1518 results about "Magneto resistance" patented technology

A read sensor for a read transducer is fabricated. The read transducer has field and device regions. A read sensor stack is deposited. A mask covering part of the stack corresponding to the read sensor is provided. The read sensor having inboard and outboard junction angles is defined from the stack in a track width direction. A critical junction (CJ) focused ion beam scan (FIBS) polishing that removes part of the read sensor based on the junction angles is performed. A hard bias structure is deposited and the transducer planarized. A remaining portion of the mask is removed. A stripe height mask covering part of the read sensor and hard bias structure in a stripe height direction is provided. The read sensor stripe height is defined. A tunneling magnetoresistance (TMR) FIBS polishing that removes part of the stack in the field region is performed. An insulating layer is provided.

It is possible to reduce a current required for spin injection writing. A magneto-resistance effect element includes: a first magnetization pinned layer; a magnetization free layer; a tunnel barrier layer; a second magnetization pinned layer whose direction of magnetization is pinned to be substantially anti-parallel to the direction of magnetization of the first magnetization pinned layer, and; a non-magnetic layer. When the second magnetization pinned layer is made of ferromagnetic material including Co, material for the non-magnetic layer is metal including at least one element selected from the group consisting of Zr, Hf, Rh, Ag, and Au; when the second magnetization pinned layer is made of ferromagnetic material including Fe, material for the non-magnetic layer is metal including at least one element selected from the group consisting of Rh, Pt, Ir, Al, Ag, and Au; and when the second magnetization pinned layer is made of ferromagnetic material including Ni, material for the non-magnetic layer is metal including at least one element selected from the group consisting of Zr, Hf, Au, and Ag.

A magnetic tunnel element that can be used, for example, as part of a read head or a magnetic memory cell, includes a first layer formed from an amorphous material, an amorphous tunnel barrier layer, and an interface layer between the first layer and the tunnel barrier layer. The interface layer is formed from a material that is crystalline when the material is in isolation from both the first layer and the tunnel barrier layer. Alternatively, the thickness of the interface layer is selected so that the interface layer is not crystalline. The first layer is formed from at least one material selected from the group consisting of amorphous ferromagnetic material, amorphous ferrimagnetic materials, and amorphous non-magnetic materials. The interface layer is formed from a material selected from the group consisting of a ferromagnetic material and a ferrimagnetic material.

A foundation layer increasing adhesive properties to a substrate, another foundation layer controlling orientation of an antiferromagnetic layer, the antiferromagnetic layer including a disordered alloy of IrMn, a pinning layer, and a cap protection layer are formed in the order on the substrate. The pinning layer includes two layers having an exchange coupling giving layer which exchange-couples to the antiferromagnetic layer and an exchange coupling enhancement layer which enhances the exchange coupling, the exchange coupling giving layer is made of a ferromagnetic material including Co or a Co100-XFeX alloy (O<=X<25) having face-centered cubic structure. The exchange coupling enhancement layer is made of Fe or a Co100-YFeY alloy (25<=Y<=100) having body-centered cubic structure.

The present invention is directed to align crystal c-axes in magnetic layers near two opposed junction wall faces of a magnetoresistive element so as to be almost perpendicular to the junction wall faces. A magnetic sensor stack body has, on a substrate, a magnetoresistive element whose electric resistance fluctuates when a bias magnetic field is applied and, on sides of opposed junction wall faces of the magnetoresistive element, field regions including magnetic layers for applying the bias magnetic field to the element. The magnetoresistive element has at least a ferromagnetic stack on a part of an antiferromagnetic layer, and width of an uppermost face of the ferromagnetic stack along a direction in which the junction wall faces are opposed to each other is smaller than width of an uppermost face of the antiferromagnetic layer in the same direction.

In a magnetic random access memory, a cross point cell array of memory cells is arranged in a matrix of columns and rows, and each of the memory cells has a magneto-resistance element. A column of dummy memory cells is provided, and each of the dummy memory cells has a magneto-resistance element. Word lines are provided for the rows of the memory cells and the dummy memory cells, respectively, and bit lines are provided for the columns of the memory cells, respectively. A dummy bit line is provided for the column of dummy memory cells. A read circuit is connected with the cross point cell array and the dummy bit line.

A magnetoresistive element includes a first reference layer having magnetic anisotropy perpendicular to a film surface, and an invariable magnetization, a recording layer having a stacked structure formed by alternately stacking magnetic layers and nonmagnetic layers, magnetic anisotropy perpendicular to a film surface, and a variable magnetization, and an intermediate layer provided between the first reference layer and the recording layer, and containing a nonmagnetic material. The magnetic layers include a first magnetic layer being in contact with the intermediate layer and a second magnetic layer being not in contact with the intermediate layer. The first magnetic layer contains an alloy containing cobalt (Co) and iron (Fe), and has a film thickness larger than that of the second magnetic layer.

A magnetoresistive random-access memory device with a magnetic tunnel junction stack having a significantly improved performance of the free layer in the magnetic tunnel junction structure. The memory device includes an antiferromagnetic structure and a magnetic tunnel junction structure disposed on the antiferromagnetic structure. The magnetic tunnel junction structure includes a reference layer and a free layer with a barrier layer sandwiched therebetween. Furthermore, a capping layer including a tantalum nitride film is disposed on the free layer of the magnetic tunnel junction structure.

An MR element includes an MR stack disposed between first and second main shield portions, and a pair of side shields disposed on opposite sides of the MR stack in the track width direction. The first main shield portion includes a first exchange coupling shield layer that is exchange-coupled to a first antiferromagnetic layer. The second main shield portion includes a second exchange coupling shield layer that is exchange-coupled to a second antiferromagnetic layer. The MR stack includes a spacer layer, and first and second free layers with the spacer layer therebetween. The direction of magnetization of the first free layer is controlled by the first exchange coupling shield layer. The direction of magnetization of the second free layer is controlled by the second exchange coupling shield layer. Each side shield includes at least one shield-coupling magnetic layer that is in contact with and magnetically coupled to one of the first and second exchange coupling shield layers.

The arrangement for contactless determination of an angular position of a rotatable element, such as a camshaft of an internal combustion engine, which includes a magnet arranged to rotate with the rotatable element; a magnetic field sensor stationary in relation to the rotatable element and including a first sensor element (IC1) and a second sensor element (IC2), wherein the first sensor element generates a first output signal linearly dependent on an angle between the magnetic field and the magnetic field sensor according to a magnetoresistive effect, whereby the first output signal has respective values between 0° and 180° that repeat between 180° and 360°, and the second sensor element generates a second output signal having a high value between 0° and 180° and a low value between 180° and 360° according to a Hall effect; and an evaluation circuit (A) for analyzing output signals of both sensor elements to determine the angular position of the rotatable element between 0° and 360°. The evaluating circuit finds that the absolute angular position is either of two angular orientations spaced 180° from each other only from the signal from the first sensor element and selects one of them as the absolute angular position according to the second output signal.

A layered ferromagnetic structure is composed of a first ferromagnetic layer positioned over a substrate; a second ferromagnetic layer positioned over the first ferromagnetic layer; and a first non-magnetic layer placed between the first and second ferromagnetic layers. The top surface of the first ferromagnetic layer is in contact with the first non-magnetic layer. The first ferromagnetic layer includes a first orientation control buffer that exhibits an effect of enhancing crystalline orientation of a film formed thereon.

The magneto-resistance effect element includes: a first ferromagnetic layer serving as a magnetization fixed layer; a magnetization free layer including a second ferromagnetic layer provided on one side of the first ferromagnetic layer, a third ferromagnetic layer which is formed on an opposite side of the second ferromagnetic layer from the first ferromagnetic layer and has a film face having an area larger than that of the second ferromagnetic layer and whose magnetization direction is changeable by an external magnetic field, and an intermediate layer which is provided between the second ferromagnetic layer and the third ferromagnetic layer and which transmits a change of magnetization direction of the third ferromagnetic layer to the second ferromagnetic layer; and a tunnel barrier layer provided between the first ferromagnetic layer and the second ferromagnetic layer.

A magnetic tunnel junction (MTJ) for use in a magnetoresistive random access memory (MRAM) has a CoFeB alloy free layer located between the MgO tunnel barrier layer and an upper MgO capping layer, and a CoFeB alloy enhancement layer between the MgO capping layer and a Ta cap. The CoFeB alloy free layer has high Fe content to induce perpendicular magnetic anisotropy (PMA) at the interfaces with the MgO layers. To avoid creating unnecessary PMA in the enhancement layer due to its interface with the MgO capping layer, the enhancement layer has low Fe content. After all of the layers have been deposited on the substrate, the structure is annealed to crystallize the MgO. The CoFeB alloy enhancement layer inhibits diffusion of Ta from the Ta cap layer into the MgO capping layer and creates good crystallinity of the MgO by providing CoFeB at the MgO interface.

