CN100539411C - Surface acoustic wave device - Google Patents
Surface acoustic wave device Download PDFInfo
- Publication number
- CN100539411C CN100539411C CNB2005800108867A CN200580010886A CN100539411C CN 100539411 C CN100539411 C CN 100539411C CN B2005800108867 A CNB2005800108867 A CN B2005800108867A CN 200580010886 A CN200580010886 A CN 200580010886A CN 100539411 C CN100539411 C CN 100539411C
- Authority
- CN
- China
- Prior art keywords
- acoustic wave
- surface acoustic
- piezoelectric substrate
- saw
- wave device
- 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 invention provides surface acoustic wave device.Adopt the surface acoustic wave device of quartz base plate to have the device size littler, and show high Q and excellent frequency-temperature characterisitic than conventional structure.On piezoelectric substrate (1), be equipped with by a plurality of interdigitation electrodes and refer to the interdigitation electrode (2) that constitutes, and the both sides of interdigitation electrode (2) be provided with grating reflector (3a, 3b).Piezoelectric substrate (1) is following quartzy flat board: wherein, the cutting angle θ that rotary Y cutting cuts quartz base plate is set in the scope of in the counterclockwise direction-64.0 ° of Z crystallographic axis＜θ＜-49.3 °, the direction of propagation of surface acoustic wave is set to become 90 ° ± 5 ° with respect to the X crystallographic axis, and the sound wave of being excited is the SH ripple.Interdigitation electrode (2) and reflector (3a, 3b) by Al or the alloy that mainly comprises Al constitute, be under the situation of wavelength of surface acoustic wave at λ, be set in the scope of 0.04＜H/ λ＜0.12 by the electrode film thickness H/ λ of standard of wavelengthization.
Description
Technical field
The present invention relates to use the surface acoustic wave device of quartz base plate, wherein reduced device size, increased the Q value and improved frequency-temperature characterisitic.
Background technology
In recent years, surface acoustic wave (after this being called SAW) device has been widely used as the parts of mobile communication terminal, vehicle-mounted equipment etc., is starved of its miniaturization, has high Q value and has excellent frequency stability.
As the SAW device of realizing that these need, exist the SAW device that uses ST cutting quartz base plate.ST cutting quartz base plate is the cutting title with quartz plate of face by in the counterclockwise direction the XZ face being obtained from 42.75 ° of angles of Z crystallographic axis rotation as rotating shaft with the X crystallographic axis (XZ ' face), and this ST cutting quartz base plate uses as the SAW (after this be called ST and cut quartzy SAW) along (P+SV) ripple (being called " R wave ") of X crystalline axis direction propagation.ST cutting quartz saw device is widely used in the filter of the SAW resonator as oscillator, the RF section that is arranged on mobile communication terminal and the use of the IF between the IC etc.
ST cutting quartz saw device can realize that the reason of the miniature device of high Q value comprises the reflection this point that can effectively utilize SAW.ST shown in Figure 13 cuts quartzy SAW resonator as an example with explanation.The interdigitation electrode (after this being called IDT) 102 that a plurality of electrodes that ST cuts quartzy SAW syntonizer to be had following structure: ST cutting quartz base plate 101 to be provided with to have interfix refer to, and be provided with grating reflector 103a and the 103b that is used to reflect SAW in the both sides of IDT 102.Because it is the ripple of propagating along the surface of piezoelectric substrate that ST cuts quartzy SAW, thus its by grating reflector 103a and 103b usable reflection, the SAW energy can be limited among the IDT 102 fully, thereby the miniature device that can obtain to have high Q value.
Using a key factor of SAW device is frequency-temperature characterisitic.Cut among the quartzy SAW at ST, as everyone knows, a temperature coefficient of frequency-temperature characterisitic of SAW is zero, represent its characteristic by conic section, and, because significantly reduced the frequency wave momentum, so SAW has excellent frequency stability by making point of inflection temperature (turnovertemperature) be positioned at the adjustment at serviceability temperature scope center.
Yet in ST cutting quartz saw device, though a temperature coefficient is zero, the secondary temperature coefficient is relatively large, for example-0.034 (ppm/ ℃
2).Therefore, when the serviceability temperature expanded range, the frequency fluctuation quantitative change gets greatly.
A kind of method as head it off, " Surface SkimmingBulk Wave " at Meirion Lewis, IEEE Ultrasonics Symp.Proc. discloses a kind of SAW device in pp.744 to 752 (1977) and Japanese Patent Publication 62-016050 number.As shown in figure 14, this SAW device be characterised in that cutting angle θ that rotary Y cutting cuts quartz base plate be set at rotate the position at-50 ° of angles in the counterclockwise direction from the Z crystallographic axis near, and the direction of propagation of SAW is set at the direction vertical with the X crystallographic axis (Z ' direction of principal axis).In addition, when representing cutting angle with Eulerian angles, obtain (0 °, θ+90 °, 90 °)=(0 °, 40 °, 90 °).This SAW device is characterised in that the SH ripple of just propagating in the piezoelectric substrate lower face by the IDT excitation, and oscillation energy just is limited in the electrode below.The frequency of this SAW device-temperature characterisitic forms cubic curve, owing to the frequency wave momentum in the serviceability temperature scope significantly reduces, so obtain excellent frequency-temperature characterisitic.
Yet, because the SH ripple is the ripple that subduction is basically internally advanced at substrate, so the reflection efficiency to SAW that obtains by grating reflector is lower than the reflection efficiency that the ST that propagates along the piezoelectric substrate surface cuts quartzy SAW.Therefore, there is the problem be difficult to realize have the small-sized SAW device of high Q.Because formerly communique comprises about as the disclosing of the delay line that does not utilize the SAW reflection, but it does not propose to utilize any means of SAW reflection, so think that it is difficult to the SAW device is dropped into practical application.
In order to address the above problem, Japan discloses so-called many to IDT type SAW resonator special fair 01-034411 number, wherein, as shown in figure 15, the cutting angle θ that rotary Y cutting cuts quartz base plate be set at-50 ° near, and the direction of propagation of SAW is set to be formed with on the piezoelectric substrate 111 of the direction vertical with the X crystallographic axis (Z ' direction of principal axis) many to (for example 800 ± 200 couples) IDT 112 therein, thus, need not to utilize grating reflector and only the reflections by IDT 112 itself limit the SAW energy, thereby realize high Q.
