Utility model content
The main purpose of the utility model is to provide a kind of filters, are needed with solving parallel resonator in the related technology
The problem of processing step caused by multilayer mass-loading layer increases.
To achieve the goals above, one side according to the present utility model provides a kind of filter, including at least one
A series resonator and at least two parallel resonators, the parallel resonator or the series resonator include:Mass loading
Layer, wherein the density of the mass-loading layer is adjustable.
Further, the filter includes the first parallel resonator and the second parallel resonator, and described second is in parallel humorous
Shake device mass-loading layer density be more than first parallel resonator mass-loading layer density, wherein the quality
The density of load layer=resonator effective coverage is improved quality load area/resonator effective coverage gross area.
Further, the mass-loading layer is made of the adjustable pattern of pattern density.
Further, the mass-loading layer is made of equidistant striped.
Further, the duty ratio of the striped of second parallel resonator is more than the striped of first parallel resonator
Duty ratio.
Further, the mass-loading layer is made of grid.
Further, the density of the mass-loading layer grid of second parallel resonator is more than first parallel resonance
The density of the mass-loading layer grid of device.
Further, the parallel resonator further includes:First electrode;Piezoelectric layer, the piezoelectric layer are located at described first
Between electrode and second electrode;Second electrode, wherein the mass-loading layer is located on the second electrode.
Further, the parallel resonator further includes:Substrate;The acoustic reflector of formation is deposited over the substrate.
Further, the parallel resonator further includes:Substrate;The cavity of formation is etched over the substrate.
Further, the series resonator and the parallel resonator are that thin film bulk acoustic wave resonator or solid-state fill
With resonator.
Further, the filter further includes:Inductance is connected with the parallel resonator.
In the embodiment of the present application, filter includes at least one series resonator and at least two parallel resonators, and
It includes mass-loading layer to join resonator or series resonator, and the density of mass-loading layer is adjustable, by adjusting mass-loading layer
Density can achieve the effect that adjust resonant frequency offset, reach resonator and only need one layer of mass-loading layer
The effect for adjusting the resonant frequency of resonator in filter, solves resonator in the prior art and multilayer mass-loading layer is needed to lead
The problem of processing step of cause increases.
Specific implementation mode
It should be noted that in the absence of conflict, the features in the embodiments and the embodiments of the present application can phase
Mutually combination.The utility model will be described in detail below with reference to the accompanying drawings and embodiments.
In order to make those skilled in the art more fully understand application scheme, below in conjunction in the embodiment of the present application
Attached drawing, technical solutions in the embodiments of the present application are clearly and completely described, it is clear that described embodiment is only
The embodiment of the application part, instead of all the embodiments.Based on the embodiment in the application, ordinary skill people
The every other embodiment that member is obtained without making creative work should all belong to the model of the application protection
It encloses.
The utility model embodiment provides a kind of filter, which includes at least one series resonator and at least
Two parallel resonators, parallel resonator or series resonator include:Mass-loading layer, wherein the density of mass-loading layer can
It adjusts.
In the embodiment of the present application, filter includes at least one series resonator and at least two parallel resonators, and
It includes mass-loading layer to join resonator or series resonator, and the density of mass-loading layer is adjustable, by adjusting mass-loading layer
Density can achieve the effect that adjust resonant frequency offset, reach resonator and only need one layer of mass-loading layer
The effect for adjusting the resonant frequency of resonator in filter, solves resonator in the prior art and multilayer mass-loading layer is needed to lead
The problem of processing step of cause increases.
Simultaneously as processing step is reduced, the acceptance rate of performance of filter and product is improved.
Optionally, filter includes the first parallel resonator and the second parallel resonator, the quality of the second parallel resonator
The density of load layer is more than the density of the mass-loading layer of the first parallel resonator, wherein density=resonance of mass-loading layer
Device effective coverage is improved quality the load area/resonator effective coverage gross area=mass loading density.
First parallel resonator and the second parallel resonator are two resonators of parallel connection.According to mass loading density formula
It is found that the density if necessary to adjust mass-loading layer, then can be improved quality load area by adjusting resonator effective coverage
To realize.
