Patent application number | Description | Published |
20080238420 | MAGNETIC SENSOR - The magnetic sensor comprises a spin-valve GMR including a free layer having an elongated form as seen in a laminating direction and a permanent magnet layer having an elongated form as seen in the laminating direction. The permanent magnet layer is arranged in parallel with the free layer. | 10-02-2008 |
20080253033 | Thin-film magnetic head having electric lapping guide and method of making the same - A magnetic head in which the size of MR height is controlled precisely, a head gimbal assembly and a hard disk drive which are mounted with such a magnetic head, and a method of making a magnetic head in which the size of MR height is controlled precisely. | 10-16-2008 |
20080253037 | Thin-Film Magnetic Head and Manufacturing Method Thereof - A thin-film magnetic head includes a lower magnetic shield layer, an MR multi-layered structure formed on the lower magnetic shield layer so that current flows in a direction perpendicular to surfaces of laminated layers, an insulation layer formed to surround the MR multi-layered structure, an additional metal layer laminated on at least the MR multi-layered structure, an upper electrode layer made of a soft magnetic material laminated on the additional metal layer and the insulation layer, and an upper magnetic shield layer laminated on the upper electrode layer. The additional metal layer has a multi-layered structure including a nonmagnetic metal layer and a soft magnetic layer laminated on the nonmagnetic metal layer, and has a length along a track-width direction of the MR multi-layered structure larger than a width of a magnetization-free layer in the MR effect multi-layered structure. | 10-16-2008 |
20080282532 | Method of making thin film magnetic head using electric lapping guide - As a reticle pattern corresponding to a resist pattern for magnetic detection element layer and a reticle pattern corresponding to a resist pattern for conductive layer in a reticle, a reticle having a convex portion that projects in the height direction and a concave portion that dents in the direction opposite to the convex portion, respectively, is used to form a convex portion and concave portion corresponding to the convex portion and concave portion of the reticle pattern in the resist pattern for magnetic detection element and in the resist pattern for conductive layer, respectively. Then, with each resist pattern as a mask, unnecessary portions of the magnetic detection element layer and conductive layer are removed to determine an initial height of the magnetic detection element layer and an initial height perpendicular to a medium facing surface of the conductive layer, and to form a convex portion and concave portion corresponding to the convex portion and concave portion of the resist pattern in the magnetic detection element layer and in the conductive layer, respectively. Then, based on a ratio between a width in the track width direction of the convex portion of the magnetic detection element layer and a width in the track width direction of the concave portion of the magnetic detection element layer, a deviation in the height direction concerning a surface intersecting the height direction of the magnetic detection element layer is obtained, and based on a ratio between a width in the track width direction of the convex portion of the conductive layer and a width in the track width direction of the concave portion of the conductive layer, a deviation in the height direction concerning a surface intersecting the height direction of the conductive layer is obtained, and then based on the deviation in the height direction of the magnetic detection element layer and the deviation in the height direction of the conductive layer, the medium facing surface is ground with the conductive layer as a resistance sensor so that the height of the magnetic detection element layer be a desired value. | 11-20-2008 |
20080285178 | Thin film magnetic head characterized in bias-applying layer - A thin film magnetic head comprises a lower magnetic shield layer and an upper magnetic shield layer which are mutually opposed in the layering direction, a magnetoresistance effect element having a free layer, and a bias-applying layer which applies a bias magnetic field to the magnetoresistance effect element. The free layer is positioned between the lower magnetic shield layer and the upper magnetic shield layer, and is positioned on the side of the media-opposed surface. The bias-applying layer has a first portion, a second portion, and a third portion. The first portion and the second portion are positioned at a distance in the track width direction so as to enclose the magnetoresistance effect element therebetween. The third portion is positioned either between the magnetoresistance effect element and the lower magnetic shield layer or between the magnetoresistance effect element and the upper magnetic shield layer, and connects the first portion and the second portion. | 11-20-2008 |
20090034121 | Magnetic head for perpendicular magnetic recording with coil wound around pole layer - A magnetic head includes a medium facing surface, a coil, and a pole layer that generates a write magnetic field. The pole layer includes: a track width defining portion having a first end located in the medium facing surface and a second end opposite to the first end; and a wide portion connected to the second end. The first end defines the track width. The track width defining portion has a width taken in the track width direction, and the wide portion has a width taken in the track width direction that is greater than the width of the track width defining portion taken in the track width direction. The coil is helically wound only around the track width defining portion of the pole layer, and has a portion located between the medium facing surface and the wide portion. | 02-05-2009 |
20090080491 | METHOD FOR EVALUATING THE DETERIORATION OF MAGNETO-RESISTIVE EFFECT DEVICE - The estimation method of the invention for estimating the deteriorations of a magneto-resistive effect device by heat shocks involves applying heat shocks by laser irradiation to a structure including a thin-film magnetic head comprising a magneto-resistive effect device to propagate them to the magneto-resistive effect device, thereby causing the deteriorations of the magneto-resistive effect device. Thus, (1) the deterioration mode phenomenon of “local overheating plus vibration” can be imitated in a simple yet very approximate state so that a device likely to undergo characteristics deteriorations due to the thermal asperity problem can be detected early at an initial fabrication process stage, and (2) what specifications a head device structure less likely to offer the thermal asperity problem is in can be judged at a product development stage. | 03-26-2009 |
20090109577 | MAGNETO-RESISTIVE EFFECT DEVICE OF THE CPP STRUCTURE AND MAGNETIC DISK SYSTEM - The invention provides a magneto-resistive effect device of the CPP structure comprising a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked together and formed with the nonmagnetic intermediate layer sandwiched between them. The first ferromagnetic layer and the second ferromagnetic layer are magnetically coupled via the nonmagnetic intermediate layer such that the magnetizations of the first ferromagnetic layer and the second ferromagnetic layer are antiparallel with each other, wherein the mutually antiparallel magnetizations of two magnetic layers lie in a medium opposite plane or front to rear direction and in a rear to front direction. The second ferromagnetic layer is divided by a nonmagnetic intervening layer into a front second ferromagnetic layer and a rear second ferromagnetic layer on the way from the front to the rear, and the front second ferromagnetic layer and a front portion of the first ferromagnetic layer located at a position that makes a pair with the front second ferromagnetic layer via the nonmagnetic intermediate layer defines a substantial magnetic sensor portion with a sense current applied to it in a stacking direction. It is thus possible not only to make use of a structure capable of narrowing the read gap (between the upper and the lower shield) to make improvements in linear recording densities thereby meeting recent demands for ultra-high density recording, but also to get around a problem of unneeded information being written on the medium (media) and make the device less likely to be affected by the magnetic field, thereby enhancing the stability of operation of the device itself as well. | 04-30-2009 |
20090130491 | Magneto-resistive element for a magneto-resistive device and methof of manufacturing thereof - A magnetoresistive element (MR element) for reading a change in a magnetic field of a magnetic recording medium includes first and second electrode layers for providing a sensing current, which are perpendicular to an air bearing surface (ABS) facing the magnetic recording medium, first and second free layers which have a magnetization direction which changes in accordance with an external magnetic field, and a spacer layer composed of non-magnetic material. A ratio of a representative width and a representative length of each of the first and second free layers is at least 2 to 1, to thereby provide initial magnetizations along a direction of the representative length of each of the first and second free layers. | 05-21-2009 |
