WO2024040696A1 - 一种谐振器、滤波器、电子设备、及谐振器的制备方法 - Google Patents
一种谐振器、滤波器、电子设备、及谐振器的制备方法 Download PDFInfo
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Classifications
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- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
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- H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
- H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
- H03H9/171—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type
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- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
- H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
- H03H9/171—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type
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- 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
- H03H2003/021—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 the resonators or networks being of the air-gap type
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- H03H2003/023—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 the resonators or networks being of the membrane type
Definitions
- the filter has the function of improving the transmitting and receiving signals, and plays a decisive role in the RF front-end module.
- the filter which is composed of multiple resonators connected in a topological network structure, meets the high standards of RF front-end modules because of its small size, strong integration capability, high quality factor at high frequencies, and strong power tolerance. Therefore, the preparation of high-performance resonators has become one of the hot research topics today.
- the basic structure of the resonator is a top electrode, a bottom electrode, and a piezoelectric layer sandwiched between the top and bottom electrodes.
- the upper surface of the top electrode is in contact with the air, causing total reflection of sound waves at the interface between the top electrode and the air to suppress energy leakage.
- a sound wave reflection structure is provided below the bottom electrode to prevent energy from leaking to the substrate and being stored in the resonator.
- the overlapping area of the top electrode, piezoelectric layer, bottom electrode, and acoustic reflection structure forms the effective area of the resonator.
- Resonators are divided into air gap resonators (FBAR, film bulk acoustic resonator) and solid mounted resonators (SMR, solidly mounted resonator) according to different sound wave reflection structures.
- FBAR air gap resonators
- SMR solid mounted resonators
- the sound wave reflection structure of FBAR is a cavity
- the SMR is a Bragg reflector.
- the cavities of the air-gap resonator include different locations, including underground cavities embedded in the substrate and above-ground cavities located on the surface of the substrate.
- a sacrificial layer needs to be formed first, and then an etching method is used above the sacrificial layer to at least penetrate the piezoelectric layer to form a release hole.
- the corrosive solution contacts the sacrificial layer through the release hole to remove the sacrificial layer, thereby forming Cavity. If the relief hole is placed inside the resonator, the effective area will be lost. Therefore, arranging the release hole on the periphery of the resonator can ensure the effective area.
- part of the cavity needs to protrude outward.
- the protruding part of the cavity (such as the release channel position in Figure 1, and position B in Figure 2) will cause a stress mutation in the piezoelectric layer covering it, affecting the piezoelectric performance near the effective area and the reliability of the cavity structure.
- the cavity is prone to mechanical fracture at the mutation point.
- the object of the present invention is to provide an electronic device, a filter, a resonator and a preparation method of the resonator, which can effectively reduce the stress change of the piezoelectric layer.
- the present invention provides a resonator, including: a substrate, a bottom electrode, a piezoelectric layer and a top electrode.
- the bottom electrode is located between the substrate and the piezoelectric layer.
- the electrical layer is located between the bottom electrode and the top electrode. It is characterized in that a multi-layer cavity is provided between the bottom electrode and the substrate, and the width of the multi-layer cavity is farther away from the substrate. gradually decreases in the bottom direction.
- the multiple layers of cavities include a first cavity close to the substrate and a second cavity close to the bottom electrode, and the first cavity surrounds the second cavity.
- the shape of the first cavity is different from the shape of the second cavity.
- a partial area of the first cavity protrudes outward in a direction parallel to the substrate to form a release channel, so that the shape of the first cavity is different from the shape of the second cavity.
- the first cavity includes a plurality of corners, and at least one of the corners protrudes outward in a direction parallel to the substrate to form a release channel.
- a release hole is provided in the piezoelectric layer above the release channel for connecting the outside world with the release channel and for releasing the sacrificial layer in the cavity.
- the corners are in arc shape or angle shape.
- the side surfaces of the multi-layer cavities are inclined, arc-shaped or stepped.
- the side surfaces of the multiple layers of cavities are inclined and have the same inclination angle.
- the edge of the cavity close to the bottom electrode is retracted by 1 ⁇ m to 10 ⁇ m relative to the edge of the cavity close to the substrate.
- the height of the cavity close to the substrate is greater than the height of the cavity close to the bottom electrode.
- the present invention also provides a filter, including the resonator mentioned above.
- the present invention also provides an electronic device, including the resonator mentioned above.
- the invention also provides a method for preparing a resonator, which method includes:
- a multi-layer cavity is formed between the substrate and the bottom electrode, and the width of the multi-layer cavity gradually decreases in a direction away from the substrate.
- the method of forming multiple layers of the cavity includes first forming multiple sacrificial layers between the substrate and the bottom electrode, and then removing the sacrificial layer after the top electrode is formed. Multiple layers of said sacrificial layer.
- the material of the sacrificial layer closest to the substrate is the same as or different from the materials of the other sacrificial layers.
- the sacrificial layer includes a material doped with phosphorus element.
- the phosphorus content of the sacrificial layer closest to the substrate is higher than that of the remaining sacrificial layers, and the release rate of the sacrificial layer closest to the substrate is higher than that of the remaining sacrificial layers. release speed.
- the invention provides a resonator, which has the following beneficial effects:
- the width of the multi-layer cavity gradually decreases, and the piezoelectric layer covers the multi-layer cavity, causing the morphology of the piezoelectric layer at the edge of the effective area to slowly change, reducing the resistance of the piezoelectric layer.
