JPH10298685A - Electrode parts for semiconductor producing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain electrode parts for producing semiconductors composed of a metal-ceramics composite material excellent in heat resistance by infiltrating the molten metal of an Al allay into a preform made of ceramics using AlN powder having specified particle size as the raw material and executing solidification. SOLUTION: Fine pulverious AlN having 1 to 150 μm average particle size is added with a binder and water to form into the shape of slurry. This slurry is poured into a mold and is applied with vibration to settle solids in the slurry, the supernatant is removed, and compacting is executed. This compacted body is frozened in the mold and is released from the mold and is dried and sintered to form into a preform. An Al alloy of Al-Mg or the like is placed on the preform, and heating is executed to the melting temp. of the At alloy or above in a nitrogen gas atmosphere to infiltrate the Al alloy into the preform under no pressure. It is impregnated at 50 to 80 vol.% powder filling ratio to obtain a composite material used for an electrode for a semiconductor producing device composed of the metal-ceramics material. The electrode material excellent in thermal conductivity, degassing properties and plasma resistance can stably be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode part for a semiconductor manufacturing apparatus, and more particularly to an electrode part for a semiconductor manufacturing apparatus using a metal-ceramic composite material.

[0002]

2. Description of the Related Art In recent years, with the rapid development of electronic devices such as computers, the core semiconductor chips have been required to have higher integration and lower cost. There is a need for continuous improvement. In particular, with respect to apparatuses such as plasma CVD and etching, the number of cases in which a wafer is heated and processed is increasing in order to improve the yield and processing speed of semiconductors.

[0003] The electrode parts used in the plasma CVD apparatus and the like are currently A6061 (Al-) because they have good degassing properties and can easily obtain a high vacuum in addition to good conductivity and thermal conductivity. Many parts in which an anodic oxide film treatment is applied to an aluminum alloy such as (Mg-Si-Cu) are used. This component also has an excellent property of being hardly corroded by a plasma gas containing a fluorine-based gas.

[0004]

However, a component obtained by subjecting the above aluminum alloy to the anodic oxidation coating treatment has a low melting point, so that it has poor heat resistance and is easily softened and deformed even at a temperature of about 300 ° C. was there. Therefore, there has been a problem that the life of the components is shortened by repeating the heat treatment of the wafer, and the running cost required for the replacement is greatly increased.

The present invention has been made in view of the above-mentioned problems of the electrode component for a semiconductor manufacturing apparatus, and has as its object to provide an electrode part for a semiconductor manufacturing apparatus with improved heat resistance.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, a preform formed of AlN powder has been used as a main component in an electrode part for semiconductor manufacturing equipment. Metal impregnated with
The present inventors have found that the use of a ceramic composite material can provide an electrode component having excellent heat resistance, and have completed the present invention.

That is, according to the present invention, the average particle size is 1 to 150 μm.
A preform formed of AlN powder of the above is impregnated with a metal containing aluminum as a main component and has a powder filling rate of 50 to 8
The gist of the present invention is to provide an electrode part for a semiconductor manufacturing apparatus, which is made of a metal-ceramic composite material of 0 vol%. This will be described in more detail below.

As described above, an electrode component for a semiconductor manufacturing apparatus is made of a metal-ceramic composite material in which a metal mainly composed of aluminum is permeated into a preform formed of AlN powder. This composite material has been developed as a material that has both the high toughness and high thermal conductivity of metal and the high rigidity and low thermal expansion of ceramics. It is based on the fact that it has enough. This composite material is excellent in heat resistance, of course, since ceramic powder is added to the metal.

The reason why the metal in the composite material is an aluminum alloy is that it is excellent in conductivity, heat conductivity, degassing property, plasma resistance and the like, as described above. The reason why the ceramic powder is AlN powder is that it has excellent plasma conductivity and good thermal conductivity. Ceramic powders other than AlN can be used. For example, Al ₂ O ₃ powder is inferior in terms of poor thermal conductivity, and SiC powder is inferior in plasma resistance.
Powders other than N are not preferable, and among ceramic powders, this AlN powder is the most suitable.

When the amount of AlN powder is increased, the packing of the powder becomes denser, so that the resistance to deformation due to thermal softening is increased and the heat resistance is improved.
%, The effect on heat resistance improvement is not sufficient,
If it is higher than 80% by volume, it becomes difficult to fill, and the electric resistance of the electrode component becomes too high. Therefore, the powder filling rate is preferably 50 to 80 vol%, and when the powder filling rate is about 70 vol%, it is particularly preferable because the filling is easy and the preform is easy to handle. The average particle size of the AlN powder is preferably from 1 to 150 μm, and if it is smaller than 1 μm, penetration of aluminum becomes difficult, and if it is coarser than 150 μm, formation of a preform becomes difficult, and production of electrode parts becomes difficult.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a method for producing the above-mentioned metal-ceramic composite material, methods such as powder metallurgy, high-pressure casting, and vacuum casting have been conventionally known. However, these methods cannot increase the content of the ceramic powder,
In addition, none of them was satisfactory because a large-sized pressurizing device was required, near-net molding was difficult, and the cost was high.

Therefore, recently, as a manufacturing method for solving the above problem, a non-pressurized metal infiltration method developed by Rankside Co., USA has attracted attention. This method uses SiC or Al ₂
This is a method in which an aluminum ingot is brought into contact with a preform formed of a ceramic powder such as O ₃ and heated to 700 to 900 ° C. in an N ₂ atmosphere to impregnate the preform with a molten aluminum alloy. This is to improve the wettability of the molten alloy to ceramic powder by utilizing the chemical reaction of Mg contained in the alloy, and the molten alloy permeates the preform without applying pressure.