20090145878 | Thin-film patterning method for magnetoresistive device - The thin-film patterning method for a magnetoresistive device comprises forming a functional layer on a substrate; forming a first mask layer above the functional layer; forming a patterned resist on the first mask layer; etching the first mask layer by using the resist; removing the resist; forming a second mask layer by atomic layer deposition, the second mask layer covering a step defined by an edge of the first mask layer; dry-etching the second mask layer in a thickness direction of the substrate so as to leave the second mask layer on a side face of the step; removing the first mask layer so as to expose the functional layer under the first mask; and dry-etching the functional layer by using the second mask layer. | 06-11-2009 |
20090154024 | THIN-FILM MAGNETIC HEAD WITH THROUGH HOLES REACHING MEDIUM-OPPOSED SURFACE - Provided is a thin-film magnetic head for reading data from a magnetic recording medium and/or writing data to a magnetic recording medium, in which the magnetic spacing can be controlled appropriately by stably adjusting the pressure working between the thin-film magnetic head and the magnetic recording medium according to the change of conditions such as the change over time. This thin-film magnetic head comprises at least one through hole reaching a surface opposed to the magnetic recording medium of the thin-film magnetic head, for adjusting a pressure working between the thin-film magnetic head and the magnetic recording medium. Preferably, the head further comprises at least one flow-amount control means for controlling the flow amount of gas that flows via the at least one through hole. | 06-18-2009 |
20090190271 | Magnetoresistive element and magnetic head - An MR element includes a first ferromagnetic layer, a second ferromagnetic layer, a spacer layer disposed between the first and second ferromagnetic layers; and an antiferromagnetic layer disposed on a side of the first ferromagnetic layer farther from the spacer layer. The antiferromagnetic layer is disposed away from a detection surface. The first ferromagnetic layer includes: a first portion having an end face located in the detection surface and a rear end opposite to the end face; and a second portion located away from the detection surface and connected to the rear end of the first portion. The first portion has a first surface touching the spacer layer, and a second surface that is opposite to the first surface and that does not touch the antiferromagnetic layer. The second portion has a third surface touching the antiferromagnetic layer, and a fourth surface opposite to the third surface. The distance between the first surface and the second surface is smaller than the distance between the third surface and an imaginary plane including the first surface. | 07-30-2009 |
20090231762 | MAGNETORESISTIVE EFFECT ELEMENT AND THIN-FILM MAGNETIC HEAD WITH THE MAGNETORESISTIVE EFFECT ELEMENT - An MR element includes a pinned layer, a free layer and a nonmagnetic space layer or a tunnel barrier layer sandwiched between the pinned layer and the free layer. A magnetization direction of the free layer is substantially perpendicular to a film surface thereof, and a magnetization direction of the pinned layer is substantially parallel to a film surface thereof. | 09-17-2009 |
20090237833 | MAGNETIC TAPE APPARATUS USING PERPENDICULAR MAGNETIC RECORDING - Provided is a magnetic tape apparatus using perpendicular magnetic recording, which has the function corresponding to an soft-magnetic under layer with sufficiently large thickness and enables the magnetic tape to maintain life sufficiently. This magnetic tape apparatus comprises: a tape head comprising at least one write head element for perpendicular magnetic recording; and a soft-magnetic capstan belt having a surface contact with the magnetic tape and pressing the magnetic tape to the tape head at least during recording, for controlling running speed of the magnetic tape by causing the magnetic tape to run together with the soft-magnetic capstan belt. Further it is preferable that at least two capstan-belt axes are further provided, and the soft-magnetic capstan belt is a loop running among the at least two capstan-belt axes. | 09-24-2009 |
20100040957 | METHOD OF MEASURING DIMENSION OF PATTERN AND METHOD OF FORMING PATTERN - A method of measuring dimension of a first pattern with a narrow first width, and a second pattern with a second width wider than the first width of the first pattern and formed in a symmetrical appearance with respect to the pattern center, the second pattern having edges opposed to each other defining the second width, includes a step of forming a pair of first dummy patterns each having a narrow width, the pair of first dummy patterns being spaced from the edges of the second pattern respectively by a distance approximate to the first width of the first pattern, a first measurement step of measuring, using a dimension measuring device, a spaced distance of one of the first dummy patterns from the edge of the second pattern and a width of the one of the first dummy patterns within the same field of view of the dimension measuring device, a second measurement step of measuring, using the dimension measuring device, a width of the first pattern under the same measurement condition as that of the first measurement step, and a calculation step of calculating a width of the second pattern from W | 02-18-2010 |
