WO2022227928A1 - Single-crystal piezoelectric bulk acoustic resonator and manufacturing method therefor, filter and electronic device - Google Patents

Single-crystal piezoelectric bulk acoustic resonator and manufacturing method therefor, filter and electronic device Download PDF

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Publication number
WO2022227928A1
WO2022227928A1 PCT/CN2022/081880 CN2022081880W WO2022227928A1 WO 2022227928 A1 WO2022227928 A1 WO 2022227928A1 CN 2022081880 W CN2022081880 W CN 2022081880W WO 2022227928 A1 WO2022227928 A1 WO 2022227928A1
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layer
resonator
temperature compensation
electrode
compensation layer
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PCT/CN2022/081880
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French (fr)
Chinese (zh)
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张孟伦
庞慰
刘伯华
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诺思(天津)微系统有限责任公司
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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
    • 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
    • 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

Definitions

  • Embodiments of the present invention relate to the field of semiconductors, and in particular, to a single crystal piezoelectric bulk acoustic resonator and a method for manufacturing the same, a filter having the resonator, and an electronic device.
  • FBAR thin film bulk acoustic resonator
  • the structural main body of the thin film bulk acoustic wave resonator is a "sandwich" structure composed of an electrode-piezoelectric film-electrode, that is, a piezoelectric material is sandwiched between two metal electrode layers.
  • the FBAR uses the inverse piezoelectric effect to convert the input electrical signal into mechanical resonance, and then uses the piezoelectric effect to convert the mechanical resonance into an electrical signal output.
  • the piezoelectric film commonly used in the prior art is the aluminum nitride piezoelectric film.
  • the use of the aluminum nitride piezoelectric film is not conducive to obtaining a large electromechanical coupling coefficient for the resonator.
  • the resonator using the aluminum nitride piezoelectric film has The electromechanical coupling coefficient is less than 8%, and generally in the range of 6-7%.
  • the resonator using the aluminum nitride piezoelectric film cannot meet the requirement.
  • the BAW resonator generally has a negative frequency temperature drift coefficient, and its frequency temperature drift coefficient is about -30ppm/°C to -300ppm/°C.
  • the piezoelectric material and electrode material of the BAW resonator have negative frequency temperature drift. coefficient, which means that the stiffness of these materials decreases with increasing temperature, and that decreasing stiffness decreases the speed of sound.
  • a temperature compensation layer is added to the resonator, but the addition of the temperature compensation layer will reduce the electromechanical coupling coefficient of the resonator.
  • the addition of the temperature compensation layer makes the use of aluminum nitride piezoelectric in the prior art. Layer-fabricated resonators have lower electromechanical coupling coefficients.
  • the bottom-up processing method is mostly used, in which 01 is the base, 02 is the cavity of the acoustic acoustic mirror, 03 is the bottom electrode, and 04 is the bottom electrode. Above the temperature compensation layer, 05 is the piezoelectric layer, 06 is the temperature compensation layer under the top electrode, and 07 is the top electrode.
  • the key step in manufacturing the traditional BAW resonator is to pattern the bottom electrode after sputtering the bottom electrode, and then continue to grow the piezoelectric layer, so that the piezoelectric layer will have an inclined structure 08 at the edge of the electrode.
  • the inclined structure The surface quality is relatively poor, and the quality of the piezoelectric layer film grown on it is also poor; and there is a sudden inflection point on the inclined structure, which makes the film grown on it prone to stress concentration, which ultimately affects the reliability of the resonator.
  • the temperature compensation layer structure is generally processed on the inner side of the electrode.
  • the existence of the temperature compensation layer on the one hand will make the inclined structure larger, and on the other hand, the existence of the inclined structure will also affect the temperature compensation effect of the temperature compensation layer on the resonator, which will eventually lead to an increase in the parasitic mode of the resonator, poor reliability, and temperature compensation.
  • the compensation effect is also not as expected, and it also reduces the electromechanical coupling coefficient of the resonator.
  • the present invention is proposed to alleviate or solve at least one aspect of the above-mentioned problems in the prior art, such as providing a bulk acoustic wave resonator with an electromechanical coupling coefficient of not less than 9%.
  • a bulk acoustic wave resonator wherein the piezoelectric layer of the resonator is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer, and the resonance
  • the electromechanical coupling coefficient of the device is not less than 9%.
  • Embodiments of the present invention also relate to a method for manufacturing a bulk acoustic wave resonator, wherein the electromechanical coupling coefficient of the resonator is not less than 9%, and the method includes the steps of: providing a POI wafer, the POI wafer comprising a substrate, a single crystal piezoelectric layer and an insulating layer disposed between the first side of the single crystal piezoelectric layer and the substrate, wherein the piezoelectric layer is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and removing the substrate and at least a portion of the insulating layer, during the process of removing the substrate, the insulating layer acts as a barrier layer protecting the piezoelectric layer, the at least a portion of the insulating layer is removed to expose the piezoelectric layer, And the insulating layer of the piezoelectric layer corresponding to the effective area of the resonator is removed.
  • Embodiments of the present invention also relate to a filter comprising the resonator described above.
  • Embodiments of the present invention also relate to an electronic device comprising the above-mentioned filter or the above-mentioned resonator.
  • FIG. 1-11 are schematic cross-sectional views of bulk acoustic wave resonators according to different exemplary embodiments of the present invention, respectively;
  • Figures 12 and 13 are schematic top views showing the relationship between the bottom electrode and the temperature compensation layer in Figure 9, respectively, according to different embodiments of the present invention.
  • FIG. 14A-14I are schematic cross-sectional views illustrating a manufacturing process of the bulk acoustic wave resonator shown in FIG. 5 according to an exemplary embodiment of the present invention
  • FIG. 15 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an embodiment of the present invention, wherein the remaining insulating layer is shown between the electrode connection end of the top electrode and the piezoelectric layer;
  • 16 is a schematic cross-sectional view of a bulk acoustic wave resonator according to another embodiment of the present invention, showing the upper surface of the piezoelectric layer with the remaining insulating layer outside the top electrode;
  • 17 is a schematic cross-sectional view of a bulk acoustic wave resonator in the prior art.
  • Substrate the specific material can be silicon, silicon carbide, sapphire, silicon dioxide, or other silicon-based materials.
  • the material may be aluminum nitride, silicon nitride, polysilicon, silicon dioxide, amorphous silicon, boron-doped silicon dioxide, and other silicon-based materials.
  • Acoustic mirror which can be a cavity, or a Bragg reflector and other equivalent forms. Cavities are used in the illustrated embodiment of the present invention.
  • Passivation layer generally a dielectric material, such as silicon dioxide, aluminum nitride, silicon nitride, and the like.
  • Temperature compensation layer the material of the temperature compensation layer is a material opposite to the frequency temperature coefficient of the piezoelectric layer, which can be polysilicon, borophosphate glass (BSG), silicon dioxide (SiO 2 ), fluorine-doped silicon dioxide, Materials such as chromium (Cr) or tellurium oxide (TeO(x)).
  • BSG borophosphate glass
  • SiO 2 silicon dioxide
  • TiO(x) fluorine-doped silicon dioxide
  • Materials such as chromium (Cr) or tellurium oxide (TeO(x)
  • the stiffness of materials with a positive frequency temperature drift coefficient such as SiO 2 will increase as the temperature increases, so it is possible to compensate or reduce ordinary resonance by adding a layer of SiO 2 and other materials with a positive frequency temperature drift coefficient (ie, temperature compensation layer).
  • the speed of sound decreases due to the decrease in stiffness of the temperature compensation layer (excluding the temperature compensation layer) as the temperature rises, so as to reduce the negative drift of the frequency with the increase of temperature, and then zero temperature drift or frequency temperature drift coefficient can be achieved by setting the appropriate thickness of the temperature compensation layer. within ⁇ 5ppm/°C.
  • the material can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or the composite of the above metals or their alloys.
  • a single crystal piezoelectric layer which is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer.
  • Top electrode the material can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or the composite of the above metals or their alloys.
  • the material of the top electrode can be the same or different from the bottom electrode.
  • Bottom electrode electrical connection part the material can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or a composite of the above metals or their alloys.
  • the material of the bottom electrode electrical connection portion may be the same as or different from that of the top electrode.
  • a bridge structure that defines a cavity or gap layer.
  • a cavity or gap layer which is defined by a bridge structure, which can be an air gap, or a vacuum gap, or a non-conductive dielectric layer.
  • the material may be polysilicon, amorphous silicon, silicon dioxide, phosphorus-doped silicon dioxide (PSG), zinc oxide, magnesium oxide, polymer polymers and similar materials.
  • Auxiliary substrate the specific material can be silicon, silicon carbide, sapphire, silicon dioxide, or other silicon-based materials.
  • Insulation layer which plays the role of electrical insulation, such as silicon dioxide.
  • a single crystal piezoelectric layer which is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer.
  • the piezoelectric layer is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate Piezoelectric layer.
  • the single crystal lithium niobate piezoelectric layer or the single crystal lithium tantalate piezoelectric layer is not used in the resonator in the prior art.
  • an efficient manufacturing method can be employed to manufacture a resonator using a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer.
  • the value of the electromechanical coupling coefficient of the resonator using the single crystal lithium niobate piezoelectric layer or the single crystal lithium tantalate piezoelectric layer can be vary on a large scale.
  • the crystal orientation of single crystal lithium niobate or single crystal lithium tantalate can be flexibly selected, which can make the resonator in the It can maintain excellent performance while meeting the design parameters.
  • their crystal orientation is fixed, which limits their flexibility in the design of resonators or filters, which is not conducive to their further development. application and development.
  • the piezoelectric material is single crystal lithium niobate and the crystal orientation is X-cut (X-cut), its temperature drift coefficient is -105ppm/K, and the electromechanical coupling coefficient is 53; when the crystal orientation is Y+163°- When cutting (cutting), its temperature drift coefficient is -60ppm/K, and its electromechanical coupling coefficient is 26, that is, for single crystal lithium niobate, when the selected crystal orientation makes its electromechanical coupling coefficient higher, its temperature drift coefficient is too large, and when the selected crystal orientation makes its temperature drift coefficient low, its electromechanical coupling coefficient is too small.
  • the single crystal lithium niobate piezoelectric resonator can be When the crystal orientation is selected, it can have a high electromechanical coupling coefficient and a low temperature drift coefficient at the same time.
  • choosing to use a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer can make the electromechanical coupling coefficient of the resonator not less than 9%, and further, the electromechanical coupling coefficient of the resonator is not less than 10 %.
  • the BAW resonator shown in FIGS. 1-11 includes a temperature compensation layer 104 .
  • the provision of the temperature compensation layer 104 reduces the electromechanical coupling coefficient of the resonator.
  • the electromechanical coupling coefficient of the resonator will decrease, but its electromechanical coupling coefficient It can still keep not less than 9%, or the electromechanical coupling coefficient of the resonator is not less than 10%, and the existence of the temperature compensation layer can make up for the temperature drift coefficient of the resonator to make it close to or equal to zero, so that the resonator can be kept at a stable frequency The state will not change with the change of the outside temperature.
  • BAW resonators according to different embodiments of the present invention are exemplified one by one with reference to FIGS. 1-11 .
  • a support structure or support layer 101 is provided between the lower surface of the single crystal piezoelectric layer 106 and the upper surface of the substrate 100 , and the piezoelectric layer 106 is arranged substantially parallel to the substrate 100 .
  • the support layer 101 can be used to define the boundaries of the acoustic mirror cavity.
  • the single-crystal piezoelectric layer 106 is flat, and there is no inclined structure, which can avoid the existence of parasitic modes at the inclined structure in the conventional structure, and the poor quality and stress concentration of the grown piezoelectric film Moreover, the piezoelectric layer material is a single crystal material, which can make the piezoelectric loss lower, so as to obtain a higher Q value of the resonator, and at the same time, the electromechanical coupling coefficient and power capacity can be improved.
  • the temperature compensation layer 104 does not cover the inclined structure, the temperature compensation effect of the temperature compensation layer on the resonator is enhanced, while the temperature compensation effect of the conventional structure is deteriorated because the temperature compensation layer covers or is adjacent to the inclined structure.
  • the temperature compensation layer 104 is disposed on the lower side of the bottom electrode 105 , and the end of the temperature compensation layer 104 in the acoustic mirror cavity 102 is substantially aligned with the non-electrode connection end of the bottom electrode in the acoustic mirror cavity 102 flat.
  • a passivation layer 103 is provided, the passivation layer covers the lower side of the entire temperature compensation layer 104 in the cavity of the acoustic mirror, and covers the temperature compensation layer 104 in the cavity of the acoustic mirror. The end within cavity 102 and the non-electrode connection end of the bottom electrode.
  • the passivation layer 103 can protect the temperature compensation layer 104, that is, it can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
  • FIG. 2 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • FIG. 2 is basically the same as FIG. 1 , except that in the embodiment shown in FIG. 2 , the temperature compensation layer 104 is located on the upper side of the top electrode and is covered by the passivation layer 103 , and the passivation layer 103 can play a role in the temperature compensation layer protection.
  • the temperature compensation layer 104 is made of the same material as the sacrificial layer for forming the acoustic mirror cavity of the single crystal thin film acoustic wave resonator, the temperature compensation layer can be protected from being etched during the release process of the sacrificial layer.
  • FIG. 3 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 3 is basically the same as the structure shown in FIG. 1 , the difference is that: in the embodiment shown in FIG. 3 , the temperature compensation layer 104 is located on the upper side of the bottom electrode 105 or located on the bottom electrode 105 and the piezoelectric layer 106 between.
  • the temperature compensation layer 104 in FIG. 3 can be disposed at a position (closer to the piezoelectric layer) with a thinner thickness to achieve the same temperature compensation effect.
  • the end of the temperature compensation layer 104 in the acoustic mirror cavity 102 is substantially flush with the non-electrode connection end of the bottom electrode in the acoustic mirror cavity 102 .
  • a passivation layer 103 is provided, which covers the entire lower side of the bottom electrode 105 in the cavity of the acoustic mirror, and also covers the temperature compensation layer 104 in the cavity of the acoustic mirror. 102 and the non-electrode connection end of the bottom electrode 105 .
  • the passivation layer 103 can play a protective role for the temperature compensation layer 104, that is, it can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
  • FIG. 4 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 4 is basically the same as that shown in FIG. 3 , with one difference: in the embodiment shown in FIG. 4 , the temperature compensation layer 104 located on one side of the cavity of the acoustic mirror is wrapped by the non-electrode connecting end of the bottom electrode 105 , which can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
  • the structure shown in FIG. 4 is basically the same as that shown in FIG. 3 , except that in FIG.
  • the top electrode 107 has a bridge structure 109 and an air gap 110 under the bridge structure 109 .
  • the bridge structure spans the area on the left side of the bottom electrode that does not include the temperature compensation layer, so that in the top view of the resonator, the temperature compensation layer completely covers the effective area of the single crystal thin film acoustic wave resonator D, which maximizes the temperature compensation effect of the single-crystal thin-film acoustic resonator.
  • FIG. 5 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 5 is basically the same as that shown in FIG. 4 , except that in the embodiment shown in FIG. 5 , one end of the temperature compensation layer 104 located in the acoustic mirror cavity 102 is wrapped by the non-electrode connecting end of the bottom electrode 105 and The non-electrode connection end of the bottom electrode is further extended to the left, which can better cover the temperature compensation layer and have a better protection effect on it.
  • FIG. 6 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 6 is basically the same as that shown in FIG. 4, except that in the embodiment shown in FIG.
  • the temperature compensation layer 104 is located on the lower side of the top electrode 107 and is surrounded by the top electrode, and the bridge structure 109 is located on the bottom electrode 105, And spanning the area on the right side of the top electrode 107 without wrapping the temperature compensation layer, this can ensure that in the top view of the resonator, the temperature compensation layer completely covers the effective area D of the single crystal thin film acoustic wave resonator, so that the single crystal thin film acoustic wave resonates The temperature compensation effect of the device is the largest.
  • FIG. 7 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 7 is basically the same as the structure shown in FIG. 3 , the difference is that: in FIG. 7 , the temperature compensation layer 104 is located in the bottom electrode 105 , that is, the upper and lower sides of the temperature compensation layer are both parts of the bottom electrode and are on the right side.
  • the electrode connection ends of the side or bottom electrodes, and the bottom electrode parts on the upper and lower sides of the temperature compensation layer are connected together.
  • the temperature compensation layer can improve the temperature characteristics of the single crystal thin film acoustic wave resonant frequency, it will lead to a significant decrease in the electromechanical coupling coefficient value of the single crystal thin film acoustic wave resonator.
  • a decrease in the value of the electromechanical coupling coefficient results in a narrowing of the passband of the filter composed of the bulk-wave resonator. This is in contrast to many applications requiring wider bandwidth.
  • the temperature compensation layer is mostly composed of high-resistance materials (usually insulating materials)
  • the temperature compensation layer located between the two electrodes of the resonator acts as a series capacitor, and part of the voltage between the two electrodes will fall on the temperature compensation layer, so The voltage drop in the piezoelectric layer is reduced, and the electric field strength in the piezoelectric layer is correspondingly reduced.
  • all the voltage drop is located in the piezoelectric layer, so the electric field in the piezoelectric layer is relatively stronger.
  • the electric field of the temperature compensation layer will weaken the electric field strength in the piezoelectric layer, so it has a great influence on the electromechanical coupling coefficient of the single crystal thin film acoustic wave resonator.
  • the temperature compensation layer 104 is wrapped by the bottom electrode 105 and the bottom electrodes on the upper and lower sides of the temperature compensation layer are connected together on the right side of the temperature compensation layer, the upper and lower surfaces of the temperature compensation layer are connected together. With the same electric potential, there is no electric field at the temperature compensation layer, so the electromechanical coupling coefficient of the resonator can be improved while the temperature stability of the single crystal thin film acoustic wave resonator is improved.
  • a passivation layer 103 is provided in the resonator.
  • the passivation layer 103 covers the bottom electrode 105, the non-electrode connecting end of the bottom electrode and the end of the temperature compensation layer in the acoustic mirror cavity in the acoustic mirror cavity.
  • the passivation layer 103 can play a protective role for the temperature compensation layer 104, that is, it can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
  • FIG. 8 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 8 is basically the same as that shown in FIG. 7 .
  • the temperature compensation layer 104 is completely wrapped by the bottom electrode 105 , that is, the bottom electrodes on the upper and lower sides of the temperature compensation layer are The left and right sides are connected together.
  • a bridge structure 109 is also provided in FIG. 8 , which defines an air gap or gap layer 110 .
  • a passivation layer 3 may also be provided, and the passivation layer 3 covers at least the bottom electrode 105 in the cavity of the acoustic mirror, so as to protect the bottom electrode from being damaged during the release process of the sacrificial material layer forming the cavity of the acoustic mirror. etching.
  • FIG. 9 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 9 is basically the same as that shown in FIG. 7 , except that in the embodiment shown in FIG. 9 , the temperature compensation layer 104 is disconnected, and the disconnected gap is the part of the bottom electrode 105 . In this way, the electric field intensity in the temperature compensation layer can be guaranteed to be zero, and the electromechanical coupling coefficient of the single crystal thin film acoustic wave resonator can be improved.
  • FIG. 10 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 10 is basically the same as that shown in FIG. 7, except that in the embodiment shown in FIG. 10, the temperature compensation layer 104 is located in the top electrode 107, that is, it is surrounded by the top electrode, and the upper and lower sides of the temperature compensation layer are The top electrodes are connected together on the left and right sides.
  • a bridge structure 109 is also provided in FIG. 8 , which defines an air gap or gap layer 110 .
  • FIG. 11 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention.
  • the structure shown in FIG. 11 is basically the same as that shown in FIG. 10 , the difference is that: in the embodiment shown in FIG. 11 , the temperature compensation layer 104 is disconnected, and the disconnected gap is a part of the top electrode 107 . In this way, the electric field intensity in the temperature compensation layer can be guaranteed to be zero, which is beneficial to improve the electromechanical coupling coefficient of the single crystal thin film acoustic wave resonator.
  • FIG. 12 and 13 are schematic top views, respectively, illustrating the relationship between the bottom electrode and the temperature compensation layer of FIG. 9, and showing the communication that electrically connects the upper and lower portions of the bottom electrode to each other, according to different embodiments of the present invention.
  • FIG. 9 may be a cross-sectional view taken along line AA in FIGS. 12 or 13 .
  • a plurality of concentrically arranged continuous split rings are arranged in the temperature compensation layer 104
  • FIG. 13 a plurality of annular array structures are arranged concentrically in the temperature compensation layer 105 .
  • the opening for connecting the bottom electrodes on the upper and lower sides of the temperature compensation layer may be a single annular structure with continuous openings, or a single annular array structure composed of multiple openings.
  • the openings 104A may also be distributed in any shape on the portion of the temperature compensation layer 104 located in the bottom electrode 105 .
  • FIG. 5 The fabrication process of the structure shown in FIG. 5 is exemplarily described below with reference to FIGS. 14A-14I.
  • a bulk acoustic wave resonator is fabricated based on a POI (Piezoelectrics on Insulator, single crystal piezoelectric layer on an insulator) substrate.
  • the POI wafer includes an auxiliary substrate, a single crystal piezoelectric layer, and an insulating layer disposed between the single crystal piezoelectric layer and the auxiliary substrate.
  • the substrate used in this embodiment is a POI substrate, and its structure is shown in FIG. 14A , wherein 112 is a silicon auxiliary substrate, 113 is an insulating layer such as a silicon dioxide layer, and 114 is a single crystal lithium niobate piezoelectric layer.
  • the insulating layer can better protect the single-crystal piezoelectric film (ie, the single-crystal piezoelectric layer), thereby reducing or even avoiding the subsequent removal of the auxiliary substrate.
  • the damage to the single crystal piezoelectric film can be reduced or even avoided to obtain a bulk acoustic wave resonator with excellent performance.
  • the existence of the insulating layer is also conducive to the diversification of the auxiliary substrate removal scheme and simplify the device processing process.
  • Step 1 As shown in FIG. 14B, first deposit a temperature compensation material layer on the POI substrate, and then use dry etching or wet etching to form a pattern to form the temperature compensation layer 104, and then use the same method to form the bottom electrode 105. Other methods of forming the temperature compensation layer 104 and the bottom electrode 105 may also be used.
  • Step 2 As shown in Figure 14C, deposit a layer of sacrificial material film, the sacrificial material can be polysilicon, amorphous silicon, silicon dioxide, doped silicon dioxide and other materials, and then etch by wet or dry method A patterned sacrificial material layer 111 is formed.
  • the layer of sacrificial material corresponds to the cavity of the acoustic mirror.
  • Step 3 As shown in FIG. 14D , a support material layer is deposited on the surfaces of the sacrificial material layer 111 and the bottom electrode 105 , and the support material layer is polished by chemical mechanical polishing (CMP) method to form the support layer 101 .
  • CMP chemical mechanical polishing
  • Step 4 As shown in FIG. 14E, the substrate 100 and the structure shown in FIG. 14D are bonded together by a bonding method.
  • the substrate 100 and the support layer 101 may be physically or chemically bonded through a special bonding layer (not shown), and the material of the bonding layer may be on the substrate 100 or the support layer 101 alone, or on both surfaces.
  • the substrate 100 and the support layer 101 may also be directly bonded without a bonding layer, but a chemical bond may be formed between the substrate 100 and the support layer 101, or the surface may be polished to a very low surface roughness through intermolecular forces. physical bond.
  • Step 5 As shown in FIG. 14F, the structure shown in FIG. 14E is turned over, and the auxiliary substrate 112 and the insulating layer 113 are removed to form the structure shown in FIG. 14F, which is referred to as the piezoelectric single crystal film surface release process.
  • the etching processes of the auxiliary substrate 112 and the insulating layer 113 are very different.
  • the auxiliary substrate 112 is silicon
  • the insulating layer 113 is silicon dioxide.
  • the removal process of the insulating layer 113 is mild, and the damage to the other surface of the piezoelectric single crystal thin film during the process of removing the auxiliary substrate 112 is reduced or even avoided.
  • the surface release process of the piezoelectric single crystal thin film can be realized by removing all the substrate 112 and all the insulating layer 113 .
  • the piezoelectric single crystal thin film surface release process may use a release hole on the substrate 112 first, and then release the material of the insulating layer 113 through the release hole.
  • the process for the overall removal of the substrate 112 or the formation of the release holes may be related processes such as grinding, grinding, polishing, wet or dry etching, laser ablation, or a combination of these processes.
  • the overall removal process of the insulating layer 113 may adopt related processes such as grinding, grinding, polishing, wet or dry etching, laser ablation, or a combination of these processes.
  • the surface of the piezoelectric single crystal film is partially damaged, especially the effective area of the resonator or the filter formed by the resonator is damaged, the surface of the piezoelectric film can be polished through a polishing process.
  • Step 6 As shown in FIG. 14G , the piezoelectric layer 106 and the temperature compensation layer 104 are etched to form through holes, and the connection portion of the bottom electrode 105 is leaked out.
  • Forming vias can be accomplished by wet or dry etching, laser ablation, and other related processes, or a combination of these processes.
  • Step 7 As shown in FIG. 14H , deposit a sacrificial material layer on the single crystal piezoelectric layer 106 and etch to form a bridge sacrificial layer 110A corresponding to the shape of the air gap 110 of the bridge structure 109 .
  • Step 8 As shown in FIG. 14I , deposit and form the top electrode 107 , the bridge structure 109 and the electrode connecting portion 108 of the bottom electrode over the single crystal piezoelectric layer 106 and the bridge sacrificial layer 110A.
  • Step 9 Finally, release the sacrificial layer of the bridge structure and the sacrificial material layer 111 corresponding to the cavity of the acoustic mirror to form the structure shown in FIG. 5 .
  • the present invention also proposes a method for manufacturing a resonator, which includes the steps of: providing a POI wafer, the POI wafer including a substrate, a single crystal piezoelectric layer, and a first side of the single crystal piezoelectric layer.
  • the insulating layer between the substrate and the substrate, the piezoelectric layer is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and removing the substrate and at least a part of the insulating layer, after removing the substrate
  • the insulating layer acts as a barrier layer to protect the piezoelectric layer, the at least a part of the insulating layer is removed to expose the piezoelectric layer, and the insulating layer of the piezoelectric layer corresponding to the effective area of the resonator removed.
  • the insulating layer 113 is completely removed during the surface release process of the piezoelectric single crystal thin film.
  • the present invention is not limited thereto, in other words, in the present invention, only a part of the insulating layer may be removed to expose the 106 or 114 of the piezoelectric layer, and the insulating layer of the piezoelectric layer corresponding to the effective area of the resonator removed.
  • FIG. 15 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an embodiment of the present invention, showing the remaining insulating layer between the electrode connection end of the top electrode and the piezoelectric layer.
  • an insulating layer 113 is provided between the top electrode and the piezoelectric layer.
  • the insulating layer 113 can also cover the surface of the piezoelectric layer at the same time.
  • FIG. 16 is a schematic cross-sectional view of a bulk acoustic wave resonator according to another embodiment of the present invention, showing the upper surface of the piezoelectric layer with the remaining insulating layer outside the top electrode.
  • the insulating layer covers at least part of the surface of the other piezoelectric layers except the top electrode and the bottom electrode connecting portion 108 , so that the piezoelectric layer can also play a protective role.
  • upper and lower are relative to the bottom surface of the base of the resonator.
  • the side close to the bottom surface is the lower side, and the side away from the bottom surface is the upper side.
  • the center of the effective area of the resonator (the overlapping area of the piezoelectric layer, the top electrode, the bottom electrode and the acoustic mirror in the thickness direction of the resonator constitutes the effective area) (ie, the center of the effective area).
  • the side or end of a component close to the center of the effective area is the inner or inner end
  • the side or end of the component away from the center of the effective area is the outer or outer end.
  • BAW resonators may be used to form filters or electronic devices.
  • a bulk acoustic wave resonator wherein:
  • the piezoelectric layer of the resonator is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer;
  • the electromechanical coupling coefficient of the resonator is not less than 9%.
  • the acoustic mirror of the resonator is an acoustic mirror cavity, and the temperature compensation layer is arranged in the bottom electrode;
  • One end of the temperature compensation layer is flush with the non-electrode connection end of the bottom electrode
  • the resonator further includes a protective layer, the protective layer covers the bottom electrode from the lower side of the bottom electrode, and the protective layer covers at least the non-electrode connection end of the bottom electrode and the temperature compensation layer in the cavity of the acoustic mirror. Ends.
  • the electrode on which the temperature compensation layer is located comprises an upper electrode layer and a lower electrode layer respectively located on the upper side and the lower side of the temperature compensation layer, the upper electrode layer or the lower electrode layer electrically connected to each other.
  • thermoelectric layer is provided with a communication part, and the communication part connects the upper electrode layer or the lower electrode layer on the upper and lower sides of the temperature compensation layer of the electrode where the temperature compensation layer is located. electrical connection.
  • the communicating ring includes at least one annular opening, the annular opening being a continuous annularly extending annular opening; or
  • the communication ring includes a plurality of communication holes, and the plurality of communication holes are arranged in at least one annular shape; or
  • the at least one communicating ring includes a plurality of communicating rings arranged concentrically.
  • thermoelectric layer is disposed between the top electrode or the bottom electrode and the piezoelectric layer.
  • the acoustic mirror of the resonator is an acoustic mirror cavity
  • the non-electrode connecting end of the bottom electrode of the resonator covers at least the end of the temperature compensation layer in the cavity of the acoustic mirror.
  • thermoelectric layer is provided on the upper surface of the top electrode, or is provided on the lower surface of the bottom electrode.
  • the temperature compensation layer is arranged on the lower surface of the bottom electrode, the acoustic mirror of the resonator is an acoustic mirror cavity, and the resonator further includes a protective layer, and the protective layer covers the temperature compensation layer from the lower side of the temperature compensation layer. layer, and the protective layer covers at least the non-electrode connection end of the bottom electrode and the end of the temperature compensation layer in the cavity of the acoustic mirror; or
  • the temperature compensation layer is disposed on the upper surface of the temperature compensation layer disposed on the top electrode, and the resonator further includes a protective layer covering at least the upper surface of the temperature compensation layer.
  • a support structure is provided between the lower surface of the piezoelectric layer and the upper surface of the substrate, and the piezoelectric layer and the substrate are arranged substantially parallel to each other;
  • At least a portion of the upper surface of the piezoelectric layer is provided with an insulating layer.
  • a POI wafer is provided, the POI wafer includes a substrate, a single crystal piezoelectric layer, and an insulating layer disposed between the first side of the single crystal piezoelectric layer and the substrate, and the piezoelectric layer is single crystal niobate A lithium piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and
  • the substrate and at least a portion of the insulating layer that acts as a barrier to protect the piezoelectric layer during removal of the substrate the at least a portion of the insulating layer is removed to expose the piezoelectric layer, and The insulating layer of the piezoelectric layer corresponding to the active area of the resonator is removed.
  • the electromechanical coupling coefficient controlling the resonator is not less than 9%.
  • the temperature compensation layer is disposed in a top electrode or a bottom electrode of the resonator.
  • the electrode on which the temperature compensation layer is located includes an upper electrode layer and a lower electrode layer respectively located on the upper side and the lower side of the temperature compensation layer, and the upper electrode layer or the lower electrode layer is electrically connected to each other.
  • the insulating layer remains between the top electrode and the piezoelectric layer in a region corresponding to a portion of the top electrode of the resonator that is outside the effective region.
  • a filter comprising the bulk acoustic wave resonator of any of 1-19.
  • An electronic device comprising the filter according to 24, or the bulk acoustic wave resonator according to any one of 1-19.
  • the electronic equipment here includes but is not limited to intermediate products such as RF front-end, filter and amplifier modules, and terminal products such as mobile phones, WIFI, and drones.

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Abstract

The present invention relates to a bulk acoustic resonator, wherein a piezoelectric layer of the resonator is a single-crystal lithium niobate piezoelectric layer or a single-crystal lithium tantalate piezoelectric layer; and the electromechanical coupling coefficient of the resonator is not less than 9%. The present invention further relates to a manufacturing method for the bulk acoustic resonator. The electromechanical coupling coefficient of the resonator is not less than 9%. The method comprises the steps of: providing a POI wafer, wherein the POI wafer comprises a substrate, a single-crystal piezoelectric layer, and an insulating layer that is arranged between a first side of the single-crystal piezoelectric layer and the substrate, and the piezoelectric layer is a single-crystal lithium niobate piezoelectric layer or a single-crystal lithium tantalate piezoelectric layer; and removing the substrate and at least part of the insulating layer, wherein during the process of removing the substrate, the insulating layer serves as a barrier layer for protecting the piezoelectric layer, the at least part of the insulating layer is removed to expose the piezoelectric layer, and the insulating layer of the piezoelectric layer that corresponds to an effective area of a resonator is removed. The present invention further relates to a filter and an electronic device.

Description

单晶压电体声波谐振器及其制造方法、滤波器及电子设备Single crystal piezoelectric bulk acoustic resonator, method for manufacturing the same, filter and electronic device 技术领域technical field
本发明的实施例涉及半导体领域，尤其涉及一种单晶压电体声波谐振器及其制造方法，一种具有该谐振器的滤波器，以及一种电子设备。Embodiments of the present invention relate to the field of semiconductors, and in particular, to a single crystal piezoelectric bulk acoustic resonator and a method for manufacturing the same, a filter having the resonator, and an electronic device.
背景技术Background technique
随着5G通信技术的日益发展，对通信频段的要求越来越高。传统的射频滤波器受结构和性能的限制，不能满足高频通信的要求。薄膜体声波谐振器(FBAR)作为一种新型的MEMS器件，具有体积小、质量轻、插入损耗低、频带宽以及品质因子高等优点，很好地适应了无线通信系统的更新换代，使FBAR技术成为通信领域的研究热点之一。With the increasing development of 5G communication technology, the requirements for communication frequency bands are getting higher and higher. Traditional RF filters are limited by structure and performance and cannot meet the requirements of high-frequency communication. As a new type of MEMS device, thin film bulk acoustic resonator (FBAR) has the advantages of small size, light weight, low insertion loss, high frequency bandwidth and high quality factor. It has become one of the research hotspots in the field of communication.
薄膜体声波谐振器的结构主体为由电极-压电薄膜-电极组成的“三明治”结构，即两层金属电极层之间夹一层压电材料。通过在两电极间输入正弦信号，FBAR利用逆压电效应将输入电信号转换为机械谐振，并且再利用压电效应将机械谐振转换为电信号输出。The structural main body of the thin film bulk acoustic wave resonator is a "sandwich" structure composed of an electrode-piezoelectric film-electrode, that is, a piezoelectric material is sandwiched between two metal electrode layers. By inputting a sinusoidal signal between two electrodes, the FBAR uses the inverse piezoelectric effect to convert the input electrical signal into mechanical resonance, and then uses the piezoelectric effect to convert the mechanical resonance into an electrical signal output.
在现有技术中常用的压电薄膜为氮化铝压电薄膜，使用氮化铝压电薄膜不利于谐振器获得较大的机电耦合系数，例如使用了氮化铝压电薄膜的谐振器其机电耦合系数小于8％，且一般在6-7％的范围。对于需要较大的机电耦合系数的需求，使用了氮化铝压电薄膜的谐振器并不能满足要求。The piezoelectric film commonly used in the prior art is the aluminum nitride piezoelectric film. The use of the aluminum nitride piezoelectric film is not conducive to obtaining a large electromechanical coupling coefficient for the resonator. For example, the resonator using the aluminum nitride piezoelectric film has The electromechanical coupling coefficient is less than 8%, and generally in the range of 6-7%. For the requirement of a large electromechanical coupling coefficient, the resonator using the aluminum nitride piezoelectric film cannot meet the requirement.
此外，体声波谐振器一般具有负频率温漂系数，其频率温漂系数大概是-30ppm/℃到-300ppm/℃，其原因在于体声波谐振器的压电材料和电极材料是负频率温漂系数，这表示这些材料的刚度会随着温度的升高而减小,刚度降低会使声速下降。基于公式V＝F*λ＝F*2d(其中V为声速，F为频率，λ为波长，d为压电层厚度)，随着声速下降，频率会降低，因此，体声波谐振器存在着随着温度升高而频率漂移的现象。为了减少频率漂移，在谐振器中加入温补层，但是温补层的加入，会导致谐振器的机电耦合系数降低，相应的，温补层的加入使得现有技术中使用氮化铝压电层制作的谐振器机电耦合系数更低。In addition, the BAW resonator generally has a negative frequency temperature drift coefficient, and its frequency temperature drift coefficient is about -30ppm/°C to -300ppm/°C. The reason is that the piezoelectric material and electrode material of the BAW resonator have negative frequency temperature drift. coefficient, which means that the stiffness of these materials decreases with increasing temperature, and that decreasing stiffness decreases the speed of sound. Based on the formula V=F*λ=F*2d (where V is the speed of sound, F is the frequency, λ is the wavelength, and d is the thickness of the piezoelectric layer), as the speed of sound decreases, the frequency will decrease. Therefore, BAW resonators exist The phenomenon of frequency drift with increasing temperature. In order to reduce the frequency drift, a temperature compensation layer is added to the resonator, but the addition of the temperature compensation layer will reduce the electromechanical coupling coefficient of the resonator. Correspondingly, the addition of the temperature compensation layer makes the use of aluminum nitride piezoelectric in the prior art. Layer-fabricated resonators have lower electromechanical coupling coefficients.
另外，在传统薄膜体声波谐振器中，如图17所示，多采用自下而上的加工方式，其中01为基底，02为声声学镜空腔，03为底电极，04为位于底电极之上的温补层，05为压电层，06为位于顶电极之下的温补层，07为顶电极。制造该传统的体声波谐振器的关键步骤是，在溅射底电极后对底电极先进行图形化再继续生长压电层，从而导致压电层在电极边缘处会存在倾斜 结构08，倾斜结构的表面质量比较差，在其上生长的压电层薄膜的质量也较差；而且在倾斜结构上存在突变拐点，导致其上生长的薄膜容易出现应力集中，最终影响谐振器的可靠性。另外，为了弥补谐振器中的温漂，一般会在电极的内侧加工温补层结构。但是温补层的存在一方面会使得倾斜结构变大，另一方面倾斜结构的存在也会影响温补层对谐振器的温补效果，最终导致谐振器寄生模式增多，可靠性变差，温补效果也无法达到预期，而且还会降低谐振器的机电耦合系数。In addition, in the traditional thin-film BAW resonator, as shown in Figure 17, the bottom-up processing method is mostly used, in which 01 is the base, 02 is the cavity of the acoustic acoustic mirror, 03 is the bottom electrode, and 04 is the bottom electrode. Above the temperature compensation layer, 05 is the piezoelectric layer, 06 is the temperature compensation layer under the top electrode, and 07 is the top electrode. The key step in manufacturing the traditional BAW resonator is to pattern the bottom electrode after sputtering the bottom electrode, and then continue to grow the piezoelectric layer, so that the piezoelectric layer will have an inclined structure 08 at the edge of the electrode. The inclined structure The surface quality is relatively poor, and the quality of the piezoelectric layer film grown on it is also poor; and there is a sudden inflection point on the inclined structure, which makes the film grown on it prone to stress concentration, which ultimately affects the reliability of the resonator. In addition, in order to compensate for the temperature drift in the resonator, the temperature compensation layer structure is generally processed on the inner side of the electrode. However, the existence of the temperature compensation layer on the one hand will make the inclined structure larger, and on the other hand, the existence of the inclined structure will also affect the temperature compensation effect of the temperature compensation layer on the resonator, which will eventually lead to an increase in the parasitic mode of the resonator, poor reliability, and temperature compensation. The compensation effect is also not as expected, and it also reduces the electromechanical coupling coefficient of the resonator.
发明内容SUMMARY OF THE INVENTION
为缓解或解决现有技术中的上述问题的至少一个方面，例如提供不小于9％的机电耦合系数的体声波谐振器，提出本发明。The present invention is proposed to alleviate or solve at least one aspect of the above-mentioned problems in the prior art, such as providing a bulk acoustic wave resonator with an electromechanical coupling coefficient of not less than 9%.
根据本发明的实施例的一个方面，提出了一种体声波谐振器，所述谐振器的压电层为单晶铌酸锂压电层或单晶钽酸锂压电层，且所述谐振器的机电耦合系数不小于9％。According to an aspect of the embodiments of the present invention, a bulk acoustic wave resonator is proposed, wherein the piezoelectric layer of the resonator is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer, and the resonance The electromechanical coupling coefficient of the device is not less than 9%.
本发明的实施例还涉及一种体声波谐振器的制造方法，所述谐振器的机电耦合系数不小于9％，所述方法包括步骤：提供POI晶圆，所述POI晶圆包括衬底、单晶压电层以及设置在单晶压电层的第一侧与衬底之间的绝缘层，所述压电层为单晶铌酸锂压电层或单晶钽酸锂压电层；和移除衬底和至少一部分绝缘层，在移除衬底的过程中，所述绝缘层作为保护压电层的阻挡层，所述至少一部分绝缘层被移除以露出所述压电层，且所述压电层的与谐振器的有效区域对应的绝缘层被移除。Embodiments of the present invention also relate to a method for manufacturing a bulk acoustic wave resonator, wherein the electromechanical coupling coefficient of the resonator is not less than 9%, and the method includes the steps of: providing a POI wafer, the POI wafer comprising a substrate, a single crystal piezoelectric layer and an insulating layer disposed between the first side of the single crystal piezoelectric layer and the substrate, wherein the piezoelectric layer is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and removing the substrate and at least a portion of the insulating layer, during the process of removing the substrate, the insulating layer acts as a barrier layer protecting the piezoelectric layer, the at least a portion of the insulating layer is removed to expose the piezoelectric layer, And the insulating layer of the piezoelectric layer corresponding to the effective area of the resonator is removed.
本发明的实施例也涉及一种滤波器，包括上述的谐振器。Embodiments of the present invention also relate to a filter comprising the resonator described above.
本发明的实施例也涉及一种电子设备，包括上述的滤波器或者上述的谐振器。Embodiments of the present invention also relate to an electronic device comprising the above-mentioned filter or the above-mentioned resonator.
