CN1564451A - Mini piezoelectric drive for MEMS - Google Patents
Mini piezoelectric drive for MEMS Download PDFInfo
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- CN1564451A CN1564451A CN 200410008677 CN200410008677A CN1564451A CN 1564451 A CN1564451 A CN 1564451A CN 200410008677 CN200410008677 CN 200410008677 CN 200410008677 A CN200410008677 A CN 200410008677A CN 1564451 A CN1564451 A CN 1564451A
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- multilayer film
- film composite
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- composite piezoelectric
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Abstract
Symmetrical parallel cascaded drives in suspension girder structure is formed relative to symmetry axis X though connection of tail trimmers on two ends or middle of suspension elastic beam. Middle parts of suspension girder on two sides of drive through connection of tail trimmer are connected to substrate so as to form fixed end. Number of parallel cascaded suspension girders can be equal or larger than 3. Composite piezoelectric unit in multilayer film in each suspension elastic beam is distributed symmetrical to Y-axis. Thus, piezoelectric drive having large vertical displacement is configured in multistage of going forward one by one. Features are large driving force, lowered driving voltage, and reduced length, as well as high reliability and simple technique.
Description
Technical field
The invention belongs to the microelectron-mechanical field, particularly can on microchip, realize a kind of miniature piezoelectric driver that is used for MEMS that big vertical displacement drives.
Background technology
Along with progress of science and technology, systems such as electronics, machinery develop towards miniaturization, microminiaturized direction, the high density of chip, multi-functional, the intelligent integrated important directions that becomes people's research.In recent ten years, based on large scale integrated circuit manufacturing technology and the exclusive special process of micromachining technology, realize the multi-functional integrated of MIniature machinery structure, miniature actuator, microelectronic component and circuit system, form so-called microelectromechanical systems (MicroElectroMachanical System, be called for short MEMS), or micro-system (Microsystem).The progress of this microsystems technology makes the ic manufacturing technology based on advanced person's semiconductor technology develop into manufacturing sophisticated electronic mechanical system on microchip, forms SOC (system on a chip) integrated (SOC).With microminiaturized, integrated, intelligent, information-based, advanced person is fabricated to the MEMS technology of characteristics from being designed into manufacturing, not only based on microelectric technique, and relate to many technology-oriented disciplines such as computer technology, the communication technology, microelectric technique, automatic control technology, Machine Design and manufacturing, can be described as the complex art of a multidisciplinary intersection.Based on complicated micro-system such as the microsensor of MEMS technology, miniature actuator, micro-optical systems, radio system, microbe chip, microfluidic device, stereo integrated circuit, the existing considerable industries such as industry, military affairs, biology, medical science that are applied to.
At present, physical principles such as static, electromagnetism, heat, piezoelectricity, marmem extensively are applied to MEMS actuator and driver.Advantages such as electrostatic and piezoelectric type microactrator has the precision height, do not generate heat, response speed is very fast.Through people's unremitting effort and broad research for many years, the static microactrator has become the vitals that MEMS drives, and simultaneously, the application of other little execution mechanism also obtains deep research.But, utilize existing little execution architecture of these principles generally to have big driver size, take more chip area, and the vertical drive displacement that realizes on substrate is limited, complex manufacturing technology, reliability are not high, and power consumption is big, and the life-span is short.In being subjected to the MEMS piezoelectric membrane type of drive of broad research, adopt cantilever beam structure mostly, because the elongation of piezoelectric membrane is limited, so the maximum deflection displacement on the cantilever beam structure is very limited, simultaneously, be driven structure and when realizing vertical displacement, also be accompanied by lateral shift and rotation.This feature limits the extensive use of Piezoelectric Driving mode in the MEMS field, the ripe MEMS commercialized device that causes present employing piezoelectric membrane to drive seldom occurs.This cantilever Drive Structure will realize big vertical displacement, require to increase the length of beam and increase driving voltage, so just one side has increased the cantilever beam static deflection amount that is caused by gravity, when causing not making alive, cantilever promptly has big yaw displacement, seriously limits its range of application.On the other hand, the straight cantilever beam Drive Structure of this length significantly reduces the mechanical vibration strength of driver, is easy to generate jitter phenomenon in the work, and very easily is hit and fractures.In addition, the straight cantilever Drive Structure of the list of this length has increased the inertia effects of cantilever itself, makes the operating frequency of driver very low, the application scenario that the many operating frequencies of incompatibility are higher.In addition, for obtaining big displacement, high driving voltage very easily causes piezoelectric membrane to puncture, and to the quality proposition higher requirement of piezoelectric membrane, increases the technology difficulty of piezoelectric membrane deposit.High driving voltage brings many additive effects to piezoelectric membrane simultaneously, and has increased the complexity of corresponding electronic circuit.At manufacture view, the long cantilever that easily shakes significantly increases the complexity of manufacturing, reduces the rate of finished products of micromachined.Long driver length also makes it be difficult to the application of adaptation in some micro structural components or device array.These have all seriously limited the application of cantilever beam piezoelectric actuator in microelectronic mechanical devices and system.
