JP2005209244A - Magnetic pole film for perpendicular magnetic recording, and thin film magnetic head including perpendicular magnetic recording element using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic recording magnetic pole film capable of suppressing pole erasing even when a magnetic pole width becomes narrower and simultaneously securing sufficient overwriting characteristics in a perpendicular magnetic recording system. <P>SOLUTION: The recording magnetic pole film 11 is formed by alternately stacking a film constituted of first and second magnetic layers 1 and 3 respectively made of Co50Fe50 and Co90Fe10 and stacked together, and a nonmagnetic layer 2 made of Ru. The second magnetic layer 3 is present between the first magnetic layer 1 and the nonmagnetic layer 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a magnetic pole film for perpendicular magnetic recording, a thin film magnetic head including a perpendicular magnetic recording element using the same, a head gimbal assembly, a head arm assembly, a head stack assembly, and a hard disk device.

  In order to increase the recording capacity of a hard disk drive, the magnetic pole width of the magnetic head must be narrowed to increase the track density, and at the same time, a material having a high saturation magnetic flux density must be used to improve the recording capability. Further, in order to improve the recording resolution, the coercive force of the magnetic recording medium must be increased. In order to ensure a sufficient overwrite characteristic for a magnetic recording medium having a high coercive force, it is necessary to use a material having a high saturation magnetic flux density such as a CoFe-based alloy, FeC, or FeN for the recording magnetic pole.

  The same applies to the perpendicular magnetic recording head. By using such a high saturation magnetic flux density material for the recording magnetic pole, the recording ability can be improved. However, in the perpendicular magnetic recording head, there is a problem that recorded information is erased by the recording magnetic pole other than during the recording operation. This problem is called “Paul Erase”.

  In a perpendicular magnetic recording head, a magnetic pole film used for recording is a soft magnetic material, and its hard axis is directed toward a medium facing surface (hereinafter referred to as “ABS”) as an air bearing surface facing the recording medium. Recording is performed on a magnetic recording medium by generating a recording magnetic field in the magnetization rotation mode. That is, by directing the hard magnetization axis to the ABS side, the residual magnetization on the ABS side is reduced as much as possible, so that no extra magnetic flux is generated on the magnetic recording medium side when the recording operation is not performed.

  However, when the recording density is improved, the tip of the recording magnetic pole becomes needle-like due to the narrowing of the track width, so that the domain wall trapping occurs due to the effect of shape anisotropy, and the domain structure becomes unstable and magnetized. The magnetic flux leaks to the magnetic recording medium side, and pole erase occurs.

  Further, in the perpendicular magnetic recording method, the leakage magnetic field from the magnetic recording medium is larger than that in the longitudinal magnetic recording method, and the perpendicular component easily causes the magnetization direction of the tip of the recording magnetic pole to be directed to the ABS side. It has become.

  Further, in the future improvement of recording density, when the width of the recording magnetic pole is further reduced, the effect of the shape anisotropy becomes more dominant, and the tip of the recording magnetic pole becomes larger on the magnetic recording medium side. Since it becomes easy to have remanent magnetization, it is expected that it will become a bigger problem.

Conventionally, as a means for stabilizing the magnetic domain structure in the recording magnetic pole, for example, Patent Document 1 discloses a soft magnetic multilayer film in which several to several tens of layers of different types of magnetic films and magnetic films and nonmagnetic films are stacked. ing. Further, as means for suppressing pole erasure, Patent Documents 2 to 4 describe devising the shape of the tip of the recording magnetic pole. However, Patent Document 1 does not show a sufficient means for stabilizing the magnetic domain structure and suppressing the pole erase when the recording magnetic pole width is narrowed. In Patent Documents 2 and 3, although means for suppressing pole erase are shown, means for suppressing pole erase when the recording magnetic pole width is further reduced are not sufficiently shown.
JP-A-5-29172 JP 2003-296906 A JP 2003-317212 A JP 2001-291212 A US Pat. No. 6,496,335 US Pat. No. 6,628,478

  Patent Documents 5 and 6 show that magnetic layers and nonmagnetic layers are alternately stacked, and that the magnetic layers are antiferromagnetically coupled to each other via the nonmagnetic layers. It is considered that the pole erase in the perpendicular magnetic recording head can be eliminated by using an antiferromagnetically coupled magnetic layer as the recording magnetic pole film.

  Ru, Rh, Cr, Cu, Au, Ag, Pt, Pd, or the like is used as a nonmagnetic layer for antiferromagnetically coupling magnetic layers. Further, as a material for the magnetic layer, a material having a high saturation magnetic flux density must be used in order to ensure overwrite characteristics. For example, a material such as a CoFe alloy, FeN, or FeC is used.

  A material having a high saturation magnetic flux density generally contains Fe as a main component, and Ru, Rh, Cu, Cr, etc., which are nonmagnetic layers for antiferromagnetically coupling the magnetic layers, are Fe layers of the magnetic layer. There is a problem that it is easy to diffuse. In addition, in the magnetic head process, after forming the recording magnetic pole, it may be necessary to go through a heat treatment step. When the heat treatment is performed, the diffusion becomes significant, the saturation magnetic flux density is lowered, and at the same time, exchange coupling May become weaker, the saturation magnetic field (Hs) may be extremely lowered, and pole erase may occur.

  Further, when the magnetic layers are antiferromagnetically coupled using a nonmagnetic material having a large exchange coupling energy such as Ru, the saturation magnetic field (Hs) becomes large, so that the recording magnetic pole is sufficiently saturated with the magnetic field generated from the recording coil. It may not be possible to obtain sufficient recording ability. In order to reduce the saturation magnetic field (Hs), it is conceivable to reduce the number of stacked layers and increase the thickness of the magnetic layer. However, in this method, the magnetic film thickness of the magnetic layer is increased, and a portion with weak antiferromagnetic coupling is inevitably generated, which may lead to occurrence of pole erase.

