JPS60187671A - Formation of laminated film by reactive sputtering method - Google Patents

Abstract

PURPOSE:To form continuously a laminated film consisting of a TiO2 layer and a TiN layer on a substrate by disposing plural metallic Ti targets in the same vacuum vessel and effective reactive sputtering in an atmosphere of a gaseous mixture composed of Ar, O2 and N2. CONSTITUTION:The 1st metallic Ti target 3 and the 2nd Ti target 4 are juxtaposed in a vacuum vessel 2 and an atmosphere of a gaseous mixture composed of Ar, O2 and N2 is maintained in the vacuum 2. A substrate 5 is conveyed at a constant speed or is stopped at the points of the respective targets 3, 4 to execute reactive sputtering. If a low voltage is impressed to, for example, the target 3 and a high voltage to the target 4 in this stage, a TiO2 layer is formed on the substrate 5 by the reactive sputtering with gaseous O2 at the point of the target 3. A TiN layer is laminated thereon by the reactive sputtering with gaseous N2 at the point of the target 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a lamination solution 11 of a titanium oxide layer and a titanium nitride layer on a substrate! The present invention relates to a method for continuously forming a film at a low cost.

In recent years, from the viewpoint of energy conservation, window glasses of buildings and other structures have been required to have high heat-insulating properties. Metal films are suitable in terms of heat ray reflectivity, but among them, they transmit a suitable amount of visible light, and their ability to reflect light at wavelengths longer than near-infrared rays is higher than other metals! A thin layer of metal 11 is useful. However, because these single-layer films of precious metals do not have sufficient adhesion to the substrate and have low chemical durability, glass plates coated with these films cannot be used as intermediate plates. I can't. Therefore, when such a glass plate with a precious metal film is used, a glass plate with the noble metal film attached on the inside is opposed to an ordinary glass plate with a space, and the periphery of the glass plate is sealed. We need to think of a way to use it as a. This reduces the cost per unit area of the window glass by -1;l, and the heat-reflecting glass as a product also becomes considerably heavy. Furthermore, when a blue metal thin film is used, although it has excellent heat ray reflectivity, it also has a high reflectance in the visible range, and reflects light rays with a glittering effect to the naked eye, creating a so-called mirror effect, which is preferable for practical purposes. There may be no.

On the other hand, heat-reflecting glass that can be used as a single glass plate includes a glass plate L coated with a thin film of a metal oxide such as tin, titanium, cobalt, chromium, or iron. These oxide thin films have good mechanical and chemical durability, but with some exceptions (indium oxide with tin, tin oxide with antimony), the heat ray reflection performance is poor. is considerably inferior to precious metals. From this point of view, it has heat ray reflection performance close to that of precious metals, has improved abrasion resistance and chemical resistance, has mechanical and chemical durability equivalent to or better than metal oxide thin films, and can be used as a single plate. A heat ray reflective glass plate coated with a single layer of titanium nitride has been proposed as a heat ray reflective glass plate. The heat ray reflection performance of the titanium nitride film is due to the fact that the titanium nitride film is in a state in which it simultaneously has delocalization of outer shell electrons, which is a characteristic of the metallic state, and at least partial covalent bonds. In other words, outer shell electrons conduct
Titanium nitride (T i N ) B'A becomes electrons and contributes to improving the heat reflectivity of titanium nitride (T i N ) B'A. On the other hand, covalent bonds contribute to improving mechanical strength, and nitrogen, which is an a-element, forms silanol on the glass surface. Forms chemically stable bonds with groups, etc.
What does it mean to increase wearing power? Such excellent properties of the titanium nitride film are obtained when the film is formed of fully crystallized titanium nitride. Such a titanium nitride coating having a high degree of crystallinity can be obtained by performing the step-11 formation while heating the substrate on which the coating is to be formed to a high temperature. On the other hand, when a titanium nitride film is formed at a low temperature, for example, at a substrate temperature of 200°C or higher, it hardly crystallizes, and such a pattern has no optical or electrical properties. In terms of properties, it has properties close to those of titanium nitride (TiN), but its mechanical and chemical properties are insufficient.

The inventor focused on a low-temperature method for forming a titanium nitride film that has good productivity and can be obtained at low cost, although it is insufficient in terms of mechanical and chemical properties. Mechanical properties of titanium coatings, especially wear resistance,
We also attempted to improve the chemical properties, especially acidity and alkali resistance. As a result, by sandwiching a titanium nitride film between titanium oxide films to form a three-layer structure, properties such as wear resistance and chemical resistance are improved compared to a single layer of titanium nitride film formed by the above-mentioned film formation method. was recognized, and Y-kan-
+It was found that it was durable for use (4) and was also found to be convenient in terms of production.

The present inventor further conducted various studies on a method for forming a five-layer laminated film in which a titanium nitride film is sandwiched between titanium oxide films with higher productivity and at a lower cost. For example, the simplest method for creating a multilayer film having a three-layer structure as described above by sputtering is to perform sputtering in an Ar atmosphere using titanium oxide and titanium nitride as targets, respectively. However, sintered target generally requires time and effort to mold, is expensive, and has the drawback that the target cannot be recycled and used. Furthermore, titanium oxide has the disadvantage that only R, F, and sputtering can be performed. Therefore, as another sputtering method to create such a three-layer film.

Metallic titanium is used for all the re-gets, and when applying titanium nitride, reactive sputtering is performed using a mixture of At and N2 as the sputtering gas, and titanium oxide (TiO
There is a method of performing reactive sputtering by using a mixed gas of A and 02 in the 1't-9 sputtering gas when inspecting each layer. It becomes necessary to completely replace the waste, which becomes uneconomical in terms of time, and this increases the cost of the product
-Leads to A. In order to eliminate this disadvantage, the present inventors attempted to intentionally introduce 02 with a slight radius into the mixed scum of Ar and N2 to perform reactive sputtering. Figure 4 shows that the composition ratio of Ar, N2 and 02 is 85:1.
The optical constants of the film (refractive index n, extinction coefficient k
) and the adhesion speed. Figure 4 shows that the optical constants depend considerably on the deposition rate, and the I-no deposition rate is 19
．． At a high place with 5 people and 7 seconds, the refractive index n is 1.43 and the extinction coefficient is 2.42, whereas S,
It can be seen that at a low temperature of 0/see, the refractive index increases to 2.60, which is more than 1, while the extinction coefficient drops to almost zero. This means that the slower the speed, the more titanium oxide (TiO2) the film becomes.
It can also be assumed that it is more like titanium nitride (TiN) than a fast rod. In other words, when the rate of oxidation is slow, oxygen is more reactive than nitrogen, so even if the amount of oxygen is less, the reaction between titanium and oxygen mainly occurs, and titanium oxide (Ti02) is formed, but as the deposition rate increases, the reaction cannot catch up because there is less oxygen, and a larger amount of nitrogen and titanium now react, making the film more like titanium nitride. be.

Undeveloped If was invented based on this knowledge, and when forming a laminated film of a titanium oxide layer and a titanium nitride layer on a substrate, a first metal titanium target for forming a titanium oxide layer is used. The substrate was introduced into a vacuum chamber of a sputtering film forming apparatus in which a target and a second metal titanium target for forming a titanium nitride layer were sequentially arranged in the same vacuum chamber, and a mixed scum of Ar, 02, and N2 was introduced into the vacuum chamber. a titanium oxide layer by performing reactive sputtering in the presence of a titanium oxide layer to form a titanium oxide layer when the substrate faces the first metal titanium target and a titanium nitride layer when the substrate faces the second metal titanium target. A laminated film consisting of a titanium nitride layer and a titanium nitride layer can be manufactured continuously in the same vacuum chamber with high productivity and at low cost without breaking the vacuum.

The method of the present invention uses a two-layer laminated film 11 consisting of a titanium oxide layer and a titanium nitride layer formed thereon! J, a two-layer laminated coating consisting of a titanium nitride layer and a titanium oxide layer formed on top of the titanium nitride layer, or a three-layer laminated coating consisting of a titanium nitride layer sandwiched between titanium oxide layers, or a titanium oxide layer and a nitride layer. It can be used to form laminated coatings consisting of multiple titanium layers on various substrates. For example, in the method of the present invention, by sandwiching a titanium nitride layer between titanium oxide layers, the scratch resistance of the titanium nitride layer can be improved while maintaining the heat ray reflection performance inherent in the titanium nitride layer.

Not only when forming heat ray reflected waves II of the 3M structure with improved chemical resistance on glass plate surfaces, but also when forming titanium oxide layers and titanium nitride on various glass substrates, ceramic substrates, plastic substrates, and various other substrates. It can be applied to the case of forming a laminated film of multiple layers.

A reactive sputtering apparatus 1 according to a specific example of the apparatus for implementing the present invention shown in FIG. Arrange the atmosphere inside the vacuum chamber 2 with Ar.
A mixture of N2 and 02 is formed, and the substrate 5 is
While transporting the substrate 5 at a constant speed, or by stopping the substrate 5 at each target location each time, a two-layer laminated film is continuously deposited on the substrate surface by reactive sputtering in the same vacuum chamber without breaking the vacuum. It is a device that can be formed. For example, if a low voltage is applied to the first metal titanium target 3 and a high voltage is applied to the second metal titanium target 4 while moving the base body 5 in the direction of arrow A in the vacuum chamber 2, At the first metal titanium target 3, a titanium oxide layer is formed on the surface of the plate 5 by reactive sputtering with the 02 gas in the mixed gas,
At the second metal titanium target 4, a titanium nitride layer is formed on the titanium oxide layer formed on the surface of the base 5 by reactive sputtering with N2 gas in the mixed gas. Further, while moving the base body 5 in the direction of arrow A in the vacuum chamber 2, applying a high voltage to the first metal titanium target 3 and applying a low voltage to the second metal titanium target 4, the first At the location of the metal titanium target 3, a titanium nitride layer is formed on the substrate 5 surface by reaction sputtering with N2 gas in the mixed gas, and at the location of the second metal titanium target 4, the 02 slag in the 14 gas mixture is formed. A titanium oxide layer is formed on the titanium nitride layer by reactive sputtering with the titanium nitride layer.

Further, the reactive sputtering apparatus 1 according to a specific example of the apparatus for implementing the present invention shown in FIG.
Three metal titanium targets 3, second metal titanium targets 4, and third metal titanium targets 6 are arranged in parallel, and the atmosphere in the vacuum chamber 2 is changed to a mixed curtain of Ar, N2, and 02. While conveying the substrate 5 continuously at a constant speed, or by stopping the substrate 5 at each target location each time, a three-layer laminated coating is applied to the surface of the substrate 5 by reactive sputtering in the same vacuum chamber. This is a device that allows continuous formation without breaking the material.

For example, while moving the substrate 5 in the direction of arrow A in the vacuum chamber 2, a low voltage is applied to the first metal titanium target 3, a high voltage is applied to the second metal titanium target 4, or When a low voltage is applied to the third metal titanium target 5, 0.0% is applied to the first metal titanium target 3 in the mixed gas. A titanium oxide layer is formed on the surface of the substrate 5 by reaction sputtering with the gas, and N in the mixed gas is formed at the second metal titanium target 4.
A titanium nitride layer is formed on the titanium oxide layer by the reaction sputtering with the 02 gas in the mixed gas, and a titanium nitride layer is formed on the titanium nitride layer by the reaction sputtering with the 02 gas in the mixed gas at the third metal titanium target 6. is formed.

In carrying out the present invention, the vacuum chamber in which reactive sputtering is carried out is kept at a vacuum level of approximately 4-OX 1O-3 Torr, and Ar scum is used as the sputtering gas.
N2 gas and 0.0% as reaction gases. Gas is introduced into the vacuum chamber, and a metallic titanium target plate is used as the target lift. The composition ratio of the above-mentioned mixed gas of Ar, N2, and 02 is Ar>N2>02, more preferably Ar is 6
5-90Vo1%.

It is necessary to set N2 to 10-30 Vo1% and 02 to 1-5 Vo1% in order to create a titanium nitride layer and a titanium oxide layer separately by changing the power applied to each target lift in such a mixed gas. be. The power applied to the metallic titanium target for forming the titanium oxide layer varies depending on the type of equipment, applied voltage, gas composition, and other conditions, but in the equipment and conditions used by the present inventor, for example, Approximately 1.2W to 2.6W per area,
In addition, the power applied to the metal titanium target for forming the titanium nitride layer varies depending on the type, applied voltage, gas composition, and other conditions, as in the case of forming titanium oxide. The apparatus and conditions used were, for example, approximately 2.7 W to 4.2 W per unit area. Furthermore, when forming a film on a substrate by reactive sputtering in a vacuum chamber, the substrate may be conveyed in one direction, or the substrate may be stopped at each target position. . Note that the sputtering apparatus shown in Figure 1.2 described above uses two metallic titanium targets.
It is possible to form a layered coating of 2R to 3 layers by connecting or arranging three layers in parallel, and it is possible to form a coating while conveying the substrate in one direction.
After passing through the second metal titanium target, it can be returned to the first metal titanium target again for overcoating.

Furthermore, in the present invention, a plurality of titanium metal targets are arranged horizontally, vertically, or in the rotational direction in the same vacuum chamber, and reactive sputtering is performed within the same vacuum chamber. Target--you can also set up a partition.

In the case of forming a laminated film on the substrate surface according to the present invention, the temperature of the substrate may be at room temperature or may be heated to 5 or 200° C. or less. Note that if a single layer of titanium nitride is formed on a low-temperature substrate, the titanium nitride layer will have inferior mechanical properties such as wear resistance, and chemical properties such as acid resistance and alkali resistance. By laminating a titanium layer and a titanium oxide layer, or by sandwiching a titanium nitride layer with a titanium oxide layer, the mechanical and chemical properties of the titanium nitride layer can be improved.
For example, a titanium nitride layer with excellent mechanical properties and chemical properties can be obtained according to the present invention even at a low temperature of about 200°C.

Furthermore, when changing the thickness of the titanium oxide layer or titanium nitride layer formed according to the present invention, it is easy to change the thickness by changing the electric power applied to each target or by changing the passing speed of the target portion of the base body. What you do is ÷ chant. If the thickness cannot be controlled with only the applied voltage, you can change the atmosphere of the sputtering gas.For example, if there is 02 gas in the mixed gas in the vacuum chamber,
If you increase the gas fraction, it will be faster1. % deposition rate to form titanium butyride or titanium nitride layers to some extent.

By the present invention, it is desired to obtain a multilayer coating with particularly excellent mechanical properties such as wear resistance and chemical properties such as acid resistance and alkali resistance, such as a three-layer multilayer coating in which a titanium nitride layer is sandwiched between titanium oxide layers. In some cases, the thickness of the titanium oxide layer has a particularly large effect on wear resistance, so it is preferable that the thickness is at least 100 Å or more. Note that if the thickness of the titanium oxide layer on both sides is less than 100, it is not practical in terms of wear resistance. Also, by changing the thickness of the upper and/or lower titanium oxide layer, or by changing the thickness of the titanium nitride layer, visible light transmittance and reflectance can be improved by utilizing the interference effect or antireflection effect. However, the titanium oxide layer in the present invention is not limited to TiO2゜TiOx, etc., but also includes layers made of titanium oxide, etc., containing a small amount of titanium oxide analogues, such as nitrogen or titanium nitride, etc. Also, the titanium nitride layer is TiN,
The layer is not limited to TiNx, but also includes layers made of titanium nitride analogues, such as titanium nitride containing a small amount of oxygen or titanium oxide. In the present invention, since the titanium oxide layer and the titanium nitride layer are created by the reactive sputtering method in a mixed gas of A and N2, the titanium oxide analog layer and titanium nitride analog layer as described above are formed. In this way, Ar and N2
Titanium nitride (TiN
) When comparing the spectral properties of the analogue layer with those of a titanium nitride (TiN) layer prepared in a normal Ar and N2 mixed gas, almost no difference was observed, at least in the wavelength region longer than near-infrared. From this point of view, it is clear that the oxygen and titanium oxide contained in titanium nitride have almost no effect on the heat-reflecting performance of the film. When used as a layer, it is comparable in terms of heat ray reflective performance to a heat ray reflective glass with 1 layer and 4 titanium nitride layers.

Examples of the present invention will be described below.

EXAMPLE Three titanium metal targets were set in parallel in a vacuum chamber of a reaction sputtering apparatus as shown in FIG. A 2.0 mm mm-talime glass substrate whose surface had been polished and cleaned was placed into the vacuum chamber from before the first metal titazo target. At this time, the position was set so that the film would not touch the substrate during press sputtering. Next, the vacuum chamber was evacuated to 5.0X 1O-5 Torr or less using an oil diffusion pump, and then a mixed gas of Ar:n:02=85:12:3 was introduced into the vacuum chamber. Furthermore, during the evacuation, the substrate temperature was increased to 70''C +f.A high frequency power source of 1.4KV was applied to the 1st Wi and 3rd titanium metal targets.
The arrival speed was set to 5.5 people/sec, and a 2.4KV high frequency power supply was applied to the second target so that the arrival speed was 14.7 people/set. ,
Press sputtering was performed for about 10 minutes. In addition, the pressure in the tank during press sputtering is also 4. It was adjusted to OX 1O-3 Torr. Thereafter, the glass substrate was moved over these three targets at a transport speed of 22 cm/+in, and a titanium oxide layer with a thickness of 150 mm was formed on the glass substrate, a titanium nitride layer with a thickness of 400 mm was formed on the titanium oxide layer, and a titanium nitride layer with a thickness of 400 mm was formed on the titanium oxide layer. A three-layer laminated coating with a thickness of 150 mm on the titanium nitride layer (total thickness of 70 mm)
0 people) were obtained. The optical properties and color properties of this laminated film were measured and are shown in Figure 3.The average visible light transmittance was 28.0%, the average visible light reflectance was 18.4%, and the color coordinates of the transmitted light were x=0.2El! 3. y=0.284 indicates an old color system, and the color coordinates of the reflected light are x=0.423,
1 = 0.39B, showing a golden color. The solar energy reflectance was 38.4%, and the solar energy absorption was 43.4%.

In FIG. 3, curve 10 shows the transmittance curve, and curve 12 shows the reflectance curve. This m-layer liquid film is o, iMl.

Even after 2 hours of immersion in a constant sodium hydroxide solution at 80°C, no change was observed at all. Furthermore, no change was observed when a similar treatment was applied to a solution of 0.1N oxalic acid at 80°C.

Furthermore, a load of 382 g/- was applied to the felt impregnated with a suspension of kaolin and water at a ratio of 1:5, 500 times.
Even when the first and second sides were moved back and forth, almost no change was observed.

Comparative Example After evacuation was carried out in the same manner as in the Example, Ar:
A mixed gas of N2 = 8:2 was introduced into the vacuum chamber. In addition, only the second metal titanium target has a 2.4
A high frequency power source of KV was applied and press sputtering was performed for 10 minutes. When this target lift-h was moved around the glass substrate at a transport speed of 22 co+/see, a titanium nitride (TiN) film with a thickness of about 400 Å was obtained. The optical properties and color properties of this film were measured and were as shown in Figure 3.
The average visible light transmittance is 20.0%, and the average visible light reflectance is 34.
．． At 5%, what are the color coordinates of the transmitted light? =0.286, y-
0,305, the color coordinates of the reflected light are x=0.337, y=
It was 0.331. It was also the sun. In FIG. 3, curve 13 shows a transmittance curve, and curve 14 shows a reflectance curve. When this film was also subjected to a 90° C. immersion test in the same manner as in the examples, about 50% of the film disappeared when exposed to oxalic acid, and the reflected color became reddish when exposed to sodium hydroxide. Further, when the felt was reciprocated 500 times under the same conditions as in the example, many lines with no peeling of H were formed, and it was confirmed that the film was clearly worn.

As can be seen from the spectral characteristics diagrams of the above examples and comparative examples, even if a titanium nitride layer is sandwiched with a titanium oxide layer to form a three-layer laminated coating, the reflection and transmission characteristics in the infrared region are not as good. It is clear that there is no effect on Further, according to Example 1, it is clear that a solar energy reflecting film having good abrasion resistance, chemical resistance, and relatively high heat ray reflection performance can be produced at low temperature and at low cost.

As described above, according to the present invention, titanium oxide 7-
A laminated film of the 2nd layer and the titanium nitride layer was prepared by placing a plurality of metal titanium target 4° in the same vacuum chamber, and by making a mixed gas of Ar, N2, and 02 exist in this vacuum chamber, each metal titanium target was The titanium nitride layer and the titanium oxide layer can be separately created by performing reactive sputtering by changing the voltage applied to the target, so film formation can be performed sequentially and continuously in one vacuum chamber without breaking the vacuum inside the chamber. Moreover, since only one type of target lift is used, productivity is high, and a laminated film of a titanium oxide layer and a titanium nitride layer can be obtained with good workability at low cost.

The method of the present invention can be preferably used, for example, for manufacturing solar energy reflective glass in which a three-layer heat ray reflective coating is formed by sandwiching a titanium nitride layer with a titanium oxide layer on a glass plate surface. According to this method, it is possible to produce solar energy reflective glass at low cost, which has excellent mechanical properties such as abrasion resistance, chemical properties such as alkali resistance and acid resistance, and has sufficient heat ray reflection performance.

[Brief explanation of the drawing]

Fig. 1.2 is a schematic diagram of a reactive sputtering apparatus used to carry out the method of the present invention, Fig. 3 is a spectral characteristic diagram of samples obtained in Examples and Comparative Examples, and Fig. 4 The figure shows Ar and N. 2 is a diagram showing the relationship between the refractive index n and the attenuation coefficient of 1 for films created by varying the deposition rate in the sputtering atmosphere 11 in the presence of mixed scum of F and 02. FIG. 1: Reaction sputtering device 2: Vacuum tank 3: First metal titanium target 4: Second metal titanium target 5: Substrate 6: Third metal titanium target Dttp, Rati CA/δ] Procedural official document (method) % formula % 1. Indication of the case 1982 Patent Application No. 41350 2. Name of the invention Method for forming a laminated film by reactive sputtering method 3. Make amendments Relationship to this case Patent applicant address 2-1-2 Marunouchi, Chiyoda-ku, Tokyo Name (
004) Asahi Glass Co., Ltd. 4, Agent May 29, 1980 (shipment date) 6. Number of inventions increased by amendment None or more

Claims (1)

[Scope of Claims] (1) In a method of forming a laminated liquid of a titanium oxide layer and a titanium nitride layer on a substrate by a reactive sputtering method, a first metallic titanium target for forming a titanium oxide layer and a titanium nitride layer are formed. The substrate is introduced into a vacuum chamber in which a second metal titanium target for layer formation is sequentially arranged in the same vacuum chamber, and reactive sputtering is performed in the presence of a mixed gas of Ar, 02, and N2 to form the substrate. A method for forming a laminated film by a reactive sputtering method, which comprises forming a laminated film of a titanium oxide layer and a titanium nitride layer thereon. (2) Ar and 0. The composition ratio of the mixed gas of and N2 is At
A method for forming the laminated layer i by a reactive sputtering method according to claim 1, characterized in that >N2>02. ('3) In a mixed gas of Ar, 02, and N2, the power applied to the second metal titanium target is higher than the power applied to the first metal titanium target to separately create a titanium oxide layer and a titanium nitride layer. A method for forming a laminated film by a reactive sputtering method according to claim 1, characterized in that: (4) Formation of a laminated coating by the reactive sputtering method according to claim 1, characterized in that the laminated coating has a laminated structure consisting of a titanium oxide layer, a -I layer, and a titanium nitride layer. Method. (5) A method for forming a laminated film by a reactive sputtering method according to claim 1, wherein the laminated film has a laminated structure consisting of a titanium nitride layer and a titanium oxide layer on top of the titanium nitride layer. . (6) Claim 1, characterized in that the laminated film has a 1R layer structure consisting of a titanium oxide layer, a titanium nitride layer on top of the titanium oxide layer, and a titanium oxide layer on top of the titanium oxide layer.
A method for forming lamination liquid 11 by the reactive sputtering method described in 1. (7) In a method of forming a three-layered layered film in which a first titanium oxide layer, a titanium nitride layer, and a second titanium oxide layer are sequentially laminated on a substrate by a reactive sputtering method, the first oxide A first metallic titanium target for the titanium layer, a second metallic titanium target for the titanium nitride layer, and a third metallic titanium target for the second titanium oxide layer are sequentially arranged in the same vacuum chamber. A substrate is introduced into a vacuum chamber made of a mixture of A, 02, and N2, and reactive sputtering is performed in the presence of a mixed gas of A, 02, and N2.
Ability to form a laminated film by the reactive sputtering method according to claim 6, characterized in that an A-layer film with a three-layer structure consisting of a titanium oxide layer, a titanium nitride layer, and a second titanium oxide layer is formed. Law. (8) In a method of forming a three-layer multilayer coating in which a first titanium oxide layer, a titanium nitride layer, and a second titanium oxide layer 4 are sequentially stacked on a substrate by a reactive sputtering method, the first oxide A first metal titanium target for the titanium layer, a second metal titanium target for the titanium nitride layer, and a third metal titanium target for the second titanium oxide layer are sequentially arranged in the same vacuum chamber. Ar, 02, and N2 are introduced into the vacuum chamber, and while the substrate is transported from the first metal titanium target toward the third metal titanium target, Ar, 02, and N2 are introduced into the vacuum chamber without breaking the vacuum in the vacuum layer. 8. A method for forming a multilayer film by a reactive sputtering method according to claim 7, characterized in that the multilayer film having the three-layer structure is formed on the substrate by performing schuntering in the presence of a mixed gas. (9) In a mixed gas of Ar, 02, and N2, the power applied to the second metal titanium target is higher than the power applied to the first and third metal titanium targets to form a titanium oxide layer and a titanium nitride layer. Particularly 7. A method for forming a laminated film by the reactive sputtering method according to item 8, characterized in that it is made separately. (10) Ar and 0. The composition ratio of the mixed gas of and N2 is
Ar:02: N2 = (85~90) ,: (1
~5): (10-30) A method for forming a laminated film by a reactive sputtering method according to claim 1, wherein: (10-30).