CN207475507U - RF MEMS filters - Google Patents
RF MEMS filters Download PDFInfo
- Publication number
- CN207475507U CN207475507U CN201820031280.6U CN201820031280U CN207475507U CN 207475507 U CN207475507 U CN 207475507U CN 201820031280 U CN201820031280 U CN 201820031280U CN 207475507 U CN207475507 U CN 207475507U
- Authority
- CN
- China
- Prior art keywords
- layer
- piezoelectric
- metal electrode
- piezoelectric layer
- mems filters
- 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
Abstract
The utility model proposes a kind of RF MEMS filters, including：Silicon substrate or piezoelectric substrate；The piezoelectric membrane of deposition on the silicon substrate；The metal electrode being deposited on piezoelectric substrate or piezoelectric membrane；The insulating layer being filled between metal electrode and the piezoelectric layer being deposited on metal electrode and insulating layer realize that surface acoustic wave (SAW) filters with this；The temperature compensating layer being deposited on above-mentioned piezoelectric layer.The utility model has used double piezoelectric layers, can pass through the collocation of piezoelectricity layer material and film crystal orientation and thickness control, the mechanical-electric coupling performance of adjusting means；Simultaneously compared to traditional single-piezoelectric layer SAW, the linewidth requirements to photoetching can be effectively reduced during identical frequency device is obtained.
Description
Technical field
The utility model is related to a kind of wireless communication RF front-end devices, particularly a kind of RF MEMS filters.
Background technology
With the development of wireless communication applications, requirement of the people for data transmission bauds is higher and higher.In mobile communication
Field, the first generation are analogue techniques, and the second generation realizes digitized voice communications, and the third generation (3G) is using multimedia communication as spy
Sign, traffic rate is increased to 1Gbps by forth generation (4G), time delay is reduced to 10ms, and the 5th generation (5G) was a new generation after 4G
Mobile communication technology, although the technical specification of 5G is completely clear and definite not yet with standard, compared with 3G, 4G, network transmission speed
Rate and network capacity will be substantially improved.If what is mainly solved from 1G to 4G is interpersonal communication, 5G will solve people
With people and object except people, the communication between object and object, i.e. all things on earth interconnects, and realizes the hope of " information follow one's inclinations to, all things on earth tentacle and "
Scape.
It is the high usage of frequency spectrum resource and the complication of communications protocol to rise corresponding with data transfer rate.Due to frequency spectrum
It is limited, in order to meet the needs of data transfer rate, it is necessary to make full use of frequency spectrum；Simultaneously in order to meet the needs of data transfer rate, since 4G
Also use carrier aggregation technology so that an equipment can utilize different carrier spectrum transmission data simultaneously.On the other hand,
In order to support enough data transmission rates in limited bandwidth, communication protocol becomes to become increasingly complex, therefore to radio frequency system
Various performances also proposed stringent demand.
In RF front-end module, radio-frequency filter plays a crucial role.It can be by out-of-band interference and noise
Filter out meet the needs of radio frequency system and communications protocol are for signal-to-noise ratio.As communication protocol becomes increasingly complex, in frequency band
Outer requirement is also higher and higher so that the design of wave filter increasingly has challenge.In addition, the frequency band number supported with mobile phone needs
Mesh constantly rises, and the wave filter used quantity is needed also constantly to rise in every Mobile phone.
Radio-frequency filter most mainstream is achieved in that SAW filter and based on thin film bulk acoustic wave resonator at present
The wave filter of technology.Thin film bulk acoustic wave resonator is mainly used for high frequency (such as frequency range more than 2.5GHz), and manufacturing process compares
Complexity, cost are higher.And SAW filter is mainly used for middle low frequency (the such as less than frequency range of 2.5GHz), manufacturing process phase
To fairly simple, cost is much lower compared to thin film bulk acoustic wave resonator, is easier to be received by market.
In traditional structure and preparation method, mainly metal interdigital structure is prepared on piezoelectric substrate, such as quartz, niobium
The piezoelectric substrates such as sour lithium, barium titanate.But the material property of aforesaid substrate is limited to, in order to obtain higher frequency, it is desirable that line
It is wide less and less, the difficulty of photoetching process is considerably increased, reduces the yield of finished product, and affects the application range of SAW.
Utility model content
In order to reduce to the high request of photoetching process in prior art technology, while adjust the mechanical-electric coupling of SAW device
Can, the utility model devises the RF MEMS filters with double piezoelectric layers.
Specifically, the technical solution of the utility model is as follows：
A kind of RF MEMS filters, which is characterized in that including：
First piezoelectric layer；
The metal electrode being deposited on first piezoelectric layer；
The dielectric layer being filled between the metal electrode；And
The second piezoelectric layer being deposited on the metal electrode and the dielectric layer.
Preferably, the temperature compensating layer on second piezoelectric layer is further included.
Preferably, the material of the metal electrode for tungsten, silver, zirconium, molybdenum, platinum platinum, ruthenium, iridium, titanium tungsten, copper, titanium, chromium, hafnium,
One of aluminium or combination.
Preferably, be filled in dielectric layer material between the metal electrode include silica, silicon nitride or other
Insulating materials.
Preferably, the temperature compensating layer is silica membrane.
Preferably, first piezoelectric layer is identical with the material of second piezoelectric layer.
Preferably, the material of first piezoelectric layer and second piezoelectric layer differs.
Preferably, the material of first piezoelectric layer for lithium niobate, lithium tantalate, aluminium nitride, lead zirconate titanate, zinc oxide it
One.
Preferably, the material of second piezoelectric layer for lithium niobate, lithium tantalate, aluminium nitride, lead zirconate titanate, zinc oxide it
One.
Preferably, the metal electrode is interdigital structure.
The advantageous effects of the utility model are:The mechanical-electric coupling ability of SAW device is adjusted using double piezoelectric layer structures,
And the technology difficulty of photoetching is reduced, the frequency of device is improved under identical photoetching process ability condition.
Description of the drawings
Fig. 1 is the structure diagram of the silicon substrate structure RF MEMS filters of the utility model embodiment；
Fig. 2 is the structure diagram of the piezoelectric substrate structure RF MEMS filters of the utility model embodiment；
Fig. 3 is the performance pair of lower pair of piezoelectric layer SAW resonator of same process parameter and size condition and traditional SAW resonator
Than figure, wherein, left-most curve is the single-piezoelectric layer SAW resonator mechanical admittance curves using lithium niobate as piezoelectric substrate in Fig. 3, right
Side curve be using lithium niobate substrate as the first piezoelectric layer, LiNbO_3 film as the second piezoelectric layer double piezoelectric layer SAW resonance
Device mechanical admittance curves, the positive resonant frequency and electromechanical coupling factor of the two be respectively 1882MHz, 4.62% and 2270MHz,
5.39%；
Fig. 4 is the preparation process flow diagram of silicon substrate structure RF MEMS filters that the utility model is proposed；
Fig. 5 is the preparation process flow diagram of piezoelectric substrate structure RF MEMS filters that the utility model is proposed.
Specific embodiment
The utility model is described further in the following with reference to the drawings and specific embodiments.
Embodiment 1
The utility model proposes a kind of novel RF MEMS filters, and concrete structure is referring to shown in Fig. 1,2.It includes：
First piezoelectric layer；The metal electrode being deposited on first piezoelectric layer；The dielectric layer being filled between the metal electrode；With
And it is deposited on the second piezoelectric layer on the metal electrode and the dielectric layer.
Wherein, the first piezoelectric layer is the piezoelectric membrane 200 being deposited on silicon substrate 100 or directly uses piezoelectric substrate
101；The metal electrode 300 being deposited on piezoelectric substrate 100 or above-mentioned piezoelectric membrane 200；The metal electrode is for example etched
Into interdigital structure, the dielectric layer 400 being filled between above-mentioned metal electrode 300 is deposited on above-mentioned metal electrode and dielectric layer
The second piezoelectric layer thin film 500, further include the temperature compensating layer 600 being deposited on the second piezoelectric layer thin film.The utility model
In RF MEMS be radio frequency micro-mechanic system, SAW is SAW resonator and its derivative device.
