CN114499442A - Impedance matching device for surface acoustic wave device - Google Patents
Impedance matching device for surface acoustic wave device Download PDFInfo
- Publication number
- CN114499442A CN114499442A CN202210089875.8A CN202210089875A CN114499442A CN 114499442 A CN114499442 A CN 114499442A CN 202210089875 A CN202210089875 A CN 202210089875A CN 114499442 A CN114499442 A CN 114499442A
- Authority
- CN
- China
- Prior art keywords
- electrode
- idt
- acoustic wave
- wave device
- surface acoustic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000010897 surface acoustic wave method Methods 0.000 title claims abstract description 46
- 239000000758 substrate Substances 0.000 claims abstract description 42
- 238000006243 chemical reaction Methods 0.000 claims abstract description 8
- 244000126211 Hericium coralloides Species 0.000 claims description 12
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 239000013078 crystal Substances 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 239000002356 single layer Substances 0.000 claims description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- 229910052804 chromium Inorganic materials 0.000 claims description 3
- 239000011651 chromium Substances 0.000 claims description 3
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 3
- 229910052737 gold Inorganic materials 0.000 claims description 3
- 239000010931 gold Substances 0.000 claims description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 3
- 229910052721 tungsten Inorganic materials 0.000 claims description 3
- 239000010937 tungsten Substances 0.000 claims description 3
- 238000013461 design Methods 0.000 abstract description 13
- 238000003780 insertion Methods 0.000 abstract description 5
- 230000037431 insertion Effects 0.000 abstract description 5
- 239000010410 layer Substances 0.000 description 6
- 238000004891 communication Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- WSMQKESQZFQMFW-UHFFFAOYSA-N 5-methyl-pyrazole-3-carboxylic acid Chemical compound CC1=CC(C(O)=O)=NN1 WSMQKESQZFQMFW-UHFFFAOYSA-N 0.000 description 2
- 239000010432 diamond Substances 0.000 description 2
- 229910003460 diamond Inorganic materials 0.000 description 2
- 230000001788 irregular Effects 0.000 description 2
- GQYHUHYESMUTHG-UHFFFAOYSA-N lithium niobate Chemical compound [Li+].[O-][Nb](=O)=O GQYHUHYESMUTHG-UHFFFAOYSA-N 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 229910003327 LiNbO3 Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 230000001154 acute effect Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
Images
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
- H03H9/02535—Details of surface acoustic wave devices
- H03H9/02543—Characteristics of substrate, 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
- H03H9/02535—Details of surface acoustic wave devices
- H03H9/02637—Details concerning reflective or coupling arrays
- H03H9/02685—Grating lines having particular arrangements
- H03H9/02724—Comb like grating lines
- H03H9/02732—Bilateral comb like grating lines
-
- 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
- H03H9/64—Filters using surface acoustic waves
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
Abstract
The present invention provides a surface acoustic wave device, including: a piezoelectric substrate having an upper surface and a lower surface disposed opposite to each other; an IDT electrode formed on an upper surface of the piezoelectric substrate for exciting a radio frequency signal applied to the IDT electrode into an elastic wave; wherein the IDT electrode includes: an IDT base electrode which is a comb electrode having a uniform thickness and is formed on the upper surface of the piezoelectric substrate; the IDT additional electrode is an electrode block arranged in an array, is formed on the electrode finger surface of the comb-teeth electrode of the IDT basic electrode, and is jointed with the IDT basic electrode so as to perform elastic wave conversion. The IDT electrode with one-dimensional design is optimized and improved, so that higher Q value and lower insertion loss are realized.
Description
Technical Field
The invention relates to the technical field of surface acoustic waves, in particular to a surface acoustic wave filter for communication technology.
Background
Currently, in a communication device such as a mobile phone, a filter device is used to separate a signal having a different frequency band such as a transmission signal from a reception signal. As more communication bands are used nationally or globally and the requirements on filter performance are continually "tightened", there is a constant effort to improve out-of-band filters and to provide steeper skirts. The dominant radio frequency filter technology today is Surface Acoustic Wave (SAW) technology, which offers superior performance due to its robustness, design flexibility, and low cost.