Yet, compare with the SAW resonator that comprises grating reflector, manyly can not obtain energy limited effect efficiently to IDT type SAW resonator.Be increased to 800 ± 200 pairs greatly owing to obtain the right quantity of the needed IDT of high Q value, cut the big problem of quartzy SAW resonator so exist device size to become than ST, thereby can't satisfy the demand that in recent years size is reduced.
In the special fair 01-034411 of Japan number in the disclosed SAW resonator, in the time will being shown λ by the wavelength table of the SAW of IDT excitation, can by electrode film thickness be set to 2% λ or bigger, be preferably 4% λ or the littler Q of increase value.Yet when resonance frequency was 200MHz, the Q value reached saturated near 4% λ, but that the Q value that obtains this moment becomes is only about 20000, cut quartzy SAW resonator with ST and compared, and only can obtain to cut Q value Q value about equally in the quartzy SAW resonator with ST.Owing to this reason, think since when film thickness more than 2% λ in the scope below 4% λ the time SAW can not fully concentrate on the piezoelectric substrate surface, so can not effectively utilize reflection.
[patent documentation 1] Japanese Patent Publication 62-016050 number
[patent documentation 2] Japan special fair 01-034411 number
[non-patent literature 1] Meirion Lewis, " Surface Skimming Bulk Wave, SSBW ", IEEE Ultrasonics Symp.Proc., pp.744 to 752 (1977)
Summary of the invention
The problem to be solved in the present invention
Have problem to be solved as follows: when using ST cutting quartz base plate as piezoelectric substrate, the secondary temperature coefficient of frequency-temperature characterisitic is-0.034 (ppm/ ℃
2) big, make the frequency wave momentum in fact become quite big.The structure of disclosed SAW device comprises following problem in Japanese special fair 01-034411 number: owing to have to be provided with the logarithm of IDT quite big, device size increases.
The device that addresses the above problem
In order to address the above problem, the described invention of claim 1 according to the present invention provides a kind of SAW device, this SAW device comprises piezoelectric substrate and is formed on the described piezoelectric substrate and by Al or comprise the IDT that Al makes as the alloy of main component, excited wave is the SH ripple, described SAW device is characterised in that, described piezoelectric substrate is the rotary Y cutting cutting board of being made by quartzy flat board, the cutting angle θ of wherein said piezoelectric substrate is the anglec of rotation of Z crystallographic axis when described piezoelectric substrate rotates around the X crystallographic axis, the direction that described piezoelectric substrate forwards positive Y-axis side to from positive Z sidespin is that described cutting angle θ is negative direction, and described cutting angle θ is set in the scope of-64.0 °＜θ＜-49.3 °, and it is 90 ° ± 5 ° that the direction of propagation of SAW is set to respect to the X crystallographic axis, and, when will being excited the wavelength of SAW when being represented as λ, be set to satisfy 0.04＜H/ λ＜0.12 by the electrode film thickness H/ λ of the standard of wavelengthization of IDT.
According to claim 2ly the invention provides described SAW device, it is characterized in that the relation between cutting angle θ and the electrode film thickness H/ λ satisfies :-1.34082 * 10
-4* θ
3-2.34969 * 10
-2* θ
2-1.37506 * θ-26.7895＜H/ λ＜-1.02586 * 10
-4* θ
3-1.73238 * 10
-2* θ
2-0.977607 * θ-18.3420.
According to claim 3ly the invention provides described SAW device, it is characterized in that, when being defined as line degree of metalization mr, the relation between the product H/ λ * mr of cutting angle θ and electrode film thickness and line degree of metalization satisfies :-8.04489 * 10 when electrode finger widths that the electrode that will constitute IDT refers to/(electrode finger widths+electrode refer between interval)
-5* θ
3-1.40981 * 10
-2* θ
2-0.825038 * θ-16.0737＜H/ λ * mr＜-6.15517 * 10
-5* θ
3-1.03943 * 10
-2* θ
2-0.586564 * θ-11.0052.
According to claim 4ly the invention provides a kind of SAW device, this SAW device comprises piezoelectric substrate and is formed on the described piezoelectric substrate and by Al or comprise the IDT that Al makes as the alloy of main component, utilize excited wave to be the SH ripple, described SAW device is characterised in that, described piezoelectric substrate is the rotary Y cutting cutting board of being made by quartzy flat board, the cutting angle θ of wherein said piezoelectric substrate is the anglec of rotation of Z crystallographic axis when described piezoelectric substrate rotates around the X crystallographic axis, the direction that described piezoelectric substrate forwards positive Y-axis side to from positive Z sidespin is that described cutting angle θ is negative direction, and described cutting angle θ is set in the scope of-61.4 °＜θ＜-51.1 °, and it is 90 ° ± 5 ° that the direction of propagation of SAW is set to respect to the X crystallographic axis, and, when will being excited the wavelength table of SAW when being shown λ, be set to satisfy 0.05＜H/ λ＜0.10 by the electrode film thickness H/ λ of the standard of wavelengthization of IDT.
According to claim 5ly the invention provides described SAW device, it is characterized in that the relation between cutting angle θ and the electrode film thickness H/ λ satisfies :-1.44605 * 10
-4* θ
3-2.50690 * 10
-2* θ
2-1.45086 * θ-27.9464＜H/ λ＜-9.87591 * 10
-5* θ
3-1.70304 * 10
-2* θ
2-0.981173 * θ-18.7946.
According to claim 6ly the invention provides described SAW device, it is characterized in that, when being defined as line degree of metalization mr, the relation between the product H/ λ * mr of cutting angle θ and electrode film thickness and line degree of metalization satisfies :-8.67632 * 10 when electrode finger widths that the electrode that will constitute IDT refers to/(electrode finger widths+electrode refer between interval)
-5* θ
3-1.50414 * 10
-2* θ
2-0.870514 * θ-16.7678＜H/ λ * mr＜-5.92554 * 10
-5* θ
3-1.02183 * 10
-2* θ
2-0.588704 * θ-11.2768.
The invention provides described SAW device according to claim 7 to 14 is described, it is characterized in that the SAW device is any in the following device: a port SAW resonator, two port SAW resonators, lateral type multi-mode filter, longitudinally coupled multi-mode filter, trapezoidal SAW filter, wherein be provided with or propagate horizontal SAW filter or the SAW transducer of the IDT of SAW along a direction along twocouese.
According to claim 15ly the invention provides described SAW device, it is characterized in that the SAW device has grating reflector on the IDT both sides.
Module device or the oscillating circuit that the invention provides use according to each the described SAW device in the claim 1 to 15 according to claim 16.
The invention effect
Have following structure according to claim 1 of the present invention or 4 described SAW devices: use cutting angle θ in-64.0 °＜θ＜-49.3 °, the rotary Y cutting that is preferably in the scope of-61.4 °＜θ＜-51.1 ° cuts quartz base plate, use is excited for making that the direction of propagation of SAW is the SH ripple of (90 ° ± 5 °) with respect to the X crystallographic axis, the electrode material that is used for IDT and grating reflector is Al or the alloy that mainly comprises Al, come standardized electrode film thickness H/ λ to be set to satisfy 0.04＜H/ λ＜0.12 by wavelength, be preferably 0.05＜H/ λ＜0.10.Because the present invention is constituted as the ripple that the script subduction is advanced and concentrates on the substrate surface so that grating reflector etc. can effectively utilize the reflection of SAW in substrate, compare the SAW device that has reduced size, had high Q value and frequency stability excellence so can provide with ST cutting quartz saw device.
By satisfying the condition of claim 2 or 5 described electrode film thickness H/ λ and cutting angle θ, can with point of inflection temperature Tp (℃) be arranged in the actual temperature scope.
Product H/ λ * mr by satisfying claim 3 or 6 described electrode film thicknesses and line degree of metalization and the condition of cutting angle θ, can with point of inflection temperature Tp (℃) be arranged in the actual temperature scope.
By using the SAW device of each the described various systems in the claim 7 to 14, can provide the SAW device that has reduced size, had high Q value and frequency stability excellence.
Since the SAW device described in the claim 15 by on the both sides of IDT, grating reflector being set fully with the energy limited of SAW in IDT, so the small-sized SAW device with high Q value can be provided.
Because described module device of claim 16 or oscillating circuit use according to SAW device of the present invention, so small-sized and high performance module device or oscillating circuit can be provided.
Description of drawings
Fig. 1 is the figure that is used to illustrate according to SAW resonator of the present invention, and wherein Fig. 1 (a) is the plane graph of IDT, and Fig. 1 (b) is the profile of IDT.
Fig. 2 illustrates according to the comparison between SAW resonator of the present invention and the conventional products, and wherein Fig. 2 (a) is the figure that illustrates about the comparison of Q value, quality factor and secondary temperature coefficient, and Fig. 2 (b) is the figure that illustrates about the comparison of frequency-temperature characterisitic.
Fig. 3 is the figure that illustrates according to electrode film thickness H/ λ in the SAW resonator of the present invention and the relation between the Q value.
Fig. 4 is the figure that illustrates according to electrode film thickness H/ λ in the SAW resonator of the present invention and the relation between the secondary temperature coefficient.
Fig. 5 (a) is the figure that illustrates according to electrode film thickness H/ λ in the SAW resonator of the present invention and the relation between the point of inflection temperature Tp, 5 (b) be illustrate wherein cutting angle θ and the figure of the relation between the point of inflection temperature Tp.
Fig. 6 be illustrate when according to the point of inflection temperature Tp in the SAW resonator of the present invention (℃) satisfy Tp=-50,0 ,+70, and+the cutting angle θ that obtained in 125 o'clock and the figure of the relation between the electrode film thickness H/ λ.
Fig. 7 illustrates according to the product H/ λ * mr of electrode film thickness in the SAW resonator of the present invention and line degree of metalization and the figure of the relation between the point of inflection temperature Tp.
Fig. 8 be illustrate when according to the point of inflection temperature Tp in the SAW resonator of the present invention (℃) satisfy Tp=-50,0 ,+70, and+125 o'clock, the figure of the relation between the product H/ λ * mr of cutting angle θ and electrode film thickness and line degree of metalization.
Fig. 9 is the figure that is used to illustrate according to two-port SAW resonator of the present invention.
Figure 10 is the figure that is used to illustrate according to DMS filter of the present invention, and wherein Figure 10 (a) is the figure that lateral type DMS filter is shown, and Figure 10 (b) is the figure that longitudinally coupled DMS filter is shown.
Figure 11 is the figure that is used to illustrate according to trapezoidal SAW filter of the present invention.
Figure 12 is the figure that is used to illustrate according to horizontal SAW filter of the present invention, wherein Figure 12 (a) illustrates the figure that is provided with along the horizontal SAW filter of the IDT of both direction excitation SAW, and Figure 12 (b) illustrates the figure that is provided with along the horizontal SAW filter of the IDT of a direction excitation SAW.
Figure 13 is used to illustrate that conventional ST cuts the figure of quartzy SAW resonator.
Figure 14 (a) and 14 (b) are used to illustrate that-50 ° of rotary Y cuttings cut the figure that 90 ° of X propagate quartz base plate.
Figure 15 is used to illustrate conventional many figure to IDT type SAW resonator.
Description of reference numerals
1 piezoelectric substrate
2?IDT
3a, 3b grating reflector
4a, 4b i/o pads
5a, 5b plain conductor
6 encapsulation
31 piezoelectric substrates
32、33?IDT
34a, 34b grating reflector
41 piezoelectric substrates
42 SAW resonators
51 piezoelectric substrates
52?IDT
61 piezoelectric substrates
62 1 port SAW resonators
71 piezoelectric substrates
72 input IDT
73 output IDT
74 bucking electrodes
75 sound-absorbing materials
82,83 single phase unidirectional transducers
Embodiment
To describe the present invention in detail based on embodiment shown in the drawings below.Fig. 1 (a) is the plane graph according to SAW resonator of the present invention, and wherein piezoelectric substrate 1 is provided with grating reflector 3a and the 3b that SAW is reflected of being used for that the positive electrode with interfix refers to the IDT 2 that refers to negative electrode and is positioned at IDT 2 both sides.The input pad 4a/ o pads 4b of IDT 2 is electrically connected to each other by plain conductor 5a and 5b with encapsulation 6 input/output terminal, will encapsulate 6 opening portion by lid and seal airtightly.As shown in figure 14, piezoelectric substrate 1 is following quartzy dull and stereotyped: wherein the rotary Y cutting cutting angle θ that cuts quartz base plate is set at and rotates near the position at-50 ° of angles in the counterclockwise direction and the direction of propagation of SAW is set to direction (90 ° ± 5 °) with X crystallographic axis approximate vertical from the Z crystallographic axis, and the SAW that is excited is the SH ripple.The electrode material that is used for IDT 2 and grating reflector 3a and 3b is Al or comprises the alloy of Al as main component.Fig. 1 (b) illustrates the section of IDT 2, when the wavelength table of the SAW that will encourage on IDT 2 in the present embodiment is shown λ, electrode film thickness is expressed as value H/ λ by standard of wavelengthization, and when electrode finger widths L/ that the electrode that will constitute IDT 2 refers to (electrode finger widths L+ electrode refer between interval S) when being defined as line degree of metalization mr, satisfies mr=0.60.
In the present invention, consider the defective in the routine techniques, by electrode film thickness H/ λ being provided with greater than the electrode film thickness of routine, thereby SAW is concentrated on the piezoelectric substrate surface, make and effectively to utilize the reflection of grating reflector SAW, and, even the quantity that reduces IDT logarithm or grating reflector also can be with the SAW energy limited in IDT, thus reduction of device size.
Usually, in the optimal design to the SAW resonator, frequency-excellent in temperature characteristic, Q value height and Capacity Ratio (capacitance ratio) γ little (being that quality factor (Q/ γ) are big) are very important.At the various characteristics of this investigation according to SAW resonator of the present invention.Fig. 2 has described the various characteristics at the resonator that obtains under the following situation: in SAW resonator shown in Figure 1, use-51 ° of rotary Y cuttings to cut 90 ° of X and propagate quartz base plates (being expressed as (0 °, 39 °, 90 °) with Eulerian angles) as piezoelectric substrate 1; Resonance frequency is set to 315MHz; Electrode film thickness H/ λ is set to 0.06; The logarithm of IDT 2 is 100; And the quantity of grating reflector 3a and 3b each naturally 100.Shown in Fig. 2 (a) according to Q value, quality factor and the secondary temperature coefficient of actual trial result, shown in Fig. 2 (b) based on this frequency-temperature characterisitic.In order to compare, also show the size of piezoelectric substrate and the various characteristics that cuts quartzy SAW resonator according to the measure-alike ST of the piezoelectric substrate of SAW resonator of the present invention, as the various characteristics in the conventional products.
With reference to Fig. 2, in the time will cutting quartzy SAW resonator and be compared to each other according to SAW resonator of the present invention and conventional ST, obtain following big value: the former Q value is 1.8 times of the latter or more, and the former quality factor are about twices of the latter.About frequency-temperature characterisitic, in SAW resonator according to the present invention, can confirm very excellent effect: can obtain approximately+25 ℃ point of inflection temperature Tp, and because the frequency wave momentum of temperature reduces to about 0.6 times of routine techniques.
SAW resonator according to the present invention can reduce the size of piezoelectric substrate, keeps cutting than ST the good Q value of Q value of quartzy SAW resonator simultaneously.This is to cut situation in the quartzy SAW resonator because the SAW volume reflection at IDT or grating reflector place according to the present invention is far longer than at ST with respect to the recruitment of the increase of the electrode film thickness H/ λ of SAW resonator.That is, can be by making electrode film thickness H/ λ very big according to SAW resonator of the present invention, cut IDT logarithm or the grating reflector quantity that IDT logarithm in the quartzy SAW resonator or grating reflector quantity lacks than ST and realize high Q value thereby use.
Fig. 3 illustrates according to electrode film thickness H/ λ in the SAW resonator of the present invention and the relation between the Q value, and wherein the resonator design condition is identical with above-mentioned condition.As can be seen from Figure 3, in the scope of 0.04＜H/ λ＜0.12, can obtain to surpass the value that ST cuts the Q value (=15000) of quartzy SAW resonator.In addition, can obtain to surpass 20000 high Q value by scope being arranged on 0.05＜H/ λ＜0.10.
Many Q values to IDT type SAW resonator shown in the special fair 01-034411 of Japan number and Q value according to SAW resonator of the present invention are compared, the Q value that obtains in described patent application is the value when resonance frequency is 207.561 (MHz), and when resonance frequency changes to the resonance frequency of using in the present embodiment 315 (MHz), the Q value approximately is 15000, is approximately equal to ST in this Q value and cuts Q value in the quartzy SAW resonator.In the comparison that the size of resonator is carried out, that describes in the described patent application is how right to 800 ± 200 IDT of IDT type SAW resonator needs, but the present invention only needs to hold 200 spaces that IDT is right for IDT and grating reflector, thereby the present invention can reduce size significantly.Therefore, in the scope by electrode film thickness being arranged on 0.04＜H/ λ＜0.12 and provide grating reflector to reflect SAW effectively, can realize with the special fair 01-034411 of Japan number in disclosedly many IDT type SAW resonator is compared the SAW device that size is littler and the Q value is higher.
Next, Fig. 4 illustrates according to electrode film thickness H/ λ in the SAW resonator of the present invention and the relation between the secondary temperature coefficient, and wherein the design condition of resonator is identical with above-mentioned condition.As can be seen from Figure 4, in the scope of 0.04＜H/ λ＜0.12 that can obtain high Q value, can obtain to cut (ppm/ ℃ of the secondary temperature coefficient-0.034 of quartzy SAW resonator than ST
2) better be worth.
Based on the above, by electrode film thickness H/ λ is arranged in the scope of 0.04＜H/ λ＜0.12, can provide that compare size with disclosed SAW device in ST cutting quartz saw device and Japanese special fair 01-034411 number littler and the Q value is higher and the SAW device of frequency stability excellence.
Be set to-51 ° situation though above only described cutting angle θ, even but cutting angle θ changes in SAW resonator according to the present invention, the film thickness dependence can great changes have taken place yet, thus, by electrode film thickness being arranged in the scope of 0.04＜H/ λ＜0.12, even cutting angle has been offset the several years from-51 °, also can obtain the secondary temperature coefficient of excellent Q value and excellence.
SAW resonator according to the present invention presents temperature characterisitic three times in very wide temperature range, but temperature characterisitic can be considered as quadratic behavior in specific narrow temperature scope, the point of inflection temperature Tp in this temperature range is according to electrode film thickness and cutting angle and change.Therefore, no matter how excellent frequency-temperature characterisitic is, and in the time of outside point of inflection temperature Tp fluctuates the serviceability temperature scope, frequency stability is deterioration significantly all.In order to be implemented in the excellent frequency stability in (50 ℃ to+125 ℃) in the actual serviceability temperature scope, not only must The effect secondary temperature coefficient but also necessary The effect point of inflection temperature Tp.
Fig. 5 (a) is illustrated in according to electrode film thickness H/ λ that obtains when cutting angle θ is set to-50.5 ° in the SAW resonator of the present invention and the relation between the point of inflection temperature Tp.Obvious from Fig. 5 (a), when electrode film thickness H/ λ becomes big, point of inflection temperature Tp step-down, and the relation between electrode film thickness H/ λ and the point of inflection temperature Tp can be represented by following approximate expression.
Tp(H/λ)＝-41825×(H/λ)
2+2855.4×(H/λ)-26.42 …(1)
Except its section, this approximate expression (1) can be applied near the cutting angle-50 °.
Fig. 5 (b) is illustrated in according to cutting angle θ that obtains when film thickness H/ λ is set to 0.06 in the SAW resonator of the present invention and the relation between the point of inflection temperature Tp.Obvious from Fig. 5 (b), when the absolute value of cutting angle θ reduced, point of inflection temperature Tp reduced, and the relation between cutting angle θ and the point of inflection temperature Tp can be represented by following approximate expression.
Tp(θ)＝-43.5372×θ-2197.14 …(2)
Subsequently, from formula (1) and formula (2) as can be known, when electrode film thickness H/ λ is set to satisfy 0.04＜H/ λ＜0.12, for point of inflection temperature Tp being arranged on (50 ℃ to+125 ℃) in the actual serviceability temperature scope, cutting angle θ is arranged in the scope of-59.9 °≤θ≤-48.9 ° just enough.
When considering electrode film thickness H/ λ and cutting angle θ, point of inflection temperature Tp is represented by the following approximate expression of utilizing formula (1) and formula (2).
Tp(H/λ，θ)＝Tp(H/λ)+Tp(θ)＝-41825×(H/λ)
2+2855.4×(H/λ)-43.5372×θ-2223.56 …(3)
For point of inflection temperature Tp being arranged on (50 ℃ to+125 ℃) in the serviceability temperature scope, electrode film thickness H/ λ and cutting angle θ can be arranged on by in the represented scope of the following formula that obtains from approximate expression (3).
0.9613≤-18.498×(H/λ)
2+1.2629×(H/λ)-0.019255×θ≤1.0387 …(4)
Therefore, in the present invention, use the rotary Y cutting of cutting angle θ in the scope of-59.9 °≤θ≤-48.9 ° to cut quartz base plate, use is excited for making that the direction of propagation of SAW is the SH ripple approximately perpendicular to the direction of X-axis, the electrode material that is used for IDT and grating reflector is Al or comprises the alloy of Al as main component, and electrode film thickness H/ λ is set to satisfy 0.04＜H/ λ＜0.12.Utilize this structure, can realize littler and the Q value is higher and the SAW device of frequency stability excellence than ST cutting quartz saw device size.
To investigate optimal conditions at this.As shown in Figure 3, preferably, with electrode film thickness H/ λ be arranged on can obtain 20000 or the scope of 0.05＜H/ λ＜0.10 of higher Q value in.In addition, preferably, cutting angle θ is arranged in the scope of-55.7 °≤θ≤-50.2 °, point of inflection temperature Tp is arranged on (0 ℃ to+70 ℃) in the actual temperature limit.In addition, preferably, cutting angle θ and electrode film thickness H/ λ are arranged on by in the following formula restricted portion that obtains from approximate expression (3).
0.9845≤-18.518×(H/λ)
2+1.2643×(H/λ)-0.019277×θ≤1.0155 …(5)
In the above description, according to the electrode film thickness H/ λ that when the cutting angle θ shown in Fig. 5 (a) is set to-50.5 °, obtains and the relation between the point of inflection temperature Tp and the cutting angle θ of acquisition when the electrode film thickness H/ λ shown in Fig. 5 (b) is set to 0.06 and the relation between the point of inflection temperature Tp, derived situation lower electrode film thickness H/ λ in point of inflection temperature Tp falls into actual serviceability temperature scope and the relational expression between the cutting angle θ.Find out condition more specifically by the experiment of carrying out by the expanded scope of cutting angle θ, will describe them below.
Fig. 6 illustrate point of inflection temperature Tp in the SAW resonator (℃) satisfy Tp=-50,0 ,+70 and+the cutting angle θ of the quartz base plate that obtained in 125 o'clock and the relation between the electrode film thickness H/ λ, wherein the approximate expression of each Tp characteristic is as follows:
From Fig. 6 as seen, for with point of inflection temperature Tp (℃) be set to satisfy as actual range-50≤Tp≤+ 125, can cutting angle θ and electrode film thickness H/ λ be set to satisfy curve area surrounded by Tp=-50 ℃ and Tp=+125 ℃, promptly-1.34082 * 10
-4* θ
3-2.34969 * 10
-2* θ
2-1.37506 * θ-26.7895＜H/ λ＜-1.02586 * 10
-4* θ
3-1.73238 * 10
-2* θ
2-0.977607 * θ-18.3420.This moment must electrode film thickness H/ λ scope be set to satisfy 0.04＜H/ λ＜0.12 of the characteristic that makes characteristic can be better than conventional ST cutting quartz and the scope of cutting angle θ is set to satisfy-64.0＜θ＜-49.3 corresponding with scope from point A to point B shown in Figure 6.
In addition, in investigation about optimal conditions more, preferably, with point of inflection temperature Tp (℃) be set to satisfy 0≤Tp≤+ 70 corresponding with actual serviceability temperature scope.For with Tp (℃) be arranged in the above-mentioned scope, can cutting angle θ and electrode film thickness H/ λ be set to satisfy curve Tp=0 shown in Figure 6 ℃ and Tp=+70 ℃ of area surrounded, promptly-1.44605 * 10
-4* θ
3-2.50690 * 10
-2* θ
2-1.45086 * θ-27.9464＜H/ λ＜-9.87591 * 10
-5* θ
3-1.70304 * 10
-2* θ
2-0.981173 * θ-18.7946.In addition, preferably, electrode film thickness H/ λ is set to satisfy and can obtains 20000 or the scope of 0.05＜H/ λ＜0.10 of higher Q value.In addition, for electrode film thickness is arranged in the above-mentioned scope and with point of inflection temperature Tp (℃) be set in the scope of 0≤Tp≤+ 70, must cutting angle θ be set to satisfy with from-61.4＜θ＜-51.1 corresponding shown in Fig. 6 (a) from a C to the scope of a D.
According to above-mentioned The effect, have been found that, by using cutting angle θ to satisfy-64.0 °＜θ＜-49.3 °, the rotary Y cutting that is preferably-61.4 °＜θ＜-51.1 ° cuts quartz base plate, use is excited for making the direction of propagation of SAW be the SH ripple approximately perpendicular to the direction of X-axis, by Al or the alloy that mainly comprises Al be formed for the electrode material of IDT or grating reflector, and electrode film thickness H/ λ is set to satisfy 0.04＜H/ λ＜0.12, be preferably 0.05＜H/ λ＜0.10, can obtain the excellent temperature characterisitic of Q value, and point of inflection temperature Tp can be arranged in the actual serviceability temperature scope greater than the Q value of ST cutting quartz saw device.
Be fixed as 0.60 example though line degree of metalization mr with IDT above has been described, hereinafter will investigate the example of the Tp characteristic that when the line degree of metalization is included in the variable, obtains.
Fig. 7 illustrates the product H/ λ * mr of electrode film thickness and line degree of metalization and the relation between the point of inflection temperature Tp.Vertical axis represent point of inflection temperature Tp (℃), and trunnion axis is represented the product H/ λ * mr of electrode film thickness and line degree of metalization.At this moment, the cutting angle θ of quartz base plate is set to-51.5 °.As shown in Figure 7, point of inflection temperature Tp reduces along with the increase of the value of the product H/ λ * mr of electrode film thickness and line degree of metalization as can be known.
Next, Fig. 8 illustrate when point of inflection temperature Tp (℃) be-50,0 ,+70 and+relation between the quartz base plate cutting angle θ that obtained in 125 o'clock and the product H/ λ * mr of electrode film thickness and line degree of metalization.The approximate expression of each Tp characteristic is as follows:
From Fig. 8 as seen, for with point of inflection temperature Tp (℃) be set to satisfy as actual range-50≤Tp≤+ 125, can cutting angle θ and the product H/ λ * mr of electrode film thickness and line degree of metalization be set to satisfy by curve Tp=-50 ℃ and Tp=+125 ℃ of area surrounded, promptly-8.04489 * 10
-5* θ
3-1.40981 * 10
-2* θ
2-0.825038 * θ-16.0737＜H/ λ * mr＜-6.15517 * 10
-5* θ
3-1.03943 * 10
-2* θ
2-0.586564 * θ-11.0052.At this moment, scope that must electrode film thickness H/ λ is set to obtain 0.04＜H/ λ＜0.12 of the characteristic better than the characteristic in the conventional ST cutting quartz, and the scope of cutting angle θ is set to-64.0＜θ＜-49.3.
For with point of inflection temperature Tp (℃) be set to satisfy 0≤Tp≤+ 70 as actual serviceability temperature scope, can cutting angle θ and the product H/ λ * mr of electrode film thickness and line degree of metalization be set to satisfy by curve Tp=0 shown in Figure 8 ℃ and Tp=+70 ℃ of area surrounded, promptly-8.67632 * 10
-5* θ
3-1.50414 * 10
-2* θ
2-0.870514 * θ-16.7678＜H/ λ * mr＜-5.92554 * 10
-5* θ
3-1.02183 * 10
-2* θ
2-0.588704 * θ-11.2768.At this moment, preferably electrode film thickness H/ λ is set to satisfy and can obtains 20000 or 0.05＜H/ λ＜0.10 of higher Q value, and, for electrode film thickness be set to above-mentioned scope and with point of inflection temperature Tp (℃) be arranged in the scope of 0≤Tp≤+ 70, preferably cutting angle θ is set to satisfy-61.4＜θ＜-51.1.
Though only described a port SAW resonator as illustrated in fig. 1 so far, it not is other SAW devices of a port SAW resonator that the present invention can be applied to.The structure of various SAW devices will be described below.
Fig. 9 illustrates following two-port SAW resonator: wherein, be provided with along the direction of propagation of SAW on the piezoelectric substrate 31 IDT 32 and 33 and the both sides of IDT 32 and 33 be provided with grating reflector 34a and 34b, in this two-port SAW resonator, also can as a port SAW resonator, realize high Q value.
Figure 10 illustrates bimodulus SAW (DMS) filter that utilizes the acoustical coupling of a SAW resonator system as resonator filter, wherein Figure 10 (a) illustrates the lateral type DMS filter that wherein is provided with SAW resonator 42 on piezoelectric substrate 41 with the direction of propagation abreast adjacent to each other, and Figure 10 (b) illustrates the longitudinally coupled DMS filter of two-port that wherein is provided with the SAW resonator that comprises IDT 52 on piezoelectric substrate 51 along the direction of propagation of SAW.Described lateral type DMS filter utilizes the acoustical coupling vertical with the direction of propagation, and the longitudinally coupled DMS filter of two-port utilizes and the acoustical coupling of direction of propagation level.These DMS filters have can obtain smooth passband and the excellent frequency band characteristic of degree of inhibition outward.The longitudinally coupled DMS filter of two-port can be connected with the SAW resonator so that near the frequency band the passband is carried out the altitude decay.The present invention can be applied to utilize the multimode SAW filter of high-rder mode, perhaps is applied to all carry out on the direction of direction vertical with the direction of propagation and level the multimode SAW filter of acoustical coupling.
Figure 11 illustrates by by trapezoidal shape (being made of series, parallel and series connection) the ladder type SAW filter that a plurality of port SAW resonators 62 constitute is set on piezoelectric substrate 61, as another system of resonator filter.Described ladder type SAW filter can obtain near the decay gradient of passband than near the more precipitous filter characteristic of decay gradient the passband in the DMS filter.
Figure 12 illustrates horizontal SAW filter, and wherein Figure 12 (a) is illustrated in a horizontal SAW filter that is provided with input IDT 72 and output IDT 73 on the piezoelectric substrate 71 along the direction of propagation of SAW by predetermined space.IDT 72 and 73 with SAW along two-way propagation.Can provide bucking electrode 74 to prevent the influence of the direct wave between input terminal and the lead-out terminal, perhaps can on the two ends of piezoelectric substrate 71, apply sound-absorbing material 75 to suppress unnecessary reflected wave from base board end surface.Because can design the amplitude response of horizontal SAW filter and phase characteristic and its frequency band degree of inhibition height outward independently of one another, thus laterally the SAW filter through being commonly used for the IF filter.
Laterally the SAW filter has following problem: owing to SAW equally propagates to the right and left along the direction of propagation, so the insertion loss of filter becomes very big.As being used for solution to the problems described above, shown in Figure 12 (b), there is the horizontal SAW filter that is provided with so-called single phase unidirectional transducer (SPUDT) 82 and 83, in SPUDT 82 and 83, electrode refers to arrange or the electrode finger widths comes excitation and the reflection of SAW are weighted by changing, thus the unidirectional excitation of carrying out SAW.Because the unidirectional excitation of carrying out SAW is so can obtain the low loss filter characteristic.As other structure, existence wherein is provided with the horizontal SAW filter of what is called reflection group (reflection bank) type of grating reflector etc. between the active electrode of IDT.
