JP2002110547A - Plasma treating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma treating apparatus having excellent productivity, by improving machining properties, mechanical strength, plasma resistance and maintainability of a vacuum bolt. SOLUTION: The plasma treating apparatus supplies reactive gas and an electric power to a vacuum chamber and treats board by means of a chemical reaction of the gas. The apparatus further thermally sprays a substance having a plasma resistance to a member 1 exposed with a plasma treating chamber 3, and clamps the member 3 by a bolt 7 formed with a plasma resistant film 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a plasma processing apparatus such as a plasma CVD apparatus and a dry etching apparatus used for manufacturing a semiconductor device or a liquid crystal display device.

[0002]

2. Description of the Related Art As a plasma processing apparatus used for manufacturing a semiconductor device and a liquid crystal display device, a plasma CV is generally used.
D apparatuses and dry etching apparatuses are known. These apparatuses have a vacuum chamber in which electrodes to which power is supplied are arranged, a substrate to be processed (a semiconductor wafer or a glass substrate) is charged into the vacuum chamber, and the substrate is heated as necessary, and a vacuum is applied. After reducing the pressure in the chamber, a reactive gas is introduced into the vacuum chamber, power is supplied to the electrodes, plasma is generated in the vacuum chamber, and a substance is deposited on the substrate by a chemical reaction. The etching or the process of altering the quality of the substance on the substrate or the substrate itself is performed.

At present, the most frequently used type is a capacitively coupled plasma processing apparatus. In this type of plasma processing apparatus, a pair of parallel plate electrodes are arranged in a vacuum chamber so as to face each other, high-frequency power is supplied to one of them, a substrate is held on the other electrode side, and plasma is generated between the electrodes. To process the substrate.

[0004] The present invention is not limited to the above-described structure, but may be applied to an apparatus having a structure for supplying power to an electrode for holding a substrate or a structure for supplying second power to an electrode for placing a substrate. Devices also exist.

In such a plasma processing apparatus, a plurality of vacuum bolts are used to form a process kit in a vacuum chamber. However, there is a problem of plasma resistance that the surface is corroded and the substrate is contaminated.

[0006] For this reason, the following performance is required for the vacuum bolt for plasma processing.

[0007] 1. Excellent mechanical strength that can be fixed with strong torque in order to be compatible with large equipment and to be able to use at high temperatures. 2. Minimize corrosion, deformation, and alteration even when the bolt surface is exposed to plasma or reactive gas (it has plasma resistance and corrosion resistance to reactive gas). 3. Deterioration is minimal during prolonged use or multiple desorptions.

Conventional vacuum bolts include Ni-based corrosion-resistant alloys such as Inconel and Hastelloy, surface treatments (Ni plating, oxidation treatment, fluoridation treatment, and alumite treatment) on the surface of the vacuum bolts, and the material of the bolts is ceramics. The technology is known.

[0009]

However, the above-mentioned conventional vacuum bolt has the following problems.

[0010] 1. Ni such as Inconel and Hastelloy
When a process involving hydrogen is performed at a high temperature (150 ° C. or higher) on a bolt made of a corrosion-resistant alloy, an oxide layer is destroyed on the metal surface in contact with the activated gas, and powdery Ni- or Fe-based foreign matter is removed. Easy to occur. 2. Ni-plated bolts in surface treatment are not resistant to ammonia and HF and have high temperatures (150 ° C or higher)
Turns black in fluorine atmosphere. 3. Alumite-treated bolts for surface treatment use aluminum as the base material with good workability, but have relatively low mechanical strength, especially when used in large equipment or when used in a high-temperature atmosphere. There is a possibility that deformation is likely to occur due to the use of. Also, aluminum is weak to chlorine atmosphere, so it is often used with alumite treatment especially in dry etching equipment. However, this alumite is etched by plasma over a long period of use and its thickness decreases, so regeneration treatment is essential. It is. 4. Ceramic bolts have good plasma resistance but low mechanical strength, and have problems when fixed with strong torque, and also have problems with workability.

The present invention has been made in view of the above circumstances, and provides a plasma processing apparatus which has improved workability, mechanical strength, plasma resistance, and maintainability, and is excellent in productivity.

[0012]

SUMMARY OF THE INVENTION The present invention relates to a plasma processing apparatus for supplying a reactive gas and electric power to a vacuum chamber and processing a substrate by a chemical reaction of the reactive gas. The present invention relates to a plasma processing apparatus in which a plasma-resistant material is sprayed to form a plasma-resistant film.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

As described above, the plasma processing apparatus has a vacuum chamber for processing a substrate, and a vacuum bolt for plasma processing in a vacuum chamber is used to form a process kit in the vacuum chamber. The following performance is required for the processing vacuum bolt.

1. Excellent mechanical strength that can be fixed with strong torque in order to be compatible with large equipment and to be able to use at high temperatures. 2. Minimize corrosion, deformation, and alteration even when the bolt surface is exposed to plasma or reactive gas (it has plasma resistance and corrosion resistance to reactive gas). 3. Deterioration is minimal during prolonged use or multiple desorptions.

Therefore, in the present invention, in order to satisfy the above-mentioned requirements (1) and (2), a corrosion-resistant alloy is used for the bolt, and a plasma-resistant material is sprayed to form a plasma-resistant film.
Since the plasma resistant film does not have mechanical strength such as friction and peeling, the portion where the attachment and detachment are repeated to satisfy the requirement of the above 3 is performed on the surface where friction occurs when attaching and detaching the bolt or the contact surface with the tool. Fit the bolt cover covering the head to the bolt head. The bolt itself is selected with priority on mechanical strength,
The material of the bolt cover is selected by giving priority to plasma resistance and corrosion resistance, and a material that generates minimum dust even when friction occurs is selected.

This will be described more specifically with reference to FIGS.

In the figure, reference numerals 1 and 2 denote process kits, and the process kit 1 is exposed to the plasma processing chamber 3. The process kits 1 and 2 are fixed by vacuum bolts 4 from the plasma processing chamber 3 side.

The bolt body 7 includes a screw portion 7c screwed into the screw hole 5 of the process kit 2, a screw neck portion 7b inserted through the through hole 6 of the process kit 1, and a bolt head 7a, excluding the screw portion 7c. A plasma-resistant material is sprayed on the surface to form a plasma-resistant film 8. The bolt body 7 is a refractory metal and a corrosion-resistant metal, for example, Inconel or Hastelloy is used.
Are formed by performing a surface treatment such as aluminum alloy spraying or Ni alloy spraying such as Hastelloy.

A bolt cover 9 is fitted to the bolt head 7a.

The bolt cover 9 has a hexagonal outer diameter similar to the bolt head 7a and a fitting hole 9a, and the screw neck 7b passes through the bottom of the fitting hole 9a. A relief 9b is formed at the corner of the fitting hole 9a so that the top of the bolt head 7a does not interfere with the corner of the fitting hole 9a due to a processing error. Therefore, the bolt cover 9 covers the peripheral surface of the bolt head 7a to which a tightening tool (not shown) is fitted, and the bottom surface having friction with the process kit 1. The bolt cover 9 is made of plasma-resistant aluminum or ceramic.

By using the vacuum bolt for plasma treatment in a vacuum chamber, the bolt body 7 has a sufficient mechanical strength, so that a strong tightening force required for assembling the process kits 1 and 2 can be obtained. Further, since the plasma resistant film 8 is formed on a portion of the bolt body 7 exposed to the plasma processing chamber 3, the bolt has resistance to plasma and does not cause corrosion. Incidentally, the plasma resistant film 8 is easily peeled off by a mechanical external force such as scratching or friction. The bolt cover 9 protects the plasma resistant film 8 on the bolt head 7a.

When assembling and disassembling the process kits 1 and 2, the vacuum bolt 4 is attached and detached. At this time, the tool comes into contact with the bolt head 7a via the bolt cover 9 and the bolt head 7a Rubs against the process kit 1 via the bolt cover 9 so that no external force such as friction or compression acts on the plasma-resistant film 8 and the plasma-resistant film 8 is not damaged. Even if 4 is used repeatedly, corrosion by plasma does not occur.

When the vacuum bolt 4 is not frequently attached or detached or removed, or when a new vacuum bolt 4 is used, the bolt cover 9 is not necessarily used.

The bolt cover 9 may be used only at the time of attachment and detachment. In this case, the shape of the bolt cover 9 is a hexagonal cylinder.

As described above, according to the present invention, a material having mechanical strength is used for the base material of the vacuum bolt, and the surface in contact with the plasma is subjected to a plasma-resistant surface treatment to reduce mechanical friction and the like. The affected surface is to be fitted with a cover,
The processability, mechanical strength, corrosion resistance, and maintainability are improved, and the processing apparatus is excellent in productivity.

[0027]

As described above, according to the present invention, in a plasma processing apparatus for supplying a reactive gas and electric power to a vacuum chamber and processing a substrate by a chemical reaction of the reactive gas, the apparatus is exposed to the plasma processing chamber. The material to be treated is fixed by bolts that have a plasma-resistant film formed by spraying a plasma-resistant material, so the surface corrodes, the corroded material corrodes the substrate to be processed, contaminates the substrate, and reduces the processing quality. Alternatively, since the occurrence of product defects can be prevented, an excellent effect of improving the processing quality and the yield, and improving the productivity can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 2 is a plan view of a main part of the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Process kit 2 Process kit 3 Plasma processing chamber 4 Vacuum bolt 5 Screw hole 6 Through hole 7 Bolt body 8 Plasma resistant film 9 Bolt cover

Claims (1)

[Claims] In a plasma processing apparatus for supplying a reactive gas and electric power to a vacuum chamber and processing a substrate by a chemical reaction of the reactive gas, a member exposed to the plasma processing chamber is sprayed with a substance having plasma resistance. A plasma processing apparatus characterized by being fixed by bolts having a plasma resistant film formed thereon.