The mobile market continues to increase the demand for duplexers with low insertion loss filters of high selectivity and excellent isolation. Reducing filter loss translates directly into efficient use of bandwidth, higher bit rates, reliable communication, and extended battery life. These filters may use surface acoustic wave resonators that include one or more interdigital transducer (IDT) electrodes and reflectors, all of which are formed on a single crystal low loss piezoelectric substrate made of lithium niobate or lithium tantalate, quartz.
The main building element resonators of SAWs are interdigital transducers (IDTs), reflection gratings, and electrical bus bars. In recent years, SAW assemblies have improved performance, although the Q factor is still insufficient to achieve sufficiently low losses and steep skirts. Performance needs to be significantly improved to meet low insertion loss and higher Q values. Careful observation of the state-of-the-art technology suggests that the dominant losses in SAW filters are extrinsic, originating from the IDT design itself.
Disclosure of Invention
In order to solve the related problems in the prior art, the present invention provides a surface acoustic wave device, including: a piezoelectric substrate having an upper surface and a lower surface disposed opposite to each other; an IDT electrode formed on an upper surface of the piezoelectric substrate for exciting a radio frequency signal applied to the IDT electrode into an elastic wave; wherein the IDT electrode includes: an IDT base electrode which is a comb-tooth electrode having a uniform thickness and is formed on the upper surface of the piezoelectric substrate; the IDT additional electrode is an electrode block arranged in an array, is formed on the electrode finger surface of the comb-tooth electrode of the IDT basic electrode, and is jointed with the IDT basic electrode so as to perform elastic wave conversion.
Wherein a thickness of the IDT additional electrode is different from a thickness of the IDT base electrode.
Wherein an edge of the IDT additional electrode has an inclined surface which forms an angle in a range of 60 DEG to 90 DEG with a plane on which the piezoelectric substrate is located.
Wherein an edge of the IDT additional electrode has an inclined surface which forms an angle in a range of 90 DEG to 110 DEG with a plane on which the piezoelectric substrate is located.
Further, the width of the IDT additional electrode is different from the electrode finger width of the comb-teeth electrode at the joint.
Wherein the width of the electrode fingers of the IDT base electrode is constant along the length direction of the electrode fingers of the comb-shaped electrode, and the width of the IDT additional electrode varies along the length direction of the electrode fingers of the comb-shaped electrode.
Preferably, the width of the IDT additional electrode is smaller than the width of the electrode fingers of the IDT base electrode.
Further, the width of the additional electrode of the IDT is larger than that of the electrode fingers of the base electrode of the IDT.
Wherein, the electrode block of the IDT additional electrode has a projection pattern on the upper surface of the piezoelectric substrate which is approximately circular.
Wherein a projection pattern of the electrode block of the IDT additional electrode on the upper surface of the piezoelectric substrate is an irregular quadrangle.
Still further, the IDT additional electrode has a single-crystal metal structure.
Preferably, the material of the IDT additional electrode is one of chromium, tungsten, aluminum and gold.
Further, the IDT additional electrode has a single-layer structure.
Preferably, the IDT additional electrode has a multilayer structure.
Wherein a material of the IDT additional electrode is different from a material of the IDT base electrode.
The present invention also provides a method of manufacturing a surface acoustic wave device as set forth in claim 1, comprising: providing a piezoelectric substrate having an upper surface and a lower surface oppositely arranged; forming an IDT base electrode on an upper surface of the piezoelectric substrate, the IDT base electrode being a comb-tooth electrode having a uniform thickness; an IDT additional electrode is formed on an electrode finger surface of a comb-tooth electrode of the IDT base electrode, and is an electrode block arranged in an array, is joined to the IDT base electrode, and is used for exciting a radio-frequency signal applied to the IDT electrode into an elastic wave.
According to the surface acoustic wave device and the method of manufacturing the surface acoustic wave device of the present invention, the IDT electrode designed in one dimension is optimized and improved, thereby achieving a higher Q value and a lower insertion loss.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic longitudinal sectional view of a surface acoustic wave device according to the prior art.
