WO2020262023A1 - 複合フィルタ装置 - Google Patents
複合フィルタ装置 Download PDFInfo
- Publication number
- WO2020262023A1 WO2020262023A1 PCT/JP2020/023074 JP2020023074W WO2020262023A1 WO 2020262023 A1 WO2020262023 A1 WO 2020262023A1 JP 2020023074 W JP2020023074 W JP 2020023074W WO 2020262023 A1 WO2020262023 A1 WO 2020262023A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- filter
- frequency
- pass band
- band
- filter device
- Prior art date
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 36
- 239000000758 substrate Substances 0.000 claims abstract description 44
- 230000005855 radiation Effects 0.000 claims description 41
- 229910013641 LiNbO 3 Inorganic materials 0.000 claims description 19
- 239000007772 electrode material Substances 0.000 claims description 15
- 229910052697 platinum Inorganic materials 0.000 claims description 7
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 229910052741 iridium Inorganic materials 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 229910052750 molybdenum Inorganic materials 0.000 claims description 2
- 229910052715 tantalum Inorganic materials 0.000 claims description 2
- 238000003780 insertion Methods 0.000 abstract description 14
- 230000037431 insertion Effects 0.000 abstract description 14
- 229910003327 LiNbO3 Inorganic materials 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 11
- 230000000052 comparative effect Effects 0.000 description 9
- 230000005540 biological transmission Effects 0.000 description 8
- 230000002776 aggregation Effects 0.000 description 4
- 238000004220 aggregation Methods 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229910052814 silicon oxide Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- -1 for example Chemical compound 0.000 description 1
- YBMRDBCBODYGJE-UHFFFAOYSA-N germanium oxide Inorganic materials O=[Ge]=O YBMRDBCBODYGJE-UHFFFAOYSA-N 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- PVADDRMAFCOOPC-UHFFFAOYSA-N oxogermanium Chemical compound [Ge]=O PVADDRMAFCOOPC-UHFFFAOYSA-N 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
- H03H9/56—Monolithic crystal filters
- H03H9/566—Electric coupling means therefor
- H03H9/568—Electric coupling means therefor consisting of a ladder configuration
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/125—Driving means, e.g. electrodes, coils
- H03H9/145—Driving means, e.g. electrodes, coils for networks using surface acoustic waves
- H03H9/14538—Formation
- H03H9/14541—Multilayer finger or busbar electrode
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/64—Filters using surface acoustic waves
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/02535—Details of surface acoustic wave devices
- H03H9/02543—Characteristics of substrate, e.g. cutting angles
- H03H9/02559—Characteristics of substrate, e.g. cutting angles of lithium niobate or lithium-tantalate substrates
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/02535—Details of surface acoustic wave devices
- H03H9/02818—Means for compensation or elimination of undesirable effects
- H03H9/02866—Means for compensation or elimination of undesirable effects of bulk wave excitation and reflections
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/125—Driving means, e.g. electrodes, coils
- H03H9/13—Driving means, e.g. electrodes, coils for networks consisting of piezoelectric or electrostrictive materials
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/125—Driving means, e.g. electrodes, coils
- H03H9/145—Driving means, e.g. electrodes, coils for networks using surface acoustic waves
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
- H03H9/205—Constructional features of resonators consisting of piezoelectric or electrostrictive material having multiple resonators
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/25—Constructional features of resonators using surface acoustic waves
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/64—Filters using surface acoustic waves
- H03H9/6423—Means for obtaining a particular transfer characteristic
- H03H9/6433—Coupled resonator filters
- H03H9/6483—Ladder SAW filters
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/70—Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
- H03H9/72—Networks using surface acoustic waves
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/70—Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
- H03H9/72—Networks using surface acoustic waves
- H03H9/725—Duplexers
Definitions
- the present invention relates to a composite filter device in which one ends of a plurality of filters are commonly connected to each other.
- a composite filter device using an elastic wave filter is widely used.
- the first filter consists of a ladder type filter.
- This ladder type filter has a plurality of series arm resonators composed of elastic wave resonators and a plurality of parallel arm resonators composed of elastic wave resonators.