  Accordingly, an object of the present invention is to provide a magnetic recording magnetic pole film capable of suppressing pole erasure even when the magnetic pole width is narrowed in the perpendicular magnetic recording method, and a perpendicular magnetic recording head using the same, in view of the above-described problems of the prior art. There is to do.

  In order to achieve the above object, the present invention provides a recording magnetic pole film in which a magnetic layer and a nonmagnetic layer are alternately laminated, and the magnetic layer is antiferromagnetically coupled through the nonmagnetic layer, The magnetic layer is composed of a first magnetic layer and a second magnetic layer, and the second magnetic layer is disposed between the nonmagnetic layer and the first magnetic layer. Features.

  In the present invention, the first magnetic layer mainly comprising Fe and the nonmagnetic layer are not directly laminated, and the second magnetic layer not containing Fe as the main component is interposed between the nonmagnetic layer and the first magnetic layer. By disposing, the diffusion of the nonmagnetic material into the magnetic layer can be prevented.

  Furthermore, by adjusting the material, crystal structure, composition, and film thickness of the second magnetic layer, the saturation magnetic field (Hs) can be controlled without increasing without increasing the thickness of the magnetic layer. For example, the material of the second magnetic layer can be CoFe, NiFe, CoNi, Co, Ni, or the like. Further, nonmagnetic elements may be added to these materials. The second magnetic layer is preferably made of a material having a crystal structure other than the body-centered cubic structure. For example, as a material other than the body-centered cubic structure, CoFe, NiFe, or the like having a face-centered cubic structure can be applied. Further, Co or the like can be applied to a metal material having a hexagonal close-packed structure.

  The content of Fe in the second magnetic layer is preferably 20 (at.%) Or less. This is because if the Fe content exceeds 20 (at.%), Diffusion of Ru, Rh, Cr, Cu, Re, Au, Ag, Pt, Pd, or the like may become significant.

  In this case, the thickness of the second magnetic layer having an Fe content of 20 (at.%) Or less is preferably 1 nm or more and 5 nm or less. If the film thickness is less than 1 nm, the influence of diffusion of the nonmagnetic layer due to heat treatment cannot be sufficiently prevented. Even when heat treatment is not performed, if it is less than 1 nm, the saturation magnetic field Hs becomes too large to be controlled, and the recording ability may be insufficient. When the film thickness exceeds 5 nm, the material that does not contain Fe as the main component has a low saturation magnetic flux density, so the portion of the low saturation magnetic flux density that occupies the entire film increases and the saturation magnetic flux density of the entire recording magnetic pole decreases. Therefore, there is a possibility that the recording ability is insufficient.

  In the recording magnetic pole film as described above, the thickness of each first magnetic layer is preferably 10 nm or more and 70 nm or less. If the film thickness is less than 10 nm, even if the second magnetic layer is provided, the saturation magnetic field Hs becomes too large to be controlled, and the recording ability may be insufficient. When the film thickness exceeds 70 nm, there is a possibility that a weak portion of exchange coupling occurs in the middle portion of each first magnetic layer, and the saturation magnetic field Hs decreases and pole erasure occurs.

  The nonmagnetic layer is preferably made of any one of Ru, Rh, Cr, Cu, Re, Au, Ag, Pt, and Pd.

  In the recording magnetic pole film, the total difference in the magnetic film thicknesses of the first magnetic layer and the second magnetic layer is zero. As a result, the residual magnetic flux on the ABS side other than during the recording operation can be made zero, and the pole erase can be suppressed. The first magnetic layer in the recording magnetic pole film has a saturation magnetic flux density of 1.8 (T) or more.

  The present invention also provides a thin film magnetic head including a perpendicular magnetic recording element using the above-described magnetic pole film for perpendicular magnetic recording.

  The present invention also provides a head gimbal assembly having the above thin film magnetic head, a slider disposed so as to face the recording medium, and a suspension for elastically supporting the slider.

  The present invention also provides a head arm assembly having the head gimbal assembly described above and an arm to which the head gimbal assembly is attached.

  The present invention also provides a head stack assembly having a carriage having a plurality of arms and the above-described head gimbal assembly attached to each arm of the carriage.

  The present invention also includes a slider that includes the thin film magnetic head described above and is disposed so as to face a disk-shaped recording medium that is driven to rotate, and a positioning device that supports the slider and positions the recording medium relative to the recording medium. A hard disk device is provided.

  According to the present invention, since magnetic layers and nonmagnetic layers are alternately stacked, no residual magnetic flux is generated due to the effect of antiferromagnetic coupling even when the track width is narrowed. Can be suppressed. Further, the magnetic layer is constituted by the first magnetic layer and the second magnetic layer, and the second magnetic layer having a low Fe content is disposed between the first magnetic layer and the nonmagnetic layer, A nonmagnetic layer such as Ru or Cr is not diffused into the first magnetic layer mainly composed of Fe. For this reason, the saturation magnetic flux density does not decrease, and sufficient recording ability can be obtained.

  Furthermore, by adjusting the material, crystal structure, composition, and film thickness of the second magnetic layer, the saturation magnetic field (Hs) can be controlled without increasing without increasing the thickness of the first magnetic layer. Can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a sectional view of a recording magnetic pole film according to an embodiment of the present invention.

  As shown in this figure, the magnetic pole film is formed by alternately laminating a magnetic layer composed of a first magnetic layer 1 and a second magnetic layer 3 and a nonmagnetic layer 2.

  Between the first magnetic layer 1 having a thickness of 60 nm made of a composition material (hereinafter referred to as Co50Fe50) having Co of 50 (at.%) And Fe of 50 (at.%), Non-made of Ru having a thickness of 0.8 nm. A magnetic layer 2 is present to antiferromagnetically bond the first magnetic layers 1 to each other, and between the first magnetic layer 1 and the nonmagnetic layer 2, Co is 90 (at.%) And Fe. Is a 1 nm thick second magnetic layer 3 made of a composition material of 10 (at.%) (Hereinafter referred to as Co90Fe10).