Fig. 2 is a top view of an IDT electrode of a surface acoustic wave device according to the prior art.
Fig. 3 is a schematic longitudinal sectional view of a surface acoustic wave device according to a first embodiment of the present invention.
Fig. 4a is a top view of an IDT electrode of a surface acoustic wave device in which additional IDT electrodes are disposed in the finger regions of the IDT electrode according to a first embodiment of the present invention.
Fig. 4b is a top view of the IDT electrode of the surface acoustic wave device in which additional IDT electrodes are disposed in the finger regions, reflection regions and bus bar regions of the IDT electrode according to the first embodiment of the present invention.
Fig. 5 is a top view of an improved surface acoustic wave device IDT electrode according to yet another embodiment of the present invention.
Fig. 6 is a schematic longitudinal sectional view of a surface acoustic wave device according to a second embodiment of the present invention.
Fig. 7 is an enlarged schematic view of a single electrode finger of the IDT electrode of the surface acoustic wave device of the third embodiment.
Fig. 8 is a schematic longitudinal sectional view of a surface acoustic wave device according to a third embodiment of the present invention.
Fig. 9 is a schematic longitudinal sectional view of a surface acoustic wave device according to a fourth embodiment of the present invention.
Fig. 10 is a flowchart of a manufacturing process of a surface acoustic wave device according to a fifth embodiment of the present invention.
Reference numerals:
1. 10, 100-piezoelectric substrate
11-upper surface
12-lower surface
2. 20, 30, 40, 50-IDT electrode
21. 31, 41, 51-IDT base electrode
22. 32, 42, 52-IDT additional electrode
53-inclined plane
Detailed Description
So that the manner in which the above recited objects, features and advantages of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.
Example one
As shown in fig. 1 and 2, a surface acoustic wave device of the related art generally includes a piezoelectric substrate 1 having an upper surface 11 and a lower surface 12 disposed opposite to each other; an IDT electrode 2 formed on an upper surface of the piezoelectric substrate for exciting a radio frequency signal applied to the IDT electrode into an elastic wave.
The surface acoustic wave device provided by the present embodiment, as shown in fig. 3 and 4, includes: a piezoelectric substrate 10 having an upper surface and a lower surface which are oppositely disposed; an IDT electrode 20 formed on the upper surface of the piezoelectric substrate 10 for exciting a radio frequency signal applied to the IDT electrode 20 into an elastic wave; the piezoelectric substrate 10 may be a piezoelectric crystal such as quartz (SiO2), lithium niobate (LiNbO3), or lithium tantalate (LiTaO 3).
The IDT electrode 20 includes: an IDT base electrode 21 and an IDT additional electrode 22, wherein the IDT base electrode 21 is a comb-shaped electrode with uniform thickness and is formed on the upper surface of the piezoelectric substrate; the IDT additional electrode 22 is an electrode block arranged in an array, is formed on the electrode finger surface of the comb-shaped electrode of the IDT base electrode 21, and is joined to the IDT base electrode 21, thereby performing elastic wave conversion. The wavelength λ of the elastic wave is determined by the IDT base electrode 21, the thickness of the IDT base electrode 21 is between 100 and 500nm, the IDT base electrode may be a single-layer structure or a double-layer structure, and for example, the IDT base electrode may include a first metal layer and a second metal layer, where the first metal layer includes titanium metal and has a thickness of 10% to 50% of the thickness of the IDT base electrode 21, and the second metal layer includes aluminum metal and has a thickness of 50% to 90% of the thickness of the IDT base electrode 21. The IDT additional electrode 22 is in the form of an electrode block and may be designed to be circular or approximately quadrangular, for example, the projection pattern of the electrode block on the upper surface of the piezoelectric substrate 1 is approximately circular, or the projection pattern of the electrode block on the upper surface of the piezoelectric substrate 1 is approximately quadrangular in outline, and a quadrangle may be cut at an angle to form a polygon, which belongs to the design idea of the present invention. In the present invention, the IDT additional electrodes 22 are arranged in an array on the electrode finger surfaces of the comb-shaped electrodes of the IDT base electrode 21, and perform the conversion of the elastic wave together with the IDT base electrode 21, thereby ensuring a more complete band gap.
In this embodiment, the IDT additional electrodes 22 arranged in an array on the IDT base electrode 21 may be arranged uniformly in different patterns, for example, in a pattern of a sine curve, a diamond shape, a circle, etc., fig. 4 shows that the electrode blocks adjacent to the IDT additional electrodes 22 exhibit a layout pattern of a "m" shape, and fig. 5 shows that the electrode blocks of the IDT additional electrodes 22 exhibit a layout pattern of a diamond shape as a whole. The present invention is not limited thereto. The additional electrode of the IDT can be arranged in the finger area of the IDT electrode, can also be arranged in the reflection area, and further can be arranged in the bus bar area, so that the frequency characteristic can be improved. As shown in fig. 4(a), the IDT additional electrode is provided in the IDT electrode finger region, and fig. 4(b) and 5(b) show the IDT additional electrode is provided in the IDT electrode finger region, the reflection region, and the bus bar region, respectively.
In specific design, the IDT additional electrode 22 is made of a single-crystal metal structure, preferably made of one of chromium, tungsten, aluminum and gold, or made of another single-crystal metal structure, but preferably made of a material different from that of the IDT base electrode 21, so as to ensure better chemical stability and better electromigration resistance. In the structure of the IDT additional electrode 22, a single-layer structure or a multi-layer structure is possible, and further improved frequency characteristics can be realized.
Example two
Similarly to the embodiment, the surface acoustic wave device according to the present embodiment, as shown in fig. 6, includes: a piezoelectric substrate 100 having an upper surface and a lower surface disposed oppositely; the IDT electrode 30 is formed on the upper surface of the piezoelectric substrate 100 and is used to excite a radio frequency signal applied to the IDT electrode 30 into an elastic wave. The IDT electrode 30 comprises an IDT base electrode 31 and an IDT additional electrode 32, wherein the IDT base electrode 31 is a comb-tooth electrode with uniform thickness and is formed on the upper surface of the piezoelectric substrate; the IDT additional electrode 32 is an electrode block arranged in an array, is formed on the electrode finger surface of the comb-teeth electrode of the IDT base electrode 31 in a certain arrangement rule, and is joined to the IDT base electrode 31, thereby performing elastic wave conversion. The wavelength λ of the elastic wave is determined by the IDT base electrode 31, the thickness of the IDT base electrode 31 is between 100 nm and 500nm, and the structural design of the IDT base electrode 31 is similar to that of the embodiment and is not described herein again.
The IDT additional electrode 32 is in the form of an electrode block, and may be designed to be a circle, an irregular quadrilateral, or an approximate quadrilateral, for example, a projected pattern of the electrode block on the upper surface of the piezoelectric substrate 100 is an approximate circle, or a projected pattern of the electrode block on the upper surface of the piezoelectric substrate 100 is an approximate outline of a quadrilateral, and a polygon may be formed by performing corner cutting on the quadrilateral, which belongs to the design concept of the present invention. The IDT additional electrode 32 is arranged in an array on the electrode finger surface of the comb-tooth electrode of the IDT base electrode 31, and performs conversion of an elastic wave together with the IDT base electrode 31. In this embodiment, the shape of the IDT additional electrode 32 is further designed.
In terms of thickness, the thickness h2 of the IDT additional electrode 32 may be the same as or different from the thickness h1 of the IDT base electrode 31, and in this embodiment, the thickness is preferably different, and more preferably, the thickness of the IDT additional electrode 32 is larger than the thickness of the IDT base electrode 31, and further, the thickness h2 of the IDT additional electrode 32 is 1 to 5 times the thickness h1 of the IDT base electrode 31, and as shown in fig. 6, the thickness of the IDT additional electrode 32 is 1.5 times the thickness of the IDT base electrode 31, that is, h2 ≈ 1.5h 1. The dimensions of the electrodes in the figures are exaggerated to illustrate the design of the present invention.