20100061023 | MAGNETIC HEAD DEVICE AND MAGNETIC DISK DRIVE APPARATUS WITH THE MAGNETIC HEAD DEVICE - A magnetic head device includes a magnetic head section having a first free layer with a magnetization orientation that is not previously defined but changes depending upon only external magnetic field applied, a second free layer with a magnetization orientation that is not previously defined but changes depending upon only external magnetic field applied, a nonmagnetic intermediate layer sandwiched between the first free layer and the second free layer, a first electrode layer stacked on a surface of the first free layer opposite to the nonmagnetic intermediate layer, and a second electrode layer stacked on a surface of the second free layer opposite to the nonmagnetic intermediate layer; a sense-current supply means for flowing a sense current across the first electrode layer and the second electrode layer of the magnetic head section; and a frequency divider circuit for dividing by two a frequency of an output signal produced across the first electrode layer and the second electrode layer of the magnetic head section. | 03-11-2010 |
20100146774 | Method and Apparatus for Lapping Magnetic Head Slider, and Manufacturing Method of Thin-Film Magnetic Head - A method of lapping a magnetic head slider includes a step of lapping a lapping surface of a row bar provided with a plurality of MR read head elements arranged along at least one line, a step of obtaining at least one output signal from at least one of the plurality of MR read head elements of the row bar during lapping, the at least one output signal corresponding to element resistance, a step of detecting at least one peak value of the obtained at least one output signal, and a step of controlling an amount of lapping of the row bar depending upon the detected at least one peak value. | 06-17-2010 |
20100202088 | Magnetoresistive element, thin film magnetic head, magnetic head slider, head gimbal assembly, head arm assembly and magnetic disk device - The invention is devised to provide a magnetoresistive element that is hardly susceptible to harmful influence of unnecessary magnetic fields and noise of heat even when reduction in size is achieved to be adaptable to higher recording density, and therefore that is excellent in operational reliability. The magnetoresistive element includes a stacked structure including, in order: a magnetically pinned layer whose magnetization direction is fixed in a given direction; a non-magnetic layer; a magnetically free layer whose magnetization direction changes according to an external magnetic field; and an antiferromagnetic bias layer exchange-coupled with the magnetically free layer. The exchange-coupling magnetic field between the magnetically free layer and the antiferromagnetic bias layer is smaller than a saturation magnetic field of the magnetically free layer. | 08-12-2010 |
20110025320 | MAGNETIC SENSOR - A magnetoresistive element includes magnetoresistive films each having an upper surface and a lower surface, and conductors combining the magnetoresistive films in series and including top electrodes and bottom electrodes. Each one of the top electrodes and corresponding one of the bottom electrodes oppose each other to sandwich corresponding one of the magnetoresistive films. Each electrode of the top electrodes and the bottom electrodes includes a stem section and a branch section, the stem section extending in a direction along a series alignment direction of the magnetoresistive films, and the branch section extending along the lamination plane in a direction intersecting a direction in which the stem section extends. The branch section in the top electrode is in contact with an upper surface of the corresponding magnetoresistive film, and the branch section in the bottom electrode is in contact with a lower surface of the corresponding magnetoresistive film. | 02-03-2011 |
