WO2020132993A1 - 柔性基底薄膜体声波滤波器的连接结构 - Google Patents

柔性基底薄膜体声波滤波器的连接结构 Download PDF

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Publication number
WO2020132993A1
WO2020132993A1 PCT/CN2018/124073 CN2018124073W WO2020132993A1 WO 2020132993 A1 WO2020132993 A1 WO 2020132993A1 CN 2018124073 W CN2018124073 W CN 2018124073W WO 2020132993 A1 WO2020132993 A1 WO 2020132993A1
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Prior art keywords
acoustic wave
wave filter
bulk acoustic
flexible
top electrode
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English (en)
French (fr)
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庞慰
高传海
张孟伦
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Tianjin University
ROFS Microsystem Tianjin Co Ltd
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Tianjin University
ROFS Microsystem Tianjin Co Ltd
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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 elements; 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 elements; Electromechanical resonators
    • H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
    • H03H9/56—Monolithic crystal filters

Definitions

  • the invention relates to the technical field of semiconductors, in particular to a connection structure of a flexible base film bulk acoustic wave filter.
  • Filters are one of the most commonly used electrical components in modern communication systems. Filters are divided according to function, which can be divided into low-pass, high-pass, band-pass and band-reject filters.
  • flexible electronics has also developed rapidly. So far, flexible electronics has developed rapidly in the fields of display, sensing, communication, etc., and wearable flexible electronic consumer has attracted more and more interest.
  • Flexible electronics is generally considered to be an electronic or electronic system built on a flexible substrate. The system has the characteristics of being bendable, stretchable and twisted. Compared with conventional electronic systems on hard substrates, flexible electronics need to retain a certain working capacity when flexible deformation occurs. In applications with high communication efficiency, the construction of a flexible radio frequency system can further expand the field of flexible applications.
  • the filter can be regarded as a two-port network, and Port 1 and Port 2 in Figure 1 are the signal input and output respectively.
  • two resonators include two resonance points: a series resonance point with a lower frequency and a parallel resonance point with a higher frequency. Taking a band-pass filter as an example, in a filter with a ladder structure, the parallel resonance point of the parallel resonator and the series resonance point of the series resonator are often equal to obtain a filter with better performance, as shown in FIG. 2.
  • BAW Bulk Acoustic Wave
  • a bulk acoustic wave film bulk acoustic wave resonator (Film, Acoustic, Resonator, FBAR) as an example
  • this type of resonator has a sandwich structure, from top to bottom are top electrode (Top Electrode, TE), piezoelectric layer ( Piezoelectric Layer (PZ) and bottom electrode (Bottom Electrode, BE) can produce electrical resonance under external RF voltage.
  • top electrode Top Electrode, TE
  • piezoelectric layer Piezoelectric Layer (PZ)
  • Bottom electrode Bottom electrode
  • BE Bottom Electrode
  • BAW resonators and their extended filters on hard substrates has become mature in terms of commercialization, but if the process is directly applied to flexible filters, the device flexibility is still not ideal.
  • FIG. 3a the circuit schematic diagram of two adjacent resonators without electrical links is shown in FIG. 3a
  • FIG. 3b the cross-sectional view of the prior art device structure is shown in FIG. 3b, including a top electrode 310, a piezoelectric layer 311, a bottom electrode 312, and a flexible substrate 320, wherein The top surface of the flexible substrate 320 has a cavity 330 aligned with the top electrode. Since the piezoelectric layer 311 is usually a brittle material, the flexibility of the device is not ideal.
  • FIG. 4a the circuit schematic diagram of the adjacent resonator of the top electrode isolation type series-parallel structure is shown in FIG. 4a, and the cross-sectional view of the structure of the prior art device is shown in FIG. 4b.
  • 420 wherein the top surface of the flexible substrate 420 has a cavity 430 aligned with the top electrode. Since the piezoelectric layer 411 is usually a brittle material, the flexibility of the device is not ideal.
  • the present invention provides a connection structure of a flexible base film bulk acoustic wave filter, which is beneficial to improve the flexibility of the device.
  • connection structure of the flexible base film bulk acoustic wave filter proposed by the present invention includes: a first top electrode and a second top electrode with a gap between the two; a piezoelectric layer under the first top electrode and the second top electrode; One or two bottom electrodes under the piezoelectric layer; a flexible substrate under the bottom electrode; wherein the piezoelectric layer is not provided under the gap between the two top electrodes.
  • the bottom electrode is a first bottom electrode and a second bottom electrode, respectively corresponding to the first top electrode and the second top electrode; the first bottom electrode and the second top electrode pass through The conductive film is connected, and the conductive film is located in the gap and below the gap.
  • a flexible material is filled on the conductive film.
  • the position below the gap that does not have the piezoelectric layer is filled with a flexible material.
  • the gap and the position below the gap without the piezoelectric layer are filled with a flexible material, wherein the flexible material covers the edge of the top electrode.
  • the flexible material is epoxy resin or parylene.
  • the material of the flexible substrate includes: polyethylene terephthalate plastic, polyethyleneimide, polyethylene naphthalate or polyetherimide.
  • the top surface of the flexible substrate has two cavities, and the two cavities are respectively aligned with the first top electrode and the second top electrode.
  • a Bragg reflective layer is provided between the flexible substrate and the bottom electrode.
  • the Bragg reflective layer is prepared separately and then transferred onto the flexible substrate.
  • the material of the piezoelectric layer includes aluminum nitride, zinc oxide, lead zirconate titanate piezoelectric ceramic, or polyvinylidene fluoride.
  • the device since there is no brittle piezoelectric material under the gap between the two top electrodes, the device has the advantage of good flexibility.
  • Figure 1 is a circuit diagram of the ladder topology of the filter
  • Figure 2 is a schematic diagram of the performance of the resonance unit and the filter
  • FIG. 3a is a schematic circuit diagram of two adjacent resonators without electrical links
  • FIG. 3b is a cross-sectional view of a device structure of two adjacent resonators without electrical links in the prior art
  • FIG. 4a is a schematic circuit diagram of an adjacent resonator of a top electrode isolation type series-parallel structure
  • FIG. 4b is a cross-sectional view of a device structure of a prior art top electrode isolation type resonator
  • FIG. 5 is a cross-sectional view of a device structure of two adjacent resonators without electrical links according to an embodiment of the present invention
  • FIG. 6 is a cross-sectional view of a device structure of an adjacent resonator of a top electrode isolation type series-parallel structure according to an embodiment of the present invention
  • FIG. 7a is a circuit diagram of an adjacent resonator with a top-electrode and bottom-electrode series-connected structure according to an embodiment of the invention
  • FIG. 7b is a cross-sectional view of a device structure corresponding to FIG. 7a
  • FIG. 7c is another device corresponding to FIG. 7a Structural section
  • FIG. 8 is a cross-sectional view of a device structure filled with a flexible material at a position without the piezoelectric layer under the gap between two top electrodes according to an embodiment of the present invention
  • FIG. 9 is a cross-sectional view of a device structure filled with a flexible material at a gap between two top electrodes and a position under the gap without the piezoelectric layer according to an embodiment of the present invention.
  • FIG. 10 is a cross-sectional view of a device structure of two adjacent resonators with Bragg reflective layers according to an embodiment of the present invention.
  • first and second are used for description purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features.
  • the features defined as “first” and “second” may explicitly or implicitly include one or more of the features.
  • the meaning of “plurality” is two or more, unless otherwise specifically limited.
  • the terms “installation”, “connected”, “connected”, “fixed” and other terms should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , Or integrally connected; it can be a mechanical connection or an electrical connection; it can be directly connected, or it can be indirectly connected through an intermediary, or it can be the connection between two components.
  • installation can be a fixed connection or a detachable connection , Or integrally connected; it can be a mechanical connection or an electrical connection; it can be directly connected, or it can be indirectly connected through an intermediary, or it can be the connection between two components.
  • the first feature “above” or “below” the second feature may include the first and second features in direct contact, or may include the first and second features Not direct contact but contact through another feature between them.
  • the first feature is “above”, “above” and “above” the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature.
