Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Hiro

204 results about "Magnetization reversal" patented technology

Magnetization reversal, or switching, represents the process that leads to a 180° reorientation of the magnetization vector with respect to its initial direction, from one stable orientation to the opposite one. Technologically, this is one of the most important processes in magnetism that is linked to the magnetic data storage process such as currently used in hard disk drives [1]. As it is known today, there are only a few possible ways to reverse the magnetization of a metallic magnet: magnetization reversal in an applied magnetic field magnetization reversal by spin injection magnetization reversal by circularly polarized light

Three-terminal magnetostatically coupled spin transfer-based MRAM cell

A magnetic memory device for reading and writing a data state comprises at least three terminals including first, second, and third terminals. The magnetic memory device also includes a spin transfer (ST) driven element, disposed between the first terminal and the second terminal, and a readout element, disposed between the second terminal and the third terminal. The ST driven element includes a first free layer, and a readout element includes a second free layer. A magnetization direction of the second free layer in the readout element indicates a data state. A magnetization reversal of the first free layer within the ST driven element magnetostatically causes a magnetization reversal of the second free layer in the readout element, thereby recording the data state.
Owner:SAMSUNG SEMICON

Hexagonal ferrite magnetic particles, magnetic recording powder, and magnetic recording medium

Hexagonal ferrite magnetic particles have an activation volume ranging from 1,000 nm3 to 1,500 nm3, and ΔE10% / kT, thermal stability at 10% magnetization reversal, is equal to or greater than 40.
Owner:FUJIFILM CORP

High output nonvolatile magnetic memory

A magnetic memory is provided with a high-output memory cell capable of switching and magnetization reversal operations by means of two terminals. There is formed an MIS junction laminated layer comprising a diode, a spin transfer torque magnetization reversal induction layer, and a tunnel magnetoresistive device. A bit line and a word line are connected to the laminated layer.
Owner:HITACHI LTD

Spin injection device, magnetic device using the same, magnetic thin film used in the same

A spin injection device capable of spin injection magnetization reversal at low current density, a magnetic apparatus using the same, and magnetic thin film using the same, whereby the spin injection device (14) including a spin injection part (1) comprising a spin polarization part (9) including a ferromagnetic fixed layer (26) and an injection junction part (7) of nonmagnetic layer, and a ferromagnetic free layer (27) provided in contact with the spin injection part (1) is such that in which the nonmagnetic layer (7) is made of either an insulator (12) or a conductor (25), a nonmagnetic layer (28) is provided on the surface of the ferromagnetic free layer (27), electric current is flown in the direction perpendicular to the film surface of the spin injection device (14), and the magnetization of the ferromagnetic free layer (27) is reversed. This is applicable to such various magnetic apparatuses and magnetic memory devices as super gigabit large capacity, high speed, non-volatile MRAM and the like.
Owner:JAPAN SCI & TECH CORP

Spin-injection magnetoresistance effect element

The present invention provides a spin-injection magnetoresistance effect element that can avoid use of a large writing current and allows use of a large reading current. The spin-injection magnetoresistance effect element includes (A) a magnetization reversal layer that has a first face and a second face and stores information, (B) a first magnetization reference layer that is disposed near one end of the magnetization reversal layer with the intermediary of a first nonmagnetic film between the layers, and is magnetized in a first direction, (C) a second magnetization reference layer that is disposed near the other end of the magnetization reversal layer with the intermediary of a second nonmagnetic film between the layers, and is magnetized in a second direction that is the opposite direction of the first direction, (D) a first electrode that is electrically coupled to the first magnetization reference layer, (E) a second electrode that is electrically coupled to the second magnetization reference layer, and (F) a third electrode that is disposed in a manner of facing the second face of the magnetization reversal layer with an insulating film between the third electrode and the magnetization reversal layer.
Owner:SONY CORP

Nonvolatile sram/latch circuit using current-induced magnetization reversal mtj

The present invention is a memory circuit that includes a bistable circuit that stores data, and a ferromagnetic tunnel junction device that nonvolatilely stores the data in the bistable circuit according to a magnetization direction of a ferromagnetic electrode free layer, the data nonvolatilely stored in the ferromagnetic tunnel junction device being able to be restored in the bistable circuit. According to the present invention, writing data to and reading data from the bistable circuit can be performed at high speed. In addition, even though a power source is shut down, it is possible to restore data nonvolatilely stored in the ferromagnetic tunnel junction devices to the bistable circuit.
Owner:JAPAN SCI & TECH CORP

