Semiconductor structure with acoustic decoupling layer, manufacturing method and electronic device

Abstract

This invention relates to a semiconductor structure, comprising: a substrate; and a filter, the filter including a plurality of resonators, the plurality of resonators being bulk acoustic wave resonators, wherein: the plurality of resonators includes at least one resonator stacking unit, the resonator stacking unit including at least a first resonator and a second resonator stacked on the same side of the substrate in the thickness direction, 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; an acoustic decoupling layer in the form of a cavity is disposed between the first top electrode and the second bottom electrode, the acoustic decoupling layer serving as the second acoustic mirror. This invention also relates to a method for manufacturing a semiconductor structure and an electronic device.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of semiconductors, and more particularly to a semiconductor structure and a method for manufacturing the same, and an electronic device having the resonator assembly. Background Technology

[0002] With the rapid development of wireless communication technology, the application of miniaturized portable terminal devices is becoming increasingly widespread, leading to a growing demand for high-performance, small-size radio frequency front-end modules and devices. In recent years, filter devices such as filters and duplexers based on thin-film acoustic resonators (FBARs) have become increasingly popular in the market. This is due to their excellent electrical performance, including low insertion loss, steep transition characteristics, high selectivity, high power capacity, and strong electrostatic discharge (ESD) resistance; and also to their small size and ease of integration.

[0003] However, in reality, there is a need to further reduce the size of filtering devices.

[0004] Furthermore, in existing designs, bulk acoustic wave resonators are combined in series and parallel to form filters. This requires multiple resonators to be formed on a substrate, with each resonator located at a different horizontal position on the substrate and connected by horizontal metal leads, such as... Figure 1 As shown, the dotted box indicates that the top electrode 104 of the resonator 100 is connected to the bottom electrode 102 of the resonator 200 through a conductive via 10. To ensure signal transmission and meet manufacturing process limitations, the connection width between 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. Generally, the total length is >5μm. This leads to the introduction of large electrical losses by the connection line, especially for high-frequency resonators. When the electrode thickness is <1000A, the insertion loss will deteriorate by more than 0.1dB. Summary of the Invention

[0005] The present invention is proposed to alleviate or solve at least one of the above-mentioned problems in the prior art.

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

[0007] Base; and

[0008] The filter includes multiple resonators, which are bulk acoustic wave resonators.

[0009] in:

[0010] The plurality of resonators includes at least one resonator stacking unit, the resonator stacking unit including at least a first resonator and a second resonator stacked on the same side of the substrate in the 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, and the second resonator including a second top electrode, a second piezoelectric layer, a second bottom electrode and a second acoustic mirror.

[0011] An acoustic decoupling layer in the form of a cavity is provided between the first top electrode and the second bottom electrode, and the acoustic decoupling layer serves as the second acoustic mirror.

[0012] Embodiments of the present invention also relate to a method for manufacturing a semiconductor structure, comprising:

[0013] Step 1: Form at least two first structures juxtaposed in a horizontal direction on the surface of a substrate, each first structure being used for a first bulk acoustic resonator, the first bulk acoustic resonator including a first acoustic mirror, a first bottom electrode, a first piezoelectric layer, and a first top electrode;

[0014] Step 2: A patterned sacrificial material layer is respectively disposed on the at least two first structures formed in step 1;

[0015] Step 3: A second structure for a second bulk acoustic resonator is formed on the at least two first structures in step 2. The second bulk acoustic resonator includes a second acoustic mirror, a second bottom electrode, a second piezoelectric layer, and a second top electrode. The first and second structures stacked in the thickness direction of the substrate form a stacked unit. In each 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.

[0016] Step 4: Release the sacrificial material layer to form a cavity, which constitutes the second acoustic mirror of the corresponding second bulk acoustic resonator.

[0017] Embodiments of the present invention also relate to an electronic device including the resonator assembly described above. Attached Figure Description

[0018] The following description and accompanying drawings will better aid in understanding these and other features and advantages of the various embodiments disclosed herein, wherein the same reference numerals in the drawings always denote the same parts, wherein:

[0019] Figure 1 A schematic cross-sectional view of the electrical connection between two adjacent bulk acoustic resonators in an existing design;

[0020] Figure 2 This is a schematic top view of a semiconductor structure according to an exemplary embodiment of the present invention;

[0021] Figure 3A 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' in the diagram;

[0022] Figure 3B For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of a bulk acoustic resonator intercepted by the B-B' line;

[0023] Figure 3C For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of a bulk acoustic resonator intercepted by the C-C' line;

[0024] Figure 3D For illustrative purposes only Figure 3A The structure relative to Figure 1 A comparison of insertion loss curves for the structures;

[0025] Figure 3E-3G Each of the different exemplary embodiments of the present invention is along Figure 2 A schematic cross-sectional view of a bulk acoustic resonator intercepted by lines A-A', A-A', and C-C'.

[0026] Figure 4A A schematic diagram of a filter that includes five body acoustic resonators;

[0027] 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;

[0028] Figure 4C 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;

[0029] Figure 5A This is a schematic diagram of a traditional dual-Rx filter, where one filter is a B3Rx filter with 5 PSA resonators and the other filter is a B1Rx filter with 5 PSA resonators.

