JPH0830944A - Production of magnetic head device - Google Patents

Abstract

PURPOSE:To make a floating amount low, to suppress generation of stiction phenomenon and to improve the yield of production. CONSTITUTION:This process for producing a magnetic head device comprises forming a thin-film magnetic head element 16 on one main surface of a slider 15 in such a manner that a magnetic gap (g) is faced to a contact surface with a magnetic recording medium. The thin-film magnetic head elements 16 formed in a plurality on a wafer 1 are cut to a rectangular shape and the rear surface on the side opposite to the medium-contact surface of the cut head element block 3 is subjected to powder beam etching and thereafter, the medium-contact surface of the head element block is formed to a prescribed shape by powder beam etching.

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 device suitable for recording / reproducing on / from a magnetic recording medium such as a hard disk or a floppy disk.

[0002]

2. Description of the Related Art For example, a magnetic head device mounted in a hard disk drive device includes a recording head using an inductive thin film magnetic head (hereinafter referred to as an inductive head) and a magnetoresistive effect magnetic head (hereinafter referred to as a magnetic head) having excellent short wavelength sensitivity. , MR head) and a reproducing head.

An example of such a magnetic head is Al ₂
On the slider made of O ₃ -TiC or the like, the reproducing magnetic gap is formed facing the hard disk contact surface, that is, the ABS (air bearing surface) surface.
The R head and the inductive head forming the recording magnetic gap are laminated by a vacuum thin film forming technique.

The MR head is composed of a magnetoresistive effect element (hereinafter referred to as an MR element) made of a magnetoresistive effect thin film in which electrodes are laminated at the front end portion and the rear end portion, for example, and a magnetized state in a direction required for the MR element. And a bias conductor for providing the MR element, and the MR element is sandwiched by a pair of shield magnetic bodies with an insulating layer interposed between them to form a so-called shield structure.

On the other hand, the inductive head is provided with a pair of recording cores forming a closed magnetic path and a recording coil provided between the recording cores, and the magnetic recording medium faces the ABS surface between the front end portions of these recording cores. It is structured to form a gap.

In order to manufacture the magnetic head having the above-mentioned structure, first, the MR head and the inductive head are sequentially laminated and formed on the substantially disk-shaped wafer made of Al ₂ O ₃ --TiC or the like by the vacuum thin film forming means. . These M
A plurality of thin film magnetic head elements formed by laminating an R head and an inductive head are formed on a wafer at predetermined intervals so that a few rows are formed. Then, each thin film magnetic head element is cut into blocks so that the plurality of thin film magnetic head elements are aligned in the longitudinal direction to form a strip-shaped head element block.

Next, the strip-shaped head element block is bonded to a predetermined jig by using wax so that the gap depth of each thin film magnetic head element becomes a predetermined value.
The ABS surface which is the medium contact surface of the head element block is depth-polished.

After that, a resist pattern for rail processing is formed on the ABS surface. Then, using the resist pattern as a mask, rail processing is performed on the ABS surface by a powder beam etching processing method in which fine particles such as SiC are sprayed onto the sample at high speed to perform fine processing.

Next, the head element block is cut into individual sliders and attached to the suspension to complete a magnetic head device for a hard disk.

In the magnetic head device thus completed, signals are recorded and reproduced by levitating on the rotating magnetic recording medium.

[0011]

By the way, in the hard disk storage device, in order to increase the recording density, it is required to reduce the flying height of the slider and to keep the flying height constant over the entire data zone. In order to realize this, it is necessary to make the ABS surface formed on the slider surface into a free shape. The free shape means that the rail formed on the ABS surface is not a straight shape but has a triangular shape or a shape including a curved shape.

It is impossible to form the ABS surface into a free shape by conventional machining, and examples of the processing method include powder beam etching processing and vacuum etching such as ion milling.

However, even in a slider having a free shape, it is necessary to control the curvature or surface shape of the ABS surface with high accuracy in order to realize a flying height as low as 0.1 μm or less. In other words, the flying height of the slider is AB
This is because it depends on the shape of the S surface. Further, since many of the current storage devices adopt the contact start stop system (CSS system) when the storage device is activated, it is desired to improve durability against sliding between head media.

In order to suppress wear due to sliding, the sliding time may be shortened. For that purpose, a suitable convex shape with respect to the medium (hereinafter referred to as a regular crown shape).
Is desirable. Further, the sticking phenomenon (stiction) between the media and the slider may occur as a trouble. It is said that the provision of a regular crown shape is also effective for preventing this.

By the way, when rail processing by powder beam etching processing is applied to the ABS surface, the processing stress generated by the processing remains in the slider, so that an appropriate regular crown shape cannot be obtained. Therefore, it becomes difficult to achieve the problem of stiction and the reduction of the flying height.

Therefore, the present invention has been proposed in view of the above-mentioned conventional problems, and it is possible to reduce the flying height and suppress the occurrence of the stiction phenomenon, and to improve the manufacturing yield of a magnetic head device. It is intended to provide a manufacturing method.

