JP3658491B2 - Thin-film magnetic head, manufacturing method thereof, and magnetic disk apparatus using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel magnetic disk device used for recording and reproducing information such as a computer and a thin film magnetic head used therefor.
[0002]
[Prior art]
In a magnetic disk device used for storing information such as a computer, a data signal is recorded and reproduced on a magnetic disk by a magnetic head. In order to increase the storage capacity per unit area of the magnetic disk device, it is necessary to increase the surface recording density. As a method for increasing the surface recording density, there is a method for increasing the track density and the linear recording density. A method for increasing the track density is to reduce the track width of the head that determines the track width. In the case of an induction type magnetic head also used for recording and reproduction, the surface recording density is several hundred Mbit / in.²As a result, there has been a problem that the reproduction output becomes smaller as the track width becomes smaller. Therefore, the head of the resistance resistance effect type (MR head) using the anisotropic magnetoresistive effect is mounted for reproduction, and the conventional type is used for recording. A recording / reproducing separated type thin film magnetic head using the above induction type head is used. In the MR head, the thickness of each layer is about 10 to 20 nm and has a heat resistance temperature of 250 ° C. or higher. The recording head has a structure having upper and lower magnetic cores, a gap film, a conductor coil, and an insulating film that insulates the conductor coil and the magnetic core. It is widely known that a thermosetting photoresist can be used as an insulating film between the conductor coil and the upper and lower magnetic cores. As conditions for curing the insulating film, several hours to several tens of hours are required at 250 ° C. or higher, and the current MR head does not deteriorate characteristics even under these conditions. JP-A-1-235016 discloses an example of a thin film magnetic head using a photoresist cross-linked by a heat-activated cross-linking agent. In addition to the photoresist, JP-A-6-28631 discloses an example of a thin film magnetic head using a ladder type silicone resin as an insulating film.
[0003]
Furthermore, the surface recording density is several Gbit / in.²When this is the case, the track width is further reduced, and the output is insufficient even in the reproducing head (MR head) using the anisotropic magnetoresistance effect. Therefore, it is necessary to increase the reproduction output by using a giant magnetoresistive head (GMR head) using a giant magnetoresistive effect that can obtain a larger resistance change rate. What shows a giant magnetoresistance effect is a multilayer type of a ferromagnetic metal film such as Co or Fe and a nonmagnetic metal film such as Cr or Cu, and sandwiches both sides of a nonmagnetic metal film such as Cr or Cu between magnetic films, Spin valve type and Al that obtain the rate of resistance change by fixing the magnetization of one magnetic film and rotating the magnetization of the non-fixed magnetic film₂O_ThreeAnd SiO₂There are types such as a tunnel junction type in which an insulating film such as a magnetic film is sandwiched and a resistance change rate is obtained by a tunnel effect through the insulating film. As a magnetic recording apparatus using the giant magnetoresistive effect, JP-A-8-7235 discloses an example using a spin valve type head.
[0004]
[Problems to be solved by the invention]
In the giant magnetoresistive film, the thickness of each layer is several tens of nm in any of the multilayer film type, the spin valve type, and the tunnel junction type, but for high density recording, for example, 3 nm or less is required. Therefore, the heat resistance is low due to factors such as easy diffusion at the interface of each layer, and the heat resistance temperature is about 230 ° C. For this reason, there is a problem in that the characteristics of the film are deteriorated and the resistance change rate is lowered by the thermosetting treatment (about 250 ° C., several hours) of the insulating film made of the photoresist in the typical manufacturing process of the recording head described above. . Therefore, this thermosetting treatment has been a major obstacle to improving the performance of the magnetic head and improving the surface recording density of the magnetic disk device.
[0005]
The gap film is Al.₂O_ThreeAnd SiO₂Inorganic films such as these are used. However, if the adhesion of the insulating film is low, a defect that the gap film and the insulating film peel off often occurs. Increasing the heat treatment temperature of the insulating film improves the adhesion, but as mentioned above, the high heat treatment temperature is difficult to apply in the sense of degrading the properties of the giant magnetoresistive film consisting of a thin multilayer film, and is cured at a low temperature. It is necessary to use a material with high adhesion that can be used. In the invention of JP-A-1-235016, the heat treatment conditions can be reduced to 15 hours at 80 ° C. by using a photoresist cross-linked by a heat-activated cross-linking agent. However, if the heat treatment temperature is too low, the photoresist does not flow and the taper angle at the end of the photoresist becomes high, which causes a problem that the step coverage of the upper magnetic core formed on the insulating film is deteriorated. Further, when the baking temperature of the insulating film is low, the adhesive strength of the photoresist is reduced, and thus a defect that the pattern peels occurs. In the case where a ladder type silicone resin is used instead of the photoresist of the invention of JP-A-6-28631, the heat treatment temperature is higher than that of the photoresist, and a heat treatment of 300 to 350 ° C. or more is required for one hour or more. As described above, the rate of change in resistance is lost not only in the giant magnetoresistive film but also in the MR film. Japanese Patent Laid-Open No. 8-7235 does not show an insulating film of a recording head.
[0006]
An object of the present invention is to provide a giant film having an insulating film that can be cured under heat treatment conditions at a low temperature and does not deteriorate the magnetic properties of a giant magnetoresistive film such as a multilayer film type, a spin valve type, and a tunnel junction type, and has excellent adhesion The present invention provides a recording / reproducing separation type thin film magnetic head using the magnetoresistive effect, a manufacturing method thereof, and a high recording density magnetic disk device equipped with the same.
[0007]
[Means for Solving the Problems]
The present invention relates to a lower magnetic film, a magnetic circuit that is laminated on the lower magnetic film, one end is connected to the lower magnetic film, and the other end faces the lower magnetic film through a magnetic gap, together with the lower magnetic film. Forming an upper magnetic core, a conductor coil provided between the lower magnetic film and the upper magnetic core, and an insulating film for electrically insulating the lower magnetic film, the upper magnetic core and the conductor coil from each other In the thin film magnetic head, the insulating film is obtained by curing a photoresist, a crosslinking agent, and a crosslinking accelerator of the photoresist and the crosslinking agent.
[0008]
The crosslinking agent is preferably at least one of melamine and epoxy. The crosslinking accelerator is preferably an organic compound that generates an acid, and particularly an organic compound that generates an acid by heating.
[0009]
Specific examples of the crosslinking accelerator include bromoacetylbenzene, p-bis (bromoacetyl) benzene, m-bis (bromoacetyl) benzene, 1,3,5-tris (bromoacetyl) benzene, 1,3,5- There are tris (dibromoacetyl) benzene and 1,3,5-tris (chloroacetyl) benzene.
[0010]
The photoresist is preferably an acid curable phenolic resin, particularly preferably a novolak.
[0011]
The present invention provides a magnetoresistive thin film magnetic head in which an antiferromagnetic layer, a first magnetic layer serving as a fixed layer, a nonmagnetic layer, and a second magnetic layer serving as a free layer are sequentially stacked.
The thicknesses of the first magnetic layer, the second magnetic layer, and the nonmagnetic layer are 3 nm or less.
[0012]
The present invention relates to a recording / reproducing separated head having an inductive recording head integrally formed on a magnetoresistive reproducing head via a magnetic shield.
The recording head has an upper magnetic core, one end stacked on the magnetic shield is connected to the magnetic shield and the other end is opposed through a magnetic gap, and forms a magnetic circuit together with the magnetic shield, and the magnetic shield; A conductor coil provided between the upper magnetic core and an insulating film that electrically insulates the magnetic shield, the upper magnetic core, and the conductor coil from each other; Consists of a resist, a crosslinking agent and a crosslinking accelerator,
The reproducing head has a nonmagnetic layer, preferably a ferromagnetic first and second magnetic layers partitioned by a metal layer, and an antiferromagnetic layer provided connected to one of the magnetic layers. The magnetization direction of the first magnetic layer of the ferromagnetic material is perpendicular to the magnetization direction of the second layer when the applied magnetic field from the recording medium is zero.
[0013]
The present invention relates to a recording / reproducing separated type thin film magnetic head having an inductive recording head integrally formed on a magnetoresistive effect type reproducing head via a magnetic shield.
The recording head is stacked on the magnetic shield, one end is connected to the magnetic shield and the other end is opposed through a magnetic gap to form a magnetic circuit together with the magnetic shield, and the magnetic shield and the upper portion A conductive coil provided between the magnetic core and an insulating film that electrically insulates the magnetic shield, the upper magnetic core and the conductive coil from each other, the insulating film being a photoresist mainly composed of a novolak resin; And a crosslinking agent and a crosslinking accelerator,
In the reproducing head, an antiferromagnetic layer, a first magnetic layer serving as a fixed layer, a nonmagnetic layer, preferably a metal layer thereof, and a second magnetic layer serving as a free layer are sequentially laminated,
The thickness of the first magnetic layer, the nonmagnetic layer, and the second magnetic layer is 3 nm or less.
[0014]
In the present invention, a magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive effect reproducing head for reproducing the information written on the magnetic disk are integrally formed. In a head disk assembly comprising a recording / reproducing separation type thin film magnetic head and a driving means for rotating the disk, the recording head or / and the reproducing head is composed of the above-mentioned thin film magnetic head, and 3 Gbit / in.²It has the above recording density.
[0015]
In the present invention, a magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive effect reproducing head for reproducing the information written on the magnetic disk are integrally formed. In a magnetic disk apparatus having a plurality of head / disk assemblies including a recording / reproducing separated type thin film magnetic head and a driving means for rotating the disk, the recording head and / or the reproducing head is composed of the above-described thin film magnetic head. It is characterized by that.
[0016]
The present invention relates to a method of manufacturing a recording / reproducing separated type head in which an induction type recording head is integrally formed on a magnetoresistive effect type reproducing head via a magnetic shield.
The reproducing head includes a ferromagnetic first and second magnetic layers partitioned by a nonmagnetic layer and an antiferromagnetic layer provided in contact with either of the magnetic layers, and is applied from a recording medium. A reproducing head manufacturing process in which the magnetization direction of the first magnetic layer of the ferromagnetic material is perpendicular to the magnetization direction of the second layer when the magnetic field is zero;
An upper magnetic core that forms a magnetic circuit together with the magnetic shield with one end connected to the magnetic shield and the other end opposed to each other via a magnetic gap on the magnetic shield after the manufacturing process of the reproducing head; Conductor coil provided between the magnetic core and the upper magnetic core, and a photoresist, a crosslinking agent, and a crosslinking accelerator between the photoresist and the crosslinking agent, which electrically insulate the magnetic shield, the upper magnetic core and the conductor coil from each other. And a recording / reproducing separation type thin-film magnetic head.
[0017]
The present invention relates to a recording / reproducing separated type thin film magnetic head in which an inductive recording head is integrally formed on a magnetoresistive effect type reproducing head via a magnetic shield.
An antiferromagnetic layer, a first magnetic layer serving as a fixed layer, a nonmagnetic layer, and a second magnetic layer serving as a free layer are sequentially stacked,
A reproducing head manufacturing process in which the thickness of the first magnetic layer, the second magnetic layer, and the nonmagnetic layer is 3 nm or less;
After the reproducing head manufacturing process, an upper magnetic core that is laminated on the magnetic shield and has one end connected to the magnetic shield and the other end opposed to each other through a magnetic gap to form a magnetic circuit with the magnetic shield; A conductor coil provided between the magnetic shield and the upper magnetic core, a photoresist, a crosslinking agent, and a bridge between the photoresist and the crosslinking agent that electrically insulate the magnetic shield, the upper magnetic core, and the conductor coil from each other. And a recording head manufacturing process for forming an insulating film made of a promoter.
[0018]
In the present invention, the surface recording density is 3 Gbit / in.²Above, preferably 5Gbit / in²In the magnetic disk apparatus described above, an inductive thin film head is used for recording / reproducing separated thin film magnetic head recording utilizing the spin valve giant magnetoresistive effect for reproduction.
[0019]
The portion that generates the giant magnetoresistance effect of the recording / reproducing separated type magnetic head is composed of a multilayer film of three or more layers.
[0020]
The multilayer film of the recording / reproducing separation type magnetic head includes a layer having a film thickness of 3 nm or less, and a photoresist and a cross-linking agent are used as insulating films of the recording coil and the upper and lower magnetic cores of the recording separation type thin film magnetic head. And using a cured and mixed cross-linking accelerator of the photoresist and the cross-linking agent,
The main component of the photoresist is a novolac resin,
The crosslinking agent is melamine or epoxy,
The cross-linking accelerator generates heat upon receiving heat.
[0021]
The crosslinking accelerator includes bromoacetylbenzene, p-bis (bromoacetyl) benzene, m-bis (bromoacetyl) benzene, 1,3,5-tris (bromoacetyl) benzene, 1,3,5-tris (dibromo). Acetyl) benzene, and one or a mixture of two or more of 1,3,5-tris (chloroacetyl) benzene,
The curing is performed by heat curing.
[0022]
As described above, in order to increase the recording density of the magnetic disk, it is essential to improve the performance of the magnetic head. In order to achieve high sensitivity, it is necessary to separate the recording head and the reproducing head and use various magnetoresistance effects for the reproducing head. Especially, surface recording density 5Gbit / in²In this case, it is necessary to use a giant magnetoresistive effect such as a spin valve type or a tunnel junction type from the viewpoint of the output of the reproducing head. At this time, the thinnest film thickness of the giant magnetoresistive effect film is very thin, 3 nm or less, so that the heat resistance deteriorates. For this reason, the characteristics of the read head are impaired by the temperature of the thermosetting treatment of the photoresist used for the interlayer insulating film for maintaining the insulation between the conductor coil of the recording head and the upper and lower magnetic cores normally produced after the read head is formed. It is. For this reason, it is necessary to lower the temperature of this thermosetting treatment. A photoresist used as an insulating film uses a novolak resin as a base resin and a diazonaphthoquinone series as a photosensitizer, and the thermosetting start temperature is 250 ° C. or higher. The photoresist for curing at a low temperature may be a novolak resin used in the production of the above-mentioned normal thin film magnetic head or semiconductor element and a diazonaphthoquinone series as a photosensitive agent. As for the melamine resin, Cymel 300, Cymel 303, Cymel 325, and the like are available from Mitsui Cytec. Since melamine and epoxy do not affect the photosensitivity at the time of exposure, the pattern accuracy and stability are exactly the same as those of ordinary photoresists. Further, the flatness of a step such as a coil is equivalent to that when a conventional resist is used.
