CN111010112B - Resonator with partially filled gap of step structure, filter and electronic device - Google Patents
Resonator with partially filled gap of step structure, filter and electronic device Download PDFInfo
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- CN111010112B CN111010112B CN201910480623.6A CN201910480623A CN111010112B CN 111010112 B CN111010112 B CN 111010112B CN 201910480623 A CN201910480623 A CN 201910480623A CN 111010112 B CN111010112 B CN 111010112B
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Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/02007—Details of bulk acoustic wave devices
- H03H9/02015—Characteristics of piezoelectric layers, e.g. cutting angles
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/02007—Details of bulk acoustic wave devices
- H03H9/02047—Treatment of substrates
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
- H03H9/56—Monolithic crystal filters
- H03H9/564—Monolithic crystal filters implemented with thin-film techniques
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
- H03H9/58—Multiple crystal filters
- H03H9/582—Multiple crystal filters implemented with thin-film techniques
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
The invention relates to a bulk acoustic wave resonator comprising: a substrate; an acoustic mirror; a bottom electrode disposed over the substrate; a top electrode facing the bottom electrode and having an electrode connection portion; and a piezoelectric layer disposed over the bottom electrode and between the bottom electrode and the top electrode, wherein: the edge of the top electrode is provided with a suspension wing structure and/or a bridge part structure, and a gap is arranged below the suspension wing structure and/or the bridge part structure; the resonator also includes a filler layer that fills only a portion of the void. The invention also relates to a filter with the bulk acoustic wave resonator and an electronic device with the filter.
Description
Technical Field
Embodiments of the present invention relate to the field of semiconductors, and more particularly, to a bulk acoustic wave resonator, a filter having the resonator, and an electronic apparatus having the filter.
Background
The film bulk wave resonator manufactured by utilizing the longitudinal resonance of the piezoelectric film in the thickness direction has become a viable substitute for the surface acoustic wave device and the quartz crystal resonator in the aspects of mobile phone communication, high-speed serial data application and the like. The rf front-end bulk wave filter/diplexer provides superior filtering characteristics such as low insertion loss, steep transition bands, greater power capacity, and greater anti-electrostatic discharge (ESD) capability. The high-frequency film bulk wave oscillator with ultralow frequency temperature drift has low phase noise, low power consumption and wide bandwidth modulation range. In addition, these micro thin film resonators use CMOS compatible processing on silicon substrates, which can reduce unit cost and facilitate final integration with CMOS circuitry.
Bulk wave resonators comprise an acoustic mirror and two electrodes, and a layer of piezoelectric material, called piezoelectric excitation, between the two electrodes. The bottom and top electrodes, also called excitation electrodes, function to cause mechanical oscillations of the resonator layers. The acoustic mirror forms an acoustic isolation between the bulk wave resonator and the substrate to prevent acoustic waves from being conducted out of the resonator, causing energy loss.
Ideally, the energy of the alternating electrical signal applied to the upper bottom electrode is solely converted into acoustic energy of the longitudinal vibration mode (also commonly referred to as piston mode) of the piezoelectric layer. In practice, however, acoustic waves of transverse modes are also generated along with longitudinal modes of vibration, the presence of which attenuate the energy of the acoustic waves of the piston mode, thus reducing the performance parameters critical to the device, such as the quality factor (Q) and the effective electromechanical coupling coefficient (k 2 t,eff ) Causing serious deterioration. At the same time, the filter performance constructed from bulk acoustic wave resonators is also degraded.
In a conventional bulk acoustic wave resonator, a suspended wing structure is provided at the edge of the top electrode, which helps suppress acoustic waves of the transverse vibration mode.
Fig. 1 is a schematic top view of a prior art thin film bulk acoustic resonator, fig. 2 is a schematic cross-sectional view of a prior art resonator based on the section 1B-1B in fig. 1, and fig. 3 is a schematic cross-sectional view of another prior art resonator based on the section 1B-1B in fig. 1. In fig. 1 to 3, the bulk acoustic wave resonator includes a substrate 101, an acoustic mirror 103, a first electrode 105, a piezoelectric layer 107, a second electrode 109, a single step structure (or a suspended wing structure) 113, a protrusion structure 115, and a void 111. The void 111 may be air or entirely filled with a dielectric material.
However, there is still a need in practical applications to further suppress the sound wave of the transverse vibration mode to increase the parallel resonance impedance Rp of the resonator, thereby increasing the Q value of the resonator.
Disclosure of Invention
The present invention has been made to alleviate or solve at least one of the above-mentioned problems of the prior art.
According to an aspect of an embodiment of the present invention, there is provided a bulk acoustic wave resonator including:
a substrate;
an acoustic mirror;
a bottom electrode disposed over the substrate;
a top electrode facing the bottom electrode and having an electrode connection portion; and
a piezoelectric layer disposed over the bottom electrode and between the bottom electrode and the top electrode,
wherein:
the edge of the top electrode is provided with a suspension wing structure and/or a bridge part structure, and a gap is arranged below the suspension wing structure and/or the bridge part structure;
the resonator also includes a filler layer that fills only a portion of the void.
Optionally, the filler layer fills a portion of the void under the wing structure or bridge structure.
Optionally, the edge of the top electrode is provided with a suspension wing structure and a bridge structure; the filler layer fills a portion of the void under the wing structure and the bridge structure.
Optionally, the filling layer is formed of a dielectric material.
Optionally, the filling layer fills an inner portion of the void; or the filling layer fills the middle portion of the void.
Optionally, the ratio r of the width of the filling layer to the width of the gap is in the range of: 0.2< r <1. Further, the ratio r of the width of the filling layer to the width of the void is in the range of 0.25 to 0.75, optionally the ratio of the width of the filling layer to the width of the void is in the range of 0.4 to 0.6.
Optionally, the resonator further comprises a protruding structure located on the upper side of the suspended wing structure and/or bridge structure. Further, the protruding structure has a base protruding portion in contact with the top electrode and an extension portion extending over the cantilever structure and/or bridge structure. Further, the width of the base projection is in the range of 0.2 μm to 10 μm, and still further, in the range of 0.75 μm to 6 μm.
Optionally, the resonator further comprises a protruding structure located below the suspended wing structure and/or bridge structure, the void being formed below the protruding structure.
Optionally, the suspension wing structure is a multi-step structure, and/or the inner side of the bridge structure is a multi-step structure, the gap is formed below the multi-step structure, and the gap is a step gap. Further optionally, the filling layer fills the innermost level void.
Optionally, the multi-step structure includes a first step connected to the top electrode and a second step connected to the first step. Optionally, the first step has a void height of 50A-500A. Optionally, the second step has a void height of 500A-4000A. Alternatively, the width of the first step is 0.2-7 μm and the width of the second step is 0.2-7 μm.
Optionally, the resonator includes a protruding structure disposed over the multi-step structure.
Optionally, the resonator includes a protruding structure disposed below the multi-step structure.
According to another aspect of an embodiment of the present invention, a filter is provided that includes the bulk acoustic wave resonator described above.
According to a further aspect of the embodiments of the present invention, an electronic device is provided, including the filter described above.
Drawings
These and other features and advantages of the various embodiments of the disclosed invention will be better understood from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate like parts throughout the several views, and wherein:
FIG. 1 is a schematic top view of a prior art thin film bulk acoustic resonator;
FIG. 2 is a schematic cross-sectional view of a prior art resonator taken along line 1B-1B of FIG. 1;
FIG. 3 is a schematic cross-sectional view of another prior art resonator taken on the basis of 1B-1B in FIG. 1;
FIG. 4 is a schematic top view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention;
FIG. 5 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 2B-2B in FIG. 4, according to an exemplary embodiment of the present invention;
FIG. 6 is an enlarged view of a portion of the wing portion of FIG. 5;
FIG. 7 is a graph illustrating the relationship between the ratio of void fill width to void overall width and the Rp value of the resonator and the base width of the protruding structure in the structure of FIG. 6;
fig. 8 is a graph exemplarily showing a relationship between a ratio of a gap filling width to a total width of a gap and an Rp value of a resonator in the structure in fig. 6, in a case where a base width of the protruding structure is not changed (to 1 μm);
FIG. 9 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 2B-2B in FIG. 4, according to another exemplary embodiment of the present invention;
fig. 10 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention, in which a filling portion is provided at a middle portion of a void;
fig. 11 is a schematic top view of a bulk acoustic wave resonator according to yet another exemplary embodiment of the invention;
FIG. 12 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 3B-3B in FIG. 11, with a protrusion structure above a suspended wing structure, according to an exemplary embodiment of the present invention;
FIG. 13 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 3B-3B in FIG. 11, with a protrusion structure below a suspended wing structure, according to an exemplary embodiment of the present invention;
fig. 14 is a schematic partial cross-sectional view of a double step cantilever structure of a top electrode of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention;
fig. 15 is a schematic top view of a bulk acoustic wave resonator according to yet another exemplary embodiment of the invention;
FIG. 16 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 4B-4B in FIG. 15, with a protrusion structure above a bridge structure, according to an exemplary embodiment of the present invention;
FIG. 17 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 4B-4B in FIG. 15, with a protrusion structure below a bridge structure, according to an exemplary embodiment of the present invention;
fig. 18 is a schematic top view of a bulk acoustic wave resonator according to yet another exemplary embodiment of the invention;
FIG. 19 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 5B-5B in FIG. 18, with a protrusion structure over a suspended wing structure and a bridge structure, according to an exemplary embodiment of the invention;
fig. 20 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention, taken along line 5B-5B in fig. 18, wherein the protruding structures are below the suspended wing structure and the bridge structure.
Detailed Description
The technical scheme of the invention is further specifically described below through examples and with reference to the accompanying drawings. The following description of embodiments of the present invention with reference to the accompanying drawings is intended to illustrate the general inventive concept and should not be taken as limiting the invention.
A bulk acoustic wave resonator according to an embodiment of the present invention is described below with reference to fig. 4-10.
Fig. 4 is a schematic top view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention. Fig. 5 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 2B-2B in fig. 4, according to an exemplary embodiment of the present invention. Fig. 6 is an enlarged view of a portion of the hanging wing portion of fig. 5.
In fig. 4 to 6, the bulk acoustic wave resonator includes a substrate 201, an acoustic mirror 203, a first electrode 205, a piezoelectric layer 207, a second electrode 209, a single step structure (or a suspended wing structure) 213, a protruding structure 215, a void portion 211, and a filling portion 217.
In the example of fig. 4-6, a fill portion 217 and a void portion 211 are included below the single step structure 213. In other words, in the present invention, the void under the step structure is not completely filled by the filling portion.
As shown in fig. 5-6, the protruding structure 215 has a base protruding portion (section W1 in fig. 6) in contact with the top electrode and an extending portion (section W in fig. 6) extending over the cantilever structure.
In alternative embodiments, the width of the base protrusions is in the range of 0.2 μm to 10 μm, such as 0.5 μm, 1 μm, 1.5 μm and 10 μm, and still further, in the range of 0.75 μm-6 μm, but may be, for example, 1 μm, in addition to the end values.
As shown in fig. 6, h is the distance between the single step 213 and the piezoelectric layer 207, W is the width of the single step structure 213 (the width of the gap corresponding to the entire gap formed by the single step structure), W1 is the width of the portion (the base protrusion) of the bump structure 215 located only on the second electrode 209, and W2 is the width of the filling portion 217.
Fig. 7 is a graph exemplarily showing a relationship between a ratio of a gap filling width to a total width of the gap and Rp values of the resonator and a base width of the protrusion structure in the structure of fig. 6. r=w2/W in fig. 7 is defined, that is, the ratio of the filling portion to the entire void width. Simulations were performed for different filling ratios, setting h=1000a, w=1um, and the parallel resonance impedance Rp as a function of W1 is shown in fig. 7. It can be seen that with partial filling, the parallel resonant impedance Rp is better than without filling. When W1 is within a specific range, the effect of partial filling is better than full filling.
Fig. 8 is a graph exemplarily showing a relationship between a ratio of a gap filling width to a total width of the gap and an Rp value of the resonator in the structure in fig. 6, in a case where a base width of the protrusion structure is not changed (to 1 μm). In fig. 8, w1=1 um, that is, the region a in fig. 8, is set, and the parallel resonance impedance Rp varies with r as shown in fig. 8.
As shown in fig. 8, when r=0.5, i.e., half is filled, rp= 4534.1 increases by about 472.2 (about 12%) compared to no filling. About 296.4 (about 7%) increased compared to full fill. The range of r can be 0.2< r <1.
Fig. 9 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 2B-2B in fig. 4, according to another exemplary embodiment of the present invention. As shown in fig. 9, the protrusion structure 215 is disposed under the single step structure 213, and the filling portion 217 fills a portion of the void.
In the above embodiments, the filling layers each fill the innermost side of the void, but the present invention is not limited thereto, and in the present invention, the filling layers may be provided outside the void, and may be provided in the middle portion of the void (i.e., with gaps on both sides of the filling layer). Fig. 10 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention, in which a filling portion is provided at a middle portion of a void. The reference numerals in fig. 10 are the same as in fig. 5. Fig. 11 is a schematic top view of a bulk acoustic wave resonator according to still another exemplary embodiment of the present invention, fig. 12 is a schematic cross-sectional view of the bulk acoustic wave resonator taken along line 3B-3B in fig. 11, in which a protrusion structure is above a suspended wing structure, and fig. 13 is a schematic cross-sectional view of the bulk acoustic wave resonator taken along line 3B-3B in fig. 11, in which the protrusion structure is below the suspended wing structure, according to an exemplary embodiment of the present invention.
In fig. 11 to 13, the bulk acoustic wave resonator includes a substrate 301, an acoustic mirror 303, a first electrode 305, a piezoelectric layer 307, a second electrode 309, a two-step structure (or a suspended wing structure) 313, a protruding structure 315, a void portion 311, and a filling portion 317.
The embodiment shown in fig. 11-13 differs from the embodiment of fig. 4-10 in that in fig. 11-13 the suspended wing structure of the top electrode is a double step structure, rather than the single step structure of the previous embodiments.
Fig. 14 is a partial cross-sectional schematic view of a double step cantilever structure of a top electrode of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention. In fig. 14, 307 is a piezoelectric layer, 309 is a top electrode, and 311 is a void. Referring to fig. 14, the first step 313a has a void height h1 of 50A-500A, which may be 200A in addition to the above-mentioned end points; the void height h2 of the second step 313b may be 500A-4000A, for example, 500A,2000A or 4000A. In fig. 14, the width W1 of the first step is 0.2 to 7 μm, and the width W2 of the second step is 0.2 to 7 μm, for example, both may be 5 μm.
Referring to fig. 12 and 14, the filling layer 317 fills the innermost level void. It should be noted here that, in the case where the overhang wing structure or the bridge structure mentioned later is provided with the projection structure on the inner side thereof, the step gap is a step gap under the projection structure.
It should also be noted that in the present invention, the void under the wing structure and/or bridge structure refers to the void under the wing structure and/or bridge structure (including in the case where the protruding structure is provided) when not filled with the filling layer in the present invention. The width of the gap, whether it is a bridge structure or a wing structure, is the width of the portion of the gap that falls within the effective region of the resonator in the thickness direction of the resonator.
It should be noted that in the present invention, the side close to the active area of the resonator is the inner side, and vice versa.
It should be noted that in fig. 12-14, the protruding structures may also cover only a portion of the wing structure.
Fig. 15 is a schematic top view of a bulk acoustic wave resonator according to yet another exemplary embodiment of the invention;
FIG. 16 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 4B-4B in FIG. 15, with a protrusion structure 416 above a bridge structure 414, according to an exemplary embodiment of the invention; fig. 17 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention, taken along line 4B-4B in fig. 15, wherein the protrusion structure 416 is below the bridge structure 414, and the bridge structure in fig. 17 has a multi-step structure.
In fig. 15 to 17, the bulk acoustic wave resonator includes a substrate 401, an acoustic mirror 403, a first electrode 405, a piezoelectric layer 407, a second electrode 409, a bridge structure 414, a protrusion structure 416, a void portion 412, and a filling portion 418.
Referring to fig. 16 and 17, the filler layer 418 fills the innermost side of the void.
It is noted that in fig. 16-17, the protruding structures may also cover only a part of the bridge structure.
Fig. 18 is a schematic top view of a bulk acoustic wave resonator according to yet another exemplary embodiment of the invention;
FIG. 19 is a schematic cross-sectional view of a bulk acoustic wave resonator taken along line 5B-5B in FIG. 18, with a protrusion structure over a suspended wing structure and a bridge structure, according to an exemplary embodiment of the invention; fig. 18 is a schematic cross-sectional view of a bulk acoustic wave resonator according to an exemplary embodiment of the present invention, taken along line 5B-5B in fig. 18, wherein the protruding structures are below the suspended wing structure and the bridge structure.
In fig. 18 to 20, the bulk acoustic wave resonator includes a substrate 501, an acoustic mirror 503, a first electrode 505, a piezoelectric layer 507, a second electrode 509, a suspended wing structure 513, a bridge structure 514, a protrusion structure 515, a protrusion structure 516, a void portion 511, a void portion 512, a filling portion 517, and a filling portion 518.
In fig. 19, the bridge structure and the wing structure are both single-step structures. In fig. 20, the bridge structure and the wing structure are both multi-step structures. As can be appreciated by those skilled in the art, one of the bridge structure and the wing structure may be a multi-step structure.
Referring to fig. 19 and 20, the filling layer fills the innermost side of the void.
It is also noted that, although in the above embodiments, the filling layers each fill the innermost side of the void, the present invention is not limited thereto, and in the present invention, the filling layers may be provided outside the void, and may be provided in the middle portion of the void (i.e., with gaps on both sides of the filling layer).
It should be noted that in the embodiments of the present invention, although the thin film bulk acoustic resonator is described as an example, these descriptions can be applied to other types of bulk acoustic resonators.
In the present invention, the respective constituent parts and materials are described as follows:
the top electrode and the bottom electrode are made of metal materials, wherein the materials can be molybdenum, ruthenium, gold, aluminum, magnesium, tungsten, copper, titanium, iridium, osmium, chromium or the composite or alloy of the above metals.
Filling portions, optionally of a non-metallic dielectric material, such as: silicon dioxide, silicon nitride, silicon carbide, aluminum nitride, magnesium oxide, aluminum oxide, or other metal oxides or nitrides or polymers, and the like.
Passivation layer: the layer is an optional protective layer that prevents moisture, oxygen or other foreign substances from attacking the resonator. The protective layer may be a non-metallic material such as silicon dioxide, silicon nitride, silicon carbide, aluminum nitride, magnesium oxide, aluminum oxide, or other metal oxides or nitrides or polymers, etc.
Piezoelectric layer: aluminum nitride, doped aluminum nitride, zinc oxide, lead zirconate titanate, lithium niobate, quartz, potassium niobate or lithium tantalate, wherein the doped ALN contains at least one rare earth element such as scandium, yttrium, lanthanum, erbium, ytterbium, and the like.
Based on the above, the present invention proposes a bulk acoustic wave resonator including:
a substrate;
an acoustic mirror;
a bottom electrode disposed over the substrate;
a top electrode facing the bottom electrode and having an electrode connection portion; and
a piezoelectric layer disposed over the bottom electrode and between the bottom electrode and the top electrode,
wherein:
the edge of the top electrode is provided with a suspension wing structure and/or a bridge part structure, and a gap is arranged below the suspension wing structure and/or the bridge part structure; and is also provided with
The resonator also includes a filler layer that fills only a portion of the void.
The filling layer may fill an inner portion of the void; or the filling layer fills the middle portion of the void.
Based on the above, the invention also provides a filter comprising a plurality of bulk acoustic wave resonators. The invention also provides electronic equipment comprising the filter or the bulk acoustic wave resonator.
Although embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
Claims (23)
1. A bulk acoustic wave resonator comprising:
a substrate;
an acoustic mirror;
a bottom electrode disposed over the substrate;
a top electrode facing the bottom electrode and having an electrode connection portion; and
a piezoelectric layer disposed over the bottom electrode and between the bottom electrode and the top electrode,
wherein:
the edge of the top electrode is provided with a suspension wing structure and/or a bridge part structure, and a gap is arranged below the suspension wing structure and/or the bridge part structure;
the resonator further includes a filling layer filling only a portion of the void;
the resonator further includes a protrusion structure provided at a position corresponding to the cantilever structure or the bridge structure; and is also provided with
The inner end of the protruding structure is located inside the inner end of the filling layer and/or the outer end of the protruding structure is located outside the outer end of the filling layer.
2. The resonator of claim 1, wherein:
the filler layer fills a portion of the void under the wing structure or bridge structure.
3. The resonator of claim 1, wherein:
the edge of the top electrode is provided with a suspension wing structure and a bridge structure;
the filler layer fills a portion of the void under the wing structure and the bridge structure.
4. The resonator of claim 1, wherein:
the filler layer is formed of a dielectric material.
5. The resonator according to any of claims 1-4, wherein:
the filling layer fills an inner portion of the void; or alternatively
The filling layer fills a middle portion of the void.
6. The resonator of claim 5, wherein:
the ratio r of the width of the filling layer to the width of the gap is in the range of: 0.2< r <1.
7. The resonator of claim 6, wherein:
the ratio r of the width of the filling layer to the width of the void is in the range of 0.25 to 0.75.
8. The resonator of claim 7, wherein:
the ratio of the width of the filling layer to the width of the void is in the range of 0.4 to 0.6.
9. The resonator according to any of claims 1-4, wherein:
the resonator further comprises a protruding structure at the upper side of the suspended wing structure and/or bridge structure.
10. The resonator of claim 9, wherein:
the protruding structure has a base protruding portion in contact with the top electrode and an extension portion extending over the cantilever structure and/or bridge structure.
11. The resonator of claim 10, wherein:
the width of the base protrusion is in the range of 0.2 μm to 10 μm.
12. The resonator of claim 11, wherein:
the width of the base protrusions is in the range of 0.75 μm to 6 μm.
13. The resonator according to any of claims 1-4, wherein:
the resonator further comprises a protruding structure located below the suspended wing structure and/or bridge structure, the void being formed below the protruding structure.
14. The resonator according to any of claims 1-4, wherein:
the suspended wing structure is a multi-step structure, and/or the inner side of the bridge part structure is a multi-step structure, the gap is formed below the multi-step structure, and the gap is a step gap.
15. The resonator of claim 14, wherein:
the filling layer fills the innermost level void.
16. The resonator of claim 14, wherein:
the multi-step structure comprises a first step connected with the top electrode and a second step connected with the first step.
17. The resonator of claim 16, wherein:
the first step has a void height of 50A-500A.
18. The resonator of claim 17, wherein:
the second step has a void height of 500A-4000A.
19. The resonator of claim 18, wherein:
the width of the first step is 0.2-7 μm and the width of the second step is 0.2-7 μm.
20. The resonator of claim 14, wherein:
the resonator includes a protruding structure disposed over a multi-step structure.
21. The resonator of claim 14, wherein:
the resonator includes a protruding structure disposed below the multi-step structure.
22. A filter comprising a bulk acoustic wave resonator according to any of claims 1-21.
23. An electronic device comprising a filter according to claim 22 or a bulk acoustic wave resonator according to any of claims 1-21.
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| CN201910480623.6A CN111010112B (en) | 2019-06-04 | 2019-06-04 | Resonator with partially filled gap of step structure, filter and electronic device |
| PCT/CN2020/076213 WO2020244254A1 (en) | 2019-06-04 | 2020-02-21 | Resonator with gap of step structure being partially filled, and filter and electronic device |
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| CN201910480623.6A CN111010112B (en) | 2019-06-04 | 2019-06-04 | Resonator with partially filled gap of step structure, filter and electronic device |
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| CN115250104A (en) * | 2021-04-27 | 2022-10-28 | 诺思(天津)微系统有限责任公司 | Bulk acoustic wave resonator, filter, and electronic device |
| CN114006595B (en) * | 2021-12-30 | 2022-03-29 | 深圳新声半导体有限公司 | Bulk acoustic wave resonator and bulk acoustic wave filter |
| CN118100840A (en) * | 2024-03-11 | 2024-05-28 | 睿思微系统(烟台)有限公司 | Preparation method of bulk acoustic wave resonator and bulk acoustic wave resonator |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101908865A (en) * | 2010-08-20 | 2010-12-08 | 庞慰 | Body wave resonator and processing method thereof |
| CN102811031A (en) * | 2011-06-02 | 2012-12-05 | 安华高科技无线Ip（新加坡）私人有限公司 | Film bulk acoustic resonator comprising a bridge |
| CN106533385A (en) * | 2015-09-11 | 2017-03-22 | 三星电机株式会社 | Acoustic wave resonator and filter including the same |
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| US8692631B2 (en) * | 2009-10-12 | 2014-04-08 | Hao Zhang | Bulk acoustic wave resonator and method of fabricating same |
| US9219464B2 (en) * | 2009-11-25 | 2015-12-22 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Bulk acoustic wave (BAW) resonator structure having an electrode with a cantilevered portion and a piezoelectric layer with multiple dopants |
| US9571064B2 (en) * | 2011-02-28 | 2017-02-14 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Acoustic resonator device with at least one air-ring and frame |
| CN105680813B (en) * | 2016-02-25 | 2018-12-07 | 锐迪科微电子（上海）有限公司 | A kind of thin film bulk acoustic wave resonator and its manufacturing method |
| US10903814B2 (en) * | 2016-11-30 | 2021-01-26 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave resonator |
| US11271543B2 (en) * | 2018-02-13 | 2022-03-08 | Samsung Electro-Mechanics Co., Ltd. | Bulk acoustic wave resonator |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101908865A (en) * | 2010-08-20 | 2010-12-08 | 庞慰 | Body wave resonator and processing method thereof |
| CN102811031A (en) * | 2011-06-02 | 2012-12-05 | 安华高科技无线Ip（新加坡）私人有限公司 | Film bulk acoustic resonator comprising a bridge |
| CN106533385A (en) * | 2015-09-11 | 2017-03-22 | 三星电机株式会社 | Acoustic wave resonator and filter including the same |
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