In the utility model, the mechanical-electric coupling ability of SAW device is adjusted using the collocation of two layers of piezoelectricity layer material, from
And the frequency of device is improved under the conditions of identical lithographic line width, reduce the technology difficulty of photoetching.As shown in figure 3, the utility model
For using lithium niobate as piezoelectric layer material, the mechanical admittance curves of lithium niobate single-piezoelectric layer and double piezoelectric layer SAW resonators are compared,
By comparison result it can be seen that：The positive resonant frequency and electromechanical coupling factor of double piezoelectric layers are above the positive resonance frequency of single-piezoelectric layer
Rate and electromechanical coupling factor are respectively 2270MHz, 5.39% and 1882MHz, 4.62%.
Further, the utility model does not do stringent restriction to the material of two layers of piezoelectric material, can be common
It is selected and is arranged in pairs or groups in piezoelectric material, as long as being conducive to improve the mechanical-electric coupling ability and device frequency of SAW device.
The RF MEMS filters of the utility model embodiment 1 can be manufactured by following processing step：
Deposit certain thickness piezoelectric membrane 200 in ready 100 upper surface of silicon chip, i.e. the first piezoelectric layer, wherein, the
One piezoelectric layer is, for example, one or a combination set of lithium niobate, lithium tantalate, aluminium nitride, lead zirconate titanate, zinc oxide, as shown in Fig. 4 (a).
The deposit metal electrodes layer 300 and graphical on piezoelectric membrane 200, graphically can be used dry etching or stripping
Separating process, as shown in Fig. 4 (b).
Deposition medium filled layer 400, such as carbon dioxide silicon, silicon nitride, until metal electrode layer 300 is completely covered, such as
Shown in Fig. 4 (c).
Dielectric layer is polished by chemical mechanical grinding (CMP) technique, makes dielectric layer that there is identical height with metal electrode
Degree, as shown in Fig. 4 (d).
Then it is simultaneously graphical that the second piezoelectric layer thin film 500 is deposited on the surface, wherein, the second piezoelectric layer is, for example, niobium
One or a combination set of sour lithium, lithium tantalate, aluminium nitride, lead zirconate titanate, zinc oxide, as shown in Fig. 4 (e).
Deposition temperature compensation layer 600 is lithographically formed required figure, and wherein temperature compensating layer is, for example, silica or it is mixed
Miscellaneous film, as shown in Fig. 4 (f).
For the mode of the direct RF MEMS filters that piezoelectric substrate is selected to make the utility model, specifically prepared
Journey does not need in addition select substrate, redeposited first pressure referring to Fig. 5 (a) -5 (e) Suo Shi with the difference of above-mentioned preparation method
Electric layer, other same steps repeat no more.
Relative to the prior art, the utility model has used double piezoelectric layer structures, utilizes the collocation of two layers of piezoelectricity layer material
It adjusts the mechanical-electric coupling ability of SAW device, so as to improve the frequency of device under the conditions of identical lithographic line width, reduces photoetching
Technology difficulty.
Although the technical solution of utility model is described in detail in specific embodiment of the present invention, this reality
With novel without being limited thereto, those skilled in the art of the present technique can be carry out various modifications with principle according to the present utility model.Therefore, it is all
The modification made according to the utility model principle all should be understood to fall into the scope of protection of the utility model.
Claims (10)
1. a kind of RF MEMS filters, which is characterized in that including：
First piezoelectric layer；
The metal electrode being arranged on first piezoelectric layer；
The dielectric layer being filled between the metal electrode；And
The second piezoelectric layer being set on the metal electrode and the dielectric layer.
2. RF MEMS filters according to claim 1, which is characterized in that further include on second piezoelectric layer
Temperature compensating layer.
3. RF MEMS filters according to claim 1, which is characterized in that the material of the metal electrode for tungsten, silver,
One of zirconium, molybdenum, platinum platinum, ruthenium, iridium, titanium tungsten, copper, titanium, chromium, hafnium, aluminium.
4. RF MEMS filters according to claim 1, which is characterized in that Jie being filled between the metal electrode
Matter layer material is silica or silicon nitride.
5. RF MEMS filters according to claim 2, which is characterized in that the temperature compensating layer is thin for silica
Film.
6. RF MEMS filters according to claim 1, which is characterized in that first piezoelectric layer and second pressure
The material of electric layer is identical.
7. RF MEMS filters according to claim 1, which is characterized in that first piezoelectric layer and second pressure
The material of electric layer differs.
8. RF MEMS filters according to claim 1, which is characterized in that the material of first piezoelectric layer is niobic acid
One of lithium, lithium tantalate, aluminium nitride, lead zirconate titanate, zinc oxide.
9. RF MEMS filters according to claim 1, which is characterized in that the material of second piezoelectric layer is niobic acid
One of lithium, lithium tantalate, aluminium nitride, lead zirconate titanate, zinc oxide.
10. RF MEMS filters according to claim 1, which is characterized in that the metal electrode is interdigital structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820031280.6U CN207475507U (en) | 2018-01-08 | 2018-01-08 | RF MEMS filters |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820031280.6U CN207475507U (en) | 2018-01-08 | 2018-01-08 | RF MEMS filters |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207475507U true CN207475507U (en) | 2018-06-08 |
Family
ID=62257652
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820031280.6U Active CN207475507U (en) | 2018-01-08 | 2018-01-08 | RF MEMS filters |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207475507U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107979353A (en) * | 2018-01-08 | 2018-05-01 | 杭州左蓝微电子技术有限公司 | RF MEMS filters and preparation method thereof |
| CN109613647A (en) * | 2019-01-10 | 2019-04-12 | 济南晶正电子科技有限公司 | A kind of lithium niobate/nitridation silicon optical waveguide integrated morphology and preparation method thereof |
-
2018
- 2018-01-08 CN CN201820031280.6U patent/CN207475507U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107979353A (en) * | 2018-01-08 | 2018-05-01 | 杭州左蓝微电子技术有限公司 | RF MEMS filters and preparation method thereof |
| CN109613647A (en) * | 2019-01-10 | 2019-04-12 | 济南晶正电子科技有限公司 | A kind of lithium niobate/nitridation silicon optical waveguide integrated morphology and preparation method thereof |
| CN109613647B (en) * | 2019-01-10 | 2020-05-05 | 济南晶正电子科技有限公司 | Lithium niobate/silicon nitride optical waveguide integrated structure and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107979353A (en) | RF MEMS filters and preparation method thereof | |
| CN102075161B (en) | Acoustic wave device and manufacturing method thereof | |
| CN109217841B (en) | Film bulk acoustic wave combined resonator based on acoustic surface wave and cavity | |
| CN107493086A (en) | Temperature-compensating SAW resonator and preparation method thereof | |
| CN109245742A (en) | One kind combining resonator based on surface acoustic wave and solid reflecting layer film bulk acoustic | |
| CN109150135A (en) | Thin film bulk acoustic wave resonator and its processing method based on bonding | |
| CN106961258A (en) | A kind of cavity type SAW resonator and its processing method | |
| CN106788306A (en) | A kind of FBAR and preparation method thereof | |
| CN108900173A (en) | It is a kind of using silicon as the thin film bulk acoustic wave resonator preparation method of sacrificial layer | |
| US11349450B2 (en) | Symmetric transversely-excited film bulk acoustic resonators with reduced spurious modes | |
| CN207460113U (en) | The thin film bulk acoustic wave resonator combined based on solid-state and cavity | |
| WO2022083352A1 (en) | Bulk acoustic resonator and assembly, filter, and electronic device | |
| CN207475507U (en) | RF MEMS filters | |
| CN108880500A (en) | The production method and radio-frequency filter of radio-frequency filter | |
| CN110350885A (en) | A kind of filter and preparation method thereof | |
| CN107171654A (en) | The FBAR and processing method combined based on solid-state and cavity | |
| CN208924202U (en) | One kind combining resonator based on surface acoustic wave and solid reflecting layer film bulk acoustic | |
| JP2001177365A (en) | Adjustment method for center frequency of balanced filter and plural balanced filters | |
| CN114614792A (en) | Acoustic wave resonator and filter | |
| EP1471636A1 (en) | Film bulk acoustic resonator having an air gap and a method for manufacturing the same | |
| CN208768044U (en) | Thin film bulk acoustic wave resonator based on bonding | |
| CN114978090A (en) | Bulk acoustic wave filter, communication device, and method for manufacturing bulk acoustic wave filter | |
| WO2024061071A1 (en) | Bulk acoustic wave resonance apparatus and method for forming same | |
| CN206542385U (en) | FBAR and communication device with supporting construction | |
| CN207853857U (en) | A kind of SAW resonator based on solid reflecting layer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |