阅读说明：本技术 等离子体处理装置用部件 (Component for plasma processing apparatus ) 是由 花待年彦 诸田修平 高原刚 泷本优 横山响 光田拓史 荒木良仁 味泽贤吾 于 2019-07-17 设计创作，主要内容包括：本发明的等离子体处理装置用部件包括：铝基材；以及氧化被膜,其形成在铝基材上,具有多孔质结构,其中,氧化被膜包括：第一氧化被膜,其形成在铝基材的表面上,第二氧化被膜,其形成在第一氧化被膜的与铝基材侧相反的一侧,以及第三氧化被膜,其形成在第二氧化被膜的与第一氧化被膜侧相反的一侧,第一氧化被膜比第二氧化被膜及第三氧化被膜硬,在第一氧化被膜、第二氧化被膜和第三氧化被膜的各被膜中形成的孔被封孔。(The member for a plasma processing apparatus of the present invention includes: an aluminum substrate; and an oxide film formed on the aluminum substrate and having a porous structure, wherein the oxide film comprises: a first oxide film formed on the surface of the aluminum substrate, a second oxide film formed on the opposite side of the first oxide film from the aluminum substrate, and a third oxide film formed on the opposite side of the second oxide film from the first oxide film, the first oxide film being harder than the second oxide film and the third oxide film, pores formed in each of the first oxide film, the second oxide film, and the third oxide film being sealed.)

1. A component for a plasma processing apparatus, comprising:

an aluminum substrate; and

an oxide film formed on the aluminum substrate and having a porous structure, wherein,

the oxide film includes:

a first oxide film formed on the surface of the aluminum substrate,

a second oxide film formed on the opposite side of the first oxide film from the aluminum substrate side, and

a third oxide film formed on the second oxide film on the opposite side to the first oxide film,

the first oxide film is harder than the second oxide film and the third oxide film,

pores formed in each of the first oxide film, the second oxide film, and the third oxide film are sealed.

2. The member for plasma processing apparatus according to claim 1,

further comprising a ceramic thermal spray film formed on the opposite side of the oxide film from the aluminum substrate side.

3. The member for plasma processing apparatus according to claim 1 or 2,

the hardness of the second oxide film gradually increases from the third oxide film side toward the first oxide film side.

4. The member for plasma processing apparatus according to any of claims 1 to 3,

the porosity of the oxide film is 1% or more and 2% or less.

5. The member for plasma processing apparatus according to any of claims 1 to 4,

the first oxide film has a barrier layer at a portion in contact with the aluminum substrate,

the barrier layer has a thickness of 80nm or more and 210nm or less.

6. The member for plasma processing apparatus according to any of claims 1 to 5,

the oxide film is sealed by alumina hydrate,

the alumina hydrate is a hydrate of 1.4 or more and 2 or less.

7. The member for plasma processing apparatus according to any one of claims 1 to 6,

the oxide film has a thickness of 70 [ mu ] m or more and 130 [ mu ] m or less.

Technical Field

The present invention relates to a member for a plasma processing apparatus used for the plasma processing apparatus.

Background

As a member used for a plasma processing apparatus, a member for a plasma processing apparatus is known in which an oxide film is formed on an aluminum base material and a thermal spray film is formed on the oxide film (see, for example, patent documents 1 and 2). By providing the thermal spray film on the oxide film as described above, the plasma resistance of the member for a plasma processing apparatus can be improved.

Patent document 1 discloses a vacuum processing apparatus for processing a substrate to be processed by a plasma reaction, in which an oxide coating layer is formed on a surface of an electrode body disposed in a vacuum processing chamber, and an alumina thermal spray coating film is formed on a surface of the oxide coating layer to form a multilayer structure. According to patent document 1, the alumina thermal spray coating protects the oxide coating layer, thereby preventing the oxide coating layer from cracking or peeling off, preventing the generation of particles, prolonging the service life, and reducing the frequency of exchange, thereby improving the operation efficiency of the device.

Patent document 2 discloses, as a treatment of a member having an oxidation-treated film formed on the surface of a base material, an anodic oxidation treatment in a method for producing a plasma treatment container inner member in which a thermal spray film is formed on the oxidation-treated film, the treatment including a step of immersing the base material in a basic organic solvent and a step of generating plasma discharge in the basic organic solvent. Examples of the internal member of the plasma processing vessel include an electrode protecting member and an insulating ring. In patent document 2, by performing the above treatment, the adhesion of the thermal spray film to the surface of the base material is improved.

Patent document 1: japanese patent laid-open No. 2000-114189

Patent document 2: japanese patent No. 4430266

Disclosure of Invention

However, due to the high energy in the plasma processing process in recent years, a member for a plasma processing apparatus is required to have high dielectric strength.

The present invention has been made in view of the above problems, and an object thereof is to provide a member for a plasma processing apparatus having a high dielectric strength.

In order to solve the above problems and achieve the object, a member for a plasma processing apparatus according to the present invention includes: an aluminum substrate; and an oxide film formed on the aluminum substrate and having a porous structure, wherein the oxide film includes: a first oxide film formed on a surface of the aluminum substrate, a second oxide film formed on a side of the first oxide film opposite to the aluminum substrate side, and a third oxide film formed on a side of the second oxide film opposite to the first oxide film side, the first oxide film being harder than the second oxide film and the third oxide film, pores formed in each of the first oxide film, the second oxide film, and the third oxide film being sealed.

In the above invention, the member for a plasma processing apparatus according to the present invention further includes a ceramic thermal spray film formed on a side of the oxide film opposite to the aluminum substrate side.

In the member for a plasma processing apparatus according to the present invention, in the above-described invention, the hardness of the second oxide film is gradually increased from the third oxide film side toward the first oxide film side.

In the member for a plasma processing apparatus according to the present invention, the porosity of the oxide film is 1% or more and 2% or less.

In the member for a plasma processing apparatus according to the present invention, the first oxide film has a barrier layer in a portion in contact with the aluminum substrate, and the barrier layer has a thickness of 80nm or more and 210nm or less.

In the member for a plasma processing apparatus according to the present invention, the oxide film is sealed with an alumina hydrate, and the alumina hydrate is a hydrate of 1.4 or more and 2 or less.

In the member for a plasma processing apparatus according to the present invention, the oxide film has a thickness of 70 μm or more and 130 μm or less.

According to the present invention, a member for a plasma processing apparatus having a high dielectric strength can be obtained.

Drawings

Fig. 1 is a sectional view showing a structure of a member for a plasma processing apparatus according to an embodiment of the present invention.

Fig. 2 is an enlarged cross-sectional view of a part of the member for the plasma processing apparatus shown in fig. 1.

Fig. 3 is a microscope image showing an example of an oxide film in a member for a plasma processing apparatus according to an embodiment of the present invention, and is a microscope image showing a cross section of the oxide film.

Fig. 4 is an SEM image showing an example of an oxide film in a member for a plasma processing apparatus according to an embodiment of the present invention, and is an SEM image showing a cross section of the oxide film.

Fig. 5 is an SEM image showing an example of an oxide film in a member for a plasma processing apparatus according to an embodiment of the present invention, and is an SEM image showing a cross section of the oxide film.

Fig. 6 is a diagram showing physical properties of a member for a plasma processing apparatus according to an embodiment of the present invention and a member for a plasma processing apparatus according to a comparative example.

Detailed Description

The embodiments for carrying out the present invention will be described in detail below with reference to the accompanying drawings. The present invention is not limited to the following embodiments. In the following description, the drawings referred to are only schematic representations of shapes, sizes, and positional relationships for understanding the contents of the present invention. That is, the present invention is not limited to the shapes, sizes, and positional relationships illustrated in the drawings.

Fig. 1 is a sectional view showing a structure of a member for a plasma processing apparatus according to an embodiment of the present invention. Fig. 2 is an enlarged cross-sectional view of a part (region R) of the member for a plasma processing apparatus shown in fig. 1. The member 1 for a plasma processing apparatus shown in fig. 1 includes: a base material 10 which is an insulating substrate; an oxide film 20 formed on a part of the surface of the substrate 10, and a thermal spray film 30 provided on the opposite side of the oxide film 20 from the substrate 10 side. The member 1 for a plasma processing apparatus is used as a material of a member in a plasma processing apparatus, for example, an electrode or an electrode protection member, and is configured by processing a base material formed of the base material 10, the oxide film 20, and the thermal spray film 30.

The substrate 10 is an aluminum substrate formed using aluminum, an alloy containing aluminum as a main component, or aluminum oxide.

The thermal spraying film 30 is a ceramic thermal spraying film formed using ceramic.

Fig. 3 is a microscope image showing an example of an oxide film in a member for a plasma processing apparatus according to an embodiment of the present invention, and is a microscope image showing a cross section of the oxide film. Fig. 4 and 5 are Scanning Electron Microscope (SEM) images showing an example of the oxide film in the member for a plasma processing apparatus according to the embodiment of the present invention, and are SEM images showing a cross section of the oxide film. Shown in FIGS. 3 to 5 are regions (coatings) corresponding to the respective portions of the oxide coating shown in FIG. 2.

The oxide film 20 is an alumina film having a three-layer structure formed by anodic oxidation treatment. The oxide film 20 is composed of a first oxide film 21, a second oxide film 22, and a third oxide film 23, wherein the first oxide film 21 is formed on the surface of the substrate 10, the second oxide film 22 is laminated on the side of the first oxide film 21 opposite to the substrate 10 side, and the third oxide film 23 is laminated on the side of the second oxide film 22 opposite to the first oxide film 21 side (see, for example, fig. 2 and 3).

The first oxide film 21 has a higher hardness than the second oxide film 22. The hardness of the second oxide film 22 is higher than that of the third oxide film 23. That is, the hardness of the oxide film 20 gradually decreases from the substrate 10 side toward the thermal spray film 30 side. The hardness of the first oxide film 21 is preferably 400Hv or more and 430Hv or less. The hardness of the second oxide film 22 is preferably 200Hv to 380 Hv. The hardness of the third oxide film 23 is preferably 40Hv to 80 Hv. The hardness of the second oxide film 22 gradually increases from the third oxide film 23 side toward the first oxide film 21 side.

When the hardness of the first oxide film 21 is less than 400Hv, the wear resistance and the dielectric strength may be reduced. On the other hand, if the hardness of the first oxide film 21 is higher than 430Hv, cracks may be formed in the film.

Of the lengths (thicknesses) of the first oxide film 21, the second oxide film 22, and the third oxide film 23 in the overlapping direction, the second oxide film 22 is the largest and the first oxide film 21 is the smallest. Specifically, the first oxide film 21 is 80nm or more and 210nm or less. The second oxide film 22 is preferably 60 μm or more and 100 μm or less. The third oxide film 23 is preferably 20 μm or more and 30 μm or less. The thickness of the oxide film 20 is preferably 70 μm to 130 μm, and particularly preferably 70 μm to 120 μm.

The first oxide film 21 includes: a coating layer 21a formed on the second oxide coating 22 side; and a barrier layer 21b formed on the substrate 10 side. The barrier layer 21b is a nonconductive film formed on the surface of the substrate, and is a layer that supports the growth of the film (film layer 21a) when the film is formed. The thickness of the barrier layer 21b is preferably 80nm or more and 210nm or less. At this time, the content of the barrier layer 21b in the first oxide film 21 is higher than that of the film layer 21 a. The conventional barrier layer has a thickness of 30nm to 40nm in a film equivalent to the first oxide film 21. The coating layer 21a and the barrier layer 21b have the same hardness, and preferably have the above hardness (400Hv to 430 Hv).

The porosity of the oxide film 20 is 1% to 2%. In the oxide film 20, the first oxide film 21, the second oxide film 22, and the third oxide film 23 are porous films, and the pores of each film are filled with alumina hydrate. The alumina hydrate is preferably a hydrate of 1.4 or more and 2.0 or less. In the first oxide film 21, the pores are formed in the film layer 21 a.

Next, a method for manufacturing the component 1 for a plasma processing apparatus will be described. First, the above-described substrate 10 is prepared. An oxide film 20 is formed on the substrate 10. In order to form the oxide film 20, first, a third oxide film 23 is formed. Then, a second oxide film 22 is formed. After the second oxide film 22 and the third oxide film 23 are formed, the first oxide film 21 is formed. At this time, as the first oxide film 21, film layers (the film layer 21a and the barrier layer 21b) are formed by an anodic oxidation treatment. Then, the pores formed in the coating film are filled with alumina hydrate. Thus, the oxide film 20 is formed on the substrate 10. Then, the thermal sprayed film 30 is formed on the side of the oxide film 20 opposite to the side of the substrate 10.

The physical properties of the member 1 for a plasma treatment apparatus having a three-layer oxide film (example) and the member for a plasma treatment apparatus having a single-layer oxide film (comparative example) produced in the above manner will be described with reference to fig. 6. Fig. 6 is a diagram showing physical properties of a member for a plasma processing apparatus according to an embodiment of the present invention and a member for a plasma processing apparatus according to a comparative example. In fig. 6, "porous diameter" means an average value of the diameters of pores at a porous site, and "porous number" means the number of pores at a porous site.

As shown in fig. 6, it is understood that the dielectric strength of the member 1 for a plasma processing apparatus according to the example was higher than that of the member for a plasma processing apparatus according to the comparative example both before and after heating.

In addition, the porosity of the member for plasma treatment apparatus 1 according to the example was lower than that of the member for plasma treatment apparatus according to the comparative example, and was within the above range.

According to the above embodiment, by adopting the three-layer structure of the first oxide film 21, the second oxide film 22, and the third oxide film 23 for the oxide film 20 formed between the base material 10 and the thermal spray film 30, and making the first oxide film 21 on the base material 10 side harder than the other films (the second oxide film 22 and the third oxide film 23), it is possible to obtain a member for a plasma processing apparatus having a high dielectric strength.

As described above, the present invention may include various embodiments and the like not described herein, and various design changes and the like may be made without departing from the scope of the technical idea defined by the claims.

In addition, in the above embodiment, the member for a plasma processing apparatus 1 in which the thermal spray film 30 is formed on the oxide film 20 was described as an example, but the member for a plasma processing apparatus may not have the thermal spray film 30, that is, may be constituted only by the base material 10 and the oxide film 20.

As described above, the member for a plasma processing apparatus according to the present invention is suitable for realizing a member for a plasma processing apparatus having a high dielectric strength.

Description of the symbols

1 component for plasma processing apparatus

10 base material

20 oxidation coating

21 first oxide film

21a coating layer

21b barrier layer

22 second oxide coating

23 the third oxide film

30 thermal spray film