40 results about "Spontaneous magnetization" patented technology

A magnetoresistance device is provided for improving thermal stability of a magnetoresistance element by preventing interdiffusion between a conductor (such as a via and an interconnection) for connecting the magnetoresistance element to another element and layers constituting the magnetoresistance element. A magnetoresistance device is composed of a magnetoresistance element, a non-magnetic conductor providing electrical connection between said magnetoresistance element to another element, and a diffusion barrier structure disposed between said conductor and said magnetoresistance element, the magnetoresistance element including a free ferromagnetic layer having reversible spontaneous magnetization, a fixed ferromagnetic layer having fixed spontaneous magnetization, and a tunnel dielectric layer disposed between said free and fixed ferroelectric layer.

A magneto-resistance device is composed of an anti-ferromagnetic layer (5), a pinned ferromagnetic layer (20), a tunnel insulating layer (9) and a free ferromagnetic layer (21). The pinned ferromagnetic layer (20) is connected to the anti-ferromagnetic layer (5) and has a fixed spontaneous magnetization. The tunnel insulating layer (9) is connected to the pinned ferromagnetic layer (20) and is non-magnetic. The free ferromagnetic layer (21) is connected to the tunnel insulating layer (9) and has a reversible free spontaneous magnetization. The pinned ferromagnetic layer (20) has a first composite magnetic layer (6) to prevent at lest one component of the anti-ferromagnetic layer (5) from diffusing into tunnel insulating layer (9).

An MRAM has a plurality of bit lines, a reference bit line, a plurality of memory cells and reference cells and a read section. The memory cells are provided along the bit lines and the reference cells along the reference bit line. The memory cell and reference cell have a tunneling magnetic resistance and a reference tunneling magnetic resistance, each of which has a spontaneous magnetization whose direction is reversed in accordance with data stored therein. The read section has a first resistance section which contains a ninth terminal connected with a bit line and a tenth terminal connected with the first power supply, a second resistance section which contains an eleventh terminal connected with the reference bit line and a twelfth terminal connected with the first power supply, and a comparing section which compares a sense voltage on the ninth terminal and a reference voltage of the eleventh terminal.

A technique is provided in which an offset magnetic field of a memory cell of a MRAM is reduced more effectively. The MRAM of the present invention is composed of a free layer (11) which has a reversible free spontaneous magnetization, a fixed layer (6) which has fixed spontaneous magnetization, and a spacer layer (10) formed of non-magnetic interposed between the free layer (11) and the fixed layer (6). The fixed layer (6) is formed such that orange peel effect and magneto-static coupling effect does not substantially influence on the free layer (11).

A magnetoresistance device is provided for improving thermal stability of a magnetoresistance element by preventing inter-diffusion between a conductor (such as a via and an interconnection) for connecting the magnetoresistance element to another element and layers constituting the magnetoresistance element. A magnetoresistance device is composed of a magnetoresistance element, a non-magnetic conductor providing electrical connection between said magnetoresistance element to another element, and a diffusion barrier structure disposed between the conductor and said magnetoresistance element, the magnetoresistance element including a free ferromagnetic layer having reversible spontaneous magnetization, a fixed ferromagnetic layer having fixed spontaneous magnetization, and a tunnel dielectric layer disposed between said free and fixed ferroelectric layer.

In accordance with the present invention, ferromagnetic thin films of iron that have reduced relaxation rates and methods of making the same are provided. It should be noted that pure iron is a ferromagnet (i.e., has a spontaneous magnetization alignment) with the lowest intrinsic damping rate of all of the ferromagnets. The present invention provides a ferromagnetic structure comprising a substrate and a ferromagnetic thin film of iron (Fe) formed on the substrate. An element selected from the group consisting of titanium (Ti), vanadium (V), chromium (Cr), and manganese (Mn) (i.e., a lower-Z transition metal element) is alloyed with the ferromagnetic thin film of iron to reduce the relaxation rate of the ferromagnetic thin film.

A shim adapted for altering a magnetic field of a magnet includes a first material which exhibits an increase in spontaneous magnetization with an increase in temperature for a predetermined temperature range.

The invention discloses a substrate integrated waveguide (SIW) H-plane self-bias isolator based on a soft magnetic nano wire array, which relates to a microwave device. The substrate integrated waveguide (SIW) H-plane self-bias isolator based on the soft magnetic nano wire array comprises an SIW transmission line and four orderly soft magnetic nano wire array bars arranged inside the transmission line, wherein the SIW transmission line comprises a dielectric substrate; the dielectric constant of the dielectric substrate material is between 8 and 16; metal layers are arranged on the upper surface and the lower surface of the dielectric substrate respectively; two rows of parallel conductive through holes arranged in the dielectric substrate form two through hole edges of the waveguide; each orderly soft magnetic nano wire array bar is long strip-shaped and is arranged between the substrate and the surface metal layer and attached to the metal layers on the upper surface and the lower surface, the long edge of the orderly soft magnetic nano wire array bar is parallel to the two through hole edges of the waveguide, spontaneous magnetization directions of two orderly soft magnetic nano wire array bars close to one side of the waveguide are upward, and spontaneous magnetization directions of two orderly soft magnetic nano wire array bars close to the other side of the waveguide are downward. The substrate integrated waveguide (SIW) H-plane self-bias isolator based on soft magnetic nano wire array is small in size, simple in structure, simple in processing and is easily integrated with a planar microwave circuit.

A carrier for developing an electrostatic latent image, including a particulate core material having a magnetism having developed spontaneous magnetization; and a covering layer comprising an electroconductive material, covering the surface of the particulate core material, wherein the carrier has an electrical resistivity Log R [Ωcm] of from 8.0 to 12.0 when measured by a method, including filling the carrier in a cell containing a pair of facing electrodes, each having a surface area of 2×4 [cm2] with a gap of 2 [mm] therebetween; and applying a DC voltage of 1,000 [V] therebetween to measure a DC resistivity, and a weight-average particle diameter (Dw) of from 25 to 45

A three-dimensional planar magnetic sensor comprises a first magnetic sensor, a second magnetic sensor, a third magnetic sensor and a circuit. The first magnetic sensor, the second magnetic sensor and the third magnetic sensor are arrange on the same plane and respectively measure component of a magnetic field in the first, second and third directions, and the third direction is perpendicular to the first direction and the second direction. The third magnetic sensor comprises a third fixed layer, a third magnetic insulation layer and a third free layer, wherein the magnetization direction of the third fixed layer is the third direction or the reverse direction, the spontaneous magnetization of the third free layer is the first direction and the second direction or inclines to the third direction by 0-180 degrees, the magnetic resistance value is an intermediate value in the spontaneous magnetization direction and changes along with the magnetic field. The three-dimensional planar magnetic sensor is manufactured by the semiconductor processing technology without vertical binding, output and durability are improved, and cost and time are saved.

A magnetic random access memory is composed of a plurality of first signal lines provided to extend in a first direction, a plurality of second signal lines provided to extend in a second direction substantially perpendicular to the first direction, a plurality of memory cells respectively provided at the intersections of the plurality of first signal lines and the plurality of second signal lines, and a plurality of magnetic structures respectively provided to the plurality of memory cells. Each of the plurality of memory cells has a magneto-resistance element containing a spontaneous magnetization layer which has a first threshold function, and the direction of the spontaneous magnetization of the spontaneous magnetization layer is reversed when an element applied magnetic field having the intensity equal to or larger than a first threshold function value is applied. Each of the plurality of magnetic structures has a second threshold function, and generates a magnetic structure magnetic field in response to a structure-applied magnetic field. When the structure-applied magnetic field has the intensity equal to or larger than the second threshold function value, a third magnetic field is generated as the magnetic structure magnetic field. When the structure applied magnetic field has the intensity less than the second threshold function value, a fourth magnetic field is generated which is weaker than the third magnetic field as the magnetic structure magnetic field. A first write current supplied to one of the plurality of first signal lines as a first selected signal line, and a first magnetic field is generated. A second write current is supplied to one of the plurality of second signal lines as a second selected signal line, and a second magnetic field is generated. A first synthetic magnetic field of the first magnetic field and the second magnetic field is applied to the magnetic structure as the structure applied magnetic field. The element applied magnetic field having the intensity equal to or larger than the first threshold function value is applied to the selected memory cell provided at the intersection of the first selected signal line and the second selected signal line. A second synthetic magnetic field of the first synthetic magnetic field and the magnetic structure magnetic field is generated as the element applied magnetic field such that the element applied magnetic field having the intensity less than the first threshold function value is applied to each of non-selected memory cells other than the selected memory cell.

The invention discloses a magnetic temperature sensitive material of manganese doped terbium iron oxide and a preparation method of monocrystal and polycrystal of the magnetic temperature sensitive material. Tb4O7, MnO2 and Fe2O3 powder are synthesized into a TbFe1-xMnxO3 polycrystalline material by using a solid reaction process, and the polycrystalline material grows into a monocrystal material by using an optical floating zone furnace method. According to the magnetic temperature sensitive material, an external magnetic field is not needed, the magnetic transition temperature sensitivity is high, the magnetic transition critical temperature can be adjusted and can reach the room temperature, and the magnetic temperature sensitive material is applied to magnetic temperature sensitive devices. According to the magnetic temperature sensitive material, different materials of which the magnetic transition critical temperature is between -264.65 DEG C and 25.85 DEG C can be obtained by changing the proportion, the magnetic transition speed is higher than the traditional magnetic transition speed near the Curie temperature due to the phase change, spontaneous magnetization occurs at more than critical temperature, and therefore, the external magnetic field is not needed to induce before and after transition. The material is better than a traditional magnetic sensitive temperature device material depending on the magnetic transition near the Curie temperature.

The invention relates to a magnetic measurement method, in particular to a method for testing a hard and easy magnetization direction of a magnetic film material with exchange bias. The method comprises the following steps of: arranging a sample film to be tested in an external direct current magnetic field, so that a plane of the sample film to be tested is parallel to the direction of the external magnetic field; rotating the sample film to be tested around an axis vertical to the plane; during test, optionally applying a given external magnetic field, keeping the magnetic field invariable, and recording an initial position of the sample and magnetization at the moment; rotating the sample film to be tested at an angle, and measuring a corresponding projection value M of spontaneous magnetization MS of the film to be tested in the direction of the external magnetic field at the angle theta0 so as to obtain a function of the sample film to be tested at different rotating angles theta0 and corresponding M values; and determining an easy magnetization axis or a hard magnetization axis of the exchange bias film according to a measured M-theta0 curve.

A substrate-integrated waveguide H-plane self-bias isolator of a soft magnetic nanowire array relates to a microwave device. The invention includes a SIW transmission line and four ordered soft magnetic nanowire array strips placed in the transmission line. The SIW transmission line includes a dielectric substrate. The dielectric constant of the dielectric substrate material is between 8-16, the upper surface and the lower surface of the dielectric substrate are respectively provided with metal layers, and two rows of parallel conductive through holes arranged in the dielectric substrate form the two through hole sides of the waveguide. ; The ordered soft magnetic nanowire array strip is strip-shaped, arranged between the substrate and the surface metal layer, and attached to the upper and lower surface metal layers, the long side of the ordered soft magnetic nanowire array strip and the two channels of the waveguide The hole sides are parallel, the spontaneous magnetization direction of the two ordered soft magnetic nanowire array strips near the waveguide side is upward, and the spontaneous magnetization direction of the two ordered soft magnetic nanowire array strips near the other side of the waveguide is downward. The invention has the advantages of small volume, simple structure, easy processing and easy integration with planar microwave circuits.

The invention discloses a test technique of magnetic material, which is characterized by the following: placing the detected sample film in the extra DC magnetic field; paralleling the detected sample film plane to the extra magnetic field direction; rotating the detected sample film around the vertical axle of plane; making the detected film reach magnet saturation and extra magnet field between saturated field and coercive field; keeping the magnet field; rotating the detected sample at certain angle; measuring the spontaneous magnetization strength MS and corresponding projection value M in the theta0 condition; calculating the M value function corresponding to different theta0.