附图说明Description of drawings
以下描述与附图可以更好地帮助理解本发明所公布的各种实施例中的这些和其他特点、优点，图中相同的附图标记始终表示相同的部件，其中：These and other features and advantages of the various disclosed embodiments of the present invention may be better understood by the following description and accompanying drawings, in which like reference numerals refer to like parts throughout, wherein:
图1-11分别为根据本发明的不同示例性实施例的体声波谐振器的截面示意图；1-11 are schematic cross-sectional views of bulk acoustic wave resonators according to different exemplary embodiments of the present invention, respectively;
图12和13分别为根据本发明的不同实施例的体现图9中的底电极与 温补层的关系的示意性俯视图；Figures 12 and 13 are schematic top views showing the relationship between the bottom electrode and the temperature compensation layer in Figure 9, respectively, according to different embodiments of the present invention;
图14A-14I为根据本发明的一个示例性实施例的示出图5所示的体声波谐振器的制作过程的截面示意图；14A-14I are schematic cross-sectional views illustrating a manufacturing process of the bulk acoustic wave resonator shown in FIG. 5 according to an exemplary embodiment of the present invention;
图15为根据本发明的一个实施例的体声波谐振器的示意性截面图，其中示出了保留的绝缘层处于顶电极的电极连接端与压电层之间；15 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an embodiment of the present invention, wherein the remaining insulating layer is shown between the electrode connection end of the top electrode and the piezoelectric layer;
图16为根据本发明的另一个实施例的体声波谐振器的示意性截面图，其中示出了保留的绝缘层处于顶电极之外的压电层的上表面；以及16 is a schematic cross-sectional view of a bulk acoustic wave resonator according to another embodiment of the present invention, showing the upper surface of the piezoelectric layer with the remaining insulating layer outside the top electrode; and
图17为现有技术中的体声波谐振器的截面示意图。17 is a schematic cross-sectional view of a bulk acoustic wave resonator in the prior art.
具体实施方式Detailed ways
下面通过实施例，并结合附图，对本发明的技术方案作进一步具体的说明。在说明书中，相同或相似的附图标号指示相同或相似的部件。下述参照附图对本发明实施方式的说明旨在对本发明的总体发明构思进行解释，而不应当理解为对本发明的一种限制。发明的一部分实施例，而并不是全部的实施例。基于本发明中的实施例，本领域普通技术人员所获得的所有其他实施例，都属于本发明保护的范围。The technical solutions of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. In the specification, the same or similar reference numerals refer to the same or similar parts. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the general inventive concept of the present invention, and should not be construed as a limitation of the present invention. Some, but not all, embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art fall within the protection scope of the present invention.
首先，本发明的附图中的附图标记说明如下：First of all, the reference numerals in the accompanying drawings of the present invention are explained as follows:
100：基底，具体材料可选为硅、碳化硅、蓝宝石、二氧化硅、或者其他硅基材料。100: Substrate, the specific material can be silicon, silicon carbide, sapphire, silicon dioxide, or other silicon-based materials.
101：支撑层或支撑材料层，材料可以为氮化铝、氮化硅、多晶硅、二氧化硅、无定形硅、硼掺杂二氧化硅及其他硅基材料等。101 : a support layer or a support material layer, the material may be aluminum nitride, silicon nitride, polysilicon, silicon dioxide, amorphous silicon, boron-doped silicon dioxide, and other silicon-based materials.
102：声学镜，可为空腔，也可采用布拉格反射层及其他等效形式。本发明所示的实施例中采用的是空腔。102: Acoustic mirror, which can be a cavity, or a Bragg reflector and other equivalent forms. Cavities are used in the illustrated embodiment of the present invention.
103：钝化层，一般为介质材料，如二氧化硅、氮化铝、氮化硅等。103: Passivation layer, generally a dielectric material, such as silicon dioxide, aluminum nitride, silicon nitride, and the like.
104：温补层，温补层的材料是与压电层频率温度系数相反的材料，可以为多晶硅、硼磷酸盐玻璃(BSG)、二氧化硅(SiO 2)、氟掺杂二氧化硅、铬(Cr)或碲氧化物(TeO(x))等材料。例如，SiO 2等具有正频率温漂系数材料的刚度会随温度升高而提高，所以可以通过增加SiO 2等具有正频率温漂系数材料层(即温补层)，来补偿或减少普通谐振器(不含温补层)随温度上升刚度下降导致的声速下降，从而减少频率随温度升高而产生的负漂移，进而可以通过设置合适的温补层厚度实现零温漂或频率温漂系数在±5ppm/℃范围内。 104: Temperature compensation layer, the material of the temperature compensation layer is a material opposite to the frequency temperature coefficient of the piezoelectric layer, which can be polysilicon, borophosphate glass (BSG), silicon dioxide (SiO 2 ), fluorine-doped silicon dioxide, Materials such as chromium (Cr) or tellurium oxide (TeO(x)). For example, the stiffness of materials with a positive frequency temperature drift coefficient such as SiO 2 will increase as the temperature increases, so it is possible to compensate or reduce ordinary resonance by adding a layer of SiO 2 and other materials with a positive frequency temperature drift coefficient (ie, temperature compensation layer). The speed of sound decreases due to the decrease in stiffness of the temperature compensation layer (excluding the temperature compensation layer) as the temperature rises, so as to reduce the negative drift of the frequency with the increase of temperature, and then zero temperature drift or frequency temperature drift coefficient can be achieved by setting the appropriate thickness of the temperature compensation layer. within ±5ppm/°C.
105：底电极，材料可选钼、钌、金、铝、镁、钨、铜，钛、铱、锇、 铬或以上金属的复合或其合金等。105: Bottom electrode, the material can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or the composite of the above metals or their alloys.
106：单晶压电层，为单晶铌酸锂压电层或单晶钽酸锂压电层。106: A single crystal piezoelectric layer, which is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer.
107：顶电极，材料可选钼、钌、金、铝、镁、钨、铜，钛、铱、锇、铬或以上金属的复合或其合金等。顶电极的材料可以与底电极相同或不同。107: Top electrode, the material can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or the composite of the above metals or their alloys. The material of the top electrode can be the same or different from the bottom electrode.
108：底电极电连接部，材料可选钼、钌、金、铝、镁、钨、铜，钛、铱、锇、铬或以上金属的复合或其合金等。底电极电连接部的材料可以与顶电极相同，也可以不同。108: Bottom electrode electrical connection part, the material can be selected from molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or a composite of the above metals or their alloys. The material of the bottom electrode electrical connection portion may be the same as or different from that of the top electrode.
109：桥结构，其限定了空腔或间隙层。109: A bridge structure that defines a cavity or gap layer.
110：空腔或间隙层，其由桥结构限定，可以为空气间隙，或者真空间隙，或者不导电介质层。110: A cavity or gap layer, which is defined by a bridge structure, which can be an air gap, or a vacuum gap, or a non-conductive dielectric layer.
110A：桥部牺牲材料层，在制作过程中，用于形成所述空腔。110A: A bridge portion sacrificial material layer used to form the cavity during the fabrication process.
111：牺牲材料层，材料可以是多晶硅、无定形硅、二氧化硅、磷掺杂二氧化硅(PSG)、氧化锌、氧化镁、聚合物高分子及类似材料等。111: a sacrificial material layer, the material may be polysilicon, amorphous silicon, silicon dioxide, phosphorus-doped silicon dioxide (PSG), zinc oxide, magnesium oxide, polymer polymers and similar materials.
112：辅助衬底，具体材料可选为硅、碳化硅、蓝宝石、二氧化硅，或其他硅基材料。112: Auxiliary substrate, the specific material can be silicon, silicon carbide, sapphire, silicon dioxide, or other silicon-based materials.
113：绝缘层，起到电绝缘的作用，例如为二氧化硅。113: Insulation layer, which plays the role of electrical insulation, such as silicon dioxide.
114：单晶压电层，为单晶铌酸锂压电层或单晶钽酸锂压电层。114: A single crystal piezoelectric layer, which is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer.
图1-11分别为根据本发明的不同示例性实施例的体声波谐振器的截面示意图，在这些图示的示例中，压电层为单晶铌酸锂压电层或单晶钽酸锂压电层。1-11 are schematic cross-sectional views of bulk acoustic wave resonators according to different exemplary embodiments of the present invention, respectively. In these illustrated examples, the piezoelectric layer is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate Piezoelectric layer.
基于制造工艺或者制造成本的考虑，在已有的技术中并不在谐振器中使用单晶铌酸锂压电层或单晶钽酸锂压电层。如本发明后面提及的，可以采用有效的制造方法来制造使用单晶铌酸锂压电层或单晶钽酸锂压电层的谐振器。Based on the consideration of the manufacturing process or the manufacturing cost, the single crystal lithium niobate piezoelectric layer or the single crystal lithium tantalate piezoelectric layer is not used in the resonator in the prior art. As mentioned later in the present invention, an efficient manufacturing method can be employed to manufacture a resonator using a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer.
基于单晶铌酸锂压电层或单晶钽酸锂压电层的晶向，使用单晶铌酸锂压电层或单晶钽酸锂压电层的谐振器的机电耦合系数的值可以在较大范围内变化。Based on the crystal orientation of the single crystal lithium niobate piezoelectric layer or the single crystal lithium tantalate piezoelectric layer, the value of the electromechanical coupling coefficient of the resonator using the single crystal lithium niobate piezoelectric layer or the single crystal lithium tantalate piezoelectric layer can be vary on a large scale.
另外对于单晶铌酸锂或单晶钽酸锂，当选用不同晶向作为压电层时，其温漂系数也是不同的，对应的所需温补层的厚度也是不同的，所以可以根据谐振器的设计需求，即根据所需谐振器或滤波器特定的机电耦合系数、频率、温漂等特性，可以灵活选用单晶铌酸锂或单晶钽酸锂的晶向，可以使得谐振器在满足设计参数的同时，能够保持优良的性能。而对于已有技术中的氮化铝压电材料或其他单晶压电材料，由于其晶向是固定的，使得在谐振器或滤波器设计的时候限制了其灵活性，不利于其进一步的应用与发展。In addition, for single crystal lithium niobate or single crystal lithium tantalate, when different crystal orientations are used as piezoelectric layers, the temperature drift coefficients are also different, and the corresponding thickness of the required temperature compensation layer is also different. According to the design requirements of the resonator or filter, that is, according to the specific electromechanical coupling coefficient, frequency, temperature drift and other characteristics of the required resonator or filter, the crystal orientation of single crystal lithium niobate or single crystal lithium tantalate can be flexibly selected, which can make the resonator in the It can maintain excellent performance while meeting the design parameters. For the aluminum nitride piezoelectric materials or other single crystal piezoelectric materials in the prior art, their crystal orientation is fixed, which limits their flexibility in the design of resonators or filters, which is not conducive to their further development. application and development.
例如当压电材料为单晶铌酸锂，晶向为X-cut(X向切割)时，其温漂系数为-105ppm/K，机电耦合系数为53；当晶向为Y+163°-cut(切割)时，其温漂系数为-60ppm/K，机电耦合系数为26，即对于单晶铌酸锂来说，当选择的晶向使其机电耦合系数较高时，其温漂系数就过大，而当选择的晶向使其温漂系数较低时，其机电耦合系数又过小，而在本专利中通过插入温补层，可以使得单晶铌酸锂压电谐振器在晶向的选择时，可以使其具有较高机电耦合系数的同时，又具有较低的温漂系数。For example, when the piezoelectric material is single crystal lithium niobate and the crystal orientation is X-cut (X-cut), its temperature drift coefficient is -105ppm/K, and the electromechanical coupling coefficient is 53; when the crystal orientation is Y+163°- When cutting (cutting), its temperature drift coefficient is -60ppm/K, and its electromechanical coupling coefficient is 26, that is, for single crystal lithium niobate, when the selected crystal orientation makes its electromechanical coupling coefficient higher, its temperature drift coefficient is too large, and when the selected crystal orientation makes its temperature drift coefficient low, its electromechanical coupling coefficient is too small. In this patent, by inserting a temperature compensation layer, the single crystal lithium niobate piezoelectric resonator can be When the crystal orientation is selected, it can have a high electromechanical coupling coefficient and a low temperature drift coefficient at the same time.
在本发明中，选择使用单晶铌酸锂压电层或单晶钽酸锂压电层，可以使得谐振器的机电耦合系数不小于9％，进一步的，谐振器的机电耦合系数不小于10％。In the present invention, choosing to use a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer can make the electromechanical coupling coefficient of the resonator not less than 9%, and further, the electromechanical coupling coefficient of the resonator is not less than 10 %.
如图1-11所示的体声波谐振器包括了温补层104。如之前已经提及的，设置温补层104会降低谐振器的机电耦合系数。但是由于选用的单晶铌酸锂或单晶钽酸锂压电材料本身就具有较高的机电耦合系数，所以加入温补层之后，谐振器的机电耦合系数虽然会下降，但是其机电耦合系数仍能保持不小于9％，或者谐振器的机电耦合系数不小于10％，而且温补层的存在能够弥补谐振器的温漂系数使其接近或者等于零，从而可以使谐振器保持在稳定的频率状态，不会随外界温度的变化而发生改变。The BAW resonator shown in FIGS. 1-11 includes a temperature compensation layer 104 . As already mentioned before, the provision of the temperature compensation layer 104 reduces the electromechanical coupling coefficient of the resonator. However, since the selected single crystal lithium niobate or single crystal lithium tantalate piezoelectric material itself has a high electromechanical coupling coefficient, after adding the temperature compensation layer, the electromechanical coupling coefficient of the resonator will decrease, but its electromechanical coupling coefficient It can still keep not less than 9%, or the electromechanical coupling coefficient of the resonator is not less than 10%, and the existence of the temperature compensation layer can make up for the temperature drift coefficient of the resonator to make it close to or equal to zero, so that the resonator can be kept at a stable frequency The state will not change with the change of the outside temperature.
下面参照附图1-11逐一示例性说明根据本发明的不同实施例的体声波谐振器。BAW resonators according to different embodiments of the present invention are exemplified one by one with reference to FIGS. 1-11 .
如图1所示，单晶压电层106的下表面与基底100的上表面之间设置有支撑结构或支撑层101，压电层106与基底100大体平行布置。支撑层101可以用于限定声学镜空腔的边界。As shown in FIG. 1 , a support structure or support layer 101 is provided between the lower surface of the single crystal piezoelectric layer 106 and the upper surface of the substrate 100 , and the piezoelectric layer 106 is arranged substantially parallel to the substrate 100 . The support layer 101 can be used to define the boundaries of the acoustic mirror cavity.
