JPH09104968A - Thin film forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film forming device capable of forming a thin film of metal or the like on a band-shaped substrate having many fine ruggedness with tight adhesion and good sticking properties at a high speed. SOLUTION: This thin film forming device is provided with a vacuum vessel 4, a conveying device 6 conveying a band-shaped substrate 2 having many fine ruggedness therein, an arc type evaporating source 14 and an electron beam type evapoprating source 20. The arc type evaporating source 14 evaporates a cathode material 18 by vacuum arc discharge and allows the same to vapor- deposit on the substrate 2. The electron beam type evaporating source 20 is provided on the side below the substrate conveying device 6 than the arc type evaporating source 14, evaporates an evaporating material 22 and allows the same to vapor-deposit on the substrate 2.

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 for forming a thin film of metal or the like on a belt-like substrate having a large number of fine irregularities such as a battery electrode material or a cloth material.

[0002]

2. Description of the Related Art Examples of a base material which is in the form of a strip and has many fine irregularities include, for example, a porous strip material, a mesh strip material, and a cloth material. Nonwoven fabrics are also included in this cloth material.

The substrate 2 shown in FIG. 3 is an enlarged view of an example of a porous strip material, and has a large number of small holes 2a throughout, so that a large number of fine irregularities are three-dimensionally formed. Have

The base material 2 shown in FIG. 4 is an enlarged view of an example of a cloth material, and has many fine irregularities formed by weaving warp threads and weft threads. The mesh strip has a structure similar to this. The non-woven fabric is not woven with threads, but has many fine irregularities on the surface.

An example of the porous strip material is a battery electrode material, and a metal thin film is formed on the surface of the electrode material so as to have conductivity. In addition, a metal thin film such as aluminum is formed on the surface of the cloth material in order to enhance decorativeness and the like.

In a conventional thin film forming apparatus for forming a thin film of a metal or the like on the base material 2 having a strip shape and a large number of fine irregularities as described above, the evaporation source is a target mainly made of a metal by high frequency plasma. A sputtering type evaporation source for sputtering or an electron beam type evaporation source for heating an evaporation material made of metal with an electron beam to evaporate it is used.

[0007]

However, in the above-mentioned sputtering type evaporation source and electron beam type evaporation source, since the kinetic energy of evaporating particles is as small as several eV, the reaction between the evaporating particles and the base material is poor, and therefore the thin film is thin. However, there is a problem that the adhesion is poor.

Further, since the kinetic energy of the vaporized particles is small as described above, the throwing power to the substrate having a large number of fine irregularities is poor, so that a thin film should be uniformly coated on such a substrate. There is a problem that you can not. The "surrounding property" refers to a property in which the vaporized particles surround and adhere not only to the surface but also to the inner part of the concave part or the shadow of the convex part.

Further, in the case of the sputtering type evaporation source, when the film forming rate is increased, there is a problem that the temperature of the base material is remarkably increased by the radiant heat of the plasma and the base material is deformed and damaged.

Therefore, the present invention provides a thin film forming apparatus capable of forming a thin film of a metal or the like on a base material having a band-like shape and a large number of fine irregularities with good adhesion and throwing power and at a high speed. The main purpose is that.

[0011]

A thin film forming apparatus of the present invention comprises a vacuum container, and a transfer device for transferring a strip-shaped substrate having a large number of fine irregularities in the vacuum container.
An arc-type evaporation source attached to the vacuum container to evaporate a cathode material by vacuum arc discharge to deposit it on the substrate, and a substrate transfer in the vacuum container rather than the arc-type evaporation source. And an electron beam evaporation source for evaporating an evaporation material by an electron beam and depositing the evaporation material on the base material.

According to the above structure, after forming a thin film of metal or the like as a base layer on the base material by the arc type evaporation source,
From above, a thin film of metal or the like can be further formed by an electron beam evaporation source. In that case, since the vaporized particles from the arc evaporation source have much higher kinetic energy than the vaporized particles from the electron beam evaporation source, a thin film with good adhesion and throwing power is used as the underlayer. Can be formed. On the other hand, since the electron beam evaporation source can easily obtain a higher vapor deposition rate than the arc evaporation source, it is possible to form a thin film on the underlayer at a high speed.

By combining the arc type evaporation source and the electron beam type evaporation source, which have the respective characteristics described above, the characteristics of both can be utilized together, and a strip-shaped substrate having a large number of fine irregularities can be formed on a substrate such as metal. The thin film can be formed at a high speed with good adhesion and throwing power.

Further, the arc type evaporation source and the electron beam type evaporation source as described above may be arranged on both front and back sides of the base material, respectively. A thin film of metal, etc., with good adhesion and sticking property,
And it can be formed at a high speed.

[0015]

FIG. 1 is a sectional view showing an example of a thin film forming apparatus according to the present invention. This thin film forming device
A vacuum container 4 that is evacuated by a vacuum exhaust device (not shown), and a transfer device 6 that continuously transfers in the vacuum container 4 the base material 2 having the strip shape and the large number of fine irregularities in the arrow A direction. It has and.

In this example, the transport device 6 includes a feed roller 8 that winds the base material 2 and sends it out, a take-up roller 10 that winds the base material 2, and a plurality of rollers 12 that change the transport direction of the base material 2. I have it.

On the wall surface of the vacuum container 4, an arc type evaporation source 14 for evaporating the cathode substance 18 by vacuum arc discharge and depositing it on the substrate 2 being conveyed is attached toward the substrate 2. . This arc type evaporation source 14 is similar to that disclosed in, for example, Japanese Patent Application Laid-Open No. 63-18056, and has a conductive cathode 16 and a vacuum container 4 which also serves as an anode. The arc 16 discharges the cathode 16 locally to evaporate the cathode material 18. A DC arc discharge voltage is supplied between the cathode 16 and the vacuum container 4 from an arc power supply (not shown). The trigger electrode for starting the arc discharge and the like are not shown. The cathode 16 is made of, for example, a metal or a metal compound (alloy).

An arc type evaporation source 14 in the vacuum container 4
The electron beam evaporation source 20
Are provided toward the base material 2. The electron beam evaporation source 20 has a crucible 21 and heats an evaporation material 22 put therein by an electron beam to evaporate the evaporated material 24 to deposit the evaporated material 24 on the substrate 2 being conveyed. . The evaporation material 22 is made of, for example, a metal or a metal compound (alloy).

The inside of the vacuum container 4 has an anti-adhesion plate 26 for the purpose of preventing vaporized substances from reaching undesired locations.
It is properly divided by.

In the thin film forming apparatus, the transfer device 6
After the base material 2 is continuously conveyed by the arc type evaporation source 14, a metal thin film is formed as a base layer on the base material 2, and then a metal thin film is further formed by the electron beam type evaporation source 20. be able to.

In that case, the vaporized particles from the arc type vaporization source 14, that is, the cathode material 1 which is ejected from the cathode 16
No. 8 has a kinetic energy that is about one order of magnitude larger than the evaporating particles from the electron beam evaporation source or the sputtering evaporation source, for example, about several tens eV, so that the adhesiveness and the throwing power as the underlayer are A good thin metal film can be formed. The reason why the adhesion is good is that the kinetic energy of the evaporated particles is high and the reactivity with the base material 2 is increased. The reason why the adherence is good is that since the kinetic energy of the evaporated particles is high, the surface diffusion energy is large and the substrate 2
The particles that have reached the
This is because the migration effect makes it possible to roll even deeper in the concave portion and in the shadow of the convex portion.

As long as the underlayer is formed in this way, even the evaporated particles (that is, the evaporated material 24) of weak energy from the electron beam evaporation source 20 do not stop at the first arrival position. In addition, since it is possible to reach the back of the concave portion and the shadow of the convex portion, the evaporation material 24 from the electron beam evaporation source 20 is also covered with good coverage. This is because if a thin film having similar properties is present as the underlayer, the energy lost later at the location where the vaporized particles first arrive is reduced. In addition, the electron beam evaporation source 20
Even if the vaporized particles with weak energy from the electron beam evaporation source 2 can be adhered onto the thin film having similar properties as the underlayer, if it exists.
The evaporation material 24 from 0 is also coated with good adhesion. In either case, a thin underlayer is sufficient.

The energy lost by the later vaporized particles at the first arrival point is smaller when the underlayer and the vaporized particles that reach later are the same kind of substance than in the case of different kinds of substances. Further, the same kind of substance also has a higher strength with which evaporated particles that reach later adhere to the underlayer. Therefore,
The cathode material 18 evaporated from the arc evaporation source 14 and the evaporation material 24 evaporated from the electron beam evaporation source 20 are preferably the same kind of material, for example, the same kind of metal.