- the bulk wave radiation frequency of the series arm resonator closest to the antenna terminal is set higher than the pass band of the second filter. As a result, the insertion loss of the second filter is reduced.
- An object of the present invention is to provide a composite filter device having first and second filters, which can further reduce the insertion loss in the second filter having a high relative pass band. There is.
- the composite filter device includes a piezoelectric substrate which is a LiNbO 3 substrate, a first filter which is configured on the piezoelectric substrate and includes a plurality of resonators each of which is an elastic wave resonator, and the first filter.
- a first filter and a second filter having one end connected in common are provided, and the pass band of the second filter is in a frequency band higher than the pass band of the first filter, and the first filter is provided.
- This is a composite filter device in which the bulk wave emission frequencies of all the resonators constituting the filter are higher than the pass band of the second filter.
- the insertion loss in the pass band of the second filter which has a higher pass band than the first filter, can be further reduced.
- FIG. 1 is a circuit diagram of a composite filter device as an embodiment of the present invention.
- FIG. 2 is a front sectional view for explaining an elastic wave resonator used in one embodiment of the present invention.
- 3 (a) and 3 (b) are diagrams showing impedance characteristics and phase characteristics of a general elastic wave resonator using LiNbO 3 of rotational Y-cut X propagation.
- FIG. 4 is a diagram showing each filter characteristic of Examples, Comparative Examples, and a single filter.
- 5 (a) and 5 (b) are diagrams showing impedance characteristics and phase characteristics of the elastic wave resonator according to the reference example.
- FIG. 6 (a) and 6 (b) are diagrams showing impedance characteristics and phase characteristics of the elastic wave resonator used in one embodiment of the present invention.
- FIG. 7 is a diagram showing the relationship between the film thickness of the electrode layer made of Pt of the IDT electrode, that is, the Pt film thickness and the frequency ratio.
- FIG. 8 is a diagram showing the relationship between the film thickness of the electrode layer made of Au of the IDT electrode, that is, the Au film thickness and the frequency ratio.
- FIG. 9 is a diagram showing the relationship between the film thickness of the electrode layer made of W of the IDT electrode, that is, the W film thickness and the frequency ratio.
- FIG. 7 is a diagram showing the relationship between the film thickness of the electrode layer made of Pt of the IDT electrode, that is, the Pt film thickness and the frequency ratio.
- FIG. 8 is a diagram showing the relationship between the film thickness of the electrode layer made of Au of the IDT electrode, that is, the Au film thickness and the frequency ratio.
- FIG. 9 is
- FIG. 10 is a diagram showing the relationship between the film thickness of the electrode layer made of Ir of the IDT electrode, that is, the Ir film thickness and the frequency ratio.
- FIG. 11 is a diagram showing the relationship between the cut angle of the Y-cut X propagation LiNbO 3 substrate and the electromechanical coupling coefficient of the unwanted wave.
- FIG. 1 is a circuit diagram of a composite filter device as an embodiment of the present invention.
- the composite filter device 1 is used as a multiplexer in the RF stage of a smartphone, for example.
- the number of a plurality of filters connected to the antenna terminal ANT is not particularly limited as long as the first filter 2 and the second filter 3 are included. That is, the number of the plurality of filters may be 2 or 3, or 5 or more.
- the first to fourth filters 2 to 5 are bandpass type filters.
- the pass band of the second filter 3 is higher than the pass band of the first filter 2.
- the first filter 2 is a ladder type filter having a plurality of elastic wave resonators.
- the first filter 2 is, for example, a transmission filter having a transmission terminal 10.
- a plurality of series arm resonators S11 to S14 are provided on the series arm connecting the transmission terminal 10 and the antenna terminal ANT.
- Parallel arm resonators P11 to P13 are provided in each of the plurality of parallel arms connecting the series arm and the ground potential.
- the series arm resonators S11 to S14 and the parallel arm resonators P11 to P13 are made of elastic wave resonators.