EXAMPLE III
Other aspects of the IDT additional electrode, such as width, can also be designed for further performance optimization. For example, on the basis of the second embodiment, the present embodiment is designed to be further improved. The piezoelectric substrate and the IDT electrode are configured in a manner similar to that of example two, and will not be described here. In the present embodiment, the width of the IDT electrode 40 is designed, and as shown in fig. 7, an enlarged view of a single electrode finger of the IDT electrode is shown. The IDT electrode 40 comprises an IDT basic electrode 41 and an IDT additional electrode 42, wherein the IDT basic electrode 41 is a comb-tooth electrode with uniform thickness and is formed on the upper surface of the piezoelectric substrate; the IDT additional electrode 42 is an electrode block arranged in an array, is formed on the electrode finger surface of the comb-teeth electrode of the IDT base electrode 41 in a certain arrangement rule, and is joined to the IDT base electrode 41, thereby performing elastic wave conversion.
Taking the example that the adjacent electrode blocks of the IDT additional electrode 42 are arranged in a "m" shape, as shown in fig. 7, the width w of the electrode fingers of the IDT base electrode 41 is constant along the length direction of the electrode fingers of the comb-teeth electrode and is always w, and the width w of the IDT additional electrode 42 is varied along the length direction of the electrode fingers of the comb-teeth electrode, so that the IDT additional electrode 42 having different shapes, such as a circle, a substantially quadrangle, etc., can be provided on the surface of the IDT base electrode 41. Taking the example that the electrode block of the IDT additional electrode 42 in fig. 7 is oblong, the section a and the section B are cut, respectively, to obtain a section 8(a) at a and a section 8(B) at B. It can be seen that at a, width w1 of IDT additional electrode 42 is substantially equal to width w of the electrode fingers of IDT base electrode 41, and at B, IDT additional electrode 42 has width w2, which is smaller than width w of the electrode fingers of IDT base electrode 41. Therefore, in the design concept of the present invention, the width of the additional IDT electrode may be larger or smaller than the width of the electrode fingers of the basic IDT electrode, or may be the same as the width of the electrode fingers of the basic IDT electrode, so that the additional IDT electrode can be designed more flexibly.
The width 42 of the additional IDT electrode is the same as the electrode finger width of the comb-teeth electrode of the basic IDT electrode 41 at the joint, but it is also possible to design the width of the joint between the additional IDT electrode and the comb-teeth electrode to be different in actual design, and the design is flexible according to the product performance requirements of the implementation process.
Example four
For further performance optimization, other aspects of the IDT additional electrode, such as the tilt angle, can also be designed. For example, the present embodiment is further improved and designed on the basis of the third embodiment. The piezoelectric substrate and the IDT electrode are configured similarly to the third embodiment, and will not be described here. In the present embodiment, the IDT electrode 50 includes an IDT base electrode 51 and an IDT additional electrode 52, wherein the inclination angle of the IDT electrode 50 is designed, as shown in fig. 9, the edge of the IDT additional electrode 52 has an inclined surface 53, and the inclined surface forms an angle θ with the plane of the piezoelectric substrate, where θ may be an acute angle, an obtuse angle or a right angle, and for example, the angle is preferably in a range of 60 ° to 90 °, and may be designed to be an angle in a range of 90 ° to 110 °. An implementation with an angle theta of 80 deg. is shown in fig. 9(a), and an implementation with an angle theta of 100 deg. is shown in fig. 9 (b).
EXAMPLE five
This embodiment presents a method of manufacturing the aforementioned surface acoustic wave device, as shown in fig. 10, comprising providing a piezoelectric substrate having an upper surface and a lower surface (a1) disposed opposite to each other; forming an IDT base electrode on an upper surface of the piezoelectric substrate, the IDT base electrode being a comb-tooth electrode (a2) having a uniform thickness; an IDT additional electrode is formed on an electrode finger surface of a comb-tooth electrode of the IDT base electrode, the IDT additional electrode being an electrode block arranged in an array, joined (a3) to the IDT base electrode, for exciting a radio-frequency signal applied to the IDT electrode into an elastic wave. The IDT additional electrode may be formed by sputtering deposition or by etching. Followed by a subsequent encapsulation process (a 4).
