KR20180016295A - High-frequency module - Google Patents

Abstract

The present invention provides a high frequency module capable of realizing both of low loss and low noise. The high frequency module (1) comprises: a longitudinally coupled surface acoustic wave filter (10); and a low noise amplifier (20) connected to the surface acoustic wave filter (10). Input impedance and output impedance of the surface acoustic wave filter (10) connected to the low noise amplifier (20) are different. In a Smith chart, the output impedance in a passing band of the surface acoustic wave filter (10) exists in a region between first output impedance which is the output impedance of the surface acoustic wave filter (10) when a gain of the low noise amplifier (20) becomes maximum and second output impedance which is the output impedance of the surface acoustic wave filter (10) when a noise index of the low noise amplifier (20) becomes minimum.

Description

[0001] HIGH-FREQUENCY MODULE [0002]

The present invention relates to a high frequency module.

2. Description of the Related Art Conventionally, as a circuit module of a mobile communication device, a high frequency module using a surface acoustic wave (SAW) filter has been developed. With the recent widening of the communication frequency band, the reception circuit module is required to have low loss and low noise in order to improve the reception sensitivity of the high frequency module. Therefore, in the high-frequency module, other components are provided at the rear end or the front end of the surface acoustic wave filter (see, for example, Patent Document 1).

In the high frequency module described in Patent Document 1, a low noise amplifier (LNA) is connected to the rear end of the surface acoustic wave filter. Generally, in order to improve the noise characteristic in the high-frequency module, the impedance (output impedance) at the output terminal of the SAW filter at the side connected to the low noise amplifier matches the impedance (input impedance) at the input end of the low noise amplifier , And the output impedance of the surface acoustic wave filter is adjusted.

Adjustment of the output impedance of the surface acoustic wave filter is generally performed by changing the width of the interdigital transducer (IDT) electrode in the resonator constituting the surface acoustic wave filter or the number of electrode fingers in the IDT electrode.

Japanese Patent Application Laid-Open No. 2008-301223

However, when the output impedance of the surface acoustic wave filter is adjusted by changing the crossing width of the IDT electrode, when the crossing width is large, the resistance of the electrode finger constituting the IDT electrode becomes large. Further, when the cross width is small, diffraction loss occurs in the IDT electrode, so that the signal loss becomes large. Therefore, when the crossing width of the IDT electrode is changed to reduce the noise of the surface acoustic wave filter, it is difficult to reduce the loss of the high frequency module.

When the output impedance of the surface acoustic wave filter is adjusted by changing the number of the electrode fingers of the IDT electrode, when the number of the electrode fingers is large, the resonance mode interval necessary for forming the frequency band of the surface acoustic wave filter becomes narrow Therefore, the pass band width of the surface acoustic wave filter becomes narrow. Further, when the number of the electrode fingers is small, the interval of the resonance mode is widened, the characteristics of the voltage standing wave ratio (VSWR) deteriorate, and the signal loss becomes large. Therefore, even when the number of the electrode fingers of the IDT electrode is changed to reduce the noise of the surface acoustic wave filter, it is difficult to reduce the loss of the high frequency module.

In view of the above problems, it is an object of the present invention to provide a high frequency module capable of realizing both low loss and low noise.

According to an aspect of the present invention, there is provided a high frequency module comprising: a longitudinally coupled surface acoustic wave filter having a plurality of resonators; and a high frequency signal filter connected to the surface acoustic wave filter, Wherein the input impedance and the output impedance of the surface acoustic wave filter connected to the low noise amplifier are different from each other, and in the Smith chart, the output impedance in the pass band of the surface acoustic wave filter is the low noise Between the first output impedance which is the output impedance of the surface acoustic wave filter when the gain of the amplifier becomes the maximum and the second output impedance which is the output impedance of the surface acoustic wave filter when the noise figure of the low noise amplifier becomes the minimum Lt; / RTI >

Thereby, in the Smith chart, between the output impedance of the surface acoustic wave filter when the gain of the low-noise amplifier becomes maximum and the output impedance of the surface acoustic wave filter when the noise figure of the low-noise amplifier becomes the minimum, Since the output impedance of the filter is adjusted, it is possible to realize both the reduction in the loss and the reduction in the noise of the surface acoustic wave filter and the high frequency module.

The surface acoustic wave filter may have an electrode parameter for adjusting the output impedance in the pass band of the surface acoustic wave filter to exist in the region in the Smith chart.

Thereby, by adjusting the electrode parameters in the surface acoustic wave filter, it is possible to realize both the reduction in the loss and the reduction in the noise.

The IDT electrode of at least one of the resonators connected to the output terminal of the surface acoustic wave filter may have an extraction electrode, and the electrode parameter may be an arbitrary number of the extraction electrodes.

Thereby, the capacitive impedance of the resonator formed with the extraction electrode can be adjusted by adjusting the number of extraction electrodes. Therefore, the output impedance of the surface acoustic wave filter can be adjusted.

The lead electrode may be formed at a central portion of the resonator.

Thus, by forming the lead electrode in the central portion of the resonator with less influence on the resonance mode, it is possible to reduce the loss of the surface acoustic wave filter.

The lead electrode may be formed in a range of 46% of the center portion of the resonator.

Thus, by forming the lead electrode in a predetermined region in the central portion of the resonator with less influence on the resonance mode, it is possible to further reduce the loss of the surface acoustic wave filter.

The IDT electrode of the resonator connected to the output terminal of the surface acoustic wave filter is divided in the cross width direction, and the electrode parameter may be a division number in the cross width direction of the IDT electrode.

Thereby, the output impedance of the surface acoustic wave filter can be adjusted without being affected by the diffraction hand of the IDT electrode divided by the resonator.

It is preferable that the electrode parameter includes a first main wavelength which is an average value of the main wavelength of the resonator connected to the input terminal of the surface acoustic wave filter and a second main wavelength which is an average value of the main wavelength of the resonator connected to the output terminal of the surface acoustic wave filter And the first main wavelength and the second main wavelength may be different from each other.

Thereby, the output impedance of the surface acoustic wave filter can be changed from 50?. Therefore, the output impedance of the surface acoustic wave filter can be changed to match the impedance of the surface acoustic wave filter and the low noise amplifier.

In the resonator connected to the output terminal of the surface acoustic wave filter with respect to the first main wavelength which is an average value of the main wavelength of the resonator connected to the input terminal of the surface acoustic wave filter, Which is the average value of the main wavelength of the main wave equipment, and the main wave equipment may be 1.01 or more.

Thereby, the output impedance of the surface acoustic wave filter can be made higher than 50?. Therefore, it is possible to further match the impedances of the surface acoustic wave filter and the low noise amplifier.

The electrode parameter may be the main duty of the resonator connected to the output terminal of the surface acoustic wave filter, and the main duty may be larger than 0.55 and smaller than 0.75.

Thereby, the output impedance of the surface acoustic wave filter can be increased or decreased by increasing or decreasing the main duty of the resonator connected to the output terminal of the surface acoustic wave filter. Further, since the output impedance of the surface acoustic wave filter can be changed from 50 OMEGA, the output impedance of the surface acoustic wave filter can be changed to match the impedance between the surface acoustic wave filter and the low noise amplifier.

In the above-described surface acoustic wave filter, the wiring between the IDT electrode of the resonator connected to the output terminal of the surface acoustic wave filter and the output terminal of the surface acoustic wave filter may be formed on the interlayer insulating film formed on the substrate.

Thus, by reducing the capacitive coupling between the wiring and the substrate, the output impedance of the surface acoustic wave filter can be adjusted to the inductive impedance.

The IDT electrode of the resonator connected to the output terminal of the SAW filter has a first electrode layer formed on the substrate and a second electrode layer formed on the first electrode layer. The wiring may include the first electrode layer and the second electrode layer.

As a result, the reduction in capacitance coupling between the wiring and the substrate is small, so that the output impedance of the surface acoustic wave filter can be adjusted to a small adjustment amount with an inductive impedance.

The interconnection at the position where the interlayer insulating film is disposed may have the interlayer insulating film instead of the first electrode layer.

Thus, the capacitive coupling between the wiring and the substrate can be further reduced, so that the output impedance of the surface acoustic wave filter can be more adjusted to the inductive side.

According to the present invention, it is possible to provide a high frequency module capable of realizing both low loss and low noise.