[0023]
Melamine and epoxy do not crosslink in the absence of a catalyst even when mixed with a novolak resin and are heated, so that they do not crosslink, but rapidly crosslink and cure by heating in the presence of an acid catalyst. When an acid catalyst is present in the varnish-like resist, crosslinking starts from a relatively low temperature of about 90 ° C., and thus crosslinking starts from pre-baking after the resist coating, so that an accurate pattern cannot be formed. Therefore, by mixing the resist that generates acid by baking after pattern formation, an accurate pattern can be formed, and in subsequent baking, melamine or epoxy and novolak resin can be cross-linked and cured. It becomes possible. Examples of such an acid generator include bromoacetylbenzene, p-bis (bromoacetyl) benzene, m-bis (bromoacetyl) benzene, 1,3,5-tris (bromoacetyl) benzene, 1,3,5- There are tris (dibromoacetyl) benzene and 1,3,5-tris (chloroacetyl) benzene. An acid generator such as 1,3,5-tris (bromoacetyl) benzene decomposes at about 150 ° C. to generate an acid. For this reason, melamine or epoxy and novolak resin start to crosslink gradually from 150 ° C. However, novolak resin mixed with melamine or epoxy is easier to flow than novolak resin alone, and therefore baked at 150 ° C or higher. Thus, the taper angle at the pattern end can be reduced. Since the taper angle is low, there is no problem with the step coverage of the upper magnetic core formed on this insulating film. In order to obtain high adhesion as an insulating film, it is desirable to bake at 150 to 200 ° C. for 30 minutes or more as baking conditions.
[0024]
As described above, the insulating film used in the present invention has significantly higher baking conditions than the baking conditions for several hours to several tens of hours at 250 ° C. or higher using a conventional resist while maintaining sufficient adhesion. Can be relaxed. Therefore, even in a giant magnetic resistance effect film of a spin valve type or tunnel junction type composed of an ultrathin film of 3 nm or less, the magnetic characteristics can be sufficiently maintained, and the surface recording density is 5 Gbit / in.²A magnetic disk drive equipped with a high-performance magnetic head capable of obtaining the reproduction output necessary to achieve the above can be manufactured.
[0025]
(1) Recording head
In the above-described thin film magnetic head for recording according to the present invention, a frame is formed on a substrate having a magnetic film serving as a lower magnetic core or an upper magnetic shield, a magnetic gap, a conductor coil, and an insulating film, and then a plating film is formed. Thereafter, the upper magnetic core is formed by etching the plating film while masking the region surrounded by the frame, and the track width wl with which the upper magnetic core is in contact with the magnetic gap is 1.5 μm. When the track width wl is 1.5 μm or less, the ratio (t / wl) between the track width wl and the thickness t of the upper magnetic core is preferably 2 or more.
[0026]
The ratio (w2 / w1) of the track width (wl) at which the upper magnetic core is in contact with the magnetic gap and the upper width (w2) of the upper magnetic core is preferably 1.3 or less.
[0027]
In the thin film magnetic head described above, a frame is formed on a substrate having a magnetic film serving as a lower magnetic core or upper magnetic shield, a magnetic gap, a conductor coil, and an insulating film, and then a plating film is formed, and then surrounded by the frame. When the upper magnetic core is formed by etching the plating film with a mask on the region to be etched, a resist is optimally formed on the substrate in the tip region of the substrate where the magnetic gap of the thin film magnetic head is formed. After forming the resist to a thickness and patterning the resist into a shape corresponding to at least the tip region of the upper magnetic core, the patterned resist is cured to form the tip region of the upper magnetic core. A first step of forming a corresponding first frame;
On the substrate on which the first frame is formed, a resist is applied to the rear region of the substrate on which the conductor coil and the insulating film of the conductor coil are formed so that the frame has an optimum thickness, and then Manufacturing to form the frame by patterning the resist to form a second frame corresponding to a portion formed in the rear region of the upper magnetic core so as to be integrated with the first frame It can be achieved by the method. Since the resist film thickness can be made thinner than usual, it is possible to resolve a narrow track pattern.
[0028]
Reactive ion etching may be used for the etching process, and the uppermost layer resist may be a Si-containing resist, or the multilayer film may be a three-layer film of an organic film, an intermediate film, and an uppermost layer resist. The intermediate film is made of an inorganic film, especially Si, SiO₂, Al, Al₂O_Three, Ti, TiO₂, Ta, Ta₂O_Three, W, Nb are preferred, especially SiO₂Is preferably sintered after sputtering or spin-on-glass application.
[0029]
The organic film is made of a resist, and after the first frame is formed, a curing process is performed, and the curing process is performed by deep ultraviolet irradiation or reactive ion etching. The organic film comprises at least one of polyimide and derivatives thereof, polydimethylglutarimide (PMGI) and derivatives thereof, polymethyl methacrylate (PMMA) and derivatives thereof, benzocyclobutene (BCB) and derivatives thereof, and epoxy and derivatives thereof. In addition, an electron beam resist can be used for the uppermost layer resist, an electron beam drawing method can be used for the exposure of the electron beam resist, and a phase shift method or a modified illumination method can be used for the exposure of the uppermost layer resist.
[0030]
Furthermore, the present invention provides an electroplating thin film of a Ni—Fe alloy in which at least one of the upper magnetic core and the lower magnetic core of the write magnetic core of the thin film magnetic head has Ni of 38 to 60 atomic% and Fe of 40 to 62 atomic%, or It is preferably made of a single layer film or a laminated film of Ni 75-86 atomic% -Fe alloy.
[0031]
The present invention further comprises a disk-shaped magnetic disk having a media transfer rate of 15 megabytes or more per second, a surface recording density of recorded data of 3 gigabits or more per square inch, and an information storage medium of 3.5 inches or less in diameter. The magnetic disk rotates at 4000 rpm or more at the time of recording / reproduction, the recording frequency is 45 MHz or more, and at least the upper magnetic core of the thin film magnetic head for recording has Ni 38 to 85 atomic% and Fe 15 to 62 atomic%. The recording magnetic head is made of a Ni—Fe alloy, the film thickness is 1 to 5 μm, the average crystal grain size is 500 μm or less, the specific resistance is 40 to 60 μΩcm, the coercive force in the hard axis direction is 1.0 Oe or less. The recording magnetomotive force is preferably 0.5 ampere turns or more.
[0032]
The magnetic core according to the present invention can include at least one of Co of 15 wt% or less and 1 or more of Mo, Cr, Pd, B, and In in a total amount of 3 wt% or less.
[0033]
(2) Playback head
The present invention relates to a magnetoresistive film in which a plurality of films having a size corresponding to the track width of a magnetic recording medium are stacked in multiple layers, and adjacent to both sides of a width direction region intersecting the stacking direction of the magnetoresistive film. And a pair of electrodes stacked on the magnetic domain control layer and electrically connected to the magnetoresistive effect film. The magnetoresistive effect film has a magnetization direction by a magnetic field from a magnetic recording medium. A single-layer or multiple-layer first ferromagnetic film with a variable magnetization, a single-layer or multiple-layer second ferromagnetic film with a fixed magnetization direction, a first ferromagnetic film, and a second ferromagnetic film A magnetoresistive head having a nonmagnetic film inserted between the antiferromagnetic film and the permanent magnet film that fixes the magnetization direction of the second ferromagnetic film. Then, a part of the pair of electrodes is laminated on the magnetoresistive film. The interval between the electrodes is formed to be narrower than the width of the magnetoresistive effect film, or the electrode is disposed at a position where current flows only in the central portion of the magnetoresistive effect film, and the interval is set to 1.3 μm or less. In particular, the interval can be further set to 0.25 to 1.0 μm.
