JPS59201229A - Manufacture of magnetic disk - Google Patents

Abstract

PURPOSE:To simplify the process of removing sticking matters and improve cleaning effect by blowing air to the surface of a substrate by using air blowing nozzles which move radially over the substrate at specific distance to the substrate surface. CONSTITUTION:While both-surface sputtering is carried out in a room A by rotating the substrate 4, film thickness is monitored, and the substrate is moved to a room B in the middle; and high-speed clean and dry air of room temperature is blown to the rotating substrate 4 while nozzles 6 and 7 are moved radially over the substrate 4. The nozzles 6 and 7 are arranged at 2-3 distance from the surface of the substrate 4 and held at the access part 12a of an access device 12 while the distance is maintained; and they are put in radial reciprocation at a long period >=5 times as long as the rotation period of the substrate 4 to blow away impurities on the film. Thus, the process is simplified to improve the cleaning effect.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a magnetic disk, and in particular to a method for forming a thin film on a substrate by sputtering. Regarding the method.

<Prior art and background> A magnetic disk, which is the recording medium of a magnetic recording device, is usually a mechanical structure in which a magnetic film of a predetermined thickness is coated on a base with a smooth, disk-shaped surface by painting, plating, sputtering, etc. It is formed by forming a recording layer, and in order to improve the recording density, it is necessary to form a thin film that is partially defect-free and homogeneous and has a uniform thickness.

Sputtering methods have been used to obtain magnetic disks for high density recording. However, when forming a film by sputtering, not all of the evaporated material becomes a film.

Rather than forming a film by strongly adhering to the substrate or a previously formed film, the film could not be formed by solidifying in space or by falling off from what was accidentally attached. If impurities are generated and these adhere to the surface of the film being formed during the Subhanota process, a film with a different density will be formed or will fall off later, resulting in defects in the film. Therefore, when forming a magnetic film by sputtering, a film of a predetermined thickness is not formed all at once, but cleaning is performed to remove these impurities during the process. A typical method is as follows: (1) The substrate on which the film has been formed is removed from the sputtering apparatus and scrubbed with an alkaline detergent.

■ Rinse with pure water.

■ Mount the board on a rotating device and press the pad against the surface while rotating to mechanically remove any deposits.

■ Rinse with pure water.

■ Degrease and clean with R solvent (repeat multiple times if necessary)
.

■ Dry.

A film of a predetermined thickness is usually formed in 3 to 5 steps while removing impurities during sputtering as a unit.

However, this method has disadvantages in that cleaning requires equipment that takes up a lot of space, drying time, and labor involved in moving the substrate between the equipment, which increases the working time.

<Purpose and Features> The purpose of the present invention is to improve the above-mentioned cleaning process, and after trying various methods, it has been found that the process is extremely efficient and has no superior cleaning effect. The aim is to provide an extremely simple method that is as good as any other.

A feature of the present invention is that in order to achieve the above object, the sputtered substrate is cleaned in the cleaning step after sputtering in the step of forming a thin film that will become a magnetic recording layer by sputtering a multimagnetic material onto the surface of the substrate. Sputtering is achieved by spraying clean and dry gas onto the substrate surface at high speed using a gas spraying nozzle that is movable in the radial direction of the substrate while maintaining a predetermined distance from the substrate surface while rotating. This is to avoid blowing away impurities that sometimes adhere to the thin film.

<Embodiment> FIG. 1 is a conceptual explanatory diagram of an embodiment of the present invention, showing a semi-automated film sputtering apparatus and a substrate mounted on an operating jig for sputtering.

In the figure, A is a sputtering chamber, and 1 and 2 are evaporation sections for evaporating sputtering sources, respectively, which are under a reduced pressure atmosphere.

B is the outside room, 3 is the main body of the operating jig, and 4 is the board.

3a, 3b, and 3c are grooved rollers for holding the outer periphery of the substrate 4 on the main body 3; The board 4 is configured to be rotated, and the main body 3 of the operating jig is configured to be placed on or attached to a conveyor 5 and moved between rooms A and B. And 6 and 7 are nozzles for spraying the body.

In this configuration, the substrate 4 attached to the main body is rotated and the film thickness is monitored while double-sided sputtering is performed in room A, and the film thickness is monitored (measuring by film formation rate x time or direct measuring means) and the substrate 4 is taken out to room B midway through. While rotating the nozzles 6 and 7 while moving in the radial direction of the substrate 4, impurities adhering to the film surface are blown off by blowing clean, dry, and temperature gas at high speed, and then the film is returned to room A and sputtered. The process of continuing film formation is repeated to form a sputtered film of a predetermined thickness.

The above is an overview of one embodiment of the present invention, and the conditions for spraying will be explained in more detail below.

FIG. 2 is an explanatory diagram of one embodiment of the present invention, and is a detailed explanatory diagram of the nozzle and gas surroundings.

The substrate 4 in the figure is mounted on and rotated by a rotary table 11 driven by a motor 10, but basically the first
The rotation state of the board is not different from the one shown in the figure.

The nozzles 6 and 7 are respectively disposed at positions 2 to 3 times away from the surface of the substrate 4, and the access section 12a of the access device 12 moves the nozzles in a radial direction similar to the magnetic head access mechanism while maintaining the distance. The impurities adhering to the film are almost completely blown away by moving the film back and forth in the radial direction at a slow period of at least 5 times the rotation period of the substrate 4 (usually several tens of times). I was able to do it.

To show more specific conditions, in the experiment, NL gas was adjusted to 5 to 10 atm, and sucked (q) from a pipe with an inner diameter of 8ψ to 2ψ at the nozzle.The amount of NZ gas consumed at this time was It was about 30β/min when converted to 1 atm, and 2 to 3 minutes was sufficient for cleaning a 10.5-inch substrate.

What is more, the blowing angle of the gas to the substrate surface is not perpendicular but 45
It was found that tilting the rotation downstream at an angle of about 75 degrees resulted in better removal and no fear of re-adhesion.

Moreover, the quality of the magnetic disk obtained by applying this process was actually superior to that obtained by the conventional method.

<Effects> As explained above, according to the present invention, deposits can be physically removed by blowing gas, and the step of removing deposits is easy because liquid detergent solution, pure water, organic solvent, etc. are not used as a medium. It has the characteristic effect of being able to simplify both equipment and man-hours, and improve product yield.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of an embodiment of the present invention. FIG. 2 is a detailed diagram of an embodiment of the present invention. In the figure, A indicates the sputtering chamber 3, which is an operating jig, and 4 indicates the substrates 6 and 7, which are used for gas spraying. Figure 1 1θth? figure

Claims (1)

[Claims] In the cleaning process after sputtering in the process of forming a thin film that will become a magnetic recording layer by sputtering a separable material onto the substrate surface, the sputtered substrate is rotated while maintaining a predetermined distance from the substrate surface. , and is characterized in that impurities attached to the thin film during spuntering are blown off by blowing clean and dry gas onto the surface of the substrate at high speed using a gas blowing nozzle that is movable in the radial direction of the substrate. A method for manufacturing magnetic disks.