JPH03272019A - Magnetic recording medium and production thereof - Google Patents

Abstract

PURPOSE:To prevent the generation of attraction of a head in a CSS zone and to allow the low floating of the head in a data zone by forming a protective film for protecting a magnetic film by sputtering, then subjecting the protective film to a texture treatment to decrease the surface roughness of the data zone smaller than the surface roughness of the CSS zone. CONSTITUTION:A substrate 1 is subjected to the 1st texture treatment to work the surface roughness over the entire part of the substrate to the extent of averting the attraction of the head and the magnetic film on which the data is written is formed by sputtering. The protective film to protect the magnetic film is formed by sputtering. The protective film is then subjected to the 2nd texture treatment to make the surface roughness of the data zone 2 smaller than the surface roughness of the CSS zone 3. The attraction of the head does not arise in the CSS zone 3 in this way and the low floating of the head in the data zone 2 is allowed.

Description

[Detailed Description of the Invention] [Summary] Regarding a method for manufacturing a magnetic recording medium having a data zone where data is written and a C3S zone where the head comes into contact, the head does not attract in the CSS zone and the head does not stick in the data zone. The manufacturing method for magnetic recording media that can achieve low flying height is ``1'', and the surface roughness of the entire substrate is adjusted to a level that prevents the head from attracting it.
1 first texture processing step (step 11)
, a step of forming a magnetic film on which data is written by sputtering (step 12), a finishing step of forming a protective film to protect the magnetic film by sputtering (step 13), and adjusting the surface roughness of the data zone to the CSS zone. and a second texture processing step (step 14) to make the texture smaller.

[Industrial Field of Application] The present invention relates to a method of manufacturing a magnetic recording medium in which a data zone in which data is written and a CSS zone in contact with a head are defined.

In recent years, due to the increase in magnetic recording density, the flying height of the head tends to be extremely low. Therefore, it is necessary to suppress the surface roughness of magnetic recording media.

[Prior Art] Next, a conventional example will be explained using the drawings. FIG. 11 is a flow diagram showing an outline of a conventional method for manufacturing a magnetic recording medium.

In the figure, first, an aluminum alloy or glass substrate is formed (step 1).

Next, a tape polishing process called texturing process is performed on the substrate (step 2). This process is performed to smooth the surface roughness on the substrate.

Next, a magnetic film is formed on the substrate by sputtering (step 3).

Subsequently, a carbon protective film is formed on the magnetic film by sputtering (step 4).

In addition, during sputtering in these two steps,
In order to control the magnetic properties and film quality, the substrate is heated (300° C. or less) in advance.

Head burnishing is then performed to remove minute protrusions using a magnetic head whose flying height is set lower than the flying height of the magnetic head set at the actual gap (step 5).

Finally, a lubricant is applied to reduce friction (step 6).

[Problems to be solved by the invention] In the above-mentioned conventional manufacturing method, in the texture processing in step 2, the entire surface of the substrate is processed under the same conditions, so the data zone where data is written and the head are The surface roughness is the same as that of the contacting CSS-/-.

Therefore, in an attempt to lower the flying height of the head, the surface i
(2) When the size is made small, there is a problem that the head attracts the head in the CSS zone.

On the other hand, if the surface roughness is increased in an attempt to prevent the head from being attracted, there is a problem in that it is difficult to lower the flying height of the head.

Furthermore, in the texture of step 2, it is possible to selectively change the surface roughness only in the data zone or the CSS zone, but the surface roughness will change during sputtering in the subsequent process. Since the rate of change is unstable, there is a problem in that it is difficult to predict the amount of change and process it.

The present invention has been made in view of the above problems, and its purpose is to provide a method for manufacturing a magnetic recording medium that does not cause head adhesion in the CSS zone and allows the head to fly at a low level in the data zone. be.

[Means for solving the problem] FIG. 1 is a diagram showing the principle of the present invention. In the figure, step 11 is a first texturing process in which the surface roughness of the entire substrate is processed to such an extent that the head does not attract it, and step 12 is a process in which a magnetic film on which data is written is formed by sputtering. Step 13 is a step of forming a protective film to protect the magnetic film by sputtering, and step 14 is a second texturing step to make the surface roughness of the data zone smaller than that of the CSS zone.

[Function] In the method for manufacturing the magnetic recording medium shown in FIG. 1, the surface roughness of the data zone becomes CSS in two seconds.
smaller than the zone. Therefore, adsorption of the head does not occur in the CSS zone, and it is possible to lower the flying height of the head in the data thin.

[Example] Next, an example of the present invention will be described using the drawings. Second
The figure is a schematic flow diagram explaining an example of the method for manufacturing a magnetic recording medium of the present invention, FIG. 3 is a plan configuration diagram of a polishing apparatus used in the second texture treatment shown in FIG. 3 is a partial cross-sectional configuration diagram, FIG. 5 is a diagram illustrating the surface roughness of the CSS zone of a magnetic recording medium manufactured by the manufacturing method shown in FIG. 2, and FIG. FIG. 7 is a diagram illustrating the surface roughness of the data zone of the manufactured magnetic recording medium, and FIG. 8 is a diagram illustrating the friction characteristics of the CSS zone of the magnetic recording medium manufactured by the manufacturing method shown in FIG. 2. 2 is a diagram explaining the friction characteristics of the data zone of the magnetic recording medium manufactured by the manufacturing method shown in FIG. 2, and FIG. 9 is a diagram explaining the CS of the magnetic recording medium manufactured by the manufacturing method shown in FIG. 2.
FIG. 10 is a diagram explaining the flying characteristics of the head in the S zone, and FIG. 10 is a diagram explaining the flying characteristics of the head in the data zone of the magnetic recording medium manufactured by the manufacturing method shown in FIG.

First, the manufacturing method of this embodiment will be explained using FIGS. 2 to 4.

First, a substrate 1 made of aluminum alloy or glass is molded (step 21).

Next, a first texture treatment (tape polishing treatment) is performed on the entire substrate 1 (step 22).

In this example, the tape used was 1 A$4,000.

Next, a magnetic film is formed on the substrate by sputtering (step 23).

Subsequently, a carbon protective film is formed on the magnetic film by sputtering (step 24).

Next, a second texture process is performed only on the data zone 2 on the substrate 1. (Step 25). In this embodiment, as shown in FIGS. 3 and 4, a rotatably provided circular pad 5 with a tape 6 attached to the bottom surface is used. Then, put the tape 6 of the bad 5 on the board 1.
to rotate the substrate 1. Then, the pad 5 polishes the data zone of the substrate 1 while rotating. still,
The tape 6 used is 1A1600.

Then, using a magnetic head whose flying height is set lower than the actually set flying height of the magnetic head, head vanishing is performed to remove minute protrusions (step 26).

Finally, a lubricant is applied to reduce friction (step 27).

Next, the surface characteristics of the magnetic recording medium manufactured by the above manufacturing method will be explained separately for data zone 2 and C3S/- zone 3.

First, the surface roughness on the substrate 1 will be explained using FIGS. 5 and 6. As you can see by comparing these two figures, the surface roughness of data zone 2 (center line average roughness: Ra
60 to 70A) is smaller than the surface roughness of CSS zone 3 (center line average roughness: Ra go to 90X).

Next, the frictional characteristics on the substrate 1 will be explained using FIGS. 7 and 8. In these two figures, (a) shows the friction coefficient when the substrate 1 is rotated at 1 rps, and (b) shows the coefficient of friction when rotating the substrate 1 at 1 rps.
After completion, the change in the friction coefficient is shown when the substrate 1 is rotated at 1100 rpm for 1 hour, and (c) shows the characteristics of the friction coefficient when the substrate 1 is then rotated under the same conditions as in (a). ing.

As can be seen by comparing these two figures, the friction coefficient of CSS zone 3 is smaller than that of data zone 2, indicating that the head is less likely to attract.

Next, the flying characteristics of the head over the substrate 1 will be explained using FIGS. 9 and 10. In this measurement, an acoustic element is installed on the head (head arm), and when the head is in contact with the substrate 1, the acoustic element outputs a voltage, and when the head floats above the substrate 1, the acoustic element outputs a noise level voltage. It is supposed to be done.

As can be seen from a comparison of these two figures, the flying characteristics in CSS zone 3 are not good, but in data zone 2, the head flies due to low synchronization.

Therefore, in the manufacturing method described above, adsorption of the head does not occur in the CSS zone 3, and it is possible to lower the flying height of the head in the data zone 2. Then, the data read/write characteristics become advantageous, and it becomes possible to increase the recording density.

Further, after sputtering, only the data zone was selectively textured (polished) again. By doing this, you can reliably obtain the desired surface texture,
Variations can be suppressed.

Note that the present invention is not limited to the above embodiments.

For example, in the above embodiments, the substrate 1 was described as being an aluminum alloy, but it goes without saying that a glass substrate may also be used.

[Effects of the Invention] As described above, according to the present invention, the first texture processing step (step 11) of processing the surface roughness of the entire substrate to such an extent that the head does not attract it, and the magnetic film on which data is written. a step (step 2) of forming a protective film for protecting the magnetic film by sputtering (step 13); and a second texture treatment to make the surface roughness of the data zone smaller than that of the CSS zone. (Step 14).

Therefore, it is possible to realize a method of manufacturing a magnetic recording medium in which head adhesion does not occur in the CSS zone and the head can be lowered in flying height in the data zone.

[Brief explanation of drawings]

Fig. 1 is a diagram of the principle of the present invention, Fig. 2 is a schematic flow diagram illustrating an example of the method for manufacturing a magnetic recording medium of the present invention, and Fig. 3 is used during the second texture processing shown in Fig. 2. FIG. 4 is a plan view of the polishing apparatus; FIG. 4 is a partial sectional view of FIG. 3; FIG. Figure 6 is a diagram explaining the surface roughness of the data zone of the magnetic recording medium manufactured by the manufacturing method shown in Figure 2, and Figure 7 is the CSS of the magnetic recording medium manufactured by the manufacturing method shown in Figure 2. Figure 8 is a diagram explaining the frictional characteristics of the data zone of the magnetic recording medium manufactured by the manufacturing method shown in Figure 2. Figure 9 is a diagram explaining the frictional characteristics of the data zone of the magnetic recording medium manufactured by the manufacturing method shown in Figure 2. FIG. 10 is a diagram illustrating the flying characteristics of the head in the CSS zone of the manufactured magnetic recording medium. FIG. 10 is a diagram explaining the flying characteristics of the head in the data zone of the magnetic recording medium manufactured by the manufacturing method shown in FIG. FIG. 11 is a flowchart showing an outline of a conventional method for manufacturing a magnetic recording medium. In FIGS. 1 to 10, 1 is a substrate, 2 is a data zone, 3 is a CSS zone, 5 is a pad, and 6 is a tape.

Claims (1)

[Claims] In a method of manufacturing a magnetic recording medium having a data zone in which data is written and a CSS zone in contact with a head, a first texture is provided in which the surface roughness of the entire substrate is processed to such an extent that the head does not attract it. a processing step (step 11), a step of forming a magnetic film in which data is written by sputtering (step 12), a step of forming a protective film to protect the magnetic film by sputtering (step 13), and a step of forming a data zone by sputtering. A method for manufacturing a magnetic recording medium, comprising a second texturing step (step 14) to make the surface roughness smaller than the CSS zone.