CN102101636B - Resonator and periodic structure - Google Patents
Resonator and periodic structure Download PDFInfo
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- CN102101636B CN102101636B CN200910259221XA CN200910259221A CN102101636B CN 102101636 B CN102101636 B CN 102101636B CN 200910259221X A CN200910259221X A CN 200910259221XA CN 200910259221 A CN200910259221 A CN 200910259221A CN 102101636 B CN102101636 B CN 102101636B
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Abstract
The invention discloses a resonator, which at least consists of a resonance body and at least one periodic structure. One end of the periodic structure is connected with the resonance body, and the periodic structure at least consists of two repeated basic structural units; and the periodic structure can be used for blocking wave propagation generated when the resonance body shakes, wherein the resonance body has the resonance frequency of f0; the periodic structure has a frequency gap characteristic or dumb frequency characteristic in a specific frequency range; and the resonance frequency of f0 is in the specific frequency range of the periodic structure.
Description
Technical field
The present invention relates to a kind of resonator, in particular to a kind of resonator with periodic structure.
Background technology
MEMS (Micro Electro Mechanical System, MEMS) technology is to make the electric mechanical mechanism assembly at silicon wafer substrate, it can realize the function that in the past can't obtain.
Along with the globalised economy development; And demand mobile and wireless, multi-media communication; Various wireless telecommunications such as Global System for Mobile Communication (Global System for Mobile Communications; GSM), bluetooth (Bluetooth), WLAN (Wireless LAN; WLAN), the third generation according to moving mechanics of communication (3rd-generation, 3G), the global intercommunication microwave access (WorldwideInteroperability for Microwave Access, WiMAX) wait flourish in the past few years.The standard or the frequency range that are applied at present in the wireless telecommunications have reached more than seven kinds, and each standard all has its unique communications protocol (protocol), like different frequency band (band), different channel width (channelbandwidth) ... etc.).Connect for reaching seamless communication, therefore following mobile phone will be set with different communication systems with the adjustable high-frequency front-end module, realize the system architecture of restructuring (reconfigurable).
And after the wireless telecommunication system high frequencyization, the MEMS assembly process technology of utilizing silicon wafer substrate to make can be produced the high-frequency circuit of miniaturization, cost degradation, modularization, singulation (Monolithic), and will more be paid attention to future.
(gigahertz, GHz) under the frequency, its loss will increase along with frequency conventional radio frequency (radio frequency) assembly in gigahertz because of conductor and medium.Therefore, with the bulk acoustic wave resonator of mechanism's resonance mode (Film Bulk Acoustic-wave Resonator, FBAR); Because of having little and high quality factor (the quality factor of volume; Q) advantage will replace associated component gradually, and become the primary clustering of mobile phone with filter.But present business-like bulk acoustic wave resonance filter is when 1GHz, and quality factor Q value is about 800～1200, only is fit to do Frequency Band Selection filter (Band Selective Filter).Satisfy time adjustable channel selection high frequency front-end module of generation if will develop " channel selecting filter (Channel Selective Filter) "; Then need ask radio-frequency micro electromechanical resonator (RF MEMS resonators) will reach more than 10,000 in the Q of 1GHz value.Therefore, how designing the resonator of high Q value, and then reach the target of channel selection filter, is the ultimate challenge that present research staff in the world faces.
How increase aspect the product of frequency-quality factor (f-Q), existing international research and development unit is a target from how reducing the loss of resonator in a resonance cycle all.The known resonance body loss mechanism of document can be obtained by formula at present:
Q
Air: air damping (air damping)
Q
TED: the thermoelastic damping (thermoelastic damping, TED)
Q
Support: support loss (support loss)
Q
Surface: surface loss (surface loss)
Generally speaking; The loss project of air damping (air damping) can be left in the basket in vacuum (or low pressure) system; Surface loss (surface loss) also can be ignored at the mechanical structure resonator; Therefore (thermoelastic damping is TED) with two factors of support loss (support loss) to the most important thing is to consider the thermoelastic damping.Above-mentioned two main loss and frequencies at the high frequency micro electromechanical structure have correlation.Existing relevant scholar in document (respectively with theoretical and experiment) proposition under high frequency (＞100MHz); Supporting loss (support loss) will be the main cause that resonator Q value can't promote; Therefore some academic units and international microcomputer TV university factory all drop into the analytical calculation of support loss; And propose different patented technologies, avoid the elastic force ripple to see through brace summer (support beam) and be passed to substrate, to promote the Q value.
Traditional resonator structure is that the resonance body is erected on the substrate with brace summer, and resonance body, brace summer (support beam) and substrate be commaterial for example the silicon material process, its acoustic impedance (suc as formula (1)) is in full accord.Vibrational energy is easy to transmit on same material.Therefore the elastic force ripple of body of resonating be passed to behind the brace summer with areflexia ground near 100% loss on base material.
Below be to propose two kinds of different patented technologies, technology contents all is to avoid the elastic force ripple to see through brace summer to be passed to substrate, reduces loss to promote the Q value.
