Elastic wave device and electronic module

Abstract

The invention discloses an elastic wave device and an application module thereof, which can attenuate the higher harmonic component of an amplification signal and realize miniaturization at the same time. The elastic wave device includes: a package substrate including a first coil, a second coil, an antenna terminal, a transmission terminal, and a reception terminal; a chip substrate mounted on the package substrate; a plurality of series resonators and a plurality of parallel resonators which are formed on the chip substrate and form a trapezoidal filter; an antenna pad, a transmission pad, a reception pad, and a ground pad formed on the chip substrate; a notch resonator formed on the chip substrate and having a resonant frequency higher than the band of the trapezoidal filter; the first coil is connected with the antenna bonding pad; the second coil is connected with the antenna terminal; the notch resonator is connected to a node between any one of the plurality of parallel resonators and the ground pad.

Description

Technical Field

[0001] The present invention relates to a mobile communication device, and more particularly to an elastic wave device and its application module. Background Art

[0002] Patent Document 1 discloses a matching circuit. The matching circuit is used to amplify an input signal and output an amplified signal to achieve output impedance matching of an amplifier. The matching circuit includes a low-pass filter and a high-pass filter. The ground terminals of the low-pass filter and the high-pass filter are independent of each other, thereby suppressing interference between the low-pass filter and the high-pass filter. Therefore, harmonic components of the amplified signal can be attenuated.

[0003] However, in Patent Document 1, in order to attenuate harmonic components of the amplified signal, a new matching circuit needs to be provided. Therefore, when this matching circuit is applied to an elastic wave device, the volume of the elastic wave device will increase.

[0004] [Patent Document 1] Japanese Unexamined Patent Publication No. 2018-064261. Summary of the Invention

[0005] An object of the present invention is to provide an elastic wave device and its application module capable of miniaturization while attenuating higher harmonic components of an amplified signal.

[0006] To achieve the above object, the present invention provides an elastic wave device, including: a package substrate including a first coil, a second coil, an antenna terminal, a transmission terminal, and a reception terminal; a chip substrate mounted on the package substrate; a plurality of series resonators and a plurality of parallel resonators formed on the chip substrate to constitute a ladder filter; an antenna pad, a transmission pad, a reception pad, and a ground pad formed on the chip substrate; a notch resonator formed on the chip substrate and having a resonance frequency higher than the frequency band of the ladder filter; the first coil is connected to the antenna pad; the second coil is connected to the antenna terminal; the notch resonator is connected to a node between any one of the plurality of parallel resonators and the ground pad.

[0007] In some embodiments, the notch resonator is connected to a node between the first coil and the second coil.

[0008] In some embodiments, the elastic wave device further includes a notch pad formed on the chip substrate and only connected to the notch resonator.

[0009] In some embodiments, the elastic wave device further includes a conductive pad formed on the encapsulation substrate and bumps formed between the conductive pad and the notch pad, and the notch resonator is connected to a node between the first coil and the second coil through the notch pad, the bumps, and the conductive pad.

[0010] In some embodiments, the elastic wave device further includes a capacitor formed on the chip substrate, and the capacitor is connected between the antenna pad and the series resonator closest to the antenna pad among the plurality of series resonators, and is connected to a node between the second coil and the antenna terminal.

[0011] In some embodiments, the elastic wave device further includes a capacitor pad formed on the chip substrate, a conductive pad formed on the encapsulation substrate, and bumps formed between the capacitor pad and the conductive pad, and the capacitor is connected to a node between the second coil and the antenna terminal through the capacitor pad, the bumps, and the conductive pad.

[0012] In some embodiments, the elastic wave device further includes a conductive pad formed on the encapsulation substrate and bumps formed between the conductive pad and the antenna pad, and the first coil is connected to the antenna pad through the conductive pad and the bumps.

[0013] In some embodiments, the plurality of series resonators, the plurality of parallel resonators, and the notch resonator of the elastic wave device function as a transmit filter.

