WO2013065488A1 - Résonateur acoustique en volume à film, dispositif de filtrage et duplexeur - Google Patents

Résonateur acoustique en volume à film, dispositif de filtrage et duplexeur Download PDF

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Publication number
WO2013065488A1
WO2013065488A1 PCT/JP2012/076836 JP2012076836W WO2013065488A1 WO 2013065488 A1 WO2013065488 A1 WO 2013065488A1 JP 2012076836 W JP2012076836 W JP 2012076836W WO 2013065488 A1 WO2013065488 A1 WO 2013065488A1
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Prior art keywords
thin film
piezoelectric thin
resonator
resonators
aluminum nitride
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PCT/JP2012/076836
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English (en)
Japanese (ja)
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圭一 梅田
高志 三宅
聖人 荒木
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株式会社村田製作所
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Publication of WO2013065488A1 publication Critical patent/WO2013065488A1/fr

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    • 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
    • H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
    • H03H9/171—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type
    • H03H9/172—Means for mounting on a substrate, i.e. means constituting the material interface confining the waves to a volume
    • H03H9/173—Air-gaps
    • 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
    • H03H9/02007—Details of bulk acoustic wave devices
    • H03H9/02086—Means for compensation or elimination of undesirable effects
    • H03H9/02102—Means for compensation or elimination of undesirable effects of temperature influence
    • 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
    • H03H9/02007—Details of bulk acoustic wave devices
    • H03H9/02086—Means for compensation or elimination of undesirable effects
    • H03H9/02149—Means for compensation or elimination of undesirable effects of ageing changes of characteristics, e.g. electro-acousto-migration
    • 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
    • H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
    • H03H9/171—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type
    • H03H9/172—Means for mounting on a substrate, i.e. means constituting the material interface confining the waves to a volume
    • H03H9/175—Acoustic mirrors
    • 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
    • H03H9/542—Filters comprising resonators of piezoelectric or electrostrictive material including passive elements
    • 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
    • H03H9/58—Multiple crystal filters
    • H03H9/60—Electric coupling means therefor
    • H03H9/605—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
    • H03H9/70—Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
    • H03H9/703—Networks using bulk acoustic wave devices
    • H03H9/706—Duplexers