[0030] Figure 5B A schematic diagram illustrating the arrangement of resonators in a dual Rx filter according to an exemplary embodiment of the present invention;

[0031] Figure 5C for Figure 5B The top view of the part within the dashed frame, each pentagon contains two resonators, one above the other;

[0032] Figure 5DThis is an exemplary illustration of an exemplary embodiment of the present invention. Figure 5C The cross-sectional view of the corresponding resonator, wherein the effective regions of the upper and lower resonators are acoustically isolated by a cavity;

[0033] Figure 6A A schematic diagram illustrating the arrangement of resonators in a dual Rx filter according to another exemplary embodiment of the present invention;

[0034] Figure 6B for Figure 6A The top view of the part within the dashed frame, each pentagon contains two resonators, one above the other;

[0035] Figures 7A-7G This is a schematic diagram illustrating the manufacturing process of a resonator stack unit according to an exemplary embodiment of the present invention. Detailed Implementation

[0036] The technical solution of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. In this specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the overall inventive concept of the present invention and should not be construed as a limitation thereof. These are only some embodiments of the invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0037] The reference numerals in the drawings of this invention are explained as follows:

[0038] 11,21: External leads of the top electrode of the upper resonator.

[0039] 12,22: External leads of the bottom electrode of the upper resonator.

[0040] 13,23: External leads of the top electrode of the lower resonator.

[0041] 14,24: External leads of the bottom electrode of the lower resonator.

[0042] 401: Electrode external leads. The external leads of the above electrodes are connected to the corresponding electrodes.

[0043] S: Substrate, with optional materials including single-crystal silicon, gallium nitride, gallium arsenide, sapphire, quartz, silicon carbide, diamond, etc.

[0044] 101, 201: Acoustic mirrors. Acoustic mirror 101 can be a cavity, or it can be a Bragg reflector layer or other equivalent forms. Acoustic mirror 201 is a cavity and also constitutes an acoustic decoupling layer.

[0045] 102,202: Bottom electrode, materials can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or composites or alloys of the above metals, etc.

[0046] 103, 203: Piezoelectric layer, which can be a single-crystal piezoelectric material, such as 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 film, or single-crystal lithium tantalate, etc. It can also be a polycrystalline piezoelectric material (as opposed to single-crystal, a non-single-crystal material), such as polycrystalline aluminum nitride, zinc oxide, PZT, etc. It can also be a rare earth element containing a certain atomic ratio of the above materials. The doped material can be, 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), lutetium (Lu), etc.

[0047] 104, 204: Top electrode, whose material can be the same as the bottom electrode. Materials can include molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium, or composites or alloys of the above metals. The top and bottom electrodes are generally made of the same material, but they can also be different.

[0048] 105, 205: Passivation layer, generally a dielectric material, such as silicon dioxide, aluminum nitride, silicon nitride, etc.

[0049] 106,206: Disconnected structure.

[0050] Figure 2 This is a schematic top view of a semiconductor structure according to an exemplary embodiment of the present invention. Figure 2 In the diagram, line A-A' corresponds to the cross-section through the non-electrode connection terminals of the top and bottom electrodes of the upper and lower resonators, line B-B' corresponds to the cross-section through the electrode connection terminals of the bottom and top electrodes of the lower resonator, and line C-C' corresponds to the cross-section through the electrode connection terminals of the bottom and top electrodes of the upper resonator.

[0051] Figure 3A For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of a bulk acoustic resonator obtained by intercepting the A-A' line.

[0052] Although not shown, a process layer can also be disposed on the top electrode of the resonator. This process layer can cover the top electrode and can function as a mass conditioning load or a passivation layer. The passivation layer can be made of a dielectric material, such as silicon dioxide, aluminum nitride, or silicon nitride.

[0053] In addition, Figure 3A In the structure shown, two resonators are formed at the same horizontal position on the substrate S, and the two resonators are spatially different in the vertical direction or in the thickness direction of the substrate.

[0054] As those skilled in the art will understand, three or more resonators may be stacked. For example, a resonator assembly may include a first resonator, a second resonator, and a third resonator stacked in the thickness direction. An acoustic decoupling layer 201 (a cavity in this embodiment) is provided between the top electrode 104 of the first resonator and the bottom electrode 202 of the second resonator. An additional acoustic decoupling layer is provided between the top electrode 204 of the second resonator and the bottom electrode of the third resonator. This additional acoustic decoupling layer constitutes the acoustic mirror of the third resonator.

[0055] exist Figure 3A The structure shown includes two resonators, an upper and a lower one. The effective region of the upper resonator is the overlapping area in the thickness direction of the top electrode 204, the piezoelectric layer 203, the bottom electrode 202, and the cavity 201. The lower resonator is the overlapping area in the thickness direction of the cavity 201, the top electrode 104, the piezoelectric layer 103, the bottom electrode 102, and the acoustic mirror 101.

[0056] Accordingly, when the first resonator, the second resonator, and the third resonator are stacked, 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.

[0057] exist Figure 3A In the structure shown, the upper resonator and the lower resonator are acoustically separated by the cavity 201. That is, the cavity 201 constitutes an acoustic decoupling layer between the upper and lower resonators, thereby avoiding the acoustic coupling problem that may be caused by the adjacent stacking of the two resonators.

[0058] exist Figure 3A In the structure shown, because multiple resonators are formed at the same horizontal position on the substrate S, and the spatial positions of these resonators differ in the vertical direction or in the thickness direction of the substrate, the area of ​​the filter can be greatly reduced. For example, with the same arrangement of two resonators, the area can be reduced from... Figure 1 The area P1 shown is reduced to Figure 3A The area P2 shown is shown.

[0059] like Figure 3A As shown, 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 terminals. When the bottom electrode of the upper resonator is directly connected 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 portion is relatively... Figure 1 The intermediate frequency is shortened, meaning the transmission path is shortened, reducing transmission loss. Furthermore, the electrical signal output passes through a metal with a thickness equal to the sum of the thicknesses of the top electrode of the lower resonator and the bottom electrode of the upper resonator, further reducing transmission loss. By reducing electrical loss, the insertion loss of the final filter is optimized. For example... Figure 3A As shown, 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 5μm.

[0060] 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 [a certain value]. 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.

[0061] 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 3AAfter the structure is completed, the insertion loss is improved by approximately 0.1 dB due to the reduction in electrode loss.

[0062] Figure 3B For an exemplary embodiment of the present invention, along Figure 2 A schematic cross-sectional view of a 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.

[0063] When the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically connected to each other, Figures 3A-3C In 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... Figures 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.

[0064] Figure 5D 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 5D As shown in the right-hand 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 5D 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.

[0065] 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 downwards towards the air cavity, and / or the stress of the upper resonator can be controlled to bend it upwards towards the air cavity. The top electrode of the lower resonator is concave downwards, and / or the top electrode of the upper resonator is convex upwards.

[0066] 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.

[0067] Using cavity 201 as an acoustic decoupling layer enables 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 layer of the upper and / or lower resonator), for example... Figures 3A-3C In the case of the structures shown in 4B-4C and 5D, the overall structure is stable and reliable and the processing technology is simple.

[0068] 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.

[0069] exist Figures 3A-3C In the accompanying drawings 4B-4C, 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 5D The left-side view.

[0070] 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.

[0071] Figure 3FFor an exemplary embodiment of the present invention, along Figure 2 The schematic cross-sectional view of the bulk acoustic resonator taken by line A-A' 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).

[0072] 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 5D The left-side cross-sectional view. The top electrode 104 is located in the first electrode layer. Figure 5D In the left-hand view, the first electrode layer includes a top electrode 104 and a non-top electrode layer (i.e., the portion to the left of the disconnect structure 106 in Figure 5) located outside the non-electrode connection terminal of the top electrode 104, electrically isolated from it via a disconnect structure 106. Figure 5D In the middle, the bottom electrode 202 is located in the second electrode layer, such as Figure 5D 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 (i.e., the right-hand portion of the disconnect structure 206 in Figure 5), electrically isolated from the non-electrode connection terminal of the bottom electrode 202 via a disconnect structure 206. Figure 5D 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.

[0073] 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. 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.

[0074] In a further embodiment, to improve process stability, in Figure 4B In this example, the series resonator Se1 is placed above a non-functional material 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 material with the height of a parallel resonator" corresponds to a redundant resonator. For example... Figure 4B As shown, a redundant resonator is arranged below the series resonator Se1 on the left side. This redundant resonator 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 resonator layer are arranged in the same layer as the top electrode 104, piezoelectric layer 103, and bottom electrode 102, respectively. However, as a redundant resonator, it does not have the function of a resonator, for example, in... Figure 4B In the diagram shown, the redundant resonator does not have an acoustic mirror cavity below it. Alternatively, the redundant resonator 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.

[0075] exist Figure 4B In the resonator arrangement of the single filter shown, the characteristics of the stacked resonator are fully utilized, and the bottom electrode of the upper resonator is interconnected with the top electrode of the lower resonator.

[0076] exist Figure 4B In the diagram, 401 represents the external lead of the electrode, for example, in... Figure 4B On the right side, the external lead 401 is electrically connected to both 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 merely exemplary, and other methods can also be used to achieve the electrical connection of the resonator electrodes.

[0077] Figure 4C 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 4C and Figure 4B The difference is that, in Figure 4C In this case, the series resonator Se1 is directly mounted on the substrate without any redundant resonators.

[0078] Figure 5AThis diagram illustrates a traditional dual-Rx filter. One filter is a B3Rx filter with five PAS resonators: three series resonators B3-Se1 to B3-Se3 and two parallel resonators B3-Sh1 to B3-Sh2. The other filter is a B1Rx filter with five PAS resonators: three series resonators B1-Se1 to B1-Se3 and two parallel resonators B1-Sh1 to B1-Sh2. The series and parallel resonators have different resonant frequencies, thus forming a bandpass filter. Filters B1Rx and B3Rx have different diaphragm thicknesses, and therefore different resonant frequencies.

[0079] Figure 5B This is a schematic diagram illustrating the arrangement of resonators in a dual Rx filter according to an exemplary embodiment of the present invention. The resonators are stacked in pairs, thereby reducing the planar area of ​​the filter.

[0080] Figure 5C for Figure 5B The top view of the portion within the dashed frame shows that each pentagon contains two resonators, one above the other. Figure 5C In the diagram, the pentagon on the left represents the B3-Se3 resonator and the B1-Se1 resonator, where B3-Se3 and B1-Se1 are not electrically connected; the pentagon on the right represents the B1-Se2 resonator and the B1-Sh1 resonator, where B1-Se2 and B1-Sh1 are electrically connected.

[0081] Figure 5D This is an exemplary illustration of an exemplary embodiment of the present invention. Figure 5C The cross-sectional diagram of the corresponding resonator shows that the effective regions of the upper and lower resonators are acoustically isolated by a cavity.

[0082] exist Figure 5D In the middle, 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 region, such as... Figure 5D As shown on the right; 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 region, such as... Figure 5D As shown in the left-hand view. This has already been explained. Figure 5D The electrode connections of the upper and lower resonators of the stacked resonator on the left side, and Figure 5D The electrode connections of the upper and lower resonators of the stacked resonator on the right side are not described here.

[0083] Figure 5D The illustrated embodiments are relative to Figure 4BIn the embodiment, an additional layer of resonators or resonator stacking units is used in the resonator arrangement, where the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically isolated. Furthermore, because the resonant frequencies of filters B1 and B3 differ by approximately 300MHz, the thicknesses of the film layers in filters B1 and B3 will be different. That is, in filters B1 and B3, the upper and lower layers will have two different film layer stacking thicknesses. For example, for... Figure 5D Regarding the top electrode of the upper and middle resonators, the film thickness in the filter B3 on the left side is greater than the film thickness in the filter B1 on the right side.

[0084] Figure 6A A schematic diagram illustrating the arrangement of resonators in a dual Rx filter according to another exemplary embodiment of the present invention. Figure 6B for Figure 6A The top view of the portion within the dashed frame shows that each pentagon contains two resonators, one above the other.

[0085] Figures 6A-6B The illustrated embodiment differs from the one shown. Figures 5A-5D The middle layer will mix and match all resonators of the dual Rx filter, meaning the lower-level resonator could be either a resonator from filter B3Rx or a resonator from filter B1Rx. Figures 6A-6B In the illustrated embodiment, the lower resonators are all resonators of filter B1Rx, and the upper resonators are all resonators of filter B3Rx.

[0086] exist Figures 5A-5D In one embodiment, the scheme can minimize the overall area of ​​the filter's resonators.

[0087] The thicknesses of the films in filters B1 and B3 will differ; that is, at least one layer in the bottom electrode, piezoelectric layer, and top electrode of filter B1 will have a thickness different from the corresponding film layer in filter B3. To achieve this, taking the top electrode as an example, the thickness of the top electrode in filter B3 is 4000 Å, while the thickness of the top electrode in filter B1 is 3500 Å. During fabrication, a 500 Å top electrode layer needs to be deposited first, and then the 500 Å top electrode at filter B1 needs to be removed (photolithography + etching). Then, a 3500 Å top electrode layer is deposited. Finally, photolithography and etching are used to retain the top electrode patterns of both filters B1 and B3, completing the fabrication of the different top electrodes. The two thicknesses of the top electrodes require two photolithography and etching processes. Therefore... Figures 5A-5D The fabrication of the bottom electrode, piezoelectric layer, and top electrode shown requires 4-6 steps of photolithography and etching.

[0088] and Figures 6A-6BIn the structure shown, the lower resonator needs to be a thick stacked resonator (i.e., all resonators have the same main frequency, and the frequency of individual resonators is fine-tuned by mass load), such as the resonator of filter B1Rx, and the upper resonator needs to be another type of thick stacked resonator, such as the resonator of filter B3Rx. Figures 6A-6B The illustrated embodiment is compared to Figures 5A-5D The embodiments shown can simplify the process complexity (reduce 1-3 steps of photolithography and etching) and reduce manufacturing costs.

[0089] like Figure 6A As shown, in this scheme, the upper and lower resonators are not electrically connected in principle. Figure 6B In this configuration, each vertical direction contains two resonators and four electrical leads, with filter B3Rx having no electrical connection to filter B1Rx.

[0090] The following is a detailed explanation. Figures 5A-5D The overall area in the embodiment shown is smaller than Figures 6A-6B The overall area in the illustrated embodiment.

[0091] Since the frequency of filter B1Rx is higher than that of filter B3Rx, the 50-ohm area of ​​a single resonator in filter B1Rx is smaller than that in filter B3Rx. In one design, the area of ​​a single resonator in filter B1Rx is approximately 16000 μm. 2 (16Kμm 2 The area of ​​a single resonator in the B3Rx filter is approximately 18 kμm. 2 When using Figures 6A-6B The layout shown does not consider the area of ​​outer perimeter components such as lead wires; the total area is approximately 18K x 5 = 90K. When using... Figures 5A-5D The layout shown does not consider the area of ​​outer perimeter components such as leads; the total area is approximately 16K x 2 + 18K + 18K x 2 = 86K (μm). 2 The first term represents a resonator where both the upper and lower resonators are filters B1Rx; the second term represents a resonator where one upper and lower resonator is a filter B1Rx and the other is a filter B3Rx; and the third term represents a resonator where both the upper and lower resonators are filters B3Rx. The final result... Figures 5A-5D The illustrated embodiment is more Figures 6A-6B The illustrated embodiment has a smaller area. This area difference will be more pronounced for two frequency bands with significantly different resonator areas, but... Figures 5A-5D The illustrated embodiment is also more technologically advanced than... Figures 6A-6B The illustrated embodiment is more complex. Therefore, for different applications, the implementation scheme should be selected based on the primary concern (area or cost).

[0092] In the above embodiments, the filter includes an odd number of resonators, but the invention is not limited to this and may also include an even number of resonators. When the filter includes an even number of resonators, if two resonators are stacked to form a resonator stacking unit, the problem of needing to set up the aforementioned redundant resonators does not exist. However, depending on the different numbers of resonators in the resonator stacking unit, the problem of setting up redundant resonators may still exist. Furthermore, when both filters include an even number of resonators, for example... Figure 5B and Figure 6A The arrangement shown is as follows.

[0093] In the above embodiments, the stacked resonator unit includes two resonators, but the present invention is not limited to this and may include more resonators. For example, when there are three resonators in the stacked resonator unit, the number of resonators in each filter may be 3n+1, where n is the number of resonator stacked units contained in the filter. Then, the remaining three resonators in the three filters can also form a hybrid stacked unit. Optionally, the number of resonators in some filters may be 3n+1, while the number of resonators in other filters may be 3n+2. The remaining one resonator and two resonators in each of the two filters can form a hybrid stacked unit.

[0094] for Figure 5B In this way, there can also be multiple pairs of mixed rows (in each pair of mixed rows, the resonators of different filters constitute a resonator stacking unit).

[0095] Furthermore, a single filter or filter bank may consist of only one resonator stack unit or multiple resonator stack units.