Moreover, since the electron beam evaporation source 20 can easily obtain a higher film formation rate than the arc evaporation source 14, if the electron beam evaporation source 20 is used, a high deposition rate can be obtained on the underlying layer. Thin films can be formed at a rate.
This is because, in general, in the case of an arc-type evaporation source, a large amount of energy is required to evaporate a large amount of cathode material from the cathode, and it is necessary to considerably increase the device configuration and power supply. This is because in the case of the electron beam evaporation source, it is possible to locally aim and heat only the inside of the crucible with the electron beam, and it is easy to locally heat the evaporation material to a high temperature.

As described above, in this thin film forming apparatus, by combining the arc evaporation source 14 and the electron beam evaporation source 20 having the above-mentioned characteristics, both characteristics can be utilized. That is, the arc evaporation source 14
The base layer 2 can be formed thin on the base material 2 with good adhesion and throwing power, and can be formed at a high speed by the electron beam evaporation source 20. The thin film after this can also be formed as described above. Since the presence of the underlayer improves the adhesion and throwing power, a thin film such as a metal is formed on the base material 2 having a large number of fine irregularities in a band shape as a whole with good adhesion and throwing power and high speed. Can be formed with. The fact that high-speed film formation is possible means that the productivity is excellent. Therefore, according to this thin film forming apparatus, it is possible to reduce the production cost (film forming cost).

Of course, one or both of the arc type evaporation source 14 and the electron beam type evaporation source 20 as described above may be provided in plural units.

A plurality of arc evaporation sources 14 and electron beam evaporation sources 20 as described above may be provided to form thin films on both front and back surfaces of the base material 2. An example is shown in FIG.

In the thin film forming apparatus shown in FIG. 2, two arc evaporation sources for depositing the cathode material 18 on the front surface and the back surface of the substrate 2 being conveyed are provided on two wall surfaces of the vacuum container 4 which face each other. 14a and 14b are attached toward the base material 2. Both arc type evaporation sources 14a, 14
b is the same as the arc evaporation source 14.

Further, in the vacuum container 4, vaporized substances 24 are vapor-deposited on the front surface and the back surface of the substrate 2 being conveyed, respectively 2
Attach the electron beam evaporation sources 20a and 20b of the base to the substrate 2
It is provided for. Both electron beam evaporation sources 20a, 2
0b is the same as the electron beam evaporation source 20. Electron beam evaporation source 20a for forming a film on the surface of the base material 2
Is provided on the lower side of the base material transport than the corresponding arc type evaporation source 14a, and the electron beam type evaporation source 20b that forms a film on the back surface of the base material 2 is a base material rather than the corresponding arc type evaporation source 14b. It is provided on the lower side of transportation. In both cases, the underlayer is formed by the arc evaporation sources 14a and 14b,
This is for further film formation by the electron beam evaporation sources 20a and 20b.

According to this thin film forming apparatus, it is possible to easily form a thin film of metal or the like on both the front and back surfaces of the base material 2 with good adhesion and throwing power and at a high speed.

It is needless to say that one or both of the above-mentioned arc type evaporation source and electron beam type evaporation source may be provided on each side of the substrate 2.

Further, in any of the embodiments shown in FIGS. 1 and 2, when the base material 2 is a conductive material, a negative bias voltage may be applied to it. The cathode material 18 from the evaporation sources 14, 14a, 14b contains a significant proportion of those ionized by the arc discharge, which can be accelerated towards the substrate 2 by this bias voltage. Further, the adhesiveness and the throwing power of the underlayer are further improved, and the adhesiveness and the throwing power of the entire thin film are further improved.

Further, in any of the embodiments shown in FIGS. 1 and 2, the gas is introduced into the vacuum container 4 via the gas inlet port 28.
A reactive gas 30 that reacts with the cathode material 18 and the evaporated material 24 may be introduced. Reactive gas 30
Is, for example, nitrogen gas, hydrocarbon gas, oxygen gas, or the like. By doing so, the cathode substance 18 and the vaporized substance 24 are combined with the reactive gas 30 in the vicinity of the surface of the base material 2, and the cathode substance 18 and the vaporized substance 24 are composed of, for example, a nitride, a carbide, an oxide or the like. A compound thin film can be formed on the substrate 2.

[0034]

EXAMPLE In the thin film forming apparatus shown in FIG. 1, the electron beam evaporation source 20 is of 5 kW output, the cathode 16 of the arc evaporation source 14 and the electron beam evaporation source 20.
As the evaporation material 22 of, Al (aluminum) having a purity of 3N was used. Further, as the base material 2, a polyurethane non-woven fabric having a width of 300 mm was used. 350 mm between the cathode 16 and the substrate 2, and 2 between the electron beam evaporation source 20 and the substrate 2.
It was set to 50 mm. The feeding speed of the base material 2 by the carrying device 6 was 100 mm / min.

Then, the inside of the vacuum container 4 is 5 × 10 ^-6 Tor.
After exhausting to about r, as an example, an Al thin film is formed to a thickness of 300 nm on the substrate 2 by the arc evaporation source 14 with an arc current of 70 A, and an electron beam output by the electron beam evaporation source 20 is further formed thereon. 2 Al thin films at 5 kW
A 700 nm thick film was formed to form an Al thin film having a total thickness of 3000 nm.

As a comparative example, the same film thickness was formed only by the arc evaporation source 14 and only by the electron beam evaporation source. Further, as a comparative example, the same film thickness was formed using the above-mentioned conventional sputtering evaporation source.

Adhesion of the Al thin film by each of these means,
Table 1 shows the measurement results of the throwing power and the film formation time. The adhesion was evaluated by observing the degree of peeling of the film after the bending test 100 times. The throwing power was evaluated by observing with a microscope whether or not the film was formed to the inner part of the recess.

[0038]

[Table 1]

As is clear from the results shown in Table 1, according to the apparatus of the example, a thin film excellent in adhesion and throwing power can be formed at a high speed.

[0040]

Since the present invention is formed as described above, it has the following effects.

According to the first aspect of the present invention, the advantage of the arc-type evaporation source being that the thin film has good adhesion and throwing power, and the electron-beam-type evaporation source is capable of high-speed film formation. Taking advantage of both of these advantages, it is possible to form a thin film of a metal or the like on a base material having a band-like shape and a large number of fine irregularities, with good adhesion and sticking property, and at high speed.

According to the second aspect of the present invention, a thin film of metal or the like is easily formed on both the front and back surfaces of a base material having a band-like shape and a large number of fine irregularities, with good adhesion and throwing power, and at a high speed. can do.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a thin film forming apparatus according to the present invention.

FIG. 2 is a sectional view showing another example of the thin film forming apparatus according to the present invention.

FIG. 3 is a partially enlarged plan view showing an example of a base material having a strip shape and a large number of fine irregularities.

FIG. 4 is a plan view showing, in an enlarged manner, another example of a base material having a strip shape and having a large number of fine irregularities.

[Explanation of symbols]

 2 Base Material 4 Vacuum Container 6 Transfer Device 14, 14a, 14b Arc Type Evaporation Source 18 Cathode Material 20, 20a, 20b Electron Beam Type Evaporation Source 24 Evaporation Material

Claims (2)

[Claims] 1. A vacuum container, a transfer device for transferring a strip-shaped substrate having a large number of fine irregularities in the vacuum container, and a vacuum container which is attached to the vacuum container to evaporate a cathode substance by vacuum arc discharge. And an arc type evaporation source for depositing it on the base material, and in the vacuum container, provided on the lower side of the base material conveyance than the arc type evaporation source, for evaporating the evaporation material by an electron beam. An electron beam evaporation source for depositing it on the substrate, a thin film forming apparatus. 2. A vacuum container, a transfer device for transferring a strip-shaped substrate having a large number of fine irregularities inside the vacuum container, and a vacuum container which is attached to the vacuum container to evaporate a cathode substance by vacuum arc discharge. First and second arc evaporation sources for respectively depositing it on the front surface and the back surface of the base material, and for evaporating an evaporation material by an electron beam to evaporate the evaporation material by the electron beam. A first electron beam evaporation source and a second electron beam evaporation source for vapor deposition on the front surface and the back surface of the substrate, respectively, and the first electron beam evaporation source is located on the lower side of the substrate transportation than the first arc evaporation source. The thin film forming apparatus is characterized in that the second electron beam evaporation source is provided on the lower side of the substrate transportation than the second arc evaporation source.