DE102011120595A1 - Piezo element has contact electrodes that are extended transversely through piezoelectric layers and electrode layers - Google Patents

Piezo element has contact electrodes that are extended transversely through piezoelectric layers and electrode layers

Info

Publication number
DE102011120595A1
DE102011120595A1 DE201110120595 DE102011120595A DE102011120595A1 DE 102011120595 A1 DE102011120595 A1 DE 102011120595A1 DE 201110120595 DE201110120595 DE 201110120595 DE 102011120595 A DE102011120595 A DE 102011120595A DE 102011120595 A1 DE102011120595 A1 DE 102011120595A1
Authority
DE
Germany
Prior art keywords
piezo element
layers
characterized
contacting electrodes
according
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.)
Withdrawn
Application number
DE201110120595
Other languages
German (de)
Inventor
Peter Hess
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Buerkert Werke GmbH
Original Assignee
Buerkert Werke GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Buerkert Werke GmbH filed Critical Buerkert Werke GmbH
Priority to DE201110120595 priority Critical patent/DE102011120595A1/en
Publication of DE102011120595A1 publication Critical patent/DE102011120595A1/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L41/00Piezo-electric devices in general; Electrostrictive devices in general; Magnetostrictive devices in general; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L41/02Details
    • H01L41/04Details of piezo-electric or electrostrictive devices
    • H01L41/047Electrodes or electrical connection arrangements
    • H01L41/0472Connection electrodes of multilayer piezo-electric or electrostrictive devices, e.g. external electrodes
    • H01L41/0474Connection electrodes of multilayer piezo-electric or electrostrictive devices, e.g. external electrodes embedded within piezo-electric or electrostrictive material, e.g. via connections
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L41/00Piezo-electric devices in general; Electrostrictive devices in general; Magnetostrictive devices in general; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L41/08Piezo-electric or electrostrictive devices
    • H01L41/083Piezo-electric or electrostrictive devices having a stacked or multilayer structure

Abstract

The piezo element (10) has stacked piezoelectric layers (12), between which electrode layers (14) are arranged, and two contacting electrodes (16,18). The contact electrodes are extended transversely through the piezoelectric layers and electrode layers. The openings are formed in the electrode layer.

