JPH11242102A - Antireflection film and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an antireflection film on the surface of a display, such as CRT or LCD, as easily as possible with high productivity. SOLUTION: The high-refractive index films 41 of the antireflection film 1 formed by successively laminating the high-refractive index films and low- refractive index films plural times are silicon nitride films and the low-refractive index films 42 are silicon oxide films. Both of the silicon nitride films and the silicon oxide films are formed by reactive sputtering using silicon as a target material and using gaseous nitrogen and gaseous oxygen respectively as reactive gases.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an antireflection film provided on the surface of a display such as a CRT or an LCD, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in a display such as a CRT, as a means for preventing reflection on the surface, a method of applying a multi-layer film composed of a high refractive index film and a low refractive index film to the surface by vacuum deposition or the like has been known. LCs that are being used and are becoming more widespread
In D (Liquid Crystal Display), in addition to the above technique, a technique of providing an uneven structure on the substrate surface and performing irregular reflection is used.

[0003]

As described above, in the prior art, titanium dioxide (refractive index n) is used as the high refractive index film.
= 2.4) and the like, and silicon dioxide (n =
1.5) at least two different refractive indices
More than one type of material is used.

[0004] In addition, although the film quality such as adhesion and uniformity of the film thickness is inferior to the film formed by the sputtering method in forming each film, the productivity based on the film formation rate is high. For this reason, the electron beam evaporation method is used.

An object of the present invention is to solve the above-mentioned problems and to provide a high-quality antireflection film formed by using one kind of material and further using a sputtering method.

[0006]

Means for Solving the Problems A first invention of the present invention is:
In an antireflection film formed by sequentially laminating a high-refractive-index film and a low-refractive-index film a plurality of times, the high-refractive-index film is made of silicon nitride (Si).
_{xN y} ; x ≦ 3, y ≦ 4 Refractive index n = 1.7 to 2.0)
Film and the low refractive index film is silicon oxide (SiO _x ; x)
≦ 2 Refractive index n = 1.4-1.5) An antireflection film characterized by being a film.

According to a second aspect of the present invention, in the first aspect, the silicon nitride film and the silicon oxide film are both reactive sputtering using silicon as a target material and nitrogen gas and oxygen gas as reactive gases, respectively. And a method for producing an antireflection film.

As described above, according to the present invention, since the high refractive index film is a silicon nitride film and the low refractive index film is a silicon oxide film, the target material may be only silicon.

In addition, since silicon as a metal is used as a target material, direct current (DC) reactive sputtering can be performed, and as a result, the film formation rate can be made closer to electron beam evaporation.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an explanatory sectional view showing an example of the configuration of the antireflection film of the present invention.

As shown in FIG. 1, reference numeral 1 denotes an antireflection film according to the present invention, and a high refractive index film 41 and a low refractive index film 4
2, a multilayer film 4 (four layers) composed of a high refractive index film 41 and a low refractive index film 42 is sequentially laminated to exhibit an antireflection property.

The base material 2 needs to have sufficient transparency, and furthermore, has to have a certain degree of rigidity and surface smoothness.

For example, polyester, polyolefin,
Polymer films such as polycarbonate, triacetylcellulose, polyacrylate, and polyethersulfone, glass, and the like are exemplified as suitable ones.

The protective layer can be provided as appropriate, and can be selected from many compositions depending on the intended use as long as it does not affect the function of the present invention. Examples thereof include polyolefin, polyvinyl chloride, and polyvinylidene chloride. And a transparent film such as polyvinyl alcohol.

The antireflection film of the present invention comprises a high refractive index film made of a silicon nitride film and a low refractive index film made of a silicon oxide film.
It can be formed by alternately laminating a specific film thickness a plurality of times.

Further, a water repellent layer 5 and a hard coat layer 3 may be provided.

The water-repellent layer 5 can be formed by any method as long as it does not affect the antireflection function, and can be selected according to the intended use. As an example, a CFC-based fluorosilane is used.
Forming by a method.

The hard coat layer 3 preferably has transparency to the extent that the whole transparency is not impaired, and has a refractive index similar to that of the substrate 2, and is preferably made of an ultraviolet curable acrylic resin or the like. As an example.

[0020]

EXAMPLES Examples of the present invention (an example of an antireflection film having a four-layer structure) will be described more specifically below. <Example 1> Glass was used as the base material 2, and the anti-reflection film was formed by first using silicon as a target material from the base material side.
A silicon nitride film as the high refractive index film 41 having a thickness of 70 nm was formed by direct current type reactive sputtering under nitrogen gas introduction.

Subsequently, a silicon oxide film as the low-refractive-index film 42 having a thickness of 70 nm was formed by direct current type reactive sputtering under the introduction of oxygen gas.

Further, a high refractive index film 41 is similarly formed thereon.
A silicon nitride film of 140 nm and a silicon oxide film of low refractive index film 42 were each formed to a thickness of 140 nm.

The reflectivity of the formed multilayer film 4 at 550 nm was 0.5%, and a uniform and high-quality antireflection film without reflection unevenness could be formed.

[0024]

According to the present invention, silicon is used as the base material of the antireflection film, silicon nitride film is used as the high refractive index film, silicon oxide film is used as the low refractive index film, and nitrogen gas and Since it can be formed by reactive sputtering under the introduction of oxygen gas, a high-quality antireflection film can be easily provided.

Further, by using silicon as a metal as a target, it is possible to form a film at a high rate by DC type reactive sputtering, thereby improving productivity.

[Brief description of the drawings]

FIG. 1 is a sectional view of an antireflection film according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 {Anti-reflection film 2} Base material 3} Hard coat layer 4} Multilayer film 41} High refractive index film, silicon nitride film 42} Low refractive index film, silicon oxide film 5} Water repellent layer

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI C23C 14/34 C23C 14/34 A G02B 1/10 H01J 9/20 A H01J 9/20 29/88 29/88 G02B 1/10 Z

Claims (2)

[Claims] An antireflection film formed by sequentially laminating a high refractive index film and a low refractive index film a plurality of times, wherein the high refractive index film is a silicon nitride film and the low refractive index film is a silicon oxide film. An antireflection film, which is a film. 2. The method according to claim 1, wherein the silicon nitride film and the silicon oxide film are both formed by reactive sputtering using silicon as a target material and using a nitrogen gas and an oxygen gas as reactive gases, respectively. A method for producing the antireflection film according to the above.