U.S. Pat 6; 628, No. 177 (hereinafter to be referred as 177 ' patent), name is called " Micromechanicalresonator device and micromechanical device utilizing same "; It proposes a kind of micro electronmechanical resonance assembly, and is as shown in Figure 1.The technological means of 177 ' patent mainly is to be the body of dish shape (Disk) resonator with a growth diamond film, utilizes the sound impedance of two kinds of different materials different, and diamond (Diamond) is respectively 6.18*10 with the sound impedance of silicon
7Kg/m
2/ s, 1.85*10
7Kg/m
2Therefore/s produces elastic force wave reflection face, with bulk wave reflected back resonance body, and forms high quality factor (High-Q) resonator.The resonator structure of Fig. 1 mainly comprises diamond dish shape resonance body (diamond disk) 101, polysilicon column thing (polysilicon stem) 102, tubercle ring (nodal ring) 104; Meeting reflected back resonance body when sound wave (acoustic wave) runs into the interface 105 of diamond and silicon, so interface 105 is again the acoustic reflection face.Wherein diamond is the maximum reflecting surface material of occurring in nature sound impedance.
The experimental data of 177 ' patent also is published on U.S. electric appliance and electronic IEEE (IEEE) periodical in 2004, tabulates shown in 1 as follows.Can know that from table 1 diamond film is that the Q value of dish shape resonator can significantly promote more than six times
Table 1
| Module (Mode) | The material of column (Stem Material) | The material (Disk Material) of dish shape resonance body | The diameter of column (Stem Diam., μ m) | The diameter (Disk Diam., μ m) of dish shape resonance body | Frequency (Res. Freg., MHz) | Quality factor q (Quality Factor) |
| First module | Silicon | Silicon | 1.6 | 22.0 | 245.1 | ?8,100 |
| First module | Silicon | Diamond | 1.6 | 22.0 | 497.58 | ?55,300 |
Though use different materials can produce elastic force wave reflection face, and use diamond film can deal with all frequency ranges with reflected energy.
No. 7,295,088, another U.S. Pat (hereinafter to be referred as 088 ' patent), title " High-Qmicromechanical resonator devices and filters utilizing same ", it proposes another kind of micro electronmechanical resonance assembly, and is as shown in Figure 2.Wherein, micro electronmechanical resonance assembly mainly is to comprise annular resonance body 201, the central strong point 202 and cross brace summer 203.Annular resonance body 201 has hollow bulb (central cavity); Central authorities' strong point 202 is positioned at the center of the hollow bulb of annular resonance body 201, and the interior ring with annular resonance body 201 links to support resonance body 201 to external radiation ground from the central strong point 202 for 203 of cross brace summers.And the outside and the inboard of annular resonance body 201 are respectively equipped with sensing electrode (sense electrode) 205 and drive electrode (drive electrode) 206, make whole supporting construction more interference-free by electrode is overlapping, to reach high Q value and low-impedance effect.
Use diamond and two kinds of different materials of silicon unlike 177 ' patent; This 088 ' patent is exposed: material parameter identical (body 201 that promptly resonates, the central strong point 202 and cross brace summer 203 are same material) down; Cross brace summer 203 is linked to substrate, can be considered dead short circuit phenomenon (being that impedance is mated fully).But elongated gradually during to quarter-wave when the length of cross brace summer 203, because of deformation one end is maximum, the other end be minimum, so its impedance can be considered least matching state, can reflect maximum energy and return the body 201 that resonates.Therefore the technical characterstic of 088 ' patent mainly is: when the length of cross brace summer 203 was (2n+1) times of quarter-wave or wavelength, the Q value of resonance assembly as shown in Figure 2 was the highest (when the frequency 1.2GHz, Q value about 14,643).
Therefore, how with the compatible situation of existing micro electronmechanical processing procedure under, develop resonator with high quality factor, make it have superelevation f-Q product, break through international existing bottleneck, real important goal of making great efforts to research and develop for one of ordinary skill in the art.
Summary of the invention
According to the present invention, a kind of resonator is proposed, it is made up of with at least one periodic structure the resonance body at least.One end of periodic structure links the resonance body, and is made up of two basic structural units that repeat at least.The ripple that periodic structure is produced when can be used for stopping the concussion of resonance body passes.
According to the present invention, a kind of periodic structure is also proposed, it uses micro electronmechanical manufacture process manufacturing, and periodic structure comprises an one dimension periodic structure body, and the periodic structure body is made up of a basic structural unit at least.Basic structural unit is taken from the periodically platy structure of hole of tool two-dimensional crystal lattice, basic structural unit in one dimension direction repeated arrangement to form one dimension periodic structure body.Wherein, the acquisition mode of basic structural unit is the shape that four orthogonal geometry lines of cut are surrounded out on the platy structure with two-dimensional crystal lattice periodicity hole, and four how much lines of cut can be through the inside of periodicity hole.
For letting the foregoing of the present invention can be more obviously understandable, hereinafter is special lifts preferred embodiment, and conjunction with figs. elaborates.