Description

  • The invention relates to a piezoelectric element having a plurality of stacked piezoelectric layers, between which electrode layers are arranged.
  • Such piezo elements are for example from the DE 10 2007 058 874 A1 and the WO 2011/044882 One difficulty is the electrical contacting of the electrode layers in the piezoelectric element. Contacting electrodes, also referred to as collecting electrodes, which are arranged on outer surfaces of the piezoelectric element are frequently used for this purpose. The collecting electrodes must be flexible so that they can withstand mechanical stresses that occur during expansion or contraction of the piezoelectric element in an electric field as a function of an electrical drive potential. The disadvantage here is that the collecting electrodes can easily break, whereby then the piezoelectric element is dysfunctional.
  • A further difficulty arises from the fact that the electrode layers are to be contacted alternately by the collecting electrodes, which is achieved, for example, by the fact that the electrode layers do not delimit the piezoelectric layers arranged therebetween over the entire surface, but edge regions are recessed. This has the disadvantage that form inactive areas in the piezoelectric layer, which can lead to cracking of the layers as a result.
  • It is therefore an object of the invention to provide a piezoelectric element which has a high mechanical stability.
  • The object is achieved with a piezoelectric element according to claim 1.
  • A piezoelectric element according to the invention has a plurality of stacked piezoelectric layers, between which electrode layers are arranged, and at least two contacting electrodes, which project through the piezoelement internally transversely to the piezoelectric layers and electrode layers. Since the contacting electrodes are arranged on the inside of the piezoelement and not on one or more outer surfaces as known, the contacting electrodes are protected and their stability is increased. The piezoelectric element itself shields the contacting electrodes from outside influences, so to speak. In addition, recesses in edge regions of the electrode layers can be dispensed with in the piezoelectric element according to the invention. The piezo layers can be completely covered by electrode layers.
  • The piezoelectric layers consist for example of a lead-zirconate-titanate compound. However, it is also possible to use other materials which have piezoelectric properties.
  • Suitable electrode layers are electrically conductive materials, such as metals or metal alloys. Here, for example, platinum or copper have proved favorable.
  • In one embodiment, in the piezoelectric layers and the electrode layers aligned, preferably cylindrical feedthroughs are arranged for the contacting electrodes. This has the advantage that no connection or fastening means are required, as is the case in the prior art, where the contacting electrodes are arranged on outer surfaces of the piezoelectric element.
  • The geometry of the bushings is favorably matched to the geometry of the contacting electrodes. This means that, for example, in the selection of cylindrical wire as a contacting electrode, the bushings are also formed correspondingly cylindrical. Of course, other geometries are conceivable. Especially when electrodes are produced by vapor deposition or sputtering, their geometry, defined by masks used there, quasi arbitrary selectable.
  • In a further embodiment, at least a first and a second passage are arranged in each electrode layer. Thus, in a simple manner for forming an electric field, a positive and a negative contacting electrode can be introduced into the piezoelectric element.
  • Advantageously, the bushings differ in terms of their diameter. In one embodiment of the piezoelectric element, first passages have a larger diameter than the second.
  • It can thereby be achieved that the contacting electrodes are in electrical contact with the second feedthroughs, the diameters of which approximately correspond to the electrode diameter, while the contacting electrodes are passed through first passages with a larger diameter, without electrical contact being produced.
  • This means that the first lead-throughs for contacting electrodes are made possible without establishing an electrical contact through regions that are electrically conductive, such as the electrode layers, without these first Feedthroughs would have to be isolated by a special insulation material.
  • Alternatively, the first feedthroughs can be made with a diameter that is only slightly larger than the diameter of the contacting electrodes, but also additionally insulated with a non-conductive material such as plastic or silicon oxide, in particular with silicon dioxide. As a result, in addition, the cavities formed by the bushings in the piezoelectric element are filled, which in turn has a positive effect on the mechanical stability of the contacting electrodes and ensures that, despite the only slightly larger diameter of the first bushings, no unintentional contacting takes place. In addition, the insulation prevents any sparking at the electrode edges. Finally, in the process of insulating simultaneously occurring any unevenness can be compensated.
