Elastic wave device

Abstract

An elastic wave device includes a substrate, a first transmission filter provided on a first main surface of the substrate and having a transmission band of a first frequency band in frequency division duplexing as a passband, a first reception filter provided on the first main surface of the substrate and having a reception band of the first frequency band in the frequency division duplexing as a passband, a second transmission filter provided on the first main surface of the substrate and having a transmission band of a second frequency band in the frequency division duplexing as a passband, a second reception filter provided on the first main surface of the substrate and having a reception band of the second frequency band in the frequency division duplexing as a passband, and a first antenna terminal provided on a second main surface of the substrate, the first transmission filter is provided closer to the first antenna terminal than the second transmission filter, and the first reception filter is provided closer to the first antenna terminal than the second reception filter. Thereby, isolation between frequency bands is ensured to reduce loss.

Description

Technical Field

[0001] This invention relates to an elastic wave device, for example, to a double-duplexer composed of multiple elastic wave filters. Background Technology

[0002] Smartphones and other devices that serve as mobile communication terminals need to communicate in multiple corresponding frequency bands. Therefore, elastic wave devices containing multiple elastic wave filters, multiple duplexers, or quadplexers are used.

[0003] Furthermore, in elastic wave devices, interference between the transmitting and receiving filters must be taken into account, and low loss is required. As described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2019-54354), the design takes into account the interference between multiple filters and places four filters in appropriate positions. Summary of the Invention

[0004] The main problems that this invention aims to solve are described below.

[0005] In the case of an elastic wave device with double duplexer function formed by installing four elastic wave filters on a substrate, interference between the transmitting and receiving filters will cause losses. Furthermore, the inability to completely isolate frequency bands will also cause losses.

[0006] In view of the above-mentioned problems, the present invention aims to provide an elastic wave device that can suppress interference between the transmitting filter and the receiving filter, ensure isolation between frequency bands, and reduce losses.

[0007] The elastic wave device of the present invention includes a substrate, a first transmitting filter disposed on a first main surface of the substrate and using a transmitting band of a first frequency band in frequency division duplexing as the passing band, a first receiving filter disposed on the first main surface of the substrate and using a receiving band of the first frequency band in frequency division duplexing as the passing band, a second transmitting filter disposed on the first main surface of the substrate and using a transmitting band of a second frequency band in frequency division duplexing as the passing band, a second receiving filter disposed on the first main surface of the substrate and using a receiving band of the second frequency band in frequency division duplexing as the passing band, and a first antenna terminal disposed on a second main surface of the substrate. The first transmitting filter is disposed closer to the first antenna terminal than the second transmitting filter, and the first receiving filter is disposed closer to the first antenna terminal than the second receiving filter.

[0008] In one embodiment of the present invention, the second main surface of the substrate is further provided with a second antenna terminal.

[0009] In one embodiment of the present invention, the elastic wave device further includes a first wiring electrically connected to the first antenna terminal, the first transmitting filter, and the first receiving filter, and a second wiring electrically connected to the second antenna terminal, the second transmitting filter, and the second receiving filter, wherein the first wiring and the second wiring do not intersect in a three-dimensional manner.

[0010] In one embodiment of the present invention, the elastic wave device is further provided with an input terminal of the first transmitting filter, an output terminal of the first receiving filter, an input terminal of the second transmitting filter, an output terminal of the second receiving filter, and a grounding terminal on the second main surface of the substrate.

[0011] In one embodiment of the invention, the elastic wave device further includes a metal pattern disposed on a second main surface of the substrate and located between the first antenna terminal and the second antenna terminal.

[0012] In one embodiment of the present invention, the first transmitting filter is configured to be adjacent to the second transmitting filter, and the first receiving filter is configured to be adjacent to the second receiving filter.

[0013] In one embodiment of the present invention, at least one of the first transmitting filter, the second transmitting filter, the first receiving filter, and the second receiving filter is an elastic surface wave filter.

[0014] In one embodiment of the invention, the elastic surface wave filter has a piezoelectric substrate bonded to a support substrate made of high-impedance silicon, gallium arsenide, sapphire, spinel, polycrystalline alumina, or glass.

[0015] In one embodiment of the present invention, at least one of the first transmitting filter, the second transmitting filter, the first receiving filter, and the second receiving filter is a filter using a piezoelectric thin film resonator.

[0016] In one embodiment of the present invention, the piezoelectric thin film resonator has a chip substrate, a piezoelectric film disposed on the chip substrate, a lower electrode, and an upper electrode, wherein the lower electrode and the upper electrode sandwich the piezoelectric film therebetween, and a gap is formed between the lower electrode and the chip substrate.

[0017] According to the present invention, an elastic wave device is provided that can suppress interference between the transmitting filter and the receiving filter, ensure isolation between frequency bands, and reduce losses. Attached Figure Description

[0018] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein:

[0019] Figure 1This is a top view of the elastic wave device in this embodiment.

[0020] Figure 2 This is a cross-sectional view of the elastic wave device in this embodiment.

[0021] Figure 3 This is a schematic diagram of the first main surface of the substrate and the first metal layer.

[0022] Figure 4 This is a schematic diagram of the second metal layer as seen from the first main surface of the substrate into the second metal layer.

[0023] Figure 5 This is a schematic diagram of the third metal layer as seen from the first main surface of the substrate through the third metal layer.

[0024] Figure 6 This is a schematic diagram of the fourth metal layer as seen from the first main surface of the substrate.

[0025] Figure 7 This is a schematic diagram of the fifth metal layer as seen from the first main surface of the substrate.

[0026] Figure 8 This is a schematic diagram of the sixth metal layer as seen from the first main surface of the substrate.

[0027] Figure 9 This is a schematic diagram of the structure of a SAW filter that uses some or all of the filters.

[0028] Figure 10 This is an example top view of the elastic wave component as an elastic surface wave filter.

[0029] Figure 11 This is an example cross-sectional view of an elastic wave component that is a piezoelectric thin film resonator.

[0030] Figure 12 This is an illustration of the effects of an embodiment of the present invention. Detailed Implementation

[0031] The following will describe specific embodiments of the present invention with reference to the accompanying drawings.

[0032] (Example)

[0033] Figure 1 This is a top view of the elastic wave device 1 in this embodiment.

[0034] like Figure 1As shown, the elastic wave device 1 in this embodiment includes a substrate 2, and a first transmitting filter 3, a first receiving filter 5, a second transmitting filter 7 adjacent to the first transmitting filter 3, a second receiving filter 9 adjacent to the first receiving filter 5, a first antenna terminal 11, and a second antenna terminal 13 mounted on the substrate 2. In an alternative embodiment, at least one of the first transmitting filter 3, the second transmitting filter 7, the first receiving filter 5, and the second receiving filter 9 is an elastic surface wave filter. In an alternative embodiment, at least one of the first transmitting filter 3, the second transmitting filter 7, the first receiving filter 5, and the second receiving filter 9 is a filter using a piezoelectric thin film resonator.

[0035] The substrate 2 includes a first main surface and a second main surface opposite to each other. The substrate 2 may be, for example, a multilayer substrate made of resin, or a low-temperature co-fired ceramic (LTCC) multilayer substrate composed of multiple dielectric layers.

[0036] The first main surface of the substrate 2 is provided with the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0037] The first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9 have different and non-overlapping passbands. The first transmitting filter 3 and the first receiving filter 5 allow signals from the transmitting and receiving bands of the first frequency band in the frequency division duplex to pass through, respectively. The second transmitting filter 7 uses the transmitting band of the second frequency band in the frequency division duplex as its passband, and the second receiving filter 9 uses the receiving band of the second frequency band in the frequency division duplex as its passband.

[0038] The first frequency band is, for example, a Long Term Evolution (LTE) band or an Evolved Universal Terrestrial Radio Access (E-UTRA) operating band. The first frequency band is, for example, LTE band 3.

[0039] The second transmitting filter 7 and the second receiving filter 9 allow signals from the transmitting and receiving bands in the second frequency band to pass through, respectively.