The surface acoustic wave device prepared by the method optimizes and improves the IDT electrode with the conventional one-dimensional design, thereby realizing higher Q value and lower insertion loss.
In the present invention, the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more. The specific meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims (16)
1. A surface acoustic wave device comprising: a piezoelectric substrate having an upper surface and a lower surface disposed opposite to each other; an IDT electrode formed on an upper surface of the piezoelectric substrate for exciting a radio frequency signal applied to the IDT electrode into an elastic wave; wherein the IDT electrode includes:
an IDT base electrode which is a comb electrode having a uniform thickness and is formed on the upper surface of the piezoelectric substrate;
the IDT additional electrode is an electrode block arranged in an array, is formed on the electrode finger surface of the comb-tooth electrode of the IDT basic electrode and is jointed with the IDT basic electrode so as to perform elastic wave conversion.
2. A surface acoustic wave device as set forth in claim 1, wherein:
the thickness of the IDT additional electrode is different from the thickness of the IDT base electrode.
3. A surface acoustic wave device as set forth in claim 2,
the edge of the IDT additional electrode has an inclined surface which forms an angle in the range of 60 DEG to 90 DEG with the plane of the piezoelectric substrate.
4. A surface acoustic wave device as set forth in claim 2,
the edge of the IDT additional electrode has an inclined surface which forms an angle in the range of 90 DEG to 110 DEG with the plane of the piezoelectric substrate.
5. A surface acoustic wave device as set forth in claim 1,
the width of the IDT additional electrode is different from the electrode finger width of the comb-teeth electrode at the joint.
6. A surface acoustic wave device as set forth in claim 5,
the width of the electrode fingers of the IDT base electrode is constant along the length direction of the electrode fingers of the comb-shaped electrode, and the width of the IDT additional electrode varies along the length direction of the electrode fingers of the comb-shaped electrode.
7. A surface acoustic wave device as set forth in claim 6,
the width of the IDT additional electrode is smaller than that of the electrode fingers of the IDT basic electrode.
8. A surface acoustic wave device as set forth in claim 6,
the width of the IDT additional electrode is larger than that of the electrode fingers of the IDT basic electrode.
9. A surface acoustic wave device as set forth in claim 6,
the electrode block of the IDT additional electrode has a projection pattern on the upper surface of the piezoelectric substrate in an approximately circular shape.
10. A surface acoustic wave device as set forth in claim 6,
the electrode block of the IDT additional electrode has a projection pattern on the upper surface of the piezoelectric substrate, which is substantially quadrangular.
11. A surface acoustic wave device as set forth in claim 1,
the IDT additional electrode is of a single-crystal metal structure.
12. A surface acoustic wave device as set forth in claim 11,
the IDT additional electrode is made of one of chromium, tungsten, aluminum and gold.
13. A surface acoustic wave device as set forth in claim 11,
the IDT additional electrode is of a single-layer structure.
14. A surface acoustic wave device as set forth in claim 11,
the IDT additional electrode is of a multilayer structure.
15. A surface acoustic wave device as set forth in claim 11,
the material of the IDT additional electrode is different from that of the IDT base electrode.
16. A method of manufacturing a surface acoustic wave device as set forth in claim 1, comprising:
providing a piezoelectric substrate having an upper surface and a lower surface oppositely arranged;
forming an IDT base electrode on an upper surface of the piezoelectric substrate, the IDT base electrode being a comb-tooth electrode having a uniform thickness;
an IDT additional electrode is formed on an electrode finger surface of a comb-tooth electrode of the IDT base electrode, and is an electrode block arranged in an array, is joined to the IDT base electrode, and is used for exciting a radio-frequency signal applied to the IDT electrode into an elastic wave.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210089875.8A CN114499442A (en) | 2022-01-25 | 2022-01-25 | Impedance matching device for surface acoustic wave device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210089875.8A CN114499442A (en) | 2022-01-25 | 2022-01-25 | Impedance matching device for surface acoustic wave device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114499442A true CN114499442A (en) | 2022-05-13 |
Family
ID=81474890
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210089875.8A Pending CN114499442A (en) | 2022-01-25 | 2022-01-25 | Impedance matching device for surface acoustic wave device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114499442A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011135618A (en) * | 2011-03-24 | 2011-07-07 | Taiyo Yuden Co Ltd | Piezoelectric thin-film resonator and manufacturing method therefor |
| CN102893521A (en) * | 2010-05-19 | 2013-01-23 | 株式会社村田制作所 | Surface acoustic wave device |
| CN105680820A (en) * | 2010-01-25 | 2016-06-15 | 埃普科斯股份有限公司 | Electro-acoustic transducer and manufacturing method thereof |
| CN109937534A (en) * | 2016-11-09 | 2019-06-25 | 株式会社村田制作所 | Acoustic wave device, high-frequency front-end circuit and communication device |
| CN110073596A (en) * | 2016-12-20 | 2019-07-30 | 株式会社村田制作所 | Acoustic wave device, high-frequency front-end circuit and communication device |
| CN113114159A (en) * | 2021-05-27 | 2021-07-13 | 北京超材信息科技有限公司 | Surface acoustic wave device |
-
2022
- 2022-01-25 CN CN202210089875.8A patent/CN114499442A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105680820A (en) * | 2010-01-25 | 2016-06-15 | 埃普科斯股份有限公司 | Electro-acoustic transducer and manufacturing method thereof |
| CN102893521A (en) * | 2010-05-19 | 2013-01-23 | 株式会社村田制作所 | Surface acoustic wave device |
| JP2011135618A (en) * | 2011-03-24 | 2011-07-07 | Taiyo Yuden Co Ltd | Piezoelectric thin-film resonator and manufacturing method therefor |
| CN109937534A (en) * | 2016-11-09 | 2019-06-25 | 株式会社村田制作所 | Acoustic wave device, high-frequency front-end circuit and communication device |
| CN110073596A (en) * | 2016-12-20 | 2019-07-30 | 株式会社村田制作所 | Acoustic wave device, high-frequency front-end circuit and communication device |
| CN113114159A (en) * | 2021-05-27 | 2021-07-13 | 北京超材信息科技有限公司 | Surface acoustic wave device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11824518B2 (en) | Acoustic wave device | |
| US9035725B2 (en) | Acoustic wave device | |
| EP1152529B1 (en) | Longitudinally coupled resonator-type surface acoustic wave filter | |
| EP2068444B1 (en) | Acoustic wave filter | |
| US11336259B2 (en) | Acoustic wave device, filter, and multiplexer | |
| US20220029601A1 (en) | Acoustic wave device | |
| CN110800212B (en) | Elastic wave device and composite filter device | |
| US20210152153A1 (en) | Acoustic wave element, acoustic wave filter, multiplexer, and communication apparatus | |
| CN108696266B (en) | Acoustic wave resonator, filter, and multiplexer | |
| JP2013138333A (en) | Elastic wave element | |
| US20210242857A1 (en) | Acoustic wave filter | |
| CN114270707A (en) | Elastic wave device | |
| CN110572138A (en) | Filtering device and manufacturing method thereof | |
| CN113632377B (en) | Longitudinally coupled resonator type elastic wave filter and filter device | |
| US11996828B2 (en) | Filter device | |
| US20220239280A1 (en) | Acoustic wave filter | |
| KR20030051385A (en) | Surface acoustic element and duplexer therewith | |
| CN116346081A (en) | Surface acoustic wave filter and filter element | |
| CN114499442A (en) | Impedance matching device for surface acoustic wave device | |
| KR19980019102A (en) | Surface acoustic wave resonator filter | |
| JP2002064358A (en) | Compound surface acoustic wave filter | |
| JP2022171054A (en) | Acoustic wave resonator, filter, and multiplexer | |
| US20240223157A1 (en) | Acoustic wave filter device and multiplexer | |
| WO2024116813A1 (en) | Elastic wave device and filter device | |
| WO2024135259A1 (en) | Elastic wave device and filter device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |