34 results about "Magnetization reversal" patented technology

The invention provides a synthetic antiferromagnetic memory cell driven by spin orbit moment without magnetic field assistance, and belongs to the technical field of magnetic memory, the synthetic antiferromagnetic memory cell comprises a magnetic tunnel junction of a multilayer film structure, the magnetic tunnel junction comprises a heavy metal layer and a synthetic antiferromagnetic free layer located on the heavy metal layer; the tunneling insulating layer is located on the synthetic antiferromagnetic free layer, the reference layer is located on the tunneling insulating layer, and the metal electrode layer is located on the reference layer; wherein the synthetic antiferromagnetic free layer comprises an inclined vertical magnetic layer, a non-magnetic metal layer and a coupling magnetic layer which are stacked in sequence, and the inclined vertical magnetic layer and the coupling magnetic layer are subjected to antiferromagnetic coupling through the middle non-magnetic metal layer; the inclined perpendicular magnetic layer has inclined perpendicular anisotropy. According to the invention, deterministic magnetization flipping driven by spin orbit moment and resistance state control of the magnetic tunnel junction memory cell without the assistance of an external magnetic field are realized.

Disclosed is an operation method of a neural network element using a Hall voltage. The neural network element has a hole pattern portion, and the hole pattern portion has a cross shape. When a pulse current is applied, horizontal magnetic anisotropy is formed in a ferromagnetic layer by means of spin-orbit torque, and when an external magnetic field in a direction perpendicular to the pulse current is applied, the inversion of magnetization occurs by means of additional torque. The movement of a magnetic domain wall is performed by the inversion of magnetization, spin electrons applied thereby are scattered, and a Hall voltage is generated according to the anomalous Hall effect. The generated Hall voltage increases according to the number of applications of the pulse current or pulse voltage.

This application discloses a magnetic tunnel junction memory device based on a bismuth selenide and nickel iodide heterojunction substrate. The memory includes, from top to bottom, a top electrode, a SOT-MTJ, and a substrate. The SOT-MTJ includes, from top to bottom, a reference layer, a tunneling layer, a heavy metal layer, and a free layer. The substrate is a Bi2Se3 and NiI2 heterojunction structure. Bi2Se3 facilitates the conversion of current into spin-orbit torque, enabling current-induced field-free magnetization reversal. NiI2 has vertical magnetic anisotropy, which can reduce the critical reversal current. An artificial antiferromagnetic structure (CoFeB / MgO / Ta / W / CoFeB) with vertical magnetic anisotropy is adopted, with Ta / W composite heavy metal as the coupling layer. The two antiferromagnetically coupled CoFeB layers switch between parallel and antiparallel states under the action of SOT. Both Ta and W have large spin Hall angles, which are very beneficial for generating spin-orbit torque to reverse the magnetic moment.

The invention discloses a memory, a manufacturing method thereof and electronic equipment. The memory comprises a memory unit located on a substrate; the storage unit comprises a switch unit and a magnetic tunnel junction; the magnetic tunnel junction is located on the side, away from the substrate, of the switch unit, the magnetic tunnel junction comprises a free layer, and the free layer comprises a ferromagnetic material with spin-orbit coupling capacity and flip symmetry breaking. According to the memory provided by the embodiment of the invention, magnetization overturning of the free layer can be realized without an external magnetic field.

A columnar three-dimensional magnetic storage unit and a writing method are disclosed. In the magnetic storage unit, a central nanopillar is a nanopillar structure made of a material having a spin-orbit coupling effect; a magnetic storage layer wraps an outer side of the central nanopillar; a magnetic free layer surrounds and contacts the central nanopillar, with a polarization direction of the magnetic free layer extending axially along the nanopillar structure, and the magnetization reversal of the magnetic free layer depending on spin-polarized electrons, whose polarization direction is circumferential, generated by the central nanopillar, a damping-like torque and a field-like torque generated by the spin-polarized electrons synergistically achieving the magnetization precessional reversal of the magnetic free layer; a magnetic tunneling layer wraps an outer side of the magnetic free layer; a magnetic pinned layer wraps an outer side of the magnetic tunneling layer.