1 is a conceptual diagram showing a configuration of a high frequency module according to the first embodiment.
2A is a schematic diagram showing the configuration of a surface acoustic wave filter according to the first embodiment.
FIG. 2B is a schematic view showing the basic configuration of the surface acoustic wave filter structure shown in FIG. 2A.
Fig. 3 is a schematic view showing a configuration of a general surface acoustic wave filter. Fig. 3 (a) is a plan view and Fig. 3 (b) is a sectional view taken in a direction indicated by an arrow in a chain line shown in Fig.
4 is a schematic diagram showing the details of the SAW filter configuration according to the first embodiment.
5 is a schematic view showing the configuration of a resonator when the number of extraction electrodes is one in the surface acoustic wave filter according to the first embodiment;
6A is a schematic view showing the configuration of a resonator when two extraction electrodes are provided in the surface acoustic wave filter according to the first embodiment.
6B is a schematic view showing a configuration of a resonator when three outgoing electrodes are provided in the surface acoustic wave filter according to the first embodiment;
7 is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter according to the first embodiment.
8 is a schematic view showing a configuration of a resonator for explaining a position where a lead electrode is formed in the surface acoustic wave filter according to the first embodiment;
9 is a diagram showing the relationship between the position where the lead electrode is formed and the signal loss on the output terminal side of the surface acoustic wave filter in the surface acoustic wave filter according to the first embodiment.
10 is a diagram for explaining a method of adjusting the output impedance of the surface acoustic wave filter according to the first embodiment.
11A is a diagram showing the pass characteristics of the surface acoustic wave filter when the output impedance of the surface acoustic wave filter according to the first embodiment is adjusted.
Fig. 11B is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter when the output impedance of the surface acoustic wave filter according to the first embodiment is adjusted. Fig.
11C is a diagram showing the pass characteristics of the high frequency module when the output impedance of the surface acoustic wave filter according to the first embodiment is adjusted.
12A is a schematic view showing a configuration of a surface acoustic wave filter according to the second embodiment.
12B is a schematic view showing a configuration of a resonator in the surface acoustic wave filter according to the second embodiment.
13 is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter according to the second embodiment.
14A is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter according to the second embodiment.
14B is a diagram showing noise characteristics on the output terminal side of the entire high-frequency module having the surface acoustic wave filter according to the second embodiment.
15 is a schematic view showing the configuration of a surface acoustic wave filter according to the third embodiment.
16A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter according to the third embodiment.
16B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter according to the third embodiment.
17 is a schematic view showing another configuration of a surface acoustic wave filter according to the third embodiment.
18A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter of another configuration related to the third embodiment.
18B is a diagram showing the transmission characteristics on the output terminal side of the SAW filter of another configuration according to the third embodiment.
19 is a schematic diagram showing the configuration of a surface acoustic wave filter according to Embodiment 4 of the present invention.
20A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter according to the fourth embodiment.
20B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter according to the fourth embodiment.
21 is a schematic diagram showing another configuration of a surface acoustic wave filter according to the fourth embodiment.
22A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter according to the fourth embodiment.
22B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter according to the fourth embodiment.
23 is a schematic view showing the configuration of a surface acoustic wave filter according to Embodiment 5. [
24A is a cross-sectional view showing the configuration of the surface acoustic wave filter shown in FIG. 23 in the BB line.
FIG. 24B is a cross-sectional view showing the configuration of the surface acoustic wave filter shown in FIG. 23 in the CC line. FIG.
25A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter of another configuration according to the fifth embodiment.
25B is a diagram showing noise characteristics on the output terminal side of the surface acoustic wave filter according to the fifth embodiment.
26 is a cross-sectional view showing another configuration of a surface acoustic wave filter of the surface acoustic wave filter shown in Fig.

Hereinafter, an embodiment of the present invention will be described. In addition, all of the embodiments described below represent one preferred embodiment of the present invention. Therefore, numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, and the like appearing in the following embodiments are merely examples and do not limit the present invention. Therefore, among the constituent elements in the following embodiments, constituent elements which are not described in the independent claims indicating the highest concept of the present invention will be described as arbitrary constituent elements.

In addition, each drawing is a schematic diagram and is not necessarily shown strictly. In each drawing, substantially the same components are denoted by the same reference numerals, and redundant descriptions are omitted or simplified. In the illustrated electrode structure, in order to facilitate understanding of the present invention, the number of electrode fingers in the resonator and the reflector is shown to be smaller than the number of actual electrode fingers. In the illustrated Smith chart, the portion of the output impedance in the pass band of the surface acoustic wave filter is indicated by a bold line.

(Embodiment 1)

Hereinafter, Embodiment 1 will be described with reference to Figs. 1 to 11C.

[One. Configuration of high frequency module]

First, the configuration of the high-frequency module 1 according to the present embodiment will be described. 1 is a conceptual diagram showing the configuration of the high-frequency module 1 according to the present embodiment.

1, the high-frequency module 1 according to the present embodiment includes a surface acoustic wave filter 10 and a low-noise amplifier 20. The surface- One end of the surface acoustic wave filter 10 is connected to the input terminal IN of the high frequency module 1 and the other end is connected to the low noise amplifier 20. [ The low-noise amplifier 20 is an amplifier that amplifies weak propagation after reception as much as possible without increasing noise.

The input impedance in the surface acoustic wave filter 10 refers to the impedance of the surface acoustic wave filter 10 when the surface acoustic wave filter 10 is viewed from the input terminal IN side of the high frequency module 1. [ That is, it refers to the SAW input side impedance indicated by an arrow in Fig. The output impedance refers to the impedance of the surface acoustic wave filter 10 when the surface acoustic wave filter 10 is viewed from a terminal (not shown) on the side to which the low noise amplifier 20 to which the high frequency signal is output is connected. That is, it refers to the SAW output side impedance indicated by an arrow in Fig. The surface acoustic wave filter 10 connected to the low noise amplifier 20 has an input impedance and an output impedance different from each other.

[2. Configuration of Surface Acoustic Wave Filter]

2A is a schematic diagram showing the configuration of a surface acoustic wave filter according to the present embodiment. Fig. 2B is a schematic diagram showing the basic configuration of the surface acoustic wave filter structure shown in Fig. 2A.

The surface acoustic wave filter 10 is a longitudinally coupled surface acoustic wave filter. 2A, a surface acoustic wave filter 10 includes a resonator 13, a resonator 14 and a resonator 15, and a reflector 15 between the input terminal 11 and the output terminal 12, (16) and a reflector (17). The resonator 13, the resonator 14 and the resonator 15 are arranged in this order from the reflector 16 side to the reflector 17 side.

As shown in Fig. 2B, the resonator 13 has a structure in which two IDT electrodes 130a and 130b are combined. The IDT electrode 130a of the resonator 13 is connected to the input terminal 11. The IDT electrode 130b is connected to the ground. Similarly, the resonator 15 has a structure in which two IDT electrodes 150a and 150b are combined. The IDT electrode 150a of the resonator 15 is connected to the input terminal 11. The IDT electrode 150b is connected to the ground.

The resonator 14 disposed between the resonator 13 and the resonator 15 has a structure in which two IDT electrodes 140a and 140b are combined. The IDT electrode 140a of the resonator 14 is connected to the ground. The IDT electrode 140b is connected to the output terminal 12. The configuration of the resonator 14 will be described later in detail.

The reflector 16 includes a plurality of bus bar electrodes 16a and a plurality of bus bar electrodes 16b and a plurality of bus bar electrodes 16a and a plurality of bus bar electrodes 16b. And an electrode finger 16c connected at its both ends to the bus bar electrode 16b. A plurality of bus bar electrodes 17a and a plurality of bus bar electrodes 17b are provided between the bus bar electrodes 17a and the bus bar electrodes 17b, And an electrode finger 17c connected at both ends to the bus bar electrode 17b.

Here, the configuration of the resonator will be described in more detail by using a general resonator 100. FIG.

Fig. 3 is a schematic view showing the configuration of a general surface acoustic wave filter. Fig. 3 (a) is a plan view, and Fig. 3 (b) is a sectional view taken along the chain line shown in Fig.

As shown in Figs. 3A and 3B, the resonator 100 includes a piezoelectric substrate 123, IDT electrodes 101a and IDT electrodes 101b having a comb shape.

The piezoelectric substrate 123 includes, for example, a single crystal of LiNbO ₃ cut at a predetermined cut angle. In the piezoelectric substrate 123, surface acoustic waves propagate in a predetermined direction.

3A, a pair of opposing IDT electrodes 101a and IDT electrodes 101b are formed on the piezoelectric substrate 123. As shown in Fig. The IDT electrode 101a includes a plurality of electrode fingers 110a parallel to each other and a bus bar electrode 111a connecting a plurality of electrode fingers 110a. The IDT electrode 101b includes a plurality of electrode fingers 110b parallel to each other and a bus bar electrode 111b connecting a plurality of electrode fingers 110b. The IDT electrode 101a and the IDT electrode 101b are arranged such that a plurality of electrode fingers 110b of the IDT electrode 101b are disposed between each of the plurality of electrode fingers 110a of the IDT electrode 101a Respectively.

The IDT electrode 101a and the IDT electrode 101b have a structure in which the adhesion layer 124a and the main electrode layer 124b are laminated as shown in Fig. 3 (b).

The adhesion layer 124a is a layer for improving the adhesion between the piezoelectric substrate 123 and the main electrode layer 124b, and for example, NiCr is used as the material.

As the material of the main electrode layer 124b, for example, Pt is used. The main electrode layer 124b may be a single layer structure including one layer or a laminated structure in which a plurality of layers are laminated.

The protective layer 125 is formed so as to cover the IDT electrode 101a and the IDT electrode 101b. The protective layer 125 is intended to protect the main electrode layer 124b from the external environment, to adjust the frequency-temperature characteristic, to increase moisture resistance, and the like. The protective layer 125 is, for example, a film mainly composed of silicon dioxide. The protective layer 125 may have a single-layer structure or a stacked structure.

The material constituting the adhesion layer 124a, the main electrode layer 124b and the protective layer 125 is not limited to the above-described materials. The IDT electrode 101a and the IDT electrode 101b do not have to have the above-described laminated structure. The IDT electrode 101a and the IDT electrode 101b may be made of a metal or an alloy such as Ti, Al, Cu, Pt, Au, Ag, Pd or the like, May include a plurality of stacked layers. In addition, the protective layer 125 may not be formed.

Here, the design parameters of the IDT electrode 101a and the IDT electrode 101b will be described. The lambda shown in FIG. 3B is referred to as a pitch of the electrode finger 110a and the electrode finger 110b constituting the IDT electrode 101a and the IDT electrode 101b. The main wavelength of the surface acoustic wave filter is defined by the pitch lambda of a plurality of electrode fingers 110a and electrode fingers 110b constituting the IDT electrode 101a and the IDT electrode 101b. The main wavelength refers to the wavelength in the main pitch region of the IDT electrodes 101a and 101b to be described later.

Specifically, the pitch? Refers to the length from the center of the width of one electrode finger to the center of the width of the other electrode finger in the adjacent electrode finger connected to the same bus bar electrode. For example, in FIG. 3 (b), from the center of the width of one electrode finger 110a connected to the bus bar electrode 111a, the bus bar electrode 111a to which the one electrode finger 110a is connected And is a length up to the center of the width of another electrode finger 110a adjacent to one electrode finger 110a.

3B shows the width of the electrode finger 110a of the IDT electrode 101a and the electrode finger 110b of the IDT electrode 101b in the resonator 100. In the resonator 100, 3B indicates the distance between the electrode finger 110a and the electrode finger 110b. 3 (a) is an intersection width of the IDT electrode 101a and the IDT electrode 101b, and the electrode finger 110a of the IDT electrode 101a and the electrode finger of the IDT electrode 101b Quot; refers to the length of the electrode finger where the electrode finger 110b is overlapped. The logarithm refers to the number of electrode fingers 110a or electrode fingers 110b.

The duty of the IDT electrodes 101a and 101b refers to the ratio of the width of the electrode fingers 110a and 110b to the repetitive pitch lambda of the electrode fingers 110a and 110b. More specifically, the duty of the IDT electrodes 101a and 101b is defined as W, where W is the width of the electrode fingers 110a and 110b of the IDT electrodes 101a and 101b, (W + S) when the distance between the electrode finger 110a and the electrode finger 110b is S, respectively. The main duty refers to the duty in the main pitch region of the IDT electrodes 101a and 101b to be described later.

The center portion of the resonator 100 refers to a portion of the IDT electrode 101a and the IDT electrode 101b of the resonator 100 from a center in the propagation direction of the surface acoustic wave within a predetermined range. The predetermined range is, for example, 46% of the center portion of the resonator 100 as will be described later in detail. The predetermined range may be appropriately changed.

The structure of the resonator 100 is not limited to the structure shown in Figs. 3 (a) and 3 (b). The structure of the surface acoustic wave filter 10 according to the present embodiment is not limited to the above-described structure.

Hereinafter, the configuration of the resonator 14 will be described in more detail.

4 is a schematic view showing the details of the configuration of the surface acoustic wave filter 10a according to the embodiment. 5 is a schematic view showing the configuration of the resonator 14a when the number of drawing electrodes is one in the surface acoustic wave filter 10a according to the present embodiment. 6A is a schematic view showing the configuration of the resonator 14a when two drawing electrodes are provided. Fig. 6B is a schematic view showing the configuration of the resonator 14a when three drawing electrodes are provided. Fig.

As shown in Fig. 4, the resonator 14a has a structure in which two IDT electrodes 140a and 140b are combined. The IDT electrode 140a has a bus bar electrode 141a and a plurality of electrode fingers 142a one end of which is connected to the bus bar electrode 141a. Similarly, the IDT electrode 140b has a bus bar electrode 141b and a plurality of electrode fingers 142b connected at one end to the bus bar electrode 141b. The pitch of the electrode fingers 142a and 142b is narrower than the pitch of the electrode fingers of the center portion except the vicinity of both ends in the vicinity of both ends of the resonator 14a. In addition, a region where the pitch of the electrode finger is narrow is referred to as a narrow pitch region, and other regions are referred to as a main pitch region. The number of electrode fingers 142a and 142b in the narrow pitch region is, for example, 3.

The resonator 14a has the lead-out electrode 143 on the IDT electrode 140a connected to the ground. 5 (a), the lead-out electrode 143 includes a plurality of electrode fingers 142b connected to the bus bar electrode 141b of the IDT electrode 140b connected to the output terminal 12 As shown in FIG. 5 (b), is connected to the bus bar electrode 141a of the IDT electrode 140a connected to the ground instead of the bus bar electrode 141b.

In the case where one lead electrode 143 is formed, as shown in Fig. 5B, in the IDT electrode 140a, between two electrode fingers 142a connected to the bus bar electrode 141a The extraction electrode 143a is formed. Therefore, three electrode fingers connected to the bus bar electrode 141a are continuously arranged between the two electrode fingers 142b constituting the IDT electrode 140b.

The number of the extraction electrodes 143 is not limited to one, but may be two or more. At this time, two or more consecutive electrode fingers 142b connected to the bus bar electrode 141b may be used as the lead-out electrodes 143, or two or more non-continuous electrode fingers 142b may be used as the lead- do.

For example, when two consecutive lead electrodes 143a and 143b are formed, as shown in Fig. 6A, between two electrode fingers 142b constituting the IDT electrode 140b, The electrode fingers 142a and the extraction electrodes 143a and 143b connected to the first electrode 141a are arranged in succession. 6B, between the two electrode fingers 142b constituting the IDT electrode 140b, the bus bar electrode 142a is formed between the two electrode fingers 142b. In the case of forming the three consecutive lead electrodes 143a, 143b and 143c, Seven electrode fingers 142a and lead electrodes 143a, 143b, and 143c connected to the electrode 141a are arranged in series. The noise figure and the gain of the surface acoustic wave filter 10a and the low noise amplifier 20 can be matched by changing the number of the extraction electrodes 143 as will be described in detail later. That is, the number of lead-out electrodes is an electrode parameter for matching the noise figure and the gain of the surface acoustic wave filter 10a and the low noise amplifier 20.

The lead electrode 143 may be connected to the bus bar electrode 141a connected to the ground or to the bus bar electrode 141b connected to the output terminal 12 as described above.

7 is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10a according to the present embodiment. 7 shows the reflection characteristics on the output terminal side of the surface acoustic wave filter 10a when the lead electrodes 143 are formed successively with 0, 1, 2, and 3, respectively, as solid lines, broken lines, Indicated by two-dot chain lines.

When the number of the extraction electrodes 143 is increased to 0, 1, 2, or 3, the output impedance shifts to the capacitive side on the Smith chart as shown in FIG. Therefore, when the output impedance of the surface acoustic wave filter 10a is to be changed to the capacitive side, it is understood that the use of the extraction electrode 143 is effective. In addition, by increasing the number of consecutive outgoing electrodes 143, the output impedance can be changed to a more capacitive side.

Here, the position where the lead electrode 143 is formed in the resonator 14a will be described. 8 is a schematic diagram showing the configuration of the resonator 14a for explaining the position where the lead electrode 143a is formed in the surface acoustic wave filter 10a according to the present embodiment. 9 is a diagram showing the relationship between the position where the lead electrode 143 is formed and the signal loss on the output terminal side of the surface acoustic wave filter 10a in the surface acoustic wave filter 10a according to the present embodiment. The vertical axis of Fig. 9 indicates that the signal loss increases toward the bottom of the paper, and the signal loss decreases toward the top of the paper.

As shown in Fig. 8, the lead-out electrode 143 is formed at the central portion with respect to the whole of the resonator 14a. The region where the drawing electrode 143 is formed is called a drawing region.

In the resonator 14a, narrow pitch regions are formed in the vicinities of both ends in the propagation direction of the surface acoustic waves, as described above. Here, it is assumed that changing the arrangement of the electrode fingers 142a and 142b in the narrow pitch region when the position at which the lead electrode 143 is formed in the resonator 14a is changed, do.

For example, in the case where the lead electrode 143 is formed in a predetermined range at both ends of the resonator 14a in order to match the impedance on the output terminal side of the surface acoustic wave filter 10a, It can be seen that the signal loss (mismatch loss) due to the mismatch of the impedance on the output terminal side of the surface acoustic wave filter 10a deteriorates, that is, it is large and the impedance on the output terminal side is not matched. On the other hand, when the lead electrode 143a is formed in the central portion of the resonator 14a, it can be seen that the mismatch loss is small (for example, about 5 dB) and the impedance on the output terminal side is matched . When the lead electrode 143 is not formed, the mismatch loss is about 5.5 dB. When the lead electrode 143 is formed at the center of the resonator 14a, that is, when the lead- It can be understood that the mismatch loss does not deteriorate in the same manner as in the case where the drawing electrode 143a is not formed. More specifically, in Fig. 9, the lead-out region for preventing the mismatch loss from deteriorating is about 46% of the center portion with respect to the entire resonator 14a.

From the above, the lead electrode 143 is preferably formed at the central portion of the resonator 14a. For example, the drawing electrode 143 may be formed in a range of 46% of the center portion of the resonator 14a.

[3. Adjustment of output impedance of surface acoustic wave filter]

Next, adjustment of the output impedance of the surface acoustic wave filter 10a when the low noise amplifier 20 is connected to the surface acoustic wave filter 10a will be described.

10 is a diagram for explaining a method of adjusting the output impedance of the surface acoustic wave filter 10a according to the present embodiment.

Since the surface acoustic wave filter 10a is connected to the low noise amplifier 20 and used as the high frequency module 1 as shown in FIG. 1, it is necessary to adjust the output impedance so that the transmission characteristics of the entire high frequency module 1 are improved. . That is, the output impedance of the surface acoustic wave filter 10a is adjusted in accordance with the input impedance of the low-noise amplifier 20.

More specifically, at the position of the complex conjugate of the input impedance of the low noise amplifier 20 when the low noise amplifier 20 is viewed from the surface acoustic wave filter 10a side in the Smith chart, the output impedance of the surface acoustic wave filter 10a The output impedance of the surface acoustic wave filter 10a is adjusted. Here, the input impedance of the low-noise amplifier 20 is an input impedance that satisfies the improvement in characteristics of both the gain of the low-noise amplifier 20 and the noise figure. That is, in the Smith chart, the difference between the input impedance of the low-noise amplifier 20 at which the gain of the low-noise amplifier 20 becomes maximum and the input impedance of the low-noise amplifier 20 at which the noise figure of the low- Is the input impedance located in the region. The output impedance of the surface acoustic wave filter 10a is adjusted to the complex conjugate region (the target Imp region of the SAW output stage shown in Fig. 10) corresponding to this region.

10, when the output impedance of the surface acoustic wave filter 10a in the pass band is larger than that of the surface acoustic wave filter 10a when the gain of the low noise amplifier 20 is maximized, Between the output impedance (first output impedance) of the SAW output terminal and the output impedance (second output impedance) of the surface acoustic wave filter 10a when the noise figure of the low noise amplifier 20 becomes the minimum The output impedance of the surface acoustic wave filter 10a is adjusted.

At this time, the output impedance of the surface acoustic wave filter 10a is adjusted by forming the lead electrode 143 described above. The output impedance of the surface acoustic wave filter 10a is adjusted by increasing or decreasing the number of the extraction electrodes 143. [ That is, the number of the extraction electrodes 143 is set as an electrode parameter for adjusting the output impedance of the surface acoustic wave filter 10a to be present in the target Imp region of the SAW output stage. In order to adjust the output impedance of the surface acoustic wave filter 10a, the electrode finger 142b of the IDT electrode 140b on the output terminal 12 side of the surface acoustic wave filter 10a is connected to the bus bar electrode 141a To be the lead electrode 143. Thus, since the electrode fingers of the same polarity are arranged in only a part of the resonator 14a, the capacitance of the resonator 14a is smaller than that of the case where the lead electrode 143 is not formed. As a result, the impedance on the output terminal side of the surface acoustic wave filter 10a to which the resonator 14a having the lead electrode 143 is connected is changed. 7, since the impedance on the output terminal side of the surface acoustic wave filter 10a changes to the capacitive side by forming the extraction electrode 143, the impedance of the SAW output terminal on the Smith chart The impedance on the output terminal side of the surface acoustic wave filter 10a can be easily adjusted so as to exist in the Imp region.

11A is a diagram showing the pass characteristic of the surface acoustic wave filter 10a when the output impedance of the surface acoustic wave filter 10a according to the present embodiment is adjusted. 11B is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10a when the output impedance of the surface acoustic wave filter 10a according to the present embodiment is adjusted. 11C is a diagram showing the pass characteristic of the high frequency module 1 when the output impedance of the surface acoustic wave filter 10a according to the present embodiment is adjusted. 11A to 11C, the characteristics in the case where the drawing electrode 143a is not formed and the characteristics in the case where the drawing line and the drawing electrode 143 are formed are indicated by broken lines.

As shown in Fig. 11A, when the output impedance of the surface acoustic wave filter 10a is adjusted, in comparison with the case where the output impedance of the surface acoustic wave filter 10a is not adjusted, . The output impedance in the pass band of the surface acoustic wave filter 10a at this time is adjusted so as to exist in the target Imp region of the above SAW output stage, as shown in Fig. 11B.

On the other hand, as to the passing characteristics of the entire high-frequency module 1 including the low-noise amplifier 20 in the surface acoustic wave filter 10a, the insertion loss is improved in the pass band as shown in Fig. 11C . Therefore, in the surface acoustic wave filter 10a, the lead electrode 143 is formed on the resonator 14a on the output terminal side, and the SAW filter is formed so as to be in the target Imp region of the SAW output terminal on the Smith chart The transmission characteristics of the entire high-frequency module 1 including the low-noise amplifier 20 can be improved in the surface acoustic wave filter 10a by adjusting the output impedance of the SAW filter 10a.

[4. Effect, etc.]

As described above, according to the high frequency module of the present embodiment, in the surface acoustic wave filter 10a, the lead electrode 143 is formed on the resonator 14a on the output terminal side, and the SAW output terminal The transmission characteristics of the entire high-frequency module 1 including the low-noise amplifier 20 can be improved in the surface acoustic wave filter 10a by adjusting the output impedance of the surface acoustic wave filter 10a so as to exist in the target Imp region.

At this time, the output impedance of the surface acoustic wave filter 10a can be changed to a more capacitive state by increasing the number of the consecutive outgoing electrodes 143 formed.

(Embodiment 2)

Next, a second embodiment will be described with reference to Figs. 12A to 14B. The high frequency module according to the present embodiment is different from the high frequency module 1 according to the first embodiment in that the IDT electrode of the resonator 14b on the output terminal side , And is divided into two in the cross width direction.

First, the configuration of the surface acoustic wave filter 10b according to the present embodiment will be described.

12A is a schematic diagram showing a configuration of a surface acoustic wave filter 10b according to the present embodiment. 12B is a schematic view showing the configuration of the resonator 14b in the surface acoustic wave filter 10b according to the present embodiment.

As shown in Fig. 12A, the surface acoustic wave filter 10b has a resonator 13, a resonator 14b, and a resonator 15. As shown in Fig. The configurations of the resonator 13 and the resonator 15 are the same as those of the resonator 13 and the resonator 15 shown in the first embodiment, and a description thereof will be omitted.

As shown in Fig. 12A, the resonator 14b has IDT electrodes divided into two in the cross-width direction. That is, the resonator 14b has the first IDT electrode 145a and the second IDT electrode 145b connected in series in the cross-width direction, as shown in Fig. 12B. That is, in the surface acoustic wave filter 10b, the number of divisions of the IDT electrodes is two.

More specifically, as shown in Fig. 12B, the resonator 14b has a structure in which the IDT electrode 140a, the IDT electrode 140b, and the IDT electrode 140c are combined. Like the IDT electrode 140a shown in the first embodiment, the IDT electrode 140a has a bus bar electrode 141a and a plurality of electrode fingers 142a one end of which is connected to the bus bar electrode 141a. Similarly, the IDT electrode 140b has a bus bar electrode 141b and a plurality of electrode fingers 142b connected at one end to the bus bar electrode 141b. The IDT electrode 140c includes a bus bar electrode 141c and an electrode finger 142c connected at one end to the bus bar electrode 141c and provided from the bus bar electrode 141c toward the bus bar electrode 141a, And an electrode finger 142d having one end connected to the bar electrode 141c and provided from the bus bar electrode 141c toward the bus bar electrode 141b. The electrode fingers 142a and the electrode fingers 142c are alternately arranged in the propagation direction of the surface acoustic waves. Similarly, the electrode fingers 142b and the electrode fingers 142d are alternately arranged in the propagation direction of the surface acoustic waves.

The first IDT electrode 145a includes the IDT electrode 140a and the bus bar electrode 141c and the electrode finger 142c of the IDT electrode 140c. The second IDT electrode 145b includes the IDT electrode 140b and the bus bar electrode 141c and the electrode finger 142d of the IDT electrode 140c. The bus bar electrode 141c is commonly used for the first IDT electrode 145a and the second IDT electrode 145b.

The distance between the bus bar electrode 141a and the bus bar electrode 141b in the resonator 14b is larger than the distance between the bus bar electrode 141b in the resonator 14 in which the IDT electrode is not divided in the cross width direction 141a and the bus bar electrode 141b. That is, the length of the first IDT electrode 145a and the second IDT electrode 145b in the cross-width direction is shorter than the length of the IDT electrode in the cross-width direction of the resonator 14 not divided in the cross-width direction have. For example, the lengths of the first IDT electrode 145a and the second IDT electrode 145b in the cross-width direction are respectively equal to the lengths of the first IDT electrode 145a and the second IDT electrode 145b in the cross-width direction when the IDT electrodes are not divided in the cross- 2 < / RTI >

With this configuration, the output impedance of the surface acoustic wave filter 10b can be increased as shown below.

Here, transmission characteristics of the surface acoustic wave filter 10b and the high frequency module 1 when the output impedance of the surface acoustic wave filter 10b is adjusted by the resonator 14b described above will be described.

13 is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10b according to the present embodiment. 14A is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter 10b according to the present embodiment. 14B is a diagram showing the noise characteristic on the output terminal side of the entire high-frequency module 1 having the surface acoustic wave filter 10b according to the present embodiment. 13 shows the characteristics of the surface acoustic wave filter 10 using the resonator 14 in which the IDT electrode is not divided in the cross width direction by the solid line and the elasticity using the resonator 14b obtained by dividing the IDT electrode in the cross width direction The characteristic of the surface acoustic wave filter 10b is indicated by a one-dot chain line. 14A and 14B show the characteristics of the surface acoustic wave filter 10 using the resonator 14 in which the IDT electrode is not divided in the cross width direction by the solid line and the resonator 14b obtained by dividing the IDT electrode in the cross width direction. The characteristic of the surface acoustic wave filter 10b using the filter shown in Fig.

As described above, the output impedance of the surface acoustic wave filter 10b using the resonator 14b obtained by dividing the IDT electrode in the cross width direction is obtained by dividing the IDT electrode in the cross width direction The output impedance of the surface acoustic wave filter 10 using the non-resonator 14 is shifted in the direction of increasing the output impedance in the pass band on the Smith chart.

This is because the first IDT electrode 145a and the second IDT electrode 145b, which are about half the length in the cross-width direction, are connected in series in the cross-width direction by dividing the IDT electrode into two, Is about four times. Therefore, as shown in Fig. 13, the output impedance of the surface acoustic wave filter 10b is increased.

14A, when the output impedance of the surface acoustic wave filter 10b is adjusted, in comparison with the case where the output impedance of the surface acoustic wave filter 10b is not adjusted in the SAW filter 10b alone, The loss is large. The output impedance in the pass band of the surface acoustic wave filter 10b at this time is adjusted so as to exist in the target Imp region of the SAW output terminal shown in Fig. 11B in the first embodiment.

On the other hand, with respect to the entire high-frequency module 1 including the low noise amplifier 20 in the surface acoustic wave filter 10b, if the surface acoustic wave filter 10b in which the IDT electrode is divided into two parts as shown in Fig. 14B is used, It can be seen that the noise figure is reduced in the pass band of the high-frequency module 1 as compared with the case where the electrode is not divided into two. This is because the surface acoustic wave filter 10b is constituted by the resonator 14b obtained by dividing the IDT electrode so that the output impedance of the surface acoustic wave filter 10b is close to the NF circle of the low noise amplifier 20 on the Smith chart It is considered that the noise characteristic of the entire high-frequency module 1 is improved.

Therefore, in the surface acoustic wave filter 10b, the IDT electrode of the resonator 14b on the output terminal side is divided, and the surface acoustic wave filter 10b is arranged so as to exist in the target Imp region of the SAW output terminal on the Smith chart. The transmission characteristics of the entire high-frequency module 1 including the low-noise amplifier 20 can be improved in the surface acoustic wave filter 10b by adjusting the output impedance of the SAW filter 10b.

In the above-described surface acoustic wave filter 10b, only the resonator 14b obtained by dividing the IDT electrode of the resonator 14 into two is described. However, the number of divisions of the IDT electrode of the resonator 14b is two But may be three or more.

In the above-described surface acoustic wave filter 10b, the IDT electrode is divided with respect to the resonator 14b connected to the output terminal of the surface acoustic wave filter 10b in order to adjust the output impedance of the surface acoustic wave filter 10b However, in the case of adjusting the input impedance of the surface acoustic wave filter 10b, the IDT electrode of the resonator connected to the input terminal of the surface acoustic wave filter 10 may be divided.

(Embodiment 3)

Next, a third embodiment will be described with reference to Figs. 15 to 18B. The high frequency module according to the present embodiment is different from the high frequency module 1 according to the first embodiment in that the output impedance of the surface acoustic wave filter 10c is adjusted by connecting The main wavelength in the resonator and the main wavelength in the resonator connected to the output terminal side are adjusted.

First, a description will be given of a longitudinally coupled surface acoustic wave filter 10c having three resonators as an example of the configuration of the surface acoustic wave filter according to the present embodiment.

15 is a schematic diagram showing the configuration of a surface acoustic wave filter 10c according to the present embodiment. As shown in Fig. 15, the surface acoustic wave filter 10c is a longitudinally coupled surface acoustic wave filter. The surface acoustic wave filter 10c includes a resonator 13, a resonator 14c and a resonator 15 and a reflector 16 and a reflector 17 between the input terminal 11 and the output terminal 12. [ . The resonator 13, the resonator 14c and the resonator 15 are arranged in this order from the reflector 16 side to the reflector 17 side.

The resonator 13 and the resonator 15 are connected to the input terminal 11 of the surface acoustic wave filter 10c. The resonator 14c is connected to the output terminal 12 of the surface acoustic wave filter 10c. The input impedance of the input terminal 11 and the output impedance of the output terminal 12 of the surface acoustic wave filter 10c are respectively 50?.

The configurations of the resonator 13 and the resonator 15 are the same as those of the surface acoustic wave filter 10 shown in the first embodiment. The configurations of the reflector 16 and the reflector 17 are the same as those of the surface acoustic wave filter 10 shown in the first embodiment.

The resonator 14c has a structure in which two IDT electrodes 140a and 140b are combined as in the resonator 14 shown in the first embodiment. The IDT electrode 140a has a bus bar electrode 141a and a plurality of electrode fingers 142a one end of which is connected to the bus bar electrode 141a. Similarly, the IDT electrode 140b has a bus bar electrode 141b and a plurality of electrode fingers 142b connected at one end to the bus bar electrode 141b.

The resonator 13 and the resonator 15 connected to the input terminal 11 of the surface acoustic wave filter 10c and the resonator 14c connected to the output terminal 12 of the surface acoustic wave filter 10c are connected, The average value of the main wavelengths is different. Since the resonator 14c connected to the output terminal 12 has only one resonator connected to the output terminal 12, the main wavelength itself of the resonator 14c is an average value of the main wavelength. The main wavelengths of the resonator 13 and the resonator 15 may be the same or different.

For example, the main wavelengths of the resonator 13 and the resonator 15 are 4.515 mu m and 4.525 mu m, respectively, and the mean value of the main wavelengths may be 4.520 mu m.

The main wavelength of the resonator 14c may be 4.542 mu m. The resonator 14c connected to the output terminal 12 of the surface acoustic wave filter 10c has an average value of the main wavelengths of the resonator 14c connected to the input terminal 11 of the surface acoustic wave filter 10c. (Main wave equipment) with respect to the average value of the main wavelengths in the optical waveguides 13 and 15 is 1.005.

The average value of the main wavelengths of the resonator 13 and the resonator 15 connected to the input terminal 11 of the surface acoustic wave filter 10c corresponds to the first main wavelength in the present invention. The average value of the main wavelength of the resonator 14c connected to the output terminal 12 of the surface acoustic wave filter 10c corresponds to the second main wavelength in the present invention.

As described above, the average value (the first main wavelength) of the main wavelengths of the resonator 13 and the resonator 15 connected to the input terminal 11 of the surface acoustic wave filter 10c, (Main wave equipment) of the average value (second main wavelength) of the main wavelength of the resonator 14c connected to the output terminal 12 is changed so that the output of the surface acoustic wave filter 10c Impedance can be adjusted.

Hereinafter, the transmission characteristics of the surface acoustic wave filter 10c when the output impedance of the surface acoustic wave filter 10c is adjusted by changing the main wave equipment as described above will be described. 16A and 16B, transmission characteristics of the surface acoustic wave filter 10c when the main wave equipment is set to 1.005, 1.008, and 1.012 in the surface acoustic wave filter 10c will be described.

16A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10c according to the present embodiment. Fig. 16B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter 10c according to the present embodiment. 16A and 16B, the characteristics of the surface acoustic wave filter 10c when the main wave equipment is set to 1.005, 1.008, and 1.012 are indicated by solid lines, one-dot chain lines, and dashed lines, respectively.

The output impedance in the pass band of the surface acoustic wave filter 10c when the main wave equipment is set to 1.005, 1.008, and 1.012 is set to the right side in the Smith chart as the main wavelength ratio increases as shown in Fig. 16A Moving. That is, as the main wave equipment is increased, the output impedance of the surface acoustic wave filter 10c increases.

Therefore, by increasing the main wave equipment of the resonators 13, 14c, and 15 in the surface acoustic wave filter 10c, the output impedance of the surface acoustic wave filter 10c can be increased to 50?.

1, the output impedance of the surface acoustic wave filter 10c is preferably set to about 70 OMEGA. When the low-noise amplifier 20 is provided at the rear end of the surface acoustic wave filter 10c, Do. In order to increase the output impedance of the surface acoustic wave filter 10c to about 70 ?, the main wave equipment is preferably 1.01 or more.

16B, when the main wave equipment is set to 1.005, 1.008, and 1.012, the pass band width of the surface acoustic wave filter 10c is enlarged. That is, it can be seen that as the main wave equipment is increased, the pass band of the surface acoustic wave filter 10c is enlarged.

17 is a schematic view showing the configuration of a longitudinally coupled surface acoustic wave filter 10d having five resonators as another configuration of the surface acoustic wave filter according to the present embodiment.

17, the surface acoustic wave filter 10d includes a resonator 23a, a resonator 24a, a resonator 25a, and a resonator 25b between the input terminal 11 and the output terminal 12, A resonator 27a, a reflector 16, and a reflector 17, as shown in Fig. The resonator 23a, the resonator 24a, the resonator 25a, the resonator 26a and the resonator 27a are arranged in this order from the reflector 16 side to the reflector 17 side.

The resonator 23a, the resonator 25a and the resonator 27a are connected to the input terminal 11 of the surface acoustic wave filter 10d. The resonator 24a and the resonator 26a are connected to the output terminal 12 of the surface acoustic wave filter 10d. The input impedance of the input terminal 11 and the output impedance of the output terminal 12 of the surface acoustic wave filter 10d are respectively 50?.

The configurations of the resonator 23a, the resonator 25a and the resonator 27a are the same as those of the resonator 13 of the surface acoustic wave filter 10c described above. The configurations of the resonator 24a and the resonator 26a are the same as those of the resonator 14 of the surface acoustic wave filter 10c described above.

A resonator 23a, a resonator 25a and a resonator 27a connected to the input terminal 11 of the surface acoustic wave filter 10d and a resonator 23a connected to the output terminal 12 of the surface acoustic wave filter 10d. The resonator 24a and the resonator 26a have different average values of the main wavelengths. The main wavelengths of the resonator 23a, the resonator 25a, and the resonator 27a may be the same or different. The main wavelengths of the resonator 24a and the resonator 26a may be the same or different.

The average value of the main wavelengths of the resonator 23a, the resonator 25a and the resonator 27a connected to the input terminal 11 of the surface acoustic wave filter 10d is the same as the average value of the first main wavelength . The average value of the main wavelengths of the resonator 24a and the resonator 26a connected to the output terminal 12 of the surface acoustic wave filter 10d corresponds to the second main wavelength in the present invention.

(First main wavelength) of the main wavelength of the resonator 23a, the resonator 25a and the resonator 27a connected to the input terminal 11 of the surface acoustic wave filter 10d, (Main wave equipment) of the average value (second main wavelength) of the main wavelength of the resonator 24a and the resonator 26a connected to the output terminal 12 of the resonator 26a Likewise, the output impedance of the surface acoustic wave filter 10d can be adjusted.

Hereinafter, the transmission characteristics of the surface acoustic wave filter 10d when the output impedance of the surface acoustic wave filter 10d is adjusted by changing the main wave equipment as described above will be described. 18A and 18B, transmission characteristics of the surface acoustic wave filter 10d when the main wave equipment is set to 1.005, 1.008, and 1.012 in the surface acoustic wave filter 10d will be described.

18A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10d according to the present embodiment. 18B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter 10d according to the present embodiment. 18A and 18B, the characteristics of the surface acoustic wave filter 10d when the main wave equipment is 1.005, 1.008, and 1.012 are shown by solid lines, one-dot chain lines, and dashed lines, respectively.

18A, the output impedance in the pass band of the surface acoustic wave filter 10d when the main wave equipment is set to 1.005, 1.008, and 1.012 is, similarly to the case of the surface acoustic wave filter 10c described above, As the main wavelength ratio increases, it moves in the right direction in the Smith chart. That is, as the main wave equipment is increased, the output impedance of the surface acoustic wave filter 10d increases.

Therefore, by increasing the main wave equipment of the resonator 23a, the resonator 24a, the resonator 25a, the resonator 26a and the resonator 27a in the surface acoustic wave filter 10d, The output impedance of the filter 10d can be increased to 50?.

18A and 16A, the output impedance of the surface acoustic wave filter 10d having five resonators is compared with the output impedance of the surface acoustic wave filter 10c having three resonators, and the output impedance of the surface acoustic wave filter 10d The curl of the output impedance in the pass band of the resonator is small. That is, by increasing the number of resonators like the surface acoustic wave filter 10d, the output impedance of the surface acoustic wave filter 10d can be increased and stabilized.

Also, in the surface acoustic wave filter 10d, it is preferable that the main wave equipment is 1.01 or more in order to increase the output impedance to about 70 ?.

18B, when the main wave equipment is set to 1.005, 1.008, and 1.012, the pass band width of the surface acoustic wave filter 10d is enlarged similarly to the above-described surface acoustic wave filter 10c. That is, it can be seen that as the main wave equipment is increased, the pass band of the surface acoustic wave filter 10d is enlarged.

Although the SAW filter 10c having three resonators and the SAW filter 10d having five resonators have been described in the present embodiment, the number of resonators is not limited to these, and may be changed .

(Fourth Embodiment)

Next, Embodiment 4 will be described with reference to Figs. 19 to 22B. The high frequency module according to the present embodiment differs from the high frequency module 1 according to the first embodiment in that the output impedance of the surface acoustic wave filter 10 is adjusted by changing the impedance of the output terminal connected to the output terminal side of the surface acoustic wave filter 10 And the main duty in the resonator is adjusted.

First, as an example of the configuration of the surface acoustic wave filter according to the present embodiment, a longitudinally coupled surface acoustic wave filter 10e having three resonators will be described.

19 is a schematic diagram showing the configuration of a surface acoustic wave filter 10e according to the present embodiment.

As shown in Fig. 19, the surface acoustic wave filter 10e is a longitudinally coupled surface acoustic wave filter. The surface acoustic wave filter 10e includes a resonator 13, a resonator 14d and a resonator 14b between the input terminal 11 and the output terminal 12, like the surface acoustic wave filter 10c shown in the third embodiment. (15), a reflector (16), and a reflector (17). The resonator 13, the resonator 14d and the resonator 15 are arranged in this order from the reflector 16 side to the reflector 17 side.

The resonator 13 and the resonator 15 are connected to the input terminal 11 of the surface acoustic wave filter 10e. The resonator 14d is connected to the output terminal 12 of the surface acoustic wave filter 10e. The configurations of the resonator 13 and the resonator 15 are the same as those of the surface acoustic wave filter 10 shown in the first embodiment. The resonator 14d is the same as the resonator 14 shown in the first embodiment except for the main duty.

The main duty of the resonator 14d is, for example, 0.64. The output impedance of the surface acoustic wave filter 10e can be adjusted by changing the main duty of the resonator 14d connected to the output terminal 12 of the surface acoustic wave filter 10e.

Hereinafter, the transmission characteristics of the surface acoustic wave filter 10e when the output impedance of the surface acoustic wave filter 10e is adjusted by changing the main duty as described above will be described. 20A and 20B, transmission characteristics of the surface acoustic wave filter 10e when the main duty of the surface acoustic wave filter 10e is set to 0.64, 0.71, and 0.75 will be described.

20A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10e according to the present embodiment. 20B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter 10e according to the present embodiment. 20A and 20B show the characteristics of the surface acoustic wave filter 10e when the main duty of the resonator 14d is 0.64, 0.71, and 0.75, respectively, by the one-dot chain line, the solid line, and the broken line.

The output impedance of the surface acoustic wave filter 10e in the pass band when the main duty of the resonator 14d is set to 0.64, 0.71, and 0.75 becomes larger as the main duty increases, As shown in Fig. That is, as the main duty increases, the output impedance of the surface acoustic wave filter 10e decreases.

Therefore, by reducing the main duty of the resonator 14d in the surface acoustic wave filter 10e, the output impedance of the surface acoustic wave filter 10e can be increased to 50?.

1, the output impedance of the surface acoustic wave filter 10e is preferably set to about 70? When the low-noise amplifier 20 is provided at the rear end of the surface acoustic wave filter 10e Do. In order to increase the output impedance of the surface acoustic wave filter 10e to about 70 ?, the main duty of the resonator 14d is preferably larger than 0.55 and smaller than 0.75. When the output impedance of the surface acoustic wave filter 10e is 50?, The main duty of the resonator 14d is, for example, larger than 0.4 and smaller than 0.6.

20B, even when the main duty is changed to 0.64, 0.71, and 0.75, the pass band width of the surface acoustic wave filter 10e hardly changes. That is, by changing the main duty, the output impedance of the surface acoustic wave filter 10e can be changed without changing the pass band of the surface acoustic wave filter 10e.

21 is a schematic diagram showing the configuration of a longitudinally coupled surface acoustic wave filter 10f having five resonators as another configuration of the surface acoustic wave filter according to the present embodiment.

21, the surface acoustic wave filter 10f includes a resonator 23b, a resonator 24b, a resonator 25b, and a resonator 25b between the input terminal 11 and the output terminal 12, A resonator 26b and a resonator 27b, and a reflector 16 and a reflector 17 as shown in Fig. The resonator 23b, the resonator 24b, the resonator 25b, the resonator 26b and the resonator 27b are arranged in this order from the reflector 16 side to the reflector 17 side.

The resonator 24b and the resonator 26b are connected to the input terminal 11 of the surface acoustic wave filter 10f. The resonator 23b, the resonator 25b and the resonator 27b are connected to the output terminal 12 of the surface acoustic wave filter 10f. The input impedance of the input terminal 11 and the output impedance of the output terminal 12 of the surface acoustic wave filter 10f are respectively 50?.

The configurations of the resonator 24b and the resonator 26b are the same as those of the resonator 13 of the surface acoustic wave filter 10e. The configurations of the resonator 23b, the resonator 25b and the resonator 27b are the same as those of the resonator 14d of the surface acoustic wave filter 10e.

Here, the transmission characteristics of the surface acoustic wave filter 10f when the output impedance of the surface acoustic wave filter 10f is adjusted by changing the main duty as described above will be described. 22A and 22B, transmission characteristics of the surface acoustic wave filter 10f when the main duty is small, medium, and large in the surface acoustic wave filter 10f will be described. The main duty of the resonators 23b and 27b is 0.64 and the main duty of the resonator 25b is 0.67 when the main duty of the surface acoustic wave filter 10f is small. When the main duty of the surface acoustic wave filter 10f is high, the main duty of the resonators 23b and 27b is 0.70 and the main duty of the resonator 25b is 0.74. When the main duty of the surface acoustic wave filter 10f is large, the main duty of the resonators 23b and 27b is 0.74 and the main duty of the resonator 25b is 0.77.

22A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10f according to the present embodiment. Fig. 22B is a diagram showing the transmission characteristics on the output terminal side of the surface acoustic wave filter 10f according to the present embodiment. In Figs. 22A and 22B, the characteristics of the surface acoustic wave filter 10f when the main duty is the above-described small, medium, and the same are indicated by solid lines, one-dot chain lines and dashed lines, respectively.

The output impedance in the pass band of the surface acoustic wave filter 10f when the main duty of the resonators 23b, 25b, and 27b connected to the output terminal 12 is small, medium, As shown in Fig. 22A, the filter 10e moves in the left direction in the Smith chart as the main duty of the resonators 23b, 25b, and 27b increases. That is, as the main duty of the resonators 23b, 25b, and 27b increases, the output impedance of the surface acoustic wave filter 10f decreases.

Therefore, by reducing the main duty of the resonators 23b, 25b, and 27b in the surface acoustic wave filter 10f, the output impedance of the surface acoustic wave filter 10f can be increased to 50Ω or more.

1, the output impedance of the surface acoustic wave filter 10f is preferably set to about 70? When the low-noise amplifier 20 is provided at the rear end of the surface acoustic wave filter 10f Do. In order to increase the output impedance of the surface acoustic wave filter 10f to about 70Ω, the main duty of each of the resonators 23b, 25b, and 27b is preferably larger than 0.55 and smaller than 0.75.

22B, even if the main duty of the resonators 23b, 25b, and 27b is changed in accordance with the above-described small or medium, the pass band width of the surface acoustic wave filter 10f hardly changes. That is, by changing the main duty of the resonators 23b, 25b, and 27b, the output impedance of the surface acoustic wave filter 10f can be changed without changing the pass band of the surface acoustic wave filter 10f.

Further, the value of the main duty is not limited to the above-described value, and may be appropriately changed.

(Embodiment 5)

Next, Embodiment 5 will be described with reference to Figs. 23 to 25B. The high-frequency module according to the present embodiment is different from the high-frequency module 1 according to the first embodiment in that in the surface acoustic wave filter 10g, with respect to the wiring between the resonator and the output terminal connected to the output terminal, And an interlayer insulating film 40 is disposed between the substrate and the substrate.

23 is a schematic diagram showing the configuration of a surface acoustic wave filter 10g according to the present embodiment. As shown in Fig. 23, the surface acoustic wave filter 10g according to the present embodiment has a configuration in which two longitudinally coupled surface acoustic wave resonators 10ga and 10gb are connected in series.

The first surface acoustic wave resonator 10ga includes a resonator 33a, a resonator 34a and a resonator 35a and a reflector 36a and a reflector 37a as shown in Fig. 23 . The resonator 33a, the resonator 34a and the resonator 35a are arranged in this order from the reflector 36a side to the reflector 37a side. The configurations of the resonator 33a, the resonator 34a and the resonator 35a and the reflector 36a and the reflector 37a are the same as those of the resonator 13 of the surface acoustic wave filter 10 of the first embodiment, The configuration of the resonator 14 and the resonator 15, and the configurations of the reflector 16 and the reflector 17 are the same.

23, the second surface acoustic wave resonator 10gb includes a resonator 33b, a resonator 34b and a resonator 35b, a reflector 36b and a reflector 37b . The resonator 33b, the resonator 34b and the resonator 35b are arranged in this order from the reflector 36b side to the reflector 37b side. The configurations of the resonator 33b, the resonator 34b and the resonator 35b and the configurations of the reflectors 36b and 37b are the same as those of the resonator 13, The configuration of the resonator 14 and the resonator 15, and the configurations of the reflector 16 and the reflector 17 are the same.

In the resonator 34a, one of the pair of IDT electrodes is connected to the input terminal 11 of the surface acoustic wave filter 10g. In the resonator 34b, one of the pair of IDT electrodes is connected to the output terminal 12 of the surface acoustic wave filter 10g. The other one of the pair of IDT electrodes of the resonator 34a and the other of the pair of IDT electrodes of the resonator 34b are connected to the ground.

In the resonator 33a, one of the pair of IDT electrodes is connected to one of the pair of IDT electrodes of the resonator 33b. The other one of the pair of IDT electrodes of the resonator 33a and the other of the pair of IDT electrodes of the resonator 33b are connected to the ground.

Similarly, in the resonator 35a, one of the pair of IDT electrodes is connected to one of the pair of IDT electrodes of the resonator 35b. The other one of the pair of IDT electrodes of the resonator 35a and the other of the pair of IDT electrodes of the resonator 35b are connected to the ground.

With this configuration, the surface acoustic wave filter 10g is configured such that the longitudinally coupled first surface acoustic wave resonator 10ga and the second surface acoustic wave resonator 10gb are connected directly between the input terminal 11 and the output terminal 12 Respectively. Thus, in the case where the surface acoustic wave filter 10g includes a plurality of stages of surface acoustic wave resonators, in order to ensure grounding of each surface acoustic wave resonator, interconnection may be performed in three dimensions using an interlayer insulating film. That is, there is a case where an interlayer insulating film is formed on one lead interconnection and another lead interconnection is formed on the interlayer insulating film.

In the surface acoustic wave filter 10g according to the present embodiment, the IDT electrode of one of the resonators 34b and the output terminal 12 are connected not to a position where such a three-dimensional wiring is required but to a three- An interlayer insulating film 40 is formed between the wiring 39 and the piezoelectric substrate 42 at the position of the wiring 39. [

24A is a cross-sectional view showing the configuration of the surface acoustic wave filter 10g shown in FIG. 23 on the line B-B. 24B is a cross-sectional view showing the configuration on the line C-C of the surface acoustic wave filter 10g shown in Fig.

24A and 24B, the surface acoustic wave filter 10g is formed on the piezoelectric substrate 42 in the same manner as the surface acoustic wave filter 10 shown in the first embodiment. The wiring connected to the IDT electrode of the resonator has the same structure as that of the IDT electrode.

Specifically, as shown in Fig. 24A, the wiring 38 connecting one IDT electrode of the resonator 34b to the ground in Fig. 23 has a first electrode layer 38a formed on the piezoelectric substrate 42, And a second electrode layer 38b formed on the first electrode layer 38a.

The first electrode layer 38a is formed integrally with the main electrode layer of the IDT electrode and includes, for example, Pt, Cu, Au, Ag, Ta, W and the like. The first electrode layer 38a may be provided with an adhesive layer (see FIG. 3 (b)) on the piezoelectric substrate 42 side. The thickness of the first electrode layer 38a is a submicrometer order, for example, 0.2 占 퐉. The second electrode layer 38b includes, for example, Pt, Cu, Au, Ag, Ta, W, and the like. The thickness of the second electrode layer 38b is micrometer order, for example, 2 탆.

A protective layer 44 is formed to cover the second electrode layer 38b. The protective layer 44 includes, for example, SiO ₂ or the like. The thickness of the protective layer 44 is several tens nm, for example, 30 nm.

The wiring 39 connecting the other IDT electrode of the resonator 34b to the output terminal 12 in Fig. 23 is formed on the interlayer insulating film 40 (not shown) formed on the piezoelectric substrate 42, As shown in Fig. That is, in the wiring 39, an interlayer insulating film 40 is formed in place of the first electrode layer 38a, as compared with the wiring 38 described above.

The interlayer insulating film 40 includes, for example, polyimide and the like. The thickness of the interlayer insulating film is on the order of micrometers, and is, for example, 3 占 퐉. The wiring 39 includes the same material as the second electrode layer 38b shown in Fig. 24A. The wiring 39 includes, for example, Pt, Cu, Au, Ag, Ta, W and the like. 24B, a protective layer 44 is formed on the piezoelectric substrate 42 so as to cover the interlayer insulating film 40 and the wiring 39. As shown in Fig.

By forming the interlayer insulating film 40 between the wiring 39 connected to the output terminal 12 and the piezoelectric substrate 42 as compared with the configuration of the wiring 38 in which the interlayer insulating film 40 is not formed, The capacitive coupling between the substrate 42 and the wiring 39 can be reduced. Thereby, the output impedance of the surface acoustic wave filter 10g can be adjusted inductively.

Further, as shown in Fig. 24B, the capacitance coupling between the piezoelectric substrate 42 and the wiring 39 can be further reduced by making the area of the interlayer insulating film 40 larger than the area of the wiring 39. [ Thereby, the output impedance of the surface acoustic wave filter 10g can be adjusted more inductively.

The transmission characteristics of the surface acoustic wave filter 10g when the interlayer insulating film 40 is formed and when the interlayer insulating film 40 is not formed will be described below.

25A is a diagram showing the reflection characteristic on the output terminal side of the surface acoustic wave filter 10g of another structure according to the present embodiment. 25B is a diagram showing noise characteristics after the low noise amplifier 20 is connected to the surface acoustic wave filter 10g according to the present embodiment. 25A and 25B show characteristics of the surface acoustic wave filter 10g when the interlayer insulating film 40 is not formed between the wiring 39 connected to the output terminal 12 and the piezoelectric substrate 42, And the characteristics of the surface acoustic wave filter 10g in the case where the interlayer insulating film 40 is formed instead of the first electrode layer 38a are shown by broken lines.

The output impedance in the pass band of the surface acoustic wave filter 10g when the interlayer insulating film 40 is formed in place of the first electrode layer 38a forms the interlayer insulating film 40 as shown in Fig. The output impedance in the pass band of the surface acoustic wave filter 10g when it is not on the Smith chart is shifted to the upper right side, that is, the inductive side on the Smith chart. Therefore, by forming the interlayer insulating film 40, the capacitive coupling between the piezoelectric substrate 42 and the wiring 39 can be reduced.

In the high-frequency module 1 in which the low-noise amplifier 20 is connected to the output side of the surface acoustic wave filter 10g, an interlayer insulating film (not shown) is formed between the wiring 39 and the piezoelectric substrate 42 40 is formed, the noise figure is reduced as compared with the case where the interlayer insulating film 40 is not formed. Therefore, by forming the interlayer insulating film 40 between the wiring 39 and the piezoelectric substrate 42 in the surface acoustic wave filter 10g, it is possible to improve the noise characteristic in the entire high-frequency module 1. [

In the above-described surface acoustic wave filter 10g, the interconnection 39 connected to the output terminal 12 is formed with the interlayer insulating film 40 in place of the first electrode layer 38a, as compared with the interconnection 38 However, the wiring 39 may have both the first electrode layer and the second electrode layer.

26 is a cross-sectional view showing another configuration on the line C-C of the surface acoustic wave filter 10g shown in Fig. The wiring 39 shown in Fig. 26 has the first electrode layer 39a and the second electrode layer 39b similarly to the wiring 38 shown in Fig. 24A. The structures of the first electrode layer 39a and the second electrode layer 39b are the same as those of the first electrode layer 38a and the second electrode layer 38b. An interlayer insulating film 40 is formed between the wiring 39 and the piezoelectric substrate 42. A protective layer 44 is formed on the piezoelectric substrate 42 so as to cover the interlayer insulating film 40 and the wiring 39.

In the case where the interlayer insulating film 40 is formed between the wiring 39 and the piezoelectric substrate 42, the interlayer insulating film 40 is formed instead of the first electrode layer 39a, The change in the output impedance of the surface acoustic wave filter 10g becomes larger than that in forming the interlayer insulating film 40. [ Therefore, when it is desired to largely adjust the change of the output impedance of the surface acoustic wave filter 10g, the interlayer insulating film 40 is formed in place of the first electrode layer 39a and the change of the output impedance of the surface acoustic wave filter 10g It is preferable to form the interlayer insulating film 40 while leaving the first electrode layer 39a.

The surface acoustic wave filter 10g according to the present embodiment is configured to include the first surface acoustic wave resonator 10ga and the second surface acoustic wave resonator 10gb, May include a single stage longitudinally coupled surface acoustic wave resonator, or may include a multi-stage longitudinally coupled surface acoustic wave resonator.

(Other Embodiments)

The present invention is not limited to the configuration described in the above embodiment, and may be suitably modified, for example, as shown in the following modified examples.

For example, in the above-described embodiment, as the electrode parameters for adjusting the output impedance of the surface acoustic wave filter, the number of the extraction electrodes of the resonator connected to the output terminal, the number of division in the cross width direction of the resonator, Although the main duty has been described, other parameters may be used as electrode parameters. For example, the electrode finger pitch of the resonator, the number of electrode fingers, and the like may be used as electrode parameters. Further, the value of the electrode parameter is not limited to the value shown in the above-described embodiment, and may be appropriately changed.

The number of resonators constituting the surface acoustic wave filter is not limited to three or five, and may be changed.

The material of the substrate, the electrode, and the protective layer constituting the resonator is not limited to those described above, and may be appropriately changed. The size, pitch, and number of electrode fingers of each resonator may be changed as long as they satisfy the above-described conditions.

In the above-described embodiments, the surface acoustic wave filter and the low noise amplifier are directly connected. However, a matching element may be additionally provided between the surface acoustic wave filter and the low noise amplifier.

Further, according to the surface acoustic wave filter of this embodiment, since the output impedance of the surface acoustic wave filter can be adjusted, even when the surface acoustic wave filter and the low noise amplifier are directly connected as described above without providing a matching element, And low noise can be achieved.

It is to be understood that other embodiments and modifications may be made by those skilled in the art without departing from the spirit or scope of the present invention. Are also included in the present invention.

The present invention can be applied to a high-frequency module using a surface acoustic wave filter connected to a low-noise amplifier, a duplexer, a multiplexer, a receiver, and the like.

1: High frequency module
10, 10a, 10b, 10c, 10d, 10e, 10f, 10g:
10ga: first surface acoustic wave resonator
10 gb: second surface acoustic wave resonator
11: Input terminal
12: Output terminal
The resonator includes a resonator and a resonator. The resonator includes a first resonator, a second resonator, a second resonator, a second resonator, and a third resonator.
16, 17, 36a, 36b, 37a, 37b:
16a, 16b, 17a, 17b, 111a, 111b, 141a, 141b,
16c, 17c, 110a, 110b, 142a, 142b, 142c, 142d:
38, 39: wiring
38a, 39a: first electrode layer
38b, 39b: second electrode layer
40: Interlayer insulating film
42, 123: piezoelectric substrate
44, 125: protective layer
The IDT electrodes 101a, 101b, 130a, 130b, 140a, 140b, 140c, 150a,
143, 143a, 143b, 143c:
124a: Adhesive layer
124b: main electrode layer
145a: a first IDT electrode
145b: the second IDT electrode

Claims (12)

A longitudinally coupled surface acoustic wave filter having a plurality of resonators,
And a low noise amplifier connected to the surface acoustic wave filter for amplifying the high frequency signal passed through the surface acoustic wave filter,
The input impedance and the output impedance of the surface acoustic wave filter connected to the low noise amplifier are different from each other,
In the Smith chart, the output impedance in the pass band of the surface acoustic wave filter is determined by a first output impedance which is an output impedance of the surface acoustic wave filter when the gain of the low noise amplifier becomes the maximum, And a second output impedance which is an output impedance of the surface acoustic wave filter when the index becomes minimum,
High frequency module. The method according to claim 1,
Wherein the surface acoustic wave filter has an electrode parameter for adjusting the output impedance in the pass band of the surface acoustic wave filter to exist in the region in the Smith chart. 3. The method of claim 2,
(IDT) electrode of at least one of the resonators connected to the output terminal of the surface acoustic wave filter has an extraction electrode,
Wherein the electrode parameter is the number of the extraction electrodes,
High frequency module. The method of claim 3,
Wherein the lead electrode is formed in a central portion of the resonator,
High frequency module. 5. The method of claim 4,
Wherein the lead electrode is formed in a range of 46% of a central portion of the resonator,
High frequency module. 3. The method of claim 2,
The IDT electrode of the resonator connected to the output terminal of the surface acoustic wave filter is divided in the cross width direction,
Wherein the electrode parameter is a number of subdivisions in the cross width direction of the IDT electrode,
High frequency module. 3. The method of claim 2,
Wherein the electrode parameter includes a first main wavelength which is an average value of a main wavelength of the resonator connected to an input terminal of the surface acoustic wave filter and a second main wavelength which is an average value of a main wavelength of the resonator connected to an output terminal of the surface acoustic wave filter Which is an average value of the first main wavelength,
Wherein the first main wavelength and the second main wavelength are different,
High frequency module. 8. The method of claim 7,
Wherein the electrode parameter is set such that the resonance frequency of the main surface of the resonator connected to the output terminal of the surface acoustic wave filter with respect to the first main wavelength which is an average value of the main wavelength of the resonator connected to the input terminal of the surface- Is a main wave equipment having a ratio of a second main wavelength which is an average value of wavelengths,
Wherein the main wave equipment is 1.01 or more,
High frequency module. 3. The method of claim 2,
Wherein the electrode parameter is a main duty of the resonator connected to an output terminal of the surface acoustic wave filter,
Wherein the main duty is greater than 0.55 and less than 0.75,
High frequency module. The method according to claim 1,
In the above-described surface acoustic wave filter, the wiring between the IDT electrode of the resonator connected to the output terminal of the surface acoustic wave filter and the output terminal of the surface acoustic wave filter is formed on the interlayer insulating film formed on the substrate,
High frequency module. 11. The method of claim 10,
The IDT electrode of the resonator connected to the output terminal of the SAW filter has a first electrode layer formed on the substrate and a second electrode layer formed on the first electrode layer,
Wherein the wiring at the position where the interlayer insulating film is disposed includes the first electrode layer and the second electrode layer,
High frequency module. 11. The method of claim 10,
The IDT electrode of the resonator connected to the output terminal of the surface acoustic wave filter has a first electrode layer formed on the substrate and a second electrode layer formed on the first electrode layer,
Wherein the wiring at a position where the interlayer insulating film is disposed includes a second electrode layer formed on the interlayer insulating film,
High frequency module.

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