  • the first feature is “below”, “below” and “below” the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the first feature is less horizontal than the second feature.
  • connection structure of a flexible base film bulk acoustic wave filter includes: a first top electrode and a second top electrode with a gap between them; a piezoelectric layer under the first top electrode and the second top electrode; One or two bottom electrodes below the piezoelectric layer; a flexible substrate below the bottom electrode; wherein, there is no piezoelectric layer below the gap between the two top electrodes.
  • a first top electrode and a second top electrode with a gap between them
  • a piezoelectric layer under the first top electrode and the second top electrode One or two bottom electrodes below the piezoelectric layer
  • a flexible substrate below the bottom electrode wherein, there is no piezoelectric layer below the gap between the two top electrodes.
  • the structure includes a top electrode 510, a piezoelectric layer 511, a bottom electrode 512, and a flexible substrate 520, where the top surface of the flexible substrate 520 may have a cavity 530 aligned with the top electrode.
  • the filter without the substrate is first manufactured by the MEMS process, and secondly, the cavity is etched on the flexible substrate, and then the device is transferred by the transfer method Align with the cavity and transfer fixed to the flexible substrate.
  • the transfer method Align with the cavity and transfer fixed to the flexible substrate Align with the cavity and transfer fixed to the flexible substrate.
  • FIG. 6 is a structural cross-sectional view of a TE-isolated series-parallel structure resonator according to an embodiment of the present invention (the circuit diagram corresponds to FIG. 4a).
  • the structure includes a top electrode 610, a piezoelectric layer 611, a bottom electrode 612, and a flexible substrate 620, where the top surface of the flexible substrate 620 may have a cavity 630 aligned with the top electrode.
  • the bottom electrode is a first bottom electrode and a second bottom electrode, respectively corresponding to the first top electrode and the second top electrode; the first bottom The electrode and the second top electrode are connected via a conductive film, and the conductive film is located below the gap and the gap.
  • the conductive film connected to the electrode may also be filled with a flexible material. Specifically, it can be described in conjunction with Example 3.
  • FIG. 7a is a circuit diagram of an adjacent resonator with a top electrode and a bottom electrode connected in series
  • FIG. 7b is a cross-sectional view of a device structure corresponding to FIG. 7a.
  • the structure includes: a top electrode 710, a piezoelectric layer 720, a bottom electrode 730, a conductive film 740, and a flexible substrate 750, wherein the top surface of the flexible substrate 720 may have a cavity aligned with the top electrode 770.
  • the bottom electrode of the left resonator is connected to the top electrode of the right resonator through a conductive film, and the predefined top electrode and bottom electrode of the right resonator are exchanged.
  • the formation of the conductive thin film 740 can be achieved by existing processes, for example, in combination with processes such as photolithography, using magnetron sputtering or other methods to deposit materials on the target area.
  • FIG. 7c is a cross-sectional view of another device structure corresponding to FIG. 7a.
  • the gap above the conductive film 740 is filled with a flexible material 760 to obtain higher mechanical stability.
  • the filled flexible material includes but is not limited to epoxy resin (for example, photoresist based on epoxy SU-8 resin) or parylene.
  • connection structure of the flexible base film bulk acoustic wave filter of the embodiment of the present invention the position below the gap without the piezoelectric layer is filled with a flexible material; specifically, it can be described in conjunction with Example 4.
  • the structure includes two adjacent top electrodes 810, a piezoelectric layer 811, a bottom electrode 812, and a flexible substrate 820, wherein the top surface of the flexible substrate 820 may have a cavity 830 aligned with the top electrode.
  • the gap between the two top electrodes 810 is filled with a flexible material 860.
  • the gap and the position below the gap without the piezoelectric layer are filled with a flexible material, wherein the flexible material covers the edge of the top electrode , which can effectively prevent the top electrode from lifting. Specifically, it can be described in conjunction with Example 5.
  • the structure includes two adjacent top electrodes 910, a piezoelectric layer 911, a bottom electrode 912, and a flexible substrate 920, wherein the top surface of the flexible substrate 920 may have a cavity 930 aligned with the top electrode.
  • the gap between the two top electrodes 910 is filled with a flexible material 960.
  • connection structure of the flexible base film bulk acoustic wave filter of the embodiment of the present invention there is a Bragg reflection layer between the flexible base and the bottom electrode.
  • the Bragg reflective layer and device are first manufactured by MEMS process. Secondly, the device is directly transferred and fixed to the flexible substrate by a transfer method.
  • the Bragg reflection layer is obtained by cross-stacking multiple layers of materials with different acoustic impedances (low-acoustic impedance materials-high-acoustic impedance materials-low-acoustic impedance materials-high-acoustic impedance materials are cross-stacked in this way).
  • the Bragg reflection structure generally has at least 4 layers, and the number of layers can also be more.
  • Common low acoustic impedance materials are silicon dioxide (SiO 2 ), metal aluminum (Al), etc.
  • common high acoustic impedance materials are metal molybdenum (Mo), tungsten (W), etc.
  • the low/ The high acoustic impedance material is not limited to one material, and may be a mixture of these materials. Specifically, it can be described in conjunction with Example 6.
  • the structure includes two adjacent top electrodes 1010, a piezoelectric layer 1011, a bottom electrode 1012, and a flexible substrate 1020, in which there are two layers of low acoustic impedance materials 1030 stacked crosswise between the bottom electrode 1012 and the flexible substrate 1020 and High acoustic impedance material 1031.
  • the flexible material in all embodiments of the present invention may be epoxy resin or parylene; the material of the flexible substrate includes, but is not limited to, polyethylene terephthalate (PET), polyacetimide (PI ), polyethylene naphthalate (PEN), polyetherimide (PEI), etc.
  • PET polyethylene terephthalate
  • PI polyacetimide
  • PEN polyethylene naphthalate
  • PEI polyetherimide
  • the material of the piezoelectric layer includes but is not limited to aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate piezoelectric ceramic (PZT) and polyvinylidene fluoride (PVDF), etc., or may be doped with other elements Of the above materials.
