JPH0797684A - Thin film forming device - Google Patents

Abstract

PURPOSE:To prevent the contamination of a window and enable continuous observation with the device for evaporating the material in a vessel and depositing the material on a base by arranging a long-sized transparent film in the window for observing the inside of the device. CONSTITUTION:A magnetic recording medium is produced by evaporating the material put in the. vessel and depositing the material on the base. The transparent film 14 wound like a roll is housed in a case 13 having shielding walls 20a, 20b on the inner side of the window 12 disposed at the vacuum vessel 1 of the device. The device is so constituted that the transparent film 14 is drawn out of a feed side roll 15 and is taken up on a take-up side roll 16. The device is provided with a tension applying means for tensing the transparent film 14 in a longitudinal direction. As a result, the transmittability of light is improved and a sufficient visual field and light quantity are obtd. The distinct observation of the condition in the vacuum vessel 1 from the window 12 at the time of a thin film forming operation is thus possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus used for manufacturing a magnetic recording medium, for example.

[0002]

BACKGROUND OF THE INVENTION Magnetic recording media such as magnetic tapes are of a coating type in which a magnetic coating in which a magnetic powder or a binder is dispersed in a solvent is coated on a film which is a non-magnetic support.
There is a metal thin film type in which magnetic metal particles are deposited on a film without using a binder.

Among these, the metal thin film type magnetic recording medium is said to be particularly suitable for high density recording since the magnetic layer does not contain a binder and therefore has a high packing density of the magnetic material. Here, FIG. 5 shows a schematic configuration of a thin film forming apparatus used for manufacturing a magnetic recording medium. In FIG. 5, 21 is a vacuum container, 22 is a turbo pump, 23 is a rotary pump, 24 is a supply side roll of a support 26, and 25 is a support 2.
6 roll on the winding side, 27 is a cooling can, 28 is a crucible,
Reference numeral 29 is an electron gun, 30 is a shield plate, and 31 is an oxygen gas introduction tube.

Reference numeral 32 is a window for observing the inside of the vacuum container 21, 33 is a lid for opening and closing in the direction of the arrow, and 34 is an opening / closing lever for the lid 33 attached to the rotating shaft of the lid 33. In the thin film forming apparatus configured as described above, the vacuum pump 21 and the rotary pump 23 are operated to operate the vacuum container 21.
After making the inside a predetermined vacuum degree, the electron gun 29
By irradiating the magnetic material in the inside with an electron beam to heat and evaporate the magnetic material, and to evaporate the evaporated magnetic material on the support 26 sent from the supply-side roll 24 to the winding-side roll 25, a metal thin film is formed. It is formed.

By the way, it is necessary to observe the internal state of the apparatus when forming a thin film, and it is particularly important to observe the electron beam irradiation condition. That is, in the thin film forming work, the apparatus is adjusted in advance so that the electron beam hits the position of the crucible 28. However, as the work progresses, the electron beam is influenced by the magnetic field due to the magnetic particles scattered and accumulated around the electron beam. The beam is deflected, which may cause deviation from the initial setting condition, and the electron beam may be irradiated to a point different from the position of the crucible 28. Therefore, at the start of work, it is necessary to confirm that the crucible is reliably irradiated.

However, even if the lid 33 is provided, the lid 33 must be opened during the work, and the magnetic particles scattered around as the work progresses gradually adheres to the window 32. The window 32 becomes opaque, which hinders observation. In view of such problems, windows shown in FIGS. 6 and 7 have been proposed as windows provided in the thin film forming apparatus. 6 is a sectional view of the window portion of the thin film forming apparatus, and FIG. 7 is a front view of the window portion of the thin film forming apparatus.

In FIGS. 6 and 7, 35 is a window, 36 is a case, 37 is a glass plate, 38 is a disk with slits,
As shown in FIG. 7, slits 38a to 38c are formed at 120 ° intervals. Reference numeral 39 is a shaft connected to a driving means (not shown), and the glass plate 37 and the disk 38 with slits are configured to rotate at high speed around the shaft 39.

Reference numeral 40 is a shielding wall, and an opening 40a is provided in a portion corresponding to the window 35. In the thin film forming apparatus having such a window, the disk 38 with slits
By rotating at a high speed, the inside can be observed by the afterimage effect, and since the disk 38 with a slit is rotating at a high speed, the magnetic particles rarely pass through the slit and reach the window 35, It has a feature that it is difficult for the window 35 to be contaminated.

However, this slit-type window has a disadvantage that a sufficient field of view cannot be obtained because the size of the window is about the radius of the normal size in principle.
Since the amount of light is also insufficient, there is a problem that the internal state cannot be clearly observed, especially at the initial stage when the operation of the apparatus is started.

[0010]

DISCLOSURE OF THE INVENTION It is an object of the present invention to obtain a sufficient field of view and a sufficient amount of light so that the inside of the apparatus can be clearly observed, and it is difficult for the window to be contaminated due to the adhesion of evaporated magnetic particles, and it is possible to continuously operate for a long time. It is to provide a thin film forming apparatus capable of various observations and efficiently obtaining a high-quality magnetic recording medium having no defects.

The object of the present invention is a thin film forming apparatus for forming a thin film by evaporating a material placed in a container and depositing the material on a support, and a window for observing the inside of the apparatus is provided. The thin film forming apparatus is characterized in that a long transparent film is provided inside the window. That is, since a long transparent film is interposed between the window for internal observation and the container part that is the object to be observed, there is no problem in observing the inside of the device, however, the magnetic particles adhere to the transparent film. Therefore, if the transparent film becomes dirty after a long period of observation, the unused part can be pulled out and used whenever necessary, which allows continuous observation. Since it becomes possible and vapor deposition can always be performed under favorable conditions, a high-quality magnetic recording medium can be efficiently obtained.

The transparent film is preferably arranged such that at least one end is wound in a roll shape. With such a structure, the roll body formed by winding the transparent film is appropriately rotated. This makes it possible to pull out and use only the required length, and the handling becomes simple. In addition, it is preferable that a tension applying means for tensioning the transparent film in the length direction is provided, and with such a structure, sagging of the transparent film is prevented and the internal state can be more clearly observed. .

[0013]

1 to 4 show an embodiment of a thin film forming apparatus according to the present invention. FIG. 1 is a schematic view of the thin film forming apparatus, and FIG. 2 is a main part (window portion) of the thin film forming apparatus. 3 is a perspective view, FIG. 3 is a cross-sectional view of a main part (window portion) of the thin film forming apparatus, and FIG. 4 is a front view of a main part (window portion) of the thin film forming apparatus.

In each drawing, 1 is a vacuum container, 2 is a turbo pump, 3 is a rotary pump, 4 is a roll on the supply side of the support 6, a roll on the take-up side of the support 6, 7 is a cooling can, and 8
Is a crucible, 9 is an electron gun, 10 is a shielding plate, and 11 is an oxygen gas introducing pipe. Since these are well known in the art, detailed description thereof will be omitted. Reference numeral 12 is a window for observing the inside of the vacuum container 1, 13 is a case in which the transparent film 14 wound in a roll shape is stored, 15 is a film supply side roll, 16 is a film winding side roll,
A knob 17 is provided at the end of the rotary shaft of the film supply side roll 15.
a and 17b, and knobs 18a and 18b are attached to the end of the rotary shaft of the film winding side roll 16.
Incidentally, 19a and 19b are guide rollers.

That is, the transparent film 14 has the knob 18
By rotating a and 18b, as shown in FIG. 3, it is drawn out from the film supply side roll 15 and wound around the film winding side roll 16. Although not shown, a tension mechanism is provided, and this action keeps the transparent film 14 in a tensioned state, prevents the transparent film 14 from sagging, enhances light transmission, and makes the internal state clear. You will be able to observe.

Reference numerals 20a and 20b denote shield walls, and in particular, the shield walls 20a prevent magnetic particles from adhering to the surface of the transparent film 14 wound around the film supply side roll 15. In the thin film forming apparatus of the present invention configured as described above, the interior of the vacuum container 1 is evacuated to a predetermined vacuum degree by the turbo pump 2 and the rotary pump 3, and the electron gun 9 operates to remove the magnetic material in the crucible 8. When heating / evaporation is started, the inside of the vacuum container 1 can be clearly observed through the window 12, and if an error occurs in the electron beam irradiation position, this can be corrected immediately.

The transparent film 14 is used for a long time.
When the amount of magnetic particles attached to the sheet becomes large and the transparency becomes insufficient, the knobs 18a and 18b may be rotated to pull out the new transparent film 14 from the film supply side roll 15. It is possible to closely observe the internal state. Therefore, if the transparent film 14 has a sufficient length, continuous observation is possible, and the magnetic material vapor deposition work can be carried out under optimum conditions at all times, and a high-quality product can be efficiently obtained.

In this embodiment, the window has a circular shape, but various shapes can be used, and the shape is not limited at all.

[0019]

[Effects] According to the present invention, the inside of the apparatus can be clearly observed, and the contamination of the window due to the adhesion of evaporated magnetic particles is unlikely to occur, which enables continuous observation for a long time.
It is possible to efficiently obtain a high-quality magnetic recording medium having no defects.

[Brief description of drawings]

FIG. 1 is a schematic view of a thin film forming apparatus of the present invention.

FIG. 2 is a perspective view of a main part (window part) of the thin film forming apparatus of the invention.

FIG. 3 is a sectional view of a main part (window part) of the thin film forming apparatus of the invention.

FIG. 4 is a front view of a main part (window part) of the thin film forming apparatus of the invention.

FIG. 5 is a schematic view of a conventional thin film forming apparatus.

FIG. 6 is a cross-sectional view of a window portion in a conventional thin film forming apparatus.

FIG. 7 is a front view of a window portion in a conventional thin film forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum container 6 Support 7 Cooling can 8 Crucible 9 Electron gun 12 Window 13 Case 14 Transparent film 15 Film supply side roll 16 Film take-up side roll 19a, 19b Tensioning member 20a, 20b Shielding wall

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Shiga 2606 Akabane, Kai-cho, Haga-gun, Tochigi Prefecture Kao Co., Ltd.

Claims (3)

[Claims] 1. A thin film forming apparatus for forming a thin film by evaporating a material placed in a container and depositing the material on a support, wherein a window for observing the inside of the apparatus is provided, and the window is provided. A thin film forming apparatus, characterized in that a long transparent film is arranged inside the. 2. The thin film forming apparatus according to claim 1, wherein the transparent film is arranged such that at least one end is wound in a roll shape. 3. A tension applying means for tensioning the transparent film in the length direction is provided.
Alternatively, the thin film forming apparatus according to claim 2.