WO2010095640A1 - 薄膜圧電共振器およびそれを用いた薄膜圧電フィルタ - Google Patents
薄膜圧電共振器およびそれを用いた薄膜圧電フィルタ Download PDFInfo
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- WO2010095640A1 WO2010095640A1 PCT/JP2010/052336 JP2010052336W WO2010095640A1 WO 2010095640 A1 WO2010095640 A1 WO 2010095640A1 JP 2010052336 W JP2010052336 W JP 2010052336W WO 2010095640 A1 WO2010095640 A1 WO 2010095640A1
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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
- H03H9/15—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
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
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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
- H03H9/02—Details
- H03H9/02007—Details of bulk acoustic wave devices
- H03H9/02086—Means for compensation or elimination of undesirable effects
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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
- H03H9/02—Details
- H03H9/02007—Details of bulk acoustic wave devices
- H03H9/02086—Means for compensation or elimination of undesirable effects
- H03H9/02133—Means for compensation or elimination of undesirable effects of stress
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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
- H03H9/02—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
- H03H9/174—Membranes
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- H—ELECTRICITY
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- 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
Definitions
- the present invention relates to a thin film piezoelectric resonator and a thin film piezoelectric filter using the same, and particularly to a thin film piezoelectric resonator having a high quality factor (Q value) and suppressing noise generation, and a thin film piezoelectric filter using the same.
- Q value quality factor
- the thin film piezoelectric resonator and the thin film piezoelectric filter are used to constitute a communication device such as a cellular phone.
- the RF circuit part of a cellular phone is always required to be downsized. Recently, it has been demanded to give various functions to cellular telephones, and it is preferable to incorporate as many components as possible in order to realize such functions. On the other hand, since the size of the cellular phone is limited, the demand for reducing the exclusive area (mounting area) and height of the device is severe. Accordingly, components constituting the RF circuit section are also required to have a small exclusive area and a low height.
- a thin film piezoelectric filter using a thin film piezoelectric resonator that is small and can be reduced in weight is used as a band pass filter used in an RF circuit.
- the thin film piezoelectric filter as described above forms a piezoelectric thin film such as aluminum nitride (AlN) or zinc oxide (ZnO) so as to be sandwiched between upper and lower electrodes on a semiconductor substrate, and elastic wave energy leaks into the semiconductor substrate.
- AlN aluminum nitride
- ZnO zinc oxide
- an RF filter using a thin film bulk acoustic resonator (FBAR) having a cavity immediately below it is provided.
- FBAR thin film bulk acoustic resonator
- FIGS. 17A to 17C show an example of a conventional thin film piezoelectric resonator.
- 17A is a schematic plan view
- FIG. 17B is an XX cross-sectional view of FIG. 17A
- FIG. 17C is a YY cross-sectional view of FIG. 17A.
- the thin film piezoelectric resonator of FIGS. 17A to 17C has a piezoelectric substrate in the form of a substrate 6 on which an air gap 4 is formed and a peripheral portion supported by an edge on the upper surface of the substrate 6 adjacent to the air gap 4 and suspended. And a resonator stack 12.
- the piezoelectric resonator stack 12 includes a piezoelectric thin film 2 and a lower electrode 8 and an upper electrode 10 formed so as to sandwich the piezoelectric thin film.
- the layers of the piezoelectric thin film, the lower electrode, and the upper electrode may be referred to as a piezoelectric layer (piezoelectric layer), a lower electrode layer, and an upper electrode layer, respectively.
- a piezoelectric resonator stack 12 composed of a laminate of the piezoelectric layer 2, the lower electrode layer 8 and the upper electrode layer 10 is suspended at the periphery thereof, and the main portion in the central portion (portion corresponding to the air gap 4). Both surfaces are in contact with air or other ambient gas or vacuum.
- the piezoelectric resonator stack 12 forms an acoustic resonator having a high Q value.
- the AC signal applied to the lower electrode layer 8 and the upper electrode layer 10 has a frequency equal to a value obtained by dividing the speed of sound in the piezoelectric resonator stack 12 by twice the weighted thickness of the stack 12.
- the piezoelectric resonator stack 12 resonates. Since the sound velocity in the layers constituting the stack 12 differs depending on the material constituting each layer, the resonance frequency of the piezoelectric resonator stack 12 is not the physical thickness, but the piezoelectric layer 2, the lower electrode layer 8, and the upper electrode layer 10. It is determined by the weighted thickness considering the sound speed and the physical thickness.
- the vibration region in which the resonance occurs in the piezoelectric resonator stack 12 is a region where the upper electrode 10 and the lower electrode 8 overlap each other as viewed in the thickness direction.
- Patent Document 1 discloses a technique for preventing characteristic deterioration due to the unnecessary transverse acoustic mode (spurious vibration) as described above.
- 18A and 18B are cross-sectional views of the thin film piezoelectric resonator described in Patent Document 1.
- FIG. Here, the generation of noise due to the transverse acoustic mode is suppressed by providing a frame-like zone 60 such as a frame at the end (peripheral) of the upper electrode.
- 18A shows a structure applied when the piezoelectric layer is a type 1 piezoelectric material having a low-frequency cutoff dispersion curve such as ZnO
- FIG. 18B shows a high-frequency cutoff dispersion curve such as AlN. This is a structure used in the case of a type 2 piezoelectric material.
- a quality factor Q value
- kt 2 electromechanical coupling factor
- FIG. 19A and 19B show an example of an impedance characteristic diagram and an example of a Smith chart of a thin film piezoelectric resonator, respectively.
- the impedance (Rs) and Q value (Qs) at the resonance frequency (fs) and the impedance (Rp) and Q value (Qp) at the antiresonance frequency (fp) are the main characteristic factors.
- Rs is decreased and Rp is increased.
- the left end of the chart is the resonance frequency (fs)
- the right end of the chart is the antiresonance frequency (fp).
- the characteristics of the thin film piezoelectric resonator are better as it comes into contact with the outer circumference of the chart.
- Rs is largely due to the electrical resistance of the electrode
- Rp is largely due to thermal loss of elastic energy and energy loss due to leakage of elastic waves outside the vibration region.
- Patent Document 2 discloses a thin film piezoelectric resonator that suppresses the occurrence of spurious vibrations and has an excellent Q value by introducing a structure in which the thickness of the upper electrode is increased in the frame shape of the outer peripheral portion of the vibration region using an AlN thin film. Is shown to be obtained.
- Patent Document 3 includes an annulus positioned on the surface of one of an upper electrode and a lower electrode, a region within the annulus has a first acoustic impedance, and the annulus has a second acoustic impedance.
- the outer region of the annulus has a third acoustic impedance, the second acoustic impedance being shown as a thin film piezoelectric resonator greater than the first and third acoustic impedances, thereby It has been shown that a thin film piezoelectric resonator having an excellent Q value can be obtained.
- the piezoelectric resonator stack composed of the piezoelectric layer, the lower electrode, and the upper electrode is formed on the gap, it is structurally fragile and easily causes mechanical damage in the manufacturing process. Therefore, in order to prevent damage to the thin film piezoelectric resonator, as described in Patent Document 4 and Patent Document 5, the gap is covered with the lower electrode, that is, the lower electrode is in contact with the substrate. It has been proposed.
- Patent Document 1 Although the technique described in Patent Document 1 can suppress the occurrence of spurious vibrations, as described in Patent Document 3, the Q value of the thin film piezoelectric resonator is lowered, which is not preferable.
- Patent Document 2 can improve the Q value of the thin film piezoelectric resonator.
- the resonance frequency of the primary thickness longitudinal vibration is different between the outer peripheral portion and the central portion.
- a peak due to the primary thickness longitudinal vibration of the outer peripheral portion of the vibration region which is not originally required occurs and the filter characteristics are likely to be deteriorated.
- kt 2 becomes small.
- Patent Document 3 can improve the Q value of a thin film piezoelectric resonator.
- the acoustic impedance of the outer peripheral portion (annular zone) of the vibration region is made larger than that of the central portion and the buffer region of the vibration region, that is, the thickness of the outer peripheral portion of the vibration region is increased as in Patent Document 2. It is thick and has the same problems as in Patent Document 2. Furthermore, it can be seen from the example of Patent Document 3 that the spurious response due to another vibration mode is large at a frequency lower than the resonance frequency (fs) in the primary thickness vibration mode.
- the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a thin film piezoelectric resonator having a high Q value and a high kt 2 while suppressing the occurrence of spurious noise. Another object of the present invention is to provide a thin film piezoelectric filter using the thin film piezoelectric resonator.
- thin film piezoelectric filters are required to suppress spurious characteristics appearing in the passband and to realize low insertion loss.
- the thin film piezoelectric resonator is required to suppress the transverse acoustic mode, which is an unnecessary vibration, and to have a high quality factor Q value, and the effective electrical factor, which is the main factor that determines the pass bandwidth of the thin film piezoelectric filter. It is required to increase the mechanical coupling coefficient (effective kt 2 ). In order to improve the manufacturing yield, a robust resonator structure that does not break during the manufacturing process is required.
- the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a thin-film piezoelectric resonator that has a large effective kt 2 and a high Q value, and is robust and less damaged.
- a piezoelectric resonator stack having a substrate, a piezoelectric layer on the substrate, and an upper electrode and a lower electrode formed to face each other with the piezoelectric layer interposed therebetween, and the substrate and the piezoelectric resonator stack;
- a thin film piezoelectric resonator comprising a gap or an acoustic reflection layer formed between The piezoelectric resonator stack has a vibration region in which the upper electrode and the lower electrode overlap each other when viewed in the thickness direction of the piezoelectric resonator stack,
- the vibration region includes a first vibration region, a second vibration region, and a third vibration region, When viewed in the thickness direction of the piezoelectric resonator stack, the first vibration region is present at the outermost side, the third vibration region is present at the innermost side and is not in contact with the first vibration region, and Two vibration regions are interposed between the first vibration region and the third vibration region,
- the piezoelectric resonator stack has different thicknesses in the first vibration region, the second vibration region, and the third vibration region.
- the piezoelectric resonator stack has a frame layer additionally formed on the upper electrode in an outer peripheral portion of the vibration region.
- the thickness of the frame layer decreases from an outer portion in contact with the first vibration region toward an inner portion in contact with the third vibration region in the second vibration region.
- the frame layer has a slope-shaped upper surface in the second vibration region, and an angle of the slope-shaped upper surface with respect to the upper surface of the substrate is 60 ° or less.
- the frame layer is made of a material having a Young's modulus of 1.0 ⁇ 10 11 N / m 2 or more.
- the Z f and the Z u are 0.5 Z u ⁇
- the relationship of Z f ⁇ 2Z u is satisfied.
- the thickness of the upper electrode or the lower electrode decreases from an outer portion in contact with the first vibration region toward an inner portion in contact with the third vibration region in the second vibration region.
- the upper electrode or the lower electrode has a slope-shaped upper surface in the second vibration region, and an angle of the slope-shaped upper surface with respect to the upper surface of the substrate is 60 ° or less.
- the upper electrode or the lower electrode is made of a material having a Young's modulus of 1.0 ⁇ 10 11 N / m 2 or more.
- the first vibration region has a width of 3 ⁇ m or less.
- the piezoelectric layer is made of aluminum nitride.
- the vibration region is present inside the gap or the outer peripheral edge of the acoustic reflection layer when viewed in the thickness direction of the piezoelectric resonator stack.
- the piezoelectric resonator stack is positioned between the support region located outside the vibration region and between the vibration region and the support region when viewed in the thickness direction of the piezoelectric resonator stack.
- a buffer region and is in contact with the substrate in the support region.
- the piezoelectric resonator stack has a frame layer additionally formed on the upper electrode at an outer peripheral portion of the vibration region, and the frame layer includes the first vibration region.
- the thickness is the same over the buffer region and the support region. According to this, a thin film piezoelectric resonator having a higher Q value and a larger kt 2 and a smaller resistance value at the resonance frequency can be provided.
- the lower electrode has a support portion extending along a boundary between the support region and the buffer region in the support region, and the width w1 of the support portion and the vibration region
- the thickness t of the piezoelectric resonator stack satisfies the relationship of 2.17 ⁇ w1 / t ⁇ 10, and the width w2 of the buffer region and the thickness t of the piezoelectric resonator stack in the vibration region are 0.25 ⁇ w2 / t.
- the relation of ⁇ 2 is satisfied. According to this, it is possible to realize a thin film piezoelectric resonator having a large effective kt 2 and a high Q value and being extremely robust.
- the support portion of the lower electrode is formed so as not to overlap both the upper electrode and the external connection conductor connected to the upper electrode when viewed in the thickness direction of the piezoelectric resonator stack. ing.
- the vibration region has an elliptical shape.
- the major axis diameter a and the minor axis diameter b of the ellipse preferably satisfy the relationship 1 ⁇ a / b ⁇ 1.9. According to this, it is possible to realize a thin film piezoelectric resonator that can suppress generation of unnecessary vibration modes and suppress ripples generated in the pass band of the thin film piezoelectric filter.
- the piezoelectric resonator stack is made of at least one material selected from the group consisting of AlN, AlON, Si 3 N 4 and SiAlON on the upper electrode and / or below the lower electrode. And having a dielectric layer. According to this, it is possible to protect the upper electrode and / or the lower electrode, it is possible to realize a very robust thin film piezoelectric resonator having a large effective kt 2 and a high Q value, and under the lower electrode. When the dielectric layer is formed, the dielectric layer functions as a support layer of the piezoelectric resonator stack and the support force is increased, so that a more robust thin film piezoelectric resonator can be provided.
- a thin film piezoelectric filter using the thin film piezoelectric resonator is a ladder type or lattice.
- a ladder type filter or lattice type filter connected to a mold, wherein the thin film piezoelectric resonator is used only for the parallel thin film piezoelectric resonator.
- a thin film piezoelectric resonator having a high Q value and a large kt 2 while suppressing generation of noise based on spurious due to another vibration mode or unnecessary thickness longitudinal vibration is provided. can do. Furthermore, it is possible to provide a thin film piezoelectric filter that can extremely reduce noise in the passband and reduce insertion loss in the passband.
