JPH10312661A - Magnetic head slider and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep contact/start/stop durability and improve a recording and reproducing characteristic by arranging a material with an electric conductivity lower than that of a magnetic head slider in the neighborhood of a magnetic head and forming a protection film on a floating surface, and making the protection film thinner only in the neighborhood of the magnetic head. SOLUTION: Magnetic head sliders 21 are arranged at regular intervals, and a dummy member 25 is arranged around them. After photoresist has been poured and pre-baked, the magnetic head sliders 21 are irradiated with ultraviolet rays from the diagonal direction and also diagonal to the floating surface. Only the photoresist overflowing on the surface of the magnetic head sliders 21 is irradiated with the ultraviolet rays, and the photoresist remains in the intervals after development. In this state, a diamond-carbon film is formed as a protection film. Plasma density is low on the low conductive photoresist and deposition rate becomes low, and it is possible to form the protection film thick in a center part contacting a disk and thin on an air flowing end where magnetic head elements exist.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magnetic head slider used for recording / reproducing information on / from a disk-shaped recording medium, and more particularly, to a method of forming a protective film attached to a floating surface of a magnetic head slider. It is about.

[0002]

2. Description of the Related Art A magnetic disk device for recording / reproducing data on / from a disk-shaped recording medium is widely used as an external storage device of a computer. As shown in FIG. 10, the magnetic disk device is a disk-shaped recording medium 2 on which information is recorded.
7. a magnetic head slider 21 having a magnetic head element (not shown) for recording / reproducing attached thereto, an actuator 29 for moving the magnetic head slider 21 to a predetermined position,
Spindle motor 3 for rotating disk-shaped recording medium 27
1 and a signal processing circuit 33 for processing signals. The magnetic head slider 21 moves the disk-shaped recording medium 27 when the disk-shaped recording medium 27 stops rotating.
However, when rotating, a lift is generated due to the air flow accompanying the rotation of the disk-shaped recording medium 27, and the lift and the head suspension mechanism 35 move the magnetic head slider 21 to the surface of the disk-shaped recording medium 27. A predetermined flying height is obtained by balance with the force of pressing toward.
As described above, when the rotation is stopped, the magnetic head slider is in contact with the surface of the disk-shaped recording medium, and the method of floating during rotation is called a contact start / stop (hereinafter referred to as CSS) method. The magnetic head slider is CS
Every time S, the disk-shaped recording medium is slid and gradually wears out, and the friction coefficient increases with the sliding, so that rotation may not be possible at last. In recent years, especially in a magnetic disk device used for a notebook personal computer, the rotation of a disk-shaped recording medium is stopped when there is no access for a certain time to save power.
Are required to have a CSS durability of 100000 times or more.

In order to realize such high CSS durability, a disk-shaped recording medium is provided with a disk protective film such as carbon on a magnetic recording layer, and is further provided with a lubricant such as perfluoropolyether (PTFE). Coating has been done. Since the lubricant is removed as soon as it is removed by sliding during CSS, fluidity to compensate for it is required, but if the fluidity is too strong, a meniscus is formed between the magnetic head slider and the disk-shaped recording medium to adsorb it. (Stiction) may occur, and rotation may not be started. For this reason,
The magnetic head slider 21 is 10 to 50 with respect to the rotation direction.
It is performed to be processed into a convex shape having a height of nm. This convex shape is called a crown 37. In the magnetic head slider 21 having the crown 31, the air outflow end with the magnetic head element 9 has a minimum flying height and maintains the recording / reproducing characteristics when rotating, as shown in FIG. It comes into contact with the recording medium 27. For this reason, even if a meniscus is generated, the area is limited, so that it is possible to prevent the rotation start from being hindered without a large force. Further, a protective film 39 of 1 to 10 nm is formed on the floating surface for the purpose of reducing the frictional force and improving the wear resistance. The protective film 39 on the magnetic head slider has the effects of reducing the frictional force with the disk-shaped recording medium 27, preventing wear due to sliding, and maintaining the lubricant on the disk-shaped recording medium. As the protective film 39, a diamond-like carbon film is usually used.

Next, a conventional method for manufacturing a magnetic head slider will be described with reference to FIG. First, the magnetic head element 9
Is a sintered substrate 4 mainly composed of alumina and titanium carbide
1 (FIG. 12A). From this, the substrate 41 is cut to obtain a strip-shaped plate having a plurality of magnetic head elements 9 (FIG. 12B). This strip-shaped plate is called row 1. The cut surface of the row 1 is lapped until the height of the magnetic head element 9 becomes a predetermined size.

[0005] Then, on the wrapped surface of row 1,
A 10 nm protective film is formed. The formation of the protective film is performed by a sputtering method, a CVD method, or the like. FIG. 13 shows C
Plasma C used to form protective film by VD method
It is an example of a VD device. After evacuation, a hydrocarbon-based gas such as CH4 or C2H6 is introduced as a material gas 19 into the apparatus. When a predetermined pressure is obtained, a DC voltage is applied to the electrode 17 to which the row 1 is attached to generate plasma and form a diamond-like carbon film. Thereafter, a plurality of floating surface patterns 43 are formed on the row protection film. The formation of the air bearing surface pattern is performed using a photolithography technique. First, a plurality of rows are attached to a base plate, and a liquid resist is applied or a dry film resist in the form of a film is applied to the base plate. Next, processing is performed while leaving the mask surface by the ion milling method that processes by accelerated neutral ion collision or the reactive ion etching method that performs processing in plasma by introducing a reactive gas such as fluorine or chlorine. To obtain a plurality of floating surface patterns. Thereafter, the row is cut and separated into individual magnetic head sliders 21 (FIG. 12C).

With the recent increase in recording density, the flying height has been reduced for the purpose of improving the recording and reproducing efficiency. Recently, a magnetic head slider having a flying height of 0.05 μm or less has been put to practical use. . Along with this, the thickness of the protective film 39 formed on the magnetic head slider also increases
, Which is a value equivalent to 10 to 20% or more, which cannot be ignored (FIG. 14). For this reason,
Although the thickness of the protective film is being reduced by improving the abrasion resistance, at present the desired abrasion resistance has not been obtained.

[0007]

However, in the above-mentioned prior art, since the thickness of the protective film formed on the magnetic head slider substantially increases the flying height, the recording / reproducing efficiency is reduced. There is a problem, and there is a problem that it is desired to maintain sufficient CSS durability and to improve the reproduction efficiency by reducing the thickness of the protective film. On the other hand, Japanese Unexamined Patent Publication
No. 180354 discloses a technique for increasing the recording / reproducing efficiency by reducing the thickness of the protective film near the magnetic head element, but does not disclose a specific method for forming the protective film. Further, in the structure as disclosed in Japanese Patent Application Laid-Open No. 8-180354, there is a problem that the protective film thickness is maximum at the air inflow end, and the durability near the center where sliding with the disk-shaped storage medium occurs is insufficient. Was.

[0008] In order to solve the above problems, an object of the present invention is to provide a magnetic head slider that maintains sufficient CSS durability and has good recording and reproducing characteristics, and a method of manufacturing the same.

[0009]

In order to achieve the above object, the present invention provides a method of forming a protective film on a material having a lower conductivity than a material of a magnetic head slider near a magnetic head element. Thus, a magnetic head slider having a thin protective film only near the magnetic head was obtained. In addition, a material having a lower conductivity than the material of the magnetic head slider is disposed near both the air outflow end and the air inflow end of the magnetic head slider to form a protective film. The magnetic head slider has a thinner protective film and a thicker central protective film. .

As in the present invention, if a material having a lower conductivity than the material of the magnetic head slider is disposed in the vicinity of the magnetic head element of the magnetic head slider at the time of film formation, the portion does not function as an electrode. Only the plasma density near the magnetic head element decreases. Therefore, the film forming rate is reduced only in the vicinity thereof, and the film thickness can be reduced only in the vicinity of the magnetic head element. Similarly, when a material having a lower conductivity than the material of the magnetic head slider is disposed at both the air outflow end and the air inflow end of the magnetic head slider, the protective films at the air outflow end and the air inflow end are thinned, and the central portion is formed. It can be thicker.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a magnetic head slider, comprising: forming a protective film on the air bearing surface after disposing a material having lower conductivity than the material of the magnetic head slider near the magnetic head element.

[0012]

【Example】

(Embodiment 1) Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a thickness distribution of a protective film formed according to the present invention. The protective film is thin near the outflow end of the magnetic head slider where the magnetic head element is located, and becomes thicker inward. The thickness becomes thinner again near the outflow end, but this is because the low conductivity material is also arranged near the outflow end to form a film. Next, a method for obtaining such a thickness distribution of the protective film will be described in the order of steps with reference to FIG. A row 1 obtained by cutting a substrate on which a number of magnetic head elements are formed is lapped to a predetermined magnetic head height, and then aligned with the surface on which a protective film is formed, that is, the floating surface 3 facing down. Arrange on plate 5. Dummy members 7 which do not function as a magnetic head slider are arranged at both ends. In this case, the influence of the edge does not affect the row 1. FIG. 2A shows a state in which the components are arranged on the alignment plate 5. Since the size of the gap between rows is one of the factors that determine the thickness of the protective film on the magnetic head element, the gap must be constant. For this purpose, the alignment plate 5 has a groove 11 in which the row 1 is designed to fit. Subsequently, the base plate 15 coated with the positive photoresist 13 is placed over the aligned rows 1 and closely attached thereto (FIG. 2B). Since the base plate 15 is used as it is for forming the protective film, a conductive material, for example, a metal such as aluminum is selected.

The photoresist 13 develops an adhesive force as the solvent evaporates, but becomes so adhesive that the row 1 does not easily move in one or two minutes. afterwards,
The whole is turned over, the alignment plate 5 is removed, and the photoresist 13 is baked. The firing conditions vary depending on the type of photoresist, but in the example using OFPR800 manufactured by Tokyo Ohka, firing is performed at 90 ° C. for about 30 minutes using a heating furnace. After taking out from the heating furnace, the gap between the rows is filled by pouring the positive type photoresist 13 from the side again (FIG. 2C). Then put it in the heating furnace again,
For example, firing at 90 ° C. for about 1 hour. Thus, the rows are aligned, and the surface on which the protective film is formed on the base plate 15,
That is, the air bearing surface 3 is bonded with the air bearing surface 3 exposed.
Here, ultraviolet rays are irradiated in the short direction of row 1 and obliquely to the air bearing surface (FIG. 2D). In this way, the ultraviolet rays are not irradiated to the gap between the rows and are irradiated only to the photoresist that has protruded to the row surface. Only the photoresist remains (see FIG. 2).
(E)).

After the sputtered layer on the base plate 15 is formed by sputtering 2 nm of Si, SiC or the like as an intermediate layer, it is attached to the electrode 17 of the plasma CVD apparatus shown in FIG. A carbon film is formed to a thickness of 8 nm. 70 is applied to the electrode 17 of the CVD apparatus.
A negative DC high voltage of 0 V to 1000 V is applied to induce plasma to form a film. CH4, C2H as material gas
6, a hydrocarbon gas such as C6H6 is used.

FIG. 4 is a diagram showing a plasma density distribution near the row surface. Since a photoresist having low conductivity is buried between the rows, the plasma density thereon is reduced. Therefore, the frequency of the ionized material gas incident on the row surface is lower than that of the surrounding area, and the film forming rate is reduced. As a result, the film thickness becomes thinner near the end than in the center of the row. The reduction in plasma density varies depending on the row spacing, the thickness of the photoresist, the conductivity, the dielectric constant, and the like. By adjusting these, a desired thickness distribution of the protective film can be obtained. The rate at which the edges become thinner depends on the voltage applied to the electrodes and the material gas pressure,
In the example in which a voltage of 0 V was applied and CH4 was used as the material gas, the ratio of the film thickness near the edge to the film thickness near the center showed dependency on the row spacing as shown in FIG. The thickness of the photoresist in the height direction can be adjusted by changing the irradiation angle of ultraviolet rays. When the irradiation angle is increased with respect to the air bearing surface, the ultraviolet rays are irradiated to the depth of the gap between the rows, and the photoresist thickness is reduced. Conversely, if the angle is reduced, the photoresist thickness can be increased.

In the above example, OFPR800 manufactured by Tokyo Ohka was used as the photoresist. However, it is needless to say that other positive photoresists such as AZ series manufactured by Hoechst may be used. That is. It is apparent that the same effects can be obtained by applying the method of the present invention under other conditions for the material gas, the voltage applied to the electrodes, and the like.

A CSS durability test was performed using the magnetic head slider obtained according to the present invention. The result is shown in FIG.
Shown in In the magnetic head slider according to the method of the present invention, a magnetic head slider having a protective film formed by a conventional method and a CS
S durability was obtained. When the linear output density dependency of the reproduction output was measured, a result as shown in FIG. 7 was obtained. Although the flying height was the same in the magnetic head slider according to the present invention, a higher reproduction output was obtained as compared with the magnetic head slider according to the conventional method, and it was found that it could be used up to a higher linear recording density.

(Embodiment 2) Next, another embodiment will be described. In the above-described example, an example in which the protective film is formed in a row state is shown. Here, a method of forming a protective film after forming an air bearing surface pattern on a row and cutting the magnetic head slider alone will be described.

FIG. 8 is a diagram showing a film thickness distribution of the protective film obtained according to this embodiment. Not only in the longitudinal direction but also in the lateral direction of the magnetic head slider, a thin film thickness distribution is obtained at the end portions and at the center portion.