- the sudden change in morphology reduces the sudden change in stress and improves the piezoelectric performance of the piezoelectric layer.
- the present invention also provides a filter, electronic equipment and preparation method using the above resonator. Therefore, the filter, electronic equipment and preparation method also have the above beneficial effects, which will not be described again here.
- Figure 1 is a top view of an air gap resonator provided by an embodiment of the background technology
- Figure 2 is a cross-sectional view in the A’-A’ direction of Figure 1;
- Figure 3 is a top view of a resonator provided by an embodiment of the present invention.
- Figure 4 is a cross-sectional view along the A-A direction of Figure 3;
- 5 to 9 are schematic structural diagrams of a method for manufacturing a resonator provided by embodiments of the present invention.
- orientation descriptions such as up, down, front, back, left, right, etc., are based on the orientation or position relationships shown in the drawings and are only In order to facilitate the description of the present invention and simplify the description, it is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as a limitation of the present invention.
- the core of the present invention is to provide an electronic device, a filter, a resonator and a preparation method of the resonator, which can effectively reduce the stress change of the piezoelectric layer.
- the inclination s of the side of the cavity is negatively correlated with the width w of the cavity, that is, when the inclination is smaller, the piezoelectric
- the width w is constant
- the slope s is positively correlated with the height h. That is, the smaller the slope, the smaller the change in the piezoelectric layer morphology and the smaller the stress mutation.
- the smaller the cavity height when the resonator resonates , there is a risk of adhesion between the resonant film and the substrate.
- the stress distribution of the film layer will be uneven, which will lead to energy loss or eardrum problems, which will greatly reduce the performance of the device or even damage the device, especially for devices above 2.5GHz.
- uneven stress distribution in the film layer will lead to reduced resonator performance, lower yield, or reliability problems.
- Figure 3 is a top view of a resonator provided by an embodiment of the present invention
- Figure 4 is a cross-sectional view of Figure 3 in the A-A direction
- Figures 5 to 9 are embodiments of the present invention Provided is a structural schematic diagram of a method for preparing a resonator.
- An embodiment of the present invention provides a resonator, including: a substrate 100, a bottom electrode 300, a piezoelectric layer 400 and a top electrode 500.
- the bottom electrode 300 is located between the substrate 100 and the piezoelectric layer 400
- the piezoelectric layer 400 is located between the bottom electrode 300 and the top electrode 500 .
- a multi-layer cavity is provided between the bottom electrode 300 and the substrate 100 , and the width of the multi-layer cavity gradually decreases in the direction away from the substrate 100 .
- the bottom electrode 300 covers the upper surface of the multilayer cavity and extends to the substrate 100, forming a cavity above the substrate 100, with the side surfaces of the bottom electrode 300 serving as a part of the cavity.
- the piezoelectric layer 400 covers the multilayer cavity and the bottom electrode 300 and extends to the substrate 100 at both ends. In a direction parallel to the substrate 100, the thickness of the piezoelectric layer 400 is substantially unchanged.
- the top electrode 500 is located on the piezoelectric layer 400, and at least one end thereof is inside the edge of the cavity. For example, the non-connected end of the top electrode 500 that is not connected to the outside is inside the edge of the cavity, so as to avoid the top electrode 500, the piezoelectric layer 400 and the bottom electrode 300 overlap to generate additional parasitic oscillations.
- the present invention sets the above-ground cavity into a multi-layer cavity, and the width of each cavity gradually decreases from the direction close to the substrate 100 to the direction away from the substrate 100, so that the subsequent growth on the multi-layer cavity
- the morphological change of the bottom electrode 300 and the piezoelectric layer 400 decreases at the intersection of each layer of cavity. For example, at the edge of the effective area, that is, at position C, the piezoelectric layer 400 changes from one large morphological change to multiple morphological changes. After minor morphological changes, the morphology of the bottom electrode 300 and the piezoelectric layer 400 slowly changes on the edge of the multi-layer cavity, thereby reducing large stress changes caused by large morphological changes. At the same time, the slower morphology changes improve the growth quality of the bottom electrode 300 and the piezoelectric layer 400, reduce growth defects, and increase the Q value of the device.
- a partial area of the cavity closest to the substrate 100 protrudes outward to form a release channel 420, and a release hole 410 is provided in the piezoelectric layer 400 above the release channel 420, and the release solution enters through the release hole and the release channel.
- the sacrificial layer 600 in the cavity reacts with it to release the sacrificial layer 600 in the cavity to form a cavity.
- the height of the release channel 420 is the height of the cavity closest to the substrate 100.
- the height of the release channel 420 is reduced so that the layer closest to the substrate 100 is covered.
- the morphological changes of the piezoelectric layer 400 on the cavity are reduced, and the stress mutation is also reduced.
- the multi-layer cavity at least includes a first cavity 210 close to the substrate 100 and a second cavity 220 close to the bottom electrode 300 .
- the first cavity 210 surrounds Second cavity 220. Since the first cavity 210 protrudes outward in a direction parallel to the substrate 100 to form more than one release channel 420, the shape of the first cavity 210 is different from the shapes of other layer cavities due to the protruding portion.
- the shape of at least one layer of cavities is different from the shapes of other layers, and the shapes of other layers can be set to be the same or different.
