WO1991006397A1

WO1991006397A1 - Method of machining slider for magnetic head

Info

Publication number: WO1991006397A1
Application number: PCT/JP1990/001390
Authority: WO
Inventors: Masayuki Kuroda; Akio Mishima; Naoto Kojima
Original assignee: Sony Corporation
Priority date: 1989-10-30
Filing date: 1990-10-30
Publication date: 1991-05-16
Also published as: JP2940023B2; GB2245203B; JPH03149184A; GB2245203A; KR910008655A; GB9112704D0; KR100275055B1

Abstract

A method of machining a slider (16) for a magnetic head used in a hard disk or a floppy disk in which a groove (11) and a recess can be formed in an arbitrary shape by using a masking material (14) and jetting fine abrasive grains carried by a carrier gas against the slider (16), and the edges of the surface of the slider (16) are rounded when necessary by blending-machining with the fine abrasive grains.

Description

Specification

Title of invention Method for processing slider for magnetic head

Technical field

The present invention relates to a magnetic head river slider processing method, and more particularly to a method input for processing a surface of a magnetic head slider that is in contact with a recording medium into a predetermined shape or property. .. Background technology

On the surface of the slider that holds the magnetic head that writes or reads signals in contact with the magnetic recording medium such as a hard disk or a disc, contact the above recording medium. Grooves and protrusions are formed for the purpose of training, and in the past, such processing was performed by machining. And hard disk drive and floppy disk drive Along with the miniaturization, the slider is also miniaturized, and the machining accuracy is gradually required to be high.

Further, in the above-mentioned magnetic head slider, if the edge portion of the surface is not rounded, the hard disk or π ubi disk may be damaged. Therefore, conventionally, blending was performed as shown in Fig. 1. That is, the head slider (1) is held by the holding part (3) of the rotating disk, and is rotated about the rotating shaft (4). On the other hand, the urging force of the spring (5) presses the lapping sheet (7) from below through the pad (6) against the surface of the head slider (1). ..

When a slider for a magnetic head is manufactured by machining, it is necessary to precisely form a groove having an order depth in the depth direction from the machined surface, but this is extremely difficult. In addition, it is not possible to form a connecting portion across the groove, as when forming a negative pressure slider. It is extremely difficult to machine. For this reason, attempts have been made to use an ion-imaging method and a plasma etching method with photolithography as an alternative technique. With these methods, the above-mentioned difficulties will be cleared and high-precision machining will be performed. However, the processing speed is extremely slow, and moreover, it is necessary to evacuate before starting the work, and this has the disadvantage that it takes more time. In addition, since the equipment for such ion milling method and plasma etching method is expensive, it is not suitable for mass production.

In addition, the method in which the surface of the slider for the magnetic head is subjected to the lapping sheet (7) as shown in Fig. 1 is inferior in the dimensional accuracy of the pellet and the lapping sheet or It has the shortcomings of short tape life and unevenness. Furthermore, the maintenance is difficult, and if the sheet is adjusted by the pad pressure, there is a drawback that the variation becomes large ₍ and it is very difficult to obtain a blended curved surface.

The present invention has been made in view of the above problems, and is a method for processing a surface of a slider for a magnetic head with high precision and efficiency to give a predetermined shape or property. The purpose is to provide

A first invention is a method of processing a surface of a magnetic head slider, which is in contact with a recording medium, to have a predetermined shape or property, in which a solid-gas two-phase flow of loose abrasive grains and a gas is injected by an injection nozzle. The spray is applied to the surface of the slider.

In a second aspect of the invention, the average particle size of the free particles is as follows.

A third aspect of the present invention is the injection of the loose abrasive grains to provide the slider. Which has been subjected to a blending process that rounds the edges of the

<'Yes.

In the fourth invention, a solid-gas two-phase flow of loose abrasive grains and gas is jetted by a jet nozzle having a horizontally long rectangular cross section.

A fifth aspect of the present invention is that the nozzle nozzle has a rectangular cross section that is narrowed on both sides and rounded.

According to the first aspect of the invention, the loose abrasive grains are carried by the gas and jetted onto the work piece, and the exposed portion of the slider is exposed by the loose abrasive grains. As a result, grooves, recesses, protrusions, etc. of arbitrary shapes are formed, or the surface texture of the ejected portion can be brought into a predetermined state.

