JPH0520686A - Disc Carrier - Google Patents

Abstract

(57) [Summary] [Object] To provide a disk carrier for sputtering, which is used for manufacturing a thin film magnetic disk, capable of producing a thin film magnetic disk having uniform magnetic characteristics and excellent in durability. In a plate-shaped disk carrier 11 having a substantially circular hole in the central portion, a U-shaped groove 12 is provided in an inner peripheral surface 13 that supports the disk 2 upright, so that the disk 2 and the disk carrier 11 are separated from each other. The heat conduction is improved, the temperature distribution is uniform, and a thin film magnetic disk having uniform magnetic characteristics can be obtained. Further, since the partial concentration of thermal stress is suppressed, the disk carrier 11 is less likely to be deformed, and its durability is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for manufacturing a thin film magnetic disk used as a magnetic recording medium, specifically, for forming a material such as a magnetic material on both sides of the disk at the same time by using a sputtering method. Disc carrier.

[0002]

2. Description of the Related Art In manufacturing a thin film magnetic disk used for electronic equipment such as a disk drive, a method for forming a magnetic material for storing information on the disk is as follows.
Usually, the sputtering method is used. When performing the sputtering, the disk is inserted into a disk carrier and is erected, and a pair of vertical electrodes made of a magnetic material or the like is arranged outside both surfaces of the disk to simultaneously form the magnetic material or the like on both surfaces of the disk.

A conventional disk carrier used in this sputtering will be described with reference to the drawings.

FIG. 2 is a perspective view of a conventional disk carrier,
FIG. 3 is a detailed cross-sectional view taken along the line AA in FIG. 2, both showing a state in which a disc is mounted. As shown in FIGS. 2 and 3, the disc carrier 1 is plate-shaped, and a substantially circular hole 1a for inserting and standing up the disc 2 is provided in the center of the disc carrier 1. The shape of the hole 1a is such that the upper half is a substantially semicircular partial circle having a radius larger than the radius of the disk 2, and the lower half is a substantially semicircular partial circle having a radius slightly smaller than the radius of the disk 1. In order to facilitate the insertion of the disc 2, the center of the upper half partial circle is slightly shifted upward from the center of the lower half partial circle, and the circular opening of the disc carrier 1 has a circular opening. Taper 1b
Has been applied. Further, in order to support the disc 2 upright, a V-shaped groove 1c is provided on the inner peripheral surface of the lower half of the disc carrier 1 along the inner periphery thereof. In addition, V
In some cases, instead of the character-shaped groove 1c, a pin may be erected on the inner peripheral surface to support it.

[0005]

However, the sputtering using such a disk carrier has the following problems. First of all, the sputtering is performed while the disk and the disk carrier are heated. When the disk is supported by a conventional V-shaped groove or the like during the heating, the outer peripheral edge of the disk and the groove are Since heat conduction is carried out with a very small contact area with the side surface of the disk, heat is partially concentrated and the temperature distribution becomes non-uniform, resulting in thermal stress and deformation of the disk and disk carrier. Therefore, not only defects due to the deformation of the disk are likely to occur, but also the life of the disk carrier is shortened and the durability is deteriorated. Further, since the temperature distribution of the disk is non-uniform, the magnetic characteristics of the thin-film magnetic disk formed by sputtering become non-uniform, and the temperature of the disk easily fluctuates, so that a thin-film magnetic disk with high magnetic characteristics can be stably manufactured. Things were pretty difficult.

Secondly, the bias sputtering method has recently been used as a sputtering method for manufacturing a thin film magnetic disk having a high coercive force and excellent magnetic characteristics. When a bias voltage is applied, the inner peripheral edge of a conventional disk carrier is used. In the structure in which the taper is provided, the plate thickness becomes significantly thicker than the disk thickness as the distance from the inner peripheral surface increases, and the potential distribution becomes nonuniform. Therefore, there is a problem that not only the film thickness of the magnetic material and the like near the outer periphery of the disk becomes non-uniform but also the temperature distribution becomes non-uniform and a region having low magnetic characteristics is formed near the outer periphery.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a thin film magnetic disk having large and uniform magnetic characteristics and providing a disk carrier excellent in durability.

[0008]

In order to achieve this object, the present invention provides a plate-shaped disk carrier having a substantially circular hole at the center thereof, and the lower half of the hole of the disk carrier for standing and supporting the disk. The inner peripheral surface is provided with a U-shaped groove having a flat bottom surface along the inner peripheral surface and the width of the opening in the inner peripheral surface being larger than the width of the bottom surface. Further, if necessary, circular recesses are provided on both sides around the outside of the hole in the central portion, and the plate thickness of the recessed portion is made two to three times the thickness of the disc.

[0009]

With this structure, since the bottom surface of the U-shaped groove and the outer peripheral surface of the disk are in contact with each other, the contact area is widened, the heat conduction between the disk and the disk carrier is improved, and the generation of thermal stress is suppressed. In addition, the disk carrier is less likely to be deformed, and the non-uniform distribution of the temperature of the disk and the temperature fluctuation are suppressed, and an excellent thin film magnetic disk having uniform and large magnetic characteristics can be obtained.

Further, by providing the recess having a plate thickness of 2 to 3 times the thickness of the disk, it is possible to eliminate the non-uniform distribution of the electric potential in the vicinity of the outer circumference of the disk which has been conventionally generated when a bias voltage is applied. As a result, it is possible to manufacture a thin film magnetic disk having a uniform film thickness of a magnetic material or the like and excellent magnetic characteristics.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. However, since the overall structure of the disk carrier of this embodiment is similar to that of the conventional one shown in FIG. 2,
The description is omitted. FIG. 1 is a sectional view of a portion supporting a disc in the disc carrier of this embodiment, and its sectional position is the same as that in FIG. In FIG. 1, 11 is a disc carrier of the present invention, and 12 is a U provided along the inner periphery of an inner peripheral surface 13 of a hole for supporting the disc 2.
The bottom surface 14 of the groove 12 is flat like the outer peripheral surface of the disk 2, and the width of the bottom surface 14 is slightly larger than the thickness of the disk 2. In addition, the groove 12 in the inner peripheral surface 13
The width of the opening is larger than the width of the bottom surface 14, and the angle formed by the perpendicular line of the bottom surface 14 and the straight line connecting the peripheral edge of the bottom surface 14 and the peripheral edge of the opening portion of the groove 12 is about 5 degrees. With the groove 12 having such a shape, the disk 2 and the disk carrier 11 are separated from each other on the outer peripheral surface of the disk 2 and the bottom surface 14 of the groove.
The surface contact is made by and the heat conduction between the two becomes good, and it is possible to suppress the occurrence of the non-uniform distribution of thermal stress and temperature, which are the causes of the conventional problems.

Next, the depression will be described. In FIG. 1, reference numeral 15 denotes a recess formed on the plate surface by cutting off a part of both sides around the outside of the inner peripheral surface 13 of the hole of the disk carrier 11.
The opening of the recess 15 includes a hole for inserting and supporting the disk 2, and has a circular shape whose center coincides with the center of a semicircle formed by the inner peripheral surface 13. The plate thickness 16 of the portion where the depression 15 is provided is about 2.5 times the thickness of the disk 2, and in consideration of the occurrence of thermal deformation and potential distribution, a desirable range is 2 to 3 times. This is because if the plate thickness 16 is thinner than twice the thickness of the disc 2, thermal deformation is likely to occur and the life of the disc carrier is shortened, while if it is thicker than 3 times, a non-uniform potential distribution is likely to occur. . It should be noted that the diameter of the opening of the dent 15 should be taken into consideration in consideration of the occurrence of thermal deformation and non-uniform distribution of electric potential, but it should be 5 rather than the diameter of the disk 2.
It should be about 10 mm large. When such a depression 15 is provided, the thickness difference between the thickness of the disk 2 and the thickness of the plate on which the depression 15 is provided becomes small, and a non-uniform distribution of the potential generated near the outer circumference of the disk 2 when a bias voltage for sputtering is applied. Hard to do. Therefore, the film thickness of the magnetic material and the like becomes uniform, and the temperature distribution becomes uniform, so that a thin film magnetic disk having uniform and large magnetic characteristics can be obtained.

[0013]

As described above, according to the present invention, in a plate-shaped disk carrier having a substantially circular hole in the center used for sputtering a thin film magnetic disk, the inner peripheral surface of the disk supporting portion has its inner peripheral surface. By providing the U-shaped groove along with, the contact area between the disk and the disk carrier is widened to improve the heat conduction, the generation of thermal stress is suppressed, and the disk and the disk carrier can be prevented from being deformed. The temperature distribution of the disk becomes uniform, and a thin film magnetic disk having uniform magnetic characteristics can be obtained. Further, since the deformation does not easily occur, the life of the disk carrier is extended and the durability is improved.

Further, by providing the recess having a plate thickness of 2 to 3 times the thickness of the disk, it is possible to eliminate the non-uniform distribution of the potential which has been generated in the vicinity of the outer circumference of the disk when a bias voltage is conventionally applied. It is possible to manufacture a thin film magnetic disk having a uniform film thickness of a magnetic material and the like and excellent magnetic properties.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a portion of a disc carrier that supports a disc according to an embodiment of the present invention.

FIG. 2 is a perspective view of a conventional disk carrier.

FIG. 3 is a sectional view of a portion of a conventional disc carrier that supports a disc.

[Explanation of symbols]

2 discs 11 disk carrier 12 U-shaped groove 13 Inner surface 14 Bottom 15 hollow 16 Thickness

Claims (2)

[Claims] 1. A plate-shaped disk carrier having a substantially circular hole in the center thereof. The bottom half of the hole of the disk carrier, which supports the disk upright, has a flat bottom surface along the inner circumference. A disk carrier provided with a U-shaped groove in which the width of the opening in the inner peripheral surface is larger than the width of the bottom surface. 2. The disk carrier according to claim 1, wherein circular recesses are provided on both sides around the outside of the hole in the central portion, and the plate thickness of the recessed portion is set to be 2 to 3 times the thickness of the disk.