JP3148878B2 - Aluminum plate, method of manufacturing the same, and anti-adhesive cover using the aluminum plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum plate, a method for manufacturing the same, and an anti-adhesive cover using the aluminum plate. More specifically, the present invention relates to an aluminum plate suitable for use in a microwave plasma processing apparatus and the like, and a method for manufacturing the same. And an anti-adhesion cover using the aluminum plate.

[0002]

2. Description of the Related Art Microwaves and the like are introduced into a reaction vessel under reduced pressure or low gas pressure to generate gas discharge to generate plasma, and the plasma is guided to the substrate surface to perform processing such as etching and resist removal. Or CVD
2. Description of the Related Art A plasma processing apparatus for forming a thin film by using such a method has become indispensable in the manufacturing process of highly integrated semiconductor devices and the like today.

In addition, plasma is generated more efficiently,
Alternatively, a magnetic field microwave plasma processing apparatus that applies a magnetic field to confine the plasma in a certain area or an electron cyclotron resonance (ECR)
e) An apparatus for generating plasma by excitation has an advantage that plasma having high activity can be generated in a low gas pressure region, and is expected to be promising in the future.

FIG. 2 is a cross-sectional view schematically showing a plasma processing apparatus that generates plasma by electron cyclotron resonance excitation among the above-mentioned plasma processing apparatuses. In FIG. 2, reference numeral 11 denotes a plasma generation chamber.

The peripheral wall of the plasma generation chamber 11 has a double structure, in which a cooling water flow chamber 11a is formed, and a microwave inlet sealed with a quartz glass plate 11b is formed in the center of the upper wall. 11c, and a plasma extraction window 11d is formed at the center of the lower wall at a position facing the microwave introduction port 11c. One end of a waveguide 12 whose other end is connected to a microwave oscillator (not shown) is connected to the microwave introduction port 11c, and a sample chamber 13 is provided facing the plasma extraction window 11d. Further, an exciting coil 14 is disposed concentrically with the plasma generation chamber 11 and the waveguide 12 connected thereto so as to surround them over one end thereof.

On the other hand, a sample holder 17 is disposed in the sample chamber 13 at a position facing the plasma extraction window 11d, and a substrate S such as a wafer is mounted on the sample holder 17 by an electrostatic chuck (not shown). It is kept as possible. In the lower wall of the sample chamber 13, an exhaust port 13a connected to an exhaust device (not shown) is formed.

[0007] The entire upper wall excluding the side wall of the plasma generation chamber 11 and the microwave inlet 11c, the sample chamber 13
A cover 25 is disposed so as to cover substantially the entire inner wall of the sample table 17 and substantially the entire periphery of the sample table 17 except for the portion where the substrate S to be processed is placed and the bottom surface.

In the figure, reference numeral 11g denotes a plasma generation chamber 11;
13g represents a reaction gas supply system connected to the sample chamber 13, and 11g represents a reaction gas supply system connected to the sample chamber 13.
Reference numeral 1i denotes a cooling water supply system and a discharge system.

In the plasma processing apparatus configured as described above, after the inside of the plasma generation chamber 11 and the sample chamber 13 are set to a predetermined degree of vacuum, a required amount of gas is supplied into the plasma generation chamber 11 through a reaction gas supply system 11g. A gas is supplied so that a gas pressure is obtained, and a magnetic field is formed by the excitation coil 14 while the plasma generation chamber 11 is formed through the microwave introduction port 11c.
A microwave of, for example, 2.45 GHz is introduced thereinto, and the gas is resonantly excited using the plasma generation chamber 11 as a cavity resonator to generate plasma. The generated plasma is projected around the substrate S in the sample chamber 13 by a divergent magnetic field whose magnetic flux density decreases toward the sample chamber 13 formed by the exciting coil 14, and the surface of the substrate S in the sample chamber 13 is exposed. Is subjected to plasma treatment.

As shown in FIG. 2, most of the apparatus main body with which the plasma gas comes into contact is covered with the anti-adhesion cover 25 because a metal material such as SUS is used when the substrate S is subjected to plasma processing. A contaminant such as Cr or Fe diffuses from the inner wall or the like of the plasma processing apparatus and is attached to the substrate S to be processed, thereby preventing the substrate S from being contaminated by these heavy metals and the like. That's why.

