WO2021083137A1 - 一种基于电隔离磁阻应力敏感元件的氢气传感器 - Google Patents

一种基于电隔离磁阻应力敏感元件的氢气传感器 Download PDF

Info

Publication number
WO2021083137A1
WO2021083137A1 PCT/CN2020/123946 CN2020123946W WO2021083137A1 WO 2021083137 A1 WO2021083137 A1 WO 2021083137A1 CN 2020123946 W CN2020123946 W CN 2020123946W WO 2021083137 A1 WO2021083137 A1 WO 2021083137A1
Authority
WO
WIPO (PCT)
Prior art keywords
layer
stress
hydrogen
sensing unit
free layer
Prior art date
Application number
PCT/CN2020/123946
Other languages
English (en)
French (fr)
Inventor
詹姆斯·G 迪克
周志敏
Original Assignee
江苏多维科技有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 江苏多维科技有限公司 filed Critical 江苏多维科技有限公司
Priority to EP20882910.1A priority Critical patent/EP4053551A4/en
Priority to JP2022524943A priority patent/JP2023500083A/ja
Priority to US17/755,180 priority patent/US12066401B2/en
Publication of WO2021083137A1 publication Critical patent/WO2021083137A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/12—Measuring magnetic properties of articles or specimens of solids or fluids
    • G01R33/18—Measuring magnetostrictive properties
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/12—Measuring force or stress, in general by measuring variations in the magnetic properties of materials resulting from the application of stress
    • G01L1/125—Measuring force or stress, in general by measuring variations in the magnetic properties of materials resulting from the application of stress by using magnetostrictive means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
    • G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
    • G01L1/2206—Special supports with preselected places to mount the resistance strain gauges; Mounting of supports
    • G01L1/2231—Special supports with preselected places to mount the resistance strain gauges; Mounting of supports the supports being disc- or ring-shaped, adapted for measuring a force along a single direction
    • G01L1/2237—Special supports with preselected places to mount the resistance strain gauges; Mounting of supports the supports being disc- or ring-shaped, adapted for measuring a force along a single direction the direction being perpendicular to the central axis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/0004—Gaseous mixtures, e.g. polluted air
    • G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
    • G01N33/0027—General constructional details of gas analysers, e.g. portable test equipment concerning the detector
    • G01N33/0036—General constructional details of gas analysers, e.g. portable test equipment concerning the detector specially adapted to detect a particular component
    • G01N33/005—H2
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
    • G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
    • G01R33/09—Magnetoresistive devices
    • G01R33/091—Constructional adaptation of the sensor to specific applications
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
    • G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
    • G01R33/09—Magnetoresistive devices
    • G01R33/098—Magnetoresistive devices comprising tunnel junctions, e.g. tunnel magnetoresistance sensors

Definitions

  • the disclosed embodiments relate to gas sensor technology, and in particular to a hydrogen sensor based on an electrically isolated magnetoresistive stress sensitive element.
  • Hydrogen as a renewable, non-hazardous new energy source that replaces fossil energy, has attracted more and more attention worldwide in recent years and has been developing rapidly. At present, the world's major economies, such as the United States, the European Union, and Japan, are sparing no effort to promote hydrogen as a new energy and new fuel for future vehicles and households. Companies such as Toyota have begun to design and produce hydrogen-fueled vehicles.
  • Hydrogen cannot be sensed by human senses, but it is highly flammable and explosive.
  • the flammability threshold of hydrogen in the air is about 4%.
  • a reliable and highly sensitive hydrogen sensor is required.
  • the embodiment of the disclosure provides a hydrogen sensor based on an electrically isolated magnetoresistive stress sensitive element to improve the performance of the hydrogen sensor.
  • the embodiment of the present disclosure provides a hydrogen sensor based on an electrically isolated magnetoresistive stress sensitive element, including: a deformable substrate;
  • a magnetoresistive stress sensor bridge located on the deformable substrate, an electrical isolation layer covering the magnetoresistive stress sensor bridge, and a magnetic shielding layer located on the electrical isolation layer;
  • a hydrogen sensitive layer located above the deformable substrate, the orthographic projection of the hydrogen sensitive layer on the plane where the deformable substrate is located covers the electrical isolation layer, and the hydrogen sensitive layer is used to adsorb or desorb hydrogen gas for expansion Or shrink and deform and cause the stress change of the deformable substrate, and the magnetoresistive stress sensor bridge is used to measure the hydrogen concentration according to the stress change of the deformable substrate.
  • a hydrogen sensor based on an electrically isolated tunnel magnetoresistive stress sensitive element includes a deformable substrate, a tunnel magnetoresistive stress sensor bridge on the deformable substrate, and a TMR stress sensor.
  • the magnetic shielding layer and hydrogen sensitive layer on the electric bridge, the hydrogen sensitive layer is used to absorb or desorb hydrogen gas and expand or contract, which causes the change of the stress of the deformable substrate.
  • the magnetoresistive stress sensor bridge collects the stress signal and It is converted into an electrical signal, and the hydrogen concentration can be measured according to the relationship between stress and hydrogen concentration.
  • the deformable substrate can be sensitively and real-timely changed according to the change of the hydrogen sensitive layer, which improves the sensitivity and reaction rate of the hydrogen sensor, and the measurement method is simple.
  • the setting of the electrical isolation layer can realize the hydrogen environment
  • the electrical isolation between the bridge and the magnetoresistive stress sensor ensures safety. It can also be used in environments with high hydrogen concentration to increase the measurement range. Improve the new capabilities of the hydrogen sensor.
  • FIG. 1 is a schematic diagram of a hydrogen sensor provided by an embodiment of the present disclosure
  • FIG. 2 is a schematic diagram of the structure and stress distribution of the hydrogen sensitive layer and the cantilever beam provided by the embodiment of the present disclosure
  • FIG. 3 is a schematic diagram of the structure and stress distribution of the hydrogen sensitive layer and the cantilever beam provided by the embodiment of the present disclosure
  • FIG. 4 is a diagram of the structure and stress distribution of the hydrogen sensitive layer and the diaphragm assembly provided by the embodiment of the present disclosure
  • FIG. 5 is a schematic diagram of a stacked structure of magnetoresistance sensing units in an embodiment of the disclosure
  • FIG. 6 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the cantilever beam provided by the embodiment of the present disclosure
  • FIG. 7 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the diaphragm assembly provided by the embodiment of the present disclosure
  • FIG. 8 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the diaphragm assembly provided by the embodiment of the present disclosure
  • 9A-9P are diagrams of the rotation angle of the free layer of the magnetoresistive sensing unit under tension and compression stress when the free layer of the magnetoresistive sensing unit is at different initial magnetic moments;
  • 10A-10D are the circumferential distribution diagrams of the initial magnetic moment angle and rotation angle of the free layer under tensile stress and compressive stress;
  • FIG. 11 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the cantilever beam provided by the embodiment of the present disclosure
  • FIG. 12 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the cantilever beam provided by the embodiment of the present disclosure
  • FIG. 13 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the diaphragm assembly provided by the embodiment of the present disclosure
  • FIG. 14 is a schematic diagram of the structure and stress distribution of the push-pull magnetoresistive stress sensor bridge and the diaphragm assembly provided by the embodiment of the present disclosure
  • Figures 15A-15F are the circumferential distribution diagrams of the initial magnetic moment angle and rotation angle of the free layer under tensile stress and compressive stress;
  • 16 is a schematic diagram of the structure and stress distribution of the reference magnetoresistive stress sensor bridge and the cantilever beam provided by the embodiment of the present disclosure
  • 17 is a schematic diagram of the structure and stress distribution of the reference magnetoresistive stress sensor bridge and the diaphragm assembly provided by the embodiment of the present disclosure
  • FIG. 18 is a schematic diagram of the structure and stress distribution of the reference magnetoresistive stress sensor bridge and the diaphragm assembly provided by the embodiment of the present disclosure
  • Figures 19A-19D are the circumferential distribution diagrams of the initial magnetic moment angle and rotation angle of the free layer under the action of reference tensile and compressive stress;
  • 20A-20D are schematic diagrams of the bridge structure of the magnetoresistive stress sensor bridge.
  • FIG. 1 it is a schematic diagram of a hydrogen sensor based on an electrically isolated magnetoresistive stress sensitive element according to an embodiment of the present disclosure.
  • the hydrogen sensor provided in this embodiment includes: a deformable substrate 1; a magnetoresistive stress sensor bridge 2 located on the deformable substrate 1, an electrical isolation layer 3 covering the magnetoresistive stress sensor bridge 2, and an electrical isolation layer 3 located on the electrical isolation layer 3. Magnetic shielding layer 4; the hydrogen sensitive layer 5 located above the deformable substrate 1.
  • the hydrogen sensitive layer 5 covers the electrical isolation layer 3 in the orthographic projection of the plane where the deformable substrate 1 is located.
  • the hydrogen sensitive layer 5 is used to adsorb or desorb hydrogen to generate
  • the expansion or contraction deformation causes a change in the stress of the deformable substrate 1
  • the magnetoresistive stress sensor bridge 2 is used to measure the hydrogen concentration according to the change in the stress of the deformable substrate 1.
  • the optional deformable substrate 1 is any kind of deformable film or substrate. In the original state, the deformable substrate 1 is in a planar state, and in the deformed state, the deformable substrate 1 is deformed and a stress change occurs.
  • the deformable substrate 1 is a cantilever beam; or, the deformable substrate is a diaphragm assembly, the diaphragm assembly includes a frame and a diaphragm packaged in the frame, and the magnetoresistive stress sensor bridge is arranged on the diaphragm.
  • a magnetoresistive stress sensor bridge 2 is provided on the deformable substrate 1.
  • the magnetoresistive stress sensor bridge 2 includes a magnetoresistive sensing unit, and the magnetoresistive stress sensor bridge 2 is covered with an electrical isolation layer 3 and The magnetic shielding layer 4 on the electrical isolation layer 3.
  • the electrical isolation layer 3 can realize the electrical insulation isolation between the power environment and the external environment of the magnetoresistive stress sensor bridge 2, especially in the hydrogen environment, to achieve the isolation between the hydrogen environment and the power environment, avoid hydrogen explosions, and improve product testing safety Sex.
  • the magnetic shielding layer 4 can isolate the magnetic field of the external environment from the magnetoresistive stress sensor bridge 2, avoiding the influence of the magnetic field of the external environment on the magnetoresistive stress sensor bridge 2, so that the magnetoresistive stress sensor bridge 2 mainly collects the deformation of the deformable substrate 1.
  • the deformation signal improves the test accuracy of the magnetoresistive stress sensor bridge 2.
  • the optional magnetoresistive stress sensor bridge 2 is a tunnel magnetoresistive stress sensor bridge.
  • the optional electrical isolation layer is any film layer that can achieve electrical insulation and isolation, and the optional magnetic shielding layer is any type that can achieve electromagnetic shielding. ⁇ Film layer.
  • a hydrogen sensitive layer 5 is provided on the deformable substrate 1.
  • the hydrogen sensitive layer 5 can optionally be pasted on the magnetic shielding layer 4 as shown in FIG. 1. In other embodiments, the hydrogen sensitive layer can be directly pasted. Covered on the deformable substrate.
  • the orthographic projection of the hydrogen sensitive layer 5 on the plane of the deformable substrate 1 covers the electrical isolation layer 3.
  • the deformation of the hydrogen sensitive layer 5 due to the adsorption or desorption of hydrogen can cause the deformable substrate 1 in the area covered by it to deform, and then it is located on the cover
  • the magnetoresistive stress sensor bridge 2 of the region can measure the hydrogen concentration according to the stress change of the deformable substrate 1.
  • the hydrogen sensitive layer 5 will expand and deform when it absorbs hydrogen gas, and the hydrogen sensitive layer 5 will shrink and deform when it desorbs hydrogen gas.
  • the hydrogen sensitive layer adopts a non-Pd hydrogen storage metal or alloy, which can react with hydrogen to form a hydride, which leads to an increase in the lattice constant and an increase in volume and length.
  • the optional hydrogen sensitive layer includes at least one of AB 5 , AB 3 , AB 2 , AB and A 2 B type intermetallic compounds, wherein A represents a strong metal hydride forming element, and B represents a transition metal element.
  • A represents a strong metal hydride forming element
  • B represents a transition metal element.
  • Optional A includes rare earth metals, Ca, Mg, Zr, or Ti, and B includes Ni, Co, Fe, Mn, or Cr.
  • the optional magnetoresistive stress sensor bridge 2 may be located on the upper surface of the deformable substrate 1.
  • the magnetoresistive stress sensor bridge may be located on the lower surface of the deformable substrate, or, in other embodiments, the magnetoresistive stress sensor bridge may be distributed on the upper surface and the lower surface of the deformable substrate at the same time. surface. It can be understood that regardless of whether the magnetoresistive stress sensor bridge is arranged on one side surface or both sides of the deformable substrate, the magnetoresistive stress sensor bridge is sequentially laminated with an electrical isolation layer and a magnetic shielding layer.
  • the optional magnetoresistive stress sensor bridge 2 has an electrical transmission port assembly 7 directly connected to the deformable substrate 1, and a sealant 8 seals the electrical transmission port assembly 7 on the deformable substrate 7.
  • the deformable substrate 7 includes the substrate 6,
  • the electrical transmission port assembly 7 includes the power port, ground port, and output port of the magnetoresistive stress sensor bridge 2, and the electrical transmission port assembly 7 is located above the substrate 6 and is The glue of the sealant 8 is sealed.
  • the hydrogen sensitive layer 5 In a hydrogen atmosphere, the hydrogen sensitive layer 5 will absorb hydrogen and become a metal hydride, and its volume and length will expand or elongate; in a non-hydrogen atmosphere, the hydride in the hydrogen sensitive layer 5 will release hydrogen and reduce to For metals and alloys, the volume and length of the hydrogen sensitive layer 5 are restored to their original state.
  • the hydrogen sensitive layer 5 has the characteristics of adsorbing or desorbing hydrogen similar to the thermal expansion and contraction of the material.
  • a hydrogen expansion coefficient ⁇ can be defined for the hydrogen sensitive layer 5.
  • the relationship between the hydrogen expansion coefficient ⁇ and the hydrogen sensitive layer 5 is similar to the thermal expansion coefficient and The relationship between the materials, the hydrogen expansion coefficient ⁇ characterizes the characteristics of hydrogen absorption or desorption of hydrogen in the hydrogen sensitive layer, and the expression (1) of the hydrogen expansion coefficient ⁇ is:
  • L is the original length of the hydrogen sensitive layer
  • c is the hydrogen concentration.
  • the hydrogen expansion coefficient ⁇ is a function of the hydrogen concentration c and is directly proportional to the hydrogen concentration c.
  • the optional deformable substrate 1 is a cantilever beam.
  • the cantilever beam 1 includes a fixed portion 1a and a free portion 1b provided on one side of the fixed portion 1a.
  • the extension direction of the free portion 1b is the X-axis direction, and the magnetoresistive stress sensor bridge 2 is provided in The free part 1b of the cantilever beam 1.
  • the hydrogen sensitive layer 5 and the cantilever beam 1 form a double-layer structure.
  • the double layer mentioned here means that the hydrogen sensitive layer 5 and the cantilever beam 1 directly or indirectly form a double-layer structure, and the deformation of the hydrogen sensitive layer 5 is restricted by the cantilever beam 1. .
  • the hydrogen sensitive layer 5 is located on the upper surface of the cantilever beam 1.
  • the hydrogen sensitive layer 5 absorbs hydrogen and undergoes expansion and deformation, causing the free portion 1b of the cantilever beam 1 to deform and the internal stress on the cross section 11 of the cantilever beam 1 to change .
  • the free portion 1b of the cantilever beam 1 will bend downward, and the upper surface of the cantilever beam 1 will generate tensile stress (also called tensile stress) 12, and the lower surface of the cantilever beam 1 will generate a compressive stress 13, wherein
  • the 10 plane corresponds to the zero strain plane in section 11.
  • the hydrogen sensitive layer 5 is located on the lower surface of the cantilever beam 1.
  • the hydrogen sensitive layer 5 absorbs hydrogen and undergoes expansion and deformation, which causes deformation of the free portion 1b of the cantilever beam 1 and internal stress on the section 11' of the cantilever beam 1. Variety.
  • the free portion 1b of the cantilever beam 1 will bend upward, and the upper surface of the cantilever beam 1 will generate a compressive stress 12', and the lower surface of the cantilever beam 1 will generate a tensile stress 13', where the 10' plane in the cantilever beam 1 corresponds to the section 11 'In the 0 strain plane.
  • the stress is ⁇ , the tensile stress ⁇ >0, and the compressive stress ⁇ 0.
  • the tensile stress can be characterized as the tensile stress of the hydrogen-sensitive layer on the surface of the deformable substrate or the tensile stress of the deformable substrate surface on the hydrogen-sensitive layer
  • the compressive stress can be characterized as the compressive stress of the hydrogen-sensitive layer on the surface of the deformable substrate It can also be characterized as the compressive stress of the surface of the deformable substrate to the hydrogen sensitive layer. Since the deformation of the hydrogen sensitive layer 5 is constrained by the cantilever beam 1, the stress ⁇ generated by the cantilever beam 1 in the hydrogen sensitive layer 5 can be expressed by the following formula:
  • Es is the Young's modulus of the cantilever
  • ds is the thickness of the cantilever
  • C is the bending radius of the cantilever
  • Vs is the Poisson's ratio of the cantilever
  • ⁇ f is the internal stress of the hydrogen sensitive layer
  • d f is the thickness of the hydrogen sensitive layer .
  • the stress ⁇ in the hydrogen sensitive layer 5 can also be expressed as follows according to the hydrogen expansion coefficient ⁇ :
  • E f is the Young's modulus of the hydrogen sensitive layer
  • V f is the Poisson's ratio of the hydrogen sensitive layer
  • the stress ⁇ is proportional to the hydrogen concentration c, and the magnetoresistive stress sensor bridge can obtain the hydrogen concentration by measuring the stress ⁇ .
  • the optional deformable substrate 1 is a diaphragm assembly.
  • the diaphragm assembly includes a frame 61(3) and a diaphragm 62(3) encapsulated in the frame 61(3).
  • the magnetoresistive stress sensor bridge is arranged on the diaphragm 62(3). )on.
  • the optional magnetoresistive stress sensor bridge is located on the upper surface or the lower surface of the diaphragm 62(3), and the magnetoresistive stress sensor bridge can also be located on the upper and lower surfaces of the diaphragm 62(3) at the same time.
  • the bridge includes a plurality of magnetoresistance sensing units 64(1).
  • the diaphragm 62(3) coated with multiple layers will bend. Although this kind of deformation is very small, it can be deformed by laser
  • the interferometer or the surface profiler can still measure the radius of curvature of the deflection.
  • the degree of deflection on the diaphragm 62(3) reflects the magnitude of the residual stress of the multi-layer film.
  • the multi-layer film specifically refers to the formation on the diaphragm. A collection of thin film layers.
  • the stress formula is as follows:
  • t s and t f respectively correspond to the thickness of the film layer and the diaphragm