[0040] The second frequency band is, for example, LTE frequency band 1.

[0041] refer to Figure 8 The first transmitting filter 3 outputs the signal in the first frequency band of the high-frequency signal input to the input terminal 19 of the first transmitting filter to the first antenna terminal 11, and suppresses other signals.

[0042] The second transmitting filter 7 outputs the signal in the transmission band of the second frequency band from the high-frequency signal input to the input terminal 23 of the second transmitting filter 7 to the second antenna terminal 13, and suppresses other signals.

[0043] The second main surface of the substrate 2 is provided with a first antenna terminal 11 and a second antenna terminal 13.

[0044] The first receiving filter 5 outputs the signal in the receiving band of the first frequency band of the high-frequency signal input to the first antenna terminal 11 to the output terminal 21 of the first receiving filter 5, and suppresses other signals.

[0045] The second receiving filter 9 outputs the signal in the receiving band of the second frequency band of the high-frequency signal input to the second antenna terminal 13 to the output terminal 25 of the second receiving filter 9, and suppresses other signals.

[0046] like Figure 1 As shown, the first transmitting filter 3 is positioned closer to the first antenna terminal 11 than the second transmitting filter 7. Furthermore, the first receiving filter 5 is positioned closer to the first antenna terminal 11 than the second receiving filter 9.

[0047] Although the antenna terminals for the first frequency band and the second frequency band can be shared, in this embodiment, the antenna terminal used for the first frequency band is the first antenna terminal 11, and the antenna terminal used for the second frequency band is the second antenna terminal 13.

[0048] Figure 2 This is a cross-sectional view of the elastic wave device 1 in this embodiment.

[0049] like Figure 2 As shown, the second transmitting filter 7 and the second receiving filter 9 are mounted on the substrate 2 by means of bumps 31.

[0050] The substrate 2 is a multilayer wiring substrate and includes a first metal layer 51, a second metal layer 52, a third metal layer 53, a fourth metal layer 54, a fifth metal layer 55, and a sixth metal layer 56.

[0051] The metal layers 51-56 are alternately stacked with the insulating layers 60 (a plurality of insulating layers 60a-60e). The metal layers 51-56 are electrically connected via through-holes 33 formed in each of the insulating layers 60a-60e.

[0052] The first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9 are mounted opposite each other on the substrate 2 through flip-chip bonding technology, forming a gap.

[0053] The bump 31 can be formed, for example, using gold. The height of the bump 31 is, for example, between 20 μm and 50 μm.

[0054] The sealing portion 35 is formed to cover the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9. The sealing portion 35 can be formed of an insulator such as a synthetic resin, or it can be made of metal. The synthetic resin is, for example, epoxy resin, polyimide, etc., but is not limited to these. Preferably, epoxy resin is used, and the sealing portion 35 is formed by a low-temperature curing process.

[0055] Figure 3 This is a schematic diagram of the first main surface of the substrate 2, and also illustrates the first metal layer 51. The first metal layer 51 is used to mount the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0056] like Figure 3 As shown, the first metal layer 51 is formed on the insulating layer 60a. The insulating layer 60a has a plurality of through holes 33, which allow the first metal layer 51 to be electrically connected.

[0057] like Figure 3 As shown, the first metal layer 51 has a metal pattern 1151 electrically connected to the first antenna terminal 11, a metal pattern 1351 electrically connected to the second antenna terminal 13, a metal pattern 1951 electrically connected to the input terminal 19 of the first transmitting filter 3, a metal pattern 2151 electrically connected to the output terminal 21 of the first receiving filter 5, a metal pattern 2351 electrically connected to the input terminal 23 of the second transmitting filter 7, a metal pattern 2551 electrically connected to the output terminal 25 of the second receiving filter 9, and a metal pattern GND51 electrically connected to the ground potential of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0058] like Figure 3 As shown, the metal pattern 1151 electrically connected to the first antenna terminal 11 has a metal pattern 1151Out electrically connected to the output portion of the first transmitting filter 3, and a metal pattern 1151In electrically connected to the input portion of the first receiving filter 5.