Conversely, the anti-adhesion cover has a role of preventing reaction products and the like generated by the etching process and the like from adhering to the surrounding inner wall portion and peeling off to become particles and cause contamination. Also plays.

[0012]

As described above, in the above-described plasma processing apparatus, when performing the plasma processing, the target substrate S to be subjected to the plasma processing is made of metal or the like derived from surrounding materials. In order to prevent contamination, and to prevent the substrate S from being re-contaminated by reaction products and the like diffused and adhered to the surroundings by the plasma processing, the contamination around the substrate S is generated. The deposition-inhibiting cover 25 is provided in a portion likely to be damaged.

Conventionally, the characteristics required of the deposition-inhibiting cover 25 that plays such a role are that it is not easily corroded by a halogen-based gas used in a process such as etching, and is a source of contamination of the substrate S to be processed. It must be chemically stable and free from impurities so that it does not crack, it must be a material that has mechanical durability that does not cause cracks or the like even by heat or the corrosive gas atmosphere described above. The surface may not be damaged by the cleaning process or the like so that the anti-adhesion cover to which the product or the like has adhered can be cleaned.

As the anti-adhesion cover, a cover made of aluminum, SiO ₂ or the like has been conventionally used.

[0015] However, when using the aluminum plate as adhesion preventing cover, there is a problem that tends to contamination source to the target substrate S for adhesion preventing cover itself is not chemically stable, whereas the SiO ₂ as a material In the case where an anti-adhesion cover is used, the SiO ₂ plate is fragile, so that cracks and the like are apt to occur and there is a problem in durability. In addition, the anti-adhesion cover using SiO ₂ as a material is very expensive. was there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is chemically stable, somewhat hard, has almost no open pores due to the sealing treatment, and further contains almost no components other than the base material. Aluminum plate having an oxide film of high purity and its manufacturing method, and can be obtained relatively inexpensively, do not become a source of contamination of the sample, and can be used for a plasma processing apparatus having excellent durability and the like. It is intended to provide a wearing cover.

[0017]

In order to achieve the above object, an aluminum plate according to the present invention has a base material made of aluminum or an aluminum alloy having an oxide film made of a hydrate sealed on a surface of the base material. The thickness of the oxide film is 10
And the content of metal impurities other than the base material in the oxide film is 1 ppb or less.

Further, in the method of manufacturing an aluminum plate according to the present invention, an anodizing treatment is performed on a base material made of aluminum or an aluminum alloy to form an oxide film on the surface thereof.
In the method for producing an aluminum plate, in which the oxide film is subjected to a sealing treatment, the aluminum plate having the oxide film formed thereon is immersed in pure water and subjected to a sealing treatment at a temperature of 85 ° C. or less for 10 hours or more. And

Further, the anti-adhesion cover according to the present invention is characterized in that it is formed by using the aluminum plate and covers at least the inner wall surface of the reaction vessel constituting the plasma processing apparatus.

In the present invention, the aluminum plate is a generic term for an aluminum plate or an aluminum alloy plate having an oxide film made of a hydrate sealed to the surface of a base material made of aluminum or an aluminum alloy. I'm using Therefore, a normal aluminum plate is a plate made of aluminum alone.

First, a method for manufacturing an aluminum plate according to the present invention will be described.

The manufacturing process of the aluminum plate according to the present invention is roughly divided into four steps: a pre-cleaning process, an anodizing process, a cleaning process, and a sealing process.

First, in the pre-cleaning step, the surface of the aluminum plate is cleaned to remove impurities adhering to the surface. In this case, depending on the degree of surface contamination, acid, alkali, solvent, or using a surfactant,
It is desirable to completely remove various stains present on the surface. As the aluminum plate, for example, JI
S. H4000 (A1050, A6061, A505
2) and the like are preferable, and as the aluminum alloy, those containing metals such as iron, silicon, and magnesium are preferable.

Next, the aluminum plate is anodized. In this anodizing step, a known anodizing method may be used, in which an oxide film having a hardness ranging from a normal hardness to a hard hardness is formed.

The oxide film having a hardness from normal hardness to hardness means an oxide film having a micro Vickers hardness of about 150 to 450. Further, in order to form an oxide film having the above hardness, the sulfuric acid concentration is 150 to 320 g / liter,
The aluminum plate was immersed in a solution having an aluminum concentration of 2 to 25 g / liter, and the temperature of the solution was set to -5 to +2.
While maintaining the temperature at about 2 ° C., the electrolysis voltage is set to 10 to 90 V, and the anode is applied to the aluminum plate for about 1 to 2 hours by a direct current including an AC component such that the electrolysis current becomes about 1.5 to 5 A / dm ^2. An oxidation treatment is performed.

In order to form a hard oxide film, an organic sulfonic acid or an organic carboxylic acid may be added so that the concentration thereof is about 5 to 15 g / liter so that the electric conductivity of the electrolytic solution is increased. .

Under the above-mentioned conditions, an open pore can be eliminated by a sealing treatment described later, and an oxide film which is hardly cracked when used as an aluminum plate in various applications. The conditions of the anodizing treatment that can be performed are as follows. Particularly, at a temperature of 5 to 18 ° C. and an aluminum concentration of 7 g / liter or less, a specified power supply is used.
Electrolysis at 2V is preferred.

After the anodizing process, a cleaning process is performed. This cleaning treatment is performed to diffuse components in the electrolytic solution adhering to the surface and the inside of the open pores and other metal impurities contained in the aluminum plate into the solution.

For this reason, the purity of the washing water is preferably high purity of semi-pure water (electric conductivity of 125 kΩ or more) or more. Is preferred.

By this cleaning treatment, mainly anions such as sulfate groups and cations such as aluminum ions are removed from the anodic oxide film or from the surface, but impurities contained in the base metal aluminum metal itself are removed. For example, Fe, Si, etc., and impurities contained in the aluminum alloy itself, for example, Fe, Si, Cu, etc., are also removed to a considerable extent. Therefore, the concentration of metal impurities other than the base material in the anodic oxide film in this cleaning treatment is 1 ppb or less in total.

The surface of the aluminum plate has a hardness ranging from normal hardness to hardness by the anodizing treatment and the washing treatment, has a thickness of about 10 to 150 μm, and has a diameter of open pores of 5 μm.
About 0 to 130 °, and the density of open pores is 5 × 10 ⁸ to 70
An oxide film of about × 10 ⁸ / cm ² is formed.

The oxide film is a relatively dense barrier-type oxide film (hereinafter, referred to as a barrier layer) formed immediately on the surface of aluminum metal and a large number of apertures formed on the barrier layer. It has a double structure with a porous oxide film having pores (hereinafter, referred to as a porous layer),
The barrier layer is an alumina hydrate such as Al (OH) ₃ ;
The porous layer is composed of Al ₂ O ₃ .nH ₂ O (n = 1 to 3) alumina hydrate.

Since the oxide film obtained by the anodic oxidation treatment has a large number of open pores on the surface, if the oxide film is used as it is as a cover for a plasma treatment apparatus as it is, for example, the cracks caused by the porous layer And the like easily occur, and the reaction gas and the like easily reach the aluminum metal surface through the open pores, so that corrosion and the like easily progress,
These causes may cause inconvenience such as contamination of the sample to be subjected to the plasma processing.

Therefore, in order to eliminate these open pores and to form an oxide film which does not crack during the plasma treatment, it is necessary to perform a sealing treatment described below.

Usually, in this sealing treatment step, the sealing treatment is performed using high-temperature hot water, steam, or the like. Is easily expanded due to the expansion of cracks, and cracks and the like easily occur when exposed to an environment such as high temperature. Sealing is performed by filling the open pores with metal using nickel acetate or the like.However, since the metal is filled inside the open pores, in an environment such as a high temperature, the metal cannot be sealed. It becomes easy to diffuse from the oxide film.

In the present invention, in consideration of these points, the aluminum plate is heated at 85 ° C. or lower, preferably 40 to 8 ° C.
It is immersed in pure water (electric conductivity: 1 MΩ or more) at a temperature of 5 ° C., and sealed for 10 hours or more, preferably about 10 to 30 hours.