20110025321 | MAGNETIC SENSOR - A magnetic sensor includes first to fourth MR elements. The first and second MR elements are connected at respective ends thereof through a first connecting portion in a central region. The third and fourth MR elements are connected at respective ends thereof through a second connecting portion that crosses the first connecting portion with a distance in a thickness direction in the central region. The first and fourth MR elements are connected at respective other ends thereof through a third connecting portion, and the second and third MR elements are connected at respective other ends thereof through a fourth connecting portion. Resistance values of the first and third MR elements change in a same increasing/decreasing direction, whereas resistance values of the second and fourth MR elements change in an increasing/decreasing direction opposite to the first and third MR elements, depending on an external signal magnetic field. | 02-03-2011 |
20110025322 | MAGNETO-RESISTANCE EFFECT ELEMENT AND SENSOR - A magneto-resistance effect element for a sensor to sense a variation in externally applied magnetism includes a pinned layer having a fixed magnetization direction, a free layer having a magnetization direction which varies in response to an external magnetic field, and an intermediate layer provided between the pinned layer and the free layer. The pinned layer has a planar shape which is long in the fixed magnetization direction and which is short in a direction orthogonal to the fixed magnetization direction. Moreover, the pinned layer preferably has a planar shape in which the pinned layer is divided into a plurality of sections. | 02-03-2011 |
20110068786 | MAGNETIC SENSOR AND MANUFACTURING METHOD THEREOF - A magnetic sensor includes: a first and a second magnetoresistive elements each including: a magnetization free layer; a nonmagnetic spacing layer; a magnetization pinned layer having one or more first layers of a first group of ferromagnetic layers and one or more second layers of a second group of ferromagnetic layers, in which the first layer and the second layer are stacked alternately with a nonmagnetic coupling layer in between, and so antiferromagnetically coupled to each other as to have opposite magnetizations to each other; and an antiferromagnetic layer pinning magnetization orientation in the one or more first and the second layers. The first layers in the first magnetoresistive element are one more in number than that of the one or more second layers. The number of the one or more first layers and that of the one or more second layers in the second magnetoresistive element are equal. | 03-24-2011 |
20110194221 | ELECTRONIC CIRCUIT BOARD, MAGNETIC SENSOR, AND METHOD FOR PROTECTING POWER SUPPLY OF ELECTRONIC CIRCUIT - An electronic circuit board includes a TMR element having two terminals connected to a power supply and a ground, respectively, at least through a lead. After a breakdown of a tunnel barrier film of the TMR element, at least a part of the lead breaks by an overcurrent due to a short circuit between the two terminals. | 08-11-2011 |
20110221433 | MAGNETIC SENSOR - A magnetic sensor includes a spin valve-type magneto-resistive element, a voltage detection part, a coil, and a current control part, the coil being configured to apply a measuring magnetic field to the spin valve-type magneto-resistive element upon application of a current, the voltage detection part being configured to output a detection signal to the current control part upon detecting an output voltage of the spin valve-type magneto-resistive element reaching a predetermined voltage value, the current control part being configured to control the current to unidirectionally increase or unidirectionally decrease a strength of the measuring magnetic field from an initial value, but upon input of the detection signal, control the current to return the strength of the measuring magnetic field to the initial value, the initial value being a magnetic field strength where the spin valve-type magneto-resistive element reaches saturation magnetization. | 09-15-2011 |
20130134969 | THREE-DIMENSIONAL MAGNETIC FIELD SENSOR AND METHOD OF PRODUCING SAME - A three-dimensional magnetic field sensor includes a substrate having an element placement surface that is planar, and first, second and third MR elements disposed on a side of the element placement surface of the substrate and integrated with the substrate. Each of the first, second and third MR elements includes a magnetization pinned layer, a nonmagnetic layer, and a free layer. The magnetization pinned layer of the first MR element has a magnetization direction that is pinned in an X direction parallel to the element placement surface. The magnetization pinned layer of the second MR element has a magnetization direction that is pinned in a Y direction parallel to the element placement surface and different from the X direction. The magnetization pinned layer of the third MR element has a magnetization direction that is pinned in a Z direction perpendicular to the element placement surface. | 05-30-2013 |