  Depending on the process of the thin film magnetic head, the heat treatment may or may not be performed after the recording magnetic pole film is formed. When the heat treatment is performed without providing the second magnetic layer, the nonmagnetic layer diffuses into the first magnetic layer by the heat treatment, the antiferromagnetic coupling becomes weak, and pole erase occurs. Further, when the heat treatment is not performed without providing the second magnetic layer, the saturation magnetic field Hs becomes too large due to the nature of the exchange coupling film. For this reason, the magnetomotive force of the coil of the magnetic head cannot be sufficiently magnetized when the recording magnetic pole film of the present invention is used, and the recording ability is insufficient.

  Therefore, the stacked films as shown in FIG. In the recording magnetic pole film 11, the magnetic layer and the nonmagnetic layer 2 composed of the first magnetic layer 1 containing Fe as a main component and the second magnetic layer 3 not containing Fe as shown in FIG. By laminating, since the residual magnetic flux does not occur due to the effect of antiferromagnetic coupling even when the track width is narrowed, pole erase can be suppressed. Furthermore, by disposing the second magnetic layer 3 containing no Fe as a main component between the first magnetic layer 1 and the nonmagnetic layer 2, the nonmagnetic layer 2 such as Ru or Cr is made of Fe. Since the magnetic layer 1 is not diffused, the saturation magnetic flux density does not decrease and sufficient recording capability can be obtained.

  2 is a plan view showing an embodiment of a perpendicular magnetic recording element according to the present invention, FIG. 3 is a cross-sectional view taken along the line CC of FIG. 2, and FIG. 4 is a perpendicular magnetic recording element shown in FIGS. It is a figure which shows the end surface by the side of ABS. The perpendicular magnetic recording element according to the present invention can be mainly used in a magnetic head of a hard disk device, but is not limited to this and can be widely applied in the magnetic recording field.

  2 to 4, the recording element portion W is magnetically shielded by the first shield film 21 and the second shield film 22 that are arranged at intervals. The white display portion that fills around the recording element portion W, the first shield film 21, and the second shield film 22 is, for example, an insulating film made of a metal oxide or an organic insulating material. The perpendicular magnetic recording element has a medium facing surface 10 facing the magnetic recording medium. The medium facing surface 10 is used as an air bearing surface (ABS) in the thin film magnetic head.

  The recording element portion W includes a recording magnetic pole film 11, an auxiliary magnetic pole film 12, a return yoke film 13, a coil film 14, and a connecting portion 15.

  The recording magnetic pole film 11 is a recording magnetic pole film made of a multilayer film having the structure shown in FIG. 1. As shown in FIG. 2, the recording magnetic pole film 11 has a magnetic pole end (pole portion) P1 with a very narrow tip. The yoke portion YK extends to the rear. The tip end surface of the magnetic pole tip P1 is on the surface of the medium facing surface 10. The auxiliary magnetic pole film 12 is provided adjacent to the yoke portion YK of the recording magnetic pole film 11, and concentrates the magnetic flux on the magnetic pole end P1 without causing magnetic saturation in the yoke portion YK.

  The return yoke film 13 is disposed at a distance from the recording magnetic pole film 11 and the auxiliary magnetic pole film 12 and is coupled to the auxiliary magnetic pole film 12 by the connecting portion 15 on the rear side with respect to the medium facing surface 10. . The magnetic flux emitted from the magnetic pole end P1 of the recording magnetic pole film 11 is collected on the return yoke film 13 that spreads widely.

  The coil film 14 is disposed between the auxiliary magnetic pole film 12 and the return yoke film 13 so as to spiral around the coupling portion 14. In addition to the spiral arrangement shown in the figure, the coil film 14 may take other forms and structures such as a helical shape that circulates around the return yoke film 13.

  Depending on the process of the thin film magnetic head, the heat treatment may or may not be performed after the recording magnetic pole film is formed. When the heat treatment is performed without providing the second magnetic layer, the nonmagnetic layer diffuses into the first magnetic layer by the heat treatment, the antiferromagnetic coupling becomes weak, and pole erase occurs. Further, when the heat treatment is not performed without providing the second magnetic layer, the saturation magnetic field Hs becomes too large due to the nature of the exchange coupling film. For this reason, the magnetomotive force of the coil of the magnetic head cannot be sufficiently magnetized when the recording magnetic pole film of the present invention is used, and the recording ability is insufficient.

  Therefore, the stacked films as shown in FIG. In the recording magnetic pole film 11, the magnetic layer and the nonmagnetic layer 2 composed of the first magnetic layer 1 containing Fe as a main component and the second magnetic layer 3 not containing Fe as shown in FIG. By laminating, since the residual magnetic flux does not occur due to the effect of antiferromagnetic coupling even when the track width is narrowed, pole erase can be suppressed. Further, by disposing the second magnetic layer 3 not containing Fe as a main component between the first magnetic layer 1 and the nonmagnetic layer 2, the nonmagnetic layer 2 such as Ru or Cr contains Fe as a main component. Since it is not diffused into the first magnetic layer 1, the saturation magnetic flux density does not decrease and a sufficient recording capability is obtained.

  FIG. 5 is a diagram for explaining the operation when perpendicular magnetic recording is performed on a magnetic recording medium using the above-described perpendicular magnetic recording element. In the illustrated perpendicular magnetic recording element, the recording magnetic pole film 11 supplies a write current to the coil film 14 to generate a magnetic flux in the Y direction, and the recording magnetic field Fφ generated thereby causes the recording magnetic film 11 to be applied to the perpendicular magnetic recording medium S. It is recorded.

  The perpendicular magnetic recording medium S has a structure in which a soft magnetic layer 32 is provided on a substrate 33 and a recording layer 31 is provided thereon. The recording magnetic field Fφ emitted from the magnetic pole tip P1 of the recording magnetic pole film 11 passes through the recording layer 31 and is magnetized in a direction perpendicular to the film surface, and further passes through the soft magnetic layer 32 and is returned by the return yoke film 13. Absorbed.

  Next, a thin film magnetic head according to the present invention will be described.