The invention provides an ultra-low power consumption polymorphic spin nano device based on artificial antiferromagnetic structures, which comprises spin units arranged in an array, in a horizontal plane, each spin unit comprises an artificial antiferromagnetic structure arranged diagonally and an artificial ferromagnetic structure arranged diagonally, and the two artificial antiferromagnetic structures are connected with each other. The artificial antimagnet structure is an input end, and the artificial ferromagnetic structure is an output end; the artificial antiferromagnetic structure comprises a first ferromagnetic sub-layer, a first non-magnetic layer and a first top ferromagnetic layer which are sequentially arranged on one side of the electrode wire in the direction perpendicular to the horizontal plane; and the artificial ferromagnetic structure comprises a second non-magnetic layer, a second ferromagnetic sub-layer and a second top ferromagnetic layer which are sequentially arranged on one side of the electrode wire. According to the invention, the artificial antiferromagnetic structure is used as an input end, and the magnetization flipping field intensity is reduced by regulating and controlling the interlayer exchange coupling effect of the first ferromagnetic sub-layer, so that the driving current density of the spinning nano device is remarkably reduced, and the power consumption is further reduced.

A method for producing a spin current magnetization rotational element includes a stacking step of stacking, on one surface of a substrate, a magnetoresistance effect element having a first ferromagnetic metal layer having a fixed magnetization direction, a second ferromagnetic metal layer having a variable magnetization direction, and a non-magnetic layer sandwiched between the first ferromagnetic metal layer and the second ferromagnetic metal layer, and spin-orbit torque wiring which extends in a first direction, wherein an inclined surface non-parallel to the first direction is formed on at least a part of a surface of the spin-orbit torque wiring.

A spin current magnetization reversal element includes: a first ferromagnetic metal layer with a changeable magnetization direction, and a spin-orbit torque wiring, wherein a first direction is defined as a direction perpendicular to a surface of the first ferromagnetic metal layer, the wiring extends in a second direction intersecting the first and is bonded to a first surface of the first ferromagnetic metal layer, wherein the wiring includes a pure spin current generator which is bonded to the metal layer, and a low-resistance portion which is connected to both ends of the generator in the second direction and is formed of a material having a smaller electrical resistivity than the generator, and the generator is formed so that an area of a cross-section orthogonal to the first direction continuously and / or stepwisely increases as it recedes from a bonding surface bonded to the first ferromagnetic metal layer in the first direction.

The invention discloses a magnetic tunnel junction unit, a preparation method thereof, a memory, an access method and equipment, and belongs to the technical field of semiconductors. The magnetic tunnel junction unit comprises a track Hall function layer and an antiferromagnetic free layer which are sequentially arranged in the direction perpendicular to the substrate. Wherein the track Hall function layer is used for converting current flowing through the track Hall function layer into track flow; the antiferromagnetic free layer is used for converting the orbital flow into a spin flow and performing magnetization flipping based on the spin flow. The magnetic tunnel junction unit is high in control convenience, interference on data stored in the memory can be reduced based on the magnetic tunnel junction unit, the stability of the memory is improved, the preparation process of the magnetic tunnel junction unit is simplified, the size of the magnetic tunnel junction unit is reduced, and the integration density and the storage density of the memory are improved.

To provide a magnetic recording medium capable of improving magnetization inversion efficiency without giving new magnetization inversion energy with a simple structure, and to provide a magnetic recording device provided with the same.SOLUTION: According to an aspect of the present invention, there is provided a magnetic recording medium 10 capable of recording information by irradiation with circularly polarized light, the magnetic recording medium 10 including a substrate 11, an antiferromagnetic layer 12 provided on one surface side of the substrate 11, and a ferromagnetic layer 13 provided on a surface 12B of the antiferromagnetic layer 12 opposite to a surface 12A on the substrate 11 side.SELECTED DRAWING: Figure 2

The invention discloses a zero-field spin-orbit moment memory with a ferromagnetic layer component gradient structure and a preparation method thereof, the core structure of the memory comprises a CoFeB ferromagnetic layer with a vertical component gradient, and magnetic moments at two sides of a domain wall generate asymmetry in amplitude or orientation by regulating and controlling gradient distribution of Co, Fe and B elements and inducing non-uniform Dzyaloshiski-Moriya interaction (DMI); furthermore, domain wall chiral characteristics are weakened, a net effective field is formed, and deterministic magnetization overturning without assistance of an external magnetic field is finally realized. In the preparation process, a magnetron sputtering technology is adopted, a heavy metal strong spin orbit coupling layer, a vertical magnetic anisotropy magnetic free layer with component gradient, a tunnel barrier layer, a magnetic vertical reference layer, an artificial antiferromagnetic pinning layer and a covering layer are stacked in sequence, and a magnetic tunnel junction (MTJ) unit is prepared through annealing and micro-nano processing technologies. The invention provides an efficient solution for the research and development of controllable magnetic memories and logic devices, and has a wide application prospect in the field of high-density magnetic memories.

This application discloses a signal readout method and apparatus based on a Hall effect device array with lateral resistance, relating to the field of circuit technology. Each Hall effect device is provided with two power supply terminals and at least one Hall signal terminal. The method includes: changing the flip angle of the free magnetic layer of at least one Hall effect device using spin orbital moment, thereby setting the Hall resistance value of the corresponding Hall effect device to a desired target value; connecting the Hall signal terminals of several Hall effect devices in series to read the summed voltage; and connecting the Hall signal terminals of several Hall effect devices in parallel to read the summed current. The Hall effect device of this application can achieve current-induced out-of-plane magnetization reversal under shunt conditions; the flip angle can change the resistance value, thereby reducing the need for Hall effect devices with different resistance values; this application realizes that the Hall signal terminals of multiple Hall effect devices are connected in series to achieve voltage summation, or connected in parallel to achieve current summation.

This allows for even greater spin-orbit torque to be generated in SrRuO3. [Solution] This current-induced magnetization reversal element comprises a substrate 101 and a thin film 102 made of SrRuO3 crystals epitaxially grown on the substrate 101. The substrate 101 is made of a crystal whose lattice constant differs by 0.5% or more from the lattice constant of the pseudo-cubic crystal of SrRuO3, and whose main surface on which the thin film 102 is formed is a cubic (001) or pseudo-cubic (001) plane. In the thin film 102, the oxygen octahedron is rotated with respect to the crystal axis of the pseudo-cubic crystal of SrRuO3.

The magnetic memory device stabilizes magnetization reversal. A magnetic memory device includes: a first conductor layer extending in a first direction; a second conductor layer extending in the first direction and aligned with the first conductor layer in a second direction intersecting the first direction; a first magnetoresistive effect element electrically connected to the first conductor layer; a second magnetoresistive effect element electrically connected to the second conductor layer; and a third conductor layer extending in the second direction and in contact with the first magnetoresistive effect element. In a write operation for writing data to the first magnetoresistive effect element, a first current is applied to the first conductor layer, a second current is applied to the second conductor layer, and a third current is applied to the third conductor layer independently of the first current and the second current.

The invention discloses a Fe2O3 buffer layer-based magnetic random access memory capable of realizing directional overturning of a magnetization layer without an external magnetic field and driven by a vertical magnetic layer current, and belongs to the field of spintronics. The structure of the device sequentially comprises an antiferromagnetic layer Fe2O3, a spin current generation layer Pt, a magnetic layer Co with vertical anisotropy and a protective layer TaOx for preventing a thin film from being oxidized from bottom to top. Due to the addition of the antiferromagnetic layer Fe2O3, magnetization overturning can be induced to be free of external field. According to the invention, the insulated Fe2O3 is used as the buffer layer to be inserted into the Pt / Co system, so that not only can zero field flip be realized, but also the problem of increase of critical flip current of the device caused by a shunting effect due to introduction of the functional layer can be avoided. The invention provides a structure and a preparation process of a current-driven magnetization turnover device based on an insulating antiferromagnetic layer.

The application relates to a magnetic multilayer film and a preparation method and application thereof. The magnetic multilayer film comprises a substrate and a heavy metal layer, a ferromagnetic layer, a rare earth magnetic alloy layer, a rare earth metal layer, a light metal layer and a protective cover layer which are sequentially arranged on the substrate; the heavy metal layer is configured to generate spin current under the action of current and acts on the ferromagnetic layer in the form of spin-orbit torque; the light metal layer is configured to generate orbital current under the action of current; the rare earth metal layer and the rare earth magnetic alloy layer are configured to convert the orbital current into orbital torque and act on the rare earth magnetic alloy layer; the orbital torque and the spin-orbit torque synergistically act to reduce the critical current of magnetization reversal of the magnetic multilayer film. The magnetic multilayer film of the application realizes orbital torque synergistic driving, significantly reduces the critical current of magnetization reversal of the device, and is beneficial to the preparation of high-efficiency and low-power-consumption spintronic devices.

Provided is a magnetic recording medium having a high linear recording density.　This magnetic recording medium is a tape-like magnetic recording medium, and comprises a base and a magnetic layer containing magnetic particles. The average thickness of the magnetic recording medium is 5.30 μm or less. The average particle volume of the magnetic particles is 1.50 × 103 nm3 or less. When a signal is recorded in the magnetic layer at a recording wavelength of 739.2 nm, the sum (σ1 + σ2) of a peak variation σ1 at a magnetization reversal position, the peak variation being obtained by measuring a recorded portion of the signal by a magnetic force microscope, and a peak interval variation σ2 is 18.5 nm or less.

Disclosed methods include placing a semiconductor wafer containing MRAM devices into a first magnetic field that has a magnitude sufficient to magnetically polarize MRAM bits and has a substantially uniform field strength and direction over the entire area of the wafer. The method further includes placing the wafer in a second magnetic field having an opposite field direction, a substantially uniform field strength and direction over the entire area of the wafer, and magnitude less than a design threshold for MRAM bit magnetization reversal. The method further includes determining a presence of malfunctioning MRAM bits by determining that such malfunctioning MRAM bits have a magnetic polarization that was reversed due to exposure to the second magnetic field. Malfunctioning MRAM bits may further be characterized by electrically reading data bits, or by using a chip probe to read one or more of voltage, current, resistances, etc., of the MRAM devices.

The present application provides a kind of magnetoresistance effect element, in the magnetoresistance effect element, it has: magnetoresistance effect element, with the first ferromagnetic metal layer of fixed magnetization direction, and the second ferromagnetic metal layer of variable magnetization direction, and the non-magnetic layer being interposed by the first ferromagnetic metal layer and the second ferromagnetic metal layer;Spin-orbit torque wiring, it extends along the direction of the cross direction of the stacking direction of the magnetoresistance effect element, and is engaged with the above-mentioned second ferromagnetic metal layer, in the part of the above-mentioned magnetoresistance effect element and the above-mentioned spin-orbit torque wiring engagement, the current that flows in the above-mentioned magnetoresistance effect element and the current that flows in the above-mentioned spin-orbit torque wiring are combined or distributed.

The present invention provides a magnetic nano multi-ring storage device, a preparation method thereof, and an application. The magnetic nano multi-ring storage device includes: a substrate; and a unit attached to the substrate; wherein the unit is composed of nano-rings with overlapping ring edges or ring edges in contact connection. Since the device with overlapping ring edges has a relatively large exchange coupling strength, its hysteresis loop exhibits a three-step magnetization reversal process and a complex magnetic domain state; the hysteresis loops of the devices with ring edges in contact connection all show a two-step magnetization reversal behavior, and the magnetic domain state of the second plateau on its hysteresis loop is a vortex state; the chirality of the multi-nano-ring magnetic structures with overlapping ring edges and ring edges in contact connection is controllable. The present invention provides a method for regulating the chirality of magnetic nano-rings, and provides a new means for artificial magnetic nano-structure storage.

A method for nuclear magnetization reversal includes transforming a first magnetic skyrmion into a skyrmion texture by applying a first alternating current (AC) magnetic field to the first magnetic skyrmion, and then transforming the skyrmion texture into a second magnetic skyrmion by applying a second AC magnetic field to the skyrmion texture. The first magnetic skyrmion may be formed on a hemispherical shell, and the hemispherical shell may be formed by: (i) preparing a film having a plurality of protrusions, and (ii) stacking a first layer including at least one of platinum (Pt), nickel (Ni), or palladium (Pd) and a second layer including a ferromagnetic material on the film. The first AC magnetic field and the second AC magnetic field may have different frequencies.

This invention provides an orbital moment magnetic memory and its fabrication method. The orbital moment magnetic memory includes, from bottom to top, a substrate, an orbital Hall layer, a free layer, a barrier layer, and a fixing layer. The orbital Hall layer includes a metal layer and an FeMn layer arranged vertically. The free layer includes a first Co2Fe6B2 layer and an Fe3GaTe2 layer arranged vertically. The fixing layer includes a [Co / Pt] layer arranged vertically. n The structure consists of a first layer, a Ta layer, and a second Co2Fe6B2 layer. This structure utilizes the orbital Hall layer to efficiently generate orbital current, exchange bias field, and stray field, and leverages the strong spin-orbit coupling characteristics of the Fe3GaTe2 layer to achieve spin polarization and magnetization reversal at low current. This orbital-moment magnetic memory not only maintains a fast write speed while reducing power consumption, but also exhibits superior performance in high-speed data access, providing fundamental support for future applications in orbital electronics, magnetic storage, and other fields.

The invention discloses a magnetic storage array and a read-write method, in the magnetic storage array, a plurality of magnetic storage devices are arranged along an X-Y plane, and each word line simultaneously wraps the outer sides of a plurality of gates; each bit line is connected with the tops of the plurality of column electrodes; drain electrodes of the plurality of CMOS transistors are connected with the bottom of the column electrode; the grid line is connected with grid electrodes of the plurality of CMOS transistors; the source line is connected with the source electrodes of the plurality of CMOS transistors; magnetization overturning of a magnetic free layer of the magnetic tunnel junction is completed through the combined action of a spin-orbit moment and a spin-transfer moment, the spin-orbit moment is provided by spin-polarized electrons, the polarization direction of the spin-polarized electrons is the circumferential direction, generated by current passing through a column electrode, and the spin-transfer moment is provided by injecting write current in the radial direction of the magnetic tunnel junction. The judgment of the resistance state of the magnetic tunnel junction in the magnetic storage array is completed by injecting read current along the radial direction of the magnetic tunnel junction.

The invention provides a magnetization state detection system and method for a hard magnetic material, and relates to the technical field of magnetization state detection. Identifying a target magnetic flux density area from the magnetic flux density distribution diagram, and positioning the output end of the local excitation probe to a physical feature point corresponding to the target magnetic flux density area on the to-be-detected surface of the hard magnetic material; applying a local reverse magnetic field to the physical feature points, and obtaining a local magnetization reversal curve at the physical feature points; extracting a characteristic parameter representing the coercive force of the physical characteristic point from the local magnetization inversion curve, and if the attenuation percentage of the characteristic parameter relative to the reference coercive force parameter exceeds a second preset threshold value, determining that the area where the physical characteristic point is located is a demagnetized area; and outputting a magnetization state detection map of the hard magnetic material based on the demagnetized region. According to the invention, the precise positioning of the demagnetization area can be realized when the magnetic domain structure of the hard magnetic material generates local irreversible change.

This spin current magnetization rotational element includes a first ferromagnetic metal layer for a magnetization direction to be changed, and a spin-orbit torque wiring extending in a second direction intersecting a first direction which is an orthogonal direction to a surface of the first ferromagnetic metal layer and configured to be joined to the first ferromagnetic metal layer, wherein the spin-orbit torque wiring has a structure in which a spin conduction layer joined to the first ferromagnetic metal layer and a spin generation layer joined to the spin conduction layer on a surface on a side opposite to the first ferromagnetic metal layer are laminated.

The present invention provides a magnetic memory device with a simple structure, excellent ease of operation, and compatibility with semiconductor manufacturing processes, while simultaneously achieving both magnetization reversal under zero magnetic field conditions and low critical current density. [Solution] The magnetic memory device 10 comprises a channel layer 11 that generates a spin current or orbital current when an electric current is supplied, and a magnetic layer 12 disposed on one side of the channel layer 11 and whose magnetization direction can be reversed by the spin current, wherein the channel layer 12 contains maxines (MXenes) having a composition ratio represented by the following formula (1). M n+1 X n ...(1) In equation (1) above, M represents a transition metal, X represents carbon or nitrogen, and n represents an integer of 1 or more.

The invention discloses a low-temperature annealing method for improving the interface spin injection efficiency of a two-dimensional magnetic material, and relates to the technical field of two-dimensional magnetic material preparation. The preparation method comprises the following steps: S1, constructing a Fe3GaTe2 / Pt heterostructure; and S2, carrying out annealing treatment on the Fe3GaTe2 / Pt heterostructure. According to the method, the Fe3GaTe2 / Pt heterojunction interface is optimized through ultrahigh vacuum annealing, so that the spin injection efficiency and the magnetization turnover rate are effectively improved; according to the method, the annealing temperature of 100 DEG C is adopted and is far lower than the temperature in the annealing process in the prior art, and the annealing process has the characteristics of simplicity in operation, easiness in implementation, low energy consumption and the like, and can be applied to the semiconductor industry; according to the method, the current-driven magnetization turnover rate in the Fe3GaTe2 / Pt heterostructure subjected to low-temperature ultrahigh vacuum annealing treatment exceeds 95%, deterministic turnover is achieved, and the current-driven magnetization turnover rate is improved by more than 6 times compared with that of a sample before annealing.

The present invention proposes a high-density memory based on vertical channel transistors and a preparation method thereof, comprising a 1T1M structure memory cell consisting of a vertical channel field effect transistor (FET) and a magnetic tunnel junction (MTJ); the vertical channel FET is a FET based on a surround gate GAA configuration; the vertical channel FET effect transistor is stacked directly above the magnetic tunnel junction (MTJ); the memory cell uses the upper vertical channel FET transistor as a driving transistor, and the lower magnetic tunnel junction (MTJ) stores the memory cell state, and by controlling the current size and direction of the driving transistor, the magnetization reversal state of the free layer of the magnetic tunnel junction (MTJ) is regulated to realize data reading, erasing and writing; the present invention uses a surround gate (GAA) configuration vertical channel FET and a magnetic tunnel junction (MTJ) for vertical stacking, and its size can be miniaturized to 4F 2 , which can achieve MRAM with higher integration density.

A semiconductor storage apparatus according to one embodiment of the present disclosure includes a plurality of memory cells and a control circuit. Each of the memory cells includes a magnetization reversal memory device and a first switch device that controls a current to flow to the magnetization reversal memory device. The control circuit performs a writing control based on an asymmetric property of a writing error rate curve line with respect to a writing voltage of the magnetization reversal memory device.

The present application provides a magnetic head and a magnetic recording and reproducing apparatus in which the deterioration of a spin torque control element can be easily known. The magnetic head according to an embodiment includes a main pole, an auxiliary pole disposed apart from the main pole by a write gap, a spin torque control element disposed in the write gap, a bias current control section that supplies a bias current to the spin torque control element, and a resistance measurement section that measures a resistance value of the spin torque control element, wherein the difference between a first resistance value when the bias current is supplied with a polarity opposite to the polarity of the magnetization reversal of the spin torque control element and a second resistance value when the bias current is supplied with the polarity of the magnetization reversal of the spin torque control element is 4% or less.