CN1830098A - Laminate type electronic component and production method therefor, laminate type piezoelectric element and jet device - Google Patents
Laminate type electronic component and production method therefor, laminate type piezoelectric element and jet device Download PDFInfo
- Publication number
- CN1830098A CN1830098A CNA2004800215169A CN200480021516A CN1830098A CN 1830098 A CN1830098 A CN 1830098A CN A2004800215169 A CNA2004800215169 A CN A2004800215169A CN 200480021516 A CN200480021516 A CN 200480021516A CN 1830098 A CN1830098 A CN 1830098A
- Authority
- CN
- China
- Prior art keywords
- internal electrode
- laminate type
- piezoelectric element
- piezoelectrics
- type piezoelectric
- 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.)
- Granted
Links
Images
Abstract
In order to provide a multi-layer electronic component in which the occurrence of delamination between the ceramic layer and the internal electrode is restricted and a method for manufacturing the same, the multi-layer electronic component of the present invention comprises a stack formed by stacking piezoelectric layers and internal electrodes one on another alternately and a pair of external electrodes formed on two opposing side faces of the stack, wherein the internal electrode consists of a first internal electrode connected to the external electrode formed on one of the two side faces and a second internal electrode located between the first internal electrode and connected to the external electrode formed on the other one of the two side faces, and wherein the internal electrodes and the piezoelectric layers are faced in proximity so that a space between them is 2 m or less over an area occupying 50% or more of the active region where the first internal electrode and the second internal electrode oppose each other.
Description
Technical field
The present invention relates to laminate type electronic component and manufacture method thereof, particularly adopt laminate type piezoelectric element and element thereof and the injection apparatus that constitutes.More particularly, relate to be assemblied in the fuel injection device of car engine as driving element, the liquid injection apparatus of ink-jet etc., precision positioning device such as Optical devices and anti-vibration device etc. are gone up and adopted laminate type piezoelectric element, be assemblied in the burning pressure sensor, knock transducer, acceleration transducer, load sensor, ultrasonic sensor, the pressure-sensitive transducer, sensing element on the angular-rate sensor etc., and be installed in piezoelectric gyroscope as circuit element, Piezoelectric switches, piezoelectric transformer, piezoelectricity circuit breakers etc. are gone up and the device of adopted laminate type piezoelectric element.
Background technology
In the past,, for example, obtained big displacement, and had suggestion piezoelectrics and internal electrode to be carried out the laminate type piezoelectric element of alternative stacked in order to utilize the electrostriction effect as laminate type electronic component.Laminate type piezoelectric element is divided into two kinds of superimposed type of burning till type and piezoelectric ceramic and internal electrode alternative stacked simultaneously, but considers lower voltage, reduction cost of manufacture etc., and the laminate type piezoelectric element that burns till type simultaneously is favourable to thin layerization.
Burn till the laminate type piezoelectric element of type simultaneously, identical with laminated ceramic capacitor, in the top and bottom of the raw cook that contains piezoelectric with the active portion of the internal electrode pattern alternative stacked that contains the internal electrode material, with above-mentioned ceramic green sheet lamination and the inertia portion that forms carries out lamination repeatedly, and with its degreasing, burn till and make.
, in recent years, for example,, just apply higher electric field, and make it carry out long-term Continuous Drive in order to ensure the big displacement quantity of small-sized lamination-type piezoelectric actuator (piezoelectric actuator) under big pressure.
In order to respond this requirement, open in the laminate type electronic component that flat 4-299588 communique clearly shows the spy, in internal electrode, by on 1/2～1 times particle diameter of internal electrode thickness, containing 10～20% controlled ceramic powders, rely on the column between the ceramic layer to connect, the interface of internal electrode and ceramic layer produces and peels off after preventing to burn till.
Yet, Te Kaiping 4-299588 communique the laminate type electronic component clearly showed, because internal electrode and outer electrode cooling rate when the heat treatment that is connected operation is fast, as shown in Figure 5, because the thermal coefficient of expansion of internal electrode 102 and ceramic layer 101 is poor, in stylolitic part 51 non-existent parts, is crossing over almost whole interface, gapped between internal electrode and ceramic layer, account for whole more than 50% greater than the part of the gap T of 2 μ m.If therefore apply higher electric field, make its long-term Continuous Drive just have the problem that splitting takes place.
In addition, Te Kaiping 5-217796 communique the laminate type electronic component clearly showed, by higher firing temperature when burning till for the first time the machining section (outer electrode formation face) of element is heat-treated, eliminate the fine crack that when cut, produces the former of short circuit thereby formation.
Yet because the speed of cooling is very fast when heat-treating with the temperature higher than firing temperature, poor because of the thermal coefficient of expansion of internal electrode and ceramic layer all produced and peeled off almost crossing over whole interface.If therefore apply higher electric field and make its long-term Continuous Drive, just there is the problem that splitting takes place.
In addition, Fig. 7, be the spy open clear 61-133715 communique the device of the expression laminate type piezoelectric element clearly showed, this element is made of laminated body 200 and the mutual relative a pair of outer electrode that forms in the side 223.Laminated body 200 constitutes by constituting its piezoelectrics 221 and internal electrode 222 alternative stacked, but internal electrode 222 is constructed and form so-called partial electrode in the whole interarea formation of piezoelectrics 221.The internal electrode 222 of this partial electrode structure is exposed every the side of the different laminated body 200 of a course, about stacked piezoelectric body alternately.Moreover, at two end face lamination inert layers 224 of the stack direction of laminated body 200.Then, the laminated body 200 mutual relative a pair of internal electrodes 222 that expose the side are interconnected and form outer electrode 223, thus internal electrode 222 interlayers are connected.
Manufacture method as in the past laminate type piezoelectric element, on the ceramic green sheet that contains piezoelectrics 221 raw materials, with internal electrode slurry by the fixed formed pattern of electrode structure print, with the raw cook that scribbles this internal electrode slurry lamination and obtain produced lamination organizator repeatedly,, it makes laminated body 200 by being burnt till.After this, obtain formed laminate type piezoelectric element by on a pair of side of laminated body 200, burning till outer electrode 23.
Moreover, as internal electrode 222, adopt the alloy of silver and palladium, and for piezoelectrics 221 and internal electrode 222 are burnt till simultaneously, the metal ingredient of internal electrode 222, adopt silver for weight 70%, palladium be weight 30% ratio (for example, with reference to real open flat 1-130568 communique with reference to).
Like this, internal electrode 222 is not only to be become to be grouped into by silver metal, but employing contains the internal electrode 222 that the metal ingredient by argentiferous-palldium alloy of palladium is formed, the reason of doing like this is if only be made up of the silver that does not contain palladium, when giving when applying potential difference between a pair of relative internal electrode 222, in this pair of internal electrodes 222, will produce silver in the electrode produce along the element surface transmission to negative pole from positive pole mobile, thereby produce so-called silver migration existing as.This existing as, in the environment of high temperature, high humidity, significantly take place.
When laminate type piezoelectric element that will be in the past uses as piezoelectric actuator, externally further lead is fixed (not having diagram) by scolding tin on the electrode 223, externally add between the electrode 223 fixed current potential and make its driving.Particularly in recent years, small-sized laminate type piezoelectric element in order to ensure desired big displacement quantity, is applying higher electric field under big pressure, make its Continuous Drive chronically.
Burn till the laminate type piezoelectric element of type in the time of such, just require the sintering temperature of internal electrode 222 consistent, thereby the material that internal electrode 222 and piezoelectrics 221 are being discussed is always formed with the sintering temperature of piezoelectrics 221.Yet, only depend on these, because the caused residual stress of thermal expansion difference because of internal electrode 222 and piezoelectrics 221, concentrate on the crystal grain with the piezoelectrics 221 on internal electrode 222 opposites, when using as driver, internal electrode 222 will be peeled off from piezoelectrics 221 in driving, thereby has the problem of so-called splitting (delamination).
Particularly at the intragranular of piezoelectrics 221, when with the crystal grain of the piezoelectrics 221 on internal electrode 222 opposites hour, the particle permittivity that will become bigger than same composition because of dimensional effect is little, thus produce little existing of displacement bimorph amount as.In addition, even only strengthen the average crystal grain of the crystal grain of piezoelectrics 221, with the crystal grain of the piezoelectrics 221 on internal electrode 222 opposites in, if there is the little particle of displacement bimorph amount to exist, because the displacement in driving is littler than the crystal grain of other piezoelectrics 221, so, thereby become the problem that cracks with the starting point of splitting with regard to existence because of the caused residual stress of thermal expansion difference of internal electrode 222 and piezoelectrics 221 just is concentrated on 1.
In addition, since the generation of this splitting, the problem that also has so-called driver displacement to change.Particularly when the incidence of splitting became big, component temperature rose, in case to such an extent as to surpassing heat dissipation capacity, this component temperature will produce the existing as damage of thermal runaway, thus the sharply aging problem of displacement is arranged.Therefore, for the suppression element temperature rises, need the little internal electrode of resistivity.
Yet, the resistivity value of the silver-palladium alloy that always uses in the past, because of its ratio of components, resistivity is all higher significantly than the resistivity of silver or palladium monomer, with silver account for weight 70%, palladium accounts for the composition of 30% silver-palladium alloy of weight, its resistance has the problem higher 1.5 times than palladium monomer.And if the sintered density of internal electrode 222 is low, its resistance can be higher, thereby obtain the little internal electrode of resistivity 222 limit is arranged.
As above-mentioned, when adopting the driving element that will laminate type piezoelectric element in the past be used for fuel injection device etc. as driver, desirable displacement gradually changes and the problem of generation device misoperation.Therefore need when move continuously for a long time, suppress the variation of displacement and improve durability.
In addition, to laminate type piezoelectric element, apply the processing (for example, the spy opens the 2002-293625 communique) that polarizes of voltage about 1kv.Specifically, the spy open in the 2002-293625 communique the polarization clearly showed handle, be to form the laminate type piezoelectric element of outer electrode, soak in the oil-bath of heating (1), (2) apply voltage, the process that (3) voltage cools off after descending.
Yet, the spy open the 2002-293625 communique in the polarization treatment conditions of clearly showing, to constituting the crystal grain of piezoelectric body layer, can not carry out fully saturated polarization, for example in long-term driving test, particularly in the piezoelectric property, there is the problem of displacement decline.This problem is because of the crystal grain that constitutes piezoelectric body layer, big in the degree of orientation rate of change change that drives front and back.
Summary of the invention
The present invention puts in view of the above-mentioned problems and forms, and its objective is provides a kind of laminate type electronic component that suppresses the splitting between ceramic layer and the internal electrode to provide and manufacture method.
Even its purpose particularly provides a kind of and makes under the situation of its long-term Continuous Drive with high voltage, high pressure, be suppressed at the splitting that takes place in the driving, and do not have displacement to change laminate type piezoelectric element and injection apparatus with outstanding durability.
In addition, the objective of the invention is to dwindle degree of orientation rate of change crystal grain, that drive front and back that constitutes piezoelectric body layer, even in long-term driving test, laminate type piezoelectric element that the reduction of piezoelectric property is also very little and manufacture method thereof, and the injection apparatus that adopts this laminate type piezoelectric element.
In order to reach above purpose, laminate type electronic component of the present invention is characterized in that, has: piezoelectric body layer and internal electrode alternative stacked and the laminated body that constitutes; The pair of external electrodes that on two relative sides of this laminated body, forms,
Above-mentioned internal electrode is by first internal electrode that is connected the said external electrode that its side forms in the side in above-mentioned two sides, and between above-mentioned first internal electrode and second internal electrode that on the another side, is connected the said external electrode that its side forms form.
Above-mentioned internal electrode and above-mentioned piezoelectric body layer, in the part more than 50% of the active region that faces toward of above-mentioned first internal electrode and above-mentioned second internal electrode, with less than the interval of 2 μ m near and overlapping.
