CN209542648U

CN209542648U - A kind of piezoelectric transducer

Info

Publication number: CN209542648U
Application number: CN201920275143.1U
Authority: CN
Inventors: 陈显锋
Original assignee: Foshan Zhuo Membrane Technology Co Ltd
Current assignee: Foshan Zhuo Membrane Technology Co Ltd
Priority date: 2019-03-04
Filing date: 2019-03-04
Publication date: 2019-10-25
Anticipated expiration: 2029-03-04

Abstract

The utility model discloses a kind of piezoelectric transducers, including pedestal, the first adhesive layer being set on the base, piezoelectric thin film layer on first adhesive layer is set, the second adhesive layer on piezoelectric thin film layer is set, mass block on second adhesive layer is set, and the shell that lid is located on pedestal, the piezoelectric thin film layer includes supporter, the first electrode being successively set on supporter, piezoelectric membrane and second electrode, the piezoelectric membrane with a thickness of 0.1-10 μm, the shell includes side wall, top, interconnecting piece and vacancy portion, the top is located at the top of pedestal, the interconnecting piece is arranged between top and mass block, the vacancy portion is located at the top of mass block, the side wall is connect with top and pedestal.The piezoelectric sensor structure of the utility model is simple, small in size, light-weight and be suitable for mass production.

Description

A kind of piezoelectric transducer

Technical field

The utility model relates to sensor technical field more particularly to a kind of piezoelectric transducers.

Background technique

Piezoelectric transducer is the sensor based on piezoelectric effect.Piezoelectric transducer can be to various dynamic forces, machinery Shock and vibration measure, and power or deformation are converted into electric signal, are widely used in the neck such as acoustics, medicine, mechanics, navigation Domain.

Lead zirconate titanate (PZT) is a kind of PbZrO₃And PbTiO₃Mixing material, have excellent piezoelectric property and dielectric special Property, therefore, PZT is most widely used piezoelectric material in existing piezoelectric transducer.Wherein, Zr/Ti proportion becomes in PZT Change or add one or two kinds of other microelements (such as antimony, tin, manganese, tungsten), performance can also change.

PZT piezoelectric acceleration sensor is one of PZT piezoelectric transducer.It is broadly divided into compression and shearing two is big Class, compression sensor have higher response frequency compared with shearing-type.Fig. 1 is that traditional uniaxial compression formula piezoelectric acceleration passes The structural schematic diagram of sensor, traditional uniaxial compression formula piezoelectric acceleration sensor includes newel 1, piezoelectric patches 2, mass block 3, pre- Pressing spring 4, fixation member 5, shell 6 and pedestal 7.

Existing piezoelectric patches 2 is piezoelectric ceramic piece, is formed by ceramic powder compacting sintering, due to the particle ratio of powder It is larger, inevitably there is gap in the piezoelectric ceramic piece being fired into, and material composition, density, there is also deviations for thickness. In order to reduce inhomogeneities, before use, need to carry out grinding process to each piezoelectric ceramic piece, but remain in the presence of uneven Property.In addition, piezoelectric ceramic piece is more crisp, especially thickness than it is relatively thin in the case where, once firmly unevenness be easy to cause breaking-up Property it is broken.It is crushed in order to prevent, the thickness of existing piezoelectric ceramic piece is generally in 0.1mm or more.Due to the intrinsic resonance frequency of device The thickness of rate and material is inversely proportional, and increases the thickness of piezoelectric ceramic piece, can reduce the resonant frequency of device, reduces the use of device The resonant frequency of frequency range, existing piezoelectric transducer only has 60kHz.

Further, since the material of each component of piezoelectric ceramic piece is different, Density Distribution is also not quite similar, and machining is deposited In error, so the position of newel is difficult to be overlapped with the mass centre of each component, to generate eccentric phenomena.

Further, the size and quality of component are increased due to the presence of newel, existing piezoelectric transducer it is general Outer diameter is in 9mm, and weight is in 5g or more, to limit the use of device.