  • the above-mentioned materials are piezoelectric thin films with a thickness of less than 10 microns.
  • the aluminum nitride thin film is in a polycrystalline or single crystal form, and the growth method is thin film sputtering (sputtering) or organic metal chemical vapor deposition (MOCVD).
  • connection structure of the flexible base film bulk acoustic wave filter of the embodiment of the present invention enhances the flexibility of the device by reducing the brittle piezoelectric material between the gaps between the two top electrodes.

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  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Chemical & Material Sciences (AREA)
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Abstract

一种柔性基底薄膜体声波滤波器的连接结构，包括：第一顶电极和第二顶电极，二者之间具有间隙；所述第一顶电极和第二顶电极下方的压电层（511,611,720,811,911,1011）；所述压电层（511,611,720,811,911,1011）下方的一个或两个底电极（512,612,730,812,912,1012）；所述底电极（512,612,730,812,912,1012）下方的柔性基底（520,620,750,820,920,1020）；其中，所述两个顶电极（510,610,710,810,910,1010）之间的间隙的下方不具有所述压电层（511,611,720,811,911,1011）。

Description

柔性基底薄膜体声波滤波器的连接结构 技术领域
本发明涉及半导体技术领域，特别地涉及一种柔性基底薄膜体声波滤波器的连接结构。
背景技术
滤波器是现代通信系统中最常用到的一种电学组件之一。根据功能对滤波器进行划分，主要可分为低通、高通、带通和带阻滤波器等。与此同时，柔性电子也迅速发展。至今，柔性电子在显示、传感、通信等领域已有较快发展，可穿戴式柔性电子消费吸引了越来越多的兴趣。柔性电子通常被认为是建立在柔性衬底之上的电子或电子系统，系统具有可弯曲、拉伸和扭曲等特点。与常规硬质基底上电子系统相比，柔性电子需要在发生柔性形变时仍保留有一定的工作能力。在高通信效率应用中，构建柔性射频系统可进一步扩展柔性应用领域。
滤波器在组成形式上有多种分类，其中梯形(Ladder)拓扑结构是较为常见的一种。如图1所示，Ladder结构的各级分别由一个等效的串联谐振器(Series Resonator)Xi(i＝1,2,3…)和一个等效的并联谐振器(Shunt Resonator)Yi(i＝1,2,3…)组成，并联的谐振频率低于串联的谐振频率。滤波器可看作一个二端口网络，图1中Port 1和Port 2分别为信号输入端和输出端。通常，两个谐振器又包括两个谐振点：频率较低的串联谐振点和频率较高的并联谐振点。以带通滤波器为例，在Ladder结构的滤波器中往往令并联谐振器的并联谐振点与串联谐振器的串联谐振点相等以获得性能更佳的滤波器，如图2所示。
另一方面，柔性电子的发展对柔性电学组件的开发提出了更高要求。通信射频波段在未来柔性电子系统中占有重要分量。柔性功能的 实现一定程度上依赖于器件的可柔性化设计。近年来，体声波(BulkAcousticWave，BAW)谐振器获得了快速发展。BAW谐振器凭借简单的结构、高性能、低功耗、小体积等优势成为实现柔性电子系统的重要组件之一。以一种体声波谐振器薄膜体声波谐振器(Film Bulk Acoustic Resonator，FBAR)为例，该类型谐振器具有三明治结构，从上至下依次为顶电极(Top Electrode，TE)、压电层(Piezoelectric Layer，PZ)和底电极(Bottom Electrode，BE)，在外加射频电压下可产生电学谐振。此外，为了构成有效的声反射层，通常还需要在两电极之外构建空气腔或布拉格反射层。硬质基底上的BAW谐振器及其扩展滤波器应用在商业化方面已趋于成熟，但如果将其工艺直接照搬到柔性滤波器上，器件柔性还是不够理想。
例如，两个无电学链接的相邻谐振器的电路示意图见图3a，现有技术器件结构剖图见图3b，包括顶电极310、压电层311、底电极312和柔性衬底320，其中柔性衬底320的顶部表面具有和顶电极对准的空腔330。由于压电层311通常是脆性材料，器件的柔韧性不够理想。
又例如，顶电极隔离型串并联结构的相邻谐振器的电路示意图见图4a，现有技术器件结构剖图见图4b，包括顶电极410、压电层411、底电极412和柔性衬底420，其中柔性衬底420的顶部表面具有和顶电极对准的空腔430。由于压电层411通常是脆性材料，器件的柔韧性不够理想。
发明内容
有鉴于此，本发明提供一种柔性基底薄膜体声波滤波器的连接结构，有利于提高器件的柔韧性。
本发明提出的柔性基底薄膜体声波滤波器的连接结构包括：第一顶电极和第二顶电极，二者之间具有间隙；所述第一顶电极和第二顶电极下方的压电层；所述压电层下方的一个或两个底电极；所述底电 极下方的柔性基底；其中，所述两个顶电极之间的间隙的下方不具有所述压电层。
可选地，所述底电极为第一底电极和第二底电极，分别对应于所述第一顶电极和第二顶电极；所述第一底电极与所述第二顶电极之间经由导电薄膜连接，该导电薄膜位于所述间隙及所述间隙的下方。
可选地，所述导电薄膜上方填充有柔性材料。
可选地，所述间隙下方的不具有所述压电层的位置处，填充有柔性材料。
可选地，所述间隙以及该间隙下方的不具有所述压电层的位置处，填充有柔性材料，其中，所述柔性材料覆盖所述顶电极的边沿。
可选地，所述柔性材料为环氧树脂或聚对二甲苯。
可选地，所述柔性基底的材料包括：聚对苯二甲酸类塑料、聚乙酰亚胺、聚萘二甲酸乙二醇酯或聚醚酰亚胺。
可选地，所述柔性基底顶表面具有两个空腔，并且所述两个空腔分别与所述第一顶电极和所述第二顶电极位置对准。
可选地，所述柔性基底与所述底电极之间具有布拉格反射层。
可选地，所述布拉格反射层是先另行制备后转移到所述柔性衬底之上的。
可选地，所述压电层的材料包括：氮化铝、氧化锌、锆钛酸铅压电陶瓷或聚偏氟乙烯。
根据本发明的技术方案，由于在两个顶电极之间的间隙的下方不具有脆性的压电材料，所以器件具有柔韧性良好的优点。
附图说明
附图用于更好地理解本发明，不构成对本发明的不当限定。其中：
图1是滤波器的梯形(Ladder)拓扑结构的电路图；
图2是谐振单元和滤波器的性能示意图；
图3a是两个无电学链接的相邻谐振器的电路示意图，图3b是现有技术两个无电学链接的相邻谐振器的器件结构剖图；
图4a是顶电极隔离型串并联结构的相邻谐振器的电路示意图，图4b是现有技术顶电极隔离型谐振器的器件结构剖图；
图5是本发明实施例的两个无电学链接的相邻谐振器的器件结构剖图；
图6是本发明实施例的顶电极隔离型串并联结构的相邻谐振器的器件结构剖图；
图7a为本发明实施例的顶电极底电极串联跨接型结构的相邻谐振器的电路图，图7b为图7a对应的一种器件结构剖图，图7c为图7a对应的另一种器件结构剖图；
图8为本发明实施例的两个顶电极的间隙下方的不具有所述压电层的位置处填充柔性材料的器件结构剖图；
图9为本发明实施例的两个顶电极的间隙以及间隙下方的不具有所述压电层的位置处填充柔性材料的器件结构剖图；
图10为本发明实施例的具有布拉格反射层的两个相邻谐振器的器件结构剖图。
具体实施方式
下面详细描述本发明的实施例，所述实施例的示例在附图中示出，其中自始至终相同或类似的标号表示相同或类似的元件或具有相同或类似功能的元件。下面通过参考附图描述的实施例是示例性的，旨在 用于解释本发明，而不能理解为对本发明的限制。
在本发明的描述中，需要理解的是，术语“中心”、“纵向”、“横向”、“长度”、“宽度”、“厚度”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”“内”、“外”、“顺时针”、“逆时针”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本发明和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本发明的限制。
此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个该特征。在本发明的描述中，“多个”的含义是两个或两个以上，除非另有明确具体的限定。
在本发明中，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”、“固定”等术语应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是机械连接，也可以是电连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本发明中的具体含义。
在本发明中，除非另有明确的规定和限定，第一特征在第二特征之“上”或之“下”可以包括第一和第二特征直接接触，也可以包括第一和第二特征不是直接接触而是通过它们之间的另外的特征接触。而且，第一特征在第二特征“之上”、“上方”和“上面”包括第一特征在第二特征正上方和斜上方，或仅仅表示第一特征水平高度高于第二特征。第一特征在第二特征“之下”、“下方”和“下面”包括第一特征在第二特征正下方和斜下方，或仅仅表示第一特征水平高度 小于第二特征。
