JP2000173936A - Member for thin film manufacture apparatus by vapor growth deposition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a deposition or an extraneous matter formed in each member or tool of an apparatus for manufacturing a thin film by vapor growth deposition, at high utility factor and high efficiency. SOLUTION: This member for a thin film manufacturing apparatus is composed of a glassy carbon material provided with properties of surface roughness Ra of 0.05 μm or less and porosity of 3% or less. Since reactivity with chlorine fluoride gas is restricted, it is possible to make to react with the chlorine fluoride gas at high temperatures without damaging a member, and it becomes possible to eliminate a deposit or an extraneous matter with high utility factor and efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film of amorphous silicon, GaAs,
an insulating film such as iO ₂ , Si ₃ N ₄ or TiC, S
The present invention relates to a member for an apparatus for producing a thin film such as a coating film such as iC by vapor deposition.

[0002]

2. Description of the Related Art Thin films such as ceramics are produced from a gas phase
The methods used are gas-phase chemical reaction (CVD) and physical vapor deposition.
(PVD method).
Subdivided into putter method, ion plating method, etc.
You. At present, for example, by the CVD method widely used, Si
_ThreeN_FourWhen forming a thin film, SiCl_FourSuch as halo
The heat of reduction of a silicon gemide compound and ammonia gas at high temperature
Dissolve and react to Si _ThreeN_FourBy precipitating
It forms a film. Therefore, the raw materials of the reaction system
By selecting the gas and atmosphere, for example, Al
_TwoO_ThreeOxides, nitrides and carbides such as TiN, TiC
Which film can be formed.

However, when a thin film is formed by this vapor deposition, the thin film is formed on the exposed surface of each member or jig of the thin film forming apparatus other than the target substrate surface. After the operation for a long time, a large amount of the reaction product accumulates on or adheres to the apparatus members and the jig surface. Therefore, it is necessary to appropriately remove these deposits and deposits for cleaning.

[0004] As a removing method, a method of chemically decomposing, for example, a method of washing with a strong acid or a strong alkali,
Alternatively, there is a method of mechanical polishing, etc., but it is not enough to efficiently remove deposits and deposits. Also C
There is also a method of removing in a plasma of a fluoride such as F ₄ , SF ₆ , NF _3, etc. However, when the equipment members and jigs are made of a carbonaceous material, the fluorine radicals react with the carbon material. There is a difficulty to be damaged.

[0005] In order to solve these difficulties, 100-
ClF, ClF ₃ , ClF ₅ within a temperature range of 350 ° C.
A method of cleaning a carbon material with a chlorine fluoride gas, comprising contacting a chlorine material containing at least one of them with a carbon material (JP-A-3-4119)
No. 9) has been proposed.

[0006]

Problems to be Solved by the Invention Japanese Patent Application Laid-Open No. 3-41199
Japanese Patent Application Laid-Open Publication No. HEI 9-107555 is directed to cleaning a carbon molded body efficiently and without damage by using chlorine fluoride gas.
It is necessary to set in the range of 0 to 350 ° C. That is,
When the temperature is lower than 100 ° C, the carbon material reacts with chlorine fluoride gas to generate an intercalation compound, while when the temperature is higher than 350 ° C, the carbon material reacts with chlorine fluoride gas to generate graphite fluoride. To do that.

To increase the cleaning efficiency, that is, to efficiently remove deposits and deposits, it is effective to increase the processing temperature with chlorine fluoride gas. However, as described above, graphite fluoride is generated. In addition, since it is difficult to perform the treatment at a high temperature of 350 ° C. or more, there is a problem that the treatment time is increased and the treatment efficiency and the treatment efficiency are reduced.

Accordingly, the present inventor has conducted research on the material properties of a carbon material which can be set at a high processing temperature with chlorine fluoride gas. Has a great influence on the reactivity with chlorine fluoride gas.

The present invention has been developed based on the above findings, and its object is to suppress the reactivity with chlorine fluoride gas even at a high temperature and to provide various members of an apparatus for producing a thin film by vapor deposition. It is an object of the present invention to provide a member for a thin film manufacturing apparatus by vapor deposition that can remove deposits and deposits generated on an exposed surface of a jig with high efficiency and high efficiency.

[0010]

In order to achieve the above object, the present invention provides a member for a thin film forming apparatus by vapor deposition, which has a surface roughness Ra of 0.05 μm or less and a porosity of 3% or less. It is characterized by comprising a glassy carbon material provided.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A glassy carbon material constituting a member for a thin film producing apparatus of the present invention is a high-strength carbonaceous material having an amorphous, homogeneous and dense structure obtained by calcining a thermosetting resin. It is a carbon material which is different from graphite material and other carbon materials in that it has excellent low chemical reactivity, gas impermeability, etc., and has few impurities. Further, it has an advantage that fine carbonaceous particles are hardly detached from the tissue, and thus is useful as a semiconductor manufacturing field which is resistant to contamination, for example, as an apparatus member for plasma etching.

In order to use the glassy carbon material having such characteristics as a member for an apparatus for producing a thin film by a vapor deposition method, the reactivity with chlorine fluoride gas was investigated. It was found that the greater the surface irregularities, the greater the reactivity. It is presumed that the reason is that chlorine fluoride gas tends to stay in the concave portions, and the staying chlorine fluoride gas accelerates the reaction.

