JPH0797680A - Thin film forming equipment - Google Patents

Abstract

PURPOSE:To stably form a uniform metallic thin film having high quality by vibrating a crucible contg. a metal melt for vapor deposition and removing the oxide on the surface of the molten metal by flanges on the inside surface of the crucible at the time of forming the metallic thin film on the surface of a film-like base by a vacuum vapor deposition method. CONSTITUTION:While a polyethylene terephthalate film 21 is moved on the surface of a cooling can 1 in a vacuum vessel 6, the magnetic metal 5 in the crucible 7 is melted and evaporate by irradiation with an electron beam and the thin film consisting of the magnetic metal 5 is deposited by evaporation on the surface of the film 21. Suspended matter S of the metal oxide is formed on the surface of the molten magnetic metal 5 in the crucible 7 in such a case. The suspended matter is heated to a high temp. by irradiation with the electron beam and produces plashes by coming into contact with the magnetic metal of a relatively low temp., thereby damaging the magnetic film on the surface of the film 21. The flanges 8a, 8b are, therefore, mounted at the inside surface of the crucible 7 and the crucible 7 is tilted 3 to 45 deg. to filter away the suspended matter S of the oxide by the flanges 8a, 8b and, therefore, the splashes are not generated. The magnetic metallic film having the uniform film quality is thus formed on the film at a high yield.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium manufacturing apparatus.

[0002]

BACKGROUND OF THE INVENTION In a magnetic recording medium such as a magnetic tape, due to a demand for high density recording, a binder resin is not used as a magnetic layer provided on a non-magnetic support, instead of a coating type using a binder resin. It is well known that a metal thin film type that is not used has been proposed.

That is, there has been proposed a magnetic recording medium having a magnetic layer formed by a wet plating means such as electroless plating, or a dry plating means such as vacuum deposition, sputtering or ion plating. Since the magnetic recording medium of this type has a high packing density of magnetic material, it is suitable for high-density recording. In particular, the means for forming the magnetic film by the vapor deposition means is said to be preferable because the film formation rate is higher than that by sputtering.

An apparatus for manufacturing a magnetic recording medium by such a vapor deposition means is generally constructed as shown in FIG. In FIG. 12, 31 is a cooling can, 32 is a polyethylene terephthalate (PET) film supply side roll, 33 is a PET film winding side roll, 34
Is a shielding plate, 35 is a crucible, 36 is a magnetic alloy, and 37 is a vacuum container.

After evacuating the inside of the vacuum container 37 to a predetermined degree of vacuum, an electron gun (not shown) is operated to heat and evaporate the magnetic alloy 36 in the crucible 35, and PE
A magnetic recording medium is manufactured by depositing (evaporating) the magnetic alloy 36 on the T film. By the way, if an oxide or the like floats on the liquid surface of the magnetic alloy 36 melted in the crucible 35 during this work, the suspended matter may cause a serious obstacle.

That is, when the floating substance is irradiated with an electron beam from an electron gun, the floating substance has a high melting point and thus is not easily melted and is heated to a high temperature. Then, when the liquid comes into contact with the surrounding liquid, the liquid rapidly evaporates, so that the scattering of the droplets is induced. The droplets thus scattered are called splash and adhere to the PET film, which is the material to be vapor-deposited, to generate foreign matter in the form of protrusions.・ It may cause defects such as failure to reproduce.

Contamination of the inside of the apparatus by the scattered droplets is also a serious problem, which makes maintenance extremely troublesome. In addition, if there is a suspended substance, evaporation from this portion is eliminated, so that the amount of evaporated particles deposited on the PET film decreases, defects occur in the deposition of magnetic particles, and a good magnetic film cannot be formed.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the problems as described above, and an object of the present invention is to effectively remove oxides in a crucible from an evaporation portion, and to eliminate suspended matter. The scattering of liquid droplets caused by this is suppressed, the waste of materials is small, the adhesion of foreign matter is possible, and a uniform thin film can be formed, and the inside of the device is unlikely to be contaminated.
An object of the present invention is to provide a thin film forming apparatus that is easy to maintain.

An object of the present invention is a thin film forming apparatus for forming a thin film by evaporating a material contained in a container and depositing the material on a support, which comprises tilting means for tilting the container. This is achieved by a thin film forming apparatus characterized by the following. Incidentally, the tilting means in this thin film forming apparatus is configured such that, for example, the container is supported by a rotating shaft, the driving means is connected to the rotating shaft, and the container is rocked by the action of the driving means, or The container may be configured to support a single point on the bottom surface of the container as a fulcrum, and to rotate the container around the fulcrum while being in contact with the bottom surface so that the container is tilted by the motion of the rotor.

The inclination of the container by the tilting means as described above is preferably 3 to 45 °. Further, in order to enhance the efficiency of removing suspended matters such as oxides due to the tilting of the container by the tilting means, it is preferable that the inner wall surface of the container is provided with a convex surface such as a flange.

With the above-mentioned structure, the oxides and the like generated when the material is melted adhere to the wall surface of the container when the container is tilted and are removed from the central part (evaporating part). Become so. Therefore, there is no obstacle caused by the presence of the suspended matter, that is, no splash is generated, and no protrusion-like foreign matter is generated on the material to be vapor-deposited. or,
The evaporating part is not covered with suspended matter,
Since evaporation continues, the deposited film is uniform and defect-free. In this way, since a thin film having a uniform thickness and no protrusions is formed, it is possible to efficiently obtain a high-quality magnetic recording medium having good running properties and excellent recording / reproducing characteristics.

Further, since the scattering of droplets is prevented, the state of contamination inside the apparatus is greatly reduced, and therefore the number of maintenances such as cleaning work is small, and the maintenance itself is simple, and an expensive material is used. It will be possible to reduce the waste of money.

[0013]

1 to 8 relate to a first embodiment of a thin film forming apparatus of the present invention. FIG. 1 is a schematic view of the thin film forming apparatus,
2 is a front view of an essential part (crucible part) of the thin film forming apparatus, FIG. 3 is a sectional view of an essential part (crucible part) of the thin film forming apparatus, and FIGS. 4 to 8 are schematic sectional views showing the operation of the apparatus.

In each drawing, 1 is a cooling can, 2 is a roll on the side of a non-magnetic support 21 such as a PET film, 3 is a roll on the side of the support 21, 4 is a shielding plate, and 5 is Co-Ni. A magnetic alloy 6 and the like, 6 is a vacuum container, and since these parts are conventionally known, detailed description thereof will be omitted. 7
Is a crucible, for example, MgO, ZrO, BeO, Al
₂ O ₃ , Si ₃ N ₄ , BN, ThO ₂ , CaO, SiO
_A carbon-based fiber material, especially a carbon-based fiber cloth, is placed between an inner mold and an outer mold, which are molded using a ceramic material such as ₂ into a predetermined shape.
It is constructed by firing.

Reference numerals 8a and 8b are flanges provided on the inner wall surface of the crucible 7. The flanges 8a and 8b have a substantially L-shaped cross section as seen from FIG. 2, and a molten magnetic alloy. A mesh-like material is used in order to pass through and filter out only solids such as oxides. A coil for induction heating is arranged at a predetermined position of the crucible 7, the magnetic alloy 5 in the crucible 7 is preheated, and when an electron beam from an electron gun (not shown) is irradiated. , Evaporation will start immediately from that part.

Reference numeral 9 denotes a fan-shaped gear attached to the bottom of the crucible 7, and 10 denotes a gear meshing with the fan-shaped gear 9. The motor 11 installed outside the vacuum container 6 causes the crucible 7 to be inclined in a predetermined direction. It is configured. When the crucible 7 is tilted by a certain angle, the motor 11 is controlled to rotate in the reverse direction. Numerals 12 and 13 are columns for supporting the crucible 7.

In the apparatus constructed as described above, the inside of the vacuum vessel 6 is evacuated to a predetermined degree of vacuum, and then the electron gun is operated to evaporate the magnetic alloy 5 in the crucible 7 and PET.
When the work of vapor deposition of the magnetic alloy 5 on the support 21 such as a film is started, a floating substance S made of oxide or the like is generated, and FIG.
As shown in, convection collects near the wall surface of the crucible 7.

Here, when the motor 11 is operated and the crucible 7 is tilted to the right as shown in FIG. 5, the right flange 8a is immersed in the liquid. From this state, when the crucible 7 is returned to the original state as shown in FIG.
Strained by and left on the right flange 8a. Next, when the crucible 7 is tilted to the left as shown in FIG. 7, the left flange 8b is immersed in the liquid, and then the crucible 7 is returned to its original state as shown in FIG. It is strained by the flange 8b and remains on the right flange 8b.

In this way, the suspended matter S is removed from the liquid and the clean state of the liquid is maintained at all times, so that splash is unlikely to occur and foreign matter does not adhere to the support 21. It is possible to obtain a product having good running characteristics during recording and reproduction. Moreover, the evaporation effect in the center is not disturbed by the suspended matter S,
Therefore, there is no defect in the deposited magnetic particles, and a uniform magnetic film is formed.

Further, since the inside of the apparatus is slightly contaminated, the maintenance is easy and the waste of materials is small.
Here, FIG. 9 shows a schematic sectional view of a magnetic recording medium obtained by the thin film forming apparatus of the present invention. In FIG. 9, 21 is a non-magnetic support, and this support 21 is made of polyester such as PET, polyamide, polyimide, polysulfone, polycarbonate, olefin resin such as polypropylene, cellulose resin, vinyl chloride resin. Polymer materials such as resins, inorganic materials such as glass and ceramics, and metal materials such as aluminum alloys are used.

An undercoat layer 22 for improving the adhesion of the magnetic layer is provided on the surface of the support 21. That is, to improve the adhesion of the magnetic layer formed by the oblique deposition method by appropriately roughening the surface roughness, and further to improve the running property by making the surface roughness of the magnetic recording medium surface moderate. For example, the thickness including particles such as SiO ₂ is 0.
The undercoat layer 22 is formed by providing a coating film having a thickness of 005 to 0.1 μm.

The magnetic layer 23 is provided on the undercoat layer 22 by the thin film forming apparatus described above. For example, 1
In a vacuum atmosphere of about 0 ⁻⁴ to 10 ⁻⁶ Torr, a ferromagnetic metal material is evaporated by resistance heating, high frequency heating, electron beam heating, etc., and evaporated on the surface of the undercoat layer 22 of the support 21 to obtain magnetic properties. The layer 23 is formed with a thickness of 0.04 to 1 μm. Examples of the material for forming the magnetic layer 23 include metals such as Fe, Co, and Ni, as well as Co—Ni alloys,
Co-Pt alloy, Co-Ni-Pt alloy, Fe-Co alloy, Fe-Ni alloy, Fe-Co-Ni alloy, Fe-C
Examples thereof include o-B alloys, Co-Ni-Fe-B alloys, Co-Cr alloys, and alloys containing a metal such as Al.

At the time of forming the magnetic layer 23, oxygen is supplied to the vapor deposition portion and is forcedly oxidized to oxidize the surface layer portion of the magnetic layer 23 to form a protective layer 24 of an oxide film. The thickness of the protective layer 24 composed of this oxide film is about several tens of liters, and an oxide film of this thickness may be composed of natural oxidation. It is not necessary to take the means of.

Reference numeral 25 is a lubricant layer provided on the protective layer 24 made of an oxide film. That is, a coating material containing a lubricant, for example, fluorine perfluoropolyether (grade: FOMBLIN Z DIAC carboxyl group-modified, manufactured by Nippon Montedison Co., Ltd.) is added to a fluorine inert liquid (Fluorinert, FC-84, Sumitomo 3M Co., Ltd.). .1
The lubricant layer 25 is provided with a thickness of about 5 to 50 Å, preferably about 10 to 30 Å, by applying a coating solution diluted and dispersed so as to have a concentration of 5% by a predetermined means such as a die coating method.

Reference numeral 26 is a back coat layer provided on the other surface of the support 21 and containing carbon black or the like.
10 and 11 show a second embodiment of the thin film forming apparatus of the present invention. FIG. 9 is a perspective view of a main part (crucible part) of the thin film forming apparatus, and FIG. 10 is a main part of the thin film forming apparatus (crucible). Part)
FIG.

In the second embodiment as well, the basic structure of the entire apparatus is substantially the same as that of the first embodiment described above, and therefore only the essential part (crucible part) will be described. Figure 1
In FIG. 0 and FIG. 11, 14 is a crucible, and 14 a is a guide groove provided on the bottom surface of the crucible 14. 15 is a crucible 14
A column joint that supports the, and a ball joint, a universal joint, or the like is interposed between the crucible 14 and the column 15.

Reference numeral 16 is an annular rail, and as shown in FIG. 11, a guide groove 16a is formed on the upper surface. 1
Reference numerals 7 and 18 denote frustoconical rollers arranged between the bottom of the crucible 14 and the annular rail 16, and annular protrusions 17a and 18a corresponding to the guide groove 14a of the crucible 14 and the guide groove 16a of the annular rail 16. Are formed respectively.

The rollers 17 and 18 are constructed so as to run on the annular rail 16 by a driving means (not shown). Reference numeral 19 denotes an annular flange provided on the inner wall surface of the crucible 14.
As can be seen from FIG. 11, the reference numeral 9 has a substantially L-shaped cross section, and is made of a mesh for filtering only the suspended matter.

In the thin film forming apparatus constructed as described above, the rollers 17 and 18 travel on the annular rail 16 so that the liquid in the crucible 14 makes a wave-like motion. The traveling speed of the rollers 17 and 18 is
Depending on the size of the crucible 14, the inclination of the crucible 14, the viscosity of the material, the output of the electron gun, etc., for example, when the diameter of the crucible is 80 mm and the inclination is 10 °, the maximum is about 60 rpm. To

With the above-mentioned configuration, the first
The suspended matter is removed as in the example. Therefore, the droplets are prevented from scattering, the high quality product as described in detail in the first embodiment can be efficiently obtained, the device is less likely to be contaminated, and the material is not wasted.

[0031]

[Effects] According to the present invention, suspended matter in the crucible can be effectively removed, problems such as splash caused by the suspended matter can be solved, and foreign matters are not attached and defect-free high quality Various products can be obtained efficiently,
Further, since the device is slightly contaminated, the maintenance is easy and the waste of materials is small.

[Brief description of drawings]

FIG. 1 is a schematic view of a thin film forming apparatus (first embodiment) of the present invention.

FIG. 2 is a front view of a main part (crucible part) of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 3 is a sectional view of a main part (crucible part) of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 4 is a schematic cross-sectional view showing the operation of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 5 is a schematic cross-sectional view showing the operation of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 6 is a schematic cross-sectional view showing the operation of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 7 is a schematic cross-sectional view showing the operation of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 8 is a schematic cross-sectional view showing the operation of the thin film forming apparatus (first embodiment) of the present invention.

FIG. 9 is a cross-sectional view of a product obtained by the thin film forming apparatus of the present invention.

FIG. 10 is a perspective view of a main part (crucible part) of a thin film forming apparatus (second embodiment) of the present invention.

FIG. 11 is a sectional view of a main part (crucible part) of a thin film forming apparatus (second embodiment) of the present invention.

FIG. 12 is a schematic view of a conventional thin film forming apparatus.

[Explanation of symbols]

 1 Cooling Can 5 Magnetic Alloy 6 Vacuum Container 7 Crucible 8a, 8b Flange 9 Fan Gear 10 Gear 11 Motor S Floating Material

Front Page Continuation (72) Inventor Akira Shiga 2606 Akabane, Kai-cho, Haga-gun, Tochigi Prefecture Kao Corporation Company Information Science Laboratory

Claims (5)

[Claims] 1. A thin film forming apparatus for forming a thin film by evaporating a material contained in a container and depositing the material on a support, comprising tilting means for tilting the container. Characteristic thin film forming apparatus. 2. The container is supported by a rotary shaft, and a drive means is connected to the rotary shaft, and the container is configured to swing by the action of the drive means. The thin film forming apparatus according to claim 1. 3. The container is provided with a rotating body which is supported by using one point on the bottom surface as a fulcrum and rotates around the fulcrum while being in contact with the bottom surface, and the container is tilted by the motion of the rotating body. The thin film forming apparatus according to claim 1, wherein the thin film forming apparatus is configured to: 4. The inclination of the container by the tilting means is 3 to 45.
4. The thin film forming apparatus according to claim 1, wherein the thin film forming apparatus has a temperature of 50 °. 5. The thin film forming apparatus according to claim 1, wherein the inner wall surface of the container is provided with a convex surface.