JP2002133630A - Magnetic head and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head slider, which is for a high-density- recording magnetic disk device, having a low adhesion to magnetic disk. SOLUTION: This magnetic disk is manufactured by forming a carbon-based protective coat on the surface of a face opposed to the medium of a slider material consisting of a binary system or more components system material. In this case, a single-layer filler which exists on the surface of the slider on which the carbon-based protective coat has not yet been formed is oxidized and swelled to form a projection which makes the surface rough. An area to be roughened on the surface of the slider is designed, the single-layer filler forms the projection, and at the same time the distortion by the processing is induced on the surface of the slider by the cubical expansion of the filler in the direction of the face of the slider, and thereby the plane of the face opposing to the medium is controlled. It is possible, therefore, to manufacture the magnetic head slider which can inhibit the adhesion of the surface of the lifted slider, electric discharge and corrosion, precisely and good in mass- productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetic head used as a magnetic recording device in combination with a magnetic disk.

[0002]

2. Description of the Related Art Along with an increase in the amount of information, a magnetic disk device is required to have a higher recording density, and as the areal recording density is improved, a demand for higher performance of a thin film magnetic head element and a lower flying height of a head slider is required. Is also getting tougher. For this purpose, MR (Magneto-Resis) capable of reading with high sensitivity
tive) Further technical innovations are indispensable for the inductive composite element and the head slider surface serving as the air bearing surface in order to prevent corrosion of the head magnetic film and to improve the sliding resistance due to the low flying height.

In the current magnetic disk device, the magnetic disk starts rotating at the time of start-up, and when a certain speed is reached, the magnetic head receives the floating and floats at a fixed flying height to perform recording and reproduction.
At the time of stop, the rotational speed of the magnetic disk decreases, the flying height of the magnetic head gradually decreases, and the magnetic head comes into contact with the magnetic disk and stops. This method is called contact start stop (CSS). At present, a flying height of 0.1 μm or less has been achieved by the CSS method. This C
In the SS method, when the CSS is repeated, when the magnetic head comes into contact with the magnetic disk and slips, the flying surface of the magnetic head is worn. When the wear occurs, the magnetic head element portion is easily discharged or corroded. In order to prevent abrasion, there is a method of applying a lubricant on the magnetic disk, but on the other hand, this lubricant causes the magnetic head that is stopped and the magnetic disk to adhere to each other. Therefore, in order to prevent sticking, the surface of the magnetic disk is textured to reduce the true contact area between the magnetic head and the magnetic disk.

However, in recent years, from the viewpoint of reducing the flying height, a smooth disk which is not subjected to texture processing is being used in an area for recording and reproducing data.
In this smooth disk, no texture is formed except in the CSS zone on the disk surface. For this reason,
The head is CS due to vibration from HDD assembly or from outside.
If the head stops on the data zone, for example, if the head has returned to the CSS zone for some reason during the stop operation when the head has moved from the S zone to the data zone, the contact area between the magnetic head and the magnetic disk is reduced. There was a problem that it was easy to stick because it was large.

Therefore, in a CSS test which is a standard life test of a magnetic disk, in order to improve the durability operation characteristics, various companies have applied a technique of making the flying surface of the head a convex portion. This can greatly contribute to preventing the head from sticking due to the lubricant interposed between the magnetic disk and the head. For example, a method called touch lap, in which a convex portion is formed by mechanically polishing the head air bearing surface, and in Japanese Patent Publication No. 7-82631, a groove is formed on the head air bearing surface by mechanically leaving a processing mark, whereby the processing is performed. There is a method of inducing distortion and forming a convex part.Either method is effectively used to improve the operating characteristics, but in the future, as the magnetic head flying height further decreases, this method will improve durability. The effect of is becoming imperfect. On the other hand, in order to solve such a problem, as a means for roughening the slider rail surface of the head, there is a method of embedding a solid or liquid lubricant in a concave portion thereof. No. 2,767,695.
However, in these methods, when forming a recess in a difficult-to-work material such as alumina titanium carbide or zirconia serving as a slider base material, a corrosive medium is used, causing corrosion of the head element itself, which is not practical. .

Further, a projection-forming material such as carbon is formed on the slider rail surface of the head, which is hard to be worn, and the film is dry-etched through a mask having a projection pattern formed thereon, thereby forming a portion other than the area covered by the mask. Is completely removed to form a projection having a shape corresponding to the mask pattern. As a technique related to this, for example, Japanese Patent Application Laid-Open No. 8-69674 and the like can be mentioned. However, according to these methods, the ceramic material as the head member or the adhesive layer between the ceramic material and the carbon film is exposed on the side wall and the rail surface of the projection. If the ceramic is exposed, it is likely to cause a crash due to contact with the disk, and if the adhesive layer is exposed, the adhesive layer will wear due to contact with the disk and the projections will peel off, As described above, there is a problem that the ceramic under the adhesive layer is exposed and causes a crash.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and has at least a projection on a slider surface, and if a projection formation region is designed, the head floating surface shape can be improved. It is also possible to use a convex part,
An improved slider structure that can dramatically increase the reliability of conventional sliders, and its manufacturing method, that is, a protrusion that enables adhesion, discharge, and corrosion prevention to the slider air bearing surface is accurately and mass-produced. An object of the present invention is to provide an improved slider manufacturing method which can be formed well.

[0008]

As a result of examining the projections formed on the slider floating surface and the shape of the floating surface using several forming means, the single layer filler on the slider surface is oxidized and expanded in volume with good controllability. I was able to find that. Specific forming means will be described below. First, Al ₂ O ₃ TiC (Al
_{2 O 3: 40%, TiC} : was studied magnetic head using the 60%). As a pretreatment, an a-Si film was deposited to a thickness of about 1 to 10 nm on the Al ₂ O ₃ portion in which the element portion was embedded to protect the head element portion. Thereafter, in order to oxidize the slider surface excluding the element portion, the TiC-only filler portion was oxidized by RIE using oxygen to expand the volume. The projection height at this time is determined by the processing time,
Accurate control was possible using discharge power, oxygen gas flow rate, and the like. Other oxidation methods (thermal oxidation method, local thermal oxidation method using excimer laser, polishing method using an oxidizing agent) described in the claims were also examined, but any method was possible. Although a method combining these oxidation methods was also studied, a combination of appropriate heating and oxygen RIE treatment could control the height of the projections with high accuracy.

The height of the protrusion to be controlled is determined from the relationship of the flying height on the magnetic disk surface, and is preferably 30 degrees.
Processing was performed taking into account 〜50 nm. After this treatment, an adhesive layer a-Si film of an ABS protective film is formed on the slider surface by 0.5 to 3 mm.
As an ABS protective film, a carbon-based thin film of 3 to 20 nm, such as conventionally known amorphous carbon or diamond-like carbon, was formed.

It has also been confirmed that the convex shape of the slider floating surface can be controlled by changing the projection forming area on the slider floating surface. Conversely, when the protrusions are formed only in local portions (for example, only in three regions of the slider surface), the floating surface shape does not change significantly.

[0011] The slider is a slider material composed of two or more binary materials and having an oxidizable filler.
This processing is possible. For example, AlTiC (Al ₂ O ₃ +
A magnetic head characterized by using any one of TiC), zirconia, calcium titanate, α-hematite and SiC has already been examined, and similar effects have been obtained.

[0012]

FIG. 1 shows an embodiment of the present invention.

FIG. 1A is a schematic sectional view of an AlTiC slider block 1. In this figure, titanium carbide (TiC) 3 embedded in alumina (Al ₂ O ₃ ) 2 as a filler can be confirmed. In the present invention, titanium carbide (TiO ₂ ) is arbitrarily arbitrarily formed by chemically oxidizing the titanium carbide filler 3 scattered mainly on the surface on the side of the A surface serving as the slider floating surface.
The point is to form 4. By oxidizing, the projection and the distortion in the slider surface direction are formed in expectation of volume expansion as a filler. As the method of the oxidation treatment, a thermal oxidation treatment of the TiC surface, a plasma oxidation treatment by RIE or the like using oxygen, a thermal oxidation treatment by local heating using an excimer laser, a chromium agent, etc. There is a polishing treatment using an oxidizing agent such as a low-concentration hydrogen peroxide solution. FIG. 1B shows a cross-sectional view of the slider block after the oxidation treatment.
It can be seen that the titanium carbide fillers 3 scattered on the surface on the A side become titanium oxide 4 and protrude to form protrusions. Also, due to the volume expansion of the filler itself, FIG.
As shown in (b), a convex distortion of the slider block is also formed. However, the distortion can be increased or decreased by designing an oxidized region. Next, FIG.
In the above, the floating surface protection film 5 is formed on the formed slider floating surface with projections. As the air bearing surface protection film 5, a carbon-based thin film such as amorphous carbon or diamond-like carbon is formed. In particular, a method using a CVD method with good coverage is better as a manufacturing method. FIG. 2 is a schematic external view of the magnetic head 9 thus formed.
Shown in The head element section 6 in FIG. ₂ has an a-Si film of about 1 to 10 nm on the Al ₂ O ₃ portion in which the element section is embedded to protect the head element section 6 during the processing of FIG. Has been deposited. In this embodiment, the protrusions are formed only on the floating surface 8 of the slider rail 7.

FIG. 3 shows the result of observing the state of the slider rail 7 surface before and after the oxidation treatment with an atomic force microscope. FIG. 3A shows the state before the oxidation treatment, and FIG. 3B shows the state after the oxidation treatment. Here, as the oxidation treatment method, a method of simultaneously performing heating and oxygen plasma ashing was adopted. The heating temperature was about 120 ° C., and the oxygen plasma processing conditions were RF power of 300 W and argon gas pressure of 66.7 Pa (0.5 Torr). Comparing the photographs before and after the treatment in FIG. 3, the surface state after the treatment can clearly be observed in a state where the filler portion is expanded in volume and raised. The average height of the projections in this photograph is about 30 nm, but the height of the projections can be arbitrarily selected by changing the oxidation processing conditions or controlling the processing time. FIG. 4 shows the results of observation using a scanning electron microscope. Fig. 4 (a-1), (a-2)
Fig. 4 (b-1) and (b-2) show the cross-sectional profile of the unprocessed substrate and the photograph taken from the front, respectively. 3) is a cross-sectional profile and an observation photograph from the front.
From this photograph, it can be confirmed that the filler portions are formed as protrusions.

Next, FIGS. 5 and 6 show how the height of the protrusion can be controlled by the oxidation treatment method when the protrusion of the filler is formed. FIG. 5 shows that the oxygen plasma processing conditions are constant (RF power 500 W, argon gas pressure 66.7 Pa).
(0.5 Torr)) and the result when the processing time is arbitrarily changed. According to this result, it can be confirmed that the average height of the projections tends to increase by increasing the processing time. From this relationship, it was found that the projections having an arbitrary height can be formed with good controllability. On the other hand, FIG. 6 shows the results when the thermal oxidation processing conditions (oxygen introduction amount, processing time) are constant and the heat processing temperature is arbitrary. Also in the present results, it can be confirmed that increasing the heating temperature increases the average height of the protrusions, and it can be seen that the formation of protrusions of any height can be controlled with good controllability.

The case where the protrusion formed as described above was designed in a pattern of the protrusion 8 as shown in FIG. 7 was examined. For the pattern formation, an oxidation treatment is performed through a mask having a similar design. In this pattern,
Since the projection formation area is as small as 10% or less of the surface area of the slider rail 7, the slider itself does not greatly deform. A diamond-like carbon thin film is formed on the slider surface thus formed as a floating surface protection film to a thickness of 10 nm by using a CVD method having good coverage, and
The adhesion of the S-type slider to the magnetic disk was studied. In this embodiment, the total area of the projections 8 is 0.01 mm ² and the height is 10 to 10 mm from the rail surface.
A study was performed for 50 nm. Surface roughness Rp is about 7n
When the initial maximum adhesive strength was measured on a smooth disk coated with a lubricant of 2 nm on a disk of m, the result as shown in FIG. 8 was obtained. It was found that the slider having the projections 8 according to the present example had an initial maximum adhesive strength of about 3 gf at a projection height of 30 nm or more.

In the method of oxidizing the partial flying surface of the head as shown in FIG. 7, a large distortion of the slider body is not induced, but, for example, as shown in FIG. By oxidizing a region such as the entire surface of the slider floating surface, distortion of the slider itself can be induced. This is called a touch wrap in the prior art, a method of mechanically polishing the head air bearing surface to form a convex portion, or mechanically leaving a groove on the head air bearing surface to form a processing mark, thereby inducing a processing distortion. The same effect as the method of forming the portion, that is, the reduction in the adhesive strength as described above can be expected. That is, by oxidizing, not only the formation of filler protrusions for roughening the slider surface, but also the slider itself can be formed into a convex shape that is less likely to cause sticking. FIG. 9 (a) shows an AlTiC substrate (not a patterned head element) before processing on a non-contact optical interference type surface profiler (WYKO).
FIG. 9 (b) shows a three-dimensional view of the same substrate after thermal oxidation treatment, and FIG. 9 (a), (b) As is clear from the comparison, distortion is induced by using the surface subjected to the oxidation treatment as a convex portion. As for the amount of deformation, it was confirmed that the amount of deformation was larger in the longitudinal direction of the substrate than in the shorter direction. Of course, the amount of deformation of the distortion can be variously changed by designing the oxidized region of the slider surface. FIG. 9C shows a head element obtained by using a thermal oxidation process on an AlTiC substrate patterned as a head element. FIG. 10 shows the magnitude of these obtained deformation amounts. By changing the thermal oxidation treatment time from the result of this embodiment, the flatness deformation amount PV value is 0 to 15
About 0 nm could be confirmed. In this example,
The magnetic head according to claim 3, wherein the height of the protrusion is 3 to 50 nm, since the difference in PV value can be confirmed even under the condition that the filler protrusion is about 3 nm. It refers to the manufacturing method.

FIG. 11 shows the configuration of a magnetic disk drive on which the magnetic head of the present invention is mounted. The magnetic head slider 9 is attached to a suspension 10 and is incorporated so that the slider rail surface faces the magnetic disk 11.

[0019]

According to the present invention, as the areal recording density is improved in the future, the thin film magnetic head slider is made to adhere to the slider floating surface and to prevent discharge and corrosion due to the low flying height of the slider. An improved slider that has at least a protrusion on the slider surface and can form a protrusion on the head floating surface if the protrusion formation region is designed, which can dramatically improve the reliability of a conventional slider Provided is a structure and a method of manufacturing the same (forming projections with high accuracy and high productivity). Further, according to the present invention, it is possible to greatly reduce the slider surface processing of the downsized ultra-small magnetic head.

Further, according to the method of manufacturing a magnetic head slider of the present invention, a magnetic head slider capable of greatly reducing the initial adhesive force on a disk can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view of a manufacturing process of an embodiment of the present invention.

FIG. 2 is a schematic diagram of an MR magnetic head to which the present invention is applied.

FIG. 3 is a diagram showing a result of observing a slider surface of a magnetic head before and after the present invention by an atomic force microscope.

FIG. 4 is a diagram showing a result of observing a slider surface of a magnetic head before and after the implementation of the present invention with a scanning electron microscope.

FIG. 5 is a diagram showing experimental results of oxygen plasma processing time and average projection height when the present invention is implemented.

FIG. 6 is a diagram showing experimental results of a thermal oxidation treatment temperature and an average projection height when the present invention is carried out.

FIG. 7 is a schematic diagram of an MR magnetic head slider surface to which the present invention is applied.

FIG. 8 is a view showing an experimental result of a projection height and an adhesive force between a head and a disk of an MR magnetic head embodying the present invention.

FIG. 9 is a view showing the results of observing a slider substrate before and after the present invention and a magnetic head surface after the present invention by a non-contact light interference type surface shape measuring instrument.

FIG. 10 is a diagram showing experimental results of thermal oxidation treatment time and head plane deformation (PV) when the present invention is carried out.

FIG. 11 is a schematic diagram of a magnetic disk drive using a magnetic head to which the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate for magnetic heads, 2 ... Alumina material, 3 ... Titanium carbide material, 4 ... Titanium oxide, 5 ... Floating surface protection film, 6 ...
Magnetic element portion, 7: slider rail portion, 8: protrusion forming region, 9: magnetic head, 10: suspension, 11: magnetic disk.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G11B 21/21 101 G11B 21/21 101L (72) Inventor Shigehiko Fujimaki 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Stock (72) Inventor Eiichi Kashiwase 1-280 Higashi-Koigakubo, Kokubunji-shi, Tokyo Tokyo, Japan Inside (72) Inventor Norio Nakagawa 2880 Kozu, Kodahara, Kanagawa Prefecture F term in the system division (reference) 5D042 NA02 PA01 PA05 PA09 QA03 RA02 SA03 5D111 AA24 DD04 DD24 EE02 FF14 GG09 HH08 JJ08 KK09

Claims (10)

[Claims] 1. A magnetic head manufactured by forming a carbon-based protective film on a surface serving as a medium facing surface of a slider material made of a binary material or more, which exists on the slider surface before the carbon-based protective film is formed. A magnetic head characterized in that the surface is roughened by forming a single-layer filler as a projection, and a method of manufacturing the same. 2. The slider according to claim 1, wherein the surface of the slider is designed so as to roughen the surface of the slider. A magnetic head and a method of manufacturing the same, wherein the planar shape of the medium facing surface is controlled by inducing distortion. 3. The method according to claim 1, wherein the height of the protrusion is 3
A magnetic head having a thickness of about 50 nm and a method of manufacturing the same. 4. The magnetic head according to claim 1, wherein at least one of AlTiC (Al ₂ O ₃ + TiC), zirconia, calcium titanate, α-hematite, and SiC is used as the slider material. 5. The magnetic head according to claim 1, wherein a C film, a C—H film, and a C—N film are used as the carbon-based protection film, and a method of manufacturing the same. 6. A means for realizing the single layer filler according to claim 1, 2 or 3, wherein at least the single layer is oxidized,
For example, by thermally oxidizing the TiC surface,
_2. A magnetic head in which filler protrusions are formed by volume expansion, and a method of manufacturing the same. 7. A means for realizing the single layer filler according to claim 1, 2 or 3, wherein at least the single layer is oxidized by RIE using oxygen, for example, TiC is converted into TiO ₂ to generate protrusions and volume expansion. And a method of manufacturing the same. 8. A means for realizing the single-layer filler according to claim 1, 2 or 3, wherein at least the single layer is thermally oxidized by local heating using an excimer laser.
A magnetic head formed by using iC as TiO ₂ to generate protrusions and volume expansion, and a method of manufacturing the same. 9. As means for realizing the single layer filler according to claim 1, at least when the single layer is polished, an oxidizing agent such as chromic acid or low-concentration hydrogen peroxide is used at the same time. And a magnetic head formed by applying a polishing method that oxidizes and expands a high-hardness filler with good controllability and leaves it as a protrusion, and a method of manufacturing the same. 10. A magnetic disk drive using the magnetic head according to claim 1 and a method for manufacturing the same.