[0034]
Among magnetoresistive heads that use the giant magnetoresistive effect, an antiferromagnetic film or a permanent magnet film that fixes the magnetization direction is directly laminated on the second ferromagnetic film. It is possible to adopt a configuration in which a part is laminated on the antiferromagnetic film or the permanent magnet film and the distance between the electrodes is narrower than the width of the magnetoresistive film.
[0035]
The present invention detects a magnetic field leaking from a recording medium having a ferromagnetic recording medium in which a signal is magnetically recorded, and a relative movement with respect to the disk by bringing a sliding surface close to the disk. In the magnetic recording / reproducing apparatus having the magnetic head, the magnetic head is provided in contact with either of the first and second magnetic layers of the ferromagnetic material partitioned by the nonmagnetic layer and the magnetic layer. And when the applied magnetic field is zero, the magnetization direction of the first magnetic layer of the ferromagnetic material is perpendicular to the magnetization direction of the second layer, and With or without means to fix the magnetization direction;
Means for generating a current in the magnetoresistive sensor;
Means for detecting a change in electrical resistance caused by rotation of the magnetization of the first layer as a function of the magnetic field detected by the magnetoresistive sensor, wherein the first and second magnetic layers are Co or a Co alloy. The antiferromagnetic layer is preferably a Cr—Mn alloy.
[0036]
The Cr—Mn alloy preferably contains 30 to 70 atomic% Mn, and is further selected from the group consisting of Co, Ni, Cu, Ag, Au, Pt, Pd, Rh, Ru, Ir, Os and Re. At least one may be contained in a total content of 0.1 to 30 atomic%. In particular, 5 to 15 atomic% is preferable.
[0037]
The permanent magnet film is a Co—Pt alloy, a Co—Cr—Pt alloy, or a Ti oxide, V oxide, Zr oxide, Nb oxide, Mo oxide, Hf oxide, Ta oxide, It is preferably composed of an alloy containing at least one element of W oxide, Al oxide, Si oxide, and Cr oxide, and in particular, it may be composed of (Equation 1) or (Equation 2). preferable.
[0038]
Co_aCr_bPt_c ... (Equation 1)
Or
(Co_aCr_bPt_c)_1-x(MO_y)_x ... (Equation 2)
(However, x: 0.01 to 0.20, y: 0.4 to 3, a: 0.7 to 0.9, b: 0 to 0.15, c: 0.03 to 0.15, M : Ti, V, Zr, Mo, Hf, Ta, W, Al, Si, and Cr)
In the multilayer film, an antiferromagnetic film is laminated on a first ferromagnetic film, a nonmagnetic film, a second ferromagnetic film, and a second ferromagnetic film. The multilayered magnetoresistive film and antiferromagnetic film are formed by laminating and then the width of the magnetoresistive film (first ferromagnetic film, nonmagnetic film, second ferromagnetic film). Both sides are collectively cut off so that the narrowest width is defined as, for example, 2.0 μm. The first ferromagnetic film is a free layer such as Ni₈₀Fe₂₀, Ni₆₈Fe₁₇Co₁₅, Co₆₀Ni₂₀Fe₂₀, Co₉₀Fe_Ten, Co or the like, and the film thickness is set to an optimum value between about 2 to 15 nm, for example. Nonmagnetic films include, for example,
Cu is used, and the film thickness is set to an optimum value between about 1 to 4 nm, for example. The second ferromagnetic film is made of, for example, Co as a fixed layer, and the film thickness is set to an optimum value between about 1 to 5 nm, for example. The second ferromagnetic film is a fixed layer, for example, Ni₈₀Fe₂₀, Ni₆₈Fe₁₇Co₁₅, Co₆₀Ni₂₀Fe₂₀, Co₉₀Fe_Ten, Co, etc., and a multilayer film in which several of these films are optimally stacked can also be used. For example, Cr₄₅Mn₄₅Pt_TenThis film thickness is set to about 30 nm, for example. In addition to the above, the antiferromagnetic film includes, for example, Fe₅₀Mn₅₀, Mn₈₀Ir₂₀, Ni₅₀Mn₅₀Etc. can also be used. The magnetization direction of the second ferromagnetic film is fixed so that it almost points to the medium facing surface by exchange coupling with the antiferromagnetic film. The magnetization direction of the first ferromagnetic film is set, for example, in the width direction of the magnetoresistive film, and this magnetization direction is changed in the direction perpendicular to the paper surface by the magnetic field of the magnetic recording medium. The antiferromagnetic film can be replaced with a permanent magnet.
[0039]
The magnetic domain control layer is composed of, for example, a laminated film in which a permanent magnet film and an orientation control base film are laminated, and the magnetic domain control layer is adjacent to both sides of a region in the width direction intersecting with the lamination direction of the magnetoresistive effect film. Are arranged. As the permanent magnet film constituting the magnetic domain control layer, for example, Co₇₅Cr_TenPt₁₅, Co₇₅Cr_TenTa₁₅For example, Cr is used for the orientation control base film. In addition, as the permanent magnet film constituting the magnetic domain control layer, for example, Co₈₀Pt₂₀Can also be used, and Co₇₅Cr_TenPt₁₅, Co₇₅Cr_TenTa₁₅, Co₈₀Pt₂₀ZrO for alloys such as₂, SiO₂, Ta₂O_FiveWhat added the oxides of these etc. can also be used. In these cases, the orientation control base film can be omitted. The first ferromagnetic film is controlled to a single magnetic domain by a magnetic field generated from the magnetic domain control layer. The magnetic domain control layer can also be composed of a laminated film of an antiferromagnetic film, a ferromagnetic film, and an orientation control base film. In this case, the antiferromagnetic film is Fe₅₀Mn₅₀, Mn₈₀Ir₂₀, Ni₅₀Mn₅₀, Cr₄₅Mn₄₅Pt_TenThe ferromagnetic film is selected from NiFe-based, CoFe-based, CoNi-based alloys, and the like, and the orientation control base film is preferably Ta. Further, NiO, CoO or the like can be used as the antiferromagnetic film, and in this case, the orientation control base film can be omitted.
[0040]
The pair of electrodes are respectively stacked on the magnetic domain control layer, and a part of each electrode is stacked on the antiferromagnetic film. Here, the lamination width of each electrode and the antiferromagnetic film is set to 0.5 μm, for example. That is, since the width of the magnetoresistive effect film is 2.0 μm or less, each electrode is laminated on the magnetic domain control layer and the antiferromagnetic film while keeping the electrode interval at 1.0 μm. Each electrode is made of a low-resistance metal such as Ta, Au, or Cu.
[0041]
In a spin valve head using an oxide such as NiO or CoO as an antiferromagnetic film, a magnetoresistive film is laminated on the antiferromagnetic film. Accordingly, the pair of electrodes are respectively stacked on the magnetic domain control layer, and a part of each electrode is stacked on the first ferromagnetic film. The antiferromagnetic film can be replaced with a permanent magnet.
[0042]
In order to increase the sensitivity of the spin valve head, the structure of the magnetoresistive film of the dual spin valve head, which is an application thereof, is composed of a second ferromagnetic film, a nonmagnetic conductor film, and a first ferromagnetic film on an antiferromagnetic film. A film, a nonmagnetic conductor film, a third ferromagnetic film, and an antiferromagnetic film are sequentially laminated. The material of each film is the same as described above.
[0043]
DETAILED DESCRIPTION OF THE INVENTION
Example 1
FIG. 1 is a schematic view of a hard disk device using a magnetoresistive effect reproducing head of a spin valve head according to the present invention. This apparatus has a disk rotation shaft 64 and a spindle motor 65 that rotates the disk rotation shaft 64 at a high speed. One or a plurality of (two in this embodiment) disks 50 are attached to the disk rotation shaft 64 at a predetermined interval. It has been. Therefore, each disk 50 rotates together with the disk rotating shaft 64. The disk 50 is a disk having a predetermined radius and thickness, and permanent magnet films are formed on both sides to serve as an information recording surface. The apparatus also has a head positioning rotary shaft 62 and a voice coil motor 63 for driving the head positioning rotary shaft 62 on the outside of the disk 50, and a plurality of access arms 61 are attached to the head positioning rotary shaft 62. A recording / reproducing head (hereinafter referred to as a head) 60 is attached to the tip of each access arm 61. Therefore, each head 60 moves on each disk 50 in the radial direction when the head positioning rotary shaft 62 rotates by a predetermined angle, and is positioned at a predetermined location. Further, each head 60 has a distance of about several tens of nanometers from the surface of the disk 50 due to the balance between the buoyancy generated when the disk 50 rotates at high speed and the pressing force of the gimbal that is an elastic body constituting a part of the access arm 61. Is held in. The spindle motor 65 and the voice coil motor 63 are respectively connected to a hard disk controller 66, and the hard disk controller 66 controls the rotational speed of the disk 50 and the position of the head 60.
[0044]
FIG. 2 is a perspective view of a magnetic head having an inductive recording head and a magnetoresistive effect reproducing head according to the present invention. The reproducing head having the lower magnetic shield 21, the magnetoresistive effect film 23, the magnetic domain control layer 25, and the electrode 11, the lower gap, and the upper gap are not shown. The upper magnetic shield 4 also serving as the lower magnetic core is mounted with an inductive recording head that generates magnetomotive force.
[0045]
FIG. 3 is a perspective view of the negative pressure slider. The negative pressure slider 70 has a negative pressure generation surface 78 surrounded by an air introduction surface 79 and two positive pressure generation surfaces 77 and 77 that generate levitation force, and further includes the air introduction surface 79 and two positive pressure generations. A groove 74 having a larger step than the negative pressure generating surface 78 is formed at the boundary between the surfaces 77 and 77 and the negative pressure generating surface 78. An air outflow end 75 includes an inductive recording head (to be described later) for recording information on a magnetic disk and a reproducing head (to be described later) for reproduction. The recording / reproducing separated type thin film magnetic head having the schematic structure shown in FIG. An element 76 is included.
[0046]
When the negative pressure slider 70 floats, the air introduced from the air introduction surface 79 is expanded on the negative pressure generation surface 78. At this time, an air flow toward the groove 74 is also created. In addition, there is an air flow from the air introduction surface 79 toward the air outflow end 75. Therefore, even if dust that floats in the air when the negative pressure slider 70 floats is introduced from the air introduction surface 71, it is introduced into the groove 74, pushed away by the air flow inside the groove 74, and from the air outflow end 78. It is discharged out of the negative pressure slider 70. Further, when the negative pressure slider 70 floats, there is always no air flow in the groove 74 and there is no stagnation, so that dust does not aggregate.
[0047]
FIG. 4 is an overall perspective view of a magnetic disk device which is an example of the present invention. The configuration of the magnetic disk apparatus includes: a magnetic disk for recording information; a DC motor (not shown) for rotating the magnetic disk; a magnetic head for writing and reading information; It is composed of a positioning device for changing the position, that is, an actuator and a voice coil motor. In these figures, five magnetic disks are attached to the same rotating shaft, and the total storage capacity is increased.
[0048]
FIG. 5 shows an example in which a disk array apparatus is assembled by combining a plurality of the above magnetic recording / reproducing apparatuses. In this case, since a plurality of magnetic recording / reproducing apparatuses are handled at the same time, the information processing capability can be increased and the reliability of the apparatus can be improved. In this case as well, it is needless to say that the performance (low error rate, low power consumption, etc.) of each magnetic recording / reproducing apparatus is better. Therefore, a high-performance recording / reproducing separated type head is indispensable.
[0049]
FIG. 6 is a configuration diagram illustrating the medium facing surface of the spin valve head according to the present embodiment. In FIG. 6, a spin valve head (giant magnetoresistive head) configured as a magnetoresistive head for reproduction includes a magnetoresistive film 10, a magnetic domain control layer 12, and a pair of electrodes 14. The film 10 is laminated on the antiferromagnetic film 16. The magnetoresistive film 10 is formed by laminating a plurality of films having a size corresponding to the track width of the magnetic recording medium. The multilayer film is composed of a first ferromagnetic film 18, a nonmagnetic film 20, and second ferromagnetic films 22 and 24, and the second ferromagnetic film 24 is laminated on the antiferromagnetic film 16. Yes. These multilayer films are stacked in a state of being cut off to a size corresponding to a predetermined width (width 26 of the magnetoresistive effect film). The first ferromagnetic film 18 is configured using, for example, NiFe, CoFe, CoNiFe, etc. as a free layer, and the film thickness is set to 5 nm (preferably 2 to 15 nm). For example, Cu is used for the nonmagnetic film 20, and the film thickness is set to 2 nm (preferably 1 to 5 nm). Each of the second ferromagnetic films 22 and 24 forms a laminated film as a fixed layer. For example, Co is used for the second ferromagnetic film 22 and the film thickness is set to 1 nm. For example, NiFe is used for the second ferromagnetic film 24. The film thickness is set to 1 nm, and preferably 1 to 5 nm for both. The antiferromagnetic film 16 is made of NiO and has a thickness of 50 nm (preferably
20 to 80 nm). The second ferromagnetic films 22 and 24 are fixed so that the magnetization direction thereof substantially points to the medium facing surface by exchange coupling with the antiferromagnetic film 16. The magnetization direction of the first ferromagnetic film 18 is set, for example, in the width direction of the magnetoresistive film, and this magnetization direction is changed in the direction perpendicular to the paper surface by the magnetic field of the magnetic recording medium. The first ferromagnetic film 18 is larger than the total thickness of the second ferromagnetic films 22 and 24 and has a size of about 2 to 3 times.
[0050]
The magnetic domain control layer 12 is composed of a laminated film in which a permanent magnet film 28 and an orientation control base film 30 are laminated. The magnetic domain control layer 12 is formed on both sides of a region in the width direction that intersects with the lamination direction of the magnetoresistive effect film 10. It is arranged adjacent to. For example, a CoCrPt alloy is used as the permanent magnet film 28, and Cr of 10 nm (preferably 5 to 20 nm) is used as the orientation control base film 30. The first ferromagnetic film 18 is controlled to a single magnetic domain by a magnetic field generated from the magnetic domain control layer 12. The magnetic domain control layer 12 is disposed at substantially the same height as the first ferromagnetic film 18 and has a thickness of 10 nm (preferably 4 to 30 nm, more preferably 5 to 15 nm).
[0051]
The pair of electrodes 14 are respectively stacked on the magnetic domain control layer 12, and a part of each electrode 14 is stacked on the first ferromagnetic film 18. That is, each electrode 14 is laminated on the first ferromagnetic film 18 and the magnetic domain control layer 12 with the electrode interval 32 maintained. Each electrode 14 is made of, for example, a metal such as Au, Cu, Ta, and the electrode interval 32 of each electrode 14 is set to be narrower than the width 26 of the magnetoresistive film.
[0052]
In the spin valve head, the output is proportional to the product of the specific resistance change Δρ inherent to the spin valve film and the cosine cos Δθ of the angle Δθ formed by the magnetization directions of the first and second ferromagnetic films. It is known that the spin valve head is more sensitive than the AMR head because the specific resistance change Δρ is more than twice as high as that of the AMR head. Here, assuming that the magnetization direction of the second ferromagnetic film is fixed perpendicularly to the medium facing surface, for example, directly below (minus 90 °), cosΔθ is the magnetization direction of the first ferromagnetic film and the medium Cos (θ + 90 °) can be written using the angle θ formed with the facing surface. That is, the output is proportional to sinθ. Therefore, in order to change the output linearly with respect to the change of θ, θ is preferably around 0 °. Therefore, the magnetization direction of the first ferromagnetic film is set so as to be substantially parallel to the medium facing surface, that is, substantially beside.
[0053]
FIG. 7 is a configuration diagram of a spin valve head that uses an alloy such as FeMn, NiMn, or CrMn instead of NiO as the antiferromagnetic film 16 of the spin valve head. Either one of the second ferromagnetic films 22 and 24 can be omitted. As shown in FIG. 7, the lamination direction of the magnetoresistive effect film 10 is different from that in FIG. 6, and an antiferromagnetic film 16 is laminated on the magnetoresistive effect film 10. 6 and 7, the antiferromagnetic film 16 can be replaced with a permanent magnet film. The thickness of each layer in this drawing is the same as in FIG. The magnetic domain control layer 12 is below the upper surface of the antiferromagnetic film 16.
[0054]
As another example of the film structure of the spin valve head, Ta (5 nm), NiFe (5 nm), CoFe (1 nm), Cu (2.5 nm), CoFe (3 nm), CrMnPt (30 nm) Each layer of Ta (5 nm) is sequentially laminated, and a Co—Cr—Pt alloy and an electrode 14 (Ta) are provided as hard bias layers at both ends. Thereby, the resistance change rate can be 6.5%. The upper CoFe layer is a fixed layer, and the lower CoFe layer and NiFe layer are free layers with respect to the magnetic field of the medium.
[0055]
As another example, Ta (5 nm), NiFe (5 nm), Cu (2 nm), Co (1 nm), FeNi (1 nm), CrMnPt (50 nm) and Ta (5 nm) layers are formed from the lower magnetic shield 1 side. A hard bias layer and electrodes similar to those described above are provided in order.
[0056]
FIG. 8 is a configuration diagram using a dual spin valve head which is an application thereof in order to increase the output of the spin valve head. As shown in FIG. 8, the magnetoresistive film 10 in this case has a first ferromagnetic film 18, second ferromagnetic films 22 and 24 whose magnetization directions are fixed, and a third ferromagnetic film 36. , 38, between the non-magnetic film 20 inserted between the first ferromagnetic film 18 and the second ferromagnetic film 22, and between the first ferromagnetic film 18 and the third ferromagnetic film 36. The second ferromagnetic films 22 and 24 are laminated on the antiferromagnetic film 16, and the antiferromagnetic film 40 is a third ferromagnetic film 36 and 38. It is the structure laminated | stacked on the top. The first ferromagnetic film 18 is configured using, for example, NiFe, CoFe, CoNiFe, etc. as a free layer, and the film thickness is set to 5 nm. For example, Cu is used for the nonmagnetic films 20 and 34, and the film thickness is set to 2 nm. The second ferromagnetic films 22 and 24 and the third ferromagnetic films 36 and 38 each constitute a laminated film as a fixed layer, and the second ferromagnetic film 22 and the third ferromagnetic film 36 include For example, Co is used, and the film thickness is set to 1 nm. For example, NiFe is used for the second ferromagnetic film 24 and the third ferromagnetic film 38, and the film thickness is set to 1 nm (preferably 0.5 to 3 nm). As the antiferromagnetic films 16 and 40, the most suitable films are selected from oxides such as NiO and CoO, FeMn series, NiMn series and CrMn series alloys. Here, the antiferromagnetic films 16 and 40 may be made of the same material or different materials, and may be further replaced with a permanent magnet. One of the second ferromagnetic films 22 and 24 can be omitted, and similarly, one of the third ferromagnetic films 36 and 38 can be omitted. The thickness of each other layer is the same as that of FIG.
[0057]
In each of the above spin valve heads, the permanent magnet film 28 can be replaced with a laminated film of a NiFe alloy and an antiferromagnetic film such as an FeMn alloy, MnIr alloy, NiMn alloy, or CrMn alloy. In this case, better characteristics can be obtained if the orientation control base film 30 is replaced with Ta or the like. The magnetic domain control layer 12 is formed below the upper surface of the magnetoresistive effect film 10.
[0058]
FIG. 9 is a cross-sectional view of an inductive type recording head used in the hard disk device of this embodiment. This thin film head is composed of a lower magnetic film 84 and an upper magnetic film 85. A nonmagnetic insulator 89 is attached between these magnetic films. A portion of the insulator defines a magnetic gap 88. The support is in the form of a slider having an air bearing surface (ABS), which is in close proximity to the rotating disk media during disk file operation.
[0059]
The thin film magnetic head has a back gap 90 formed by an upper magnetic film 85 and a lower magnetic film 84. The back gap 90 is separated from the magnetic gap by an intervening coil 87.
[0060]
The continuous coil 87 is a layer formed on the lower magnetic film 84 by plating, for example, and electromagnetically couples them. The coil 87 has an electrical contact at the center of the coil buried with the insulator 89, and there is a larger area as an electrical contact at the end of the outer end of the coil. The contacts are connected to an external electric wire and a read / write signal processing head circuit (not shown).
[0061]
In the present invention, it is preferable that the coil 87 made of a single layer has a slightly distorted elliptical shape, and the portion having a small cross-sectional area is disposed closest to the magnetic gap, and the distance from the magnetic gap is large. As it becomes, the cross-sectional area gradually increases.