Definitions

  • the present invention relates to a piezoelectric thin film resonator and a filter device using an aluminum nitride-based material, and more particularly to a piezoelectric thin film resonator, a filter device and a duplexer using an aluminum nitride film containing Sc.
  • Patent Document 1 discloses a method of manufacturing a piezoelectric thin film used for such a piezoelectric thin film resonator. That is, Patent Document 1 discloses a method of sputtering aluminum and scandium at a substrate temperature in the range of 5 ° C. to 450 ° C. in a nitrogen gas atmosphere. Accordingly, it is described that the content of scandium can be in the range of 0.5 to 50 atomic% and the piezoelectric response can be improved. In Patent Document 1, the scandium content in the Sc-containing aluminum nitride thin film is 0.5 to 50 atomic% as described above, and is preferably in the range of 35 to 43 atomic%, and is preferably 43 atomic%. Most preferred.
  • An object of the present invention is to provide a piezoelectric thin film resonator using a Sc-containing aluminum nitride thin film, having a sufficient specific band and a small absolute value of the frequency temperature coefficient TCF.
  • Another object of the present invention is to provide a filter device and a duplexer having the piezoelectric thin film resonator as at least one resonator, having a sufficient bandwidth and good frequency temperature characteristics.
  • the piezoelectric thin film resonator according to the present invention is a piezoelectric thin film comprising a Sc-containing aluminum nitride film having an Sc concentration of 0.5 atomic% to 24 atomic% when the total number of scandium atoms and aluminum atoms is 100 atomic%.
  • a first electrode and a second electrode provided so as to be opposed to each other with the piezoelectric thin film interposed therebetween, and a substrate supporting a piezoelectric vibrating portion including the piezoelectric thin film and the first electrode and the second electrode.
  • An excitation unit in which the first and second electrodes are opposed to each other with the piezoelectric thin film interposed therebetween is disposed with a gap from the upper surface of the substrate.
  • the piezoelectric thin film resonator according to the present invention preferably further includes a protective film that covers at least a part of the piezoelectric vibrating portion.
  • the protective film is preferably made of aluminum nitride or Sc-containing aluminum nitride.
  • a filter device having a plurality of piezoelectric thin film resonators having a plurality of piezoelectric thin film resonators.
  • at least one of the plurality of piezoelectric thin film resonators is a piezoelectric thin film resonator including an aluminum nitride film not containing Sc as a piezoelectric thin film, and the remaining piezoelectric thin film resonators are It consists of a piezoelectric thin film resonator constructed according to the invention.
  • a filter device having a plurality of piezoelectric thin film resonators having a plurality of piezoelectric thin film resonators.
  • the plurality of piezoelectric thin film resonators are piezoelectric thin film resonators configured according to the present invention, and at least one piezoelectric thin film resonator is a piezoelectric thin film resonator using a fundamental wave propagating through the piezoelectric thin film.
  • at least one of the piezoelectric thin film resonators further includes a silicon oxide film laminated on a piezoelectric thin film made of an Sc-containing aluminum nitride film, and is twice the bulk wave propagating through the piezoelectric thin film Using waves.
  • a duplexer including a reception filter having a plurality of piezoelectric thin film resonators and a transmission filter having a plurality of piezoelectric thin film resonators is provided. Roll-off of the frequency gap between the pass band of the transmission filter and the pass band of the reception filter among the plurality of piezoelectric thin film resonators constituting the transmission filter and the plurality of piezoelectric thin film resonators constituting the reception filter.
  • the piezoelectric thin film resonator that determines the characteristics is a piezoelectric thin film resonator having an aluminum nitride film as a piezoelectric thin film, and the remaining piezoelectric thin film resonator is a piezoelectric thin film resonator configured according to the present invention.
  • the resonator that determines the frequency gap uses an aluminum nitride thin film that does not contain Sc, it is possible to improve the frequency temperature characteristics while improving the attenuation characteristics at the end of the passband that faces the frequency gap. it can. Moreover, since the remaining piezoelectric thin film resonators are composed of piezoelectric thin film resonators configured according to the present invention, a sufficient bandwidth and good frequency temperature characteristics can be realized. In addition, it is possible to reduce or omit the inductance required for bandwidth expansion.
  • duplexer including a reception filter having a plurality of piezoelectric thin film resonators and a transmission filter having a plurality of piezoelectric thin film resonators is provided.
  • the piezoelectric thin film resonator for determining the roll-off characteristics of the present invention further comprises a silicon oxide film laminated on a piezoelectric thin film made of an Sc-containing aluminum nitride film, and uses a double wave propagating through the piezoelectric thin film.