Magnetic memory

A magnetic memory includes: a base layer; a magnetization free layer; a barrier layer; and a magnetization reference layer. The magnetization free layer, with which the base layer is covered, has invertible magnetization and is magnetized approximately uniformly. The barrier layer, with which the magnetization free layer is covered, is composed of material different from material of the base layer. The magnetization reference layer is arranged on the barrier layer and has a fixed magnetization. When the magnetization of the magnetization free layer is inverted, a first writing current is made to flow from one end to the other end of the magnetization free layer in an in-plane direction without through the magnetization reference layer.
Owner:RENESAS ELECTRONICS CORP

Voltage-controlled magnetization reversal writing type magnetic random access memory device and method of writing and reading information using the same

A voltage-controlled magnetization reversal writing type Magnetic Random Access Memory (MRAM) device. The MRAM device includes electrically conductive base electrodes, a piezoelectric layer, an insulation layer, a free ferromagnetic layer, a nonmagnetic layer, a pinned ferromagnetic layer, an antiferromagnetic layer and two electrically conductive reading lines. The electrically conductive base electrodes are provided with two writing lines having positive and negative electrodes. The left and right surfaces of piezoelectric layer are disposed to abut the writing lines of the electrically conductive base electrodes, respectively. The insulation layer is disposed beneath the piezoelectric layer and is formed to separate the positive and negative electrodes. The free ferromagnetic layer is disposed on the insulation layer. The nonmagnetic layer is disposed on the free ferromagnetic layer. The pinned ferromagnetic layer is disposed on the nonmagnetic layer. The antiferromagnetic layer is disposed on the pinned ferromagnetic layer. The two electrically conductive reading lines are formed to be perpendicular to each other.
Owner:KOREA ADVANCED INST OF SCI & TECH

Nonvolatile latch circuit

A nonvolatile latch circuit includes: first and second inverters cross-coupled to hold 1-bit data; first and second magnetoresistive elements each having first to third terminals; and a current supply circuitry configured to supply a magnetization reversal current for changing the magnetization states of the first and second maqnetoresistive elements in response to the 1-bit data. The power terminal of the first inverter is connected to the first terminal of the first magnetoresistive element and the power terminal of the second inverter is connected to the first terminal of the second magnetoresistive element. The current supply circuitry is configured to supply the magnetization reversal current to the second terminals of the first and second magnetoresistive elements. The third terminal of the first magnetoresistive element is electrically connected to the third terminal of the second magnetoresistive element.
Owner:NEC CORP

Solid-state component based on current-induced magnetization reversal

A solid-state component including a network of multi-layer structures is described. Each multi-layer structure exhibits magnetoresistance and has magnetization vectors associated therewith which are operable to be switched at least in part by current-induced magnetization reversal. The solid-state component generates an output signal when the network of multi-layer structures is resistively imbalanced. The output signal corresponds to output nodes in the network and is a function of an input signal applied at input nodes in the network.
Owner:INTEGRATED MAGNETOELECTRONICS CO

Nonvolatile memory device

ActiveUS20070268737A1Improved thermal disturbance resistanceImprove access speedDigital storageThreshold currentElectrical current
Between the value of an electric current and the supply duration for which the electric current is supplied that cause magnetization reversal, there is the relation of monotonous decrease. This means that, as the supply duration is shortened, the threshold current value for causing the magnetization reversal is larger. Therefore, in terms of suppressing occurrence of read disturb, the read current supply duration may be shortened to increase the threshold value of the current causing the magnetization reversal and thereby ensure a sufficient read disturb margin. Therefore, the read current supply duration may be shortened relative to the write current supply duration ensure the read disturb margin and suppress occurrence of read disturb.
Owner:RENESAS ELECTRONICS CORP

Perpendicular magnetic recording head and method of manufacturing the same

A concave portion is formed on the end surface of a main magnet pole layer on the trailing side. A convex portion is formed on the end surface of a return yoke layer on the leading side, which opposes the concave portion formed on the end surface of the main magnet pole layer on the trailing side, and the distance (gap length) between the main magnet pole layer and the return yoke layer in the direction of the film thickness is constant. Consequently, the magnetic field generating from the main magnet pole layer toward the recording medium is appropriately prevented from isotropically spreading in the trailing direction, and the width of magnetization reversal between the recording patterns, which are magnetized reversely from each other, can be reduced over the entire area.
Owner:TDK CORPARATION

Magnetoresistive effect element and magnetic memory

It is possible to provide a magnetoresistive effect element and a magnetic storage which has thermal stability even if it is made fine and in which the magnetization in the magnetic recording layer can be inverted at a low current density. A magnetoresistive effect element includes: a magnetization pinned layer having a magnetization pinned in a direction; a magnetization free layer of which magnetization direction is changeable; a tunnel barrier layer provided between the magnetization pinned layer and the magnetization free layer; a first antiferromagnetic layer provided on the opposite side of the magnetization pinned layer from the tunnel barrier layer; and a second antiferromagnetic layer which is provided on the opposite side of the magnetization free layer from the tunnel barrier layer and which is thinner in thickness than the first antiferromagnetic layer, wherein the direction of the magnetization of the free magnetization layer can be converted by pouring an electron whose polarity is changed in spin polarization into the free magnetization layer.
Owner:KK TOSHIBA

Magnetic memory

A magnetoresistance effect element is also located between second wiring and common wiring. The magnetoresistance effect element is electrically connected to the second wiring without a spin filter. When a reading current is supplied between the second wiring for supplying a reading current and the common wiring, since this is not supplied via a spin filter, no spin polarized current is supplied into the magnetoresistance effect element, so that it becomes difficult to magnetization-reverse a magnetosensitive layer. Even in a structure where, in order to improve recording density, the magnetosensitive layer is reduced in area so as to lower a writing current, no magnetization reversal occurs due to a supply of the reading current, and information can be read out without making the reading current considerably small in comparison with the writing current.
Owner:TDK CORPARATION

Magnetic recording media and method of forming them

InactiveUS7097924B2Steep distribution of a recording magnetic fieldRecording magnetic field from a single magnetic polar head is increasedConstruction of head windingsBase layers for recording layersHigh densityRecording media
The present invention is directed to-carrying out a high density magnetic recording to a material having a large coercive force by perpendicular magnetic recording head.By giving a patterning onto a soft magnetic under layer of a perpendicular two-layer recording media in sync with a period of a recording bit, a magnetic field from a write head can be allowed to converge to a soft magnetic column. Therefore, a magnetization reversal of the magnetic recording media material having a large anisotropic constant becomes possible, and then a high density magnetic recording can be achieved.
Owner:HITACHI LTD

Semiconductor memory device and manufacturing method for semiconductor memory device

A channel layer is deposited on a first impurity layer, a second impurity layer is deposited on the channel layer, a gate electrode is placed to surround a circumference of the channel layer with a gate insulating film interposed therebetween, a spin-injection magnetization-reversal element is deposited on the second impurity layer, a bit line is placed on the spin-injection magnetization-reversal element, and a word line is placed on the bit line to be electrically connected to the gate electrode.
Owner:KIOXIA CORP

Perpendicular magnetic recording medium and magnetic recording/reproducing apparatus using the same

Embodiments of the present invention help allow accurate control of the magnetization reversal in a magnetic recording layer in small reversal units, whereby high-density recording can be achieved. According to one embodiment, by forming an intermediate layer having a granular structure similar to that of the magnetic recording layer below the magnetic recording layer, a continuous crystal grain boundary is formed at the interface between the magnetic recording layer and the intermediate layer, thereby preventing incomplete formation of the crystal grain boundary found in the initial growth layer of the magnetic recording layer. The intermediate layer comprises a non-magnetic alloy comprising Co and Cr as its main components and an oxide such as Al, Cr, Hf. Mg, Nb, Si, Ta, Ti and Zr. Further, the average content of the oxygen element in the intermediate layer is in the range from 6 at % to 20 at %.
Owner:WESTERN DIGITAL TECH INC

Multi-valued data recording spin injection maganetization reversal element and device using the element

A spin injection magnetization reversal device is disclosed which inhibits an increase in resistance to enable multi-valued data recording. A ferromagnetic fixed layer and n groups each including a ferromagnetic free layer and an isolation layer are disclosed. The groups are disposed from the group including the first ferromagnetic free layer provided on the ferromagnetic fixed layer to the group including the n-th ferromagnetic free layer in the order. Each of the ferromagnetic free layers is preferably formed of one of a CoCrPt alloy, a CoCr alloy and a CoPt alloy with Pt or Cu concentration therein made monotonically decreased from the concentration in the first ferromagnetic free layer to that in the n-th ferromagnetic free layer.
Owner:FUJI ELECTRIC CO LTD

Perpendicular magnetic recording system and write head with transverse auxiliary pole for fast switching of write pole magnetization

A perpendicular magnetic recording system has a write head having a main coil (the write coil) and main pole (the write pole) that directs write flux in a direction perpendicular to the recording layer in the magnetic recording medium, and a transverse auxiliary pole (TAP) that injects auxiliary magnetic flux into the write pole at an angle to the primary or perpendicular axis of the write pole. The additional flux from the TAP, which is injected non-parallel to the primary magnetization of the write pole, exerts a torque on the magnetization of the write pole, thereby facilitating magnetization reversal of the write pole. The TAP is coupled to the main coil but not electrically connected to it. A separate passive coil, not electrically connected to the main coil, may be wrapped as a loop around the main pole and the TAP. Alternatively, the TAP may be located near one of the electrically conductive turns of the main coil.
Owner:WESTERN DIGITAL TECH INC

Method and apparatus of using magnetic material with residual magnetization in transient electromagnetic measurement

A transmitter antenna assembly for transient electromagnetic well logging instrument comprises an antenna coil coupled with a current source and a magnetic core having residual magnetization. Switching current in the antenna coil results in magnetization reversal in the magnetic core and change in magnetic dipole moment of the antenna. After the magnetization reversal is complete the current is removed and the new vector of magnetic dipole of the antenna maintains constant (steady-state phase of the antenna dipole) due to magnetic hysteresis of magnetic material employed for the magnetic core. No power expenditure during the steady-state phase of the magnetic dipole facilitates highly effective generation and fast switching of a large magnetic dipole. The magnetic core also serves as a shield between the antenna coil and any conductive part of the antenna assembly. Embodiments suitable for measurement-while-drilling or measurements through casing make use of residual magnetization of magnetic drill collar or magnetic casing respectively.
Owner:BAKER HUGHES INC

Magnetic recording apparatus using magnetization reversal by spin injection with thermal assistance

The present invention provides a high density magnetic recording apparatus capable of performing a magnetic write to a magnetic memory cell therein by directly applying current into the memory cell without using external magnetic field; and performing a record read from the cell structure. To reduce the current density required for magnetization reversal by spin injection, the magnetic recording medium is irradiated with laser light so as to heat a magnetic memory cell to a temperature higher than the room temperature but lower than the Curie temperature. While the coercivity of the magnetic recording medium is effectively lowered, magnetic write operation is performed by applying external current into the magnetic memory cell.
Owner:HITACHI LTD

Perpendicular magnetic recording system with auxiliary coil and circuitry for fast switching of write pole magnetization

A perpendicular magnetic recording system has a write head having a main coil (the write coil) and main pole (the write pole) that directs write flux in a direction perpendicular to the recording layer in the magnetic recording medium, and an auxiliary coil and auxiliary pole that injects magnetic flux into the write pole at an angle to the primary or perpendicular axis of the write pole. The additional flux from the auxiliary pole, which is injected non-parallel to the primary magnetization of the write pole, exerts a relatively large torque on the magnetization of the write pole, thereby facilitating magnetization reversal of the write pole. Electrical circuitry is connected to the main coil and the auxiliary coil to generate the auxiliary flux simultaneous with the switching of the magnetization of the write pole.
Owner:WESTERN DIGITAL TECH INC

Magnetic memory and method for driving the same, and magnetic memory device using the same

A magnetic memory of the present invention includes two or more memory layers and two or more tunnel layers that are stacked in the thickness direction of the layers. The two or more memory layers are connected electrically in series. A group of first layers includes at least one layer selected from the two or more memory layers. A group of second layers includes at least one layer selected from the two or more memory layers. A resistance change caused by magnetization reversal in the group of first layers differs from a resistance change caused by magnetization reversal in the group of second layers.
Owner:PANASONIC CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products