Summary of the invention
The purpose of this invention is to provide the miniature piezoelectric driver of a kind of MEMS of being used for, it is characterized in that: this MEMS miniature piezoelectric driver is to adopt the multistage mode of going forward one by one, and increases the Piezoelectric Driving displacement.At the two ends of suspension spring beam 1 or middlely connect through tail trimmer 3, become symmetry cascade suspension beam structure side by side with respect to the symmetry axis X-shaped, structure on two sides is identical, and the overarm middle part in driver two outsides connects the tail trimmer 4 formation stiff end that links to each other with substrate by substrate; In each overarm, be symmetry axis with the central vertical bisector Y of length direction, segmented deposition is pressed multilayer film composite piezoelectric unit 4 symmetrically, and every section multilayer film composite piezoelectric unit 2 forms the driver element that utilizes piezoelectric effect with following suspension spring beam 1; Multilayer film composite piezoelectric unit (2) on every suspension spring beam 1 is symmetrically distributed with symmetry axis Y, and the multilayer film composite piezoelectric unit 2 of each side can be 2,4,6 or 8, in whole Drive Structure, on the suspension spring beam 1 of symmetry axis X both sides, apply voltage with symmetric mode, in each side of symmetry axis X, each suspension spring beam 1 applies opposite polarity voltage with the upper and lower electrode of the multilayer film composite piezoelectric unit of the same side contiguous suspension spring beam 1 same position; Upper and lower electrode in the contiguous multilayer film composite piezoelectric of upper and lower electrode layer and its same side unit of each multilayer film composite piezoelectric unit of each side of symmetry axis Y applies opposite polarity voltage; Simultaneously, two the most contiguous upper and lower electrodes in multilayer film composite piezoelectric unit apply the voltage of identical polar in symmetry axis Y both sides.
Described multilayer film composite piezoelectric unit is on elastic film beam 1, resilient coating 5 is arranged from bottom to up, mutually unconnected mea layers 6 down, piezoelectric layer 7 and upper film electrode layer 8 complex superposition with multilayer film composite piezoelectric unit 2 of definite shape form, can also cover one deck insulating medium layer 9 at the upper electrode film laminar surface, top electrode lead-in wire 10, bottom electrode lead-in wire 11 are connected with upper film electrode layer 8, following mea layers 6 respectively.
The number of the overarm of described cascade arranged side by side can be for being equal to or greater than 3 integer.
Described piezoelectric layer 7 can be a kind of piezoelectric among PZT, PLZT, ZnO, AlN, the PVDF or is combined into the composite membrane of the piezoelectricity Seed Layer of multi-layer piezoelectric film or piezoelectric membrane and deposit in advance by more than one piezoelectric.
Described suspension spring beam 1 can be the compound tunic of one or more elastomeric materials in monocrystalline silicon, polysilicon, silicon dioxide, amorphous silicon, the silicon nitride.
Two the most contiguous multilayer film composite piezoelectric unit 2 of described symmetry axis (Y) both sides can couple together, and form a big multilayer film composite piezoelectric unit.
The invention has the beneficial effects as follows and adopt a kind of suspension Drive Structure of the multistage cascade of going forward one by one to realize big vertical displacement.Effectively shortened the length of driver, made it can save device area significantly in some applications; Reduced driving voltage; Improve the operating frequency of driver, had good device drive performance.Simultaneously, it is simple in structure, has very high device reliability, and technology is simple, and easily processing has higher fabrication yield, is fit to produce in batches.
Description of drawings:
Fig. 1 for the suspension spring beam and on multilayer film composite piezoelectric cell schematics.
Fig. 2 applies specific voltage rear drive beam distortion schematic diagram for the multilayer film composite piezoelectric unit on the suspension spring beam.
The activation configuration schematic diagram of Fig. 3 for constituting by four suspension flexible drive beams.
Fig. 4 is the drive operation principle schematic that four suspension flexible drive beams constitute.
The activation configuration schematic diagram of Fig. 5 for constituting by three suspension flexible drive beams.
Fig. 6 is seven or eight drive operation principle schematic that suspension flexible drive beam constitutes.
Fig. 7 is a multilayer film composite piezoelectric cellular construction schematic diagram.
Embodiment
The invention provides the miniature piezoelectric driver of a kind of MEMS of being used for.On this MEMS miniature piezoelectric driver, adopt the multistage mode of going forward one by one, increase the Piezoelectric Driving displacement.At the two ends of suspension spring beam 1 or middlely connect through tail trimmer 3, become symmetry cascade suspension beam structure side by side with respect to the symmetry axis X-shaped, the number of the overarm of cascade can be for being equal to or greater than 3 integer side by side.Symmetry axis X structure on two sides is identical, and the overarm middle part in driver two outsides links to each other with substrate by substrate connection tail trimmer 4 and forms stiff end; In each overarm, be symmetry axis with the central vertical bisector Y of length direction, segmented deposition is pressed multilayer film composite piezoelectric unit 2 symmetrically, and every section multilayer film composite piezoelectric unit 2 forms the driver element that utilizes piezoelectric effect with following suspension spring beam 1; Multilayer film composite piezoelectric unit 2 on every suspension spring beam 1 is symmetrically distributed with symmetry axis Y, and the multilayer film composite piezoelectric unit 2 of each side can be 2,4,6 or 8, in whole Drive Structure, on the suspension spring beam 1 of symmetry axis X both sides, apply voltage with symmetric mode, in each side of symmetry axis X, each suspension spring beam 1 applies opposite polarity voltage with the upper and lower electrode of the multilayer film composite piezoelectric unit of the same side contiguous suspension spring beam 1 same position; Upper and lower electrode in the contiguous multilayer film composite piezoelectric of upper and lower electrode layer and its same side unit of each multilayer film composite piezoelectric unit of each side of symmetry axis Y applies opposite polarity voltage; Simultaneously, two the most contiguous upper and lower electrodes in multilayer film composite piezoelectric unit apply the voltage (as shown in Figure 1 and Figure 2) of identical polar in symmetry axis Y both sides.
Above-mentioned piezoelectric layer 7 can be a kind of piezoelectric among PZT, PLZT, ZnO, AlN, the PVDF or is combined into the composite membrane of the piezoelectricity Seed Layer of multi-layer piezoelectric film or piezoelectric membrane and deposit in advance by more than one piezoelectric.
Above-mentioned suspension spring beam 1 can be the compound tunic of one or more elastomeric materials in monocrystalline silicon, polysilicon, silicon dioxide, amorphous silicon, the silicon nitride.
Two the most contiguous multilayer film composite piezoelectric unit 2 of described symmetry axis Y both sides can couple together, and form a big multilayer film composite piezoelectric unit (as Fig. 3, shown in Figure 5).
Figure 7 shows that multilayer film composite piezoelectric unit is on elastic film beam 1, resilient coating 5 is arranged from bottom to up, mutually unconnected mea layers 6 down, piezoelectric layer 7 and upper film electrode layer 8 complex superposition with multilayer film composite piezoelectric unit 2 of definite shape form, can also cover one deck insulating medium layer 9 at the upper electrode film laminar surface, top electrode lead-in wire 10, bottom electrode lead-in wire 11 are connected with upper film electrode layer 8, following mea layers 6 respectively.Form a kind of multistage cascaded symmetric type of drive of going forward one by one.
For the situation that an elasticity overarm is only arranged, as shown in Figure 1.The elasticity overarm is gone up and is formed four piezoceramic multilayer film unit A, B, C, D.Wherein, A, B and C, D are with respect to central symmetry axis Y symmetry.If apply identical voltage between the upper/lower electrode of piezoceramic multilayer film unit A, C, and it is identical to apply size between B, D upper/lower electrode, the polarity opposite voltage.Then whole overarm can produce bending as shown in Figure 2.
If elasticity overarm unit shown in Figure 1 is connected to form four beam cascade drivers shown in Figure 3 through short beam, then whole driver is with respect to symmetry axis X symmetry.Driver links to each other with substrate by short beam 4.Because of driver with respect to the X-axis symmetry, so if the corresponding upper and lower electrode of piezoceramic multilayer film applies the voltage and the load of symmetry in the overarm of X-axis both sides, then the malformation and the displacement of symmetry axis (X) both sides are identical.