- the multi-layer cavity may be a regular polygon or an irregular polygon, which is not specifically limited in this embodiment.
- the first cavity 210 has a plurality of corners, and at least one corner protrudes outward in a direction parallel to the substrate 100 to form a release channel 420 .
- other layer cavities also have multiple corners. In order to reduce sudden changes in stress, the corners are designed into arcs or angles, such as right angles.
- the release channel 420 can be disposed at the corner of the second cavity 220 , and certainly can be disposed at a position that does not correspond to the corner of the second cavity 220 . This embodiment does not make a specific limit.
- the number of the release channel 420 is at least In order to speed up the release of the sacrificial layer 600, multiple release channels 420 can be provided.
- the sides of the multi-layer cavity are inclined, arc-shaped or stepped.
- the inclination angles of the multi-layer cavities can be the same or different. Adaptable selection can be made according to actual stress conditions.
- the height setting of the multi-layer cavity can be in any proportion.
- the edge of the cavity close to the bottom electrode 300 is retracted by 1 ⁇ m to 10 ⁇ m relative to the edge of the cavity close to the substrate 100 .
- the height of the cavity near the substrate 100 is greater than the height of the cavity near the bottom electrode 300 to facilitate the release of the sacrificial layer 600 .
- the existing technology usually chooses to set it near the outer periphery of the cavity, for example, setting the release hole 410 on the side of the slope of the sacrificial layer 600.
- the release hole 410 is close to the effective area, which will destroy the stress distribution in the effective area and cause the effective area to be damaged.
- the variation range of piezoelectricity becomes larger, which affects the device yield.
- processing the release hole 410 on the side requires high process, which increases the process cost.
- the release hole 410 designed in the present invention is provided above the platform between the first cavity 210 and the second cavity 220 instead of on the slope, which facilitates processing and has low process requirements.
- the following uses a two-layer cavity as an example.
- the second cavity 220 is approximately pentagonal.
- the first cavity 210 is at the periphery of the second cavity 220 , and five release channels 420 are respectively protruded outward at the five corners corresponding to the second cavity 220 .
- a release hole 410 is provided above the release channel 420 .
- the first cavity 210 is about 1 ⁇ m to 10 ⁇ m wider than the second cavity 220, preferably 3 ⁇ m.
- the height h1 of the first cavity 210 is greater than the height h2 of the second cavity 220 to reduce the stress mutation of the piezoelectric layer 400 at the edge of the effective area.
- h1 may also be equal to or less than h2. In this embodiment without further qualification.
- the width w1 of the release channel 420 (as shown in FIG. 3 ) is above 15 ⁇ m, and the diameter of the release hole 410 is approximately within 20 ⁇ m, preferably 10 ⁇ m.
- the inclination angles of the edges of the two-layer cavities can be the same, such as 30° or 45°, or they can be different, such as 15° for the upper cavity and 30° for the lower cavity, or other arbitrary values set according to actual applications.
- the present invention also provides a filter including the above resonator.
- the present invention also provides an electronic device, including the above resonator.
- the core of the present invention lies in the above-mentioned resonator.
- the filter and other structures in the electronic device provided in this embodiment, reference can be made to the relevant prior art and will not be described in detail here.
- the present invention also provides a method for preparing a resonator.
- the preparation method includes:
- Step 1 As shown in Figure 5, a substrate 100 is provided, and a sacrificial layer 600 is covered on the upper surface of the substrate 100.
- the sacrificial layer 600 is patterned by etching.
- the sacrificial layer 600 is at least two layers, one close to the substrate 100. A portion of the sacrificial layer 600 protrudes outward;
- Step 2 As shown in Figure 6, a bottom electrode 300 is formed on the surface of the patterned sacrificial layer 600 and the substrate 100. A part of the bottom electrode 300 is located above the protruding part. At the non-protruding part, the bottom electrode 300 covers the sacrificial layer. 600 surface and extending onto the substrate 100;
- a piezoelectric layer 400 is formed on the surface of the bottom electrode 300.
- the piezoelectric layer 400 covers the sacrificial layer 600 and the bottom electrode 300 and extends to the substrate 100;
- Step 4 grow a top electrode 500 on the surface of the piezoelectric layer 400, and etch the top electrode 500 so that the non-connected end of the top electrode 500 is inside the edge of the sacrificial layer 600 to be formed into a cavity;
- Step 5 As shown in Figure 9, above the protruding part of the sacrificial layer 600, the piezoelectric layer 400 is etched to the sacrificial layer 600 to form a release hole 410, and the sacrificial layer 600 is released.
- the protruding part forms a release channel 420, and a release channel 420 is formed at the bottom.
- a multi-layer cavity is formed between the electrode 300 and the substrate 100. At this time, the width of the multi-layer cavity gradually decreases in the direction away from the substrate 100.
- the material of the sacrificial layer 600 closest to the substrate 100 is the same as or different from the materials of the other sacrificial layers 600 .
- the sacrificial layer 600 at least includes a material doped with phosphorus element.
- the material of the sacrificial layer 600 may also include metals such as Ge, Sb, Ti, Al, Cu, etc., phosphate silicate glass (PSG) or polymers, preferably phosphorus-doped SiO 2 (PSG); in other cases, the sacrificial layer 600 It can also be Si, Poly (polycrystalline silicon) or other dielectric materials, or a combination of metal materials and dielectric materials. Dielectric or metal can be realized through CVD, PVD, evaporation and other processes.