本发明实施例的柔性基底薄膜体声波滤波器的连接结构，包括：第一顶电极和第二顶电极，二者之间具有间隙；第一顶电极和第二顶电极下方的压电层；压电层下方的一个或两个底电极；底电极下方的柔性基底；其中，两个顶电极之间的间隙的下方不具有压电层。具体地可以结合例1和例2进行说明。
例1
图5为本发明实施例的两个无电学连接谐振器的结构剖图(其电路图对应图3a)。如图5所示，该结构包括顶电极510、压电层511、底电极512和柔性衬底520，其中柔性衬底520的顶部表面可以具有和顶电极对准的空腔530。两顶电极510间隙处可以没有压电层以减小弯曲时该处所受应力，从而获得更好的柔性弯曲性能。需要说明的是，图5所示的器件的制造工艺为：不带衬底的滤波器通过MEMS工艺首先被制造出来，其次，在柔性衬底上刻蚀出空腔，然后通过转移方法将器件与空腔对准并转移固定到柔性衬底上。本文中其他具有带空腔的柔性衬底的器件的制造工艺类似，不再赘述。
例2
图6为本发明实施例的TE隔离型串并联结构谐振器的结构剖图(其电路图对应图4a)。如图6所示，该结构包括顶电极610、压电层611、底电极612和柔性衬底620，其中柔性衬底620的顶部表面可以具有和顶电极对准的空腔630。两顶电极610间隙处可以没有压电层以减小弯曲时该处所受应力，从而获得更好的柔性弯曲性能。
可选地，本发明实施例的柔性基底薄膜体声波滤波器的连接结构中，底电极为第一底电极和第二底电极，分别对应于第一顶电极和第二顶电极；第一底电极与第二顶电极之间经由导电薄膜连接，该导电薄膜位于间隙及间隙的下方。需要说明的是，连接电极的导电薄膜上 方还可以填充有柔性材料。具体地可以结合例3进行说明。
例3
图7a为顶电极底电极串联跨接型结构的相邻谐振器的电路图，图7b为图7a对应的一种器件结构剖图。如图7b所示，该结构包括：顶电极710、压电层720、底电极730、导电薄膜740和柔性衬底750，其中柔性衬底720的顶部表面可以具有和顶电极对准的空腔770。本实施例中，左侧谐振器的底电极通过导电薄膜跨接到右侧谐振器的顶电极，右侧谐振器预定义的顶电极和底电极被交换。其中，形成导电薄膜740可以通过现有工艺实现，例如结合光刻等工艺，采用磁控溅射等方法将材料沉积在目标区域上。
另外，图7c为图7a对应的另一种器件结构剖图。如图7c所示，导电薄膜740上方的空隙上填充柔性材料760以获得更高的机械稳定性。本实施例中，填充的柔性材料包括但不限于环氧树脂(例如基于环氧SU-8树脂的光刻胶)或聚对二甲苯。
可选地，本发明实施例的柔性基底薄膜体声波滤波器的连接结构中，间隙下方的不具有压电层的位置处，填充有柔性材料；具体地可以结合例4进行说明。
例4
图8，结构包括相邻两个顶电极810、压电层811、底电极812、柔性衬底820，其中柔性衬底820的顶部表面可以具有和顶电极对准的空腔830。两个顶电极810之间的间隙中填充有柔性材料860。
可选地，本发明实施例的柔性基底薄膜体声波滤波器的连接结构中，间隙以及该间隙下方的不具有压电层的位置处，填充有柔性材料，其中，柔性材料覆盖顶电极的边沿，这样可以有效地防止顶电极起翘。具体地可以结合例5进行说明。
例5
图9所示，结构包括相邻两个顶电极910、压电层911、底电极912、柔性衬底920，其中柔性衬底920的顶部表面可以具有和顶电极对准的空腔930。两个顶电极910之间的间隙中填充有柔性材料960。
可选地，本发明实施例的柔性基底薄膜体声波滤波器的连接结构中，柔性基底与底电极之间具有布拉格反射层。布拉格反射层和器件通过MEMS工艺首先被制造出来。其次，通过转移方法直接将器件转移并固定到柔性衬底上。布拉格反射层是由多层声阻抗不同的材料交叉堆叠得到的(低声阻抗材料-高声阻抗材料-低声阻抗材料-高声阻抗材料如此交叉堆叠)，通过多次有效反射抑制声能泄漏。布拉格反射结构一般至少4层，层数也可以更多。常见的低声阻抗材料有二氧化硅(SiO 2)、金属铝(Al)等，常见的高声阻抗材料有金属钼(Mo)、钨(W)等，同一个布拉格反射层中，低/高声阻抗材料不限于一种材料，可以是这些材料的混合使用。具体地可以结合例6进行说明。
例6
图10，结构包括相邻两个顶电极1010、压电层1011、底电极1012、柔性衬底1020，其中底电极1012和柔性衬底1020之间具有交叉堆叠的两层低声阻抗材料1030和高声阻抗材料1031。
需要说明的是，本发明所有实施例中的柔性材料可以为环氧树脂或聚对二甲苯；柔性基底的材料包括但不限于聚对苯二甲酸类塑料(PET)，聚乙酰亚胺(PI)，聚萘二甲酸乙二醇酯(PEN)，聚醚酰亚胺(PEI)等。
压电层的材料包括但不限于氮化铝(AlN)、氧化锌(ZnO)、锆钛酸铅压电陶瓷(PZT)以及聚偏氟乙烯(PVDF)等，也可以是掺杂了其它元素的以上材料。上述材料为压电薄膜，厚度小于10微米。氮化铝薄膜为多晶形态或者单晶形态，生长方式为薄膜溅射(sputtering)或者有机 金属化学气相沉积法(MOCVD)。