- the thin film piezoelectric resonator of the present invention it is possible to realize a very robust thin film piezoelectric resonator having a large effective kt 2 and a high Q value.
- FIG. 1 is a schematic plan view showing an embodiment of a thin film piezoelectric resonator of the present invention. It is XX sectional drawing of FIG. 1A.
- FIG. 1B is a YY cross-sectional view of FIG. 1A. It is a typical top view showing a vibration field, a buffer field, and a support field of one embodiment of a thin film piezoelectric resonator of the present invention.
- It is a schematic diagram which shows the cross-sectional shape of the frame layer of one Embodiment of the thin film piezoelectric resonator of this invention. It is a schematic diagram which shows the cross-sectional shape of the frame layer of one Embodiment of the thin film piezoelectric resonator of this invention.
- FIG. 6B is a YY sectional view showing the embodiment of FIG. 6A. It is XX sectional drawing which shows other one Embodiment of the thin film piezoelectric resonator of this invention.
- FIG. 7B is a YY sectional view showing the embodiment of FIG. 7A. It is XX sectional drawing which shows other one Embodiment of the thin film piezoelectric resonator of this invention. It is a YY sectional view showing the embodiment of FIG. 8A. It is XX sectional drawing which shows other one Embodiment of the thin film piezoelectric resonator of this invention.
- FIG. 9B is a YY sectional view showing the embodiment of FIG. 9A.
- FIG. 6 is a schematic plan view showing another embodiment of the thin film piezoelectric resonator of the present invention.
- FIG. 10B is a sectional view taken along line XX in FIG. 10A.
- FIG. 10B is a YY sectional view of FIG.
- FIG. 10A It is a figure which shows the circuit of the ladder type filter which is one Embodiment of the filter using the thin film piezoelectric resonator of this invention. It is a figure which shows the circuit of the lattice type filter which is one Embodiment of the filter using the thin film piezoelectric resonator of this invention. It is an impedance characteristic view of the thin film piezoelectric resonator of the present invention obtained in Example 1. 1 is a Smith chart of a thin film piezoelectric resonator of the present invention obtained in Example 1.
- FIG. 6 is an impedance characteristic diagram of the thin film piezoelectric resonator of the present invention obtained in Comparative Example 1.
- FIG. 6 is a Smith chart of the thin film piezoelectric resonator of the present invention obtained in Comparative Example 1.
- FIG. 6 is an impedance characteristic diagram of a thin film piezoelectric resonator of the present invention obtained in Comparative Example 5.
- FIG. 6 is a Smith chart of a thin film piezoelectric resonator of the present invention obtained in Comparative Example 5.
- FIG. It is a figure which shows the passage characteristic of the thin film piezoelectric filter obtained in Examples 29 and 30 and Comparative Example 6. It is a typical top view which shows an example of the conventional thin film piezoelectric resonator. It is XX sectional drawing of FIG. 17A.
- FIG. 17B is a YY sectional view of FIG. 17A.
- FIG. 20A is a schematic plan view showing an embodiment of a thin film piezoelectric resonator of the present invention. It is XX sectional drawing of FIG. 20A. FIG. 20B is a YY sectional view of FIG. 20A.
- FIG. 20A is a schematic plan view showing an embodiment of a thin film piezoelectric resonator of the present invention. It is XX sectional drawing of FIG. 20A.
- FIG. 20B is a YY sectional view of FIG. 20A.
- FIG. 2 is a schematic plan view showing a vibration region, a buffer region, a support region, and a lower electrode support portion in the embodiment of FIG. 1.
- It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention. It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention. It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention. It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention. It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention. It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention.
- FIG. 12 It is a typical sectional view showing one embodiment of a thin film piezoelectric resonator of the present invention. It is a figure which shows Q value of the thin film piezoelectric resonator obtained in Examples 36-39 and Comparative Examples 12-15. It is a figure which shows Q value and effective kt 2 of the thin film piezoelectric resonator obtained in Examples 40 to 42 and Comparative Examples 12 and 16 to 18.
- FIG. 1A is a schematic plan view showing an embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 1B is a cross-sectional view taken along the line XX of FIG. 1A
- FIG. 1C is a cross-sectional view taken along the line YY of FIG. .
- the thin film piezoelectric resonator includes a substrate 6 and a piezoelectric resonator stack 12.
- the substrate 6 has an insulating layer 7 in the upper layer portion. That is, the substrate 6 includes the insulating layer 7.
- a gap (air gap), that is, a vibration space 4 is formed between the substrate 6 and the piezoelectric resonator stack 12.
- the piezoelectric resonator stack 12 is on the substrate 6, that is, on the insulating layer 7, the piezoelectric thin film (piezoelectric layer) 2, the lower electrode 8 formed so as to face each other in the film thickness direction with the piezoelectric thin film interposed therebetween, and And an upper electrode 10.
- the outer shape of the portion sandwiched between the lower electrode 8 and the upper electrode 10 of the piezoelectric thin film 2 (the shape when viewed in the thickness direction of the piezoelectric resonator stack 12) is an ellipse.
- the connection conductor (external connection conductor) 14 which is a conductive thin film formed to connect the upper electrode 10 and the lower electrode 8 to an external circuit is not included in these shapes. Further, the boundary between the connection conductor 14 and the upper electrode 10 or the lower electrode 8 is obtained by extending the outline of the upper electrode 10 or the lower electrode 8.
- the piezoelectric resonator stack 12 has a vibration region 40 in which the upper electrode 10 and the lower electrode 8 overlap each other when viewed in the thickness direction of the piezoelectric resonator stack.
- the piezoelectric resonator stack 12 further includes a support region 48 positioned outside the vibration region 40 and a buffer region 46 positioned between the vibration region 40 and the support region 48 when viewed in the thickness direction of the piezoelectric resonator stack.
- Have The piezoelectric resonator stack 12 is in contact with the substrate 6 in the support region 48.
- the lower electrode 8 has a support portion 18 ′ extending along the boundary between the support region 48 and the buffer region 46 in the support region 48. As shown in the drawing, the support portion 18 ′ can be configured not to overlap the upper electrode 10 and the external connection conductor 14 connected thereto when viewed in the thickness direction of the piezoelectric resonator stack 12.
- FIG. 2 is a schematic plan view showing the vibration region 40, the buffer region 46, and the support region 48 of the present embodiment.
- the vibration area 40 includes a first vibration area 41, a second vibration area 42, and a third vibration area 43.
- the first vibration region 41 is present on the outermost side and is in contact with the buffer region 46
- the third vibration region 43 is present on the innermost side
- the second vibration region 42 is interposed between the first vibration region 41 and the third vibration region 43.
- the width of the first vibration region 41 is Wt
- the width of the second vibration region 42 is Ws.
- the resonance frequency of the primary thickness longitudinal vibration of the vibration region 40 is f 1 in the first vibration region 41 and f 2 in the third vibration region 43, where f 1 and f 2 are f 1 ⁇ f 2 .
- the relationship is satisfied, and in the second vibration region 42, the value increases from f 1 to f 2 from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43.
- Such a relationship of the primary thickness longitudinal vibration frequency is such that the thickness of the piezoelectric resonator stack 12 and / or the material of the constituent layers are different from each other in the first vibration region 41, the second vibration region 42, and the third vibration region 43.
- This can be realized.
- a technique for that for example, a method of changing the thickness and / or constituent material of any of the lower electrode 8, the piezoelectric layer 2 and the upper electrode 10 constituting the vibration region 40 according to the location of the vibration region 40, Or the method of adding the layer which comprises a piezoelectric resonator stack further is mentioned.
- the main feature of the present invention is realized by forming the frame layer 16 as an additional layer on the upper electrode 10.
- the frame layer 16 is formed on the upper electrode 10 at the outer peripheral portion of the vibration region 40, and the outer portion in contact with the buffer region 46 constitutes the first vibration region 41 and the inner portion constitutes the second vibration region 42. is doing.
- the frame layer 16 has a thickness T in the first vibration region 41.
- the cross-sectional shape of the frame layer 16 (the shape of the vertical cross-section passing through the center of the vibration region 40) in the inner part constituting the second vibration region 42 is a slope shape. That is, as shown in FIG. 1B and FIG.
- the frame layer 16 gradually increases in thickness from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43 in the second vibration region 42. is decreasing.
- the upper surface of the frame layer 16 is inclined with respect to the upper surface of the substrate 6 to form a slope-shaped upper surface.
- FIGS. 1A to 1C are schematic views showing the cross-sectional shape of the frame layer 16.
- the frame layer 16 has a linear slope in the second vibration region 42 as shown in FIG. 3A.
- the angle ⁇ of the slope (that is, the angle formed by the sloped upper surface of the frame layer 16 with respect to the upper surface of the substrate 6 in the second vibration region 42) is preferably 1 degree or more and 60 degrees or less. The reason is that if the angle ⁇ is less than 1 degree and is too small, the width Ws of the second vibration region 42 becomes too large, which is disadvantageous for downsizing of the resonator and the manufacturing difficulty tends to increase. This is because if it exceeds 60 degrees and is too large, the width Ws of the second vibration region 42 becomes too small and it is difficult to obtain good resonator characteristics targeted by the present invention.
- the vertical cross-sectional shape in the second vibration region 42 of the frame layer 16 in the present invention is not limited to the above.
- the longitudinal cross-sectional shape may be, for example, a curved slope shape as shown in FIG. 3B, or may be a step-like (polygonal) slope shape as shown in FIG. 3C. Other shapes may be used.
- the angle ⁇ is assumed to be an angle obtained by linear approximation.
- the vertical cross-sectional shape of the upper electrode 10 or the upper electrode 8 is changed as described later without providing the frame layer 16. Similarly, it may be sloped.
- Resonating the primary thickness longitudinal vibration in the second vibration region 42 by making the longitudinal cross-sectional shape of the upper electrode 10, the lower electrode 8, or the additional layer of the frame layer 16 constituting the second vibration region 42 into a slope shape.
- the frequency gradually changes (increases) while taking a value between f 1 and f 2 from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43.
- the resonance frequency of the primary thickness longitudinal vibration in the second vibration region 42 is changed from the outer portion in contact with the first vibration region 41 to the third vibration region 43 according to the slope angle ⁇ . It increases monotonously toward the inner part that touches.
- the resonance frequency of the primary thickness longitudinal vibration in the horizontal step portion has a constant value.
- the piezoelectric resonator stack 12 is configured as described above, and in particular, the resonance frequency of the primary thickness longitudinal vibration in the second vibration region 42 is directed from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43.
- the resonance frequency of the primary thickness longitudinal vibration in the second vibration region 42 is directed from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43.
- the substrate 6 is made of a silicon substrate, a gallium arsenide substrate, a glass substrate, or the like.
- the piezoelectric thin film (piezoelectric layer) 2 is made of a piezoelectric material that can be manufactured as a thin film such as zinc oxide (ZnO) or aluminum nitride (AlN), and preferably aluminum nitride exhibiting a high-frequency cutoff type dispersion curve. Consists of.
- the lower electrode 8 and the upper electrode 10 are made of a metal material that can be manufactured as a thin film such as molybdenum, tungsten, ruthenium, platinum, or aluminum.
- the thin film piezoelectric resonator of the embodiment of FIGS. 1A to 1C can be manufactured as follows, for example.
- An insulating layer 7 is formed on a semiconductor substrate 6 such as a silicon substrate by a film formation technique such as sputtering or CVD.
- a film formation technique such as sputtering or CVD.
- the insulating layer 7 can be formed by thermal oxidation.
- a sacrificial layer that is easily dissolved by an etching solution is formed by a film formation method such as sputtering or vapor deposition, and the vibration space 4 should be formed using a patterning technique such as wet etching, RIE, or lift-off. Patterning is performed so that the sacrificial layer remains at the position.
- the sacrificial layer metals such as germanium (Ge), aluminum (Al), titanium (Ti), magnesium (Mg), or oxides thereof are suitable.
- the lower electrode 8, the piezoelectric layer 2, and the upper electrode 10 are formed by a film forming method such as sputtering or vapor deposition, and each layer is patterned using a patterning technique such as wet etching, RIE, or lift-off.
- the frame layer 16 is formed and patterned. At this time, the frame layer 16 is formed on the outer peripheral portion of the vibration region 40, and the upper surface (also referred to as end surface) on the center side (inside) of the vibration region 40 is processed to have a slope shape.
- a second vibration region 42 is formed. Further, a region where the thickness of the frame layer 16 outside the second vibration region 42 is uniform is defined as a first vibration region 41.
- patterning by a lift-off method or an RIE method is preferable.
- FIG. 4A to 4C are schematic views showing a method for manufacturing the frame layer 16 having the slope-shaped end face in the present embodiment by the lift-off method.
- a resist film 70 having a reverse tapered slope as shown in FIG. 4A is formed by controlling the exposure conditions mainly using a negative resist.
- the frame layer 16 is formed (the state shown in FIG. 4B), and the resist film 70 is peeled off using a stripping solution, thereby forming the frame layer 16 having a sloped end surface as shown in FIG. 4C. it can.
- FIGS. 5A to 5D are schematic views showing a method of manufacturing the frame layer 16 having the slope-shaped end face in the present embodiment by the RIE method.
- the exposure and development conditions are selected so that the end portion of the resist film 70 has a slope shape, and the end surface has a slope shape.
- a resist film 70 is formed.
- the edge of the resist film 70 is gradually etched and retracted as the frame layer 16 is etched.
- the frame layer 16 having an end surface as shown in FIG. 5D having a slope shape can be formed.
- the frame layer 16 is patterned by a patterning technique such as the RIE method in accordance with the outer peripheral shape of the upper electrode 10, thereby forming the frame layer 16 in which the end surface (outer end surface) of the peripheral portion is not a slope shape.
- the through hole 30 reaching from the upper surface of the upper electrode 10 to the sacrificial layer is formed using the patterning technique, and then the sacrificial layer is etched and removed with an etching solution supplied through the through hole 30.
- an etchant that can etch the insulating layer 7 and etching the insulating layer 7, the insulating layer 7 can be etched in the same pattern as the sacrificial layer.
- An oscillating space (air gap or void) 4 is formed in the sacrificial layer and the insulating layer 7 thus removed.
- the lower electrode 8 is set larger than the sacrificial layer by a predetermined shape
- the upper electrode 10 is set smaller than the sacrificial layer by a predetermined shape, so that a buffer region 46 is formed on the air gap 4 and further a support region on the insulating layer 7 of the substrate 6. 48 is formed.
- the vibration region 40 exists inside the outer peripheral edge of the gap 4 when viewed in the thickness direction of the piezoelectric resonator stack 12.
- FIG. 6A is an XX sectional view showing another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 6B is a YY sectional view showing the embodiment of FIG. 6A.
- This embodiment differs from the embodiment described with reference to FIGS. 1A to 1C and the like only in the method of forming the first vibration region 41, the second vibration region 42, and the third vibration region 43. That is, in the present embodiment, the frame layer 16 is not provided, and the first vibration region 41, the second vibration region 42, and the third vibration region in the vibration region 40 by changing the thickness of the upper electrode 10 depending on the location. 43 is formed.
- the thickness of the upper electrode 10 in the first vibration region 41 is larger than the thickness of the upper electrode 10 in the third vibration region 43 by T.
- the thickness of the upper electrode 10 decreases from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43.
- the upper surface of the upper electrode 10 is inclined with respect to the upper surface of the substrate 6 in the second vibration region 42 to be a sloped upper surface.
- the thin film piezoelectric resonator according to the embodiment shown in FIGS. 6A and 6B can be manufactured as follows, for example.
- the formation method from the insulating layer to the piezoelectric layer is the same as the embodiment described with reference to FIGS. 1A to 1C and others.
- the upper electrode 10 is formed by a film forming technique such as sputtering, vapor deposition or CVD, a predetermined amount of the area other than the first vibration area 41 and the second vibration area 42 is etched away by an etching technique such as RIE. To do.
- the processing is performed by the above-described RIE method so that the cross-sectional shape of the region serving as the second vibration region becomes a slope shape.
- the outer shape of the upper electrode 10 is set to a predetermined shape by patterning using a patterning technique such as wet etching and RIE. Thereafter, as in the embodiment described with reference to FIGS. 1A to 1C, etc., a through hole 30 reaching from the upper surface of the upper electrode to the sacrificial layer is formed, and then the sacrificial layer and a part of the insulating layer are removed with an etching solution. Thus, the vibration space 4 is formed.
- a patterning technique such as wet etching and RIE.
- FIG. 7A is an XX sectional view showing another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 7B is a YY sectional view showing the embodiment of FIG. 7A.
- This embodiment differs from the embodiment described with reference to FIGS. 1A to 1C and the like only in the method of forming the first vibration region 41, the second vibration region 42, and the third vibration region 43. That is, in the present embodiment, the frame layer 16 is not provided, and the first vibration region 41, the second vibration region 42, and the third vibration region 43 in the vibration region 40 are obtained by making the thicknesses of the lower electrodes 8 different from each other. Is forming.
- the thickness of the lower electrode 8 in the first vibration region 41 is larger than the thickness of the lower electrode 8 in the third vibration region 43 by T.
- the thickness of the lower electrode 8 decreases from the outer portion in contact with the first vibration region 41 toward the inner portion in contact with the third vibration region 43.
- the upper surface of the lower electrode 8 is inclined with respect to the upper surface of the substrate 6 in the second vibration region 42 to be a slope-shaped upper surface.
- the thin film piezoelectric resonator according to the embodiment shown in FIGS. 7A and 7B can be manufactured as follows, for example.
- the formation method from the insulating layer to the sacrificial layer is the same as the embodiment described with reference to FIGS. 1A to 1C and others.
- the lower electrode 8 is formed by a film forming technique such as a sputtering method, a vapor deposition method, and a CVD method
- a predetermined amount of regions other than the first vibration region 41 and the second vibration region 42 are etched and removed by an etching technique such as RIE. To do.
- the processing is performed by the above-described RIE method so that the cross-sectional shape of the region serving as the second vibration region becomes a slope shape.
- the lower electrode 8 is patterned by the aforementioned etching technique so as to have a predetermined shape. Furthermore, after the piezoelectric layer 2 and the upper electrode 10 are formed by the above-described film forming method, each layer is patterned using the above-described patterning technique. Thereafter, as in the embodiment described with reference to FIGS. 1A to 1C, etc., a through hole 30 reaching from the upper surface of the upper electrode to the sacrificial layer is formed, and then the sacrificial layer and a part of the insulating layer are removed with an etching solution. Thus, the vibration space 4 is formed.
- FIG. 8A is an XX sectional view showing another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 8B is a YY sectional view showing the embodiment of FIG. 8A.
- This embodiment is different from the embodiment described with reference to FIGS. 1A to 1C and the like only in that an acoustic reflection layer 22 is provided instead of the air gap 4.
- the thin film piezoelectric resonator of the embodiment shown in FIGS. 8A and 8B can be manufactured, for example, as follows. After a pit portion is formed on a substrate 6 such as a silicon substrate by a technique such as wet etching, the acoustic reflection layer 22 is formed by the above-described film forming technique. Thereafter, the entire surface of the acoustic reflection layer 22 on the substrate is planarized by a planarization technique such as CMP, and the acoustic reflection layer 22 is deposited only in the pit portion.
- a planarization technique such as CMP
- a material having a small acoustic impedance such as SiO 2 or AlN is preferable as the low impedance layer, and a material having a large acoustic impedance such as Mo, W, Ta 2 O 5 is preferable as the high impedance layer.
- the acoustic reflection layer 22 is produced by alternately laminating a low impedance layer and a high impedance layer so that each thickness corresponds to a quarter wavelength of an elastic wave.
- the lower electrode 8, the piezoelectric layer 2, and the upper electrode 10 are formed by a film forming method such as sputtering or vapor deposition, and each layer is patterned using a patterning technique such as wet etching, RIE, or lift-off. Further, the frame layer 16 is formed by the above-described film forming technique and patterned by using the above-described patterning technique. At this time, the frame layer 16 is formed on the outer peripheral portion of the vibration region 40, and the end surface on the center side of the vibration region 40 is processed to have a slope shape to form the second vibration region 42. As a technique for achieving the slope shape, patterning by lift-off method or RIE is preferable.
- the vibration region 40 exists inside the outer peripheral edge of the acoustic reflection layer 22 when viewed in the thickness direction of the piezoelectric resonator stack 12.
- FIG. 9A is an XX sectional view showing another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 9B is a YY sectional view showing the embodiment of FIG. 9A.
- a lower dielectric layer 18 is formed below the lower electrode 8 and an upper dielectric layer 20 is formed on the upper electrode 10 in the embodiment described with reference to FIGS. 1A to 1C and others. Only that is different.
- the lower dielectric layer 18 and the upper dielectric layer 20 include aluminum nitride (AlN), aluminum oxynitride (AlON, such as AlOxNy (where x and y are, for example, 0.9 ⁇ x ⁇ 1.4,.
- Silicon nitride (Si 3 N 4 ), sialon (SiAlON), and the like are preferable, and those selected from the group consisting of these are preferable. It is preferably formed from a dielectric layer mainly composed of at least one material. Others are the same as in the embodiment described with reference to FIGS. 1A to 1C and the like, and can be manufactured by the same method.
- the thin film piezoelectric resonator having the lower dielectric layer 18 and / or the upper dielectric layer 20 as shown in FIGS. 9A and 9B is the thin film piezoelectric according to the embodiment described with reference to any of FIGS. 1A to 8B. Similar to the resonator, it is possible to suppress the occurrence of noise based on spurious due to another vibration mode or unnecessary thickness longitudinal vibration, and to obtain a high Q value. Furthermore, by providing the lower dielectric layer 18 and / or the upper dielectric layer 20, the lower electrode 8 and / or the upper electrode 10 can be protected.
- FIG. 10A is a schematic plan view showing another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 10B is a sectional view taken along line XX of FIG. 10A
- FIG. 10C is a sectional view taken along line YY of FIG. It is.
- the frame layer 16 exists in the buffer region 46 and the support region 48 in addition to the first vibration region 41 and the second vibration region 42 in the embodiment described with reference to FIGS. 1A to 1C and others. Only that is different.
- the frame layer 16 can have the same thickness over the first vibration region 41, the buffer region 46, and the support region 48.
- the frame layer 16 extends to the upper surface of the connection conductor 14 connected to the upper electrode 10.
- the electrical resistance in the connection conductor 14 can be reduced, the impedance (Rs) at the resonance frequency of the thin film piezoelectric resonator can be reduced, and the Q value can be reduced. (Qs) can be increased.
- a layer (vibration region defining layer) contributing to partitioning (defining) the vibration region 40 into a first vibration region 41, a second vibration region 42, and a third vibration region 43 That is, even when the upper electrode layer 10 or the lower electrode layer 8 is used as a layer having a slope in the vertical section in the second vibration region 42, the layer may be extended to the buffer region 46 and the support region 48. it can. Even in this case, the thickness of the vibration region defining layer can be made equivalent over the first vibration region 41, the buffer region 46, and the support region 48.
- the thin film piezoelectric filter By using a plurality of the thin film piezoelectric resonators of the present invention as described above, it is possible to configure a thin film piezoelectric filter that suppresses the occurrence of noise based on spurious due to another vibration mode or unnecessary thickness longitudinal vibration.
- the thin film piezoelectric filter include a filter in which thin film piezoelectric resonators as shown in FIG. 11 are arranged in a ladder type and a filter in which thin film piezoelectric resonators as shown in FIG. 12 are arranged in a lattice type. It is not limited.
- the ladder filter shown in FIG. 11 includes a series thin film piezoelectric resonator (131, 133, 135, 137) connected in series to the input / output port 104, and a node between the series thin film piezoelectric resonator and the ground. It consists of a parallel thin film piezoelectric resonator (132, 134, 136, 138) connected.
- the resonance frequency of the series thin film piezoelectric resonator is fs1
- the antiresonance frequency is fp1
- the resonance frequency of the parallel thin film piezoelectric resonator is fs2
- the antiresonance frequency is fp2
- fs1 and fp2 are the center of the bandpass filter.
- the resonator performance (Rs, Qs) near the resonance frequency of the series thin film piezoelectric resonator and the resonator performance (Rp, Qp) near the antiresonance frequency of the parallel thin film piezoelectric resonator are the passbands of the bandpass filter. Will greatly affect the performance.
- the thin film piezoelectric resonator according to the present invention has a feature that Rp at the antiresonance frequency can be increased and Qp can be increased.
- Rp at the antiresonance frequency it is possible to suppress the generation of noise in a frequency band lower than the resonance frequency, but the noise is larger than that of a thin film piezoelectric resonator having a uniform vibration region as shown in Comparative Example 5 described later. . Therefore, the thin film piezoelectric resonator according to the present invention is used only as a parallel thin film piezoelectric resonator of the ladder type filter shown in FIG. 11 and the lattice type filter shown in FIG. Utilizing the feature that Rp is one of the effects, it is possible to eliminate the influence of noise at a frequency lower than the resonance frequency, suppress the generation of noise in the passband, and reduce the insertion loss. A piezoelectric filter can be obtained.
- FIGS. 20A and 20C are an XX sectional view and a YY sectional view of FIG. 20A, respectively.
- the thin film piezoelectric resonator of the present embodiment supports the piezoelectric resonator stack 12 so as to form the piezoelectric resonator stack 12, the gap portion 4 formed below the piezoelectric resonator stack, and the gap portion 4. And a substrate 6 as a support member.
- the piezoelectric resonator stack 12 includes the piezoelectric layer 2 and the thickness direction of the piezoelectric layer 2, that is, the thickness direction of the piezoelectric resonator stack 12 (directions perpendicular to the paper surface in FIG. 20A, that is, XX direction and YY direction). It is a laminate including the lower electrode 8 and its external connection conductor 814 and the upper electrode 10 and its external connection conductor 1014 formed so as to be sandwiched in a direction perpendicular to both: the same applies hereinafter.
- the lower electrode 8 and the external connection conductor 814 are located below the piezoelectric layer 2 and are connected to each other.
- the upper electrode 10 and the external connection conductor 1014 are located on the upper side of the piezoelectric layer 2 and are connected to each other.
- the external connection conductors 814 and 1014 are conductive thin films formed to connect the upper electrode 8 and the lower electrode 10 to an external circuit (not shown), respectively, and are made of the same material as the upper electrode 8 and the lower electrode 10, respectively. Can be formed as the same layer.
- the boundary between the lower electrode 8 and the external connection conductor 814 or the boundary between the upper electrode 10 and the external connection conductor 1014 is an extension of the outline of the portion of the upper electrode or the lower electrode that is not in contact with the external connection conductor. To do.
- the external connection conductors 814 and 1014 correspond to the external connection conductor 14 in the embodiment of FIGS. 1A to 1C.
- the piezoelectric resonator stack 12 is not limited to a region where all of the piezoelectric layer 2, the upper electrode 8, the external connection conductor 814, the lower electrode 10, and the external connection conductor 1014 are formed. It includes even a region where is not formed.
- the piezoelectric resonator stack 12 includes a vibration region 16 ′ in which the upper electrode 10 and the lower electrode 8 overlap each other when viewed in the thickness direction of the piezoelectric resonator stack 12, a support region 17 in contact with the substrate 6, and a vibration region 16 ′. And a buffer region 20 ′ between the regions 17.
- the vibration region 16 ′ exists inside the outer peripheral edge of the gap portion 4 when viewed in the thickness direction of the piezoelectric resonator stack 12.
- the lower electrode 8 has a support portion 18 ′ having a width w ⁇ b> 1 extending in the support region 17 along the boundary between the support region 17 and the buffer region 20 ′.
- the support portion 18 ′ can be configured not to overlap the upper electrode 10 and the external connection conductor 1014 connected thereto when viewed in the thickness direction of the piezoelectric resonator stack 12.
- FIG. 21 shows the respective regions and portions in order to clarify the relationship among the vibration region 16 ′, the buffer region 20 ′, the support region 17 and the lower electrode support portion 18 ′ in the embodiment of FIGS. 20A to 20C. Is. Further, the region of the gap portion 4 viewed in the thickness direction of the piezoelectric resonator stack 12 is shown as a gap region 22 ′.
- the void region 22 ' corresponds to a region where the vibration region 16' and the buffer region 20 'are combined.
- the piezoelectric resonator stack 12 has the characteristic configuration described with reference to FIGS. 1A to 10C, and the vibration region 16 ′ has the above-described characteristics.
- the vibration region 40 includes first to third vibration regions 41 to 43. Therefore, as described with reference to FIGS. 1A to 10C, the piezoelectric resonator stack 12 is moved from the outer portion where the resonance frequency of the primary thickness longitudinal vibration in the second vibration region 42 is in contact with the first vibration region 41 to the third vibration region 43.
- An excellent thin film piezoelectric resonator having a high Q value that suppresses the occurrence of noise based on spurious due to another vibration mode or unnecessary longitudinal vibration by gradually increasing toward the inner part in contact with it. Is obtained.
- the thickness of the piezoelectric resonator stack 12 in the vibration region 16 ′ (referring to the thickness of the central portion of the vibration region 16 ′, that is, the third vibration region) is t
- the width w1 of the lower electrode support portion 18 ′ and the thickness t of the piezoelectric resonator stack 12 in the vibration region 16 ′ satisfy the relationship of 2.17 ⁇ w1 / t ⁇ 10, where the width of the buffer region 20 ′ is w2.
- the width w2 of the region 20 ′ and the thickness t of the piezoelectric resonator stack 12 in the vibration region 16 ′ satisfy the relationship of 0.25 ⁇ w2 / t ⁇ 2.
- the shape of the vibration region 16 ′ is an ellipse.
- the major axis diameter of the ellipse is a
- the minor axis diameter is b
- the major axis diameter a and the minor axis diameter b are 1 ⁇ a / Satisfies the relationship of b ⁇ 1.9.
- the substrate 6 is made of a silicon substrate, a gallium arsenide substrate, a glass substrate, or the like.
- the gap 4 can be formed by anisotropic wet etching, RIE (Reactive Ion Etching), or the like.
- the piezoelectric layer 2 may be made of a piezoelectric material that can be manufactured as a thin film, such as zinc oxide (ZnO) or aluminum nitride (AlN).
- the lower electrode 8 and the external connection conductor 814 and the upper electrode 10 and the external connection conductor 1014 are made of aluminum (Al), tungsten (W), molybdenum (Mo), platinum (Pt), ruthenium (Ru), iridium (Ir). Further, it may be made of a metal material that can be manufactured as a thin film and can be patterned, such as gold (Au), or may be made of a laminate of such thin films.
- the thin film piezoelectric resonator of the present embodiment can be manufactured as follows, for example. After a pit portion is formed on a substrate 6 such as a silicon wafer by a technique such as wet etching, a sacrificial layer is formed by a film forming technique such as a CVD method. Thereafter, the entire surface of the sacrificial layer and the substrate is planarized by a planarization technique such as CMP, and the sacrificial layer is deposited only in the pit portion.
- a material that is easily etched such as PSG (phospho-silicate glass), is suitable.
- a resonator stack 12 is formed. In the patterning at this time, the relationship between the width w1 of the lower electrode support portion 18 ′ and the thickness t of the piezoelectric resonator stack 12 in the vibration region 16 ′ and the width w2 of the buffer region 20 ′ and the vibration region 16 ′. The relationship with the thickness t of the piezoelectric resonator stack 12 is satisfied.
- the relationship between the major axis diameter a and the minor axis diameter b of the ellipse of the vibration region 16 ′ is satisfied. Further, the through hole 30 reaching the sacrificial layer from the upper surface of the piezoelectric resonator stack 12 is formed by using the patterning technique, and then the sacrificial layer is removed with an etching solution supplied through the through hole 30. As a result, the pit portion becomes the gap portion 4.
- FIG. 22A and 22B are schematic cross-sectional views showing another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 22A is a cross-sectional view corresponding to FIG. 20B
- FIG. 22B is a cross-sectional view corresponding to FIG. 20C.
- FIG. The plan view of this embodiment is the same as FIG. 20A.
- the substrate 6 is used as a support member, and the gap portion 4 is formed in the substrate 6.
- the substrate 6 having the insulating layer 7 in the upper layer portion is used.
- the gap 4 is formed by removing a part of the insulating layer 7. The rest is the same as the embodiment of FIGS. 20A to 20C.
- the thin film piezoelectric resonator of the embodiment of FIGS. 22A and 22B can be manufactured, for example, as follows.
- a silicon oxide (SiO 2 ) layer as an insulating layer is formed on a substrate 6 such as a silicon wafer by using a film forming technique such as a sputtering method and a CVD method, or by thermal oxidation.
- a sacrificial layer that is easily dissolved in an etching solution is formed by a film forming method such as sputtering or vapor deposition, and patterning is performed using a patterning technique such as wet etching, RIE, or lift-off, and the void 4 is formed.
- the sacrificial layer is left only in the region that should be.
- the sacrificial layer metals such as germanium (Ge), aluminum (Al), titanium (Ti), and magnesium (Mg) or oxides thereof are suitable.
- a film forming method such as a sputtering method and an evaporation method, and a patterning technique such as wet etching, RIE, and lift-off method.
- a piezoelectric resonator stack 12 is formed.
- the relationship with the thickness t of the piezoelectric resonator stack 12 is satisfied.
- the relationship between the major axis diameter a and the minor axis diameter b of the ellipse of the vibration region 16 ′ is satisfied.
- the through hole 30 reaching the sacrificial layer from the upper surface of the piezoelectric resonator stack 12 is formed by using the patterning technique, and then the sacrificial layer is removed with an etching solution supplied through the through hole 30. Furthermore, an etching solution capable of etching the SiO 2 layer is selected, and the SiO 2 layer can be etched in the same pattern as the sacrificial layer with the etching solution supplied through the through hole 30. Thereby, the space
- FIG. 23A and 23B are schematic cross-sectional views showing other embodiments of the thin film piezoelectric resonator of the present invention
- FIG. 23A is a cross-sectional view corresponding to FIG. 20B
- FIG. 23B is a cross-sectional view corresponding to FIG. 20C.
- FIG. The plan view of this embodiment is the same as FIG. 20A.
- FIGS. 23A and 23B is the same as the embodiment of FIGS. 20A to 20C in that the gap 4 is formed in the substrate 6, but the substrate is so formed that the gap 4 penetrates the substrate 6. It is different in that it is formed from the back side of.
- the gap 4 having such a configuration also corresponds to the gap formed between the substrate 6 and the piezoelectric resonator stack 12. The rest is the same as the embodiment of FIGS. 20A to 20C.
- the thin film piezoelectric resonator of the embodiment of FIGS. 23A and 23B can be manufactured as follows, for example.
- the lower electrode 8 and the external connection conductor 814, the piezoelectric layer 2, and the upper electrode 10 and the external connection conductor are formed on the substrate 6 by using a film forming method such as a sputtering method and a vapor deposition method and a patterning technique such as wet etching, RIE, and lift-off method.
- a piezoelectric resonator stack 12 consisting of 1014 is formed.
- the relationship with the thickness t of the piezoelectric resonator stack 12 is satisfied.
- the relationship between the major axis diameter a and the minor axis diameter b of the ellipse of the vibration region 16 ′ is satisfied.
- the gap 4 can be formed by etching from the back surface of the substrate 6 to the bottom of the piezoelectric resonator stack 12 by a deep etching technique such as anisotropic wet etching and Deep-RIE.
- FIG. 24A and 24B are schematic cross-sectional views showing still another embodiment of the thin film piezoelectric resonator of the present invention
- FIG. 24A is a cross-sectional view corresponding to FIG. 20B
- FIG. 24B corresponds to FIG. 20C. It is sectional drawing.
- the piezoelectric resonator stack 12 has a lower dielectric layer 24 below the lower electrode 8 and an upper dielectric layer 26 above the upper electrode 10. Yes.
- the dielectric layers 24 and 26 are preferably made of a material having a relatively large elastic modulus such as AlN, AlON, Si 3 N 4, and SiAlON. Others are the same as the embodiment of FIGS. 23A and 23B.
- the plan view of this embodiment is the same as FIG. 20A except for the dielectric layers 24 and 26.
- the lower dielectric layer 24 and / or the upper dielectric layer 26 it is possible to prevent oxidative deterioration of the lower electrode 8 and the external connection conductor 814 and / or the upper electrode 10 and the external connection conductor 1014. Further, when the lower dielectric layer 24 is provided, the lower dielectric layer 24 enhances the supporting force of the piezoelectric resonator stack 12, and thus a more robust thin film piezoelectric resonator can be realized.
- Table 1 shows the implementation conditions of Examples 1 to 28 and Comparative Examples 1 to 5 below, and Table 2 shows the electrical characteristics of the thin film piezoelectric resonators obtained in these Examples and Comparative Examples.
- Example 1 The shape of the upper electrode 10, that is, the shape of the vibration region 40 is an ellipse, and the ellipse has a major axis diameter a of 107 ⁇ m, a minor axis diameter b of 72 ⁇ m, and the shape of the through hole 30 is a square having a side of 5 ⁇ m.
- a thin film piezoelectric resonator described in 1C was produced.
- the thickness of each constituent layer in this example was set as follows.
- the lower electrode 8 is made of Mo and has a thickness of 300 nm
- the piezoelectric layer 2 is made of AlN and has a thickness of 1200 nm
- the upper electrode 10 is made of Ru and has a thickness of 300 nm.
- the frame layer 16 is made of Mo and has a thickness (T) of 100 nm, the first vibration region 41 has a width (Wt) of 3 ⁇ m, and the second vibration region 42 has a slope angle ⁇ of 20 °.
- the thin film piezoelectric resonator of Example 1 was manufactured as follows. On the silicon substrate 6 was formed an SiO 2 layer 7 is an insulating layer by thermal oxidation. Thereafter, a titanium (Ti) layer, which is a sacrificial layer, was formed by sputtering, and patterned by RIE. Thereafter, a Mo layer to be the lower electrode 8, an AlN layer to be the piezoelectric layer 2, and a Ru layer to be the upper electrode 10 were formed by sputtering, and each layer was patterned using the RIE method.
- Ti titanium
- a Mo layer to be the frame layer 16 was formed, and was patterned by the RIE method so that the end surface shape of the inner peripheral portion had a slope shape in accordance with the inner peripheral shape of the frame layer 16.
- the resist was formed so that the end portion of the resist had a slope shape, and then etching was performed by performing RIE using an etching gas as a mixed gas of Cl 2 gas and O 2 gas.
- the slope angle ⁇ of the inner peripheral end face of the frame layer 16 was set to 20 °.
- the upper electrode 10 and the frame layer 16 were etched by the RIE method using Cl 2 gas as an etching gas in accordance with the outer peripheral shape of the frame layer 16. Further, a through hole 30 reaching from the upper surface of the upper electrode 10 to the sacrificial layer was formed by RIE, and then the sacrificial layer and a part of the insulating layer 7 were removed by etching with hydrofluoric acid as an etchant. The vibration space 4 was formed in the sacrificial layer and the insulating layer 7 thus removed.
- the lower electrode 8 is made larger than the sacrificial layer by a predetermined shape
- the upper electrode 10 is made smaller than the sacrificial layer by a predetermined shape, so that the buffer region 46 is formed on the air gap 4 and the support region 48 is further formed on the insulating layer 7 of the substrate 6. Formed.
- FIG. 13A and FIG. 13B show the frequency characteristics and Smith chart of the impedance of the resonator thus manufactured, respectively. It can be seen that noise generation is suppressed in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof. In the following examples and comparative examples, the noise level shown in FIGS. 13A and 13B was evaluated as “low”. Further, the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2600 ⁇ , and the Q value (Qp) was 1430, which was a high value.
- Examples 2 to 5 1A to 1C in the same manner as in Example 1 except that the slope angle ⁇ of the cross section in the second vibration region 42 of the frame layer 16 is 30 °, 45 °, 60 °, and 70 ° as shown in Table 1.
- the thin film piezoelectric resonator described in 1 was produced.
- the slope angle ⁇ of the inner peripheral end face of the frame layer 16 was adjusted by adjusting the O 2 gas flow rate of the etching gas. In this case, the width (Ws) of the second vibration region 42 was 0.04 to 0.17 ⁇ m.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2380 to 2740 ⁇ , and the Q value (Qp) was 1420 to 1500, indicating a high value.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- “medium” means “small” as shown in FIGS. 13A and 13B and “large” as shown in FIGS. 14A and 14B described later. Means the middle level.
- Example 1 A thin film piezoelectric resonator as shown in FIGS. 1A to 1C was manufactured in the same manner as in Example 1 except that the slope angle ⁇ of the cross section in the second vibration region 42 of the frame layer 16 was set to 90 °. In this case, the width (Ws) of the second vibration region 42 was 0 ⁇ m.
- FIG. 14A and FIG. 14B show impedance frequency characteristics and Smith charts of the resonators thus fabricated, respectively.
- the noise level shown in FIGS. 14A and 14B was evaluated as “high”.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator is 2060 ⁇ , which is smaller than those in Examples 1 to 5.
- the Q value (Qp) is 1260, which is smaller than those in the first to fifth embodiments.
- the width (Wt) of the first vibration region 41 is 1.5 ⁇ m, 4.0 ⁇ m, and 6.0 ⁇ m, and the slope angle ⁇ of the cross section of the frame layer 16 in the second vibration region 42 is 45 °, 60 ⁇ m.
- a thin film piezoelectric resonator shown in FIGS. 1A to 1C was fabricated in the same manner as in Example 1 except that the angle was set to 0 °. In this case, the width (Ws) of the second vibration region 42 was 0.10 ⁇ m and 0.06 ⁇ m.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2220 to 2480 ⁇ , and the Q value (Qp) was as high as 1330 to 1430.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- Example 1 (Comparative Examples 2 to 4) Example 1 except that the width (Wt) of the first vibration region 41 is 1.5 ⁇ m, 4.0 ⁇ m, 6.0 ⁇ m, and the slope angle ⁇ of the cross section of the frame layer 16 in the second vibration region 42 is 90 °. Similarly, a thin film piezoelectric resonator as shown in FIGS. 1A to 1C was manufactured. In this case, the width (Ws) of the second vibration region 42 was 0 ⁇ m.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator is 1880-2080 ⁇ , which is smaller than those of Examples 6-11.
- the Q value (Qp) is 1200 to 1270, which is smaller than those in Examples 6 to 11. It can also be seen that the noise level in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof is large, and the generation of noise is large.
- Example 12 The thin film piezoelectric resonator shown in FIGS. 10A to 10C having the frame layer 16 extended to the upper surface of the external connection conductor 14 of the upper electrode 10 in the buffer region 46 and the support region 48 was produced.
- the thickness of the frame layer 16 is the same, that is, constant over the first vibration region 41, the buffer region 46, and the support region 48.
- the third embodiment is the same as the third embodiment except that the frame layer 16 is expanded.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2740 ⁇ , and the Q value (Qp) was 1500, which was a high value.
- the magnitude of noise in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof is “small” as shown in the noise level in Table 2, and it can be seen that the generation of noise can be suppressed.
- the impedance (Rs) at the resonance frequency is as small as 1.1 ⁇ and the Q value (Qs) is as large as 1580 as compared with the other examples.
- the constituent layer (vibration region defining layer) defining the first to third vibration regions 41 to 43 is the Ru upper electrode layer 10, and the increased thickness T of the upper electrode layer 10 in the first vibration region 41 is 120 nm.
- the slope angle ⁇ of the cross section in the second vibration region 42 was set to 45 °, 60 °, and 70 °, and the thin film piezoelectric resonator shown in FIGS. 6A and 6B was manufactured. In this case, the width (Ws) of the second vibration region 42 was 0.04 to 0.12 ⁇ m.
- the thickness and material of each constituent layer were the same as in Example 1.
- the thin film piezoelectric resonators of Examples 13 to 15 were manufactured as follows. On the silicon substrate 6 was formed an SiO 2 layer 7 is an insulating layer by thermal oxidation. Thereafter, a titanium (Ti) layer, which is a sacrificial layer, was formed by sputtering, and patterned by RIE. Then, while forming Mo layer used as a lower electrode and AlN layer used as a piezoelectric layer by sputtering method, each layer was patterned using RIE method. Further, a Ru layer to be the upper electrode 10 is formed, and in accordance with the shape of the second vibration region 42, the Ru layer is formed so that the end surface shape of the inner peripheral portion in the second vibration region 42 becomes a slope shape by the RIE method.
- the resist was formed so that the end portion of the resist had a slope shape, and then etching was performed by performing RIE using an etching gas as a mixed gas of CF 4 gas and O 2 gas. Thereafter, the upper electrode 10 was etched by the RIE method using CF 4 gas as an etching gas in accordance with the outer peripheral shape of the upper electrode 10. Further, a through hole 30 reaching from the upper surface of the upper electrode 10 to the sacrificial layer was formed by RIE, and then the sacrificial layer and a part of the insulating layer 7 were removed by etching with hydrofluoric acid as an etchant. The vibration space 4 was formed in the sacrificial layer and the insulating layer 7 thus removed.
- the lower electrode 8 is made larger than the sacrificial layer by a predetermined shape
- the upper electrode 10 is made smaller than the sacrificial layer by a predetermined shape, so that the buffer region 46 is formed on the air gap 4 and the support region 48 is further formed on the insulating layer 7 of the substrate 6. Formed.
- Table 2 shows the impedance (Rp), the Q value (Qp), and the noise level at the antiresonance frequency of the thin film piezoelectric resonator obtained.
- the obtained thin film piezoelectric resonator had a large impedance (Rp) at the antiresonance frequency of 2330 to 2640 ⁇ and a high Q value (Qp) of 1400 to 1450.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- the constituent layer (vibration region defining layer) defining the first to third vibration regions 41 to 43 is the Mo lower electrode layer 8, and the increased thickness T of the lower electrode layer 8 in the first vibration region 41 is 120 nm.
- the slope angle ⁇ of the cross section in the second vibration region 42 was set to 45 °, 60 °, and 70 °, and the thin film piezoelectric resonator shown in FIGS. 7A and 7B was manufactured. In this case, the width (Ws) of the second vibration region 42 was 0.04 to 0.12 ⁇ m.
- the thickness and material of each constituent layer were the same as in Example 1.
- the thin film piezoelectric resonators of Examples 17 to 19 were manufactured as follows. On the silicon substrate 6 was formed an SiO 2 layer 7 is an insulating layer by thermal oxidation. Thereafter, a titanium (Ti) layer, which is a sacrificial layer, was formed by sputtering, and patterned by RIE. Thereafter, a Mo layer to be the lower electrode 8 is formed by sputtering, and the end surface shape of the inner peripheral portion in the second vibration region 42 is sloped by the RIE method in accordance with the shape of the second vibration region 42. The Mo layer was patterned.
- the resist was formed so that the end portion of the resist had a slope shape, and then etching was performed by performing RIE using an etching gas as a mixed gas of Cl 2 gas and O 2 gas. Thereafter, the lower electrode was etched by the RIE method using Cl 2 gas as an etching gas in accordance with the outer peripheral shape of the lower electrode 8. Thereafter, an AlN layer as the piezoelectric layer 2 and a Ru layer as the upper electrode 10 were formed and patterned by the RIE method.
- a through hole 30 reaching from the upper surface of the upper electrode 10 to the sacrificial layer was formed by RIE, and then the sacrificial layer and a part of the insulating layer 7 were removed by etching with hydrofluoric acid as an etchant.
- the vibration space 4 was formed in the sacrificial layer and the insulating layer 7 thus removed.
- the lower electrode 8 is made larger than the sacrificial layer by a predetermined shape
- the upper electrode 10 is made smaller than the sacrificial layer by a predetermined shape, so that the buffer region 46 is formed on the air gap 4 and the support region 48 is further formed on the insulating layer 7 of the substrate 6. Formed.
- Table 2 shows the impedance (Rp), the Q value (Qp), and the noise level at the antiresonance frequency of the thin film piezoelectric resonator obtained.
- the obtained thin film piezoelectric resonator had a large impedance (Rp) at the antiresonance frequency of 2330 to 2600 ⁇ and a high Q value (Qp) of 1400 to 1450.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- Example 16 and 20 A portion where the thickness of the upper electrode 10 or the lower electrode 8 which is a constituent layer (vibration region defining layer) that defines the first to third vibration regions 41 to 43 is increased in the buffer region 46 and the support region 48.
- a thin film piezoelectric resonator was manufactured in the same manner as in Example 13 or 17 except that the external connection conductor 14 of the upper electrode or the lower electrode was extended.
- the upper electrode 10 or the lower electrode 8 that is the vibration region defining layer has the same thickness, that is, constant over the first vibration region 41, the buffer region 46, and the support region 48.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2620 ⁇ and 2630 ⁇ , and the Q value (Qp) was 1450 and 1420, indicating a high value.
- the magnitude of noise in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof is “small” as shown in the noise level in Table 2, and it can be seen that the generation of noise can be suppressed.
- the impedance (Rs) at the resonance frequency is as small as 1.2 ⁇ and 1.1 ⁇
- the Q value It can be seen that Qs) is as large as 1530 and 1590.
- Example 21 and 22 Thin film piezoelectric resonators similar to those in Examples 3 and 4 were manufactured except that the material used for the frame layer 16 was aluminum (Al) and the thickness T of the frame layer was 200 nm. In this case, the width (Ws) of the second vibration region 42 was 0.20 ⁇ m and 0.12 ⁇ m.
- Table 2 shows the impedance (Rp), the Q value (Qp), and the noise level at the antiresonance frequency of the thin film piezoelectric resonator obtained.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was 2200 ⁇ , 2180 ⁇ , and the Q value (Qp) was 1330, 1320. It can be seen that the resonance characteristics at the antiresonance frequency are slightly deteriorated as compared with Examples 3 and 4.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- Example 23 and 24 Thin film piezoelectric resonators similar to those in Examples 3 and 4 were produced except that the material used for the frame layer 16 was gold (Au). In this case, the width (Ws) of the second vibration region 42 was 0.10 ⁇ m and 0.06 ⁇ m.
- Table 2 shows the impedance (Rp), the Q value (Qp), and the noise level at the antiresonance frequency of the thin film piezoelectric resonator obtained.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was 2220 ⁇ , 2190 ⁇ , and the Q value (Qp) was 1330, 1320. It can be seen that the resonance characteristics at the antiresonance frequency are slightly deteriorated as compared with Examples 3 and 4.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- Example 25 and 26 Thin film piezoelectric resonators similar to those in Examples 3 and 4 were produced except that the material used for the frame layer 16 was tungsten (W). In this case, the width (Ws) of the second vibration region 42 was 0.10 ⁇ m and 0.06 ⁇ m.
- Table 2 shows the impedance (Rp), the Q value (Qp), and the magnitude of the noise level at the antiresonance frequency of the thin film piezoelectric resonator obtained.
- the obtained thin film piezoelectric resonator had large impedances (Rp) at antiresonance frequencies of 2680 ⁇ and 2620 ⁇ , and high Q values (Qp) of 1480 and 1450.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize.
- kt 2 is 6.0% and 6.1%, which are slightly lower than those in Examples 3 and 4.
- Example 27 and 28 Thin film piezoelectric resonators similar to those in Examples 3 and 4 were manufactured except that the material used for the frame layer 16 was iridium (Ir) and the thickness T of the frame layer was 80 nm. In this case, the width (Ws) of the second vibration region 42 was 0.08 ⁇ m and 0.05 ⁇ m.
- Table 2 shows the impedance (Rp), the Q value (Qp), and the magnitude of the noise level at the antiresonance frequency of the thin film piezoelectric resonator obtained.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2420 ⁇ and 2400 ⁇ , and the Q value (Qp) was 1430 and 1400, indicating a high value.
- the noise level in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is small or medium as shown in the noise level in Table 2, and the generation of noise can be suppressed. Recognize. Further, kt 2 is 5.8%, which is lower than those in Examples 3 and 4.
- Example 5 A thin film piezoelectric resonator similar to that of Example 1 was produced except that the frame layer 16 was not formed.
- FIG. 15A and FIG. 15B show the impedance frequency characteristics and Smith charts of the resonators thus fabricated, respectively.
- Table 2 shows the electrical characteristics of the thin film piezoelectric resonator obtained. Although the generation of noise in the frequency band lower than the resonance frequency is extremely small, it can be seen that Rp at the antiresonance frequency is as small as 1320 ⁇ and the Q value (Qp) is as small as 820.
- Example 29 In the thin film piezoelectric resonator shown in FIGS. 1A to 1C, a ladder type thin film piezoelectric filter shown in FIG. 11 was manufactured using a thin film piezoelectric resonator having the same conditions as those of Example 12 for the frame layer 16.
- the frame layer 16 of the thin film piezoelectric resonator shown in the twelfth embodiment is applied to both the series thin film piezoelectric resonator and the parallel thin film piezoelectric resonator.
- Fig. 16 shows the pass characteristics of the thin film piezoelectric filter.
- the insertion loss in the pass band (1920 to 1980 MHz) is smaller than the pass characteristic of the thin film piezoelectric filter of Comparative Example 6 which will be described later manufactured only by the thin film piezoelectric resonator having no frame layer 16. Recognize. However, it can be seen that noise occurs in the low band side of the pass band (1920 to 1940 MHz) and in the attenuation band of 1800 to 1900 MHz.
- Example 30 In the thin film piezoelectric resonator shown in FIGS. 1A to 1C, a ladder type thin film piezoelectric filter shown in FIG. 11 was manufactured using a thin film piezoelectric resonator having the same conditions as those of Example 12 for the frame layer 16.
- the thin film piezoelectric resonator frame layer 16 shown in the twelfth embodiment is applied only to the parallel thin film piezoelectric resonator, and the others are thin film piezoelectric resonators having no frame layer.
- Fig. 16 shows the pass characteristics of the thin film piezoelectric filter.
- the insertion loss in the pass band (1920 to 1980 MHz) is smaller than the pass characteristic of the thin film piezoelectric filter of Comparative Example 6 which will be described later manufactured only by the thin film piezoelectric resonator having no frame layer 16. Recognize.
- Example 29 it can be seen that the occurrence of noise on the low band side of the pass band is suppressed, and that it has extremely good pass characteristics.
- Fig. 16 shows the pass characteristics of the thin film piezoelectric filter. It can be seen that the insertion loss in the pass band (1920 to 1980 MHz) is larger than the pass characteristics of the thin film piezoelectric filters of Examples 29 and 30 manufactured by the thin film piezoelectric resonator having the frame layer 16. .
- Examples 31 to 33 The sacrificial layer size was adjusted in the same manner as in Example 3 except that the width of the buffer region 46 (W2 shown in FIG. 20A and others) was 2 ⁇ m, and the lower electrode 8 had a major axis diameter a.
- Thin film piezoelectric is set so that the minor axis diameter b is 121 to 147 ⁇ m and the minor axis diameter b is 86 to 112 ⁇ m, that is, the width of the support portion 18 ′ (W1 shown in FIG. 20A and others) is 5 to 18 ⁇ m.
- a resonator was fabricated. Table 3 shows the implementation conditions, and Table 4 shows the electrical characteristics and the like of the thin film piezoelectric resonator obtained.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2480 to 2740 ⁇ , and the Q value (Qp) was as high as 1430 to 1500.
- the noise level in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof is “small” as shown in the noise level in Table 4, and the generation of noise can be suppressed. Recognize. Furthermore, the breakage of the resonator in the manufacturing process is suppressed, and the manufacturing yield is very excellent at 90% or more.
- a thin film piezoelectric resonator was fabricated in the same manner as in Example 31, except that the width (W1) of the support portion 18 ′ was ⁇ 5 ⁇ m, 1 ⁇ m, and 20 ⁇ m.
- Table 3 shows the implementation conditions
- Table 4 shows the electrical characteristics and the like of the thin film piezoelectric resonator obtained. Note that W1 in the case where the outer peripheral edge of the lower electrode exists inside the gap as viewed in the thickness direction of the piezoelectric resonator stack is indicated by a minus sign.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator is 1540 to 1760 ⁇ , which is smaller than those of Examples 31 to 33, and the Q value (Qp) is 980. It can be seen that it is smaller than ⁇ 1100 and Examples 31 to 33.
- the magnitude of noise in the frequency band from the resonance frequency to the anti-resonance frequency and in the vicinity thereof is “large” in Comparative Example 7 and “medium” in Comparative Example 8, and Examples 31 to 33 It can be seen that the generation of noise is larger than.
- Example 34 A thin film piezoelectric resonator was fabricated in the same manner as in Example 31 except that the width (W2) of the buffer region 46 was 1 ⁇ m and 3 ⁇ m.
- Table 3 shows the implementation conditions, and Table 4 shows the electrical characteristics and the like of the thin film piezoelectric resonator obtained.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator was as large as 2410 ⁇ , 2210 ⁇ , and the Q value (Qp) was 1400 and 1320, indicating a high value.
- the noise level in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof is “small” as shown in the noise level in Table 4, and the generation of noise can be suppressed. Recognize. Further, the breakage of the resonator in the manufacturing process is suppressed, and the manufacturing yield is very excellent at 91% or more.
- a thin film piezoelectric resonator was manufactured in the same manner as in Example 31 except that the width (W2) of the buffer region 46 was set to 0 ⁇ m and 4 ⁇ m.
- Table 3 shows the implementation conditions, and Table 4 shows the electrical characteristics and the like of the thin film piezoelectric resonator obtained.
- the impedance (Rp) at the antiresonance frequency of the obtained thin film piezoelectric resonator is 1460 ⁇ and 1750 ⁇ , which are smaller than those of Examples 34 and 35, and the Q value (Qp) is 960. 1090 is smaller than those of Examples 34 and 35.
- kt 2 is 5.9% and 6.0%, respectively, which are smaller than those in Examples 34 and 35.
- the magnitude of noise in the frequency band between the resonance frequency and the anti-resonance frequency and in the vicinity thereof is “medium” in Comparative Example 11, and noise generation is larger than in Examples 34 and 35. Recognize. Further, Comparative Example 11 is not preferable because the resonator is damaged in the manufacturing process and the manufacturing yield is reduced to 80%.
- the frame layer 16 is not formed, and the lower electrode 8 and its external connection conductor 814 and the upper electrode 10 and its external connection conductor 1014 have the same thickness over the vibration region 16 ′, the buffer region 20 ′, and the support region 17. It was supposed to have.
- the material and thickness of each constituent layer in this example were set as follows.
- the lower electrode 8 and the external connection conductor 814 are made of Mo with a thickness of 300 nm
- the piezoelectric layer 2 is made of material AlN with a thickness of 1700 nm
- the upper electrode 10 and the external connection conductor 1014 are made of material Mo with a thickness of 200 nm.
- the thickness t of the stack 12 was 2.2 ⁇ m.
- the Q value becomes a large value, showing good resonator characteristics, and suppressing breakage of the resonator in the manufacturing process.
- the production yield is very excellent at 90% or more.
- Example 12 A piezoelectric thin film resonator was manufactured in the same manner as in Example 36 except that the value of the width w1 of the lower electrode support portion 18 was changed to the value shown in Table 5. The results are shown in FIG. Note that w1 in the case where the outer peripheral edge of the lower electrode exists inside the gap as viewed in the thickness direction of the piezoelectric resonator stack is indicated by a minus sign. As can be seen from FIG. 25 and Table 5, a thin film piezoelectric resonator manufactured under the conditions of w1 / t> 10 and other conditions equivalent to Example 36 is not preferable because the Q value becomes small.
- the Q value becomes small, and the resonator is damaged in the manufacturing process. This is not preferable because the yield in the manufacturing process is lowered.
- the material and thickness of each constituent layer in this example were the same as in Example 36.
- the effective kt 2 and the Q value are large values, indicating good resonator characteristics. Further, the breakage of the resonator in the manufacturing process is suppressed, and the manufacturing yield is very excellent at 90% or more.
- a thin film piezoelectric resonator having the form shown in FIGS.
- Example 47 As the lower dielectric layer 24 and the upper dielectric layer 26, thin film piezoelectric resonators of the form shown in FIGS. 24A and 24B were manufactured using materials of AlN and thicknesses of 0.05 ⁇ m, respectively.
- the constituent layers of the piezoelectric resonator stack 12 other than the lower dielectric layer 24 and the upper dielectric layer 26 in this example were the same as those in the example 36.
- the results are shown in Table 5.
- the obtained thin film piezoelectric resonator has a large effective kt 2 and a high Q value. Even when the lower dielectric layer 24 and the upper dielectric layer 26 are added, the thin film piezoelectric resonator having excellent characteristics is obtained. It can be seen that a vessel is obtained. Further, the breakage of the resonator in the manufacturing process is suppressed, and the manufacturing yield is remarkably excellent at 97%.
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Abstract
Description
基板と、該基板上にあって、圧電層と該圧電層を挟んで互いに対向するように形成された上部電極及び下部電極とを有する圧電共振器スタックと、前記基板と前記圧電共振器スタックとの間に形成された空隙または音響反射層と、を含んでなる薄膜圧電共振器であって、
前記圧電共振器スタックは、該圧電共振器スタックの厚み方向に見て前記上部電極と前記下部電極とが互いに重なる振動領域を有し、
該振動領域は第1振動領域、第2振動領域及び第3振動領域からなり、
前記圧電共振器スタックの厚み方向に見て、前記第1振動領域は最外側に存在し、前記第3振動領域は最内側に存在し且つ前記第1振動領域とは接しておらず、前記第2振動領域は前記第1振動領域と前記第3振動領域との間に介在しており、
前記振動領域の一次厚み縦振動の共振周波数は、前記第1振動領域においてf1であり、前記第3振動領域においてf2であり、ここで前記f1と前記f2とがf1<f2の関係を満たし、前記第2振動領域においては前記第1振動領域に接する外側部分から前記第3振動領域に接する内側部分に向かってf1からf2の間の値をとりながら増加していることを特徴とする薄膜圧電共振器、
が提供される。これによれば、別の振動モードや不要な厚み縦振動に起因するスプリアスに基づくノイズの発生を抑制するとともに、高いQ値と大きなkt2を有する薄膜圧電共振器を提供することができる。
上部電極10の形状即ち振動領域40の形状が楕円形で、該楕円の長軸径aが107μmで短軸径bが72μmで、貫通孔30の形状が一辺5μmの正方形とした図1A~図1Cに記載の薄膜圧電共振器を作製した。本実施例での各構成層の厚みは次のように設定した。下部電極8は材質がMoで厚みが300nm、圧電層2は材質がAlNで厚みが1200nm、上部電極10は材質がRuで厚みが300nmとした。さらに、フレーム層16は材質がMoで厚み(T)が100nmとし、第1振動領域41は幅(Wt)が3μmとし、第2振動領域42はスロープ角度θが20°とした。この場合、幅(Ws)は0.27μm(Ws=T/tanθ)となる。
フレーム層16の第2振動領域42における断面のスロープ角度θを表1に示すように30°、45°、60°、70°とした以外は実施例1と同様にして、図1A~図1Cに記載の薄膜圧電共振器を作製した。フレーム層16の内周部端面のスロープ角度θの調整は、エッチングガスのO2ガス流量を調整することによって行った。この場合、第2振動領域42の幅(Ws)は0.04~0.17μmとなった。
フレーム層16の第2振動領域42における断面のスロープ角度θを90°とした以外は実施例1と同様にして、図1A~図1Cに記載の様な薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0μmとなった。
第1振動領域41の幅(Wt)を表1で示すように1.5μm、4.0μm、6.0μmとし、第2振動領域42におけるフレーム層16の断面のスロープ角度θを45°、60°とした以外は実施例1と同様にして、図1A~図1Cに記載の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.10μm、0.06μmとなった。
第1振動領域41の幅(Wt)を1.5μm、4.0μm、6.0μmとし、第2振動領域42におけるフレーム層16の断面のスロープ角度θを90°とした以外は実施例1と同様にして、図1A~図1Cに記載の様な薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0μmとなった。
緩衝領域46及び支持領域48における上部電極10の外部接続導体14の上面上にまで拡張したフレーム層16を有する図10A~図10Cに記載の薄膜圧電共振器を作製した。ここで、フレーム層16は、第1振動領域41、緩衝領域46及び支持領域48に亘って厚みが同一すなわち一定であった。フレーム層16が拡張されていること以外は、実施例3と同様である。
第1~第3の振動領域41~43を画定している構成層(振動領域画定層)をRu上部電極層10とし、第1振動領域41における上部電極層10の増加した厚みTを120nmとし、第2振動領域42における断面のスロープ角度θを45°、60°、70°として、図6A及び図6Bに記載の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.04~0.12μmとなった。各構成層の厚みおよび材質は、実施例1と同様とした。
第1~第3の振動領域41~43を画定している構成層(振動領域画定層)をMo下部電極層8とし、第1振動領域41における下部電極層8の増加した厚みTを120nmとし、第2振動領域42における断面のスロープ角度θを45°、60°、70°として、図7A及び図7Bに記載の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.04~0.12μmとなった。各構成層の厚みおよび材質は、実施例1と同様とした。
第1~第3の振動領域41~43を画定している構成層(振動領域画定層)である上部電極10または下部電極8の厚みを増している部分を、緩衝領域46及び支持領域48における上部電極または下部電極の外部接続導体14にまで拡張した以外は、実施例13または17と同様にして薄膜圧電共振器を作製した。ここで、振動領域画定層である上部電極10または下部電極8は、第1振動領域41、緩衝領域46及び支持領域48に亘って厚みが同一すなわち一定であった。
フレーム層16に用いる材質をアルミニウム(Al)とし、フレーム層の厚みTを200nmとした以外は実施例3及び4と同様の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.20μm、0.12μmとなった。
フレーム層16に用いる材質を金(Au)とした以外は実施例3及び4と同様の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.10μm、0.06μmとなった。
フレーム層16に用いる材質をタングステン(W)とした以外は実施例3及び4と同様の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.10μm、0.06μmとなった。
フレーム層16に用いる材質をイリジウム(Ir)とし、フレーム層の厚みTを80nmとした以外は実施例3及び4と同様の薄膜圧電共振器を作製した。この場合、第2振動領域42の幅(Ws)は0.08μm、0.05μmとなった。
フレーム層16を形成していない以外は実施例1と同様の薄膜圧電共振器を作製した。
図1A~図1Cに記載の薄膜圧電共振器において、フレーム層16に関する条件は実施例12と同様とした薄膜圧電共振器を用いて、図11に示すラダー型の薄膜圧電フィルタを作製した。本実施例では、直列薄膜圧電共振器および並列薄膜圧電共振器の双方に実施例12で示した薄膜圧電共振器のフレーム層16を適用した。
図1A~図1Cに記載の薄膜圧電共振器において、フレーム層16に関する条件は実施例12と同様とした薄膜圧電共振器を用いて、図11に示すラダー型の薄膜圧電フィルタを作製した。本実施例では、並列薄膜圧電共振器にのみ実施例12で示した薄膜圧電共振器のフレーム層16を適用し、他はフレーム層を有していない薄膜圧電共振器とした。
図17に示す形態で、構成層に関する条件は比較例5と同様とした薄膜圧電共振器を用いて、図11に示すラダー型の薄膜圧電フィルタを作製した。
実施例3と同様にして、但し、緩衝領域46の幅(図20A他に示されているW2)が2μmとなるように犠牲層サイズを調整し、更に、下部電極8は長軸径aが121~147μmで、短軸径bが86~112μmとなる様に、つまり支持部分18’の幅(図20A他に示されているW1)が5~18μmとなるように設定して、薄膜圧電共振器を作製した。表3に実施条件を、表4に得られた薄膜圧電共振器の電気特性等を示す。
支持部分18’の幅(W1)を-5μm、1μm、20μmとした以外は、実施例31と同様にして、薄膜圧電共振器を作製した。表3に実施条件を、表4に得られた薄膜圧電共振器の電気特性等を示す。尚、圧電共振器スタックの厚み方向に見て下部電極の外周縁が空隙部の内側に存在する場合のW1は、マイナス符号を付して表記している。
緩衝領域46の幅(W2)を1μm、3μmとした以外は、実施例31と同様にして、薄膜圧電共振器を作製した。表3に実施条件を、表4に得られた薄膜圧電共振器の電気特性等を示す。
緩衝領域46の幅(W2)を0μmと4μmとした以外は、実施例31と同様にして、薄膜圧電共振器を作製した。表3に実施条件を、表4に得られた薄膜圧電共振器の電気特性等を示す。
上部電極10の形状即ち振動領域16’の形状が楕円形で、該楕円の長軸径a=180μmで短軸径b=140μmとした図20A~図20Cの形態の薄膜圧電共振器を作製した。但し、フレーム層16は形成されておらず、振動領域16’、緩衝領域20’及び支持領域17にわたって下部電極8及びその外部接続導体814並びに上部電極10及びその外部接続導体1014はそれぞれ同等の厚みを有するものとした。本実施例での各構成層の材質及び厚みは次のように設定した。下部電極8及び外部接続導体814を材質Moで厚み300nm、圧電層2を材質AlNで厚み1700nm、上部電極10及び外部接続導体1014を材質Moで厚み200nm、即ち、振動領域16’の圧電共振器スタック12の厚みtを2.2μmとした。緩衝領域20’の幅w2を2μm(w2/t=0.91)とした場合の、下部電極支持部分18’の幅w1と薄膜圧電共振器の実効的kt2およびQ値との関係を図25および表5に示す。図25および表5からわかるように、2.17≦w1/t≦10の範囲内では、Q値は大きな値となり、良好な共振器特性を示すとともに、製造工程における共振器の破損が抑制されており、製造歩留まりは90%以上と非常に優れている。