In this method, the content of the ceramic powder is as wide as 30 to 85 vol% and can be changed to a high range.
vol% can be easily achieved. Further, since the preform manufactured by this method has a high degree of freedom in the shape, a considerably complicated shape can be formed by the near net. As described above, this method does not require a pressurizing device, can increase the content of ceramic powder, and enables near-net molding. Therefore, this method is an excellent method for solving the above-described problems including costs. is there.

From the above, since the manufacturing method by the non-pressurized metal infiltration method is most suitable for manufacturing the electrode part for a semiconductor manufacturing apparatus of the present invention, the electrode part of the present invention is manufactured by this method. An embodiment will be described below. First, an AlN powder having an average particle size of 1 to 150 μm is prepared. Use this powder alone or two powders with different average particle sizes.
You may mix and use more than one type.

A preform is formed from the prepared ceramic powder. The forming method may be any method such as sedimentation molding, injection molding, and other CIP molding. In short, any method can be used as long as it can maintain a shape until the penetration of the aluminum alloy is completed and can form a preform that does not inhibit the penetration. However, when water is used as a dispersion medium for forming a preform, it cannot be used because the AlN powder reacts with water. In this case, for example, AlN
The surface needs to be coated. The coated silica is reduced during the infiltration of the aluminum alloy and incorporated into the aluminum alloy as Si metal, so that there is no adverse effect.

Among the methods of forming preforms, the following describes an example of sedimentation molding which is most frequently used by the present inventors. First, a binder and water are added to prepared AlN powder and mixed to form a slurry. The slurry is poured into a mold of rubber or the like and vibrated to settle solids, and the supernatant is removed and molded. The obtained molded body is frozen in a mold, the frozen molded body is released, dried, and sintered to form a preform. 700 ~
By infiltrating a metal mainly composed of aluminum at a temperature of 900 ° C. without applying pressure, a composite material used for an electrode for a semiconductor manufacturing apparatus can be obtained.

When an electrode part for a semiconductor manufacturing apparatus is manufactured by the above method, an electrode part having excellent heat resistance can be obtained.

[0018]

EXAMPLES Hereinafter, the present invention will be described in more detail by giving specific examples of the present invention.

(Example) (1) Formation of Preform Silica-coated AlN powder (manufactured by Dow Chemical Co., Ltd.) having an average particle diameter of 16 μm was used as a ceramic powder, and a colloidal silica liquid was used as a binder for the powder. Was added in an amount of 2 wt%, ion-exchanged water was added to the mixture in an amount of 24 wt%, and the mixture was mixed for 8 hours in a pot mill containing no medium. Assuming an 8 inch wafer susceptor (electrode part for plasma CVD discharge), the obtained slurry was poured into a disk-shaped silicone rubber mold of φ210 × t6 mm, and vibrated to settle the solid content. Remove water and leave in rubber mold -30
After cooling to ° C., a frozen product was obtained. The obtained frozen product was left still overnight, demolded, and fired at 1050 ° C. for 12 hours to form a preform.

(2) Electrode parts for semiconductor manufacturing equipment (metal
Preparation of Ceramic Composite Material) An aluminum alloy having an Al-7Mg composition 2.5 times the weight of the preform is placed on the formed preform, and is subjected to non-pressure infiltration at 810 ° C. for 12 hours in a nitrogen atmosphere. Then, the mixture was cooled at 100 ° C./hr to produce a metal-ceramic composite material used for an electrode component for a semiconductor manufacturing apparatus.

(3) Evaluation A test piece was cut out from the formed preform, and the bulk specific gravity was measured by the Archimedes method to determine the powder filling rate of the preform. As a result, it was 70 vol%. Further, the specific resistance of the obtained composite material was measured by a four-terminal method. As a result, it was 40 × 10 ⁻⁸ Ω · m at room temperature. This number is
2-3 × 10 ^-8 which is the specific resistance of general aluminum alloy
Although it is almost one digit lower than Ω · m, it does not hinder practical use and has a sufficient function as an electrode component. Further, the composite material was placed in an electric furnace at 600 ° C. for 10 hours to examine heat resistance. As a result, there was no deformation. this is,
Considering that the melting point of A6061 (aluminum alloy), which is the material of the conventional electrode component, is 550 to 600 ° C., it can be said that the heat resistance is greatly improved. Furthermore, a JIS R using a test piece cut out of the composite material was used.
The thermal conductivity was measured by the laser flash method in accordance with 1611 (Test method for thermal diffusivity, specific heat capacity and thermal conductivity of fine ceramics by laser flash method). As a result, it was 176 W / mK. This is pure A
Although it does not reach 240 W / mK of 1 metal, it is sufficiently comparable to 140 to 180 W / mK of general aluminum alloy. Other properties such as degassing property and plasma resistance are not measured. However, since these properties are replaced by better AlN powder, they do not worsen than conventional aluminum alloys alone.

[0022]

As described above, since the metal-ceramic composite material containing AlN powder is used in the electrode part for a semiconductor manufacturing apparatus according to the present invention, the electrode part is excellent in heat resistance and heat conduction as compared with the conventional one. An electrode part having the same properties, degassing properties, and plasma resistance was also obtained. As a result, even if the heat treatment of the wafer is repeated, the running cost required for the replacement is expected to be greatly reduced.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomiwa Koyama 1-3-1-805 Ukima, Kita-ku, Tokyo

Claims (1)

[Claims] 1. A preform formed of AlN powder having an average particle size of 1 to 150 μm and made of a metal-ceramic composite material having a powder filling rate of 50 to 80 vol% by infiltrating a metal containing aluminum as a main component. An electrode component for a semiconductor manufacturing apparatus, comprising: