CN103033770A - Giant magneto-impedance effect two-dimensional magnetic field sensor - Google Patents
Giant magneto-impedance effect two-dimensional magnetic field sensor Download PDFInfo
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- CN103033770A CN103033770A CN 201110300794 CN201110300794A CN103033770A CN 103033770 A CN103033770 A CN 103033770A CN 201110300794 CN201110300794 CN 201110300794 CN 201110300794 A CN201110300794 A CN 201110300794A CN 103033770 A CN103033770 A CN 103033770A
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Abstract
The invention relates to a giant magneto-impedance effect two-dimensional magnetic field sensor and belongs to the technical field of sensors. The sensor is composed of two orthogonal giant magneto-impedance effect magneto-dependent sensors 2 and 3 and an integrated circuit signal processing module 4. Each magneto-dependent sensor 2 or 3 is composed of an amorphous thin belt 4, a signal collection coil 5 with the thin belt as a magnetic core, an insulation filling material 6, a copper wire 7 at two ends and an electrode pin 8. An anisotropic filed of the thin belt of each sensor is in the width direction and is in linear or winding geometrical shape, and the sensors are manufactured by a micro electromechanical system (MEMS). When the sensors work, the signal processing module provides 0.1-100MHz high frequency alternating current signals or 0.1ns pulse signals flowing through the magnetic core, and the signal collection coil is used for sensing reaction of the magnetic core to an external magnetic field. Due to the fact that the magneto-dependent sensors have maximum sensitivity on magnetic fields in the line length direction, magnetic field components in a chip plane in the line length direction can be measured respectively to determine direction and size of the magnetic fields in the plane. The giant magneto-impedance effect two-dimensional magnetic field sensor can serve as an electronic compass to determine gesture of vehicles, mobile phones and the like, and has the advantages of being small in size, high in reaction sensitivity, high in response speed and low in power consumption.
Description
What the present invention relates to is a kind of magnetic-field measurement device, and specifically a kind of giant magnetoresistance effect two-dimensional magnetic field sensor belongs to sensor technical field.
Technical background
The accurate measurement in magnetic field is the ultimate principle of digital compass for the position of determining electronic equipment and orientation spatially, with respect to the GPS GPS, has price low, the advantage such as easy to use, therefore be widely used in various mobile devices such as mobile phone, automobile, notebook computer etc.Magneto-dependent sensor has consisted of the important component part of electronic guide needle system, common magneto-dependent sensor comprises the Hall Hall element, although can process by semiconductor technology, and size is less, but, it exists a little less than the amplitude output signal, and sensitivity is lower, and easily is subjected to the impact of temperature.Magnetoresistive transducer, novel silicon base magneto-dependent sensor AMR anisotropic magnetoresistive sensor can adopt the preparation of micro-electromechanical system (MEMS) technology, but AMR change rate of magnetic reluctance size only has 2%-4%, and its magnetic field sensitivity is less than 1%/Oe.GMR giant magneto-resistance sensor change rate of magnetic reluctance can reach more than 80%, also can obtain higher signal output, but driving magnetic field very high (more than the 300Oe), its magnetic field sensitivity is at 1%-2%/Oe.The giant magnetic impedance sensor is a kind of novel magneto-dependent sensor, obtain in recent years broad research, its principle is to utilize magnetically soft alloy material to show giant magnetic impedance (Giant magneto-impedance under very little D.C. magnetic field effect, referred to as GMI) effect, namely when there is subtle change in magnetic field, will cause soft magnetic material AC impedance great variety.People have obtained very large giant magnetoresistance effect in film, multilayer film, band and the silk material of amorphous and nano crystal material preparation, its magnetic field sensitivity reaches 2%-300%/Oe, than AMR and high 1 to 2 order of magnitude of GMR sensor, be 10-100 times of hall device.And the GMI sensor has the advantages such as high sensitivity, fast response time, volume be little, utilize this high sensitivity characteristic of material, various magnetic switchs, magneto-dependent sensor, displacement transducer, angular transducer etc. can be made, the industry-by-industries such as auto industry, machinery, communications and transportation, security personnel, electric power, automatically control, Aero-Space can be widely used in.Being very suitable for preparing is dimension magnetic field sensor for digital compass.