图1所示的实施例中，单晶压电层106为平直的，不存在倾斜结构，这可以避免传统结构中在倾斜结构处存在寄生模式、以及生长的压电薄膜质量差和应力集中的问题，而且压电层材料为单晶材料，可以使压电损耗更低，从而得到更高的谐振器Q值，同时可以提高机电耦合系数和功率容量。另一方面，由于温补层104并未覆盖倾斜结构，温补层对谐振器的温补效果增强，而传统结构由于温补层覆盖或紧邻倾斜结构，其温补效果变差。In the embodiment shown in FIG. 1 , the single-crystal piezoelectric layer 106 is flat, and there is no inclined structure, which can avoid the existence of parasitic modes at the inclined structure in the conventional structure, and the poor quality and stress concentration of the grown piezoelectric film Moreover, the piezoelectric layer material is a single crystal material, which can make the piezoelectric loss lower, so as to obtain a higher Q value of the resonator, and at the same time, the electromechanical coupling coefficient and power capacity can be improved. On the other hand, since the temperature compensation layer 104 does not cover the inclined structure, the temperature compensation effect of the temperature compensation layer on the resonator is enhanced, while the temperature compensation effect of the conventional structure is deteriorated because the temperature compensation layer covers or is adjacent to the inclined structure.
如图1所示，温补层104设置在底电极105的下侧，温补层104在声学镜空腔102内的端部与底电极的非电极连接端在声学镜空腔102内大体齐平。在图1所示的实施例中，设置了钝化层103，该钝化层在声学镜空腔中覆盖住整个温补层104的下侧，而且包覆住温补层104在声学镜空腔102内的端部以及底电极的非电极连接端。钝化层103能够起到对温补层104的保护作用，即在形成声学镜空腔的牺牲材料层释放过程中能够保护钝化层不被 刻蚀。As shown in FIG. 1 , the temperature compensation layer 104 is disposed on the lower side of the bottom electrode 105 , and the end of the temperature compensation layer 104 in the acoustic mirror cavity 102 is substantially aligned with the non-electrode connection end of the bottom electrode in the acoustic mirror cavity 102 flat. In the embodiment shown in FIG. 1 , a passivation layer 103 is provided, the passivation layer covers the lower side of the entire temperature compensation layer 104 in the cavity of the acoustic mirror, and covers the temperature compensation layer 104 in the cavity of the acoustic mirror. The end within cavity 102 and the non-electrode connection end of the bottom electrode. The passivation layer 103 can protect the temperature compensation layer 104, that is, it can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
图2为根据本发明的另一个示例性实施例的单晶薄膜声波谐振器的截面示意图。图2与图1基本相同，区别在于：在图2所示的实施例中，温补层104位于顶电极的上侧并被钝化层103覆盖住，钝化层103能够起到对温补层的保护作用。当温补层104所用材料与形成单晶薄膜声波谐振器的声学镜空腔牺牲层的材料一样时，能够保护温补层在牺牲层释放过程中不被刻蚀。2 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. FIG. 2 is basically the same as FIG. 1 , except that in the embodiment shown in FIG. 2 , the temperature compensation layer 104 is located on the upper side of the top electrode and is covered by the passivation layer 103 , and the passivation layer 103 can play a role in the temperature compensation layer protection. When the temperature compensation layer 104 is made of the same material as the sacrificial layer for forming the acoustic mirror cavity of the single crystal thin film acoustic wave resonator, the temperature compensation layer can be protected from being etched during the release process of the sacrificial layer.
图3为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图3所示结构与图1中所示结构基本相同，区别在于：在图3所示的实施例中，温补层104位于底电极105的上侧或者是位于底电极105与压电层106之间。图3中温补层104的设置位置(更靠近压电层)能够具有较薄的厚度就起到相同的温补效果。3 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 3 is basically the same as the structure shown in FIG. 1 , the difference is that: in the embodiment shown in FIG. 3 , the temperature compensation layer 104 is located on the upper side of the bottom electrode 105 or located on the bottom electrode 105 and the piezoelectric layer 106 between. The temperature compensation layer 104 in FIG. 3 can be disposed at a position (closer to the piezoelectric layer) with a thinner thickness to achieve the same temperature compensation effect.
在图3中，温补层104在声学镜空腔102内的端部与底电极的非电极连接端在声学镜空腔102内大体齐平。在图3所示的实施例中，设置了钝化层103，该钝化层在声学镜空腔中覆盖住整个底电极105的下侧，而且包覆住温补层104在声学镜空腔102内的端部以及底电极105的非电极连接端。钝化层103能够起到对温补层104的保护作用，即在形成声学镜空腔的牺牲材料层释放过程中能够保护钝化层不被刻蚀。In FIG. 3 , the end of the temperature compensation layer 104 in the acoustic mirror cavity 102 is substantially flush with the non-electrode connection end of the bottom electrode in the acoustic mirror cavity 102 . In the embodiment shown in FIG. 3 , a passivation layer 103 is provided, which covers the entire lower side of the bottom electrode 105 in the cavity of the acoustic mirror, and also covers the temperature compensation layer 104 in the cavity of the acoustic mirror. 102 and the non-electrode connection end of the bottom electrode 105 . The passivation layer 103 can play a protective role for the temperature compensation layer 104, that is, it can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
图4为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图4所示结构与图3基本相同，区别之一在于：在图4所示的实施例中，位于声学镜空腔中一侧的温补层104被底电极105的非电极连接端包裹住，这能够在形成声学镜空腔的牺牲材料层释放过程中能够保护钝化层不被刻蚀。图4所示结构与图3基本相同，区别之二在于：在图4中，顶电极107具有桥结构109和位于桥结构109下方的空气隙110。在图4所示的实施例中，桥结构跨越底电极左侧不包含温补层的区域，这样能够使得在谐振器的俯视图中，温补层完全涵盖了单晶薄膜声波谐振器的有效区域D，这使得单晶薄膜声波谐振器的温补效果最大。4 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 4 is basically the same as that shown in FIG. 3 , with one difference: in the embodiment shown in FIG. 4 , the temperature compensation layer 104 located on one side of the cavity of the acoustic mirror is wrapped by the non-electrode connecting end of the bottom electrode 105 , which can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror. The structure shown in FIG. 4 is basically the same as that shown in FIG. 3 , except that in FIG. 4 , the top electrode 107 has a bridge structure 109 and an air gap 110 under the bridge structure 109 . In the embodiment shown in FIG. 4 , the bridge structure spans the area on the left side of the bottom electrode that does not include the temperature compensation layer, so that in the top view of the resonator, the temperature compensation layer completely covers the effective area of the single crystal thin film acoustic wave resonator D, which maximizes the temperature compensation effect of the single-crystal thin-film acoustic resonator.
图5为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图5所示结构与图4基本相同，区别在于：在图5所示的实施例中，位于声学镜空腔102中的温补层104的一端被底电极105的非电极连接端包裹住并且底电极的非电极连接端向左进一步延伸，这能够对温补层能够具有更好的覆盖性，对其起到更好的保护效果。5 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 5 is basically the same as that shown in FIG. 4 , except that in the embodiment shown in FIG. 5 , one end of the temperature compensation layer 104 located in the acoustic mirror cavity 102 is wrapped by the non-electrode connecting end of the bottom electrode 105 and The non-electrode connection end of the bottom electrode is further extended to the left, which can better cover the temperature compensation layer and have a better protection effect on it.
图6为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图6所示结构与图4基本相同，区别在于：在图6所示的实施例中，温补层104位于顶电极107的下侧且被顶电极包裹住，桥结构109位于底电 极105，且跨越顶电极107的右侧没有包裹温补层的区域，这样能够保证在谐振器的俯视图中，温补层完全涵盖了单晶薄膜声波谐振器的有效区域D内，使得单晶薄膜声波谐振器的温补效果最大。6 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 6 is basically the same as that shown in FIG. 4, except that in the embodiment shown in FIG. 6, the temperature compensation layer 104 is located on the lower side of the top electrode 107 and is surrounded by the top electrode, and the bridge structure 109 is located on the bottom electrode 105, And spanning the area on the right side of the top electrode 107 without wrapping the temperature compensation layer, this can ensure that in the top view of the resonator, the temperature compensation layer completely covers the effective area D of the single crystal thin film acoustic wave resonator, so that the single crystal thin film acoustic wave resonates The temperature compensation effect of the device is the largest.
图7为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图7所示结构与图3所示结构基本相同，区别在于：在图7中，温补层104位于底电极105之中，即温补层的上下两侧都是底电极的部分且在右侧或底电极的电极连接端，温补层上下两侧的底电极部分是连接在一起的。7 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 7 is basically the same as the structure shown in FIG. 3 , the difference is that: in FIG. 7 , the temperature compensation layer 104 is located in the bottom electrode 105 , that is, the upper and lower sides of the temperature compensation layer are both parts of the bottom electrode and are on the right side. The electrode connection ends of the side or bottom electrodes, and the bottom electrode parts on the upper and lower sides of the temperature compensation layer are connected together.
在图3-图6所示的实施例中，设置温补层虽然可以改善单晶薄膜声波谐振频率的温度特性，但是这会导致单晶薄膜声波谐振器的机电耦合系数值明显减小。机电耦合系数值的减小会导致由体波谐振器构成的滤波器的通带变窄。这与许多应用要求达到较宽带宽的目标相反。因为温补层大部分由高电阻材料(通常是绝缘材料)组成，所以位于谐振器两电极之间的温补层作为一个串联电容，两电极间的部分电压会落在温补层上，因此压电层内的压降减小，压电层内的电场强度也相应减小。在两电极间只有压电层的单晶薄膜声波谐振器中，全部压降都位于压电层之内，因此压电层内的电场相对更强。而设置了温补层后，温补层的电场会减弱压电层内的电场强度，因此对单晶薄膜声波谐振器的机电耦合系数产生很大影响。In the embodiments shown in FIGS. 3-6 , although the temperature compensation layer can improve the temperature characteristics of the single crystal thin film acoustic wave resonant frequency, it will lead to a significant decrease in the electromechanical coupling coefficient value of the single crystal thin film acoustic wave resonator. A decrease in the value of the electromechanical coupling coefficient results in a narrowing of the passband of the filter composed of the bulk-wave resonator. This is in contrast to many applications requiring wider bandwidth. Because the temperature compensation layer is mostly composed of high-resistance materials (usually insulating materials), the temperature compensation layer located between the two electrodes of the resonator acts as a series capacitor, and part of the voltage between the two electrodes will fall on the temperature compensation layer, so The voltage drop in the piezoelectric layer is reduced, and the electric field strength in the piezoelectric layer is correspondingly reduced. In a single crystal thin film acoustic wave resonator with only a piezoelectric layer between the two electrodes, all the voltage drop is located in the piezoelectric layer, so the electric field in the piezoelectric layer is relatively stronger. After the temperature compensation layer is installed, the electric field of the temperature compensation layer will weaken the electric field strength in the piezoelectric layer, so it has a great influence on the electromechanical coupling coefficient of the single crystal thin film acoustic wave resonator.
在图7所示的实施例中，由于温补层104被底电极105包裹并且温补层上下上侧的底电极在温补层的右侧是连接在一起的，因此温补层的上下表面具有相同的电势，所以在温补层处不存在电场，因而可以在提高单晶薄膜声波谐振器的温度稳定性的同时，提高谐振器的机电耦合系数。In the embodiment shown in FIG. 7 , since the temperature compensation layer 104 is wrapped by the bottom electrode 105 and the bottom electrodes on the upper and lower sides of the temperature compensation layer are connected together on the right side of the temperature compensation layer, the upper and lower surfaces of the temperature compensation layer are connected together. With the same electric potential, there is no electric field at the temperature compensation layer, so the electromechanical coupling coefficient of the resonator can be improved while the temperature stability of the single crystal thin film acoustic wave resonator is improved.
如图7所示，谐振器中设置有钝化层103。钝化层103在声学镜空腔内包覆住底电极105以及底电极的非电极连接端和温补层在声学镜空腔内的端部。钝化层103能够起到对温补层104的保护作用，即在形成声学镜空腔的牺牲材料层释放过程中能够保护钝化层不被刻蚀。As shown in FIG. 7 , a passivation layer 103 is provided in the resonator. The passivation layer 103 covers the bottom electrode 105, the non-electrode connecting end of the bottom electrode and the end of the temperature compensation layer in the acoustic mirror cavity in the acoustic mirror cavity. The passivation layer 103 can play a protective role for the temperature compensation layer 104, that is, it can protect the passivation layer from being etched during the release process of the sacrificial material layer forming the cavity of the acoustic mirror.
图8为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图8所示结构与图7基本相同，区别之一在于：在图8所示的实施例中，温补层104完全被底电极105包裹住，即温补层上下两侧的底电极部分在左右两侧是连接在一起。如图8所示，相较于图7，图8中还设置了桥结构109，其限定了空气隙或间隙层110。8 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 8 is basically the same as that shown in FIG. 7 . One of the differences is that in the embodiment shown in FIG. 8 , the temperature compensation layer 104 is completely wrapped by the bottom electrode 105 , that is, the bottom electrodes on the upper and lower sides of the temperature compensation layer are The left and right sides are connected together. As shown in FIG. 8 , compared to FIG. 7 , a bridge structure 109 is also provided in FIG. 8 , which defines an air gap or gap layer 110 .
如图8所示，还可以设置钝化层3，钝化层3在声学镜空腔内至少覆盖底电极105，以在形成声学镜空腔的牺牲材料层释放过程中能够保护底电极不被刻蚀。As shown in FIG. 8 , a passivation layer 3 may also be provided, and the passivation layer 3 covers at least the bottom electrode 105 in the cavity of the acoustic mirror, so as to protect the bottom electrode from being damaged during the release process of the sacrificial material layer forming the cavity of the acoustic mirror. etching.
图9为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示 意图。图9所示结构与图7基本相同，区别在于：在图9所示的实施例中，温补层104是被断开的，在断开的间隙处为底电极105的部分。这样能够保证温补层中的电场强度为零，提高单晶薄膜声波谐振器的机电耦合系数。9 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 9 is basically the same as that shown in FIG. 7 , except that in the embodiment shown in FIG. 9 , the temperature compensation layer 104 is disconnected, and the disconnected gap is the part of the bottom electrode 105 . In this way, the electric field intensity in the temperature compensation layer can be guaranteed to be zero, and the electromechanical coupling coefficient of the single crystal thin film acoustic wave resonator can be improved.
