JPH0486742A - Apparatus for manufacturing thermomagnetic recording medium - Google Patents

Abstract

PURPOSE:To form a multilayer film having several kinds of structures in a short time by providing a shutter rotatably held between a target and a substrate and having plural openings capable of opposing both in the peripheral direction and partitioning plates set at each opening and different from other in shielding position and shielding area. CONSTITUTION:The target 14 arranged opposite to the substrate 11 is formed by electrically connecting and joining a Co part 14a and a Pt part 14b into a circular form. As a rotary plate 12 rotates, a Co/Pt or Co/Pd synthetic lattice film is formed on the substrate 11. The part of the first shutter 21 corresponding to the substrate 11 and the target 14 is provided with the opening 24 through which sputtering is executed in the step of forming said lattice film on the substrate 11. On the other hand, the 4 parts of the second shutter 22 corresponding to the substrate 11 and the target 14 in the peripheral direction are provided with the openings 25 - 28, and the partitioning plates 31 - 34 are arranged for these openings 25 - 28, thus permitting the multilayer film having multiple structures to be formed only by manually rotating the shutter without opening the sputtering device.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for manufacturing a thermomagnetic recording medium suitable for forming a magnetic latent image.

BACKGROUND OF THE INVENTION Traditionally, magnetic printer drum materials have been used, for example, in thermomagnetic printers, where a magnetic latent image is formed on the magnetic printer drum and this is magnetically developed to obtain a visible image. (“Magnetography Printer” by Shunjin Imamura, edited by Makoto Ohno, CMCr Non-Impact Printing, Chapter 15 P, 159-P, 168.1986
reference).

FIG. 4 is a printing process diagram of a conventional thermomagnetic printer.

In the figure, a recording magnetic drum 1 rotates in the direction of arrow A. A Cry2 thin film, etc., which is a thermomagnetic recording medium for forming a magnetic latent image, is provided on the surface of the recording magnetic drum.

In the printing process, first, the demagnetizing means 2 magnetizes the thermomagnetic recording medium in a certain direction. Next, the magnetic recording means 3 forms a predetermined magnetic latent image, and the developing means 4 deposits toner on the magnetic latent image, thereby making the magnetic latent image visible.

Here, the toner adheres to the area where the lines of magnetic force due to the leakage magnetic field on the surface of the thermomagnetic recording medium intersect with the surface of the thermomagnetic recording medium,
As a result, the magnetic latent image becomes a visible image.

Thereafter, the transfer means 5 and the fixing means 6 transfer and fix the visible image onto the paper. Finally, the cleaning means 7 removes the residual toner on the thermomagnetic recording medium and ends the printing process.

By the way, methods for recording a magnetic latent image on the thermomagnetic recording medium include a method using a thermal head and a method of heating by laser beam irradiation. In addition, the magnetization direction of thermomagnetic recording media is mainly divided into two directions: along the recording medium surface (in-plane recording method) and perpendicular to the recording medium surface (perpendicular recording method), which require high resolution. In some cases, perpendicular recording is used. The magnetic recording medium of perpendicular recording paper is
Alloy film of rare earth elements and iron group elements, i.e. RE-7M
It is formed of an alloy film or a Co-Cr alloy film. RE-7M
Alloy films are often used in magneto-optical disks using a thermomagnetic recording method, and Co--Cr alloy films are often used in magnetic disks using a magnetic recording method.

Furthermore, thin films such as Co/Pt superlattice and Co/Pd superlattice can also be used as perpendicularly magnetized films to perform thermomagnetic recording.

However, Co--Cr alloy films have a high Curie point, making thermomagnetic recording difficult. Furthermore, since the RE-7M alloy film has a low residual magnetic flux density, the adhesion of toner is insufficient. In addition, in the case of a Co/Pt superlattice film or a Co/Pd superlattice film, the squareness ratio of the magnetic hysterinos curve is l in an extremely thin state where the total film thickness is several hundred nanometers, but when the total film thickness is If there are several thousand people, the squareness ratio will be less than 1, making it impossible to obtain the residual magnetic flux density necessary for thermomagnetic recording, and the coercive force will also be 500.
It is small, about 0e.