[0014] The present invention also provides an electronic module, including any one of the above elastic wave devices, and an amplifier for amplifying a signal input to the transmit terminal.

[0015] In some embodiments, the electronic module further includes an integrated passive device, a switching circuit, and a low noise amplifier.

[0016] According to the present disclosure, while attenuating the harmonic components of the amplified signal, a miniaturized design of an elastic wave device or the like can be achieved.

[0017] Other features and advantageous effects of the present invention will be described in the subsequent specification, and part of them will become obvious from the specification or will be understood by implementing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application, and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application.

[0019] Figure 1It is a cross-sectional view of the elastic wave device in Example 1.

[0020] Figure 2 It is a view of the chip substrate observed from below after removing the package substrate in the elastic wave device of Example 1.

[0021] Figure 3 It is a schematic diagram of the first example of the elastic wave element in the elastic wave device of Example 1.

[0022] Figure 4 It is a schematic diagram of the second example of the elastic wave element in the elastic wave device of Example 1.

[0023] Figure 5 It is a circuit diagram corresponding to the key part in the elastic wave device of Example 1.

[0024] Figure 6 It is a simulation result diagram of the characteristics of the elastic wave device in Example 1 and the characteristics of the comparative example.

[0025] Figure 7 It is a view of the chip substrate observed from below after removing the package substrate in the elastic wave device of Example 2.

[0026] Figure 8 It is a circuit diagram corresponding to the key part in the elastic wave device of Example 2.

[0027] Figure 9 It is a simulation result diagram of the characteristics of the elastic wave device in Example 2 and the characteristics of the comparative example.

[0028] Figure 10 It is a cross-sectional view of the elastic wave device applied to the module in Example 3.

[0029]

Symbol Explanation

[0030] Embodiment 1 Figure 1 is a cross-sectional view of the surface acoustic wave device in Embodiment 1.

[0031] As Figure 1 shown, the surface acoustic wave device 1 includes a package substrate 2, a chip substrate 3, a plurality of bumps 4, and a sealing portion 5.

[0032] For example, the package substrate 2 may be a multi-layer substrate including resin. For example, the package substrate 2 may be a Low Temperature Co-fired Ceramics (LTCC) multi-layer substrate composed of a plurality of dielectric layers. In some embodiments, the package substrate 2 may be built-in with passive components such as capacitors or coils (such as coil L).

[0033] In Figure 1 , the upper surface of the package substrate 2 is a component mounting surface. A plurality of conductive pads 2A are formed on the upper surface of the package substrate 2. For example, the plurality of conductive pads 2A are made of copper. The lower surface of the package substrate 2 is a mounting surface for mounting to a mother board or the like. A plurality of conductive pads 2B are formed on the lower surface of the package substrate 2. For example, the plurality of conductive pads 2B are made of copper. A plurality of internal conductors 2C are built in the package substrate 2. For example, the plurality of internal conductors 2C are made of copper. Each internal conductor 2C is electrically connected to the corresponding conductive pad 2A and conductive pad 2B. In addition, a first coil L1 and a second coil L2 are built in the package substrate 2. The first coil L1 will be connected to an antenna pad Ant ( Figure 1 not shown in

[0034] ), while the second coil L2 will be connected to an antenna terminal AT mentioned later. The chip substrate 3 is mounted on the package substrate 2. For example, the chip substrate 3 may be formed of a piezoelectric single crystal material such as lithium tantalate, lithium niobate, or quartz. For example, the chip substrate 3 may be formed of a piezoelectric ceramic material. For example, the chip substrate 3 may be formed by bonding a piezoelectric substrate and a support substrate. For example, the support substrate may be made of sapphire, silicon, aluminum oxide, spinel, quartz, or glass.

[0035] For example, on the main surface of the chip substrate 3 ( Figure 1 the lower surface in), a transmit filter and a receive filter are formed.