Description of drawings
Fig. 1 is the sketch map of the micro electronmechanical resonance assembly of a kind of tradition, wherein is the body of dish shape (Disk) resonator with the growth diamond film;
Fig. 2 is the sketch map of another kind of traditional micro electronmechanical resonance assembly;
Fig. 3 is the sketch map according to a kind of resonator of first embodiment of the invention;
Fig. 4 A is the top view of the another kind of resonator of first embodiment of the invention;
Fig. 4 B is the end view shown in Fig. 4 A;
Fig. 5 A is in the periodic structure of first embodiment of the invention, has the sketch map of a basic structural unit of hexagon lattice defective framework;
Fig. 5 B is the hexagon lattice defective of Fig. 5 A, the dispersion curve figure of periodic structure under specific dimensions of one dimension;
Fig. 6 A is in the periodic structure of first embodiment of the invention, has the sketch map of a basic structural unit of square lattice defect framework;
Fig. 6 B is the square lattice defect of Fig. 6 A, the dispersion curve figure of periodic structure under specific dimensions of one dimension;
Fig. 7 is the sketch map according to another resonator of first embodiment of the invention;
Fig. 8 A is the top view according to a kind of resonator of second embodiment of the invention;
Fig. 8 B is that resonator with Fig. 8 A is at the prepared dispersion curve figure of the periodic structure under the specific dimensions;
The energy that Fig. 9 A shows the resonator of emulation aperiodicity structure penetrates analysis ripple biography result;
The foam stability ripple that Fig. 9 B shows the resonator of simulating the periodic structure with hexagonal lattice defective, one dimension passes the result;
The foam stability ripple that Fig. 9 C shows the resonator of simulating the periodic structure with tetragonal defective, one dimension passes the result;
Figure 10 shows and adds periodic structure and the elastic wave biography behavior comparable situation that does not add periodic structure;
Figure 11 is the graph of a relation of resonance frequency and SiBAR structure width;
Figure 12 has provided the relevant enforcement data of some design sizes.
Description of reference numerals
101: diamond dish shape resonance body
102: polysilicon column thing
104: the tubercle ring
105: interface
201: annular resonance body
202: the central strong point
203: the cross brace summer
205: sensing electrode
206,310: drive electrode
31,41,71: base material
301,401,701,801: the resonance body
303,403,703,803: brace summer
304,404,704,804: periodic structure
406,706,806: the strong point (is " strong point 806 " because a place is arranged in embodiment 2)
Embodiment
The present invention proposes a kind of resonator structure, it comprises a resonance body and an one-period property structure at least.Periodic structure one end links the resonance body, and is made up of two basic structural units that repeat at least.According to embodiment proposed by the invention, when the concussion of resonance body, periodic structure can reflect elastic force wave resistance retaining ripple and pass, and ripple is passed let out and can reduce, and the quality factor q of resonator is improved.Moreover the embodiment of the invention can be compatible mutually with existing micro electronmechanical manufacture process.
Related embodiment more of the present invention are below proposed.Yet the resonator structure that is proposed among the embodiment is merely and illustrates, and the scope of unrestricted desire protection of the present invention.Moreover the diagram among the embodiment has also been omitted the more existing assembly that does not relate to the present invention's design, in order to clear demonstration technical characterstic of the present invention.
First embodiment
Fig. 3 is the sketch map of a kind of resonator of first embodiment of the invention.Resonator comprises resonance body 301 and one-period property structure 304 at least.In first embodiment, resonator comprises the brace summer 303 that links resonance body 301 and periodic structure 304; And have each one group of brace summer 303 and periodic structure 304 respectively at the two ends of resonance body 301, as shown in Figure 3.
Resonance body 301 can be blocks such as square, rectangle, rectangle, circle or annular, does not limit shape is concrete.In this embodiment, resonance body 301 is the rectangle block, and is interposed between two drive electrodes 310 to make resonator.Drive electrode 310 has the gap with the wall of resonance body 301, for example is the spacing of tens nanometers (nm), and the mode that sees through electrostatic force makes resonance body 301 produce resonance.But the body 301 that wherein resonates has resonance frequency f under operation mode
0, and periodic structure 304 has ditch characteristic or mute characteristic frequently frequently in special frequency, the resonance frequency f of resonance body 301
0Drop in the middle of this special frequency of the periodic structure 304 that is designed.Periodic structure 304 passes professional domain in elastic wave and is called phonon crystal (phononic crystal) again, can stop the elastic force ripple/mechanical wave that transmits from the body 301 that resonates.
Please be simultaneously with reference to Fig. 4 A, 4B.Fig. 4 A is the top view of the another kind of resonator of first embodiment.Fig. 4 B is the end view of Fig. 4 A.Wherein, Resonator links except the end that the side at resonance body 401 sees through brace summer 403 and periodic structure 404; The other end of periodic structure below is arranged on the base material 41 with the strong point (anchor) 406, makes resonance body 401, brace summer 403 and periodic structure 404 formation one distance all and between the base material 41.Equally, respectively have one group of brace summer 403 and periodic structure 404 at the two ends of resonance body 401 among Fig. 4 A, the 4B, its structure general (but not restrictedly) can be symmetrical kenel.
And micro electronmechanical resonator is when high-frequency operation, and its qualitative factor (quality factor) will be passed to the loss of base material 41 and be determined by the strong point 406.And embodiments of the invention promptly are to utilize periodic structure 404 is placed between resonance body 401 and the base material 41; And design has the phonon crystal that appropriate size can cause tool frequency ditch (band gap); Utilize phonon crystal can reflect the physical characteristic of elastic force ripple; Make energy can't be passed to the strong point 406, reduce the loss that is passed to base material 41, reach high quality factor (High-Q).Therefore to be with the periodic structure be the High-Q resonator of reflecting boundary to the structure shown in Fig. 3,4A, the 4B.This High-Q resonator can be suitable for important spare part--the application of-filter of wireless telecommunication system after integrating.