- the release speed of the sacrificial layer 600 closest to the substrate 100 is higher than the release speed close to the bottom electrode 300.
- common metals such as Ti and Al are disposed on the sacrificial layer 600 close to the substrate and can quickly dissolve in hydrogen fluoride.
- the acid achieves the release effect or the phosphorus content of the sacrificial layer 600 closest to the substrate 100 is higher than that of the other sacrificial layers 600 , so that the release speed of the sacrificial layer 600 closest to the substrate 100 is higher than that of the other sacrificial layers 600 .
- the release speed of the sacrificial layer 600 close to the bottom electrode 300 can be made slower to reduce stress.
- the substrate 100 material may be silicon (Si), sapphire (sapphire), polycrystalline silicon (poly), silicon dioxide (SiO 2 ), gallium arsenide (GaAs), spinel, Glass or ceramic material, preferably silicon (Si).
- the material of the bottom electrode 300 may be gold (Au), molybdenum (Mo), ruthenium (Ru), aluminum (Al), platinum (Pt), titanium (Ti), tungsten (W), palladium (Pd), chromium (Cr) ), nickel (Ni), etc., preferably molybdenum (Mo).
- the material of the piezoelectric layer 400 may be zinc oxide (ZnO), zinc sulfide (ZnS), aluminum nitride (AlN), cadmium sulfide (CdS), lead titanate [PT] (PbTiO 3 ), lead zirconate titanate [PZT] (Pb(Zr,Ti)O 3 ), lithium tantalate (LiTaO 3 ), lithium niobate (LiNbO 3 ) or other members of the lanthanum lead zirconate titanate series, preferably aluminum nitride (AlN) .
- the material of the top electrode 500 and the bottom electrode 300 may be the same or different, and may be gold (Au), molybdenum (Mo), ruthenium (Ru), aluminum (Al), platinum (Pt), titanium (Ti), tungsten ( W), palladium (Pd), chromium (Cr), nickel (Ni), etc.
- the top electrode 500 and the bottom electrode 300 are made of the same material, which is molybdenum (Mo).
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Abstract
本案提供的一种谐振器,包括衬底、底电极、压电层和顶电极,底电极位于衬底和压电层之间,压电层位于底电极和顶电极之间,底电极与衬底之间设置有多层空腔,从靠近衬底到远离衬底的方向上,每一层空腔的宽度逐渐减小,使后续在多层空腔上生长的底电极和压电层在每层空腔的交接处形貌变化减小,从而减少因形貌变化较大而产生的较大应力变化。同时,较缓慢的形貌变化,使得底电极和压电层的生长质量得到提高,减少生长缺陷,提高器件Q值。另外,由于释放通道的高度即为最靠近衬底的一层空腔的高度,其高度相对降低,使得覆盖在最靠近衬底的一层空腔上的压电层形貌变化减小,应力突变也减小。本案还提供一种滤波器、电子设备、及谐振器的制备方法。
Description
本申请要求于2022年8月25日提交中国专利局、申请号为202211024843.6、发明名称为“一种谐振器、滤波器、电子设备、及谐振器的制备方法”的国内申请的优先权,其全部内容通过引用结合在本申请中。
随着电磁频谱的日益拥挤、无线通讯设备频段与功能的不断增加、以及无线通讯电磁频谱从500MHz到5GHz以上的高速增长,人们对性能高、成本低、功耗低、体积小的射频前端模块的需求与日俱增。滤波器作为射频前端模块之一,具有改善发射和接收信号的功能,在射频前端模块中发挥着举足轻重的作用。
由多个谐振器以拓扑网络结构连接组成的滤波器,因具有体积小、集成能力强、高频下仍具有高品质因子和功率承受能力强等特点而满足了射频前端模块的高标准。因而,高性能谐振器的制备成为如今的热门研究之一。
谐振器的基本结构是顶电极、底电极以及夹在顶、底电极间的压电层。顶电极上表面与空气接触使得声波在顶电极与空气交界处发生全反射而抑制能量泄露,与此同时在底电极下方设置声波反射结构使得能量不至于泄露到衬底并储存在谐振器内。顶电极、压电层、底电极以及声波反射结构的重叠区域形成谐振器的有效区域。
谐振器根据声波反射结构的不同,分为气隙型谐振器(FBAR,film bulk acoustic resonator)和固体装配型谐振器(SMR,solidly mounted resonator)。FBAR的声波反射结构是空腔,SMR则是布拉格反射镜。其中气隙型谐振器的空腔根据位置不同,包括嵌入衬底内的地下型空腔和位于衬底表面的地上型空腔。
如图1和图2所示,对于地上型空腔,由于空腔侧面为倾斜状,当保证空腔高度的前提下,受刻蚀工艺限制,该倾斜侧面的角度较大,导致随后在倾斜侧边上生长的底电极以及压电层膜层发生较大的形貌变化,从而产生较大的应力突变,容易产生较大的裂缝和缺陷。
另外,空腔在制作时,需要先形成牺牲层,再在牺牲层上方采用刻蚀方法至少穿透压电层形成释放孔,腐蚀药液通过释放孔与牺牲层接触以去除牺牲层,从而形成空腔。释放孔如果设置在谐振器内部,则会损失有效区域面积。因此,将释放孔设置在谐振器***,可以保证有效区域面积,但是为了形成释放孔,空腔的部分区域需向外凸出,空腔的凸出部分(例如图1中的释放通道位置,以及图2中的B位置)会使其上覆盖的压电层产生应力突变,影响有效区域附近的压电性能和空腔结构的可靠性,空腔容易在突变处发生机械断裂问题。
因此,在具有地上型空腔的器件中,如何降低压电层应力变化,是本领域技术人员亟待解决的问题。
发明内容
本发明的目的在于提供一种电子设备、滤波器、谐振器及谐振器的制备方法,可有效降低压电层应力变化。
为解决上述技术问题,本发明提供一种谐振器,包括:衬底、底电极、压电层和顶电极,所述底电极位于所述衬底和所述压电层之间,所述压电层位于所述底电极和所述顶电极之间,其特征在于,所述底电极与所述衬底之间设置有多层空腔,多层所述空腔的宽度在远离所述衬底方向上逐渐减小。
可选的,在上述谐振器中,多层所述空腔包括靠近衬底的第一空腔和靠近底电极的第二空腔,所述第一空腔包围第二空腔。
可选的,在上述谐振器中,所述第一空腔的形状与第二空腔形状不同。
可选的,在上述谐振器中,所述第一空腔的部分区域沿平行于衬底的方向向外凸出形成释放通道,使得第一空腔形状与第二空腔形状不同。
可选的,在上述谐振器中,所述第一空腔包括多个拐角,至少一个所述拐角沿平行于衬底的方向向外凸出形成释放通道。
可选的,在上述谐振器中,所述释放通道上方的压电层中设置有用于连通外界与所述释放通道的释放孔,用于释放空腔内的牺牲层。
可选的,在上述谐振器中,所述拐角呈弧形或角度形。
可选的,在上述谐振器中,多层所述空腔的侧面呈倾斜状、弧形或阶梯状。
可选的,在上述谐振器中,多层所述空腔的侧面呈倾斜状且倾斜角度相同。
可选的,在上述谐振器中,靠近所述底电极的空腔边缘相对于靠近所述衬底的空腔边缘内缩1μm~10μm。
可选的,在上述谐振器中,靠近所述衬底的空腔的高度大于靠近所述 底电极的空腔的高度。
本发明还提供一种滤波器,包括上文所述的谐振器。
本发明还提供一种电子设备,包括上文所述的谐振器。
本发明还提供一种谐振器的制备方法,所述制备方法包括:
提供衬底;
在所述衬底上形成底电极;
在所述底电极上形成压电层;
在所述压电层上形成顶电极;
其中,在所述衬底和所述底电极之间形成多层空腔,多层所述空腔的宽度在远离所述衬底方向上逐渐减小。
可选的,在上述制备方法中,多层所述空腔的形成方法包括,先在所述衬底和所述底电极之间形成多层牺牲层,待所述顶电极形成之后,再去除多层所述牺牲层。
可选的,在上述制备方法中,最靠近所述衬底的牺牲层的材料与其余层牺牲层的材料相同或不同。
可选的,在上述制备方法中,所述牺牲层包括掺杂磷元素的材料。
可选的,在上述制备方法中,最靠近所述衬底的牺牲层的磷的含量高于其余牺牲层的磷的含量,最靠近所述衬底的牺牲层的释放速度高于其余牺牲层的释放速度。
本发明提供了一种谐振器,其有益效果在于:
1、从衬底向顶电极方向,多层空腔的宽度逐渐减小,压电层覆盖在多层空腔上,使得有效区域边缘的压电层形貌缓慢变化,减小压电层的形貌 突变,减小应力突变,提高压电层的压电性能。
2、由于释放通道的高度降低,覆盖在释放通道上方的压电层在释放通道边缘的形貌突变减小,从而减小应力突变。同时提高了器件结构的机械稳定性。
本发明还提供一种应用上述谐振器的滤波器、电子设备及制备方法,因此,滤波器、电子设备及制备方法同样具有上述有益效果,此处便不再赘述。
为了更清楚地说明本发明实施例或现有技术中的技术方案,下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍,显而易见地,下面描述中的附图仅仅是本发明的实施例,对于本领域普通技术人员来讲,在不付出创造性劳动的前提下,还可以根据提供的附图获得其他的附图。
图1为背景技术实施例提供的一种气隙型谐振器的俯视图;