[0036] The transmit filter is designed to allow an electrical signal in a desired frequency range to pass through. For example, the transmit filter includes a ladder filter composed of a plurality of series resonators and a plurality of shunt resonators.

[0037] The receive filter is designed to allow an electrical signal in a desired frequency range to pass through. For example, the receive filter includes a ladder filter composed of a plurality of series resonators and a plurality of shunt resonators.

[0038] For example, the chip substrate 3 includes a wiring pattern 3A and a plurality of electrodes 3B. For example, the plurality of electrodes 3B are comb-shaped electrode fingers, that is, interdigital transducer (IDT) electrodes. As described later, the chip substrate 3 includes a notch resonator N1 (not shown in Figure 1 ). The notch resonator N1 is connected to a notch pad Nt. The notch pad Nt is connected to a node between the first coil L1 and the second coil L2 through bumps 4 and conductive pads 2A.

[0039] Each of the plurality of bumps 4 is made of a material such as gold, conductive adhesive, or solder. For example, the height of the bumps 4 is 20 μm to 50 μm. For example, each of the plurality of bumps 4 electrically connects the conductive pad 2A and the wiring pattern 3A at a corresponding position.

[0040] The sealing portion 5 hermetically seals the chip substrate 3 together with the package substrate 2 while leaving a gap 6 between the package substrate 2 and the chip substrate 3. For example, the sealing portion 5 is formed of an insulator such as a synthetic resin. The synthetic resin may be a material such as epoxy resin or polyimide.

[0041] Next, in combination with Figure 2 the structure of the chip substrate 3 will be described.

[0042] Figure 2 is a diagram of the chip substrate seen from below after removing the package substrate in the elastic wave device in Embodiment 1.

[0043] For example, Figure 2 the chip substrate 3 shown functions as a duplexer. As shown in Figure 2 , the wiring pattern 3A and a plurality of elastic wave elements 7 are formed on the main surface of the chip substrate 3.

[0044] For example, the wiring pattern 3A is made of a metal or alloy such as silver, aluminum, copper, titanium, or palladium. The wiring pattern 3A can be formed by a stacked structure of multiple layers of metal. For example, the thickness of the wiring pattern 3A is generally 150 nm to 400 nm.

[0045] In Figure 2 the specific embodiment shown, the wiring pattern 3A includes four ground pads Gnd, one antenna pad Ant, one transmission pad Tx, one reception pad Rx, and one notch pad Nt. These pads are used for electrical connection with bumps 4 ( Figure 2 not shown in the figure).

[0046] The plurality of elastic wave elements 7 include a plurality of series resonators S1, S2, S3, S4, a plurality of parallel resonators P1, P2, P3, and one notch resonator N1. These series resonators S1, S2, S3, S4, parallel resonators P1, P2, P3, and notch resonator N1 are electrically connected through the wiring pattern 3A.

[0047] The plurality of series resonators S1, S2, S3, S4, the plurality of parallel resonators P1, P2, P3, and the notch resonator N1 function as a transmission filter TF. Specifically, when a high-frequency electrical signal is input to the transmission pad Tx, the electrical signal will pass through the plurality of series resonators S1, S2, S3, S4, the plurality of parallel resonators P1, P2, P3, and the notch resonator N1. During this process, only the electrical signals in the desired frequency band will reach the antenna pad Ant. Therefore, only the electrical signals in the desired frequency band will be output from the antenna pad Ant.

[0048] Although not shown in detail, the reception filter RF is also similar to the transmission filter TF and is composed of a plurality of series resonators and a plurality of parallel resonators, etc. When a high-frequency electrical signal is input to the antenna pad Ant, the electrical signal will pass through the plurality of series resonators and the plurality of parallel resonators, etc. During this process, only the electrical signals in the desired frequency band will reach the reception pad Rx. Therefore, only the electrical signals in the desired frequency band will be output from the reception pad Rx.

