CN213460044U - High Q value aluminium nitride lamb wave resonator - Google Patents
High Q value aluminium nitride lamb wave resonator Download PDFInfo
- Publication number
- CN213460044U CN213460044U CN202022703114.6U CN202022703114U CN213460044U CN 213460044 U CN213460044 U CN 213460044U CN 202022703114 U CN202022703114 U CN 202022703114U CN 213460044 U CN213460044 U CN 213460044U
- Authority
- CN
- China
- Prior art keywords
- electrode
- aluminum nitride
- lamb wave
- wave resonator
- value
- 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.)
- Active
Links
Images
Landscapes
- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
Abstract
The utility model provides a high Q value aluminium nitride lamb wave syntonizer, include: an electrode, a membrane (2); the electrode includes: an interdigital electrode (1) and a bottom electrode (3); one end of the interdigital electrode (1) is connected with an RF signal; the other end of the interdigital electrode (1) is connected with the ground; the bottom electrode (3) is in electrical floating connection; the film (2) is arranged between the interdigital electrode (1) and the bottom electrode (3). The utility model discloses an adopt piezoelectric film, solved other conventional piezoelectric film hardly with semiconductor technology compatibility, dielectric constant too high, mechanical quality factor low scheduling problem. This makes the resonator that this patent proposed can play more excellent performance in high sensitivity smart sensor's application.
Description
Technical Field
The utility model relates to a syntonizer technical field specifically, relates to a high Q value aluminium nitride lamb wave syntonizer.
Background
With the rapid development of sensor technology, the Q value of the existing resonator is difficult to meet the design requirement of a high-precision sensor.
Patent document CN111404509A discloses a high-Q resonant device, which ensures the high-Q of the resonator and the consistency of the electrical parameters of the device by additionally inserting an etching stop layer.
The defects of the prior art are as follows: the conventional piezoelectric film may have the problems of low mechanical quality factor, poor compatibility of a semiconductor process and the like, and the aluminum nitride film or scandium-doped aluminum nitride adopted by the invention can be perfectly compatible with the semiconductor process and has stronger mechanical stability, so that the aluminum nitride resonator provided by the invention has wide applicability; most of aluminum nitride acoustic wave resonators improve the Q value of the resonators in a limited way by reducing mechanical wave leakage, and the method for reducing the electromechanical coupling coefficient K2 by introducing the 'half-finger' electrode, which is proposed by the patent, breaks the bottleneck of the conventional method, greatly improves the Q value and achieves the highest Q value in the field of aluminum nitride resonators.
SUMMERY OF THE UTILITY MODEL
To overcome the drawbacks of the prior art, the present invention provides a high Q-value aluminum nitride lamb wave resonator.
According to the utility model provides a pair of high Q value aluminium nitride lamb wave syntonizer, a serial communication port, include: an electrode, a membrane 2; the electrode includes: interdigital electrode 1, bottom electrode 3; one end of the interdigital electrode 1 is connected with an RF signal; the other end of the interdigital electrode 1 is connected with the ground; the bottom electrode 3 adopts electric floating connection; the film 2 is arranged between the interdigital electrode 1 and the bottom electrode 3.
Preferably, the material of the electrode can adopt any one of the following materials: -platinum; -aluminium; -molybdenum; -gold; -silver; -ruthenium.
Preferably, the material of the film can adopt any one of the following materials: -aluminum nitride; scandium-doped aluminum nitride.
Preferably, when an electric field is applied between the interdigital electrode 1 and the bottom electrode 3, mechanical vibration can be generated in the thin film, thereby forming lamb wave resonance in the horizontal direction, i.e., S0 resonance mode.
Preferably, 6 interdigital electrodes 1 are used; the high-Q-value aluminum nitride lamb wave resonator can excite a 6-order S0 resonance mode.
Preferably, the resonance frequency of the S0 resonance mode can be adjusted by the width of the interdigital electrode 1 and the electrode spacing;
the Q value of the aluminum nitride lamb wave resonator can be improved by reducing the electromechanical coupling coefficient K2 of the aluminum nitride lamb wave resonator.
When the structure of the resonator is determined, the figure of merit of the resonator is determined, namely the product of the electromechanical coupling coefficient K2 and the Q value of the high-Q-value aluminum nitride lamb wave resonator. Therefore, the electromechanical coupling coefficient K2 and the Q value are in a negative correlation relationship, which means that the Q value of the resonator can be increased by decreasing the electromechanical coupling coefficient K2.
Preferably, the method further comprises the following steps: a half-finger electrode 4;
a half-finger electrode 4 with the same length as the original electrode but only half width is respectively introduced at two sides of the 6 interdigital electrodes 1;
preferably, one end of the semi-finger electrode 4 is connected with an RF signal; the other end of the semi-finger electrode 4 is connected with the ground; the high-Q-value aluminum nitride lamb wave resonator can excite overtone resonance of an S0 resonance mode; namely 6 th, 8 th, 10 th and 12 th order S0 resonant modes.
Preferably, the high-Q-value aluminum nitride lamb wave resonator can excite any one of the following S0 resonant modes: -6 th order S0 resonant mode; -8 th order S0 resonant mode; -10 th order S0 resonant mode; -12 th order S0 resonant mode; the 8 th order S0 resonant mode is a main mode in harmonic overtone resonance of the S0 resonant mode; plays a dominant role in all resonant modes. The electromechanical coupling coefficient K2 of the resonator is effectively reduced by the several 'overtone' resonances excited in the above way, and the electromechanical coupling coefficients K2 corresponding to all 'overtone' resonant modes are smaller than the S0 resonant mode in the original 1, so that the Q value of the original resonator is greatly improved at each resonant frequency. The electromechanical coupling coefficient K2 of the conventional aluminum nitride resonator shown in fig. 1 is about 1.4%, and the Q value is 1750, whereas the electromechanical coupling coefficient K2 of the resonator proposed in the present patent can be reduced to 0.86%, and the corresponding Q value is more than 5500, which is the highest Q value that can be achieved in the aluminum nitride resonator field to date according to the knowledge of the authors. It should be noted that the number of the interdigital electrodes of the resonator proposed in this patent may also be two or four, and when the number of the interdigital electrodes is smaller, the influence of the later introduced "half-finger" electrode on the resonator performance is larger, and the Q value of the resonator is also higher. In addition, the width of the electrode of the 'half finger' can also be adjusted to a certain degree to optimize the resonance mode of the resonator and enhance the performance of the resonator.
Preferably, a high-Q aluminum nitride lamb wave resonator is used, comprising: step S1: preparing and cleaning a monocrystalline silicon wafer; step S2: evaporating a bottom electrode on a silicon substrate; step S3: sputtering an aluminum nitride film layer; step S4: coating, exposing and etching the shape of the interdigital electrode by adopting photoresist; step S5: sputtering a metal layer and stripping the interdigital electrode; step S6: preparing a silicon dioxide mask by utilizing a Plasma Enhanced Chemical Vapor Deposition (PECVD) technology; step S7: etching the aluminum nitride film layer by utilizing a reactive ion etching ICP-RIE technology; step S8: removing the silicon dioxide mask; step S9: the oscillating stack was released using xenon difluoride XeF 2.
Compared with the prior art, the utility model discloses following beneficial effect has:
1. by adopting the piezoelectric film, the problems that other conventional piezoelectric films are difficult to be compatible with a semiconductor process, the dielectric constant is overhigh, the mechanical quality factor is low and the like are solved. This makes the resonator that this patent proposed can play more excellent performance in high sensitivity smart sensor's application.
2. The utility model discloses an adopt "half to indicate" electrode, solved the problem that conventional aluminium nitride syntonizer hardly improves the Q value.
3. The utility model discloses a "partly indicate" the overtone "resonance that" the electrode introduced with effectual reduction syntonizer electromechanical coupling coefficient K2 to the Q value of very big improvement syntonizer breaks the bottleneck of conventional aluminium nitride syntonizer Q value, reaches the highest Q value in aluminium nitride syntonizer field.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
fig. 1 is a schematic structural diagram of a first conventional resonator based on an aluminum nitride piezoelectric thin film in an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a second conventional resonator based on an aluminum nitride piezoelectric thin film according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a first high-Q value lamb wave resonator in an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of a second high-Q value lamb wave resonator in an embodiment of the present invention.
Fig. 5 is a schematic flow chart of a method for manufacturing a high-Q lamb wave resonator by using a standard photolithography technique according to an embodiment of the present invention.
In the figure:
1-interdigital electrode 5-silicon
2-thin film 6-photoresist
3-bottom electrode 7-silicon dioxide
4-half finger electrode
Detailed Description
The present invention will be described in detail with reference to the following embodiments. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that various changes and modifications can be made by one skilled in the art without departing from the spirit of the invention. These all belong to the protection scope of the present invention.
Fig. 1 and 2 show a conventional resonator based on an aluminum nitride (AlN) piezoelectric film, which is mainly composed of interdigital electrodes 1, a film 2, and a bottom electrode 3. The interdigital electrodes in the figure are respectively connected with the RF signal and the ground in a replacing way, the bottom electrode is electrically floating, and the electrode material can be platinum (Pt), aluminum (Al), molybdenum (Mo), gold (Au), silver (Ag), ruthenium (Ru) and the like. The material of the thin film can be aluminum nitride (AlN) and scandium-doped aluminum nitride (AlScN). When an electric field is applied between the interdigital electrode and the bottom electrode, mechanical vibration is generated in the thin film to form lamb wave resonance in the horizontal direction, i.e., S0 resonance mode. The resonator shown in fig. 1 with 6 interdigital electrodes can excite a 6 th order S0 resonance mode, and the resonance frequency of the resonance mode can be adjusted by the interdigital electrode width and the electrode spacing. When the structure of the resonator is determined, the figure of merit is determined accordingly, namely the product of the electromechanical coupling coefficient K2 and the Q value. Therefore, the electromechanical coupling coefficient K2 and the Q value are in a negative correlation relationship, which means that the Q value of the resonator can be increased by decreasing the electromechanical coupling coefficient K2.
Based on this, this patent proposes a high-Q lamb wave resonator as shown in fig. 3 and 4. It introduces a "half finger" electrode 4 with the same length but half width as the original electrode at both sides of the 6 interdigital electrodes 1 shown in fig. 1, and the two electrodes are connected with RF signal and ground respectively. By introducing these two "half-finger" electrodes, the original acoustic wave boundaries and electric field of the resonator of fig. 1 are altered to such an extent that the "overtone" resonance of the S0 mode, i.e., the 6 th, 8 th, 10 th and 12 th order S0 modes, is excited. The 8 th order resonant mode is the main mode of the excited harmonic resonance, and plays a dominant role in all resonant modes. The electromechanical coupling coefficient K2 of the resonator is effectively reduced by the several 'overtone' resonances excited in the above way, and the electromechanical coupling coefficients K2 corresponding to all 'overtone' resonant modes are smaller than the S0 resonant mode in the original 1, so that the Q value of the original resonator is greatly improved at each resonant frequency. The electromechanical coupling coefficient K2 of the conventional aluminum nitride resonator shown in fig. 1 is about 1.4%, and the Q value is 1750, whereas the electromechanical coupling coefficient K2 of the resonator proposed in the present patent can be reduced to 0.86%, and the corresponding Q value is more than 5500, which is the highest Q value that can be achieved in the aluminum nitride resonator field to date according to the knowledge of the authors. It should be noted that the number of the interdigital electrodes of the resonator proposed in this patent may also be two or four, and when the number of the interdigital electrodes is smaller, the influence of the later introduced "half-finger" electrode on the resonator performance is larger, and the Q value of the resonator is also higher. In addition, the width of the electrode of the 'half finger' can also be adjusted to a certain degree to optimize the resonance mode of the resonator and enhance the performance of the resonator.
The high-Q lamb wave resonator proposed by the patent can be prepared by standard photoetching technology. As shown in fig. 5, the process flow of the resonator is as follows: 1. cleaning a monocrystalline silicon wafer; 2. evaporating a bottom electrode on a silicon substrate; 3. sputtering an aluminum nitride film layer; 4. coating photoresist, exposing and etching to form the shape of the interdigital electrode; 5. sputtering a metal layer and stripping the interdigital electrode; 6. preparing a silicon dioxide mask by utilizing a Plasma Enhanced Chemical Vapor Deposition (PECVD) technology; 7. etching the aluminum nitride film layer by utilizing a reactive ion etching (ICP-RIE) technology; 8. removing the silicon dioxide mask; 9. xenon difluoride (XeF2) was used to release the oscillating stack.
In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.
The foregoing description of the specific embodiments of the invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.
Claims (8)
1. A high-Q aluminum nitride lamb wave resonator, comprising: an electrode, a membrane (2);
the electrode includes: an interdigital electrode (1) and a bottom electrode (3);
one end of the interdigital electrode (1) is connected with an RF signal;
the other end of the interdigital electrode (1) is connected with the ground;
the bottom electrode (3) is in electrical floating connection;
the film (2) is arranged between the interdigital electrode (1) and the bottom electrode (3).
2. The high-Q aluminum nitride lamb wave resonator according to claim 1, wherein the electrode is made of any one of the following materials:
-platinum;
-aluminium;
-molybdenum;
-gold;
-silver;
-ruthenium;
the film (2) can adopt any one of the following materials:
-aluminum nitride;
scandium-doped aluminum nitride.
3. The high-Q-value aluminum nitride lamb wave resonator according to claim 1, characterized in that when an electric field is applied between the interdigital electrode (1) and the bottom electrode (3), mechanical vibration can be generated in the thin film (2), thereby forming lamb wave resonance in the horizontal direction.
4. The high-Q aluminium nitride lamb wave resonator according to claim 1, characterized in that 6 interdigital electrodes (1) are used;
the high-Q-value aluminum nitride lamb wave resonator can excite a 6-order S0 resonance mode.
5. The high-Q-value aluminum nitride lamb wave resonator according to claim 4, characterized in that the resonance frequency of the S0 resonance mode can be adjusted by the width of the interdigital electrode (1) and the electrode spacing;
the Q value of the aluminum nitride lamb wave resonator can be improved by reducing the electromechanical coupling coefficient K2 of the aluminum nitride lamb wave resonator.
6. The high-Q aluminum nitride lamb wave resonator according to claim 4, further comprising: a half-finger electrode (4);
half finger electrodes (4) with the same length but only half width as the original electrodes are respectively introduced at two sides of the 6 finger electrodes (1).
7. The high-Q aluminum nitride lamb wave resonator according to claim 6, wherein one end of the half-finger electrode (4) is connected with an RF signal;
the other end of the semi-finger electrode (4) is connected with the ground;
the high-Q-value aluminum nitride lamb wave resonator can excite overtone resonance of an S0 resonance mode.
8. The high-Q aluminum nitride lamb wave resonator according to claim 5, wherein the high-Q aluminum nitride lamb wave resonator can excite any one of the following S0 resonant modes:
-6 th order S0 resonant mode;
-8 th order S0 resonant mode;
-10 th order S0 resonant mode;
-12 th order S0 resonant mode;
the 8 th order S0 resonant mode is the primary mode in the harmonic overtone resonance of the S0 resonant mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022703114.6U CN213460044U (en) | 2020-11-20 | 2020-11-20 | High Q value aluminium nitride lamb wave resonator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022703114.6U CN213460044U (en) | 2020-11-20 | 2020-11-20 | High Q value aluminium nitride lamb wave resonator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213460044U true CN213460044U (en) | 2021-06-15 |
Family
ID=76303505
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022703114.6U Active CN213460044U (en) | 2020-11-20 | 2020-11-20 | High Q value aluminium nitride lamb wave resonator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213460044U (en) |
-
2020
- 2020-11-20 CN CN202022703114.6U patent/CN213460044U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN210431367U (en) | Transverse field excitation film bulk acoustic resonator with adjustable frequency | |
| US10263598B2 (en) | Acoustic resonator and method of manufacturing the same | |
| EP1196990B1 (en) | Resonator structure and a filter comprising such a resonator structure | |
| CN103684336B (en) | Resonator device with electrode comprising embedded type temperature compensation layer | |
| KR20110058704A (en) | Hybrid bulk acoustic wave resonator | |
| JP2003017964A (en) | Manufacturing method for acoustic wave element | |
| JP2003289236A (en) | Quartz oscillator and manufacturing method therefor | |
| CN111431501A (en) | Lamb wave resonator and preparation method thereof | |
| CN107026627A (en) | Orthogonal array nano-pillar FBAR and preparation method thereof and wave filter | |
| US20050168105A1 (en) | Electronic component, manufacturing method for the same, and filter, duplexer, and electronic communication apparatus using the same | |
| JPH01157108A (en) | Piezoelectric thin film resonator | |
| CN108988812A (en) | Acoustic resonator and method for manufacturing acoustic resonator | |
| CN112350679A (en) | Bulk acoustic wave resonator based on silicon piezoelectric film structure and preparation method thereof | |
| EP4318945A1 (en) | Baw filter structure and preparation method | |
| WO2004088840A1 (en) | Piezoelectric thin film device and method of producing the same | |
| WO2022000809A1 (en) | Resonator and method for making same | |
| CN213460044U (en) | High Q value aluminium nitride lamb wave resonator | |
| JP2002374146A (en) | Piezoelectric vibrating reed and piezoelectric device | |
| CN112332794A (en) | High-power-capacity bulk acoustic wave resonator with reflection layer, and preparation method and system thereof | |
| JP2002076824A (en) | Piezoelectric thin film resonator, filter and electronic device | |
| CN112421200A (en) | Aluminum nitride lamb wave resonator with extremely high Q value and processing method | |
| JPH11340775A (en) | Piezoelectric oscillator | |
| JPS6382116A (en) | Piezoelectric thin film resonator and its manufacture | |
| CN114614793A (en) | Film bulk acoustic resonator with temperature compensation structure and preparation method thereof | |
| CN116488608A (en) | Film bulk acoustic resonator, manufacturing method thereof and filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220209 Address after: 325038 Wenzhou, Zhejiang Province, Zhejiang science and technology city innovation and entrepreneurship new phase 1 building 506 room (self declaration) Patentee after: Zhejiang Xingyao Semiconductor Co.,Ltd. Address before: 325024 Zhejiang Wenzhou Longwan District Yong Zhong street Wenzhou South Zhejiang science and technology city innovation and business new world 1 building 505 (for office use only) Patentee before: Zhejiang Xintang Zhixin Technology Co.,Ltd. |