WO2021184863A1 - 一种薄膜体声波谐振器及其制造方法及滤波器、电子设备 - Google Patents

一种薄膜体声波谐振器及其制造方法及滤波器、电子设备 Download PDF

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WO2021184863A1
WO2021184863A1 PCT/CN2020/137049 CN2020137049W WO2021184863A1 WO 2021184863 A1 WO2021184863 A1 WO 2021184863A1 CN 2020137049 W CN2020137049 W CN 2020137049W WO 2021184863 A1 WO2021184863 A1 WO 2021184863A1
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layer
electrode layer
light blocking
etching
manufacturing
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PCT/CN2020/137049
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English (en)
French (fr)
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黄河
罗海龙
李伟
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中芯集成电路（宁波）有限公司
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Publication of WO2021184863A1 publication Critical patent/WO2021184863A1/zh

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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details
    • 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

  • the invention relates to the field of semiconductor device manufacturing, in particular to a thin-film bulk acoustic wave resonator, a manufacturing method thereof, a filter, and electronic equipment.
  • radio frequency front-end modules have gradually become the core components of communication equipment.
  • the filter has become the component with the strongest growth momentum and the greatest development prospects.
  • the performance of the filter is determined by the resonator unit that composes the filter.
  • the film bulk acoustic resonator (FBAR) has the characteristics of small size, low insertion loss, large out-of-band suppression, high quality factor, high operating frequency, large power capacity, and good resistance to electrostatic shock. Become one of the most suitable filters for 5G applications.
  • the thin film bulk acoustic wave resonator includes two thin film electrodes, and a piezoelectric thin film layer is arranged between the two thin film electrodes. Its working principle is to use the piezoelectric thin film layer to generate vibration under an alternating electric field.
  • the bulk acoustic wave propagating in the thickness direction of the electric film layer is transmitted to the interface between the upper and lower electrodes and the air to be reflected back, and then reflected back and forth inside the film to form an oscillation.
  • a standing wave oscillation is formed.
  • the effective resonance area of the thin-film bulk acoustic wave resonator manufactured at present is generally a polygon.
  • the two adjacent sides of the polygon are formed by the side surfaces of the electrode, due to the process, the two sides of the electrode usually form a rounded corner, that is, the angle of the polygon The corners are rounded, which has a greater impact on the performance of the resonator.
  • the electrode is etched, since the electrode metal is in direct contact with the photoresist, during the process of removing the glue, the highly corrosive glue removal solution will more or less damage the electrode, and the etching in different areas The quantity is unstable, and the stability of the final resonator is poor.
  • the purpose of the present invention is to provide a method for manufacturing a thin film bulk acoustic resonator, which solves the problem of rounded corners formed between two adjacent side surfaces of electrodes forming the boundary of the effective resonance region.
  • the present invention provides a method for manufacturing a thin film bulk acoustic resonator, which is characterized in that it includes forming an electrode layer, etching the electrode layer, and the step of etching the electrode layer includes:
  • the light blocking layer can prevent the passage of light, and can be used as a mask layer for patterning the electrode layer;
  • the electrode layer is etched to form at least two side surfaces that serve as the boundary of the effective resonance region in the electrode layer.
  • the adjacent two side surfaces form an included angle.
  • the radius of the arc is less than 1 micron.
  • the present invention also provides a thin film bulk acoustic wave resonator, which is characterized in that it comprises an electrode layer, the electrode layer comprises two adjacent side surfaces, and the adjacent two side surfaces are used as two side surfaces of the effective resonance region boundary.
  • the two adjacent side surfaces enclose an included angle, and the arc radius of the included angle is less than 1 micron.
  • the present invention also provides a filter, which is characterized by comprising a plurality of the above-mentioned resonators.
  • the present invention also provides an electronic device, which is characterized by comprising the above-mentioned filter.
  • the beneficial effect of the present invention is that before the electrode is etched, a light blocking layer is formed on the surface of the electrode, and a photosensitive material layer is formed on the light blocking layer.
  • the light blocking layer has a blocking effect on the light in the electrode and reduces the light entering the electrode Diffraction occurs after the photosensitive material layer, which affects the morphology of the photosensitive material and then the morphology of the electrode.
  • the angle between the two adjacent side surfaces of the electrode forming the boundary of the effective resonator can be sharp, and the radius of the arc of the sharp corner is less than 1 micron, which improves the performance of the resonator.
  • the glue removing solution in the photolithography process does not contact the electrode when removing the photosensitive material layer, and does not damage the electrode, thereby improving the stability of the resonator.
  • first electrode layer, the piezoelectric layer, and the second electrode layer are sequentially deposited on the first substrate.
  • the first electrode layer under the piezoelectric layer has not been etched.
  • the piezoelectric layer is deposited, the The upper surface is flat, thus maintaining the good crystal orientation of the piezoelectric layer.
  • first groove and/or the second groove extend into the piezoelectric layer or penetrate through the piezoelectric layer, so that the leakage of the transverse acoustic wave of the piezoelectric layer is improved, and the quality factor of the resonator is improved.
  • FIGS. 1 to 7 are schematic diagrams of the structure corresponding to the step of etching the electrode layer in the method of manufacturing a thin-film bulk acoustic resonator according to Embodiment 1 of the present invention.
  • FIGS. 8 to 18 are schematic diagrams of corresponding structures in the corresponding steps in the manufacturing method of a thin-film bulk acoustic resonator according to Embodiment 2 of the present invention.
  • Embodiment 1 of the present invention provides a method for manufacturing a thin film bulk acoustic resonator, which is characterized in that it includes forming an electrode layer, etching the electrode layer, and the step of etching the electrode layer includes:
  • the light blocking layer can prevent the passage of light, and can be used as a mask layer for patterning the electrode layer
  • FIG. 1 to 7 are schematic diagrams of the structure corresponding to the step of etching the electrode layer in the method of manufacturing a thin-film bulk acoustic resonator according to Embodiment 1 of the present invention.
  • FIG. 1 to FIG. 7 please refer to FIG. 1 to FIG. 7 to describe in detail the method of etching the electrode layer in this embodiment.
  • an electrode layer 02 is formed on a substrate 01.
  • the substrate 01 can be a single-layer structure or a composite structure.
  • it can be a semiconductor material, such as silicon (Si), germanium (Ge), silicon germanium (SiGe), and silicon carbon (SiC). ), silicon germanium carbon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP) or other III/V compound semiconductors.
  • a cavity may be formed in the substrate 01, the cavity is filled with a sacrificial layer material, the top surface of the sacrificial layer material is flush with the top surface of the substrate, and the electrode layer covers the sacrificial layer material and the substrate.
  • the material of the electrode layer 02 can be a metal material with conductive properties, for example, made of molybdenum (Mo), aluminum (Al), copper (Cu), tungsten (W), tantalum (Ta), platinum (Pt), ruthenium (Ru) ), rhodium (Rh), iridium (Ir), chromium (Cr), titanium (Ti), gold (Au), osmium (Os), rhenium (Re), palladium (Pd) and other metals
  • Mo molybdenum
  • Al aluminum
  • Cu copper
  • tantalum (Ta) platinum
  • Pt platinum
  • Ru ruthenium
  • Rh rhodium
  • Ir iridium
  • Cr chromium
  • Ti titanium
  • gold Au
  • Au osmium
  • Re palladium
  • Pd palladium
  • the above-mentioned metal is made of a laminated layer, and the semiconductor material is, for example
  • step S01 is performed: forming a light blocking layer 03 on the electrode layer 02, the light blocking layer 03 can prevent the passage of light, and can be used as a mask layer for patterning the electrode layer 02.
  • the light blocking layer 03 with a thickness of 1000 angstroms to 1 micron is deposited on the electrode layer 02 by a physical vapor deposition or chemical vapor deposition process.
  • a photoresist is formed on the electrode layer, the photoresist is exposed and developed first, a pattern is formed in the photoresist, and then the photoresist is used as a mask for etching Electrode layer.
  • light irradiates the electrode layer 02 through the photoresist.
  • the material of the electrode layer 02 mostly metal, is reflective, and reflects the light irradiated on the electrode layer into the photoresist.
  • the reflected light exposes the areas where the photoresist does not want to be exposed, so that the shape of the pattern formed in the photoresist is different from the designed shape.
  • the electrode The pattern formed in the layer has also changed as a result, especially when two interfacing surfaces are formed in the electrode layer, the angle formed between the two interfacing surfaces is arc-shaped (it is desirable to form sharp corners without arc-shaped).
  • a light blocking layer 03 is formed on the electrode layer 02 before the photoresist is formed. The light blocking layer 03 can prevent the passage of light and can be used as a mask layer for patterning the electrode layer.
  • the light blocking layer 03 can prevent the light of the electrode layer 02 from entering the photosensitive material layer formed above the light blocking layer in a later process, and on the other hand, it can prevent the light passing through the photosensitive material layer from being reflected back to the photosensitive material layer. . Therefore, the pattern formed in the photosensitive material layer can be consistent with the design. In the later process, the pattern formed in the light blocking layer 03 is consistent with the pattern in the photosensitive material layer, so the pattern formed in the electrode layer 02 can be consistent with the light blocking layer. The patterns formed in 03 are consistent.
  • the arc radius of the included angle between the two adjacent side surfaces of the electrode forming the boundary of the effective resonator can be made smaller than 1 micron, and the performance of the resonator can be improved. In the prior art, half of the arc radius between the two junction surfaces is greater than 2 microns.
  • the material of the light blocking layer 03 includes: amorphous carbon, silicon dioxide, silicon nitride, and silicon oxynitride.
  • step S02 is performed: a photosensitive material layer 04 is formed on the light blocking layer 03.
  • the photosensitive material layer 04 is a photoresist, and the photoresist with a predetermined thickness can be formed on the light blocking layer 03 by a spin coating process.
  • the photosensitive material layer can also be other light-sensitive materials, such as an organic cured film.
  • step S03 is performed: using the photosensitive material layer 04 as a mask, the light blocking layer 03 is etched so that the pattern formed by the light blocking layer 03 is preformed on the electrode layer 02
  • the patterns above are the same.
  • the material of the light blocking layer 03 is amorphous carbon, and etching the light blocking layer 03 includes: after exposing and developing the photosensitive material layer, under an environment with a pressure of 10-30 mTorr, The etching gas uses oxygen and carbon tetrafluoride to etch the light blocking layer.
  • the material of the light blocking layer 03 is silicon dioxide or silicon nitride, and the etching of the light blocking layer includes: exposing and developing the photosensitive material layer, and pressing at a pressure of 50-100 millimeters.
  • the etching gas uses carbon tetrafluoride or octafluorocyclobutane or octafluorocyclopentene to etch the light blocking layer 03.
  • a groove 05 is formed by etching in the light blocking layer 03.
  • the groove 05 includes a first inner side wall 051 and a second inner side wall 052 that are connected to each other. According to the description in step S01, the first inner side wall 051 and the second inner side wall 052 The radius of the arc of the included angle is less than 1 micron.
  • step S04 is performed: using the light blocking layer 03 as a mask, the electrode layer 02 is etched, and at least two side surfaces serving as the boundary of the effective resonance region are formed in the electrode layer 02.
  • the adjacent two side surfaces enclose an included angle, and the arc radius of the included angle is less than 1 micron.
  • the material of the electrode layer 02 is molybdenum
  • etching the electrode layer includes: etching the electrode layer 02 with sulfur fluoride etching gas under an environment with a pressure of 10-50 mtorr.
  • the electrode layer 02 is etched, the light blocking layer 03 is used as a mask, and the first inner sidewall 051 and the second inner sidewall 052 of the groove 05 are etched downward to form the groove 06 in the vertical direction.
  • the first inner side wall 061 of the groove 06 coincides with the first inner side wall 051 of the groove 05
  • the second inner side wall 062 of the groove 06 coincides with the second inner side wall 052 of the groove 05
  • the included angle with the second inner side wall 062 is consistent with the included angle between the first inner side wall 051 and the second inner side wall 052.
  • the first inner side wall 061 and the second inner side wall 062 constitute two side surfaces of the electrode layer, and constitute a partial boundary of the effective resonance region.
  • the sidewalls of the groove may be multiple, for example, 3 sidewalls form a semi-annular shape to form a part of the boundary of the effective resonance region.
  • the method further includes: removing the photosensitive material layer.
  • the material of the photosensitive material layer is photoresist
  • the chemical solution used to remove the photoresist is a weak alkaline solution.
  • the photoresist is formed on the electrode layer. When the photoresist is removed, the solution for removing the photoresist directly contacts the electrode layer, causing damage to the electrode layer.
  • the chemical solution does not contact the electrode layer, and the electrode will not be damaged, which improves the stability of the resonator.
  • the electrode layer 02 after etching the electrode layer 02, it further includes: removing the light blocking layer 02.
  • the light blocking layer 02 is removed by an ashing method, and when the material of the light blocking layer is silicon dioxide, the light blocking layer is removed with a hydrofluoric acid solvent.
  • the bulk acoustic wave resonator includes two electrode layers.
  • the above electrode layer etching process is used for the first electrode layer and the second electrode layer respectively.
  • FIGS. 8 to 18 are a thin film according to Embodiment 2 of the present invention.
  • a second substrate 200 is provided, and a piezoelectric stack structure is formed on the second substrate 200, and the piezoelectric stack structure includes sequentially deposited on the second substrate 200
  • the second electrode layer 204 is etched through the above step of etching the electrode layer, and the at least two side surfaces constitute a partial boundary of the effective resonance region.
  • the first electrode layer, the piezoelectric layer, and the second electrode layer in the effective resonance region are superimposed on each other.
  • the material of the second substrate 200 refers to the material of the aforementioned base, which will not be repeated here.
  • the piezoelectric laminate structure before forming the piezoelectric laminate structure, it further includes forming a release layer 201 on the second substrate 200.
  • the release layer 201 can avoid the pressure of the subsequently formed thin film bulk acoustic resonator. The effect of the electrical stack structure on the second substrate 200.
  • the release layer 201 can be etched to make the second substrate 200 and the subsequently formed The separation of the piezoelectric stack structure helps to quickly remove the second substrate 200 and improve the manufacturing efficiency of the process.
  • the material of the release layer 201 includes but is not limited to at least one of silicon dioxide (SiO2), silicon nitride (Si3N4), aluminum oxide (Al2O3) and aluminum nitride (AlN).
  • the release layer 201 can be formed by chemical vapor deposition, magnetron sputtering, or evaporation.
  • the second substrate 200 is a silicon wafer
  • the material of the release layer 201 is silicon dioxide (SiO2).
  • a first electrode layer 202, a piezoelectric layer 203, and a second electrode layer 204 are sequentially deposited and formed on the second substrate 200.
  • the first electrode layer 202 may be used as an input electrode or an output electrode that receives or provides electrical signals such as radio frequency (RF) signals.
  • RF radio frequency
  • the first electrode layer 202 can be used as an output electrode
  • the second electrode layer 204 is used as an output electrode
  • the first electrode layer 202 can be used as an input electrode.
  • the electrical layer 203 converts electrical signals input through the first electrode layer 202 or the second electrode layer 204 into bulk acoustic waves.
  • the piezoelectric layer 203 converts electrical signals into bulk acoustic waves through physical vibration.
  • the materials of the first electrode layer 202 and the second electrode layer 204 refer to the material of the electrode layer in Embodiment 1.
  • the first electrode layer 202 and the second electrode layer 202 and the second electrode layer 202 can be formed by physical vapor deposition or chemical vapor deposition methods such as magnetron sputtering and evaporation. ⁇ 204 ⁇ Electrode layer 204.
  • the material of the piezoelectric layer 203 can be aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate (PZT), lithium niobate (LiNbO3), quartz (Quartz), potassium niobate (KNbO3) or tantalic acid Piezoelectric materials with wurtzite crystal structure such as lithium (LiTaO3) and their combinations.
  • the piezoelectric layer 104 includes aluminum nitride (AlN)
  • the piezoelectric layer 203 may further include a rare earth metal, such as at least one of scandium (Sc), erbium (Er), yttrium (Y), and lanthanum (La).
  • the piezoelectric layer 203 may further include a transition metal, such as at least one of zirconium (Zr), titanium (Ti), manganese (Mn), and hafnium (Hf). kind.
  • the piezoelectric layer 203 can be deposited by chemical vapor deposition, physical vapor deposition, or atomic layer deposition.
  • the first electrode layer 202, the piezoelectric layer 203, and the second electrode layer 204 are sequentially deposited on the second substrate 200.
  • the first electrode layer 202 under the piezoelectric layer 203 is not etched.
  • the electrical layer 203 is used, the upper surface of the first electrode layer 202 is flat, thereby maintaining the good crystal orientation of the piezoelectric layer 203.
  • the piezoelectric laminate structure after the piezoelectric laminate structure is formed, it further includes forming an etch stop layer 205 on the second electrode layer 204, which may be chemical vapor deposition, physical vapor deposition, or atomic layer deposition.
  • the method deposits and forms an etch stop layer 205.
  • the material of the etch stop layer 205 includes but is not limited to silicon nitride (Si3N4) and silicon oxynitride (SiON).
  • the etch stop layer 205 has a lower etch rate than the support layer formed in the later process.
  • the support layer can be etched to form the cavity 230 to prevent over-etching and protect The surface of the second electrode layer 204 located thereunder is not damaged.
  • the second trench 220 is etched according to the above-mentioned process steps of etching the electrode layer, and the inner sidewall of the second trench 220 constitutes the first At least two sides of the second electrode layer 204.
  • the at least two side surfaces constitute part of the boundary of the effective resonance region.
  • the second trench 220 may also form a plurality of contiguous side surfaces, such as 3 side surfaces, which form a semi-circular shape and form part of the boundary of the effective resonance region.
  • the second trench 220 may extend into the piezoelectric layer 203, may penetrate the entire piezoelectric layer 203, or the bottom surface of the second trench 220 may extend to a set thickness of the piezoelectric layer 203.
  • the second groove 220 penetrates the entire thickness of the piezoelectric layer 203, the effect of preventing lateral acoustic wave leakage is better; when the second groove 220 penetrates a part of the thickness of the piezoelectric layer 203, the structural strength of the resonator is better.
  • it further includes etching the first electrode layer 202.
  • a support layer 206 is formed on the second electrode layer 204;
  • the first electrode layer 202 is etched through the step of etching the electrode layer, and the at least two side surfaces constitute a partial boundary of the effective resonance region.
  • the support layer 206 can be formed by chemical deposition.
  • the material of the support layer 206 can be one of silicon dioxide (SiO2), silicon nitride (Si3N4), aluminum oxide (Al2O3), and aluminum nitride (AlN).
  • SiO2 silicon dioxide
  • Si3N4 silicon nitride
  • Al2O3 aluminum oxide
  • AlN aluminum nitride
  • the depth of the cavity 230 in the film bulk acoustic wave resonator is related to the resonant frequency. Therefore, the depth of the cavity 230, that is, the thickness of the support layer 206, can be set according to the resonant frequency required by the film bulk acoustic wave resonator.
  • the depth of the cavity 230 may be 0.5 ⁇ m-4 ⁇ m, for example, 1 ⁇ m or 2 ⁇ m or 3 ⁇ m.
  • the support layer 206 is etched by an etching process to form a cavity 230, and the cavity 230 penetrates the support layer 206. In this embodiment, it is also necessary to etch away the support layer material in the second trench 220 to expose the piezoelectric layer 203 at the bottom of the second trench 220.
  • the etching process can be a wet etching or a dry etching process, and a dry etching process is preferably used. Dry etching includes but not limited to reactive ion etching (RIE), ion beam etching, and plasma etching. Body etching or laser cutting.
  • a first substrate 100 is provided, the first substrate 100 is bonded to the support layer 206, and the first substrate 100 covers the cavity 230.
  • the material of the first substrate 100 refers to the material of the second substrate.
  • the bonding of the first substrate 100 and the supporting layer 206 can be achieved by thermocompression bonding.
  • the The support layer 206 is provided with a bonding layer on the side where the thermal compression bonding is performed, and the bonding layer may be a silicon dioxide layer.
  • other bonding methods may also be used for bonding, for example, the first substrate 100 and the supporting layer 206 are bonded into one body by dry film bonding.
  • a dry film layer is provided on the side of the first substrate 100 where the dry film is bonded, and the first substrate 100 is bonded to the support layer 206 through the dry film layer.
  • the second substrate is removed, and the first electrode layer 202 is exposed.
  • the first substrate 100 may be removed through a thinning process, a heat release process, and a lift-off process.
  • the material of the release layer 201 includes a dielectric material.
  • the release layer 201 and the first substrate 100 can be removed by a thinning process, such as mechanical grinding; the release layer 201 is a photocurable glue, which can be removed by chemical reagents.
  • the photocurable adhesive is removed to remove the first substrate 100; the release layer is a hot melt adhesive, and the hot melt adhesive may lose its viscosity through a heat release process to remove the first substrate 100.
  • the release layer 201 is a laser release material, and the release layer 201 can be ablated by laser to peel off the first substrate 100.
  • the first electrode layer 202 is etched through the above step of etching the electrode layer to form at least two adjacent side surfaces to form a partial boundary of the effective resonance region.
  • the first trench 240 is etched in the first electrode layer 202, and the inner sidewalls of the first trench 240 constitute at least two side surfaces of the first electrode layer 202.
  • the first trench 240 may form a plurality of connected side surfaces to form a semi-circular shape to form part of the boundary of the effective resonance region.
  • the side surfaces formed in the first electrode layer and the second electrode layer together constitute the effective resonance region. All borders.
  • the shape of the effective resonance area is an irregular polygon, which can be quadrilateral, five-deformation, hexagon, etc.
  • the first trench 240 may extend into the piezoelectric layer 203, may penetrate the entire piezoelectric layer 203, or the bottom surface of the first trench 240 may extend to a set thickness of the piezoelectric layer 203.
  • the etching process will not be repeated.
  • the transverse parasitic waves generated in the piezoelectric layer 203 due to the mismatch between the acoustic impedance of the air and the acoustic impedance of the piezoelectric layer, propagate to the boundary of the piezoelectric layer, the sound waves are reflected back into the piezoelectric layer 203, The loss of transverse sound waves is reduced, and the quality factor of the resonator is improved.
  • the first groove 240 penetrates the entire thickness of the piezoelectric layer 203, the effect of preventing lateral acoustic wave leakage is better; when the second groove penetrates a part of the thickness of the piezoelectric layer 203, the structural strength of the resonator is better.
  • the method further includes: forming a through hole 250 penetrating the piezoelectric laminate structure above the cavity 230 and outside the effective resonance region.
  • the through hole 250 may be formed by a dry etching process or a punching process. Refer to the related description in Embodiment 1 for the number, position, and function of the through holes 250.
  • both the first electrode layer and the second electrode layer are etched using the electrode etching step described in embodiment 1.
  • only the first electrode layer or only the second electrode layer may be etched.
  • the two electrode layers (using the electrode etching step described in Embodiment 1) form the boundary of a part of the effective resonance region.
  • a part of the boundary of the effective resonance region is formed by the boundary of the piezoelectric layer, and the method further includes:
  • the piezoelectric layer is patterned to form a partial boundary of the effective resonance region.
  • the present invention also provides a thin-film bulk acoustic resonator, including an electrode layer, the electrode layer includes two adjacent side surfaces, the two adjacent side surfaces are used as two side surfaces of the effective resonance region boundary, and the adjacent two The side surfaces enclose an included angle, and the radius of the arc of the included angle is less than 1 micron.
  • the present invention also provides a filter including a plurality of the above resonators.
  • the present invention also provides an electronic device including the above filter, such as a mobile phone.

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  • Acoustics & Sound (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)

Abstract

一种薄膜体声波谐振器及其制造方法及滤波器、电子设备，其中所述制造方法包括：形成电极层（02），刻蚀所述电极层（02），所述刻蚀电极层（02）的步骤包括：在所述电极层（02）上形成光阻挡层（03），所述光阻挡层（03）能够阻止光线的通过，并能作为图形化所述电极层（02）的掩膜层；在所述光阻挡层（03）上形成光敏材料层（04）；以所述光敏材料层（04）作为掩膜，刻蚀所述光阻挡层（03），使所述光阻挡层（03）形成的图案与预形成在所述电极层（02）上的图案相同；以所述光阻挡层（03）作为掩膜，刻蚀所述电极层（02），在所述电极层（02）中形成作为有效谐振区边界的至少两个侧面，相邻两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。

Description

一种薄膜体声波谐振器及其制造方法及滤波器、电子设备 技术领域
本发明涉及半导体器件制造领域，尤其涉及一种薄膜体声波谐振器及其制造方法及滤波器、电子设备。
 背景技术
自模拟射频通讯技术在上世纪90代初被开发以来，射频前端模块已经逐渐成为通讯设备的核心组件。在所有射频前端模块中，滤波器已成为增长势头最猛、发展前景最大的部件。随着无线通讯技术的高速发展，5G通讯协议日渐成熟，市场对射频滤波器的各方面性能也提出了更为严格的标准。滤波器的性能由组成滤波器的谐振器单元决定。在现有的滤波器中，薄膜体声波谐振器(FBAR)因其体积小、插入损耗低、带外抑制大、品质因数高、工作频率高、功率容量大以及抗静电冲击能力良好等特点，成为最适合5G应用的滤波器之一。
通常，薄膜体声波谐振器包括两个薄膜电极，并且两个薄膜电极之间设有压电薄膜层，其工作原理为利用压电薄膜层在交变电场下产生振动，该振动激励出沿压电薄膜层厚度方向传播的体声波，此声波传至上下电极与空气交界面被反射回来，进而在薄膜内部来回反射，形成震荡。当声波在压电薄膜层中传播正好是半波长的奇数倍时，形成驻波震荡。
目前制作的薄膜体声波谐振器的有效谐振区一般为多边形，当多边形的两个邻边由电极的侧面构成时，由于工艺原因电极的两个侧面之间通常形成圆角，即多边形的夹角处为圆角，对于谐振器性能造成较大影响。此外，对电极进行刻蚀时，由于电极金属与光阻直接接触，去胶过程中，具有较强腐蚀性的去胶液或多或少会对电极造成损伤，而且不同区域内被刻蚀的量不稳定，最终谐振器的稳定性较差。
 技术问题
本发明的目的在于提供一种薄膜体声波谐振器的制造方法，解决构成有效谐振区边界的电极相邻的两个侧面之间形成圆角的问题。
 技术解决方案
为了实现上述目的，本发明提供一种薄膜体声波谐振器的制造方法，其特征在于，包括形成电极层,刻蚀所述电极层，所述刻蚀电极层的步骤包括：
在所述电极层上形成光阻挡层, 所述光阻挡层能够阻止光线的通过，并能作为图形化所述电极层的掩膜层；
在所述光阻挡层上形成光敏材料层；
以所述光敏材料层作为掩膜，刻蚀所述光阻挡层，使所述光阻挡层形成的图案与预形成在所述电极层上的图案相同；
以所述光阻挡层作为掩膜，刻蚀所述电极层，在所述电极层中形成作为有效谐振区边界的至少两个侧面，相邻两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。
本发明还提供了一种薄膜体声波谐振器，其特征在于，包括电极层，所述电极层包括相邻的两侧面，所述相邻的两侧面作为有效谐振区边界的两个侧面，所述相邻的两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。
本发明还提供了一种滤波器，其特征在于，包括多个上述的谐振器。
本发明还提供了一种电子设备，其特征在于，包括上述的滤波器。
 有益效果
本发明的有益效果在于，在刻蚀电极之前，先在电极表面形成光阻挡层，在光阻挡层上形成光敏材料层，光阻挡层对电极中的光有阻挡作用，减少电极中的光进入光敏材料层后产生衍射，影响光敏材料的形貌，进而影响电极的形貌。可以使构成有效谐振器边界的电极的两个相邻侧面之间的夹角为尖角，尖角的圆弧半径小于1微米，提高了谐振器的性能。
进一步地，光刻工艺中的去胶液去除光敏材料层时不与电极接触，不会损伤电极，提高了谐振器的稳定性。
进一步地，第一电极层、压电层、第二电极层依次沉积在第一衬底上，压电层下方的第一电极层未经过刻蚀，在沉积压电层时，第一电极的上表面是平整的，从而保持了压电层很好的晶向。
进一步地，第一沟槽和/或第二沟槽延伸至压电层内部或贯穿压电层，使压电层横向声波的泄露得到改善，提高了谐振器的品质因数。
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 附图说明
通过结合附图对本发明示例性实施例进行更详细的描述，本发明的上述以及其它目的、特征和优势将变得更加明显，在本发明示例性实施例中，相同的参考标号通常代表相同部件。
图1至图7为本发明实施例1的一种薄膜体声波谐振器的制造方法中刻蚀电极层的步骤对应的结构示意图。
图8至图18为本发明实施例2的一种薄膜体声波谐振器的制造方法中相应步骤中对应的结构示意图。
附图标记说明：
01-基底；02-电极层；03-光阻挡层；04-光敏材料层；05-凹槽；051-第一内侧壁；052-第二内侧壁；06-凹槽；061-第一内侧壁；062-第二内侧壁；100-第一衬底；200-第二衬底；201-释放层；202-第一电极；203-压电层；204第二电极；205-刻蚀停止层；206-支撑层； 220-第二沟槽；240-第一沟槽；通孔-250；230-空腔。
 本发明的实施方式
下面将参照附图更详细地描述本发明。虽然附图中显示了本发明的可选实施例，然而应该理解，可以以各种形式实现本发明而不应被这里阐述的实施例所限制。相反，提供这些实施例是为了使本发明更加透彻和完整，并且能够将本发明的范围完整地传达给本领域的技术人员。
以下结合附图和具体实施例对本发明的薄膜体声波谐振器、薄膜体声波谐振器的制作方法作进一步详细说明。根据下面的说明和附图，本发明的优点和特征将更清楚，然而，需说明的是，本发明技术方案的构思可按照多种不同的形式实施，并不局限于在此阐述的特定实施例。附图均采用非常简化的形式且均使用非精准的比例，仅用以方便、明晰地辅助说明本发明实施例的目的。
在说明书和权利要求书中的术语“第一”“第二”等用于在类似要素之间进行区分，且未必是用于描述特定次序或时间顺序。要理解，在适当情况下，如此使用的这些术语可替换，例如可使得本文的本发明实施例能够以不同于本文的或所示的其他顺序来操作。类似的，如果本文的方法包括一系列步骤，且本文所呈现的这些步骤的顺序并非必须是可执行这些步骤的唯一顺序，且一些的步骤可被省略和/或一些本文未描述的其他步骤可被添加到该方法。若某附图中的构件与其他附图中的构件相同，虽然在所有附图中都可轻易辨认出这些构件，但为了使附图的说明更为清楚，本说明书不会将所有相同构件的标号标于每一图中。
实施例1
本发明实施例1提供了一种薄膜体声波谐振器的制造方法，其特征在于，包括形成电极层,刻蚀所述电极层，所述刻蚀电极层的步骤包括：
S01：在所述电极层上形成光阻挡层,所述光阻挡层能够阻止光线的通过，并能作为图形化所述电极层的掩膜层
S02：在所述光阻挡层上形成光敏材料层；
S03：以所述光敏材料层作为掩膜，刻蚀所述光阻挡层，使所述光阻挡层形成的图案与预形成在所述电极层上的图案相同；
S04：以所述光阻挡层作为掩膜，刻蚀所述电极层，使所述电极层的侧面够成有效谐振区的部分边界，且所述侧面在所述光阻挡层方向上的投影为折线。
图1至图7为本发明实施例1的一种薄膜体声波谐振器的制造方法中刻蚀电极层的步骤对应的结构示意图。下面请参考图1至图7详细说明本实施例的刻蚀电极层的方法。
参考图1，在基底01上形成电极层02。
本实施例中，基底01可以是单层结构也可以是复合结构，当为单层结构时可以为半导体材料，如硅(Si)、锗(Ge)、锗硅(SiGe)、碳硅(SiC)、碳锗硅(SiGeC)、砷化铟(InAs)、砷化镓(GaAs)、磷化铟(InP)或者其它III/V化合物半导体。当为复合结构时，基底01中可以为形成有空腔，空腔中填充有牺牲层材料，牺牲层材料的顶面和基底的顶面齐平，电极层覆盖牺牲层材料和基底。
电极层02的材料可以为具有导电性能的金属材料，例如，由钼（Mo）、铝（Al）、铜（Cu）、钨（W）、钽（Ta）、铂（Pt）、钌（Ru）、铑（Rh）、铱（Ir）、铬（Cr）、钛（Ti）、金(Au)、锇(Os)、铼(Re)、钯(Pd)等金属中一种制成或由上述金属形成的叠层制成，半导体材料例如是Si、Ge、SiGe、SiC、SiGeC等。
参考图2，执行步骤S01：在所述电极层02上形成光阻挡层03，所述光阻挡层03能够阻止光线的通过，并能作为图形化所述电极层02的掩膜层。
本实施例中，通过物理气相沉积或化学气相沉积工艺在所述电极层02上沉积形成厚度为1000埃至1微米的光阻挡层03。在现有技术中，需要刻蚀电极层时，在电极层上形成光刻胶，先对光刻胶进行曝光、显影，在光刻胶中形成图案，再以光刻胶作为掩膜刻蚀电极层。然而，在对光刻胶进行曝光时，光线通过光刻胶照射到电极层02上，电极层02的材料，多为金属具有反光性，将照射在电极层上的光，反射进入光刻胶层，反射的光对光刻胶不希望进行曝光的区域进行了曝光，使光刻胶中形成的图形形状与设计的形状有差别，当以光刻胶作为掩膜刻蚀电极层时，电极层中形成的图案也因此发生了变化，尤其当电极层中形成两个交接面时，两个交接面之间形成的夹角为圆弧状（希望形成没有圆弧状的尖角）。本实施例中，在形成光刻胶之前在电极层02上形成光阻挡层03，所述光阻挡层03能够阻止光线的通过，并能作为图形化所述电极层的掩膜层。具体地，光阻挡层03一方面可以防止电极层02的光进入后期工艺中形成在光阻挡层上方的光敏材料层中，另一方面，防止通过光敏材料层的光反射回所述光敏材料层。因此，在光敏材料层中形成的图案可以和设计的一致，在后期工艺中，光阻挡层03形成的图案和光敏材料层中的图案一致，因此在电极层02中形成的图案可以和光阻挡层03中形成的图案一致。可以使构成有效谐振器边界的电极的两个相邻侧面之间的夹角圆弧半径小于1微米，提高谐振器的性能。现有工艺中，两个交接面之间的圆弧半径一半大于2微米。所述光阻挡层03的材料包括：无定型碳、二氧化硅、氮化硅、氮氧化硅。
参考图3，执行步骤S02：在所述光阻挡层03上形成光敏材料层04。
本实施例中，光敏材料层04为光刻胶，可以通过旋涂工艺在光阻挡层03上形成预定厚度的光刻胶。在其他实施例中，光敏材料层还可以是其他对光敏感的材料，如有机固化膜。
参考图4和图5，执行步骤S03：以所述光敏材料层04作为掩膜，刻蚀所述光阻挡层03，使所述光阻挡层03形成的图案与预形成在所述电极层02上的图案相同。
本实施例中，光阻挡层03的材料为无定形碳，刻蚀所述光阻挡层03包括：对所述光敏材料层进行曝光、显影后，在压力为10~30毫托的环境下，刻蚀气体采用氧气和四氟化碳刻蚀所述光阻挡层。在另一个实施例中，光阻挡层03的材料为二氧化硅或氮化硅，刻蚀所述光阻挡层包括：对所述光敏材料层进行曝光、显影后，在压力为50~100毫托的环境下，刻蚀气体采用四氟化碳或八氟环丁烷或八氟环戊烯刻蚀所述光阻挡层03。在光阻挡层03中刻蚀形成凹槽05，凹槽05包含相接的第一内侧壁051和第二内侧壁052，根据步骤S01中所描述，第一内侧壁051和第二内侧壁052之间的夹角的圆弧半径小于1微米。
参考图6和图7，执行步骤S04：以所述光阻挡层03作为掩膜，刻蚀所述电极层02，在所述电极层02中形成作为有效谐振区边界的至少两个侧面，相邻两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。
本实施例中，电极层02的材料为钼，刻蚀所述电极层包括：在压力为10~50mtorr的环境下，采用氟化硫刻蚀气体刻蚀所述电极层02。刻蚀所述电极层02时，以光阻挡层03作为掩膜，沿着凹槽05的第一内侧壁051和第二内侧壁052向下刻蚀，形成凹槽06，在竖直方向上，凹槽06的第一内侧壁061和凹槽05的第一内侧壁051相重合，凹槽06的第二内侧壁062和凹槽05的第二内侧壁052相重合，第一内侧壁061和第二内侧壁062之间的夹角与第一内侧壁051和第二内侧壁052之间的夹角形貌一致。第一内侧壁061和第二内侧壁062构成电极层的两个侧面，构成有效谐振区的部分边界。在其他实施例中，凹槽的侧壁可以为多个，比如3个侧壁形成半环形，构成有效谐振区的部分边界。
本实施例中，刻蚀所述光阻挡层03后，刻蚀所述电极层02前还包括：去除所述光敏材料层。本实施例中，光敏材料层的材质为光刻胶，去除光刻胶所采用的化学溶液为弱碱性溶液。在现有技术中，光刻胶形成在电极层之上，去除光刻胶时，用于去除光刻胶的溶液与电极层直接接触，对电极层造成损伤，本实施例中，去除所述光敏材料层时，化学溶液不与电极层接触，不会损伤电极，提高了谐振器的稳定性。
本实施例中，刻蚀所述电极层02后，还包括:去除所述光阻挡层02。当所述光阻挡层的材质为无定型碳时，用灰化方法去除所述光阻挡层02，当所述光阻挡层的材料为二氧化硅时，用氢氟酸溶剂去除所述光阻挡层02。
实施例2
体声波谐振器包括两个电极层，本实施例中，分别对第一电极层和第二电极层采用上述的电极层刻蚀工艺，图8至图18为本发明实施例2的一种薄膜体声波谐振器的制造方法中相应步骤中对应的结构示意图。下面请参考图8至图18详细说明本实施例的薄膜体声波谐振器的制作方法。
参考图8至图10，提供第二衬底200，在所述第二衬底200上形成压电叠层结构，所述压电叠层结构包括依次沉积在所述第二衬底200上的第一电极层202、压电层203及第二电极层204。通过上述刻蚀电极层的步骤对所述第二电极层204进行刻蚀，所述至少两个侧面构成有效谐振区的部分边界。有效谐振区中的第一电极层、压电层及第二电极层相互叠置。
第二衬底200的材料参照前文基底的材料，此处不在赘述。
参考图9，本实施例中，在形成压电叠层结构之前还包括在所述第二衬底200上形成释放层201，所述释放层201可以避免后续形成的薄膜体声波谐振器的压电叠层结构对第二衬底200的影响，同时，在后续第二衬底200的去除工艺中，可以通过腐蚀所述释放层201的方式，使所述第二衬底200与后续形成的压电叠层结构分离，有助于快速去除所述第二衬底200，提高工艺制作效率。所述释放层201的材质包括但不限于二氧化硅(SiO2)、氮化硅(Si3N4)、氧化铝（Al2O3）和氮化铝（AlN）中的至少一种。所述释放层201可通过化学气相沉积、磁控溅射或蒸镀等方式形成。本实施例中所述第二衬底200为硅晶圆，所述释放层201的材质为二氧化硅(SiO2)。
参考图10，在所述第二衬底200上依次沉积形成第一电极层202、压电层203及第二电极层204。第一电极层202可用作接收或提供诸如射频(RF)信号等的电信号的输入电极或输出电极。例如，当第二电极层204用作输入电极时，第一电极层202可用作输出电极，并且当第二电极层204用作输出电极时，第一电极层202可用作输入电极，压电层203将通过第一电极层202或第二电极层204上输入的电信号转换为体声波。例如，压电层203通过物理振动将电信号转换为体声波。
第一电极层202、第二电极层204的材料参照实施例1中电极层的材料，可以通过磁控溅射、蒸镀等物理气相沉积或者化学气相沉积方法形成第一电极层202和第二电极层204。
压电层203的材料可以使用氮化铝(AlN)、氧化锌(ZnO)、锆钛酸铅(PZT)、铌酸锂(LiNbO3)、石英(Quartz)、铌酸钾(KNbO3)或钽酸锂(LiTaO3)等具有纤锌矿型结晶结构的压电材料及它们的组合。当压电层104包括氮化铝(AlN)时，压电层203还可包括稀土金属，例如钪(Sc)、铒(Er)、钇(Y)和镧(La)中的至少一种。此外，当压电层203包括氮化铝(AlN)时，压电层203还可包括过渡金属，例如锆(Zr)、钛(Ti)、锰(Mn)和铪(Hf)中的至少一种。，可以使用化学气相沉积、物理气相沉积或原子层沉积的方法沉积形成压电层203。本实施例中，第一电极层202、压电层203、第二电极层204依次沉积在第二衬底200上，压电层203下方的第一电极层202未经过刻蚀，在沉积压电层203时，第一电极层202的上表面是平整的，从而保持了压电层203很好的晶向。
参考图11，在另一个实施例中，形成完压电叠层结构之后还包括，在第二电极层204上形成刻蚀停止层205，可以使用化学气相沉积、物理气相沉积或原子层沉积的方法沉积形成刻蚀停止层205。所述刻蚀停止层205的材质包括但不限于氮化硅（Si3N4）和氮氧化硅（SiON）。所述刻蚀停止层205与后期工艺中形成的支撑层相比，具有较低的刻蚀速率，在制造工艺时，可以在刻蚀所述支撑层形成空腔230时防止过刻蚀，保护位于其下的第二电极层204的表面不受到损伤。
参考图12，本实施例中，在第二电极层204中，按照前文所述的刻蚀电极层的工艺步骤刻蚀出第二沟槽220，第二沟槽220的内侧壁构成所述第二电极层204的至少两个侧面。所述至少两个侧面构成有效谐振区的部分边界。
第二沟槽220也可以形成多个相接的侧面，如3个侧面，构成半环形，构成有效谐振区的部分边界。
在一个实施例中，第二沟槽220可以延伸至压电层203中，可以贯穿整个压电层203，或者第二沟槽220的底面延伸至压电层203的设定厚度。这种设置方式，压电层203中产生的横向寄生波，由于空气的声阻抗和压电层的声阻抗失配，传播至压电层边界处时，声波被反射回压电层203内，减少了横向声波的损失，提高了谐振器的品质因数。当第二沟槽220贯穿压电层203全部厚度时，防止横向声波泄露的效果更好；当第二沟槽220贯穿压电层203的一部分厚度时，谐振器的结构强度更好。
参考图13至图17，本实施例中，还包括刻蚀第一电极层202。
刻蚀完第二电极层204后，在所述第二电极层204上形成支撑层206；
在所述支撑层206中形成所述空腔230，所述空腔230贯穿所述支撑层206；
提供第一衬底100，将所述第一衬底100键合在所述支撑层206上，所述第一衬底100覆盖所述空腔230；
去除所述第二衬底200，暴露出所述第一电极层202；
通过所述刻蚀电极层的步骤对所述第一电极层202进行刻蚀，所述至少两个侧面构成有效谐振区的部分边界。
首先，可以通过化学沉积的方法形成支撑层206，支撑层206的材质可以为二氧化硅（SiO2）、氮化硅(Si3N4)、氧化铝（Al2O3）和氮化铝（AlN）的一种或几种组合。薄膜体声波谐振器中空腔230的深度与谐振频率有关，因此，可以根据薄膜体声波谐振器所需要的谐振频率来设定空腔230的深度，即所述支撑层206的厚度。示例性的，所述空腔230深度可以为0.5μm~4μm，例如1μm或2μm或3μm。通过刻蚀工艺刻蚀所述支撑层206形成空腔230，空腔230贯穿所述支撑层206。本实施例中，还需要刻蚀掉第二沟槽220中的支撑层材料，暴露出第二沟槽220底部的压电层203。该刻蚀工艺可以是湿法刻蚀或者干法刻蚀工艺，其中较佳地使用干法刻蚀工艺，干法刻蚀包括但不限于反应离子刻蚀(RIE)、离子束刻蚀、等离子体刻蚀或者激光切割。
参考图15，提供第一衬底100，将所述第一衬底100键合在所述支撑层206上，所述第一衬底100覆盖所述空腔230。
第一衬底100的材料参照第二衬底的材料。可以通过热压键合的方式实现所述第一衬底100与所述支撑层206的键合，为增加所述支撑层206与所述第一衬底100的键合能力，可以在所述支撑层206进行热压键合的一面设置有键合层，所述键合层可以为二氧化硅层。在本发明其他实施例中也可以通过其他键合方式进行键合，如通过干膜粘合的方式使第一衬底100与所述支撑层206键合成为一体。在所述第一衬底100进行干膜粘合的一面设置有干膜层，通过干膜层将所述第一衬底100与所述支撑层206键合。完成键合工艺后，将键合后的上述薄膜体声波谐振器进行翻转。
参考图16，去除所述第二衬底，暴露出所述第一电极层202。可以通过减薄工艺、热释放工艺、剥离工艺去除所述第一衬底100。例如所述释放层201的材料包括电介质材料，可以通过减薄工艺去除所述释放层201和所述第一衬底100，如机械研磨；所述释放层201为光固化胶，可以通过化学试剂去除所述光固化胶，以去除所述第一衬底100；所述释放层为热熔胶，可以通过热释放工艺使得所述热熔胶失去粘性，以去除所述第一衬底100。所述释放层201为激光脱模材料，可以通过激光烧蚀所述释放层201，以将所述第一衬底100剥离下来。
参照图17，通过上述的刻蚀电极层的步骤对所述第一电极层202进行刻蚀，形成至少两个相接的侧面，构成有效谐振区的部分边界。本实施例中，在第一电极层202中刻蚀出第一沟槽240，由第一沟槽240的内侧壁构成所述第一电极层202的至少两个侧面。第一沟槽240可以形成多个相接的侧面，构成半环形，形成有效谐振区的部分边界本实施例中，形成在第一电极层和第二电极层中的侧面共同构成了有效谐振区的全部边界。有效谐振区的形状为不规则多边形，可以是四边形、五变形、六边形等。
在一个实施例中，第一沟槽240可以延伸至压电层203中，可以贯穿整个压电层203，或者第一沟槽240的底面延伸至压电层203的设定厚度。刻蚀工艺不再赘述。这种设置方式，压电层203中产生的横向寄生波，由于空气的声阻抗和压电层的声阻抗失配，传播至压电层边界处时，声波被反射回压电层203内，减少了横向声波的损失，提高了谐振器的品质因数。当第一沟槽240贯穿压电层203全部厚度时，防止横向声波泄露的效果更好；当第二沟槽贯穿压电层203的一部分厚度时，谐振器的结构强度更好。
参考图18，本实施例中，去除所述第二衬底后还包括：在所述空腔230上方、所述有效谐振区的外部形成贯穿所述压电叠层结构的通孔250。
可以通过干法刻蚀工艺或打孔工艺形成通孔250。通孔250的数量、位置、作用等参照实施例1中的相关描述。
本实施例中，刻蚀第一电极层和第二电极层均采用实施例1所描述的刻蚀电极的步骤，在其他实施例中，也可以只刻蚀第一电极层或只刻蚀第二电极层（采用实施例1所描述的刻蚀电极的步骤），形成部分有效谐振区的边界。
在另一个实施例中，有效谐振区的一部分边界由所述压电层的边界构成，所述方法还包括：
刻蚀所述第一电极层或第二电极层之后，对所述压电层进行图形化，形成有效谐振区的部分边界。
本发明还提供一种薄膜体声波谐振器，包括电极层，所述电极层包括相邻的两侧面，所述相邻的两侧面作为有效谐振区边界的两个侧面，所述相邻的两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。
本发明还提供一种包括多个以上谐振器的滤波器。
本发明还提供一种包括以上滤波器的电子设备，比如手机等。
以上已经描述了本发明的各实施例，上述说明是示例性的，并非穷尽性的，并且也不限于所披露的各实施例。在不偏离所说明的各实施例的范围和精神的情况下，对于本技术领域的普通技术人员来说许多修改和变更都是显而易见的。工业实用性