[0017]

SUMMARY OF THE INVENTION The present invention is a method of manufacturing a magnetic head device in which a thin film magnetic head element is formed on one principal surface of a slider so that a magnetic gap faces a surface facing a magnetic recording medium. In, a plurality of thin film magnetic head elements formed on the wafer are cut into strips, and the back surface of the cut head element blocks opposite to the medium-contacting surface is subjected to powder beam etching or mechanical grinding or After mechanical polishing is performed, the above-mentioned problem is solved by forming the medium contact surface of the head element block into a predetermined shape by powder beam etching.

[0018]

In the present invention, when powder beam etching is performed on the medium-facing surface facing the magnetic recording medium, processing stress remains in the head element block. This is due to powder beam etching or mechanical grinding on the opposite back surface. By performing the processing or the like, the processing stress on the back surface cancels the total processing stress when the medium contact surface is processed. As a result, the block shape change amount is controlled to zero or an appropriate positive convex amount.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments to which the present invention is applied will be described in detail below with reference to the drawings.

First, an MR head dedicated to reproduction and an inductive head dedicated to recording are sequentially laminated on a wafer having a substantially disk shape made of Al ₂ O ₃ --TiC or the like by vacuum thin film forming means, and the thin film magnetic head element is formed. A plurality of rows are formed at predetermined intervals so as to form several rows and several columns.

Next, as shown in FIG.
To the main surface of the cutting block 2.

Then, a strip-shaped head element block 3 is formed by cutting the wafer 1 block by row so that a plurality of thin film magnetic head elements are arranged in the longitudinal direction.

Next, these head element blocks 3 are removed from the cutting block 2 and washed.

Next, the ABS of the head element block 3 is
Powder beam etching is performed on the back surface opposite to the surface. The powder beam etching processing is a processing method characterized in that, for example, fine particles having an average particle diameter of 1 to 7 μm, such as SiC, are sprayed onto a sample at a high speed, and even hard materials such as ceramics can be finely processed. . Here, the shape is not processed on the back surface of the head element block 3, but is performed for the purpose of canceling the processing stress when the rail processing is performed on the ABS surface in the process described later. Therefore, the processing conditions such as the abrasive grain size and the injection pressure are determined so that the final block shape change amount becomes a predetermined value.

In addition to this, the same effect can be obtained by performing mechanical grinding or mechanical polishing on the back surface of the head element block 3. These mechanical processes include, for example, a vertical grinding machine (so-called V polishing), a lens polishing machine, and the like.
The processing conditions include the method and the grain size of the abrasive grains used in the knife of the grinding machine or the polishing machine, and are determined so that the final block shape change amount becomes a predetermined value.

Next, as shown in FIG. 2, the head element block 3 is adhered to a dedicated block processing jig 4 using wax.

Then, the ABS surface, which is the medium contact surface, is ground by a vertical grinder or the like, and then the gap depth of the head element block 3 is ground to a predetermined depth.

Thereafter, the head element block 3 is removed from the block processing jig 4 and washed.

Next, as shown in FIG. 3, the plurality of head element blocks 3 are aligned on the substrate 5.

A of these head element blocks 3
As shown in FIG. 4, the sheet resist 6 is thermocompression-bonded to the BS surface.

Next, as shown in FIG. 5, a patterning mask 7 having a predetermined pattern is placed on the sheet resist 6, and then ultraviolet rays UV are irradiated from an exposure light source 8 to perform exposure.

After that, development is performed. Then, a resist mask for forming a free shape on the ABS surface is formed.

Next, as shown in FIG. 7, a head is formed by a powder beam etching method in which fine particles are sprayed at a high pressure from a nozzle 9 of a fine particle spraying processing device using the hardened resist mask 6 as a mask. Rail processing is performed on the surface of the element block 3 that is the ABS surface.

As a result, the ABS of the head element block 3 is
Rails 10, 11 and 12 having high dimensional accuracy are formed on the surface to be the surface, as shown in FIG.

Next, the resist mask 6 is peeled off and washed.

Next, these head element blocks 3 are
It adheres on the cutting jig 13 shown in FIG.

Then, the head element block 3 is cut by the diamond wheel 14 to manufacture the slider 15.

After that, each slider 15 is attached to the jig 1 for cutting.
Remove from 3 and wash.

As a result, as shown in FIG. 9, the thin-film magnetic head element 16 is formed on one main surface of the slider 15, and the magnetic gap g of the thin-film magnetic head element 16 faces the ABS surface 17. . In the magnetic head device thus formed, the processing stress when the ABS surface 17 is subjected to the powder beam etching processing is canceled by the processing stress due to the powder beam etching processing or the mechanical processing performed on the back surface, and is zero, or It is controlled to an appropriate positive convex amount.

The principle of this is as follows.
The amount of shape change of the block is determined by the adhesive stress due to the adhesive, the processing stress due to mechanical grinding or polishing, and the processing stress due to the powder beam etching processing. Currently, the stress of the adhesive is reduced to a negligible level. The processing stress due to mechanical grinding or polishing changes depending on the polishing method and the grain size of the abrasive grains, and at the same time, the surface roughness of the processed surface also changes.

In the slider processing step, a processing stress is generated on the processed surface of the block by grinding the ABS surface and the back surface. At this time, if the processing stress generated between the ABS surface and the back surface is different, the shape of the block changes. Correspondence can be made between the block shape change amount and the surface roughness.

FIG. 10 shows the relationship between the surface roughness Ra (center line average roughness) and the block shape change amount. For example,
When the processing conditions for the ABS surface are fixed (polishing with 1/4 μm abrasive grains), the surface roughness of the processed surface changes as the processing conditions for the back surface change. Further, the greater the surface roughness, the greater the warp of the block, with the front surface inside. This indicates that a work-affected layer is formed on the ABS surface by polishing the back surface, and a compressive stress acts therein.

Also in the powder beam etching processing, the processing stress applied to the processed surface changes with the change of the processing conditions. In conjunction with that, the surface roughness of the machined surface also changes. Processing conditions in the powder beam etching processing include abrasive grain size, injection pressure (nozzle pressure), and the like. The relationship between these parameters and the surface roughness of the machined surface is shown in Fig. 1.
As shown in FIG. 1 and FIG. 12, the surface roughness of the machined surface also increases as the particle size and the flow velocity increase. Along with that, the compressive stress generated in the work-affected layer also increases. As a result, as the grain size and flow velocity increase, the block shows a larger warp with the processed surface facing outward. 13 and 14 show the relationship between the abrasive grain size and the amount of block warpage. It can be seen that the amount of block warpage greatly increases as the particle size increases.

By using the above principle, the processing stress generated by the powder beam etching processing on the ABS surface is
Powder beam etching or mechanical grinding can be applied to the back surface to cancel the total processing stress applied to the block. As a result, the block shape change amount can be controlled to zero or an appropriate positive convex amount. After the powder beam etching process is completed, the block is cut, but it is determined by the curvature of each slider chip,
By controlling the amount of change in the shape of the block, the curvature of the ABS surface of the slider chip can be controlled.

[0045]

As is apparent from the above description, according to the method of manufacturing a magnetic head device according to the present invention, the back surface of the head element block opposite to the ABS surface is subjected to powder beam etching or mechanical grinding. Since processing or mechanical polishing is performed, the processing stress generated by powder beam etching processing on the ABS surface is canceled by the processing stress generated on this back surface, and the block shape change amount becomes zero or appropriate. It can be controlled to a positive convex amount. Therefore, the curvature of the ABS surface of the slider can be controlled with high accuracy, the processing yield of the slider can be improved, and the variation in the flying height can be controlled. Further, the occurrence of the stiction phenomenon can be suppressed, and the CSS durability can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a wafer cutting process.

FIG. 2 is a perspective view showing a depth polishing process of a head element block.

FIG. 3 is a perspective view showing a process of aligning a head element block on a substrate.

FIG. 4 is a front view showing a sheet resist transfer process.

FIG. 5 is a front view showing the exposure process of the sheet resist.

FIG. 6 is a front view showing a developing process of the sheet resist.

FIG. 7 is a perspective view showing a powder beam etching process.

FIG. 8 is a perspective view showing a head element block cutting step.

FIG. 9 is a perspective view of a completed magnetic head device.

FIG. 10 is a characteristic diagram showing the relationship between the surface roughness and the block shape change amount.

FIG. 11 is a characteristic diagram showing the relationship between the average particle size of fine particles and the maximum processing depth / surface roughness.

FIG. 12 is a characteristic diagram showing the relationship between nozzle pressure and maximum processing depth / surface roughness.

FIG. 13 is a characteristic diagram showing the relationship between block strain and grain size.

FIG. 14 is a characteristic diagram showing the relationship between injection pressure and block distortion.

FIG. 15 is a characteristic diagram showing a relationship between block distortion and surface roughness.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer 2 Block for cutting 3 Head element block 4 Block processing jig 5 Substrate 6 Sheet resist 9 Nozzle of fine particle jetting processing device

Claims (2)

[Claims] 1. A method of manufacturing a magnetic head device in which a thin film magnetic head element is formed on one main surface of a slider so that a magnetic gap faces a surface facing a magnetic recording medium, and a plurality of thin film magnetic head elements are formed on a wafer. The thin film magnetic head element is cut into strips, and the back surface of the cut head element block opposite to the medium contact surface is subjected to powder beam etching, and then the medium contact surface of the head element block is cut. A method for manufacturing a magnetic head device, which comprises forming a predetermined shape by powder beam etching. 2. A method of manufacturing a magnetic head device in which a thin film magnetic head element is formed on one principal surface of a slider so that a magnetic gap faces a surface facing a magnetic recording medium, and a plurality of thin film magnetic head elements are formed on a wafer. The thin film magnetic head element is cut into strips, and the back surface of the cut head element block on the side opposite to the medium facing surface is subjected to mechanical grinding or mechanical polishing. A method of manufacturing a magnetic head device, wherein the medium contact surface is formed into a predetermined shape by powder beam etching.