JP2745086B2 - Method and apparatus for manufacturing magnetic disk - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mass-producing a magnetic disk used as a magnetic recording medium in an external storage device of a computer system.

[0002]

2. Description of the Related Art FIG. 8 is a sectional view showing a method of manufacturing a thin-film magnetic disk in the order of steps. Reference numeral 1 denotes a donut-shaped substrate made of a non-magnetic material such as aluminum, on which a NiP plating base layer 2 formed on the substrate is formed in a step (1).
A polishing tape is pressed against the surface of the rotating non-magnetic substrate to form fine texture grooves 3 in the circumferential direction.

In the step (2), a Cr layer 4 for improving adhesion is formed on the texture groove 3, and a magnetic film 5 made of a Co alloy or the like is formed thereon in the step (3). You. As shown in step (4), a carbon film 6 is formed as a protective film on the magnetic film 5, and finally a Fomblin lubricant 7 is applied. The Cr layer 4, Co alloy magnetic film 5, and carbon film 6 are formed by a technique such as sputtering.

The texture grooves 3 formed in the step (1)
This is for giving magnetic anisotropy to the magnetic film 5 for improving magnetic recording / reproducing characteristics. Further, since the carbon film 6 also becomes uneven along the texture grooves 3, the magnetic head is less likely to be attracted to the magnetic disk surface, and the friction between the magnetic head and the magnetic disk surface is reduced.

[0005]

As described above, in the conventional method, a doughnut-shaped non-magnetic disk is prepared in advance, and a wrapping tape is pressed against the rotating non-magnetic disk surface to obtain a texture in the circumferential direction. The magnetic disk is manufactured by forming the magnetic film 5 after forming the groove.

However, the texture processing in the step (1) must be performed one disk at a time.
(2) In forming the chromium film, the cobalt alloy magnetic film, and the carbon film in (3) and (4), the carrier 9 is held while a plurality of substrates 8 are held in a substrate holder 7 as shown in FIG. FIG.
Then, the film is passed on the front of the Cr target t1, the Co alloy target t2, and the carbon target t3 as shown in FIG. Finally, a lubricant 7 is applied to each disk.

However, in order to perform the operations of steps (1) to (4) in FIG. 8 in the state of a donut-shaped disk as described above,
In the texturing process, each disk must be mounted on a spindle mechanism and rotated, and in the sputtering process, each disk must be held or removed from the substrate holder 7. When forming a magnetic film by plating,
Many disks must be skewered and immersed in the plating solution.

[0008] As described above, the discs must be detached and attached one by one in each step, and special holding means must be used for transportation in the sputtering step and transportation between each step. Poor performance and not suitable for mass production. Such a problem becomes conspicuous when manufacturing a small-sized magnetic disk such as a 2.5-inch or 1.8-inch disk which has been widely used in recent years.

The technical problem of the present invention is to pay attention to such a problem, and to perform processing in each step in advance in the state of one sheet-like substrate, and finally to make it possible to separate the magnetic disk into a circular shape. To enable mass production of

[0010]

FIG. 1 is a flowchart for explaining the basic principle of a method for manufacturing a magnetic disk according to the present invention. According to the first aspect of the present invention, as shown in FIG. 1, a non-magnetic sheet-like substrate is used, and before it is cut into a circle, the non-magnetic sheet-like substrate is brought into surface contact with a non-magnetic sheet-like substrate via a wrapping tape in step (2). After performing texture processing at a plurality of locations by a rotating rotating disk, and also forming a magnetic film in step (3), in step (4), each of the textured areas is cut into a circular shape to form a plurality of magnetic disks. How to

According to a second aspect of the present invention, after a plurality of center holes of the magnetic disk are previously formed in the non-magnetic sheet substrate, each of the center holes is formed in the non-magnetic sheet substrate before being cut into a circular shape. A method of performing a texturing process with a rotating disk that rotates in surface contact with a wrapping tape based on a wrapping tape, and also forms a magnetic film, and then cuts each of the textured regions into a circular shape to form a plurality of magnetic disks. It is.

As shown in FIG. 4, a plurality of wrapping tapes 19 for performing texture processing are supported on support frames 21a and 21b on both sides of a non-magnetic sheet-like substrate 10, as shown in FIG. Turntable 13a,
13b so as to be rotatable, and wrapping tape 19
Manufacturing of a magnetic disk in which the rotating disks 13a and 13b are arranged so as to face the non-magnetic sheet substrate 10 so that the rotating disks 13a and 13b are in surface contact with the non-magnetic sheet substrate 10 via Device.

[0013]

According to the present invention, in the state of one sheet,
Perform processing such as texture processing and magnetic film formation,
Finally, since the disk is cut into a plurality of disks, operations such as texture processing and film formation of a magnetic film can be performed simultaneously in a single sheet state. Therefore, the work in each process becomes easy, and the attachment and detachment of the sheet-like substrate in each process, the movement during each process, the transportation between each process, etc.
It can be performed in a single sheet state. In this way, since each operation, attachment / detachment, transportation, and the like are performed all at once, and finally cut into a plurality of discs, it is suitable for mass production, and is extremely effective particularly when manufacturing small magnetic disks.

According to a second aspect of the present invention, a plurality of center holes of a magnetic disk are previously formed in a non-magnetic sheet-like substrate, and a texture process is performed on the basis of each of the center holes before cutting into a circular shape. Despite the fact that the non-magnetic substrate is in the form of a sheet, the texture processing can be performed accurately on the area to be the magnetic disk, and the texture groove is oriented so that it faces the rotation direction of the completed magnetic disk. It can be formed well.

According to a third aspect of the present invention, there is provided a non-magnetic sheet-like substrate.
On both sides of 10, a plurality of rotating disks 13a, 13b holding a wrapping tape are rotatably supported on supporting frames 21a, 21b, and each rotating disk 13a, 13b is mounted on a non-magnetic sheet-like substrate. Since the configuration is such that the rotating plates 13a and 13b on both sides are pressed against the sheet-shaped substrate 10 and rotated, texture processing can be performed on a large number of places on both sides of the sheet-shaped substrate 10 at the same time. And texture processing can be performed efficiently.

[0016]

EXAMPLES Next, how the method of manufacturing a magnetic disk according to the present invention is actually embodied will be described with reference to examples.
FIG. 2 is a side view showing the main steps from completion of a non-magnetic sheet-like substrate to completion of a magnetic disk. In step (2), a texture process is performed on the non-magnetic sheet-like substrate 10 prepared in step (1). Note that NiP plating may be performed before the texture processing.

The texture processing is a process of making a fine scratch in the circumferential direction at a position where a disk is to be formed by using an apparatus as shown in FIG. 4, and 11 is an area where a fine scratch is made in the circumferential direction. is there. When this texture processing is completed, step (3)
In FIG. 8, sputtering is performed on the Cr layer 4, the Co alloy magnetic film 5, the carbon film 6, and the like in FIG. Further, a lubricant is applied as needed. Each of the above processes is performed by
After the process is performed on a sheet-like substrate,
In (4), it is cut into a donut-shaped disk D. This disk D
Is a magnetic disk.

Prior to the texture processing in the step (2), a center hole 12 in each magnetic disk D is opened in the sheet-like substrate 10, and the next texture processing or the like is positioned with reference to the center hole 12. You can also do it.

FIG. 3 is a flowchart showing the method of the embodiment in the order of steps. The sheet-like substrate in the step (1)
A glass plate or an aluminum plate having a thickness of about 1 to 2 mm is used. Alternatively, a mirror-finished aluminum plate is used after both surfaces of the aluminum plate are previously finished by polishing or the like, and then NiP plating is performed in step (2). Thereafter, in step (3), a texture process is performed on both sides of the sheet-like substrate at a plurality of locations.

Next, in step (4), the Cr layer 4 in FIG.
After the sputtering of the Co alloy magnetic film 5 and the carbon film 6, etc., polishing is performed in step (5) using a wrapping tape. Then, in step (6), the sheet-like substrate is immersed in a lubricant solution to apply the lubricant.
Heating is performed in (7) to evaporate the solvent of the lubricant, and finally cut into donut-shaped disks.

FIG. 4 is a front view showing a state in which texture processing is simultaneously performed on the sheet-like substrate. Reference numeral 10 denotes a non-magnetic sheet-like substrate, which is previously subjected to NiP plating or the like as necessary. The sheet-like substrate 10 is sandwiched between a number of pairs of rotating disks 13a and 13b from both sides.
The texture processing is performed by rotating a and 13b for about 2 seconds, for example. In the drawing, five pairs of the rotating disks 13a and 13b are arranged vertically, but a plurality of pairs are arranged also in the horizontal direction and arranged in a matrix, so that the texture of many magnetic disks can be simultaneously formed. Processing can be performed.

FIG. 5A shows one of the rotary disks 13a in FIG.
It is an expanded sectional view which shows a side in detail. The turntable 13a is shown in FIG.
(c) It has a cup shape as shown, and a circular rubber disc 14 is press-fitted therein. The rubber disk 14 is an elastic disk made of, for example, sponge, solid rubber, or the like, has almost the same outer diameter as the completed magnetic disk, and has a flat surface so that the wrapping tape can be adsorbed. The back side is, for example, a radial rib as shown in FIG.
A large number of holes 16 are formed between the ribs 15 to 15 and penetrate to the surface side.

A cylindrical rotary shaft 17 integral with the cup-shaped rotary plate 13a
Is connected to the vacuum pump P via the coupling C and the pipe 18.
Connected to the rib 15 side of the rubber disc 14
When the wrapping tape 19 is applied to the surface side of the rubber disc 14 in a state where the wrapping tape 19 is pressed into the cup-shaped portion of a, the wrapping tape 19 is caused by the differential pressure between the negative pressure in the through hole 16 and the atmospheric pressure.
Adsorbed and held on the surface of 14.

In this manner, when the rubber disc 14 on which the wrapping tape 19 is adsorbed is rotated by the rotating discs 13a and 13b while being pressed against the non-magnetic sheet-like substrate 10 from both sides, the rotation direction of the wrapping tape 19 is changed. Texture processing is performed by making numerous scratches on the surface.

As shown in FIG. 4, a large number of rotating disks 13a,.
are provided, and a gear 20 is fixed to each cylindrical rotating shaft 17 so that they can rotate in conjunction with each other. The cylindrical rotating shaft 17 of each of the rotating disks 13a and 13b is
And the gear 20 are inserted and supported by bearings 22 of support frames 21a and 21b on both sides of the sheet-like substrate 10.

As shown in FIG. 4, the gears 20 of the rotary discs 13a, 13b are meshed with each other and can be interlocked, so that one of the gears 20 is used as an output gear of the motors M1, M2.
By engaging with G1 and G2, all the rotating discs 13a ..., 13
b ... can be rotated all at once. Note that the coupling C has a seal structure such that the negative pressure does not leak even when the gear 20 rotates with respect to the fixed pipe 18.

By the way, the wrapping tape 19 is a rubber disc.
It is better to repress the sheet-like substrate 10 via 14 with a predetermined pressure. For this purpose, a coil spring 24 is sandwiched between the thrust bearing 23 on the turntable 13a side and the bearing 22 of the support frame, and a coil spring 26 is provided between the thrust bearing 25 on the gear 20 side and the bearing 22 of the support frame. It is sandwiched.

Therefore, the support frame 21a shown in FIG.
When the left and right support frames 21a and 21b are simultaneously moved toward the sheet-like substrate 10 while the 21b is supported by the guide shaft 27, the respective rotating plates 13a and 13b are resiliently pressed against the sheet-like substrate 10 by the coil springs 24. You. At this time, the support frames 21a, 21b move toward the sheet-shaped substrate 10 until the tips of the stopper pins 28a, 28b fixed to the left and right support frames 21a, 21b abut against the sheet-shaped substrate 10, so that the sheet-shaped The spring pressure applied to the substrate 10 from the left and right becomes constant.

In the illustrated example, each of the rotating disks 13a,.
The gears 20 are used to link..., But a timing belt, a chain, or the like may be used.

By the way, in order to perform a process involving a rotational motion such as a texture process, as shown in FIGS. 2 and 3, a center hole 12 of a donut-shaped disk is previously formed in the sheet-shaped substrate 10. It is preferable to open the hole and to perform the processing based on the center hole thereafter. For this purpose, in the embodiment of FIG. 6, a cylindrical positioning shaft 30 rotatable in the center hole 12 of the sheet-like substrate 10 is press-fitted and fixed in the cylindrical rotary shaft 17 on one of the rotary disks 13a.

In the center of the left and right rubber discs 14, 14,
There are center holes 31a and 31b slightly smaller in inner diameter than the center hole 12 of the sheet-like substrate 10, and the center holes 31
Since the positioning shaft 30 penetrates a and 31b,
There is no air leakage between the two. An axial hole 32 and a radial hole 33 communicate between the through hole 16 on the back surface of the rubber disk 14 and the cylindrical hole 29 of the cylindrical rotary shaft 17.

On the other hand, a positioning shaft 34 having an outer diameter capable of just fitting into the cylindrical portion of the positioning shaft 30 is press-fitted and fixed in the cylindrical hole 29 on the left rotating disk 13b side. When 13a and 13b are brought close to the sheet-like substrate 10,
The positioning shaft 30 of the right turntable 13a fits into the center hole 12 of the sheet-like substrate 10, and the positioning shaft 34 of the left turntable 13b
By fitting into the cylindrical hole of the right positioning shaft 30, the left and right turntables 13a and 13b rotate around the center hole 12 of the sheet-like substrate 10 to enable texture processing.

The portion of the left positioning shaft 34 which is in contact with the center hole 31b of the left rubber disc 14 is slightly larger in diameter than the center hole 31b.
Is open.

After texture processing is performed on both surfaces of the sheet-like substrate 10 in this manner, the left and right rotating disks 13a and 13b are retracted from the sheet-like substrate 10, and the sheet-like substrate 10 is transferred by the carrier 9 in FIG. Therefore, the target t1 in FIG.
Pass between t1, between t2 and t2, between t3 and t3, and
A Cr film, a Co alloy magnetic film, and a C film are sequentially laminated on both surfaces of the substrate. When forming a film by plating, the sheet-like substrate 10 is immersed in a plating solution.

Next, polishing, application of a lubricant,
Heating and the like are also performed in the state of a sheet-like substrate, and the area on which the above-mentioned texture processing has been performed is finally cut into a circle to complete a large number of magnetic disks at the same time. There are various methods for cutting into a circle. For example, using laser light, cutting out by electric discharge machining, cutting with high pressure jet water flow, punching out by press working, cutting off by lathe processing, etching the cut part with a chemical solution, dissolving away the disc area with a solvent, etc. Although there is a method, a method that does not impair the magnetic characteristics of the magnetic film formed earlier is suitable.

The separation by lathe processing can be performed by using a cutting-off tool or a male tool cutting tool and rotating each tool on a rotary multi-axis lathe at the same position as the outer diameter of the magnetic disk.

In order to etch the cut portion with a chemical, FIG.
Before performing the sputtering in the step (3), the sputtering is performed with a ring-shaped mask provided at the outer peripheral position of the magnetic disk, and then the mask is removed. When the sheet-like substrate is immersed in an etching solution such as hydrochloric acid or the like, the mask is removed and only the region where the aluminum substrate is exposed is cut into a ring shape, so that the substrate is simultaneously cut into a plurality of disks.

The above embodiment is based on the premise that the non-magnetic substrate is made of aluminum. However, when the substrate is made of synthetic resin, the entire area other than the disk area can be removed by corrosion with a solvent. . In this case, before the sputtering in the step (3) of FIG. 2, the area other than the disk, that is, the area other than the textured area 11 is covered with the masks 35 and 36 as shown in FIG. Then, the sputtering in the step (3) in FIG. 2 is performed.

With the masks 35 and 36 removed after the sputtering, the sheet-like substrate 10 is immersed in a solvent 37 as shown in FIG. Is left, a plurality of donut-shaped magnetic disks remain.

Before dissolving with an organic solvent, as shown in FIG. 7C, when the textured area 11 is covered with a shielding disk 38 having the same shape as the magnetic disk and is melted with the solvent, spattering occurs. It is possible to reliably prevent the region where the cleaning has been performed from being damaged by the organic solvent. As a synthetic resin constituting the sheet-like substrate 10, PMMA, polyethylene terephthalate, or the like is used. In this case, benzene or phenol is suitable as the organic solvent.

[0041]

As described above, according to the present invention, in a state where the non-magnetic substrate is in the form of a single sheet, after processing such as texturing and forming a magnetic film, the non-magnetic substrate is formed into a plurality of disks. For separation, work such as texture processing and magnetic film formation can be performed all at once in the form of one sheet.
Moreover, in addition to the work in each step, the attachment and detachment of the substrate in each step, the movement during each step, the transportation between each step, and the like are simplified, which is suitable for mass production of magnetic disks.

Further, a plurality of center holes of a magnetic disk are previously formed in a non-magnetic sheet-like substrate, and a texture process or the like is performed with reference to each center hole. Area and direction are accurate.

As described in claim 3, on both sides of the non-magnetic sheet substrate 10, the supporting frames 21a and 21b
Wrapping tape 19 for performing texture processing
In a state in which a plurality of pairs of rotating disks 13a and 13b holding the pair of rotating disks 13a and 13b are rotatably supported, the pairs of rotating disks 13a and 13b are pressed against both surfaces of the sheet-like substrate 10 so as to make surface contact, and the sheet is rotated. Texture processing can be simultaneously performed on a large number of places on both sides of the substrate 10, and the texture processing can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a basic principle of a method of manufacturing a magnetic disk according to the present invention.

FIG. 2 is a side view showing main steps from completion of a non-magnetic sheet-like substrate to completion of a magnetic disk.

FIG. 3 is a flowchart showing a method of the embodiment in the order of steps.

FIG. 4 is a front view of the texture device showing a state in which texture processing is being simultaneously performed on a sheet-like substrate.

FIG. 5 is a view showing details of one of the rotary disks 13a in FIG. 4;

FIG. 6 is a center sectional view of an apparatus for performing a texture process based on a center hole of a magnetic disk previously opened in a sheet-like substrate.

FIG. 7 is a diagram exemplifying a method of cutting a nonmagnetic sheet-like substrate into a circle with an organic solvent when the substrate is made of a synthetic resin.

FIG. 8 is a sectional view illustrating a method of manufacturing the thin-film magnetic disk in the order of steps.

FIG. 9 is a perspective view showing a conventional substrate holder.

FIG. 10 is a plan view showing a conventional sputtering method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Non-magnetic substrate 2 NiP plating base layer 3 Texture groove 4 Cr layer 5 Co alloy magnetic film 6 Carbon film 7 Substrate holder 8 Circular substrate 9 Carrier 10 Non-magnetic sheet substrate 11 Textured area 12 Sheet Center holes 13a, 13b Rotating disc 14a Rubber disc 15 Radial rib 16 Rubber disc through hole 17 Cylindrical rotating shaft 18 Piping C Coupling P Vacuum pump 19 Wrapping tape 20 Gear 21a, 21b Support frame 22 Bearing 23 , 25 Thrust bearing 24,26 Coil spring M1, M2 Rotating disk drive motor G1, G2 Motor output gear 27 Guide shaft 28a, 28b Stopper pin 29 Cylindrical hole 30,34 Positioning shaft 31a, 31b Rubber disk center hole 32 Positioning Shaft axial hole 33 Positioning shaft radial hole 35,36 Mask 37 Solvent 38 Disc-shaped shield

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Akiha 5400-2 Omori, Higashi-nemoto, Higashi-ne, Higashine-shi, Yamagata (No address) Inside Yamagata Fujitsu Co., Ltd. (72) Inventor Kiyoshi Yamaguchi, Nakahara-ku, Kawasaki-shi, Kanagawa 1015 Odanaka Fujitsu Co., Ltd. (72) Inventor Masahiro Takagi 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Co., Ltd. (No address) Inside Yamagata Fujitsu Co., Ltd. (72) Inventor Fumio Fukasawa 1015, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Co., Ltd. (72) Inventor Hiroyuki Nakamura 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (56) JP-A-64-55739 (JP, A) JP-A-62-232726 (JP, A) JP-A-62-102965 (JP, A) JP-A-61-104431 (JP, A) JP-A-62 JP-A-165728 (JP, A) JP-A-3-113721 (JP, A) JP-A-62-63058 (JP, A)

Claims (3)

(57) [Claims] 1. Using a non-magnetic sheet substrate, lapping the non-magnetic sheet substrate before cutting it into a circular shape
The rotating disk surface contact rotates through the tape, subjected to texturing process at a plurality of locations, and after the magnetic film is also formed, the plurality of magnetic disks each realm that textured said separately in a circular A method of manufacturing a magnetic disk. 2. After a plurality of center holes of a magnetic disk are previously formed in a non-magnetic sheet substrate , each of the above-mentioned center holes is formed in the non-magnetic sheet substrate before cutting into a circular shape. Surface contact via wrapping tape based on
Texture processing is performed by the rotating rotating disk .
And claim 1 magnetic film even after forming, characterized in that a plurality of magnetic disks each realm that textured said separately in a circular
The manufacturing method of the magnetic disk described in the above. 3. On both sides of the non-magnetic sheet-like substrate (10), the supporting frames (21a, 21b) are textured.
The wrapping tape (19) a plurality of rotating disk that holds (13a, 13b) a pair of rotatably supported for performing, via the wrapping tape (19) each rotating disk (13
a, 13b) are in surface contact with the non-magnetic sheet-like substrate (10)
A rotating disk (13a, 13b) is disposed so as to face a non-magnetic sheet-like substrate (10).