JP2599380B2 - Levitated magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a flying type thin film magnetic head, in which a floating surface of a slider has a flat shape without a tapered surface, and a ridge portion on an air inflow end side, In addition, by making all the ridges appearing in the width direction perpendicular to the air flow direction to be arc-shaped, even if the flying height is reduced, it is unlikely to crash with the magnetic disk, suitable for high density recording ,And,
It is an object of the present invention to provide a flying-type thin-film magnetic head which can follow at high speed and can start smoothly without causing catching.

<Prior Art> A flying type thin film magnetic head uses a dynamic pressure generated by the viscosity of air when moving relatively to a magnetic disk to generate a small flying height between the magnetic disk surface and the magnetic disk. For example, a Winchester-type thin-film magnetic head, a composite-type thin-film magnetic head, a thin-film thin-film magnetic head, and the like are known. Its basic structure is
As shown in FIG. 8, a read / write element 2 is attached to an end face of a slider 1 made of a ceramic structure.

The slider 1 has flying surfaces 103, 104 on rails 101, 102 projecting from the surface facing the magnetic disk at intervals.
And a tapered surface at the tip of the air bearing surfaces 103 and 104.
A so-called taper provided with 103a and 104a. It is a flat type. The rail portions 101 and 102 are formed at intervals so as to prevent swinging in the left and right directions and to ensure floating stability. The read / write element 2 is a thin film element formed according to a process similar to the IC manufacturing technology in the drawing, and is covered with a protective film 11. The protective film 11 is provided on the side surface on the air outflow end side of the slider 1 so as to constitute a part of the slider 1.
3 and 101.

When used as a magnetic disk drive, the flying thin-film magnetic head is mounted on the tip of a gimbal-based head support device, and the flying surfaces 103 and 104 of the slider 1 are arranged so as to face the surface of the magnetic disk. start. Drive by stop method. FIG. 9 is a diagram schematically showing the configuration of a magnetic disk drive, wherein 3 is a magnetic disk, 5 is a thin-film magnetic head, and 6 is a gimbal head support device. When the magnetic disk 3 is stationary, the flying surfaces 103 and 104 are pressed against the surface of the magnetic disk 3 by the spring pressure of the head support device 6, but when the magnetic disk 3 rotates in the direction of arrow a, the slider Floating surface including one tapered surface 103a, 104a
Lift dynamic pressure is generated in 103 and 104, and the dynamic pressure and the head support device 6
With the floating amount g that balances with the spring pressure P of In the floating state, it is normal to be in a state of rising forward by a predetermined pitch angle θ1.

The dynamic pressure is applied to the air bearing surface 10 of the rail portions 101 and 102 of the slider 1.
The dimensions of 3, 104, the taper angles of the tapered surfaces 103a, 104a, the dimensions, and the relative movement speed between the magnetic disk and the like are determined. The flying height g and the pitch angle θ1 are determined by the dynamic pressure and the spring pressure of the head support device. Is determined. So, conventionally,
The distance between the rail portions 101 and 102 of the slider 1 and the air bearing surfaces 103 and 104
, The taper angles and dimensions of the tapered surfaces 103a and 104a, and the spring pressure of the head support device are appropriately designed to obtain a predetermined flying height g and a pitch angle θ1. The above taper. Flying type thin film magnetic heads using flat type sliders are widely used at present because stable flying characteristics can be obtained in a range of flying height of about 0.25 to 1 μm.

<Problems to be Solved by the Invention> By the way, in this type of flying type thin film magnetic head, in order to reduce spacing loss and achieve high recording density,
The flying height tends to be smaller, for example, 0.2 μm or less. In addition, in combination with a computer, high-speed followability has been required in order to cope with high-speed data transfer and processing.

However, the aforementioned taper. A floating type thin film magnetic head using a flat type slider has tapered surfaces 103a and 104a on one end side when viewed in the air flow direction. Therefore, the total length of the slider 1 is L, and an intermediate portion (L / 2 In the general support state in which the spring load P is applied in (1), it is difficult to increase the pitch angle θ1, and the magnetic head tends to crash with the magnetic disk 3. This problem is particularly likely to occur when the flying height is reduced in order to cope with a high recording density.

In addition, since the mass is different between the air inlet side having the tapered surfaces 103a and 104a and the air outlet end side with the load point as a boundary, the inertia moment on the air inlet side and the inertia on the air outlet side are centered on the load point. The moment and the moment are unbalanced, and the moment of inertia of the thin-film magnetic head as a whole is substantially increased. For this reason, the follow-up property is deteriorated, and it is difficult to satisfy the high-speed follow-up property to cope with the high-speed data transfer and processing.

Therefore, an object of the present invention is to solve the above-described conventional problems, and it is difficult to cause a crash even when the flying height is reduced to, for example, 0.2 μm or less, suitable for high recording density, and capable of high-speed tracking, and An object of the present invention is to provide a flying-type thin-film magnetic head that can start smoothly without catching.

<Means for Solving the Problems> In order to solve the above-described problems, a flying type thin film magnetic head according to the present invention has a read / write element attached to a slider having a floating surface on a surface side facing a magnetic storage medium. . The read / write element is a thin film element, is provided on a side surface of the slider on the air outflow end side, and is covered with a protective film. The protective film is provided on a side surface on the air outflow end side of the slider so as to constitute a part of the slider, and constitutes the floating surface together with the slider. The flying surface of the slider including the protective film is planar over the entire surface, and has a ridge on the air inflow end side, and all ridges appearing in a width direction orthogonal to the air flow direction. Is arc-shaped.

<Operation> Since the flying surface of the slider is flat over the entire surface, when the load point is set at the middle of the slider, the dynamic pressure generated in front of the load point increases. For this reason, the pitch angle becomes large, and even if the flying height is reduced to, for example, 0.2 μm or less in order to improve the recording density, a crash hardly occurs.

Also, if the slider's flying surface is flat without a tapered surface, if the load point is set in the middle of the slider, the mass before and after the load point will be balanced, and the moment of inertia will be reduced at the air inflow and outflow ends. Side substantially equal.
For this reason, the moment of inertia of the entire thin-film magnetic head is reduced, the follow-up property is improved in relation to the magnetic disk, and a thin-film magnetic head with high-speed follow-up is obtained.

Moreover, the air bearing surface has an arc-shaped ridge on the air inflow end side. At the start, air, which is a viscous fluid, smoothly enters between the magnetic disk and the air bearing surface through the arc-shaped portion. For this reason, it is possible to start smoothly without causing a catch.

Furthermore, since all the ridges appearing in the width direction orthogonal to the air flow direction are also arc-shaped, even when the thin-film magnetic head is swung on the magnetic disk in a floating state, it is caught. And the likelihood of crashes in the flying state, damage due to hooking with the magnetic disk, and the like are less likely to occur.

The read / write element is a thin film element, is provided on the side surface on the air outflow end side of the slider, and is covered with a protective film.
The protective film is provided on a side surface on the air outflow end side of the slider so as to form a part of the slider, and forms a floating surface together with the slider. The flying surface of the slider including the protective film is planar over the entire surface, and the ridges on the air inflow end side and all ridges appearing in the width direction perpendicular to the air flow direction are formed. It has an arc shape. Therefore, according to the present invention, even in the portion of the protective film unique to the thin-film magnetic head, it is unlikely to cause a crash, suitable for high recording density, capable of following at high speed, and starting smoothly without causing catching. obtain.

<Embodiment> FIG. 1 is a perspective view of a flying type thin film magnetic head according to the present invention, and FIG. 2 is an enlarged cross-sectional view of a main part of the same. In the figure, the same reference numerals as those in FIG. 8 indicate identical components. The read / write element 2 is a thin film element, is provided on the side surface of the slider 1 on the air outflow end side, and is covered with a protective film 11. The protective film 11 is provided on the side surface on the air outflow end side of the slider 1 so as to constitute a part of the slider 1, and together with the slider 1, constitutes the floating surfaces 103 and 104. The flying surfaces 103 and 104 of the slider 1 including the protective film 11 are entirely flat without a tapered surface. Ends (a) and (b) of the air bearing surfaces 103 and 104 viewed in the direction of air flow
Is formed in an arc shape. The edges (c) and (d) appearing in the width direction orthogonal to the air flow direction are also formed in an arc shape. An appropriate arc shape is an arc having a radius of about several μm.

FIG. 3 is a perspective view showing another embodiment of the flying type thin film magnetic head according to the present invention. In this embodiment, the flying surface 105 of the slider 1 has its entire surface formed in a flat shape having no rail portion, and its edges (a) to (d) formed in an arc shape.

In any of the embodiments, the air bearing surfaces 103 to 105 have an arc-shaped ridge on the air inflow end side.
At the start, air, which is a viscous fluid, smoothly enters between the magnetic disk and the air bearing surface through the arc-shaped portion. For this reason, it is possible to start smoothly without causing a catch. Further, since the ridge corner on the air inflow end side is formed in an arc shape, a crash in a floating state, damage due to being caught by a magnetic disk, and the like hardly occur.

Also, since all the ridges (c) and (d) appearing in the width direction perpendicular to the air flow direction are also arc-shaped, the thin-film magnetic head can be swung on the magnetic disk in a floating state. Even when this is done, no catching occurs, and a crash in the flying state, damage due to catching with the magnetic disk, and the like are less likely to occur.

Furthermore, the entire flying surface 103 to 105 of the slider 1 is
As shown in FIG. 7, when the load point is set at the middle portion of the slider 1, the dynamic pressure generated in front of the load point increases, and the pitch increases, as shown in FIG. The angle θ2 becomes larger than the conventional pitch angle θ1. For this reason, a crash is unlikely to occur. In FIG. 7, a dotted line indicates a conventional floating position.

When the flying surface 105 of the slider 1 has a flat shape without a tapered surface, the mass before and after the load point set at the intermediate portion of the slider 1 is balanced, and the moment of inertia is reduced at the air inflow and outflow end sides. Become substantially equal. Therefore, the moment of inertia of the thin magnetic head as a whole is reduced, the followability is improved, and a thin-film magnetic head capable of high-speed follow is obtained.

The protective film 11 is provided on the side surface of the slider 1 on the air outflow end side so as to form a part of the slider 1, and forms a floating surface together with the slider 1. And protective film
The flying surfaces 103 and 104 of the slider 1 including the surface 11 are flat over the entire surface thereof, and the ridges on the air inflow end side and all ridges appearing in the width direction perpendicular to the air flow direction. Has an arc shape. Therefore, according to the present invention, even in the portion of the protective film 11 unique to the thin-film magnetic head, it is unlikely that a crash occurs, which is suitable for high recording density,
High-speed follow-up is possible, and a smooth start can be made without causing a catch.

 Next, a description will be given based on actually measured data.

FIG. 4 is a diagram showing the conventional floating thin film magnetic head shown in FIG. Emission. FIG. 5 is a view showing flying stability measurement data by a sensor (hereinafter referred to as an AE sensor). FIG. 5 is a view showing flying stability measurement data by an AE sensor of the flying thin film magnetic head according to the present invention shown in FIG. is there. The measurement data shown in FIGS. 4 and 5 are obtained by a measurement system as shown in FIG.

In FIG. 6, 3 is a magnetic disk, 4 is a spindle for driving the magnetic disk 3 to rotate, 5 is a floating type thin film magnetic head, 6 is a head supporting device for supporting the floating type thin film magnetic head 5, 7 is an AE sensor, 8 Is a filter, 9 is an amplifier, 10
Is an oscilloscope. The measurement conditions in FIG. 6 are as follows.

The flying height of the flying thin-film magnetic head 5; 0.18 μm Measurement frequency; 150 kHz to 400 kHz Amplification factor; 60 dB Surface smoothness of the magnetic disk 3; Rmax <100Å Oscilloscope 10; X axis 5 sec / div Y axis 50 mv / div FIG. As shown in the measurement data, the conventional levitation type thin film magnetic head has a large AE sensor output reaching a maximum of 100 mv at a flying height of 0.18 μm. From this,
Taper. It can be seen that in the conventional flying type thin film magnetic head using the flat type slider, when the flying height is as low as 0.18 μm, the flying posture is collapsed and the flying surface collides with the surface of the magnetic disk.

On the other hand, the flying type thin film magnetic head according to the present invention hardly generates an AE sensor output as shown in FIG. From this, it can be seen that the flying thin film magnetic head according to the present invention does not lose its flying attitude and has stable flying characteristics even when the flying height is as low as 0.18 μm.

<Effects of the Invention> As described above, according to the present invention, the following effects can be obtained.

(A) Since the flying surface of the slider is flat on the entire surface, the flying surface of the slider is flat on the entire surface. The angle increases and the flying height is reduced to, for example, 0.
Even when the thickness is reduced to 2 μm or less, it is possible to provide a flying type thin film magnetic head which is compatible with high recording density and hardly causes a crash.

(B) Since the flying surface of the slider is flat over the entire surface, the mass before and after the load point set at the middle portion of the slider can be balanced, and the moment of inertia of the entire thin film magnetic head is small. And a thin-film magnetic head that can follow at high speed.

(C) In the air bearing surface, the ridges on the air inflow end side and all the ridges appearing in the width direction orthogonal to the air flow direction are arc-shaped. At the start,
It is possible to provide a flying thin-film magnetic head that can start smoothly without being caught and hardly causes a crash or a damage due to being caught on a magnetic disk even in a flying state.

(D) Crash is unlikely to occur even in the portion of the protective film unique to the thin film magnetic head, and suitable for high recording density;
High-speed follow-up is possible, and a smooth start can be made without causing a catch.

[Brief description of the drawings]

FIG. 1 is a perspective view of a floating type thin film magnetic head according to the present invention,
FIG. 2 is an enlarged sectional view of a main part of the same, FIG. 3 is a perspective view of another embodiment of the flying type thin film magnetic head according to the present invention,
FIG. 4 shows the conventional floating type thin film magnetic head shown in FIG.
FIG. 5 shows flying stability measurement data by the AE sensor. FIG. 5 shows the flying thin film magnetic head according to the present invention shown in FIG.
FIG. 6 shows a flying stability measurement data by the AE sensor, FIG. 6 shows a measurement system for obtaining the measurement data of FIGS. 4 and 5, and FIG. 7 shows a flying type thin film magnetic head according to the present invention. FIG. 8 schematically shows a configuration of a magnetic disk drive used, FIG. 8 is a perspective view of a conventional floating thin-film magnetic head, and FIG. 9 schematically shows a configuration of a magnetic disk drive using a conventional floating thin-film magnetic head. FIG. 1 ... Slider, 2 ... Read / write element 103, 104, 105 ... Floating surface

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor E ▲ Saki ▼ Ichiro Jyo 1-13-1 Nihombashi, Chuo-ku, Tokyo Inside TDC Corporation (72) Inventor Shinya Oyama 1-1-13 Nihonbashi, Chuo-ku, Tokyo No. 1 Inside TDK Corporation (56) References JP-A-56-101674 (JP, A) JP-A-59-60760 (JP, A) JP-A-53-73129 (JP, A) 11527 (JP, A) Fully open 1987-21069 (JP, U) Fully open 1986-193577 (JP, U) Fully open 1984-149226 (JP, U)

Claims (1)

(57) [Claims] 1. A flying thin-film magnetic head in which a read / write element is attached to a slider having an air bearing surface on a surface facing a magnetic recording medium, wherein the read / write element is a thin film element, and the slider has an air outflow end. Is provided on a side surface of the slider, and is covered with a protection film. The protection film is provided on a side surface on an air outflow end side of the slider,
The slider is provided so as to constitute a part of the slider, and constitutes the flying surface together with the slider. The flying surface of the slider including the protective film has a planar shape over its entire surface, and air A floating thin-film magnetic head, wherein the edge portions on the end side and all the edge portions appearing in a width direction perpendicular to the direction of air flow are arc-shaped.