Optionally, mass-loading layer is made of the adjustable pattern of pattern density, such as grid, striped etc..
Optionally, mass-loading layer is made of equidistant striped.It is made of equidistant striped in mass-loading layer
In the case of, the duty ratio of the striped of the second parallel resonator is more than the duty ratio of the striped of the first parallel resonator.Striped accounts for
Empty ratio is bigger, and resonator effective coverage load area of improving quality is bigger, to which the density of mass-loading layer is also bigger.
Optionally, mass-loading layer is made of grid.In the case where mass-loading layer is made of grid, second is in parallel humorous
Shake device mass-loading layer grid density be more than the first parallel resonator mass-loading layer grid density.The density of grid
Bigger, resonator effective coverage load area of improving quality is bigger, to which the density of mass-loading layer is also bigger.
Mass-loading layer can also be made of the adjustable pattern of other pattern densities other than grid, striped, principle
Identical, details are not described herein.
Fig. 2 is the schematic diagram according to a kind of optional filter of the embodiment of the present application.
As shown in Fig. 2, filter 200 is made of three series resonators 230 and two parallel resonators 210,220.Its
In, thin film bulk acoustic wave resonator (FBAR), solid-state assembly resonator (SMR) may be used in series resonator and parallel resonator.
In addition, filter 200 further includes the inductance of ground connection, wherein the inductance is connected with parallel resonator 210,220 respectively, these
The inductance of ground connection can form transmission zero with parallel resonator 210,220, and the stopband to improve filter 200 inhibits, together
When can also extended filtering device bandwidth.
The sectional view and top view of series resonator 230 and two parallel resonators 210,220 have also been drawn in Fig. 2, are gone here and there
Joining resonator 230 includes:Substrate 201;The cavity 232 of formation is etched on substrate;First electrode 236;Piezoelectric layer 235;Second
Electrode 233.The material of substrate 201 includes but not limited to silicon, glass, sapphire, GaAs etc..The material of first electrode and second electrode
Material includes but not limited to molybdenum, tungsten, aluminium etc..Piezoelectricity layer material includes but not limited to aluminium nitride (AlN), zinc oxide (ZnO), PZT etc.
Material.Parallel resonator 210 includes:Substrate 201;The cavity 212 of formation is etched on substrate;First electrode 216;Piezoelectric layer
215;Second electrode 213;Mass-loading layer 214.Mass-loading layer 214 is made of equidistant striped, and the duty ratio of striped is
D1.Because load layer 214 is so that the thickness of resonator second electrode 213 increases, therefore the resonant frequency of resonator 210 compares resonance
The resonant frequency of device 230 is low.Parallel resonator 220 includes:Substrate 201;The cavity 222 of formation is etched on substrate;First electricity
Pole 226;Piezoelectric layer 225;Second electrode 223;Mass-loading layer 224.Mass-loading layer 224 is made of equidistant striped, item
The duty ratio of line is D2.Because of D2>The mass loading density of D1, mass-loading layer 224 are negative more than the quality of mass-loading layer 214
Density is carried, therefore the resonant frequency of resonator 220 is lower than the resonant frequency of resonator 210.The present embodiment is negative by adjusting quality
The density of carrier layer mass loading can achieve the purpose that adjust parallel resonator frequency shift (FS).The density of mass loading is defined as:
The density of mass-loading layer=mass loading density=resonator effective coverage load area/resonator of improving quality has
Imitate the region gross area.
Fig. 3 is the schematic diagram according to a kind of optional filter of the embodiment of the present application.
As shown in figure 3, filter 300 is made of three series resonators 330 and two parallel resonators 310,320.Its
In, thin film bulk acoustic wave resonator (FBAR), solid-state assembly resonator (SMR) may be used in series resonator and parallel resonator.
In addition, filter 300 further includes the inductance of ground connection, wherein the inductance is connected with parallel resonator 310,320 respectively, these
The inductance of ground connection can form transmission zero with parallel resonator 310,320, and the stopband to improve filter 300 inhibits, together
When can also extended filtering device bandwidth.
The sectional view and top view of series resonator 330 and two parallel resonators 310,320 have also been drawn in Fig. 3, are gone here and there
Joining resonator 330 includes:Substrate 301;The cavity 332 of formation is etched on substrate;First electrode 336;Piezoelectric layer 335;Second
Electrode 333.The material of substrate 301 includes but not limited to silicon, glass, sapphire, GaAs etc..The material of first electrode and second electrode
Material includes but not limited to molybdenum, tungsten, aluminium etc..Piezoelectricity layer material includes but not limited to aluminium nitride (AlN), zinc oxide (ZnO), PZT etc.
Material.Parallel resonator 310 includes:Substrate 301;The cavity 312 of formation is etched on substrate;First electrode 316;Piezoelectric layer
315;Second electrode 313;Mass-loading layer 314.Equidistant square areas is the place of massless load in Fig. 3.Quality is negative
The mass loading density of carrier layer 314 is set as A1.Because load layer 314 is so that the thickness of resonator second electrode 313 increases, therefore
The resonant frequency of resonator 310 is lower than the resonant frequency of resonator 330.Parallel resonator 320 includes:Substrate 301;On substrate
Etch the cavity 322 formed;First electrode 326;Piezoelectric layer 325;Second electrode 323;Mass-loading layer 324.In Fig. 3 equidistantly
Square areas be massless load place.The mass loading density of mass-loading layer 324 is set as A2, and A2>A1, quality are negative
The mass loading density of carrier layer 324 is more than the mass loading density of mass-loading layer 314, therefore the resonant frequency of resonator 320
Resonant frequency than resonator 310 is low.
Fig. 4 is the schematic diagram according to a kind of optional filter of the embodiment of the present application.
As shown in figure 4, filter 400 is made of three series resonators 430 and two parallel resonators 410,420.Its
In, thin film bulk acoustic wave resonator (FBAR), solid-state assembly resonator (SMR) may be used in series resonator and parallel resonator.
In addition, filter 400 further includes the inductance of ground connection, wherein the inductance is connected with parallel resonator 410,420 respectively, these
The inductance of ground connection can form transmission zero with parallel resonator 410,420, and the stopband to improve filter 400 inhibits, together
When can also extended filtering device bandwidth.
The sectional view and top view of series resonator 430 and two parallel resonators 410,420 have also been drawn in Fig. 4, are gone here and there
Joining resonator 430 includes:Substrate 401;Deposit on substrate the acoustic reflection mirror 439,439 of formation by film 431,432,
433,434,435 composition, wherein 431,433,435 be low acoustic impedance material, such as silica.432,434 be acoustic impedance material
Material, such as tungsten;First electrode 436;Piezoelectric layer 435;Second electrode 433.The material of substrate 401 includes but not limited to silicon, glass, indigo plant
Jewel, GaAs etc..The material of first electrode and second electrode includes but not limited to molybdenum, tungsten, aluminium etc..Piezoelectricity layer material includes but not
It is limited to the materials such as aluminium nitride (AlN), zinc oxide (ZnO), PZT.Parallel resonator 410 includes:Substrate 401;It deposits on substrate
The acoustic reflection mirror 419,419 of formation is made of film 411,412,413,414,415.Wherein 411,413,415 is in a low voice
Impedance material, such as silica.412,414 be high acoustic impedance materials, such as tungsten;First electrode 416;Piezoelectric layer 415;Second electrode
413;Mass-loading layer 414.Equidistant square areas is the place of massless load in Fig. 4.Between mass-loading layer 414 is by waiting
Away from striped composition, the duty ratio of striped is D1.Because load layer 414 makes the thickness of resonator second electrode 413 increase, because
The resonant frequency of this resonator 410 is lower than the resonant frequency of resonator 430.Parallel resonator 420 includes:Substrate 401;In substrate
The acoustic reflection mirror 429,429 that upper deposition is formed is made of film 421,422,423,424,425.Wherein 421,423,425
For low acoustic impedance material, such as silica.422,424 be high acoustic impedance materials, such as tungsten;First electrode 426;Piezoelectric layer 425;The
Two electrodes 423;Mass-loading layer 424.Mass-loading layer 424 is made of equidistant striped, and the duty ratio of striped is D2.Because
D2>D1, the mass loading density of mass-loading layer 424 are more than the mass loading density of mass-loading layer 414, therefore resonator
420 resonant frequency is lower than the resonant frequency of resonator 410.