A method for obtaining such a film thickness distribution will be described below. A row obtained by cutting a substrate on which a number of magnetic head elements are formed is wrapped to a predetermined magnetic head height, the air bearing surface pattern is etched, and then cut into individual magnetic head sliders. Processed. The magnetic head sliders 21 thus obtained are arranged on the slider alignment plate 23 with the floating surface facing down.
At this time, a slider dummy member 25 is disposed at the end to eliminate the influence of the end. This situation is shown in FIG. As described above, the size of the interval between the magnetic head sliders is one of the factors that determine the thickness of the protective film at the end of the magnetic head slider. The magnetic head sliders 21 are designed so as to be aligned at regular intervals. Subsequently, the base plate 15 coated with a positive photoresist is placed over and adhered to the aligned magnetic head slider 21. Since the base plate 15 is used as it is for forming the protective film, a conductive material, for example, a metal such as aluminum is selected as in the first embodiment.

After baking in the same manner as in the first embodiment, after pouring and re-baking a photoresist, ultraviolet rays are applied diagonally to the magnetic head slider 21 and obliquely to the air bearing surface (FIG. 9B). ). In this case, the ultraviolet rays are not irradiated between the magnetic head sliders but are applied only to the photoresist which has protruded to the surface of the magnetic head slider, and when developed, the photoresist which has protruded to the surface of the magnetic head slider is removed. The photoresist remains only in the gap between the head slider (FIG. 9).
(C)). An intermediate layer and a protective film are formed on the magnetic head slider 21 attached to the base plate 15 as in the first embodiment.

[0022]

As described above, according to the present invention, the protective film of the magnetic head element portion of the magnetic head slider can be formed to be thin and the central portion thereof to be thickly distributed.
There is an effect that the recording / reproducing characteristics can be improved without lowering the S durability. In addition, since the flying surface can be made convex by using only the protective film, a stable convex shape is realized, and the floating characteristics, C
There is an effect that a magnetic head slider that is stable in both SS durability can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing a thickness distribution of a protective film of a magnetic head slider when a protective film is formed on a row by a method according to the present invention.

FIG. 2 is an explanatory view illustrating a method for forming a protective film according to the present invention.

FIG. 3 shows a plasma C used for forming a protective film according to the present invention.
FIG. 4 is an explanatory diagram illustrating a VD device.

FIG. 4 is a diagram showing a plasma density distribution when forming a protective film according to the present invention.

FIG. 5 is an explanatory diagram showing how the ratio of the thickness of the protective film on the magnetic head element to the thickness of the protective film at the center of the row changes depending on the row interval in forming the protective film according to the present invention.

FIG. 6 is a diagram showing a CSS durability test result of the magnetic head slider according to the present invention.

FIG. 7 is a diagram showing the linear recording density dependence of the reproduction output of the magnetic head slider according to the present invention.

FIG. 8 is a diagram showing a distribution of a protective film thickness when a protective film is formed on a magnetic head slider alone by the method according to the present invention.

FIG. 9 is an explanatory diagram for explaining a method of forming a protective film on a magnetic head slider alone according to the present invention.

FIG. 10 is a diagram showing a magnetic disk drive.

FIG. 11 is an explanatory diagram showing a state when a magnetic head slider is rotating and when rotation is stopped by a conventional method.

FIG. 12 is an explanatory diagram for explaining a processing step of the magnetic head slider.

FIG. 13 is a view showing a plasma CVD apparatus for forming a protective film by a conventional method.

FIG. 14 is an explanatory diagram illustrating a relationship between a flying height and a protective film thickness.

[Explanation of symbols]

 Reference Signs List 1 row 3 flying surface 5 alignment plate 7 dummy member 9 magnetic head element 11 groove 13 photoresist 15 base plate 17 electrode 19 material gas 21 magnetic head slider 23 alignment plate for slider 25 slider dummy member 27 disk-shaped recording medium 29 actuator 31 spindle Motor 33 Signal processing circuit 35 Head suspension mechanism 37 Crown 39 Protective film 41 Substrate 43 Flying surface pattern 45 Flying amount

Claims (7)

[Claims] 1. A method of manufacturing a magnetic head slider, comprising: disposing a material having a lower conductivity than the material of the magnetic head slider in the vicinity of the magnetic head element; 2. The method of manufacturing a magnetic head slider according to claim 1, wherein the low conductive material is a photoresist. 3. The method of manufacturing a magnetic head slider according to claim 1, wherein said protective film is a diamond-like carbon film. 4. A magnetic head slider having a thin protective film at both an air inflow end and an air outflow end and a thick central portion. 5. The magnetic head slider according to claim 4, wherein said protective film is a diamond-like carbon film. 6. A method of manufacturing a magnetic head slider, comprising: forming a protective film on an air bearing surface after disposing a material having lower conductivity than that of a magnetic head slider at both an air inflow end and an air outflow end. Method. 7. The method of manufacturing a magnetic head slider according to claim 4, wherein the low conductive material is a photoresist.