JP2001031484A - Corrosion-resistant composite member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a member having high resistances to halogen-based corrosive gases or plasmas thereof and suitable for a large-sized part by forming a corrosive film comprising a rare earth oxide in a specific proportion or above and constituting a site exposed to the halogen-based corrosive gases or plasmas thereof on a support having a coefficient of thermal expansion within a specific range and a specified value or below of dielectric loss. SOLUTION: The coefficient of thermal expansion of a support is 7×10-6 to 12×10-6 and the dielectric loss thereof is <=5×10-3. The content of a rare earth oxide in a corrosion-resistant film is >=50 wt.%. Y2O3, Dy2O3, Er2O3 and like are cited as the rare earth oxide and Y2O3 is preferred. When two or more components of oxides are contained, a compound oxide such as Y2O3-Al2O3 is preferably roentgenologically formed. The corrosion-resistant film is formed by a thermal spraying or a sputtering method. The support is preferably alumina, zirconia or the like. Thereby, cracking or peeling of a film due to a large difference in thermal expansion or a large dielectric loss is scarcely caused even when a large-sized part is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrosion-resistant composite member having high resistance to a halogen-based corrosive gas or a halogen gas plasma, which is suitable for a semiconductor device manufacturing process and a liquid crystal display device manufacturing process.

[0002]

2. Description of the Related Art Quartz glass and sintered ceramics are often used as members used in an environment having a high chemical corrosivity typified by a semiconductor device manufacturing process. Examples of such a member include a bell jar, a chamber, a susceptor, a clamp ring, a focus ring, and the like, which are used, for example, in a dry etching process using a highly corrosive halogen-based gas.

In the manufacturing process of semiconductor devices and liquid crystal display devices, the size of the substrate is increased from the viewpoint of cost reduction.
There is a demand for a liquid crystal display device substrate of a very large size of 1 m □, and accordingly, it is necessary to increase the size of a manufacturing apparatus.

[0004]

However, in the case of quartz glass which has been used in the past, it is inevitably limited to deal with large parts in terms of strength and rigidity. In addition, in the production of large parts of alumina ceramics, there is a problem of non-uniform structure represented by coarse pores. Particularly in an environment having high corrosiveness, these pores serve as a starting point of corrosion. Is concerned. In particular, sapphire is a material having high corrosion resistance, but this also has a limitation in handling large-sized components due to the problem of single crystal production size.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a corrosion-resistant composite member having high resistance to a halogen-based corrosive gas or a halogen gas plasma and suitable for large-sized parts.

[0006]

[MEANS FOR SOLVING THE PROBLEMS]
The present invention has a coefficient of thermal expansion of 7 × 10^-6~ 12 × 10
^-6And dielectric loss is 5 × 10^-3The following supports and above
And containing at least 50% by weight of rare earth oxides,
Exposed to gen-based corrosive gas or their plasma
Corrosion resistance characterized by having a corrosion resistant film constituting
A composite composite member is provided.

According to the present invention, the coefficient of thermal expansion is 7 × 10 ^−6.
~ 12 × 10 ^-6 which is relatively small and dielectric loss is 5 ×
Since a corrosion-resistant film containing 50% by weight or more of a rare-earth oxide is formed on a support having a size of 10 ⁻³ or less, and the corrosion-resistant film is formed as a portion exposed to a halogen-based corrosive gas or a plasma thereof, It has high resistance to halogen-based corrosive gas or halogen gas plasma, and even when it is large-sized, cracks and film peeling due to large thermal expansion difference and large dielectric loss hardly occur.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. The corrosion-resistant composite member of the present invention has a coefficient of thermal expansion of 7 × 1.
0 and ^-6 to 12 × ^{10 -6} in dielectric loss 5 × ^{10 -3} or less of a support, formed thereon, a rare earth oxide comprises 50 wt% or more,曝the halogen-based corrosive gas or their plasma And a corrosion-resistant film constituting a portion to be formed.

Material containing at least 50% by weight of rare earth oxide
Is resistant to halogen-based corrosive gases or their plasma.
The film made of such materials has high resistance to halo.
Exposed to gen-based corrosive gas or their plasma
Configure the rank. The amount of rare earth oxide is less than 50% by weight
If so, the corrosion resistance is insufficient. As rare earth oxides, Y
₂O₃, Dy₂O₃, Er₂O₃Etc.
You. Of these, Y₂O₃Is preferred. Corrosion resistant film
The rare earth oxide alone may be used, or other components may be used.
May be included. Also contains two or more oxides
In this case, it is preferable that the composite oxide is formed X-ray.
New As such a composite oxide, Y ₂O₃-Al
₂O₃Type is preferable, for example, YAlO₃, Y₄A
l₂O₉, Y₃Al₅O₁₂(Yttrium-Alumini
Um-garnet) and the like.

The method for forming the corrosion-resistant film may be a conventional film forming technique such as a thermal spraying method or a sputtering method, and is not particularly limited. In this case, it is desirable to sufficiently purge the raw materials and the film formation apparatus with water under reduced pressure. Thereby, a film having a low porosity can be formed.