  • r is the radius of curvature
  • E and v are the elastic modulus and Poisson's ratio of the diaphragm, respectively.
  • the stress in the hydrogen sensitive layer on the diaphragm is also proportional to the hydrogen expansion coefficient ⁇ , and its formula is expressed as follows:
  • E f is the Young's modulus of the hydrogen sensitive layer
  • V f is the Poisson's ratio of the hydrogen sensitive layer
  • the stress ⁇ is proportional to the hydrogen concentration c, and the magnetoresistive stress sensor bridge can obtain the hydrogen concentration by measuring the stress ⁇ .
  • both the cantilever beam and the diaphragm assembly are coated with a hydrogen sensitive layer on the substrate.
  • the hydrogen sensitive layer absorbs hydrogen, the volume and length of the hydrogen sensitive layer are stretched and deformed.
  • the substrate produces changes in stress and deflection, so the stress direction and magnitude of the stress on the surface of the diaphragm and the cantilever beam have a similar relationship.
  • the substrate of the cantilever beam is the main body of the beam
  • the substrate of the diaphragm assembly is the diaphragm.
  • the difference between the cantilever beam and the diaphragm assembly is that the cantilever beam has a fixed end, while the diaphragm is fixed all around.
  • a hydrogen sensor based on an electrically isolated tunnel magnetoresistive stress sensitive element includes a deformable substrate, a tunnel magnetoresistive stress sensor bridge on the deformable substrate, and a TMR stress sensor.
  • the magnetic shielding layer and hydrogen sensitive layer on the electric bridge, the hydrogen sensitive layer is used to absorb or desorb hydrogen gas and expand or contract, which causes the change of the stress of the deformable substrate.
  • the magnetoresistive stress sensor bridge collects the stress signal and It is converted into an electrical signal, and the hydrogen concentration can be measured according to the relationship between stress and hydrogen concentration.
  • the deformable substrate can be sensitively and real-timely changed according to the change of the hydrogen sensitive layer, which improves the sensitivity and reaction rate of the hydrogen sensor, and the measurement method is simple.
  • the setting of the electrical isolation layer can realize the hydrogen environment
  • the electrical isolation between the bridge and the magnetoresistive stress sensor ensures safety. It can also be used in environments with high hydrogen concentration to increase the measurement range. Improve the new capabilities of the hydrogen sensor.
  • the longitudinal direction of the deformable substrate is the X-axis direction
  • the width direction of the deformable substrate is the Y-axis direction
  • the magnetoresistive stress sensor bridge includes a plurality of
  • the magnetoresistance sensing unit includes a multi-film layer stack structure 2'parallel to the XY plane, and the multi-film layer 2'includes at least a pinning layer 2e, a reference layer 2d, a barrier layer 2c, Free layer 2b and bias layer 2a.
  • a side view of the cantilever beam and a front view of the fixed part are shown, wherein the X axis direction is parallel to the length direction of the cantilever beam, the Y axis direction is parallel to the width direction of the cantilever beam, that is, the width direction of the fixed part, XY
  • the plane is the plane formed by the X-axis direction and the Y-axis direction.
  • the deformable substrate is a cantilever beam
  • the longitudinal direction of the elongated shape is the longitudinal direction of the deformable substrate, that is, the X-axis direction.
  • the short side direction of the elongated shape is the width direction of the deformable substrate, that is, the Y-axis direction.
  • the deformable substrate is a diaphragm assembly, where the diaphragm is a square, and the adjacent two sides of the square are the length direction of the deformable substrate, that is, the X-axis direction.
  • the width direction is the Y-axis direction.
  • the magnetoresistive stress sensor bridge is arranged on the surface of the deformable substrate, and the arrangement direction of the magnetoresistive sensing units in the magnetoresistive stress sensor bridge is the length direction of the deformable substrate, that is, the X-axis direction.
  • the magnetoresistive stress sensor bridge The extension direction of the medium magnetoresistance sensor unit is the width direction of the deformable substrate, that is, the Y-axis direction.
  • FIG. 5 shows the film layer stack structure of the magnetoresistive stress sensor bridge.
  • the magnetization direction of the reference layer 2d is determined by the pinned layer 2e, and the bias direction of the free layer 2b is determined by the bias layer 2a.
  • the principle of the tunnel magnetoresistive TMR stress sensor is to use the magnetostrictive effect of the free layer 2b to rotate the magnetic moment of the free layer 2b under the action of stress, thereby making the angle between the free layer 2b and the reference layer 2e
  • ⁇ changes the relationship between the resistance of the magnetoresistance sensing unit and the angle ⁇ between the free layer 2b and the reference layer 2e is:
  • ⁇ s is the magnetostriction coefficient
  • Ms is the saturation magnetization
  • the optional deformable substrate has a first surface and a second surface arranged along the Z-axis direction;
  • the magnetoresistive stress sensor bridge is a push-pull bridge structure, and the magnetoresistive stress
  • the sensor bridge includes a push magnetic resistance sensing unit and a pull magnetic resistance sensing unit; the push magnetic resistance sensing unit is arranged on the first surface, the pull magnetic resistance sensing unit is arranged on the second surface, and the push magnetic resistance sensing unit And the pull magnet resistance sensor unit bears the same magnitude and opposite direction stress.
  • the optional deformable substrate is a cantilever beam or a diaphragm assembly.
  • the first surface and the second surface described herein are both parallel to the XY plane, and the Z axis direction is perpendicular to the XY plane.
  • the push magnetoresistive sensor unit and the pull magnet The resistance sensing unit is located on two opposite surfaces of the deformable substrate.
  • the push magnetic resistance sensing unit is located on the upper surface of the deformable substrate and the pull magnetic resistance sensing unit is located on the lower surface of the deformable substrate, or the push magnetic resistance
  • the sensing unit is located on the lower surface of the deformable substrate and the pull-magnetic resistance sensing unit is located on the upper surface of the deformable substrate.
  • Figure 6 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the cantilever beam.
  • the hydrogen sensitive layer 5 is located on the upper surface of the cantilever beam 1
  • the push magnetic resistance sensing unit 20 and the pull magnetic resistance sensing unit 21 are respectively located above and below the cantilever beam 1
  • the corresponding electrical isolation layer 3 (1) covers the push magnetic resistance
  • the electrical isolation layer 3(2) covers the surface of the pull magnetic resistance sensing unit 21
  • the magnetic shielding layers 4(1) and 4(2) are located on the push magnetic resistance sensing unit 20 and the pull magnetic resistance respectively.
  • the zero-stress plane 10 is located at the middle position ds/2 of the cantilever beam 1, and the magnetoresistance sensor unit 20 and the pull magnetoresistance sensor unit 21 are pushed.
  • the magnitude of the stress is the same, but the direction is opposite.
  • Optional push magnetoresistance sensing unit 20 is subjected to tensile stress 12 and tensile stress ⁇ 1>0
  • pull magnetoresistance sensing unit 21 is subjected to compressive stress 13 and compressive stress ⁇ 2 ⁇ 0
  • the hydrogen sensitive layer may be located on the lower surface of the cantilever beam, or the hydrogen sensitive layer may cover the upper part of the pull magnetoresistive sensing unit.
  • Figure 7 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the diaphragm.
  • the diaphragm assembly includes a peripheral frame (not labeled) and a diaphragm 1 (21) defined by the peripheral frame.
  • the hydrogen sensor also includes a push magnetic resistance sensing unit 20 (21) located on the diaphragm 1 (21) and an electrical isolation layer 3 (21), and a pull magnetic resistance sensing unit 21 (21) located below the diaphragm 1 (21) ) And an electrical isolation layer 31 (21), as well as a magnetic shielding layer 4 (21) located above the push magnetic resistance sensing unit 20 (21) and a magnetic shielding layer 41 ( 21), and the hydrogen sensitive layer 5(21) on the magnetic shielding layer 4(21).
  • the hydrogen sensitive layer 5(21) expands or elongates after absorbing hydrogen, and the diaphragm will bend upward.
  • Figure 8 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the diaphragm.
  • the diaphragm assembly includes a peripheral frame (not labeled) and a diaphragm 1 (23) defined by the peripheral frame.
  • the hydrogen sensor also includes a push magnetic resistance sensing unit 20 (23) located on the diaphragm 1 (23) and an electrical isolation layer 3 (23), and a pull magnetic resistance sensing unit 21 (23) located below the diaphragm 1 (23) ) And an electrical isolation layer 31 (23), as well as a magnetic shielding layer 4 (23) located above the push magnetic resistance sensing unit 20 (23) and a magnetic shielding layer 41 ( 23), and the hydrogen sensitive layer 5 (23) on the magnetic shielding layer 41 (23).
  • the hydrogen sensitive layer 5 (23) expands or stretches after absorbing hydrogen, and the diaphragm will bend downward.
  • the angle of the starting magnetic moment of the free layer of the optional push magnetoresistance sensor unit deviating from the Y axis is ⁇ ; the free layer magnetic moment of the push magnetoresistance sensor unit and the free layer magnetic moment of the pull magnetoresistance sensor unit rotate clockwise at the same time Or rotate the same angle counterclockwise at the same time to obtain the corresponding pinned layer magnetic moment, the angle of the starting magnetic moment of the free layer of the pull magnetoresistive sensor unit from the Y axis is 90- ⁇ or 270- ⁇ ; or, push magnetoresistive sensing
  • the rotation direction of the free layer magnetic moment of the unit and the free layer magnetic moment of the pull magnetoresistive sensor unit are different and the rotation angle is the same.
  • the angle of the free layer initial magnetic moment of the pull magnetoresistive sensor unit from the Y axis is 90+ ⁇ or 270+ ⁇ ; ⁇ is in the range of 0° to 360°, where the free layer adopts materials with positive magnetostriction coefficient and bears tensile stress, or adopts materials with negative magnetostriction coefficient and bears compressive stress.
  • the free layer uses a material with a positive magnetostriction coefficient and bears compressive stress, or uses a material with a negative magnetostriction coefficient and when it bears a tensile stress, ⁇ is not 90° or 270°. It should be noted that the signs and values of angles in the embodiments of the present disclosure are all degrees degrees.
  • Figures 9A to 9P are diagrams of the free layer magnetic moment rotation angles under tension and compression stress when the free layer of the magnetoresistive sensing unit is at different initial magnetic moment angles.
  • the initial magnetic moment angle of the free layer specifically refers to the angle at which the initial magnetic moment of the free layer deviates from the Y axis (specifically, the +Y axis). After being stressed, the magnetic moment of the free layer rotates.
  • the longitudinal direction of the deformable substrate is defined as the X-axis direction
  • the width direction of the deformable substrate is defined as the Y-axis direction
  • the axial direction of the stress ⁇ is the X-axis direction.
  • Fig. 9A the initial magnetic moment of the free layer deviates from the Y axis by an angle ⁇ .
  • the rotation angle of the magnetic moment of the free layer is ⁇ .
  • Fig. 9B the initial magnetic moment of the free layer deviates from the Y axis by an angle ⁇ .
  • the compressive stress ⁇ 0 the rotation angle of the magnetic moment of the free layer is ⁇ 1.
  • Fig. 9C the initial magnetic moment of the free layer deviates from the Y axis by an angle of 90- ⁇ .
  • the rotation angle of the magnetic moment of the free layer is ⁇ 1.
  • the initial magnetic moment of the free layer deviates from the Y axis by an angle of 360- ⁇ .
  • the rotation angle of the magnetic moment of the free layer is ⁇ 1.
  • the tensile stress ⁇ >0 is equivalent to the equivalent magnetic field H ⁇ along the X axis in the coordinate system
  • the compressive stress ⁇ 0 is equivalent to the equivalent magnetic field H ⁇ along the Y direction.
  • the free layer magnetic moment Mf can be rotated 90° counterclockwise to obtain the pinned layer magnetic moment Mr.
  • the pinned layer magnetic moment is defined as CCW (Counterclockwise); on the contrary, the free layer magnetic moment Mf is rotated 90° clockwise to get the pinned layer magnetic moment Mr, and the free layer magnetic moment is rotated clockwise to get the pinning
  • the layer magnetic moment is defined as CW (clockwise).
  • Table 1 lists the free layer rotational magnetic moment of the free layer magnetic moment under tensile stress and compressive stress when the free layer magnetic moment is at different initial deflection angles, where + represents an increase in the angle between the free layer and the pinned layer,- It means that the angle between the free layer and the pinned layer is reduced. It can be seen from Table 1 that the initial deflection angle of the same free layer, under the conditions of tensile stress ( ⁇ >0) and compressive stress ( ⁇ 0), the amplitude of the free layer rotation angle is different, respectively ⁇ 1 and ⁇ , or ⁇ and ⁇ 1, in addition, its direction is also different, respectively + and -, or-and +. Table 1 is as follows:
  • Figures 10A-10D are the circumferential distribution diagrams of the initial magnetic moment angle and rotation angle of the free layer under tensile and compressive stresses, where ⁇ is represented by a solid circle, + ⁇ is represented by + in the solid circle, and - ⁇ is represented by It is-in the solid circle; ⁇ 1 is represented as a hollow circle, + ⁇ 1 is represented as + in the hollow circle, and - ⁇ 1 is represented as-in the hollow circle.
  • xxx no means that the angular position is invalid, the inner ring represents tensile stress ( ⁇ >0), the outer ring represents compressive stress ( ⁇ 0), and the arrow represents the initial magnetic moment angular orientation of the free layer magnetic moment Mf on the cantilever beam.
  • Fig. 10D is the inner ring TMR/ represented in Figs. 9A-9P
  • Outer ring TMR CW ⁇ >0/CCW ⁇ 0.
  • the free layer rotation angle of the push magnetoresistive sensor unit is + ⁇ when the tensile stress ⁇ >0, and the free layer rotation angle of the pull magnetoresistance sensor unit is - ⁇ when the compressive stress ⁇ 0; or, push magnetoresistance transmission
  • the free layer rotation angle of the sensing unit is + ⁇ 1 when the tensile stress ⁇ >0, and the free layer rotation angle of the pull magnetoresistance sensing unit is - ⁇ 1 when the compressive stress ⁇ 0.
  • the push-pull bridge structure shown in Figure 6 corresponds to the CCW/CCW and CW/CW structures, that is, the free layer magnetic moment of the push magnetoresistance sensor unit and the free layer magnetic moment of the pull magnetoresistance sensor unit rotate clockwise or at the same time Rotate the same angle counterclockwise to obtain the corresponding pinned layer magnetic moment, and the corresponding initial magnetic moment angle relationship of the push arm and the pull arm is shown below.
  • the free layer rotation angle of the push magnetoresistive sensor unit is + ⁇ when the tensile stress ⁇ >0, then look at its inner ring.
  • the angles corresponding to + ⁇ include ⁇ and 180+ ⁇ ; at this time, it is required to pull
  • the rotation angle of the free layer of the magnetoresistance sensor unit should be - ⁇ when the compressive stress ⁇ 0, then look at its outer ring, the angles corresponding to - ⁇ include 90- ⁇ and 270- ⁇ .
  • the free layer rotation angle of the push magnetoresistive sensor unit is + ⁇ when the tensile stress ⁇ >0, then look at its inner ring, the angles corresponding to + ⁇ include 360- ⁇ and 180- ⁇ ; at this time, It is required that the free layer rotation angle of the pull magnet resistance sensing unit should be - ⁇ when the compressive stress ⁇ 0, then look at the outer ring, the angles corresponding to - ⁇ include 90+ ⁇ and 270+ ⁇ .
  • the free layer rotation angle of the push magnetoresistance sensor unit is + ⁇ 1 when the tensile stress ⁇ >0, then look at its inner ring, the angles corresponding to + ⁇ 1 include 90- ⁇ and 270- ⁇ ; It is required that the free layer rotation angle of the pull magnetoresistive sensor unit should be - ⁇ 1 when the compressive stress ⁇ 0, then look at the outer ring.
  • the angles corresponding to - ⁇ 1 include ⁇ and 180+ ⁇ .
  • the free layer rotation angle of the push magnetoresistive sensor unit is + ⁇ 1 when the tensile stress ⁇ >0, then look at its inner ring, the angles corresponding to + ⁇ 1 include 90+ ⁇ and 270+ ⁇ ; It is required that the free layer rotation angle of the pull magnetoresistive sensor unit should be - ⁇ 1 when the compressive stress ⁇ 0, then look at the outer ring.
  • the angles corresponding to - ⁇ 1 include 360- ⁇ and 180- ⁇ .
  • the push-pull bridge structure shown in Figure 6 corresponds to the CCW/CW and CW/CCW structures, that is, the direction of rotation of the free layer magnetic moment of the push magnetoresistive sensor unit and the free layer magnetic moment of the pull magnetoresistance sensor unit Different but rotating the same angle to obtain the corresponding pinned layer magnetic moment, the corresponding initial magnetic moment angle relationship of the push arm and the pull arm refer to FIG. 10C and FIG. 10D, and the content of Table 3 is obtained.
  • the optional deformable substrate has a first surface and a second surface arranged along the Z-axis direction;
  • the magnetoresistive stress sensor bridge is a push-pull bridge structure, and the magnetoresistive stress
  • the sensor bridge includes a push magnetic resistance sensing unit and a pull magnetic resistance sensing unit; the push magnetic resistance sensing unit and the pull magnetic resistance sensing unit are arranged on the first surface or the second surface at the same time, and the push magnetic resistance
  • the sensing unit and the pull magnet resistance sensing unit bear the same magnitude and the same direction of stress.
  • the optional deformable substrate is a cantilever beam or a diaphragm assembly.
  • the first surface and the second surface described herein are both XY planes, and the Z axis direction is perpendicular to the XY plane.
  • the push magnetic resistance sensing unit and the pull magnetic resistance The sensing units are located on the same surface of the deformable substrate.
  • the push magnetoresistance sensing unit and the pull magnetoresistance sensing unit are both located on the lower surface of the deformable substrate, or at the same time on the upper surface of the deformable substrate.
  • Figure 11 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the cantilever beam.
  • the push magnetic resistance sensing unit 20 (11) and the pull magnetic resistance sensing unit 20 (12) are both located on the upper surface of the cantilever beam 1 (11), and are isolated by covering the surface with an electrical isolation layer 3 (11)
  • the magnetic shielding layer 4 (11) is located above the push magnetic resistance sensing unit 20 (11) and the pull magnetic resistance sensing unit 20 (12) for shielding the influence of the external magnetic field
  • the hydrogen sensitive layer 5 (11) is located at the top for direct It reacts with hydrogen
  • 10 (11) is the zero strain plane of the cantilever beam 1 (11).
  • the deformation of the hydrogen sensitive layer 5 (11) will cause the cantilever beam 1 (11) to bend downwards, and pull the cantilever beam 1 (11) in both the push magnetic resistance sensing unit 20 (11) and the pull magnetic resistance sensing unit 20 (12). Stress 12(11) ⁇ >0.
  • Figure 12 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the cantilever beam.
  • the push magnetic resistance sensing unit 21 (12) and the pull magnetic resistance sensing unit 210 (12) are both located on the lower surface of the cantilever beam 1 (12), and are isolated by covering the surface with an electrical isolation layer 3 (12)
  • the magnetic shielding layer 4 (12) is located under the push-pull magnetoresistance sensing units 21 (12) and 210 (12) for shielding the influence of external magnetic fields
  • the hydrogen sensitive layer 5 (12) is located on the upper surface of the cantilever beam 1 (12) for direct It reacts with hydrogen
  • 10 (11) is the 0 strain plane of the cantilever beam.
  • the cantilever beam will bend downward and will generate a compressive stress 13(12) ⁇ 0 in both the push magnetoresistance sensing unit 20 (11) and the pull magnetoresistance sensing unit 20 (12).
  • Figure 13 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the diaphragm. Among them, it includes diaphragm 1 (20), push magnetic resistance sensing unit 20 (20) and pull magnetic resistance sensing unit 21 (20) located on diaphragm 1 (20), and electrical isolation layer 3 (20), The magnetic shielding layer 4 (20) located above the push magnetic resistance sensing unit 20 (20) and the pull magnetic resistance sensing unit 21 (20), and the hydrogen sensitive layer 5 (20) located on the uppermost layer. At this time, the hydrogen sensitive layer 5(20) The volume expands or stretches after absorbing hydrogen, and the diaphragm will bend upward at this time.
  • Figure 14 is a push-pull magnetoresistive stress sensor bridge and its structure and stress distribution on the diaphragm. Among them, it includes diaphragm 1 (22), push magnetic resistance sensing unit 20 (22) and pull magnetic resistance sensing unit 21 (22) located on diaphragm 1 (22), and electrical isolation layer 3 (22), The magnetic shielding layer 4 (22) located above the push magnetic resistance sensing unit 20 (22) and the pull magnetic resistance sensing unit 21 (22), and the hydrogen sensitive layer 5 (22) located at the lowermost layer. At this time, the hydrogen sensitive layer 5(22) Volume expansion or extension occurs after absorbing hydrogen, and the diaphragm will bend downward.
  • the angle at which the initial magnetic moment of the free layer of the push magnetoresistance sensing unit deviates from the Y axis is ⁇ ; the free layer magnetic moment of the push magnetoresistance sensing unit and the free layer magnetic moment of the pull magnetoresistance sensing unit are simultaneously aligned Rotate 90° clockwise or 90° counterclockwise at the same time to obtain the corresponding pinned layer magnetic moment, the angle of the free layer initial magnetic moment of the pull magnetoresistive sensor unit from the Y axis is 180- ⁇ or 360- ⁇ ; or,
  • the rotation direction of the free layer magnetic moment of the push magnetoresistance sensor unit and the free layer magnetic moment of the pull magnetoresistance sensor unit are different and the rotation angle is the same.
  • the angle at which the initial magnetic moment of the free layer of the pull magnetoresistance sensor unit deviates from the Y axis Is ⁇ or 180+ ⁇ ; ⁇ is in the range of 0° to 360°, where the free layer adopts materials with positive magnetostriction coefficient and bears tensile stress or adopts materials with negative magnetostriction coefficient and bears compressive stress
  • ⁇ is not 0° or 180°
  • the free layer adopts a material with a positive magnetostriction coefficient and bears compressive stress, or uses a material with a negative magnetostriction coefficient and when it bears a tensile stress, ⁇ is not 90° or 270°.
  • FIGS. 15A-15F for the circumferential distribution diagrams of the initial magnetic moment angle and rotation angle of the free layer of the hydrogen sensor shown in FIGS. 11-14 under tensile stress or compressive stress.
  • Figure 15A is the CCW ⁇ >0/CCW ⁇ >0 configuration
  • Figure 15B is the CW ⁇ >0/CW ⁇ >0 configuration
  • Figure 15C is the CCW ⁇ 0/CCW ⁇ 0 configuration
  • Figure 15D is the CW ⁇ 0/CW ⁇ 0 group state.
  • the free layer magnetic moment of the push magnetoresistance sensor unit and the free layer magnetic moment of the pull magnetoresistance sensor unit rotate 90° clockwise or 90° counterclockwise at the same time to obtain the corresponding pinned layer magnetic moment.
  • Figure 15E shows the CW ⁇ >0/CCW ⁇ >0 configuration
  • Figure 15F shows the CCW ⁇ 0/CW ⁇ 0 configuration.
  • the free layer magnetic moment of the push magnetoresistance sensor unit and the free layer magnetic moment of the pull magnetoresistance sensor unit have different rotation directions and the same rotation angle.
  • the analysis method of the circumferential distribution process is similar to that of FIG. 9A to FIG. 9P, and will not be repeated here.
  • Table 4 shows the four configurations of push-pull magnetoresistive stress sensor bridges corresponding to CCW ⁇ >0/CCW ⁇ >0, CW ⁇ >0/CW ⁇ >0, CCW ⁇ 0/CCW ⁇ 0, CW ⁇ 0/CW ⁇ 0 Corresponding to the initial magnetic moment angle relationship table of the push arm and the pull arm, when the free layer rotation angle is + ⁇ and - ⁇ , or + ⁇ 1 and - ⁇ 1, for any push arm initial magnetic moment angle ⁇ , there is The arm's initial magnetic moment angles of 180- ⁇ and 360- ⁇ correspond to them. Table 4 is as follows:
  • Table 5 shows the relationship between the initial magnetic moment angle of the push arm and the pull arm corresponding to the push-pull magnetoresistive sensor bridge structure two corresponding to CW ⁇ >0/CCW ⁇ >0 and CCW ⁇ 0/CW ⁇ 0 ,
  • the free layer rotation angle is + ⁇ and - ⁇ , or + ⁇ 1 and - ⁇ 1
  • for any push magnetoresistive sensor unit initial magnetic moment angle ⁇ there is a pull magnetoresistance sensor unit initial magnetic moment angle ⁇ and 180+ ⁇ correspond to it.
  • Table 5 is as follows:
  • the initial magnetic moment angle ⁇ of the free layer of the push magnetoresistive sensor unit can be any angle in the range of 0-360°, while the free layer of the pull magnetoresistive sensor unit If the initial magnetic moment angle exceeds 360°, the value can be returned to the range of 0-360° by subtracting the period of 360°.
  • tensile stress ⁇ >0, ⁇ 90° and 270° for Compressive stress ⁇ 0, ⁇ 0° and 180°.
  • the optional hydrogen sensor further includes: a non-hydrogen sensitive layer on the same layer as the hydrogen sensitive layer;
  • the deformable substrate includes a cantilever beam or a diaphragm assembly;
  • the cantilever beam includes a fixed part and The reference cantilever beam and the sensitive cantilever beam on both sides of the fixed part, the reference cantilever beam is provided with a reference area, and the sensitive cantilever beam is provided with a sensitive area;
  • the diaphragm assembly includes a reference diaphragm and a sensitive diaphragm encapsulated in a frame, The reference diaphragm is provided with a reference area, and the sensitive diaphragm is provided with a sensitive area;
  • the hydrogen sensitive layer is provided on the magnetic shielding layer in the sensitive area, and the non-hydrogen sensitive layer is provided on the magnetic shielding layer in the reference area.
  • the magnetoresistive stress sensor bridge is arranged on the same side surface of the deformable substrate, for example, on the upper
  • the reference area and the sensitive area of the optional deformable substrate are located on the same plane;
  • the magnetoresistive stress sensor bridge is a reference bridge structure, and the magnetoresistive stress sensor bridge includes a reference magnetoresistance sensor unit and a sensitive magnetoresistance sensor unit;
  • the resistance sensing unit is arranged in the reference area, and the sensitive magnetoresistance sensing unit is arranged in the sensitive area.
  • the reference magnetoresistance sensor unit and the sensitive magnetoresistance sensor unit are arranged on the same side surface of the deformable substrate, for example, both are arranged on the upper surface or both are arranged on the lower surface.
  • Figure 16 shows the reference bridge type magnetoresistive stress sensor bridge and its structure and stress distribution on the cantilever beam.
  • the deformable substrate includes two cantilever beams, namely the sensitive cantilever beam 1 (14) and the reference cantilever beam 1 (15).
  • the sensitive magnetoresistance sensing unit 30 (14) is located on the surface of the reference cantilever beam 1 (14), and the reference magnetoresistance
  • the sensing unit 30 (15) is located on the surface of the reference cantilever beam 1 (15), and the electrical isolation layers 3 (14) and 3 (15) are respectively located on the sensitive magnetoresistance sensor unit 30 (14) and the reference magnetoresistance sensor unit 30 ( 15)
  • the hydrogen sensitive layer 5 (14) and the non-hydrogen sensitive layer 5'(15) are respectively located on the top layer of the sensitive cantilever beam 1 (14) and the reference cantilever beam 1 (15).
  • the hydrogen sensitive layer 5 (14) encounters hydrogen and will undergo a dimensional change, resulting in stress ⁇ 1, while the non-hydrogen sensitive layer 5'(15) will not change. Therefore, the two constitute the reference bridge magnetoresistive stress sensor bridge Sensitive bridge arm and reference bridge arm.
  • Figure 17 is a reference bridge magnetoresistive stress sensor bridge and its structure and stress distribution on the diaphragm assembly.
  • the deformable substrate includes: a sensitive diaphragm 62(1) and a reference diaphragm 62(2).
  • the sensitive diaphragm 62(1) is surrounded by the substrate frame 61(1)
  • the reference diaphragm 62(2) is surrounded by the substrate frame 61(1).
  • the sensitive magnetoresistance sensor unit 63(1) is located on the sensitive diaphragm 62(1)
  • the reference magnetoresistance sensor unit 63(2) is located on the reference diaphragm 62(2).
  • the resistance sensing unit 63(1) and the reference magnetoresistance sensing unit 63(2) are electrically connected to form a reference bridge tunnel magnetoresistive stress sensor bridge.
  • Figure 18 is a side view of the reference bridge type magnetoresistive stress sensor bridge and its structure on the diaphragm assembly. Among them, including reference diaphragm 1 (17), sensitive diaphragm 1 (16), and reference magnetoresistance sensing unit 20 (16) located on reference diaphragm 1 (17), and sensitive diaphragm 1 (16) The sensitive magnetoresistance sensing unit 20 (17), and the electrical isolation layer 3 (16) are covered between the reference magnetoresistance sensor units 20 (16), and the electrical isolation layer 3 (17) is covering the sensitive magnetoresistance sensor unit 20 (16).
  • the hydrogen sensitive layer 5 (16) absorbs hydrogen and expands, but is constrained by the sensitive diaphragm 1 (16), so that the diaphragm is bent. At this time, the sensitive magnetoresistance sensing unit 20 ( 16) Feel the compressive stress. When the hydrogen sensitive layer is above the diaphragm, the diaphragm bends downwards, and the sensitive magnetoresistance sensing unit 20 (17) feels the tensile stress. When the hydrogen sensitive layer is below the diaphragm, the diaphragm Bending upward, the non-hydrogen sensitive layer 5 (17) is not affected by hydrogen, does not bend, and feels the intrinsic stress.
  • the angle at which the initial magnetic moment of the free layer of the reference magnetoresistance sensing unit deviates from the Y axis is ⁇ , and the angle at which the initial magnetic moment of the free layer of the sensitive magnetoresistance sensing unit deviates from the Y axis is ⁇ ;
  • the free layer magnetic moment of the sensing unit and the free layer magnetic moment of the sensitive magnetoresistance sensing unit rotate clockwise or counterclockwise at the same time to obtain the corresponding pinned layer magnetic moment;
  • the value of ⁇ is in the range of 0° to 360°
  • the free layer adopts a material with a positive magnetostriction coefficient and bears tensile stress or adopts a material with a negative magnetostriction coefficient and when it bears a compressive stress, ⁇ is not 0° or 180°, and the free layer adopts a positive magnetostriction
  • a material with a high coefficient is subjected to compressive stress, or a material with a negative coefficient of elasticity is used
  • Figures 19A-19D are the circumferential distribution diagrams of the initial magnetic moment angle and rotation angle of the free layer under the action of reference tensile stress or reference compressive stress. Since the tunnel magnetoresistive sensing unit may also bring additional stress, the reference magnetic The residual stress in the layer of the resistance sensing unit 30 (15) is approximately 0, that is, ⁇ 0.
  • the reference magnetoresistance sensor unit 30 (15) should be selected to have exactly the same position and magnetic moment orientation relationship as the sensitive magnetoresistance sensor unit 30 (14), so as to eliminate the influence of residual stress as much as possible. Based on this, the angle orientation of the initial magnetic moment of the free layer of the sensitive magnetoresistance sensor unit/reference magnetoresistance sensor unit is as follows:
  • Figure 19A shows CCW ⁇ >0/CCW ⁇ 0
  • Figure 19B shows CCW ⁇ 0/CCW ⁇ 0
  • Figure 19C shows CW ⁇ >0/CW ⁇ 0
  • Figure 19D shows CW ⁇ 0/CW ⁇ 0
  • the sensitive magnetoresistance sensor The orientation of the free layer of the unit and the reference magnetoresistance sensing unit can be: in the case of tensile stress ⁇ >0, the initial magnetic moment angle of the free layer is ⁇ 0° and 180°, and in the case of compressive stress ⁇ 0, The initial magnetic moment angle of the free layer is ⁇ 90° and 270°.
  • FIG. 20A-20B For the push-pull magnetoresistive stress sensor bridge described in the above embodiment, its structure is shown in FIG. 20A-20B, wherein FIG. 20A is a push-pull half-bridge structure magnetoresistive stress sensor bridge, and FIG. 20B is a push-pull type magnetoresistive stress sensor bridge.
  • FIG. 20A is a push-pull half-bridge structure magnetoresistive stress sensor bridge
  • FIG. 20B is a push-pull type magnetoresistive stress sensor bridge.
  • Type full-bridge structure magnetoresistive stress sensor bridge The push magnetoresistance sensor unit 20 and the pull magnetoresistance sensor unit 21 respectively constitute the push arm and the pull arm of the magnetoresistive stress sensor bridge.
  • Fig. 20C-20D For the reference magnetoresistive stress sensor bridge described in the above embodiment, its structure is shown in Fig. 20C-20D, wherein Fig. 20C is a reference half-bridge structure magnetoresistive stress sensor bridge, and Fig. 20D is a reference full bridge Structural magnetoresistive stress sensor bridge.
  • the sensitive magnetoresistance sensor unit 30 (14) and the reference magnetoresistance sensor unit 30 (15) respectively constitute the sensitive arm and the reference arm of the magnetoresistive stress sensor bridge.
  • the optional magnetic shielding layer is a soft magnetic shielding layer, and its constituent materials include soft magnetic alloy materials of Co, Fe, and Ni.
  • the optional electrical isolation layer is photoresist, Al 2 O 3 , SiN, SiO 2 or SiC.
  • Optional hydrogen sensitive layers are AB 5 , AB 3 , AB 2 , AB and A 2 B type intermetallic compounds, where A represents a strong metal hydride forming element, such as rare earth metals, Ca, Mg, Zr or Ti, and B represents transition Metals Ni, Co, Fe, Mn and Cr.
  • AB 5 alloy includes LaNi 5 , RNi 5 , R is rare earth metal; MmNi 5 , Mm is rare earth mixture, including 48-50% Ce, 32-34% La, 13-14% Nd, 4-5% Pr, 1.5% Other rare earth elements; La-rich Mm is called Lm or M1.
  • Typical Lm includes 48% La, 25% Ce, 6% Pr, 21% Nd and 0.3% other rare earth elements; CaNi5; replacement type AB 5 multi-element alloy, AB A and B in 5 are partially replaced by other metals, rare earth metals in A replace each other, such as CeNi 5 , PrNi 5 , NdNi 5 replace LaNi 5 , and rare earth metals and Ca replace each other, such as Mm 1-x Ca x Ni 5 , Mm It can be partially replaced by Ti, Zr, B, Cu, and Ni atoms in ANi 5 are partially replaced by other elements, such as Co, Mn, Al, Cr, Fe, Cu, Tin, Si, B, etc.
  • binary AB 2 alloys such as Zr-based AB 2 laves alloy ZrM2
  • the free layer of the above TMR stress sensitive element has a positive magnetostriction coefficient ⁇ s>0, including: CoFeB, CoFe, NiFe high magnetostrictive materials.
  • the free layer can also have a negative magnetostriction coefficient ⁇ s ⁇ 0, the difference is only that ⁇ s ⁇ 0, ⁇ >0 is equivalent to ⁇ s>0, ⁇ 0; ⁇ s ⁇ 0, ⁇ 0 is equivalent to ⁇ s> 0, ⁇ >0.
  • the initial phase relationship between the magnetoresistive sensing units has no effect. The difference is that when ⁇ s>0, the initial angle of the magnetoresistive sensing unit with tensile stress ⁇ >0 is not 0 or 180°, and it bears compressive stress ⁇ The starting angle of the magnetoresistive sensing unit ⁇ 0 is not 90 or 270°.

