JPH103636A - Magnetic head device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact type magnetic head device making possible high recording density and improving reliability. SOLUTION: This device is constituted so as to provide a magnetic recording/ reproducing element 12, a contact type magnetic head slider 11 arranging the magnetic recording/reproducing element 12 on the position opposite to a magnetic recording medium and holding it and a support spring (slider support mechanism) 14 supporting the contact type magnetic head slider 11 by proper pressing force for the magnetic recording medium. In such a case, the contact type magnetic head slider 11 is provided with proper mass, and a total area of a part touching to the magnetic recording medium is set in the range from 0.002(mm<2> ) to 0.1(mm<2> ).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head device, and more particularly, to a magnetic disk device used for a peripheral storage device such as a computer, in which a magnetic head portion is slid on a recording medium (magnetic disk). The present invention relates to a contact recording type magnetic head device that performs recording and reproduction.

[0002]

2. Description of the Related Art In recent years, the recording density of a magnetic disk device has been steadily improving every year. However, in order to increase the recording density, a recording medium holding information and a magnetic head for reading and writing the information are required. It is indispensable to narrow the gap between them (hereinafter, referred to as "spacing").

Conventionally, in a hard magnetic disk drive, a magnetic head slider utilizing the buoyancy of air has been used to reduce the slider mass and the pressing load, thereby realizing low spacing, that is, high recording density.

In recent years, a magnetic disk drive of the contact recording type which does not use a floating magnetic head slider has been developed in order to further reduce the spacing. This contact recording type magnetic disk device is described in, for example,
Hamilton: Journal of the Magnetic Society of Japa
n, Vol. 15, Supplement No.S2 (1991) 483-490, Japanese Patent Application No. 5-508808, and H. Hamolton: Concept in C
ontact Recordign, ASME 1992, TRIB Vol. 3 (1992) 12-23,
And so on.

[0005] The contact recording type magnetic head slider described in these documents is characterized by a small size due to a light load and a light mass, and has a mass of 30 [μg] to 1 [mg] and a pressing load of 10 [mg].
A contact type magnetic head slider of [mgf] to 120 [mgf] is described. In this type of contact recording type magnetic disk drive, recording and reproduction are performed by sliding a magnetic head on an extremely smooth recording medium in order to reduce magnetic spacing.

[0006]

On the other hand, in this type of contact recording type magnetic disk drive, in order to ensure the mechanical reliability of the magnetic disk drive, it is natural that the magnetic disk drive cannot be started or the recording cannot be performed. It is required to reduce the frictional force between the magnetic head and the recording medium, which causes the deterioration of the reproduction characteristics, and to reduce the wear of the magnetic head, which causes the deterioration of the recording / reproduction signal.

In particular, a magnetic disk drive of the contact recording type is
Since the magnetic disk and the magnetic head are slid in contact with each other for a long period of time, reduction of the frictional force of the magnetic head slider against the recording medium and enhancement of wear resistance are indispensable issues.

However, in the above-mentioned contact-type magnetic head device, the contact-type magnetic head easily jumps on the magnetic disk due to friction between the contact-type magnetic head slider and the magnetic disk medium. There is a disadvantage that the recording density cannot be increased because the stability of pacing is impaired. Although smoothing the surface of the recording medium is effective in improving the head wear characteristics, it has the disadvantage of increasing the static friction force between the magnetic head and the magnetic recording medium, and further increasing the jump. For this reason, it has been difficult for the conventional contact-type magnetic head of the related art to simultaneously suppress the frictional force and satisfy the head wear characteristics.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a contact-type magnetic head device which solves the disadvantages of the prior art, and in particular, enables a high recording density and improves reliability. With that purpose.

[0010]

To achieve the above object, according to the first aspect of the present invention, a magnetic recording / reproducing element and a magnetic recording / reproducing element are arranged at a position facing a magnetic recording medium and held. A magnetic head slider having a contact type magnetic head slider and a slider support mechanism for supporting the magnetic head slider with an appropriate pressing force against the magnetic recording medium. The total area of the portion that comes into contact with is set in the range of 0.002 [mm ² ] to 0.1 [mm ² ], and a suitable mass is provided.

Therefore, according to the first aspect of the present invention, the total area of the contact pads is 0.002-0.
To experimentally find that by setting an appropriate pressing load and slider mass in the range of 1 [mm ² ], the static friction force between the magnetic head and the medium can be reduced and the wear rate of the head can be reduced. Was completed.