- FIG. 2 is a front sectional view for explaining an elastic wave resonator used in one embodiment of the present invention.
- the elastic wave resonator 21 has a piezoelectric substrate 22 which is a LiNbO 3 substrate.
- the IDT electrode 24 and the reflectors 25 and 26 are provided on the piezoelectric substrate 22. As a result, a 1-port type elastic wave resonator is constructed.
- a dielectric film 27 is laminated so as to cover the IDT electrode 24 and the reflectors 25 and 26.
- the dielectric film 27 is made of silicon oxide.
- the dielectric film 27 may be made of a dielectric other than silicon oxide, for example, SiO x N y , glass, germanium oxide, or the like.
- the series arm resonators S11 to S14 and the parallel arm resonators P11 to P13 in the first filter 2 shown in FIG. 1 are composed of such elastic wave resonators 21.
- the second filter 3 is a band-passing type filter, and this configuration is not particularly limited, but the frequency of the passing band is higher than the passing band of the first filter 2.
- the pass bands of the third and fourth filters 4 and 5 are in a frequency band different from the pass bands of the first and second filters 2 and 3.
- the pass bands of the third and fourth filters 4 and 5 are also different from each other.
- the feature of the composite filter device 1 is that all the resonators constituting the first filter 2, that is, the bulk wave emission frequencies of the series arm resonators S11 to S14 and the parallel arm resonators P11 to P13 are second. This is because the frequency position is set higher than the pass band of the filter 3 of. Thereby, the insertion loss in the pass band of the second filter 3 can be further reduced. This will be described more specifically by giving the following examples and comparative examples.
- the first filter 2 is a band 1 transmission filter used in LTE
- the second filter 3 is a band 1 reception filter.
- the pass band is as follows.
- First filter 2 band 1 transmission filter, pass band 1920 MHz to 1980 MHz Second filter 3; band 1 reception filter, pass band 2110 MHz to 2170 MHz
- the bulk wave radiation frequencies of all the resonators used are set to higher frequencies than the pass band of the second filter 3. Set to.
- the main response used is the response by the love wave.
- the bulk wave radiation frequency is a frequency corresponding to the sound velocity of the slow transverse wave bulk wave of the piezoelectric substrate 22.
- the bulk wave radiation frequency is represented by Vb / ⁇ .
- Vb is about 4030 m / sec.
- the bulk wave radiation frequency of the series arm resonator S14 closest to the antenna terminal ANT was set at a frequency position higher than the pass band of the second filter 3.
- the bulk wave radiation frequencies of the other resonators, that is, the series arm resonators S11 to S13 and the parallel arm resonators P11 to P13, were set at frequency positions lower than those within the pass band or the pass band of the second filter 3.
- FIG. 4 shows the filter characteristics of the above-mentioned Examples and Comparative Examples.
- the solid line shows the filter characteristics of the example, and the alternate long and short dash line shows the filter characteristics of the comparative example.
- the broken line also shows the filter characteristics of the second filter 3 alone.
- the filter characteristic of the second filter 3 alone is a measurement of the filter characteristic of only the second filter 3 in a state where the first filter 2 is not connected to the antenna terminal.
- the insertion loss in the pass band of the second filter in the composite filter device of the comparative example is larger than the insertion loss in the pass band of the second filter in the composite filter device 1 of the embodiment. It has become. Further, it can be seen that the insertion loss in the pass band of the second filter in the composite filter device 1 of the embodiment is substantially the same as the insertion loss in the pass band of the second filter 3 alone. This is considered to be due to the following reasons.
- FIGS. 3A and 3B show the impedance characteristics and phase characteristics of an elastic wave resonator using a general love wave formed on a LiNbO 3 substrate of rotational Y-cut X propagation.
- the horizontal axis represents the speed of sound, which is the product of frequency and wavelength.
- the impedance characteristics and the phase characteristics are disturbed in the frequency range higher than the antiresonance frequency.
- This turbulence is due to the radiation of bulk waves.