[0049] Next, a first example of the elastic wave element 7 will be described in conjunction with Figure 3 FIG. Figure 3 FIG. 1 shows a first example of the elastic wave element of the elastic wave device in Embodiment 1.

[0050] In Figure 3 FIG. 1, the elastic wave element 7 is a surface acoustic wave (SAW) resonator. As Figure 3 shown in FIG. 1, a pair of IDT electrodes 7A and a pair of reflectors 7B are formed on the main surface of the chip substrate 3. The pair of IDT electrodes 7A and the pair of reflectors 7B are configured to be able to excite elastic surface waves.

[0051] For example, a pair of IDT electrodes 7A and a pair of reflectors 7B are formed of an alloy of aluminum and copper. For example, a pair of IDT electrodes 7A and a pair of reflectors 7B are formed of a suitable metal such as titanium, palladium, silver, or an alloy of these metals. For example, a pair of IDT electrodes 7A and a pair of reflectors 7B are formed of a metal film formed by stacking multiple metal films.

[0052] The IDT electrodes 7A include a plurality of electrode fingers 7D and bus bars 7E. The plurality of electrode fingers 7D are arranged in the long side direction, and the bus bars 7E connect the plurality of electrode fingers 7D together so that they face each other. One side of a pair of reflectors 7B is adjacent to one side of the IDT electrodes 7A, and the other pair of reflectors 7B is adjacent to the other side of the IDT electrodes 7A. For example, a pair of IDT electrodes 7A and a pair of reflectors 7B are formed and patterned by the same process as the wiring pattern 3A (not shown in Figure 3 ).

[0053] Next, a second example of the elastic wave element 7 will be described in conjunction with Figure 4 FIG. Figure 4 FIG. shows a second example of the elastic wave element of the elastic wave device in Embodiment 1.

[0054] In Figure 4 , the elastic wave element 7 is an acoustic thin film resonator. For example, the chip substrate 3 can be a semiconductor substrate such as silicon, or an insulating substrate such as sapphire, alumina, spinel, or glass. A piezoelectric film 7F is provided on the main surface of the chip substrate 3. For example, the piezoelectric film 7F is made of aluminum nitride. A lower electrode 7G and an upper electrode 7H are respectively interposed on both sides of the piezoelectric film 7F. For example, the lower electrode 7G and the upper electrode 7H are made of a metal such as ruthenium. A gap 7J is formed between the lower electrode 7G and the chip substrate 3. In the acoustic thin film resonator, the lower electrode 7G and the upper electrode 7H excite elastic waves in the thickness longitudinal vibration mode within the piezoelectric film 7F.

[0055] Next, the connection relationship of the resonator will be described in conjunction with Figure 5 FIG. Figure 5 FIG. is a circuit diagram corresponding to the key part of the elastic wave device in Embodiment 1.

[0056] As shown in Figure 5 FIG., the package substrate 2 has conductive pads 2B as in Figure 1 , including an antenna terminal AT, a transmission terminal TT, and a reception terminal RT. The antenna terminal AT has the function of exchanging signals with the antenna pad Ant. The transmission terminal TT has the function of outputting an amplified signal to the transmission pad Tx. The reception terminal RT has the function of receiving a signal input from the reception pad Rx.

[0057] In addition, the package substrate 2 further includes a first coil L1 and a second coil L2. The first coil L1 and the second coil L2 are connected in series. The first coil L1 is connected to the antenna pad Ant through the conductive pad 2A and the bump 4. The second coil L2 is connected to the antenna terminal AT.

[0058] In the chip substrate 3, the notch resonator N1 has a resonance frequency higher than the frequency band of the ladder filter. The notch resonator N1 is connected to a node between one of the plurality of parallel resonators and the ground pad Gnd. In Figure 5 the notch resonator N1 is connected to a node between the parallel resonator P2 and the ground pad Gnd.

[0059] In the chip substrate 3, the notch pad Nt is not connected to other resonators other than the notch resonator N1. That is, in the chip substrate 3, the notch pad Nt is only connected to the notch resonator N1. The notch resonator N1 is connected to a node between the first coil L1 and the second coil L2 through the notch pad Nt, the bump 4, and the conductive pad 2A.

[0060] Next, the characteristics of the surface acoustic wave device 1 will be described in conjunction with Figure 6 to illustrate the characteristics of the surface acoustic wave device 1. Figure 6 shows the simulation results of the characteristics of the surface acoustic wave device in Example 1 and the characteristics of the comparative example. Figure 6 The horizontal axis of represents frequency (Frequency, unit is MHz), the vertical axis represents the attenuation amount, A represents the insertion loss, and B represents the frequency characteristics of the wide frequency band.

[0061] In Figure 6 X1 represents the characteristics of the transmit filter TF of the surface acoustic wave device 1 in Example 1 when corresponding to the frequency band 8 (i.e., Band8). X2 represents the characteristics of the comparative example in which the resonator N1 is removed from the transmit filter TF corresponding to X1.

[0062] In Figure 6 A of, m1 represents the lower limit (880 MHz) of the transmit bandwidth of the frequency band 8, and m2 represents the upper limit (915 MHz) of the transmit bandwidth of the frequency band 8. At m1, the insertion loss of X1 is -2.02 dB, while the insertion loss of X2 is -2.35 dB. At m2, the insertion loss of X1 is -2.08 dB, while the insertion loss of X2 is -2.13 dB.

[0063] In Figure 6 B of, m3 represents twice the frequency of m1, that is, the harmonic of 1.76 GHz. At m3, the insertion loss of X1 is -54.04 dB, while the insertion loss of X2 is -48.06 dB.

[0064] As Figure 6As shown, the insertion loss of the elastic wave device 1 in Embodiment 1 is substantially the same as that of the comparative example. In contrast, the elastic wave device 1 in Embodiment 1 can attenuate more high-order harmonic components compared to the comparative example.

[0065] According to the above Embodiment 1, the first coil L1 is provided on the package substrate 2, and the first coil L1 is connected to the antenna pad Ant. The notch resonator N1 is provided on the chip substrate 3 and is connected to a node between one of the plurality of parallel resonators and the ground pad Gnd. In this process, no additional matching circuit is required. Therefore, while attenuating the harmonic components of the amplified signal, miniaturization of the elastic wave device 1 can be achieved, thereby reducing the cost of the elastic wave device 1.

[0066] In addition, the notch resonator N1 can also be directly connected to the ground pad Gnd. In this case, miniaturization of the elastic wave device 1 can also be achieved while attenuating the high-order harmonic components of the amplified signal.

[0067] In addition, when using a matching circuit with a low-pass filter and a notch filter, due to the low Q value of the coil and capacitor, the characteristics of the transmit filter and receive filter of the duplexer deteriorate. In contrast, the elastic wave device 1 according to Embodiment 1 can obtain a duplexer capable of suppressing the degradation of the performance of the transmit filter and receive filter.

[0068] In addition, the notch pad Nt is only connected to the notch resonator N1. In addition, the second coil L2 is connected to the antenna terminal AT. In addition, the notch resonator N1 is connected to a node between the first coil L1 and the second coil L2. Therefore, the high-order harmonic part of the amplified signal can be attenuated more effectively.

[0069] Embodiment 2 Figure 7 FIG. is a diagram of the chip substrate seen from below after removing the package substrate for the elastic wave device in Embodiment 2. It should be noted that the same or corresponding parts as those in Embodiment 1 are denoted by the same reference numerals, and thus the description of these parts is omitted.

[0070] As Figure 7 shown, the chip substrate 3 of Embodiment 2 has an increased capacitor C1 and capacitor pad Cp compared to the chip substrate 3 of Embodiment 1.

[0071] Next, the connection relationship between the resonator and the capacitor C1 will be described in conjunction with Figure 8 FIG. Figure 8 FIG. is a circuit diagram corresponding to the key part of the elastic wave device in Embodiment 2.

[0072] As Figure 8As shown, the capacitor C1 is connected between the antenna pad Ant and the series resonator S4 closest to the antenna pad among the plurality of series resonators. The capacitor C1 is connected to the node between the second coil L2 and the antenna terminal AT through the capacitor pad Cp, the bump 4, and the conductive pad 2A.

[0073] Next, the characteristics of the surface acoustic wave device 1 and the comparative example will be described in combination with Figure 9 the description. Figure 9 The simulation results between the characteristics of the surface acoustic wave device in Embodiment 2 and the characteristics of the comparative example are shown. Figure 9 The horizontal axis represents the frequency, and the vertical axis represents the attenuation amount, where A represents the insertion loss, and B represents the frequency characteristics of the wideband.

[0074] In Figure 9 X3 represents the characteristics of the transmit filter TF of the surface acoustic wave device 1 in Embodiment 2 when configured to correspond to the frequency band 8. X4 represents the characteristics of the comparative example obtained by removing the notch resonator N1 and the capacitor C1 from the transmit filter TF corresponding to X3.

[0075] In Figure 9 In A of, m1 represents the lower limit of the transmit frequency band of the frequency band 8 (880 MHz), and m2 represents the upper limit of the transmit frequency band of the frequency band 8 (915 MHz). At m1, X3 is -2.16 dB, and X4 is -2.35 dB. At m2, X3 is -2.34 dB, and X4 is -2.13 dB.

[0076] In Figure 9 In B of, m3 represents the second harmonic of twice the frequency of m1, that is, 1.76 GHz. m4 represents the third harmonic of three times the frequency of m1, that is, 2.64 GHz. At m3, X3 is -59.75 dB, and X4 is -48.06 dB. At m4, X3 is -61.74 dB, and X4 is -52.46 dB.

[0077] As Figure 9 shown, the insertion loss of the surface acoustic wave device 1 in Embodiment 2 is almost the same as that of the comparative example. In contrast, the surface acoustic wave device 1 in Embodiment 2 has a stronger attenuation effect on the higher harmonics of the second and third harmonics compared to the comparative example.

[0078] In the above Embodiment 2, the capacitor C1 is connected between the antenna pad Ant and the series resonator S4 closest to the antenna pad among the plurality of series resonators. The capacitor C1 is connected to the node between the second coil L2 and the antenna terminal AT. Therefore, the higher harmonics of the second and third harmonics of the amplified signal can be attenuated more effectively.

[0079] Embodiment 3 Figure 10Shows a cross-sectional view of the elastic wave device module applicable in Embodiment 3. It should be noted that the same or corresponding parts in Embodiment 1 or Embodiment 2 have been marked with the same reference signs, and the explanation of this part will be omitted.

[0080] In Figure 10 , the module 100 includes a wiring substrate 101, an integrated circuit component 102, an elastic wave device 1, a coil 103, and a sealing portion 104.

[0081] The wiring substrate 101 is the same as the package substrate 2 in Embodiment 1. The integrated circuit component 102 is mounted inside the wiring substrate 101. The integrated circuit component 102 includes a power amplifier (PA), a switching circuit, and a low-noise amplifier. The elastic wave device 1 is mounted on the main surface of the wiring substrate 101. The coil 103 is mounted on the main surface of the wiring substrate 101, and the coil 103 is used to achieve impedance matching. For example, the coil 103 is an Integrated Passive Device (abbreviated as IPD). The sealing portion 104 encapsulates a plurality of electronic components including the elastic wave device 1.

[0082] In this module, the power amplifier (PA) has the function of amplifying the signal input to the transmission terminal TT of the elastic wave device 1.