  6 is a plan view showing a surface of the thin film magnetic head according to the present invention facing the recording medium, FIG. 7 is a sectional view taken along line XX of FIG. 6, and FIG. 8 is a view of the thin film magnetic head shown in FIGS. It is an expanded sectional view of an element portion.

  A thin film magnetic head 400 shown in FIGS. 6 to 8 is called a head slider having a slider base 5 and an electromagnetic transducer including a recording element portion W and a reproducing element portion R. The recording element portion W is a perpendicular magnetic recording element using the recording magnetic pole film shown in FIG. 1, and the reproducing element portion (reading element portion) R uses a GMR element 30 or TMR element using a spin valve film. To do.

The slider base 5 is made of a ceramic material such as AlTiC (Al ₂ O ₃ —TiC), for example, and has a geometric shape for controlling the flying characteristics on the medium facing surface. As a representative example of such a geometric shape, in FIGS. 6 and 7, the first step portion 51, the second step portion 52, the third step portion 53, and the fourth step are provided on the base surface 50 of the slider base 5. The example provided with the step part 54 and the fifth step part 55 is shown. The basal plane 50 serves as a negative pressure generating portion with respect to the air flow direction indicated by the arrow A, and the second step portion 52 and the third step portion 53 constitute a stepped air bearing rising from the first step portion 51. . The fourth step portion 54 rises in a step shape from the base surface 50, and the fifth step portion 55 rises in a step shape from the fourth step portion 54.

  The electromagnetic conversion element including the recording element portion W and the reproducing element portion R is provided in the fifth step portion 55. Further, the surfaces of the second step portion 52 and the third step portion 53 become the medium facing surface 10 as shown in FIG.

Referring to FIG. 8, an insulating film 501 is provided on the end surface of the slider base 5. The insulating film 501 is made of an insulating material such as alumina (Al ₂ O ₃ ) or SiO ₂ and has a thickness of 1 to 5 μm.

  The recording element portion W is the perpendicular magnetic recording element according to the present invention shown in FIGS. 2 to 4, and the magnetic pole tip P 1 faces the medium facing surface 10. The recording element portion W is disposed in the vicinity of the reproducing element portion R and is covered with a protective film 43.

  As already described with reference to FIGS. 2 to 4, the perpendicular magnetic recording element includes the recording magnetic pole film 11, the auxiliary magnetic pole film 12, the return yoke film 13, the coil film 14, and the first shield. A film 21 and a second shield film 22 are included. Here, the return yoke film 13 also has the function of the first shield film.

  The end face of the magnetic pole end P 1 of the recording magnetic pole film 11 is located on the medium facing surface 10. The coil film 14 is provided in the insulating film 44 while being supported by the insulating film 42. The GMR element 30 is disposed between the return yoke film 13 constituting the recording element portion W and the slider base 5.

  In the thin film magnetic head according to the present invention, since the recording element portion W described with reference to FIGS. 2 to 4 is used as a writing element, pole erasure, which is a problem peculiar to perpendicular magnetic recording, can be suppressed, and sufficient recording ability can be obtained. can get.

  FIG. 9 is a longitudinal sectional view showing another embodiment of the thin film magnetic head according to the present invention. 9, the same reference numerals are used for the same components as those shown in FIG.

  In the example shown in this figure, the second shield film 22 is formed on an insulating film 44 that insulates the periphery of the coil film 14. Here, the second shield film also has the function of the return yoke film 13. The non-hatched portion in the figure is an insulating film formed of an inorganic insulating material.

  FIG. 10 is a longitudinal sectional view showing still another embodiment of the thin film magnetic head according to the present invention. 10, the same reference numerals are used for the same components as those shown in FIGS.

  In the example shown in this figure, the second shield film 22 is formed on an insulating film 44 that insulates the periphery of the coil film 14, and has an auxiliary magnetic film 23 at the tip. Here, the second shield film also has the function of the return yoke film 13.

  FIG. 11 is a longitudinal sectional view showing still another embodiment of the thin film magnetic head according to the present invention, and FIG. 12 is a view as seen from the ABS side of the thin film magnetic head shown in FIG. 11, the same reference numerals are used for the same components as those shown in FIGS. In the examples shown in these drawings, the auxiliary magnetic pole film 12 is extended to a position slightly retracted from the magnetic pole tip P1 of the recording magnetic pole film 11, and a second parallel to the medium facing surface 10 is provided around the magnetic pole tip P1. A shield film 22 is provided. An insulating film 43 is interposed between the second shield film 22 and the recording magnetic pole film 11 and the auxiliary magnetic pole film 12. Here, the second shield film also has the function of the return yoke film 13.

  In the case of the embodiments shown in FIGS. 8 to 12, since the recording element portion W described with reference to FIGS. 2 to 4 is used as a writing element, pole erasure that is a problem peculiar to perpendicular magnetic recording can be suppressed. Sufficient recording ability can be obtained.

  Next, a head gimbal assembly and a hard disk device to which the thin film magnetic head of the present invention can be applied will be described.

  Referring to FIGS. 13 and 14, the head gimbal assembly 31 includes a floating thin film magnetic head 400 called a head slider, and a suspension 32 that elastically supports the thin film magnetic head 400. The suspension 32 is a leaf spring-shaped load beam 33 formed of, for example, stainless steel, and is provided at one end of the load beam 33 and a thin film magnetic head 400 is bonded to the flexure to give the thin film magnetic head 400 an appropriate degree of freedom. 34 and a base plate 35 provided at the other end of the load beam 33. The base plate 35 is attached to an arm 36 of an actuator for moving the thin film magnetic head 400 in the track crossing direction X of the hard disk 45. The actuator includes an arm 36 and a voice coil motor that drives the arm 36. A portion of the flexure 34 where the thin film magnetic head 400 is attached is provided with a gimbal portion for keeping the posture of the thin film magnetic head 400 constant.

  The head gimbal assembly 31 is attached to the arm 36 of the actuator. A structure in which the head gimbal assembly 31 is attached to one arm 36 is called a head arm assembly. Further, the head gimbal assembly 31 attached to each arm of a carriage having a plurality of arms is called a head stack assembly.

  FIG. 13 shows an example of a head arm assembly. In this head arm assembly, a head gimbal assembly 31 is attached to one end of the arm 36. A coil 37 serving as a part of the voice coil motor is attached to the other end of the arm 36. A bearing portion 38 attached to a shaft 39 for rotatably supporting the arm 36 is provided at an intermediate portion of the arm 36.

  Next, an example of a head stack assembly and an example of a hard disk device will be described with reference to FIGS. FIG. 14 is an explanatory view showing a main part of the hard disk device, and FIG. 15 is a plan view of the hard disk device.

  The head stack assembly 40 includes a carriage 41 having a plurality of arms 42. A plurality of head gimbal assemblies 31 are attached to the plurality of arms 42 so as to be arranged in the vertical direction at intervals. A coil 47 that is a part of the voice coil motor is attached to the carriage 41 on the side opposite to the arm 42. The head stack assembly 40 is incorporated in a hard disk device. The hard disk device has a plurality of hard disks 45 attached to a spindle motor 44. For each hard disk 45, two thin film magnetic heads 400 are arranged so as to face each other with the hard disk 45 interposed therebetween. Further, the voice coil motor has permanent magnets 46 arranged at positions facing each other with the coil 47 of the head stack assembly 40 interposed therebetween.

  The head stack assembly 40 and the actuator excluding the thin film magnetic head 400 support the thin film magnetic head 400 and position it relative to the hard disk 45.

  In the hard disk device of this embodiment, the thin film magnetic head 400 is moved with respect to the hard disk 45 by moving the thin film magnetic head 400 in the track crossing direction of the hard disk 45 by the actuator. The thin film magnetic head 400 records information on the hard disk 45 by a recording element unit built in the thin film magnetic head 400, and information recorded on the hard disk 45 by a reproducing element unit built in the thin film magnetic head 400. Play.

  The above-described head gimbal assembly and hard disk drive to which the thin film magnetic head of the present invention is applied have excellent resistance to environmental temperature changes and impacts.

  Next, the evaluation results of the magnetic recording magnetic pole film of the present invention and the perpendicular magnetic recording head using this as a recording magnetic pole will be described with reference to Table 1.

  Table 1 shows the configuration conditions and experimental results of the magnetic pole films of Examples 1 to 14 and Comparative Examples 1 to 10.

"experimental method"
The thin film was formed by using a DC sputtering method to deposit a magnetic layer and a nonmagnetic layer. The magnetic layer (first magnetic layer) includes Co50Fe50 or a composition material (hereinafter referred to as Co30Fe70) having Co of 30 (at.%) And Fe of 70 (at.%), A nonmagnetic layer (nonmagnetic intermediate layer) ) Was Ru or Cr. In the second magnetic layer, a composition material (hereinafter referred to as Ni80Fe20) with Ni of 80 (at.%) And Fe of 20 (at.%), Or Co of 90 (at.%) And Fe of 10 (at. .) Composition material (hereinafter referred to as Co90Fe10) or Co was used to form a film in a magnetic field. As described in Examples 1 to 18 and Comparative Examples 1 to 7 in Table 1, the number of stacked layers and the thicknesses of the first magnetic layer, the second magnetic layer, and the nonmagnetic layer (nonmagnetic intermediate layer) were changed. When heat treatment was performed, it was kept in vacuum at 250 ° C. for 3 hours, and then naturally cooled.

  A vibrating sample magnetometer (VSM) was used for measurement of the magnetic properties. A surface roughness meter was used for measuring the film thickness.

  An Auger electron spectrometer was used to observe the diffusion of the nonmagnetic layer.

  Further, the films having the constitutional conditions described in Examples 1 to 14 in Table 1 were mounted on the perpendicular magnetic recording head as recording magnetic poles, and pole erase was evaluated. For comparison with the examples as in Comparative Examples 1 to 10 in Table 1, the same evaluation was performed for the recording magnetic pole in which the magnetic layer and the nonmagnetic layer of Ru were alternately laminated and having no second magnetic layer. went. A spin stand (Agilent: E5022) was used for evaluation of occurrence of pole erase, and a perpendicular magnetic recording medium having a coercive force of 3300 [Oe] was used as an evaluation medium.

  Dividing one round into 75 sectors for the evaluation medium, recording a high-frequency signal once in all sectors, and then feeding a low-frequency signal to the head of each sector at 1 / 30th of the sector length Overwriting was performed, the amplitude of the high-frequency signal was measured, and this was repeated 100 times.

  At this time, the tracks adjacent to the recording track were erased by DC +, DC− and AC over 30 μm on both sides.

  Under each condition, a signal whose amplitude of the output signal of the high frequency signal decreased by 10% or more was regarded as having pole erase.

"Experimental result"
In Examples 1 to 12, the crystal structure of the second magnetic layer is a face-centered cubic structure (fcc), and in Examples 13 and 14, the crystal structure of the second magnetic layer is a hexagonal close-packed structure (hcp).

  In Example 1, the total thickness (nm) of the recording magnetic pole film is 249.4 (nm), the number of stacked layers is 4, the thickness of the first magnetic layer made of Co50Fe50 is 60 nm, and the thickness of the second magnetic layer made of Co90Fe10. The thickness of the nonmagnetic intermediate layer made of Ru is 0.8 nm and heat treatment is not performed.

  In this case, the ABS direction saturation magnetic field Hs (A / m) is 487 × 79.6 (A / m), the saturation magnetic flux density Bs (T) is 2.2 (T), and the ABS direction residual magnetic flux density Br (T) is 0 (T) and no pole erase occurred.

  In Example 2, the total thickness (nm) of the recording magnetic pole film, the number of stacked layers, the thickness of the first magnetic layer made of Co50Fe50, the thickness of the second magnetic layer made of Co90Fe10, and the thickness of the nonmagnetic intermediate layer made of Ru were carried out. Same as Example 1, but heat treatment was performed.

