CN102279373B - Uniaxially electrostatic-driven sensor for weak magnetic field measurement - Google Patents
Uniaxially electrostatic-driven sensor for weak magnetic field measurement Download PDFInfo
- Publication number
- CN102279373B CN102279373B CN 201110195515 CN201110195515A CN102279373B CN 102279373 B CN102279373 B CN 102279373B CN 201110195515 CN201110195515 CN 201110195515 CN 201110195515 A CN201110195515 A CN 201110195515A CN 102279373 B CN102279373 B CN 102279373B
- Authority
- CN
- China
- Prior art keywords
- sensitive element
- cantilever
- gmr
- dielectric base
- gmr sensitive
- 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.)
- Active
Links
Images
Abstract
The invention provides a uniaxially electrostatic-driven sensor for weak magnetic field measurement. The sensor comprises an insulating substrate, a pair of electrostatic driving electrodes, two pairs of input and output electrodes, a giant magnetoresistive (GMR) sensitive element, two same magnetic line collectors, a micro-cantilever, and a modulated film. The insulating substrate is plated with an electrode and a shallow groove is etched on the insulating substrate. The GMR sensitive element and the two magnetic line collectors are fixed on the surface of the insulating substrate as well as the central axises of the GMR sensitive element and the two magnetic line collectors are formed into a straight line. The micro-cantilever employs a conductive silicon chip for manufacture and comprises a pedestal and a cantilever, wherein the pedestal is fixed on the insulating substrate and is connected with the cantilever and the modulated film is prepared on a lower surface of an upwarp end of the cantilever. A vertical distance from the modulated film to the GMR sensitive element is 8 to 15 micrometers. According to the sensor for weak magnetic field measurement provided in the invention, a modulation depth is great; a resolution is high; and the structure and the technology of the sensor are simple.
Description
Technical field
The present invention relates to sensor technical field, especially for the sensor of feeble signal, specifically, relate to a kind of uniaxial magnetic quantity sensor for measuring Weak magentic-field.
Background technology
Weak magentic-field is measured and all is widely used in fields such as earth-magnetic navigation, target detection, geologic prospecting, biomedicines.The sensor type that present stage measures for Weak magentic-field is more, mainly comprise fluxgate sensor, optical pumping formula Magnetic Sensor, proton formula Magnetic Sensor, optical fiber Magnetic Sensor, giant magnetic impedance Magnetic Sensor, GMR (Giant Magnetoresistive, giant magnetoresistance) Magnetic Sensor etc., wherein the GMR Magnetic Sensor is based on microelectronic technique and makes, and the Magnetic Sensor of comparing other types obviously has the characteristics such as volume is little, low in energy consumption, easy batch production.
1988, French scientist Albert Fert and Germany scientist Peter Grunberg lead separately experiment group has successively independently found the GMR effect, wherein Albert Fert experiment group study finds that the resistance value of iron-chromium multilayer film sharply changes in Weak magentic-field, and with this phenomenon called after " GMR effect ", and Peter Grunberg group has also found similar experimental phenomena in iron-chromium-three layers of iron antiferromagnet film structure.After this research for the GMR effect has just launched in high gear, and the new construction with GMR effect constantly presents, and the structure with GMR effect also is referred to as the GMR sensitive element.Along with deepening continuously of research, the magnetic field sensitivity that it is found that the GMR sensitive element is higher, its noise particularly 1/f noise is also larger, and the 1/f magnetic noise that wherein depends on the inner magnet structure can't be suppressed by the electrical modulation method of routine, and this point has limited the raising of GMR Magnetic Sensor resolving power just.
Recent years abroad has been carried out large quantity research for the problem that how effectively to suppress the 1/f noise of GMR sensitive element, and wherein using micro mechanical structure to drive the tested low frequency Weak magentic-field of thin magnetic film modulation, to suppress the technical scheme of GMR sensitive element 1/f noise the most feasible.the Alan S.Edelstein in AUS laboratory etc. has obtained 4 relevant American National patents (patent No.: US6670809 successively between 2003 to 2007, US7046002, US7185541, US7195945), described in these patents, the common feature of technical scheme is: at first magnetic line of force collector is prepared on micro mechanical structure, then utilize the static type of drive to drive micro mechanical structure and the common dither of magnetic line of force collector, the magnetic field enlargement factor of magnetic line of force collector periodically changes thereupon, be in this moment GMR sensitive element in magnetic line of force collector gap may detect after a high frequency modulated by measuring magnetic field.Though this type of technical scheme can effectively suppress the 1/f noise of GMR sensitive element, and obviously improve the low frequency magnetic field resolving power of GMR Magnetic Sensor, but its structure relative complex, manufacture craft relates to deep reaction ion etching technology and Silicon-On-Insulator technology, whole process wastes time and energy, cost is very high, and depth of modulation also lower (14% left and right), be unfavorable for further improving the magnetic field resolving power in addition.
Summary of the invention
The present invention will provide a kind of depth of modulation larger, and resolving power is higher, the simple weak magnetic measurement sensor of structural manufacturing process.
Technical scheme of the present invention is: the quiet electrically driven (operated) weak magnetic measurement sensor of a kind of single shaft comprises dielectric base, a pair of electrostatic drive electrodes, the two pairs of input and output electrodes, GMR sensitive element, two identical magnetic line of force collector, micro-cantilever, Modulated Films.Described dielectric base adopts the glass sheet of surface finish, is coated with two pairs of input and output electrodes and a pair of electrostatic drive electrodes on dielectric base; Dielectric base central authorities are etched with a shallow slot, and shallow slot one end extends to the dielectric base edge; The a certain utmost point of electrostatic drive electrodes is plated in shallow slot, and extends to the dielectric base edge, and another utmost point is electrically connected to micro-cantilever.Described GMR sensitive element is fine strip shape, and its upper face center has a horizontal gap.Each magnetic line of force collector one end has " recessed " shape groove, and " recessed " shape well width is slightly wider than GMR sensitive element.GMR sensitive element and two magnetic line of force collectors all are fixed on the insulating base surface, and GMR sensitive element two ends lay respectively in " recessed " shape groove of magnetic line of force collector, and this three of GMR sensitive element and two magnetic line of force collectors axis in line.Two pairs of input and output electrodes are connected with two pairs of input and output electrodes of GMR sensitive element respectively.Micro-cantilever adopts conductive silicon chip to make, and comprises pedestal and cantilever.Pedestal is fixed on dielectric base, pedestal connecting cantilever, cantilever be positioned at shallow slot be coated with electrostatic drive electrodes directly over, have some damping holes on cantilever; Cantilever free end upwarps, and upwarps end and has two mating holes, upwarps the Modulated Films that is prepared with the high magnetic permeability soft magnetic material between two mating holes of end lower surface; Modulated Films is over against the gap of GMR sensitive element, and the shape of Modulated Films is identical with the surface configuration in gap, and Modulated Films and GMR sensitive element vertical range are determined according to actual needs, usually at 8～15 microns.
the invention has the beneficial effects as follows: the modulation system that adopts Modulated Films to vibrate directly over the GMR sensitive element, can make the Oscillation Amplitude of Modulated Films relatively large, therefore the depth of modulation that obtains is large (simulation results show is greater than 40%), it is high-frequency alternating magnetic field at GMR sensitive element place that modulation by Modulated Films makes faint D.C. magnetic field, the 1/f noise that has suppressed the GMR element, by adopting magnetic line of force collector to make Weak magentic-field obtain amplification at GMR sensitive element place, thereby the Magnetic Sensor measurement resolution is greatly improved (simulation results show has improved two orders of magnitude), micro cantilever structure is simple, and is easily manufactured, effectively reduces the manufacturing of the fiber grating sensors cost.
Description of drawings
Fig. 1 is the structural representation that the single shaft static that provides of a certain embodiment of the present invention drives the weak magnetic measurement sensor;
Fig. 2 is the dielectric base schematic diagram in a certain embodiment of the present invention;
Fig. 3 is bar shaped magnetic line of force collector in a certain embodiment of the present invention and the package assembly schematic diagram of GMR sensitive element;
Fig. 4 (a) is the vertical view of micro-cantilever in a certain embodiment of the present invention;
Fig. 4 (b) is the upward view of micro-cantilever in a certain embodiment of the present invention;
Fig. 4 (c) is the side view of micro-cantilever in a certain embodiment of the present invention.
The 1-pedestal, 2-cantilever, 3-Modulated Films, 4-step one, 5-damping hole, 6-step two, the 7-mating holes, 8-dielectric base, 9-shallow slot, 11-a and 11-b-electrostatic drive electrodes pair, 12-a and 12-b-input and output electrode to one, 13-a and 13-b-input and output electrode to two, the 14-GMR sensitive element, 15-magnetic line of force collector, 16-gap, 17-micro-cantilever.
Embodiment
The invention will be further described below in conjunction with accompanying drawing.