Summary of the invention

Technical problem to be solved by the utility model is to provide a kind of piezoelectric transducer, structure is simple, it is small in size, It is light-weight and be suitable for mass production.

In order to solve the above-mentioned technical problem, the utility model provides a kind of piezoelectric transducer, including pedestal, setting the bottom of at The first adhesive layer on seat, the piezoelectric thin film layer being arranged on the first adhesive layer, the second gluing being arranged on piezoelectric thin film layer The shell that layer, the mass block being arranged on the second adhesive layer and lid are located on pedestal, the piezoelectric thin film layer include support Body, first electrode, piezoelectric membrane and the second electrode being successively set on supporter, the piezoelectric membrane with a thickness of 0.1-10 μm, the shell includes side wall, top, interconnecting piece and vacancy portion, and the top is located at the top of pedestal, the interconnecting piece setting Between top and mass block, the vacancy portion is located at the top of mass block, and the side wall is connect with top and pedestal.

As an improvement of the above scheme, the contact area of the interconnecting piece and mass block is the 20%- of mass block surface area 90%.

As an improvement of the above scheme, the vacancy portion is located at the top of mass block geometric center, the top and connection Portion is monolithic construction.

As an improvement of the above scheme, the supporter is made of the hard material for not generating charge, or by generating electricity Lotus quantity be less than piezoelectric membrane generate amount of charge hard material be made, the supporter with a thickness of 0.05-2mm.

As an improvement of the above scheme, the piezoelectric membrane by Pb, Zr, Ti, Ba, Fe, Bi, Nb, Sr, La, Mn, Co, B, One of Ni, Li, Na, K, Sn and Si are made.

As an improvement of the above scheme, the piezoelectric membrane is pzt thin film, BaTiO film, BiFeO₃Film, BaSrO₃It is thin Film, LiNbO₃Film, KNbO₃Film or LiTaO₃Film.

As an improvement of the above scheme, the first electrode and second electrode by Au, Ti, Pt, Ir, Ni, La, Ni, Ru, One of Sr, Ag, Cr, Al, Cu are made.

As an improvement of the above scheme, the mass block is made of copper, tungsten or tungsten copper.

As an improvement of the above scheme, first adhesive layer and the second adhesive layer are by silicon rubber, epoxide-resin glue, propylene One of acid esters glue and polyurethane adhesive are made.

As an improvement of the above scheme, the pedestal and shell are made of one of stainless steel, Ti, Al and Cu.

Implement the utility model, has the following beneficial effects:

1, the piezoelectric transducer of the utility model on supporter by forming piezoelectric membrane, and cooperates first electrode and Two electrodes are to form piezoelectric thin film layer, for substituting traditional piezoelectric ceramic piece, can greatly reduce the size of device, in addition, The utility model passes through the first adhesive layer and the second adhesive layer for piezoelectric thin film layer, mass block by forming piezoelectric thin film layer It is formed and is connected with substrate, do not need setting newel, it can asking to avoid the mass eccentricity of traditional compression type acceleration transducer Topic reduces mechanical part, the resonant frequency and uniformity of device is further turned up.

2, the utility model shell passes through the mutual cooperation of interconnecting piece and vacancy portion, wherein by interconnecting piece by mass block Edge compress, shell, to reduce the supercentral pressure of mass block, is reduced due to being equipped with vacancy portion in and the top of mass block Top is to piezoelectric membrane stressor layer, and reducing shell influences the resonance of piezoelectric thin film layer, to improve the resonance of piezoelectric transducer Frequency, and then increase the scope of application of piezoelectric transducer.

3, it is right under temperature change or change in shape can also to reduce adhesive layer or pedestal for the supporter of the utility model The influence of piezoelectric membrane guarantees the accuracy of measurement result.

4, compared with existing piezoelectric ceramic piece, the piezoelectric thin film layer of the utility model uses this structure of supporter, causes So that piezoelectric membrane is formed on the carrier of large area, production efficiency can not only be improved, additionally it is possible to improve piezoelectric membrane Uniformity controls the thickness error of piezoelectric membrane within ± 5%, and surface roughness adds in nm magnitude with existing machinery Work mode is compared, and the piezoelectric membrane of the utility model has having greatly improved in terms of uniformity.

5, since the piezoelectric membrane of the utility model is formed on supporter, so the thickness of the utility model piezoelectric membrane Degree can control in 0.1-10 μ m, and thickness is only the 1/10 of conventional piezoelectric potsherd thickness hereinafter, therefore can be big Width improves the intrinsic vibration frequency of device, expands the use scope of device.In addition, the thickness of the utility model piezoelectric membrane is very It is small, it is possible to reduce the error that transverse movement imports.

6, the piezoelectric thin film layer that the piezoelectric transducer of the utility model uses is cut in large-sized piezoelectric film material It cuts out, therefore the piezoelectric membrane similar performance of each small pieces, transverse dimension error can control to be measured at 1% below μm Grade, is conducive to the mass production of piezoelectric transducer.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of traditional uniaxial compression formula piezoelectric acceleration sensor；

Fig. 2 is the structural schematic diagram of the utility model piezoelectric transducer；

Fig. 3 is the first embodiment connection schematic diagram of the utility model shell and mass block；

Fig. 4 is the second embodiment connection schematic diagram of the utility model shell and mass block；

Fig. 5 is the structural schematic diagram of the utility model piezoelectric thin film layer；

Fig. 6 is the resonant frequency curve graph of the utility model interconnecting piece Yu mass block contact area and piezoelectric transducer.

Specific embodiment

It is practical new to this below in conjunction with attached drawing to keep the purpose of this utility model, technical solution and advantage clearer Type is described in further detail.

Referring to fig. 2, a kind of stable piezoelectric transducer provided by the utility model, including pedestal 1, is arranged on pedestal 1 First adhesive layer 2, the piezoelectric thin film layer 3 being arranged on the first adhesive layer 2, the second adhesive layer being arranged on piezoelectric thin film layer 3 4, the shell 6 that the mass block 5 and lid being arranged on the second adhesive layer 4 are located on pedestal 1.

Specifically, first adhesive layer 2, piezoelectric thin film layer 3, the second adhesive layer 4 and mass block 5 are arranged in 1 and of pedestal In the accommodating cavity that shell 6 is formed.

Referring to Fig. 3, the shell 6 includes side wall 61, top 62, interconnecting piece 63 and vacancy portion 64, and the top 62 is located at The top of pedestal 1, the interconnecting piece 63 are arranged between top 62 and mass block 5, and the vacancy portion 64 is located at the upper of mass block 5 Side, the side wall 61 are connect with top 62 and pedestal 1.

Specifically, the interconnecting piece 63 extends along top 62 towards mass block 5, and it is pressed in the upper of mass block 5.

Preferably, the vacancy portion 64 is located at the top of 5 geometric center of mass block.

Referring to fig. 4, the another embodiment as shell 6, the top 62 and interconnecting piece 63 are monolithic construction, described Interconnecting piece 63 is pressed in the edge of the mass block.

Referring to Fig. 5, the piezoelectric thin film layer 3 includes supporter 31, the first electrode 32 being arranged on supporter 31, setting In the piezoelectric membrane 33 in first electrode 32 and the second electrode 34 being arranged on piezoelectric membrane 33, wherein the piezoelectricity is thin Film 33 with a thickness of 0.1-10 μm.

The supporter 31 is made of hard material, in the course of work of sensor, supporter 31 do not generate charge or Person generate amount of charge be less than piezoelectric membrane generate charge number, in this way in action process, can to avoid or reduce by The introduced influence of the charge that supporter generates.Preferably, the material of the supporter 31 is Si, Al₂O₃Or SiO₂。

The supporter 31 of the utility model is for reducing adhesive layer or pedestal under temperature change or change in shape to pressure The influence of conductive film guarantees the accuracy of measurement result.Wherein, supporter 31 with a thickness of 0.05-2mm.The thickness of supporter 31 Degree is less than 0.05mm, and supporter is easily deformed in gluing fixation procedure, to influence the piezoelectric property of piezoelectric membrane；Supporter When 31 thickness is greater than 2mm, effect is no longer obvious, will increase the size and weight of device instead.Preferably, supporter 31 With a thickness of 0.1-1mm.Specifically, supporter with a thickness of 0.05mm, 0.1mm, 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm or 2mm.

It should be noted that the piezoelectric membrane 33 of the utility model is using physics or chemical deposition mode in large area It is formed on supporter 31, wherein the size of supporter 31 can be 4 cun, 6 cun or 8 cun.Specifically, magnetron sputtering can be used Method, hydro-thermal method, electrochemical process, sol-gel method, organic chemical vapor deposition, pulsed laser deposition or the injection of high pressure powder Substrate method forms the piezoelectric membrane of large area on supporter.

Compared with existing piezoelectric ceramic piece, the piezoelectric thin film layer 3 of the utility model uses this structure of supporter, causes Piezoelectric membrane 33 can be formed on the carrier of large area, can not only improve production efficiency, additionally it is possible to improve piezoelectric membrane 33 Uniformity, make piezoelectric membrane 33 thickness error control within ± 5%, surface roughness is in nm magnitude, with existing machine Tool processing method is compared, and the piezoelectric membrane of the utility model has having greatly improved in terms of uniformity.

Since the piezoelectric membrane 33 of the utility model is formed on supporter 31, so the utility model piezoelectric membrane 33 Thickness can control in 0.1-10 μ m, thickness is only conventional piezoelectric potsherd thickness 1/10 hereinafter, therefore may be used To greatly improve the intrinsic vibration frequency of device, expand the use scope of device, the vibration frequency of the utility model piezoelectric transducer Rate is up to 100kHz.Since the sensor in Fig. 1 uses thicker piezoelectric ceramic piece, transverse movement importing can be generated Error in addition, and the thickness of the utility model piezoelectric membrane 33 is very small, therefore can reduce transverse movement importing error.It is excellent Choosing, the piezoelectric membrane 33 with a thickness of 0.3-5 μm.Specifically, the piezoelectric membrane 33 with a thickness of 0.1 μm, 0.3 μm, 0.5 μm, 0.8 μm, 1 μm, 1.5 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm.

The piezoelectric membrane 33 is by Pb, Zr, Ti, Ba, Fe, Bi, Nb, Sr, La, Mn, Co, B, Ni, Li, Na, K, Sn and Si One of be made.

Preferably, the piezoelectric membrane 33 is pzt thin film, BaTiO film, BiFeO₃Film, BaSrO₃Film, LiNbO₃ Film, KNbO₃Film or LiTaO₃Film.

The piezoelectric transducer of the utility model cooperates first electrode and second by forming piezoelectric membrane on supporter Electrode is to form piezoelectric thin film layer, for substituting traditional piezoelectric ceramic piece, can greatly reduce the size of device, in addition, this Utility model by forming piezoelectric thin film layer, and by the first adhesive layer and the second adhesive layer by piezoelectric thin film layer, mass block and The problem of substrate forms connection, does not need setting newel, can be to avoid the mass eccentricity of traditional compression type acceleration transducer, Mechanical part is reduced, the resonant frequency and uniformity of device is further turned up.

Secondly, the piezoelectric membrane that the piezoelectric transducer of the utility model uses is cut into large-sized piezoelectric membrane Come, therefore the piezoelectric membrane similar performance of each small pieces, transverse dimension error can control in 1% micron dimension below, Be conducive to the mass production of piezoelectric transducer, specifically, piezoelectric membrane such as uses square cut, side length can be less than 5mm, group After dress, the weight of the utility model piezoelectric transducer can drop to 3g.

Again, the utility model shell passes through the mutual cooperation of interconnecting piece and vacancy portion, wherein by interconnecting piece by quality The edge of block compresses, and the surface of mass block, due to being equipped with vacancy portion, to reduce the supercentral pressure of mass block, reduces Cover top portion is to piezoelectric membrane stressor layer, and reducing shell influences the resonance of piezoelectric thin film layer, to improve piezoelectric transducer Resonant frequency, and then increase the scope of application of piezoelectric transducer.

Referring to Fig. 6, the contact area of the interconnecting piece and mass block plays the resonant frequency of piezoelectric transducer important It influences.Preferably, the contact area of the interconnecting piece and mass block is the 20%-90% of mass block surface area.

It should be noted that the first electrode 32 and second electrode 34 by Au, Ti, Pt, Ir, Ni, La, Ni, Ru, Sr, One of Ag, Cr, Al, Cu are made.In the other embodiments of the utility model, first electrode 32 and second electrode 34 may be used also By SrRuO₃、LaNiO₃、InTiO₃Equal oxide conductings material is made.

Wherein, the pedestal 1 is made of the metal of lightweight.Preferably, the pedestal 1 and shell 6 are by stainless steel, Ti, Al It is made with one of Cu, but not limited to this.The connector 7 is preferably elastic component.

Preferably, the mass block 5 is made of copper, tungsten or tungsten copper.First adhesive layer 2 and the second adhesive layer 4 are by silicon One or more of rubber, epoxide-resin glue, acrylic adhesive and polyurethane adhesive are made.

Above disclosed is only a kind of preferred embodiment of the utility model, certainly cannot be practical to limit with this Novel interest field, therefore equivalent variations made according to the claim of the utility model still belong to what the utility model was covered Range.

Claims

1. a kind of piezoelectric transducer, which is characterized in that including pedestal, the first adhesive layer being set on the base, be arranged first Piezoelectric thin film layer on adhesive layer, the second adhesive layer being arranged on piezoelectric thin film layer, the quality being arranged on the second adhesive layer The shell that block and lid are located on pedestal, the piezoelectric thin film layer includes supporter, the first electricity being successively set on supporter Pole, piezoelectric membrane and second electrode, the piezoelectric membrane with a thickness of 0.1-10 μm, the shell includes side wall, top, connection Portion and vacancy portion, the top are located at the top of pedestal, and the interconnecting piece is arranged between top and mass block, the vacancy portion Positioned at the top of mass block, the side wall is connect with top and pedestal.

2. piezoelectric transducer as described in claim 1, which is characterized in that the contact area of the interconnecting piece and mass block is matter The 20%-90% of gauge block surface area.

3. piezoelectric transducer as described in claim 1, which is characterized in that the vacancy portion is located at the upper of mass block geometric center Side, the top and interconnecting piece are monolithic construction.

4. piezoelectric transducer as described in claim 1, which is characterized in that the supporter is not by generating the hard material of charge It is made, or is made of the hard material that generation amount of charge is less than piezoelectric membrane generation amount of charge, the thickness of the supporter Degree is 0.05-2mm.

5. piezoelectric transducer as described in claim 1, which is characterized in that the piezoelectric membrane by Pb, Zr, Ti, Ba, Fe, Bi, One of Nb, Sr, La, Mn, Co, B, Ni, Li, Na, K, Sn and Si are made.

6. piezoelectric transducer as claimed in claim 5, which is characterized in that the piezoelectric membrane be pzt thin film, BaTiO film, BiFeO₃Film, BaSrO₃Film, LiNbO₃Film, KNbO₃Film or LiTaO₃Film.

7. piezoelectric transducer as described in claim 1, which is characterized in that the first electrode and second electrode by Au, Ti, One of Pt, Ir, Ni, La, Ru, Sr, Ag, Cr, Al, Cu are made.

8. piezoelectric transducer as described in claim 1, which is characterized in that the mass block is made of copper, tungsten or tungsten copper.

9. piezoelectric transducer as described in claim 1, which is characterized in that first adhesive layer and the second adhesive layer are by silicon rubber One of glue, epoxide-resin glue, acrylic adhesive and polyurethane adhesive are made.

10. piezoelectric transducer as described in claim 1, which is characterized in that the pedestal and shell by stainless steel, Ti, Al and One of Cu is made.