JPH11259841A - Head assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the noise from being generated in a reproduced output by providing a magnetic shield for absorbing the magnetic field leaked from an electromagnetic drive part between a slider and an actuator, and providing a suspension to the actuator. SOLUTION: This head assembly is constituted by joining a slider 1, a magnetic shield 4, an actuator 2 and a suspension 3. At the time of joining them, adhesives are respectively locally coated between the slider 1 and the magnetic shield 4, between the magnetic shield 4 and the actutator 2 and between a movable part 22 and the suspension 3. Thus, the side of the anti-floating surface of the slider or the side of the anti-electromagnetic drive part is imparted with the same magnetic shield effect as that obtained by adding a magnetic shield material by sputtering or plating by incorporating soft magnetic particles into a conductive adhesive or an insulative adhesive adhering the slider and the actuator thereby imparting the magnetic shield effect to the adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head assembly used in fields such as magnetic recording.

[0002]

2. Description of the Related Art In recent years, in the field of hard disk drives (hereinafter referred to as HDDs), which are magnetic recording devices, the recording density has been rapidly improved, and magnetic heads and recording media have been developed to cope with higher recording densities. It is getting. 2. Description of the Related Art A magnetoresistive head (hereinafter, referred to as an MR head) compatible with a high recording density is manufactured with a track width of about 1 μm.

[0003] The recording density is increasing at a speed approaching 5 GB / in2. In such a situation, MR
A method of driving a suspension holding the slider by a voice coil motor has been used for an operation of reproducing a magnetic signal by moving a slider provided with a head to a track on a recording medium, that is, tracking.

First, a conventional head assembly will be described. The head assembly is an assembly in which a slider is provided with an MR head and a suspension is provided. In the HDD, the position of a slider is controlled by a voice coil motor (hereinafter, referred to as VCM) connected to the head assembly, so that the magnetic head of the head assembly is placed on a track of a recording medium (hereinafter, referred to as a disk). Position.

[0005] Tracks having a width of several μm or less are defined on the disk, and the tracks are also close to each other. On the other hand, the slider has an air bearing surface and an MR head. The air bearing surface is a portion facing the disk, which receives a flow of air generated by the rotation of the disk and generates a force for floating the slider from the disk. The MR head has a function of magnetically recording information on a disk and reproducing magnetically recorded information.

When the track width of the recording medium further narrows with the improvement of the recording density, the head assembly is moved to a VC.
In the method of driving only with M, it is difficult to secure sufficient tracking accuracy. Therefore, it is conceivable that the noise level rises due to the influence of the signal of the adjacent track, and a problem that recording and reproduction cannot be performed correctly occurs.

Further, if the driving speed of the head assembly by the VCM is low with the increase of the recording / reproducing frequency, even if the signal frequency of the electronic circuit for processing the recording / reproducing signal is increased, the recording / reproducing of the entire HDD is performed. The improvement of the reproducing operation speed cannot be obtained. It is becoming difficult to perform a tracking operation for moving the MR head to a minute track area with only a VCM provided at the base of the suspension in a structure in which a gimbal or a suspension is provided on a slider on which the MR head is mounted.

A description will be given of a conventional invention which attempts to solve such difficulties. As an example using an electromagnetic drive type actuator, 0272-1708 / 94
IEEE 52-57 "SILICON MICR
OSTRUCTURES AND MICROACTU
AFOR FOR COMPACT COMPUTER
ISK DRIVE ”, an example using an electrostatic drive type actuator is IEEE Catalog Num.
BER 97CH36021 pp. 378-382 “IN
VER MEMS MILLIACTUATOR FO
R HARDDISK DRIVE APPLICAT
ION ”pp. 454-459“ ANGULAR MIC
ROPOSITIONER FOR DISK DRI
VES ”includes a slider 901 having an air bearing surface 911.
, Actuator 902, suspension 903
Is disclosed. FIG.
FIG. 1 is a three-dimensional view schematically illustrating this conventional head assembly.

Although not shown in FIG. 11, the actuator 902 has a movable part on the substrate, and performs tracking by rotating or linearly moving the slider by rotating or linearly moving the movable part. . This structure attempts to compensate for the limitation of the suspension driving accuracy by the voice coil motor with the actuator provided on the slider.