Next, according to the present invention, the mass of the magnetic head slider is set to 2 mg or more,
The slider supporting mechanism applies a pressing force of 1 [g weight] or less to the magnetic head slider described above.

Therefore, according to the second aspect of the present invention,
In addition to functioning equivalently to the first aspect of the present invention, it is possible to more specifically and clearly find a reduction in the static friction force between the magnetic head and the medium and a reduction in the wear rate of the head.

According to the third aspect of the present invention, the contact-type magnetic head slider includes a contact pad having a flat tip end surface, which is disposed in a balanced manner over at least three places on a surface of a portion that contacts the magnetic recording medium. Has been adopted.

Therefore, in the invention according to claim 3,
In addition to functioning in the same manner as the first aspect of the present invention, a stable posture can be maintained for a long period of time.

According to a fourth aspect of the present invention, the above-mentioned contact pad is formed in a quadrangular shape and is provided at four corners on the surface of the magnetic head slider.

Therefore, according to the invention described in claim 4,
In addition to functioning in the same manner as the above-described invention, it is possible to maintain an even more stable posture for a long period of time.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view of a magnetic head device according to the present invention. This magnetic head device is disclosed with the surface facing the magnetic disk facing upward.

In FIG. 1, a magnetic head slider 1
Numeral 1 is made of Al ₂ O ₃ .TiC and has a surface (contact pad) 13 that comes into contact with the magnetic recording medium. The contact pads 13 are provided at three places. That is, the contact pads 13 are firstly provided at both corners (corner portions) of the front end portion (upstream side) of the contact surface of the magnetic head slider 11 with the magnetic disk, and the other contact pad 13 is in contact with the magnetic disk. Equipped at the center of the rear end (downstream side) of the contact surface. Each contact pad 13 has a flat surface (tip surface) at a portion that comes into contact with the magnetic recording medium.

This contact pad 13 is formed by an etching method. The mass of the magnetic head slider and the total area of the contact pads 13 are set relatively small as described later. The above-described magnetic head slider 11 is attached to a support spring 14 as a slider support mechanism, and is always in contact with a magnetic recording medium by an appropriate pressing load as a contact type magnetic head slider.

Further, in this embodiment, a magnetic disk medium 20 shown in FIG. 2 is used as a magnetic recording medium. Here, the magnetic disk medium 20 is electroless-plated with NiP as a hard magnetic disk substrate 21 by 10 [μm], and the surface thereof is mirror-polished to a surface roughness (Rtm) of 2 [nm]. CoP as a magnetic thin film 22 on a 0.5 inch aluminum alloy substrate
A 20 nm thick film of tCr is formed by a sputtering method, and a protective film 23 is formed thereon.

This protective film is made of hydrogen 10 by sputtering.
[%] Is formed by depositing 5 [nm] of added carbon. Further, a perfluoropolyether as the lubricant 24 is further coated thereon by 2 [nm] by an immersion method.

The hard magnetic disk substrate 21 has an outer diameter of 1.8 [inch] and a glide height of 1.0 [μ].
Inch] glass substrate.

Next, the function and usefulness of the above embodiment will be described with reference to a plurality of specific experimental examples.

First, the magnetic head slider and the hard magnetic disk of the embodiment shown in FIGS. 1 and 2 are assembled in a magnetic disk device, and the hard magnetic disk is
The contact pad 13 was continuously contacted at 400 rotations, and the total wear depth of the contact pad 13 after 1000 hours and the static friction force between the contact magnetic head and the magnetic recording medium were examined. Here, the static friction coefficient was measured by a strain gauge method, and the wear depth was measured by an atomic force microscope.

The measured data in this case is shown in FIGS. Among them, FIG. 3 shows measurement data for grasping the state in which the static friction force and the wear rate were improved, and the experiment was conducted with the head slider mass being 6 [mg] and the pressing load being 570 [mgf]. FIG. 7 shows a diagram of the data corresponding to FIG.

As a result, the static friction force sharply decreases as the pad area decreases. In particular, the static friction force decreases to 5.0 gf or less for a pad area of 0.1 mm ² or less.
It has been found that the static friction force is almost constant for a pad area smaller than that. With this level of static friction,
Even if the magnetic head slider and the magnetic disk are left in contact with each other after the apparatus has been operating for a long period of time, there is no possibility that the support spring will be damaged or the magnetic disk device will not start properly.

Further, the wear rate rapidly decreases with an increase in the pad area. For an area of 0.002 [mm ² ] or more, the wear rate is "1.0E-1 [nm / h] or less". Thus, it was found that sufficient recording and reproduction of the magnetic head could be ensured even when the magnetic disk device was operated for about five years.