Therefore, as the surface of the glassy carbon material is smooth and the degree of irregularities is small, that is, the smaller the surface roughness, the lower the reactivity with the chlorine fluoride gas. However, in order to reduce surface irregularities and reduce surface roughness, polishing is usually performed by buffing or diamond lapping, so that the polishing should be performed to an extent that reactivity is practically acceptable. become. As an upper limit of the suppression, the value of the surface roughness Ra is set to 0.05 μm, that is, the surface roughness Ra of the glassy carbon material is set to 0.05 μm or less. The surface roughness Ra is a value measured according to JIS B0601-1994.

In the glassy carbon material, condensed water and low-volatile components are volatilized and removed when the thermosetting resin as a raw material is cured or calcined during production, but a very small portion of the material is contained in the internal structure. And form closed internal fine pores. Some of these pores are exposed to the surface during the polishing treatment performed to reduce the surface roughness, and act like the above-mentioned irregularities on the surface to promote the retention of chlorine fluoride gas. Therefore, the reactivity increases as the number of pores increases. In the present invention, the porosity is set to 3% or less as a limit at which the reactivity with chlorine fluoride gas is allowed. The porosity is a value measured by the Archimedes method.

According to the present invention, as described above, the surface roughness Ra is set at 0.1.
Since a member or a jig of a thin film forming apparatus is formed by vapor deposition using a glassy carbon material having a property of not more than 05 μm and a porosity of not more than 3%, the reactivity with chlorine fluoride gas is suppressed. This makes it possible to remove deposits and deposits formed on exposed surfaces of members and jigs of an apparatus for producing a thin film by vapor deposition at a higher temperature.

The glassy carbon material having these properties can be produced, for example, by the following method. As a raw material, a phenol-based, furan-based or polyimide-based liquid having a residual carbon ratio of at least 40% or a thermosetting resin liquid obtained by mixing these, which is previously purified, is subjected to appropriate molding means such as molding, injection molding, casting molding or the like. Form into the desired shape.

The molded body is subjected to a curing treatment in the atmosphere at a temperature of 100 to 250 ° C., and the cured resin molded body is filled in a graphite crucible, and is heated in an electric furnace or a lead hammer furnace maintained in an inert atmosphere such as nitrogen or argon. And calcined by heating to a temperature of 800 ° C. or more. Furthermore, it is preferable that the carbonized fired body is placed in a vacuum furnace capable of replacing the atmosphere and heated to a predetermined temperature while flowing a halogen-based purified gas to perform a high-purity treatment.

[0018]

EXAMPLES Examples of the present invention will be specifically described below in comparison with comparative examples.

Reference Example In order to investigate the reaction temperature and the effect of removing deposits, the following experiment was conducted. ^On a glassy carbon material (diameter 30 mm, thickness 3 mm) having a surface roughness Ra of 0.5 μm, a porosity of 2%, and a bulk density of 1.49 g / cm ³ , a thickness of 20,000 Å by a plasma CVD method. Of Si ₃ N ₄ is deposited as a test piece, and reacted by changing the temperature at a pressure of 100 Torr using gases having different mixing ratios of ClF ₃ : Ar, and the Si ₃ N ₄ deposit is etched by the reaction. Speed was measured. The obtained results show that as shown in Table 1, the higher the reaction temperature, the higher the etching rate. In particular, when the reaction temperature is about 400 ° C., the etching rate becomes extremely high, and it can be removed in a short time. In addition,
As the reaction temperature increases, the surface of the glassy carbon material reacts with ClF ₃ to form a white powder on the surface,
It was recognized that the longer the concentration of F _{3 and} the longer the reaction time, the larger the production amount. As a result of X-ray diffraction, it was confirmed that the white substance was fluorinated graphite.

[0020]

[Table 1]

Examples 1-4, Comparative Examples 1-3 Vitreous carbon materials having different surface roughness Ra and porosity
(Diameter 30 mm, thickness 3 mm) in ClF ₃ : Ar mixed gas (mixing ratio 30:70) under a pressure of 80 Torr while changing the temperature to 20
The reaction was carried out for one minute, and the weight increase was measured. Table 2 shows the obtained results.

[0022]

[Table 2]

From the results shown in Table 2, the glassy carbon material of the embodiment having the properties specified by the present invention, that is, the properties having a surface roughness Ra of 0.05 μm or less and a porosity of 3% or less, is required to satisfy the above-mentioned requirements. In comparison with the glassy carbon material of the comparative example, the rate of weight increase due to the reaction with ClF ₃ to produce fluorinated graphite is small, and especially at a high temperature of about 400 ° C., the rate of weight increase is extremely low. It turns out that. Therefore, considering the results shown in Table 1, it is possible to remove deposits and deposits at a high etching rate without damaging the glassy carbon material by reacting at a processing temperature of about 400 ° C. It becomes possible.

[0024]

As described above, according to the member for a thin film forming apparatus by vapor phase deposition of the present invention, the surface roughness Ra is 0.05%.
Since it is formed of a glassy carbon material having a smooth surface and having a porosity of 3 μm or less and a property of 3 μm or less, the reaction with chlorine fluoride gas can be effectively suppressed.
Even at a high temperature of about 400 ° C., the generation of graphite fluoride by the reaction with chlorine fluoride gas is at a low level. Therefore, the deposits formed on the exposed surfaces of the members and jigs of the apparatus for producing a thin film by vapor deposition. It is possible to carry out the removal treatment with high efficiency and high efficiency for deposits and adhered substances. Therefore, CVD or PVD
It is extremely useful as various members and jigs used in an apparatus for producing a thin film by a method.

Claims (1)

[Claims] 1. A member for an apparatus for producing a thin film by vapor deposition, comprising a glassy carbon material having properties of a surface roughness Ra of 0.05 μm or less and a porosity of 3% or less.