Find by literature search, described among the US Patent No. 6831457B2 of Japan Aichi Micro Intelligent corporation company and planted two-dimentional giant magnetoresistance effect magnetic field sensor, adopt amorphous wire to be used as the sensitive material of magnetic field sensor, and prepared around the inductive coil of amorphous wire and measure amorphous wire to the reaction signal in magnetic field, by the giant magneto-impedance effect sensor perpendicular array is come the measurement plane two-dimensional magnetic field.Because amorphous wire generally prepares by drawing process, its diameter is in the 10-50 micrometer range, although its length can reach the millimeter in addition centimetre, can't be compatible mutually with semiconducter process, therefore in the process of preparation sensor, can only realize its location and processing by artificial or mechanically operated method.Secondly on the technique of preparation induction of signal coil, the elongated slot that needs again working depth on the substrate to reach 50 microns holds and amorphous wire is realized the location, and amorphous wire need to be wrapped up silica gel or epoxy insulate, although its inductive coil also can adopt the semiconductor technologies such as photoetching to process, but because semiconductor technology generally realizes based on the method for plane machining, therefore its method for making exists cost of manufacture higher, the characteristics that finished product is low, thereby increased production cost, the size of its processing and the accuracy of position are lower, will form adverse influence to measuring-signal.In contrast to this; its thickness of amorphous soft magnet strip is generally in the 20-30 micrometer range; has large contact area; therefore can stick on the substrate by epoxy resin, then by the protection of mask material film, the techniques such as employing photoetching are opened corrosion window; by semiconducter process such as dry method or wet methods; process, not only can accurately control its size and relative orientation, and can obtain more complicated shape as tortuous or spiral-shaped.In addition its insulation course and also can process by semiconductor technologies such as spin-on polyimide film, abrasive disc, plating around inductive coil, therefore in the processing of sensor, can accomplish fully compatible mutually with semiconductor technology, can realize large-scale manufacturing, thereby reduce its manufacturing cost.Therefore, this project adopts soft magnetic amorphous soft magnetic ribbon as the sensitive material of giant magneto-impedance effect sensor, and comprise magnetic-sensitive material and around the two-dimensional magnetic field detector of its outer magnetic test coil, wire and pin by adopting the micro-electromechanical system (MEMS) technology to prepare two, to be greatly improved in manufacturing cost and workmanship, and will improve that it is accurate, sensitivity and reliability.
Summary of the invention
Content of the present invention has been to propose a kind of new scheme of two-dimensional magnetic field sensor design and manufacturing, a kind of two-dimensional magnetic field sensor based on micro-electromechanical system (MEMS) technology and soft magnetic amorphous strip giant magnetoresistance effect is provided, adopt the MEMS technology in the magnetosensitive unit of two amorphous thin ribbons of substrate making quadrature and be looped around its three-dimensional spiral line circle on every side, insulation course and corresponding wire and electrode pin, and cooperate the integrated circuit (IC) module to realize coming the interior measurement along two magneto-dependent sensor direction magnetic-field components of measurement plane by to the signal excitation of two magneto-dependent sensors and the collection of magnetic field induction signal.
The present invention is achieved through the following technical solutions, and the present invention is by upper two the giant magnetoresistance effect magneto-dependent sensors of substrate (1) (2) and (3), and the integrated circuit control module (4) in sensor centre position forms.
Described giant magnetoresistance effect magneto-dependent sensor (2) is by amorphous thin ribbon magnetic core (5), and be wound in its peripheral induced signal and gather coil (6), insulation filling material (7), and the exciting current electrode (8) at two ends, electrode signal acquisition (9) and respective wire (10) form.
