Vapor deposition apparatus having pretreatment device that uses plasma

Abstract

A roller-type continuous vapor deposition film-forming apparatus for a substrate that is to be conveyed at high speed, comprising a plasma pretreatment device and a film-forming apparatus provided in series, wherein a substrate conveying compartment 12A, a pretreatment compartment 12B and film formation compartment 12C are formed inside a chamber 3; and a substrate S is wound from an unwinding roller 13 onto a plasma pretreatment roller 20 and film formation roller 25, which are provided in series, via guide rollers 14a-14d, and is taken up by a take-up roller 15. In the pretreatment device, plasma P is supplied toward the substrate S inside a gap, wherein a plasma-forming gas to be supplied from plasma supply nozzles 22a, 22b is surrounded by the pretreatment roller, the plasma supply nozzles and a magnet 21, as magnetic forming means, and the plasma is electrically set to a positive electrical potential, power is supplied between the electrodes positioned on the substrate surface side, the plasma P is generated and an active pretreatment surface is formed on the surface of the substrate S. An inorganic oxide can be formed at high speed by the film formation device by physical vapor deposition or the like on a pretreatment surface of a substrate that has been subjected to the pretreatment.

Description

TECHNICAL FIELD[0001]The present invention relates to a multiple roller-type continuous vapor deposition film-forming apparatus (hereunder referred to as “film-forming apparatus”), provided with both a pretreatment roller for plasma pretreatment and a film-forming roller in series, that conveys a long substrate such as a film or sheet at high speed while continuously forming a thin-film on the substrate surface, and particularly it relates to a film-forming apparatus that stably and continuously forms a homogeneous thin-film with excellent adhesiveness on the surface of a long substrate under reduced pressure.BACKGROUND ART[0002]In the prior art there exist methods such as vacuum vapor deposition, sputtering, wet coating by gel-sol methods and the like, and thermal CVD, as means for continuously forming metal and metal oxide thin-films in chambers on conveyed substrates for long films or sheets of plastics or the like, and film-forming apparatuses are known that form films by sputte...

AI Technical Summary

Benefits of technology

[0052]The roll-type continuous vapor deposition film-forming apparatus of the invention has a pretreatment roller provided in a pressure reduction chamber, that performs at least plasma treatment of a taken-up substrate, as pretreatment of a substrate that has been carried out in the prior art, and plasma pretreatment means comprising plasma-supply means that supplies plasma gas comprising oxygen, nitrogen, carbon dioxide gas and ethylene, or a mixed gas of one or more of these with argon, and magnetic field-forming means, situated so as to concentrate the supplied plasma gas near the substrate surface in a concentrated manner, with an enclosing gap being formed, and by application of a prescribed voltage between the plasma pretreatment roller and plasma-supply means, it is possible to rapidly and stably form a homogeneous thin-film continuously on a long substrate with excellent adhesiveness on the substrate surface.

[0053]According to the invention, in the plasma pretreatment device there is situated plasma pretreatment means in such a manner that the supplied plasma mixed gas is concentrated near the substrate surface being conveyed on the pretreatment roller surface, with an enclosing gap being formed, and by conducting plasma pretreatment with a desired voltage actively applied between the substrate and the plasma-supply means, it is possible to control the plasma density of the pretreatment plasma as desired, to reliably and effectively implant the plasma onto the substrate surface during pretreatment, and physically or chemically modify the surface properties of the substrate, while helping to improve adhesiveness between the vapor deposited thin-film and substrate in the film formation step to allow continuous treatment, which as a result can reduce detachment of the vapor deposited thin-film.

[0054]Also, since the roller-type continuous vapor deposition film-forming apparatus of the invention is a roller-type continuous vapor deposition film-forming apparatus comprising a plasma pretreatment device as a roll-to-roll type with the pretreatment roll and forming roll installed in series, it is possible to accomplish continuous and stable conveyance from pretreatment to film formation, while the substrate can be conveyed at higher speed than the conventional conveying speed and film-forming treatment of the vapor deposition film can be accomplished at high speed, so that the film-forming speed can therefore be increased, i.e. productivity improved, while having a low plasma output.

[0055]According to the invention, plasma pretreatment is carried out by using plasma-supply means to supply plasma with increased reactivity that is argon plasma as an inert gas using a plasma-forming gas that does not form a film, and active gas plasma, and the reactive plasma is supplied into a limited gap formed by a pretreatment roll, plasma-supply means and magnetic field-forming means, to allow concentration of the plasma near the substrate surface, allowing effective activation of the substrate surface by pretreatment while allowing film-forming treatment of the vapor deposition film to be accomplished even when the substrate is conveyed at higher speed than the conventional conveying speed, and effectively making use of the activated surface to allow reinforcement of adhesiveness between the vapor deposition film and substrate surface.

[0056]Since the invention can also increase dense formation of the vapor deposition film and adhesiveness of the vapor deposition film, that is seen with reduced water vapor transmittance and higher laminated strength, this allows production at higher speed than in the prior art and allows continuous and stable production of a vapor deposition film with excellent adhesiveness and excellent barrier performance.

[0057]The invention further allows membrane stress to be reduced and damage to the substrate to be reduced (minimizing electrical charge-up, reducing substrate etching and reducing substrate coloration).

Problems solved by technology

In this type of known film-forming apparatus, the thin-film forming speed is not slow with vacuum vapor deposition, but the precision of the thin-film homogeneity is poor, and therefore the yield is notably poor.

Also, in sputtering, the precision of thin-film homogeneity is satisfactory but the thin-film forming rate is very low and productivity is poor.

In thermal CVD processes, a source gas is oxidized and decomposed by the heat energy of the substrate to form a thin-film, and they require the substrate to be at high temperature, such that when the substrate is a plastic film, decomposition and oxidation of the plastic film can occur, making it impossible to form a homogeneous thin-film on the plastic film substrate.

Furthermore, in known film-forming apparatuses, the thin-films formed on substrates cannot exhibit a sufficient barrier property, and adhesiveness between the thin-film and substrate is insufficient.

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