  In this case, no pole erase occurred. Further, even if the heat treatment is performed, since there is the second magnetic layer, the ABS direction saturation magnetic field Hs (A / m) and the saturation magnetic flux density Bs (T) do not decrease as compared with the first embodiment.

  In Example 3, the total thickness (nm) of the recording magnetic pole film was 252.4 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 59 nm, and the thickness of the second magnetic layer made of Co90Fe10. The thickness of the nonmagnetic intermediate layer made of Ru is 0.8 nm, and no heat treatment is performed.

  In this case, the ABS direction saturation magnetic field Hs (A / m) is 432 × 79.6 (A / m), the saturation magnetic flux density Bs (T) is 2.1 (T), and the ABS direction residual magnetic flux density Br (T) is 0 (T) and no pole erase occurred. Further, the value of the ABS saturation magnetic field Hs could be changed by increasing the thickness of the second magnetic layer with respect to Examples 1 and 2.

  In Example 4, the total thickness (nm) of the recording magnetic pole film, the number of stacked layers, the thickness of the first magnetic layer made of Co50Fe50, the thickness of the second magnetic layer made of Co90Fe10, and the thickness of the nonmagnetic intermediate layer made of Ru were carried out. Same as Example 3, but heat treatment was performed.

  In this case, no pole erase occurred. Further, even when the heat treatment is performed, since the second magnetic layer is present, the ABS-direction saturation magnetic field Hs (A / m) and the saturation magnetic flux density Bs (T) do not decrease as compared with the third embodiment.

  In Example 5, the total thickness (nm) of the recording magnetic pole film is 249 (nm), the number of stacked layers is 6, the thickness of the first magnetic layer made of Co50Fe50 is 39 nm, and the thickness of the second magnetic layer made of Co90Fe10 is 1 nm. The thickness of the nonmagnetic intermediate layer made of Ru is 0.8 nm, and no heat treatment is performed.

  In this case, the ABS direction saturation magnetic field Hs (A / m) is 619 × 79.6 (A / m), and the number of stacked layers is increased with respect to Examples 1 to 4, and the thickness of the first magnetic layer is reduced. As a result, the saturation magnetic field Hs (A / m) in the ABS direction increased.

  In Example 6, the total thickness (nm) of the recording magnetic pole film is 249 (nm), the number of stacked layers is 6, the thickness of the first magnetic layer made of Co50Fe50 is 39 nm, and the thickness of the second magnetic layer made of Co90Fe10 is 1 nm. The thickness of the nonmagnetic intermediate layer made of Ru was 0.8 nm, and the heat treatment was performed.

  In this case, no pole erase occurred. Further, even when the heat treatment is performed, since there is the second magnetic layer, the ABS direction saturation magnetic field Hs (A / m) and the saturation magnetic flux density Bs (T) do not decrease as compared with the fifth embodiment.

  In Example 7, the total thickness (nm) of the recording magnetic pole film was 252.6 (nm), the number of stacked layers was 8, the thickness of the first magnetic layer made of Co50Fe50 was 29 nm, and the thickness of the second magnetic layer made of Co90Fe10. The thickness of the nonmagnetic intermediate layer made of Ru is 0.8 nm and heat treatment is not performed.

  In this case, the ABS direction saturation magnetic field Hs (A / m) is 765 × 79.6 (A / m), and the number of stacked layers is further increased with respect to Examples 5 and 6, and the thickness of the first magnetic layer is reduced. As a result, the saturation magnetic field Hs (A / m) in the ABS direction increased.

  In Example 8, the total thickness (nm) of the recording magnetic pole film was 252.6 (nm), the number of stacked layers was 8, the thickness of the first magnetic layer made of Co50Fe50 was 29 nm, and the thickness of the second magnetic layer made of Co90Fe10. The thickness of the nonmagnetic intermediate layer made of Ru was 0.8 nm and the heat treatment was performed.

  In this case, no pole erase occurred. Further, even when the heat treatment is performed, since there is the second magnetic layer, the ABS direction saturation magnetic field Hs (A / m) and the saturation magnetic flux density Bs (T) do not decrease as compared with the seventh embodiment.

  In Example 9, the total thickness (nm) of the recording magnetic pole film was 249.7 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co30Fe70 was 60 nm, and the thickness of the second magnetic layer made of Co90Fe10. The thickness of the nonmagnetic intermediate layer made of Cr is 0.9 nm, and no heat treatment is performed.

  In this case, the film thickness of each layer is the same as in Example 1, but the material of the magnetic layer and the material of the nonmagnetic intermediate layer are changed. This material did not cause pole erase.

  In Example 10, the total thickness (nm) of the recording magnetic pole film was 249.7 (nm), the number of layers was 4, Co was 30 (at.%), And Fe was 70 (at.%). The thickness of the first magnetic layer made of Co30Fe70 was 60 nm, the thickness of the second magnetic layer made of Co90Fe10 was 1 nm, and the thickness of the nonmagnetic intermediate layer made of Cr was 0.9 nm.

  In this case, the material of the magnetic layer and the nonmagnetic intermediate layer are changed, but pole erasure has not occurred, and it can be seen that the second magnetic layer functions even if heat treatment is performed at this time. .

  In Example 11, the total thickness (nm) of the recording magnetic pole film was 248.2 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 60 nm, and the thickness of the second magnetic layer made of Ni80Fe20. The thickness of the nonmagnetic intermediate layer made of Ru is 0.4 nm and heat treatment is not performed.

  In this case, the thickness of each layer is the same as that of Example 1, but the thickness of the nonmagnetic intermediate layer and the second magnetic layer material are changed. This material did not cause pole erase.

  In Example 12, the total thickness (nm) of the recording magnetic pole film was 248.2 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 60 nm, and the thickness of the second magnetic layer made of Ni80Fe20. The thickness of the nonmagnetic intermediate layer made of Ru was 0.4 nm and the heat treatment was performed.

  In this case, although the thickness of the nonmagnetic intermediate layer and the second magnetic layer material are changed, no pole erase has occurred, and the second magnetic layer functions even if heat treatment is performed at this time. I understand that.

  In Example 13, the total thickness (nm) of the recording magnetic pole film was 249.4 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 60 nm, and the thickness of the second magnetic layer made of Co. The thickness of the nonmagnetic intermediate layer made of Ru is 0.8 nm and heat treatment is not performed.

  In this case, the thickness of each layer is the same as that of Example 1, but the second magnetic layer material is changed. This material did not cause pole erase.

  In Example 14, the total thickness (nm) of the recording magnetic pole film was 249.4 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 60 nm, and the thickness of the second magnetic layer made of Co. The thickness of the nonmagnetic intermediate layer made of Ru was 0.8 nm and the heat treatment was performed.

  In this case, although the second magnetic layer material is changed, no pole erase has occurred, and it can be seen that the second magnetic layer functions even if heat treatment is performed at this time.

  Next, Comparative Examples 1 to 10 will be described.

  In Comparative Example 1, the total thickness (nm) of the recording magnetic pole film is 242.4 (nm), the number of stacked layers is 4, the thickness of the first magnetic layer made of Co50Fe50 is 60 nm, and the thickness of the nonmagnetic intermediate layer made of Ru. The heat treatment was performed at 0.8 nm.

  In this case, since the second magnetic layer is not used, the ABS saturation magnetic field Hs is greatly reduced to 55 × 79.6 (A / m) by heat treatment, and pole erasure occurs. Further, the saturation magnetic flux density Bs (T) is 2.0, which is lower than that of the example.

  In Comparative Example 2, the total thickness (nm) of the recording magnetic pole film is 242.4 (nm), the number of stacked layers is 4, the thickness of the first magnetic layer made of Co50Fe50 is 60 nm, and the thickness of the nonmagnetic intermediate layer made of Ru is made. The thickness is set to 0.8 nm and no heat treatment is performed.

  In this case, pole erasure did not occur because no heat treatment was performed, but because the second magnetic layer was not used, the ABS saturation magnetic field Hs increased to 954 × 79.6 (A / m). Therefore, the magnetomotive force of the coil of the magnetic head is inappropriate for use as a recording magnetic pole film.

  In Comparative Example 3, the total thickness (nm) of the recording magnetic pole film was 325.6 (nm), the number of stacked layers was 8, the thickness of the first magnetic layer made of Co50Fe50 was 40 nm, and the thickness of the nonmagnetic intermediate layer made of Ru. The thickness is set to 0.8 nm and no heat treatment is performed.

  In this case, no pole erasure occurred because no heat treatment was performed, but because the second magnetic layer was not used, the ABS saturation magnetic field Hs increased to 2500 × 79.6 (A / m). Therefore, the magnetomotive force of the coil of the magnetic head is inappropriate for use as a recording magnetic pole film.

  In Comparative Example 4, the total thickness (nm) of the recording magnetic pole film is 242.4 (nm), the number of stacked layers is 4, the thickness of the first magnetic layer made of Co30Fe70 is 60 nm, and the thickness of the nonmagnetic intermediate layer made of Cr is made. The heat treatment was performed at 0.9 nm.

  In this case, since the second magnetic layer is not used, the ABS direction saturation magnetic field Hs is greatly reduced to 21 × 79.6 (A / m) by performing heat treatment, and pole erasure occurs. Further, the saturation magnetic flux density Bs (T) is 2.0, which is lower than that of the example.

  In Comparative Example 5, the recording magnetic pole film was a single-layer film of the first magnetic layer made of Co30Fe70, the thickness was 250 nm, and heat treatment was performed.

  In this case, the ABS direction saturation magnetic field Hs is reduced to 12 × 79.6 (A / m) due to the influence of the diffusion of the nonmagnetic layer by the heat treatment, and the residual magnetic flux is generated to generate the pole erase.

  In Comparative Example 6, the total thickness (nm) of the recording magnetic pole film was 249.4 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 60 nm, Ni was 75 (at.%), And Fe. The thickness of the second magnetic layer made of a composition material of 25 (at.%) (Hereinafter referred to as Ni75Fe25) was 1 nm, and the thickness of the nonmagnetic intermediate layer made of Ru was 0.8 nm.

  In this case, the ABS saturation magnetic field Hs is lowered to 87 × 79.6 (A / m) due to the influence of the diffusion of the nonmagnetic layer due to the heat treatment, and the residual magnetic flux is generated and the pole erase is generated.

  In Comparative Example 7, the total thickness (nm) of the recording magnetic pole film was 245.6 (nm), the number of stacked layers was 28, the thickness of the first magnetic layer made of Co50Fe50 was 8 nm, and the thickness of the nonmagnetic intermediate layer made of Ru. The thickness is set to 0.8 nm and no heat treatment is performed.

  In this case, although pole erasure has not occurred, since the first magnetic layer is thin, the ABS saturation magnetic field Hs becomes too large at 4521 × 79.6 (A / m), and the coil of the magnetic head This magnetomotive force is inappropriate for use as a recording magnetic pole film.

  In Comparative Example 8, the total thickness (nm) of the recording magnetic pole film was 302.4 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 75 nm, and the thickness of the nonmagnetic intermediate layer made of Ru. The thickness is set to 0.8 nm and no heat treatment is performed.

  In this case, since the thickness of the first magnetic layer is thick, the exchange coupling magnetic field is weak, the ABS residual magnetic flux density Br is generated, and pole erasure occurs.

  In Comparative Example 9, the total thickness (nm) of the recording magnetic pole film was 248.4 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 51 nm, and the thickness of the second magnetic layer made of Ni80Fe20. Was 6 nm, the thickness of the nonmagnetic intermediate layer made of Ru was 0.8 nm, and heat treatment was performed.

  In this case, since the thickness of the second magnetic layer is thick, the saturation magnetic flux density Bs (T) of the entire recording magnetic pole film is reduced to 1.7 (T).

