Thin film surface acoustic wave resonator and method for manufacturing the same

Abstract

The present invention relates to a thin film surface acoustic wave resonator and a manufacturing method thereof, wherein the thin film surface acoustic wave resonator comprises: a first interdigital electrode having a plurality of first interdigits, a second interdigital electrode having a plurality of second interdigits, the first interdigits and the second interdigits being arranged at intervals; a first connecting line, at least located at one end of the first interdigit, electrically connected to the first interdigit; a second connecting line, at least located at one end of the second interdigit, electrically connected to the second interdigit; a first gap is provided between the first connecting line and the first interdigit, the first connecting line and the first interdigit are connected via a first interconnecting electrode spanning the first gap; and / or a second gap is provided between the second connecting line and the second interdigit, the second connecting line and the second interdigit are connected via a second interconnecting electrode spanning the second gap. The present invention separates the interdigits from the corresponding connecting lines via the corresponding gaps, so as to reduce the vibration obstruction of the interdigits by the metal structure outside the interdigits, and at the same time avoids causing disturbance to the surface acoustic waves at the ends of the interdigits.

Description

Technical Field

[0001] The invention relates to the field of semiconductor device manufacturing, and in particular to a thin film surface acoustic wave resonator and a manufacturing method thereof. Background Art

[0002] Since the development of analog RF communication technology in the early 1990s, RF front-end modules have gradually become the core components of communication equipment. Among all RF front-end modules, filters have become the components with the strongest growth momentum and the greatest development prospects. With the rapid development of wireless communication technology and the increasing maturity of 5G communication protocols, the market has also put forward more stringent standards for the performance of RF filters in all aspects. The performance of the filter is determined by the resonator units that make up the filter. SAW devices (surface acoustic wave devices) have the characteristics of small size, low insertion loss, large out-of-band suppression, high quality factor, high operating frequency, large power capacity and good anti-static shock ability, making them one of the most suitable filters for 5G applications. SAW devices (surface acoustic wave devices) are circuit elements that convert electrical signals into surface waves and perform signal processing. They are widely used as filters, resonators, etc.

[0003] Usually, the surface acoustic wave resonator is made of two interdigital transducers on the polished surface of the substrate material with piezoelectric properties, which serve as the transmitting transducer and the receiving transducer respectively. The transmitting transducer converts the RF signal into a surface acoustic wave, which propagates on the surface of the substrate. After a certain delay, the receiving transducer converts the acoustic signal into an electrical signal for output. The filtering process is realized in the piezoelectric conversion from electricity to sound and from sound to electricity.

[0004] However, the surface acoustic wave resonators currently manufactured have the ends of the interdigitated electrodes electrically connected by traditional metal leads, which easily cause disturbances to the surface acoustic waves at the ends of the interdigitated electrodes, making it impossible to further improve the quality factor (Q) and the yield rate low, and therefore cannot meet the needs of high-performance RF systems. Summary of the invention

[0005] The object of the present invention is to provide a thin film surface acoustic wave resonator and a manufacturing method thereof, which can improve the quality factor of the thin film surface acoustic wave resonator and thus improve the device performance.

[0006] In order to achieve the above object, the present invention provides a thin film surface acoustic wave resonator, comprising:

[0007] A first interdigital electrode having a plurality of first interdigital fingers and a second interdigital electrode having a plurality of second interdigital fingers, wherein the first interdigital fingers are spaced apart from the second interdigital fingers;

[0008] A first connecting line, located at least at one end of the first interdigital finger and electrically connected to the first interdigital finger;

[0009] A second connecting line, located at least at one end of the second interdigital finger and electrically connected to the second interdigital finger;

[0010] There is a first gap between the first connecting line and the first interdigital finger, and the first connecting line and the first interdigital finger are connected via a first interconnection electrode spanning the first gap;

[0011] and / or,

[0012] There is a second gap between the second connecting line and the second interdigital finger, and the second connecting line and the second interdigital finger are connected via a second interconnection electrode spanning the second gap.

[0013] The present invention also provides a method for manufacturing a thin film surface acoustic wave resonator, comprising:

[0014] providing a piezoelectric layer;

[0015] A first interdigital electrode having a plurality of first interdigital fingers and a second interdigital electrode having a plurality of second interdigital fingers are formed on the piezoelectric layer, wherein the first interdigital fingers and the second interdigital fingers are arranged at intervals;

[0016] forming a first connecting line, wherein the first connecting line is formed at least at one end of the first interdigitated finger and has a first gap between the first connecting line and the first interdigitated finger;

[0017] and / or,

[0018] forming a second connecting line, wherein the second connecting line is formed at least at one end of the second interdigital finger and has a second gap between the second interdigital finger and the second interdigital finger;

[0019] forming a first interconnection electrode, the first interconnection electrode spanning the first gap and electrically connecting the first interdigital finger and the first connection line;

[0020] A second interconnection electrode is formed, which spans the second gap and electrically connects the second interdigitated finger and the second connection line.

[0021] The beneficial effects of the thin film surface acoustic wave resonator of the present invention are:

[0022] A first connecting line is formed at at least one end of the first interdigital finger, and a first gap is formed between the first connecting line and the first interdigital finger to separate the first interdigital finger from the first connecting line, and then the separated first interdigital finger and the first connecting line are electrically connected through the first interconnecting electrode. Compared with the conventional structure, the vibration obstruction of the interdigital finger by the metal structure outside the interdigital finger can be reduced, and the surface acoustic wave at the end of the first interdigital finger is avoided to be disturbed. In addition, the first interdigital finger and the first connecting line form an impedance mismatching area at the first gap, thereby effectively suppressing the leakage of clutter, thereby improving the Q value of the resonator; similarly, a second connecting line is formed at at least one end of the second interdigital finger, and a second gap is formed between the second connecting line and the second interdigital finger to separate the second interdigital finger from the second connecting line, and then the separated second interdigital finger and the second connecting line are electrically connected through the second interconnecting electrode. Compared with the conventional structure, the vibration obstruction of the interdigital finger by the metal structure outside the interdigital finger can be reduced, and the surface acoustic wave at the end of the second interdigital finger is avoided to be disturbed. In addition, the second interdigital finger and the second connecting line form an impedance mismatching area at the second gap, thereby effectively suppressing the leakage of clutter, thereby improving the Q value of the resonator.

[0023] Furthermore, the broken first fork finger is electrically connected to the first connecting wire through the arch bridge structure, so as to facilitate the electrical connection of the first fork finger with the outside. Similarly, the broken second fork finger is electrically connected to the second connecting wire through the second arch bridge structure, so as to facilitate the electrical connection of the second fork finger with the outside. In addition, the arch bridge structure can make the ends of the corresponding fork finger and the connecting wire completely exposed to the gas in the first gap, so as to better avoid the vibration drag of the connecting wire on the end of the fork finger and avoid disturbing the surface acoustic wave of the end of the fork finger. Further, when the first sub-arch bridge includes at least one, it is necessary to set a support structure under the connection part between adjacent sub-arch bridges to support the first arch bridge structure, avoid the poor structural strength caused by the excessive first gap, and thus improve the Q value of the resonator; similarly, when the second sub-arch bridge includes at least one, it is necessary to set a support structure under the connection part between adjacent sub-arch bridges to avoid the poor structural strength of the second arch bridge structure caused by the excessive second gap, and thus improve the Q value of the resonator.

