JPH0223528A - Production of thin film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thin film manufacturing method for continuously forming a thin film on a polymer film by vacuum evaporation.

BACKGROUND ART Conventionally, vacuum evaporation has been known as a method for forming metal thin films and oxide thin films on polymer films with high productivity. FIG. 5 is a side view schematically showing an example of the inside of a vacuum evaporation apparatus commonly used in production. The polymer film 1 runs along the circumferential surface of the cylindrical can 2. A thin film is formed on this polymer film 1 by the evaporation source 5 .

3.4 is a bobbin for winding the polymer film l. As the evaporation source 5, a resistance heating evaporation source, an induction heating evaporation source, an electron beam evaporation source, etc. are used. Evaporation source 5 and cylindrical can 2
A shielding plate 6 is disposed between the evaporation source 5 and the evaporation source 5 to prevent the vapor 7 evaporated from the evaporation source 5 from adhering to unnecessary parts. The shielding plate 6 has a frontage as shown by S,
The vapor that has passed through this opening S adheres onto the polymer film l.

Problems to be Solved by the Invention By the way, polymer films on which metal thin films or oxide thin films are formed are used in capacitors, magnetic tapes, and the like. In these applications, it is necessary to use a thin polymer film. In fact, polymer films with a thickness of about 2 μm are used for capacitors, and about 10 μm for magnetic tapes. However, when a thin film is formed on such a thin polymer film using the vacuum evaporation apparatus shown in FIG. A problem arises.

An object of the present invention is to provide a thin film manufacturing method that solves the problems of the prior art.

Means for Solving Problems The method for manufacturing a thin film according to the present invention is such that when a thin film is formed by vacuum evaporation on a polymer film running along the circumferential surface of a cylindrical can, after the thin film is formed, , irradiating the polymer film on the open surface of the cylindrical can with ions and electrons from an ion gun, or in the vicinity of a peeling site where the polymer film after thin film formation separates from the peripheral surface of the cylindrical can; The polymer film is irradiated with ions and electrons from an ion gun from the back surface of the polymer film (the surface opposite to the surface on which the thin film is formed).

Function: According to the thin film manufacturing method of the present invention, since the electrostatic charge on the polymer film after the thin film is formed can be removed, the running of the polymer film is stable and it is possible to form a wrinkle-free thin film.

Embodiments Below, embodiments of the present invention will be described with reference to FIGS. 1 to 4.

1 and 2 are similar to the conventional vacuum evaporation apparatus shown in FIG. 5, except that the ion gun 8 is arranged. In addition, FIG. 1 and FIG. 2 show an example in which the polymer film 1 runs in the direction of arrow A, and 3 is an unwinding bobbin and 4 is a winding bobbin. The ion gun 8 is similar to those commonly used in ion beam sputtering, ion milling, substrate pretreatment, and the like. In FIG. 1, the ions and electrons from the ion gun 8 are emitted toward the polymer film after the thin film is formed, which is running around the circumferential surface of the cylindrical can 2.
In the figure, the polymer film after the thin film formation is emitted toward the back surface of the polymer film in the vicinity of the peeling site where it separates from the peripheral surface of the cylindrical can 2. Here, it is important that the ion gun 8 emits not only ions but also electrons.

A schematic diagram of the ion gun 8 is shown in FIG. Accelerated ions 12 of Ar, N2, N2.02, etc. come out from the grid 10 of the ion gun 8. Note that Ar is generally used.

Reference numeral 11 denotes a neutralizer, and electrons 13 are generated by passing a current through this.

Reference numeral 9 in FIGS. 1 and 2 indicates a mixture of ions 12 and electrons 13.

Specific examples will be described below.

Example 1 A specific example will be described in which a Co--Cr film, which is a thin metal film, is formed using a vacuum evaporation apparatus shown in FIG. 2 using a polyimide film having a thickness of 8 μm as a polymer film. Note that the Co--Cr film is suitable as a high-density magnetic recording medium.

As the evaporation source 5, an electron beam evaporation source was used.

First, film formation was performed using a conventional method. That is, without operating the ion gun 8, the polyimide film was run at a speed of 10 m/min in the direction of the arrow to form a Co--Cr film with a thickness of 0.2 μm. In this method, the cylindrical can 2
From polyimide film! Wrinkles occurred in the polyimide film at the 1ii1i portion, and it was not possible to complete it as a magnetic recording medium.

Next, a film was formed by implementing the method of the present invention.

At this time, a Kaufmann type is used as the ion gun 8,
The acceleration voltage of the ion gun is -300■, and the ion current density is 0.
．． 1 mA/c rn2, the gas introduced into the ion gun is A
r (flow rate was 10 cc/min). Further, a current was applied to the neutralizer 11 to generate electrons. The electron current density was set to O61 mA/cm2, which is almost the same as the ion current density. The polyimide film was run at a speed of 10 m/min in the direction of the arrow to form a Co--Cr film with a thickness of 0.2 μm. According to this method, no wrinkles were generated. Incidentally, wrinkles occurred when the neutralizer was not operated.

Example 2 A specific example will be described in which a polyimide film with a thickness of 8 μm is used as the polymer film and an Al2O3 film, which is an oxide thin film, is formed using the vacuum evaporation apparatus shown in FIG. Note that the Al2O3 film is used as a base layer for the Co--Cr film.

The Al2O3 film is formed by a so-called reactive vapor deposition method in which AI and 02 are reacted to form a film. In order to carry out reactive vapor deposition, it is necessary to direct the reactive gas to the evaporation section. Figure 4 shows the situation. 14 is a pipe for directing the reaction gas to the evaporation section. At is evaporated using an electron beam evaporation source as evaporation R5. Introduce 02 from pipe 14 and A
An Al2O3 film is formed on the polymer film l by reacting with I atoms.

First, film formation was performed using a conventional method. That is, without operating the ion gun 8, the polyimide film was run at a speed of 10 m/min in the direction of arrow A, and the film thickness was 0.02 μm.
An Al2O3 film was formed. In this method, wrinkles occur in the polyimide film at the part where it is peeled off from the cylindrical can 2, and Co-Cr
evaporation was difficult.

Next, a film was formed by implementing the method of the present invention. At this time, a Kaufmann type ion gun 8 is used, the acceleration voltage of the ion gun is -1000 V, and the ion current density is 0.1 m.
A/am2, the gas introduced into the ion gun is Ar (flow rate is 10
cc/min). Further, a current was applied to the neutralizer 11 to generate electrons. The electron current density was set to 0.1 mA/cm2, which is almost the same as the ion current density. The polyimide film was run at a speed of 10 m/min in the direction of the arrow to form an Al2ha film with a thickness of 0.02 μm. According to this method, no wrinkles occur at all, and as a post-process, Example 1
A Co--Cr film could be deposited by the method described in . Incidentally, wrinkles occurred when the neutralizer was not operated.

As explained in the above two examples, the reason why the present invention has a remarkable improvement effect on wrinkles as compared to the conventional method is thought to be due to the removal of electrical charges on the polymer film by the ion gun. This will be explained in detail. Polymer films are generally very susceptible to charging. Particularly when continuously forming a thin film, the polymer film becomes significantly charged. For example, even if the polymer film l is not charged on the cylindrical can 2 before the thin film is formed, after the thin film is formed, the polymer film l is charged by frictional charging, contact charging, or reflected electrons from an electron beam evaporation source. becomes electrically charged. In this charged state, the polymer film 1 is placed in the cylindrical can 2.
When the polymer film 1 is peeled off from the cylindrical can 2, the polymer film 1 is not peeled off from the cylindrical can 2 in the same way, and wrinkles occur.

On the other hand, in the method of the present invention, when the polymer film l is running on the cylindrical can 2 or is about to be peeled off, the polymer film 1 is removed by ions and electrons emitted from the ion gun 8. Static electricity is removed. As a result, the polymer film 1 is peeled off from the cylindrical can 2 in a -like manner, which is thought to prevent wrinkles from forming.

In the above specific examples, an Al2O3 film is used as the oxide thin film on the polyimide film, and a Co-Cr film is used as the metal thin film.
Although an example in which a film is vapor-deposited has been described, the same effect as described above can be obtained even if a polyamide film, a polyetherimide film, a boethylene terephthalate film, a polyethylene naphthalate film, etc. are used instead of a polyimide film as the polymer film. Also, as a thin film, Al2O3
Membranes and C.

The same procedure as described above is also applied when forming an outer oxide thin film or a metal thin film outside the -Cr film. However, neutralizer
It is a necessary condition to operate the ion beam, and unless the polymer film is irradiated with ions and electrons at approximately equal current density, the effects of the present invention will not be seen.

In addition, although the above discussion focused on the example of directly depositing a thin film on a polymer film, it is also possible to use a polymer film as a substrate on which a base layer of a spunide thin film or a base layer of a metal thin film is formed. It is also possible to apply the present invention. In particular, the 2f! By using the above ion and electron irradiation methods together, the scope of application of the present invention is expanded.

In other words, when the effects of ion and electron irradiation are difficult to reach, for example, when the base layer or thin film is thick, or even when the base layer or thin film is metal, ions and electrons cannot be irradiated from both sides of the polymer film. Static electricity can be removed by irradiation.

Effects of the Invention The present invention irradiates the polymer film on the peripheral surface of a cylindrical can with ions and electrons from an ion gun after forming a thin film, or irradiates the polymer film on the circumferential surface of a cylindrical can after forming a thin film. Since the polymer film is irradiated with ions and electrons from an ion gun from the back side of the polymer film near the peeling site away from the peripheral surface, a thin film can be stably produced on a thin polymer film without wrinkles. It is possible

[Brief explanation of the drawing]

FIG. 1 is a side view schematically showing the internal structure of a vacuum evaporation apparatus used in a thin film manufacturing method in one embodiment of the present invention;
The figure is a side view schematically showing the internal structure of a vacuum evaporation apparatus used in a thin film manufacturing method according to another embodiment of the present invention, and FIG. 3 is a side view schematically showing an ion gun used in the thin film manufacturing method. FIG. 4 is a side view schematically showing the internal structure of a vacuum vapor deposition HR used in the reactive vapor deposition method in the thin film manufacturing method, and FIG. 5 is a side view schematically showing the internal structure of a conventional vacuum vapor deposition apparatus. 1... Polymer film, 2... Cylindrical can, 3.
4... Bobbin, 5... Evaporation source, 6... Shielding plate, 7
... Steam, 8... Ion gun, 9... Ions and electrons, 10... War grid, 11... Neutralizer-12-... Ions, 13- - Electrons, 14◆...
Piping, A...arrow, S...every other day. Name of agent: Patent attorney Shigetaka Awano (1 person) Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) When forming a thin film by vacuum deposition on a polymer film running along the circumferential surface of a cylindrical can, after the thin film is formed, the polymer film is on the circumferential surface of the cylindrical can. A method for producing a thin film, which comprises irradiating ions and electrons from an ion gun. (2) When forming a thin film by vacuum evaporation on a polymer film running along the circumferential surface of a cylindrical can, a peeling portion where the polymer film separates from the circumferential surface of the cylindrical can after the thin film has been formed A method for producing a thin film, characterized in that the polymer film is irradiated with ions and electrons from an ion gun from the back surface of the polymer film (the surface opposite to the surface on which the thin film is formed) in the vicinity.