  • In a further embodiment, the electrode layers in the piezoelectric element in the stacking direction alternately have first and second feedthroughs. This has the advantage that a contacting electrode is not in electrical contact with each electrode layer but, as required for the piezo element, only with every second one.
  • A further advantage is that all electrode layers in the piezoelectric element have an identical geometry with a first and a second feedthrough and two adjacent electrode layers differ only in that they are arranged rotated in an extension plane perpendicular to the stacking direction by 180 ° to each other.
  • The feedthroughs may be introduced into the piezoelectric layers and the electrode layers by known methods such as ultrasonic drilling, etching or laser technology.
  • In a further preferred embodiment, the contacting electrodes are formed as ductile metallic wires. The wires are made by weaving technique through the feedthroughs in the piezoelectric and electrode layers. In this case, an electrical contact between the wires and the electrode layers on the second bushings must be ensured. This can be achieved, for example, by carrying out a wire at a lower temperature than the desired subsequent operating temperature of the piezoelectric element with a certain amount of clearance through the layers, which expands somewhat when it is heated to the operating temperature, so that reliable contacting is obtained.
  • Alternatively, the contacting electrodes are made by metal depositing a metal having ductile properties. Ductile materials are characterized by the fact that they are plastically deformable and mechanical loads can be intercepted to a certain extent, without causing a material breakage.
  • Particularly advantageously, the piezoelectric element is biased by the contacting electrodes, without additional biasing elements are required. Piezo elements must be biased when exposed to tensile loads. The bias can be done for example by a production-related shrinkage. But it can also be used separate biasing elements.
  • In a further embodiment, the piezoelectric element has two non-conductive cover layers. The cover layers close off the stacked layers of piezoelectric layers and electrode layers to the outside. They can be formed, for example, of silicon dioxide.
  • In a cover layer which terminates the piezoelectric element, an electronic control unit, in particular designed as an FPGA, is advantageously arranged. As a result, the piezo element is particularly compact. Of course, the control electronics can also be accommodated in a separate component, Further advantages and embodiments of the invention will be described with reference to the accompanying figures. Hereby show:
  • 1 a perspective top view of a piezoelectric element according to the invention;
  • 2 a side view of the piezoelectric element according to 1 ;
  • 3 a plan view of the piezo element according to 1 ; and
  • 4 a sectional view of the piezoelectric element of 3 ,
  • In 1 is a perspective top view of a piezoelectric element according to the invention 10 shown. The piezo element 10 comprises several layers stacked alternately: piezoelectric layers 12 and electrode layers 14 , Every piezoelectric layer 12 has two openings 21 on, and each electrode layer 14 has two bushings 20 . 22 on. Two contacting electrodes 16 . 18 protrude through the piezoelectric element 10 inboard across the layers so that they pass through the bushings 20 . 22 and the openings 21 extend. "Interior" means that the contacting electrodes 16 . 18 within of the body, which is formed by the piezoelectric layers and the electrode layers, and not on outer surfaces of the piezoelectric element 10 are arranged and exposed. "Transverse" means oblique or perpendicular to the planes defined by the piezoelectric layers.
  • The piezo element 10 , as in 1 shown, has a square footprint passing through the piezoelectric layers 12 and the electrode layers 14 continues in the stacking direction, so that the piezoelectric element 10 has a substantially cuboid geometry. In the 1 illustrated embodiment of the piezoelectric element according to the invention is, as regards its geometry, of course only by way of example. The piezoelectric element can likewise have a circular, hexagonal or differently configured base surface. It is essential to the invention that the contacting electrodes are arranged in the interior of the piezoelectric element and project through this transversely to the layers.
  • The piezoelectric layers 12 are made of material with piezoelectric properties such as lead zirconate titanate.