图2为图1在A’-A’向的截面图;
图3为本发明实施例提供的一种谐振器的俯视图;
图4为图3在A-A向的截面图;
图5~9为本发明实施例提供的一种谐振器的制备方法的结构示意图。
图1~图2中:
S100-衬底;S200-空腔;S300-底电极;S400-压电层;S410-释放孔;S420-释放通道;S500-顶电极;
图3~图9中:
100-衬底;210-第一空腔;220-第二空腔;300-底电极;400-压电层;410-释放孔;420-释放通道;500-顶电极;600-牺牲层;B-压电层形貌;C-压电层的有效区域边缘。
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,仅用于解释本发明,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,涉及到方位描述,例如上、下、前、后、左、右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。
在本发明的描述中,多个的含义是两个以上,如果有描述到第一、第二只是用于区分技术特征为目的,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或者隐含指明所指示的技术特征的先后关系。
本发明的描述中,除非另有明确的限定,设置、安装、连接等词语应做广义理解,所属技术领域技术人员可以结合技术方案的具体内容合理确定上述词语在本发明中的具体含义。
本发明的核心是提供一种电子设备、滤波器、谐振器及谐振器的制备方法,可有效降低压电层应力变化。
为了使本领域的技术人员更好地理解本发明提供的技术方案,下面将结合附图和具体实施例对本发明作进一步的详细说明。
参照背景技术中图1和图2所示的常规谐振器,当空腔的高度h一定时,空腔侧面的倾斜度s与空腔的宽度w呈负相关,即当倾斜度越小,压电层形貌变化越小,应力突变也较小,但空腔越宽,谐振器的尺寸也增大,这不利于谐振器的小尺寸化。而当宽度w一定时,倾斜度s与高度h呈正相关,即倾斜度越小,压电层形貌变化越小,应力突变也较小,但空腔高度越小,在谐振器发生谐振时,会有发生谐振薄膜与衬底粘连的风险。
而当压电层形貌变化较大,应力突变较大,会产生膜层应力分布不均,从而导致能量损耗或鼓膜等问题,进而使器件性能大大降低甚至损坏器件,尤其对于2.5GHz以上的高频频段器件,膜层应力分布不均将导致谐振器性能降低、良率较低或者可靠性出现问题。
所以为了减小有效区域边缘的压电层的应力突变,在保证空腔的高度h和宽度w固定不变时,减小倾斜度s,是减小应力突变的一种方式。
基于上述分析,如图3-图9所示,图3为本发明实施例提供的一种谐振器的俯视图;图4为图3在A-A向的截面图;图5~9为本发明实施例提供的一种谐振器的制备方法的结构示意图。
本发明实施例提供的一种谐振器,包括:衬底100、底电极300、压电层400和顶电极500。其中,底电极300位于衬底100和压电层400之间,压电层400位于底电极300和顶电极500之间。
特别的,底电极300与衬底100之间设置有多层空腔,多层空腔的宽度在远离衬底100方向上逐渐减小。底电极300覆盖多层空腔的上表面且延伸 至衬底100上,在衬底100上方围成空腔,底电极300的侧面作为空腔的一部分。压电层400覆盖多层空腔和底电极300且两端延伸至衬底100上,在平行于衬底100的方向上,压电层400的厚度基本不变。顶电极500位于压电层400上,其至少一个末端在空腔的边缘内侧,例如顶电极500不与外部进行连接的非连接端在空腔的边缘内侧,以避免顶电极500、压电层400和底电极300三者重叠产生额外的寄生振荡。
本发明将地上型空腔设置为多层空腔,且从靠近衬底100到远离衬底100的方向上,每一层空腔的宽度逐渐减小,使得后续在多层空腔上生长的底电极300和压电层400在每层空腔的交接处形貌变化减小,例如在有效区域的边缘,即在C位置,压电层400由一次较大形貌变化,转变为由多次较小的形貌变化,底电极300和压电层400在多层空腔的边缘上形貌缓慢变化,从而减少因形貌变化较大而产生的较大应力变化。同时,较缓慢的形貌变化,使得底电极300和压电层400的生长质量得到提高,减少生长缺陷,提高器件Q值。
另外,最靠近衬底100的一层空腔的部分区域向外凸出形成释放通道420,并且在释放通道420上方的压电层400内设置释放孔410,释放溶液通过释放孔和释放通道进入空腔内的牺牲层600与之接触反应,以释放空腔内的牺牲层600形成空腔。此时释放通道420的高度即为最靠近衬底100的一层空腔的高度,相对于整体多层空腔的高度,释放通道420的高度降低,使得覆盖在最靠近衬底100的一层空腔上的压电层400形貌变化减小,应力突变也减小。同时,可以保证谐振区域的有效面积最大化,同时提高了释放通道420的布局灵活度,方便谐振器连接时的设计布局。
在一具体实施例中,如图3和图4所示,多层空腔至少包括靠近衬底100的第一空腔210以及靠近底电极300的第二空腔220,第一空腔210包围第二空腔220。由于第一空腔210沿平行于衬底100的方向向外凸出形成1个以上的释放通道420,使得第一空腔210的形状因为凸出部分与其他层空腔的形状不同。
可以理解为,至少有一层空腔(即最靠近衬底100的一层空腔)的形状和其他层的形状不同,其他层的形状可以设置成相同或不同。
多层空腔可以为规则多边形,还可以是不规则多边形,本实施例不作具体限定。在一种形式中,第一空腔210具有多个拐角,至少一个拐角沿平行于衬底100的方向向外凸出形成释放通道420。除第一空腔210外的其他层空腔也具有多个拐角。为了减小应力突变,拐角设计成弧形或角度形,例如直角形。
需要说明的是,释放通道420可以设置在第二空腔220的拐角处,当然可以设置在不与第二空腔220拐角对应的位置,本实施例不作具体限定,释放通道420的个数至少是1个,为了加快牺牲层600的释放,可以设置多个释放通道420。
多层空腔的侧面呈倾斜状、弧形或阶梯状。多层空腔的倾斜角度可以相同,也可以不同。可根据实际应力情况进行适应性的选择。多层空腔的高度设置可以是任意比例。优选情况下,为了实现较优的应力变化,靠近底电极300的空腔边缘相对于靠近衬底100的空腔边缘内缩1μm~10μm。靠近衬底100的空腔的高度大于靠近底电极300的空腔的高度,以便于牺牲层600的释放。
现有技术通常选择在空腔的外周附近设置,例如在牺牲层600的斜坡上的侧面上设置释放孔410,释放孔410离有效区域较近,会破坏有效区域的应力分布,导致有效区域的压电性变化范围变大,影响器件良率。另外在侧面加工释放孔410对工艺要求较高,提升了工艺成本。而,本发明设计的释放孔410是在第一空腔210和第二空腔220之间的平台上方设置释放孔,而非斜坡上,便于加工,对工艺要求不高。
下面以两层空腔作为示例说明。第二空腔220近似于五边形,第一空腔210在第二空腔220的***,且在对应于第二空腔220的5个拐角处分别向外凸出形成5个释放通道420,释放通道420上方设置释放孔410。
第一空腔210比第二空腔220宽约1μm~10μm,优选3μm。第一空腔210的高度h1大于第二空腔220的高度h2,以减小压电层400在有效区域边缘的应力突变,在其他实施例中,h1也可以等于或者小于h2,本实施例不作进一步限定。
释放通道420的宽度w1(如图3所示)在15μm以上,释放孔410的直径约为20μm以内,优选10μm。
两层空腔边缘的倾斜角度可以相同,比如同为30°或者45°,也可以不同,比如上方空腔为15°,下方空腔为30°,或者是其他根据实际应用设置的任意数值。
此外,本发明还提供一种滤波器,包括上文的谐振器。本发明还提供一种电子设备,包括上文的谐振器。
其中,应当理解的是,本发明的核心在于上述谐振器,对于本实施例提供的滤波器和电子设备中的其他结构,可参考相关现有技术,此处便不再细述。
请参照图5-图9,本发明还提供一种谐振器的制备方法,应用如上文的谐振器,制备方法包括:
步骤1、如图5所示,提供衬底100,在衬底100的上表面覆盖牺牲层600,通过刻蚀图案化的牺牲层600,牺牲层600为至少2层,靠近衬底100的一层牺牲层600的一部分向外凸出;
步骤2、如图6所示,在图案化的牺牲层600和衬底100表面形成底电极300,底电极300的一部分位于凸出部分上方,在非凸出部分位置,底电极300覆盖牺牲层600表面并延伸至衬底100上;
步骤3、如图7所示,底电极300表面形成压电层400,压电层400覆盖牺牲层600和底电极300并延伸至衬底100上;
步骤4、如图8所示,压电层400表面生长顶电极500,刻蚀顶电极500,使得顶电极500的非连接末端在待形成空腔的牺牲层600边缘内侧;
步骤5、如图9所示,牺牲层600的凸出部分上方,刻蚀压电层400至牺牲层600形成释放孔410,释放牺牲层600,凸出部分则形成释放通道420,并在底电极300和衬底100之间形成多层空腔,此时多层空腔的宽度在远离衬底100方向上逐渐减小。
在上述制备方法的基础上,最靠近衬底100的牺牲层600的材料与其余层牺牲层600的材料相同或不同。其中,牺牲层600至少包括掺杂磷元素的材料。牺牲层600材料还可以包含Ge、Sb、Ti、Al、Cu等的金属、磷酸硅 酸盐玻璃(PSG)或聚合物,优选掺杂磷的SiO
2(PSG);其他情况下,牺牲层600也可以为Si、Poly(多晶硅)或者其他介质材料,或者是金属材料和介质材料的组合。介质或者金属可以通过CVD、PVD、蒸镀等工艺实现。
进一步地,最靠近衬底100的牺牲层600的释放速度高于靠近底电极300的释放速度,例如常见的Ti、Al等金属设置在靠近衬底的牺牲层600上可以快速的溶于氢氟酸达到释放效果或者,最靠近衬底100的牺牲层600的磷的含量高于其余牺牲层600的磷的含量,使得最靠近衬底100的牺牲层600的释放速度高于其余牺牲层600的释放速度,此时可以使得靠近底电极300的牺牲层600释放速度较慢,减小应力。
在一具体实施例中,衬底100材料可以是硅(Si),蓝宝石(sapphire),多晶硅(poly),二氧化硅(SiO
2),砷化镓(GaAs),尖晶石(spinel),玻璃或陶瓷材料,优选为硅(Si)。底电极300的材料可以是金(Au)、钼(Mo)、钌(Ru)、铝(Al)、铂(Pt)、钛(Ti)、钨(W)、钯(Pd)、铬(Cr)、镍(Ni)等,优选为钼(Mo)。压电层400的材料可以是由氧化锌(ZnO),硫化锌(ZnS),氮化铝(AlN),硫化镉(CdS),钛酸铅[PT](PbTiO
3)、钛酸锆酸铅[PZT](Pb(Zr,Ti)O
3),钽酸锂(LiTaO
3),铌酸锂(LiNbO
3)或锆钛酸铅镧系列的其他成员制成,优选为氮化铝(AlN)。顶电极500的材料与底电极300的材料可以相同或者不同,可以是金(Au)、钼(Mo)、钌(Ru)、铝(Al)、铂(Pt)、钛(Ti)、钨(W)、钯(Pd)、铬(Cr)、镍(Ni)等,优选顶电极500与底电极300材料相同,均为钼(Mo)。
本说明书中各个实施例采用递进的方式描述,每个实施例重点说明的都是与其他实施例的不同之处,各个实施例之间相同相似部分互相参见即 可。