As described above, although thermomagnetic printers using perpendicular magnetization films for perpendicular recording have high recording stability in principle, can obtain high resolution, and operate with low power consumption, There was a problem in that there was no suitable material for the perpendicular magnetization film.

Therefore, a thermomagnetic recording medium is provided in which a perpendicular magnetization film is formed by alternately laminating artificial lattice films and thin films on a substrate.

FIG. 5 is a cross-sectional view of a conventional thermomagnetic recording medium with a multilayered structure.

In this case, the superlattice film is formed of a Co/Pt superlattice film in which Co layers and ptN layers are alternately laminated, or a Co/Pd superlattice film in which 00 layers and Pd layers are alternately laminated; This is a Pd thin film.

In the case of this thermomagnetic recording medium, the residual magnetic flux density is high, and it generates sufficient magnetic force required to attract toner, which is a magnetic substance, and also has a high coercive force (and a low cue temperature).

Fig. 6 does not show a conventional sputtering apparatus for thermomagnetic recording media, and Fig. 6(A) shows a sputtering apparatus! Front view, Figure 6 (B)
is a target layout diagram, and FIG. 6(C) is a Shishima ivy layout diagram.

In the figure, reference numeral 11 is a substrate placed on a rotary plate 12 and on which a multilayer film with a multilayer structure is formed by sputtering. The rotating plate 12 is connected to ground.

Reference numeral 14 denotes a target disposed opposite to the substrate 11, which includes a Co portion 14a and a Pt (or Pd) portion 14b.
has a semicircular shape, and the two are electrically contacted and joined to form a circular shape. Target 7) 14 includes:
A common sputtering power source 15 is connected to the Co portion 14a and the Pt (or Pd) portion 14b.

In the sputtering apparatus having the above configuration, as the rotary plate 12 rotates, the two parts 14a of the target 14,
The substrate 11 rotates on the substrate 14b, and the substrate 11 rotates on the substrate 14b.
A Co/Pt superlattice film or a Co/Pd superlattice film is formed thereon.

Subsequently, the sputtering apparatus is opened, and a thin film of PT or Pd is deposited on the Co/Pt superlattice film or the Co/Pd superlattice film.

Therefore, a circular shutter 16 is provided between the substrate 11 and the TARDEF 14. A circular opening 17 is formed in the portion of the shutter 16 facing the substrate 11 and the target eye 4, and in the step of forming a Co/Pt superlattice film or a Co/Pd superlattice film on the substrate 11, , the opening 17 is opened.

In addition, when forming a Pt or Pd thin film on the Co/Pt superlattice film or the Co/Pd superlattice film, the portion of the opening 17 facing the target CO is shielded by an unillustrated partition. .

Then, the formation of the Co/Pt superlattice film or the Co/Pd superlattice film and the formation of the pt or Pd thin film are repeated to form a multilayer film with a multilayer structure.

The gloss 16 can be manually rotated, and when performing a reverse svanta during preliminary treatment of the surface of the substrate 11, it is rotated 180 degrees to avoid staining the target grain 4.

(Problems to be Solved by the Invention) However, in the conventional thermomagnetic recording medium manufacturing apparatus described above, since a multilayer film with a multilayer structure is formed, the magnetic properties such as the cue point and residual magnetic flux density of the thermomagnetic recording medium are However, a sputtering device is required to manufacture it, which increases the size and complexity of the device. In addition, when forming a thin film of PT or Pd, it is necessary to open the -degree apparatus and shield half of the target, which complicates the manufacturing method and lengthens the manufacturing time. Furthermore, oxidation of the substrate occurs when the device is opened.

(Means for Solving the Problems) For this purpose, in the thermomagnetic recording medium manufacturing apparatus of the present invention, two parts made of different components are electrically contacted and joined together, and connected to a common sputtering power source. A connected target and a substrate disposed opposite the target and periodically moved are provided.

Between the target and the substrate is a rotatable support so that it can be rotated manually.

Evening is arranged. The shutter is provided with a plurality of openings at positions facing each other in the circumferential direction.

Each of the openings is provided with a partition plate having a different shielding position and a different shielding area.

(Function) According to the present invention, as described above, two parts made of different components are joined by electrically contacting each other, and a target connected to a common sputtering power supply is provided, and the target is opposed to the target. A substrate is disposed and the substrate is moved periodically.

The two components of the target are alternately laminated by sputtering to form an artificial lattice film, and the artificial lattice film and a thin film of one of the mouth components are further alternately laminated to form a multilayered film. .

In this case, when forming a superlattice film, it is necessary to sputter two components, and when forming a thin film, only one component is sputtered.

Therefore, when sputtering only one component, it is sufficient to shield the other component.

Therefore, a sputtering plate with a plurality of openings is rotatably arranged between the target and the substrate so that they face each other, and a partition plate is placed in each opening to provide shielding between each sputtering process. The position and shielding area are variable.

The component can be selected by rotating the shutter and changing the shielding position, and the thickness of the layer can be changed by changing the shielding area.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to a concave surface.

The first part shows a sputtering apparatus for implementing the thermomagnetic recording medium manufacturing apparatus of the present invention, FIG. 1(A) is a front view of the sputtering apparatus, and Part 1(B) is a plan view of a target. 2 is a plan view of the first shutter of the sputtering apparatus shown in FIG. 1, and FIG. 3 is a plan view of the second shutter of the sputtering apparatus shown in FIG.

In the figure, reference numeral 11 is a substrate disposed on a rotating Fi 12, on which a multilayer film with a multilayer structure is formed by sputtering. The rotating plate 12 is connected to ground.

14 is a target disposed opposite to the group Fi11, which includes a 00 portion 14a and a Pt (or Pd) portion 1.
4b has a semicircular shape, and they are electrically contacted and joined to form a circular shape. The target 14 includes a unitary Co portion 14a and a Pt (or Pd) portion.
A common sputtering power source 15 is connected to the portion 14b.

In the sputtering apparatus having the above configuration, as the rotating plate 12 rotates, the two portions 14a, 1 of the target eye 4
The substrate 11 rotates on the substrate 4b, and a Co/Pt superlattice film or a Co/Pd superlattice film is formed on the top two parts of the substrate 11.

A first shutter 21 and a second shutter 22 each having a circular shape and independently rotatably supported are disposed between the rotary plate 12 and the target shutter 4.

A circular opening 24 is formed in a portion of the first shutter 21 corresponding to the substrate 11 and the target 14, and is used in the step of forming a Co/Pt superlattice film or a Co/Pd superlattice film on the substrate 11. Sputtering is performed through the opening 24.

On the other hand, openings 25 to 28 are formed in the second shutter 22 at four locations in the circumferential direction corresponding to the substrate 11 and the target eyes 4. Then, as shown in FIG. 3, the openings 25 to 2
8 includes first to fourth partition plates 31 to 34 of various shapes.
will be erected. Each of the partition plates 31 to 34 has openings 25 to 2
8 and a hanging portion 35 extending downward through the openings 25 to 8.
It consists of a shielding part 36 that is locked to the edge of the opening 28 and that shields a predetermined portion of the openings 25 to 28.

The hanging portion 35 includes each portion 14a, 1 of the target 14.
Each component of 4b is sputtered in a separated state, and is formed to completely shield when one is shielded, and prevents alloying of both components.

Further, the shielding portion 36 has a shape shown by hatching in FIG. 3. That is, the shielding portion 36 of the first barrier Fi 31 has a thin strip shape, and both the Co portion 14a and the Pt (or Pd) portion 14b of the target 14 are opposed to the substrate 11.

Further, the shielding portion 36 of the second partition plate 32 has a rectangular shape that covers half of the opening 26, and has a rectangular shape that covers half of the opening 26.
It covers only the Co portion 14a.

The shielding part 36 of the third partition plate 33 has a rectangular shape that covers slightly less than half of the opening 27, and has a rectangular shape that covers a little less than half of the opening 27.
Pt (or P
d) Open the part facing the part 14b to face the substrate 11.

The shielding portion 36 of the fourth partition plate 34 is connected to the opening 28.
It has a rectangular shape that covers half of the target 7 and the Pt (or Pd) portion 14b of the eye 4.

In the sputtering apparatus having the above configuration, when forming an artificial lattice film, the second shutter 22 is rotated to a position W such that the opening 25 and the target eye 4 face each other, and the substrate 11 is rotated above this. When changing the ratio of each layer thickness, the third partition plate 33
Use different shielding areas, such as And Pt
When forming a thin film or a paffllll, the second shutter 22 is rotated so that the Co part 14a is hidden by the second partition plate 32, and sputtering is performed. Further, by using the fourth partition plate 34, it is possible to form a multi-layered film using a CO thin film.

As described above, according to the thermomagnetic recording medium manufacturing apparatus of the present invention, the second shutter 22 of the first and second shutters 21 and 22 is provided with a partition plate in advance, so that the sub-bar 7 and A multilayer film with a multilayer structure can be formed simply by manually rotating the second sensor 22 without opening the inside of the apparatus. In this case, a multilayer film with several types of structures is sequentially formed:
It can be formed in a short time without oxidation.

When the magnetic properties of the multilayer film thus formed were evaluated, it was found to be C under the conditions of Ar gas pressure of 50 mTorr, substrate rotation speed of 5 rpm, and target input power of 500 W.

The total film thickness is 15 when the layer thickness is 2 people and the PT or Pd layer thickness is 5 people.
In a multi-structure multilayer film consisting of an artificial lattice film with a thickness of 0 and a thin film of PT or Pd with a film thickness of 150, the residual magnetic flux density is 10.
00 Guss or more, the cue temperature is 200°C or less, and the coercive force is about 30,000e.

If a similar film is formed using a conventional method, similar magnetic properties can be obtained, but the manufacturing time will be several times to several tens of times longer.

Note that the present invention is not limited to the above embodiments,
Various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

For example, in the above embodiment, a Co/Pt or Co/Pd artificial lattice film and a pt or Pd thin film are used as the multi-structure multilayer film, and the stacking period and film thickness of the artificial lattice film are changed to pt or Pd.
d The film thickness of the thin film is fixed, but these thicknesses can be easily changed by changing the size and position of the partition plates 31 to 34, and can be easily changed when the film has a complex structure, such as a fractal multilayer film. can be easily formed.

(Effects of the Invention) As described above in detail, according to the present invention, the thermomagnetic recording medium is a Co/Pt or Co/Pd superlattice film which is a perpendicularly magnetized film with a low Curie point and high residual magnetic flux density. It is formed by a multilayer film in which thin films of PT and Pd are alternately laminated.

Therefore, a magnetic recording density for perpendicular recording can be obtained. For example, when this is used in a thermomagnetic printer, resolution can be increased and power consumption can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a sputtering apparatus for implementing the thermomagnetic recording medium manufacturing apparatus of the present invention, FIG. 1(A) is a front view of the sputtering apparatus, and FIG. 1(B) is a plan view of the target. 2 is a plan view of the first shutter of the sputtering apparatus shown in FIG.
Fig. 3 is a plan view of the second shutter of the sputtering device shown in Fig. 1, Fig. 4 is a printing process diagram of a conventional thermomagnetic printer, and Fig. 5 is a sectional view of a conventional thermomagnetic recording medium with a multilayer structure. , FIG. 6 is a diagram showing a conventional sputtering device for thermomagnetic recording media, FIG. 6(A) is a front view of the sputtering device, and FIG. 6(B)
) is a target arrangement diagram, and FIG. 6(C) is a shutter arrangement diagram. DESCRIPTION OF SYMBOLS 11... Substrate, 12... Rotating plate, 14... Target, 21... First shutter, 22... Second shutter,
31-34... Shikiri board, 36... Shielding part. Patent applicant: Oki Electric Industry Co., Ltd. Agent, Patent attorney Makoto Kawai (1 other person) Plan view of the first interface Figure 2 Spatter 1 [fs Figure 1 Y rainbow loincloth ivy diagram Figure 3 Procedures Teho Seisho (self-initiated) Specification December 27, 1990

Claims (1)

[Scope of Claims] (a) A target in which two parts made of different components are joined in electrical contact and connected to a common sputtering power source; (b) A target disposed opposite to the target. (c) a shutter that is rotatably supported between the target and the substrate and has a plurality of openings formed at positions where the two face each other in the circumferential direction; (d) An apparatus for manufacturing a thermomagnetic recording medium, comprising a partition plate disposed in each of the openings and having a different shielding position and a different shielding area.