  • the remaining piezoelectric thin film resonators are configured in accordance with the present invention, and are composed of piezoelectric thin film resonators utilizing a fundamental wave of a bulk wave propagating through the piezoelectric thin film.
  • the scandium concentration is in the range of 0.5 atomic% to 24 atomic%, both a sufficient specific bandwidth and good frequency-temperature characteristics are achieved. It becomes possible.
  • FIG. 1 is a front sectional view of a piezoelectric thin film resonator according to a first embodiment of the present invention.
  • FIG. 2 is a diagram showing the relationship between the scandium concentration in the piezoelectric thin film resonator of the first embodiment, the specific band of the resonator, and the TCF.
  • FIG. 3 is a circuit diagram of a filter device as a second embodiment of the present invention.
  • FIG. 4 is a diagram illustrating attenuation frequency characteristics of the filter device according to the second embodiment.
  • FIG. 5 is a circuit diagram of a duplexer as a third embodiment of the present invention.
  • FIG. 6 is a circuit diagram showing a duplexer as a fourth embodiment of the present invention.
  • FIG. 1 is a front sectional view of a piezoelectric thin film resonator according to a first embodiment of the present invention.
  • FIG. 2 is a diagram showing the relationship between the scandium concentration in the piezoelectric thin film resonator of the
  • FIG. 7 is a circuit diagram of a duplexer as a fifth embodiment of the present invention.
  • FIG. 8 is a front sectional view of a piezoelectric thin film resonator as a fifth embodiment of the present invention.
  • FIG. 9 is a front sectional view of a piezoelectric thin film resonator according to a sixth embodiment of the present invention.
  • FIG. 1 is a front sectional view showing a piezoelectric thin film resonator according to a first embodiment of the present invention.
  • the piezoelectric thin film resonator 1 has a substrate 2.
  • the substrate 2 is made of an appropriate insulating material.
  • the substrate 2 is made of a Si substrate.
  • An insulating film 3 is formed on the substrate 2. Although the insulating film 3 does not necessarily need to be provided, the insulating film 3 is provided because it is necessary for a process for forming the gap A described later.
  • the insulating film 3 is made of silicon oxide in this embodiment.
  • a protective film 4 for protecting the resonator part is formed on the insulating film 3.
  • the protective film 4 is made of silicon oxide. Further, the central portion of the protective film 4 is separated from the substrate 2 and the insulating film 3 through the gap A.
  • the protective film 4 may be made of an insulating material other than silicon oxide.
  • the protective film 4 may be made of, for example, silicon oxynitride, silicon nitride, aluminum nitride, Sc-containing aluminum nitride, or the like.
  • the protective film 4 is preferably made of aluminum nitride or Sc-containing aluminum nitride.
  • a first electrode 5 is formed on the protective film 4.
  • a piezoelectric thin film 6 made of an Sc-containing aluminum nitride film is formed on the first electrode 5.
  • the Sc-containing aluminum nitride film contains Sc at a ratio of 0.5 to 24 atomic%.
  • Such an Sc-containing aluminum nitride film can be formed by sputtering using Sc and aluminum nitride as targets.
  • a second electrode 7 is laminated on the piezoelectric thin film 6. Above the gap A, the first electrode 5 and the second electrode 7 face each other with the piezoelectric thin film 6 interposed therebetween. A portion where the first electrode 5 and the second electrode 7 face each other constitutes an excitation unit. That is, when an AC voltage is applied, a bulk wave is generated by the piezoelectric effect.
  • the first electrode 5 and the second electrode 7 are made of an appropriate conductive material.
  • a conductive material metals such as Pt, Au, Ti, Mo, W, Cr, Al, Ru, or alloys thereof can be used.
  • the first electrode 5 and the second electrode 7 may be formed of a stacked metal film formed by stacking a plurality of metal films.
  • a protective film 8 is formed so as to cover the second electrode 7.
  • the protective film 8 is made of an appropriate insulating material that can protect the second electrode 7 and the piezoelectric thin film 6 made of the Sc-containing aluminum nitride film from the outside. Examples of such an insulating material include silicon oxide, silicon oxynitride, silicon nitride, aluminum nitride, and Sc-containing aluminum nitride.
  • the protective film 8 is formed of silicon oxide.
  • the protective film 4 is in close contact with the insulating film 3 around the portion where the excitation unit is provided, that is, outside the gap A. Therefore, the height of other layers stacked on the protective film 4 is also lower than that of the excitation unit.
  • first electrode pad 9 is disposed outside the portion where the gap A is provided so as to be connected to the first electrode 5.
  • electrode pad 10 electrically connected to the second electrode 7 is disposed in a region outside the portion where the gap A is provided.
  • a bulk wave propagating on the piezoelectric thin film 6 is excited by applying an alternating electric field between the first and second electrodes 5 and 7.
  • Resonance characteristics can be obtained by utilizing the resonance phenomenon caused by the fundamental wave of the bulk wave.
  • the feature of this embodiment is that Sc is contained in the range of 0.5 atomic% to 24 atomic% in the Sc-containing aluminum nitride film. Thereby, it is possible to achieve both a sufficient ratio band and good frequency temperature characteristics.