[0083] According to the above Embodiment 3, the module 100 includes the elastic wave device 1. The power amplifier (PA) can amplify the signal input to the transmission terminal TT of the elastic wave device 1. Therefore, while suppressing the high-order harmonic components in the amplified signal, miniaturization of the module 100 can be achieved.

[0084] Although multiple aspects of at least one embodiment have been described, it should be understood that various modifications, corrections, and improvements can be easily conceived by those skilled in the art. These modifications, corrections, and improvements are regarded as part of the present invention and are within the scope of the present invention.

[0085] It should be understood that the embodiments of the methods and devices described herein are not limited to the detailed applications of the structures and arrangements of the constituent elements mentioned in the above description or exemplified in the drawings. The methods and devices can be implemented in other embodiments and can be implemented or executed in various ways. Specific implementation examples are given only as examples and are not intended to be limiting.

[0086] The expressions and terms used in the present invention are for illustrative purposes only and should not be regarded as limiting. The use of "comprising", "having", "owning", "including" and variants of these words herein means including the items listed below and their equivalents or additional items.

[0087] References to "or" are intended to be understood as either term used, which may refer to one, more than one, or all of the recited terms.

[0088] References to directions such as front and back, left and right, top and bottom, horizontal and vertical, inside and outside, etc. are for convenience of description. These references do not limit the components of the present invention to any particular position or spatial orientation. Therefore, the above description and illustration are merely examples.

Claims

1. An elastic wave device, characterized in that: include: A packaging substrate comprising a first coil, a second coil, an antenna terminal, a transmitting terminal and a receiving terminal; a chip substrate mounted on the packaging substrate; A plurality of series resonators and a plurality of parallel resonators formed on the chip substrate constitute a ladder filter; An antenna pad, a transmitting pad, a receiving pad and a ground pad are formed on the chip substrate; a notch resonator formed on the chip substrate and having a resonance frequency higher than a frequency band of the ladder filter; The first coil is connected to the antenna pad; The second coil is connected to the antenna terminal; The trap resonator is connected to a node between any one of the plurality of parallel resonators and the ground pad.

2. The elastic wave device according to claim 1, characterized in that: The trap resonator is connected to a node between the first coil and the second coil.

3. The elastic wave device according to claim 2, characterized in that: The chip further includes a trap pad formed on the chip substrate and connected only to the trap resonator.

4. The elastic wave device according to claim 3, characterized in that: It also includes a conductive pad formed on the packaging substrate, and a bump formed between the conductive pad and the trap pad, and the trap resonator is connected to a node between the first coil and the second coil through the trap pad, the bump and the conductive pad.

5. The elastic wave device according to claim 1, characterized in that: Also included is a capacitor formed on the chip substrate, the capacitor being connected between the antenna pad and a series resonator closest to the antenna pad among the plurality of series resonators and being connected to a node between the second coil and the antenna terminal.

6. The elastic wave device according to claim 5, characterized in that: It also includes a capacitor pad formed on the chip substrate, a conductive pad formed on the packaging substrate, and a bump formed between the capacitor pad and the conductive pad. The capacitor is connected to the node between the second coil and the antenna terminal through the capacitor pad, the bump, and the conductive pad.

7. The elastic wave device according to claim 1, characterized in that: It also includes a conductive pad formed on the packaging substrate and a bump formed between the conductive pad and the antenna pad, and the first coil is connected to the antenna pad through the conductive pad and the bump.

8. The elastic wave device according to claim 1, characterized in that: The plurality of series resonators, the plurality of parallel resonators, and the notch resonator function as a transmission filter. 9 . An electronic module comprising the elastic wave device according to claim 1 , and an amplifier for amplifying a signal input to the transmission terminal.

10. The module according to claim 9, characterized in that Also included are integrated passive components, switching circuits and low noise amplifiers.

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