When making the resonator structure of the embodiment of the invention; Need not use like different materials such as described diamond film of prior art 177 ' patent and silicon; And be to use same material (for example silicon) to produce resonator structure; Therefore can with micro electronmechanical manufacture process (for example CMOS processing procedure) compatibility, can not improve manufacturing cost, be fit to be widely used on the commercial market.Moreover; Look the practical application situation; Can be chosen in any one suitable operation in the micro electronmechanical manufacture process, form the resonator structure of the embodiment of the invention, body and the periodic structure of wherein resonating (and brace summer; If the words that have) can be integrated into single brace summer, shown in Fig. 9 B, 9C with fault of construction.In the present embodiment, resonance body and periodic structure can use same material to make.
In addition, the periodic structure of the embodiment of the invention at least by repeat two or more (as: 3,4 ... p, p is by more than or equal to 2 positive integer) basic structural unit formed.And each basic structural unit for example is one dimension repetition period framework, square crystal lattice framework, hexagon crystal lattice framework or other structure; The present invention also seldom limits; As long as basic structural unit has ditch (Band gap) characteristic or mute frequency range (Deaf band) frequently, and this frequency ditch/mute frequency range has contained the resonance frequency f under the resonator operation mode
0, the elastic force ripple can't be transmitted on periodic structure can be as execution mode of the present invention.
Below, be the explanation of making periodic structure respectively with basic structural unit with hexagon crystal lattice framework and square crystal lattice framework.
Please with reference to Fig. 5 A, 5B.Fig. 5 A is in the periodic structure of first embodiment of the invention, has the sketch map of a basic structural unit of hexagon lattice defective framework.Fig. 5 B is the hexagon lattice defective of Fig. 5 A, the dispersion curve figure of periodic structure under specific dimensions of one dimension.
Among Fig. 5 A, a basic structural unit in the periodic structure has the hexagon crystal lattice framework, i.e. a plurality of holes on the basic structural unit, and the center of circle of these holes takes hexagonal lattice to arrange.
In a design example, if the resonance body is a rectangle resonance block, its physical dimension is height 6 μ m; Width 14 μ m; It is the resonance mode of node (the SiBAR structure that adopts Geogia Tech to deliver) that length 150 μ m, this rectangle resonance block have a length direction central shaft, resonance frequency f
0Be 301.2MHz.The physical dimension of support beam structure is height 6 μ m, length 7 μ m, and the rectangular block of width 2 μ m, for increasing the Q value, an end of brace summer is connected the node location of resonance resonance body mode.Can design a periodic structure of tool, frequency ditch phenomenon or the mute frequency range of utilizing this structure to exist are come the elastic wave of reflection frequency for 301.2MHz.
In addition, Figure 11 is the graph of a relation of resonance frequency and SiBAR structure width, SiBAR length stuck-at-50 μ m wherein, and fixed thickness is at 6 μ m.With the rectangle resonance block phonon crystal of arranging in pairs or groups, under regular length and thickness, just can obtain the necessary operations frequency as long as design the width of this rectangular block.
If hexagon lattice periodic structure shown in Fig. 5 A of design; See through the emulation on single cell respective outer side edges Bragg period property border, can obtain the periodicity single cell structure of feature geometries length for height 6 μ m, hole radius 2.6 μ m, the hole center of circle (adopting hexagonal lattice arranges) spacing 6 μ m.Fig. 5 B is the prepared dispersion curve figure of hexagon lattice periodic structure size according to this.Can learn from Fig. 5 B: this hexagon lattice periodic structure has ditch characteristic frequently at frequency range 268.2MHz to 351.7MHz.When resonance block at resonance frequency f
0When vibrating down for 301.2MHz, its resonance frequency f
0Fall into this ditch frequency range frequently, therefore periodic structure can reflect the elastic force ripple that the self-supporting beam transmits for can not propagate mode, and then avoids energy to reach the loss that base material causes via the strong point of periodic structure below.
Fig. 6 A is in the periodic structure of first embodiment of the invention, has the sketch map of a basic structural unit of square lattice defect framework.Fig. 6 B is the square lattice defect of Fig. 6 A, the dispersion curve figure of periodic structure under specific dimensions of one dimension.
According to the resonance body that above-mentioned design example proposed and the size of brace summer; Also can see through the emulation on single cell respective outer side edges Bragg period property border; The single cell structure of acquisition shown in Fig. 6 A; Its feature geometries length is height 6 μ m, hole radius 6.5 μ m, hole center of circle spacing 15 μ m, and the center of circle of those holes takes tetragonal to arrange.Fig. 6 B then is the prepared dispersion curve figure of square lattice period property physical dimension according to this, and can learn from Fig. 6 B: this square lattice period property structure belongs to mute frequency range to 324MHz with respect to the resonance body size that design example proposed at frequency range 290MHz.When resonance block at resonance frequency f
0When vibrating down for 301.2MHz, its resonance frequency f
0Fall into this mute frequency range, the ripple of periodic structure passes behavior and bridge joint beam oscillation behavior quadrature, therefore can reflect the elastic force ripple that the self-supporting beam transmits, and then avoids energy to reach the loss that base material causes via the strong point of periodic structure below.
Moreover, in the periodic structure, the proportional relation of physical dimension and frequency of operation.For example if the high quality factor resonator of an embodiment designs completion at frequency of operation f
0, structure size is the AxBxC size, as dwindling into 0.5A * 0.5B * 0.5C to said structure t size integral body, frequency of operation will become 2 times of f so
0Otherwise as zooming into 2A * 2B * 2C to said structure t size integral body, frequency of operation will frequency reducing become 1/2 times of f so
0Figure 12 provides the relevant enforcement data of some design sizes, during for practical application as frequency of operation and the reference of selecting the phonon crystal kenel.The body that for example resonates is of a size of wide 32 μ m * length 200 μ m * thickness 6 μ m, frequency of operation when 390MHz, the D type of can arranging in pairs or groups phonon crystal (ditch frequently: 380～400MHz).
And when using the basic structural unit shown in Fig. 5 A or Fig. 6 A, can be with reference to Fig. 3 and Fig. 4 A.Resonator as shown in Figure 3, the periodic structure that links with resonance body one end comprises four hexagon lattice basic structural units (also can change the square lattice period property structure shown in Fig. 6 A into) shown in Fig. 5 A; And the resonator shown in Fig. 4 A, the periodic structure that links with resonance body one end then comprises two basic structural units (also can change the square lattice period property structure shown in Fig. 6 A into) with hexagon crystal lattice framework.Wherein, the basic structural unit of Fig. 3 and Fig. 4 A is all arranged on the one dimension direction, and its arrangement mode can be regarded as 1 * 4 and 1 * 2 matrix kenel respectively.And the included basic structural unit number of periodic structure preferably is at least two, but not special restriction, and the visual application of its actual number is required and do suitably to select.
Connect resonance body and one-period property structure though be brace summer in the above-mentioned execution mode, it should be noted that the present invention, also can omit brace summer and make a periodic structure and an end of the body that resonates directly link not as limit.
In addition; The not special restriction of the periodic structure number that is connected with the resonance body; Except the resonator structure shown in Fig. 3 and Fig. 4 A is that (seeing through brace summer) respectively connects one group of periodic structure at the two ends of resonating body; Also can be connect 3,4 ... r organizes periodic structure (r is a positive integer), and this should look resonator and use kenel and decide with actual demand, and the present invention also seldom limits this.Fig. 7 is the sketch map according to the resonator of another high quality factor of first embodiment of the invention.Wherein, The resonance body 701 of resonator is an annular; And have four groups of periodic structures 704 and see through the node place that brace summer 703 is connected to the resonance body 701 of annular respectively; And other end of each group periodic structure 704 is arranged on the base material 71 with the strong point 706, and resonance body 701, brace summer 703 and the periodic structure 704 of annular all with base material 71 spacing of being separated by.Moreover, resonator as shown in Figure 7, its each group periodic structure 704 comprises that three basic structural units arrange with 1 * 3 matrix kenel, each basic structural unit has the square crystal lattice framework shown in Fig. 6 A.
In addition; During practical application; What be connected with the resonance body of resonator (no matter whether seeing through brace summer) respectively organizes periodic structure; The kenel and the number of the basic structural unit that it comprised can be the same or different, and for example each basic structural unit can comprise a kind of crystal lattice framework or multiple crystal lattice framework identical or inequality; And periodic structure can symmetry also can be asymmetric, the present invention is to this and seldom limit.
In addition, describe, yet the present invention also can be the hole of other shape, for example holes such as rectangle, triangle, ellipse not as limit though in the respective drawings of the foregoing description, all have circular hole with periodic structure; Moreover, except air, also can fill the material with the basic structural unit different materials in the hole, if basic structural unit material silicon for example then can be filled the material beyond tungsten or the silicon in the hole.As long as formed periodic structure has frequently ditch characteristic or mute frequency range, any structure that can reflect the elastic wave that the body that resonates transmits all belongs to the enforceable mode of the present invention.
Second embodiment
In first embodiment, at least two basic structural units of each group periodic structure are arranged on the one dimension direction and made explanation, promptly arrange with 1 * p (p is the positive integer more than or equal to 2) matrix kenel.Yet the present invention is not as limit, and these basic structural units of periodic structure also can be arranged on two-dimensional directional, promptly arranges with m * n matrix kenel, and wherein m and n are respectively the positive integer more than or equal to 2.
Please with reference to Fig. 8 A, it is the top view of a kind of resonator of second embodiment of the invention.Wherein, respectively have one group of brace summer 803 and periodic structure 804 in the both sides of resonance body 801, its structure (but not restrictedly) is symmetrical kenel.With the one-sided of body 801 that resonate; One end of periodic structure 804 sees through brace summer 803 and links with resonance body 801; And the other end of periodic structure below is arranged on the base material (not being shown among Fig. 8 A) with the strong point (anchor) 806, makes resonance body 801, brace summer 803 and periodic structure 804 all and form a distance between the base material.Moreover each group periodic structure 804 included basic structural unit is arranged on two-dimensional directional, promptly arrange with 5 * 4 matrix kenels, and each basic structural unit has square crystal lattice framework, and promptly the center of circle of hole takes tetragonal to arrange.