  • The electrode layers 14 are made of electrically conductive material, such as metals or alloys. Preferably, copper is used. But there are other materials possible. The electrode layers 14 are made thinner than the piezoelectric layers 12 ,
  • The piezo element 10 is preferably made by thin-film technology, wherein the individual layers are sequentially deposited. However, other manufacturing processes such as sol / gel processes can also be used.
  • The contacting electrodes 16 . 18 can also be made in layered construction, or they are made as a wire through the feedthroughs.
  • 2 shows a side view of the piezoelectric element 10 from 1 with the alternating piezoelectric layers 12 and the electrode layers 14 ,
  • The layers 12 . 14 are stacked substantially parallel to each other over the entire area.
  • In 3 is a plan view of the piezoelectric element 10 with the internal contacting electrodes 16 . 18 shown.
  • 4 shows a sectional view of the piezoelectric element 10 from 3 along the section line AA with the piezoelectric layers 12 , the electrode layers 14 and the internal contacting electrodes 16 . 18 that extend across the layers.
  • The electrode layers and the piezoelectric layers are gespapelt that the feedthroughs 20 . 22 and the openings 21 aligned with each other. Overall, two channels are formed in this way, which extend here perpendicular to the individual layers through the piezoelectric element.
  • The two openings 21 in each piezoelectric layer 12 each have the same diameter, about the diameter of the contacting electrodes 16 . 18 equivalent. To carry out the contacting electrodes 16 . 18 through the piezoelectric layers 12 To simplify, the diameter of the openings 21 but also be slightly larger than the diameter of the contacting electrodes 16 . 18 because the contacting electrodes 16 . 18 with the piezoelectric layers 12 do not have to be electrically connected.
  • The two bushings 20 . 22 in the electrode layers 14 are designed so that the diameter of the first implementation 20 is greater than the diameter of the second implementation 22 , The diameter corresponds to the second implementation 22 the diameter of the contacting electrodes 16 . 18 so that this with the electrode layers 14 to be in electrical contact. In the piezoelectric element, the electrode layers are alternately aligned so that a first feedthrough is located above a second feedthrough, etc. In other words, the electrode layers have 14 in the stacking direction one above the other alternately first and second passages 20 . 22 on, so that the contacting electrodes 16 . 18 with every second electrode layer 14 in electrical contact and each electrode layer 14 only from one of the two contacting electrodes 14 . 16 will be contacted.
  • The diameter of the first bushings 20 is compared to the diameter of the contacting electrodes 16 . 18 so large that between the contacting electrodes 16 . 18 and the electrode layers 14 at the first passages 20 there is no electrical connection. It is advantageous no additional insulation of the bushings 20 necessary. There along the of the bushings 20 22 and openings 21 formed channel alternate first and second feedthroughs, each electrode layer of only one of the two contacting electrodes 16 . 18 contacted. When viewed in the stacking direction, therefore, electrode layers alternate with the contacting electrode 16 in contact with electrode layers, the with the contacting electrode 18 keep in touch.
  • By means of a positive and a negative contacting electrode 16 . 18 , two adjacent electrode layers can 14 be contacted so that on the intermediate piezoelectric layer 12 an electric field works.
  • On the other hand, if there is an insulating layer between the first feedthroughs 20 and the contacting electrodes 16 . 18 can be used, the first executions 20 be made with a smaller diameter, without the risk of unwanted electrical contact exists.
  • The bushings 20 . 22 are made by known methods such as ultrasonic drilling or laser or etching technology.
  • The piezo element 10 is outwardly from each of a piezoelectric layer 12 limited.
  • In addition, cover layers can be provided which are not electrically conductive.
  • In a cover layer, a control electronics can be integrated, with the piezoelectric element 10 is controlled. This is also an FPGA suitable.
  • The contacting electrodes 16 . 18 may be formed as ductile wires and in the bushings 20 . 22 and openings 21 are used, or they are produced layer by layer by means of metal deposition by vapor deposition or sputtering. It is particularly advantageous that by process-induced shrinkage the contacting electrodes 16 . 18 the piezo element 10 preload without the need for additional biasing elements.
  • Alternatively, biasing elements in the piezoelectric element can 10 be used.
  • QUOTES INCLUDE IN THE DESCRIPTION
  • This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.
  • Cited patent literature
    • DE 102007058874 A1 [0002]
    • WO 2011/044882 [0002]