- the arrow A in FIG. 3 is the position of the sound velocity Vb corresponding to the bulk wave radiation frequency, and is about 4030 m / sec, which is the sound velocity of the slow transverse wave bulk wave of the rotating Y-cut X propagation LiNbO 3 . From the position indicated by the arrow A to the hypersonic side, the response by the radiation of the bulk wave appears. This is considered to be due to the loss due to the radiation of elastic waves into the piezoelectric substrate.
- the elastic wave in the frequency range higher than the frequency corresponding to the sound velocity of the slow transverse wave bulk wave of the piezoelectric substrate, the elastic wave cannot be confined to the surface of the piezoelectric substrate or its vicinity and is radiated into the piezoelectric substrate. It is considered that this is due to the loss.
- the frequency corresponding to the sound velocity Vb of the slow transverse wave bulk wave of this piezoelectric substrate, that is, Vb / ⁇ is called the bulk wave radiation frequency as described above.
- the resonance frequency and antiresonance frequency change, but the bulk wave radiation frequency is determined only by the wavelength ⁇ determined by the pitch between the piezoelectric substrate and the electrode finger. It does not change. That is, the interval between the resonance frequency or the antiresonance frequency and the bulk wave radiation frequency changes depending on the material and film thickness of the IDT electrode.
- the series arm resonator S14 closest to the antenna terminal ANT is higher than the pass band of the second filter 3 of 2110 MHz to 2170 MHz, the series arm resonator S14 There is no loss in the pass band of the second filter 3 due to bulk wave radiation.
- the bulk wave radiation frequencies of the other series arm resonators S11 to S13 and the parallel arm resonators P11 to P13 are in the pass band of the second filter 3 or in a frequency range lower than the pass band. Therefore, as described above, it is considered that the insertion loss is exacerbated.
- the bulk wave radiation frequencies of all the resonators that is, the series arm resonators S11 to S14 and the parallel arm resonators P11 to P13 are higher than the pass band of the second filter 3. It is in the frequency range. Therefore, the insertion loss in the pass band in the second filter 3 can be reduced.
- the wavelengths of the series arm resonator S14 closest to the antenna end and the other series arm resonators S11 to S13 may be significantly different, and the resonance frequency may also be different. That is, since the resonance frequency of the series arm resonator S14 may be located on the high frequency side of the pass band of the first filter, there is also a problem that the characteristics of the first filter are likely to deteriorate.
- the ratio of the resonance frequency to the bulk wave radiation frequency is increased as described later. Thereby, the resonance frequencies of all the series arm resonators can be brought close to each other and arranged in the pass band of the first filter 2. Therefore, the characteristics of the first filter 2 are less likely to deteriorate.
- the first filter 2 and the second filter 3 may be configured on the same piezoelectric substrate, and the second filter 3 is a piezoelectric substrate different from the piezoelectric substrate constituting the first filter 2. It may be configured by using a substrate. Further, the second filter 3 may be an elastic wave that does not use a piezoelectric substrate, or may be a filter that does not use an elastic wave such as an LC filter.
- At least one other filter such as the third, fourth filters 4, 5 and the like is the first and second filters. It may be commonly connected to a few. In this case, in the composite filter device 1, at least three filters are commonly connected, and the pass band of the second filter 3 is located on the highest frequency side among the pass bands of all the filters. preferable. In this case, the deterioration of the insertion loss due to the bulk wave radiation of the first filter 2 is unlikely to occur in the filters other than the first and second filters 2 and 3.
- the pass band of the first filter 2 may be the lowest among the pass bands of all the filters.
- the ratio of the bulk wave radiation frequency to the resonance frequency of the resonator having the lowest resonance frequency among the plurality of resonators constituting the first filter is 1.4 or more. Is preferable. In the composite filter device according to the present invention, it is more preferable that the ratio of the bulk wave radiation frequency to the resonance frequency of all the resonators constituting the first filter is 1.4 or more.
- the ratio of the bulk wave radiation frequency to the resonance frequency is preferably 2.0 or less. As will be described later, the ratio of the bulk wave radiation frequency to the resonance frequency increases as the film thickness of the main electrode increases, but if the film thickness of the main electrode becomes too thick, it becomes difficult to form an electrode or a dielectric film. Because.
- the present invention can be applied to various combinations of the first filter and the second filter as long as the ratio of the bulk wave radiation frequency to the resonance frequency is 1.4 or more. This will be described below.
- CA carrier aggregation
- band-passing filters of different bands are commonly connected.
- the reception filter and the reception filter of the same band are commonly connected.
- band-passing filters of different bands there are combinations in which the frequencies of the pass bands are far apart. Table 1 below shows typical examples of band combinations used for carrier aggregation and the pass band of the reception band of each band.
- the band in which the pass band of the transmission filter and the pass band of the reception filter are farthest from each other is band 4.
- band 4 the ratio of the center frequency of the pass band of the reception filter to the center frequency of the pass band of the transmission filter was 1.23.
- carrier aggregation two band-passing filters having a larger frequency ratio relationship may be connected to the antenna terminal. Therefore, for example, in the elastic wave resonator used in the first filter, it is preferable to make the ratio of the bulk wave radiation frequency to the resonance frequency larger than before.
- the ratio of the bulk wave radiation frequency to the resonance frequency when the ratio of the bulk wave radiation frequency to the resonance frequency is increased to 1.4, it can be applied to a combination of band-passing filters in which the ratio of the center frequency of the pass band is 1.4 or less.
- a combination of receiving filters such as band 1 and band 7, band 2 and band 7, or band 39 and band 41.
- the ratio of the bulk wave radiation frequency to the resonance frequency of the main response is increased to 1.5, it is possible to deal with a combination of bands having a center frequency ratio of 1.5 or less.
- FIGS. 5 (a) and 5 (b) show the impedance characteristics and phase characteristics of the elastic wave resonator using the love wave of the following design parameters.
- the wavelength ⁇ 2.375 ⁇ m.
- 4030 m / sec which is the value of LiNbO 3 of rotational Y-cut X propagation, was used.
- the resonance frequency of the main response using the love wave is 1486 MHz.
- the bulk wave radiation frequency is 1697 MHz. Therefore, the frequency ratio, which is the ratio of the bulk wave radiation frequency to the resonance frequency, is 1.142.
- this elastic wave resonator is used as the elastic wave resonator of the reception filter of band 11.
- the bulk wave emission frequency exists in a frequency range lower than the pass band of band 1. Therefore, the loss may be exacerbated in the second filter, which is the band 1 reception filter.
- an elastic wave resonator having a ratio of the bulk wave radiation frequency to the resonance frequency of 1.515 was created with the following design parameters.
- the impedance characteristics and phase characteristics of this elastic wave resonator are shown in FIGS. 6 (a) and 6 (b).
- the wavelength ⁇ of the love wave was 1.790 ⁇ m.
- the resonance frequency of the love wave response appears at 1486 MHz.
- the bulk wave radiation frequency is 2252 MHz. Therefore, the frequency ratio, which is the ratio of the bulk wave radiation frequency to the resonance frequency, is 1.515.
- the above elastic wave resonator When the above elastic wave resonator is used as the elastic wave resonator of the receiving filter of band 11, the bulk wave radiation frequency exists in a frequency range higher than the pass band of band 1. Therefore, the loss in the band 1 reception filter can be remarkably reduced, and good filter characteristics can be obtained.
- the ratio of the bulk wave radiation frequency to the resonance frequency of the main response of the elastic wave resonator is preferably 1.4 or more, and more preferably 1.5 or more.
- a high-density metal may be used for the IDT electrode, and the thickness thereof may be increased.
- Preferred examples of such an electrode material include Pt, Au, W, Ir, Ta, Mo and Cu.
- the IDT electrode is made of these dense metals, but the IDT electrode may be laminated with an electrode layer made of another metal as long as these metals are used as the main electrode material.
- the main electrode material is an electrode material that mainly acts to excite elastic waves used in the IDT electrode, and refers to an electrode material that occupies 50% by weight or more of the total metal constituting the IDT electrode. And.
- FIGS. 7 to 10 show the relationship between the Pt film thickness, Au film thickness, W film thickness or Ir film thickness and the frequency ratio when a Pt, Au, W or Ir film is used as the material of the IDT electrode. ..
- the frequency ratio can be 1.4 or more when the Pt film thickness is 0.072 ⁇ or more. Further, it can be seen that the thickness at which the frequency ratio is 1.5 or more is 0.092 ⁇ or more.
- the frequency ratio is 1.4 or more when the Au film thickness is 0.072 ⁇ or more, and 1.5 or more. Is 0.090 ⁇ or more.
- the main electrode material is W
- the frequency ratio of 1.4 or more is 0.088 ⁇ or more, and 1.5 or more is 0.116 ⁇ or more. ..
- the frequency ratio of 1.4 or more is 0.076 ⁇ or more, and 1.5 or more is 0.10 ⁇ or more.
- the frequency ratio can be set to 1.4 or more or 1.5 or more by correcting this film thickness according to the type of main electrode material.
- FIG. 11 shows the relationship between the cut angle of the Y-cut X propagation LiNbO 3 substrate and the electromechanical coupling coefficient of the unwanted wave.
- the unnecessary wave is a spurious generated by the excitation of the Rayleigh wave in the vicinity of the resonance frequency-anti-resonance frequency band in the elastic wave resonator using the love wave, and the spurious caused by the Rayleigh wave may be generated.
- the electromechanical coupling coefficient of the Rayleigh wave changes. Therefore, it is preferable to set the cut angle in the range of 3 ° or more and 26 ° or less. In this case, the electromechanical coupling coefficient of the unwanted wave can be set to 0.1% or less.
- the orientation of LiNbO 3 used for the piezoelectric substrate is described as ⁇ ° rotation Y-cut X propagation.
- the first and third Euler angles which are 0 °, may be in the range of ⁇ 5 ° or more and 5 ° or less.
- the electrical characteristics are the same even when the direction of the crystal axis of the LiNbO 3 used is opposite. Therefore, a piezoelectric substrate using LiNbO 3 having Euler angles (0 °, ⁇ + 90 °, 0 °) may be used. In this case, when expressed in terms of cut angle, ( ⁇ -180) ° rotation Y cut X propagation.
- the first filter 2 has series arm resonators S11 to S14 and parallel arm resonators P11 to P13, but the number of resonators in the ladder type filter is not limited to this. Absent.
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
Abstract
Description
第2のフィルタ3;バンド1の受信フィルタ、通過帯域2110MHz~2170MHz
直列腕共振子S11~S14;電極指ピッチで定まる波長λ=1.440μm、バルク波放射周波数位置は2799MHz
並列腕共振子P11~P13;電極指ピッチで定まる波長λ=1.605μm、バルク波放射周波数位置は2511MHz
直列腕共振子S14;電極指ピッチで定まる波長λ=1.832μm、バルク波放射周波数位置は2200MHz
直列腕共振子S11~S13;電極指ピッチで定まる波長λ=1.883μm、バルク波放射周波数位置は2140MHz
並列腕共振子P11~P13;電極指ピッチで定まる波長λ=1.965μm、バルク波放射周波数位置は2051MHz
IDT電極;Ptからなる電極、Pt膜厚=0.025λ
SiO2膜厚;0.30λ
IDT電極;Ptからなる電極、Pt膜厚=0.095λ
SiO2膜厚;0.30λ
2~5…第1~第4のフィルタ
10…送信端子
21…弾性波共振子
22…圧電基板
24…IDT電極
25,26…反射器
27…誘電体膜
P11~P13…並列腕共振子
S11~S14…直列腕共振子
Claims (12)
- LiNbO3基板である圧電基板と、
前記圧電基板上に構成されており、それぞれが弾性波共振子からなる複数の共振子を含む第1のフィルタと、
前記第1のフィルタと一端同士が共通接続されている第2のフィルタと、
を備え、
前記第2のフィルタの通過帯域が、前記第1のフィルタの通過帯域よりも高い周波数帯域にあり、
前記第1のフィルタを構成している全ての前記共振子のバルク波放射周波数が、前記第2のフィルタの通過帯域より高い、複合フィルタ装置。 - 前記第1のフィルタを構成している複数の前記共振子の内、最も低い共振周波数を有する共振子において、バルク波放射周波数の共振周波数に対する比が1.4以上である、請求項1に記載の複合フィルタ装置。
- 前記第1のフィルタを構成している前記共振子の全てにおいて、バルク波放射周波数の共振周波数に対する比が、1.4以上である、請求項1または2に記載の複合フィルタ装置。
- 前記第1のフィルタを構成している前記共振子の全てが、前記圧電基板上に設けられた同じIDT電極を有し、
前記IDT電極が複数本の電極指を有し、電極指ピッチで定まる波長がλであり、
前記IDT電極の主電極材料が、Pt、Au、W、Ir、Ta、Mo及びCuからなる群から選択された1種の金属を主成分とする、請求項1~3のいずれか1項に記載の複合フィルタ装置。 - 前記第1のフィルタが、前記IDT電極を覆うように設けられた誘電体膜を備える、請求項4に記載の複合フィルタ装置。
- 前記IDT電極の主電極材料がPtであり、前記Ptからなる電極層の厚みが、0.072λ以上である、請求項4に記載の複合フィルタ装置。
- 前記IDT電極の主電極材料がAuであり、前記Auからなる電極層の厚みが、0.072λ以上である、請求項4に記載の複合フィルタ装置。
- 前記IDT電極の主電極材料がWであり、前記Wからなる電極層の厚みが、0.088λ以上である、請求項4に記載の複合フィルタ装置。
- 前記IDT電極の主電極材料がIrであり、前記Irからなる電極層の厚みが、0.076λ以上である、請求項4に記載の複合フィルタ装置。
- 前記圧電基板が、3°~26°回転YカットX伝搬のLiNbO3基板である、請求項1~9のいずれか1項に記載の複合フィルタ装置。
- 前記第1のフィルタ及び前記第2のフィルタに加えて、少なくとも1つの他のフィルタが前記第1,第2のフィルタと共通接続されており、前記第2のフィルタの通過帯域が、全てのフィルタの通過帯域の中で最も高域側に位置している、請求項1~10のいずれか1項に記載の複合フィルタ装置。
- 前記第1のフィルタ及び前記第2のフィルタに加えて、少なくとも1つの他のフィルタが前記第1,第2のフィルタと共通接続されており、前記第1のフィルタの通過帯域が、全てのフィルタの通過帯域の中で最も低い、請求項1~11のいずれか1項に記載の複合フィルタ装置。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202080040743.5A CN113940003A (zh) | 2019-06-24 | 2020-06-11 | 复合滤波器装置 |
KR1020217039147A KR20220002618A (ko) | 2019-06-24 | 2020-06-11 | 복합 필터 장치 |
JP2021528163A JP7218807B2 (ja) | 2019-06-24 | 2020-06-11 | 複合フィルタ装置 |
US17/557,090 US12040782B2 (en) | 2019-06-24 | 2021-12-21 | Composite filter device |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2019-116417 | 2019-06-24 | ||
JP2019116417 | 2019-06-24 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US17/557,090 Continuation US12040782B2 (en) | 2019-06-24 | 2021-12-21 | Composite filter device |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2020262023A1 true WO2020262023A1 (ja) | 2020-12-30 |
Family
ID=74060276
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2020/023074 WO2020262023A1 (ja) | 2019-06-24 | 2020-06-11 | 複合フィルタ装置 |
Country Status (4)
Country | Link |
---|---|
JP (1) | JP7218807B2 (ja) |
KR (1) | KR20220002618A (ja) |
CN (1) | CN113940003A (ja) |
WO (1) | WO2020262023A1 (ja) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2009147787A1 (ja) * | 2008-06-06 | 2009-12-10 | パナソニック株式会社 | 弾性波共用器 |
JP2016184900A (ja) * | 2015-03-26 | 2016-10-20 | 株式会社村田製作所 | 弾性表面波フィルタ |
WO2017217197A1 (ja) * | 2016-06-14 | 2017-12-21 | 株式会社村田製作所 | マルチプレクサ、高周波フロントエンド回路および通信装置 |
-
2020
- 2020-06-11 KR KR1020217039147A patent/KR20220002618A/ko not_active Application Discontinuation
- 2020-06-11 CN CN202080040743.5A patent/CN113940003A/zh active Pending
- 2020-06-11 WO PCT/JP2020/023074 patent/WO2020262023A1/ja active Application Filing
- 2020-06-11 JP JP2021528163A patent/JP7218807B2/ja active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2009147787A1 (ja) * | 2008-06-06 | 2009-12-10 | パナソニック株式会社 | 弾性波共用器 |
JP2016184900A (ja) * | 2015-03-26 | 2016-10-20 | 株式会社村田製作所 | 弾性表面波フィルタ |
WO2017217197A1 (ja) * | 2016-06-14 | 2017-12-21 | 株式会社村田製作所 | マルチプレクサ、高周波フロントエンド回路および通信装置 |
Also Published As
Publication number | Publication date |
---|---|
JPWO2020262023A1 (ja) | 2020-12-30 |
US20220116022A1 (en) | 2022-04-14 |
CN113940003A (zh) | 2022-01-14 |
KR20220002618A (ko) | 2022-01-06 |
JP7218807B2 (ja) | 2023-02-07 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2018168836A1 (ja) | 弾性波素子、弾性波フィルタ装置およびマルチプレクサ | |
JP5182459B2 (ja) | ラダー型弾性波フィルタ及びこれを用いたアンテナ共用器 | |
JP5033876B2 (ja) | 弾性表面波装置及び通信装置 | |
WO2009147787A1 (ja) | 弾性波共用器 | |
WO2009119007A1 (ja) | 弾性波フィルタ装置 | |
JP6620908B2 (ja) | マルチプレクサ、高周波フロントエンド回路及び通信装置 | |
JP6777240B2 (ja) | マルチプレクサ、高周波フロントエンド回路及び通信装置 | |
JP6964603B2 (ja) | マルチプレクサ、高周波フロントエンド回路及び通信装置 | |
WO2018116602A1 (ja) | 弾性波装置、高周波フロントエンド回路及び通信装置 | |
JP2019068309A (ja) | 弾性波デバイス、フィルタおよびマルチプレクサ | |
JPWO2011102128A1 (ja) | アンテナ共用器 | |
JP2017228945A (ja) | 弾性波共振器、フィルタおよびマルチプレクサ | |
US11063202B2 (en) | Elastic wave device | |
US8106725B2 (en) | Acoustic wave filter device | |
JP5810113B2 (ja) | 弾性波共振器とこれを用いた弾性波フィルタおよびアンテナ共用器 | |
JP6624337B2 (ja) | 弾性波装置、マルチプレクサ、高周波フロントエンド回路及び通信装置 | |
JP6465441B2 (ja) | マルチプレクサ | |
WO2020050401A1 (ja) | 弾性波装置、高周波フロントエンド回路及び通信装置 | |
WO2017068877A1 (ja) | 弾性波装置、高周波フロントエンド回路及び通信装置 | |
WO2020262023A1 (ja) | 複合フィルタ装置 | |
JPWO2010125934A1 (ja) | 弾性波装置 | |
US12040782B2 (en) | Composite filter device | |
WO2020050402A1 (ja) | 弾性波装置、弾性波フィルタ及び複合フィルタ装置 | |
JP2006129057A (ja) | 弾性表面波装置 | |
WO2023080167A1 (ja) | フィルタ装置及びマルチプレクサ |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 20831672 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2021528163 Country of ref document: JP Kind code of ref document: A |
|
ENP | Entry into the national phase |
Ref document number: 20217039147 Country of ref document: KR Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 20831672 Country of ref document: EP Kind code of ref document: A1 |