[0062]
However, many elliptical coils are relatively densely packed between the back gap 190 and the magnetic gap 188, and the coil width or cross-sectional diameter is small in this area. Furthermore, a large cross-sectional reduction at the portion farthest from the magnetic gap results in a decrease in electrical resistance. Furthermore, an elliptical (ellipse) coil does not have corners, sharp corners or ends, and has low resistance to current. In addition, the elliptical shape requires less total length of the conductor than a rectangular or circular (annular) coil. As a result of these advantages, the total resistance of the coil is relatively small, heat generation is small, and moderate heat dissipation is obtained. Since the heat is reduced by a considerable amount, the thin film layer is prevented from collapsing, stretching, and expanding, and the cause of the ball tip protrusion at the ABS is eliminated.
[0063]
The elliptical coil shape whose width changes almost uniformly can be attached by a conventional plating technique which is cheaper than sputtering or vapor deposition. Other shapes, especially cornered coils, tend to have a structure with non-uniform width of plating adhesion. The removal of corners and sharp edges gives less mechanical stress to the resulting coil.
[0064]
In this embodiment, it is preferable that a large number of wound coils are formed between the magnetic cores in an approximately elliptic shape, the coil cross-sectional diameter gradually increases from the magnetic gap to the back gap, the signal output increases, and the heat generation Can be reduced.
[0065]
In this example, the upper and lower magnetic films of the inductive recording head were formed by the following electroplating method.
[0066]
Ni⁺⁺Amount: 16.7 g / l, Fe⁺⁺In a plating bath containing an amount: 2.4 g / l and other ordinary stress relaxation agents and surfactants, pH: 3.0, plating electric density: 15 mA / cm²An inductive thin-film magnetic head having upper and lower magnetic cores frame-plated under the conditions described above was fabricated. The track width is 1.0 μm and the gap length is 0.4 μm. The composition of this magnetic film is 42.4Ni-Fe (% by weight), and the magnetic properties are the saturation magnetic flux density (B_S) Is 1.64T, difficult axial coercive force (H_CH) Was 0.5 Oe, and the specific resistance (ρ) was 48.1 μΩcm. An upper magnetic core 85, a lower magnetic core 84 also serving as an upper shield layer, and a coil 87. A magnetoresistive element 86 for reproduction, an electrode for passing a sense current to the magnetoresistive element, a lower shield layer, and a slider are included. The crystal grain size of the magnetic core of this example was 100 to 500 mm, and the hard axis coercivity was 1.0 Oe or less.
[0067]
As a result of measuring the performance (overwrite characteristic) of the recording head according to the present invention evaluated with such a configuration, an excellent recording performance of about −50 dB was obtained even in a high frequency region of 40 MHz or higher.
[0068]
According to the present embodiment, a magnetoresistive (MR) effect sensor having a multilayer double spin, valve structure can obtain a large MR response with a low applied magnetic field. This MR structure is a laminated structure including first, second, and third ferromagnetic thin film layers formed on a substrate and separated by a thin film layer of a nonmagnetic metal material. The outer layers of the first and third ferromagnetic layers have their magnetization directions fixed, the intermediate second layer is soft magnetic, and when the applied magnetic field is zero, the outer two ferromagnetic layers It is substantially perpendicular to the fixed magnetization direction of the body layer. The magnetization directions of the first and third ferromagnetic layers are fixed in several ways, including hard bias or exchange bias with adjacent antiferromagnetic layers.
[0069]
The magnetization directions of the two outer ferromagnetic layers are fixed antiparallel to each other, and therefore each fixed layer functions to hold the magnetic flux of the other fixed layer. The magnetization direction of the intermediate second ferromagnetic layer can be freely rotated by the applied magnetic field. The electrical resistance of the first and second layers of the ferromagnetic layer and the second and third layers varies as a function of the cosine of the angle between the magnetization directions of the two ferromagnetic layers of the pair. When the magnetization direction of the intermediate free layer rotates from the direction substantially parallel to the magnetization direction of the first outer pinned layer to the direction substantially parallel to the magnetization direction of the third outer pinned layer, the resistance of the sensor is minimized. The value changes from the maximum value.
[0070]
Further, in a preferred example, a multilayer spin valve structure in which the magnetization directions in the two outer ferromagnetic layers are parallel and both are perpendicular to the magnetization directions in the intermediate ferromagnetic free layer can be obtained.
[0071]
For the film configuration of the spin valve type giant magnetoresistive effect film using FeMn as the antiferromagnetic film 16 of the reproducing head, current flows as FeMn (10 nm) / NiFe (5 nm) / Cu (2 nm) / NiFe (5 nm) 23. It consists of a magnetic domain control film which stabilizes the magnetic domain of an electrode and a giant magnetoresistive effect film. The reproduction track width is 0.8 μm. Furthermore, instead of the spin-valve giant magnetoresistive film 23, the tunnel junction giant magnetoresistive film has a structure of FeMn (10 nm) / NiFe (5 nm) / Co (3 nm) / Al.₂O_Three(1 nm) / Co (3 nm) / NiFe (5 nm) can be used.
[0072]
FIG. 10 is a cross-sectional view showing the manufacturing process of the recording / reproducing separated type magnetic head. The recording head portion comprises an upper magnetic core 9 and a lower magnetic core, a magnetic gap film 5, a conductor coil 7, a conductor coil 7, and insulating films 6 and 8 of upper and lower magnetic cores. It also serves as the lower magnetic core of the recording head. In FIG. 10 (a), the lower magnetic shield 1, the spin valve magnetoresistive film 2, the electrode and the magnetic domain control film 3, and the upper magnetic shield 4 serving as the lower magnetic core of the recording head are formed to form the reproducing head portion. The place where the gap film 5 is formed is shown. The reproduction track width is 0.8 μm, and a tunnel junction type giant magnetoresistive film may be used instead of the spin valve type. FIG. 10 (b) shows a photoresist mixed with melamine resin (Cymel 303, manufactured by Mitsui Seidek) in an amount of 25 wt% of the total resin amount and 5 wt% of 1,3,5-tris (bromoacetyl) benzene. After coating, a pattern is formed by sequentially irradiating with ultraviolet rays through a photomask and developing with a developer (DE-4: manufactured by Tokyo Ohka Kogyo Co., Ltd.), and baked in vacuum at 200 ° C. for 30 minutes to form the insulating film 6 It shows where it was formed. Of course, epoxy may be used instead of melamine, and the above-mentioned other substances such as 1,3,5-tris (dibromoacetyl) benzene may be used alone or in combination of two or more as an acid generator. The taper angle at the end of the insulating film 6 was about 45 degrees. Despite significantly lower temperature and shorter baking time than conventional conditions at 200 ° C. for 30 minutes, cross-linking of novolac resin and melamine resin has progressed due to the generation of acid catalyst due to thermal decomposition, resulting in higher molecular weight. Therefore, the adhesion was large, there was no defect such as pattern peeling, and the characteristics of the spin valve type giant magnetoresistive film were not deteriorated. FIG. 10C shows a state in which after the conductor coil 7 is formed, the insulating film 8 is formed by the same process as the insulating film 6, and the upper magnetic core 9 is formed thereon. The embedding of the resist in the gap between the coils and the flatness on the coil were not different from those of a normal resist, and a good recording head could be produced. The recording track width is 1.0 μm. At this time, the heat treatment conditions for the insulating film have been greatly relaxed from 250 ° C. for several hours to 200 ° C. for 30 minutes, so that a recording / reproducing separated type magnetic head can be manufactured without degrading the characteristics of the reproducing head. By installing this head, the surface recording density is 5 Gbit / in.²Magnetic disk device could be obtained.