Claims (11)

  1. Piezo element ( 10 ) having a plurality of stacked piezoelectric layers ( 12 ) between which electrode layers ( 14 ), as well as at least two contacting electrodes ( 16 . 18 ), characterized in that the contacting electrodes ( 16 . 18 ) the piezo element ( 10 ) projecting inwardly transversely to the piezoelectric layers and electrode layers.
  2. Piezo element ( 10 ) according to claim 1, characterized in that in the piezoelectric layers ( 12 ) and the electrode layers ( 14 ) aligned, preferably cylindrical passages ( 20 . 22 ) and openings ( 21 ) are arranged for the contacting electrodes.
  3. Piezo element ( 10 ) according to claim 2, characterized in that in each electrode layer ( 14 ) at least one first ( 20 ) and a second ( 22 ) Implementation are arranged.
  4. Piezo element ( 10 ) according to claim 3, characterized in that the first implementation ( 20 ) has a larger diameter than the second ( 22 ).
  5. Piezo element ( 10 ) according to claim 3 or 4, characterized in that the electrode layers ( 14 ) in the stacking direction alternately first and second feedthroughs ( 20 . 22 ) exhibit.
  6. Piezo element ( 10 ) according to claim 3, 4 or 5, characterized in that the diameter of the contacting electrodes ( 16 . 18 ) is substantially the same size as the diameter of the second passage ( 22 ), so that the contacting electrodes ( 16 . 18 ) with every second electrode layer ( 14 ) on the second passages ( 22 ) are electrically connected together.
  7. Piezo element ( 10 ) according to one of the preceding claims, characterized in that the contacting electrodes ( 16 . 18 ) are formed as ductile metallic wires.
  8. Piezo element ( 10 ) according to one of the preceding claims, characterized in that the contacting electrodes ( 16 . 18 ) are produced by metal deposition.
  9. Piezo element ( 10 ) according to one of the preceding claims, characterized in that the piezo element ( 10 ) through the contacting electrodes ( 16 . 18 ) is biased.
  10. Piezo element ( 10 ) according to one of the preceding claims, characterized in that the piezo element ( 10 ) has two non-conductive cover layers.
  11. Piezo element ( 10 ) according to claim 10, characterized in that in a cover layer, a control electronics, in particular designed as FPGA, is arranged.
DE201110120595 2011-12-08 2011-12-08 Piezo element has contact electrodes that are extended transversely through piezoelectric layers and electrode layers Withdrawn DE102011120595A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE201110120595 DE102011120595A1 (en) 2011-12-08 2011-12-08 Piezo element has contact electrodes that are extended transversely through piezoelectric layers and electrode layers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE201110120595 DE102011120595A1 (en) 2011-12-08 2011-12-08 Piezo element has contact electrodes that are extended transversely through piezoelectric layers and electrode layers

Publications (1)

Publication Number Publication Date
DE102011120595A1 true DE102011120595A1 (en) 2013-06-13

Family

ID=48464536

Family Applications (1)

Application Number Title Priority Date Filing Date
DE201110120595 Withdrawn DE102011120595A1 (en) 2011-12-08 2011-12-08 Piezo element has contact electrodes that are extended transversely through piezoelectric layers and electrode layers

Country Status (1)

Country Link
DE (1) DE102011120595A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT519429A1 (en) * 2016-12-13 2018-06-15 Piezocryst Advanced Sensorics Measurement tables for measuring power or pushing and method for manufacturing such a measurement item tapel
AT519442A1 (en) * 2016-12-13 2018-06-15 Piezocryst Advanced Sensorics Measurement tables for measuring power or pushing and method for manufacturing such a measurement item tapel

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030117041A1 (en) * 2000-03-30 2003-06-26 Kazuaki Kurihara Piezoelectric actuator, method of manufacturing the same, ink-jet head using the same, and ink-jet printer
DE10320161A1 (en) * 2002-05-06 2004-03-18 Epcos Ag Piezoactuator has base body with piezoelectric layer stack and intermediate electrode layers; pre-formed contact element for contacting electrode layers is inserted into piezoactuator
DE10343997A1 (en) * 2003-09-23 2005-04-14 Robert Bosch Gmbh Piezoelectric element
JP2005175018A (en) * 2003-12-08 2005-06-30 Hokuriku Electric Ind Co Ltd Multilayer piezoelectric body and piezoelectric oscillating element
US20070278908A1 (en) * 2006-06-03 2007-12-06 Brother Kogyo Kabushiki Kaisha Piezoelectric actuator and liquid-droplet jetting head
DE102007058874A1 (en) 2007-12-06 2010-05-20 Siemens Ag Piezoelectric component for use in vehicles for controlling fuel injection valve, comprises stacked piezoelement, which comprises electrode layer made of electrode material
WO2011044882A2 (en) 2009-10-17 2011-04-21 Pi Ceramic Gmbh Keramische Technologien Und Bauelemente Multilayer piezoelectric actuator

