JP3416173B2 - Electron beam heating type vapor deposition apparatus and vapor deposition method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam heating type vapor deposition apparatus and vapor deposition method for vapor deposition forming a metal compound such as a metal oxide on the surface of a long film while it is running.

[0002]

2. Description of the Related Art The electron beam heating type vapor deposition method, in which a vapor deposition material is heated by an electron beam to form a thin film on a substrate, is easier to mass-evaporate a high melting point material than other vapor deposition methods. Since it is a method that can stably deposit a pure film,
In recent years, it has begun to be widely used for vapor deposition of metals, ceramics and the like onto resin films.

An electron beam heating type vapor deposition apparatus for a film generally has an electron beam generating mechanism for generating an electron beam, a vapor deposition material holding section for holding a vapor deposition material at an electron beam irradiation position, and this vapor deposition material holding section. On the other hand, a cooling drum which is provided so that a part of its outer peripheral surface faces each other and is rotationally driven by a driving machine, and a film running means for running the film while the film is wound around a part of the outer peripheral surface of the cooling drum. A partition wall disposed between the cooling drum and the vapor deposition material holding portion, having a vapor passage opening formed opposite to the vapor deposition region of the film winding portion of the cooling drum, and a vacuum container accommodating each of the above mechanisms. It is equipped with.

By the way, in recent years, TiO ₂ , SiO ₂ , ZrO ₂ , In ₂ O ₃ , SnO ₂ and Y _{2 are formed} on the film for the purpose of improving the corrosion resistance and gas impermeability of the film.
It is often practiced to deposit metal oxides such as O ₃ , metal nitrides, and metal fluorides. Two methods can be used to deposit such a metal compound using the above apparatus.

The first is a method of using the metal compound itself to be vapor-deposited as a vapor deposition material. However, the above-mentioned high-purity metal compound is generally extremely expensive and has a high melting point as compared with a single metal. However, the input energy was large, and there were problems such as radiant heat to the film and splash (generation of splashes) due to decomposition gas.

The second method is an improvement over the drawbacks of the first method, in which a metal forming a metal compound is used as a vapor deposition material, while a reactive gas to be combined with the metal is kept in a vacuum chamber at a constant level. It is introduced at a pressure of, for example, 1 × 10 ^{-2 to} 1 Pa. In this way, the metal vapor emitted from the vapor deposition material comes into contact with the reactive gas, bonds with the reactive gas, and then deposits on the film.

[0007]

However, in the method of reacting the second metal vapor with the reactive gas, the pressure of the reactive gas in the vacuum vessel is low and the reaction rate between the reactive gas and the metal vapor is small. Therefore, if the amount of metal vapor generated is increased, unreacted metal vapor may remain, and the metal compound may be vapor-deposited on the film in a state where the metal is mixed. Therefore, there is a problem that it is difficult to increase the production efficiency of the vapor deposition film.

It is also conceivable that the reactive gas introduced into the vacuum vessel is ionized in advance by discharge or electron beam irradiation to generate reactive gas ions and then reacted with the metal vapor, but in that case, There is a drawback that the device becomes complicated and the equipment cost increases significantly.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to improve the reaction efficiency between a metal vapor and a reactive gas without complicating the apparatus structure and improve the production efficiency of a vapor deposition film. .

[0010]

An electron beam heating type vapor deposition apparatus according to the present invention is provided with a nozzle that opens in a vacuum container and has a reactive gas introducing mechanism capable of introducing a reactive gas into the vacuum container from this nozzle. The nozzle is provided so that the gas flow ejected from the nozzle intersects a flow path of an electron beam reaching the vapor deposition material and then intersects a vapor flow flowing from the vapor deposition material to the film. And

On the other hand, according to the electron beam heating type vapor deposition method of the present invention, the film is run while being wound around a part of the outer peripheral surface of the cooling drum in the vacuum container.
The vapor deposition material facing the film winding portion is irradiated with an electron beam to generate metal vapor from the vapor deposition material, and a reactive gas is emitted from the nozzle disposed in the vacuum container.
Introduced at a pressure of × 10 ^{-2 to 1} Pa and intersecting the reactive gas flow with the electron beam flow path to the vapor deposition material, the reactive gas is further flowed from the vapor deposition material to the film. And a reactive gas are reacted with each other to form a metal compound film on the film surface.