From structure shown in Figure 3, the structure of X-axis upside, if apply identical voltage between piezoceramic multilayer film unit 1A, 1C, 2B, the upper and lower electrode of 2D, and it is identical to apply size between 1B, 1D, the upper and lower electrode of 2A, 2C, the polarity opposite voltage.Then whole suspension structure may produce bending as shown in Figure 4, (end view).At this moment 3 of the short beams on the X-axis produce the maximum perpendicular displacement, and the direction of displacement is different and different with the polarity of voltage that each piezoceramic multilayer film unit applied.
Form driver by single overarm shown in Figure 1, versions such as three beams, four beams, five beams, six beams, seven beams, eight beams can be arranged according to its number difference, they all are the big vertical displacements of effect generation of going forward one by one by different number overarms.
For three beams (as shown in Figure 5), four beam drivers (as shown in Figure 3), when the malformation (end view) as shown in Figure 4 that applies after requiring voltage.
For seven beams, eight beam drivers, when the malformation (end view) as shown in Figure 6 that applies after requiring voltage.
Above-mentioned two kinds of situations all are in X-axis and Y-axis joint place maximum displacement to take place.
For five beams, six beam drivers, when apply require voltage after maximum displacement occur in the middle of the two ends of long overarm.
The miniature piezoelectric driver of realizing this patent has the kinds of processes method.Only set forth wherein a kind of method below: at first use the twin polishing silicon substrate, deposit silicon nitride after the two-sided thermal oxidation, back side photolithographic structures window, etch away silicon nitride, float the thermal oxide layer that exposes, utilize anisotropic etchants such as KOH or TMAH to carry out bulk silicon etching, form silicon thin film, remove the silicon nitride and the thermal oxide layer on two sides then, the thermal oxide film of the suitable thickness that regrows carries out the manufacture craft of PZT (lead zirconate titanate) composite multi-layer film as resilient coating in the front, the deposit lower electrode layer successively in the front, piezoelectric membrane, upper electrode layer, and adopt physics or chemical etching technology, etch top electrode successively, piezoelectric layer, the bottom electrode figure, last deposit dielectric insulating film adopts physics or chemical etching technology etching upper/lower electrode fairlead, depositing metal and etching line again.Photoetching is subsequently also adopted anisotropic etch process etching silicon fiml, discharges suspension structure, forms Drive Structure.In this method example, bottom electrode can be made of titanium/platinum composite bed or platinum, and piezoelectric membrane is by piezoelectricity Seed Layer PbTiO
3Constitute with the PZT composite bed, top electrode is made of titanium/platinum composite bed or platinum.
Claims (4)
1. miniature piezoelectric driver that is used for MEMS is characterized in that: at the two ends of suspension spring beam (1) or middlely connect through tail trimmer (3), become the symmetry driver of cascade suspension beam structure side by side with respect to the symmetry axis X-shaped; Structure on two sides is identical, and the overarm middle part in driver two outsides links to each other with substrate by substrate connection tail trimmer (4) and forms stiff end; In each overarm, central vertical bisector Y with length direction is a symmetry axis, segmented deposition is pressed multilayer film composite piezoelectric unit (2) symmetrically, and every section multilayer film composite piezoelectric unit (2) forms the driver element that utilizes piezoelectric effect with following suspension spring beam (1); Multilayer film composite piezoelectric unit (2) on every suspension spring beam (1) is symmetrically distributed with symmetry axis Y, and the multilayer film composite piezoelectric unit (2) of each side can be 2,4,6 or 8, in whole Drive Structure, suspension spring beam (1) in symmetry axis X both sides upward applies voltage with symmetric mode, in each side of symmetry axis X, each suspension spring beam (1) applies opposite polarity voltage with the upper and lower electrode of the multilayer film composite piezoelectric unit (2) of contiguous suspension spring beam (1) same position in the same side; Upper and lower electrode in the contiguous multilayer film composite piezoelectric of upper and lower electrode layer and its same side unit of each multilayer film composite piezoelectric unit of each side of symmetry axis Y applies opposite polarity voltage; Simultaneously, two the most contiguous upper and lower electrodes in multilayer film composite piezoelectric unit apply the voltage of identical polar in symmetry axis Y both sides.
