JPH0578822A - Production of thin film - Google Patents

Abstract

PURPOSE:To form the thin film of metal in vacuum without thermal damage of a supporting base body such as a polymer base plate by solving such a problem that the supporting base body receives thermal damage and the thin film is not formed when the adhesive properties of both the support. ing base body and a cylindrical can are deficient in the case of forming the thin film on the supporting base body in a method for producing the thin film. CONSTITUTION:In the case of forming a thin film directly or via a primary coat on a long-sized supporting base body 1 while running the supporting base body 1 along a cylindrical can 3 in vacuum, the surface of this cylindrical can 3 is covered with an insulator 13 and irradiated with charged particles 15 such as electron beams and ion beams before the thin film is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a thin film used in magnetic recording media, decorative wrapping paper and the like.

[0002]

2. Description of the Related Art In modern society, thin films play a large role, and it is required to form a large area metal thin film at high speed and at low cost in decorative packaging papers and magnetic recording media in the range of use. .. As a typical method for forming a large-area metal thin film, there is a continuous vapor deposition method to which a vacuum vapor deposition method is applied.

FIG. 2 shows an apparatus used in a conventional method for manufacturing a thin film. As shown in the figure, the apparatus is a cylinder in which a long supporting substrate 1 is unrolled from a supply roll 2 in a vacuum. This is a method of irradiating an electron beam 4 at a desired vapor incident angle while running along a can 3 to deposit a metal thin film from an evaporation source 5, and then winding the metal thin film on a winding roll 6. This method is used. Thereby, a metal thin film can be formed continuously at high speed. For example, in the manufacture of a magnetic tape, an evaporation source filled with a magnetic material while a supporting substrate 1 made of a polymer film substrate such as polyethylene terephthalate (PET) in FIG. 2 is running along the circumferential surface of a cylindrical can 3. The magnetic tape can be mass-produced by subjecting the magnetic layer 5 to electron beam evaporation.
In the figure, 7 is the traveling direction of the support base 1, 8 is a mask having an opening 9, and 10 is a vacuum chamber that is evacuated by an exhaust system 11.

[0004]

When a metal thin film is formed by a continuous method, the adhesion between the supporting substrate 1 and the cylindrical can 3 is a very important problem for stable metal thin film formation. That is, since the thin film is formed at a high speed, the heat of condensation of the atoms adhering to the supporting base 1 is very large, and if the adhesion between the supporting base 1 and the cylindrical can 3 is insufficient, the supporting base 1 will be damaged by heat. There is a challenge to receive.

It is also common practice to smooth the surface of the cylindrical can 3 in order to allow sufficient heat to escape from the support base 1 to the cylindrical can 3. Furthermore, it is also effective to stick the support base 1 and the cylindrical can 3 by electrostatic attraction. As a means for this, as shown in FIG.
It has been proposed to irradiate the surface of the substrate with the electron beam 12, but there is a problem that the supporting substrate 1 is deteriorated by the adverse effect of electron implantation into the supporting substrate 1, particularly repeated electron irradiation in the case of a laminated film.

The present invention is intended to solve the above problems,
It is an object of the present invention to provide a thin film manufacturing method capable of forming a metal thin film or the like without damaging a supporting substrate.

[0007]

In order to achieve the above object, the present invention is directed to a metal thin film directly or on an underlayer while moving a long supporting substrate along a cylindrical can in a vacuum. In the method for producing a thin film for forming a metal film, the surface of the cylindrical can is covered with an insulator, and the surface of the cylindrical can is irradiated with charged particles prior to the formation of the metal thin film.

[0008]

According to the present invention, therefore, by irradiating the cylindrical can whose surface is an insulator with charged particles, the surface of the cylindrical can becomes charged, and the supporting substrate is caused to travel along the cylindrical can. As a result, the supporting substrate is brought into close contact with the surface of the cylindrical can by electrostatic attraction. As a result, a metal thin film can be formed without heat damage to the supporting substrate during vapor deposition. Further, since the cylindrical can is irradiated with the charged particles, it is possible to prevent the deterioration of the supporting substrate due to the repeated irradiation of the charged particles even when the metal thin film is laminated.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. 1 and FIG. 2 and FIG. As shown in the figure, a support base 1 made of a long polymer substrate unrolled along a traveling direction 7 from a supply roll 2 in a vacuum chamber 10 evacuated by an exhaust system 11 is for forming a metal thin film. After the metal thin film is vapor-deposited from the opening 9 of the mask 8 by the evaporation source 5 which is irradiated with the electron beam 4 while traveling along the peripheral surface of the cylindrical can 3, it is wound up by the winding roll 6. .. At this time, the peripheral surface of the cylindrical can 3 is covered with the insulator 13, and this portion is irradiated with the electron beam 15 from the contact electron beam source 14. The multi-layering of the metal thin film is performed by repeating this process.