A wireless sensor network system using GMR magnetic sensitive technology to detect vehicle information of the invention consists of two GMR sensor detecting end machines and a wireless receiving end machine. The two GMR sensor detecting end machines are connected with the wireless receiving end machine. The detection method of the invention detects information such as vehicle speed, vehicle length, driving direction, vehicle flow, lane occupancy ratio, etc., according to change data of the surrounding ground magnetic field sensed by the GMR sensor when the vehicles pass. The wireless sensor network system is characterized in having high precision of detecting speed, adaptability to various roads, low cost, convenient maintenance and high anti-interference ability and causing small destroy to road surface, etc.

A 3-axis magnetic sensor includes a magnetoresistive element formed by a plurality of magnetoresistive element bars connected in series by a bias magnet. The magnetoresistive element of the X-axis sensor and the magnetoresistive element of the Y-axis sensor are formed on a plane parallel to the surface of the substrate. The magnetization sensitivity direction vertical to the longitudinal direction of each of the magnetoresistive element bars. The magnetization direction of the magnetoresistive element of the X-axis sensor orthogonally intersects that of the magnetoresistive element of the Y-axis sensor. Furthermore, the magnetoresistive element of the Z-axis sensor is formed on the inclined surface of the protrusion protruding from the surface of the substrate and its magnetization direction is in the inclined surface. The magnetization sensitivity direction of the Z-axis sensor is vertical to the longitudinal direction of the magnetoresistive element bar.

A magnetic memory is composed of: a magnetoresistance element including a free magnetic layer; a first interconnection extending in a first direction obliquely to an easy axis of the free magnetic layer; a second interconnection extending in a second direction substantially orthogonal to the first direction; and a write circuit writing data into the free magnetic layer through developing a first write current on the first interconnection, and then developing a second write current on the second interconnection with the first write current turned on. The free magnetic layer includes: first to N-th ferromagnetic layers and first to (N−1)-th non-magnetic layers with N being equal to or more than 4, the i-th non-magnetic layer being disposed between the i-th and (i+1)-th ferromagnetic layers with i being any of natural numbers equal to or less than N−1. The free magnetic layer is designed so that antiferromagnetic coupling(s) between the j-th and (j+1)-th ferromagnetic layers is stronger than that between the first and second ferromagnetic layers, j being any of integers ranging from 2 to N−2.

An area of an element can be made small and fluctuation in area can be reduced. A magneto-resistance effect element is provided with a first electrode with an end face; a magneto-resistance effect film which is formed such that a surface thereof comes in contact with the end face of the first electrode; and a second electrode which is formed on another surface of the magneto-resistance effect element opposed from the surface coming in contact with the surface of the first electrode. The magneto-resistance effect film includes a magnetization pinned layer whose magnetization direction is pinned, a magnetization free layer whose magnetization direction is changeable, and a first non-magnetic layer which is provided between the magnetization pinned layer and the magnetization free layer.

A magnetic sensor comprising a bridge circuit in which four magnetoresistive devices are connected, the magnetoresistive device comprising a spin-valve, giant-magnetoresistive film comprising a pinned layer having unidirectional magnetic anisotropy, a free layer whose magnetization direction is rotated in alignment with an external magnetic field direction, and an intermediate layer sandwiched by the pinned layer and the free layer, and at least one of the magnetoresistive devices meeting the condition of 36°≦θ<45°, wherein θ is an acute angle between its longitudinal direction and the magnetization direction of the pinned layer.

A magnetoresistive element is provided as a spin valve having a synthetic free layer. More specifically, the synthetic free layer includes a low perpendicular anisotropy layer that is separated from a high perpendicular anisotropy layer by a spacer. Thus, the high anisotropy material introduces an out-of-plane component by exchange coupling. The high perpendicular anisotropy material also has low spin polarization. Further, the low anisotropy material positioned closer to the pinned layer has a high spin polarization. As a result, the magnetization of the low anisotropy material is re-oriented from an in-plane direction to an out-of-plane direction. Accordingly, the overall free layer perpendicular anisotropy can be made small as a result of the low anisotropy material and the high anisotropy material. Adjusting the thickness of these layers, as well as the spacer therebetween, can further lower the anisotropy and thus further increase the sensitivity.