Described substrate (1) is glass or silicon materials;
Described amorphous thin ribbon magnetic core (5) can be the materials such as Fe base noncrystal alloy material such as FeSiBNbCuCr, Co base noncrystal alloy material such as CoFeSiB;
Described amorphous thin ribbon magnetic core (5) has along the anisotropy field of amorphous thin ribbon Width;
Described induced signal collection coil (6), exciting current electrode (8), electrode signal acquisition (9), wire (10) material are Cu;
Described insulation filling material (7) is polyimide;
Described giant magnetoresistance effect magneto-dependent sensor (2) be positioned at glass or silicon chip (1) above;
Described sensor excitation signal is sine or pulse signal;
The present invention compared with prior art has following useful effect:
(1) the present invention adopts the MEMS technology to realize the integrated processing and manufacturing of amorphous thin ribbon magnetic core, signals collecting coil, insulation filling material and wire, pin, is easy to realize large-scale production, reduces manufacturing cost;
(2) the present invention adopts the MEMS technology to make magneto-dependent sensor, can realize that size sensor and precision are very accurate, has guaranteed the repeatability of properties of sample;
(3) the present invention adopts the pick-up transducers of the three-dimensional spiral line pipe that is surrounded on magneto-dependent sensor to the signal of magnetic-field measurement, with respect to the both end voltage of direct measurement magneto-dependent sensor, has higher magnetic field sensitivity;
Description of drawings
Fig. 1 is the top view of giant magnetoresistance effect two-dimensional magnetic field sensor of the present invention.
Wherein: 1 is substrate, and 2,3 is the giant magnetic impedance sensor of quadrature, and 4 is the integrated circuit signal processing module, and 5 is the signals collecting coil, and 6 are the Cu lead-in wire, and 7 is signals collecting coil signal pin.
Fig. 2 is the cross sectional view in two-dimentional strong magnetic impedance magnetic field sensor of the present invention 2,3.
Wherein: 1 is substrate, and 5 is soft magnetic amorphous strip, and 6 is the signals collecting coil, and 9 is insulation filling material
Embodiment
Below in conjunction with accompanying drawing concrete structure of the present invention is further described.
Shown in Fig. 1-2, the present invention is by two giant magnetic impedance magneto-dependent sensors 2 on the substrate 1 and 3, and integrated circuit signal processing module 4 forms; Described giant magnetic impedance two-dimensional magnetic field sensor 2 and 3 is by soft magnetic amorphous strip 4, signals collecting coil 5 and insulation filling material 6, and wire 7 signal pins 8 form;
Described soft magnetic amorphous strip 4 is positioned over the axial location of signals collecting spool 5;
The anisotropy field of described soft magnetic amorphous strip is the Width along strip;
Described integrated circuit signal processing module 4 is used for the pumping signal of soft magnetic amorphous strip 5 and the signal of signals collecting coil 5 receives and processes, and finishes the measurement of two field signal components and synthetic.
Claims (12)
1. giant magnetic impedance two-dimensional magnetic field sensor, it is characterized in that, giant magnetoresistance effect magneto-dependent sensor 2 and 3 by two quadratures on the substrate 1, and integrated circuit signal processing module 4 forms, magneto-dependent sensor 2 and 3 is two magnetic-field components in measurement plane magnetic fields respectively, and integrated circuit signal processing module 4 is processed for generation of the signal pumping signal of magneto-dependent sensor and the corresponding signal that gathers its external magnetic field and synthesized;
2. such as right 1 described giant magnetoresistance effect magnetic field sensor 2 and 3, it is characterized in that, sensor is by soft magnetic amorphous strip 5, signals collecting spool coil 6, and insulation filling material 7, wire 8, and electrode signal acquisition 9 forms;
3. such as right 1 described giant magnetoresistance effect magnetic field sensor 2 and 3, it is characterized in that, by high frequency ac signal or pulse signal, when external magnetic field is arranged, measure the intensity of external magnetic field by the variation of measuring-signal collection coil 6 two ends induced signals in the amorphous thin ribbon 5;
4. such as right 1 described giant magnetoresistance effect magnetic field sensor 2 and 3, it is characterized in that, the high frequency ac signal frequency is 0.1-100MHz, and the pulse signal pulsewidth is 0.1ns;
5. be Width along lines such as the anisotropy field of right 3 described soft magnetic amorphous strips 4;
6. be Fe base non-crystalline material such as FeSiBNbCu or Co base noncrystal alloy material such as CoFeSiB material such as right 3 described soft magnetic amorphous strips 4.
7. be shaped as length strip, zigzag multi-turn shape etc. such as right 3 described soft magnetic amorphous thin-band materials 4;
8. the magnetic field peak response direction such as right 3 described soft magnetic amorphous strips 4 is along the lines length direction;
9. can be the silicon chip of glass, surface oxidation, the materials such as potsherd such as right 1 described substrate;
10. such as right 2 described giant magnetoresistance effect magnetic field sensors 2 and 3, it is characterized in that, its packing material is polyimide 9, and signals collecting coil method 6 is Cu.
11. such as right 1 described giant magnetoresistance effect magnetic field sensor 2 and 3, it is characterized in that, sensor preparation technology is the micro-electromechanical system (MEMS) technology, its manufacturing process is as follows
A is sputter one deck Cr/Cu Seed Layer on substrate
B, electroplates Cu and forms bottom coil as mold with photoresist
C is take photoresist as mold, and Cu post in the middle of electroplating goes Seed Layer
D spin-on polyimide colloid, hot setting
E machinery abrasive disc association reaction ion etching technology so that the Cu post spill
F adopts the gluing note amorphous thin ribbon of epoxy resin, and as mask material, the wet etching strip obtains magnetic core with photoresist
G sputtering seed layer, and electroplate the Cu pillar, go Seed Layer
The h spin-on polyimide is solidified, the ion etching of mechanical abrasive disc association reaction so that the Cu post spill
I sputtering seed layer as mold, is electroplated upper coil with photoresist
12. such as right 1 described non-crystalline thin-band material, it is characterized in that the magnetic field anisotropy is for adopting magnetic-field annealing to realize at the 300-400 degree.
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| CN103983924A (en) * | 2014-05-28 | 2014-08-13 | 哈尔滨电机厂有限责任公司 | Method for measuring magnetic induction intensity of two-dimensional magnetic field |
| CN104614690A (en) * | 2014-12-18 | 2015-05-13 | 哈尔滨理工大学 | Micro-array type fluxgate sensor |
| CN106133491A (en) * | 2014-03-28 | 2016-11-16 | 日立金属株式会社 | Torque sensor soft magnetic member, use the torque sensor of these parts |
| CN107015174A (en) * | 2017-04-18 | 2017-08-04 | 北京理工大学 | A kind of amorphous wire GMI Magnetic Sensors and preparation method thereof |
| CN107741576A (en) * | 2017-09-14 | 2018-02-27 | 北京理工大学 | A kind of miniature amorphous wire GMI Magnetic Sensors and its processing method |
| CN108072851A (en) * | 2016-11-16 | 2018-05-25 | Tdk株式会社 | Magnetic Sensor inductance element and the Magnetic Sensor for possessing it |
| CN108872889A (en) * | 2018-06-07 | 2018-11-23 | 中国船舶重工集团公司第七二五研究所 | A kind of giant magnetoresistance effect magneto-dependent sensor and preparation method |
| CN109782047A (en) * | 2019-02-26 | 2019-05-21 | 中国科学院宁波材料技术与工程研究所 | A kind of direct amplifier system current sensor based on amorphous nano-crystalline abnormal shape magnetic core |
| CN110907868A (en) * | 2019-12-13 | 2020-03-24 | 中国人民解放军国防科技大学 | Giant magneto-impedance sensor probe excitation and signal acquisition synchronization system and giant magneto-impedance sensor |
| CN111121741A (en) * | 2019-12-17 | 2020-05-08 | 湖北麦格森斯科技有限公司 | Electronic compass without inclination angle compensation |
| CN111722022A (en) * | 2020-05-09 | 2020-09-29 | 上海达铭科技有限公司 | Cable path detection method based on weak magnetic signal measurement |
| CN113253162A (en) * | 2021-06-18 | 2021-08-13 | 上海交通大学 | Micro-electro-mechanical system fluxgate geomagnetic tensor sensing chip |
| CN114101016A (en) * | 2021-11-04 | 2022-03-01 | 之江实验室 | Magnetic control flexible ultrasonic transducer |
| CN114509563A (en) * | 2022-04-18 | 2022-05-17 | 合肥工业大学 | Giant magnetoresistance sensor combined with microfluidic technology, and manufacturing method and application thereof |
| CN117148232A (en) * | 2023-10-31 | 2023-12-01 | 清华大学 | Amorphous microfilament two-dimensional space magnetic field detection probe and magnetic field detection method |
| CN117316617A (en) * | 2023-11-29 | 2023-12-29 | 兰州大学 | GMI sensor probe, U-shaped composite structure magnetic core thereof and preparation method |
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2011
- 2011-10-09 CN CN 201110300794 patent/CN103033770A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106133491A (en) * | 2014-03-28 | 2016-11-16 | 日立金属株式会社 | Torque sensor soft magnetic member, use the torque sensor of these parts |
| CN103983924A (en) * | 2014-05-28 | 2014-08-13 | 哈尔滨电机厂有限责任公司 | Method for measuring magnetic induction intensity of two-dimensional magnetic field |
| CN104614690A (en) * | 2014-12-18 | 2015-05-13 | 哈尔滨理工大学 | Micro-array type fluxgate sensor |
| CN104614690B (en) * | 2014-12-18 | 2018-03-02 | 哈尔滨理工大学 | A kind of miniature array fluxgate sensor |
| CN108072851A (en) * | 2016-11-16 | 2018-05-25 | Tdk株式会社 | Magnetic Sensor inductance element and the Magnetic Sensor for possessing it |
| CN107015174A (en) * | 2017-04-18 | 2017-08-04 | 北京理工大学 | A kind of amorphous wire GMI Magnetic Sensors and preparation method thereof |
| CN107741576A (en) * | 2017-09-14 | 2018-02-27 | 北京理工大学 | A kind of miniature amorphous wire GMI Magnetic Sensors and its processing method |
| CN108872889B (en) * | 2018-06-07 | 2021-05-18 | 中国船舶重工集团公司第七二五研究所 | Giant magneto-impedance effect magneto-dependent sensor and preparation method thereof |
| CN108872889A (en) * | 2018-06-07 | 2018-11-23 | 中国船舶重工集团公司第七二五研究所 | A kind of giant magnetoresistance effect magneto-dependent sensor and preparation method |
| CN109782047A (en) * | 2019-02-26 | 2019-05-21 | 中国科学院宁波材料技术与工程研究所 | A kind of direct amplifier system current sensor based on amorphous nano-crystalline abnormal shape magnetic core |
| CN110907868A (en) * | 2019-12-13 | 2020-03-24 | 中国人民解放军国防科技大学 | Giant magneto-impedance sensor probe excitation and signal acquisition synchronization system and giant magneto-impedance sensor |
| CN110907868B (en) * | 2019-12-13 | 2022-09-02 | 中国人民解放军国防科技大学 | Giant magneto-impedance sensor probe excitation and signal acquisition synchronization method and system and giant magneto-impedance sensor |
| CN111121741A (en) * | 2019-12-17 | 2020-05-08 | 湖北麦格森斯科技有限公司 | Electronic compass without inclination angle compensation |
| CN111722022A (en) * | 2020-05-09 | 2020-09-29 | 上海达铭科技有限公司 | Cable path detection method based on weak magnetic signal measurement |
| CN113253162A (en) * | 2021-06-18 | 2021-08-13 | 上海交通大学 | Micro-electro-mechanical system fluxgate geomagnetic tensor sensing chip |
| CN113253162B (en) * | 2021-06-18 | 2022-04-26 | 上海交通大学 | Micro-electro-mechanical system fluxgate geomagnetic tensor sensing chip |
| CN114101016A (en) * | 2021-11-04 | 2022-03-01 | 之江实验室 | Magnetic control flexible ultrasonic transducer |
| CN114101016B (en) * | 2021-11-04 | 2022-08-23 | 之江实验室 | Magnetic control flexible ultrasonic transducer |
| CN114509563A (en) * | 2022-04-18 | 2022-05-17 | 合肥工业大学 | Giant magnetoresistance sensor combined with microfluidic technology, and manufacturing method and application thereof |
| CN117148232A (en) * | 2023-10-31 | 2023-12-01 | 清华大学 | Amorphous microfilament two-dimensional space magnetic field detection probe and magnetic field detection method |
| CN117148232B (en) * | 2023-10-31 | 2024-01-02 | 清华大学 | Amorphous microfilament two-dimensional space magnetic field detection probe and magnetic field detection method |
| CN117316617A (en) * | 2023-11-29 | 2023-12-29 | 兰州大学 | GMI sensor probe, U-shaped composite structure magnetic core thereof and preparation method |
| CN117316617B (en) * | 2023-11-29 | 2024-01-26 | 兰州大学 | GMI sensor probe, U-shaped composite structure magnetic core thereof and preparation method |
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Application publication date: 20130410 |