Fig. 5 is the schematic diagram according to a kind of optional filter of the embodiment of the present application.
As shown in figure 5, filter 500 is by three series resonators 530,540 and two 510,520 groups of parallel resonators
At.Wherein, thin film bulk acoustic wave resonator (FBAR), solid-state assembly resonator may be used in series resonator and parallel resonator
(SMR).In addition, filter 500 further includes the inductance of ground connection, wherein the inductance is connected with parallel resonator 510,520 respectively
It connects, the inductance of these ground connection can form transmission zero with parallel resonator 510,520, to improve the stopband of filter 500
Inhibit, at the same can also extended filtering device bandwidth.
The sectional view and top view of series resonator 530,540 and two parallel resonators 510,520 have also been drawn in Fig. 3
In, series resonator 530 includes:Substrate 501;The cavity 532 of formation is etched on substrate;First electrode 536;Piezoelectric layer 535;
Second electrode 533.The material of substrate 501 includes but not limited to silicon, glass, sapphire, GaAs etc..First electrode and second electrode
Material include but not limited to molybdenum, tungsten, aluminium etc..Piezoelectricity layer material include but not limited to aluminium nitride (AlN), zinc oxide (ZnO),
The materials such as PZT.Parallel resonator 510 includes:Substrate 501;The cavity 512 of formation is etched on substrate;First electrode 516;Pressure
Electric layer 515;Second electrode 513;Mass-loading layer 514.Equidistant square areas is the place of massless load in Fig. 5.Matter
The mass loading density of amount load layer 514 is set as A1.Because load layer 514 makes the thickness of resonator second electrode 513 increase,
Therefore the resonant frequency of resonator 510 is lower than the resonant frequency of resonator 530.Parallel resonator 520 includes:Substrate 501;It is serving as a contrast
The cavity 522 of formation is etched on bottom;First electrode 526;Piezoelectric layer 525;Second electrode 523;Mass-loading layer 524.Fig. 3 is medium
The square areas of spacing is the place of massless load.The mass loading density of mass-loading layer 524 is set as A2, and A2>A1, matter
The mass loading density for measuring load layer 524 is more than the mass loading density of mass-loading layer 514, therefore the resonance of resonator 520
Frequency is lower than the resonant frequency of resonator 510.Series resonator 540 includes:Substrate 501;The cavity of formation is etched on substrate
542;First electrode 546;Piezoelectric layer 545;Second electrode 543;Mass-loading layer 544.The mass loading of mass-loading layer 544 is close
Degree is set as A3.Because load layer 514 makes the thickness of resonator second electrode 513 increase, therefore the resonant frequency of resonator 540
Resonant frequency than resonator 530 is low.Usually, A2>A1>A3.
The embodiment of the present application is not in the case where introducing additional manufacturing process, by adjusting mass-loading layer mass loading
Density can achieve the purpose that adjust parallel resonator frequency shift (FS), it is only necessary to which one layer of mass-loading layer can be adjusted arbitrarily
The resonant frequency of any resonator in filter.And in traditional technical solution, to realize the resonator of several different frequencies
With regard to needing the mass-loading layer of identical quantity.Therefore, filter manufacturing process provided by the embodiments of the present application is simpler, cost
It is lower.
It these are only embodiments herein, be not intended to limit this application.To those skilled in the art,
The application can have various modifications and variations.It is all within spirit herein and principle made by any modification, equivalent replacement,
Improve etc., it should be included within the scope of claims hereof.