  • Sc is contained in the range of 0.5 atomic% to 24 atomic% in the Sc-containing aluminum nitride when the total number of scandium atoms and aluminum atoms is 100 atomic%. It means that the ratio of Sc is 0.5 atomic% to 24 atomic%.
  • FIG. 2 shows the relationship between the Sc concentration of the Sc-containing aluminum nitride thin film, the resonator ratio band, and the TCF in the piezoelectric thin film resonator 1 of the above embodiment. As can be seen from FIG. 2, as the Sc concentration increases, the specific band of the resonator becomes wider.
  • the frequency temperature coefficient TCF decreases as the Sc concentration increases, the frequency temperature coefficient TCF gradually decreases particularly when the Sc concentration is in the range of 0.5 atomic% to 24 atomic%. When it exceeds 24 atomic%, as is apparent from FIG. 2, the absolute value of the frequency temperature coefficient TCF increases rapidly.
  • the specific band may be about several percent. That is, it is sufficient that the specific bandwidth is about 3% to 7%. Therefore, FIG. 2 shows that the absolute value of the frequency temperature coefficient TCF can be made sufficiently small while ensuring a sufficient specific bandwidth if the Sc concentration is in the range of 0.5 to 24 atomic%.
  • the change rate of the specific band of the resonator and the change rate of the frequency temperature coefficient TCF are small. Therefore, even if the Sc concentration varies slightly due to process reasons, it is difficult for variations in the ratio band and frequency temperature coefficient TCF to occur. Therefore, the piezoelectric thin film resonator 1 having desired characteristics can be obtained stably.
  • FIG. 3 is a circuit diagram of a filter device as a second embodiment of the present invention.
  • the filter device 11 of the second embodiment has an input terminal 12 and an output terminal 13.
  • Series arm resonators S 1 to S 3 are provided on the series arm connecting the input terminal 12 and the output terminal 13.
  • the series arm resonators S1 to S3 are connected to each other in series.
  • the 1st, 2nd parallel arm which connects a serial arm and ground potential is provided.
  • the first parallel arm connects the connection point between the series arm resonators S1 and S2 and the ground potential.
  • the first parallel arm is provided with a first parallel arm resonator P1.
  • One end of the second parallel arm is connected to the connection point between the series arm resonators S2 and S3, and the other end is connected to the ground potential.
  • a parallel arm resonator P2 is provided on the second parallel arm.
  • a ladder filter including the series arm resonators S1 to S3 and the parallel arm resonators P1 and P2 is configured.
  • the parallel arm resonators P1 and P2 are composed of the piezoelectric thin film resonator 1 of the first embodiment.
  • the series arm resonators S1 to S3 are composed of a second piezoelectric thin film resonator having the same structure as the piezoelectric thin film resonator 1 except that an aluminum nitride film not containing Sc is used as the piezoelectric thin film. .
  • FIG. 4 shows the attenuation frequency characteristics of the filter device of this embodiment.
  • the resonance frequency of the parallel arm resonators P1 and P2 affects the attenuation characteristic of the end portion on the low band side of the passband. Therefore, in the present embodiment, the frequency position of the lower shoulder portion of the pass band indicated by the arrow A in FIG. 4 depends on the resonance frequency of the parallel arm resonators P1 and P2. Since the parallel arm resonators P1 and P2 use the above-described Sc-containing aluminum nitride film, the resonance frequency moves larger than that of the series arm resonators S1 to S3 due to temperature change.
  • the parallel arm resonators P1 and P2 are composed of the piezoelectric thin film resonator 1 of the above-described embodiment, the frequency position of the shoulder portion on the low pass band side can be adjusted, and the bandwidth can be expanded. Temperature characteristics can be adjusted.
  • the series arm resonators S1 to S3 are made of the piezoelectric thin film resonator of the above embodiment, and the parallel arm resonators P1 and P2 are made of an aluminum nitride film not containing Sc.
  • the frequency position of the shoulder on the high side of the pass band can be adjusted by adjusting the Sc content.
  • the frequency temperature characteristic can be improved by adjusting the Sc content.
  • At least one piezoelectric thin film resonator is configured by the piezoelectric thin film resonator according to the first embodiment, and the remaining piezoelectric thin film resonators are Sc.
  • the bandwidth can be adjusted, the bandwidth can be expanded, and the frequency-temperature characteristics can be adjusted.
  • FIG. 5 is a circuit diagram of a duplexer as a third embodiment of the present invention.
  • the duplexer 21 of this embodiment has an antenna terminal 23 connected to the antenna 22, a transmission terminal 24, and a reception terminal 25.
  • a transmission filter 26 having a ladder circuit configuration is connected between the antenna terminal 23 and the transmission terminal 24.
  • the transmission filter 26 includes a series arm that connects the antenna terminal 23 and the transmission terminal 24.
  • An inductor L1 and series arm resonators S21 to S24 are arranged on this series arm. Further, the first parallel arm that connects the connection point between the series arm resonators S21 and S22 and the ground potential, the connection point between the series arm resonator S23 and the series arm resonator S24, and the ground potential are connected.