图10为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图10所示结构与图7基本相同，区别在于：在图10所示的实施例中，温补层104位于顶电极107之中，即其被顶电极包裹住，并且温补层上下两侧的顶电极在左右两侧是连接在一起的。如图10所示，相较于图7，图8中还设置了桥结构109，其限定了空气隙或间隙层110。10 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 10 is basically the same as that shown in FIG. 7, except that in the embodiment shown in FIG. 10, the temperature compensation layer 104 is located in the top electrode 107, that is, it is surrounded by the top electrode, and the upper and lower sides of the temperature compensation layer are The top electrodes are connected together on the left and right sides. As shown in FIG. 10 , in comparison to FIG. 7 , a bridge structure 109 is also provided in FIG. 8 , which defines an air gap or gap layer 110 .
图11为根据本发明的另一个示例性实施例单晶薄膜声波谐振器的截面示意图。图11所示结构与图10基本相同，区别在于：在图11所示的实施例中，温补层104是被断开的，在断开的间隙处为顶电极107的部分。这样能够保证温补层中的电场强度为零，有利于提高单晶薄膜声波谐振器的机电耦合系数。11 is a schematic cross-sectional view of a single crystal thin film acoustic wave resonator according to another exemplary embodiment of the present invention. The structure shown in FIG. 11 is basically the same as that shown in FIG. 10 , the difference is that: in the embodiment shown in FIG. 11 , the temperature compensation layer 104 is disconnected, and the disconnected gap is a part of the top electrode 107 . In this way, the electric field intensity in the temperature compensation layer can be guaranteed to be zero, which is beneficial to improve the electromechanical coupling coefficient of the single crystal thin film acoustic wave resonator.
图12和13分别为根据本发明的不同实施例的体现图9中的底电极与温补层的关系的示意性俯视图，且其中示出了使得底电极的上下两个部分彼此电连接的连通部分或开口的结构，图9可以是沿图12或13中的AA线截得的截面图。如图12所示，多个同心布置的连续开口环设置在温补层104中，如图13所示，多个环形阵列结构同心布置在温补层105中。12 and 13 are schematic top views, respectively, illustrating the relationship between the bottom electrode and the temperature compensation layer of FIG. 9, and showing the communication that electrically connects the upper and lower portions of the bottom electrode to each other, according to different embodiments of the present invention. For a partial or open structure, FIG. 9 may be a cross-sectional view taken along line AA in FIGS. 12 or 13 . As shown in FIG. 12 , a plurality of concentrically arranged continuous split rings are arranged in the temperature compensation layer 104 , and as shown in FIG. 13 , a plurality of annular array structures are arranged concentrically in the temperature compensation layer 105 .
虽然没有示出，用于将温补层上下两侧的底电极连接的开口可以是连续开口的单个环形结构，也可以由多个开口组成的单个环形阵列结构。Although not shown, the opening for connecting the bottom electrodes on the upper and lower sides of the temperature compensation layer may be a single annular structure with continuous openings, or a single annular array structure composed of multiple openings.
开口104A也可以在温补层104位于底电极105内的部分上呈任意形状面分布。The openings 104A may also be distributed in any shape on the portion of the temperature compensation layer 104 located in the bottom electrode 105 .
下面参照附图14A-14I示例性说明图5所示结构的制作过程。The fabrication process of the structure shown in FIG. 5 is exemplarily described below with reference to FIGS. 14A-14I.
在本发明中，基于POI(Piezoelectrics on Insulator，绝缘体上的单晶压电层)衬底制作体声波谐振器。POI晶圆包括辅助衬底、单晶压电层以及设置在单晶压电层与辅助衬底之间的绝缘层。本实施例中所用的基底为POI基底，其结构如图14A所示，其中112为硅辅助衬底，113为例如为二氧化硅层的绝缘层，114为单晶铌酸锂压电层。In the present invention, a bulk acoustic wave resonator is fabricated based on a POI (Piezoelectrics on Insulator, single crystal piezoelectric layer on an insulator) substrate. The POI wafer includes an auxiliary substrate, a single crystal piezoelectric layer, and an insulating layer disposed between the single crystal piezoelectric layer and the auxiliary substrate. The substrate used in this embodiment is a POI substrate, and its structure is shown in FIG. 14A , wherein 112 is a silicon auxiliary substrate, 113 is an insulating layer such as a silicon dioxide layer, and 114 is a single crystal lithium niobate piezoelectric layer.
如后面提及的，在谐振器转移加工过程中，绝缘层能够更好的保护单晶压电薄膜(即单晶压电层)，从而可以减小甚至避免后续去除辅助衬底的过程中对单晶压电薄膜的损伤，减小甚至避免对压电薄膜的表面损伤，以得到性能优异的体声波谐振器。As mentioned later, during the resonator transfer process, the insulating layer can better protect the single-crystal piezoelectric film (ie, the single-crystal piezoelectric layer), thereby reducing or even avoiding the subsequent removal of the auxiliary substrate. The damage to the single crystal piezoelectric film can be reduced or even avoided to obtain a bulk acoustic wave resonator with excellent performance.
另外，绝缘层的存在，也有利于辅助衬底去除方案的多样化，简化器件加工工艺。In addition, the existence of the insulating layer is also conducive to the diversification of the auxiliary substrate removal scheme and simplify the device processing process.
步骤1：如图14B所示，先在POI衬底上沉积温补材料层，然后利用干法刻蚀或湿法刻蚀等工艺形成图案以形成温补层104，然后用相同的方法形成底电极105。其他形成温补层104和底电极105的方法也可以使用。Step 1: As shown in FIG. 14B, first deposit a temperature compensation material layer on the POI substrate, and then use dry etching or wet etching to form a pattern to form the temperature compensation layer 104, and then use the same method to form the bottom electrode 105. Other methods of forming the temperature compensation layer 104 and the bottom electrode 105 may also be used.
步骤2：如图14C所示，沉积一层牺牲材料膜层，牺牲材料可以是多晶硅、非晶硅、二氧化硅、掺杂二氧化硅等材料，然后通过湿法或者干法刻蚀的方式形成图案化的牺牲材料层111。牺牲材料层与声学镜空腔对应。Step 2: As shown in Figure 14C, deposit a layer of sacrificial material film, the sacrificial material can be polysilicon, amorphous silicon, silicon dioxide, doped silicon dioxide and other materials, and then etch by wet or dry method A patterned sacrificial material layer 111 is formed. The layer of sacrificial material corresponds to the cavity of the acoustic mirror.
步骤3：如图14D所示，在牺牲材料层111及底电极105的表面沉积形成一层支撑材料层，并通过化学机械研磨(CMP)法将支撑材料层磨平以形成支撑层101。Step 3: As shown in FIG. 14D , a support material layer is deposited on the surfaces of the sacrificial material layer 111 and the bottom electrode 105 , and the support material layer is polished by chemical mechanical polishing (CMP) method to form the support layer 101 .
步骤4：如图14E所示，将基底100与图14D所示结构，通过键合的的方法键合在一起。基底100与支撑层101可以经由专门的键合层(未示出)通过物理或化学方式键合，键合层的材料可单独在基底100或支撑层101上，或二者表面皆有。基底100和支撑层101也可以不经键合层直接键合，而是可以在基底100和支撑层101之间形成化学键，也可以是表面抛光至表面粗糙度极低时通过分子间作用力形成物理键合。Step 4: As shown in FIG. 14E, the substrate 100 and the structure shown in FIG. 14D are bonded together by a bonding method. The substrate 100 and the support layer 101 may be physically or chemically bonded through a special bonding layer (not shown), and the material of the bonding layer may be on the substrate 100 or the support layer 101 alone, or on both surfaces. The substrate 100 and the support layer 101 may also be directly bonded without a bonding layer, but a chemical bond may be formed between the substrate 100 and the support layer 101, or the surface may be polished to a very low surface roughness through intermolecular forces. physical bond.
步骤5：如图14F所示，将图14E所示结构翻转过来，将辅助衬底112以及绝缘层113去除，形成如图14F所示结构，以上称为压电单晶薄膜表面释放工艺。Step 5: As shown in FIG. 14F, the structure shown in FIG. 14E is turned over, and the auxiliary substrate 112 and the insulating layer 113 are removed to form the structure shown in FIG. 14F, which is referred to as the piezoelectric single crystal film surface release process.
辅助衬底112和绝缘层113的刻蚀工艺迥异，比如辅助衬底112是硅，绝缘层113是二氧化硅，绝缘层113可以在辅助衬底112移除过程中起到终止层或阻挡层的作用，绝缘层113的去除工艺温和，减少甚至避免了压电单晶薄膜的另一表面在移除辅助衬底112的过程受到的伤害。The etching processes of the auxiliary substrate 112 and the insulating layer 113 are very different. For example, the auxiliary substrate 112 is silicon, and the insulating layer 113 is silicon dioxide. As a result, the removal process of the insulating layer 113 is mild, and the damage to the other surface of the piezoelectric single crystal thin film during the process of removing the auxiliary substrate 112 is reduced or even avoided.
压电单晶薄膜表面释放工艺可以采用全部去除衬底112、全部去除绝缘层113的方式实现。The surface release process of the piezoelectric single crystal thin film can be realized by removing all the substrate 112 and all the insulating layer 113 .
在可选的实施例中，由于作为阻隔层的绝缘层113的存在，压电单晶薄膜表面释放工艺可以采用在衬底112上先形成释放孔，然后经由该释放孔释放绝缘层113材料。In an optional embodiment, due to the existence of the insulating layer 113 as a barrier layer, the piezoelectric single crystal thin film surface release process may use a release hole on the substrate 112 first, and then release the material of the insulating layer 113 through the release hole.
衬底112的整体去除或者形成释放孔的工艺可以采用磨削、研磨、抛光、湿法或干法刻蚀、激光烧蚀等相关工艺或者这些工艺的集合。The process for the overall removal of the substrate 112 or the formation of the release holes may be related processes such as grinding, grinding, polishing, wet or dry etching, laser ablation, or a combination of these processes.
绝缘层113的整体去除工艺可以采用磨削、研磨、抛光、湿法或干法刻蚀、激光烧蚀等相关工艺或者这些工艺的集合。The overall removal process of the insulating layer 113 may adopt related processes such as grinding, grinding, polishing, wet or dry etching, laser ablation, or a combination of these processes.
绝缘层113去除以后，如果压电单晶薄膜的表面有部分损伤，尤其是谐振器或由谐振器形成的滤波器的有效区域有损伤，可以通过抛光过程对压电薄膜表面进行抛光处理。After the insulating layer 113 is removed, if the surface of the piezoelectric single crystal film is partially damaged, especially the effective area of the resonator or the filter formed by the resonator is damaged, the surface of the piezoelectric film can be polished through a polishing process.
步骤6：如图14G所示，将压电层106和温补层104刻蚀形成通孔，漏出底电极105的连接部分。形成通孔可以通过湿法或干法刻蚀、激光烧蚀等相关工艺或者这些工艺的集合实现。Step 6: As shown in FIG. 14G , the piezoelectric layer 106 and the temperature compensation layer 104 are etched to form through holes, and the connection portion of the bottom electrode 105 is leaked out. Forming vias can be accomplished by wet or dry etching, laser ablation, and other related processes, or a combination of these processes.
步骤7：如图14H所示，在单晶压电层106上方沉积一层牺牲材料层并刻蚀成对应于桥结构109的空气隙110的形状的桥部牺牲层110A。Step 7: As shown in FIG. 14H , deposit a sacrificial material layer on the single crystal piezoelectric layer 106 and etch to form a bridge sacrificial layer 110A corresponding to the shape of the air gap 110 of the bridge structure 109 .
步骤8：如图14I所示，在单晶压电层106和桥部牺牲层110A的上方沉积并形成顶电极107和桥结构109以及底电极的电极连接部分108。Step 8: As shown in FIG. 14I , deposit and form the top electrode 107 , the bridge structure 109 and the electrode connecting portion 108 of the bottom electrode over the single crystal piezoelectric layer 106 and the bridge sacrificial layer 110A.
步骤9：最后将桥结构牺牲层和声学镜空腔对应的牺牲材料层111释放掉，以形成图5所示的结构。Step 9: Finally, release the sacrificial layer of the bridge structure and the sacrificial material layer 111 corresponding to the cavity of the acoustic mirror to form the structure shown in FIG. 5 .
基于以上，本发明也提出了一种谐振器的制造方法，包括步骤：提供POI晶圆，所述POI晶圆包括衬底、单晶压电层以及设置在单晶压电层的第一侧与衬底之间的绝缘层，所述压电层为单晶铌酸锂压电层或单晶钽酸锂压电层；和移除衬底和至少一部分绝缘层，在移除衬底的过程中，所述绝缘层作为保护压电层的阻挡层，所述至少一部分绝缘层被移除以露出所述压电层，且所述压电层的与谐振器的有效区域对应的绝缘层被移除。Based on the above, the present invention also proposes a method for manufacturing a resonator, which includes the steps of: providing a POI wafer, the POI wafer including a substrate, a single crystal piezoelectric layer, and a first side of the single crystal piezoelectric layer. The insulating layer between the substrate and the substrate, the piezoelectric layer is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and removing the substrate and at least a part of the insulating layer, after removing the substrate In the process, the insulating layer acts as a barrier layer to protect the piezoelectric layer, the at least a part of the insulating layer is removed to expose the piezoelectric layer, and the insulating layer of the piezoelectric layer corresponding to the effective area of the resonator removed.
在以上的实施例中，在压电单晶薄膜表面释放工艺中，绝缘层113被完全移除。但是，本发明不限于此，换言之，在本发明中，可以仅仅移除一部分的绝缘层以露出压电层的106或114，且所述压电层的与谐振器的有效区域对应的绝缘层被移除。In the above embodiments, the insulating layer 113 is completely removed during the surface release process of the piezoelectric single crystal thin film. However, the present invention is not limited thereto, in other words, in the present invention, only a part of the insulating layer may be removed to expose the 106 or 114 of the piezoelectric layer, and the insulating layer of the piezoelectric layer corresponding to the effective area of the resonator removed.
图15为根据本发明的一个实施例的体声波谐振器的示意性截面图，其中示出了保留的绝缘层处于顶电极的电极连接端与压电层之间。如图15所示，在谐振器的有效区域之外，在顶电极与压电层之间设置有绝缘层113，绝缘层113如图15所示还可以同时覆盖压电层的表面。15 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an embodiment of the present invention, showing the remaining insulating layer between the electrode connection end of the top electrode and the piezoelectric layer. As shown in FIG. 15 , outside the effective area of the resonator, an insulating layer 113 is provided between the top electrode and the piezoelectric layer. As shown in FIG. 15 , the insulating layer 113 can also cover the surface of the piezoelectric layer at the same time.