Fig. 1 is the structural representation that the single shaft static that provides of a certain embodiment of the present invention drives the weak magnetic measurement sensor.As shown in the figure, this embodiment comprises dielectric base 8, a pair of electrostatic drive electrodes 11-a and 11-b, the two couples of input and output electrode 12-a and 12-b, 13-a and 13-b, GMR sensitive element 14, two identical magnetic line of force collectors 15, micro-cantilever 17, Modulated Films 3 (seeing Fig. 4).Described dielectric base 8 adopts the glass sheet of surface finish, is coated with two couples of input and output electrode 12-a and 12-b, 13-a and 13-b on glass sheet, a pair of electrostatic drive electrodes 11-a and 11-b; Dielectric base 8 central authorities are etched with a shallow slot 9, and shallow slot one end extends to the dielectric base edge; The 11-b utmost point of electrostatic drive electrodes is plated in shallow slot 9, and the 11-a utmost point of electrostatic drive electrodes is electrically connected to micro-cantilever 17.Described GMR sensitive element 14 is fine strip shape, and its upper face center has a horizontal gap 16 (seeing Fig. 3); Each magnetic line of force collector 15 1 end has " recessed " shape groove, and " recessed " shape well width is than GMR sensitive element 14 slightly wide (seeing Fig. 3); GMR sensitive element 14 and two magnetic line of force collectors 15 are all fixed (as adopting epoxide-resin glue bonding) on insulating base 8 surfaces, and GMR sensitive element 14 two ends lay respectively in " recessed " shape groove of a magnetic line of force collector 15, and this three of GMR sensitive element 14 and two magnetic line of force collectors 15 (sees Fig. 3) in the axis in line.Two pairs of input and output electrodes are connected with two pairs of input and output electrodes of GMR sensitive element 14 respectively.The pedestal 1 of micro-cantilever 17 fixing (as with epoxy gas resin glue bonding or low-temperature bonding) on dielectric base 8, pedestal 1 connecting cantilever 2, cantilever 2 is directly over shallow slot 9; Have some damping holes 5 (seeing Fig. 4 (b)) on cantilever 2; Cantilever 2 free ends upwarp (seeing Fig. 4 (a)), and namely the end away from pedestal upwarps; Upwarp end and have two mating holes 7, upwarp the Modulated Films 3 (seeing Fig. 4 (c)) that is prepared with the preparation of high magnetic permeability soft magnetic material between two mating holes 7 of end lower surface; Modulated Films 3 be positioned at GMR sensitive element 14 gap 16 directly over, the shape of Modulated Films 3 is identical with the surface configuration in gap 16, Modulated Films 3 with GMR sensitive element 14 vertical ranges as required usually at 8～15 microns.
Fig. 2 is the dielectric base schematic diagram in a certain embodiment of the present invention.As shown in the figure: dielectric base 8 adopts the polished glass sheet to make, and its profile is not limited to rectangle shown in Figure 2; The central photoetching corrosion of dielectric base 8 has shallow slot 9, shape is not limited to " T " font shown in Figure 2, the 11-b utmost point that can hold electrostatic drive electrodes in shallow slot 9 namely meets the demands, corrosive liquid is selected the glass erosion liquids such as diluted hydrofluoric acid, corrosion depth is come definite according to required electrostatic force size, the larger corrosion depth of required electrostatic force is more shallow; The 11-a utmost point of electrostatic drive electrodes is comprised of two small electrodes; Input and output electrode is shown in Figure 2 to shape and the neither limit of particular location of 12-a and 12-b, 13-a and 13-b, satisfies can be electrically connected to GMR sensitive element 14 to get final product; On dielectric base 8, all electrode pairs adopt first sputter (or vacuum evaporation, plating etc.) conductive film layer (gold, aluminium, copper etc.), then the technique of photoetching corrosion prepares moulding.
Fig. 3 is magnetic line of force collector in a certain embodiment of the present invention and the package assembly schematic diagram of GMR sensitive element.As shown in the figure: GMR sensitive element 14 adopts commercially available prod (as the AA002-02 of NVE), and GMR sensitive element 14 is slice shape, and upper face center has a horizontal gap 16; Magnetic line of force collector 15 is made (as NiFe, CoZrNb etc.) by the high magnetic permeability soft magnetic material, and it is shaped as rectangle (or trapezoidal etc.), and an end has " recessed " shape groove; GMR sensitive element 14 is between two magnetic line of force collectors 15, and GMR sensitive element 14 two ends are embedded in " recessed " shape groove of two magnetic line of force collectors 15, and this three axis in line.
Fig. 4 (a)～Fig. 4 (c) is vertical view, upward view and the side view of micro-cantilever in a certain embodiment of the present invention.As shown in the figure: micro-cantilever 17 is made by miromaching by silicon chip, comprises pedestal 1, cantilever 2.Pedestal 1 is not limited only to " recessed " shape, the arbitrary shape that satisfies supporting cantilever 2 all can, pedestal 1 is connected with cantilever 2; Cantilever 2 has several damping holes 5 along its length, and the damping hole number can be 3～5; Cantilever 2 free ends upwarp, and upwarping the end place has step 6, and cantilever 2 upwarps end and has two mating holes 7; Cantilever 2 upwarps between two mating holes 7 of end lower surface and is prepared with Modulated Films 3; Modulated Films 3 is made (as NiFe, CoZrNb etc.) by the high magnetic permeability soft magnetic material, be rectangle along cantilever 2 axis directions, the preparation method first upwarps the end lower surface at cantilever 2 to electroplate (or vacuum evaporation, sputter etc.) one deck high magnetic permeability soft magnetic material film, then by the lithography corrosion process moulding.
During use, the exciting circuit of a pair of electrostatic drive electrodes with the outside is connected, makes semi-girder be operated in resonant condition; A pair of input and output electrode is connected with outside constant voltage source (or current source), and a pair of input and output electrode is connected with outer detecting circuit, can obtain the size of low-intensity magnetic field according to the measured value of outer detecting circuit.
Claims (2)
1. quiet electrically driven (operated) weak magnetic measurement sensor of single shaft, comprise dielectric base (8), a pair of electrostatic drive electrodes (11-a, 11-b), two pairs of input and output electrodes (12-a, 12-b, 13-a, 13-b), GMR sensitive element (14), two identical magnetic line of force collectors (15), micro-cantilever (17), Modulated Films (3), it is characterized in that, described dielectric base (8) adopts the glass sheet of surface finish, is coated with two pairs of input and output electrodes and a pair of electrostatic drive electrodes on dielectric base (8); Dielectric base (8) central authorities are etched with a shallow slot (9), and shallow slot (9) one ends extend to dielectric base (8) edge; The a certain utmost point of electrostatic drive electrodes (11-a, 11-b) is plated in shallow slot (9), and extends to dielectric base (8) edge, and another utmost point is electrically connected to micro-cantilever (17); Described GMR sensitive element (14) is fine strip shape, and its upper face center has a horizontal gap (16); Each magnetic line of force collector (15) one end has " recessed " shape groove, and " recessed " shape well width is slightly wider than GMR sensitive element (14); GMR sensitive element (14) and two magnetic line of force collectors (15) all are fixed on dielectric base (8) surface, and GMR sensitive element (14) two ends lay respectively in " recessed " shape groove of magnetic line of force collector (15), and this three of GMR sensitive element (14) and two magnetic line of force collectors (15) axis in line; Two pairs of input and output electrodes are connected with two pairs of input and output electrodes of GMR sensitive element (14) respectively; Micro-cantilever (17) adopts conductive silicon chip to make, and comprises pedestal (1) and cantilever (2); Pedestal (1) is fixed on dielectric base (8), pedestal (1) connecting cantilever (2), cantilever (2) be positioned at shallow slot (9) be coated with electrostatic drive electrodes directly over, have some damping holes (5) on cantilever (2); Cantilever (2) free end upwarps, and the free end that upwarps has two mating holes (7), is prepared with the Modulated Films (3) of high magnetic permeability soft magnetic material between two mating holes of the free end lower surface that upwarps (7); Modulated Films (3) is over against the gap of GMR sensitive element (14), and the shape of Modulated Films (3) is identical with the surface configuration in the gap (16) of GMR sensitive element (14).
