Abstract: A rapid thermal processing method and apparatus used for programming the pinned layer of spintronic devices, the apparatus comprising a rapid thermal annealing light source, a reflective cover, a magnet, a wafer, and a substrate. The light source is used for heating the substrate. The reflective cover at least comprises a transparent insulating layer and a reflective layer. The magnet is used to produce a constant magnetic field. An antiferromagnetic layer on a wafer may be locally programmed by controlling the exposure time, for heating a specific area on the wafer to a temperature above the blocking temperature of the antiferromagnetic layer, and then turning off the magnetic field after the heating area has cooled in the presence of the applied magnetic field. This rapid thermal processing method is used to improve the spatial resolution of laser annealing. It provides excellent performance, and it is suitable for mass production.

Abstract: A low-noise magnetoresistive sensor includes a substrate and an array of magnetic modulation structures on the substrate. The structure includes upper and lower soft ferromagnetic layers and a conductive metal layer in the middle. The two ends of the structure are connected to form a two-port excitation coil. Adjacent structures have opposite current directions. A magnetoresistive sensing unit is located above or below and is centered in the gap between the structures. The sensitive direction of the sensing units is perpendicular to a long direction of the structures. An array of sensing units is electrically connected to form a magnetoresistive sensor, and the sensor is connected to the sensor bond pads. When measuring an external magnetic field, an excitation current is applied to the excitation coil, and the output of the voltage or current signal of the magnetoresistive sensor is demodulated to produce a low-noise voltage signal.

Abstract: A digital liquid-level sensor comprises a non-magnetic conduit, a floater provided outside the non-magnetic conduit and capable of axially moving along the non-magnetic conduit, and a permanent magnet fixed on the floater. The non-magnetic conduit further comprises a switch unit and an encoding unit. The switch unit comprises at least one tunneling magnetoresistance switch which is turned on or turned off under the effect of the magnetic field produced by the permanent magnet; and the encoding unit comprises at least one encoder, of which an input end receives an on/off signal from the tunneling magnetoresistance switch and outputs a digital signal indicating the position of the floater. The digital liquid-level sensor is of a small size; has low cost, low power consumption, high reliability, high sensitivity, high solution, long service life, and a good anti-interference capability; and can directly output the digital signal.

Abstract: A biaxial magnetoresistive angle sensor with a corresponding calibration method for magnetic field error correction, comprising two single-axis magnetoresistive angle sensors for detecting an external magnetic field in an X-axis direction and a Y-axis direction that are perpendicular to each other, a unit for calculating a vector magnitude of the voltage outputs of the single-axis magnetoresistive angle sensors along the X axis and the Y axis in real time, a unit for calculating a difference between a known calibration vector magnitude and the measured vector magnitude, a unit for dividing the difference by the square root of 2 in order to calculate an error signal, a unit for adding the error signal to the X-axis output and the Y-axis output respectively or subtracting the error signal from the X-axis output and the Y-axis output in order to calculate the calibrated output signals of the X-axis and the Y-axis angle sensors, a unit for calculating an arc tangent of a factor obtained by dividing the calibrated

Abstract: A three-axis upstream-modulated low-noise magnetoresistive sensor, comprising an X-axis magnetoresistive sensor (100), a Y-axis magnetoresistive sensor (110), and a Z-axis magnetoresistive sensor (120), wherein the X, Y, and Z-axis magnetoresistive sensors respectively comprise X, Y, and Z-axis magnetoresistive sensing unit arrays, X, Y, and Z-axis soft ferromagnetic flux concentrator arrays, and X, Y, and Z-axis modulator wire arrays. The X, Y, and Z-axis magnetoresistive sensing unit arrays are electrically interconnected into X, Y, and Z-axis magnetoresistive sensing bridges respectively. The X, Y, and Z-axis modulator wire arrays are electrically interconnected into individual two-port X, Y, and Z-axis excitation coils. In order to measure external magnetic fields, the two-port X, Y, and Z-axis excitation coils separately supplied with high-frequency alternating current at a frequency f, from a current supply.

Abstract: A resettable bipolar switch sensor is disclosed which comprises a bipolar magnetic hysteresis switch sensor, a reset coil, an ASIC switch circuit and a power reset circuit. The bipolar magnetic hysteresis switch sensor comprises a substrate and a magnetoresistive sensing arm located on the substrate. The magnetoresistive sensing arm is of a two-port structure composed of one or more magnetoresistive sensing unit strings arranged in series, parallel, or series-parallel. The magnetization direction of a free layer of a TMR magnetoresistive sensing unit is determined by an anisotropy field Hk, and together with the magnetization direction of a reference layer and the applied magnetic field, it can orient in an N or S direction. The reset coil is located between the substrate along with the magnetoresistive sensing unit, or it is located on a lead frame below the substrate. The direction of the reset magnetic field is either N or S.

Abstract: A magnetoresistive sensor with encapsulated initialization coil comprises a packaging structure, at least one pair of sensor chips, a spiral initialization coil, a set of wire bonding pads, an ASIC specific integrated circuit and an encapsulation layer. The spiral initialization coil is located on a PCB substrate of the encapsulation structure. Each set of sensor chips comprises two sensor chips, wherein each of the sensor chips comprises two groups of magnetoresistive sensing unit strings. The magnetoresistive sensing unit strings located on the sensor chip are connected to form a magnetoresistive sensor bridge. The application specific integrated circuit, ASIC and the magnetoresistive sensor bridge are electrically interconnected. The sensor chips are located above the spiral initialization coil placed circumferentially along the surface of the spiral initialization coil. The wire bonding pad and the ASIC are electrically interconnected.

Abstract: A balanced magnetoresistive frequency mixer comprises a first spiral coil, a second spiral coil, a balanced magnetoresistive sensor bridge, and a magnetic shielding layer. The coils are located between the magnetic shielding layer and the sensor bridge. The sensor bridge comprises a magnetoresistive full bridge consisting of four bridge arms and a balancing bridge arm connected to the power supply end of the full bridge. The four bridge arms contain pairs located in a first sub region and a second sub region above or below the first spiral coil, the balancing arm is located in a third sub region above or below the second spiral coil, a first frequency signal is input into the first spiral coil, a second frequency signal is input into the second spiral coil, and a frequency-mixed signal is output from a signal output end of the full bridge.

Abstract: A magnetoresistive sensor with a compensating coil comprising a silicon substrate, collection of MR sensor units disposed on the silicon substrate, collection of rectangular soft ferromagnetic flux concentrators, serpentine compensating coil, connecting circuit, and collection of bond pads used for electrical connections. The MR sensor units are interconnected to form a push-pull sensor bridge. The MR sensor units are disposed below the gap between two adjacent soft ferromagnetic flux concentrators. The serpentine compensating coil has a positive current strap over the MR sensor units and a negative current strap under the soft ferromagnetic flux concentrators. The MR sensor bridge and the serpentine compensating coil are connected through bond pads and covered with an encapsulation structure. The magnetoresistive sensor also comprises a spiral initialization coil placed on a substrate within the encapsulating structure.

Abstract: A direct-read meter capable of eliminating magnetic interference of adjacent rotating wheels, comprising N coaxial rotating wheel permanent magnets and corresponding magnetic angle sensors, a sampling element, a storage element, and a computation element. The magnetic angle sensors sense a linear superposition of the magnetic field from the intended permanent magnet rotating wheel and the interfering magnetic fields from the other rotating wheel permanent magnets. The sampling element samples the output signals of the N magnetic angle sensors to form a N*1 raw signal matrix [V/Vp]k(i)raw. The storage element stores an N*N correction matrix [Cij]; and the computation element computes the correction signal matrix [V/Vp]kcorr(i)=[V/Vp]k(i)raw?sum{C(i, j)*[V/Vp]k(j)raw}, thus eliminating the interfering magnetic field and permitting calculation of the rotation angle of the rotating wheel permanent magnets.

Abstract: A coin detection system comprises an excitation coil, a radial magnetic gradiometer, an axial magnetic gradiometer, a signal excitation source, a drive circuit, an analog front-end circuit and a processor. After the excitation coil is excited by the signal excitation source and the drive circuit, the excitation coil generates an excitation magnetic field parallel to the axial direction of a coin, and under the influence of the excitation magnetic field, the coin generates an induced magnetic field through eddy currents induced in the coin; the radial magnetic gradiometer and the axial magnetic gradiometer detect the magnetic field components of the magnetic field in the radial direction and the axial direction of the coin, and the detected signal is transmitted to the analog front-end circuit for amplification; the processor processes and then outputs the amplified signal transmitted by the analog front-end circuit, and the material, design, denomination, etc.

Abstract: A modulated magnetoresistive sensor consists of a substrate located on a substrate in an XY plane, magnetoresistive sensing elements, a modulator, electrical connectors, an electrical insulating layer, and bonding pads. The sensing direction of the magnetoresistive sensing elements is parallel to the X axis. The magnetoresistive sensing elements are connected in series into a magnetoresistive sensing element string. The modulator is comprised of multiple elongated modulating assemblies. The elongated modulating assemblies consist of three layers—FM1 layer, NM layer, and FM2 layer. The ends of the elongated modulating assemblies are electrically connected to form a serpentine current path. The electrical insulating layer is set between the elongated modulating assemblies and the magnetoresistive sensing elements to separate the elongated modulating assemblies from the magnetoresistive sensing elements.

Abstract: A dual Z-axis magnetoresistive angle sensor comprising a circular permanent magnet encoding disc, two Z-axis magnetoresistive sensor chips, and a PCB, two Z-axis magnetoresistive sensors are placed on the PCB. The magnetic sensing directions of the Z-axis magnetoresistive sensors are orthogonal to the substrate. Each Z-axis magnetoresistive sensor chip comprises a substrate and at least one magnetoresistive sensor located on the substrate. The magnetic field sensitive direction of the magnetoresistive sensor is perpendicular to the substrate. The magnetoresistive sensor comprises a flux concentrator and a magnetoresistive sensor unit. The magnetoresistive sensor unit is connected electrically into a push-pull structure. The push arm and pull arm of the magnetoresistive sensor are respectively located at two side positions equidistant from Y-axis central line and above or below the flux concentrator. The circular permanent magnet encoding disc has a magnetization direction parallel to the diameter direction.

Abstract: The present invention discloses a single-chip high-sensitivity magnetoresistive linear sensor, which comprises a substrate located in the X-Y plane and a soft ferromagnetic flux concentrator array located on the substrate. The soft ferromagnetic flux concentrator array comprises several soft ferromagnetic flux concentrators, wherein there is a gap between each two adjacent soft ferromagnetic flux concentrators. The +X and ?X magnetoresistive sensing unit array respectively comprises +X and ?X magnetoresistive sensing units located in the gaps. The +X and ?X magnetoresistive sensing units are electrically interconnected to form a push pull X-axis magnetoresistive sensor. Each of the magnetoresistive sensing units that have the same magnetic field sensing direction are arranged in adjacent locations. The magnetoresistive sensing units are all MTJ magnetoresistive sensor elements, and each has the same magnetic multi-layer film structure.

Abstract: A magnetoresistive sensor wafer layout scheme used for a laser writing system and laser scanning method are disclosed. The layout scheme comprises a magnetoresistive multilayer film including an antiferromagnetic pinning layer arranged into a rectangular array of sensor dice on the wafer surface. Pinning layers of magnetoresistive sensing units are magnetically oriented and directionally aligned by the laser writing system. Sensing units are electrically connected into bridge arms electrically connected into a magnetoresistive sensor. Magnetoresistive sensing units in the dice are arranged into at least two spatially-isolated magnetoresistive orientation groups. In the magnetoresistive orientation groups, pinning layers of the sensing units have an angle of magnetic orientation of 0-360 degrees. Angles of magnetic orientation of two adjacent magnetoresistive orientation groups are different.

Abstract: A low-noise magnetoresistive sensor having a multi-layer magnetic modulation structure consists of a substrate and a multi-layer magnetic modulation structure array located on the substrate. The modulation structure comprises two ferromagnetic layers, an upper and a lower layer, each comprised of a soft ferromagnetic material, and one layer of conductive metal in the middle. The two ends of the modulation structure are connected using conductive strips to form a two-port excitation coil. Adjacent modulation structures have opposite current directions. A magnetoresistive sensing unit is located above or below the modulation structures, centered in the gap between the modulation structures. The sensitive direction of the magnetoresistive sensing units is perpendicular to the long direction of the modulation structures. The magnetoresistive sensing unit array is electrically connected to form a magnetoresistive sensor, and the sensor is connected to the sensor bond pads.

Abstract: An integrated current sensor comprising a Z axis gradiometer and a lead frame primary coil, wherein the Z-axis gradiometer is a magnetoresistive Z-axis gradient sensor, comprising a substrate, with two elongated soft magnetic flux concentrators placed upon the substrate. The soft ferromagnetic flux concentrators are located above or below but displaced from a long-axis centerline equidistant from the magnetoresistive sensor strings, such that the combined magnetoresistive sensing unit detects the magnetic field perpendicular to the long-axis center line, and it is configured as a gradiometer sensor bridge. The lead frame serves as the primary coil, and the Z-axis gradiometer is placed above or below a cross-section of the current carrying portion of the lead frame, such that the current detection direction is parallel to the long-axis centerline. This sensor can detect currents of up to 5 to 50 A, it has low power consumption, small size, and fully integrated.

Abstract: A single-chip two-axis magnetoresistive angle sensor comprises a substrate located in an X-Y plane, a push-pull X-axis magnetoresistive angle sensor and a push-pull Y-axis magnetoresistive angle sensor located on the substrate. The push-pull X-axis magnetoresistive angle sensor comprises an X push arm and an X pull arm. The push-pull Y-axis magnetoresistive angle sensor comprises a Y push arm and a Y pull arm. Each of the X push, X pull, Y push arm, and Y pull arms comprises at least one magnetoresistive angle sensing array unit. The magnetic field sensing directions of the magnetoresistive angle sensing array units of the X push, X pull, Y push, and Y pull arms are along +X, ?X, +Y and ?Y directions respectively. Each magnetoresistive sensing unit comprises a TMR or GMR spin-valve having the same magnetic multi-layer film structure.

Abstract: A magnetoresistive sensor with a compensating coil comprising a silicon substrate, collection of MR sensor units disposed on the silicon substrate, collection of rectangular soft ferromagnetic flux concentrators, serpentine compensating coil, connecting circuit, and collection of bond pads used for electrical connections. The MR sensor units are interconnected to form a push-pull sensor bridge. The MR sensor units are disposed below the gap between two adjacent soft ferromagnetic flux concentrators. The serpentine compensating coil has a positive current strap over the MR sensor units and a negative current strap under the soft ferromagnetic flux concentrators. The MR sensor bridge and the serpentine compensating coil are connected through bond pads and covered with an encapsulation structure. The magnetoresistive sensor also comprises a spiral initialization coil placed on a substrate within the encapsulating structure.

Abstract: A single-chip off-axis magnetoresistive Z-X angle sensor and measuring instrument. The single-chip off-axis magnetoresistive Z-X angle sensor comprises a substrate located on an X-Y plane, at least one X-axis magnetoresistive sensor and at least one Z-axis magnetoresistive sensor, the X-axis magnetoresistive sensor and the Z-axis magnetoresistive sensor being located on the substrate. The X-axis magnetoresistive sensor and the Z-axis magnetoresistive sensor each comprise magnetoresistive sensing units and a flux concentrator, the magnetoresistive sensing units being electrically connected into a magnetoresistive bridge comprising at least two bridge arms. The Z-axis magnetoresistive sensor is a push-pull bridge structure, a push arm and a pull arm of the push-pull bridge structure being respectively located at positions equidistant from a Y-axis central line of the flux concentrator.