下部電極支持部分18の幅w1の値を表5に記載の値にした以外は、実施例36と同様にして、圧電薄膜共振器を作製した。結果を図25および表5に示す。尚、圧電共振器スタックの厚み方向に見て下部電極の外周縁が空隙部の内側に存在する場合のw1は、マイナス符号を付して表記している。図25および表5からわかるように、w1/t>10の条件で且つ他の条件は実施例36と同等にして作製した薄膜圧電共振器では、Q値が小さくなり好ましくない。また、w1/t<2.17の条件で且つ他の条件は実施例36と同等にして作製した薄膜圧電共振器では、Q値が小さくなるとともに、製造工程における共振器の破損が発生し、製造工程における歩留まりが低下するため好ましくない。
上部電極10の形状即ち振動領域16’の形状が楕円形で、該楕円の長軸径a=180μmで短軸径b=140μmとした図20A~図20Cの形態の薄膜圧電共振器を作製した。本実施例での各構成層の材質及び厚みは実施例36と同様にした。下部電極支持部分18’の幅w1を5μm(w1/t=2.27)とした場合の、緩衝領域20’の幅w2と薄膜圧電共振器の実効的kt2およびQ値との関係を図26および表5に示す。図26および表5からわかるように、0.25≦w2/t≦2の範囲内では、実効的kt2とQ値は大きな値となり、良好な共振器特性を示す。また、製造工程における共振器の破損は抑制され、製造歩留まりは90%以上と非常に優れている。
緩衝領域の幅w2の値を表5に記載の値にした以外は、実施例40と同様にして、圧電薄膜共振器を作製した。結果を図26および表5に示す。尚、圧電共振器スタックの厚み方向に見て空隙部が上部電極の外周縁の内側に存在する場合のw2は、マイナス符号を付して表記している。図26および表5からわかるように、w2/t<0.25またはw2/t>2の条件で且つ他の条件は実施例40と同等にして作製した薄膜圧電共振器では、実効的kt2またはQ値が小さくなり好ましくない。
上部電極10の形状即ち振動領域16’の形状が楕円形で、該楕円の長軸径a及び短軸径bを、a=195μm、b=130μm(a/b=1.50)、a=210μm、b=120μm(a/b=1.75)、a=220μm、b=115μm(a/b=1.91)、a=230μm、b=110μm(a/b=2.09)とし、下部電極支持部分18’の幅w1を5μmとし、緩衝領域20’の幅w2を2μmとした図20A~図20Cの形態の薄膜圧電共振器を作製した。本実施例での各構成層の材質及び厚みは実施例36と同様にした。結果を表5に示す。表5からわかるように、1<a/b≦1.9の範囲内とすることにより、より大きな実効的kt2と高いQ値とを有する薄膜圧電共振器が得られており好ましい。さらに、製造工程における共振器の破損は抑制されており、製造歩留まりは80%以上と優れている。
下部誘電体層24および上部誘電体層26として、それぞれ材質AlNで厚み0.05μmのものを使用して図24A及び図24Bの形態の薄膜圧電共振器を作製した。本実施例での下部誘電体層24および上部誘電体層26以外の圧電共振器スタック12の各構成層は実施例36と同様にした。結果を表5に示す。得られた薄膜圧電共振器は、大きな実効的kt2と高いQ値とを有しており、下部誘電体層24および上部誘電体層26を付加した場合にも、優れた特性の薄膜圧電共振器が得られることがわかる。さらに、製造工程における共振器の破損は抑制され、製造歩留まりは97%と格段に優れている。
4 エアーギャップ(空隙、振動空間)
6 基板
7 絶縁層
8 下部電極
814 外部接続導体
10 上部電極
1014 外部接続導体
12 圧電共振器スタック
14 接続導体
16 フレーム層
16’ 振動領域
17 支持領域
18 下部誘電体層
18’ 下部電極支持部分
20 上部誘電体層
20’ 緩衝領域
22 音響反射層
22’ 空隙領域
24 下部誘電体層
26 上部誘電体層
30 犠牲層エッチング用貫通孔
40 振動領域
41 第1振動領域
42 第2振動領域
43 第3振動領域
46 緩衝領域
48 支持領域
50 膜層
60 フレームのような枠様ゾーン
70 レジスト
104、106 入出力ポート
131、133、135、137 ラダー型フィルタの直列共振素子(直列薄膜圧電共振子)
132、134、136、138 ラダー型フィルタの並列共振素子(並列薄膜圧電共振子)
141、143 ラティス型フィルタの直列共振素子(直列薄膜圧電共振子)
142、144 ラティス型フィルタの並列共振素子(並列薄膜圧電共振子)
Claims (22)
- 基板と、該基板上にあって、圧電層と該圧電層を挟んで互いに対向するように形成された上部電極及び下部電極とを有する圧電共振器スタックと、前記基板と前記圧電共振器スタックとの間に形成された空隙または音響反射層と、を含んでなる薄膜圧電共振器であって、
前記圧電共振器スタックは、該圧電共振器スタックの厚み方向に見て前記上部電極と前記下部電極とが互いに重なる振動領域を有し、
該振動領域は第1振動領域、第2振動領域及び第3振動領域からなり、
前記圧電共振器スタックの厚み方向に見て、前記第1振動領域は最外側に存在し、前記第3振動領域は最内側に存在し且つ前記第1振動領域とは接しておらず、前記第2振動領域は前記第1振動領域と前記第3振動領域との間に介在しており、
前記振動領域の一次厚み縦振動の共振周波数は、前記第1振動領域においてf1であり、前記第3振動領域においてf2であり、ここで前記f1と前記f2とがf1<f2の関係を満たし、前記第2振動領域においては前記第1振動領域に接する外側部分から前記第3振動領域に接する内側部分に向かってf1からf2の間の値をとりながら増加していることを特徴とする薄膜圧電共振器。 - 前記圧電共振器スタックは、前記第1振動領域、前記第2振動領域及び前記第3振動領域において、互いに厚みが異なることを特徴とする、請求項1記載の薄膜圧電共振器。
- 前記圧電共振器スタックは、前記振動領域の外周部において、前記上部電極の上に追加形成されたフレーム層を有することを特徴とする、請求項2記載の薄膜圧電共振器。
- 前記フレーム層は、前記第2振動領域において、前記第1振動領域に接する外側部分から前記第3振動領域に接する内側部分に向かって厚みが減少していることを特徴とする、請求項3記載の薄膜圧電共振器。
- 前記フレーム層は、前記第2振動領域において、スロープ状の上面を持ち、前記基板の上面に対する前記スロープ状上面の角度が60°以下であることを特徴とする、請求項4記載の薄膜圧電共振器。
- 前記フレーム層は、ヤング率が1.0×1011N/m2以上である材質からなることを特徴とする、請求項3乃至5のいずれか一項記載の薄膜圧電共振器。
- 前記フレーム層の材質の音響インピーダンスをZfとし、前記上部電極の材質の音響インピーダンスをZuとした場合に、前記Zfと前記Zuとが0.5Zu<Zf<2Zuの関係を満たすことを特徴とする、請求項3乃至6のいずれか一項記載の薄膜圧電共振器。
- 前記上部電極または前記下部電極は、前記第2振動領域において、前記第1振動領域に接する外側部分から前記第3振動領域に接する内側部分に向かって厚みが減少していることを特徴とする、請求項2記載の薄膜圧電共振器。
- 前記上部電極または前記下部電極は、前記第2振動領域において、スロープ状の上面を持ち、前記基板の上面に対する前記スロープ状上面の角度が60°以下であることを特徴とする、請求項8記載の薄膜圧電共振器。
- 前記上部電極または前記下部電極は、ヤング率が1.0×1011N/m2以上である材質からなることを特徴とする、請求項1、2、8及び9のいずれか一項記載の薄膜圧電共振器。
- 前記第1振動領域は、幅が3μm以下であることを特徴とする、請求項1乃至10のいずれか一項記載の薄膜圧電共振器。
- 前記圧電層は窒化アルミニウムからなることを特徴とする、請求項1乃至11のいずれか一項記載の薄膜圧電共振器。
- 前記振動領域は、前記圧電共振器スタックの厚み方向に見て、前記空隙または前記音響反射層の外周縁より内側に存在することを特徴とする、請求項1乃至12いずれか一項記載の薄膜圧電共振器。
- 前記圧電共振器スタックは、前記圧電共振器スタックの厚み方向に見て、前記振動領域の外側に位置する支持領域と、前記振動領域及び前記支持領域の間に位置する緩衝領域と、を更に有し、前記支持領域において前記基板に接していることを特徴とする、請求項1乃至13のいずれか一項記載の薄膜圧電共振器。
- 前記圧電共振器スタックは、前記振動領域の外周部において、前記上部電極の上に追加形成されたフレーム層を有しており、
該フレーム層は、前記第1振動領域、前記緩衝領域及び前記支持領域に亘って厚みが同等であることを特徴とする、請求項14記載の薄膜圧電共振器。 - 前記下部電極は、前記支持領域内において該支持領域と前記緩衝領域との境界に沿って延びる支持部分を有しており、
前記支持部分の幅w1と前記振動領域の圧電共振器スタックの厚みtとが2.17≦w1/t≦10の関係を満たし、前記緩衝領域の幅w2と前記振動領域の圧電共振器スタックの厚みtとが0.25≦w2/t≦2の関係を満たすことを特徴とする、請求項14または15記載の薄膜圧電共振器。 - 前記下部電極の支持部分は、前記圧電共振器スタックの厚み方向に見て、前記上部電極及び該上部電極に接続された外部接続導体の双方と重ならないように形成されていることを特徴とする、請求項16記載の薄膜圧電共振器。
- 前記振動領域の形状は楕円形であることを特徴とする、請求項1乃至17のいずれか一項記載の薄膜圧電共振器。
- 前記楕円の長軸径aと短軸径bとが1<a/b≦1.9の関係を満たすことを特徴とする、請求項18に記載の薄膜圧電共振器。
- 前記圧電共振器スタックは、前記上部電極の上および/又は前記下部電極の下にAlN、AlON、Si3N4およびSiAlONからなる群より選択される少なくとも1つの材質からなる誘電体層を有することを特徴とする、請求項1乃至19のいずれか一項記載の薄膜圧電共振器。
- 請求項1乃至20のいずれか一項記載の薄膜圧電共振器を用いた薄膜圧電フィルタ。
- 直列薄膜圧電共振器と並列薄膜圧電共振器とがラダー型またはラティス型に接続されているラダー型フィルタまたはラティス型フィルタであって、前記並列薄膜圧電共振器にのみ請求項1乃至20のいずれか一項記載の薄膜圧電共振器が用いられている薄膜圧電フィルタ。
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Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120182090A1 (en) * | 2011-01-19 | 2012-07-19 | Wei Pang | Acoustic wave resonator |
US20130147578A1 (en) * | 2010-10-18 | 2013-06-13 | Taiyo Yuden Co., Ltd. | Duplexer |
JP2013123184A (ja) * | 2011-12-12 | 2013-06-20 | Taiyo Yuden Co Ltd | フィルタおよびデュプレクサ |
WO2014087799A1 (ja) * | 2012-12-05 | 2014-06-12 | 株式会社村田製作所 | 圧電部材、弾性波装置及び圧電部材の製造方法 |
JPWO2013175985A1 (ja) * | 2012-05-22 | 2016-01-12 | 株式会社村田製作所 | バルク波共振子 |
JP2016504880A (ja) * | 2013-01-11 | 2016-02-12 | ゼットティーイー コーポレーションZte Corporation | 低挿入損失の圧電音響バンドパスフィルタ及び実現方法 |
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JP2018037906A (ja) * | 2016-08-31 | 2018-03-08 | 太陽誘電株式会社 | 圧電薄膜共振器、フィルタおよびマルチプレクサ。 |
JP2018067902A (ja) * | 2016-10-17 | 2018-04-26 | ウィン セミコンダクターズ コーポレーション | 質量調整構造付きバルク音波共振器およびバルク音波フィルター |
KR101918031B1 (ko) | 2013-01-22 | 2018-11-13 | 삼성전자주식회사 | 스퓨리어스 공진을 감소시키는 공진기 및 공진기 제작 방법 |
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US10756701B2 (en) | 2017-08-17 | 2020-08-25 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave resonator |
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Families Citing this family (76)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8438924B2 (en) * | 2011-02-03 | 2013-05-14 | Inficon, Inc. | Method of determining multilayer thin film deposition on a piezoelectric crystal |
US9577603B2 (en) * | 2011-09-14 | 2017-02-21 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Solidly mounted acoustic resonator having multiple lateral features |
US9608592B2 (en) * | 2014-01-21 | 2017-03-28 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Film bulk acoustic wave resonator (FBAR) having stress-relief |
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US9450565B2 (en) * | 2013-03-12 | 2016-09-20 | Qorvo Us, Inc. | Border ring mode suppression in solidly-mounted bulk acoustic wave resonator |
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US10069472B2 (en) * | 2015-04-10 | 2018-09-04 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave resonator and filter including the same |
US9985194B1 (en) | 2015-05-13 | 2018-05-29 | Qorvo Us, Inc. | Spurious mode suppression in bulk acoustic wave resonator |
US11137250B2 (en) | 2015-10-28 | 2021-10-05 | Georgia Tech Research Corporation | Comb-driven substrate decoupled annulus pitch/roll BAW gyroscope with slanted quadrature tuning electrode |
JP2017103267A (ja) * | 2015-11-30 | 2017-06-08 | セイコーエプソン株式会社 | 圧電素子、圧電素子の形成方法および超音波装置 |
JP6368298B2 (ja) * | 2015-12-14 | 2018-08-01 | 太陽誘電株式会社 | 圧電薄膜共振器、フィルタおよびデュプレクサ |
US10164605B2 (en) * | 2016-01-26 | 2018-12-25 | Avago Technologies International Sales Pte. Limited | Bulk acoustic wave resonator with piezoelectric layer comprising lithium niobate or lithium tantalate |
US10396755B2 (en) | 2016-02-17 | 2019-08-27 | Samsung Electro-Mechanics Co., Ltd. | Resonator having frame and method of manufacturing the same |
KR20170097348A (ko) * | 2016-02-18 | 2017-08-28 | 삼성전기주식회사 | 음향 공진기 및 그 제조 방법 |
US11070184B2 (en) | 2016-03-11 | 2021-07-20 | Akoustis, Inc. | Piezoelectric acoustic resonator manufactured with piezoelectric thin film transfer process |
US11063576B2 (en) | 2016-03-11 | 2021-07-13 | Akoustis, Inc. | Front end module for 5.6 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US11683021B2 (en) | 2016-03-11 | 2023-06-20 | Akoustis, Inc. | 4.5G 3.55-3.7 GHz band bulk acoustic wave resonator RF filter circuit |
US10673513B2 (en) | 2016-03-11 | 2020-06-02 | Akoustis, Inc. | Front end module for 5.2 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US11476825B2 (en) | 2016-03-11 | 2022-10-18 | Akoustis, Inc. | 5.5 GHz Wi-Fi coexistence acoustic wave resonator RF filter circuit |
US11677372B2 (en) | 2016-03-11 | 2023-06-13 | Akoustis, Inc. | Piezoelectric acoustic resonator with dielectric protective layer manufactured with piezoelectric thin film transfer process |
US10217930B1 (en) | 2016-03-11 | 2019-02-26 | Akoustis, Inc. | Method of manufacture for single crystal acoustic resonator devices using micro-vias |
US10110189B2 (en) | 2016-11-02 | 2018-10-23 | Akoustis, Inc. | Structure and method of manufacture for acoustic resonator or filter devices using improved fabrication conditions and perimeter structure modifications |
US11356071B2 (en) | 2016-03-11 | 2022-06-07 | Akoustis, Inc. | Piezoelectric acoustic resonator with improved TCF manufactured with piezoelectric thin film transfer process |
US10979024B2 (en) | 2016-03-11 | 2021-04-13 | Akoustis, Inc. | 5.2 GHz Wi-Fi coexistence acoustic wave resonator RF filter circuit |
US11418169B2 (en) | 2016-03-11 | 2022-08-16 | Akoustis, Inc. | 5G n41 2.6 GHz band acoustic wave resonator RF filter circuit |
US10979023B2 (en) | 2016-03-11 | 2021-04-13 | Akoustis, Inc. | 5.9 GHz c-V2X and DSRC acoustic wave resonator RF filter circuit |
US10979022B2 (en) | 2016-03-11 | 2021-04-13 | Akoustis, Inc. | 5.2 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US11177868B2 (en) | 2016-03-11 | 2021-11-16 | Akoustis, Inc. | Front end module for 6.5 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US11424728B2 (en) | 2016-03-11 | 2022-08-23 | Akoustis, Inc. | Piezoelectric acoustic resonator manufactured with piezoelectric thin film transfer process |
US11736177B2 (en) | 2016-03-11 | 2023-08-22 | Akoustis Inc. | Front end modules for 5.6 GHz and 6.6 GHz Wi-Fi acoustic wave resonator RF filter circuits |
US11451213B2 (en) | 2016-03-11 | 2022-09-20 | Akoustis, Inc. | 5G n79 Wi-Fi acoustic triplexer circuit |
US11558023B2 (en) | 2016-03-11 | 2023-01-17 | Akoustis, Inc. | Method for fabricating an acoustic resonator device |
US10581398B2 (en) | 2016-03-11 | 2020-03-03 | Akoustis, Inc. | Method of manufacture for single crystal acoustic resonator devices using micro-vias |
US10985732B2 (en) | 2016-03-11 | 2021-04-20 | Akoustis, Inc. | 5.6 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US10979026B2 (en) | 2016-03-11 | 2021-04-13 | Akoustis, Inc. | 5.5 GHz Wi-fi 5G coexistence acoustic wave resonator RF filter circuit |
US11689186B2 (en) | 2016-03-11 | 2023-06-27 | Akoustis, Inc. | 5.5 GHz Wi-Fi 5G coexistence acoustic wave resonator RF filter circuit |
US10523180B2 (en) | 2016-03-11 | 2019-12-31 | Akoustis, Inc. | Method and structure for single crystal acoustic resonator devices using thermal recrystallization |
US10979025B2 (en) | 2016-03-11 | 2021-04-13 | Akoustis, Inc. | 5G band n79 acoustic wave resonator RF filter circuit |
US11184079B2 (en) | 2016-03-11 | 2021-11-23 | Akoustis, Inc. | Front end module for 5.5 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US11316496B2 (en) | 2016-03-11 | 2022-04-26 | Akoustis, Inc. | Method and structure for high performance resonance circuit with single crystal piezoelectric capacitor dielectric material |
US11394451B2 (en) | 2016-03-11 | 2022-07-19 | Akoustis, Inc. | Front end module for 6.1 GHz Wi-Fi acoustic wave resonator RF filter circuit |
US20210257993A1 (en) | 2016-03-11 | 2021-08-19 | Akoustis, Inc. | Acoustic wave resonator rf filter circuit device |
US10921123B2 (en) * | 2016-06-07 | 2021-02-16 | Georgia Tech Research Corporation | Pitch/roll annulus gyroscope with slanted quadrature tuning electrodes and related fabrication methods |
US10554191B2 (en) * | 2016-07-14 | 2020-02-04 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave filter device and method for manufacturing the same |
US10756700B2 (en) | 2016-07-14 | 2020-08-25 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave resonator device |
KR20180018149A (ko) * | 2016-08-12 | 2018-02-21 | 삼성전기주식회사 | 체적 음향 공진기 |
US10833646B2 (en) | 2016-10-12 | 2020-11-10 | Samsung Electro-Mechanics Co., Ltd. | Bulk-acoustic wave resonator and method for manufacturing the same |
US10886888B2 (en) * | 2016-10-27 | 2021-01-05 | Avago Technologies International Sales Pte. Limited | Bulk acoustic wave resonator having openings in an active area and a pillar beneath the opening |
US11736088B2 (en) | 2016-11-15 | 2023-08-22 | Global Communication Semiconductors, Llc | Film bulk acoustic resonator with spurious resonance suppression |
US10601391B2 (en) * | 2016-11-15 | 2020-03-24 | Global Communication Semiconductors, Llc. | Film bulk acoustic resonator with spurious resonance suppression |
KR102380843B1 (ko) * | 2016-12-22 | 2022-04-01 | 삼성전기주식회사 | 체적 음향 공진기 및 이를 포함하는 필터 |
US10637435B2 (en) * | 2016-12-22 | 2020-04-28 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave resonator and filter including the same |
US20180183405A1 (en) * | 2016-12-23 | 2018-06-28 | Avago Technologies General Ip (Singapore) Pte. Ltd | Bulk baw resonator having electrically insulating substrate |
KR102345116B1 (ko) | 2017-03-23 | 2021-12-30 | 삼성전기주식회사 | 음향 공진기 및 그 제조방법 |
US10256788B2 (en) * | 2017-03-31 | 2019-04-09 | Avago Technologies International Sales Pte. Limited | Acoustic resonator including extended cavity |
WO2018182682A1 (en) * | 2017-03-31 | 2018-10-04 | Intel Corporation | Spurious mode suppression using metal meshed frame around bulk acoustic wave resonators |
KR102369434B1 (ko) * | 2017-04-19 | 2022-03-03 | 삼성전기주식회사 | 체적 음향 공진기 및 이의 제조방법 |
CN107196619B (zh) * | 2017-05-04 | 2023-05-12 | 杭州左蓝微电子技术有限公司 | 一种薄膜体声波谐振器锲形形状薄膜制备方法及器件 |
US11418168B2 (en) * | 2017-05-30 | 2022-08-16 | Samsung Electro-Mechanics Co., Ltd. | Acoustic resonator and method for manufacturing the same |
US11563417B2 (en) | 2017-11-20 | 2023-01-24 | Samsung Electro-Mechanics Co., Ltd. | Acoustic resonator |
CN110401428B (zh) * | 2018-04-25 | 2023-04-28 | 芯知微(上海)电子科技有限公司 | 薄膜体声波谐振器及其制造方法 |
US11764750B2 (en) | 2018-07-20 | 2023-09-19 | Global Communication Semiconductors, Llc | Support structure for bulk acoustic wave resonator |
JP7278305B2 (ja) * | 2018-11-05 | 2023-05-19 | 京セラ株式会社 | 弾性波装置、分波器および通信装置 |
KR102212376B1 (ko) * | 2018-12-13 | 2021-02-04 | (주)와이솔 | 압전 박막 공진기 |
US11088672B2 (en) * | 2019-01-19 | 2021-08-10 | Qorvo Us, Inc. | Bulk acoustic wave resonators with shaped border rings |
US11817839B2 (en) | 2019-03-28 | 2023-11-14 | Global Communication Semiconductors, Llc | Single-crystal bulk acoustic wave resonator and method of making thereof |
CN112039460B (zh) * | 2019-07-19 | 2022-05-10 | 中芯集成电路(宁波)有限公司 | 薄膜体声波谐振器及其制作方法 |
US11437975B2 (en) * | 2019-09-06 | 2022-09-06 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic resonator and filter device |
US11979134B2 (en) | 2019-10-15 | 2024-05-07 | Global Communication Semiconductors, Llc | Composite piezoelectric film and bulk acoustic resonator incorporating same |
DE112020006886T5 (de) * | 2020-03-13 | 2022-12-29 | Akoustis, Inc. | Drahtloses kommunikationsinfrastruktursystem konfiguriert mit einem einkristallinen piezo-resonator und filterstruktur unter verwendung eines dünnfilm- übertragungsprozesses |
CN111554800B (zh) * | 2020-04-23 | 2022-07-26 | 瑞声声学科技(深圳)有限公司 | 平坦化方法 |
US20220200571A1 (en) * | 2020-12-23 | 2022-06-23 | Skyworks Solutions, Inc. | Bulk acoustic wave resonator having multiple resonant frequencies |
US20220311419A1 (en) * | 2021-03-25 | 2022-09-29 | Skyworks Global Pte. Ltd. | Filters with raised frame bulk acoustic wave devices |
CN113824420A (zh) * | 2021-08-23 | 2021-12-21 | 杭州电子科技大学 | 具有双环形结构电极的单晶薄膜体声波谐振器制备方法 |
CN113839637A (zh) * | 2021-08-26 | 2021-12-24 | 杭州电子科技大学 | 电极带环槽及条状凸起的单晶薄膜体声波谐振器制备方法 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH11340775A (ja) * | 1998-05-26 | 1999-12-10 | Tdk Corp | 圧電振動子 |
JP2005236337A (ja) * | 2001-05-11 | 2005-09-02 | Ube Ind Ltd | 薄膜音響共振器及びその製造方法 |
JP2008182543A (ja) * | 2007-01-25 | 2008-08-07 | Ube Ind Ltd | 薄膜圧電共振器とそれを用いた薄膜圧電フィルタ |
JP2008288819A (ja) * | 2007-05-17 | 2008-11-27 | Fujitsu Media Device Kk | 圧電薄膜共振器およびフィルタ |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FI107660B (fi) | 1999-07-19 | 2001-09-14 | Nokia Mobile Phones Ltd | Resonaattorirakenne |
US6384697B1 (en) | 2000-05-08 | 2002-05-07 | Agilent Technologies, Inc. | Cavity spanning bottom electrode of a substrate-mounted bulk wave acoustic resonator |
KR100542557B1 (ko) * | 2003-09-09 | 2006-01-11 | 삼성전자주식회사 | 박막 공진기와, 박막 공진기의 제조 방법 및 박막공진기를 구비하는 필터 |
JP4024741B2 (ja) * | 2003-10-20 | 2007-12-19 | 富士通メディアデバイス株式会社 | 圧電薄膜共振子及びフィルタ |
TWI365603B (en) | 2004-10-01 | 2012-06-01 | Avago Technologies Wireless Ip | A thin film bulk acoustic resonator with a mass loaded perimeter |
KR100750736B1 (ko) * | 2004-11-10 | 2007-08-22 | 삼성전자주식회사 | 하나의 트리밍 인덕터를 사용하는 필터 |
JP4550658B2 (ja) | 2005-04-28 | 2010-09-22 | 富士通メディアデバイス株式会社 | 圧電薄膜共振器およびフィルタ |
EP1732219B1 (en) * | 2005-06-09 | 2008-03-26 | ETA SA Manufacture Horlogère Suisse | Piezoelectric resonator and assembly comprising the same enclosed in a case |
JP4877966B2 (ja) * | 2006-03-08 | 2012-02-15 | 日本碍子株式会社 | 圧電薄膜デバイス |
EP2003775A4 (en) * | 2006-04-05 | 2011-04-27 | Murata Manufacturing Co | PIEZOELECTRIC RESONATOR AND PIEZOELECTRIC FILTER |
WO2008090651A1 (ja) * | 2007-01-24 | 2008-07-31 | Murata Manufacturing Co., Ltd. | 圧電共振子及び圧電フィルタ |
US7972521B2 (en) * | 2007-03-12 | 2011-07-05 | Semiconductor Components Industries Llc | Method of making reliable wafer level chip scale package semiconductor devices |
JPWO2009013938A1 (ja) * | 2007-07-20 | 2010-09-30 | 株式会社村田製作所 | 圧電共振子及び圧電フィルタ装置 |
-
2010
- 2010-02-17 US US13/202,442 patent/US8854156B2/en active Active
- 2010-02-17 JP JP2011500623A patent/JP5246454B2/ja not_active Expired - Fee Related
- 2010-02-17 WO PCT/JP2010/052336 patent/WO2010095640A1/ja active Application Filing
- 2010-02-17 CN CN201080005639.9A patent/CN102301590B/zh active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH11340775A (ja) * | 1998-05-26 | 1999-12-10 | Tdk Corp | 圧電振動子 |
JP2005236337A (ja) * | 2001-05-11 | 2005-09-02 | Ube Ind Ltd | 薄膜音響共振器及びその製造方法 |
JP2008182543A (ja) * | 2007-01-25 | 2008-08-07 | Ube Ind Ltd | 薄膜圧電共振器とそれを用いた薄膜圧電フィルタ |
JP2008288819A (ja) * | 2007-05-17 | 2008-11-27 | Fujitsu Media Device Kk | 圧電薄膜共振器およびフィルタ |
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Also Published As
Publication number | Publication date |
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JP5246454B2 (ja) | 2013-07-24 |
CN102301590A (zh) | 2011-12-28 |
US8854156B2 (en) | 2014-10-07 |
JPWO2010095640A1 (ja) | 2012-08-23 |
US20110298564A1 (en) | 2011-12-08 |
CN102301590B (zh) | 2014-07-02 |
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