Here, the zone that faces toward of above-mentioned first internal electrode and above-mentioned second internal electrode is the part of moving as laminate type electronic component, and in this manual, the active region is active portion again.Simultaneously, the side in above-mentioned first internal electrode and above-mentioned second internal electrode is positive pole, and opposite side is a negative pole.
Simultaneously, in laminate type electronic component of the present invention, in the case, constitute the rate of change of the degree of orientation of the crystal grain of piezoelectric body layer, after repeating to drive, be suppressed at 5% with interior be preferred.
Like this, drop to below 5% if will constitute the rate of change of crystal grain degree of orientation before and after driving of piezoelectric body layer, even after long-term the use, piezoelectric property, particularly displacement can reduce, thereby can obtain very high reliability.
And when above-mentioned ceramic layer during as piezoelectric body layer, the average grain diameter of the crystal grain of above-mentioned piezoelectric body layer is to be preferred below the 2.5 μ m.If constituting the average grain diameter of the crystal grain of piezoelectric body layer is below the 2.5 μ m, then can improves the degree of orientation of crystal grain in polarization is handled, and can dwindle the rate of change of the polarizability of piezoelectric property.
With the of the present invention laminate type piezoelectric element of above above-mentioned ceramic layer, for example, for 150kgf, temperature are that 150 ℃, frequency are under the condition of 50Hz, carry out 10 at load as piezoelectric body layer
9Also seldom aging after repeating more than inferior to drive, needing also to be very suitable for the such device of injection apparatus of the high reliability of Continuous Drive.
In addition, when above-mentioned ceramic layer during as piezoelectric body layer, the thickness of piezoelectric body layer is to be preferred below the 200 μ m, can apply very high electric field to thickness direction thus, thereby can carry out saturated polarization.
In addition, the thickness of above-mentioned internal electrode in order to improve the conductivity of internal electrode thickness direction, is preferred below the 5 μ m, thus, for example can further improve the degree of orientation and the polarizability of the crystal grain that constitutes piezoelectric body layer.
In addition, in above-mentioned internal electrode, outside the metal as its principal component, can also contain inorganic constituents.
In above-mentioned laminate type piezoelectric element, when in making internal electrode, containing inorganic constituents, this inorganic constituents, identical with piezoelectric body layer is preferred, and the average grain diameter of inorganic constituents is preferred than the average grain diameter of piezoelectric body layer for a short time.
Like this, in the present invention, internal electrode is contained and the identical inorganic constituents of piezoelectrics particle that constitutes piezoelectric body layer, and the size ratio piezoelectric body layer side by the internal electrode side is little, the piezoelectrics particle of contact internal electrode is diminished, and the effective area that can make internal electrode thus is when increasing, by adding the rising that inorganic constituents suppresses the internal electrode rigidity, thereby can improve the being adjacent to property with piezoelectric body layer, and can apply high electric field.
In addition, the manufacture method of laminate type electronic component of the present invention is characterized in that, has: the operation of making the column laminated body that is formed by a plurality of ceramic layers and a plurality of internal electrode alternative stacked ground; The column laminated body is processed into the operation of desirable size; The operation that this column laminated body is heat-treated; In this column laminated body side, coat the operation of conductive paste; This conductive paste is heat-treated, make the operation of carrying out interconnective pair of external electrodes with above-mentioned internal electrode interlayer; To the said external electrode application voltage, will be as the rate of change of the c/a of the ratio of lattice constant to less than 0.5% operation that polarizes and handle.
In addition, the manufacture method of laminate type electronic component of the present invention, in heat treated operation, when the Curie temperature of above-mentioned ceramic layer as t (℃) time, be preferred from the cooling rate of heat treated maximum temperature less than t/3 (℃/minute).
In addition, the manufacture method of laminate type electronic component of the present invention, in heat treated operation, when heat treatment was cooled off, the cooling rate of the temperature province of 1.2t～0.8t was preferred especially less than t/3 (℃/minute).
As above being described in detail, according to laminate type electronic component of the present invention, can suppressing the generation of splitting, thereby the laminate type electronic component with high reliability can be provided.
Second laminate type piezoelectric element of the present invention comprises piezoelectrics and internal electrode alternative stacked and the laminated body that constitutes, it is characterized in that: the average crystallite particle diameter of the above-mentioned internal electrode part of the contact of above-mentioned piezoelectrics is also bigger than its average crystallite grain with exterior domain.
In addition, the 3rd lamination-type piezoelectric element of the present invention, the laminated body that comprises piezoelectrics and internal electrode alternative stacked and constitute is characterized in that: the minimum knot crystal grain footpath of the above-mentioned internal electrode part of the contact of above-mentioned piezoelectrics, and directly also bigger than its minimum knot crystal grain with exterior domain.
And, injection apparatus of the present invention, be to be provided with the container that has towards the spray-hole of fuel passage, be accommodated in the piston that carries out switch between inherent above-mentioned fuel passage of said vesse and the spray-hole, be accommodated in the injection apparatus that drives the laminate type piezoelectric element of above-mentioned piston in the said vesse and form, it is characterized in that: above-mentioned laminate type piezoelectric element, be the laminate type piezoelectric element of the laminated body that constitutes comprising piezoelectrics and internal electrode alternative stacked, its average crystallite particle diameter with exterior domain of average crystallite size ratio of the above-mentioned internal electrode part of the contact of above-mentioned piezoelectrics is also big.
According to above such the of the present invention second and the 3rd lamination-type piezoelectric element that constitutes, the average crystallite particle diameter or the minimum crystallization particle diameter of the piezoelectrics by will contacting internal electrode, make also greatlyyer, the residual stress that internal electrode and piezoelectrics cause because of thermal expansion difference can be disperseed piezoelectrics particle the samely to electrode interface than its average crystallite particle diameter or minimum crystallization particle diameter with exterior domain.Thus, because can strengthen the intensity that is adjacent at internal electrode and piezoelectrics interface, thus can suppress splitting, and the high reliability piezoelectric actuator that wears out, has outstanding durability that is suppressed at displacement in the driving can be provided.
In addition, even laminate type piezoelectric element Continuous Drive of the present invention, desirable displacement does not have effective the variation yet, can realize not having the misoperation operation so contain the injection apparatus of laminate type piezoelectric element, and the injection apparatus of the high reliability with outstanding durability can be provided.
Description of drawings
Fig. 1 is the side view of the laminate type electronic component of embodiments of the present invention 1.
Fig. 2 is the plane graph of potsherd that constitutes the laminate type electronic component of execution mode 1.
Fig. 3 is the open cube display of lamination organizator that constitutes the laminate type electronic component of execution mode 1.
Fig. 4 is the profile of laminated structure that constitutes the laminate type electronic component of execution mode 1.
Fig. 5 is the figure that represents defective between the ceramic layer of laminate type electronic component in the past and the internal electrode.
Fig. 6 A is the stereogram that the laminate type piezoelectric element of expression embodiments of the present invention 2 constitutes.
Fig. 6 B is the exploded perspective view that is illustrated in the layer-by-layer state of piezoelectric body layer and internal electrode in the execution mode 2.
Fig. 7 is a stereogram of representing that stacked capacitor in the past constitutes.
Fig. 8 is the profile of the formation of expression injection apparatus of the present invention.
Fig. 9 is the fragmentary cross-sectional view of the laminate type piezoelectric element of embodiments of the present invention 3.
Figure 10 A～Figure 10 C is a process chart of making the laminate type piezoelectric element of execution mode 3.
Figure 11 is the flow chart of the polarization treatment process of expression execution mode 3.
Embodiment
Fig. 1 is the longitudinal sectional drawing that the laminate type electronic component (lamination-type piezoelectric actuator) of expression embodiments of the present invention 1 constitutes.
The lamination-type piezoelectron parts of present embodiment 1, has the active portion 8 that a plurality of ceramic layers 1 and a plurality of internal electrode 2 alternative stacked form as shown in Figure 1, the column laminated body 3 of the tetragonal column of forming by the inertia portion 9 that is arranged at the stack direction two ends of this active portion 8.
In addition, the thickness of ceramic layer 1, the distance between the internal electrode 2 just is from miniaturization and apply high electric field to be seen as 0.05～0.25mm best.This is because laminate type piezoelectric element applies voltage, adopt the method that increases the lamination number in order to obtain big displacement, if but increase the lamination number, the thickness of the ceramic layer 1 in the active portion 8 will be too thick, thereby can not make driver miniaturization, dwarf formsization, on the other hand, if too thin insulating is breakdown easily for the thickness of the ceramic layer 1 in the active portion 8.
Then in the laminate type electronic component of present embodiment 1, be part below the 2 μ m to the gap of internal electrode 2 and ceramic layer 1, the opposite face integral body of internal electrode 2 and ceramic layer 1 is reached 50% manage abovely.Like this, in the laminate type electronic component of present embodiment 1, the gap of internal electrode 2 and ceramic layer 1 is the following parts of 2 μ m, extremely important more than 50% for the substantial activity part, the generation of splitting, crackle etc. can be suppressed thus, highly reliable performance can be obtained.
The gap of internal electrode 2 and ceramic layer 1 is the part less than 2 μ m, if lack than 50% of substantial activity part, when it is driven, will crack from gap portion, thereby the danger that destroys reliability is arranged.Particularly,, obtain high reliability, preferably make the gap of internal electrode 2 and ceramic layer 1 be part, reach more than 70% of substantial activity part less than 2 μ m in order to reduce the origination point of crackle.
In addition, the manufacture method of laminate type electronic component of the present invention, at first, with lead zirconate titanate Pb (Zr, Ti) O
3Burn powder (ceramic powders), acrylic resin, the organic bond formed by organic polymers such as butyral resins, mix with plasticizer and make slip Deng the standard of piezoelectrics pottery, for example by the slurry molding casting, producing as shown in Figure 2, thickness is the ceramic green sheet 21 of 50～250 μ m.
In the present invention, the accurate average grain diameter of burning powder of the pottery of formation ceramic layer 2 (being contained in the ceramic green sheet 21) is preferably 0.3～0.9 μ m.Make more than the 0.3 μ m by the average grain diameter of the standard of pottery being burnt powder, when making ceramic green sheet 21, can reduce the amount that prevents the needed organic bond of season cracking.
On the other hand, make below the 0.9 μ m by the average grain diameter of the standard of pottery being burnt powder, when burning till, can carry out abundant sintering, and can improve the intensity of pottery, for example in laminate type piezoelectric element, can suppress generation because of the caused crackle of stress of electric field generation.
In addition, the thickness of ceramic green sheet 21 is preferred in order to improve the dielectric strength of burning till back ceramic layer 1, to make more than the 90 μ m, more preferably, makes more than the 100 μ m.In addition, in order to prevent when handling ceramic green sheet 21, to crack,, preferably adopt to have high-tensile butyral resin as organic bond.
Then, after the ceramic green sheet of making 21 got through by institute's sizing, on the one side of ceramic green sheet 21, the conductive paste that contains silver-palladium and solvent that will become internal electrode 2 prints with the thickness of silk screen print method with 1～10 μ m as shown in Figure 2, and dry back forms inner conductor pattern 22.
Then, as shown in Figure 3, the ceramic green sheet 21 of inner conductor pattern 22 will be formed, alternately expose in the opposite flank of end of inner conductor pattern 22 and lamination organizator 23 and only produce active portion lamination organizator 23a by deciding number lamination, top and bottom at this active portion lamination organizator 23a, the organizator 23b of the inertia portion lamination that will not have more than 21 lamination of ceramic green sheet of printing conductive paste and form is produced lamination organizator 23.
Moreover, can more than 21 lamination of ceramic green sheet of printing conductive paste will do not had yet, after producing the lamination organizator 23b of inertia portion of downside, on the lamination organizator 23b of this inertia portion, with a plurality of ceramic green sheets 21 that formed inner conductor pattern 22 only press fixed number lamination and lamination active portion lamination organizator 23a, on this active portion lamination organizator 23a, repeatedly lamination does not have the ceramic green sheet 21 of printing conductive paste, the lamination organizator 23b of inertia portion of lamination upside makes lamination organizator 23.
Moreover, about the manufacture method of lamination organizator 23, be not subjected to special qualification, as long as it is just passable to obtain the lamination organizator 23 of ceramic green sheet 21 and inner conductor pattern 22 laminations.
Then, an end heats an end to these lamination organizator 23 pressurizations, makes lamination organizator 23 integrated, thereby obtains column laminated body organizator.
In addition, as the method for pressurization, pressurize from the most handy hydrostatic pressing of a bit seeing that improves the lamination precision, its pressure is preferably 20～120MPa.
Incorporate column laminated body organizator by after the cutting of institute sizing, with 400～800 ℃ of degreasings of carrying out 5～40 hours, afterwards, is carried out 2～5 hours formally burn till in atmosphere, just obtain column laminated body 3 shown in Figure 4 in 900～1200 ℃.This column laminated body 3 has the active portion of ceramic layer (piezoelectric body layer) 1 and internal electrode 2 alternative stacked, on its relative side, alternately exposes an end of internal electrode 2.
Then, apply the direct voltage of 0.1～3kVmm,, finish as the laminate type electronic component of product by processing that the column laminated body is polarized to pair of external electrodes 4.Here, the rate of change of c/a before and after polarization as the ratio of lattice constant is extremely important less than 0.5%.Because if the rate of change of c/a is bigger than 0.5%, the stress that produces during owing to polarization will produce between internal electrode 2 and ceramic layer 1 and peel off.In the present invention, what stress produced in order to prevent to polarize peels off, and the rate of change of c/a is preferably less than 0.2%.Here, the ratio c/a of lattice constant asks lattice constant a from the XRD diffraction pattern by the peak value of the indices of crystallographic plane (200), similarly asks lattice constant c by the peak value of the indices of crystallographic plane (002), asks c/a by these numerical value again.
By adopting above manufacture method, the interfacial gap of internal electrode 2 and ceramic layer 1 can be made less than 2 μ m.If the gap of internal electrode 2 and ceramic layer 1 is bigger than 2 μ m, when applying high voltage, will crack from the gap, if or long-term Continuous Drive will crack from the gap, thereby reliability is reduced.Laminate type electronic component of the present invention can prevent to peel off, but in actual operation because of the sneaking into of foreign matter, also can produce a part than the big interfacial gap of 2 μ m, but as long as less than the gap portion of 2 μ m be active portion just can guarantee its reliability more than 50%.
Then, as shown in Figure 1, on the side of exposing in the end of the internal electrode 2 of column laminated body 3, coating with silver is the silver-colored glass cream of principal component, by maximum temperature from 500～900 ℃, to the Curie temperature t of above-mentioned ceramic layer 1 (℃), with the heat treatment of cooling off, form outer electrode 4 less than the speed of t/3 (℃/minute).Thus, internal electrode 2 alternately interlayer be connected respectively with outer electrode 4.
If cooling rate is faster than t/3 (℃/minute), the difference of the thermal coefficient of expansion of electrode 2 and ceramic layer 1 produces stress at the interface internally, thereby splitting or crackle take place.
Particularly 1.2t～0.8t (℃) temperature in, cooling rate is preferably t/3 (℃/minute).If temperature is than Curie temperature height, ceramic layer 1 is a cube crystalline substance, if temperature is lower than Curie temperature, will form rhombohedral crystal or regular crystal, so in the temperature province that crystallizing layer changes,, just be easy to generate splitting because of crystallizing layer changes the internal stress that causes if cooling rate is fast.
,, adopt inspection here by ultrasonic detection as the method in the gap of confirming internal electrode 2 and ceramic layer 1, or the SEM of fracture.Just can check at an easy rate from lossless manner that the angle of the gap distribution that laminate type electronic component is all is seen and preferably adopt ultrasonic detection, but the SEM that observes fracture can also confirm the size of actual gap.Here, observe by SEM if section is carried out mirror finish, even there is actual gap, also the ductility because of internal electrode 2 makes internal electrode 2 extend to the gap, so observe very important from fracture again.By looking into ultrasonic wave detective triage, observe the result of vertical plane gained from stack direction, in the substantial activity part, the area of the part that takes place to peel off more than the 2 μ m and unstripped part is compared the ratio of peeling off that calculates.
Look into ultrasonic wave detective triage, also can once observe a plurality of layers section.In general, if look into the depth of focus dark with ultrasonic wave detective triage, its sensitivity will reduce, so it is many to the lamination number, highly be that 5mm is above, preferably vertically cut, cut apart the height of 2～5mm, look into by it being carried out ultrasonic wave detective triage respectively, and calculate the ratio of peeling off from stack direction.At the stress that produces because of driving or because of the stress of electric field generation, the stress that produces because of buckling etc., become a part of destroying the starting point part easily, particularly near the stack direction top and the bottom and near at least a portion the central portion, the gap of internal electrode 2 and ceramic layer 1 is the part less than 2 μ m, and the content active part is just passable more than 50%.
And, in above-mentioned form, as shown in Figure 3, made a column laminated body by a lamination organizator 23, certainly on a ceramic green sheet 21, form a plurality of inner conductor patterns, and this ceramic green sheet 21 carried out repeatedly lamination, produce the female lamination organizator that to make a plurality of column laminated body organizators, this lamination organizator is cut with institute's sizing, the manufacture method of the laminate type electronic component of a plurality of column laminated body organizators as shown in Figure 2 of producing once out also can be suitable for the present invention again.
Moreover, laminate type electronic component of the present invention, in order to prevent the interface peel of internal electrode 2 and ceramic layer 1, the ratio of internal electrode 2 that accounts for the lamination section is high more good more.The ratio that particularly is applicable to internal electrode 2 is the situation more than 70%.
Moreover the manufacture method of laminate type electronic component of the present invention is applicable to the manufacture method of laminate type electronic components such as lamination-type piezoelectric transformer, lamination-type capacitor, lamination-type piezoelectric actuator.Particularly in high electric field, carry out lamination-type piezoelectric actuator Continuous Drive, that adopt piezoelectric ceramic, be applicable to the manufacture method of laminate type electronic component of the present invention.
Laminate type piezoelectric element at embodiments of the present invention 2 is elaborated below.
Fig. 6 A is the stereogram that the laminate type piezoelectric element of expression present embodiment 2 constitutes, and Fig. 6 B is the in-built exploded perspective view of laminate type piezoelectric element of expression execution mode 2, the layer-by-layer state of expression piezoelectric body layer and internal electrode.
The laminate type piezoelectric element of present embodiment 2, shown in Fig. 6 A, B, on a pair of relative side of the laminated body 13 that piezoelectrics 11 and internal electrode 12 alternative stacked form, the end of the internal electrode 12 that respectively interlayer is exposed conducts and is connected with outer electrode 15.Here, the layer at the stack direction two ends of laminated body 13 is layer of being formed by a plurality of piezoelectrics 11 laminations of holding electrode layer not, on this layer owing to when moving, do not apply voltage, do not produce flexible, so be called inert layer 14.When the laminate type piezoelectric element of the present embodiment 2 that constitutes was like this used as the lamination-type piezoelectric actuator, outer electrode 15 was connected and fixed lead by scolding tin, and is connected above-mentioned lead just passable with the external voltage supply unit.
Between piezoelectrics 11, in the active region that has disposed the internal electrode of forming by metal materials such as silver-palladiums 12, by this internal electrode 12 to each piezoelectrics 11 with fixed voltage power up, piezoelectrics 11 produce displacement because of inverse piezoelectric effect.
Relative with it, inert layer 14 is owing to be there not being internal electrode 12 to be configured in the layer of a plurality of piezoelectrics 11, so also do not produce displacement even apply voltage.
The laminate type piezoelectric element of present embodiment 2 at the average crystallite particle diameter facing to the piezoelectrics 11 of internal electrode 12, has than it with the big feature of the average crystallite particle diameter of exterior domain, can obtain peculiar effect described later thus.,, be called near the zone the boundary face that contact with internal electrode 12 here, also comprise near the zone that internal electrode 12 peripheries are facing to the zone of the so-called piezoelectrics 11 of internal electrode 12.
In present embodiment 2, particularly with the average crystallite particle diameter of the piezoelectrics 11 on internal electrode 12 opposites for being preferred less than 8 μ m greater than 1 μ m.
If also littler of the little problem of electric displacement quantitative change will take place dimensional effect than 1 μ m, meanwhile bending strength is that so-called ceramics strength is little.In addition, if surpass 8 μ m, destroy variation because failure mode destroys to intragranular from the grain boundary, bending strength is that so-called pottery will intensity diminish.
In addition, in present embodiment form 2, face toward the minimum knot crystal grain footpath of the piezoelectrics 11 of internal electrode 12, also can be bigger than its minimum knot crystal grain with exterior domain.
, why proposing minimum knot crystal grain footpath here, is owing to concentrate because of the residual stress of thermal expansion difference at internal electrode 12 and piezoelectrics 11, is in the crystal grain at the interface of internal electrode 12, the crystal grain that crystal grain diameter is little.
Measure such average crystallite particle diameter and minimum knot crystal grain footpath and can adopt SEM (scanning electron microscope), specifically, when measuring the average crystallite particle diameter of the piezoelectrics 11 that face toward internal electrode 12, on the image of the crystal grain of the piezoelectrics 11 that face toward internal electrode 12 on the resultant image, draw straight line with SEM, in the arbitrfary point, select 50 crystal grain, the mean value of straight line crosscut length on each particle is stipulated as the average crystallite particle diameter.And, the present invention has stipulated facing to the average crystallite particle diameter of the piezoelectrics 11 of the internal electrode 12 average crystallite particle diameter with exterior domain, but the measurement of its average crystallite particle diameter also is that the straight line of dot-dash at random of the zones of different of measured zone beyond the piezoelectrics 11 that face toward internal electrode 12 is measured, and in addition measures in the same manner with above-mentioned measurement.
Moreover, minimum knot crystal grain footpath, for will above-mentioned 2 places (facing to the zone of the piezoelectrics of internal electrode 12 and in addition) average crystallite particle diameter of measuring and in the crystal grain in identical image place, the crystal grain diameter minimum.
In present embodiment 2, as the average crystallite size ratio of piezoelectrics 11 that will be relative with internal electrode 12 its with the big method of the average crystallite particle diameter of exterior domain, in manufacturing process, the sintering of internal electrode 12 beginning sintering is begun temperature begin the low temperature ground selected material of temperature than the sintering of piezoelectrics 11 beginning sintering and form.
More particularly, on the interface of piezoelectrics 11 and internal electrode 12, make sintering begin the low temperature formation liquid phase of temperature than piezoelectrics 11 beginning sintering, for example, in electrode slurry, with the metal dust that constitutes internal electrode 12, the powder that adds its metal oxide pattern that prints electrode.
Like this, begin temperature by the sintering with internal electrode 12 beginning sintering and begin the low mode of temperature than the sintering that piezoelectrics 11 begin sintering, when burning till at the same time, generate liquid phase at first in internal electrode 12 parts, the sintering of internal electrode 12 is proceeded.
And, when internal electrode 12 sintering,, make piezoelectrics 11 and internal electrode 12 liquid-phase sinterings by the generation of liquid phase.
Promptly, on electrode interface, form in the liquid phase energetically, also carrying out with the sintering of the piezoelectrics pottery of internal electrode 12 contact portions, eliminate by the carrying out of sintering from the little part of electrode interface pottery particle diameter, the ceramic particle diameter of contact internal electrode 12 parts becomes big, and being adjacent to of electrode interface just becomes firm.
In addition, by above-mentioned manufacture method, can make facing to brilliant other parts of size ratio of the minimum knot of the piezoelectrics 11 of internal electrode 12 big.But, in order will directly to become greatly facing to the minimum knot crystal grain of the piezoelectrics 11 of internal electrode 12, formed liquid phase need be to piezoelectrics 11 diffusions, therefore with this liquid phase formation temperature when sintering for electrode, after keeping firing temperature, as the temperature of piezoelectrics 11 sintering.
In present embodiment 2, the metal ingredient thing in the internal electrode 12 preferably with VIII family metal and/or Ib family metal as principal component.These materials are because above-mentioned metal ingredient thing has high-fire resistance, so piezoelectrics 11 and internal electrode 12 that can firing temperature is high burn till simultaneously.
And, metal ingredient thing in internal electrode 12, with VIII family metal and Ib family metal during as principal component, when the amount that is M1 (quality %), Ib family metal to the amount of VIII family metal is M2 (quality %), set its ratio of components to such an extent that satisfied 0＜M1≤15,85≤M2＜100, M1+M2=100 are preferred.
This be because, if VIII family metal overweight 15%, the resistivity of internal electrode 12 will become greatly, when making its Continuous Drive laminate type piezoelectric element, internal electrode 12 will generate heat sometimes.In addition, in order to suppress in the internal electrode 2 Ib family metal to piezoelectrics 11 migrations, with VIII family metal be weight 0.001% above weight be preferred below 15%.In addition, on the durability that improves laminate type piezoelectric element, 0.1% above weight of weight be preferred below 10%.In addition, well heat conductivity, higher durability if desired, then 0.5% above weight of weight is preferred especially below 9.5%.In addition, if further require high-durability, then 2% above weight of weight is preferred more below 8%.
Here, if Ib family metal does not reach at 85% o'clock of weight, the resistivity of internal electrode 12 will become greatly, and when laminate type piezoelectric element was moved continuously, internal electrode 12 can heating sometimes.In addition, in order to suppress 1b family metal in the interior metal 12 to piezoelectrics 11he migration, Ib family metal be weight 85% above weight be preferred below 99.999%.In addition, on the durability that improves laminate type piezoelectric element, 90% above weight of weight be preferred below 99.9%.In addition, higher if desired durability, 90.5% above weight of weight preferred especially below 99.5%.In addition, higher if desired durability, 92% above weight of weight be preferred more below 98%.
Represent that VIII family metal, the Ib family metal of the metal ingredient quality % in the above-mentioned internal electrode 12 can use analytical methods such as EPMA (Electron Probe Micro Analysis) method specific.
And the metal ingredient in the internal electrode 12 of the present invention, VIII family metal are more than at least a among Ni, Pt, Pd, Rh, Ir, Ru, the Os, and Ib family metal is to be preferred more than at least a among Cu, Ag, the Au.Because this is the outstanding metal ingredient of alloy powder synthetic technology medium quantity batch processing in recent years.
And the metal ingredient in the internal electrode 12, VIII family metal are more than at least a among Pt, the Pd, and Ib family metal is to be preferred more than at least a among Ag, the Au.In view of the above, just might form the internal electrode 12 that thermal endurance is outstanding, resistivity is little.
And, the metal ingredient in the internal electrode 12, the metal Ni of VIII family is preferred.In view of the above, just might form the outstanding internal electrode of thermal endurance 12.
And, the metal ingredient in the internal electrode 12, the metal Cu of Ib family is preferred.In view of the above, just might form the outstanding internal electrode of heat conductivity 12.
And in the internal electrode 12, it is preferred adding inorganic constituents with the metal ingredient thing.In view of the above, just might make internal electrode 12 and piezoelectrics 11 combination securely.In addition, above-mentioned inorganic constituents is by PbZrO
3-PbTiO
3The perofskite type oxide of forming is that principal component is preferred.
And piezoelectrics 11 are preferred with perofskite type oxide as principal component.This be because, for example, if by with barium titanate (BaTiO
3) for the formation such as Ca-Ti ore type piezoceramic material of representative, represent the piezoelectric strain constant d33 height of its piezoelectric property, displacement can be very big, and, also can burn till piezoelectrics 11 and internal electrode 12 simultaneously.As the piezoelectrics 11 of above-mentioned performance, with piezoelectric strain constant d33 than higher PbZrO
3-PbTiO
3The perofskite type oxide of forming is preferred as principal component.
And to be lower than 1000 ℃ be preferred to the firing temperature of piezoelectrics 11 in order to be higher than 900 ℃.This be because, if firing temperature is lower than 900 ℃, burn till deficiency because firing temperature is low, be difficult to produce careful piezoelectrics 11.In addition, if firing temperature surpasses 1000 ℃, the stress that shrinks deviations because of the contraction and the piezoelectrics 11 of internal electrode 12 when burning till is very big, might crack when the laminate type piezoelectric element Continuous Drive.
In addition, the deviation of the composition in the internal electrode 12 is to be preferred below 5% before and after burning till.This be because, if the deviation of the composition in the internal electrode 12 surpasses 5% before and after burning till, metal material in the internal electrode 12 will increase to the migration of piezoelectrics 11, and is flexible for what drive because of laminate type piezoelectric element, and might internal electrode 12 becoming can not servo-actuated.
Here, the deviation of the composition in the so-called internal electrode 12, expression is evaporated or is spread to piezoelectrics 11 by burning till, the rate of change of the composition variation of internal electrode 12 because of the element that constitutes internal electrode 12.
The laminate type piezoelectric element of present embodiment 2, respectively on two sides of laminated body, the internal electrode end, expose every one, the internal electrode end of not exposing the end is left from a side and is positioned at inside, but form groove towards being positioned at its inner end, the insulator that the Young's modulus of packing ratio piezoelectrics is low in its groove is preferred.Can relax such laminate type piezoelectric element because of the stress that displacement produced in driving because do like this,, also can suppress the heating of internal electrode 12 even make its Continuous Drive.
The manufacture method of laminate type piezoelectric element of the present invention then, is described.
Laminate type piezoelectric element of the present invention, at first, will be by PbZrO
3-PbTiO
3Adhesive, DBP (Dibutyl phthalate), DOP (ethyl phthalate) plasticizer of etc.ing that the standard of the piezoelectric ceramic of the perofskite type oxide that forms burns powder, acrylic compounds, is made up of organic polymers such as butyral classes mix and are made into slip, this slurry are produced the ceramic green sheet of formation piezoelectrics 11 by adhesive tape forming processes such as known scraping blade method, stack methods.
Then, in the metal dust of internal electrodes 12 such as formation silver-palladium, mixed add metal oxide, adhesive and plasticizer etc. such as silver oxide and produce conductive paste, and the thickness with 1～40 μ m prints on above-mentioned each raw cook surface by silk screen printing etc. with it.
And the raw cook that will print conductive paste in the above is lamination repeatedly, hereto laminated body with fixed temperature carry out producing laminated body 13 by burning till after adhesive breaks away from 900～1200 ℃.
At this moment, in the raw cook of inert layer 14 parts, add the metal dust that constitutes internal electrodes 12 such as silver-palladium, when the raw chip laminating of lamination inert layer 14 parts, the slip that metal dust by will constituting internal electrode such as silver-palladium and inorganic compound, adhesive, plasticizer form is printed on the raw cook, inert layer 14 and contraction behavior and the shrinkage of other parts when sintering are consistent, thereby can form careful laminated body.
Moreover laminated body 13 is not limited to the making by said method, as long as can produce a plurality of piezoelectrics 11 and a plurality of internal electrode 12 alternative stacked and the laminated body 13 that constitutes, and can by which type of manufacture method.
After this, the internal electrode 12 that exposes the internal electrode 12 of end in the side of laminate type piezoelectric element and do not expose the end alternately forms, form groove in the piezoelectrics part between internal electrode 12 that does not expose the end and outer electrode 15, in this groove, form than insulators such as also low resin of the Young's modulus of piezoelectrics 11 or rubber.Here, above-mentioned groove forms with the side in laminated body 13 such as inner cutter sweep.
From the electric conducting material that absorb to constitute outer electrode 15 angle because of the flexible stress that is produced of driver, the silver that Young's modulus is low, or be that the alloy of principal component is best with silver.
In glass powder, add adhesive and produce silver-colored glass conductive paste, and make it form sheet, the sheet that (solvent is dispersed) after the drying is controlled at 6～9g/cm
3Pure density in, and this sheet is transferred to the external electric pole-face of column laminated body 13, by with the temperature also higher than the softening point of glass, and with the following temperature of silver point (965 ℃), and with firing temperature (℃) temperature sintering less than 4/5, adopt silver-colored glass conductive paste to make the disappearance of dispersing of adhesive ingredients in the sheet of making, just can form the outer electrode of forming by the porous matter electric conductor of three-dimensional mesh configuration 15.
Moreover, the sintering temperature of above-mentioned silver-colored glass conductive paste, from forming neck effectively, it is connected with silver and internal electrode 12 diffusions in the silver-colored glass conductive paste, in addition, make the space in the outer electrode 15 effectively residual, and make outer electrode 15 see preferably 550～700 ℃ with the angle that column laminated body 13 lateral parts are connected.In addition, the softening point of glass ingredient in the silver-colored glass conductive paste, preferably 500～700 ℃.
When sintering temperature was higher than 700 ℃, the sintering of the silver powder of silver-colored glass conductive paste will too move ahead, and can not form the porous quality electric conductor of effective three-dimensional mesh configuration.That is, outer electrode 15 is too fine and closely woven, and its result might make the Young's modulus of outer electrode 15 too high, can not fully absorb the stress when driving and makes outer electrode 15 broken strings.Preferably, preferably carry out sintering with interior temperature with 1.2 times of glass softening points.
On the other hand, if when sintering temperature is lower than 550 ℃ since between the end of internal electrode 12 and outer electrode 15 fully diffusion connect, can not form neck, might when driving, between internal electrode 12 and outer electrode 15, cause spark.
Moreover the sheet thickness of silver-colored glass conductive paste is preferably than the thin thickness of piezoelectrics 11.And more preferably, from following the trail of the flexible angle of driver, less than 50 μ m for well.
Then, when the laminated body 13 that will form outer electrode 15 is soaked in silicone rubber solution, by silicone rubber solution is carried out vacuum suction, in the groove of laminated body 13, fill silicone rubber, after this from silicone rubber solution, pull laminated body 13 out, to the side SC rubber of laminated body 13.After this, inner that fill and by making groove in the above-mentioned silicone rubber sclerosis of the side of column laminated body 13 coating, just finished laminate type piezoelectric element of the present invention.
And, connect lead to outer electrode 15, between this lead-apply the direct voltage of 0.1～3kv/mm on to outer electrode 15, by processing that laminated body 13 is polarized, just finished the lamination-type piezoelectric actuator that adopts laminate type piezoelectric element of the present invention.Like this in the lamination-type piezoelectric actuator of making, if the voltage supply unit of lead with the outside is connected, apply voltage between lead and 15 pairs of internal electrodes 12 of outer electrode, each piezoelectrics 11 produces very big displacement because of inverse piezoelectric effect, and performance is for example as the function of spraying the automobile fuel jet of fueling to engine thus.
And externally on the outside of electrode 15, metallic mesh or net-shaped metal plate also can be formed by the conductivity auxiliary material that the conductivity sticker of being buried underground is formed.In this case, the electric current that the conductivity auxiliary material of setting up by the outside of electrode 15 externally have high input to driver, even can make its high-speed driving, but big electric current can flow to the conductivity auxiliary material, thereby can reduce the electric current that flows to outer electrode 15.Thus, can prevent outer electrode 15 caused local pyrexias, broken string, thereby can increase substantially durability.And, owing in the conductivity sticker, buried metallic mesh or net-shaped metal plate underground, so can prevent from above-mentioned conductivity sticker, to crack.
So-called metallic mesh is to enroll the material of metal wire, and so-called net-shaped metal plate makes the Web materials that forms the hole on metallic plate.
And the conductivity sticker that constitutes above-mentioned conductivity auxiliary material preferably is made up of the polyimide resin that silver powder is not disperseed.That is, disperse in the high polyimide resin of thermal endurance by making the low silver powder of resistivity, even use when high temperature, it is low and keep the conductivity auxiliary material of high adhesion strength also can to form resistance value.And, being more preferably, above-mentioned electroconductive particle is that aspheric particles such as sheet or needle-like are best.This is because by the shape of electroconductive particle being done the nonspherical particle of slabbing or needle-like etc., can consolidate the mutual winding between this electroconductive particle, thereby can further improve the branch shearing stress of this conductivity sticker.
Laminate type piezoelectric element of the present invention is not limited to above execution mode 2, can carry out various changes in the scope that does not surmount the invention main idea.
In addition, above-mentioned example to the outer electrode 15 that forms on the relative side of laminated body 13 is illustrated, but the present invention also can for example form pair of external electrodes in adjacent side.
Fig. 8 is the thing of expression injection apparatus of the present invention, at an end of accommodating container 31 spray-hole 33 is set, and in addition in accommodating container 31, but contains the needle valve 35 of switch spray-hole 33.
The fuel passage 37 that can be communicated with is set on spray-hole 33, and this fuel passage 37 is connected with the fuel supply source of outside, supplies with certain fuel under high pressure on fuel passage 37 at ordinary times.Therefore, when needle valve 35 was opened spray-hole 33, the fuel of fueling path 37 just sprayed in the no illustrated fuel chambers of internal combustion machine with certain high pressure and forms.
In addition, the upper end diameter of needle valve 35 is very big, cylinder 39 that forms on accommodating container 31 and piston 41 slidably.Then, in accommodating container 31, taken in above-mentioned piezoelectric actuator 43.
Such injection apparatus, when extending when applying voltage to piezoelectric actuator 43, piston 41 is pushed, and needle valve 35 is just closed spray-hole 33, stops the supply of fuel.In addition, when stopping to apply voltage, piezoelectric actuator 43 just shrinks, and disk spring 45 pushes back piston 41, and spray-hole 33 is communicated with fuel passage 37 and carries out the injection of fuel and form.
In addition, Fig. 8 is the thing of relevant laminate type piezoelectric element and injection apparatus, and the present invention is not limited to formation shown in Figure 8.Undoubtedly applicable to for example, fuel injection device at car engine, liquid injection apparatus such as ink-jet, determine that precision positioning device such as Optical devices or antihunting device etc. go up the driving element of assembling, or at the burning pressure sensor, knock transducer, acceleration transducer, load sensor, ultrasonic sensor, the pressure-sensitive transducer, angular-rate sensors etc. are gone up the sensor element of assembling, and at piezoelectric gyroscope, Piezoelectric switches, piezoelectric transformer, piezoelectricity circuit breakers etc. are gone up the circuit element of assembling, even in addition beyond these represented things, so long as use the element of piezoelectric property, just applicable.
The piezo-electric type electronic unit of embodiments of the present invention 3 is the lamination-type piezoelectric actuator that has with execution mode 1 identical formation, and is variant with the part of execution mode 1 production process.
Moreover Fig. 9 has represented to amplify the part of the lamination-type piezoelectric actuator section of execution mode 3, and the key element identical with Fig. 1 adopts identical symbolic representation.
Here, the thickness of piezoelectric body layer 1, the distance between the internal electrode 2 just from miniaturization and apply the angle of high electric field, preferably is set at less than 200 μ m, more preferably less than 150 μ m.On the other hand, the thickness of piezoelectric body layer 1 improves the angle of driven nature from shortening the electric energy saturation time that applies to piezoelectric body layer 1, preferably be set at greater than 50 μ m, more preferably greater than 70 μ m.That is, the lamination number is for being preferred greater than 200 layers.Laminate type piezoelectric element is after applying voltage, adopt the method that increases the lamination number in order to obtain big displacement, if but increase the lamination number, the thickness of the piezoelectric body layer 1 in the laminated piezoelectric body 3 is too thick just can not to make driver miniaturization, dwarf formsization, on the other hand, if the thickness of the piezoelectric body layer 1 in the laminated piezoelectric body 3 is too thin, because of above-mentioned reason insulation punctures easily, so above-mentioned scope is preferred.
Moreover, the crystal grain of the piezoelectric body layer 1 of formation present embodiment 3, its average grain diameter is preferred less than 5 μ m, and is preferred especially less than 3 μ m.
And the laminate type piezoelectric element of present embodiment 1 by making of manufacture method described later, is 5% with interior a bit very important with the rate of change that constitutes degree of orientation f crystal grain, before and after driving of piezoelectric body layer 1.Particularly, in order to carry out 10
9Inferior above Continuous Drive is suppressed at 3% with interior preferred especially with the rate of change of degree of orientation f.Under the condition of load 150kgf, 150 ℃ of temperature, frequency 50Hz,, laminate type piezoelectric element can carry out 10 by being applicable to
9Repeat to drive injection apparatus etc. more than inferior, can obtain the injection apparatus of high reliability.
To this,, the rate of change of the degree of orientation f crystal grain of formation piezoelectric body layer 1, that drive front and back also lacks if, just not only can not obtaining piezoelectric property the same with Continuous Drive but also durable time greater than 5%.
Figure 10 is the process flow chart that laminate type piezoelectric element of the present invention is made in expression.Below, be described in detail its manufacture method for lamination-type piezoelectric actuator as the laminate type piezoelectric element typical example of present embodiment 3.
The manufacture method of the laminate type piezoelectric element of present embodiment 3, identical with execution mode 1, for example, make the ceramic green sheet 21 (Figure 10 A) of thickness 50～250 μ m.
In the manufacture method of present embodiment 3, burn the preferable range of average grain diameter of piezoelectricity powder of powder and the preferable range of raw cook 21 thickness as the standard of piezoelectric body layer 1, identical with execution mode 1.
Then, identical with execution mode 1, on the single face of the raw cook of getting through by institute's sizing 21, form conductive pattern 22.In this case, identical with execution mode 2, be preferably in the conductor paste ceramic powders is mixed as common material.
Then, identical with execution mode 1, make laminated piezoelectric organizator 23, with the laminated piezoelectric organizator by after fixed size cuts, in atmosphere, carry out after the degreasing, formally burn till and produce stacked piezoelectric body 3.
Moreover, in present embodiment 3, burn till, for example, can improve the Ag ratio in the internal electrode 2, in order to reduce cost, be lower than 1000 ℃, particularly be lower than 980 ℃ and carry out better.
Then, identical with execution mode 1, on the end face of laminated piezoelectric body 3, coat the outer electrode slurry that contains Ag-glass, and heat-treat with 500～900 ℃ temperature, form outer electrode 4 shown in Figure 10.In this case, in heat treatment step,, identical with execution mode 1 from the preferable range of the cooling rate of heat treated maximum temperature.
As above laminate type piezoelectric element, according to the operation shown in Figure 11 processing that polarizes with made.
Specifically, soak in temperature being warmed to 100～400 ℃ oil-bath exactly, the pair of external electrodes 4 that forms on this element applies the direct voltage of 0.1～3kv/mm, and the crystal grain that constitutes piezoelectric body layer is fully polarized.
Make after its polarization, under with the state of the voltage that keeps applying like this below Curie point, cool to room temperature.Then, after cool to room temperature, reduce electric field.Handle by such polarization, finish the laminate type piezoelectric element of execution mode 3.
The laminate type piezoelectric element of present embodiment 3, by above operation polarize handle very important.
Usually, for example,, when burning till, will spread to the piezoelectric body layer direction if contain Ag at internal electrode 2.If Ag diffuses through the pottery diffusion mutually with piezoelectric body layer, in pottery, will form oxygen defect.Oxygen defect becomes oxygen cavity ion when Continuous Drive, the direction of displacement of B side (Zr, the Ti) ion that constitutes piezoelectric body layer is exerted one's influence, thereby the degree of orientation of pottery is changed after long-time.To this present invention, owing to polarize fully, so the degree of orientation that can suppress pottery is in long-time later variation with above-mentioned condition.
Here, among the c/a as the ratio of the lattice constant of the piezoelectrics that constitute piezoelectric body layer, the rate of change before and after the polarization is preferably less than 0.5%.If the rate of change of c/a is greater than 0.5%, the stress that produces during because of polarization will be peeled off between internal electrode 2 and piezoelectric body layer 1.Present embodiment 3, for prevent effectively because of when polarization stress produced peels off, the rate of change of c/a is better less than 0.2%.Here, the c/a of the ratio of lattice constant asks lattice constant a from the XRD diffraction pattern by the peak value of the indices of crystallographic plane (200), similarly asks lattice constant c from the peak value of the indices of crystallographic plane (002), asks c/a by these values.
Moreover the manufacture method of the laminate type piezoelectric element of present embodiment 3 is applicable to laminate type electronic components such as lamination-type piezoelectric transformer, lamination-type capacitor, lamination-type piezoelectric actuators.Particularly, in the lamination-type piezoelectric actuator of high electric field Continuous Drive, employing piezoelectric ceramic, the manufacture method of laminate type piezoelectric element of the present invention is the most suitable.Moreover, drive experimental condition, be preferably under the condition with load 150kgf, 150 ℃ of temperature, frequency 50Hz and repeat 10
9More than inferior.
Adopt laminate type piezoelectric element, can be implemented in identical injection apparatus illustrated in the execution mode 2 as the execution mode 3 of above formation.
Above execution mode 3 will be illustrated with the example that Ag-Pd constitutes internal electrode 2, but the present invention is not limited, and can adopt various materials to constitute internal electrodes 2.
Yet, the metal ingredient that constitutes internal electrode 2 be preferably VIII family metal, Ib family intrametallic any one or the both sides of VIII family metal and Ib family metal as principal component.Particularly, when the amount of VIII family metal is the amount of M1%, the Ib family metal of quality when being the M2% of quality, preferably with composition than being set at the relation that satisfies 0.001≤M1≤15,85≤M2≤99.999, M1+M2=100 quality %.Particularly, be preferably 3≤M1≤8,92≤M2≤97.
Here, VIII family metal is at least a among Ni, Pt, Pd, Rh, Ir, Ru, the Os, Ib family metal is at least a among Cu, Ag, the Au, at least a among the metal Pt of VIII family, the Pd particularly, Ib family metal is at least a among Ag, the Au, and VIII family metal is Ni, or Ib family metal is that Cu is better.
On the other hand, the thickness of internal electrode of the present invention is preferred less than 5 μ m, more preferably is set at less than 4 μ m.
In addition, internal electrode 2 of the present invention contains inorganic constituents, and the composition of the composition of its inorganic constituents and piezoelectric body layer 1 is identical to be preferred, and the average grain diameter of this inorganic constituents, is preferred for a short time than the average grain diameter of piezoelectric body layer 1.
Then, on the one side of this ceramic green sheet 21, as shown in Figure 2, the conductive paste that contains silver-palladium, solvent that will become internal electrode 2 prints by the thickness of silk screen print method with 4 μ m, forms inner conductor pattern 22.
Then, will form 30 of ceramic green sheet 21 laminations of inner conductor pattern 22, in the top and bottom of this laminated body, 5 of each laminations are not coated with the ceramic green sheet 21 of conductive paste, and produce the lamination organizator 23 of structure as shown in Figure 3.
Then, this lamination organizator 23 is configured in the metal die, heats the pressurization that an end carries out 100MPa by hydrostatic pressing with 90 ℃ of one end and make it integrated.
Be cut into after 10mm * 10mm size, break away from, and in 1130 ℃, carry out 2 hours formally burn till, thereby obtain column laminated body 3 with 800 ℃ of adhesives that carried out 10 hours.
After this, in the relative side of active portion, coating with silver is the Ag glass cream (glasspaste) of principal component,, heat-treats respectively by the cooling rate shown in the table 1 and to form outer electrode 4 after 1 hour with 750 ℃ of heating.
After this, apply 15 fens kinds of DC electric field of 3kv/mm, polarize and handle and produce laminate type piezoelectric element by outer electrode 4 to positive pole and negative pole.The c/a rate of change of the ratio of lattice constant at this moment is as shown in table 1.
Table 1.
| No | Chilling temperature (℃ branch) | C/a rate of change (%) | Interfacial gap μ m | The interval is less than the ratio % of 2 μ m | The generation of splitting |
| *1-1 | 150 (Curie temperature/2) | 0.60 | 2.8 | 5 | Have |
| 1-2 | 100 (Curie temperature/3) | 0.45 | 1.6 | 52 | Do not have |
| 1-3 | 50 (Curie temperature/6) | 0.20 | 1.0 | 71 | Do not have |
| 1-4 | 10 (Curie temperature/30) | 0.05 | 0.3 | 86 | Do not have |
| 1-5 | 5 (Curie temperature/60) | 0.05 | 0.3 | 98 | Do not have |
Shown in this table 1, the test portion of No.1-2～1-5 of the present invention, internal electrode and piezoelectric body layer, the relative active region of two adjacent internal electrodes 50% with top, at interval to approaching, do not find the generation of interface splitting less than 2 μ m yet.To this, cooling rate is extraneous test portion No.1-1 of the present invention, because cooling rate is fast, interfacial gap is 2.8 very big μ m, in addition, since little less than the part of 2 μ m to 5%, confirmed the generation of splitting with binocular microscope inspection outward appearance.
Then, on the one side of ceramic green sheet, form conductive paste with the thickness of 3 μ m, its sheet with 300 laminations, and is burnt till by silk screen print method.Burn till, after 800 ℃ of maintenances, burn till with 1000 ℃ again.Here, conductive paste, by making to silver-palladium alloy interpolation silver oxide and adhesive, the ratio of components of silver-palladium alloy can be set arbitrarily.
After burning till, forming the degree of depth by cutter sweep at the internal electrode end of laminated body side interlayer is that 50 μ m, width are the groove of 50 μ m.
Then, to the flake silver powder of average grain diameter 2 μ m not with 90% volume, with the remainder average grain diameter be 2 μ m be principal component with silicon, softening point is that amorphous glass powder of 640 ℃ is with the mixture of 10% volume, 100 Quality Mgmt Dept of the total weight of relative silver powder of adhesive and glass powder are added 8 Quality Mgmt Dept, and fully mix and produce silver-colored glass conductive paste.The silver-colored glass conductive paste of making is like this formed by silk screen printing on stripping film, after the drying, peel, thereby obtain the sheet of silver-colored glass conductive paste from stripping film.Pure density to this sheet is measured with Archimedes's method, is 6.5g/cm
3
And, the sheet of above-mentioned silver-colored glass cream is transferred to the surface of the outer electrode 15 of laminated body 13, with 650 ℃ of sintering that carry out 30 minutes, thereby form the outer electrode of forming by the porous matter electric conductor of three-dimensional mesh configuration 15.Moreover at this moment the voidage of outer electrode 15 adopts the image analysis apparatus of the section photo of outer electrode 15 to be measured as 40%.
After this, connect leads to outer electrode 15, the 15 fens kinds of DC electric field that apply 3kv/mm between lead to the outer electrode 15 of positive pole and negative pole processing that polarizes, thus produce the lamination-type piezoelectric actuator of employing laminate type piezoelectric element shown in Figure 1.
Resulting laminate type piezoelectric element is applied the result of the direct voltage of 170V, obtain displacement to stack direction 45 μ m.And, to this laminate type piezoelectric element at ambient temperature with the frequency of 150Hz apply 0～+ alternating voltage of 170V, drive test.
Then, for the laminate type piezoelectric element of made tabulation 2,3, will carry out 1 * 10
9Laminate type piezoelectric element after the inferior driving is processed into 3mm * 4mm * 36mm, with 4 bendings of JIS R1601, measures bending strength.At this moment, the electrode surface of internal electrode 12 is to the place vertical substantially than length direction of test film, and that test film has all been confirmed the destruction on the interface of internal electrode 12 and piezoelectrics 11.
And, for the test portion shown in the table 2, by SEM average crystallite particle diameter and its average crystallite particle diameter with exterior domain of the piezoelectrics 11 of contact internal electrode 12 are measured respectively, measure relation with bending strength.As method of measurement, draw straight line from available image facing to the image of the piezoelectrics particle of internal electrode with SEM, anywhere, select totally 50 particles, with the mean value of the straight line crosscut length of each particle as the average crystallite particle diameter.
And straight line is being drawn facing to the arbitrary image place beyond the piezoelectrics of internal electrode in so-called other zone, selects to amount to 50 particles, with the mean value of the straight line crosscut length of each particle as the average crystallite particle diameter.
Moreover minimum knot crystal grain footpath is from the crystal grain of measuring the identical image of average crystallite particle diameter, as the particle diameter of minimum.
In order to compare, the average crystallite particle diameter of piezoelectrics 11 that the manufacture method by in the past will contact internal electrode 12 is identical with other part, or the relation of the bending strength more than it time is also put down in writing.
In addition, for the test portion shown in the table 3, by SEM the minimum knot crystal grain footpath of the piezoelectrics 11 of contact internal electrode 12 and the minimum knot crystal grain footpath and the maximum crystallization particle diameter in maximum crystallization particle diameter and the zone beyond it are measured respectively, and to measuring with the relation of bending strength.Method of measurement adopts the method identical with table 2.In order to compare, represented the minimum knot crystal grain footpath of piezoelectrics 11 of contact internal electrode 12 and maximum crystallization particle diameter with its beyond the zone minimum knot crystal grain directly and maximum crystallization particle diameter identical or more than it the time and the relation of bending strength substantially.Its result is shown in following table 2,3.
Table 2.
| No | Average crystallite particle diameter 1 (μ m) | Average crystallite particle diameter 2 (μ m) | Bending strength (MPa) |
| *2-1 | 0.4 | 0.4 | 34.3 |
| 2-2 | 1.0 | 0.8 | 84.6 |
| 2-3 | 1.9 | 1.7 | 90.2 |
| 2-4 | 2.7 | 2.4 | 92.4 |
| 2-5 | 3.8 | 3.5 | 103.6 |
| 2-6 | 5.7 | 5.2 | 99.6 |
| 2-7 | 8.0 | 7.9 | 83.0 |
| *2-8 | 9.2 | 9.8 | 40.2 |
Average crystallite particle diameter 1 in the table 2 is illustrated near the average crystallite particle diameter (μ m) the internal electrode in the piezoelectrics, and average crystallite particle diameter 2 is meant the average crystallite particle diameter (μ m) that removes near the part the internal electrode in piezoelectrics.
Table 3.
| No | Maximum crystallization particle diameter 1 (μ m) | Minimum knot crystal grain footpath 1 (μ m) | Maximum crystallization particle diameter 2 (μ m) | Minimum knot crystal grain footpath 2 (μ m) | Bending strength MPa |
| *2-9 | 1.2 | 0.1 | 1.3 | 0.2 | 34.3 |
| 2-10 | 2.4 | 0.5 | 2.3 | 0.3 | 84.6 |
| 2-11 | 2.6 | 1.0 | 2.8 | 0.3 | 90.2 |
| 2-12 | 3.1 | 2.7 | 3.0 | 0.3 | 92.4 |
| 2-13 | 4.5 | 3.8 | 4.6 | 0.3 | 103.6 |
| 2-14 | 6.2 | 5.0 | 6.8 | 0.2 | 99.6 |
| 2-15 | 8.4 | 4.6 | 8.1 | 0.4 | 83.0 |
| *2-16 | 10.1 | 5.0 | 11.2 | 5.2 | 40.2 |
Maximum crystallization particle diameter 1 in the table 3 is illustrated near the maximum crystallization particle diameter (μ m) of internal electrode in the piezoelectrics, and minimum knot crystal grain footpath 1 is illustrated near the minimum knot crystal grain footpath (μ m) of internal electrode in the piezoelectrics.
In addition, the maximum crystallization particle diameter 2 in the table 3 is illustrated in the interior average crystallite particle diameter (μ m) except that near the part the internal electrode of piezoelectrics, and minimum knot crystal grain footpath 2 is illustrated in the interior minimum knot crystal grain footpath (μ m) except that near the part of internal electrode of piezoelectrics.
According to table 2, as (test portion .No.2-1 when little or identical facing to the average crystallite particle diameter in the average crystallite size ratio of the piezoelectrics 11 of internal electrode 12 zone beyond it, 2-8), just can not obtain sufficient bending strength, but the average crystallite particle diameter that faces toward the piezoelectrics 11 of internal electrode 11 passes through big (the test portion No.2-2～2-7), can confirm the raising of bending strength of average crystallite particle diameter than the zone beyond it.
In addition, according to table 3, any test portion is facing to the maximum crystallization particle diameter of the piezoelectrics 11 of internal electrode 12, compare with the maximum crystallization particle diameter in zone beyond it also identical substantially, or its above size.; if between minimum knot crystal grain footpath, it is compared; the minimum knot crystal grain footpath that faces toward the piezoelectrics 11 of internal electrode 12; when than the minimum knot crystal grain footpath in the zone beyond it hour; can not obtain sufficient bending strength (test portion 2-9,2-16), to this by will be facing to the minimum knot crystal grain footpath of the piezoelectrics 11 of internal electrode 12; make greatlyyer, just can confirm raising (the test portion 2-10～2-14) of bending strength than the minimum knot crystal grain footpath in the zone beyond it.
In addition, according to table 3,, can confirm the raising of bending strength by will directly making greater than 0.5 μ m less than 5 μ m facing to the minimum knot crystal grain of the piezoelectrics 11 of internal electrode 12.
In a word, from the interfacial failure of which test film at internal electrode 12 and piezoelectrics 11, by will be facing to crystallization particle diameter (the average crystallite particle diameter of the piezoelectrics 11 of internal electrode 12, minimum knot crystal grain footpath) makes crystallization particle diameter (average crystallite particle diameter than the zone beyond it, minimum knot crystal grain footpath) big, can confirm that the intensity that is adjacent at internal electrode 12 and piezoelectrics 11 interfaces improves.
Then, as the embodiment 3 relevant with execution mode 2, making is made up of the material of different internal electrode 12 and the laminate type piezoelectric element that forms, minimum knot crystal grain footpath and maximum crystallization particle diameter in minimum knot crystal grain footpath and the maximum crystallization particle diameter and the zone beyond it of the piezoelectrics of measuring contact electrode under the condition identical, and the relation of evaluation and bending strength with embodiment 2.Its result is shown in surface 4.Moreover, the rate of change of the displacement of each test portion is also measured in the lump.As rate of change, the laminate type piezoelectric element of each test portion reaches and drives number of times 1 * 10
9The time displacement (μ m), compare with the displacement (μ m) of the laminate type piezoelectric element A-stage of beginning before the Continuous Drive, investigated the aging degree of displacement and laminate type piezoelectric element.Its result is as shown in table 4.
Table 4 (1)
| No | The amount of Pd (quality %) | The amount of Pt (quality %) | The amount of Ag (quality %) | Other internal electrode metals (quality %) |
| 3-17 | 0 | 0 | 100 | 0 |
| 3-18 | 0.001 | 0 | 99.999 | 0 |
| 3-19 | 0.01 | 0 | 99.99 | 0 |
| 3-20 | 0.1 | 0 | 99.9 | 0 |
| 3-21 | 0.5 | 0 | 99.5 | 0 |
| 3-22 | 1 | 0 | 99 | 0 |
| 3-23 | 2 | 0 | 98 | 0 |
| 3-24 | 4 | 1 | 95 | 0 |
| 3-25 | 5 | 0 | 95 | 0 |
| 3-26 | 8 | 0 | 92 | 0 |
| 3-27 | 9 | 0 | 91 | 0 |
| 3-28 | 9.5 | 0 | 90.5 | 0 |
| 3-29 | 10 | 0 | 90 | 0 |
| 3-30 | 15 | 0 | 85 | 0 |
| 3-31 | 20 | 0 | 80 | 0 |
| 3-32 | 30 | 0 | 70 | 0 |
| 3-33 | 0 | 0 | 0 | Cu100％ |
| 3-34 | 0.1 | 0 | 0 | Cu99.9％ |
| 3-35 | 0 | 0 | 0 | Ni100％ |
Table 4 (2)
| No | Average grain diameter 1 (μ m) | Average grain diameter 2 (μ m) | Displacement rate of change (%) | Bending strength (MPa) |
| 3-17 | Destruction because of moving in the driving | - | ||
| 3-18 | 4.2 | 3.5 | 0.7 | 96.8 |
| 3-19 | 4.2 | 3.6 | 0.7 | 97.1 |
| 3-20 | 4.1 | 3.6 | 0.4 | 98.0 |
| 3-21 | 4.0 | 3.6 | 0.2 | 99.8 |
| 3-22 | 4.0 | 3.6 | 0.2 | 100.4 |
| 3-23 | 3.9 | 3.6 | 0 | 102.5 |
| 3-24 | 3.8 | 3.5 | 0 | 105.1 |
| 3-25 | 3.8 | 3.5 | 0 | 107.2 |
| 3-26 | 3.7 | 3.4 | 0 | 104.2 |
| 3-27 | 3.6 | 3.4 | 0.2 | 100.7 |
| 3-28 | 3.5 | 3.3 | 0.2 | 99.2 |
| 3-29 | 3.4 | 3.3 | 0.4 | 98.2 |
| 3-30 | 3.3 | 3.2 | 0.7 | 97.2 |
| 3-31 | 2.7 | 2.5 | 0.9 | 90.5 |
| 3-32 | 2.5 | 2.3 | 0.9 | 90.3 |
| 3-33 | 3.8 | 3.5 | 0.2 | 102.1 |
| 3-34 | 3.8 | 3.5 | 0 | 103.1 |
| 3-35 | 3.7 | 3.4 | 0.4 | 100.9 |
In addition, the displacement that the displacement rate of change in the table 4 is expression carries out after the Continuous Drive test the displacement of A-stage changes.
According to table 4, if the internal electrode 12 of test portion No.3-17 was made silver-colored 100% o'clock, because of silver migration, laminate type piezoelectric element damages and can not Continuous Drive.In addition, except that test portion No.3-17, form greatly facing to the average grain diameter of the piezoelectrics 11 of internal electrode 12 average crystallite particle diameter than the piezoelectrics 11 in the zone beyond it, but test portion No.3-31, in the metal ingredient thing of 3-32 in internal electrode 12, account for 15% of weight, or the content of Ib family metal does not reach and accounts for 85% of weight because the content of VIII family metal surpasses, because of Continuous Drive wears out, descend so just understand the durability of lamination-type piezoelectric actuator.Therefore, also just understand reduction for the bending strength of this situation.
Relative with it, No.3-18～3-30 and 33～35, facing to the average crystallite grain the earth formation of the average grain diameter of the piezoelectrics 11 of internal electrode 12 than the zone beyond it, and, when the amount of the metal ingredient thing VIII family metal in the internal electrode 12 is made mass M 1%, when the amount of Ib family metal is made mass M 2%, owing to will satisfy 0≤M1≤15,85≤M2≤100, the metal ingredient thing of the quality % of M1+M2=100 is as principal component, so can obtain sufficient bending strength also can reduce internal electrode 12 in the being adjacent to property that improves internal electrode 12 and piezoelectrics 11 resistivity, even Continuous Drive also can suppress the heat that internal electrode 12 produces, just understood so can produce the stable lamination-type driver of element displacement.
Moreover the present invention is not restricted to the described embodiments, and all it doesn't matter to carry out various changes in the scope that does not exceed main idea of the present invention.
Will be by lead zirconate titanate Pb (Zr, Ti) O
3300 ℃ of Curie temperature that form, the piezoelectricity powder of particle diameter 0.7 μ m, the organic bond that is formed by butyral resin, mixed and produce slip with plasticizer, by the slurry molding casting, making thickness is the raw cook of 150 μ m.
On face of this raw cook, as shown in Figure 2, print by the thickness of silk screen print method by decided metal dust, organic resin of forming and the conductive paste that contains solvent with 4 μ m with the Ag-Pd composition that becomes internal electrode, form conductive pattern.Then, with having formed 30 of the raw chip laminatings of conductive pattern, in the top and bottom of this laminated body, 5 raw cooks that are not coated with conductive paste of lamination are produced the lamination organizator of structure as shown in Figure 2 respectively.
Then, it is configured in the metal die and heats the pressurization that an end carries out 100MPa by hydrostatic pressing with 90 ℃ of one end and make it integrated.
After its size with 10mm * 10mm cut, break away from, and in 1130 ℃, carry out 2 hours formally burn till, and obtain laminated piezoelectric body with 800 ℃ of adhesives that carried out 10 hours.The piezoelectric body layer thickness that constitutes the laminated piezoelectric body of making like this is 120 μ m, and internal electrode thickness is 3 μ m.The cooling Curie temperature that burns till carries out with the speed of t/3 (℃/minute) from maximum temperature during as t.
After this, facing on the side of active portion, coating with silver is the Ag glass cream of principal component, carry out 1 hour heating with 750 ℃ again after, form outer electrode by finish each heat treatment with the cooling rate shown in the table 5.
After this, temperature is set at 400 ℃ soaks in the oil-bath of heating, and the pair of external electrodes of this element is applied the direct voltage 1 hour of 3kv/mm, after the crystal grain that constitutes piezoelectric body layer is fully polarized, by with the state that keeps applying voltage like this below Curie point, cool to room temperature and produce laminate type piezoelectric element.In addition, the degree of orientation of crystal grain carries out 10 after polarization at once
9Obtain by X-ray diffraction method after the inferior driving test.At this moment the rate of change of the c/a of the ratio of lattice constant is as shown in table 5.Evaluation to the piezoelectricity electrostriction constant of actual effect, on the vibration isolators fixing laminate type piezoelectric element test portion is being applied giving under the load condition of 150kgf to stack direction, apply the voltage of 0～200V, measure the variable quantity of the total length of laminate type piezoelectric element test portion at this moment, by with the lamination number and apply voltage and calculate divided by this variable quantity.Curie temperature is obtained with the temperature characterisitic of measuring piezoelectric ceramic electric capacity.The high temperature groove is adopted in the high temperature long duration test, under the state that applies the 150kgf load, carries out 10 with the condition of 150 ℃ of temperature, frequency 50Hz
9Repeating till inferior drives.
On the other hand, with above-mentioned laminate type piezoelectric element, as the comparative example of handling the element of making through polarization in the past.Crystal grain diameter is obtained by electron microscope observation.
Table 5.
| No | The composition of internal electrode | Polarization condition | Average grain diameter μ m | Degree of orientation rate of change (%) | Actual effect piezoelectricity electrostriction constant d 33pm/V | Curie temperature ℃ | High-temperature test 10 19Inferior |
| *4-1 | 95/5 | 2 | 2.5 | 7 | 880 | 331 | ○ |
| 4-2 | 95/5 | 1 | 2.0 | 3 | 870 | 330 | ◎ |
| 4-3 | 95/5 | 1 | 2.5 | 4 | 880 | 330 | ◎ |
| 4-4 | 95/5 | 1 | 3.0 | 5 | 890 | 330 | ◎ |
| 4-5 | 85/15 | 1 | 2.5 | 4 | 910 | 330 | ◎ |
| 4-6 | 90/10 | 1 | 2.5 | 4 | 900 | 331 | ◎ |
From this table 5, carrying out polarization of the present invention handles, constitute piezoelectric body layer crystal grain, as the rate of change of the degree of orientation before and after driving 5% with interior test portion No.4-2～4-6, in the driving experimental condition of invention, the displacement after the Continuous Drive with 10% with interior also be good result.
To this, the rate of change of the degree of orientation is than 5% big test portion No.4-1 before and after driving, and it is 15% that the displacement after the Continuous Drive surpasses 10%.
By the present invention, the laminate type electronic component and the manufacture method thereof that can suppress the splitting between ceramic layer and the internal electrode can be provided, and laminate type piezoelectric element and the injection apparatus with outstanding durability can be provided.
Claims (25)
1. a laminate type electronic component is characterized in that,
Possess: by piezoelectric body layer with the internal electrode alternative stacked and laminated body that constitutes and the pair of external electrodes that on two relative sides of this laminated body, forms,
Described internal electrode is made of first internal electrode and second internal electrode, wherein, the side side of described first internal electrode in described two sides, be connected with the described outer electrode that on this side, forms, described second internal electrode is between described first internal electrode and in the opposing party side, be connected with the described outer electrode that on this side, forms
Described internal electrode and described piezoelectric body layer with in the part more than 50% of described first internal electrode and the opposed facing active region of described second internal electrode, become the following mode of 2 μ m at interval near also overlapping.
2. laminate type electronic component as claimed in claim 1 is characterized in that: the rate of change of the degree of orientation that constitutes the crystal grain of described piezoelectric body layer is in 5%.
3. laminate type electronic component as claimed in claim 2 is characterized in that: the average grain diameter of the crystal grain of described piezoelectric body layer is below the 5 μ m.
4. laminate type electronic component as claimed in claim 3 is characterized in that: the thickness of piezoelectric body layer is below the 200 μ m.
5. laminate type electronic component as claimed in claim 1 is characterized in that: the thickness of described internal electrode is below the 5 μ m.
6. laminate type electronic component as claimed in claim 1 is characterized in that: in described internal electrode, contain with as the different inorganic constituents of the metal of its principal component, the average grain diameter of this inorganic constituents is littler than the average grain diameter of the crystal grain of described piezoelectric body layer.
7. the manufacture method of a laminate type electronic component is characterized in that, comprising:
Making is by ceramic layer and internal electrode alternative stacked and the operation of the column laminated body that constitutes;
This column laminated body is processed into the operation of desirable size;
The operation that this column laminated body is heat-treated;
Operation at this column laminated body side coating conductive paste;
This conductive paste is heat-treated, make with described internal electrode with operation every the mutual pair of external electrodes that is connected of mode of one deck;
Described outer electrode is applied voltage, so that become the operation that the mode below 0.5% polarizes and handles as the rate of change of the c/a of the ratio of lattice constant.
8. the manufacture method of laminate type electronic component as claimed in claim 7, it is characterized in that: in the operation that described conductive paste is heat-treated, the cooling rate that begins from heat treated maximum temperature is below the t/3 (℃/minute), wherein, t (℃) expression described ceramic layer Curie temperature.
9. the manufacture method of laminate type electronic component as claimed in claim 7, it is characterized in that: in the operation that described conductive paste is heat-treated, when heat treatment is cooled off, when the Curie temperature with described ceramic layer be made as t (℃) situation under, be below the t/3 (℃/minute) in the cooling rate of the temperature province of 1.2t～0.8t.
10. laminate type piezoelectric element, comprise by piezoelectrics and internal electrode alternative stacked and the laminated body that constitutes, it is characterized in that: the average crystallite particle diameter of the part of the described internal electrode of contact of described piezoelectrics is bigger than the average crystallite particle diameter of the position beyond it.
11. laminate type piezoelectric element, comprise by piezoelectrics and internal electrode alternative stacked and the laminated body that constitutes, it is characterized in that: the minimum knot crystal grain footpath of the part of the described internal electrode of contact of described piezoelectrics, bigger than the minimum knot crystal grain footpath of the position beyond it.
12. laminate type piezoelectric element as claimed in claim 10 is characterized in that: the minimum knot crystal grain of piezoelectrics that contacts the part of described internal electrode directly is below the above 5 μ m of 0.5 μ m.
13. laminate type piezoelectric element as claimed in claim 10 is characterized in that: described internal electrode principal component is VIII family metal and/or Ib family metal.
14. laminate type piezoelectric element as claimed in claim 13, it is characterized in that: described internal electrode contains VIII family metal and Ib family metal, when the amount that is made as M1 (quality %), Ib family metal when the amount with VIII family metal is made as M2 (quality %), satisfies the mode of 0＜M1≤15,85≤M2＜100, M1+M2=100 with its ratio of components and set.
15. laminate type piezoelectric element as claimed in claim 14, it is characterized in that: described VIII family metal is to constitute by being selected from least a above in the group that constitutes with Ni, Pt, Pd, Rh, Ir, Ru, Os, and Ib family metal is to constitute by being selected from least a above in the group that constitutes with Cu, Ag, Au.
16. laminate type piezoelectric element as claimed in claim 15 is characterized in that: described VIII family metal is more than at least a among Pt, the Pd, and Ib family metal is more than at least a among Ag, the Au.
17. laminate type piezoelectric element as claimed in claim 15 is characterized in that: described VIII family metal is Ni.
18. laminate type piezoelectric element as claimed in claim 15 is characterized in that: described Ib family metal is Cu.
19. laminate type piezoelectric element as claimed in claim 13 is characterized in that: described internal electrode also contains inorganic compositions except that described principal component.
20. laminate type piezoelectric element as claimed in claim 19 is characterized in that: described inorganic compositions will be by PbZrO
3-PbTiO
3The perofskite type oxide that constitutes is as principal component.
21. laminate type piezoelectric element as claimed in claim 10 is characterized in that: described piezoelectrics with perofskite type oxide as principal component.
22. laminate type piezoelectric element as claimed in claim 21 is characterized in that: described piezoelectrics will be by PbZrO
3-PbTiO
3The perofskite type oxide that constitutes is as principal component.
23. laminate type piezoelectric element as claimed in claim 10 is characterized in that: the firing temperature of described laminated body is more than 900 ℃ below 1000 ℃.
24. laminate type piezoelectric element as claimed in claim 10 is characterized in that: the deviation of the composition in the described internal electrode is below 5% before and after burning till.
25. laminate type piezoelectric element as claimed in claim 10 is characterized in that:
Described internal electrode is, first internal electrode and second internal electrode that comprise alternative stacked, and the end of on first side of described laminated body, exposing described first internal electrode, and on the other hand, separate from described first side end of second internal electrode, and the end from its first side towards described second internal electrode forms groove
The end of on second side of the described laminated body relative, exposing described second internal electrode with described first side, and on the other hand, separate from described second side end of first internal electrode, and the end from its first side towards described first internal electrode forms groove
In described groove, fill the Young's modulus insulator lower respectively than described piezoelectrics.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003202735A JP4771649B2 (en) | 2003-07-28 | 2003-07-28 | Manufacturing method of multilayer electronic component |
| JP202735/2003 | 2003-07-28 | ||
| JP426901/2003 | 2003-12-24 | ||
| JP010936/2004 | 2004-01-19 |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200810080741A Division CN100583480C (en) | 2003-07-28 | 2004-07-28 | Multi-layer piezoelectric component |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1830098A true CN1830098A (en) | 2006-09-06 |
| CN100448047C CN100448047C (en) | 2008-12-31 |
Family
ID=34262333
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200810080741A Active CN100583480C (en) | 2003-07-28 | 2004-07-28 | Multi-layer piezoelectric component |
| CNB2004800215169A Active CN100448047C (en) | 2003-07-28 | 2004-07-28 | Laminate type electronic component and production method therefor, laminate type piezoelectric element and jet device |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200810080741A Active CN100583480C (en) | 2003-07-28 | 2004-07-28 | Multi-layer piezoelectric component |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP4771649B2 (en) |
| CN (2) | CN100583480C (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101507007B (en) * | 2006-09-28 | 2010-11-17 | 京瓷株式会社 | Laminated piezoelectric element, injection apparatus and fuel injection system using the laminated piezoelectric element, and method for manufacturing laminated piezoelectric element |
| CN101558506B (en) * | 2006-12-15 | 2011-03-16 | 京瓷株式会社 | Laminated piezoelectric element, jetting device provided with the laminated piezoelectric element, and fuel jetting system |
| CN101785125B (en) * | 2007-09-27 | 2012-07-18 | 京瓷株式会社 | Multilayer piezoelectric element, injector equipped with the same and fuel injection system |
| US8421740B2 (en) | 2008-09-18 | 2013-04-16 | JVC Kenwood Corporation | Liquid crystal display device and image display method thereof |
| CN101978519B (en) * | 2008-01-23 | 2013-12-18 | 埃普科斯股份有限公司 | Piezoelectric multilayer component |
| CN101544114B (en) * | 2008-03-27 | 2014-07-16 | 精工爱普生株式会社 | Liquid ejecting head, liquid ejecting apparatus, and actuator |
| CN106653994A (en) * | 2017-01-23 | 2017-05-10 | 合肥工业大学 | Single-layer electrode type ionic polymer-metal composites (IMPC) structure and preparation method thereof |
| CN107728312A (en) * | 2017-10-24 | 2018-02-23 | 上海天马微电子有限公司 | A kind of spatial light modulator and display device |
| CN111344825A (en) * | 2017-11-15 | 2020-06-26 | 株式会社村田制作所 | Thin film capacitor |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5573261B2 (en) * | 2010-03-18 | 2014-08-20 | 株式会社村田製作所 | Multilayer ceramic capacitor, manufacturing method thereof and internal stress evaluation method |
| JP2011249659A (en) * | 2010-05-28 | 2011-12-08 | Kyocera Corp | Piezoelectric element, injector and fuel injection system comprising it |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2540939B2 (en) * | 1989-04-14 | 1996-10-09 | 富士電機株式会社 | Multilayer piezoelectric actuator element |
| JPH04299588A (en) * | 1991-03-28 | 1992-10-22 | Nec Corp | Electrostriction effect element |
| JPH05121791A (en) * | 1991-10-29 | 1993-05-18 | Nippondenso Co Ltd | Electrostrictive actuator |
| JP3397753B2 (en) * | 1999-09-30 | 2003-04-21 | ティーディーケイ株式会社 | Multilayer piezoelectric element and manufacturing method thereof |
| JP4802353B2 (en) * | 1999-12-08 | 2011-10-26 | Ｔｄｋ株式会社 | Multilayer piezoelectric ceramic electronic component and manufacturing method thereof |
| JP2001179972A (en) * | 1999-12-27 | 2001-07-03 | Nec Eng Ltd | Laminated piezoelectric element |
| JP2002289932A (en) * | 2001-03-22 | 2002-10-04 | Kyocera Corp | Laminated piezoelectric element, manufacturing method therefor, and jetting device |
| JP3852308B2 (en) * | 2001-07-09 | 2006-11-29 | 株式会社村田製作所 | Multilayer piezoelectric element, manufacturing method thereof, and piezoelectric actuator |
| JP3860746B2 (en) * | 2001-12-26 | 2006-12-20 | 京セラ株式会社 | Multilayer piezoelectric element and injection device |
-
2003
- 2003-07-28 JP JP2003202735A patent/JP4771649B2/en not_active Expired - Fee Related
-
2004
- 2004-07-28 CN CN200810080741A patent/CN100583480C/en active Active
- 2004-07-28 CN CNB2004800215169A patent/CN100448047C/en active Active
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101507007B (en) * | 2006-09-28 | 2010-11-17 | 京瓷株式会社 | Laminated piezoelectric element, injection apparatus and fuel injection system using the laminated piezoelectric element, and method for manufacturing laminated piezoelectric element |
| CN101558506B (en) * | 2006-12-15 | 2011-03-16 | 京瓷株式会社 | Laminated piezoelectric element, jetting device provided with the laminated piezoelectric element, and fuel jetting system |
| CN101785125B (en) * | 2007-09-27 | 2012-07-18 | 京瓷株式会社 | Multilayer piezoelectric element, injector equipped with the same and fuel injection system |
| CN101978519B (en) * | 2008-01-23 | 2013-12-18 | 埃普科斯股份有限公司 | Piezoelectric multilayer component |
| CN101544114B (en) * | 2008-03-27 | 2014-07-16 | 精工爱普生株式会社 | Liquid ejecting head, liquid ejecting apparatus, and actuator |
| US8421740B2 (en) | 2008-09-18 | 2013-04-16 | JVC Kenwood Corporation | Liquid crystal display device and image display method thereof |
| CN106653994A (en) * | 2017-01-23 | 2017-05-10 | 合肥工业大学 | Single-layer electrode type ionic polymer-metal composites (IMPC) structure and preparation method thereof |
| CN106653994B (en) * | 2017-01-23 | 2019-02-12 | 合肥工业大学 | A kind of single-layer electrodes type IPMC structure and its preparation process |
| CN107728312A (en) * | 2017-10-24 | 2018-02-23 | 上海天马微电子有限公司 | A kind of spatial light modulator and display device |
| US10466495B2 (en) | 2017-10-24 | 2019-11-05 | Shanghai Tianma Micro-electronics Co., Ltd. | Spatial light modulator and display device |
| CN111344825A (en) * | 2017-11-15 | 2020-06-26 | 株式会社村田制作所 | Thin film capacitor |
| CN111344825B (en) * | 2017-11-15 | 2022-01-25 | 株式会社村田制作所 | Thin film capacitor |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4771649B2 (en) | 2011-09-14 |
| JP2005050837A (en) | 2005-02-24 |
| CN100583480C (en) | 2010-01-20 |
| CN100448047C (en) | 2008-12-31 |
| CN101271957A (en) | 2008-09-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1961434A (en) | Multilayer piezoelectric element and method for manufacturing same | |
| US7902726B2 (en) | Multi-layer piezoelectric device | |
| CN1314058C (en) | Laminated ceramic electronic element and producing method thereof | |
| CN1474467A (en) | Method for producing laminated piezoelectric parts and laminated piezoelectric parts | |
| JP2004297041A (en) | Laminated piezoelectric element | |
| CN1202579C (en) | Piezoelectric transformer device | |
| CN1830098A (en) | Laminate type electronic component and production method therefor, laminate type piezoelectric element and jet device | |
| CN1856886A (en) | Multilayer piezoelectric device | |
| CN1188916C (en) | Multi-layer piezoelectric device and manufacture thereof | |
| CN1126661C (en) | Ink jet head, method of manufacturing ink jet head and ink jet recorder | |
| CN1701048A (en) | Piezoelectric porcelain composition, piezoelectric element, and method for production thereof | |
| JP4803956B2 (en) | Piezoelectric ceramics, laminated piezoelectric element using the same, and jetting apparatus | |
| CN1839487A (en) | Piezoelectric/electrostrictive device | |
| JP2010522973A (en) | LAMINATED PIEZOELECTRIC ELEMENT, INJECTION DEVICE USING THE SAME, AND METHOD FOR PRODUCING LAMINATED PIEZOELECTRIC ELEMENT | |
| CN1502469A (en) | Piezoelectric ceramics, actuator and makking method, printing head and ink-jet printer | |
| CN1871716A (en) | Multilayer piezoelectric element and jet device using same | |
| CN1560933A (en) | Electronic component | |
| CN1956234A (en) | Perovskite type oxide material, piezoelectric element using the same, liquid discharge head and liquid discharge apparatus, and manufacturing method | |
| CN1914136A (en) | Piezoelectric ceramic composition | |
| JP4889200B2 (en) | Multilayer piezoelectric element and injection device | |
| JP5328750B2 (en) | Multilayer piezoelectric element and jetting apparatus using the same | |
| CN1496833A (en) | Actuator and its manufacturing method and print head | |
| JP4986486B2 (en) | Multilayer piezoelectric element and jetting apparatus using the same | |
| JP4822664B2 (en) | Multilayer piezoelectric element, manufacturing method thereof, and injection apparatus | |
| CN101065854A (en) | Piezoelectric/electrostrictive 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 |