[0012]

In the electron beam heating type vapor deposition apparatus and vapor deposition method according to the present invention, the reactive gas released from the nozzle into the vacuum chamber first comes into contact with the electron beam for heating the vapor deposition material and is ionized to have high activity. This produces reactive gas ions. The electron beam for heating the vapor deposition material has a high output, and its irradiation width is set according to the width dimension of the film, so even if reactive gas is supplied corresponding to the entire width of the film, the reactive gas Can be efficiently and uniformly ionized. Reactive gas ions generated by ionization have a high activity for metal vapor, and when they are brought into contact with metal vapor, they are immediately bound to the metal vapor and the produced metal compound vapor is vapor-deposited on the film surface to form a uniform metal compound film. It is formed.

The reactive gas introduction pressure is 1 × 10 ^-2.
If it is less than Pa, sufficient reaction efficiency cannot be obtained, and if it is higher than 1 Pa, the mean free path of vapor generated from the vapor deposition material is shortened due to the introduced gas, and a dense vapor deposition film cannot be formed.

[0014]

1 is a schematic view showing an embodiment of an electron beam heating type vapor deposition apparatus according to the present invention. Reference numeral 1 in the figure is a vacuum container, and the inside pressure is reduced by a vacuum pump (not shown). A cylindrical cooling drum 2 made of metal or the like is arranged in the center of the inside of the vacuum container 1, and is rotationally driven by a driving device (not shown).

A long film F is wound around a part of the outer peripheral surface of the cooling drum 2 in the circumferential direction of the drum, and is continuously run between the uncoiler 3 and the chiller 4. A vapor deposition material holding portion 6 is arranged so as to face the film winding portion of the cooling drum 2, and a metal vapor deposition material 8 constituting a metal compound to be vapor deposited is accommodated inside the vapor deposition material holding portion 6. The vapor deposition material 8 is not necessarily a metal simple substance, and may be an alloy or a part thereof may already be compounded.

An electron beam generating mechanism (not shown) such as an electron gun is arranged on the side of the vapor deposition material holder 6, and the electron beam 12 is generated from this electron beam generating mechanism. The electron beam 12 is bent by the magnetic field generated by the magnetic field generation mechanism 10 installed on the opposite side of the vapor deposition material holding unit 6 and irradiated on the vapor deposition material 8, and the electron beam 12 causes the vapor deposition material 8 to be irradiated.
Is heated and its steam 14 is radiated toward the cooling drum 2.

If the vapor deposition film to be formed has a large width, a scanning mechanism for scanning the electron beam generating mechanism in the width direction of the film F may be provided. Further, the electron beam generating mechanism is not limited to the illustrated position, and the installation position may be arbitrarily changed as long as the electron beam 12 can be appropriately bent by the magnetic field to irradiate the vapor deposition material 8.

A partition wall 16 is provided between the cooling drum 2 and the vapor deposition material holder 6 to regulate the vapor deposition range. The partition wall 16 has a semi-cylindrical portion 16A for accommodating the cooling drum 2, and a constant space is provided between the inner peripheral surface of the semi-cylindrical portion 16A and the outer peripheral surface of the film winding portion of the cooling drum 2. A gap is formed. In the semi-cylindrical portion 16A, a rectangular vapor passage opening 18 is formed in a position facing the vapor deposition material holding portion 6 in the axial direction of the cooling drum 2. The vapor passage port 18 has the same overall length as the vapor deposition width of the film F.

On the same side as the electron beam generating mechanism,
A nozzle 20 of a gas introduction mechanism (not shown) is arranged, and the reactive gas is introduced into the vacuum container 1 from the nozzle 20. The nozzle 20 may eject gas in a strip shape having a width about the vapor deposition width of the film F, or may have a plurality of ejection openings arranged in a line in the width direction of the film F, and from these ejection openings. The gas may be jetted all at once. As the reactive gas, Ar, N
e, Kr, Xe, He, H 2, N 2, O 2, 1 or more kinds of gas selected from F ₂ can be used.

Reactive gas 22 emitted from nozzle 20
Has a path set so that it first intersects the path of the electron beam 12 and then intersects the path of the metal vapor 14 emitted from the vapor deposition material 8 (see FIG. 2). By setting the path in this manner, at least a part of the reactive gas 22 is ionized by the electron beam 12, and the reactive gas 22 comes into contact with the metal vapor 14 and is bonded to the metal vapor 14.

