JPS6177155A - Manufacturing device for thin film of laminate structure - Google Patents

Abstract

PURPOSE:To hold superior characteristics uniformly at respective parts by providing a mask which controls the transmission of a flying sputter material between a sputter source and a base body to be sputtered, and increasing opening width from the center axis side to outer peripheries. CONSTITUTION:Opening 14 and 15 which spread outward in the direction of a straight line (x) running in the centers of targets 10 and 11 are bored in the mask 9 at parts corresponding to the targets 10 and 11; while a base 6 is not in motion, rare earth metal from the target 10 at a different part of a base body 1 is sputtered and transition metal from the other target 11 is sputtered to the other half part. Then while the base 6 is rotated, the targets 10 and 11 are connected to a negative electrode to perform DC sputtering. A thin film 5 is deposited on and adhered to the base body 1 and a Tb layer 2 and an Fe layer 3 are laminated alternately and repeatedly. Consequently, the thin film of the structure of periodic lamination is manufactured, and this is applied for, for example, the manufacture of a photomagnetic recording medium, thereby manufacturing the medium having good characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is directed to a multilayer structure used for producing a magneto-optical recording medium applied to, for example, a rewritable magneto-optical disk.
This relates to I film production equipment.

[Summary of the invention]

In the present invention, a plurality of sputtering sources are arranged on the same circumference, and the substrate to be sputtered is rotated relative to the sputtering sources while sputtering is performed, thereby forming a laminated structure of ultra-thin thin film layers using sputtering materials from each sputtering source. This makes it possible to obtain a thin film based on the method.

[Conventional technology]

Writing with laser light, for example semiconductor laser light,
As a readable and rewritable magneto-optical disk, one made of an amorphous alloy of a rare earth metal and a transition metal has been proposed. As a method for obtaining such a magneto-optical disk, ie, a magneto-optical recording medium, there is a sputtering method. Sputtering in this case is done from one sputtering source. That is, the sputtering source, that is, the target, has a structure in which a rare earth metal pellet is placed on a transition metal target, and these metals are simultaneously sputtered onto the substrate. The magnetization curve (magnetization strength M - magnetic field strength H curve) of the magneto-optical recording medium obtained in this way is:
As shown in FIG. 3, the hysteresis characteristics are poor in squareness. Therefore, in this case, there is a problem that when an external magnetic field is applied to a recorded medium for some reason, the recording on the medium deteriorates and the S/N ratio decreases. Further, when using such a method, there is a problem in that it is difficult to obtain uniform sputtering over the entire area of the recording medium, and thus it is difficult to obtain a recording medium having uniform magnetic properties.

[Problem that the invention seeks to solve]

The present invention solves the above-mentioned drawbacks and provides an apparatus for producing a thin film having a laminated structure, which makes it possible to obtain a magneto-optical recording medium having uniformly excellent characteristics in each part.

[Means for solving problems]

In the present invention, a plurality of sputtering sources are arranged on the same circumference, a substrate to be sputtered is rotated about a central axis 0-0' of the circumference on which these sputtering sources are arranged, and the sputtering sources and the substrate to be sputtered are A mask is provided between the two substrates, each having apertures for transmitting the sputtering sputtering material from each sputtering source to the substrate to be sputtered, and regulating the respective sputtering areas. 0-0'
Select a shape that spreads from the side toward the outer circumference.

(Function) According to the apparatus of the present invention, sputtering materials from each sputtering source are alternately laminated on the substrate (1) where a plurality of sputtering sources are provided and sputtering is performed by rotating the substrate (1). By selecting the sputtering conditions, such as the rotational speed of the substrate (1), the width of the mask opening, and the applied voltage, an amorphous thin film with a superlattice structure is formed by periodically laminating ultrathin materials such as layers of each constituent element. can be created.

〔Example〕

FIG. 1 shows the line configuration of an example of the device of the present invention.
It has the configuration of a magnetron type sputtering device. In this case, a base (6) that rotates around a central axis 0-0' is provided in a bell jar (not shown), and a sputtering object, for example, a target thin film is deposited on the lower surface of the base (6), A substrate CI) made of a glass plate, a resin plate, etc. that constitutes a magneto-optical recording medium is arranged. and,
Two sputtering sources (7) and (8) are arranged facing the base (1) at equal intervals, that is, at an angular interval of 180°, about the axis 0-0'. These spatter m (
Between 7) and (8) and the base (6), that is, the base (1), there is a mask (9) for controlling the sputtering position of the metal sputtered from the sputtering sources (7) and (8), respectively. Deploy. The sputtering source (7) has a target α made of a plate of rare earth metal Tb, and the sputtering source (8) has a target (11) made of a plate of transition metal re. (12) and (13) each indicate a magnet.

For example, as shown in FIG. 2, the mask (9) has ginkgo leaves extending outward in the direction of a straight line Shape openings (14) and (15) are bored, and when the base (6) is stopped, the base (
The rare earth metal from one target αφ is sputtered onto mutually different parts of 1), for example, mainly one half, and the transition metal from the other target (11) is sputtered mainly onto the other half.

Then, while rotating the base (6), DC sputtering is performed with targets QO) and (11) on the negative electrode side.
(16) is a shutter, and this shutter (16) is placed between the sputtering source and the substrate to be sputtered as shown in the figure when the discharge is unstable at the start of sputtering, but when the discharge is stable be excluded.

Now, with this device, the base (6) is rotated at a rotation speed of 3 seconds per rotation for 6 minutes, that is, 1 rotation.
Sputtering was performed by rotating 20 times. In this case, a total of 1000 thin films (
5) was deposited. The thin film (5) thus formed has a structure in which Tb layers (2) and Fejii (3) are alternately and repeatedly stacked, as shown in FIG.

In addition, each layer (2
), (31 growth rate is, for example, 2 to 20 persons/second, in particular 5 to 10 persons/second, relative rotational speed of the substrate (1) and the sputtering source, to each sputtering source, that is, to each target. The selection is made by selecting the applied voltage, current conditions, etc. In other words, if the growth rate on the substrate is less than 2 people/second, it becomes difficult for the transition metal and the rare earth metal to form layers, and if the growth rate is less than 20 people/second. It is recognized that magnetic properties deteriorate when the

FIG. 5 shows the magnetization curve of the magneto-optical recording medium obtained by the above-mentioned apparatus of the present invention. In this case, an improvement in the squareness ratio can be seen compared to that of FIG. 3.

In the above example, each of the rare earth metals and the transition metal is composed of a single metal, but one or both of them may have a composition of two or more elements. For example, a TbGd alloy can be used as the rare earth metal, and a FeCo alloy can be used as the transition metal.

In this way, when the rare earth metal or (and) transition metal is composed of two or more metals, the target (10
1 or (and > (11)), respectively, or the target αω or (and) (11) is partially formed, in particular in the opening (1) of the mask (9).
4) Alternatively, (and) the area facing (15) may be selected so that the area ratio of each metal part corresponds to the composition ratio of each alloy to be finally obtained, or the target 00 Alternatively, as (11), a method may be adopted in which pellets of another metal are placed on a plate of one type of metal and the pellets are sputtered.

In addition, the sputtering source is related to rare earth metals and transition metals,
Although different sputtering sources are used in each case, a plurality of each of these can be provided.

〔Effect of the invention〕

According to the device of the present invention, although the required composition as a whole is obtained,
For example, each component material can be sequentially repeated as an extremely thin film layer for each element or each alloy to create a thin film with a periodically laminated structure, and as mentioned above, it can be used, for example, to create a magneto-optical recording medium. If it is accepted, it will be of great practical benefit because a medium with good characteristics can be produced.

[Brief explanation of the drawing]

Fig. 1 is a line configuration diagram of an example of the device of the present invention, Fig. 2 is a plan view of the main parts thereof, Fig. 3 is a magnetization curve diagram of a magneto-optical recording medium obtained by the conventional device, and Fig. 4 is a diagram of the present invention. FIG. 5 is an enlarged linear cross-sectional view of the magneto-optical recording medium obtained by the apparatus, and is a magnetization curve diagram thereof. (1) is a base, (6) is a base, and (7) and (8) are sputter sources. Same Matsukuma Hidemori 4Xi,,”',',. 2nd day 3rd day of Kaoru Tunkan's Sai 11. da＼, ji0 Figure 1 Half-view of the mask Figure 2 6 is good curve

Claims (1)

[Claims] A plurality of sputtering sources are arranged on the same circumference, and a substrate to be sputtered is rotated about a central axis of the circumference on which these sputtering sources are arranged, and a sputtering source is arranged between the sputtering source and the substrate to be sputtered. are each provided with a mask that has an opening for transmitting the flying sputtering material from each of the sputtering sources to the substrate to be sputtered and regulates each sputtering area, and each of the openings of the mask has an opening width that is at the center of the center of the sputtering target substrate. A device for producing a laminated thin film, characterized in that the shape is selected to expand from the shaft side toward the outer circumference.