In particular, in the second aspect of the present invention, free abrasive grains having an average grain size of 10 m or less are jetted together with gas onto the surface of the slider for magnetic heads with high precision machining. Become.

Further, according to the third invention in which the blending is performed by spraying loose abrasive grains, the blending is performed together with the groove machining or the surface machining.

Also, by making the nozzle nozzle have a rectangular cross section as in the fourth invention, or by squeezing both sides to make it round as in the fifth invention, the machining speed distribution in the long side direction of the port Can be made uniform, and by performing machining while moving the workpiece in such a direction in the direction orthogonal to the long side of the injection port, the slider for the magnetic head can be made highly efficient. Can be processed into.

Brief description of the drawings

FIG. 1 is a vertical cross-sectional view of a main part showing a conventional blending process, FIG. 2 is an external perspective view of a substrate forming a slider according to the first embodiment of the present invention, and FIG. 3 is the same vertical cross-section. Fig. 4 is a schematic perspective view showing the processing of this substrate, Fig. 5 is a plan view of the machined slider, Fig. 6 is a sectional view taken along line V-V in Fig. 5, Fig. 7 is an enlarged sectional view of the rail portion, and Fig. 8 is a plan view of another slider. Fig. 9 and Fig. 9 are \ i ones in Fig. 8! ! Line sectional view, Fig. 10 is an enlarged sectional view of the rail part, Fig. 11 is a plan view of the H-type negative pressure slider, and Figs. 12 and 13 are plan views of a slide with a notch. Fig. 14 is a plan view of a slider with slanted grooves, Fig. 15 is a front view of the same, Fig. 16 is a plan view of a slider in which the edge portion of the groove is curved, and Figs. The same front view, Fig. 18 is a plan view of a slider with varying groove depth, Fig. 19 is a sectional view taken along the line Χ \ 1 to Χ Ι in Fig. 18, and Fig. 20 is the lateral machining speed of the nozzle. Fig. 21 is a graph showing the machining depth distribution by this nozzle, and Fig. 22 is a graph showing the machining speed distribution of the nozzle with narrowed edges on both sides of the nozzle. Fig. 23 is a graph of the same pressure distribution, Fig. 24 is an external perspective view of a flying head that has been added by the method according to the second embodiment, and Fig. 25 is a mask. Fig. 26 is an external perspective view of the flying head, Fig. 26 is a vertical cross-sectional view of the main part showing the blending process, Fig. 27 is a plan view of my cross rider, and Fig. 28 is XX VI! ~ XXW line sectional view, Figure 29 is a perspective view of the outside of the micro rider. BEST MODE FOR CARRYING OUT THE INVENTION

The magnetic head for the hard disk is formed on the part that is known as a slider. It is intended to stabilize the floating characteristics of the slider, and grooves, recesses and protrusions of any shape are formed on the surface of the slider. In the first embodiment, a special mask material is used. By doing so, grooves, recesses, and protrusions with arbitrary shapes are formed.

Is a of Surai da shown in FIGS. 2 and 3 material (10), high hardness Serra mix including the Aruchi' click _{_{(M 2 0 3 · T i}} C) is suitable. In this processing method, these high hardness ceramics are processed at high speed and with high precision. Allows processing in degrees. Of course, it is also possible to process ordinary slider materials such as titanium dioxide.

In this processing method, as shown in Fig. 4, high hardness abrasive grains such as SiC, IC, CBN, and diamond powder with an average grain size of 10 / m or less were dried. It is carried by a carrier (gas pressure of 1 to 10ks Z cnf) and jetted onto the base material (10) of the slider. At this time, only the portion to be processed is exposed on the slider (10) in advance by using the mask material (14). Abrasive grains on the exposed surface strike at a high speed, that is, at an ultra-high speed of l O OmZ s ec or more, and the metabolite of the base material (10) is rapidly abraded. The speed and surface roughness of the machined surface are controlled by the grain size of the abrasive grains and the dynamic pressure of the carrier gas. The processing speed increases regardless of whether the abrasive grain size or the gas dynamic pressure increases. On the other hand, the surface property is improved as the particle size becomes smaller and the dynamic pressure decreases. Therefore, by using this phenomenon, the abrasive grain size is first increased, roughing is performed at a high gas pressure, and then the finishing process is performed at a low gas pressure by using abrasive grains with a small grain size. A processed surface having a good surface property can be obtained.

A specific manufacturing process will be described. As shown in FIG. 2, the groove (11) is pre-machined on the base material (10) and the rails (12) on both sides are left. In this case, the stepped portion between the groove (11) and the rail (12) is made an inclined surface (13) if necessary. Then, a mask (14) is formed on the rail (12) to expose only the portion to be micromachined. In this state, the nozzle (15) is used to perform the spraying process as shown in FIG. At this time, the workpiece (10) is made to scan in a predetermined direction. After finishing the fine processing, the slider is obtained by dividing the substrate (10) at predetermined positions.

FIGS. 5 to 7 show a slider (16) for a magnetic head processed by such a method, and this slider (16) is Rails (12) are provided on both sides of the surface, and the shoulders of each rail (12) have a TPC (Tr ansver se Pr es re contour) groove

(17) is formed. The groove (17) is a groove for equalizing the flying height of the slider (16) on the inner peripheral side and the outer peripheral side of the recording medium. 6 and 7 show a mask (14) for forming these grooves (17).

Figures 8 to 10 show another example of the head slider (16). This head slider (16) is attached to the TPC groove (17) on both shoulders of the rails (12) on both sides. ) Is provided. That is, as shown in Figs. 8 and 9, on the rail (12), masks (14) are left on both sides of the rail (12), and the machining shown in Fig. 4 is performed. Therefore, a slider (16) having TPC grooves (17) on both shoulders can be obtained. By thus forming the TPC grooves (17) on both shoulders, it is possible to further reduce the difference in the flying height between the inner circumference side and the outer circumference side of the recording medium.

The slider (16) shown in FIG. 11 forms a connecting part (18) having a surface continuous with the rail (12) so as to cross the groove (11) formed on the rails (l Ra ¹ !) On both sides. Such a connecting part

By forming (18), the H-type negative pressure slider (16) is formed. The slider (16) shown in Fig. 12 is a modification of the slider shown in Fig. 11 and has a notch (19) formed on the air inflow side. In the slider shown in Fig. 13, the position of the connecting part (18) is located slightly downstream, and notches (19) are formed on the inflow side and the outflow side of the atmosphere, respectively.

The slider (16) shown in Fig. 14 and Fig. 15 has a trapezoidal shape for the middle atmospheric groove (11) formed between the rails (12) on both sides. It has a vertically elongated shape so that the width gradually increases from the side toward the outflow end. Figures 16 and 17 show atmospheric ditch (11) is further deformed, and the shape on both sides of the groove (11) that widens from the inflow end to the outflow end is curved.

Regarding the shape of the atmospheric groove (11) formed between the rails (12), it is possible to make the width constant and change the depth. That is, as shown in FIGS. 18 and 19, the groove (11) is made shallow on the inflow side and gradually changed so that it becomes deeper on the outflow end side. Such processing is obtained by changing the moving rate of the base material (10) with respect to the nozzle (15) shown in Fig. 4 to change the processing rate by the abrasive grains.

As described above, the method of processing the slider (16) according to the present embodiment is such that the fine abrasive grains are conveyed by the dry carrier gas and sprayed onto the base material (10) that constitutes the slider. Therefore, the mask (14) is used to expose only the part to be processed, and the mask (14) is used to form grooves, recesses, and protrusions of any shape. In such a method, the processing speed and the surface property of the processed surface can be controlled by the particle size of loose abrasive grains and the dynamic pressure of carrier gas. By controlling the grain size of the abrasive grains and the operation of the carrier gas by π —, it is possible to perform roughing and finishing, and thereby obtain a machined surface with good surface properties at high speed. It will be possible.

Moreover, according to such a processing method, it is possible to obtain a negative pressure slider (see FIGS. 11 to 13) and a slider (16) having a TPC groove (17), which are difficult to perform by conventional machining. .. Also, by using the mask material (14), it is possible to form grooves, recesses, and protrusions of any shape. <These external shapes can be formed in any shape, and an optimally designed slider is used. You will be able to actually process and mold the da. Also mask material

By using (14), it becomes possible to perform processing with higher accuracy compared to conventional machining. Moreover, the processing speed is improved compared to the ion milling method. In addition, preparation steps such as evacuation are required before starting processing. In comparison with the ion milling method, the time required for all processing is significantly shortened, and mass productivity is excellent. Moreover, the equipment is relatively simple to install, and the price as a mass-produced machine can be lower than that of an embedded machine.

Next, the injection nozzle (15) suitable for such processing will be described. As shown in Fig. 4, when performing abrasive grain processing while moving the base material (10) relative to the nozzle (15), the abrasive is uniformly applied in the width direction of the nozzle (15). It is desirable that the particles be sprayed. High-hardness fine abrasive grains (having an average grain size of 10 m or less) are conveyed by high-pressure carrier gas and sprayed onto the workpiece, which is called Bauta'beam etching.

No ,. U-beam etching is very similar to sandblasting, but the abrasive grain size used in sandblasting is 100 m or more, whereas that in powder-beam etching is 10 m or less. The controllability of processing also differs significantly. That is, in sandblasting, the abrasive grain flow and the carrier gas flow are essentially independent of each other, and the abrasive grain cannot follow the carrier gas flow. In grinding, the abrasive grains follow the flow of the carrier gas fairly well. Therefore, as shown in Fig. 20, by optimizing the tip shape of the nozzle (15) and controlling the pressure velocity distribution at the nozzle tip of the carrier gas, the machining speed is maximized. The distribution of processing depth can be made uniform.

In the nozzle shown in Fig. 20, the disfiguring shape of its nozzle (22) is a perfect rectangle. From the experimental results, the pressure distribution of the carrier gas and the processing distribution when the abrasive particles are actually conveyed and processed are uniform as shown in the figure. Figure 21 shows the distribution of machining depth when the surface of the slider (16) is machined using such a nozzle (15). The machining speed graph of Fig. 20 and the machining depth distribution map of Fig. 21, As is clear from the above, a slight local increase in both pressure distribution and working depth distribution was observed at the edges of the edges of the nozzle (15) nozzle (22). This is due to the viscous resistance between the nozzle and the wall of the nozzle (22), and it is presumed that the gas is trying to flow through the wall and the flow rate of the carrier gas increases at the edge. It In order to improve the non-uniformity of the distribution at both ends, as shown in Fig. 22, the shape of the edge of the nozzle (23) is narrowed. With such a shape, as shown in Fig. 23, the pressure distribution with respect to the position in the long side direction of the injection port (23) becomes almost uniform, and the optimum nozzle (15) can be obtained. It was

In this way, the shape of the opening (22) at the tip of the nozzle (15) is made rectangular, or by narrowing with both edges as shown in Fig. 22, the nozzle (15) is stopped. When processed in this state, a uniform processing depth distribution can be obtained. Therefore, by using such a nozzle (15) and moving the workpiece (10) relative to the nozzle (15) as shown in Fig. 4, it becomes possible to perform surface machining. The surface roughness, parallelism, uniformity and waviness of the machined surface have been greatly improved.

Next, a method of processing the slider of the second embodiment will be described. In this method, the edge of the edge of the slider (16) is finished by abrasive graining, and the edge is rounded to form a curved surface. Is. Fig. 24 shows a slider for magnetic head (16), which has a sliding surface consisting of rails (12) on both sides, and both ends of the rail (12) are inclined. The faces are (26) and (27). Here, the inclination angle of one inclined surface (26) is about 1 °, and the inclination angle of the other inclined surface is about 20 °. A head (28) is attached to the slider (16) so that winding can be performed through the winding groove (29). And The lead wire (30) is pulled out from the head tip (27). Then, in such a slider (16), the edge portions on both sides of the rail (12) are processed to form a blend processing surface (31).

When performing blending, as shown in Fig. 25,

From the surface of (12) to the surfaces of inclined surfaces (26) and (27), a resist mask (14) with a rubber hardness of about 60 ° is formed, which is a photosensitive polyurethane resin. In this case, it is desirable that the size of the mask (14) is the same as or slightly smaller than the surface of the rail (12). Here, the material of the slider (16) is made of difficult-to-machine material, but ordinary ceramic or ferrite material may be used.

After the mask (14) is formed, a solid-gas two-phase flow containing fine loose abrasive grains is jetted perpendicularly to the resist mask (14) or at an arbitrary angle, as shown in FIG. Figure 26 shows the jetting direction perpendicular to the surface of the mask (14). The nozzle (15) has a rectangular spigot (22) on the tip side, and the mouth width is about 0.05 to 1 mm. The length of the nozzle (22) of the nozzle (15) can be set to the optimum length depending on the size of the slider (16), and here the maximum is about 200 mm.

A loose abrasive grain supply pipe is connected to the nozzle (15), and loose abrasive grains made of SiC with a grain size of about 1 um are passed through this supply pipe at a high pressure of, for example, 2 to lOkgZ crf (16). The edges of the rails (12) are blended in this way to form a blended surface (31) composed of curved surfaces. By such a blending process, the groove (11) between the rails (12) can be simultaneously machined. Rails that make up the sliding surface

The step between the surface of (12) and the groove (11) can be processed in a short time up to about 1 to 100 «πι, and in the case of AlTiC material, the grain size of S i C is about 1 jum. , It is possible to obtain a surface roughness of about 0. Ol ^ m. Wear. Moreover, such fine processing can be performed in a short time. In other words, when finely processing the head slider (16), the shape accuracy of the blade processing and groove processing can be finished in the jum order. Next, the slider (16) processed by the modified method will be described with reference to FIGS. 27 to 29. This slider (16) relates to a slider with a low flying height, and the slider size is about 2 mm in width and length in outline dimensions, and the thickness is 0. It has a value of about 5 mm, and has very small and lightweight dimensions. In addition, the rail (12) of this slider has the shape of a wing, as shown in Fig. 27, and one side is curved. The small stepped groove (34) formed on the side of the rail (12) by making it curved is shallower than the central atmospheric groove (11) and forms a groove that controls the fluid boundary layer region. I am configuring.

In this way, the above-described blending can be performed even for the microfabrication of the microslider which is levitated by about 0. from the hard disk. That is, the edge portion of the rail (12) is blended to form a blended curved surface (31).

The method of blending is the same as above, but with the center groove

When processing (11) in advance, if the surface property is not so required, the surface other than the groove (11) should be resist-processed in advance and the grain size of, for example, 5 mm or more should be used. Spray processing with grains and then rail

It is possible to simultaneously perform blending processing of the wedge portion of (12) and processing of the shallow groove (34). In this case, the surface of the rail (12) will be pre-coated with a wing-shaped mask (14). In this case, the depth of the central groove (11) is about 50 Atm, and the groove (34) at the edge of the rail (12) is finished to 1 zm to several / s. Also, the surface roughness of the blending and grooving can be finished to about O. O lxm. The slider (16) described above is applicable to composite type and monolithic type heads, but it can also be applied to thin film type sliders. It can also be applied to magneto-optical heads and other pickup heads. That is, the range of application of this processing method is not limited to the above, but can be applied to other wide ranges.

As described above, the method of processing the slider according to the present embodiment is, for example, applying a photosensitive mask (14) of a photosensitive resin having the same shape as or slightly smaller than that of the rail, and approximately 1 m from the work surface perpendicularly or from an arbitrary angle By spraying fine abrasive grains with the same grain size at high pressure, blending, grooving, and hole machining are performed simultaneously. Therefore, it is possible to perform a surface finish that is not possible with conventional techniques and to shorten the processing time.

Claims

The scope of the claims

1. In a method of processing a magnetic head slider, which is in contact with a recording medium, into a predetermined shape or property, a solid-gas two-phase flow of loose abrasive grains and gas is sprayed by a spray nozzle. A method for processing a slider for a magnetic head, characterized in that the slider is sprayed onto the surface of the slider.

2. The method for processing a slider for a magnetic head according to claim 1, wherein the average particle diameter of the loose abrasive particles is 10 or less.

3. The slider for the magnetic head according to claim 1, wherein a blending process of rounding the edge of the surface of the slider is performed by the shot of the loose abrasive grains. Processing method.

4. The magnetic head according to claim 1, characterized in that a solid-gas two-phase flow of free abrasive grains and gas is injected by an injection nozzle having a horizontally long rectangular cross section. For processing slides for automobiles.

5. The method of processing a magnetic head slider according to claim 4, wherein the nozzle nozzle has a rectangular cross section which is narrowed from both sides and rounded.