图16为根据本发明的另一个实施例的体声波谐振器的示意性截面图，其中示出了保留的绝缘层处于顶电极之外的压电层的上表面。如图16所示，绝缘层覆盖除了顶电极和底电极连接部108覆盖之外的其他压电层的至少部分表面，这样，对于压电层也可以起到保护作用。16 is a schematic cross-sectional view of a bulk acoustic wave resonator according to another embodiment of the present invention, showing the upper surface of the piezoelectric layer with the remaining insulating layer outside the top electrode. As shown in FIG. 16 , the insulating layer covers at least part of the surface of the other piezoelectric layers except the top electrode and the bottom electrode connecting portion 108 , so that the piezoelectric layer can also play a protective role.
在本发明中，上和下是相对于谐振器的基底的底面而言的，对于一个部件，其靠近该底面的一侧为下侧，远离该底面的一侧为上侧。In the present invention, upper and lower are relative to the bottom surface of the base of the resonator. For a component, the side close to the bottom surface is the lower side, and the side away from the bottom surface is the upper side.
在本发明中，内和外是相对于谐振器的有效区域(压电层、顶电极、底电极和声学镜在谐振器的厚度方向上的重叠区域构成有效区域)的中心(即有效区域中心)在横向方向或者径向方向上而言的，一个部件的靠近有效区域中心的一侧或一端为内侧或内端，而该部件的远离有效区域中心的一侧或一端为外侧或外端。对于一个参照位置而言，位于该位置的内侧表示在横向 方向或径向方向上处于该位置与有效区域中心之间，位于该位置的外侧表示在横向方向或径向方向上比该位置更远离有效区域中心。In the present invention, inside and outside are relative to the center of the effective area of the resonator (the overlapping area of the piezoelectric layer, the top electrode, the bottom electrode and the acoustic mirror in the thickness direction of the resonator constitutes the effective area) (ie, the center of the effective area). ) in the transverse or radial direction, the side or end of a component close to the center of the effective area is the inner or inner end, and the side or end of the component away from the center of the effective area is the outer or outer end. For a reference position, being located inside the position means being between the position and the center of the active area in the lateral or radial direction, and being located outside of the position means being farther from the position in the lateral or radial direction than the position Effective regional center.
如本领域技术人员能够理解的，根据本发明的体声波谐振器可以用于形成滤波器或电子设备。As can be appreciated by those skilled in the art, BAW resonators according to the present invention may be used to form filters or electronic devices.
基于以上，本发明提出了如下技术方案：Based on the above, the present invention proposes the following technical solutions:
1、一种体声波谐振器，其中：1. A bulk acoustic wave resonator, wherein:
所述谐振器的压电层为单晶铌酸锂压电层或单晶钽酸锂压电层；且The piezoelectric layer of the resonator is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and
所述谐振器的机电耦合系数不小于9％。The electromechanical coupling coefficient of the resonator is not less than 9%.
2、根据1所述的谐振器，其中，所述谐振器并未设置温补层，且所述谐振器的机电耦合系数不小于10％。2. The resonator according to 1, wherein the resonator is not provided with a temperature compensation layer, and the electromechanical coupling coefficient of the resonator is not less than 10%.
3、根据1所述的谐振器，其中，所述谐振器设置有温补层，且所述谐振器的机电耦合系数不小于9％。3. The resonator according to 1, wherein the resonator is provided with a temperature compensation layer, and the electromechanical coupling coefficient of the resonator is not less than 9%.
4、根据权利3所述的谐振器，其中，所述温补层的至少一部分设置在谐振器的顶电极或底电极中。4. The resonator of claim 3, wherein at least a portion of the temperature compensation layer is disposed in a top electrode or a bottom electrode of the resonator.
5、根据4所述的谐振器，其中，所述温补层整体位于谐振器的顶电极或底电极中，且温补层的端部均被对应电极所包覆。5. The resonator according to 4, wherein the temperature compensation layer is entirely located in the top electrode or the bottom electrode of the resonator, and the ends of the temperature compensation layer are all covered by the corresponding electrodes.
6、根据4所述的谐振器，其中：6. The resonator according to 4, wherein:
所述谐振器的声学镜为声学镜空腔，所述温补层设置在底电极中；The acoustic mirror of the resonator is an acoustic mirror cavity, and the temperature compensation layer is arranged in the bottom electrode;
所述温补层的一端与所述底电极的非电极连接端齐平；以及One end of the temperature compensation layer is flush with the non-electrode connection end of the bottom electrode; and
所述谐振器还包括保护层，所述保护层从底电极的下侧覆盖底电极，且所述保护层在所述声学镜空腔内至少覆盖底电极的非电极连接端以及温补层的端部。The resonator further includes a protective layer, the protective layer covers the bottom electrode from the lower side of the bottom electrode, and the protective layer covers at least the non-electrode connection end of the bottom electrode and the temperature compensation layer in the cavity of the acoustic mirror. Ends.
7、根据4所述的谐振器，其中，所述温补层所在的电极包括分别处于温补层的上侧与下侧的上电极层与下电极层，所述上电极层或下电极层彼此电连接。7. The resonator according to 4, wherein the electrode on which the temperature compensation layer is located comprises an upper electrode layer and a lower electrode layer respectively located on the upper side and the lower side of the temperature compensation layer, the upper electrode layer or the lower electrode layer electrically connected to each other.
8、根据7所述的谐振器，其中，所述温补层设置有连通部，所述连通部将温补层所在的电极的位于温补层的上下两侧的上电极层或下电极层电连接。8. The resonator according to 7, wherein the temperature compensation layer is provided with a communication part, and the communication part connects the upper electrode layer or the lower electrode layer on the upper and lower sides of the temperature compensation layer of the electrode where the temperature compensation layer is located. electrical connection.
9、根据8所述的谐振器，其中，所述连通部包括呈环状布置的至少一个连通环。9. The resonator according to 8, wherein the communicating portion comprises at least one communicating ring arranged in a ring shape.
10、根据9所述的谐振器，其中：10. The resonator according to 9, wherein:
所述连通环包括至少一个环状开口部，所述环状开口部为连续环状延伸的环状开口；或者The communicating ring includes at least one annular opening, the annular opening being a continuous annularly extending annular opening; or
所述连通环包括多个连通孔，所述多个连通孔呈至少一个环状排列；或 者The communication ring includes a plurality of communication holes, and the plurality of communication holes are arranged in at least one annular shape; or
所述至少一个连通环包括同心布置的多个连通环。The at least one communicating ring includes a plurality of communicating rings arranged concentrically.
11、根据7所述的谐振器，其中，所述上电极层或下电极层至少在所述温补层所在电极的电极连接端或者非电极连接端彼此电连接。11. The resonator according to 7, wherein the upper electrode layer or the lower electrode layer is electrically connected to each other at least at the electrode connection end or the non-electrode connection end of the electrode where the temperature compensation layer is located.
12、根据3所述的谐振器，其中，所述温补层设置在顶电极或底电极与压电层之间。12. The resonator according to 3, wherein the temperature compensation layer is disposed between the top electrode or the bottom electrode and the piezoelectric layer.
13、根据12所述的谐振器，其中：13. The resonator of 12, wherein:
所述谐振器的声学镜为声学镜空腔；以及The acoustic mirror of the resonator is an acoustic mirror cavity; and
所述谐振器的底电极的非电极连接端在所述声学镜空腔内至少包覆所述温补层的端部。The non-electrode connecting end of the bottom electrode of the resonator covers at least the end of the temperature compensation layer in the cavity of the acoustic mirror.
14、根据3所述的谐振器，其中，所述温补层设置在顶电极的上表面，或设置在底电极的下表面。14. The resonator according to 3, wherein the temperature compensation layer is provided on the upper surface of the top electrode, or is provided on the lower surface of the bottom electrode.
15、根据14所述的谐振器，其中：15. The resonator of 14, wherein:
所述温补层设置在底电极的下表面，所述谐振器的声学镜为声学镜空腔，且所述谐振器还包括保护层，所述保护层从温补层的下侧覆盖温补层，且所述保护层在所述声学镜空腔内至少覆盖底电极的非电极连接端以及温补层的端部；或者The temperature compensation layer is arranged on the lower surface of the bottom electrode, the acoustic mirror of the resonator is an acoustic mirror cavity, and the resonator further includes a protective layer, and the protective layer covers the temperature compensation layer from the lower side of the temperature compensation layer. layer, and the protective layer covers at least the non-electrode connection end of the bottom electrode and the end of the temperature compensation layer in the cavity of the acoustic mirror; or
所述温补层设置在所述温补层设置在顶电极的上表面，且所述谐振器还包括至少覆盖所述温补层的上表面的保护层。The temperature compensation layer is disposed on the upper surface of the temperature compensation layer disposed on the top electrode, and the resonator further includes a protective layer covering at least the upper surface of the temperature compensation layer.
16、根据3所述的谐振器，其中，所述压电层为平直压电层，且所述温补层与所述压电层的上表面或下表面平行布置。16. The resonator according to 3, wherein the piezoelectric layer is a flat piezoelectric layer, and the temperature compensation layer is arranged in parallel with an upper surface or a lower surface of the piezoelectric layer.
17、根据1-16中任一项所述的谐振器，其中：17. The resonator of any of 1-16, wherein:
压电层的下表面与基底的上表面之间设置有支撑结构，压电层与基底大体平行布置；且A support structure is provided between the lower surface of the piezoelectric layer and the upper surface of the substrate, and the piezoelectric layer and the substrate are arranged substantially parallel to each other; and
在谐振器的有效区域之外，所述压电层的上表面的至少一部分设置有绝缘层。Outside the effective area of the resonator, at least a portion of the upper surface of the piezoelectric layer is provided with an insulating layer.
18、根据17所述的谐振器，其中，在顶电极的处于有效区域之外的部分对应的区域，所述绝缘层至少设置在顶电极的下表面与压电层的上表面之间。18. The resonator according to 17, wherein the insulating layer is disposed at least between the lower surface of the top electrode and the upper surface of the piezoelectric layer in a region corresponding to a portion of the top electrode outside the effective region.
19、根据18所述的谐振器，其中，顶电极的电极连接端的下表面与压电层的上表面之间设置有所述绝缘层。19. The resonator according to 18, wherein the insulating layer is provided between the lower surface of the electrode connection end of the top electrode and the upper surface of the piezoelectric layer.
20、一种体声波谐振器的制造方法，所述谐振器的机电耦合系数不小于9％，所述方法包括步骤：20. A method for manufacturing a bulk acoustic wave resonator, wherein the electromechanical coupling coefficient of the resonator is not less than 9%, the method comprising the steps of:
提供POI晶圆，所述POI晶圆包括衬底、单晶压电层以及设置在单晶压 电层的第一侧与衬底之间的绝缘层，所述压电层为单晶铌酸锂压电层或单晶钽酸锂压电层；和A POI wafer is provided, the POI wafer includes a substrate, a single crystal piezoelectric layer, and an insulating layer disposed between the first side of the single crystal piezoelectric layer and the substrate, and the piezoelectric layer is single crystal niobate A lithium piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and
移除衬底和至少一部分绝缘层，在移除衬底的过程中，所述绝缘层作为保护压电层的阻挡层，所述至少一部分绝缘层被移除以露出所述压电层，且所述压电层的与谐振器的有效区域对应的绝缘层被移除。removing the substrate and at least a portion of the insulating layer that acts as a barrier to protect the piezoelectric layer during removal of the substrate, the at least a portion of the insulating layer is removed to expose the piezoelectric layer, and The insulating layer of the piezoelectric layer corresponding to the active area of the resonator is removed.
21、根据20所述的方法，包括步骤：21. The method according to 20, comprising the steps of:
在所述谐振器中设置温补层；且disposing a temperature compensation layer in the resonator; and
控制所述谐振器的机电耦合系数不小于9％。The electromechanical coupling coefficient controlling the resonator is not less than 9%.
22、根据21所述的方法，其中：22. The method of 21, wherein:
所述温补层的至少一部分设置在谐振器的顶电极或底电极中；且at least a portion of the temperature compensation layer is disposed in a top electrode or a bottom electrode of the resonator; and
所述温补层所在的电极包括分别处于温补层的上侧与下侧的上电极层与下电极层，所述上电极层或下电极层彼此电连接。The electrode on which the temperature compensation layer is located includes an upper electrode layer and a lower electrode layer respectively located on the upper side and the lower side of the temperature compensation layer, and the upper electrode layer or the lower electrode layer is electrically connected to each other.
23、根据21或22所述的方法，其中：23. The method according to 21 or 22, wherein:
移除全部的绝缘层；或者remove all insulation; or
使得在所述谐振器的顶电极的处于有效区域之外的部分对应的区域，在顶电极与压电层之间保留有所述绝缘层。The insulating layer remains between the top electrode and the piezoelectric layer in a region corresponding to a portion of the top electrode of the resonator that is outside the effective region.
24、一种滤波器，包括根据1-19中任一项所述的体声波谐振器。24. A filter comprising the bulk acoustic wave resonator of any of 1-19.
25、一种电子设备，包括根据24所述的滤波器，或者根据1-19中任一项所述的体声波谐振器。25. An electronic device comprising the filter according to 24, or the bulk acoustic wave resonator according to any one of 1-19.
这里的电子设备，包括但不限于射频前端、滤波放大模块等中间产品，以及手机、WIFI、无人机等终端产品。The electronic equipment here includes but is not limited to intermediate products such as RF front-end, filter and amplifier modules, and terminal products such as mobile phones, WIFI, and drones.
尽管已经示出和描述了本发明的实施例，对于本领域的普通技术人员而言，可以理解在不脱离本发明的原理和精神的情况下可以对这些实施例进行变化，本发明的范围由所附权利要求及其等同物限定。Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is determined by It is defined by the appended claims and their equivalents.

Claims (25)

  1. 一种体声波谐振器，其中：A bulk acoustic wave resonator, wherein:
    所述谐振器的压电层为单晶铌酸锂压电层或单晶钽酸锂压电层；且The piezoelectric layer of the resonator is a single crystal lithium niobate piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and
    所述谐振器的机电耦合系数不小于9％。The electromechanical coupling coefficient of the resonator is not less than 9%.
  2. 根据权利要求1所述的谐振器，其中，所述谐振器并未设置温补层，且所述谐振器的机电耦合系数不小于10％。The resonator according to claim 1, wherein the resonator is not provided with a temperature compensation layer, and the electromechanical coupling coefficient of the resonator is not less than 10%.