In above-mentioned various SAW devices, clearly, following quartzy dull and stereotyped by using: the scope that is set to satisfy from the Z crystallographic axis in the counterclockwise direction in-64.0 °＜θ＜-49.3 ° of the rotary Y cutting cutting angle θ that cuts quartz base plate wherein as piezoelectric substrate, be preferably the scope of-61.4 °＜θ＜-51.1 °, and the direction of propagation of surface acoustic wave is set to become 90 ° ± 5 ° with respect to the X crystallographic axis, and electrode film thickness H/ λ is set to satisfy the scope of 0.04＜H/ λ＜0.12, be preferably the scope that satisfies 0.05＜H/ λ＜0.10, can obtain to the present invention in the similar advantage of advantage that obtained.
In above-mentioned SAW device, clearly, even on IDT or grating reflector, be formed with diaphragm (for example, by SiO
2Deng the diaphragm of making, by by Al being carried out diaphragm that anodic oxidation obtains etc.) or on the top of Al electrode or bottom, be formed with close adhesion layer or other metallic films that is used to improve electric durability, also can obtain to the present invention in the similar advantage of advantage that obtained.Self-evident, SAW device according to the present invention can be applied to sensor component or module device, oscillating circuit etc.Owing to can reduce Capacity Ratio γ by use SAW device according to the present invention in voltage control SAW oscillator (VCSO) etc., so can adopt wideer frequency range.
Except as shown in Figure 1 with the SAW chip and encapsulate the structure of wire-bonded each other, SAW device according to the present invention can also have other structures, and it can have wherein, and the electrode pad of SAW chip engages (FCB) structure with the terminal of encapsulation via the flip-chip that metal coupling is connected, wherein by the flip-chip mode with the SAW chip join on circuit board and to carrying out resin-sealed CSP (chip size packages) structure around the SAW chip, wherein needn't use WLCSP (encapsulation of the wafer scale size) structure of encapsulation or circuit board etc. by on the SAW chip, forming metal level or resin bed.Can adopt wherein and carry out AQP (full quartz packaged) structure stacked and that seal under the state in the middle of quartz is sandwiched in quartz base plate or glass substrate.Because the AQP structure is a structure of utilizing quartz base plate or glass substrate to sandwich simply, so do not need encapsulation, can carry out thinning, and can reduce the degassing (out gas) that adhesive causes by adopting the low-melting glass sealing or directly engaging, thereby can realize advantage such as the aging characteristics brilliance.
Claims (16)
1, a kind of surface acoustic wave device, this surface acoustic wave device comprise piezoelectric substrate and be formed on the described piezoelectric substrate and by Al or comprise the interdigitation electrode that Al forms as the alloy of main component, excited wave is the SH ripple, wherein,
Described piezoelectric substrate is the rotary Y cutting cutting board of being made by quartzy flat board,
The cutting angle θ of wherein said piezoelectric substrate is the anglec of rotation of Z crystallographic axis when described piezoelectric substrate rotates around the X crystallographic axis,
The direction that described piezoelectric substrate forwards positive Y-axis side to from positive Z sidespin is that described cutting angle θ is negative direction, and
Described cutting angle θ is set in the scope of-64.0 °＜θ＜-49.3 °, and the direction of propagation of surface acoustic wave is set to become 90 ° ± 5 ° with respect to the X crystallographic axis, and,
When will being excited the wavelength table of surface acoustic wave when being shown λ, be set to satisfy 0.04＜H/ λ＜0.12 by the electrode film thickness H/ λ of the standard of wavelengthization of described interdigitation electrode.
2, surface acoustic wave device according to claim 1, wherein, the relation between cutting angle θ and the electrode film thickness H/ λ satisfies-1.34082 * 10
-4* θ
3-2.34969 * 10
-2* θ
2-1.37506 * θ-26.7895＜H/ λ＜-1.02586 * 10
-4* θ
3-1.73238 * 10
-2* θ
2-0.977607 * θ-18.3420.
3, surface acoustic wave device according to claim 1, wherein, when the definition wires degree of metalization
The time, the relation between the product H/ λ * mr of cutting angle θ and electrode film thickness and line degree of metalization satisfies-8.04489 * 10
-5* θ
3-1.40981 * 10
-2* θ
2-0.825038 * θ-16.0737＜H/ λ * mr＜-6.15517 * 10
-5* θ
3-1.03943 * 10
-2* θ
2-0.586564 * θ-11.0052.
4, a kind of surface acoustic wave device, this surface acoustic wave device comprise piezoelectric substrate and be formed on the described piezoelectric substrate and by Al or comprise the interdigitation electrode that Al makes as the alloy of main component, utilize excited wave to be the SH ripple, wherein,
Described piezoelectric substrate is the rotary Y cutting cutting board of being made by quartzy flat board,
The cutting angle θ of wherein said piezoelectric substrate is the anglec of rotation of Z crystallographic axis when described piezoelectric substrate rotates around the X crystallographic axis,
The direction that described piezoelectric substrate forwards positive Y-axis side to from positive Z sidespin is that described cutting angle θ is negative direction, and
Described cutting angle θ is set in the scope of-61.4 °＜θ＜-51.1 °, and the direction of propagation of surface acoustic wave is set to become 90 ° ± 5 ° with respect to the X crystallographic axis, and,
When will being excited the wavelength table of surface acoustic wave when being shown λ, be set to satisfy 0.05＜H/ λ＜0.10 by the electrode film thickness H/ λ of the standard of wavelengthization of described interdigitation electrode.
5, surface acoustic wave device according to claim 4, wherein, the relation between cutting angle θ and the electrode film thickness H/ λ satisfies-1.44605 * 10
-4* θ
3-2.50690 * 10
-2* θ
2-1.45086 * θ-27.9464＜H/ λ＜-9.87591 * 10
-5* θ
3-1.70304 * 10
-2* θ
2-0.981173 * θ-18.7946.
6, surface acoustic wave device according to claim 4, wherein,
When the definition wires degree of metalization
The time, the relation between the product H/ λ * mr of cutting angle θ and electrode film thickness and line degree of metalization satisfies-8.67632 * 10
-5* θ
3-1.50414 * 10
-2* θ
2-0.870514 * θ-16.7678＜H/ λ * mr＜-5.92554 * 10
-5* θ
3-1.02183 * 10
-2* θ
2-0.588704 * θ-11.2768.
7, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is the port SAW (Surface Acoustic Wave) resonator that described piezoelectric substrate is provided with at least one interdigitation electrode.
8, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is the two port SAW (Surface Acoustic Wave) resonator that are provided with at least two interdigitation electrodes on described piezoelectric substrate along the direction of propagation of surface acoustic wave.
9, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is the lateral type multi-mode filter that is provided with a plurality of SAW (Surface Acoustic Wave) resonator on described piezoelectric substrate with the direction of propagation of surface acoustic wave abreast close to each other.
10, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is the longitudinally coupled multi-mode filter that is provided with the two-port SAW (Surface Acoustic Wave) resonator that comprises a plurality of interdigitation electrodes on described piezoelectric substrate along the direction of propagation of surface acoustic wave.
11, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is the ladder type surface acoustic wave filter that is connected with a plurality of SAW (Surface Acoustic Wave) resonator on described piezoelectric substrate by trapezoidal shape.
12, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is the transversal surface acoustic wave filter that is provided with a plurality of interdigitation electrodes of two-way ground propagation surface sound wave on described piezoelectric substrate by predetermined space.
13, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is that described piezoelectric substrate is provided with along the transversal surface acoustic wave filter of at least one interdigitation electrode of a direction propagation surface sound wave.
14, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device is a saw sensor.
15, according to each the described surface acoustic wave device in the claim 1 to 6, wherein,
Described surface acoustic wave device has grating reflector on the both sides of interdigitation electrode.
16, a kind of module device or oscillating circuit, this module device or oscillating circuit use according to each the described surface acoustic wave device in the claim 1 to 6.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004108608 | 2004-04-01 | ||
| JP108608/2004 | 2004-04-01 | ||
| JP310452/2004 | 2004-10-26 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1943109A CN1943109A (en) | 2007-04-04 |
| CN100539411C true CN100539411C (en) | 2009-09-09 |
Family
ID=37959878
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005800108867A Active CN100539411C (en) | 2004-04-01 | 2005-03-08 | Surface acoustic wave device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100539411C (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324908B (en) * | 2011-07-07 | 2014-05-21 | 中国电子科技集团公司第五十五研究所 | Surface acoustic wave device with superimposed quasiperiodic strip array structure |
| CN102497173B (en) * | 2011-12-19 | 2014-12-17 | 北京中讯四方科技股份有限公司 | Novel suspension electrode structure acoustic surface wave filter |
| CN105393455B (en) | 2013-06-28 | 2017-04-12 | 大河晶振科技有限公司 | Elastic wave device |
| JPWO2015137089A1 (en) | 2014-03-14 | 2017-04-06 | 株式会社村田製作所 | Elastic wave device |
| JP6020519B2 (en) * | 2014-06-20 | 2016-11-02 | 株式会社村田製作所 | Elastic wave device |
| DE102016105118A1 (en) * | 2016-03-18 | 2017-09-21 | Snaptrack, Inc. | SAW device with reduced interference due to transversal and SH modes and RF filter with SAW device |
| ES2806975T3 (en) * | 2016-07-11 | 2021-02-19 | Epitronic Holdings Pte Ltd | Surface Acoustic Wave RFID Sensor for Hemodynamic Wearable Accessories |
| JP2019062424A (en) * | 2017-09-27 | 2019-04-18 | 株式会社村田製作所 | Elastic wave device, high frequency front end circuit and communication device |
| JP7068835B2 (en) * | 2018-01-26 | 2022-05-17 | 太陽誘電株式会社 | Elastic wave devices, filters and multiplexers |
| JP7033462B2 (en) * | 2018-02-19 | 2022-03-10 | ＮＤＫ ＳＡＷ ｄｅｖｉｃｅｓ株式会社 | Surface acoustic wave device |
| FR3079053B1 (en) * | 2018-03-16 | 2020-03-27 | Frec'n'sys | COMPOSITE SUBSTRATES FOR SURFACE ACOUSTIC WAVE LABEL DEVICES FOR RFID AND SENSOR APPLICATIONS |
-
2005
- 2005-03-08 CN CNB2005800108867A patent/CN100539411C/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN1943109A (en) | 2007-04-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100539411C (en) | Surface acoustic wave device | |
| US7589451B2 (en) | Surface acoustic wave device | |
| US11742826B2 (en) | Quartz orientation for guided SAW devices | |
| US8803625B2 (en) | Surface acoustic wave resonator, surface acoustic wave oscillator, and surface acoustic wave module unit | |
| US7750533B2 (en) | Surface acoustic wave (SAW) device, module and oscillator for improving a Q factor | |
| US6985048B2 (en) | Surface acoustic wave apparatus and communication apparatus | |
| US20220069803A1 (en) | Elastic wave device, splitter, and communication apparatus | |
| EP1659687A1 (en) | Surface acoustic wave device and electronic apparatus | |
| WO2005125005A1 (en) | Saw device and apparatus employing it | |
| JP4148220B2 (en) | Surface acoustic wave device, composite device, oscillation circuit and module | |
| US20100289379A1 (en) | Surface acoustic wave (saw) device | |
| JP4582150B2 (en) | Surface acoustic wave device and module device or oscillation circuit using the same | |
| JP5158104B2 (en) | Surface acoustic wave resonator, surface acoustic wave oscillator, and surface acoustic wave module device | |
| JP4356773B2 (en) | Surface acoustic wave device and module device or oscillation circuit using the same | |
| JP2007019975A (en) | Surface acoustic wave device, module apparatus, and oscillation circuit | |
| JP4148216B2 (en) | Surface acoustic wave device and module device or oscillation circuit using the same | |
| JP2007019976A (en) | Longitudinally coupled multiple mode surface acoustic wave filter, and module apparatus | |
| JP2007013682A (en) | Surface acoustic wave device | |
| JP2007325084A (en) | Surface acoustic wave element piece and surface acoustic wave device | |
| JP2005102328A (en) | Acoustic surface wave device | |
| JP2013085273A (en) | Surface acoustic wave resonator, surface acoustic wave oscillator and surface acoustic wave module device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: SEIKO EPSON CORP. Free format text: FORMER OWNER: EPSON TOYOCOM CORP. Effective date: 20111018 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20111018 Address after: Tokyo, Japan, Japan Patentee after: Seiko Epson Corp. Address before: Tokyo, Japan, Japan Patentee before: Epson Toyocom Corp. |