[0059] As shown in this embodiment, interference between transmission and reception can be suppressed by separating the metal pattern 1151Out of the output portion and the metal pattern 1151In of the input portion of the metal pattern 1151 of the first metal layer 51.

[0060] like Figure 3 As shown, the metal pattern 1351 electrically connected to the second antenna terminal 13 has a metal pattern 1351Out electrically connected to the output portion of the second transmitting filter 7, and a metal pattern 1351In electrically connected to the input portion of the second receiving filter 9.

[0061] As shown in this embodiment, interference between transmission and reception can be suppressed by separating the metal pattern 1351Out of the output portion and the metal pattern 1351In of the input portion of the metal pattern 1351 of the first metal layer 51.

[0062] Figure 4 This is a schematic diagram of the second metal layer 52 as seen from the first main surface of the substrate 2. The second metal layer 52 is partially electrically connected to the first metal layer 51 through a plurality of through-holes 33 formed in the insulating layer 60a.

[0063] like Figure 4 As shown, the second metal layer 52 is formed on the insulating layer 60b.

[0064] like Figure 4 As shown, the second metal layer 52 has a metal pattern 1152 electrically connected to the first antenna terminal 11, a metal pattern 1352 electrically connected to the second antenna terminal 13, a metal pattern 1952 electrically connected to the input terminal 19 of the first transmitting filter 3, a metal pattern 2152 electrically connected to the output terminal 21 of the first receiving filter 5, a metal pattern 2352 electrically connected to the input terminal 23 of the second transmitting filter 7, a metal pattern 2552 electrically connected to the output terminal 25 of the second receiving filter 9, and a metal pattern GND52 electrically connected to the ground potential of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0065] Figure 5 This is a schematic diagram of the third metal layer 53 as seen from the first main surface of the substrate 2. The third metal layer 53 is partially electrically connected to the second metal layer 52 through a plurality of through-holes 33 formed in the insulating layer 60b.

[0066] like Figure 5 As shown, the third metal layer 53 is formed on the insulating layer 60c.

[0067] like Figure 5 As shown, the third metal layer 53 has a metal pattern 1153 electrically connected to the first antenna terminal 11, a metal pattern 1353 electrically connected to the second antenna terminal 13, a metal pattern 1953 electrically connected to the input terminal 19 of the first transmitting filter 3, a metal pattern 2153 electrically connected to the output terminal 21 of the first receiving filter 5, a metal pattern 2353 electrically connected to the input terminal 23 of the second transmitting filter 7, a metal pattern 2553 electrically disconnected from the output terminal 25 of the second receiving filter 9, and a metal pattern GND53 electrically connected to the ground potential of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0068] Figure 6 This is a schematic diagram of the fourth metal layer 54 as seen from the first main surface of the substrate 2. The fourth metal layer 54 is partially electrically connected to the third metal layer 53 through a plurality of through-holes 33 formed in the insulating layer 60c.

[0069] like Figure 6 As shown, the fourth metal layer 54 is formed on the insulating layer 60d.

[0070] like Figure 6 As shown, the fourth metal layer 54 has a metal pattern 1154 electrically connected to the first antenna terminal 11, a metal pattern 1354 electrically connected to the second antenna terminal 13, a metal pattern 1954 electrically connected to the input terminal 19 of the first transmitting filter 3, a metal pattern 2154 electrically connected to the output terminal 21 of the first receiving filter 5, a metal pattern 2354 electrically connected to the input terminal 23 of the second transmitting filter 7, a metal pattern 2554 electrically connected to the output terminal 25 of the second receiving filter 9, and a metal pattern GND54 electrically connected to the ground potential of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0071] Figure 7 This is a schematic diagram of the fifth metal layer 55 as seen from the first main surface of the substrate 2. The fifth metal layer 55 is partially electrically connected to the fourth metal layer 54 through a plurality of through-holes 33 formed in the insulating layer 60d.

[0072] like Figure 7 As shown, the fifth metal layer 55 is formed on the insulating layer 60e.

[0073] like Figure 7As shown, the fifth metal layer 55 has a metal pattern 1155 electrically connected to the first antenna terminal 11, a metal pattern 1355 electrically connected to the second antenna terminal 13, a metal pattern 1955 electrically connected to the input terminal 19 of the first transmitting filter 3, a metal pattern 2155 electrically connected to the output terminal 21 of the first receiving filter 5, a metal pattern 2355 electrically connected to the input terminal 23 of the second transmitting filter 7, a metal pattern 2555 electrically connected to the output terminal 25 of the second receiving filter 9, and a metal pattern GND55 electrically connected to the ground potential of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0074] Figure 8 This is a schematic diagram of the sixth metal layer 56 as seen from the first main surface of the substrate 2. The sixth metal layer 56 is partially electrically connected to the fifth metal layer 55 through a plurality of through-holes 33 formed in the insulating layer 60e.

[0075] like Figure 8 As shown, the sixth metal layer 56 has the first antenna terminal 11, the second antenna terminal 13, the input terminal 19 of the first transmitting filter 3, the output terminal 21 of the first receiving filter 5, the input terminal 23 of the second transmitting filter 7, the output terminal 25 of the second receiving filter 9, and a ground terminal 27.

[0076] Furthermore, such as Figure 8 As shown, the sixth metal layer 56 may also have a metal pattern 29. This allows for better isolation between the first antenna terminal 11 and the second antenna terminal 13.

[0077] Here, as Figure 3 The metal pattern 1151 shown is formed by the metal pattern 1151Out, which is electrically connected to the output portion of the first transmitting filter 3, and the metal pattern 1151In, which is electrically connected to the input portion of the first receiving filter 5. Figure 4 The metal pattern 1152 of the second metal layer 52 shown is as follows: Figure 5 The metal pattern 1153 of the third metal layer 53 shown is as follows: Figure 6 The metal pattern 1154 of the fourth metal layer 54 shown is as follows: Figure 7 The metal pattern 1155 of the fifth metal layer 55 shown, and as shown Figure 8 The wiring formed by the first antenna terminal 11 of the sixth metal layer 56 shown is the first wiring.

[0078] Furthermore, such as Figure 3The metal pattern 1351 shown is formed by the metal pattern 1351Out, which is electrically connected to the output portion of the second transmitting filter 7, and the metal pattern 1351In, which is electrically connected to the input portion of the second receiving filter 9. Figure 4 The metal pattern 1352 of the second metal layer 52 shown is as follows: Figure 5 The metal pattern 1353 of the third metal layer 53 shown is as follows: Figure 6 The metal pattern 1354 of the fourth metal layer 54 shown is as follows: Figure 7 The metal pattern 1355 of the fifth metal layer 55 shown, and as shown Figure 8 The wiring formed by the second antenna terminal 13 of the sixth metal layer 56 shown is the second wiring.

[0079] Based on the above Figures 3 to 8 As explained, the first wiring and the second wiring do not intersect in a three-dimensional manner. Because the first wiring and the second wiring do not intersect in a three-dimensional manner, parasitic capacitance caused by the wiring being separated by an insulation layer can be avoided, thus improving the isolation effect between the first frequency band and the second frequency band.

[0080] Next, structural examples of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9 will be described.

[0081] Figure 9 This is a schematic diagram of the structure of a SAW filter that can use some or all of the first transmitting filter 3, the first receiving filter 5, the second transmitting filter 7, and the second receiving filter 9.

[0082] like Figure 9 As shown, an elastic wave component 72 and a wiring pattern 74 are formed on the piezoelectric substrate 70.

[0083] The piezoelectric substrate 70 can be, for example, a piezoelectric single crystal such as lithium tantalate, lithium niobate, or quartz, or a piezoelectric ceramic. Furthermore, the piezoelectric substrate 70 can also be bonded to a support substrate. The support substrate can be, for example, a substrate made of high-resistivity silicon, gallium arsenide, sapphire, spinel, polycrystalline alumina, or glass.

[0084] Figure 10 This is a top view of an example of an elastic surface wave filter, specifically the elastic wave component 72.

[0085] like Figure 10As shown, an IDT (Interdigital Transducer) 72a and a reflector 72b for exciting elastic surface waves are formed on the piezoelectric substrate 70. The IDT 72a has a pair of comb-shaped electrodes 72c arranged facing each other. The comb-shaped electrodes 72c have multiple electrode fingers 72d and multiple busbars 72e connecting the electrode fingers 72d. The reflector 72b is disposed on both sides of the IDT 72a.

[0086] The IDT 72a and reflector 72b are, for example, made of an alloy of aluminum and copper. The IDT 72a and reflector 72b are, for example, thin films with a thickness between 150 nm and 400 nm. The IDT 72a and reflector 72b can also be other metals, such as titanium, palladium, silver, or alloys containing the aforementioned metals, and can be formed from these alloys. Furthermore, the IDT 72a and reflector 72b can also be formed from a stacked metal film composed of multiple stacked metal films.

[0087] To achieve the desired bandpass filter characteristics, the elastic wave component 72 may be appropriately designed using a defective microstrip structure (DMS) or a trapezoidal design.

[0088] The wiring pattern 74 includes wiring that forms an input pad In, an output pad Out, and a ground pad GND. Furthermore, the wiring pattern 74 is electrically connected to the elastic wave assembly 72.

[0089] An insulator 76 is formed on the wiring pattern 74. The insulator 76 may be, for example, made of polyimide. The film thickness of the insulator 76 may be, for example, 1000 nm.

[0090] A second wiring pattern 78 is formed on the insulator 76. The second wiring pattern 78 is formed in a manner that intersects the wiring pattern 74 three-dimensionally through the insulator 76.

[0091] The elastic wave component 72, wiring pattern 74, and second wiring pattern 78 are made of suitable metals or alloys such as silver, aluminum, copper, titanium, and palladium. Furthermore, the aforementioned metal pattern can also be formed by a stacked metal film composed of multiple metal layers. The thickness of the elastic wave component 72, wiring pattern 74, and second wiring pattern 78 is, for example, between 150 nm and 400 nm.

[0092] Figure 11 This is a cross-sectional view of an example of the elastic wave component 72 being a piezoelectric thin film resonator.

[0093] like Figure 11As shown, a piezoelectric film 82 is provided on the chip substrate 80. The piezoelectric film 82 is sandwiched between a lower electrode 84 and an upper electrode 86. A gap 88 is formed between the lower electrode 84 and the chip substrate 80. The lower electrode 84 and the upper electrode 86 excite longitudinal vibration modes along the thickness direction within the piezoelectric film 82.

[0094] The chip substrate 80 is, for example, a semiconductor substrate such as silicon, or it can also be an insulating substrate such as sapphire, alumina, spinel, or glass. The piezoelectric film 82 can be, for example, aluminum nitride. The lower electrode 84 and the upper electrode 86 can be, for example, metals such as ruthenium.

[0095] Figure 12 This is an illustration of the efficacy of an embodiment of the present invention.

[0096] like Figure 12 As shown, the waveform drawn with solid lines represents the attenuation characteristics of an embodiment of the present invention. The waveform drawn with dashed lines represents the attenuation characteristics of a comparative example.

[0097] Here, in the elastic wave device as a comparative example, although the first transmitting filter is located closer to the first antenna terminal than the second transmitting filter, the first receiving filter is located farther away from the first antenna terminal than the second receiving filter. The first wiring that electrically connects the first antenna terminal, the first transmitting filter, and the first receiving filter intersects three-dimensionally with the second wiring that electrically connects the second antenna terminal, the second transmitting filter, and the second receiving filter.

[0098] like Figure 12 As shown, compared with the comparative example, the embodiment of the present invention significantly improves the attenuation characteristics.

[0099] Based on the structure of the present invention described above, an elastic wave device can be provided that can suppress interference between the transmitting filter and the receiving filter, ensure isolation between frequency bands, and reduce losses.