Next, a vapor deposition method using the above apparatus will be described. While depressurizing the inside of the vacuum container 1, the reactive gas 22 is jetted from the nozzle 20 at a constant flow rate so that the pressure inside the vacuum container 1 is 1 × 10 ⁻² to 1 Pa, more preferably 5 × 10 ^{−2 to} 5 ×.
Equilibrate at 10 ^-1 Pa. Equilibrium pressure in the vacuum vessel 1 is 1
If it is less than × 10 ^-2 Pa, the reactive gas ion concentration becomes dilute and the reaction efficiency becomes insufficient. If it is higher than 1 Pa, the metal vapor 14 generated from the vapor deposition material 8 has a short mean free path due to the gas molecules 22. , A dense vapor deposition film cannot be formed.

On the other hand, the electron beam generating mechanism and the magnetic field generating mechanism 10 are operated to irradiate the vapor deposition material 8 with the electron beam 12 to heat it, and vapor 14 is continuously generated from the vapor deposition material 8. And film F
Run.

Then, the reactive gas 22 ejected from the nozzle 20 is first contacted with the electron beam 12 and ionized to form a gas flow containing the reactive gas ions, and the vapor deposition material 8 is also added.
It comes into contact with the metal vapor 14 emitted radially from the. Since the reactive gas ions have high activity and are highly reactive, they are immediately combined with the metal vapor 14 in contact therewith, and the metal vapor 14 becomes a vapor of a metal compound and is deposited on the film F.

As described above, in this electron beam heating type vapor deposition apparatus and method, the reactive gas ejected from the nozzle is first contacted with the electron beam 12 for heating the vapor deposition material to generate highly active reactive gas ions. In addition, since the reactive gas ions are brought into contact with the metal vapor 14, even if the introduction pressure of the reactive gas 22 is low, the reaction efficiency between the metal vapor 14 and the reactive gas is high, and a uniform metal compound film is formed. The processing efficiency of the film F can be improved.

Further, since the electron beam 12 for heating the vapor deposition material has a high output and its irradiation width is set in accordance with the width dimension of the film F, the reactive gas 22 corresponds to the entire width of the film F. This reactive gas 2
2 can be efficiently and uniformly ionized, and
The configuration of the device is simple.

The present invention is not limited to the above-mentioned embodiments, and new constitutions may be added as necessary. For example, when the electron beam generating mechanism is scanned in the width direction of the film F, the nozzle 20 of the gas supply mechanism is also scanned following the electron beam generating mechanism so that the reactive gas 22 always intersects with the electron beam 12. The ionization efficiency may be increased. Further, a configuration in which the electron beam generating mechanism and the reactive gas ejection nozzle are integrated is also possible.

[0027]

[Experimental Example] Next, the effect of the present invention will be demonstrated with reference to an experimental example. The electron beam heating type vapor deposition apparatus shown in FIG. 1 was produced, the positions of the reactive gas ejection nozzles were changed to five ways as shown in FIG. 2, vapor deposition films were produced, and the quality of the vapor deposition film was compared. That is, in the experimental example, the oxygen gas 22 was ejected from the illustrated nozzle 20 as the reactive gas, and the oxygen beam 22 was crossed first with the electron beam 12 and then with the metal vapor 14.

On the other hand, in Comparative Examples 1 to 4, the nozzle 2
From the nozzle 30 installed on the side opposite to 0, the oxygen gas 22 was ejected in each of the directions a to d in the drawing. That is, a is a direction toward the vapor passage port 18, b is a direction orthogonal to the metal vapor 14, c is a direction first intersecting with the metal vapor 14 and then the electron beam 12, and d is a direction toward the vapor deposition material 8. is there.

In each case, the experimental conditions were unified as follows. Film F: thickness 25 μm, width 500 mm, PET vapor deposition material 8: Ti vapor deposition film thickness: 1000 Å oxygen introduction pressure: 1 × 10 ⁻¹ Pa electron beam generating mechanism: electron impact cathode type self-accelerating electron gun (90 ° Deflection) Acceleration voltage: 30 kV Emission current: 2 A Scan width of electron gun: 500 mm Distance between vapor deposition material holder 6 and film F: 250 mm Outer diameter of cooling drum 2: 400 mm Travel speed of film F: 10 m / min

On the other hand, as a conventional example, while the oxygen gas is simply introduced into the vacuum container 1 at a pressure of 1 × 10 ^-1 Pa, the traveling speed of the film F is 2 m / min and the emission current is 1.
Instead of 2 A, vapor deposition was performed under the same conditions as above. The reason why the traveling speed and the emission current are decreased is that, in this case, if these values are increased, the Ti vapor is not sufficiently oxidized.

Next, the reflectance (%) and the transmittance (%) at a wavelength of 550 nm were measured for each of the obtained six kinds of vapor-deposited films by using a self-recording spectrophotometer. Metal Ti
Absorbs light of 550 nm, the metal Ti
If is left, the sum of reflectance and transmittance does not reach 100%. The results are shown in Table 1. The nozzle position is represented by the nozzle code and the ejection direction in FIG.

[0032]

[Table 1]

As is clear from the above table, in the experimental example, Ti
The oxidation efficiency was good, and a vapor-deposited film made of high-purity TiO ₂ could be formed. In addition, the processing efficiency of the film is five times that of the conventional example. On the other hand, in each of Comparative Examples 1 to 4 in which the nozzle orientation is different, the oxidation efficiency is lower than that in the experimental example, and metal Ti remains in the deposited film, so that the performance as a TiO ₂ film cannot be obtained. It is clear.

[0034]

As described above, according to the electron beam heating type vapor deposition apparatus and vapor deposition method according to the present invention, the reactive gas ejected from the nozzle is first contacted with the electron beam for heating the vapor deposition material to increase the temperature. Since active reactive gas ions are generated and the reactive gas ions are contacted with the metal vapor, even if the reactive gas supply pressure is low, the reaction efficiency of the metal vapor is sufficiently enhanced and a uniform metal compound is obtained. A film can be formed and the processing efficiency of the film can be improved.

Further, since the electron beam for heating the vapor deposition material has a high output and its irradiation width is set corresponding to the width dimension of the film, it is assumed that the reactive gas is supplied corresponding to the entire width of the film. In addition, the reactive gas can be efficiently and uniformly ionized, and the configuration of the device can be simple.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of an electron beam heating type vapor deposition device according to the present invention.

FIG. 2 is a cross-sectional view of essential parts showing devices of an experimental example and a comparative example.

[Explanation of symbols] F film 1 vacuum container 2 cooling drum 3 Uncoiler (Film traveling means) 4 Recoiler (Film traveling means) 6 Vapor deposition material holder 8 evaporation materials 12 electron beam 14 Metal vapor 16 partitions 18 Steam passage port 20 nozzles 22 Reactive gas flow 30 Nozzle of Comparative Example

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-59-213033 (JP, A) JP-A-62-103851 (JP, A) JP-A-58-134414 (JP, A) JP-A-49- 52186 (JP, A) JP-A-52-47582 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C23C 14 / 00-14 / 58

Claims (2)

(57) [Claims] 1. An electron beam generating mechanism for generating an electron beam, a vapor deposition material holding portion for holding a vapor deposition material at the electron beam irradiation position, and a part of an outer peripheral surface facing the vapor deposition material holding portion. A cooling drum provided with a cooling drum that is driven to rotate by a driving machine, a film running unit that runs the film while the film is wound around a part of the outer peripheral surface of the cooling drum, and a vacuum container that houses each of the above mechanisms. In the electron beam heating type vapor deposition apparatus comprising: a nozzle that opens in the vacuum container for the vapor deposition material.
And a gas introduction mechanism that is provided on the same side as the electron beam generation mechanism and that can introduce a reactive gas from this nozzle into the vacuum container, and the nozzle has a flow path of the reactive gas ejected from the nozzle. An electron beam heating-type vapor deposition device, characterized in that it intersects with a flow path of the electron beam reaching the vapor deposition material, and then intersects with a vapor flow emitted from the vapor deposition material. 2. A vapor deposition material, which is arranged to face a film winding portion, is irradiated with an electron beam while the film is running in a vacuum container while the film is wound around a part of an outer peripheral surface of a cooling drum. together to generate a metal vapor from the material, the relative Oite the deposition material in a vacuum chamber
A reactive gas is introduced at a pressure of 1 × 10 −2 to 1 Pa from a nozzle arranged on the same side as the electron beam irradiation source, and this reactive gas flow is made to intersect the flow path of the electron beam reaching the vapor deposition material. After that, the reactive gas is further crossed with a vapor flow from the vapor deposition material toward the film to combine the metal vapor with the reactive gas ions to form a metal compound film on the film surface. Electron beam heating type vapor deposition method.