  3. 根据权利要求1所述的谐振器，其中，所述谐振器设置有温补层，且所述谐振器的机电耦合系数不小于9％。The resonator according to claim 1, wherein the resonator is provided with a temperature compensation layer, and the electromechanical coupling coefficient of the resonator is not less than 9%.
  4. 根据权利3所述的谐振器，其中，所述温补层的至少一部分设置在谐振器的顶电极或底电极中。3. The resonator of claim 3, wherein at least a portion of the temperature compensation layer is disposed in a top electrode or a bottom electrode of the resonator.
  5. 根据权利要求4所述的谐振器，其中，所述温补层整体位于谐振器的顶电极或底电极中，且温补层的端部均被对应电极所包覆。The resonator according to claim 4, wherein the temperature compensation layer is entirely located in the top electrode or the bottom electrode of the resonator, and the ends of the temperature compensation layer are all covered by the corresponding electrodes.
  6. 根据权利要求4所述的谐振器，其中：The resonator of claim 4, wherein:
    所述谐振器的声学镜为声学镜空腔，所述温补层设置在底电极中；The acoustic mirror of the resonator is an acoustic mirror cavity, and the temperature compensation layer is arranged in the bottom electrode;
    所述温补层的一端与所述底电极的非电极连接端齐平；以及One end of the temperature compensation layer is flush with the non-electrode connection end of the bottom electrode; and
    所述谐振器还包括保护层，所述保护层从底电极的下侧覆盖底电极，且所述保护层在所述声学镜空腔内至少覆盖底电极的非电极连接端以及温补层的端部。The resonator further includes a protective layer, the protective layer covers the bottom electrode from the lower side of the bottom electrode, and the protective layer covers at least the non-electrode connection end of the bottom electrode and the temperature compensation layer in the cavity of the acoustic mirror. Ends.
  7. 根据权利要求4所述的谐振器，其中，所述温补层所在的电极包括分别处于温补层的上侧与下侧的上电极层与下电极层，所述上电极层或下电极层彼此电连接。The resonator according to claim 4, wherein the electrode where the temperature compensation layer is located comprises an upper electrode layer and a lower electrode layer respectively located on the upper side and the lower side of the temperature compensation layer, the upper electrode layer or the lower electrode layer electrically connected to each other.
  8. 根据权利要求7所述的谐振器，其中，所述温补层设置有连通部，所述连通部将温补层所在的电极的位于温补层的上下两侧的上电极层或下电极层电连接。The resonator according to claim 7, wherein the temperature compensation layer is provided with a communication part, and the communication part connects the upper electrode layer or the lower electrode layer on the upper and lower sides of the temperature compensation layer of the electrode where the temperature compensation layer is located. electrical connection.
  9. 根据权利要求8所述的谐振器，其中，所述连通部包括呈环状布置的至少一个连通环。9. The resonator of claim 8, wherein the communicating portion includes at least one communicating ring arranged in an annular shape.
  10. 根据权利要求9所述的谐振器，其中：The resonator of claim 9, wherein:
    所述连通环包括至少一个环状开口部，所述环状开口部为连续环状延伸的环状开口；或者The communicating ring includes at least one annular opening, the annular opening being a continuous annularly extending annular opening; or
    所述连通环包括多个连通孔，所述多个连通孔呈至少一个环状排列；或 者The communication ring includes a plurality of communication holes, and the plurality of communication holes are arranged in at least one annular shape; or
    所述至少一个连通环包括同心布置的多个连通环。The at least one communicating ring includes a plurality of communicating rings arranged concentrically.
  11. 根据权利要求7所述的谐振器，其中，所述上电极层或下电极层至少在所述温补层所在电极的电极连接端或者非电极连接端彼此电连接。The resonator according to claim 7, wherein the upper electrode layer or the lower electrode layer is electrically connected to each other at least at the electrode connection end or the non-electrode connection end of the electrode where the temperature compensation layer is located.
  12. 根据权利要求3所述的谐振器，其中，所述温补层设置在顶电极或底电极与压电层之间。The resonator of claim 3, wherein the temperature compensation layer is disposed between the top electrode or the bottom electrode and the piezoelectric layer.
  13. 根据权利要求12所述的谐振器，其中：The resonator of claim 12, wherein:
    所述谐振器的声学镜为声学镜空腔；以及The acoustic mirror of the resonator is an acoustic mirror cavity; and
    所述谐振器的底电极的非电极连接端在所述声学镜空腔内至少包覆所述温补层的端部。The non-electrode connecting end of the bottom electrode of the resonator covers at least the end of the temperature compensation layer in the cavity of the acoustic mirror.
  14. 根据权利要求3所述的谐振器，其中，所述温补层设置在顶电极的上表面，或设置在底电极的下表面。The resonator of claim 3, wherein the temperature compensation layer is provided on the upper surface of the top electrode, or is provided on the lower surface of the bottom electrode.
  15. 根据权利要求14所述的谐振器，其中：The resonator of claim 14, wherein:
    所述温补层设置在底电极的下表面，所述谐振器的声学镜为声学镜空腔，且所述谐振器还包括保护层，所述保护层从温补层的下侧覆盖温补层，且所述保护层在所述声学镜空腔内至少覆盖底电极的非电极连接端以及温补层的端部；或者The temperature compensation layer is arranged on the lower surface of the bottom electrode, the acoustic mirror of the resonator is an acoustic mirror cavity, and the resonator further includes a protective layer, and the protective layer covers the temperature compensation layer from the lower side of the temperature compensation layer. layer, and the protective layer covers at least the non-electrode connection end of the bottom electrode and the end of the temperature compensation layer in the cavity of the acoustic mirror; or
    所述温补层设置在所述温补层设置在顶电极的上表面，且所述谐振器还包括至少覆盖所述温补层的上表面的保护层。The temperature compensation layer is disposed on the upper surface of the temperature compensation layer disposed on the top electrode, and the resonator further includes a protective layer covering at least the upper surface of the temperature compensation layer.
  16. 根据权利要求3所述的谐振器，其中，所述压电层为平直压电层，且所述温补层与所述压电层的上表面或下表面平行布置。The resonator of claim 3, wherein the piezoelectric layer is a flat piezoelectric layer, and the temperature compensation layer is arranged in parallel with an upper surface or a lower surface of the piezoelectric layer.
  17. 根据权利要求1-16中任一项所述的谐振器，其中：The resonator of any of claims 1-16, wherein:
    压电层的下表面与基底的上表面之间设置有支撑结构，压电层与基底大体平行布置；且A support structure is provided between the lower surface of the piezoelectric layer and the upper surface of the substrate, and the piezoelectric layer and the substrate are arranged substantially parallel to each other; and
    在谐振器的有效区域之外，所述压电层的上表面的至少一部分设置有绝缘层。Outside the effective area of the resonator, at least a portion of the upper surface of the piezoelectric layer is provided with an insulating layer.
  18. 根据权利要求17所述的谐振器，其中，在顶电极的处于有效区域之外的部分对应的区域，所述绝缘层至少设置在顶电极的下表面与压电层的上表面之间。The resonator of claim 17, wherein, in a region corresponding to a portion of the top electrode outside the effective region, the insulating layer is provided at least between the lower surface of the top electrode and the upper surface of the piezoelectric layer.
  19. 根据权利要求18所述的谐振器，其中，顶电极的电极连接端的下表面与压电层的上表面之间设置有所述绝缘层。The resonator of claim 18, wherein the insulating layer is provided between the lower surface of the electrode connection end of the top electrode and the upper surface of the piezoelectric layer.
  20. 一种体声波谐振器的制造方法，所述谐振器的机电耦合系数不小于9％，所述方法包括步骤：A method for manufacturing a bulk acoustic wave resonator, wherein the electromechanical coupling coefficient of the resonator is not less than 9%, the method comprising the steps of:
    提供POI晶圆，所述POI晶圆包括衬底、单晶压电层以及设置在单晶压电层的第一侧与衬底之间的绝缘层，所述压电层为单晶铌酸锂压电层或单晶钽酸锂压电层；和A POI wafer is provided, the POI wafer includes a substrate, a single crystal piezoelectric layer, and an insulating layer disposed between the first side of the single crystal piezoelectric layer and the substrate, and the piezoelectric layer is single crystal niobate A lithium piezoelectric layer or a single crystal lithium tantalate piezoelectric layer; and
    移除衬底和至少一部分绝缘层，在移除衬底的过程中，所述绝缘层作为保护压电层的阻挡层，所述至少一部分绝缘层被移除以露出所述压电层，且所述压电层的与谐振器的有效区域对应的绝缘层被移除。removing the substrate and at least a portion of the insulating layer that acts as a barrier to protect the piezoelectric layer during removal of the substrate, the at least a portion of the insulating layer is removed to expose the piezoelectric layer, and The insulating layer of the piezoelectric layer corresponding to the active area of the resonator is removed.
  21. 根据权利要求20所述的方法，包括步骤：The method of claim 20, comprising the steps of:
    在所述谐振器中设置温补层；且disposing a temperature compensation layer in the resonator; and
    控制所述谐振器的机电耦合系数不小于9％。The electromechanical coupling coefficient controlling the resonator is not less than 9%.
  22. 根据权利要求21所述的方法，其中：The method of claim 21, wherein:
    所述温补层的至少一部分设置在谐振器的顶电极或底电极中；且at least a portion of the temperature compensation layer is disposed in a top electrode or a bottom electrode of the resonator; and
    所述温补层所在的电极包括分别处于温补层的上侧与下侧的上电极层与下电极层，所述上电极层或下电极层彼此电连接。The electrode on which the temperature compensation layer is located includes an upper electrode layer and a lower electrode layer respectively located on the upper side and the lower side of the temperature compensation layer, and the upper electrode layer or the lower electrode layer is electrically connected to each other.
  23. 根据权利要求21或22所述的方法，其中：The method of claim 21 or 22, wherein:
    移除全部的绝缘层；或者remove all insulation; or
    使得在所述谐振器的顶电极的处于有效区域之外的部分对应的区域，在顶电极与压电层之间保留有所述绝缘层。The insulating layer remains between the top electrode and the piezoelectric layer in a region corresponding to a portion of the top electrode of the resonator that is outside the effective region.
  24. 一种滤波器，包括根据权利要求1-19中任一项所述的体声波谐振器。19. A filter comprising a bulk acoustic wave resonator according to any one of claims 1-19.
  25. 一种电子设备，包括根据权利要求24所述的滤波器，或者根据权利要求1-19中任一项所述的体声波谐振器。An electronic device comprising a filter according to claim 24, or a bulk acoustic wave resonator according to any one of claims 1-19.
PCT/CN2022/081880 2021-04-27 2022-03-21 Single-crystal piezoelectric bulk acoustic resonator and manufacturing method therefor, filter and electronic device WO2022227928A1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115694409A (en) * 2022-11-10 2023-02-03 武汉敏声新技术有限公司 Resonator packaging structure and method
CN116111966A (en) * 2023-02-09 2023-05-12 上海集成电路材料研究院有限公司 Filter, bulk acoustic wave resonator structure and manufacturing method thereof
CN117156360A (en) * 2023-11-01 2023-12-01 青岛国数信息科技有限公司 Double-insulating-layer annular piezoelectric acoustic chip unit, chip and application
CN117375568A (en) * 2023-12-07 2024-01-09 常州承芯半导体有限公司 Bulk acoustic wave resonator device and method for forming bulk acoustic wave resonator device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106209001A (en) * 2016-06-29 2016-12-07 电子科技大学 FBAR of based single crystal Lithium metaniobate thin slice and preparation method thereof
JP2020014088A (en) * 2018-07-17 2020-01-23 太陽誘電株式会社 Acoustic wave resonator, filter, and multiplexer
CN111049490A (en) * 2019-12-31 2020-04-21 诺思(天津)微系统有限责任公司 Bulk acoustic wave resonator with electrical isolation layer, method of manufacturing the same, filter, and electronic apparatus
CN111919383A (en) * 2018-03-28 2020-11-10 Rf360欧洲有限责任公司 Bulk acoustic wave resonator device and method of manufacturing the same
CN112332797A (en) * 2020-10-29 2021-02-05 广东广纳芯科技有限公司 Lamb wave resonator and method for manufacturing the same
CN112688656A (en) * 2020-12-25 2021-04-20 武汉大学 Two-dimensional high-performance ultrahigh frequency resonator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106209001A (en) * 2016-06-29 2016-12-07 电子科技大学 FBAR of based single crystal Lithium metaniobate thin slice and preparation method thereof
CN111919383A (en) * 2018-03-28 2020-11-10 Rf360欧洲有限责任公司 Bulk acoustic wave resonator device and method of manufacturing the same
JP2020014088A (en) * 2018-07-17 2020-01-23 太陽誘電株式会社 Acoustic wave resonator, filter, and multiplexer
CN111049490A (en) * 2019-12-31 2020-04-21 诺思(天津)微系统有限责任公司 Bulk acoustic wave resonator with electrical isolation layer, method of manufacturing the same, filter, and electronic apparatus
CN112332797A (en) * 2020-10-29 2021-02-05 广东广纳芯科技有限公司 Lamb wave resonator and method for manufacturing the same
CN112688656A (en) * 2020-12-25 2021-04-20 武汉大学 Two-dimensional high-performance ultrahigh frequency resonator

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115694409A (en) * 2022-11-10 2023-02-03 武汉敏声新技术有限公司 Resonator packaging structure and method
CN116111966A (en) * 2023-02-09 2023-05-12 上海集成电路材料研究院有限公司 Filter, bulk acoustic wave resonator structure and manufacturing method thereof
CN116111966B (en) * 2023-02-09 2024-03-29 上海集成电路材料研究院有限公司 Filter, bulk acoustic wave resonator structure and manufacturing method thereof
CN117156360A (en) * 2023-11-01 2023-12-01 青岛国数信息科技有限公司 Double-insulating-layer annular piezoelectric acoustic chip unit, chip and application
CN117156360B (en) * 2023-11-01 2024-03-15 青岛国数信息科技有限公司 Double-insulating-layer annular piezoelectric acoustic chip unit, chip and application
CN117375568A (en) * 2023-12-07 2024-01-09 常州承芯半导体有限公司 Bulk acoustic wave resonator device and method for forming bulk acoustic wave resonator device
CN117375568B (en) * 2023-12-07 2024-03-12 常州承芯半导体有限公司 Bulk acoustic wave resonator device and method for forming bulk acoustic wave resonator device

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