Claims (20)

  1. 一种薄膜体声波谐振器的制造方法，其特征在于，包括形成电极层，刻蚀所述电极层，所述刻蚀电极层的步骤包括：
    在所述电极层上形成光阻挡层, 所述光阻挡层能够阻止光线的通过，并能作为图形化所述电极层的掩膜层；
    在所述光阻挡层上形成光敏材料层；
    以所述光敏材料层作为掩膜，刻蚀所述光阻挡层，使所述光阻挡层形成的图案与预形成在所述电极层上的图案相同；
    以所述光阻挡层作为掩膜，刻蚀所述电极层，在所述电极层中形成作为有效谐振区边界的至少两个侧面，相邻两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。
  2. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，刻蚀所述电极层后，还包括:去除所述光阻挡层。
  3. 根据权利要求2所述的薄膜体声波谐振器的制造方法，其特征在于，所述光阻挡层的材质为无定型碳，用灰化方法去除所述光阻挡层或，所述光阻挡层的材料为二氧化硅，用氢氟酸溶剂去除所述光阻挡层。
  4. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，所述光阻挡层的材料包括：无定型碳、二氧化硅、氮化硅、氮氧化硅。
  5. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，刻蚀所述光阻挡层后，刻蚀所述电极层前还包括：去除所述光敏材料层。
  6. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，在所述电极层上形成光阻挡层包括：通过沉积工艺在所述电极层上形成厚度为1000埃至1微米的光阻挡层。
  7. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，
    当所述光阻挡层的材料为无定形碳时，刻蚀所述光阻挡层包括：对所述光敏材料层进行曝光、显影后，在压力为10~30毫托的环境下，刻蚀气体采用氧气和四氟化碳刻蚀所述光阻挡层；
    当所述光阻挡层的材料为二氧化硅或氮化硅时，刻蚀所述光阻挡层包括：对所述光敏材料层进行曝光、显影后，在压力为50~100毫托的环境下，刻蚀气体采用四氟化碳或八氟环丁烷或八氟环戊烯刻蚀所述光阻挡层。
  8. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，所述电极层的材料为钼，刻蚀所述电极层包括：在压力为10~50mtorr的环境下，采用氟化硫刻蚀气体刻蚀所述电极层。
  9. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，所述谐振器包括第一电极层和第二电极层，所述电极层为所述谐振器的第二电极层，所述制造方法还包括：
    提供第二衬底；
    在所述第二衬底上形成压电叠层结构，所述压电叠层结构包括依次沉积在所述第二衬底上的第一电极层、压电层及第二电极层；
    通过所述刻蚀电极层的步骤对所述第二电极层进行刻蚀，所述至少两个侧面构成有效谐振区的部分边界。
  10. 根据权利要求9所述的薄膜体声波谐振器的制造方法，其特征在于，所述电极层还包括所述谐振器的第一电极层，所述制造方法还包括：
    刻蚀所述第二电极层后，在所述第二电极层上形成支撑层，所述支撑层的材质包括：二氧化硅、氮化硅、氧化铝和氮化铝中的一种或多种组合；
    在所述支撑层中形成所述空腔，所述空腔贯穿所述支撑层；
    提供第一衬底，将所述第一衬底键合在所述支撑层上，所述第一衬底覆盖所述空腔；
    去除所述第二衬底，暴露出所述第一电极层；
    通过所述刻蚀电极层的步骤对所述第一电极层进行刻蚀，所述至少两个侧面构成有效谐振区的部分边界。
  11. 根据权利要求1所述的薄膜体声波谐振器的制造方法，其特征在于，刻蚀所述电极层形成的所述侧面为电极层中形成的沟槽的内侧壁。
  12. 根据权利要求11所述的薄膜体声波谐振器的制造方法，其特征在于，所述沟槽贯穿所述电极层，底面停止于所述压电层表面或者压电层中。
  13. 根据权利要求9所述的薄膜体声波谐振器的制作方法，其特征在于，在形成所述第一电极层之前，还包括：
    在所述第一衬底上形成释放层。
  14. 根据权利要求10所述的薄膜体声波谐振器的制作方法，其特征在于，在形成所述支撑层之前，形成所述第二电极层之后，还包括：在所述第二电极层上形成刻蚀停止层，所述刻蚀停止层的材质包括：二氧化硅、氮化硅、氮氧化硅中的一种或多种组合。
  15. 根据权利要求10所述的薄膜体声波谐振器的制作方法，其特征在于，通过热压键合或干膜粘合的方式实现所述第二衬底与所述支撑层的键合。
  16. 根据权利要求10所述的薄膜体声波谐振器的制作方法，其特征在于，去除所述第一衬底的方法包括：
    减薄工艺、热释放工艺、剥离工艺其中之一。
  17. 根据权利要求13所述的薄膜体声波谐振器的制作方法，其特征在于，所述释放层的材料包括电介质材料，并通过减薄工艺去除所述释放层和所述第二衬底，或
    所述释放层为光固化胶，并通过化学试剂去除所述光固化胶，以去除所述第二衬底，或
    所述释放层为热熔胶，并通过热释放工艺使得所述热熔胶失去粘性，以去除所述第二衬底，或
    所述释放层为激光脱模材料，并通过激光烧蚀所述释放层，以将所述第二衬底剥离下来。
  18. 一种薄膜体声波谐振器，其特征在于，包括电极层，所述电极层包括相邻的两侧面，所述相邻的两侧面作为有效谐振区边界的两个侧面，所述相邻的两侧面围成有一夹角，所述夹角的圆弧半径小于1微米。
  19. 一种滤波器，其特征在于，包括多个权利要求19所述的谐振器。
  20. 一种电子设备，其特征在于，包括权利要求19所述的滤波器。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115001426A (zh) * 2022-04-26 2022-09-02 浙江大学杭州国际科创中心 一种基于多次键合工艺的薄膜体声波谐振器的制备方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112039476B (zh) * 2020-03-17 2024-03-12 中芯集成电路（宁波）有限公司 一种薄膜体声波谐振器及其制造方法及滤波器、电子设备
CN113258899A (zh) * 2021-05-18 2021-08-13 苏州汉天下电子有限公司 一种薄膜体声波谐振器及其制造方法
CN117895916A (zh) * 2024-03-14 2024-04-16 深圳新声半导体有限公司 一种集成式baw滤波器和制造集成式baw滤波器的方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103077925A (zh) * 2011-10-25 2013-05-01 中芯国际集成电路制造(上海)有限公司 存储器的制造方法
WO2018100840A1 (ja) * 2016-11-29 2018-06-07 株式会社村田製作所 弾性波装置及びその製造方法、高周波フロントエンド回路、並びに通信装置
CN109150135A (zh) * 2018-11-13 2019-01-04 杭州左蓝微电子技术有限公司 基于键合的薄膜体声波谐振器及其加工方法
CN110868187A (zh) * 2019-11-25 2020-03-06 武汉大学 一种基于弧形电极的超高频谐振器结构
CN112039476A (zh) * 2020-03-17 2020-12-04 中芯集成电路（宁波）有限公司 一种薄膜体声波谐振器及其制造方法及滤波器、电子设备

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005348357A (ja) * 2004-06-07 2005-12-15 Sony Corp 薄膜バルク音響共振器
JP5184179B2 (ja) * 2008-03-28 2013-04-17 京セラ株式会社 薄膜共振子、フィルタおよびデュプレクサ
CN110571219B (zh) * 2018-06-05 2021-09-03 中芯国际集成电路制造(上海)有限公司 半导体器件及其制造方法和掩膜板

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103077925A (zh) * 2011-10-25 2013-05-01 中芯国际集成电路制造(上海)有限公司 存储器的制造方法
WO2018100840A1 (ja) * 2016-11-29 2018-06-07 株式会社村田製作所 弾性波装置及びその製造方法、高周波フロントエンド回路、並びに通信装置
CN109150135A (zh) * 2018-11-13 2019-01-04 杭州左蓝微电子技术有限公司 基于键合的薄膜体声波谐振器及其加工方法
CN110868187A (zh) * 2019-11-25 2020-03-06 武汉大学 一种基于弧形电极的超高频谐振器结构
CN112039476A (zh) * 2020-03-17 2020-12-04 中芯集成电路（宁波）有限公司 一种薄膜体声波谐振器及其制造方法及滤波器、电子设备

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115001426A (zh) * 2022-04-26 2022-09-02 浙江大学杭州国际科创中心 一种基于多次键合工艺的薄膜体声波谐振器的制备方法
CN115001426B (zh) * 2022-04-26 2024-05-17 浙江大学杭州国际科创中心 一种基于多次键合工艺的薄膜体声波谐振器的制备方法

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