由上可知，通过本发明实施例的柔性基底薄膜体声波滤波器的连接结构，通过减少两个顶电极间隙间的脆性的压电材料，增强了器件的柔性。
上述具体实施方式，并不构成对本发明保护范围的限制。本领域技术人员应该明白的是，取决于设计要求和其他因素，可以发生各种各样的修改、组合、子组合和替代。任何在本发明的精神和原则之内所作的修改、等同替换和改进等，均应包含在本发明保护范围之内。

Claims (11)

  1. 一种柔性基底薄膜体声波滤波器的连接结构，其特征在于，包括：
    第一顶电极和第二顶电极，二者之间具有间隙；
    所述第一顶电极和第二顶电极下方的压电层；
    所述压电层下方的一个或两个底电极；
    所述底电极下方的柔性基底；
    其中，所述两个顶电极之间的间隙的下方不具有所述压电层。
  2. 根据权利要求1所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，
    所述底电极为第一底电极和第二底电极，分别对应于所述第一顶电极和第二顶电极；
    所述第一底电极与所述第二顶电极之间经由导电薄膜连接，该导电薄膜位于所述间隙及所述间隙的下方。
  3. 根据权利要求2所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述导电薄膜上方填充有柔性材料。
  4. 根据权利要求1所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述间隙下方的不具有所述压电层的位置处，填充有柔性材料。
  5. 根据权利要求1所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述间隙以及该间隙下方的不具有所述压电层的位置处，填充有柔性材料，其中，所述柔性材料覆盖所述顶电极的边沿。
  6. 根据权利要求3至5中任一项所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述柔性材料为环氧树脂或聚对二甲苯。
  7. 根据权利要求1所述柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述柔性基底的材料包括：聚对苯二甲酸类塑料、聚乙酰亚胺、聚萘二甲酸乙二醇酯或聚醚酰亚胺。
  8. 根据权利要求1所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述柔性基底顶表面具有两个空腔，并且所述两个空腔分别与所述第一顶电极和所述第二顶电极位置对准。
  9. 根据权利要求1所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述柔性基底与所述底电极之间具有布拉格反射层。
  10. 根据权利要求9所述的柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述布拉格反射层是先另行制备后转移到所述柔性衬底之上的。
  11. 根据权利要求1所述柔性基底薄膜体声波滤波器的连接结构，其特征在于，所述压电层的材料包括：氮化铝、氧化锌、锆钛酸铅压电陶瓷或聚偏氟乙烯。
PCT/CN2018/124073 2018-12-26 2018-12-26 柔性基底薄膜体声波滤波器的连接结构 Ceased WO2020132993A1 (zh)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11136074A (ja) * 1997-10-28 1999-05-21 Kyocera Corp 積層型圧電共振子およびラダー型フィルタ
CN102075161A (zh) * 2011-01-20 2011-05-25 张�浩 声波器件及其制作方法
CN107196618A (zh) * 2017-02-16 2017-09-22 杭州左蓝微电子技术有限公司 薄膜体声波谐振器及其制备方法
CN108092639A (zh) * 2017-12-21 2018-05-29 华南理工大学 一种微纳米柱柔性阵列薄膜体声波谐振子滤波器及其制备

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11136074A (ja) * 1997-10-28 1999-05-21 Kyocera Corp 積層型圧電共振子およびラダー型フィルタ
CN102075161A (zh) * 2011-01-20 2011-05-25 张�浩 声波器件及其制作方法
CN107196618A (zh) * 2017-02-16 2017-09-22 杭州左蓝微电子技术有限公司 薄膜体声波谐振器及其制备方法
CN108092639A (zh) * 2017-12-21 2018-05-29 华南理工大学 一种微纳米柱柔性阵列薄膜体声波谐振子滤波器及其制备

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