本文中应用了具体个例对本发明的原理及实施方式进行了阐述,以上实施例的说明只是用于帮助理解本发明的方法及其核心思想。应当指出,对于本技术领域的普通技术人员来说,在不脱离本发明原理的前提下,还可以对本发明进行若干改进和修饰,这些改进和修饰也落入本发明权利要求的保护范围内。
Claims (18)
- 一种谐振器,包括:衬底、底电极、压电层和顶电极,所述底电极位于所述衬底和所述压电层之间,所述压电层位于所述底电极和所述顶电极之间,其特征在于,所述底电极与所述衬底之间设置有多层空腔,多层所述空腔的宽度在远离所述衬底方向上逐渐减小。
- 根据权利要求1所述的谐振器,其特征在于,多层所述空腔包括靠近衬底的第一空腔和靠近底电极的第二空腔,所述第一空腔包围第二空腔。
- 根据权利要求2所述的谐振器,其特征在于,所述第一空腔的形状与第二空腔形状不同。
- 根据权利要求3所述的谐振器,其特征在于,所述第一空腔的部分区域沿平行于衬底的方向向外凸出形成释放通道,使得第一空腔形状与第二空腔形状不同。
- 根据权利要求4所述的谐振器,其特征在于,所述第一空腔包括多个拐角,至少一个所述拐角沿平行于衬底的方向向外凸出形成释放通道。
- 根据权利要求4所述的谐振器,其特征在于,所述释放通道上方的压电层中设置有用于连通外界与所述释放通道的释放孔,用于释放空腔内的牺牲层。
- 根据权利要求5所述的谐振器,其特征在于,所述拐角呈弧形或角度形。
- 根据权利要求1所述的谐振器,其特征在于,多层所述空腔的侧面呈倾斜状、弧形或阶梯状。
- 根据权利要求8所述的谐振器,其特征在于,多层所述空腔的侧面 呈倾斜状且倾斜角度相同。
- 根据权利要求1所述的谐振器,其特征在于,靠近所述底电极的空腔边缘相对于靠近所述衬底的空腔边缘内缩1μm~10μm。
- 根据权利要求1所述的谐振器,其特征在于,靠近所述衬底的空腔的高度大于靠近所述底电极的空腔的高度。
- 一种滤波器,其特征在于,包括如权利要求1-11任一项所述的谐振器。
- 一种电子设备,其特征在于,包括如权利要求1-11任一项所述的谐振器。
- 一种谐振器的制备方法,所述制备方法包括:提供衬底;在所述衬底上形成底电极;在所述底电极上形成压电层;在所述压电层上形成顶电极;其特征在于,在所述衬底和所述底电极之间形成多层空腔,多层所述空腔的宽度在远离所述衬底方向上逐渐减小。
- 根据权利要求14所述的制备方法,其特征在于,多层所述空腔的形成方法包括,先在所述衬底和所述底电极之间形成多层牺牲层,待所述顶电极形成之后,再去除多层所述牺牲层。
- 根据权利要求15所述的制备方法,其特征在于,最靠近所述衬底的牺牲层的材料与其余层牺牲层的材料相同或不同。
- 根据权利要求16所述的制备方法,其特征在于,所述牺牲层包括 掺杂磷元素的材料。
- 根据权利要求17所述的制备方法,其特征在于,最靠近所述衬底的牺牲层的磷的含量高于其余牺牲层的磷的含量,最靠近所述衬底的牺牲层的释放速度高于其余牺牲层的释放速度。
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050179508A1 (en) * | 2004-02-18 | 2005-08-18 | Susumu Sato | Thin film bulk acoustic wave resonator and production method of the same |
CN111313859A (zh) * | 2019-11-29 | 2020-06-19 | 天津大学 | 体声波谐振器及其制造方法、滤波器及电子设备 |
CN113346864A (zh) * | 2021-05-28 | 2021-09-03 | 杭州星阖科技有限公司 | 一种体声波谐振器及其制作方法 |
WO2022000809A1 (zh) * | 2020-06-29 | 2022-01-06 | 瑞声声学科技(深圳)有限公司 | 谐振器及其制备方法 |
CN114257198A (zh) * | 2020-09-22 | 2022-03-29 | 诺思(天津)微***有限责任公司 | 具有空隙层的体声波谐振器及组件和制造方法、滤波器和电子设备 |
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Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050179508A1 (en) * | 2004-02-18 | 2005-08-18 | Susumu Sato | Thin film bulk acoustic wave resonator and production method of the same |
CN111313859A (zh) * | 2019-11-29 | 2020-06-19 | 天津大学 | 体声波谐振器及其制造方法、滤波器及电子设备 |
WO2022000809A1 (zh) * | 2020-06-29 | 2022-01-06 | 瑞声声学科技(深圳)有限公司 | 谐振器及其制备方法 |
CN114257198A (zh) * | 2020-09-22 | 2022-03-29 | 诺思(天津)微***有限责任公司 | 具有空隙层的体声波谐振器及组件和制造方法、滤波器和电子设备 |
CN113346864A (zh) * | 2021-05-28 | 2021-09-03 | 杭州星阖科技有限公司 | 一种体声波谐振器及其制作方法 |
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