[0024] Furthermore, the impedance of the first interconnected electrode and the second interconnected electrode is lower than the impedance of the first interdigital finger and the second interdigital finger, respectively, so as to reduce the impedance of the first interdigital finger and the second interdigital finger, and make the first interdigital electrode and the second interdigital electrode have better conductivity, thereby improving the conductivity.

[0025] Furthermore, the IDT uses a metal material with lower resistivity and better thermal conductivity, which can reduce impedance and enhance thermal conductivity.

[0026] Furthermore, both ends of the first interdigital finger and / or the second interdigital finger are provided with connecting wires, and power is supplied to both ends of the first interdigital finger and / or the second interdigital finger through the connecting wires to improve power supply efficiency.

[0027] The beneficial effects of the method for manufacturing the thin film surface acoustic wave resonator of the present invention are:

[0028] A first interdigitated finger and a first connecting line are formed, and a first gap is formed between the first interdigitated finger and the first connecting line to separate the end of the first interdigitated finger from the end of the first connecting line, and then a first interconnecting electrode is formed to connect the separated ends of the first interdigitated finger and the first connecting line, so that the end of the first interdigitated finger and the end of the first connecting line are exposed to the first gap at the first gap, thereby facilitating the suppression of the first connecting line from generating clutter, thereby preventing it from causing disturbance to the surface acoustic wave at the end of the first interdigitated finger; similarly, a second interdigitated finger and a second connecting line are formed, and a second gap is formed between the second interdigitated finger and the second connecting line to separate the end of the second interdigitated finger from the end of the second connecting line, and then a second interconnecting electrode is formed to connect the separated ends of the second interdigitated finger and the second connecting line, thereby preventing the clutter generated by the second connecting line from causing disturbance to the surface acoustic wave at the end of the second interdigitated finger.

[0029] Furthermore, when forming corresponding interdigitated electrodes and corresponding connecting lines, the interdigitated electrodes can be formed synchronously with the connecting lines, or can be formed before or after forming the connecting lines. When the interdigitated electrodes are formed synchronously with the connecting lines, process steps can be saved and efficiency can be improved.

[0030] Furthermore, when the corresponding interconnected electrode includes at least one sub-arch bridge, a supporting structure can be formed in the corresponding gap to support the corresponding arch bridge structure and improve the structural strength of the resonator. When the supporting structure is formed synchronously with the interdigitated electrodes and connecting lines, process steps can be saved and efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A schematic structural diagram of a thin film surface acoustic wave resonator provided by Embodiment 1 of the present invention is shown;

[0033] Figure 2 A cross-sectional view of the thin film surface acoustic wave resonator along AA and BB in Example 1 of the present invention is shown;

[0034] Figure 3 A schematic cross-sectional structure diagram of a thin film surface acoustic wave resonator provided by Embodiment 2 of the present invention is shown;

[0035] Figure 4 A schematic structural diagram of a thin film surface acoustic wave resonator provided by Embodiment 3 of the present invention is shown;

[0036] Figure 5 A schematic structural diagram of another thin film surface acoustic wave resonator provided by Embodiment 3 of the present invention is shown;

[0037] Figures 6 to 15 A structural schematic diagram corresponding to different steps of the method for manufacturing a thin film surface acoustic wave resonator according to embodiment 4 of the present invention is shown.

[0038] Description of reference numerals:

[0039] 1. first interdigitated electrode; 11. first interdigitated finger; 2. second interdigitated electrode; 21. second interdigitated finger; 3. first connecting line; 4. second connecting line; 5. first gap; 6. second gap; 7. first interconnecting electrode; 71. first arch bridge structure; 72. first gap; 8. second interconnecting electrode; 81. second arch bridge structure; 82. second gap; 91. substrate; 92. piezoelectric layer; 93. supporting structure; 94. isolation layer; 95. sacrificial layer; 96. first protrusion; 97. second protrusion; 98. first pad; 99. second pad. DETAILED DESCRIPTION

[0040] The thin film surface acoustic wave resonator and the method for making the same are further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer according to the following description and drawings. However, it should be noted that the concept of the technical solution of the present invention can be implemented in a variety of different forms and is not limited to the specific embodiments described herein. The drawings are all in a very simplified form and are not in precise proportions to facilitate and clearly assist in explaining the purpose of the embodiments of the present invention.

[0041] The terms "first", "second", etc. in the specification and claims are used to distinguish between similar elements and are not necessarily used to describe a specific order or time sequence. It is to be understood that, where appropriate, these terms used in this way are interchangeable, for example, so that the embodiments of the invention described herein can be operated in an order other than that described or shown herein. Similarly, if the method described herein includes a series of steps, the order of these steps presented herein is not necessarily the only order in which these steps can be performed, and some of the steps described may be omitted and / or some other steps not described herein may be added to the method. If the components in a certain figure are the same as the components in other figures, although these components can be easily identified in all figures, in order to make the description of the figures clearer, this specification will not mark all the same component numbers in each figure.

[0042] Example 1

[0043] Embodiment 1 provides a thin film surface acoustic wave resonator, Figure 1 A cross-sectional schematic diagram of a thin film surface acoustic wave resonator provided in Example 1 of the present invention, please refer to Figure 1 and Figure 2 , the thin film surface acoustic wave resonator comprises:

[0044] A first interdigital electrode 1 having a plurality of first interdigital fingers 11, and a second interdigital electrode 2 having a plurality of second interdigital fingers 21, wherein the first interdigital fingers 11 and the second interdigital fingers 21 are arranged at intervals;

[0045] A first connecting line 3, located at at least one end of the first interdigital finger 11, and electrically connected to the first interdigital finger 11;

[0046] The second connecting line 4 is located at at least one end of the second interdigital finger 21 and is electrically connected to the second interdigital finger 21;

[0047] There is a first gap 5 between the first connecting line 3 and the first interdigital finger 11, and the first connecting line 3 and the first interdigital finger 11 are connected via a first interconnection electrode 7 spanning the first gap 5;

[0048] and / or,

[0049] There is a second gap 6 between the second connecting line 4 and the second interdigital finger 21 , and the second connecting line 4 and the second interdigital finger 21 are connected via a second interconnection electrode 8 spanning the second gap 6 .

[0050] In this embodiment, a first connecting line 3 is formed at both ends of the first interdigital finger 11, and a second connecting line 4 is formed at both ends of the second interdigital finger 21, so that a first gap 5 is provided between the first connecting line 3 and the end of the first interdigital finger 11, and a second gap 6 is provided between the second connecting line 4 and the end of the second interdigital finger 21, so that the corresponding connecting line and the corresponding interdigital finger are separated by the first gap 5 and the second gap 6, respectively, so as to reduce the vibration obstruction of the metal structure outside the interdigital finger to the interdigital finger, and at the same time, avoid the noise generated by the connecting line from causing disturbance to the surface acoustic wave at the end of the interdigital finger when electrically connected; the corresponding connecting line and the interdigital electrode form an impedance mismatching area at the corresponding gap, and the connecting line and the interdigital electrode are connected by the interconnecting electrode, so that the leakage of the noise can be effectively suppressed. In addition, by arranging connecting lines at both ends of the corresponding interdigital finger, the two ends of the corresponding interdigital finger are in a balanced state, thereby improving the stability of the device structure. The interconnected electrodes, gaps, connecting lines and interdigitals correspond to each other, that is, the first interconnected electrode corresponds to the first gap 5 , the first connecting line 3 and the first interdigital finger 11 ; the second interconnected electrode corresponds to the second gap 6 , the second connecting line 4 and the second interdigital finger 21 .

[0051] The first connecting wire 3 and the second connecting wire 4 located on the same side of the first interdigital finger 11 and the second interdigital finger 21, one of which is located on the outside of the other, and the connecting wire located on the inside passes through the gap between the connecting wire on the outside and the corresponding interdigital finger, so that the two ends of the first interdigital electrode 1 and the second interdigital electrode 2 are in a better balance state, thereby improving the stability of the device structure. Specifically, when the first connecting wire 3 located on the same side is located on the inside of the second connecting wire 4, the first connecting wire 3 located on the other same side is located on the outside of the second connecting wire 4. It should be noted that the materials of the first connecting wire 3 and the second connecting wire 4 can refer to the materials of the first interdigital electrode 1 and the second interdigital electrode 2, see below for details. In other embodiments, the materials of the first connecting wire 3 and the second connecting wire 4 can be conductive materials, such as a combination of one or more of molybdenum, aluminum, copper, tungsten, tantalum, platinum, ruthenium, rhodium, iridium, chromium, titanium, gold, osmium, rhenium or palladium.

[0052] In this embodiment, in order to facilitate the formation of the first connecting line 3, the second connecting line 4, the first interdigitated electrode 1 and the second interdigitated electrode 2 and simplify the manufacturing process, the side of the first connecting line 3 facing the first interconnect electrode 7 is flush with the side of the first interdigitated electrode 11 facing the first interconnect electrode 7; and / or, the side of the second connecting line 4 facing the second interconnect electrode 8 is flush with the side of the second interdigitated electrode 21 facing the second interconnect electrode 8.

[0053] The first interconnecting electrode 7 crosses the first gap 5 to connect the first interdigital finger 11 and the first connecting line 3, and can electrically connect the disconnected first interdigital finger 11 and the first connecting line 3. The second interconnecting electrode 8 crosses the second gap 6 to connect the second interdigital finger 21 and the second connecting line 4, and can electrically connect the disconnected second interconnecting electrode 8 across the second gap 6. In this embodiment, the impedance of the first interconnecting electrode 7 is lower than the impedance of the first interdigital electrode 1, and the impedance of the second interconnecting electrode 8 is lower than the impedance of the second interdigital electrode 2, so that when the corresponding connecting line and the interdigital electrode are electrically connected through the interconnecting electrode, the impedance of the corresponding interdigital electrode is reduced, so that the first interdigital electrode 1 and the second interdigital electrode 2 have better conductivity and improve the conductivity. The material of the first interconnecting electrode 7 and the second interconnecting electrode 8 is a metal material, and the metal material includes one or more of gold, silver, tungsten, platinum, aluminum, copper, titanium, tin, and nickel.

[0054] The number of the first interconnecting electrodes 7 is at least one. When the first interconnecting electrodes 7 are an integral structure, the first interconnecting electrodes 7 cover the first interdigital fingers 11 and extend to the two ends of the first interdigital fingers 11, and respectively cross the first gaps 5 at the two ends thereof to extend to the first connecting wires 3, thereby electrically connecting the first connecting wires 3 at the two ends of the first interdigital fingers 11 to the first interdigital fingers 11; when the number of the first interconnecting electrodes 7 is at least two, the first interconnecting electrodes 7 are disposed at the two ends of the first interdigital fingers 11 to respectively connect the first connecting wires 3 at the two ends of the first interdigital fingers 11 to the ends of the first interdigital fingers 11. It should be noted that the number of the second interconnecting electrodes 8 can be set with reference to the first interconnecting electrodes 7, and will not be repeated here. In addition, in the present embodiment, the number of the first interconnecting electrodes 7 and the second interconnecting electrodes 8 both include at least two, and are respectively disposed at the two ends of the corresponding interdigital fingers to respectively connect the ends of the corresponding interdigital fingers and the corresponding connecting wires at the ends.

[0055] In this embodiment, the first interconnecting electrode 7 includes a first arch bridge structure 71 protruding away from the first gap 5, the inner surface of the first arch bridge structure 71 encloses a first gap 72, and the first gap 72 is opposite to the first gap 3; and / or, the second interconnecting electrode 8 includes a second arch bridge structure 81 protruding away from the second gap 6, the inner surface of the second arch bridge structure 81 encloses a second gap 82, and the second gap 82 is opposite to the second gap 6. By forming a corresponding arch bridge structure on the interconnecting electrode, the end of the corresponding fork finger is fully exposed to the gap, so that the surface acoustic wave of the end of the connecting wire when it is electrically connected to the corresponding fork finger can be better avoided, and the leakage of the acoustic wave can be effectively suppressed. Specifically, the first arch bridge structure 71 includes at least one sub-arch bridge, and a support structure 93 is arranged below the connection part between adjacent sub-arch bridges; and / or, the second arch bridge structure 81 includes at least one sub-arch bridge, and a support structure 93 is arranged below the connection part between adjacent sub-arch bridges.

[0056] It should be noted that the first gap 72 is opposite to the first gap 5, that is, the projection of the first gap 5 on the plane where the surface of the first connecting line 3 is located is within the projection range of the first gap 72 on the plane where the surface of the first connecting line 3 is located, or the projection of the first gap 5 on the plane where the surface of the first connecting line 3 is located partially overlaps with the projection of the first gap 72 on the plane where the surface of the first connecting line 3 is located. When the projection of the first gap 5 on the plane where the surface of the first connecting line 3 is located is within the projection range of the first gap 72 on the plane where the surface of the first connecting line 3 is located, the effect of suppressing the leakage of sound waves is better, and the disturbance of the end of the first interdigital finger 11 by the leaked clutter is effectively avoided. The second gap 82 and the second gap 6 can be set relative to each other with reference to the first gap 72 and the first gap 5, which will not be repeated here.

[0057] In addition, the support structure 93 is arranged in the corresponding gap, and the support structure 93 can divide the gap into at least two mutually isolated sub-gaps, or the support structure 93 can divide the gap into at least two connected sub-gaps. Since the support structure 93 needs to support the interconnected electrode when the corresponding interconnected electrode crosses the gap, its structure is not specifically limited. The adjacent sub-gaps isolated by the support structure 93 can be partially connected or completely isolated, and the inner surface of the sub-arch bridge is surrounded by a gap, and the gap is opposite to the sub-gaps one by one. The support structure 93 can be made of the same material as the first connecting line 3 and the second connecting line 4, or a dielectric material, including but not limited to one of silicon oxide, silicon nitride, silicon oxynitride, silicon carbonitride and the like.

[0058] Since the gap between the connecting line located on the outside and the corresponding interdigital finger may be large, so as to affect the stability of the corresponding interconnected electrode across the gap, the interconnected electrode connected to the connecting line located on the outside and the corresponding interdigital finger includes a first sub-arch bridge and a second sub-arch bridge, a support structure 93 is arranged below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, and the second sub-arch bridge is located on the outside and crosses the inner support structure 93 to connect with the connecting line on the outside. Taking the first connecting line 3 located on the same side as an example, which is located on the outside of the second connecting line 4, the first interconnected electrode 7 connecting the first connecting line 3 located on the outside and the first interdigital finger 11 includes a first sub-arch bridge and a second sub-arch bridge, a support structure 93 is arranged below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, the first sub-arch bridge is located on the inside and crosses the inner first interdigital finger 11 and is connected to the outer support structure 93, the second sub-arch bridge is located on the outside and crosses the inner support structure 93 and is connected to the connecting line on the outside, and the second interconnected electrode 8 connecting the second connecting line 4 located on the inside and the second interdigital finger 21 includes a third sub-arch bridge, and the third sub-arch bridge crosses the inner second interdigital finger 21 and is connected to the second connecting line 4 on the outside. It should be noted that when the first connecting line 3 on the other same side is located on the inner side of the second connecting line 4, that is, when the second connecting line 4 on this side is located on the outer side of the first connecting line 3, refer to the setting of the first connecting line 3 being located on the outer side of the second connecting line 4 described above, and no further details will be given here.

[0059] In this embodiment, the two ends of the first interdigital finger 11 are electrically connected to the first connecting wire 3 through the first interconnecting electrode 7, and the two ends of the second interdigital finger 21 are electrically connected to the second connecting wire 4 through the second interconnecting electrode 8. Specifically, the first connecting wires 7 provided at the two ends of the first interdigital finger 11 are connected to the same first pad 98, so that signals are input to the two ends of the first interdigital finger 11 through the two first connecting wires 3 or signals are output from the two ends of the first interdigital finger 11, thereby improving the power supply efficiency, and the second connecting wires 8 provided at the two ends of the second interdigital finger 21 are connected to the same second pad 99, so that signals are input to the two ends of the second interdigital finger 21 through the two second connecting wires 4 or signals are output from the two ends of the second interdigital finger 21, thereby improving the efficiency of signal input or output. When the first interdigital electrode 1 is used as a signal input end, the second interdigital electrode 2 is used as a signal output end. In actual use, after the first interdigital electrode 1 and the second interdigital electrode 2 are connected to alternating current, the first interdigital electrode 1 and the second interdigital electrode 2 are used as signal input ends and signal output ends respectively and are in a process of dynamic change.

[0060] In other embodiments, one end of the first fork finger 11 is electrically connected to one end of the first connecting line 3 through the first interconnecting electrode 7, and the other end is pseudo-interconnected with the first connecting line 3, that is, the first connecting line 3 at one end of the first fork finger 11 is electrically connected to the external first soldering pad 98, and the first connecting line 3 at the other end of the first fork finger 11 is not powered. The connection structure between the second fork finger 21 and the second interconnecting electrode 8, the second connecting line 4, and the second soldering pad 99 refers to the connection structure between the first fork finger 11 and the first interconnecting electrode 7, the first connecting line 3, and the first soldering pad 98, and will not be repeated here.

[0061] In other embodiments, one end of the first interdigital finger 11 is electrically connected to one end of the first connection line 3 through the first interconnection electrode 7 , and the other end of the first interdigital finger 11 is in contact and electrically connected to the first connection line 3 .

[0062] Similarly, the electrical connection of the second connecting wires 4 at both ends of the second interdigital fingers 21 may refer to the electrical connection of the first connecting wires 3 at both ends of the first interdigital fingers 11, which will not be described in detail here.

[0063] Generally, the first interdigitated electrode 1 and the second interdigitated electrode 2 can use any suitable conductive material or semiconductor material known to those skilled in the art, wherein the conductive material can be a metal material with conductive properties, for example, made of one of metals such as molybdenum (Mo), aluminum (Al), copper (Cu), tungsten (W), tantalum (Ta), platinum (Pt), ruthenium (Ru), rhodium (Rh), iridium (Ir), chromium (Cr), titanium (Ti), gold (Au), osmium (Os), rhenium (Re), palladium (Pd), or a stack of the above metals, and the semiconductor material is, for example, Si, Ge, SiGe, SiC, SiGeC, etc. The material of the first interdigitated finger 11 and the second interdigitated finger 21 can be a conductive material with low impedance, such as one or more of gold, silver, tungsten, platinum, aluminum, and copper.

[0064] In the present embodiment, the interdigital electrodes and the connecting wires are both disposed on the piezoelectric layer 92, and the material of the piezoelectric layer 92 can be aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate (PZT), lithium niobate (LiNbO3), quartz (Quartz), potassium niobate (KNbO3) or lithium tantalate (LiTaO3) and other piezoelectric materials with a wurtzite crystal structure and combinations thereof. When the piezoelectric layer 92 includes aluminum nitride (AlN), the piezoelectric layer 92 may also include rare earth metals, such as scandium (Sc), erbium (Er), yttrium (Y) and lanthanum (La). In addition, when the piezoelectric layer 92 includes aluminum nitride (AlN), the piezoelectric layer 92 may also include transition metals, such as zirconium (Zr), titanium (Ti), manganese (Mn) and hafnium (Hf). The piezoelectric layer may be formed by deposition using any suitable method known to those skilled in the art, such as chemical vapor deposition, physical vapor deposition or atomic layer deposition.

[0065] The piezoelectric layer 92 is disposed on the substrate 91, and the piezoelectric layer 92 can be combined with the substrate 91 by deposition or bonding. The bonding method includes: covalent bonding, adhesive bonding or melt bonding, and the deposition method can be chemical vapor deposition or physical vapor deposition. In other embodiments, the substrate 91 and the piezoelectric layer 92 can also be bonded through a bonding layer, and the material of the bonding layer includes silicon oxide, silicon nitride, silicon oxynitride, silicon carbon nitride or ethyl silicate. In addition, the bonding layer can also use adhesives such as photocurable materials or thermosetting materials, such as die attach film (DAF) or dry film (Dry Film). The material of the substrate 91 can be any suitable substrate known to those skilled in the art, for example, it can be at least one of the following materials: silicon (Si), germanium (Ge), silicon germanium (SiGe), carbon silicon (SiC), carbon germanium silicon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP) or other III / V compound semiconductors. It should be noted that the substrate 91 may include a sound reflection area or may not include a sound reflection area. When a sound reflection area is provided on the substrate 91, the sound reflection area may be a cavity or a Bragg reflection layer.

[0066] Example 2

[0067] Embodiment 2 provides a thin film surface acoustic wave resonator. Figure 3 The cross-sectional structure diagram of the thin film surface acoustic wave resonator of Example 2 of the present invention is different from Example 1 in that the interconnecting electrodes connecting the connecting wires located on the inner side of the same side and the corresponding interdigital fingers in Example 1 include the third sub-arch bridge, while the interconnecting electrodes connecting the connecting wires located on the inner side of the same side and the corresponding interdigital fingers in Example 2 include the third sub-arch bridge and the fourth sub-arch bridge, which can effectively reduce the vibration obstruction of the interdigital fingers by the metal structure outside the interdigital fingers, and avoid disturbing the surface acoustic waves at the ends of the interdigital electrodes. Specifically:

[0068] Taking the first connecting line 3 located on the same side as the outer side of the second connecting line 4 as an example, the first interconnecting electrode 7 connecting the first connecting line 3 located on the outer side and the first interdigital finger 11 includes a first sub-arch bridge and a second sub-arch bridge, and a support structure 93 is arranged below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, the first sub-arch bridge is located on the inner side and crosses the inner first interdigital finger 11 and is connected to the outer support structure 93, the second sub-arch bridge is located on the outer side and crosses the inner support structure 93 and is connected to the outer connecting line, the second interconnecting electrode 8 connecting the second connecting line 4 located on the inner side and the second interdigital finger 21 includes a third sub-arch bridge and a fourth sub-arch bridge, the third sub-arch bridge is located on the inner side and crosses the inner second interdigital finger 21 and is connected to the outer support structure 93, and the second sub-arch bridge is located on the outer side and crosses the inner support structure 93 and is connected to the outer second connecting line 4. Other structural features of the thin film surface acoustic wave resonator of this embodiment are the same as those of embodiment 1 and will not be repeated here.

[0069] Example 3

[0070] Embodiment 3 provides a thin film surface acoustic wave resonator, Figure 4-Figure 5 Schematic diagram of the cross-sectional structure of the thin film surface acoustic wave resonator of Example 3 of the present invention. The difference between this embodiment and Example 1 is that in Example 1, connecting wires are respectively provided at both ends of the first interdigital finger 11 and the second interdigital finger 21, while in Example 3, connecting wires are provided at one end of the first interdigital finger 11 and the second interdigital finger 21. Specifically:

[0071] A first connecting line 3 is disposed at one end of the first interdigital finger 11 , and a second connecting line 4 is disposed at one end of the second interdigital finger 21 . The first connecting line 3 and the second connecting line 4 are located at the same side or different sides of the first interdigital finger 11 and the second interdigital finger 21 .

[0072] Reference Figure 4 When the first connecting line 3 and the second connecting line 4 are located on the same side, the first connecting line 3 can be located on the outside of the second connecting line 4, and its specific structure with the corresponding interconnected electrode refers to the above-mentioned embodiment 1; or, the first connecting line can be located on the inside of the second connecting line 4, and its specific structure with the corresponding interconnected electrode refers to the above-mentioned embodiment 2.

[0073] Reference Figure 5 , when the first connection line 3 and the second connection line 4 are located on different sides, the first interconnection electrode 7 connecting the first connection line 3 and the first interdigital finger 11 includes a first sub-arch bridge and a second sub-arch bridge; or, the first interconnection electrode 7 connecting the first connection line 3 and the first interdigital finger 11 includes a third sub-arch bridge, and its specific structure refers to the above embodiment 1. Similarly, the second interconnection electrode 8 connecting the second connection line 4 and the second interdigital finger 21 includes a first sub-arch bridge and a second sub-arch bridge; or, the second interconnection electrode 8 connecting the second connection line 4 and the second interdigital finger 21 includes a third sub-arch bridge, and its specific structure refers to the above embodiment 1.

[0074] Example 4

[0075] Embodiment 4 provides a method for manufacturing a thin film surface acoustic wave resonator. The method for manufacturing a thin film surface acoustic wave resonator comprises:

[0076] S01: providing a piezoelectric layer;

[0077] S02: forming a first interdigital electrode having a plurality of first interdigital fingers and a second interdigital electrode having a plurality of second interdigital fingers on the piezoelectric layer, wherein the first interdigital fingers and the second interdigital fingers are arranged at intervals;

[0078] forming a first connecting line, wherein the first connecting line is formed at least at one end of the first interdigitated finger and has a first gap between the first connecting line and the first interdigitated finger;

[0079] and / or,

[0080] forming a second connecting line, wherein the second connecting line is formed at least at one end of the second interdigital finger and has a second gap between the second interdigital finger and the second interdigital finger;

[0081] S03: forming a first interconnect electrode, the first interconnect electrode spanning the first gap and electrically connecting the first interdigital finger and the first connecting line; forming a second interconnect electrode, the second interconnect electrode spanning the second gap and electrically connecting the second interdigital finger and the second connecting line.

[0082] Steps S0N do not represent a sequential order.

[0083] Figures 6 to 15 FIG. 1 is a schematic diagram of the structure corresponding to the corresponding steps of the method for manufacturing a thin film bulk acoustic wave resonator of this embodiment, with reference to FIG. Figures 6 to 15 The method for manufacturing the thin film bulk acoustic wave resonator provided in this embodiment is described in detail.

[0084] refer to Figure 6 , providing a piezoelectric layer 92.

[0085] In this embodiment, the thickness of the piezoelectric layer 92 is less than 0.3 microns. In this case, before providing the piezoelectric layer 92, a substrate 91 needs to be provided first, and then a thin piezoelectric layer 92 is deposited on the substrate 91. The material of the piezoelectric layer 92 is as described in Example 1, and will not be described again here. In other embodiments, the piezoelectric layer 92 is a thick piezoelectric wafer with a thickness greater than 20 microns. In the later process, the step of thinning the piezoelectric wafer is also included to make its thickness meet the requirements for generating resonance.

[0086] refer to Figure 7-11 , a first interdigital electrode, a second interdigital electrode, a first connecting line 3, and a second connecting line 4 are formed on the piezoelectric layer 92.

[0087] Reference Figure 7-Figure 10In another possible implementation, the first connecting line 3, the second connecting line 4 and the first interdigitated electrode, the second interdigitated electrode are made of different materials, and the method of forming the first connecting line 3, the second connecting line 4, the first interdigitated electrode and the second interdigitated electrode includes: forming a first conductive layer on the piezoelectric layer 92, and patterning the first conductive layer to form the first interdigitated electrode and the second interdigitated electrode; forming a second conductive layer on the piezoelectric layer 92, and patterning the second conductive layer to form the first connecting line 3 and the second connecting line 4.

[0088] Specifically, refer to Figure 7-Figure 8 , the first interdigital electrode 1 and the second interdigital electrode 2 can be formed first, and then the first connecting line 3 and the second connecting line 4 can be formed by a lift-off process. The method for forming the first interdigital electrode 1 and the second interdigital electrode 2 includes: depositing a first conductive layer on the piezoelectric layer 92; applying a photoresist to the surface of the first conductive layer to form a photoresist layer; defining a mask pattern according to the desired patterns of the first interdigital electrode 1 and the second interdigital electrode 2, and then exposing the mask pattern to transfer the mask pattern to the photoresist layer; developing the photoresist layer; using the developed photoresist layer as a mask, etching the first conductive layer by a dry etching process to form the first interdigital electrode 1 and the second interdigital electrode; and removing the photoresist layer.

[0089] Specifically, after forming the first interdigital electrode 1 and the second interdigital electrode 2, an isolation layer 94 is first deposited to cover the first interdigital electrode 1, the second interdigital electrode 2 and the piezoelectric layer 92 outside the first interdigital electrode 1 and the second interdigital electrode 2. Figure 7 Then pattern the isolation layer 94 to form a first forming hole; form a second conductive layer to fill the first forming hole and cover the isolation layer 94, refer to Figure 8 Finally, the second conductive layer on the isolation layer 94 is removed, and the isolation layer is removed to form the first connection line 3 and the second connection line 4.

[0090] It should be noted that before the isolation layer 94 is patterned, the isolation layer 94 needs to be flattened. After the second conductive layer is formed, the isolation layer 94 and the second conductive layer formed by deposition need to be flattened to expose the first interdigital electrode 1 and the second interdigital electrode 2 covered by the isolation layer 94, so that the side of the second conductive layer facing the subsequent interconnection electrode is flush with the side of the first interdigital electrode 1 and the second interdigital electrode 2 facing the subsequent interconnection electrode, that is, the side of the first connecting line 3 and the second connecting line 4 formed facing the subsequent interconnection electrode is flush with the side of the first interdigital electrode 1 and the second interdigital electrode 2 facing the subsequent interconnection electrode. The first forming hole can be determined according to the required formation position of the first connecting line 3 and the second connecting line 4, so that at least one end of the first interdigital 11 forms the first connecting line 3; and / or, at least one end of the second interdigital 21 forms the second connecting line 4. In addition, the formed first connecting line 3 and the second connecting line 4 can be located on the same side or different sides of the interdigital electrode.

[0091] In order to facilitate the removal of the isolation layer, the material of the isolation layer includes but is not limited to at least one of silicon dioxide, silicon nitride, aluminum oxide and aluminum nitride or thermal expansion tape; or, the material of the isolation layer includes phosphosilicate glass, low-temperature silicon dioxide, borophosphosilicate glass, germanium, carbon, polyimide or photoresist; or, the material of the isolation layer can be photoresist. By forming the isolation layer after forming the interdigital electrodes and before forming the connecting wires, the connecting wires and the interdigital electrodes are isolated, thereby effectively preventing the later formed connecting wires from covering the earlier formed interdigital electrodes.

[0092] In addition, refer to Figure 9-10 Alternatively, the first connecting wire 3 and the second connecting wire 4 may be formed first, and then the first interdigital electrode 1 and the second interdigital electrode 2 may be formed by a lift-off process. The method for forming the first connecting wire 3 and the second connecting wire 4 may refer to the method for forming the first interdigital electrode 1 and the second interdigital electrode 2 described above. It should be noted that when defining the mask pattern, the mask pattern needs to be defined according to the first connecting wire 3 and the second connecting wire 4. In addition, the formation positions of the first connecting wire 3 and the second connecting wire 4 are related to the patterning and can be determined by defining the mask pattern.

[0093] Specifically, after forming the first connecting wire 3 and the second connecting wire 4, an isolation layer 94 is first deposited to cover the first connecting wire 3, the second connecting wire 4 and the piezoelectric layer 92. Fig. 9 The isolation layer 94 is then patterned to form a second forming hole; a second conductive layer is formed to fill the second forming hole and cover the isolation layer 94. Finally, the second conductive layer on the isolation layer is removed, and the isolation layer is removed; the second conductive layer in the second forming hole is patterned to form a first interdigital electrode 1 and a second interdigital electrode 2, referring to Fig.10 .

[0094] It should be noted that before patterning the isolation layer 94, the isolation layer 94 needs to be flattened first; after forming the second conductive layer, the deposited isolation layer 94 and the second conductive layer need to be flattened to expose the first connection line 3 and the second connection line 4 covered by the isolation layer 94, so that the side of the second conductive layer facing the subsequent interconnection electrode is flush with the side of the first connection line 3 and the second connection line 4 facing the subsequent interconnection electrode, that is, the side of the first interdigitated electrode 1 and the second interdigitated electrode 2 facing the subsequent interconnection electrode is flush with the side of the first connection line 3 and the second connection line 4 facing the subsequent interconnection electrode. The second forming hole can be set according to the shape of the first interdigitated electrode 1 and the second interdigitated electrode 2. The process of patterning the first interdigitated electrode 1 and the second interdigitated electrode 2 can refer to the above description and will not be repeated here.

[0095] Continue to refer to Fig.10In a possible implementation, the first connection line 3, the second connection line 4, the first interdigital electrode and the second interdigital electrode are made of the same material, and the first connection line 3, the second connection line 4, the first interdigital electrode 1 and the second interdigital electrode 2 can be formed simultaneously, specifically: forming a conductive layer on the piezoelectric layer 92; patterning the conductive layer to form the first connection line 3, the second connection line 4, the first interdigital electrode 1 and the second interdigital electrode 2. The method for forming the first connection line 3, the second connection line 4, the first interdigital electrode 1 and the second interdigital electrode 2 can refer to the above-mentioned method for forming the first interdigital electrode 1 and the second interdigital electrode 2. It should be noted that when defining the mask pattern, the mask pattern needs to be defined according to the first connection line 3, the second connection line 4, the first interdigital electrode 1 and the second interdigital electrode 2. It should be noted that the formation positions of the first connecting line 3 and the second connecting line 4 are related to the graphical processing. For example, by defining a mask graphic pattern, the two ends of the first fork finger 11 respectively form the first connecting line 3, or the first connecting line 3 is formed at one end of the first fork finger 11. Similarly, by defining a mask graphic pattern, the two ends of the second fork finger 21 respectively form the second connecting line 4, or the second connecting line 4 is formed at one end of the second fork finger 21. The formed first connecting line 3 and second connecting line 4 can be located on the same side or different sides of the fork finger electrode.

[0096] refer to Figure 11-Figure 15 , a first interconnection electrode 7 is formed, and a second interconnection electrode 8 is formed.

[0097] Specifically, after forming the first interdigitated electrode 1, the second interdigitated electrode 2, the first connecting line 3 and the second connecting line 4, the first interconnected electrode 7 and the second interconnected electrode 8 are formed. The first interconnected electrode 7 and / or the second interconnected electrode 8 include at least one sub-arch bridge, and a support structure 93 is formed between adjacent sub-arch bridges.

[0098] Reference Figure 11-13 In this embodiment, the support structure 93 is made of the same material as the first interdigital electrode 1 and the second interdigital electrode 2. The method for forming the first interconnection electrode 7 and the second interconnection electrode 8 includes: firstly forming the support structure 93 when forming the first interdigital electrode 1 and the second interdigital electrode 2 and / or when forming the first connection line 3 and the second connection line 4. Then forming a sacrificial layer 95 to fill the first gap and the second gap and cover the first interdigital electrode 1, the second interdigital electrode 2, the first connection line 3 and the second connection line 4, referring to Fig.11 The sacrificial layer 95 is then etched to form a first protrusion 96 and a second protrusion 97 and to expose the support structure 93, the interdigital electrodes and the connecting wires around the corresponding protrusions. The first protrusion 96 is located between the first connecting wire 3 and the end of the first interdigital electrode 11, and the second protrusion 97 is located between the second connecting wire 4 and the end of the second interdigital electrode 21. Fig.12Then, corresponding interconnecting electrodes are formed to cover the corresponding protrusions and the interdigital electrodes and connecting wires or the interdigital electrodes, connecting wires and supporting structures exposed at the periphery of the corresponding protrusions. Finally, the first protrusion, the second protrusion and the sacrificial layer are removed. Fig.13 .

[0099] It should be noted that when etching the sacrificial layer 95 to form the first protrusion 96 and the second protrusion 97, the exposed corresponding fingers may be part of the corresponding fingers around the corresponding protrusion or all of the corresponding fingers, so that the formed interconnected electrodes are disconnected on the corresponding fingers or continuously connected on the corresponding fingers.

[0100] The formed first interconnected electrode 7 includes a raised first arch bridge structure 71, and the formed second interconnected electrode 8 includes a raised second arch bridge structure 81. After removing the first protrusion 96, a first gap 5 and a first gap 72 are formed, and the first gap 5 and the first gap 72 are opposite to each other. The first gap 5 is located between the end of the first interdigitated finger 11 and the first connecting line 3, and the first gap 72 is located on the inner surface of the first arch bridge 71; after removing the second protrusion 97, a second gap 6 and a second gap 82 are formed, and the second gap 6 and the second gap 82 are opposite to each other. The second gap 6 is located between the end of the second interdigitated finger 21 and the second connecting line 4, and the second gap 82 is located on the inner surface of the second arch bridge structure 81. Please refer to the description in Example 1 for details, which will not be repeated here.

[0101] The material of the sacrificial layer 95 can be phosphosilicate glass, low-temperature silicon dioxide, borophosphosilicate glass, germanium, amorphous carbon, polyimide or photoresist. In addition, when removing the sacrificial layer 95, it is necessary to first form a release hole on the interconnect electrode, and then select a corresponding removal method according to the material of the sacrificial layer 95. For example, when the material of the sacrificial layer 95 is polyimide or photoresist, it is removed by ashing. The specific ashing method is that at a temperature of 250 degrees Celsius, oxygen chemically reacts with the sacrificial layer 95 through air, and the generated gas substances are volatilized through the release holes.

[0102] It should be noted that when the first connecting line 3 and the second connecting line 4 are located on the same side, a support structure 93 needs to be formed between the connecting line located on the outside and the corresponding forked finger end, so that the mask pattern can be used to determine the formation position of the support structure 93, thereby avoiding the situation of structural instability caused by too large a gap; after the sacrificial layer 95 is formed, it needs to be leveled; when forming the support structure 93, that is, in the process of graphically forming the first forked finger electrode 1, the second forked finger electrode 2 and / or the first connecting line 3, the second connecting line 4, it is also necessary to define the illumination pattern according to the support structure 93. In addition, the formed support structure 93 divides the corresponding gap into a plurality of sub-gaps; the interconnecting electrodes corresponding to the forked finger electrodes and connecting lines covering the corresponding protrusions and the exposed forked finger electrodes around them and the connecting lines include at least one sub-arch bridge, and the interconnecting electrodes corresponding to the forked finger electrodes, connecting lines and the support structure 93 covering the corresponding protrusions and the exposed forked finger electrodes around them and the connecting lines include at least two sub-arch bridges. The material and function of the sacrificial layer can refer to the material and function of the above-mentioned isolation layer, which will not be repeated here.

[0103] Reference Figure 14-15 In other embodiments, the support structure 93 is made of different materials from the first interdigital electrode 1, the second interdigital electrode 2, the first connecting line 3, and the second connecting line 4. Then, the method for forming the first interconnection electrode 7 and the second interconnection electrode 8 includes: firstly forming a sacrificial layer 95 to fill the first gap and the second gap and cover the first interdigital electrode 1, the second interdigital electrode 2, the first connecting line 3, and the second connecting line 4; then etching the sacrificial layer 95 to form a third forming hole; filling the third forming hole to form a support material layer, referring to Fig.14 Then, the sacrificial layer 95 is etched to form the first protrusion 96, the second protrusion 97 and the support structure 93, and the support structure 93, the interdigital electrodes and the connecting wires around the corresponding protrusion are exposed. Then, the corresponding interconnection electrodes are formed to cover the corresponding protrusion and the interdigital electrodes and the connecting wires or the interdigital electrodes, the connecting wires and the support structure exposed around the corresponding protrusion. Fig.15 Finally, the first protrusion, the second protrusion and the sacrificial layer are removed.

[0104] It should be noted that the support structure 93 can also be formed after the first protrusion 96 and the second protrusion 97 are formed and before the first interconnection electrode 7 and the second interconnection electrode 8 are formed, the first protrusion 96 and / or the second protrusion 97 are etched to form a third forming hole; the support structure 93 is formed and the third forming hole is filled. The removal of the first protrusion, the second protrusion and the sacrificial layer is described above and will not be repeated here.

[0105] It should be noted that the various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the structural embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0106] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A thin film surface acoustic wave resonator, characterized in that: include: A first interdigitated electrode having a plurality of first interdigitated fingers, and a second interdigitated electrode having a plurality of second interdigitated fingers, wherein the first interdigitated fingers and the second interdigitated fingers are arranged at intervals; A first connecting line, located at least at one end of the first interdigital finger and electrically connected to the first interdigital finger; A second connecting line, located at least at one end of the second interdigital finger and electrically connected to the second interdigital finger; There is a first gap between the first connecting line and the first interdigital finger, and the first connecting line and the first interdigital finger are connected via a first interconnection electrode spanning the first gap; and / or, There is a second gap between the second connecting line and the second finger, and the second connecting line and the second finger are connected via a second interconnection electrode spanning the second gap.

2. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The first connecting wires are respectively provided at both ends of the first interdigitated finger, and one end of the first interdigitated finger is electrically connected to the first connecting wire at one end through the first interconnection electrode, or one end of the first interdigitated finger is pseudo-interconnected with the first connecting wire, or one end of the first interdigitated finger is contact-electrically connected with the first connecting wire.

3. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The second connecting wires are respectively provided at both ends of the second interdigitated finger, and one end of the second interdigitated finger is electrically connected to the second connecting wire at one end through the second interconnection electrode, or one end of the second interdigitated finger is pseudo-interconnected with the second connecting wire through the second interconnection electrode, or one end of the second interdigitated finger is in contact and electrically connected with the second connecting wire.

4. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The first interconnect electrode comprises a first arch bridge structure protruding away from the first gap, the inner surface of the first arch bridge structure encloses a first gap, and the first gap is opposite to the first gap; and / or, The second interconnecting electrode includes a second arched bridge structure protruding away from the second gap, the inner surface of the second arched bridge structure encloses a second gap, and the second gap is opposite to the second gap.

5. The thin film surface acoustic wave resonator according to claim 4, characterized in that: The first arch bridge structure includes at least one sub-arch bridge, and a support structure is arranged below the connection between adjacent sub-arch bridges; and / or, The second arch bridge structure includes at least one sub-arch bridge, and a supporting structure is arranged below the connection between adjacent sub-arch bridges.

6. The thin film surface acoustic wave resonator according to claim 5, characterized in that: The supporting structure divides the corresponding gap into at least two adjacent sub-gaps, and the inner surface of the sub-arch bridges encloses a gap, and the gaps are opposite to the sub-gaps one by one.

7. The thin film surface acoustic wave resonator according to claim 1, characterized in that: A first connection line electrically connected to the first interdigitated finger and a second connection line electrically connected to the second interdigitated finger are located on the same side or on different sides.

8. The thin film surface acoustic wave resonator according to claim 1, characterized in that: A first connecting line and a second connecting line located on the same side, one of which is located outside the other, and the connecting line located on the inner side passes through a gap between the connecting line on the outer side and the corresponding interdigital finger; The interconnected electrodes connected to the corresponding forked fingers by the connecting wires located on the outside include a first sub-arch bridge and a second sub-arch bridge. A supporting structure is arranged under the adjacent parts of the first sub-arch bridge and the second sub-arch bridge. The second sub-arch bridge is located on the outside and crosses the inner supporting structure to be connected to the connecting wires on the outside.

9. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The first connecting lines are respectively provided at both ends of the first fork finger, and the second connecting lines are respectively provided at both ends of the second fork finger. The first connecting lines located on the first same side are arranged on the inner side of the second connecting lines, and the first connecting lines located on the second same side are arranged on the outer side of the second connecting lines.

10. The thin film surface acoustic wave resonator according to claim 9, characterized in that: The interconnection electrode connected to the corresponding interdigital fingers arranged on the outside includes a first sub-arch bridge and a second sub-arch bridge, a support structure is arranged below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, the first sub-arch bridge is located on the inside and crosses the interdigital fingers on the inside to connect with the support structure on the outside, and the second sub-arch bridge is located on the outside and crosses the support structure on the inside to connect with the outer connection line; The interconnection electrode connected to the inner connecting wire and the corresponding interdigital finger comprises a third sub-arch bridge, and the third sub-arch bridge spans the inner interdigital finger and is connected to the outer connecting wire; or, The interconnection electrode connected to the corresponding interdigital fingers arranged on the outside includes a first sub-arch bridge and a second sub-arch bridge, a support structure is arranged below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, the first sub-arch bridge is located on the inside and crosses the interdigital fingers on the inside to connect with the support structure on the outside, and the second sub-arch bridge is located on the outside and crosses the support structure on the inside to connect with the outer connection line; The interconnecting electrodes connected to the corresponding forked fingers arranged on the inner side include a third sub-arch bridge and a fourth sub-arch bridge, a supporting structure is arranged under the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, the third sub-arch bridge is located on the inner side and crosses the inner forked fingers to be connected to the outer supporting structure, and the fourth sub-arch bridge is located on the outer side and crosses the inner supporting structure to be connected to the outer connecting wire.

11. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The impedance of the first interconnection electrode is lower than the impedance of the first interdigital finger, and the impedance of the second interconnection electrode is lower than the impedance of the second interdigital finger.

12. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The material of the first interconnect electrode and the second interconnect electrode is a metal material, and the metal material includes one or more of gold, silver, tungsten, platinum, aluminum, copper, titanium, tin, and nickel.

13. The thin film surface acoustic wave resonator according to claim 1, characterized in that: A side of the first connecting line facing the first interconnecting electrode is flush with a side of the first interdigitated finger facing the first interconnecting electrode; and / or, A surface of the second connecting line facing the second interconnecting electrode is flush with a surface of the second interdigital finger facing the second interconnecting electrode.

14. The thin film surface acoustic wave resonator according to claim 1, characterized in that: The material of the first interdigitated finger and the second interdigitated finger includes one or more combinations of gold, silver, tungsten, platinum, aluminum, and copper.

15. The thin film surface acoustic wave resonator according to claim 1, characterized in that: It also includes a piezoelectric layer, and the first interconnection electrode, the second interconnection electrode, the first connection line and the second connection line are all arranged on the piezoelectric layer.

16. The thin film surface acoustic wave resonator according to claim 15, characterized in that: The material of the piezoelectric layer includes aluminum nitride, zinc oxide, lead zirconate titanate, lithium niobate, quartz, potassium niobate or lithium tantalate.

17. The surface acoustic wave resonator according to claim 15, characterized in that: Also included is a substrate bonded to the piezoelectric layer.

18. A method for manufacturing a thin film surface acoustic wave resonator, characterized in that: include: providing a piezoelectric layer; forming a first interdigital electrode having a plurality of first interdigital fingers and a second interdigital electrode having a plurality of second interdigital fingers on the piezoelectric layer, wherein the first interdigital fingers and the second interdigital fingers are arranged at intervals; forming a first connecting line, wherein the first connecting line is formed at least at one end of the first interdigitated finger and has a first gap between the first connecting line and the first interdigitated finger; and / or, forming a second connecting line, wherein the second connecting line is formed at least at one end of the second interdigital finger and has a second gap between the second connecting line and the second interdigital finger; forming a first interconnecting electrode, the first interconnecting electrode spanning the first gap and electrically connecting the first interdigitated finger and the first connecting line; A second interconnection electrode is formed, the second interconnection electrode spanning the second gap and electrically connecting the second interdigital finger and the second connection line.

19. The method for manufacturing a thin film surface acoustic wave resonator according to claim 18, characterized in that: The first connecting wire, the second connecting wire, the first interdigital electrode and the second interdigital electrode are made of the same material, and a method for forming the first connecting wire, the second connecting wire, the first interdigital electrode and the second interdigital electrode includes: forming a conductive layer on the piezoelectric layer; The conductive layer is patterned to form the first connection line, the second connection line, the first interdigital electrode, and the second interdigital electrode.

20. The method for manufacturing a thin film surface acoustic wave resonator according to claim 18, characterized in that: The first connecting wire, the second connecting wire, the first interdigital electrode, and the second interdigital electrode are made of different materials, and a method for forming the first connecting wire, the second connecting wire, the first interdigital electrode, and the second interdigital electrode includes: forming a first conductive layer on the piezoelectric layer, and patterning the first conductive layer to form the first interdigital electrodes and the second interdigital electrodes; A second conductive layer is formed on the piezoelectric layer, and the second conductive layer is patterned to form the first connecting line and the second connecting line.

21. The method for manufacturing a thin film surface acoustic wave resonator according to claim 20, characterized in that: After forming the first interdigital electrodes and the second interdigital electrodes, forming the first connecting wires and the second connecting wires by using a lift-off process includes: Depositing to form an isolation layer, covering the first interdigital electrodes, the second interdigital electrodes and the piezoelectric layer; Patterning the isolation layer to form a first forming hole; forming the second conductive layer to fill the first forming hole and cover the isolation layer; The second conductive layer on the isolation layer is removed, and the isolation layer is removed to form the first connection line and the second connection line.

22. The method for manufacturing a thin film surface acoustic wave resonator according to claim 20, characterized in that: After forming the first connecting line and the second connecting line, forming the first interdigital electrode and the second interdigital electrode by using a lift-off process, including: Depositing to form an isolation layer, covering the first connecting line, the second connecting line and the piezoelectric layer; Patterning the isolation layer to form a second forming hole; forming the second conductive layer, filling the second forming hole and covering the isolation layer; removing the second conductive layer on the isolation layer and removing the isolation layer; The second conductive layer in the second forming hole is patterned to form the first interdigitated electrode and the second interdigitated electrode.

23. The method for manufacturing a thin film surface acoustic wave resonator according to claim 18, characterized in that: After forming the interdigital electrodes and the connecting wires, the first interconnecting electrodes and the second interconnecting electrodes are formed, wherein the first interconnecting electrodes and / or the second interconnecting electrodes include at least one sub-arch bridge, and a supporting structure is formed between adjacent sub-arch bridges, and the forming method includes: forming a support structure to divide the corresponding gap into a plurality of sub-gaps; forming a sacrificial layer to fill the first gap, the second gap and cover the first interdigital electrode, the second interdigital electrode, the first connecting line and the second connecting line; Etching the sacrificial layer to form a first protrusion and a second protrusion and exposing the interdigital electrodes and connecting wires or the interdigital electrodes, connecting wires and the supporting structure around the corresponding protrusions; Forming corresponding interconnecting electrodes to cover corresponding protrusions and the interdigital electrodes and the connecting wires or the interdigital electrodes, the connecting wires and the supporting structure that are exposed at the periphery of the corresponding protrusions; The first protrusion, the second protrusion and the sacrificial layer are removed.

24. The method for manufacturing a thin film surface acoustic wave resonator according to claim 23, characterized in that: The support structure is made of the same material as the first interdigital electrodes, the second interdigital electrodes and / or the first connecting wires and the second connecting wires, and a method for forming the support structure includes: The support structure is formed when the first interdigital electrodes, the second interdigital electrodes and / or the first connecting lines, the second connecting lines are formed.

25. The method for manufacturing a thin film surface acoustic wave resonator according to claim 23, characterized in that: The support structure is made of a material different from that of the first interdigitated electrodes, the second interdigitated electrodes, the first connecting wires, and the second connecting wires. A method for forming the support structure includes: Before forming the first protrusion and the second protrusion, etching the sacrificial layer to form a third forming hole; Filling the third forming hole to form a supporting material layer; When forming the first protrusion and the second protrusion, etching the support material layer to form the support structure; or, After forming the first protrusion and the second protrusion and before forming the first interconnection electrode and the second interconnection electrode, etching the first protrusion and / or the second protrusion to form a third forming hole; A support structure is formed to fill the third forming hole.

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