The support for supporting the corrosion-resistant film has a coefficient of thermal expansion of 7 × 10 ^{−6 to} 12 × 10 ⁻⁶ and a dielectric loss of 5 × 10 ^−6.
The material is not particularly limited as long as it is ⁻³ or less, but a ceramic sintered body such as alumina and zirconia is preferable. The coefficient of thermal expansion of the support is 7 × 10 ^{−6 to} 12 × 10 ^−6.
The reason for this is that if it is out of this range, the film is likely to be peeled off or cracked due to a difference in thermal expansion from the corrosion-resistant film. Further, the reason why the dielectric loss of the support is set to 5 × 10 ⁻³ or less is that if the dielectric loss is more than 5 × 10 ⁻³ , the support generates heat when used in the GHz band, and peeling between the support and the corrosion-resistant film due to thermal stress is caused. This is because cracks are likely to occur.

The surface roughness of the support on which the corrosion-resistant film is formed is not particularly limited, but the center line average surface roughness Ra is 2 μm.
m or more. Thereby, a stronger bonding interface can be obtained. More preferably, Ra is 5 μm or more.

As described above, the coefficient of thermal expansion is 7 × 10 ⁻⁶ to
A corrosion resistant film containing at least 50% by weight of a rare earth oxide is formed on a support having a dielectric loss of 5 × 10 ⁻³ or less with a dielectric loss of 12 × 10 ⁻⁶ , and the film is exposed to a halogen-based corrosive gas or a plasma thereof. By configuring the exposed portion, a corrosion-resistant composite member having high resistance to halogen-based corrosive gas or halogen gas plasma and suitable for large-sized components can be obtained.

[0014]

Embodiments of the present invention will be described below. 99.9% pure yttrium oxide (Y ₂ O ₃ ) and 9 pure
Using 9.9% or more of aluminum oxide (Al ₂ O ₃ ), a corrosion-resistant film having a thickness of about 100 μm was formed on the surface of a 150 mm square ceramic support by a plasma spraying apparatus. 1 to 5 composite members were obtained. As the support, For 1, 2, 3, 5 the coefficient of thermal expansion is 8 × 10
^-6 / ° C aluminum oxide (alumina)
o. In No. 4, mullite having a coefficient of thermal expansion of 5 × 10 ⁻⁶ / ° C. was used. No. For the support of No. 5, the dielectric loss was increased by using a low-purity product containing a large amount of alkali metal as a raw material. Also,
As the corrosion resistant film, In 1 and 4, only Y ₂ O ₃ , N
o. Nos. 2 and 5, yttrium-aluminum-garnet (YAG); In No. _3, a mixture of Y ₂ O ₃ and Al ₂ O ₃ (Y ₂ O ₃ 30%) was used.

The composite member obtained in this manner is charged into a chamber of a parallel plate type RIE etching apparatus, and C
A corrosion test was performed using F ₄ + O ₂ plasma. At this time, a part of the polished surface was masked with a polyimide tape, and the etching rate was calculated by measuring the level difference between the portion with and without the mask. Table 1 shows these results.

As shown in Table 1, No. 1 was an embodiment within the scope of the present invention. 1 and 2 have an etching rate of 3 nm / m
in and a very small value, and no abnormality occurred at the interface between the support and the corrosion-resistant film.

On the other hand, the rare earth element (Y
No. ₂ O ₃ ) content was out of the range of the present invention. In No. 3, the etching rate was 8 nm / min, and the etching resistance (corrosion resistance) was reduced. In addition, the thermal expansion coefficient of the support was out of the range of the present invention. In No. 4, cracks were observed at the interface between the support and the corrosion-resistant film. Further, the dielectric loss of the support was out of the range of the present invention. In No. 5, cracks were similarly observed at the interface between the support and the corrosion-resistant film.

Next, a hemispherical dome-shaped product having an inner diameter of 400 mm made of aluminum oxide (alumina) was prepared, and this was used as a support, and YA was formed on the inner surface thereof by plasma spraying.
G layer, and A composite member evaluation product having the same combination as in Example 2 was obtained. This composite member evaluation product was set in a plasma chamber, and an etching test using plasma was performed in the same manner as in the above-described embodiment. As a result, the etching rate was 4 nm / min, and no abnormality was observed at the interface between the support and the corrosion-resistant film.

[0019]

[Table 1]

[0020]

As described above, according to the present invention,
Thermal expansion coefficient is 7 × 10^-6~ 12 × 10 ^-6The dielectric loss
5 × 10^-3The following support and the rare earth formed on it
Forming a corrosion-resistant film containing at least 50% by weight of oxides
The film is exposed to halogen-based corrosive gases or their plasma.
To form a part that is
High resistance to halogen gas plasma and large
A corrosion-resistant composite member suitable for a part can be obtained.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiromichi Otaki 3-5, Akimitsu, Izumi-ku, Sendai-shi, Miyagi Japan Inside the Ceratech headquarters plant of Japan Co., Ltd. (72) Yukio Kishi Meiji-san, Izumi-ku, Sendai-shi, Miyagi F-term (reference) in the Japan Ceratech headquarters factory at No. 5 Co., Ltd. 4K057 DD01 DE01 DE06 DE11 DM01 DM35 DM40 DN01 5F004 AA16 BB29

Claims (1)

[Claims] 1. The thermal expansion coefficient is from 7 × 10 ^{−6 to} 12 × 10
^-6 and a support having a dielectric loss of 5 × 10 ⁻³ or less and a corrosion resistance formed on the support and containing a rare earth oxide in an amount of 50% by weight or more and exposed to a halogen-based corrosive gas or a plasma thereof. A corrosion-resistant composite member having a film.