[0096] In the above embodiments, for stacked resonators or resonator stacking units, there are two types: one where the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically connected to each other, and the other where the bottom electrode of the upper resonator and the top electrode of the lower resonator are electrically isolated from each other. See below for further details. Figures 7A-7G For illustrative purposes only Figure 5D The diagram shows the manufacturing process of the structure, where the left side of each diagram corresponds to the bottom electrode of the upper resonator and the top electrode of the lower resonator being electrically isolated from each other, while the right side corresponds to the bottom electrode of the upper resonator and the top electrode of the lower resonator being electrically connected to each other.

[0097] Step 1: As Figure 7A As shown, the lower resonator is fabricated using a conventional FBAR process. The lower resonator includes a recess corresponding to the acoustic mirror cavity 101, in which a sacrificial material is disposed; a bottom electrode 102; a piezoelectric layer 103; a top electrode 104; and a passivation layer 105. If understood, the passivation layer 105 may be omitted. Furthermore, Figure 7AThe acoustic mirror in the image can also take other forms. See also Figure 7A The top electrode 104 is covered with a piezoelectric layer 103.

[0098] Step 2: For electrically disconnected upper and lower resonators, the external leads of the top electrode 104 of the lower resonator and the bottom electrode 202 of the upper resonator need to be disconnected. For example... Figure 7B As shown, the disconnected structure 106 can be fabricated by photolithography and etching. The disconnected structure corresponds to an opening or a through hole (if understood, a through hole is a strip-shaped through hole).

[0099] Step 3: As Figure 7C As shown, a sacrificial layer (such as PSG (phosphosilicate glass), amorphous silicon, BSG (borosilicate glass), BPSG (borophosphosilicate glass), USG (US silicate glass), etc.) is deposited on the structure formed in step 2. To improve the quality of the film layer on the subsequent resonator, the deposited sacrificial material layer can be planarized using CMP (chemical mechanical polishing). Figure 7C In the middle, as shown on its left, sacrificial material fills the broken structure 106.

[0100] Step 4: As Figure 7D As shown, 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 301, which will eventually be removed to form a cavity 201 that acoustically isolates the upper and lower resonators.

[0101] Step 5: As Figure 7E As shown, in Figure 7D 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 7E 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 7E The structure shown is in Figure 7E 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 7E 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 7E 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.

[0102] Step 6: As Figure 7F As shown, in Figure 7E On the structure shown, the piezoelectric layer 203, top electrode 204, and passivation layer 205 of the upper resonator are deposited and patterned.

[0103] Step 7: As Figure 7G 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.

[0104] It should be noted that, in this invention, each numerical range, except where explicitly stated not to include endpoint values, can be either an endpoint value or the median of the numerical range, all of which are within the protection scope of this invention.

[0105] In this invention, "upper" and "lower" are relative to the bottom surface of the resonator's base. For a component, the side closer to the bottom surface is the lower side, and the side farther from the bottom surface is the upper side.

[0106] In this invention, "inner" and "outer" refer to the center of the effective region of the resonator (i.e., the center of the effective region) in the lateral or radial direction. The side or end of a component closer to the center of the effective region is called the inner side or inner end, while the side or end of the component farther from the center of the effective region is called the outer side or outer end. For a reference position, being inside the position means being between that position and the center of the effective region in the lateral or radial direction, while being outside the position means being farther from the center of the effective region in the lateral or radial direction than that position.

[0107] As those skilled in the art will understand, the bulk acoustic resonator according to the present invention can be used to form filters or electronic devices. These electronic devices include, but are not limited to, intermediate products such as RF front-ends and filtering / amplifying modules, as well as terminal products such as mobile phones, Wi-Fi devices, and drones.

[0108] Based on the above, the present invention proposes the following technical solution:

[0109] 1. A semiconductor structure, comprising:

[0110] Base; and

[0111] The filter includes multiple resonators, which are bulk acoustic wave resonators.

[0112] in:

[0113] The plurality of resonators includes at least one resonator stacking unit, the resonator stacking unit including at least a first resonator and a second resonator stacked on the same side of the substrate in the 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, and the second resonator including a second top electrode, a second piezoelectric layer, a second bottom electrode and a second acoustic mirror.

[0114] An acoustic decoupling layer in the form of a cavity is provided between the first top electrode and the second bottom electrode, and the acoustic decoupling layer serves as the second acoustic mirror.

[0115] 2. The semiconductor structure according to 1, wherein:

[0116] The filter includes a first filter and a second filter, and the plurality of resonators belong to the first filter and the second filter respectively;

[0117] At least one resonator of the first filter and at least one resonator of the second filter are electrically isolated from each other in such a way that one resonator is on top and the other resonator is on the bottom, and constitute at least one resonator stacking unit.

[0118] 3. According to the semiconductor structure described in 2, wherein:

[0119] Each resonator stacking unit includes two resonators. The number of resonator stacking units included in the semiconductor structure is (m+n) / 2, where m is the number of resonators participating in the stacking in the first filter, n is the number of resonators participating in the stacking in the second filter, and both m and n are odd numbers.

[0120] 4. According to the semiconductor structure described in 3, wherein:

[0121] The first piezoelectric layer of the first resonator in all resonator stack units is the piezoelectric layer of the resonator of the first filter; and

[0122] The second piezoelectric layer of the second resonator in all resonator stack units is the piezoelectric layer of the resonator of the second filter.

[0123] 5. According to the semiconductor structure described in 3, wherein:

[0124] The (m-1) resonators in the first filter form (m-1) / 2 resonator stacking units, and the (n-1) resonators in the second filter form (n-1) / 2 resonator stacking units; and

[0125] The remaining resonator in the first filter and the remaining resonator in the second filter are electrically isolated from each other with one resonator on top and the other on the bottom, forming a resonator hybrid stacking unit.

[0126] 6. The semiconductor structure according to 1, wherein:

[0127] The filter includes a first filter and a second filter, and the plurality of resonators belong to the first filter and the second filter respectively. The first filter includes m resonators, and the second filter includes n resonators, where m and n are both even numbers; and

[0128] The m resonators in the first filter form m / 2 resonator stacking units, and the n resonators in the second filter form n / 2 resonator stacking units; or the m+n resonators form (m+n) / 2 resonator stacking units, and the first piezoelectric layer of the first resonator in all resonator stacking units is the piezoelectric layer of the resonator in the first filter, and the second piezoelectric layer of the second resonator in all resonator stacking units is the piezoelectric layer of the resonator in the second filter.

[0129] 7. The semiconductor structure according to 1, wherein:

[0130] The filter includes a single filter.

[0131] The single filter comprises m individual acoustic resonators, where m is a natural number greater than 1.

[0132] 8. According to the semiconductor structure described in 7, wherein:

[0133] m is an odd number;

[0134] The plurality of resonators includes (m-1) / 2 resonator stacking units.

[0135] 9. According to the semiconductor structure described in 8, wherein:

[0136] The semiconductor structure further includes a redundant resonator layer, which is stacked with one remaining resonator among the m resonators; and

[0137] The redundant resonator layer includes 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 resonator layer are arranged in the same layer as the top electrode, piezoelectric layer, and bottom electrode of the first resonator or the second resonator in the resonator stacking unit.

[0138] 10. The semiconductor structure according to any one of 2-3, 5-9, wherein:

[0139] The first top electrode and the second bottom electrode are electrically connected to each other.

[0140] 11. According to the semiconductor structure described in 10, wherein:

[0141] The end of the non-electrode connection of the first top electrode is connected to the end of the non-electrode connection of the second bottom electrode.

[0142] 12. According to the semiconductor structure described in 10, wherein:

[0143] The electrode connection terminal of the first top electrode is electrically connected to the electrode connection terminal of the second bottom electrode.

[0144] 13. According to the semiconductor structure described in 10, wherein:

[0145] The electrode connection terminal of the first top electrode is electrically connected to the electrode connection terminal of the second bottom electrode, and the non-electrode connection terminal of the first top electrode is electrically connected to the non-electrode connection terminal of the second bottom electrode.

[0146] 14. The semiconductor structure according to any one of 1-9, wherein:

[0147] The first top electrode and the second bottom electrode are electrically isolated from each other.

[0148] 15. According to the semiconductor structure described in 14, wherein:

[0149] At least a portion of the non-electrode connection end of the second bottom electrode in the circumferential direction or the end of the electrode connection end of the second bottom electrode is disposed on the upper surface of the first piezoelectric layer, and the end is located outside the non-electrode connection end of the first top electrode in the horizontal direction.

[0150] 16. According to the semiconductor structure described in 15, wherein:

[0151] A portion of the non-electrode connection end of the second bottom electrode in the circumferential direction or the end of the electrode connection end of the second bottom electrode is disposed on the upper surface of the first piezoelectric layer, and the other portion of the non-electrode connection end of the second bottom electrode in the circumferential direction is located inside the boundary of the acoustic decoupling layer in the horizontal direction.

[0152] 17. According to the semiconductor structure described in 16, wherein:

[0153] The resonator stacking unit includes a first electrode layer and a second electrode layer;

[0154] The first electrode layer includes a first top electrode and a non-top electrode layer that is electrically isolated from the non-electrode connection terminal of the first top electrode and located outside the non-electrode connection terminal of the first top electrode;

[0155] The second electrode layer includes a second bottom electrode and a non-bottom electrode layer that is electrically isolated from the non-electrode connection terminal of the second bottom electrode and located outside the non-electrode connection terminal of the second bottom electrode;

[0156] The electrode connection end of the second bottom electrode covers the non-top electrode layer, and the non-bottom electrode layer covers the electrode connection end of the first top electrode.

[0157] 18. According to the semiconductor structure described in 2, wherein:

[0158] The first filter includes an M1 individual acoustic resonator, and the second filter includes an M2 individual acoustic resonator, where M1 = 3p + 1 and M2 = 3q + 2, and p and q are natural numbers.

[0159] The 3p resonators in the first filter form p resonator stacking units, and the 3q resonators in the second filter form q resonator stacking units. Each resonator stacking unit includes 3 stacked resonators.

[0160] The remaining resonator of the first filter and the remaining two resonators of the second filter are stacked together to form a hybrid stacking unit.

[0161] 19. A method for manufacturing a semiconductor structure, comprising:

[0162] Step 1: Form at least two first structures juxtaposed in a horizontal direction on the surface of a substrate, each first structure being used for a first bulk acoustic resonator, the first bulk acoustic resonator including a first acoustic mirror, a first bottom electrode, a first piezoelectric layer, and a first top electrode;

[0163] Step 2: A patterned sacrificial material layer is respectively disposed on the at least two first structures formed in step 1;

[0164] Step 3: A second structure for a second bulk acoustic resonator is formed on the at least two first structures in step 2. The second bulk acoustic resonator includes a second acoustic mirror, a second bottom electrode, a second piezoelectric layer, and a second top electrode. The first and second structures stacked in the thickness direction of the substrate form a stacked unit. In each 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.

[0165] Step 4: Release the sacrificial material layer to form a cavity, which constitutes the second acoustic mirror of the corresponding second bulk acoustic resonator.

[0166] 20. According to the method described in 19, wherein:

[0167] In two stacked units placed adjacent to each other in the horizontal direction, the first top electrode and the second bottom electrode of each stacked unit are electrically connected to each other; or

[0168] In two stacked units placed adjacent to each other in the horizontal direction, the first top electrode and the second bottom electrode of each stacked unit are electrically isolated from each other; or

[0169] In two stacked units placed side by side in the horizontal direction, the first top electrode and the second bottom electrode of one stacked unit are electrically isolated from each other, while the first top electrode and the second bottom electrode of the other stacked unit are electrically connected to each other.

[0170] 21. According to the method described in 20, wherein:

[0171] In two stacked units placed side by side in the horizontal direction, the first top electrode and the second bottom electrode in at least one stacked unit are electrically isolated from each other;

[0172] In step 1, the first structure in at least one stacked unit includes a first electrode layer covering the first piezoelectric layer. Step 1 includes the steps of: forming a first disconnect structure on the first electrode layer to divide the first electrode layer into a first top electrode and a non-top electrode layer that is electrically isolated from the non-electrode connection terminal of the first top electrode and located outside the non-electrode connection terminal of the first top electrode.

[0173] In step 2, the sacrificial material layer also fills the first disconnected structure;

[0174] In step 3, the second structure includes a second electrode layer covering the first electrode layer. Step 3 includes the steps of: forming a second disconnect structure on the second electrode layer to divide the second electrode layer into a second bottom electrode and a non-bottom electrode layer that is electrically isolated from the non-electrode connection terminal of the second bottom electrode and located outside the non-electrode connection terminal of the second bottom electrode.

[0175] In step 4, the sacrificial material layer in the first disconnection structure and the second disconnection structure is removed.

[0176] 22. According to the method described in 20, wherein:

[0177] In two stacked units placed side by side in the horizontal direction, the first top electrode and the second bottom electrode in at least one stacked unit are electrically connected to each other.

[0178] In step 1, the first structure in at least one stacked unit includes a first top electrode covering the first piezoelectric layer;

[0179] In step 3, the second structural layer in at least one stacked unit includes a second bottom electrode, which covers and is electrically connected to the first top electrode at the electrode connection end and / or non-connection end of the second bottom electrode.

[0180] 23. An electronic device comprising a semiconductor structure according to any one of 1-18.

[0181] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that variations may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A semiconductor structure, comprising: a substrate; and a filter comprising a plurality of resonators, the plurality of resonators being bulk acoustic wave resonators, wherein: the plurality of resonators comprises at least one resonator stack unit, the resonator stack unit comprising at least a first resonator and a second resonator stacked on a same 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; an acoustic decoupling layer in the form of a cavity is provided between the first top electrode and the second bottom electrode, the acoustic decoupling layer acting as the second acoustic mirror; wherein: the filter comprises a first filter and a second filter, the plurality of resonators belonging to the first filter and the second filter; at least one resonator of the first filter and at least one resonator of the second filter are provided in an electrically isolated manner from each other with one resonator on top of the other and form at least one resonator stack unit. 2.The semiconductor structure of claim 1, wherein: each resonator stack unit comprises two resonators, the semiconductor structure comprises (m+n) / 2 resonator stack units, where m is the number of resonators of the first filter participating in stacking, n is the number of resonators of the second filter participating in stacking, and m and n are both odd numbers. 3.The semiconductor structure of claim 2, wherein: the first piezoelectric layer of the first resonator in all resonator stack units is the piezoelectric layer of the resonator of the first filter; and the second piezoelectric layer of the second resonator in all resonator stack units is the piezoelectric layer of the resonator of the second filter. 4.The semiconductor structure of claim 2, wherein: (m-1) resonators in the first filter form (m-1) / 2 resonator stack units, (n-1) resonators in the second filter form (n-1) / 2 resonator stack units; and the remaining one resonator in the first filter and the remaining one resonator in the second filter are provided in an electrically isolated manner from each other with one resonator on top of the other and form one resonator hybrid stack unit. 5.The semiconductor structure of claim 1, wherein: the filter comprises a first filter and a second filter, the plurality of resonators belonging to the first filter and the second filter, the first filter comprising m resonators, the second filter comprising n resonators, and m and n are both even numbers; and m resonators in the first filter form m / 2 resonator stack units, n resonators in the second filter form n / 2 resonator stack units; or (m+n) resonators form (m+n) / 2 resonator stack units, and the first piezoelectric layer of the first resonator in all resonator stack units is the piezoelectric layer of the resonator of the first filter, and the second piezoelectric layer of the second resonator in all resonator stack units is the piezoelectric layer of the resonator of the second filter. ​ ​ 6. The semiconductor structure of claim 1, wherein: the filter comprises a single filter comprising m individual acoustic wave resonators, m being a natural number greater than 1.

7. The semiconductor structure of claim 6, wherein: m is an odd number; the plurality of resonators comprises (m-1) / 2 resonator stack units.

8. The semiconductor structure of claim 7, wherein: the semiconductor structure further comprises a redundant resonator layer arranged in a stack with a remaining one of the m individual acoustic wave resonators; and the redundant resonator layer comprises a redundant top electrode, a redundant piezoelectric layer, and a redundant bottom electrode, the redundant top electrode, the redundant piezoelectric layer, and the redundant bottom electrode of the redundant resonator layer being arranged in the same layer as the top electrode, the piezoelectric layer, and the bottom electrode of the first resonator or the second resonator in the resonator stack unit, respectively.

9. The semiconductor structure of any one of claims 1-2, 4-8, wherein: the first top electrode and the second bottom electrode are electrically connected to each other.

10. The semiconductor structure of claim 9, wherein: an end portion of the non-electrode-connection end of the first top electrode and an end portion of the non-electrode-connection end of the second bottom electrode are in contact with each other.

11. The semiconductor structure of claim 9, wherein: the electrode-connection end of the first top electrode and the electrode-connection end of the second bottom electrode are electrically connected to each other.

12. The semiconductor structure of claim 9, wherein: the electrode-connection end of the first top electrode and the electrode-connection end of the second bottom electrode are electrically connected to each other, and the non-electrode-connection end of the first top electrode and the non-electrode-connection end of the second bottom electrode are electrically connected to each other.

13. The semiconductor structure of any one of claims 1-8, wherein: the first top electrode and the second bottom electrode are electrically isolated from each other.

14. The semiconductor structure of claim 13, wherein: an end portion of at least a portion of the non-electrode-connection end of the second bottom electrode in a circumferential direction or an end portion of the electrode-connection end of the second bottom electrode is disposed on the upper surface of the first piezoelectric layer, and the end portion is located on an outer side of the non-electrode-connection end of the first top electrode in a horizontal direction.

15. The semiconductor structure of claim 14, wherein: an end portion of a portion of the non-electrode-connection end of the second bottom electrode in a circumferential direction or an end portion of the electrode-connection end of the second bottom electrode is disposed on the upper surface of the first piezoelectric layer, and an end portion of another portion of the non-electrode-connection end of the second bottom electrode in the circumferential direction is located on an inner side of the boundary of the acoustic decoupling layer in the horizontal direction.

16. The semiconductor structure of claim 15, wherein: the resonator stack unit comprises a first electrode layer and a second electrode layer; the first electrode layer comprises the first top electrode and a non-top electrode layer electrically isolated from the non-electrode-connection end of the first top electrode and located on an outer side of the non-electrode-connection end of the first top electrode; the second electrode layer comprises the second bottom electrode and a non-bottom electrode layer electrically isolated from the non-electrode-connection end of the second bottom electrode and located on an outer side of the non-electrode-connection end of the second bottom electrode; The electrode connecting end of the second bottom electrode covers the non-top electrode layer, and the non-bottom electrode layer covers the electrode connecting end of the first top electrode. 17.The semiconductor structure of claim 1, wherein: The first filter comprises M1 individual acoustic wave resonators, and the second filter comprises M2 individual acoustic wave resonators, M1=3p+1, and M2=3q+2, where p and q are natural numbers; The 3p resonators in the first filter form p resonator stack units, and the 3q resonators in the second filter form q resonator stack units, each of which comprises 3 stacked resonators; The remaining one resonator of the first filter and the remaining two resonators of the second filter are stacked with each other to form a mixed stack unit. 18.A method for manufacturing a semiconductor structure, comprising: Step 1: forming at least two first structures in horizontal direction on the surface of the substrate, each of which is used for a first bulk acoustic wave resonator comprising a first acoustic mirror, a first bottom electrode, a first piezoelectric layer, and a first top electrode; Step 2: disposing a patterned sacrificial material layer on each of the at least two first structures formed in step 1; Step 3: forming a second structure for a second bulk acoustic wave resonator on each of the at least two first structures in step 2, the second bulk acoustic wave resonator comprising a second acoustic mirror, a second bottom electrode, a second piezoelectric layer, and a second top electrode, the first structure and the second structure in the thickness direction of the substrate form a stack unit, and in each 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; Step 4: releasing the sacrificial material layer to form a cavity, which constitutes the second acoustic mirror of the corresponding second bulk acoustic wave resonator; The semiconductor structure comprises a filter, the filter comprises a plurality of resonators, the filter comprises a first filter and a second filter, and the plurality of resonators belong to the first filter and the second filter; At least one resonator of the first filter and at least one resonator of the second filter are arranged in a manner that one resonator is on top and the other resonator is on bottom, and are electrically isolated from each other to form at least one resonator stack unit. 19.The method of claim 18, wherein: In two stack units adjacent and juxtaposed in the horizontal direction, the first top electrode and the second bottom electrode of each stack unit are electrically connected to each other; or In two stack units adjacent and juxtaposed in the horizontal direction, the first top electrode and the second bottom electrode of each stack unit are electrically isolated from each other; or In two stack units adjacent and juxtaposed in the horizontal direction, the first top electrode and the second bottom electrode of one stack unit are electrically isolated from each other, and the first top electrode and the second bottom electrode of the other stack unit are electrically connected to each other. 20.The method of claim 19, wherein: In two stack units adjacent and juxtaposed in the horizontal direction, the first top electrode and the second bottom electrode in at least one stack unit are electrically isolated from each other; ​ In step 1, the first structure in the at least one stacked unit comprises a first electrode layer covering the first piezoelectric layer, the step 1 comprising the step of forming a first disconnect structure on the first electrode layer to divide the first electrode layer into a first top electrode and a non-top electrode layer electrically isolated from a non-electrode connecting end of the first top electrode and outside the non-electrode connecting end of the first top electrode; In step 2, the sacrificial material layer also fills the first disconnect structure; In step 3, the second structure comprises a second electrode layer covering the first electrode layer, the step 3 comprising the step of forming a second disconnect structure on the second electrode layer to divide the second electrode layer into a second bottom electrode and a non-bottom electrode layer electrically isolated from a non-electrode connecting end of the second bottom electrode and outside the non-electrode connecting end of the second bottom electrode; In step 4, the sacrificial material layer in the first disconnect structure and the second disconnect structure is removed.

21. The method of claim 19, wherein: In two horizontally adjacent and juxtaposed stacked units, the first top electrode and the second bottom electrode in the at least one stacked unit are electrically connected to each other; In step 1, the first structure in the at least one stacked unit comprises a first top electrode covering the first piezoelectric layer; In step 3, the second structure layer in the at least one stacked unit comprises a second bottom electrode, the second bottom electrode covering and electrically connected to the first top electrode at an electrode connecting end and / or a non-connecting end of the second bottom electrode.

22. An electronic device comprising the semiconductor structure of any one of claims 1-17.

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