Fig. 8 B is that resonator with Fig. 8 A is at the prepared dispersion curve figure of the periodic structure under the specific dimensions.This kind periodic structure has ditch characteristic frequently at frequency range 258MHz to 317MHz.When the resonance block of Application Design example at resonance frequency f
0Be 301.2MHz down during vibration (please with reference to first embodiment explanation), its resonance frequency f
0Fall into this ditch frequency range frequently, therefore periodic structure 804 can reflect the elastic force ripple that self-supporting beam 803 transmits, and then avoid energy to reach base material via the strong point 806 of periodic structure 804 belows and cause loss for can not propagate mode.When the high-frequency operation resonator; High quality factor depends on that the strong point 806 is passed to the loss of base material; 804 of the periodic structures that two-dimensional directional shown in Fig. 8 A is arranged are to have the phonon crystal of ditch characteristic frequently; Almost reach perfect reflective boundary condition, and then reach very high quality factor (High-Q).When the frequency of operation of resonator greater than 100MHz, its quality factor can be greater than 10000.
Equally, when practical application, can preferably in certain micro electronmechanical one procedure, once accomplish making, to save cost like the described resonator structure of second embodiment.Moreover resonator structure can select for use other material that can apply in silicon or the micro electronmechanical manufacture process to make.
Comprehensively above-mentioned; Periodic structure; In other words; Comprise at least periodic structure body, and basic structural unit takes from and has the periodically platy structure of hole of two-dimensional crystal lattice by the one dimension that basic structural unit constituted, basic structural unit in one dimension direction repeated arrangement to form the periodic structure body of one dimension.Wherein the acquisition mode of basic structural unit is the shape that four orthogonal geometry lines of cut are surrounded out on the platy structure with two-dimensional crystal lattice periodicity hole, and these how much lines of cut can be through the inside of periodicity hole.Moreover, have certainly two-dimensional crystal lattice periodically this basic structural unit that platy structure captured of hole periodically have ditch or mute frequency characteristic frequently during infinite arrangements in one dimension, make the elastic wave that periodic structure one end from one dimension imports into can't be transmitted to the other end.In addition, the basic structural unit fechtable is from having the platy structure (shown in Fig. 6 A) of two-dimension square lattice hole or having the platy structure of two-dimentional triangular crystal lattice hole or have the platy structure (shown in Fig. 5 A) of two-dimentional hexagonal lattice hole or the platy structure of other shape lattice hole.And the hole on the platy structure can be the cross section of circular cross-section or elliptic cross-section or polygonal cross-section or other shape.
Other can be done suitably adjustment and change under technological concept of the present invention each thin explanation please with reference to the content of first embodiment, is repeated no more at this.
The result of l-G simulation test and explanation
In the l-G simulation test, the resonator with the periodic structure by the reflecting boundary is made up of resonance piece, at least one brace summer and at least one periodic structure.This l-G simulation test has been verified the elastic wave biography behavior of brace summer to this section of substrate zone with numerical value.Owing to can not set up infinitely-great substrate in the l-G simulation test; Therefore connecing with an absorbing material at the substrate right-hand member comes the emulation ripple to reach the infinite distant place of substrate; And when the earthquake of resonance block, can promote brace summer; Therefore on brace summer, give wave source, should connect a resonance block in place's (brace summer) with emulation.
The energy that Fig. 9 A shows the resonator of emulation one aperiodicity structure penetrates analysis ripple biography result.The foam stability ripple of resonator that Fig. 9 B shows the periodic structure of emulation tool hexagonal lattice defective, one dimension passes the result.The foam stability ripple of resonator that Fig. 9 C shows the periodic structure of emulation tool tetragonal defective, one dimension passes the result.Among the 9A～9C figure, M is an absorbing material, and b is a brace summer, and S is a substrate area, and WS is a wave source.Fig. 9 A is control group experiment; The energy that Fig. 9 B, 9C have provided the periodic structure that emulation arranges according to the one dimension direction of first embodiment of the invention penetrates the analysis situation; Can relatively add periodic structure and pass behavior with the elastic wave that does not add periodic structure, elastic wave enters into substrate area and is regarded as ripple biography energy leakage.
Observe these Simulation results, find: do not have the resonator of periodic structure, its elastic force ripple can continue to transmit and get into substrate area, shown in Fig. 9 A.And like the resonator with periodic structure of the embodiment of the invention, use to have the hexagonal lattice periodic structure of ditch characteristic frequently, its elastic force ripple can't continue to transmit, shown in Fig. 9 B.If use the tetragonal periodic structure with mute frequency range, its elastic force ripple disappears after firm entering substrate area is a bit of, therefore also can't continue in substrate area, to transmit, shown in Fig. 9 C.
Figure 10 passes the comparison of behavior for adding periodic structure and the elastic wave that does not add periodic structure.Wherein, elastic wave enters into substrate area and is regarded as ripple biography energy leakage.Equally, among Figure 10, M is an absorbing material, and b is a brace summer, and S is a substrate area, and WS is for giving the wave source position.