2. the quiet electrically driven (operated) weak magnetic measurement sensor of single shaft according to claim 1, is characterized in that Modulated Films (3) and the scope of GMR sensitive element (14) vertical range are 8 to 15 microns.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110195515 CN102279373B (en) | 2011-07-13 | 2011-07-13 | Uniaxially electrostatic-driven sensor for weak magnetic field measurement |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110195515 CN102279373B (en) | 2011-07-13 | 2011-07-13 | Uniaxially electrostatic-driven sensor for weak magnetic field measurement |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102279373A CN102279373A (en) | 2011-12-14 |
| CN102279373B true CN102279373B (en) | 2013-06-12 |
Family
ID=45104929
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110195515 Active CN102279373B (en) | 2011-07-13 | 2011-07-13 | Uniaxially electrostatic-driven sensor for weak magnetic field measurement |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102279373B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103116144B (en) * | 2013-01-22 | 2015-01-14 | 中国人民解放军国防科学技术大学 | Z-direction magnetic field sensor with magnetic orbit structure |
| CN103116143B (en) * | 2013-01-22 | 2015-01-14 | 中国人民解放军国防科学技术大学 | Integrated high-accuracy triaxial magnetic sensor |
| CN106443525B (en) * | 2016-11-17 | 2019-07-19 | 中国科学院上海微系统与信息技术研究所 | Torsional mode micro-mechanical magnetic field sensor and preparation method thereof |
| CN106646278B (en) * | 2016-12-09 | 2019-05-24 | 中国人民解放军国防科学技术大学 | A kind of low noise MEMS preamplifier part using high resolution detection of magnetic field |
| CN107894577B (en) * | 2017-10-27 | 2019-11-29 | 中国人民解放军国防科技大学 | Weak magnetic sensor for inhibiting 1/f noise by regulating and controlling magnetic moment by electric field and application method thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6670809B1 (en) * | 2000-08-18 | 2003-12-30 | The United States Of America As Represented By The Secretary Of The Army | Magnetic sensor with modulating flux concentrator having minimized air resistance for 1/f noise reduction |
| US7005958B2 (en) * | 2002-06-14 | 2006-02-28 | Honeywell International Inc. | Dual axis magnetic sensor |
| EP2017619A1 (en) * | 2007-07-20 | 2009-01-21 | Koninklijke Philips Electronics N.V. | Magnetic sensor device |
| WO2010122919A1 (en) * | 2009-04-22 | 2010-10-28 | アルプス電気株式会社 | Magnetic sensor |
-
2011
- 2011-07-13 CN CN 201110195515 patent/CN102279373B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN102279373A (en) | 2011-12-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102353913B (en) | Measuring transducer driven by monoaxial piezoelectricity for low-intensity magnetic field | |
| CN103323794B (en) | GMR-MEMS integrated weak magnetic sensor adopting plane micro-coil | |
| CN106154186B (en) | Surface acoustic wave magnetic sensor and preparation method thereof | |
| CN102279373B (en) | Uniaxially electrostatic-driven sensor for weak magnetic field measurement | |
| US8587300B2 (en) | Magneto-impedance sensor element and method for producing the same | |
| CN101937063B (en) | Magnetic field sensor | |
| CN103033770A (en) | Giant magneto-impedance effect two-dimensional magnetic field sensor | |
| CN102914394B (en) | MEMS (Micro Electro Mechanical System) giant magneto-resistance type high pressure sensor | |
| CN103116144B (en) | Z-direction magnetic field sensor with magnetic orbit structure | |
| US7759933B2 (en) | Magnetic amplification device comprising a magnetic sensor with longitudinal sensitivity | |
| CN101475139A (en) | MEMS horizontal resonant vibration type magnetometer | |
| CN112379315B (en) | Weak direct-current magnetic field measuring method suitable for magnetoelectric coupling sensor | |
| CN101907690A (en) | Miniaturized amorphous magnetically soft alloy magnetic core solenoid flux gate sensor | |
| CN202853817U (en) | MEMS tunnel magnetic resistance height pressure transducer | |
| CN201935997U (en) | Magnetic field sensor chip | |
| CN110068318A (en) | A kind of tunnel magnetoresistive microthrust test device based on snakelike hot-wire coil | |
| CN202853815U (en) | MEMS colossal magneto-resistance type height pressure transducer | |
| CN104614690A (en) | Micro-array type fluxgate sensor | |
| CN113008419A (en) | Magneto-resistance type integrated stress sensor and preparation method and application thereof | |
| CN102928132B (en) | Tunnel reluctance pressure transducer | |
| CN103217228B (en) | Temperature sensor based on capacitive micromachined ultrasonic transducer (CMUT) and preparation and application method of temperature sensor | |
| CN115856725B (en) | magnetic sensor | |
| CN113567898B (en) | Low-frequency MEMS (micro-electromechanical systems) magneto-resistance sensor with magneto-resistance motion modulation | |
| CN110286338A (en) | Magnetic field modulation structure suitable for integral type triaxial magnetic sensor | |
| CN215340279U (en) | MEMS (micro-electromechanical system) magnetoresistive sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |