting end of the upper electrode is arranged on the upper surface of the piezoelectric layer below the upper electrode, and the end of another part of the non-electrode connecting end of the upper electrode in the circumferential direction is located on the inside of the boundary of the corresponding acoustic decoupling layer in the horizontal direction.

19. The semiconductor structure of claim 18, wherein: the resonator stack unit comprises a first electrode layer and a second electrode layer; the first electrode layer comprises the lower electrode and a non-lower electrode layer which is electrically isolated from the non-electrode connecting end of the lower electrode and located on the outside of the non-electrode connecting end of the lower electrode; the second electrode layer comprises the upper electrode and a non-upper electrode layer which is electrically isolated from the non-electrode connecting end of the upper electrode and located on the outside of the non-electrode connecting end of the upper electrode; The electrode connection end of the upper electrode covers the non-lower electrode layer, and the non-upper electrode layer covers the electrode connection end of the lower electrode.

20. The bulk acoustic resonator assembly of claim 4 or 12, wherein: Each acoustic decoupling layer comprises a cavity.

21. A method of manufacturing a semiconductor structure, comprising: Step 1: forming at least two first structures in horizontal direction on a surface of a substrate, the at least two first structures comprising first resonator structures, each first resonator structure comprising a first bottom electrode, a first piezoelectric layer, and a first top electrode; Step 2: disposing a patterned sacrificial material layer on the at least two first structures formed in Step 1, respectively; Step 3: forming second structures on the at least two first structures of Step 2, respectively, the second structures comprising second resonator structures, the second resonator structures comprising a second bottom electrode, a second piezoelectric layer, and a second top electrode; Step 4: releasing the sacrificial material layer to form a cavity, wherein: In Step 3, the first resonator structure and the corresponding second resonator structure are stacked in thickness direction to form a resonator stack unit, and in each resonator stack unit, the sacrificial material layer is located between the first top electrode and the second bottom electrode in thickness direction of the substrate; and One of the first structure and the second structure comprises a redundant structure without resonator function, the redundant structure comprising at least a redundant piezoelectric layer, and in Step 3, one resonator structure of the other of the first structure and the second structure and the redundant structure are stacked in thickness direction to form a redundant stack unit, the redundant piezoelectric layer of the redundant stack unit is arranged in the same layer as the piezoelectric layer in the resonator stack unit, and the top electrode, the piezoelectric layer, and the bottom electrode of the resonator in the redundant stack unit are arranged in the same layer as the top electrode, the piezoelectric layer, and the bottom electrode of the resonator in the resonator stack unit, respectively.

22. The method of claim 21, wherein: The redundant structure comprises the redundant piezoelectric layer, and a redundant top electrode and / or a redundant bottom electrode, the redundant top electrode is adapted to be disposed on an upper surface of the redundant piezoelectric layer, the redundant bottom electrode is adapted to be disposed on a lower surface of the redundant piezoelectric layer, and in Step 3, the redundant electrodes of the redundant structure layer are arranged in the same layer as the corresponding electrodes of the resonator in the resonator stack unit.

23. The method of claim 22, wherein: The redundant structure comprises the redundant piezoelectric layer, the redundant top electrode, and the redundant bottom electrode; and In two stack units adjacent and stacked in horizontal direction, the top electrode of the first structure and the bottom electrode of the second structure of each stack unit are electrically connected to each other; or in two stack units adjacent and stacked in horizontal direction, the top electrode of the first structure and the bottom electrode of the second structure of each stack unit are electrically isolated from each other; or in two stack units adjacent and stacked in horizontal direction, the top electrode of the first structure and the bottom electrode of the second structure of one stack unit are electrically isolated from each other, and the top electrode of the first structure and the bottom electrode of the second structure of the other stack unit are electrically connected to each other.

24. The method of claim 23, wherein: in the at least one of the stacked units, the top electrode of the first structure and the bottom electrode of the second structure are electrically isolated from each other; in step 1, the first structure in the at least one of the stacked units comprises a first electrode layer covering the piezoelectric layer of the first structure, and the step 1 comprises a step of forming a first disconnecting structure on the first electrode layer to divide the first electrode layer into the top electrode of the first structure and a non-top electrode layer electrically isolated from a non-electrode connecting end of the top electrode of the first structure and outside the non-electrode connecting end of the top electrode of the first structure; in step 2, the sacrificial material layer also fills the first disconnecting structure; in step 3, the second structure comprises a second electrode layer covering the first electrode layer, and the step 3 comprises a step of forming a second disconnecting structure on the second electrode layer to divide the second electrode layer into the bottom electrode of the second structure and a non-bottom electrode layer electrically isolated from a non-electrode connecting end of the bottom electrode of the second structure and outside the non-electrode connecting end of the bottom electrode of the second structure; in step 4, the sacrificial material layer in the first disconnecting structure and the second disconnecting structure is removed.

25. The method of claim 23, wherein: in the at least one of the stacked units, the top electrode of the first structure and the bottom electrode of the second structure are electrically connected to each other; in step 1, the first structure in the at least one of the stacked units comprises a top electrode of the first structure covering a piezoelectric layer of the first structure; in step 3, the second structure in the at least one of the stacked units comprises a bottom electrode of the second structure covering and electrically connected to the top electrode of the first structure at an electrode connecting end and / or a non-connecting end of the bottom electrode of the second structure.

26. An electronic device comprising the semiconductor structure of any one of claims 1-20.

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