[0073]
【The invention's effect】
By using a photoresist mixed with melamine or epoxy and a crosslinking accelerator as the insulating film, the curing process conditions can be relaxed while maintaining good adhesion. A resistance effect type magnetic head can be manufactured, and a high-performance magnetic disk apparatus can be manufactured.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a hard disk device according to the present invention.
FIG. 2 is a perspective view of a recording / reproducing separation type thin film magnetic head.
FIG. 3 is a perspective view of a negative pressure slider according to the present invention.
FIG. 4 is an overall view of a magnetic disk device according to the present invention.
FIG. 5 is a conceptual diagram of a disk array device according to the present invention.
FIG. 6 is a cross-sectional view of a spin valve head according to the present invention.
FIG. 7 is a cross-sectional view of a spin valve head according to the present invention.
FIG. 8 is a cross-sectional view of a spin valve head according to the present invention.
FIG. 9 is a cross-sectional view of an inductive recording head according to the present invention.
FIG. 10 is a manufacturing process diagram of a recording / reproducing separated thin film magnetic head according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,21 ... Lower magnetic shield, 2 ... Spin valve type magnetoresistive effect film, 3 ... Electrode and magnetic domain control film, 4 ... Upper magnetic shield combined with a lower magnetic core, 5 ... Gap film, 6, 8, 29 ... Insulating film, DESCRIPTION OF SYMBOLS 7 ... Conductor coil, 9 ... Upper magnetic core, 10 ... Magnetoresistive film, 12, 25 ... Magnetic domain control layer, 14 ... Electrode, 16, 40 ... Antiferromagnetic film, 18 ... First ferromagnetic film, 20, 34: Nonmagnetic film, 22, 24: Second ferromagnetic film, 23: Spin valve magnetic gap film, 26: Width of magnetoresistive film, 27: Magnetic gap film, 28: Permanent magnet film, 30: Orientation Control base film, 32... Electrode interval, 36 and 38... Third ferromagnetic film.

Claims (7)

In a recording / reproducing separated type head having an induction type recording head on a magnetoresistive effect type reproducing head,
The recording head is laminated on the lower magnetic film, one end is connected to the lower magnetic film, and the other end faces the lower magnetic film through a magnetic gap, and is magnetically coupled with the lower magnetic film. An upper magnetic core that forms a circuit; a conductor coil provided between the lower magnetic film and the upper magnetic core; and an insulating film that electrically insulates the lower magnetic film, the upper magnetic core, and the conductor coil from each other. Equipped,
The reproducing head has ferromagnetic first and second magnetic layers partitioned by a nonmagnetic layer, and the magnetization of the ferromagnetic first magnetic layer is zero when the applied magnetic field from the recording medium is zero. The direction is a direction perpendicular to the magnetization direction of the second layer,
The insulating film is obtained by curing a photoresist, a crosslinking agent, and a crosslinking accelerator of the photoresist and the crosslinking agent, the crosslinking agent is one or more of melamine and epoxy, and the crosslinking accelerator is , An organic compound that generates an acid by heating, and bromoacetylbenzene, p-bis (bromoacetyl) benzene, m-bis (bromoacetyl) benzene, 1,3,5-tris (bromoacetyl) benzene, Recording / reproducing separation characterized in that it is at least one of 3,5-tris (dibromoacetyl) benzene and 1,3,5-tris (chloroacetyl) benzene, and the photoresist is a novolak resin. Mold head. In a recording / reproducing separated type head having an induction type recording head formed on a magnetoresistive effect type reproducing head via a magnetic shield,
The recording head is stacked on the magnetic shield, one end is connected to the magnetic shield and the other end is opposed through a magnetic gap to form a magnetic circuit together with the magnetic shield, and the magnetic shield and the upper portion A conductor coil provided between the magnetic core and an insulating film that electrically insulates the magnetic shield, the upper magnetic core and the conductor coil from each other;
The read head has first and second ferromagnetic layers partitioned by a nonmagnetic layer, and an antiferromagnetic layer connected to one of the magnetic layers, and When the applied magnetic field is zero, the magnetization direction of the first magnetic layer of the ferromagnetic material is perpendicular to the magnetization direction of the second layer,
The insulating film is obtained by curing a photoresist, a crosslinking agent, and a crosslinking accelerator of the photoresist and the crosslinking agent, the crosslinking agent is one or more of melamine and epoxy, and the crosslinking accelerator is , An organic compound that generates an acid upon heating, and bromoacetylbenzene, p-bis (bromoacetyl) benzene, m-bis (bromoacetyl) benzene, 1,3,5-tris (bromoacetyl) benzene, Recording / reproducing separation characterized in that it is at least one of 3,5-tris (dibromoacetyl) benzene and 1,3,5-tris (chloroacetyl) benzene, and the photoresist is a novolak resin. Type thin film magnetic head. A recording / reproducing separated type in which a magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive reproducing head for reproducing the information written on the magnetic disk are integrally formed In a head disk assembly comprising a thin film magnetic head and drive means for rotating the disk,
It said recording head and / or reproducing head is made of a recording reproducing separate type head according to any one of claims 1-2, the head disk assembly, characterized in that it has a 3 Gbit / in ² or more recording densities. A recording / reproducing separated type in which a magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive reproducing head for reproducing the information written on the magnetic disk are integrally formed In a magnetic disk device having a plurality of head disk assemblies each including a thin film magnetic head and a driving means for rotating the disk,
A magnetic disk apparatus, wherein the recording head and / or reproducing head comprises the recording / reproducing separated type head according to any one of claims 1 to 3 . In a manufacturing method of a recording / reproducing separated type head in which an induction type recording head is formed on a magnetoresistive type reproducing head,
A reproducing head manufacturing process for forming the first and second magnetic layers of the ferromagnetic material partitioned by the nonmagnetic layer;
After the reproducing head manufacturing process, an upper magnetic core that forms a magnetic circuit together with the lower magnetic film with the other end facing the lower magnetic film and facing the other through a magnetic gap, the lower magnetic film and the upper magnetic core, An insulating film comprising a conductor coil provided between the photoresist, a photoresist, a crosslinking agent, and a crosslinking accelerator for electrically insulating the lower magnetic film, the upper magnetic core, and the conductor coil from each other. And a recording head manufacturing process for forming
The cross-linking agent is at least one of melamine and epoxy, and the cross-linking accelerator is an organic compound that generates an acid by heating, and bromoacetylbenzene, p-bis (bromoacetyl) benzene, m-bis ( At least one of bromoacetyl) benzene, 1,3,5-tris (bromoacetyl) benzene, 1,3,5-tris (dibromoacetyl) benzene, and 1,3,5-tris (chloroacetyl) benzene And the photoresist is a novolak resin , wherein the recording / reproducing separated type thin film magnetic head is manufactured. 6. The method of manufacturing a recording / reproducing separated type thin film magnetic head according to claim 5 , wherein an induction type recording head is formed on the reproducing head via a magnetic shield. 6. The method for manufacturing a recording / reproducing separated type thin film magnetic head according to claim 5 , wherein an antiferromagnetic layer is formed in contact with one of the first and second magnetic layers.

Images