  In Comparative Example 10, the total thickness (nm) of the recording magnetic pole film was 245.9 (nm), the number of stacked layers was 4, the thickness of the first magnetic layer made of Co50Fe50 was 60 nm, and the thickness of the second magnetic layer made of Co90Fe10. Is 0.5 nm, and no heat treatment is performed.

  In this case, since the second magnetic layer is thin, the ABS saturation magnetic field Hs becomes too large at 924 × 79.6 (A / m), and the magnetomotive force of the coil of the magnetic head is used as the recording magnetic pole film. Inappropriate for

  Further, when the thickness of the nonmagnetic layer in the first magnetic layer (the thickness of the diffusion layer) is observed, as shown in Table 1, Examples 2, 10, and 11 in which the second magnetic layer is provided are Although diffusion of the nonmagnetic layer into the magnetic layer was not observed, Comparative Examples 1, 4 and 6 in which the second magnetic layer was not provided diffused greatly.

2 is a cross-sectional view showing a film structure of a recording magnetic pole for a perpendicular magnetic head according to an embodiment of the present invention. FIG. It is a top view which shows one Example of the element for perpendicular magnetic recording based on this invention. It is CC sectional view taken on the line of FIG. It is a figure which shows the end surface by the side of the ABS of the element for perpendicular magnetic recording shown in FIG. 2 and FIG. It is a figure explaining the operation | movement at the time of performing perpendicular magnetic recording on a magnetic recording medium using the element for perpendicular magnetic recording containing the recording magnetic pole film of this invention. It is a top view which shows the surface facing the recording medium of the thin film magnetic head which concerns on this invention. It is the XX sectional view taken on the line of FIG. FIG. 8 is an enlarged cross-sectional view of an element portion of the thin film magnetic head shown in FIGS. 6 and 7. It is a longitudinal cross-sectional view which shows another Example of the thin film magnetic head based on this invention. It is a longitudinal cross-sectional view which shows another Example of the thin film magnetic head based on this invention. It is a longitudinal cross-sectional view which shows another Example of the thin film magnetic head based on this invention. It is the figure seen from the ABS side of the thin film magnetic head shown in FIG. It is a perspective view which shows the head gimbal assembly provided with the thin film magnetic head which concerns on this invention. FIG. 14 is a perspective view showing a head arm assembly including the head gimbal assembly shown in FIG. 13. FIG. 15 is a perspective view showing a hard disk device including the head arm assembly shown in FIG. 14.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st magnetic layer 2 Nonmagnetic layer 3 2nd magnetic layer 5 Slider base | substrate 10 Medium opposing surface 11 Recording magnetic pole film 12 Auxiliary magnetic pole film 13 Return yoke film 14 Coil film 15 Connection part 21,22 1st shield film 23 Auxiliary magnetic film 28 Shield layer 30 GMR element 31 Recording layer 32 Soft magnetic layer 33 Substrate 42, 44 Insulating film 43 Protective film 50 Base surface 51 First step portion 52 Second step portion 53 Third step portion 54 Fourth Step portion 55 Fifth step portion 501 Insulating film

Claims (14)

A magnetic pole film in which magnetic layers and nonmagnetic layers are alternately stacked, and the magnetic layer is antiferromagnetically coupled via the nonmagnetic layer,
The magnetic layer comprises a first magnetic layer and a second magnetic layer,
A magnetic pole film for perpendicular magnetic recording, wherein the second magnetic layer is disposed between the nonmagnetic layer and the first magnetic layer.   2. The magnetic pole film for perpendicular magnetic recording according to claim 1, wherein the first magnetic layer has a saturation magnetic flux density of 1.8 (T) or more.   3. The magnetic pole film for perpendicular magnetic recording according to claim 1, wherein a difference between the total magnetic film thicknesses of the first magnetic layer and the second magnetic layer is zero.   4. The magnetic pole film for perpendicular magnetic recording according to claim 1, wherein the content of Fe in the second magnetic layer is 20 (at.%) Or less.   The magnetic pole film for perpendicular magnetic recording according to any one of claims 1 to 4, wherein the thickness of the second magnetic layer is 1 nm or more and 5 nm or less.   5. The magnetic pole film for perpendicular magnetic recording according to claim 1, wherein the thickness of each first magnetic layer is 10 nm or more and 70 nm or less.   7. The magnetic pole film for perpendicular magnetic recording according to claim 1, wherein any one of Ru, Rh, Cr, Cu, Re, Au, Ag, Pt, and Pd is used for the nonmagnetic layer.   8. The magnetic pole film for perpendicular magnetic recording according to claim 1, wherein the second magnetic layer is made of a metal material other than a body-centered cubic structure.   9. A thin-film magnetic head including a perpendicular magnetic recording element using the perpendicular magnetic recording magnetic pole film according to claim 1.   The thin film magnetic head according to claim 9, comprising an MR element as a reproducing element. A magnetic pole film in which a magnetic layer and a nonmagnetic layer are alternately stacked, and the magnetic layer is antiferromagnetically coupled through the nonmagnetic layer, wherein the magnetic layer includes a first magnetic layer and a second magnetic layer. A thin film magnetic head comprising a magnetic pole film for perpendicular magnetic recording, wherein the second magnetic layer is disposed between the nonmagnetic layer and the first magnetic layer,
A slider arranged to face the recording medium;
A head gimbal assembly having a suspension for elastically supporting the slider. A head gimbal assembly according to claim 11;
A head arm assembly having an arm to which the head gimbal assembly is attached. A carriage with a plurality of arms;
12. A head stack assembly having a head gimbal assembly according to claim 11 attached to each arm of the carriage. A magnetic pole film in which a magnetic layer and a nonmagnetic layer are alternately stacked, and the magnetic layer is antiferromagnetically coupled through the nonmagnetic layer, wherein the magnetic layer includes a first magnetic layer and a second magnetic layer. The second magnetic layer includes a thin film magnetic head including a perpendicular magnetic recording magnetic pole film disposed between the nonmagnetic layer and the first magnetic layer, and is driven to rotate. A slider arranged to face the disk-shaped recording medium;
And a positioning device that supports the slider and positions the slider relative to the recording medium.

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