FIG. 12 is a cross-sectional view taken along the line CC 'of the head assembly of FIG. Actuator drive unit 92
Numeral 1 is fixed to the slider 901, and the movable portion 922 is fixed to the suspension 903 side. Movable part 92
By rotating or linearly moving the slider 2, the slider 901 is rotated or linearly moved, and the MR head 12 is accurately tracked to a predetermined position.

[0011]

As a driving system of an actuator mounted on such a head assembly, an electrostatic system and an electromagnetic system can be considered. Next, by comparing the features of the two, a problem to be solved when realizing a method suitable for the head assembly technology will be described.

The electrostatic force method is a method of controlling the electric attraction between the electrode having a positive charge and the electrode having a negative charge by the amount of charge. The advantage of this method is that no electromagnetic noise is generated from the control of the charge amount. on the other hand,
The disadvantage is that the driving voltage for holding the charge amount needs a high value of about several tens of volts, so that dielectric breakdown may occur in the adjacent MR head. Also, it is difficult to remove electrical noise generated by switching high voltage. Furthermore, since computer systems such as personal computers are driven by a power supply of several volts,
It is necessary to add a step-up power supply to D or a personal computer.

The electromagnetic system is a means for generating a magnetic field (hereinafter referred to as a means for generating a magnetic field)
This is a method of controlling the magnetic attractive force acting between the magnetic material and the magnetic material by the strength of the magnetic field. The advantage of this method is that the voltage for driving the magnetic field generating means may be a low value of about several volts, and does not require a step-up power supply. on the other hand,
The disadvantage is that the magnetic field leaks from the magnetic field generating means, that is, electromagnetic noise is generated.

Considering that the HDD main body is also downsized / thinned, and the personal computer equipped with the HDD is also downsized, thinned and lightened, and there is no room for mounting a step-up power supply. It is desirable to use an electromagnetic system for the head assembly.

However, in the MR head, the amplitude of the reproduction output, which is an electric signal, is about 0.2 (mV), and when an external electromagnetic noise is received, the noise is superimposed on the reproduction signal. The S / N ratio (reproduction output / noise) of the MR head may be easily deteriorated by the magnetic field leaked from the actuator using the electromagnetic method. Unless the problem of noise generated by the magnetic field leaked from the actuator is solved, it is difficult to adopt the electromagnetic method.

Accordingly, the present invention solves this problem and provides M
Without deteriorating the S / N ratio of the reproduction output of the R head,
It is another object of the present invention to provide a head assembly capable of performing accurate tracking.

[0017]

According to the present invention described below, a magnetic field leaking from a magnetic field generating means constituting an actuator is effectively absorbed by a magnetic shield provided in the vicinity of the actuator, and a slider provided with the actuator is provided. , The occurrence of noise in the reproduction output of the MR head can be suppressed.

A head assembly according to the present invention includes a slider having an MR head and an actuator having an electromagnetic drive unit, and a magnetic shield between the slider and the actuator for absorbing a magnetic field leaked from the electromagnetic drive unit. And a suspension joined to the actuator.

Further, the head assembly of the present invention comprises:
The slider, the magnetic shield, the actuator, and the suspension are each assembled using a conductive adhesive or an insulating adhesive.

Further, in the present invention, a slider having a magnetic shield material previously added by sputtering or plating, and an actuator and a suspension are assembled on the anti-floating surface side of the slider using a conductive adhesive or an insulating adhesive, respectively. It is a head assembly characterized by the above.

Further, the head assembly of the present invention comprises an actuator having a magnetic shield material previously added by sputtering or plating on the anti-electromagnetic drive side of the actuator, and a conductive adhesive or insulating material in the order of slider, actuator and suspension. It is characterized by being assembled using an adhesive.

Further, the head assembly of the present invention comprises:
The magnetic shield, the actuator, and the suspension are assembled using a conductive adhesive or an insulating adhesive at a step portion provided on the surface on the side opposite to the floating surface of the slider. This is a head assembly in which the thickness of the assembly is substantially reduced.

According to the present invention, the magnetic shield reduces the leakage magnetic field generated from the electromagnetic drive unit of the actuator by two.
(G) It is preferred to be less than or equal to.

In the present invention, the magnetic shield is a soft magnetic film having a thickness of 1 μm or more. In the present invention, the magnetic shield is an amorphous or crystalline magnetic film.
In the present invention, the magnetic shield is 5000
(G) A head assembly characterized by having the above saturation magnetic flux density BS.

Further, the present invention is characterized in that the conductive adhesive or the insulating adhesive for bonding the slider and the actuator contains soft magnetic particles and has a magnetic shielding effect.

The present invention also provides a conductive adhesive or an insulating adhesive for bonding a slider and an actuator,
Soft magnetic particles are included to provide a magnetic shielding effect, and the same magnetic shielding effect as when a magnetic shielding material is added by sputtering or plating on the slider's anti-floating surface side or actuator's anti-electromagnetic drive side is provided. It is a head assembly characterized by the above.

Further, in the head assembly according to the present invention, a total thickness of the slider, the magnetic shield and the actuator is in a range of 0.3 to 0.65 mm. In addition, an HDD using this head assembly can achieve a thinner disk and a higher capacity by narrowing a disk interval.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below with reference to the drawings. First, the present invention will be described with reference to FIGS.

[Embodiment 1] FIG. 1 is an assembly view showing an embodiment of a head assembly according to the present invention. The head assembly in FIG. 1 is configured by joining a slider 1, a magnetic shield 4, an actuator 2, and a suspension 3. Further, details of each component will be described. The slider 1 has an air bearing surface 11 and an MR head 12 surrounded by a protection member 14.
And a pad 15 which is an electrode of the MR head. The actuator 2 has, on a substrate 20, an electromagnetic driving unit 21, a movable unit 22 rotated by the electromagnetic driving unit, and a terminal 23 for supplying a current to the electromagnetic driving unit. Suspension 3
Has a terminal 31, which is an electrode, and a printed wiring 32 connected to the terminal. Slider 1 and magnetic shield 4
The total thickness of the actuator 2 and the actuator 2 was 0.62 mm, and the thickness of the actuator 2 was 0.15 mm.

In FIG. 1, the components are shown separately for easy understanding of the structure. However, as an actual head assembly, four components are joined and used. When joining,
An adhesive is locally applied between the slider 1 and the magnetic shield 4, between the magnetic shield 4 and the actuator 2, and between the movable part 22 and the suspension 3. FIG. 2 is a cross-sectional view of the head assembly of the present invention thus joined. FIG. 2 shows a cross section along AA 'shown by a chain line in FIG. Although the description of the adhesive is omitted, a part of the wire 33 is described to show a state in which the terminal and the pad are electrically connected by a wire.

[Embodiment 2] FIG. 3 is a sectional view showing an assembly of a slider and an actuator according to the present invention. FIG. 3 shows that the magnetic shield 4 is bonded via an adhesive to the MR head 12 surrounded by the protective member 14 and the slider 1 having the floating surface 11 via an adhesive, and further to the magnetic shield 4 via an adhesive. The actuator 2 is joined to the actuator. Here, examples of the magnetic shield 4 include a soft magnetic metal foil, an organic film containing magnetic particles, a film having conductivity and soft magnetism, or a combination of at least two of these. Slider 1 and magnetic shield 4
The total thickness of the actuator 2 and the actuator 2 was 0.62 mm, and the thickness of the actuator 2 was 0.15 mm. Further, the adhesive preferably has at least one property among properties such as conductivity, thermosetting property, and ultraviolet curing property. Although the magnetic shield 4 has substantially the same size as the actuator 2 in FIG. 3, the magnetic shield 4 may have substantially the same size as the slider 1 as shown in FIG.

The procedure of the manufacturing process of the head assembly will be described with reference to FIG. The slider is fixed on the jig with the floating surface facing down, an adhesive is applied to the counter-floating surface side of the slider 1, and a 10 μm thick NiFe alloy (Ni 45 wt%, Fe 55 wt%) thin film is attached.
Cured in air at 120 ° C. for 1 hour. Thereafter, an adhesive was similarly applied to the NiFe alloy thin film as a magnetic shield, the actuator 2 was fixed at a predetermined position, and cured in air at 120 ° C. for 1 hour. Although the resin bonding step was performed in two steps, it goes without saying that the slider, the magnetic shield, and the actuator can be bonded at one time.

The slider is formed on a circular or square substrate using photolithography and a film forming technique.
After the formation of the protective member 14 and the protective member 14, it can be cut into strips called “rows”, and after the air bearing surface 11 is processed, it can be cut. The thickness direction of the substrate is the length L of the slider. Paste the magnetic shield with adhesive in the low state,
The magnetic shield may be cut into a slider, but the magnetic shield was peeled off or turned up by washing after the cutting, so that the magnetic shield was bonded with the slider.

[Embodiment 3] FIG. 4 is a sectional view showing an assembly of a slider and an actuator according to the present invention. FIG. 4 shows an actuator 2 joined to a slider 1 having an MR head 12, a flying surface 11, and a magnetic shield 4 surrounded by a protective member 14. The total thickness of the slider 1 and the actuator 2 was 6.2 mm, and the thickness of the actuator 2 was 0.15 mm. Since the slider 1 has the magnetic shield 4 on almost the entire surface on the side opposite to the floating surface, it can effectively absorb electromagnetic noise generated from the actuator 2. However, it is preferable that the pad 15, which is an electrode of the MR head 12, and the magnetic shield 4 are insulated from each other without being in contact with each other. The magnetic shield 3
Is provided on the anti-floating surface side of the slider 1 and the protection member 14
May not be in contact. The description of the suspension is omitted in FIGS. 3 to 5 and 8.

The magnetic shield on the side opposite to the flying surface of the slider 1 was formed by adding a NiFe alloy (Ni 45 wt%, Fe 55 wt%) with a thickness of 6 μm by sputtering at the above-mentioned low stage. When sputtering is used, a magnetic shield can be formed directly on the side opposite to the flying surface of the slider, so that it is not necessary to use a resin. It is also possible to add a magnetic shield by using sputtering in the state of the slider without performing the processing in the state of the low state. Plating can achieve a film forming speed about 10 times faster than sputtering, but in the case of a low or slider, there are problems such as difficulty in removing electrodes and protection of the MR head from the plating solution. If you adopt the method of
Easy to manufacture. As described above, since the magnetic shield is added to the slider in advance, it is only necessary to bond the slider and the actuator with an adhesive, so that the process can be shortened and the handling becomes easy.

Embodiment 4 FIG. 5 is a sectional view showing an assembly of a slider and an actuator according to the present invention. FIG. 5 shows that the actuator 2 is bonded to the MR head 12 surrounded by the protection member 14 and the slider 1 having the floating surface 11 on the side opposite to the floating surface via an adhesive. Here, the description of the adhesive and the terminals of the actuator will be omitted. Actuator 2
The magnetic shield 4 is provided on the lower surface of the substrate 20, and the electromagnetic drive unit 21 and the movable unit 22 are provided on the upper surface of the substrate 20. The thickness of the region where the slider 1 and the actuator 2 were joined was about 0.62 mm.

The addition of a magnetic shield to the lower surface of the substrate of the actuator was performed by using sputtering, vapor deposition, and plating. In this case, it was more advantageous to use plating than sputtering and vapor deposition. First, plating is about 10 times faster in film formation. The other is that the thickness direction of the actuator matches the thickness direction of the actuator substrate,
This means that a magnetic shield can be added before machining into a row or a single piece. The magnetic shield may be plated on the actuator substrate before or after the electromagnetic drive unit 21 and the movable unit 22 are provided. However, in consideration of handling and the like, it is better to add the magnetic shield at an early process stage. Magnetic shield 4, electromagnetic drive unit 21 and movable unit 2
The actuator substrate provided with 2 was cut by machining to obtain an actuator 2. Since the magnetic shield is added to the actuator in advance, it is only necessary to bond the slider and the actuator with an adhesive, so that the process can be shortened and the handling becomes easy.

[Embodiment 5] FIG. 6 is a sectional view of a head assembly according to the present invention. FIG. 6 shows a step 131 on the side opposite to the floating surface of the slider 1 having the MR head 12 and the floating surface 11.
This is a head assembly in which the actuator 2 is provided on the flat surface 134 due to the step, and the suspension 2 is further provided on the actuator 2. The actuator 2 has a structure in which the magnetic shield 4 is joined to the lower surface of the substrate 20, the electromagnetic drive unit 21 is embedded in the upper surface, and the movable unit 22 is provided in the electromagnetic drive unit 21. The thickness of the slider was 0.47 mm, and the slider thickness of the portion provided with the step portion was 0.25 mm. The thickness of the actuator including the thickness of the magnetic shield is 0.16 mm, and the total thickness of the slider, the magnetic shield and the actuator can be reduced to 0.41 mm. As shown in this figure,
By joining the actuator to a region where the thickness of the slider is reduced, it is possible to reduce the thickness of the entire head assembly even if the thickness of the magnetic shield is increased. In addition, the allowable value of electromagnetic noise that can be absorbed by the magnetic shield can be increased. Although a magnetic shield has been added to the actuator in advance, a magnetic shield may be added to the slider in advance, or the magnetic shield may be manufactured and assembled independently.

[Embodiment 6] FIG. 7 is a sectional view of a head assembly according to the present invention. FIG. 7 shows a head assembly in which a groove 130 is formed on the side opposite to the floating surface of the slider 1 having the MR head 12 and the floating surface 11, the actuator 2 is provided in the groove 130, and the suspension 3 is further provided on the actuator 2. . The actuator 2 includes a substrate 20
The magnetic shield 4 is joined to the lower surface of the device, the electromagnetic drive unit 21 is embedded in the upper surface, and the movable unit 2 is attached to the electromagnetic drive unit 21.
2 is provided. In this drawing, not only the same effect as in the structure of FIG. 6 can be obtained, but also the strength of the slider can be secured by forming the joint region of the actuator as a groove. That is, the structure in which the groove is not formed serves as a beam.

[Embodiment 7] FIG. 8 is a sectional view showing an assembly of a slider and an actuator according to the present invention. FIG. 8 shows that the magnetic shield 4 is joined to the MR head 12 surrounded by the protective member 14 and the slider 1 having the floating surface 11 on the side opposite to the floating surface.
Further, the actuator 2 is joined to the magnetic shield 4. Here, examples of the magnetic shield 4 include an adhesive containing magnetic particles, an adhesive containing a conductive and soft magnetic substance, or a combination of at least two of them. The total thickness of the slider 1, the magnetic shield 4, and the actuator 2 is 0.62 mm,
The thickness of the actuator 2 was 0.15 mm. Since the adhesive has a magnetic shielding effect, there is no need to separately prepare a magnetic shield, so that the process can be simplified.

20 vol% of carbon steel powder having a diameter of about 5 μm was mixed with the adhesive, and about 1 vol.
The coating was applied to a thickness of 5 μm, the actuator was placed at a predetermined position, and the hardening bonding was performed in a nitrogen atmosphere at 120 ° C. for 1 hour. Soft magnetic material mixed with resin is Sendust or NiFe
Or an oxide such as MnZn ferrite.

[Embodiment 8] FIG. 9 shows a three-dimensional view of a head assembly according to the present invention. FIG. 9 shows a member in which a magnetic shield 4 is joined to the MR head 12 surrounded by the protective member 14 and the slider 1 having the floating surface 11 on the side opposite to the floating surface, and the actuator and suspension are integrated with the magnetic shield 4. To 25. Further, FIG. 10 shows a cross section taken along dashed line BB ′ in FIG. FIG. 10 is a sectional view of a head assembly according to the present invention, which is characterized by a structure in which a suspension and an actuator substrate are integrated. By incorporating the electromagnetic drive unit and the movable unit in the suspension, it is possible to reduce the number of parts, shorten the head assembly process, and reduce the thickness. The magnetic shield preferably has a structure in which the slider is previously added to the slider by sputtering or vapor deposition.
An adhesive such as that shown in FIG. 8 may also serve as a magnetic shield, but if resin adheres and hardens to a portion other than the movable portion 22 of the actuator, the movement of the actuator movable portion is impeded and no function is achieved. In addition, the flying characteristics when the slider flies above the disk cannot be obtained. It would not be a problem if the adhesion of the resin to parts other than the movable part could be completely prevented, but it is difficult in terms of work, so it is desirable to add a magnetic shield material to the slider on the side opposite to the floating surface in advance.

In the head assembly of the present invention, the slider provided with the actuator may be of any type, such as a floating type, a semi-contact type, and a contact type. Here, the floating type is also called a non-contact type. The semi-contact type is also called a near-contact type, and the slider is in a contact state or a non-contact state with the disk during tracking or signal reproduction. In the contact type, a part of the slider contacts the disk. Among these, it is particularly desirable to use it as a floating slider.

The floating type has a smaller frictional load on the actuator when tracking the slider than the contact type. Therefore, since the floating type can rotate or linearly move the slider with a smaller force than the contact type, the power or voltage supplied to the electromagnetic drive unit of the actuator can be kept low. Also, the thickness of the actuator can be reduced. Slider moves between tracks at high speed (hereinafter referred to as seek)
At this time, if the center of gravity of the slider becomes high, the sink of the slider becomes large, and it becomes difficult to keep the flying height, which is the distance between the MR head and the disk, constant. For this reason, it is important to reduce the thickness of each of the slider, the magnetic shield, and the actuator and to reduce the weight. In addition, by reducing the thickness of the head assembly, it is possible to reduce the distance between the disks, thereby realizing a higher capacity HDD. For these reasons, the total thickness of the slider 1, the magnetic shield 4, and the actuator 2 is equal to 0.
It is desirable to be in the range of 3 to 0.65 mm.

[0045]

As described above, by inserting a magnetic shield made of a soft magnetic material between the slider and the actuator, the leakage magnetic field from the actuator is absorbed, and the magnetic head provided in the slider is provided with a magnetic shield. It is possible to effectively suppress the deterioration of the / N ratio.

[Brief description of the drawings]

FIG. 1 is an assembly view of a head assembly according to the present invention.

FIG. 2 is a cross-sectional view of a head assembly according to the present invention.

FIG. 3 is an assembly view of a slider and an actuator according to the present invention.

FIG. 4 is an assembly view of the slider and the actuator according to the present invention.

FIG. 5 is an assembly view of a slider and an actuator according to the present invention.

FIG. 6 is a sectional view of a head assembly according to the present invention.

FIG. 7 is a cross-sectional view of a head assembly according to the present invention.

FIG. 8 is an assembly view of the slider and the actuator according to the present invention.

FIG. 9 is a three-dimensional view of the head assembly of the present invention.

FIG. 10 is a cross-sectional view of a head assembly according to the present invention.

FIG. 11 is a three-dimensional view of a conventional head assembly.

FIG. 12 is a cross-sectional view of a conventional head assembly.

[Explanation of symbols]

1 slider, 2 actuators, 3 suspensions, 4 magnetic shields, 11 air bearing surface, 12 MR
Head, 14 protection member, 15 pads, 20 substrates, 2
1 electromagnetic drive part, 22 movable part, 23 terminal, 25 member in which actuator and suspension are integrated,
31 terminals, 32 printed wiring, 33 wires, 4
2 adhesive, 130 grooves, 131 steps, 134 flat surface, 901 slider, 902 actuator,
903 suspension, 911 air bearing surface, 921 drive unit, 922 movable unit

Claims (10)

[Claims] 1. A slider having an MR head and an actuator having an electromagnetic drive unit, a magnetic shield for absorbing a magnetic field leaked from the electromagnetic drive unit is provided between the slider and the actuator. Head assembly characterized by having a joined suspension. 2. A head assembly wherein a slider, a magnetic shield, an actuator, and a suspension are assembled using a conductive adhesive or an insulating adhesive, respectively. 3. A slider in which a magnetic shield material is added by sputtering or plating on the side opposite to the floating surface of the slider, and an actuator and a suspension are assembled using a conductive adhesive or an insulating adhesive, respectively. Head assembly. 4. An actuator on the side opposite to the electromagnetic drive unit,
A head assembly wherein an actuator to which a magnetic shield material is added by sputtering or plating is assembled using a conductive adhesive or an insulating adhesive in the order of a slider, an actuator, and a suspension. 5. A head assembly in which a magnetic shield, an actuator, and a suspension are assembled using a conductive adhesive or an insulating adhesive, respectively, on a step provided on a surface on the side opposite to the floating surface of the slider. 6. The magnetic shield effect according to claim 2, wherein the conductive adhesive or the insulating adhesive for bonding the slider and the actuator contains soft magnetic particles to provide a magnetic shielding effect. The head assembly described in Crab. 7. The magnetic shield according to claim 1, wherein the magnetic shield is a soft magnetic film having a thickness of 1 μm or more.
The head assembly according to any one of the above. 8. The head assembly according to claim 1, wherein said magnetic shield is an amorphous or crystalline magnetic film. 9. The head assembly according to claim 1, wherein the magnetic shield has a saturation magnetic flux density BS of 5000 (G) or more. 10. The total thickness of the slider, the magnetic shield and the actuator is 0.3 to 0.6.
The head assembly according to any one of claims 1 to 9, wherein the distance is in a range of 5 mm.