[0100] It should be noted that, of course, the present invention is not limited to the embodiments described above, but also includes all embodiments that can achieve the purpose of the present invention.

[0101] Furthermore, while at least one embodiment has been described above, it should be understood that various changes, modifications, or improvements will readily conceive of by those skilled in the art. These changes, modifications, or improvements are also part of this example and fall within the scope of the invention. It should be understood that the embodiments of the methods or apparatus described herein are not limited to the architecture and arrangement of the constituent components described above or illustrated in the figures. Methods and apparatus can be installed or implemented in other embodiments. The embodiments described are for illustrative purposes only and are not intended to be limiting. Moreover, the descriptions or terms used herein are for illustrative purposes only and are not intended to be limiting. The use of "comprising," "possessing," "having," "including," and variations thereof herein means to include the items listed below, their equivalents, and additional items. The term "or," or any term used in the description of "or," can be interpreted as meaning one, more than one, or all of the descriptive terms. The terms front, back, left, right, top, bottom, up, down, and horizontal are used for convenience of description and are not intended to limit the position and spatial configuration of any constituent component in the invention. Therefore, the above descriptions and figures are merely examples.

Claims

1. An elastic wave device, characterized in that: The elastic wave device includes a substrate, a first transmitting filter disposed opposite to each other on a first main surface of the substrate via flip-chip bonding and using a transmitting band of a first frequency band in frequency division duplexing as the transmitting band, a first receiving filter disposed opposite to each other on the first main surface of the substrate via flip-chip bonding and using a receiving band of a first frequency band in frequency division duplexing as the receiving band, a second transmitting filter disposed opposite to each other on the first main surface of the substrate via flip-chip bonding and using a transmitting band of a second frequency band in frequency division duplexing as the transmitting band, a second receiving filter disposed opposite to each other on the first main surface of the substrate via flip-chip bonding and using a receiving band of a second frequency band in frequency division duplexing as the receiving band, and a first antenna terminal and a second antenna terminal disposed on a second main surface of the substrate. It also includes a first wiring electrically connecting the first antenna terminal, the first transmitting filter, and the first receiving filter, and a second wiring electrically connecting the second antenna terminal, the second transmitting filter, and the second receiving filter. The first wiring and the second wiring pass through the first main surface of the substrate to the second main surface, and the first wiring and the second wiring do not intersect in a three-dimensional manner. The first transmitting filter is positioned closer to the first antenna terminal than the second transmitting filter, and the first receiving filter is positioned closer to the first antenna terminal than the second receiving filter.

2. The elastic wave device according to claim 1, characterized in that: The second main surface of the substrate is also provided with an input terminal of the first transmitting filter, an output terminal of the first receiving filter, an input terminal of the second transmitting filter, an output terminal of the second receiving filter, and a ground terminal.

3. The elastic wave device according to claim 1, characterized in that: It also includes a metal pattern disposed on the second main surface of the substrate and located between the first antenna terminal and the second antenna terminal.

4. The elastic wave device according to claim 1, characterized in that: The first transmitting filter is configured to be adjacent to the second transmitting filter, and the first receiving filter is configured to be adjacent to the second receiving filter.

5. The elastic wave device according to claim 1, characterized in that: At least one of the first transmitting filter, the second transmitting filter, the first receiving filter, and the second receiving filter is an elastic surface wave filter.

6. The elastic wave device according to claim 5, characterized in that: The elastic surface wave filter has a piezoelectric substrate bonded to a support substrate made of high-impedance silicon, gallium arsenide, sapphire, spinel, polycrystalline alumina, or glass.

7. The elastic wave device according to claim 1, characterized in that: At least one of the first transmitting filter, the second transmitting filter, the first receiving filter, and the second receiving filter is a filter using a piezoelectric thin film resonator.

8. The elastic wave device according to claim 7, characterized in that: The piezoelectric thin film resonator has a chip substrate, a piezoelectric film disposed on the chip substrate, a lower electrode, and an upper electrode. The lower electrode and the upper electrode sandwich the piezoelectric film therebetween, and a gap is formed between the lower electrode and the chip substrate.

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