At this time, the lower the temperature of the pure water for performing the sealing treatment, the longer the immersion needs to be for soaking the pure water.
At about 5 ° C, it is sufficient to soak for about 10 hours.
When the temperature is lowered to about 0 ° C., it is necessary to soak for about 30 hours. Under these conditions, by performing the treatment at about 75 ° C. for about 13 hours, the sealing state is the best, the generation of distortion and the like is small, and a hard film is formed. By performing the sealing treatment at a low temperature for a long time as described above, an oxide film in which the pores have almost disappeared without any distortion due to gentle expansion accompanying the change of the hydrate is formed. No cracks or the like occur in the oxide film.

By immersing in pure water for a long time as described above, various impurity ions diffuse from the anodic oxide film into the solution as in the case of the cleaning process, and the oxide film is formed. Higher purity.

When the base material is aluminum, the oxide film obtained by the above method has a boehmite layer of 25 to 75 wt.
%, About 75% to 25% by weight of a bayerite layer, and a density of 2.62 to 2.75 g / cm ³ , resulting in an oxide film having almost no open pores on the surface. The purity of the oxide film is extremely high, with the content of metals other than the base material being 1 ppb or less, and the hardness of the oxide film is 350 to Vickers hardness.
It becomes a hard oxide film with about 450. The thickness of the oxide film is 10 to 150 μm, but the thickness is preferably 50 to 76 μm in order to obtain an oxide film having the above-described characteristics.

The aluminum plate manufactured by the above method has various excellent properties and can be used for various applications. In particular, it is preferably used as a protective cover for the plasma processing apparatus described above. be able to.

Next, the anti-adhesion cover according to the present invention will be described.

An example of a plasma processing apparatus using the deposition-inhibiting cover according to the present invention and the role of a general deposition-inhibiting cover have been described in detail in the section of "Prior Art", and thus the description thereof will be omitted. The description will focus on the characteristics and manufacturing method of the anti-adhesion cover according to the present invention.

The anti-adhesion cover according to the present invention is manufactured by using the above-mentioned aluminum plate according to the present invention and combining it with several aluminum plates so as to form the anti-adhesion cover.

It is desirable that the individual aluminum plates constituting the deposition-inhibiting cover be processed into a predetermined shape before the above-mentioned aluminum plate is manufactured, so that the aluminum plates are combined to form the deposition-inhibiting cover. .

Therefore, several aluminum plates of a predetermined size usually manufactured by the method of the present invention are assembled using metal fittings, bolts and the like, and attached to the inner wall or the like of the microwave plasma processing apparatus. Thereby, an anti-adhesion cover having a predetermined shape can be manufactured. Bolts used for assembling the anti-adhesive cover, metal fittings for assembling, and the like are naturally examined for their material so as not to become a source of contamination, and it is desirable that a surface that comes into contact with the plasma gas be subjected to a special coating treatment.

In a microwave plasma processing apparatus, for example, when a process such as CVD is performed, a corrosive gas containing chlorine, fluorine or the like may be used. Since it is covered with a stable and dense oxide film, corrosion by the gas hardly occurs. In addition, when performing the sealing treatment, since the treatment is performed at a low temperature for a long time, no distortion is generated in the oxide film, and the oxide film is cracked due to heat or electromagnetic influence of the generated plasma. Does not occur and is extremely excellent in durability.

As a result, when the plasma processing is performed using the plasma processing apparatus provided with the anti-adhesion cover according to the present invention, the target substrate to be subjected to the plasma processing is not contaminated by the anti-adhesion cover, Various plasma treatments can be favorably performed. In addition, not only can the anti-adhesion cover be used for a long period of time, but also if the anti-adhesion cover is contaminated, cleaning and the like can be easily performed.

The anti-adhesion cover according to the present invention can be used in various plasma processing apparatuses described in the section of "Prior Art", and can also be used in a so-called parallel plate type plasma processing apparatus.

[0049]

According to the aluminum plate of the present invention, a base material made of aluminum or an aluminum alloy has an oxide film made of a hydrate sealed on the surface, and the oxide film has a thickness of 10 to 150 μm. Since the content of metal impurities other than the base material in the oxide film is 1 ppb or less,
The oxide film has almost no open pores, is chemically stable, has excellent corrosion resistance, has high purity, and is exposed to a severe environment such as a high temperature. Does not spread. Therefore, the aluminum plate is suitably used for a deposition prevention cover of a plasma processing apparatus.

Further, in the method of manufacturing an aluminum plate according to the present invention, a base material made of aluminum or an aluminum alloy is subjected to anodizing treatment to form an oxide film on the surface thereof.
In the method for manufacturing an aluminum plate in which the oxide film is subjected to sealing treatment, the aluminum plate on which the oxide film is formed is immersed in pure water and subjected to sealing treatment at a temperature of 85 ° C. or less for 10 hours or more. The surface of the plate has almost no open pores, is chemically stable, has excellent corrosion resistance, and is formed of a hard, high-purity oxide film containing no material other than the base metal. Therefore, the aluminum plate is suitably used for a deposition prevention cover of a plasma processing apparatus.

Further, the anti-adhesion cover according to the present invention is formed by using the aluminum plate, and covers at least the inner wall surface of the reaction vessel constituting the plasma processing apparatus. It has no pores, is excellent in corrosion resistance, and has a high-purity oxide film. Therefore, corrosion of the deposition-inhibiting cover by the gas used for the plasma processing is unlikely to occur. Further, the anti-adhesion cover is subjected to a sealing treatment, so that the oxide film is hardly cracked or the like due to the heat or electromagnetic influence of the generated plasma, and is extremely excellent in durability.

As a result, when the plasma processing is performed using the plasma processing apparatus provided with the anti-adhesion cover according to the present invention, the substrate to be processed and the like are not contaminated by the anti-adhesion cover. Various plasma treatments can be performed satisfactorily.

[0053]

Examples and Comparative Examples Examples of the method for manufacturing an aluminum plate according to the present invention will be described below.

First, JIS. H4
000 (A1050), using an aluminum plate with an outer diameter (φ) of 480 mm, a length of 500 mm, and a thickness of 3 mm, degreased at a concentration of a neutral detergent of 5 ± 2%, 65 ° C. for 3 minutes, and then A sample that had been washed with water was used as a sample.

Next, the sulfuric acid concentration was 320 g / l, the aluminum concentration was 7 g / l, and the organic acid was 100 g / l.
The sample was immersed in 1 liter of the electrolytic solution, and a voltage was applied such that the temperature of the electrolytic cell + 2 ° C., the DC component of the electrolytic current was 3.0 A / dm ² , and the AC component was 1.0 A / dm ² .
The aluminum plate was anodized for about 60 minutes.

After the anodizing treatment was completed, the aluminum plate was washed with fresh quasi-pure water a total of three times each time to wash and remove impurities such as sulfate groups and metal ions.

After the completion of the washing treatment, the sample was heated to 70 ° C.
Was immersed in a liquid using pure water, and sealed for 13 hours while stirring. Thereafter, the obtained aluminum plate was dried to complete the production of the aluminum plate.

Next, various characteristics of the oxide film on the surface of the aluminum plate obtained by the above manufacturing method were examined.

First, when the thickness of the oxide film was measured using a scanning electron microscope (SEM), the thickness was 40 to 55 μm, and the number of open pores existing on the surface of the oxide film was 5 × 10 ^8.
少 な く 7 × 10 ⁸ / cm ² , which was mostly sealed.

Next, when the hardness of the oxide film was measured,
A hard coating with a Vickers hardness of about 350 to 450 is formed, and an X-ray microanalyzer (EPM
When the purity in the oxide film was measured using A), Mg
Is contained at about 0.1 ppb.
Although it was confirmed that u was contained, its content was below the detection limit, and no other elements could be detected.

Next, several aluminum plates having a predetermined shape manufactured by the above-described manufacturing method are used, and assembled into a shape of a deposition-preventing cover by using metal fittings and bolts for assembly. It was attached to the sample stage.

FIG. 1 is a cross-sectional view schematically showing a microwave plasma processing apparatus equipped with a deposition prevention cover according to the embodiment. Except that the deposition-inhibiting cover 15 is formed from the aluminum plate according to the above embodiment, the configuration is exactly the same as that of the microwave plasma processing apparatus described in the section of “Prior Art”, and the description thereof will be omitted here. Omitted.

Using a microwave plasma processing apparatus equipped with the deposition-inhibiting cover 15 according to this embodiment, an etching process was performed on the substrate S made of a Si wafer having a 1 μm oxide film formed thereon.

When performing the etching treatment, C ₄ H ₈ : 25 sccm and O ₂ : 13 scc are used as an etching gas.
m, the pressure is 1 mTorr, the microwave power is 1.3 kW, and the high frequency applied to the sample holder is 400 kHz.
Etching was performed under the conditions of z and an etching time of 3 minutes.

The substrate S to be processed is etched under the above conditions, and the substrate S after each etching is processed.
The content of metal impurities on the surface was measured, and the surface condition of the anti-adhesion cover after the above treatment was completed was observed by SEM.

As a result, the concentration of metal on the surface of the substrate S to be processed can be suppressed to a small amount of contamination sufficient for use as a semiconductor device. No cracking or corrosion was observed.

[0067]

As described above in detail, the aluminum plate according to the present invention has an oxide film made of a hydrate that has been sealed on the surface of a base material made of aluminum or an aluminum alloy. The thickness of the oxide film is 10 to 150 μm
Since the content of metal impurities other than the base material in the oxide film is 1 ppb or less, the oxide film has almost no open pores, is chemically stable, and has excellent corrosion resistance.
It is of high purity and can prevent metals and the like from diffusing from the aluminum plate to the surroundings even when exposed to a severe environment such as high temperature. Therefore, the aluminum plate can be suitably used for a deposition prevention cover of a plasma processing apparatus.

In the method for manufacturing an aluminum plate according to the present invention, a base material made of aluminum or an aluminum alloy is subjected to anodizing treatment to form an oxide film on the surface thereof, and the oxide film is subjected to sealing treatment. In the method for manufacturing an aluminum plate to be applied, the aluminum plate on which the oxide film is formed is immersed in pure water and subjected to a sealing treatment at a temperature of 85 ° C. or less for 10 hours or more, so that open pores are formed on the surface of the aluminum plate. Almost no, it is chemically stable, has excellent corrosion resistance, and can form a hard, high-purity oxide film containing no metal other than the base material. Therefore, the aluminum plate manufactured by the above method can be suitably used for a deposition prevention cover of a plasma processing apparatus.

In the anti-wear cover according to the present invention,
Since it is formed using the aluminum plate and covers at least the inner wall surface of the reaction vessel constituting the plasma processing apparatus, the surface is chemically stable and has few open pores,
It has excellent corrosion resistance and a high-purity oxide film. Therefore, corrosion of the deposition-inhibiting cover by the gas used for the plasma processing is unlikely to occur. Further, the anti-adhesion cover has been subjected to a sealing treatment, due to the heat and electromagnetic effects of the generated plasma, the oxide film is less likely to crack or the like,
Extremely durable.

As a result, when the plasma processing is performed using the plasma processing apparatus provided with the anti-adhesion cover according to the present invention, the substrate to be processed by the plasma processing is not contaminated by the anti-adhesion cover. Various plasma treatments can be performed well. In addition, the above-mentioned anti-adhesion cover can be used for a long time, and when the anti-adhesion cover is contaminated, a cleaning process or the like can be easily performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a microwave plasma processing apparatus using a deposition-inhibiting cover according to an embodiment.

FIG. 2 is a cross-sectional view schematically showing a conventional microwave plasma processing apparatus.

[Explanation of symbols]

 15 Protective cover

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-34291 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C25D 11/00-11/24 C23F 4 / 00

Claims (3)

(57) [Claims] 1. A base material made of aluminum or an aluminum alloy, the surface of which has an oxide film made of a hydrate that has been subjected to a sealing treatment, the oxide film has a thickness of 10 to 150 μm, and the base material in the oxide film has a thickness of 10 to 150 μm. Metal impurities other than 1p
An aluminum plate, which is not more than pb. 2. A method for producing an aluminum plate, comprising: subjecting a base material made of aluminum or an aluminum alloy to anodizing treatment to form an oxide film on the surface thereof and sealing the oxide film to form an aluminum plate. A method for producing an aluminum plate, comprising immersing the treated aluminum plate in pure water and performing a sealing treatment at a temperature of 85 ° C. or less for 10 hours or more. 3. An anti-adhesive cover made of the aluminum plate according to claim 1 and covering at least an inner wall surface of a reaction vessel constituting a plasma processing apparatus.