Landscapes

  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biochemistry (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • General Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Medicinal Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Food Science & Technology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Measuring Magnetic Variables (AREA)
  • Hall/Mr Elements (AREA)
  • Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

一种基于电隔离磁阻应力敏感元件的氢气传感器，包括：可变形基板（1）；位于可变形基板（1）上的磁阻应力传感器电桥（2）、覆盖磁阻应力传感器电桥（2）的电隔离层（3）以及位于电隔离层（3）上的磁屏蔽层（4）；位于可变形基板（1）上方的氢敏感层（5），氢敏感层（5）在可变形基板（1）所在平面的正投影覆盖电隔离层（3），氢敏感层（5）用于吸附或脱附氢气以发生膨胀或收缩形变并引起可变形基板（1）的应力变化，磁阻应力传感器电桥（2）用于根据可变形基板（1）的应力变化进行氢气浓度测量。提高了氢气传感器的各项性能。

Description

一种基于电隔离磁阻应力敏感元件的氢气传感器 技术领域
本揭露实施例涉及气体传感器技术，尤其涉及一种基于电隔离磁阻应力敏感元件的氢气传感器。
背景技术
氢气作为替代化石能源的一种可再生、无有害排放的新能源，近年来在全球范围内吸引了越来越多的目光，并得到了快速发展。目前，世界主要经济体，如美国、欧盟、日本等都在不遗余力地推进氢气作为未来车辆与家用的新能源与新燃料，丰田等公司已经开始设计生产氢燃料汽车。
氢气不能被人体感官所感知，但其本身却是高度可燃和易爆的，氢气在空气中的可燃性阈值在4％左右。为了保证使用氢气作为能源的设备的安全，需要可靠的、高灵敏度的氢气传感器。
传统的氢气传感器种类繁多，但是多存在光学测量方法复杂，所能测量的氢气浓度范围较小，灵敏度低，反应时间长等缺陷。此外，现有传感器在实际工作时，敏感单元中需要通过电流并有电压，如果空气中氢气的浓度到达爆炸极限，有可能点燃气体并引起爆炸。
发明内容
本揭露实施例提供一种基于电隔离磁阻应力敏感元件的氢气传感器，以提高氢气传感器的性能。
本揭露实施例提供了一种基于电隔离磁阻应力敏感元件的氢气传感器，包括：可变形基板；
位于所述可变形基板上的磁阻应力传感器电桥、覆盖所述磁阻应力传感器电桥的电隔离层以及位于所述电隔离层上的磁屏蔽层；
位于所述可变形基板上方的氢敏感层，所述氢敏感层在所述可变形基板所在平面的正投影覆盖所述电隔离层，所述氢敏感层用于吸附或脱附氢气以发生膨胀或收缩形变并引起所述可变形基板的应力变化，所述磁阻应力传感器电桥用于根据所述可变形基板的应力变化进行氢气浓度测量。
本揭露实施例中，提出一种基于电隔离的隧道磁阻应力敏感元件的氢气传感器，该氢气传感器包括可变形基板、位于可变形基板上的隧道磁阻应力传感器电桥、位于该TMR应力传感器电桥上的磁屏蔽层以及氢敏感层，氢敏感层用于吸附或脱附氢气而发生膨胀或收缩，从而引起可变形基板的应力的变化，磁阻应力传感器电桥采集到应力信号并将其转变成电信号，根据应力与氢气浓度的关系，实现对氢气浓度的测量。本实施例中，可变形基板可灵敏且实时的根据氢敏感层的变化而产生相应变化，提高了氢气传感器灵敏性和反应速率，并且测量方法简单，此外，电隔离层的设置可以实现氢气环境和磁阻应力传感器电桥之间的电隔离，从而保证了安全性，还能够应用在氢气浓度较大的环境中，提高测量范围。提高了氢气传感器的各项新能。
附图说明
为了更清楚地说明本揭露实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图做一简单地介绍，显而易见地，下面描述中的附图是本揭露的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1是本揭露实施例提供的氢气传感器的示意图；
图2是本揭露实施例提供的氢敏感层和悬臂梁的结构及应力分布示意图；
图3是本揭露实施例提供的氢敏感层和悬臂梁的结构及应力分布示意图；
图4是本揭露实施例提供的氢敏感层和膜片组件的结构及应力分布图；
图5是本揭露实施例中磁电阻传感单元的堆叠结构示意图；
图6是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在悬臂梁的结构及应力分布示意图；
图7是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在膜片组件的结构及应力分布示意图；
图8是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在膜片组件的结构及应力分布示意图；
图9A-图9P是磁电阻传感单元的自由层处于不同起始磁矩时在拉压应力作用下的旋转角度图；
图10A-图10D是自由层起始磁矩角度和旋转角度在拉应力和压应力作用下的圆周分布图；
图11是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在悬臂梁的结构及应力分布示意图；
图12是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在悬臂梁的结构及应力分布示意图；
图13是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在膜片组件的结构及应力分布示意图；
图14是本揭露实施例提供的推挽式磁阻应力传感器电桥及其在膜片组件的结构及应力分布示意图；
图15A-图15F是自由层起始磁矩角度和旋转角度在拉应力和压应力作用下的圆周分布图；
图16是本揭露实施例提供的参考式磁阻应力传感器电桥及其在悬臂梁的结构及应力分布示意图；
图17是本揭露实施例提供的参考式磁阻应力传感器电桥及其在膜片组件的结构及应力分布示意图；
图18是本揭露实施例提供的参考式磁阻应力传感器电桥及其在膜片组件的结构及应力分布示意图；
图19A-图19D是自由层起始磁矩角度和旋转角度在参考拉压应力作用下的圆周分布图；
图20A-图20D是磁阻应力传感器电桥的桥式结构示意图。
具体实施方式
为使本揭露的目的、技术方案和优点更加清楚，以下将参照本揭露实施例中的附图，通过实施方式清楚、完整地描述本揭露的技术方案，显然，所描述的实施例是本揭露一部分实施例，而不是全部的实施例。基于本揭露中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本揭露保护的范围。
参考图1所示，为本揭露实施例提供的一种基于电隔离磁阻应力敏感元件的氢气传感器的示意图。本实施例提供的氢气传感器包括：可变形基板1；位于可变形基板1上的磁阻应力传感器电桥2、覆盖磁阻应力传感器电桥2的电隔离层3以及位于电隔离层3上的磁屏蔽层4；位于可变形基板1上方的氢敏感层5，氢敏感层5在可变形基板1所在平面的正投影覆盖电隔离层3，氢敏感层5用于吸附或脱附氢气以发生膨胀或收缩形变并引起可变形基板1的应力变化，磁阻应力传感器电桥2用于根据可变形基板1的应力变化进行氢气浓度测量。
本实施例中，可选可变形基板1为任意一种可变形的膜层或基板，其中原始状态下，可变形基板1为平面状态，形变状态下，可变形基板1发生形变并产生应力变化。可选可变形基板1为悬臂梁；或者，可变形基板为膜片组件，膜片组件包括框架和封装在框架中的膜片，磁阻应力传感器电桥设置在膜片上。
本实施例中，可变形基板1上设置有磁阻应力传感器电桥2，磁阻应力传感器电桥2包括磁电阻传感单元，磁阻应力传感器电桥2上覆盖有电隔离层3以及位于电隔离层3上的磁屏蔽层4。电隔离层3可实现磁阻应力传感器电桥2的电源环境与外部环境之间的电绝缘隔离，尤其是在氢气环境下实现氢气环境和电源环境的隔离，避免氢气发生爆炸，提高产品测试安全性。磁屏蔽层4可以隔离外部环境的磁场与磁阻应力传感器电桥2，避免外部环境的磁场对磁阻应力传感器电桥2的影响，使得磁阻应力传感器电桥2主要采集可变形基板1的形变信号，提高磁阻应力传感器电桥2的测试准确性。可选磁阻应力传感器电桥2为隧道磁阻应力传感器电桥，可选电隔离层为任意一种可实现电绝缘隔离的膜层，可选磁屏蔽层为任意一种可实现电磁屏蔽的膜层。
本实施例中，可变形基板1上方设置有氢敏感层5，可选如图1所示氢敏感层5贴覆在磁屏蔽层4上，在其他实施例中还可选氢敏感层直接贴覆在可变形基板上。氢敏感层5在可变形基板1所在平面的正投影覆盖电隔离层3，则氢敏感层5吸附或脱附氢气发生的形变可使得其覆盖区域的可变形基板1发生形变，进而位于其覆盖区域的磁阻应力传感器电桥2可根据可变形基板1的应力变化进行氢气浓度测量。其中氢敏感层5吸附氢气会发生膨胀形变，氢敏感层5脱附氢气会发生收缩形变。可选，氢敏感层采用非Pd的储氢类金属或合金，能够和氢气反应形成氢化物，导致晶格常数增加，体积和长度增加，在和衬底形成薄膜结构时，能够在接触的衬底表面形成拉应力，并在未接触的衬底表面形成压应力。可选氢敏感层包括AB 5、AB 3、AB 2、AB和A 2B型金属间化合物中的至少一种，其中，A代表强金属氢化物形成元素，B代表过渡金属元素。可选A包括稀土金属、Ca、Mg、Zr或Ti，B包括Ni、Co、Fe、Mn或Cr。
如图1所示可选磁阻应力传感器电桥2可以位于可变形基板1的上表面。在其他实施例中还可选磁阻应力传感器电桥可以位于可变形基板的下表面，或者，在其他实施例中还可选磁阻应力传感器电桥同时分布在可变形基板的上表面和下表面。可以理解，无论磁阻应力传感器电桥设置在可变形基板的一侧表面上还是两侧表面上，磁阻应力传感器电桥 上均依次层叠设置有电隔离层和磁屏蔽层。
可选磁阻应力传感器电桥2具有电传输端口组件7，电传输端口组件7与可变形基板1直接连接，密封胶8将电传输端口组件7密封在可变形基板7上。其中，可变形基板7包括衬底6，电传输端口组件7包括磁阻应力传感器电桥2的电源端口、地端口和输出端口等各个端口，电传输端口组件7位于衬底6上方，并被密封胶8的胶体密封。下文将通过公式推导和描述应力与氢气浓度的对应关系。
在氢气气氛中，氢敏感层5将吸收氢气并变成金属氢化物，其体积和长度将会膨胀或者伸长；在非氢气气氛中，氢敏感层5中的氢化物将释放氢气并还原成金属及合金，则氢敏感层5的体积和长度恢复原始状态。氢敏感层5吸附或脱附氢气的特性类似于材料的热胀冷缩，可以给氢敏感层5定义一个氢膨胀系数γ，该氢膨胀系数γ与氢敏感层5的关系类似于热膨胀系数与材料的关系，氢膨胀系数γ表征氢敏感层吸附或脱附氢气的特性，氢膨胀系数γ的表达式(1)为：
Figure PCTCN2020123946-appb-000001
其中，L为氢敏感层的原长度，c为氢气浓度。显然，氢膨胀系数γ是氢气浓度c的函数，并与氢气浓度c呈正比。
图2和图3为氢敏感层的形变与可变形基板的应力分布示意图。可选可变形基板1为悬臂梁，悬臂梁1包括固定部1a和设置在固定部1a一侧的自由部1b，自由部1b的延伸方向为X轴方向，磁阻应力传感器电桥2设置在悬臂梁1的自由部1b。氢敏感层5和悬臂梁1形成双层结构，在此所述的双层是指氢敏感层5和悬臂梁1直接或间接形成双层结构，氢敏感层5的变形受到悬臂梁1的约束。
如图2所示，氢敏感层5位于悬臂梁1的上表面，氢敏感层5吸附氢气发生膨胀形变，导致悬臂梁1的自由部1b发生变形及悬臂梁1的截面11上内应力发生变化。悬臂梁1的自由部1b将产生向下的弯曲，并且悬臂梁1的上表面产生拉伸应力(也称拉应力)12，悬臂梁1的下表面产生压应力13，其中悬臂梁1内的10平面对应截面11中的0应变平面。
如图3所示，氢敏感层5位于悬臂梁1的下表面，氢敏感层5吸附氢气发生膨胀形变，导致悬臂梁1的自由部1b发生变形及悬臂梁1的截面11'上内应力发生变化。悬臂梁1的自由部1b将产生向上的弯曲，并且悬臂梁1的上表面产生压应力12'，悬臂梁1的下表面产生拉应力13'，其中悬臂梁1内的10'平面对应截面11'中的0应变平面。
其中，应力为σ，拉应力σ>0，压应力σ<0。拉应力可表征为氢敏感层对可变形基板表面的拉伸应力也可以表征为可变形基板表面对氢敏感层的拉伸应力，压应力可表征为氢敏感层对可变形基板表面的压缩应力也可以表征为可变形基板表面对氢敏感层的压缩应力。由于氢敏感层5变形受到悬臂梁1的约束，因此悬臂梁1在氢敏感层5中产生的应力σ可以用下式表示：
Figure PCTCN2020123946-appb-000002
其中，Es是悬臂梁的杨氏模量，ds是悬臂梁的厚度，C是悬臂梁弯曲半径，Vs是悬臂梁泊松比，σ f是氢敏感层的内应力，d f是氢敏感层的厚度。
另一方面，氢敏感层5中的应力σ还可以根据氢膨胀系数γ表示如下：
Figure PCTCN2020123946-appb-000003
其中E f为氢敏感层的杨氏模量，V f为氢敏感层泊松比。
因此，应力σ的大小与氢气浓度c成正比，磁阻应力传感器电桥通过测量应力σ的大小即可以得出氢气浓度的大小。
图4为氢敏感层的形变与可变形基板的应力分布示意图。可选可变形基板1为膜片组件，膜片组件包括框架61(3)和封装在框架61(3)中的膜片62(3)，磁阻应力传感器电桥设置在膜片62(3)上。可选磁阻应力传感器电桥位于膜片62(3)的上表面或者下表面，还可选磁阻应力传感器电桥同时位于膜片62(3)的上下表面，其中，磁阻应力传感器电桥包括多个磁电阻传感单元64(1)。对于膜片而言，在膜片62(3)上的膜层残余应力的作用下，镀有多膜层的膜片62(3)会发生挠曲，这种变形尽管很微小，但通过激光干涉仪或者面轮廓仪还是能够测量到挠曲的曲率半径，膜片62(3)上挠曲的程度反映了多膜层残余应力的大小，其中，多膜层具体是指形成在膜片上的薄膜膜层的集合。同样，应力公式如下：
Figure PCTCN2020123946-appb-000004
其中，t s和t f分别对应于膜层和膜片的厚度，r为曲率半径；E和v分别是膜片的弹性模量和泊松比。
同样，膜片上氢敏感层中的应力还正比于氢膨胀系数γ，其公式表示如下：
Figure PCTCN2020123946-appb-000005
其中E f为氢敏感层的杨氏模量，V f为氢敏感层泊松比。
因此，应力σ的大小与氢气浓度c成正比，磁阻应力传感器电桥通过测量应力σ的大小即可以得出氢气浓度的大小。
如上所述，悬臂梁和膜片组件都是在衬底上涂敷氢敏感层，氢敏感层吸氢之后导致体积和长度发生伸缩形变，如此氢敏感层的应力变化受到衬底的约束，导致衬底产生应力和挠度的变化，因此应力在膜片和悬臂梁表面所产生的应力方向和大小具有类似的关系。可以理解，悬臂梁的衬底为梁主体，膜片组件的衬底为膜片。如上多附图所示，悬臂梁和膜片组件的差异在于，悬臂梁是具有一固定端，而膜片是四周固定。
本揭露实施例中，提出一种基于电隔离的隧道磁阻应力敏感元件的氢气传感器，该氢气传感器包括可变形基板、位于可变形基板上的隧道磁阻应力传感器电桥、位于该TMR应力传感器电桥上的磁屏蔽层以及氢敏感层，氢敏感层用于吸附或脱附氢气而发生膨胀或收缩，从而引起可变形基板的应力的变化，磁阻应力传感器电桥采集到应力信号并将其转变成电信号，根据应力与氢气浓度的关系，实现对氢气浓度的测量。本实施例中，可变形基板可灵敏且实时的根据氢敏感层的变化而产生相应变化，提高了氢气传感器灵敏性和反应速率，并且测量方法简单，此外，电隔离层的设置可以实现氢气环境和磁阻应力传感器电桥之间的电隔离，从而保证了安全性，还能够应用在氢气浓度较大的环境中，提高测量 范围。提高了氢气传感器的各项新能。
示例性的，在上述技术方案的基础上，可选如图5所示可变形基板的长度方向为X轴方向，可变形基板的宽度方向为Y轴方向，磁阻应力传感器电桥包括多个磁电阻传感单元，磁电阻传感单元包括平行于X-Y平面的多膜层堆叠结构2'，该多膜层2'至少包括依次堆叠的钉扎层2e、参考层2d、势垒层2c、自由层2b和偏置层2a。
参考图1，示出了悬臂梁的侧视图和固定部的正视图，其中，X轴方向与悬臂梁的长度方向平行，Y轴方向与悬臂梁的宽度方向即固定部的宽度方向平行，X-Y平面即为该X轴方向与Y轴方向构成的平面。具体的，可变形基板设置磁阻应力传感器电桥的表面为长条形时，例如可变形基板为悬臂梁，该长条形的长边方向为可变形基板的长度方向即X轴方向，该长条形的短边方向为可变形基板的宽度方向即Y轴方向。可变形基板设置磁阻应力传感器电桥的表面为正方形时，例如可变形基板为膜片组件，其中的膜片为正方形，该正方形的相邻两边分别为可变形基板的长度方向即X轴方向和宽度方向即Y轴方向。或者，磁阻应力传感器电桥设置在可变形基板的表面，磁阻应力传感器电桥中磁电阻传感单元的排布方向为可变形基板的长度方向即X轴方向，磁阻应力传感器电桥中磁电阻传感单元的延伸方向为可变形基板的宽度方向即Y轴方向。
图5示出了磁阻应力传感器电桥的膜层堆叠结构，参考层2d的磁化方向由钉扎层2e来决定，而自由层2b的偏置方向由偏置层2a来决定。可选自由层2b为磁滞伸缩材料如CoFeB、CoFe或NiFe材料，具有高正磁致伸缩系数(λs＝30ppm)。隧道磁阻TMR应力传感器的原理在于，利用自由层2b的磁致伸缩效应，在应力的作用下，使得自由层2b的磁矩产生旋转，从而使得自由层2b和参考层2e之间的夹角α发生改变，磁电阻传感单元的电阻与自由层2b和参考层2e之间的夹角α的相互关系为：
Figure PCTCN2020123946-appb-000006
R AP和R P，R ⊥分别代表φ＝0°，90°和180°的电阻值。
应力在自由层中所产生的偏转等效于一个外磁场H σ：
Figure PCTCN2020123946-appb-000007
其中，λs为磁致伸缩系数，Ms是饱和磁化强度，拉应力σ>0时，H σ位于拉应力σ的方向上，压应力σ<0时，H σ位于垂直于压应力σ的方向上。
示例性的，在上述技术方案的基础上，可选可变形基板具有沿Z轴方向上排布的第一表面和第二表面；磁阻应力传感器电桥为推挽桥式结构，磁阻应力传感器电桥包括推磁电阻传感单元和挽磁电阻传感单元；推磁电阻传感单元设置在第一表面上，挽磁电阻传感单元设置在第二表面上，推磁电阻传感单元和挽磁电阻传感单元承受相同幅度且方向相反的应力。可选可变形基板为悬臂梁或膜片组件，在此所述的第一表面和第二表面均平行于X-Y平面，Z轴方向垂直于X-Y平面，其中，推磁电阻传感单元和挽磁电阻传感单元位于可变形基板的相对的两个表面上，例如推磁电阻传感单元位于可变形基板的上表面以及挽 磁电阻传感单元位于可变形基板的下表面，或者，推磁电阻传感单元位于可变形基板的下表面以及挽磁电阻传感单元位于可变形基板的上表面。在下文中详细描述基于两种可变形基板的氢气传感器的结构和工作原理。
图6为推挽式磁阻应力传感器电桥及其在悬臂梁上的结构及应力分布图。氢敏感层5位于悬臂梁1的上表面，推磁电阻传感单元20和挽磁电阻传感单元21分别位于悬臂梁1的上方和下方，对应的电隔离层3(1)覆盖推磁电阻传感单元20的表面，电隔离层3(2)覆盖挽磁电阻传感单元21的表面，磁屏蔽层4(1)和4(2)分别位于推磁电阻传感单元20和挽磁电阻传感单元21的表面以上。
假设氢敏感层5的厚度df远小于悬臂梁1的厚度ds，则0应力平面10位于悬臂梁1的中间位置ds/2，则推磁电阻传感单元20和挽磁电阻传感单元21所受的应力大小相同，方向相反。可选推磁电阻传感单元20受到拉应力12且拉应力σ1>0，挽磁电阻传感单元21受到压应力13且压应力σ2<0，拉应力12和压应力13的方向相反且大小相同，即σ1＝-σ2。
在其他实施例中，还可选氢敏感层位于悬臂梁的下表面，或者，氢敏感层覆盖挽磁电阻传感单元的上方。
图7为推挽式磁阻应力传感器电桥及其在膜片上的结构及应力分布图。膜片组件包括外围框架(未标示)和外围框架限定的膜片1(21)。氢气传感器还包括位于膜片1(21)上的推磁电阻传感单元20(21)以及电隔离层3(21)，位于膜片1(21)下方的挽磁电阻传感单元21(21)以及电隔离层31(21)，以及位于推磁电阻传感单元20(21)上方的磁屏蔽层4(21)和位于挽磁电阻传感单元21(21)上方的磁屏蔽层41(21)，以及位于磁屏蔽层4(21)上的氢敏感层5(21)，此时氢敏感层5(21)在吸收氢气后发生体积膨胀或者伸长，膜片将发生向上弯曲。
假设氢敏感层的厚度远小于膜片的厚度，则0应力平面位于膜片的中间位置，则推磁电阻传感单元和挽磁电阻传感单元所受的应力大小相同，方向相反。即σ1＝-σ2。
图8为推挽式磁阻应力传感器电桥及其在膜片上的结构及应力分布图。膜片组件包括外围框架(未标示)和外围框架限定的膜片1(23)。氢气传感器还包括位于膜片1(23)上的推磁电阻传感单元20(23)以及电隔离层3(23)，位于膜片1(23)下方的挽磁电阻传感单元21(23)以及电隔离层31(23)，以及位于推磁电阻传感单元20(23)上方的磁屏蔽层4(23)和位于挽磁电阻传感单元21(23)上方的磁屏蔽层41(23)，以及位于磁屏蔽层41(23)上的氢敏感层5(23)，此时氢敏感层5(23)在吸收氢气后发生体积膨胀或者伸长，膜片将发生向下弯曲。假设氢敏感层的厚度远小于膜片的厚度，则0应力平面位于膜片的中间位置，则推磁电阻传感单元和挽磁电阻传感单元所受的应力大小相同，方向相反。即σ1＝-σ2。
可选推磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α；推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩同时顺时针旋转或者同时逆时针旋转相同角度得到对应的钉扎层磁矩，挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为90-α或270-α；或者，推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩的旋转方向不同且旋转角度相同，挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为90+α或270+α；α取值0°到360°的范围内，其中，自由层采用具有正磁致伸缩系数的材料且承受拉应力或者采用具有负磁致伸缩系数的材料且承受压应力时α不为0°或者180°，自由层采用具有正磁致伸缩系数的材料且承受压应力或者采用具有负致伸缩系数 的材料且承受拉应力时α不为90°或者270°。需要说明的是，本揭露实施例中涉及角度的符号和数值，其单位均为度数°。
如图9A～9P所示为磁电阻传感单元的自由层处于不同起始磁矩角度时在拉压应力作用下的自由层磁矩旋转角度图。自由层的起始磁矩角度具体是指自由层的起始磁矩偏离Y轴(具体为+Y轴)的角度，承受应力之后，自由层的磁矩发生旋转。在此定义可变形基板的长度方向为X轴方向，定义可变形基板的宽度方向为Y轴方向，应力σ的轴向为X轴方向。
图9A中，自由层起始磁矩偏离Y轴α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β。图9B中，自由层起始磁矩偏离Y轴α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β1。图9C中，自由层起始磁矩偏离Y轴90-α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β1。图9D中，自由层起始磁矩偏离Y轴90-α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β。图9E中，自由层起始磁矩偏离Y轴90+α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β1。图9F中，自由层起始磁矩偏离Y轴90+α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β。图9G中，自由层起始磁矩偏离Y轴180-α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β。图9H中，自由层起始磁矩偏离Y轴180-α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β1。图9I中，自由层起始磁矩偏离Y轴180+α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β。图9J中，自由层起始磁矩偏离Y轴180+α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β1。图9K中，自由层起始磁矩偏离Y轴270-α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β1。图9L中，自由层起始磁矩偏离Y轴270-α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β。图9M中，自由层起始磁矩偏离Y轴270+α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β1。图9N中，自由层起始磁矩偏离Y轴270+α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β。图9O中，自由层起始磁矩偏离Y轴360-α角度，在承受拉应力σ>0时，自由层磁矩旋转角度为β。图9P中，自由层起始磁矩偏离Y轴360-α角度，在承受压应力σ<0时，自由层磁矩旋转角度为β1。如上所述，可知承受拉压应力之后，自由层磁矩旋转且旋转的角度值分别为β和β1。其旋转角度的计算过程如下：
拉应力σ>0在坐标系中等效于沿X轴方向的等效磁场Hσ，压应力σ<0等效于沿Y方向的等效磁场Hσ。自由层磁矩Mf与Y轴成不同起始偏转角时，具有各向异性磁场Hk，不考虑退磁场及其他偏置磁场对自由层磁矩的作用，自由层磁矩旋转一定角度后具有各项异性磁场Hef，其中Hef为Hk和Hσ磁场的矢量和，Hef是自由层磁矩最终的磁矩取向。以图9A所示自由层磁矩旋转角度β且自由层起始磁矩偏转角度α为例进行计算如下：
Figure PCTCN2020123946-appb-000008
Figure PCTCN2020123946-appb-000009
以图9B所示自由层磁矩旋转角度β1且自由层起始磁矩偏转角度α为例进行计算如下：
Figure PCTCN2020123946-appb-000010
Figure PCTCN2020123946-appb-000011
由于磁电阻传感单元的自由层和钉扎层磁矩之间的夹角φ在起始时都为90°，而自由层磁矩旋转角度为±β或者±β1，因此：Φ＝90°±β；Φ＝90°±β；显然，一般情况下β1并不等于β。
图9A-图9P中给出的钉扎层磁矩Mr和自由层磁矩Mf的相对关系为：将自由层磁矩Mf逆时针旋转90°可以得到钉扎层磁矩Mr，将自由层磁矩逆时针旋转得到钉扎层磁矩定义为CCW(Counterclockwise)；相反，将自由层磁矩Mf顺时针旋转90°可以得到钉扎层磁矩Mr，将自由层磁矩顺时针旋转得到钉扎层磁矩定义为CW(clockwise)。
表1列出了自由层磁矩处于不同起始偏转角时，自由层磁矩在拉应力和压应力情况下的自由层旋转磁矩，其中+代表自由层和钉扎层夹角增加，-代表自由层和钉扎层夹角减小。由表1可以看出，同一自由层起始偏转角，拉应力(σ>0)和压应力(σ<0)条件下，其自由层旋转角度幅度不同，分别为β1和β，或者β和β1，此外，其方向也不一样，分别为+和-，或者为-和+。表1如下：
角度 σ>0 σ<0
α +β -β1
90-α +β1 -β
90+α -β1 +β
180-α -β +β1
180+α +β -β1
270-α +β1 -β
270+α -β1 +β
360-α -β +β1
图10A-图10D为自由层起始磁矩角度和旋转角度在拉应力和压应力作用下的圆周分布图，其中β表征为实心圈，+β表征为实心圈中为+，-β表征为实心圈中为-；β1表征为空心圈，+β1表征为空心圈中为+，-β1表征为空心圈中为-。xxx no代表该处角度位置无效，内圈代表拉应力(σ>0)，外圈代表压应力(σ<0)，箭头代表自由层磁矩Mf在悬臂梁上的起始磁矩角度取向。
图10A为图9A-图9P中所代表的内圈TMR/外圈TMR＝CCWσ>0/CCWσ<0，图10B为图9A-图9P中所代表的内圈TMR/外圈TMR＝CWσ>0/CWσ<0，图10C为图9A-图9P中所代表的内圈TMR/外圈TMR＝CCWσ>0/CWσ<0，图10D为图9A-图9P中所代表的内 圈TMR/外圈TMR＝CWσ>0/CCWσ<0。
图6所示的氢气传感器结构，在拉应力σ>0和压应力σ<0的作用下推磁电阻传感单元和挽磁电阻传感单元的应力大小相同且方向相反，则推磁电阻传感单元和挽磁电阻传感单元的自由层和钉扎层的夹角变化值具有大小相等方向相反的特点。即要求推磁电阻传感单元在拉应力σ>0时自由层旋转角度为+β，挽磁电阻传感单元在压应力σ<0时自由层旋转角度为-β；或者，推磁电阻传感单元在拉应力σ>0时自由层旋转角度为+β1，挽磁电阻传感单元在压应力σ<0时自由层旋转角度为-β1。结合图10A-图10D的圆周分布图，则要求内圈和外圈中分别找到对应的+β和-β符号，或者找到+β1和-β1符号。
图6所示推挽式电桥结构，对应CCW/CCW和CW/CW结构即推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩同时顺时针旋转或者同时逆时针旋转相同角度得到对应的钉扎层磁矩，其所对应的推臂和挽臂的起始磁矩角度关系如下所示。
参考图10A所示，推磁电阻传感单元在拉应力σ>0时自由层旋转角度为+β，则查看其内圈，+β所对应的角度包括α和180+α；此时要求挽磁电阻传感单元在压应力σ<0时自由层旋转角度应为-β，则查看其外圈，-β所对应的角度包括90-α和270-α。参考图10B所示，推磁电阻传感单元在拉应力σ>0时自由层旋转角度为+β，则查看其内圈，+β所对应的角度包括360-α和180-α；此时要求挽磁电阻传感单元在压应力σ<0时自由层旋转角度应为-β，则查看其外圈，-β所对应的角度包括90+α和270+α。
参考图10A所示，推磁电阻传感单元在拉应力σ>0时自由层旋转角度为+β1，则查看其内圈，+β1所对应的角度包括90-α和270-α；此时要求挽磁电阻传感单元在压应力σ<0时自由层旋转角度应为-β1，则查看其外圈，-β1所对应的角度包括α和180+α。参考图10B所示，推磁电阻传感单元在拉应力σ>0时自由层旋转角度为+β1，则查看其内圈，+β1所对应的角度包括90+α和270+α；此时要求挽磁电阻传感单元在压应力σ<0时自由层旋转角度应为-β1，则查看其外圈，-β1所对应的角度包括360-α和180-α。
CCW/CCW和CW/CW结构推挽式磁电阻传感器电桥结构所对应的推臂和挽臂的起始磁矩角度关系如表2所示，对于CCWσ>0/CCWσ<0或者CWσ>0/CWσ<0两种TMR组态，当自由层旋转角度为+β和-β，或者为+β1和-β1时，对于任一推臂起始磁矩角度α，存在挽臂90-α和270-α与其对应。表2如下：
Figure PCTCN2020123946-appb-000012
类似的，图6所示推挽式电桥结构，对应CCW/CW和CW/CCW结构即推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩的旋转方向不同但旋转相同角度 得到对应的钉扎层磁矩，其所对应的推臂和挽臂的起始磁矩角度关系参考图10C和图10D，得到表3内容。其中，对于CCWσ>0/CWσ<0或者CWσ>0/CCWσ<0两种TMR组态，当自由层旋转角度为+β和-β，或者为+β1和-β1时，对于任一推臂起始磁矩角度α，存在挽臂90+α和270+α与其对应。表3如下：
Figure PCTCN2020123946-appb-000013
示例性的，在上述技术方案的基础上，可选可变形基板具有沿Z轴方向上排布的第一表面和第二表面；磁阻应力传感器电桥为推挽桥式结构，磁阻应力传感器电桥包括推磁电阻传感单元和挽磁电阻传感单元；推磁电阻传感单元和挽磁电阻传感单元同时设置在第一表面上或者同时设置在第二表面上，推磁电阻传感单元和挽磁电阻传感单元承受相同幅度且方向相同的应力。可选可变形基板为悬臂梁或膜片组件，在此所述的第一表面和第二表面均为X-Y平面，Z轴方向垂直于X-Y平面，其中，推磁电阻传感单元和挽磁电阻传感单元位于可变形基板的同一表面上，例如推磁电阻传感单元和挽磁电阻传感单元均位于可变形基板的下表面，或者，同时位于可变形基板的上表面。
图11为推挽式磁阻应力传感器电桥及其在悬臂梁上的结构及应力分布图。其中，推磁电阻传感单元20(11)和挽磁电阻传感单元20(12)均位于悬臂梁1(11)的上表面，并通过电隔离层3(11)覆盖于表面进行隔离，磁屏蔽层4(11)位于推磁电阻传感单元20(11)和挽磁电阻传感单元20(12)的上方用于屏蔽外磁场影响，氢敏感层5(11)位于最上方以便直接和氢气进行反应，10(11)为悬臂梁1(11)的0应变平面。氢敏感层5(11)形变会使悬臂梁1(11)产生向下的弯曲，并在推磁电阻传感单元20(11)和挽磁电阻传感单元20(12)中均将产生拉应力12(11)σ>0。
图12为推挽式磁阻应力传感器电桥及其在悬臂梁上的结构及应力分布图。其中，推磁电阻传感单元21(12)和挽磁电阻传感单元210(12)均位于悬臂梁1(12)的下表面，并通过电隔离层3(12)覆盖于表面进行隔离，磁屏蔽层4(12)位于推挽磁电阻传感单元21(12)和210(12)下方用于屏蔽外磁场影响，氢敏感层5(12)位于悬臂梁1(12)上表面以便直接和氢气进行反应，10(11)为悬臂梁0应变平面。悬臂梁将产生向下的弯曲并在推磁电阻传感单元20(11)和挽磁电阻传感单元20(12)中均将产生压应力13(12)σ<0。
图13为推挽式磁阻应力传感器电桥及其在膜片上的结构及应力分布图。其中，包括膜片1(20)，位于膜片1(20)上的推磁电阻传感单元20(20)以及挽磁电阻传感单元21(20)，以及电隔离层3(20)，位于推磁电阻传感单元20(20)和挽磁电阻传感单元21(20)上方的磁屏蔽层4(20)，以及位于最上层的氢敏感层5(20)，此时氢敏感层5(20)在吸收氢气后发生体积膨胀或者伸长，此时膜片将发生向上弯曲。
图14为推挽式磁阻应力传感器电桥及其在膜片上的结构及应力分布图。其中，包括膜片1(22)，位于膜片1(22)上的推磁电阻传感单元20(22)以及挽磁电阻传感单元21(22)，以及电隔离层3(22)，位于推磁电阻传感单元20(22)和挽磁电阻传感单元21(22)上方的磁屏蔽层4(22)，以及位于最下层的氢敏感层5(22)，此时氢敏感层5(22)在吸收氢气后发生体积膨胀或者伸长，膜片将发生向下弯曲。
可选的，推磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α；推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩同时顺时针旋转90°或者同时逆时针旋转90°得到对应的钉扎层磁矩，挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为180-α或360-α；或者，
推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩的旋转方向不同且旋转角度相同，挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α或180+α；α取值0°到360°的范围内，其中，自由层采用具有正磁致伸缩系数的材料且承受拉应力或者采用具有负磁致伸缩系数的材料且承受压应力时α不为0°或者180°，自由层采用具有正磁致伸缩系数的材料且承受压应力或者采用具有负致伸缩系数的材料且承受拉应力时α不为90°或者270°。
参考图15A-图15F为图11-图14所示氢气传感器的自由层起始磁矩角度和旋转角度在拉应力或压应力作用下的圆周分布图。图15A为CCWσ>0/CCWσ>0组态，图15B为CWσ>0/CWσ>0组态，图15C为CCWσ<0/CCWσ<0组态，图15D为CWσ<0/CWσ<0组态。其中，推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩同时顺时针旋转90°或者同时逆时针旋转90°得到对应的钉扎层磁矩。图15E为CWσ>0/CCWσ>0组态，图15F为CCWσ<0/CWσ<0组态。其中，推磁电阻传感单元的自由层磁矩和挽磁电阻传感单元的自由层磁矩的旋转方向不同且旋转角度相同。其圆周分布过程的分析方式与图9A-图9P类似，在此不再赘述。
表4为对应CCWσ>0/CCWσ>0，CWσ>0/CWσ>0，CCWσ<0/CCWσ<0，CWσ<0/CWσ<0四种组态的推挽式磁阻应力传感器电桥所对应的推臂和挽臂的起始磁矩角度关系表，当自由层旋转角度为+β和-β，或者为+β1和-β1时，对于任一推臂起始磁矩角度α，存在挽臂起始磁矩角度180-α和360-α与其对应。表4如下：
Figure PCTCN2020123946-appb-000014
表5为对应CWσ>0/CCWσ>0，CCWσ<0/CWσ<0两种组态的推挽式磁电阻传感器电桥结构二所对应的推臂和挽臂的起始磁矩角度关系表，当自由层旋转角度为+β和-β，或者为+β1和-β1时，对于任一推磁电阻传感单元起始磁矩角度α，存在挽磁电阻传感单元起始 磁矩角度α和180+α与其对应。表5如下：
Figure PCTCN2020123946-appb-000015
需要指出的是，在以上图示中，推磁电阻传感单元的自由层的起始磁矩角度α可以为0-360°范围内的任一角度，而挽磁电阻传感单元的自由层的起始磁矩角度如果超过360°，则可以通过减去360°的周期使得其值回到0-360°范围内，此外，对于拉应力σ>0，α≠90°和270°，对于压应力σ<0，α≠0°和180°。
示例性的，在上述技术方案的基础上，可选氢气传感器还包括：与氢敏感层同层的非氢敏感层；可变形基板包括悬臂梁或膜片组件；悬臂梁包括固定部以及设置在固定部两侧的参考悬臂梁和敏感悬臂梁，参考悬臂梁上设置有参考区域，敏感悬臂梁上设置有敏感区域；或者，膜片组件包括封装在框架中的参考膜片和敏感膜片，参考膜片上设置有参考区域，敏感膜片上设置有敏感区域；氢敏感层设置在位于敏感区域的磁屏蔽层上，非氢敏感层设置在位于参考区域的磁屏蔽层上。在此磁阻应力传感器电桥设置在可变形基板的同一侧表面，例如设置在上表面，在其他实施例中还可选设置在下表面。
可选可变形基板的参考区域和敏感区域位于同一平面；磁阻应力传感器电桥为参考桥式结构，磁阻应力传感器电桥包括参考磁电阻传感单元和敏感磁电阻传感单元；参考磁电阻传感单元设置在参考区域，敏感磁电阻传感单元设置在敏感区域。在此参考磁电阻传感单元和敏感磁电阻传感单元设置在可变形基板的同一侧表面，例如均设置在上表面或均设置在下表面。
如图16所示为参考桥式磁阻应力传感器电桥及其在悬臂梁上结构及应力分布图。该可变形基板包括两个悬梁，分别为敏感悬臂梁1(14)和参考悬臂梁1(15)，敏感磁电阻传感单元30(14)位于参考悬臂梁1(14)表面，参考磁电阻传感单元30(15)位于参考悬臂梁1(15)表面，电隔离层3(14)和3(15)分别位于敏感磁电阻传感单元30(14)和参考磁电阻传感单元30(15)表面，此外，氢敏感层5(14)和非氢敏感层5’(15)分别位于敏感悬臂梁1(14)和参考悬臂梁1(15)的顶层。氢敏感层5(14)遇到氢气将会发生尺寸变化，产生应力σ1，而非氢敏感层5’(15)不会发生变化，因此，两者构成参考桥式磁阻应力传感器电桥的敏感桥臂和参考桥臂。
图17为参考桥式磁阻应力传感器电桥及其在膜片组件上的结构及应力分布图。可变形基板包括：敏感膜片62(1)和参考膜片62(2)，其中敏感膜片62(1)四周位于衬底框架61(1)上，参考膜片62(2)四周位于衬底框架61(2)上，敏感磁电阻传感单元63(1)位于敏感膜片62(1)上，参考磁电阻传感单元63(2)位于参考膜片62(2)上，敏感 磁电阻传感单元63(1)和参考磁电阻传感单元63(2)电连接成参考桥式隧道磁阻应力传感器电桥。
图18为参考桥式磁阻应力传感器电桥及其在膜片组件上的结构的侧视图。其中，包括参考膜片1(17)，敏感膜片1(16)，以及位于参考膜片1(17)上的参考磁电阻传感单元20(16)，以及位于敏感膜片1(16)上的敏感磁电阻传感单元20(17)，以及电隔离层3(16)覆盖于参考磁电阻传感单元20(16)之间，以及电隔离层3(17)覆盖于敏感磁电阻传感单元20(17)之间，以及位于磁电阻传感单元20(16)和20(17)之上的磁屏蔽层4(16)和4(17)，以及位于最上方的氢敏感层5(16)和非氢敏感层5(17)，其中参考膜片1(16)和敏感膜片1(17)，磁屏蔽层4(16)和4(17)，电隔离层3(16)和3(17)为同层连续材料，而氢敏感层5(16)和非氢敏感层5(17)为同层但相互不连续的材料。
当氢气传感器暴置在空气中时，氢敏感层5(16)吸收氢气发生膨胀，但是受到敏感膜片1(16)的约束，从而膜片发生弯曲，此时敏感磁电阻传感单元20(16)感受压应力，当氢敏感层位于膜片的上方时，膜片向下弯曲，敏感磁电阻传感单元20(17)感受拉应力，当氢敏感层位于膜片的下方时，膜片向上弯曲，而非氢敏感层5(17)则不受氢气影响，不发生弯曲，感受本征应力。
可选的，参考磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α，敏感磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α；参考磁电阻传感单元的自由层磁矩和敏感磁电阻传感单元的自由层磁矩同时顺时针旋转或者同时逆时针旋转相同角度得到对应的钉扎层磁矩；α取值0°到360°的范围内，其中，自由层采用具有正磁致伸缩系数的材料且承受拉应力或者采用具有负磁致伸缩系数的材料且承受压应力时α不为0°或者180°，自由层采用具有正磁致伸缩系数的材料且承受压应力或者采用具有负致伸缩系数的材料且承受拉应力时α不为90°或者270°。
图19A-图19D为自由层起始磁矩角度和旋转角度在参考拉应力或参考压应力作用下的圆周分布图，由于隧道磁阻传感单元也有可能带来额外的应力，因此，参考磁电阻传感单元30(15)层中的残余应力近似为0，即σ≈0。参考磁电阻传感单元30(15)要选择与敏感磁电阻传感单元30(14)具有完全相同的位置和磁矩取向关系，以尽可能的消除残余应力的影响。基于此，敏感磁电阻传感单元/参考磁电阻传感单元的自由层起始磁矩角度取向如下：
图19A为CCWσ>0/CCWσ≈0，图19B为CCWσ<0/CCWσ≈0，图19C为CWσ>0/CWσ≈0，图19D为CWσ<0/CWσ≈0，因此敏感磁电阻传感单元和参考磁电阻传感单元的自由层取向可以为：在拉应力σ>0情况下，其自由层起始磁矩角度α≠0°和180°，在压应力σ<0情况下，其自由层起始磁矩角度α≠90°和270°。
对于上述实施例所述的推挽式磁阻应力传感器电桥，其结构如图20A-图20B所示，其中图20A为推挽式半桥结构磁阻应力传感器电桥，图20B为推挽式全桥结构磁阻应力传感器电桥。推磁电阻传感单元20和挽磁电阻传感单元21分别构成磁阻应力传感器电桥的推臂和挽臂。
对于上述实施例所述的参考式磁阻应力传感器电桥，其结构如图20C-图20D所示，其中图20C为参考式半桥结构磁阻应力传感器电桥，图20D为参考式全桥结构磁阻应力传感器电桥。敏感磁电阻传感单元30(14)和参考磁电阻传感单元30(15)分别构成磁阻应力 传感器电桥的敏感臂和参考臂。
对于磁阻应力传感器电桥，可选磁屏蔽层为软磁屏蔽层，其组成材料包含Co、Fe、Ni的软磁合金材料。可选电隔离层为光刻胶、Al 2O 3、SiN、SiO 2或者SiC。可选氢敏感层为AB 5，AB 3，AB 2，AB和A 2B型金属间化合物，其中A代表强金属氢化物形成元素，比如稀土金属、Ca、Mg、Zr或Ti，B代表过渡金属Ni、Co、Fe、Mn和Cr。
AB 5合金包括LaNi 5,RNi 5,R为稀土金属；MmNi 5，Mm为稀土混合物，包括48-50％Ce，32-34％La，13-14％Nd，4-5％Pr，1.5％其他稀土元素；富La的Mm称为Lm或者M1，典型Lm包括48％La，25％Ce，6％Pr，21％Nd和0.3％其他稀土元素；CaNi5；置换型AB 5多元素合金，AB 5中的A和B局部被其他金属置换，A中稀土金属相互置换，如CeNi 5,PrNi 5,NdNi 5置换LaNi 5，稀土金属和Ca互相置换，如Mm 1-xCa xNi 5，Mm可以部分被Ti，Zr，B，Cu置换，ANi 5中Ni原子部分被其他元素置换，如Co，Mn，Al，Cr，Fe，Cu，Tin，Si，B等。
AB 2金属间化合物合金包括：二元AB 2合金，如Zr基AB 2laves合金ZrM2(M＝V，Cr，Mn，Fe，Co，Mo)；三元和多元AB 2合金，用其他元素如Fe，Co，Ni，Al或Cu部分置换Cr，V或Mn，如Zr(FexCr 1-x) 2，Zr(Fe 0.75Cr 0.25) 2，Zr(Fe xMn 1-x) 2(x＝0-0.8)，Ti 0.98Zr 0.02V 0.43Fe 0.09Cr 0.05Mn 1.5，Ti 0.9Zr 0.1Mn 1.4V 0.2Cr 0.4，Ti 1+xCr 2-yMn y(x＝0.1-0.3，y＝0-1.0)，Ti xCr 2-yV y(x＝1.1-1.3，y＝0.5-1.0)。
AB合金包括：TiFe，TiCo，ZrNi；置换型AB合金，TiFe部分被过渡元素，如Mn，Cr，V，Co，Ni，Mo以及Cu等置换，TiFe 1-xMn x(x＝0.1-0.3)，TiFe 0.8Mn yAz(A＝Zr，Al)，TiFe 1-xNi yAz(A＝Al，Co，Cr，La，Mn，Mo，Nb，V，Zr)。
氢敏感层还包括Mg基合金，如Mg 2Ni，Mg 2Cu，La 2Mg 17，Mg-稀土合金：LnMg 12(Ln＝La，Ce，Mm)，Ln 2Mg 17(Ln＝La，Ce)，Ln 5Mg 41(Ln＝Ce)，其他二元Mg合金：Mg 17Ba，Mg 3Cd，Mg 3Sb 2，MgSn，MgZn，Mg 2Pb，Mg 2Ca，Mg 2Sn，Mg 2Si，MgLi，置换型Mg基合金：Mg 2Ni，Mg 2Cu，Mg 2Ni 0.75M 0.25(M＝V，Cr，Fe，Co，Zn)。
氢敏感层还包括V和V基本合金：V-Ti-M(M＝Fe，Cr，Mn，Ge)，如(V 0.9Ti 0.1) 1-xFe x(x＝0-0.075)，Ti-V-Mn，Ti-V-Cr，V-Ti-Ni。
需要指出的是，以上TMR应力敏感元件的自由层为正磁致伸缩系数λs>0，包括：CoFeB，CoFe，NiFe高磁致伸缩材料。实际上自由层还可以为负磁致伸缩系数λs<0，其区别仅在于λs<0，σ>0等效于λs>0，σ<0；λs<0，σ<0等效于λs>0，σ>0。对于推挽式磁电阻传感单元电桥的同相位CCW/CCW、CW/CW或者不同相位CCW/CW、CW/CCW以及参考磁电阻传感单元电桥的同相位CCW/CCW和CW/CW是磁电阻传感单元之间的起始相位关系没有影响，其差别在于λs>0时，承受拉应力σ>0的磁电阻传感单元起始角度不为0或180°，承受压应力σ<0的磁电阻传感单元起始角度不为90或270°。
注意，上述仅为本揭露的较佳实施例及所运用技术原理。本领域技术人员会理解，本揭露不限于这里所述的特定实施例，对本领域技术人员来说能够进行各种明显的变化、重新调整、相互结合和替代而不会脱离本揭露的保护范围。因此，虽然通过以上实施例对本揭露进行了较为详细的说明，但是本揭露不仅仅限于以上实施例，在不脱离本揭露构思的情况下，还可以包括更多其他等效实施例，而本揭露的范围由所附的权利要求范围决定。

Claims (13)

  1. 一种基于电隔离磁阻应力敏感元件的氢气传感器，其特征在于，包括：
    可变形基板；
    位于所述可变形基板上的磁阻应力传感器电桥、覆盖所述磁阻应力传感器电桥的电隔离层以及位于所述电隔离层上的磁屏蔽层；
    位于所述可变形基板上方的氢敏感层，所述氢敏感层在所述可变形基板所在平面的正投影覆盖所述电隔离层，所述氢敏感层用于吸附或脱附氢气以发生膨胀或收缩形变并引起所述可变形基板的应力变化，所述磁阻应力传感器电桥用于根据所述可变形基板的应力变化进行氢气浓度测量。
  2. 根据权利要求1所述的氢气传感器，其特征在于，所述可变形基板为悬臂梁；或者，
    所述可变形基板为膜片组件，所述膜片组件包括框架和封装在所述框架中的膜片，所述磁阻应力传感器电桥设置在所述膜片上。
  3. 根据权利要求2所述的氢气传感器，其特征在于，所述可变形基板的长度方向为X轴方向，所述可变形基板的宽度方向为Y轴方向，所述磁阻应力传感器电桥包括多个磁电阻传感单元，所述磁电阻传感单元包括平行于X-Y平面的多膜层堆叠结构，该多膜层至少包括依次堆叠的钉扎层、参考层、势垒层、自由层和偏置层。
  4. 根据权利要求3所述的氢气传感器，其特征在于，所述可变形基板具有沿Z轴方向上排布的第一表面和第二表面；
    所述磁阻应力传感器电桥为推挽桥式结构，所述磁阻应力传感器电桥包括推磁电阻传感单元和挽磁电阻传感单元；
    所述推磁电阻传感单元设置在所述第一表面上，所述挽磁电阻传感单元设置在所述第二表面上，所述推磁电阻传感单元和所述挽磁电阻传感单元承受相同幅度且方向相反的应力。
  5. 根据权利要求4所述的氢气传感器，其特征在于，所述推磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α；
    所述推磁电阻传感单元的自由层磁矩和所述挽磁电阻传感单元的自由层磁矩同时顺时针旋转或者同时逆时针旋转相同角度得到对应的钉扎层磁矩，所述挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为90-α或270-α；或者，
    所述推磁电阻传感单元的自由层磁矩和所述挽磁电阻传感单元的自由层磁矩的旋转方向不同且旋转角度相同，所述挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为90+α或270+α；
    α取值0°到360°的范围内，
    其中，所述自由层采用具有正磁致伸缩系数的材料且承受拉应力或者采用具有负磁致伸缩系数的材料且承受压应力时α不为0°或者180°，所述自由层采用具有正磁致伸缩系数的材料且承受压应力或者采用具有负致伸缩系数的材料且承受拉应力时α不为90°或者270°。
  6. 根据权利要求3所述的氢气传感器，其特征在于，所述可变形基板具有沿Z轴方向上排布的第一表面和第二表面；
    所述磁阻应力传感器电桥为推挽桥式结构，所述磁阻应力传感器电桥包括推磁电阻 传感单元和挽磁电阻传感单元；
    所述推磁电阻传感单元和所述挽磁电阻传感单元同时设置在所述第一表面上或者同时设置在所述第二表面上，所述推磁电阻传感单元和所述挽磁电阻传感单元承受相同幅度且方向相同的应力。
  7. 根据权利要求6所述的氢气传感器，其特征在于，所述推磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α；
    所述推磁电阻传感单元的自由层磁矩和所述挽磁电阻传感单元的自由层磁矩同时顺时针旋转90°或者同时逆时针旋转90°得到对应的钉扎层磁矩，所述挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为180-α或360-α；或者，
    所述推磁电阻传感单元的自由层磁矩和所述挽磁电阻传感单元的自由层磁矩的旋转方向不同且旋转角度相同，所述挽磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α或180+α；
    α取值0°到360°的范围内，
    其中，所述自由层采用具有正磁致伸缩系数的材料且承受拉应力或者采用具有负磁致伸缩系数的材料且承受压应力时α不为0°或者180°，所述自由层采用具有正磁致伸缩系数的材料且承受压应力或者采用具有负致伸缩系数的材料且承受拉应力时α不为90°或者270°。
  8. 根据权利要求3所述的氢气传感器，其特征在于，还包括：与所述氢敏感层同层的非氢敏感层；
    所述悬臂梁包括固定部以及设置在所述固定部两侧的参考悬臂梁和敏感悬臂梁，所述参考悬臂梁上设置有参考区域，所述敏感悬臂梁上设置有敏感区域；或者，
    所述膜片组件包括封装在所述框架中的参考膜片和敏感膜片，所述参考膜片上设置有参考区域，所述敏感膜片上设置有敏感区域；
    所述氢敏感层设置在位于所述敏感区域的所述磁屏蔽层上，所述非氢敏感层设置在位于所述参考区域的所述磁屏蔽层上。
  9. 根据权利要求8所述的氢气传感器，其特征在于，
    所述可变形基板的参考区域和敏感区域位于同一平面；
    所述磁阻应力传感器电桥为参考桥式结构，所述磁阻应力传感器电桥包括参考磁电阻传感单元和敏感磁电阻传感单元；
    所述参考磁电阻传感单元设置在所述参考区域，所述敏感磁电阻传感单元设置在所述敏感区域。
  10. 根据权利要求9所述的氢气传感器，其特征在于，所述参考磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α，所述敏感磁电阻传感单元的自由层起始磁矩偏离Y轴的角度为α；
    所述参考磁电阻传感单元的自由层磁矩和所述敏感磁电阻传感单元的自由层磁矩同时顺时针旋转或者同时逆时针旋转相同角度得到对应的钉扎层磁矩；
    α取值0°到360°的范围内，
    其中，所述自由层采用具有正磁致伸缩系数的材料且承受拉应力或者采用具有负磁致伸缩系数的材料且承受压应力时α不为0°或者180°，所述自由层采用具有正磁致伸缩系数的材料且承受压应力或者采用具有负致伸缩系数的材料且承受拉应力时α不为 90°或者270°。
  11. 根据权利要求1所述的氢气传感器，其特征在于，所述磁阻应力传感器电桥具有电传输端口组件，所述电传输端口组件与所述可变形基板直接连接，密封胶将所述电传输端口组件密封在所述可变形基板上。
  12. 根据权利要求1所述的氢气传感器，其特征在于，所述氢敏感层包括AB 5、AB 3、AB 2、AB和A 2B型金属间化合物中的至少一种，其中，A代表强金属氢化物形成元素，B代表过渡金属元素。
  13. 根据权利要求12所述的氢气传感器，其特征在于，所述A包括稀土金属、Ca、Mg、Zr或Ti，所述B包括Ni、Co、Fe、Mn或Cr。
PCT/CN2020/123946 2019-10-30 2020-10-27 一种基于电隔离磁阻应力敏感元件的氢气传感器 WO2021083137A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP20882910.1A EP4053551A4 (en) 2019-10-30 2020-10-27 HYDROGEN SENSOR BASED ON A VOLTAGE SENSITIVE ELEMENT WITH ELECTRICAL INSULATION AND MAGNETIC RESISTANCE
JP2022524943A JP2023500083A (ja) 2019-10-30 2020-10-27 電気的に隔絶されたトンネル磁気抵抗応力感知素子を利用した水素ガス・センサ
US17/755,180 US12066401B2 (en) 2019-10-30 2020-10-27 Hydrogen gas sensor utilizing electrically isolated tunneling magnetoresistive stress sensing elements

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201911048138.8A CN110646502A (zh) 2019-10-30 2019-10-30 一种基于电隔离磁阻应力敏感元件的氢气传感器
CN201911048138.8 2019-10-30

Publications (1)

Publication Number Publication Date
WO2021083137A1 true WO2021083137A1 (zh) 2021-05-06

Family

ID=69013871

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/123946 WO2021083137A1 (zh) 2019-10-30 2020-10-27 一种基于电隔离磁阻应力敏感元件的氢气传感器

Country Status (5)

Country Link
US (1) US12066401B2 (zh)
EP (1) EP4053551A4 (zh)
JP (1) JP2023500083A (zh)
CN (1) CN110646502A (zh)
WO (1) WO2021083137A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12066401B2 (en) 2019-10-30 2024-08-20 MultiDimension Technology Co., Ltd. Hydrogen gas sensor utilizing electrically isolated tunneling magnetoresistive stress sensing elements

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112410744B (zh) * 2020-11-09 2022-10-04 浙江工业大学 用于煤制气环境中的溅射薄膜敏感元件
CN112730598B (zh) * 2020-12-27 2024-02-02 北京工业大学 一种埋地钢质管道非开挖谐波磁场聚焦检测探头制作方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102565727A (zh) * 2012-02-20 2012-07-11 江苏多维科技有限公司 用于测量磁场的磁电阻传感器
CN102692287A (zh) * 2012-06-15 2012-09-26 扬州大学 一种基于磁电阻效应的新型应力传感器
CN103267955A (zh) * 2013-05-28 2013-08-28 江苏多维科技有限公司 单芯片桥式磁场传感器
CN106546644A (zh) * 2015-09-17 2017-03-29 英飞凌科技股份有限公司 气体敏感霍尔设备
US20170343522A1 (en) * 2016-05-30 2017-11-30 Kabushiki Kaisha Toshiba Gas detection device
CN109839411A (zh) * 2017-11-28 2019-06-04 株式会社东芝 气体传感器
CN110646502A (zh) * 2019-10-30 2020-01-03 江苏多维科技有限公司 一种基于电隔离磁阻应力敏感元件的氢气传感器
CN211043234U (zh) * 2019-10-30 2020-07-17 江苏多维科技有限公司 一种基于电隔离磁阻应力敏感元件的氢气传感器

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01307636A (ja) * 1988-06-06 1989-12-12 Sanyo Electric Co Ltd 水素濃度検出装置及び検出方法
JPH10170377A (ja) * 1996-12-11 1998-06-26 Toyota Motor Corp 圧力検出装置
US6596236B2 (en) * 1999-01-15 2003-07-22 Advanced Technology Materials, Inc. Micro-machined thin film sensor arrays for the detection of H2 containing gases, and method of making and using the same
US6889555B1 (en) * 1999-07-20 2005-05-10 Fidelica Microsystems, Inc. Magnetoresistive semiconductor pressure sensors and fingerprint identification/verification sensors using same
JP2002357489A (ja) * 2001-05-31 2002-12-13 Matsushita Electric Ind Co Ltd 応力センサー
JP2003037312A (ja) * 2001-07-23 2003-02-07 Matsushita Electric Ind Co Ltd 応力センサー
US7791150B1 (en) * 2004-09-25 2010-09-07 University Of Central Florida Research Foundation, Inc. Room temperature hydrogen sensor
DE102005010338B4 (de) * 2005-03-07 2007-01-25 Infineon Technologies Ag Kraftsensoranordnung mit magnetostriktiven Magnetowiderstandssensoren und Verfahren zur Ermittlung einer auf den Träger einer Kraftsensoranordnung wirkenden Kraft
CN1866007B (zh) * 2006-05-12 2010-06-09 中国科学院上海微系统与信息技术研究所 一种集成压阻二氧化硅悬臂梁超微量检测传感器、制作方法及应用
US7900527B1 (en) * 2006-12-22 2011-03-08 University Of Central Florida Research Foundation, Inc. Electrically deflected nanomechanical sensors
CN101936937A (zh) * 2010-07-06 2011-01-05 电子科技大学 一种微悬臂梁气体传感器及其制作方法
CN102928132B (zh) * 2012-10-22 2014-10-08 清华大学 隧道磁阻压力传感器
JP6223761B2 (ja) * 2013-09-20 2017-11-01 株式会社東芝 歪検知素子、圧力センサ、マイクロフォン、血圧センサおよびタッチパネル
JP2016161410A (ja) * 2015-03-02 2016-09-05 株式会社東芝 歪検出素子、圧力センサ及びマイクロフォン
CN104749223B (zh) * 2015-04-15 2017-10-20 海卓赛思（苏州）传感技术有限公司 一种用于油浸式变压器氢气浓度在线监测的氢气传感器及其使用方法
US20190025385A1 (en) 2015-09-17 2019-01-24 Infineon Technologies Ag Gas-sensitive hall device
CN105424238B (zh) * 2015-12-08 2018-07-27 北京金风科创风电设备有限公司 应力应变传感器
WO2018104936A1 (en) * 2016-12-06 2018-06-14 Ramot At Tel-Aviv University Ltd. Gas detection technique
JP6470353B2 (ja) * 2017-07-04 2019-02-13 株式会社東芝 歪検知素子、センサ、マイクロフォン、血圧センサ及びタッチパネル
CN109283228B (zh) * 2018-11-19 2024-07-23 江苏多维科技有限公司 一种基于磁阻元件的氢气传感器及其检测氢气的方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102565727A (zh) * 2012-02-20 2012-07-11 江苏多维科技有限公司 用于测量磁场的磁电阻传感器
CN102692287A (zh) * 2012-06-15 2012-09-26 扬州大学 一种基于磁电阻效应的新型应力传感器
CN103267955A (zh) * 2013-05-28 2013-08-28 江苏多维科技有限公司 单芯片桥式磁场传感器
CN106546644A (zh) * 2015-09-17 2017-03-29 英飞凌科技股份有限公司 气体敏感霍尔设备
US20170343522A1 (en) * 2016-05-30 2017-11-30 Kabushiki Kaisha Toshiba Gas detection device
CN109839411A (zh) * 2017-11-28 2019-06-04 株式会社东芝 气体传感器
CN110646502A (zh) * 2019-10-30 2020-01-03 江苏多维科技有限公司 一种基于电隔离磁阻应力敏感元件的氢气传感器
CN211043234U (zh) * 2019-10-30 2020-07-17 江苏多维科技有限公司 一种基于电隔离磁阻应力敏感元件的氢气传感器

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4053551A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12066401B2 (en) 2019-10-30 2024-08-20 MultiDimension Technology Co., Ltd. Hydrogen gas sensor utilizing electrically isolated tunneling magnetoresistive stress sensing elements

Also Published As

Publication number Publication date
JP2023500083A (ja) 2023-01-04
EP4053551A4 (en) 2023-12-06
US20220373513A1 (en) 2022-11-24
CN110646502A (zh) 2020-01-03
US12066401B2 (en) 2024-08-20
EP4053551A1 (en) 2022-09-07

Similar Documents

Publication Publication Date Title
WO2021083137A1 (zh) 一种基于电隔离磁阻应力敏感元件的氢气传感器
JP7134531B2 (ja) 磁気抵抗水素センサ、およびその感知方法
Liu et al. Self‐powered piezoionic strain sensor toward the monitoring of human activities
Lu et al. First-principles study of magnetic properties of L 1 0-ordered MnPt and FePt alloys
Liu et al. Germanium‐Based Electrode Materials for Lithium‐Ion Batteries
Gaal et al. Pressure dependence of the resistivity of single-wall carbon nanotube ropes
Ota et al. CoFeB/MgO-based magnetic tunnel junction directly formed on a flexible substrate
WO2021036867A1 (zh) 一种基于电隔离隧道磁阻敏感元件的氢气传感器
Barai et al. Mechano-electrochemical stochastics in high-capacity electrodes for energy storage
Fan et al. Density functional theory study of Cu-doped BNNT as highly sensitive and selective gas sensor for carbon monoxide
CN211043234U (zh) 一种基于电隔离磁阻应力敏感元件的氢气传感器
Shiu et al. D matter
Hasan et al. Pressure-dependent physical properties of cubic SrBO3 (B= Cr, Fe) perovskites investigated by density functional theory
Rathore et al. Bending fatigue damage reduction in indium tin oxide (ITO) by polyimide and ethylene vinyl acetate encapsulation for flexible solar cells
WO2022123472A1 (en) Magnetoresistive element for sensing a magnetic field in a z-axis
Xiong et al. First principles study of B 7 N 5 as a high capacity electrode material for K-ion batteries
Siriwardane et al. Engineering magnetic anisotropy and exchange couplings in double transition metal MXenes via surface defects
Stashkova et al. Hydrogen ordering in rare-earth intermetallic (Er, Tb) Fe 2 compounds with giant spontaneous magnetostriction
Nakamura et al. Water adsorption on ap (2× 2)-Ni (111)–O surface studied by surface x-ray diffraction and infrared reflection absorption spectroscopy at 25 and 140K
Yang et al. Structural, electronic, mechanical and thermodynamic properties of U–Si intermetallic compounds: A comprehensive first principles calculations
CN115968246A (zh) 基于磁性多层膜结构的反常能斯特效应热电器件
US11751483B2 (en) Spin diode devices
Tzeng et al. Experimental electronic structure of Be 2 C
CN113503990A (zh) 一种基于二维材料量子隧穿的高灵敏压力传感器
Bulaev et al. Magnetic response for an ellipsoid of revolution in a magnetic field

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20882910

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2022524943

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2020882910

Country of ref document: EP

Effective date: 20220530