(Example 1) The supporting substrate 1 has a thickness of 10 μm.
A m-th polyethylene terephthalate substrate (hereinafter referred to as a PET substrate) was used to perform vapor deposition while introducing oxygen gas, thereby forming a 200 nm-thick Co—O metal thin film (not shown) as a metal thin film. Also, the cylindrical can 3
The peripheral surface of the insulator is made of SiO _{2 and} has a thickness of 50 μm.
Coated with. While irradiating the electron beam 15 from the contact electron beam source 14 to the cylindrical can 3 at a distance of 30 cm, vapor deposition was performed by changing the temperature of the cylindrical can 3 at a film deposition rate of 400 nm / s.

When the temperature of the cylindrical can 3 was 10 ° C. or lower, the Co—O layer could be vapor-deposited when the electron beam 15 was not irradiated, but when the temperature of the cylindrical can 3 exceeded 10 ° C., the PET substrate 1 was formed. When the temperature was 30 ° C. or higher, the PET substrate 1 was decomposed and vapor deposition could not be performed at all.

On the other hand, when the electron beam 15 is irradiated using the contact electron beam source 14, the temperature of the cylindrical can 3 is stabilized up to 30 ° C. by setting the acceleration voltage to 2 kV and the beam current to 200 mA, for example. It was possible to perform various vapor depositions. A similar experiment was conducted on the Si surface of the cylindrical can 3.
When only the thickness of the insulator 13 made of O ₂ was changed, the temperature of the cylindrical can 3 capable of vapor deposition was 15 ° C when the thickness of the insulator 13 was 10 μm, and 20 ° C when it was 20 μm. It was

(Embodiment 2) The same PET substrate as that used in the embodiment is used as the supporting base 1, and vapor deposition is carried out while introducing oxygen gas to form a metal thin film of Co-O having a thickness of 100 nm.
A metal thin film was formed. By repeating this twice, a Co-O metal thin film of 200 nm was formed.

The peripheral surface of the cylindrical can 3 is covered with an insulator 13 made of SiO _{2 having a} thickness of 50 μm, and a film is formed by irradiating the electron beam 15 from a distance 30 cm from the electron beam source 14 for adhesion to the cylindrical can 3. Deposition rate 400 nm /
Vapor deposition was performed by changing the cylindrical can temperature at s.

When the temperature of the cylindrical can 3 at the time of forming the second layer is not higher than 0 ° C. when the electron beam 15 is not irradiated, Co-
Deposition of the O layer was completed, but if the temperature exceeds 0 ° C, P
When the ET substrate 1 was thermally damaged and the temperature of the cylindrical can 3 at the time of forming the second layer was 15 ° C. or higher, the PET substrate 1 was decomposed and vapor deposition could not be performed at all. On the other hand, when the electron beam 15 is irradiated using the contact electron beam source 14, the temperature of the cylindrical can 3 at the time of forming the second layer is 35 ° by setting the acceleration voltage to 2 kV and the beam current to 200 mA, for example. It was possible to perform stable vapor deposition up to C.

(Embodiment 3) The supporting substrate 1 has a thickness of 10 μm.
m polyimide substrate (hereinafter referred to as PI substrate)
A Co-Cr metal thin film having a thickness of 200 nm was formed as the metal thin film. The peripheral surface of the cylindrical can 3 has a thickness of 50 μm.
Was covered with an insulator 13 made of SiO ₂ . A film deposition rate of 600 nm while irradiating the electron beam 15 from a distance 30 cm from the contact electron beam source 14 to the cylindrical can 3.
The vapor deposition was performed by changing the temperature of the cylindrical can 3 at / s.

When the electron beam 15 was not irradiated, the Co-Cr layer could be vapor-deposited when the temperature of the cylindrical can 3 was 50 ° C. or lower, but when the temperature exceeded 50 ° C., the PI substrate 1
When the temperature of the cylindrical can 3 was 80 ° C. or higher, the PI substrate 1 was decomposed and vapor deposition could not be performed at all.
On the other hand, when the electron beam 15 is irradiated by using the contact electron beam source 14, the cylindrical can 3 is formed by setting the acceleration voltage to 2 kV and the beam current to 200 mA, for example.
It was possible to perform stable vapor deposition up to a temperature of 250 ° C.

Example 4 As the supporting substrate 1, the same PI substrate as in Example 3 was used, and a Co-Cr metal thin film having a thickness of 100 nm was formed as a metal thin film. By repeating this twice, a 200 nm Co-Cr metal thin film was formed. The peripheral surface of the cylindrical can 3 is made of SiO _{2 having a} thickness of 50 μm.
Electron beam source 14 for adhesion, which is covered with an insulator 13 made of
The vapor deposition was performed by changing the temperature of the cylindrical can 3 at a film deposition rate of 600 nm / s while irradiating the electron beam 15 from a distance of 30 cm from the cylindrical can 3 to the cylindrical can 3.

When the temperature of the cylindrical can 3 at the time of forming the second layer is not higher than 30 ° C. when the electron beam 15 is not irradiated, Co
-Although the Cr layer was vapor-deposited, if the temperature exceeded 30 ° C, the PI substrate 1 was thermally damaged, and if the temperature of the cylindrical can 3 during the formation of the second layer was 50 ° C or higher, the PI substrate 1 was formed. Was decomposed and no vapor deposition was possible. On the other hand, when the electron beam 15 is irradiated using the contact electron beam source 14, the temperature of the cylindrical can 3 at the time of forming the second layer is 300 ° by setting the acceleration voltage to 2 kV and the beam current to 200 mA. It was possible to perform stable vapor deposition up to C.

(Embodiment 5) The supporting substrate 1 has a thickness of 6 μm.
Using the same PET substrate as in Example 1 having Example 1, a Co—O metal thin film having a thickness of 50 nm was formed as a metal thin film. By repeating this 4 times, a 200 nm Co-O metal thin film was formed. The peripheral surface of the cylindrical can 3 has a thickness of 50 μm.
Of SiO ₂ is covered with an insulator 13, and the temperature of the cylindrical can 3 is changed at a film deposition rate of 400 nm / s while irradiating the electron beam 15 from a distance of 30 cm from the contact electron beam source 14 to the cylindrical can 3. Vapor deposition was performed.

When the electron beam 15 was not irradiated, the PET substrate 1 was severely damaged by heat even when the temperature of the cylindrical can 3 at the time of forming the second layer was set to 0 ° C., and a metal thin film could not be formed. Further, when four layers are laminated by the conventional manufacturing method shown in FIG. 3, when the temperature of the cylindrical can 3 exceeds 15 ° C., the PET substrate 1 is laminated as the lamination is repeated.
However, when the method of the present invention is used, even if the temperature of the cylindrical can 3 is 25 ° C.
The lamination of layers could be done without thermal damage to the PET substrate 1.

(Embodiment 6) The same PET substrate as in Embodiment 1 is used as the supporting base 1, and vapor deposition is carried out while introducing oxygen gas to form a metal thin film of Co-- having a thickness of 200 nm.
An O metal thin film was formed. The peripheral surface of the cylindrical can 3 was covered with an insulator 12 made of SiO _{2 having a} thickness of 50 μm. An ion source is used instead of the contact electron beam source 14 shown in FIG. 1, and the distance 3 from the ion source to the cylindrical can 3 is set.
Cylindrical can 3 at a film deposition rate of 400 nm / s while irradiating an ion beam from 0 cm instead of the electron beam 15.
The vapor deposition was performed by changing the temperature of.

When the temperature of the cylindrical can 3 was 10 ° C. or less, the Co—O layer could be vapor-deposited when the ion beam was not irradiated, but when the temperature of the cylindrical can 3 exceeded 10 ° C.
When the ET substrate 1 was thermally damaged and the temperature of the cylindrical can 3 was 30 ° C. or higher, the PET substrate 1 was decomposed and vapor deposition could not be performed at all. On the other hand, when the ion beam is irradiated, for example, the beam voltage is 500 V and the beam current is 100 m.
By setting A, the temperature of the cylindrical can 3 is 25 ° C.
It was possible to perform stable vapor deposition.

As described above, according to the above-mentioned embodiment, when the metal thin film is formed while the long supporting substrate 1 is moved along the cylindrical can 3 in vacuum, the surface of the cylindrical can 3 is made into an insulator. By covering the cylindrical can 3 with 13 and irradiating the surface of the cylindrical can 3 with charged particles such as an electron beam 15 or an ion beam, the adhesion between the supporting base 1 and the cylindrical can 3 is increased, and the thermal damage to the supporting base 1 is prevented. The size can be reduced to form a metal thin film.

The adhesion between the supporting base 1 and the cylindrical can 3 is due to the electrostatic attraction between the insulator 13 on the surface of the cylindrical can 3 and the metal thin film layer formed on the supporting base 1. Therefore, when the metal thin film layer is previously formed on the support base 1, the support base 1 and the cylindrical can 3 are in a strong contact state from the initial stage of forming the metal thin film layer, but the metal thin film is previously formed on the support base 1. When the layer is not formed, the metal thin film layer is formed to some extent by the film formation in the vacuum process, and thereafter the support base 1 and the cylindrical can 3 are brought into close contact with each other by electrostatic attraction.

Therefore, the effect of preventing heat damage is greater when the metal thin film layer is previously formed on the support base 1. Therefore, if anything, the present invention exerts a greater effect when the multilayer films are laminated, and the results of (Example 1) and (Example 2) also suggest this. The same applies to the comparison between (Example 3) and (Example 4).

Further, at that time, if the thickness of the insulator 13 on the surface of the cylindrical can 3 is large to some extent, stronger adhesion can be obtained, and vapor deposition is possible even if the temperature of the cylindrical can 3 is high (implementation). It can be seen from the result of Example 1). This is considered to be due to the following reasons.

The electrostatic attraction due to the irradiation of the charged particles such as the electron beam 15 and the ion beam is caused by the insulator 13 and the cylindrical can 3.
Of the latter, which acts both between the body of the insulator and between the insulator 13 and the metal thin film layer on the surface of the support substrate 1, but the latter component of electrostatic attraction that actually contributes to the prevention of thermal damage increases as the thickness of the insulator 13 increases. It seems to be.

Therefore, the thickness of the insulator 13 is determined by the support base 1
It is more preferable that the thickness is equal to or more than the thickness.

Although only the case where polyethylene terephthalate (PET) / polyimide (PI) is used as the supporting substrate 1 has been described as an example, other substrates such as polyethylene naphthalate, polyamide, and aramid are used. In this case, the same effect can be obtained.

Co-O and Co-C are used as the metal thin film.
Although only the case of forming r has been described, it goes without saying that the present invention is also effective when forming other magnetic materials, metal thin films other than magnetic materials, and non-metal thin films.

As the vacuum film forming method, only the vacuum evaporation method has been described, but the vacuum film forming method other than the vacuum evaporation method such as the sputtering method, the ion plating method and the cluster ion beam evaporation method is also effective. Needless to say.

[0033]

As is apparent from the above embodiments, according to the present invention, the surface of the cylindrical can is covered with an insulator, and when the metal thin film is formed on the supporting substrate, the surface of the cylindrical can is irradiated with charged particles. Therefore, the thin film can be formed without causing thermal damage to the supporting substrate.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional front view of an apparatus for carrying out a thin film manufacturing method according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional front view of an apparatus used in a conventional thin film manufacturing method.

FIG. 3 is a partial sectional front view of the other device.

[Explanation of symbols]

 1 Support Substrate 3 Cylindrical Can 10 Vacuum Chamber 13 Insulator 15 Electron Beam (Charged Particle)

Claims (3)

[Claims] 1. A method for producing a thin film, which comprises forming a metal thin film directly on the supporting base or through an underlayer while running a long supporting base along a cylindrical can in vacuum.
A method for producing a thin film, characterized in that the surface of the cylindrical can is covered with an insulator, and the surface of the cylindrical can is irradiated with charged particles prior to the formation of the metal thin film. 2. The method for producing a thin film according to claim 1, wherein the thickness of the insulator covering the surface of the cylindrical can is equal to or more than the thickness of the supporting substrate. 3. The method for producing a thin film according to claim 1, wherein a metal thin film layer is previously formed as a base layer on the supporting substrate.