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030117041A1 (en) * 2000-03-30 2003-06-26 Kazuaki Kurihara Piezoelectric actuator, method of manufacturing the same, ink-jet head using the same, and ink-jet printer
DE10320161A1 (en) * 2002-05-06 2004-03-18 Epcos Ag Piezoactuator has base body with piezoelectric layer stack and intermediate electrode layers; pre-formed contact element for contacting electrode layers is inserted into piezoactuator
DE10343997A1 (en) * 2003-09-23 2005-04-14 Robert Bosch Gmbh Piezoelectric element
JP2005175018A (en) * 2003-12-08 2005-06-30 Hokuriku Electric Ind Co Ltd Multilayer piezoelectric body and piezoelectric oscillating element
US20070278908A1 (en) * 2006-06-03 2007-12-06 Brother Kogyo Kabushiki Kaisha Piezoelectric actuator and liquid-droplet jetting head
DE102007058874A1 (en) 2007-12-06 2010-05-20 Siemens Ag Piezoelectric component for use in vehicles for controlling fuel injection valve, comprises stacked piezoelement, which comprises electrode layer made of electrode material
WO2011044882A2 (en) 2009-10-17 2011-04-21 Pi Ceramic Gmbh Keramische Technologien Und Bauelemente Multilayer piezoelectric actuator

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT519429A1 (en) * 2016-12-13 2018-06-15 Piezocryst Advanced Sensorics Measurement tables for measuring power or pushing and method for manufacturing such a measurement item tapel
AT519442A1 (en) * 2016-12-13 2018-06-15 Piezocryst Advanced Sensorics Measurement tables for measuring power or pushing and method for manufacturing such a measurement item tapel
AT519442B1 (en) * 2016-12-13 2018-09-15 Piezocryst Advanced Sensorics Measurement tables for measuring power or pushing and method for manufacturing such a measurement item tapel
AT519429B1 (en) * 2016-12-13 2018-09-15 Piezocryst Advanced Sensorics Measurement tables for measuring power or pushing and method for manufacturing such a measurement item tapel

Similar Documents

Publication Publication Date Title
EP2953431B1 (en) Plasma generator
CN101399116B (en) Capacitor and method of manufacturing the same
EP1636859B1 (en) Piezoelectric component with a predetermined breaking point, method for producing the component and use of the component
TW522053B (en) Piezo-bent-converter
DE19646676C1 (en) Piezo actuator with a new type of contact and manufacturing process
EP1984957B1 (en) Piezoceramic multilayer actuator, method for producing a piezoceramic multilayer actuator, and injection system
US7358655B2 (en) Electrical multilayered component and layer stack
DE10026005B4 (en) piezo actuator
US3390287A (en) Piezo-electric building units
EP1530805B1 (en) Piezoelectric actuator
US6930435B2 (en) Piezoelectric element
JP5069233B2 (en) Monolithic piezo actuator with rotating polarization direction in the transition region
EP3237881B1 (en) Sensor for detecting soot particles in an exhaust gas stream of a combustion engine, sensor system, method for operating a sensor, method for producing a sensor of this type and use of a sensor of this type
JP2007294904A (en) Piezoelectric actuator
US7999446B1 (en) Piezoelectronic device and method of fabricating the same
WO2006103154A1 (en) Monolithic piezoelectric component comprising a mechanical uncoupling, method for producing same and use thereof
US7271526B2 (en) Piezoelectric actuator
WO2009057699A1 (en) Elastic wave device
WO2006042791A1 (en) Piezoelectric actuator
KR100655094B1 (en) Method for the production of piezoelectric actuators and a piezoelectric actuator
JP5050164B2 (en) Piezoelectric actuator unit and manufacturing method thereof
JPH10229227A (en) Monolithic laminated actuator
AT503816A4 (en) Piezoelectric sensor
JP2010515249A (en) Piezoceramic multilayer actuator and manufacturing method thereof
US6232701B1 (en) Piezoelectric component and method for the manufacture thereof

Legal Events

Date Code Title Description
R163 Identified publications notified
R005 Application deemed withdrawn due to failure to request examination