  • a second parallel arm is configured. The first parallel arm is provided with a parallel arm resonator P21 and an inductor L2 connected in series to the parallel arm resonator P21. Similarly, in the second parallel arm, the parallel arm resonator P22 and the inductor L3 are connected in series. An inductor L4 is connected between the series arm resonator S24 and the transmission terminal 24.
  • the parallel arm resonators P21 and P22 surrounded by the broken line C are formed of the piezoelectric thin film resonator according to the first embodiment.
  • the series arm resonators S21 to S24 are composed of the above-described second piezoelectric thin film resonator that does not contain Sc.
  • the frequency position of the shoulder portion on the low pass band side can be easily adjusted, and the frequency temperature characteristic can also be adjusted.
  • the reception filter 27 has a serial arm connecting the antenna terminal 23 and the reception terminal 25.
  • a ⁇ / 4 line 28, an inductor L5, series arm resonators S31 to S33, and an inductor L6 are connected in series to the series arm.
  • the parallel arm resonator P31 and the inductor L7 are connected in series.
  • an inductor may be inserted in parallel, or another impedance matching circuit may be inserted. Inserting a parallel inductor has the effect of releasing the static electricity coming from the antenna in addition to the effect of impedance matching.
  • Second to fourth parallel arms are formed between the output terminal of the resonator S33 and the ground potential, respectively.
  • parallel arm resonators P32 to P34 are provided, respectively.
  • Inductors L8 to L10 are connected in series to the parallel arm resonators P32 to P34, respectively.
  • the reception filter 27 also has a ladder circuit configuration.
  • the series arm resonators S31 to S33 surrounded by the broken line D are the piezoelectric thin film resonators of the first embodiment.
  • the parallel arm resonators P31 to P34, which are the remaining piezoelectric thin film resonators, are composed of the second piezoelectric thin film resonator described above. Therefore, similarly to the modification of the second embodiment, the frequency position of the shoulder on the high-pass side of the filter can be easily adjusted by adjusting the Sc content rate. Further, the frequency temperature characteristic can be adjusted.
  • the duplexer 21 is a duplexer used for the Band2 communication standard.
  • the pass band of the transmission filter 26 is lower than the pass band of the reception filter 27.
  • the frequency gap between the pass band of the transmission filter 26 and the pass band of the reception filter 27 is quite small. Therefore, the frequency temperature characteristic is required to be good. That is, when the frequency characteristic changes greatly due to temperature change, the attenuation characteristic of the above-described shoulder portion of the filter characteristic deteriorates.
  • the frequency position of the shoulder of the pass band on the frequency gap side between the pass band of the transmission filter 26 and the pass band of the reception filter 27 greatly affects the filter characteristics.
  • the frequency position of the shoulder portion located on the high pass band side of the transmission filter 26 is located on the low frequency side of the frequency gap.
  • the piezoelectric thin film resonance that affects the frequency characteristics of the shoulder portion is located in the transmission filter 26, the piezoelectric thin film resonance that affects the frequency characteristics of the shoulder portion.
  • the parallel arm resonators P31 to P34 are formed of a second piezoelectric thin film resonator using an aluminum nitride film not containing Sc. Therefore, the frequency temperature characteristic is good. Therefore, it is possible to improve the filter characteristics at the low band side end of the pass band of the reception filter 27 facing the high band side of the frequency gap.
  • the piezoelectric thin film resonator that determines the roll-off characteristic of the frequency gap between the pass bands of the transmission filter 26 and the reception filter 27 is an aluminum nitride that does not contain Sc having excellent frequency temperature characteristics. It consists of a second piezoelectric thin film resonator using a film. Therefore, it is possible to improve the attenuation characteristic at the end of the passband facing the frequency gap.
  • the remaining piezoelectric thin film resonators that determine the frequency characteristics of the passband end portions that are not desired for the frequency gap are composed of the piezoelectric thin film resonators of the first embodiment using the Sc-containing aluminum nitride film having a large specific band. .
  • the inductance values of the inductors L1 to L4 and L5 to L10 necessary for expanding the bandwidth can be reduced. In some cases, these inductors L5 to L10 may be omitted.
  • FIG. 6 is a circuit diagram showing a duplexer as a fourth embodiment of the present invention.
  • the duplexer 31 of the fourth embodiment is the same as the duplexer 21 in the circuit configuration itself. Therefore, the same reference numerals are assigned to the same parts.
  • the fourth embodiment differs from the third embodiment in that the series arm resonators S21 to S24 and the parallel arm resonators P21 and P22 constituting the transmission filter 26 are the above-described second piezoelectric thin film resonators. Consists of. That is, the transmission filter 26 is constituted by a plurality of piezoelectric thin film resonators using piezoelectric thin films made of an aluminum nitride film not containing Sc.
  • the reception filter 27 the series arm resonators S31 to S33 and the parallel arm resonators P31 to P34 surrounded by a broken line E are formed of the piezoelectric thin film resonator according to the first embodiment. That is, the plurality of piezoelectric thin film resonators constituting the reception filter 27 is made of an Sc-containing aluminum nitride film containing 24 atomic% of Sc.
  • the duplexer 31 is preferably used as a filter for a so-called fourth generation mobile phone.
  • the fourth generation mobile phone the amount of downlink data communication increases. For this reason, an increase in the pass bandwidth of the reception filter 27 is strongly required.
  • the reception filter 27 is configured using a plurality of piezoelectric thin film resonators made of an Sc-containing aluminum nitride film having a large specific band. Therefore, the pass band of the reception filter 27 can be sufficiently expanded. Therefore, the inductance values of the inductors L5 to L10 necessary for expanding the bandwidth can be reduced. Alternatively, the inductors L5 to L10 can be omitted.
  • FIG. 7 is a circuit diagram showing a duplexer as a fifth embodiment of the present invention.
  • the duplexer 41 is the same as that of the third embodiment in the circuit configuration. Therefore, the same reference numerals in FIG. 7 denote the same parts as those shown in FIG.
  • This embodiment is different from the third embodiment in the following points. That is, in the duplexer 41, in the reception filter 27, the series arm resonators S21 to S24 surrounded by a fine broken line F use a double wave, and the parallel arm resonators P21 and P22 surrounded by a relatively large broken line G are provided.
  • the piezoelectric thin film resonator 1 according to the first embodiment is included.
  • the piezoelectric thin film resonator 51 has a thick silicon oxide film 52 laminated on the upper surface of the second electrode 7.
  • Other structures are the same as those of the piezoelectric thin film resonator 1. Therefore, the same reference numerals are assigned to the same parts, and the explanation given with reference to FIG. 1 is used.
  • the polarity of the temperature characteristic of the elastic constant of silicon oxide is opposite to the polarity of the temperature characteristic of the elastic constant of aluminum nitride. For this reason, the piezoelectric thin film resonator 51 having a large silicon oxide film 52 has better frequency-temperature characteristics than the piezoelectric thin film resonator 1 using the fundamental wave of the first embodiment. That is, the absolute value of TCF is reduced.
  • the series arm resonators S21 to S24 are formed of piezoelectric thin film resonators using a second harmonic, so that the frequency-temperature characteristics can be effectively improved.
  • the series arm resonators S31 to S33 are composed of the first piezoelectric thin film resonator 1 using the fundamental wave.
  • the parallel arm resonators P31 to P34 surrounded by a broken line F are composed of piezoelectric thin film resonators using the second harmonic. Therefore, it is possible to effectively suppress changes due to the temperature at the end of the passband located on the frequency gap side.
  • the parallel arm resonators P21 and P22 and the series arm resonators S31 to S34 that affect the attenuation characteristics at the end opposite to the end of the passband facing the frequency gap are composed of the piezoelectric thin film resonator 1 described above. Therefore, the bandwidth can be expanded.
  • a piezoelectric thin film resonator according to the first embodiment made of an aluminum nitride film containing Sc is prepared, and silicon oxide is used as a resonator that requires a resonance characteristic having a good temperature characteristic.
  • a piezoelectric thin film resonator using the second harmonic can be obtained by simply laminating the films. Therefore, a filter having good temperature characteristics can be easily obtained. For this reason, a duplexer can be produced at a lower cost.
  • the air gap A is provided, so that the vibration of the excitation unit is hardly hindered.
  • the piezoelectric thin film resonator used in the present invention may not have the gap A.
  • FIG. 9 is a schematic front sectional view showing such a piezoelectric thin film resonator as a sixth embodiment of the present invention.
  • the gap A is not provided, and the acoustic reflection layer 62 is provided between the first electrode 5 and the substrate 2.
  • the acoustic reflection layer 62 has a structure in which relatively high acoustic impedance layers 62a and 62c and relatively low acoustic impedance layers 62b and 62d are alternately stacked.
  • the piezoelectric thin film is made of an Sc-containing aluminum nitride film in the same manner as in the first embodiment, so that it is the same as in the first embodiment. In addition, it is possible to improve the frequency temperature characteristics while securing a sufficient ratio band.
  • the transmission device and the reception filter of the filter device and the duplexer according to the present invention are not limited to the ladder circuit configuration, and can be widely applied to filters using various piezoelectric thin film resonators.
  • Silicon oxide film 61 Piezoelectric thin film resonator 62 ... Acoustic reflection layer 62a, 62b, 62c, 62d ... Acoustic impedance layer L1-L10 ... Inductors P1, P2, P21, P22, P31-P34 ... Parallel arm Resonator S1 to S3, S21 to S24, S31 to S34 ... Series arm resonator

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  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)

Abstract

La présente invention concerne un résonateur acoustique en volume à film qui utilise un film mince piézoélectrique à base de nitrure d'aluminium contenant du Sc, et qui peut à la fois obtenir une bande passante fractionnaire satisfaisante et améliorer la caractéristique fréquence-température. Ledit résonateur acoustique en volume à film (1) comprend : un film mince piézoélectrique (6) qui comporte un film de nitrure d'aluminium contenant du Sc, le Sc ayant une concentration comprise entre 0,5 et 24 % atm et la somme du nombre d'atomes de scandium et du nombre d'atomes d'aluminium représentant 100 % atm ; des première et seconde électrodes (5, 7) disposées en regard du film mince piézoélectrique (6) ; ainsi qu'un substrat (2) prévu pour porter une partie oscillante piézoélectrique qui comporte ledit film mince piézoélectrique (6) et les première et seconde électrodes (5, 7).
PCT/JP2012/076836 2011-10-31 2012-10-17 Résonateur acoustique en volume à film, dispositif de filtrage et duplexeur WO2013065488A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2011-238942 2011-10-31
JP2011238942 2011-10-31
JP2012-034310 2012-02-20
JP2012034310 2012-02-20

Publications (1)

Publication Number Publication Date
WO2013065488A1 true WO2013065488A1 (fr) 2013-05-10

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9083302B2 (en) 2011-02-28 2015-07-14 Avago Technologies General Ip (Singapore) Pte. Ltd. Stacked bulk acoustic resonator comprising a bridge and an acoustic reflector along a perimeter of the resonator
US9136818B2 (en) 2011-02-28 2015-09-15 Avago Technologies General Ip (Singapore) Pte. Ltd. Stacked acoustic resonator comprising a bridge
US9148117B2 (en) 2011-02-28 2015-09-29 Avago Technologies General Ip (Singapore) Pte. Ltd. Coupled resonator filter comprising a bridge and frame elements
US9154112B2 (en) 2011-02-28 2015-10-06 Avago Technologies General Ip (Singapore) Pte. Ltd. Coupled resonator filter comprising a bridge
US9246473B2 (en) 2011-03-29 2016-01-26 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising collar, frame and perimeter distributed bragg reflector
US9401692B2 (en) 2012-10-29 2016-07-26 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator having collar structure
US9425764B2 (en) 2012-10-25 2016-08-23 Avago Technologies General Ip (Singapore) Pte. Ltd. Accoustic resonator having composite electrodes with integrated lateral features
US9444426B2 (en) 2012-10-25 2016-09-13 Avago Technologies General Ip (Singapore) Pte. Ltd. Accoustic resonator having integrated lateral feature and temperature compensation feature
US9490771B2 (en) 2012-10-29 2016-11-08 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising collar and frame
US9490770B2 (en) 2011-03-29 2016-11-08 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising temperature compensating layer and perimeter distributed bragg reflector
US9490418B2 (en) 2011-03-29 2016-11-08 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising collar and acoustic reflector with temperature compensating layer
JP2019068295A (ja) * 2017-10-02 2019-04-25 株式会社村田製作所 フィルタ
CN110729977A (zh) * 2018-07-17 2020-01-24 太阳诱电株式会社 通信模块

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004064786A (ja) * 2002-07-30 2004-02-26 Agilent Technol Inc シード層を有する共振器
JP2005223808A (ja) * 2004-02-09 2005-08-18 Murata Mfg Co Ltd 圧電薄膜フィルタ、分波器、通信機
JP2005260915A (ja) * 2004-02-09 2005-09-22 Murata Mfg Co Ltd 分波器、通信機
WO2006008940A1 (fr) * 2004-07-20 2006-01-26 Murata Manufacturing Co., Ltd. Filtre piézoélectrique
WO2006137275A1 (fr) * 2005-06-20 2006-12-28 Murata Manufacturing Co., Ltd. Filtre à film mince piézoélectrique
JP2008172713A (ja) * 2007-01-15 2008-07-24 Hitachi Media Electoronics Co Ltd 圧電薄膜共振器および圧電薄膜共振器フィルタおよびその製造方法
JP2008311873A (ja) * 2007-06-13 2008-12-25 Fujitsu Media Device Kk フィルタ
JP2009010926A (ja) * 2007-05-31 2009-01-15 National Institute Of Advanced Industrial & Technology 圧電体薄膜、圧電体およびそれらの製造方法、ならびに当該圧電体薄膜を用いた圧電体共振子、アクチュエータ素子および物理センサー
JP2009149953A (ja) * 2007-12-21 2009-07-09 National Institute Of Advanced Industrial & Technology 窒化物半導体の製造方法および窒化物半導体デバイス
JP2009290368A (ja) * 2008-05-27 2009-12-10 Panasonic Electric Works Co Ltd Ｂａｗ共振装置の製造方法
WO2010061496A1 (fr) * 2008-11-25 2010-06-03 株式会社村田製作所 Dispositif de filtre d’onde élastique
JP2011015148A (ja) * 2009-07-01 2011-01-20 National Institute Of Advanced Industrial Science & Technology 圧電体薄膜の製造方法および当該製造方法により製造される圧電体薄膜

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004064786A (ja) * 2002-07-30 2004-02-26 Agilent Technol Inc シード層を有する共振器
JP2005223808A (ja) * 2004-02-09 2005-08-18 Murata Mfg Co Ltd 圧電薄膜フィルタ、分波器、通信機
JP2005260915A (ja) * 2004-02-09 2005-09-22 Murata Mfg Co Ltd 分波器、通信機
WO2006008940A1 (fr) * 2004-07-20 2006-01-26 Murata Manufacturing Co., Ltd. Filtre piézoélectrique
WO2006137275A1 (fr) * 2005-06-20 2006-12-28 Murata Manufacturing Co., Ltd. Filtre à film mince piézoélectrique
JP2008172713A (ja) * 2007-01-15 2008-07-24 Hitachi Media Electoronics Co Ltd 圧電薄膜共振器および圧電薄膜共振器フィルタおよびその製造方法
JP2009010926A (ja) * 2007-05-31 2009-01-15 National Institute Of Advanced Industrial & Technology 圧電体薄膜、圧電体およびそれらの製造方法、ならびに当該圧電体薄膜を用いた圧電体共振子、アクチュエータ素子および物理センサー
JP2008311873A (ja) * 2007-06-13 2008-12-25 Fujitsu Media Device Kk フィルタ
JP2009149953A (ja) * 2007-12-21 2009-07-09 National Institute Of Advanced Industrial & Technology 窒化物半導体の製造方法および窒化物半導体デバイス
JP2009290368A (ja) * 2008-05-27 2009-12-10 Panasonic Electric Works Co Ltd Ｂａｗ共振装置の製造方法
WO2010061496A1 (fr) * 2008-11-25 2010-06-03 株式会社村田製作所 Dispositif de filtre d’onde élastique
JP2011015148A (ja) * 2009-07-01 2011-01-20 National Institute Of Advanced Industrial Science & Technology 圧電体薄膜の製造方法および当該製造方法により製造される圧電体薄膜

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9083302B2 (en) 2011-02-28 2015-07-14 Avago Technologies General Ip (Singapore) Pte. Ltd. Stacked bulk acoustic resonator comprising a bridge and an acoustic reflector along a perimeter of the resonator
US9136818B2 (en) 2011-02-28 2015-09-15 Avago Technologies General Ip (Singapore) Pte. Ltd. Stacked acoustic resonator comprising a bridge
US9148117B2 (en) 2011-02-28 2015-09-29 Avago Technologies General Ip (Singapore) Pte. Ltd. Coupled resonator filter comprising a bridge and frame elements
US9154112B2 (en) 2011-02-28 2015-10-06 Avago Technologies General Ip (Singapore) Pte. Ltd. Coupled resonator filter comprising a bridge
US9490770B2 (en) 2011-03-29 2016-11-08 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising temperature compensating layer and perimeter distributed bragg reflector
US9246473B2 (en) 2011-03-29 2016-01-26 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising collar, frame and perimeter distributed bragg reflector
US9490418B2 (en) 2011-03-29 2016-11-08 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising collar and acoustic reflector with temperature compensating layer
US9425764B2 (en) 2012-10-25 2016-08-23 Avago Technologies General Ip (Singapore) Pte. Ltd. Accoustic resonator having composite electrodes with integrated lateral features
US9444426B2 (en) 2012-10-25 2016-09-13 Avago Technologies General Ip (Singapore) Pte. Ltd. Accoustic resonator having integrated lateral feature and temperature compensation feature
US9401692B2 (en) 2012-10-29 2016-07-26 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator having collar structure
US9490771B2 (en) 2012-10-29 2016-11-08 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator comprising collar and frame
JP2019068295A (ja) * 2017-10-02 2019-04-25 株式会社村田製作所 フィルタ
US10742194B2 (en) 2017-10-02 2020-08-11 Murata Manufacturing Co., Ltd. Filter
CN110729977A (zh) * 2018-07-17 2020-01-24 太阳诱电株式会社 通信模块
CN110729977B (zh) * 2018-07-17 2024-01-09 太阳诱电株式会社 通信模块

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