2. according to the described miniature piezoelectric driver that is used for MEMS of claim 1, it is characterized in that: described piezoceramic multilayer film, every section piezoelectricity composite multi-layer film unit is on the elastic film beam, resilient coating (5) is arranged from bottom to up, unconnected mutually mea layers (6) down, piezoelectric layer (7) and upper film electrode layer (8) complex superposition with multilayer film composite piezoelectric unit (2) of definite shape form, can also cover one deck insulating medium layer (9) at the upper electrode film laminar surface, top electrode lead-in wire (10), bottom electrode lead-in wire (11) respectively with upper film electrode layer (8), following mea layers (6) connects.
3. according to the described miniature piezoelectric driver that is used for MEMS of claim 1, it is characterized in that: the number of the overarm of described cascade arranged side by side can be for being equal to or greater than 3 integer.
4. MEMS miniature piezoelectric driver according to claim 1 is characterized in that: the most contiguous two multilayer film composite piezoelectric unit (2), described symmetry axis Y both sides can couple together, and form a big multilayer film composite piezoelectric unit.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100086776A CN1317815C (en) | 2004-03-18 | 2004-03-18 | Mini piezoelectric drive for MEMS |
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| Application Number | Priority Date | Filing Date | Title |
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| CNB2004100086776A CN1317815C (en) | 2004-03-18 | 2004-03-18 | Mini piezoelectric drive for MEMS |
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| Publication Number | Publication Date |
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| CN1564451A true CN1564451A (en) | 2005-01-12 |
| CN1317815C CN1317815C (en) | 2007-05-23 |
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| CNB2004100086776A Expired - Fee Related CN1317815C (en) | 2004-03-18 | 2004-03-18 | Mini piezoelectric drive for MEMS |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101093966B (en) * | 2006-06-23 | 2010-12-22 | 株式会社东芝 | Piezoelectric driven mems device |
| CN103199733A (en) * | 2013-03-22 | 2013-07-10 | 北京大学 | Piezoelectric actuator and manufacturing method thereof |
| US8776514B2 (en) | 2007-12-14 | 2014-07-15 | Lei Wu | Electrothermal microactuator for large vertical displacement without tilt or lateral shift |
| CN105071690A (en) * | 2015-07-20 | 2015-11-18 | 南京航空航天大学 | Novel piezoelectric linear actuation two-dimensional image-stabilizing platform |
| CN107102174A (en) * | 2017-05-16 | 2017-08-29 | 中国计量科学研究院 | A kind of preparation method for the extraordinary probe that micro-measurement apparatus is scanned for needlepoint type |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6229640B1 (en) * | 1999-08-11 | 2001-05-08 | Adc Telecommunications, Inc. | Microelectromechanical optical switch and method of manufacture thereof |
| US6360036B1 (en) * | 2000-01-14 | 2002-03-19 | Corning Incorporated | MEMS optical switch and method of manufacture |
| CN1359733A (en) * | 2002-01-29 | 2002-07-24 | 清华大学 | Piezoelectrically driven microspray method and apparatus for atomizing administration |
| CN2689586Y (en) * | 2004-03-18 | 2005-03-30 | 清华大学 | MEMS miniature piezoelectric drivers |
-
2004
- 2004-03-18 CN CNB2004100086776A patent/CN1317815C/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101093966B (en) * | 2006-06-23 | 2010-12-22 | 株式会社东芝 | Piezoelectric driven mems device |
| US8776514B2 (en) | 2007-12-14 | 2014-07-15 | Lei Wu | Electrothermal microactuator for large vertical displacement without tilt or lateral shift |
| CN103199733A (en) * | 2013-03-22 | 2013-07-10 | 北京大学 | Piezoelectric actuator and manufacturing method thereof |
| CN103199733B (en) * | 2013-03-22 | 2015-06-10 | 北京大学 | Piezoelectric actuator and manufacturing method thereof |
| CN105071690A (en) * | 2015-07-20 | 2015-11-18 | 南京航空航天大学 | Novel piezoelectric linear actuation two-dimensional image-stabilizing platform |
| CN107102174A (en) * | 2017-05-16 | 2017-08-29 | 中国计量科学研究院 | A kind of preparation method for the extraordinary probe that micro-measurement apparatus is scanned for needlepoint type |
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| CN1317815C (en) | 2007-05-23 |
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Granted publication date: 20070523 Termination date: 20100318 |