JPH0952733A - Functional article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably produce a large area of a function film by a direct current sputtering method and to improve durability and reliability for long term of the functional film by forming an overcoat layer consisting of a functional thin film layer and a specified metal (oxide) nitride on a base body. SOLUTION: An undercoat layer 3 consisting of the (oxide) nitride containing at least one kind of metal selected from among Zr, Ti, Sn, Ta and Nb at need and Si in (20:80) to (95:5) by an atomic percent and having >=1nm thickness is provided on the base body 4. The functional thin film layer 1 consisting of an oxide of at least one kind of metal selected from among In, Sn, Zn, Mo, W and Ti and the overcoat layer 2 consisting of the metal (oxide) nitride containing at least one kind of metal selected from among Zr, Ti, Sn, Ta and Nb and Si in (20:80) to (95:5) by the atomic percent and having >=4nm thickness are formed on the undercoat layer 3.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a functional article.

[0002]

_2. Description of the Related Art Conventionally, as protective films for functional coats such as transparent conductive films and radio wave transmission type heat ray blocking films, SiO ₂ , ZrSi _x O
_y , SnSi _x O _y , SiN _{x and the} like are known. These protective coat films have excellent performance of preventing the functional coat from being deteriorated by moisture and oxygen in the environment during use at high temperature, and further have excellent durability against mechanical abrasion and chemicals.

SiO ₂ is particularly often used as an alkali diffusion barrier film for a liquid crystal display substrate, because when it is coated on soda lime glass, the elution of alkali components in the glass can be effectively blocked. Since SiO ₂ is also excellent in mechanical or chemical durability, it has been studied for practical use for use as a protective film layer of various functional thin films. However, when attempting to form a film by a DC sputtering method, which is suitable for high-speed film formation on a large-area substrate, arcing frequently occurs due to the insulating oxide film formed on the target surface during film formation, resulting in stable operation. It was virtually impossible to continue film formation.

A high frequency sputtering method or a thin film forming method is used.
There are only CVD method (Chemical Vapor Deposition method) and vacuum evaporation method, and there are restrictions such as power output, film formation speed, film thickness uniformity and high temperature heating of the substrate. It was not possible to apply to applications that require a large area such as electric heating glass.

Further, ZrSi _x O _y and SnSi _x O _y have good characteristics as a protective film and can be manufactured by the DC sputtering method. However, when trying to form a film continuously for a long time, arcing often occurs due to the insulating oxide film deposited on the surface of the target and the surroundings, and the protection circuit operates during film formation to stop the sputtering power supply. However, there are problems such as occurrence of pinhole-like defects in the product.

As for SiN _x , although there is no problem in a small to medium-sized DC sputtering apparatus with a substrate size of up to about 30 cm square, when it is attempted to be manufactured with a film forming apparatus larger than that, arcing starts and some arcing suppression is suppressed. There is a problem that stable and continuous film formation cannot be performed for a long time unless measures are taken.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a functional article excellent in durability and long-term reliability, which can be stably manufactured in a large area by the DC sputtering method. And

[0008]

The present invention provides a functional article in which a functional thin film layer and an overcoat layer made of a metal nitride or an oxynitride are sequentially formed on a substrate. Provided is a functional article, wherein the substance or oxynitride is a nitride or oxynitride of Si and at least one selected from the group consisting of Zr, Ti, Sn, Ta and Nb.

In the present invention, an undercoat layer made of metal nitride or oxynitride is formed between the substrate and the functional thin film layer, and the metal nitride or oxynitride is
A nitride or an oxynitride of at least one selected from the group consisting of Zr, Ti, Sn, Ta and Nb and Si is preferable.

In the present invention, it is preferable to have an overcoat layer and an undercoat layer. With such a configuration, diffusion of oxygen and moisture from the front surface side and the substrate side can be suppressed. Also, by using the same material for the overcoat layer and the undercoat layer,
Films can be formed from the same target, and as a result, the number of targets made of the same material can be increased, so that productivity can be improved.

The metal nitride or oxynitride as the overcoat layer and / or the undercoat layer is
Since it has excellent shielding performance against oxygen permeation,
Particularly preferred is a Zr nitride.

The composition ratio of Si and Zr may be 20:80 to 95: 5 in terms of the atomic ratio of Si to Zr. Particularly, from the viewpoint of transparency of the film, 50:50 to 95: 5. : 5 is preferred. From the viewpoint of manufacturing stability by DC sputtering, 20:80 to 90: 1.
0 is preferable. Furthermore, from the simplicity of target manufacturing,
67:33 is preferable.

In the nitride film, it is sufficient that the film is transparent in the visible light region, and the nitride may not be bonded in the stoichiometrically most general ratio. The amount is preferably no more than 5% below the stoichiometric amount of atoms.

The thickness of the overcoat layer depends on the amounts of water and oxygen that pass through the overcoat layer and diffuse inside during use. For example, heating during the production of laminated glass for automobiles, and refrigeration / frozen showcases. Considering the situation of use as the anti-fog window of 4 nm, 4 nm, particularly 8 nm or more is preferable.

The undercoat layer has a thickness of 1 nm, particularly 2 nm, in order to prevent diffusion of adsorbed moisture from a glass substrate or alkali of glass components or diffusion of stored moisture from a plastic substrate such as polycarbonate.
The above is preferable.

In the present invention, a part of the overcoat layer and / or the undercoat layer is 1) adjusted to the optimum film thickness by optical design, 2) shortening the film formation tact time, 3) reducing the target material cost, etc. From this point of view, other film materials that can be formed at high speed and have low film formation cost, for example, ZnO and SnO _{2 formed} by reactive sputtering from a target of metal Zn or metal Sn.
It can also be. That is, the overcoat layer is formed by forming a nitride of Si and Zr with a certain thickness and then forming the remaining necessary thickness with SnO ₂ .

FIG. 1 is a sectional view of an example of the functional article of the present invention. In the figure, 1 is a functional thin film layer, 2 is an overcoat layer, 3 is an undercoat layer, and 4 is a substrate.

The substrate is not particularly limited, and a glass substrate or the like is used.

The functional thin film layer is not particularly limited, and examples thereof include a transparent conductive film mainly containing an oxide of at least one metal selected from the group consisting of In, Sn and Zn.

Specific examples thereof include oxides of In and Sn, ZnO 2 doped with Ga or Al, and SnO ₂ doped with F or Sb. In the case of Ga-doped ZnO, it is preferable that Si is further doped.

In any of the above transparent conductive films, oxygen deficiency is greatly involved in electrical conduction, and in particular, excessive infiltration of oxygen into the film causes the conductive carriers to disappear and the electrical conductivity to be greatly deteriorated. , A suitable protective film is needed.

Further, the functional thin film layer is an oxide film of at least one metal selected from the group consisting of Mo, W and Ti, which is stoichiometrically deficient in oxygen and has optical absorption in the near infrared region. An oxide film or the like having the above can also be mentioned.

Specific examples thereof include MoO _x , WO _3-x , TiO _2-x, etc. These oxide films are in the state of a transparent film which is sufficiently oxidized and has a small amount of oxygen and is not oxidized. Excellent heat ray blocking ability in the middle area with a sufficient metallic opaque film,
It has a blue absorption color, but even after the film is formed, the film becomes transparent due to oxidation and reduction from the atmosphere during use,
Since absorption increases and transmittance decreases, an appropriate protective film is still necessary for long-term reliability.

In addition, as the functional thin film layer, Ag, Ag-Pd
Examples thereof include Ag alloys.

In the present invention, it is selected from the group consisting of Ti, Zr, Hf and Cr between the overcoat layer and the functional thin film layer and / or between the functional thin film layer and the undercoat layer. Metal nitrides or oxynitrides can be formed. Since these metal nitrides or oxynitrides are crystalline and have a columnar crystal structure, the diffusion barrier effect as described above is small, but they themselves react with moisture and oxygen, resulting in Prevents deterioration of the thin film layer.

[0026]

In general, an oxide film formed on a non-heated substrate by a so-called vacuum film forming method such as a sputtering method or a vacuum vapor deposition method is
It has a columnar crystal structure. The grain boundary portion of such a columnar crystal structure is structurally sparse, and molecules causing deterioration such as moisture and oxygen in the atmosphere can pass through this relatively easily. Therefore, such a film cannot be said to be suitable as a protective film that blocks moisture and oxygen.

On the other hand, the nitride or oxynitride film of Si and at least one selected from the group consisting of Zr, Ti, Sn, Ta and Nb is amorphous and uniformly grows on the substrate. Therefore, a clear columnar crystal structure is not taken.

That is, the nitride or oxynitride film of Si and at least one selected from the group consisting of Zr, Ti, Sn, Ta and Nb in the present invention does not have structurally sparse grain boundaries. Further, since the material forming the film is a nitride or an oxynitride, compared to an oxide film or the like, there are few adsorption sites for moisture and oxygen even in the crystal grains, and the diffusion speed is slow. For the above reasons, the protective film is excellent in the ability to prevent factors such as water, oxygen, and alkaline components that cause deterioration from entering through the film from the outside.

Further, a nitride or oxynitride film of Si and at least one selected from the group consisting of Zr, Ti, Sn, Ta and Nb is a direct current suitable for high speed film formation on a large area substrate. Since abnormal discharge such as arcing and unstable discharge do not occur during manufacturing by the sputtering method, problems such as insufficient thickness of the protective film due to discharge stoppage and pinhole generation due to arcing do not occur. Therefore, using this as a protective film layer brings not only excellent long-term reliability as a functional article, but also the advantage that stable production is possible.

[0030]

【Example】

[Example 1] A soda is used as a substrate in an in-line type sputtering film forming apparatus that has a load lock chamber, and can transport a substrate in the film forming chamber and reciprocate it to coat a large number of substrates without breaking the vacuum. I set a lime glass.

Next, 5% by weight of Ga ₂ O ₃ and 0.1% by weight of SiO ₂
% Target using ZnO added 3% To
A ZnO 3 -based transparent conductive film was formed to a thickness of 120 nm by DC sputtering in an Ar gas atmosphere of rr, and subsequently a Si-Zr alloy target (target composition: 66.7 atomic% Si and 33 .3 atomic% Zr) was used to form a 20 nm-thick ZrSi _x N _y film as an overcoat film by the same DC sputtering method in an Ar / N ₂ mixed gas atmosphere of ₃ mTorr.

When forming the ZnO-based transparent conductive film and the ZrSi _x N _y film, there was no abnormal discharge such as arcing, and it could be carried out extremely stably.

The resulting laminate had a visible light transmittance of 84%,
It had a sheet resistance of 160Ω / □ and good transparency and conductivity. When this was placed in a thermo-hygrostat at 40 ° C. and a relative humidity of 90% and evaluated for durability, visible light transmittance did not change after exposure for 30 days, and sheet resistance was 161 Ω / □. There was no change.

High temperature exposure test (atmosphere of 110 ° C.)
After 30 days, the sheet resistance is 164Ω / □,
It was an increase of 2.5%.

Example 2 In Example 1, before forming the ZnO-based transparent conductive film, a ZrSi _x N _y film having a film thickness of 10 nm was used as an undercoat film under the same conditions as those in Example 1. In the same manner as in Example 1 except that the layers were formed, three films were formed on the soda lime glass substrate to obtain a laminated body. Regarding the stability of film formation, as in Example 1, it was extremely stable and had no problem.

The resulting laminate had a visible light transmittance of 83% and a sheet resistance of 158 Ω / □, and had both good transparency and conductivity.

In the same manner as in Example 1, the durability was evaluated by a constant temperature and constant humidity test and a high temperature exposure test. For constant temperature and humidity test,
The visible light transmittance and the sheet resistance did not change even after the exposure for 30 days, and in the high temperature exposure test, the sheet resistance after 30 days was 159 Ω / □, which was almost unchanged.

[Third Embodiment] In the second embodiment, the undercoat film and the overcoat film each have a film thickness of 30.
and nm of ZrSi _x N _y film and the film thickness 30 nm ZrSi _x N _y film, except that the functional thin film was MoO _x film having a film thickness of 40nm was obtained a laminate in the same manner as in Example 2. However, the MoO _x film was formed by sputtering in a CO ₂ -containing atmosphere using a target containing Mo as a main component.

Regarding the stability of film formation, as in Example 2, it was extremely stable and had no problem.

The resulting laminate had a visible light transmittance of 72%,
The heat ray transmittance was 48%, the sheet resistance was 23 kΩ / □, and both excellent heat ray blocking performance and radio wave transmission performance were provided.

When the durability was evaluated in the constant temperature and constant humidity test and the high temperature exposure test in the same manner as in Example 2, neither visible light transmittance nor sheet resistance changed after exposure for 30 days.

[Comparative Example 1] In Example 1, the thickness of the ZnO-based transparent conductive film was set to 150 nm, and the ZrSi film having a thickness of 20 nm was used.
_On a soda lime glass substrate, in the same manner as in Example 1 except that the ZrSi _x O _y film having a film thickness of 20 nm was used instead of the _x N _y film.
Two films were formed to obtain a laminate. Incidentally, ZrSi _x O _y film, Si-Zr alloy target (the target composition 66.7
Of Si and 33.3 at.% Of Zr) was formed by DC sputtering under an atmosphere of ₃ mTorr of Ar / O.sub.2 mixed gas.

[Comparative Example 2] In Comparative Example 1, the film thickness is 20.
A laminated body was obtained in the same manner as in Comparative Example 1 except that a SnSi _x O _y film having a thickness of 20 nm was used instead of the ZrSi _x O _y film having a thickness of 20 nm. In addition,
The SnSi _x O _y film is formed by a DC sputtering method using a Si-Sn alloy target (target composition is 80 atomic% Si and 20 atomic% Sn) in an atmosphere of ₃ mTorr Ar / O ₂ mixed gas. Formed.

[Comparative Example 3] In Comparative Example 1, the film thickness was 20.
A laminated body was obtained in the same manner as in Comparative Example 1 except that a SnO ₂ film having a thickness of 20 nm was used instead of the ZrSi _x O _y film having a thickness of 20 nm. Note that SnO ₂
The film was formed by a DC sputtering method using a Sn target in an Ar / O ₂ mixed gas atmosphere of ₃ mTorr.

[Comparative Example 4] In Comparative Example 1, the film thickness was 20.
A laminated body was obtained in the same manner as in Comparative Example 1 except that the SiO ₂ film having a thickness of 20 nm was used instead of the ZrSi _x O _y film having a thickness of 20 nm. Note that SiO ₂
The film was formed by a DC sputtering method using a Si target in an atmosphere of an Ar / O ₂ mixed gas of ₃ mTorr.

[Comparative Example 5] In Comparative Example 1, the film thickness was 20.
A laminated body was obtained in the same manner as in Comparative Example 1 except that a SiN _x film having a thickness of 20 nm was used instead of the ZrSi _x O _y film having a thickness of 20 nm. In addition, SiN _x
The film was formed by a direct current sputtering method in a 3 mTorr Ar / N ₂ mixed gas atmosphere using a Si target.

In each of Comparative Examples 1 to 4, before forming each overcoat film, pre-sputtering was performed for a sufficiently long time before the oxide film on the target surface was removed with pure Ar gas before the film formation.

When the SiO ₂ film of Comparative Example 4 was used, SiO ₂
When the film was formed, severe arcing frequently occurred on the target surface, and the protective circuit of the sputtering power source frequently stopped the film, so that the film could not be continuously formed.

In Comparative Examples 1 and 2, arcing did not occur immediately after the start of film formation, and a laminated film could be stably formed, but in the case of the ZrSi _x O _y film of Comparative Example 1, 3 from the start of film formation. In the case of the SnSi _x O _y film of Comparative Example 2, small arcing started to occur 7 hours after the start of film formation, and then the frequency of occurrence increased with the lapse of time, and after several hours, the sputtering was started. It was impossible to continue film formation because large arcing which activated the protection circuit of the power supply started frequently.

A constant temperature and humidity test and a high temperature exposure test were carried out in the same manner as in Example 1 except for Comparative Example 4 in which the film could not be formed because the discharge was unstable during the formation of the SiO ₂ film, and the change in the sheet resistance was measured. did. The results are shown in Table 1.

[0051]

[Table 1]

[0052]

EFFECTS OF THE INVENTION The functional article of the present invention has excellent durability in which the initial characteristics do not change even when used at high temperature for a long period of time. Further, it is possible to continuously and continuously produce a large area over a long period of time by the DC sputtering method without trouble such as abnormal discharge.

[Brief description of drawings]

FIG. 1 is a sectional view of an example of a functional article of the present invention.

[Explanation of symbols]

 1: Functional thin film layer 2: Overcoat layer 3: Undercoat layer 4: Substrate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuaki Aikawa 426-1, Ozawa Uehara, Kakuda, Aikawa-cho, Aiko-gun, Kanagawa Prefecture Asahi Glass Co., Ltd. Sagami Plant (72) Inventor, Kazura Ozawa Uehara, Kakuda, Aikawa-cho, Kanagawa 426 1 Asahi Glass Co., Ltd. Sagami Works

Claims (5)

[Claims] 1. A functional article in which a functional thin film layer and a metal nitride or oxynitride overcoat layer are sequentially formed on a substrate, wherein the metal nitride or oxynitride is A functional article which is a nitride or oxynitride of at least one selected from the group consisting of Zr, Ti, Sn, Ta and Nb and Si. 2. An undercoat layer made of a metal nitride or an oxynitride is formed between the substrate and the functional thin film layer, and the metal nitride or the oxynitride as the undercoat layer is formed. The functional article according to claim 1, which is a nitride or an oxynitride of Si and at least one selected from the group consisting of Zr, Ti, Sn, Ta, and Nb. 3. The functional article according to claim 1 or 2, wherein the metal nitride is a nitride of Si and Zr. 4. The functional thin film layer is a transparent conductive film containing an oxide of at least one metal selected from the group consisting of In, Sn and Zn as a main component.
[3] The functional article according to any one of [3]. 5. The functional thin film layer is an oxide film of at least one kind of metal selected from the group consisting of Mo, W and Ti, and is stoichiometrically deficient in oxygen to cause optical absorption in the near infrared region. The functional article according to any one of claims 1 to 3, which is an oxide film having