As described above, when the pad area is between 0.002 and 0.1 mm ² , the static friction force and the wear rate of the magnetic head are at a level that does not cause any problem in the reliability of the magnetic disk drive. It has been found that there is a pad area where the wear rate of the magnetic head can be reduced at the same time.

Next, assuming that the mass of the head slider was 2 [mg], the pressing load and the pad area were changed, and the static friction force and the wear rate were measured (diagram) as shown in FIG.
Shown in FIG. 8 is a diagram of the measurement data of the tables according to FIGS. 4 and 5.

As shown in FIG. 8, the tendency of the change in the static friction force and the wear rate with respect to the pad area was almost the same as the result shown in FIG. 7, but all increased when the pressing load was increased. It turns out that there is a tendency.
When the pressing load exceeds 1 [gf], the wear rate increases rapidly, and the wear rate is 1.0
[Nm / h] or more.

As described above, the pressing load is 1.0 [gf].
Is exceeded, there is no pad area where both the static friction force and the wear rate are small, and the pad area is 0.002 to 0.1 [mm ² ] for a pressing load of 1 [gf] or less.
It has been found that the reliability of the magnetic disk drive can be ensured in the range of.

FIG. 9 shows that the pressing load is 140 [m
gf] shows the results of measuring the static friction force and the wear rate while changing the head slider mass and the pad area. FIG. 9 is a graph of the measurement data of the tables according to FIGS. 5 to 6 described above. As is apparent from FIG. 9, the static friction force was 2.0 or less when the pad area was 0.1 [mm ² ] or less for any slider mass. It was also found that the wear rate hardly changed even when the mass of the head was increased, and was 0.1 [nm / h].

As described above, if the pad area is set to 0.1 [mm ² ] or less with respect to the change in the slider mass,
It became clear that the static friction force and the wear rate were simultaneously suppressed.

On the other hand, by using the magnetic head slider and the magnetic recording medium described in the first embodiment, the fluctuation of the reproduction signal from the recording / reproducing element due to the track deviation at the track density of 1000 [TPI] (the minimum and maximum waveform amplitudes). As a result of examining the ratio of the amplitude, it was found that in a region where the slider mass was 2 [mg] or less and the pressing load was 1 [gf] or less, the fluctuation value increased, and contact recording / reproduction could not be performed. It is considered that this is because the head jump increased due to the low load and light mass, and it was not possible to obtain a stable contact sliding state of the magnetic head recording medium.

From the results shown above, when the total area of the contact pads is in the range of 0.002 to 0.1 [mm ² ],
Pushing load 1 [gf] or less, slider mass 2 [mg]
It has been clarified that the contact-type magnetic head slider can reduce the static friction force between the magnetic head and the medium and at the same time reduce the wear rate of the head.

A contact start and stop (CSS) test, which is one of the mechanical durability tests of the magnetic disk drive, was performed using the combination shown in FIG. It was also confirmed that the mechanical durability of the disk device was maintained and the recording / reproducing characteristics could be performed without any trouble.

Here, another example of the magnetic head slider will be described with reference to FIG.

The magnetic head slider portion shown in FIG. 10 is different from the magnetic head slider portion in that the contact pads 33 are formed in a quadrangular shape and are provided at four corners on the surface of the magnetic head slider 31, and two magnetic heads ( Recording / reproducing element) 32,
32 is provided on the two contact pads 33, 33 on one side. These contact pads 3
3 is formed by an etching method. Other configurations are the same as those of the magnetic head shown in FIG.

In this manner, a magnetic head device having substantially the same functions as those in the case of FIG. 1 can be obtained.

Another example of the magnetic head slider will be described with reference to FIG.

In the magnetic head slider portion shown in FIG. 11, the contact pad 43 is set in a disk shape, and the contact type magnetic head slider 4 is formed similarly to the case of FIG.
It is characterized in that it is provided at a position corresponding to each vertex of an isosceles triangle on the surface of No. 1. In this case, the area of the upper surface of the contact pad 43 provided with the magnetic head (recording / reproducing element) 42 is larger than the area of the upper surface of the other two contact pads 43 as in the case of FIG. Is also set large. These contact pads 43 are formed by an etching method. Other configurations are the same as those of the magnetic head shown in FIG.

In this manner, a magnetic head device having substantially the same functions as those in the case of FIG. 1 can be obtained.

As described above, regarding the results of the above experiments,
Regardless of the number, shape and arrangement of the contact pads, the same effect can be obtained as long as the total area is within the range defined by the present embodiment.

In the above embodiment, an example was shown in which Al ₂ O ₃ .TiC was used as the magnetic head slider material. However, the present invention is not limited to this. , Diamond-like carbon, amorphous carbon, SiC, Al ₂ O ₃ , BN, etc., and the protective film for the magnetic head slider protective film is made of diamond-like carbon, Si, BN, etc. The effect is obtained.

Further, in addition to the above-described embodiment, as a pad forming method, a known forming method such as mechanical cutting can be used without any particular limitation. The method of forming the magnetic thin film 22, the protective film 23, the lubricant 24, the support spring 14, and the like used for the magnetic disk is not particularly limited, and a known material and a forming method may be used without any particular limitation. Can be.

[0048]

As described above, according to the present invention, the area of the magnetic head slider in contact with the recording medium, the mass of the magnetic head slider, and the pressing load are reduced by the frictional force between the magnetic head and the recording medium and the long term. Since the wear of the magnetic head due to the contact sliding is set at the same time, the start and stop of the magnetic disk device due to the increase in the frictional force due to the smoothing of the recording medium can be prevented, and the recording due to the head wear for a long time can be prevented. Since a decrease in reproduction characteristics can be suppressed, it is possible to provide an unprecedented excellent magnetic head device capable of obtaining a contact recording type magnetic disk device with high recording density and high reliability.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a configuration of a hard magnetic disk with which a slider portion of the magnetic head device disclosed in FIG. 1 contacts.

FIG. 3 shows a slider portion (slider mass 6 [mg], pressing load 0.57 [g] of the magnetic head device disclosed in FIG.
6 is a table showing experimental data of the wear rate and the static friction force in the case of [f]).

FIG. 4 is a slider portion (slider mass 2 [mg], pressing load “8.9”) of the magnetic head device disclosed in FIG. 1;
It is a table | surface which shows the wear rate of "3.76""1" [gf]) and the experimental data of a static friction force.

FIG. 5 shows a slider portion of the magnetic head device disclosed in FIG. 1 (in the case of slider mass “2” “15” [mg], pressing load “0.14” “0.089” “0.14” [gf]). 4 is a table showing experimental data of abrasion speed and static friction force in FIG.

FIG. 6 shows the wear rate and the wear rate of the slider portion (in the case of slider mass “6”, “2”, “0.38” [mg], pressing load “0.14” [gf]) of the magnetic head device disclosed in FIG. 4 is a table showing experimental data of static friction force.

FIG. 7 is a graph plotted based on the experimental data of FIG. 3 and showing the contact pad area dependency on pad wear rate and static friction force.

FIG. 8 is a graph showing the dependence of the contact pad area on the pad wear rate and the static friction force with the head pressing load as a parameter, based on the experimental data of FIGS. 4 and 5;

9 is a graph showing the dependence of the contact pad area on the pad wear rate and the static friction force with the slider mass as a parameter, based on the experimental data of FIGS. 5 and 6. FIG.

FIG. 10 is a perspective view showing another example of the slider portion of the embodiment disclosed in FIG. 1;

FIG. 11 is a perspective view showing still another example of the slider portion of the embodiment disclosed in FIG. 1;

[Explanation of symbols]

 11, 31, 41 Magnetic head slider 12, 32, 42 Recording / reproducing element (magnetic head) 13, 33, 43 Contact pad 14 Support spring as slider support mechanism 20 Hard magnetic disk medium (magnetic recording medium)

Claims (4)

[Claims] 1. A magnetic recording / reproducing element, a contact type magnetic head slider which is arranged at a position facing a magnetic recording medium and holds the magnetic recording / reproducing element, A magnetic head device having a slider support mechanism for supporting the recording medium with an appropriate pressing force, wherein the contact-type magnetic head slider has an appropriate mass and has a total area of a portion in contact with the magnetic recording medium. A magnetic head device characterized in that it is set in a range of 0.002 [mm ² ] to 0.1 [mm ² ]. 2. The contact type magnetic head slider has a mass set to 2 mg or more, and the slider support mechanism applies a pressing force of 1 g weight or less to the magnetic head slider. 2. The magnetic head device according to claim 1, wherein the magnetic head device is configured as follows. 3. The contact type magnetic head slider according to claim 1, further comprising a contact pad having a flat tip end surface at least at three positions on a surface of a portion in contact with the magnetic recording medium. The magnetic head device according to the above. 4. The magnetic head device according to claim 3, wherein the contact pads are set in a quadrangular shape and are provided at four corners on a surface of the contact type magnetic head slider.