Compare from the Simulation results of Figure 10, both differ from more than 100 times in the estimated energy of substrate area approximately, but pass energy leakage viewpoint inference from ripple, have the resonator Q value performance of periodic structure to exceed more than 100 times than the resonator Q value that does not have periodic structure.Compared to so far; Document is to see through diamond resonance block collocation silicon bridge to connect beam (patent 177 ') in the preferably improvement that ripple passes leak suppressing; Utilize two kinds of material acoustic impedances not match and suppress the leakage of ripple biography energy,, have two kinds of unmatched helps of impedance will only can help oppressive 1/4 times ripple biography energy leakage from the acoustic impedance viewpoint; And the present invention has frequently that its acoustic impedance of periodic structure of ditch can be considered infinitely great, just can constrain nearly all ripple and pass energy and reveal.
Certainly, those skilled in the art can estimate that the real resonator assembly of doing still can leak energy (like the loss of material itself) with other form.Therefore, the resonator with periodic structure of the embodiment of the invention can be considered ripple passed to let out can reduce to minimumly, so the performance of Q value will be very high, final experimental Q-value show the thermoelastic damping that only is subject to material itself (Thermoelastic damping, TED).
Comprehensively above-mentioned; The resonator of the embodiment of the invention, with the periodic structure that places between resonance body and base material, and this periodic structure has suitable size and can form and have the phonon crystal of ditch characteristic frequently; Utilize the physical characteristic that phonon crystal can reflect elastic wave to pass to stop the ripple that the resonance body is produced when shaking; Reduce the loss that is passed to base material, reach almost ideal reflective boundary condition, and then reach high quality factor.Moreover the resonator of the embodiment of the invention can use same material (for example silicon) to make, can be compatible with existing micro electronmechanical manufacture process, need not as prior art, use diamond and silicon different materials, and therefore can not increase manufacturing cost.And when using periodic structure (phonon crystal) and producing frequently ditch, the phenomenon that elastic wave can't be transmitted can be regarded as artificial perfect material (prefect boundarycondition) with its characteristic, and it is infinitely great that its acoustic impedance can be considered.
And prove also that according to relevant Simulation results the resulting Q value of resonator with periodic structure of the present invention can significantly be improved, and make the f-Q product have the superelevation value, therefore have the potentiality that break through international prior art bottleneck.The micro electronmechanical resonator of this superior quality factor can be applicable to: legacy frequencies selective filters such as the bulk acoustic wave resonator (FBAR) during the existing mobile phone of (1) replacement uses, SAW....Because of its performance (Q value) is high than conventional filter, and compare no uniform in thickness property consideration with FBAR.(2) it has the Q value of superelevation; Can realize one of following mobile communication solution that international research mechanism proposes---be the radio frequency prime with passage selecting filter (channel select filter); And collocation software-defined radio (Software Defined Radio; SDR), reach seamless communication system.
Table 2 is simply listed the difference of the present invention and two kinds of prior aries and the comparison of features.
Table 2
In sum, though the present invention discloses as above with preferred embodiment, so it is not in order to limit the present invention.Those skilled in the art under the present invention are not breaking away from the spirit and scope of the present invention, can do various changes and retouching.Therefore, protection scope of the present invention should be as the criterion with accompanying claims institute restricted portion.
Claims (35)
1. resonator comprises:
The resonance body has a resonance frequency f
0With
At least one periodic structure, one of which end link said resonance body, and this periodic structure is made up of two basic structural units that repeat at least,
Wherein, said periodic structure has ditch characteristic or mute characteristic frequently frequently in special frequency, and said resonance frequency f
0Drop in the said special frequency of said periodic structure, said periodic structure can be used for stopping that the ripple that said resonance body is produced when shaking passes.
2. resonator as claimed in claim 1, basic structural unit described in the wherein said periodic structure are one dimension cycle framework.
3. resonator as claimed in claim 1, basic structural unit described in the wherein said periodic structure is square crystal lattice framework.
4. resonator as claimed in claim 3, wherein said square crystal lattice framework has a plurality of holes, and the center of circle of these holes takes tetragonal to arrange.
5. resonator as claimed in claim 1, basic structural unit described in the wherein said periodic structure is the hexagon crystal lattice framework.
6. resonator as claimed in claim 5, wherein said hexagon crystal lattice framework has a plurality of holes, and the center of circle of these holes takes hexagonal lattice to arrange.
7. resonator as claimed in claim 1, in the wherein said periodic structure, each basic structural unit comprises a kind of crystal lattice framework.
8. resonator as claimed in claim 1, in the wherein said periodic structure, each basic structural unit comprises two kinds of crystal lattice framework.
9. resonator as claimed in claim 8, wherein said two crystal lattice framework are identical crystal lattice framework.
10. resonator as claimed in claim 8, wherein said two crystal lattice framework are different crystal lattice framework.
11. resonator as claimed in claim 1, the said basic structural unit of wherein said periodic structure is arranged on the one dimension direction.
12. resonator as claimed in claim 11, wherein said basic structural unit is arranged with m * n matrix kenel, m=1 wherein, and n is the positive integer more than or equal to 2.
13. resonator as claimed in claim 1, the said basic structural unit of wherein said periodic structure is arranged on two-dimensional directional.
14. resonator as claimed in claim 13, wherein said basic structural unit is arranged with m * n matrix kenel, and wherein m and n are respectively the positive integer more than or equal to 2.
15. resonator as claimed in claim 1, wherein said resonance body are circular or annular.
16. resonator as claimed in claim 1, wherein said resonance body is a square or rectangular.
17. resonator as claimed in claim 1, wherein said resonance body and said periodic structure comprise same material.
18. resonator as claimed in claim 17, the structure that wherein said resonance body and said periodic structure are one of the forming.
19. resonator as claimed in claim 1 also comprises at least one brace summer, the one of which end links said resonance body, and the other end links said periodic structure.
20. resonator as claimed in claim 19, wherein said resonance body, said brace summer and said periodic structure comprise same material.
21. resonator as claimed in claim 20, wherein said resonance body, said brace summer and said periodic structure are for being integrated into the structure of the single brace summer with fault of construction.
22. resonator as claimed in claim 1, it comprises two groups of periodic structures, and they link with the two ends of said resonance body respectively.
23. resonator as claimed in claim 22, wherein said two groups of periodic structures have symmetrical structure.
24. resonator as claimed in claim 1 also comprises the strong point, it is arranged at the other end below of said periodic structure and is positioned on the base material, makes said resonance body, said periodic structure formation one distance all and between the said base material.
25. resonator as claimed in claim 1, basic structural unit has a plurality of holes described in the wherein said periodic structure, and these holes are filled with and the different material of said basic structural unit material.
26. resonator as claimed in claim 25, wherein said hole is filled air.
27. resonator as claimed in claim 25, wherein said basic structural unit material comprises silicon, and described hole is filled tungsten.
28. a periodic structure is used micro electronmechanical manufacture process manufacturing, said structure comprises:
The periodic structure body of an one dimension; It is made up of basic structural unit at least; This basic structural unit is taken from and is had the periodically platy structure of hole of two-dimensional crystal lattice; Said basic structural unit in one dimension direction repeated arrangement to form said one dimension periodic structure body; To be four orthogonal geometry lines of cut have a shape that two-dimensional crystal lattice is periodically surrounded out on the platy structure of hole in said to the acquisition mode of wherein said basic structural unit; Said how much lines of cut are through the inside of said periodicity hole, and said basic structural unit has ditch or mute characteristic frequently frequently when periodic arrangement, make the elastic wave of importing into from said periodic structure one end can't be transmitted to the other end.
29. periodic structure as claimed in claim 28, wherein said basic structural unit is taken from the platy structure with two-dimension square lattice hole.
30. periodic structure as claimed in claim 28, wherein said basic structural unit is taken from the platy structure with two-dimentional triangular crystal lattice hole.
31. periodic structure as claimed in claim 28, wherein said basic structural unit is taken from the platy structure with two-dimentional hexagonal lattice hole.
32. periodic structure as claimed in claim 28, the described hole in the platy structure of wherein said tool two-dimensional crystal lattice periodicity hole is circular cross-section or elliptic cross-section or polygonal cross-section.
33. periodic structure as claimed in claim 28, the described hole in the platy structure of wherein said tool two-dimensional crystal lattice periodicity hole is filled with the material different with said platy structure.
34. periodic structure as claimed in claim 33, the described hole in the platy structure of wherein said tool two-dimensional crystal lattice periodicity hole is filled with air.
35. periodic structure as claimed in claim 33, wherein said tool the two-dimensional crystal lattice periodically described hole of the platy structure of hole are filled with tungsten.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US6628177B2 (en) * | 2000-08-24 | 2003-09-30 | The Regents Of The University Of Michigan | Micromechanical resonator device and micromechanical device utilizing same |
| US6710680B2 (en) * | 2001-12-20 | 2004-03-23 | Motorola, Inc. | Reduced size, low loss MEMS torsional hinges and MEMS resonators employing such hinges |
| JP2005104363A (en) * | 2003-09-30 | 2005-04-21 | Johnson Controls Automotive Systems Corp | Seat for vehicle |
| US7295088B2 (en) * | 2004-01-21 | 2007-11-13 | The Regents Of The University Of Michigan | High-Q micromechanical resonator devices and filters utilizing same |
| CN101103515A (en) * | 2005-01-07 | 2008-01-09 | 波士顿大学托管委员会 | Nanomechanical oscillator |
| WO2008100901A1 (en) * | 2007-02-12 | 2008-08-21 | Massachusetts Institute Of Technology | Transformative periodic structures, in particular tunable photonic crystals and phononic crystals |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6628177B2 (en) * | 2000-08-24 | 2003-09-30 | The Regents Of The University Of Michigan | Micromechanical resonator device and micromechanical device utilizing same |
| US6710680B2 (en) * | 2001-12-20 | 2004-03-23 | Motorola, Inc. | Reduced size, low loss MEMS torsional hinges and MEMS resonators employing such hinges |
| JP2005104363A (en) * | 2003-09-30 | 2005-04-21 | Johnson Controls Automotive Systems Corp | Seat for vehicle |
| US7295088B2 (en) * | 2004-01-21 | 2007-11-13 | The Regents Of The University Of Michigan | High-Q micromechanical resonator devices and filters utilizing same |
| CN101103515A (en) * | 2005-01-07 | 2008-01-09 | 波士顿大学托管委员会 | Nanomechanical oscillator |
| WO2008100901A1 (en) * | 2007-02-12 | 2008-08-21 | Massachusetts Institute Of Technology | Transformative periodic structures, in particular tunable photonic crystals and phononic crystals |
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