JPH0317770B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel reaction apparatus particularly suitable for a reaction in which crystals produced by a chemical reaction are attached to a core rod provided in a reaction chamber. Specifically, a reaction chamber is constituted by a chamber frame having a gas inlet and a gas outlet, and a wall material, a current-carrying part configured by connecting both ends of a conductive rod to a pair of power terminals is provided in the reaction chamber, and a wall material is provided. is a reaction device made of transparent quartz with a reflective film on its outer surface.

Various types of reaction apparatuses are known depending on the target reaction. For example, a reaction in which a chemical reaction occurs under high temperature on a core rod installed in a reaction chamber, and the resulting crystals adhere to and grow on the core rod. For example, trichlorosilane is reduced and thermally decomposed with hydrogen in the reaction chamber, and silicon is pre-prepared. Corrosion-resistant and heat-resistant materials are used for the core rod and reaction equipment used for growth reactions. More specifically, a reaction apparatus is known in which a reaction chamber is constructed of a chamber frame and a wall material having a gas inlet and a gas outlet, and both ends of a conductive rod are connected to a pair of power supply terminals in the reaction chamber. It is being In this case, the electric current supplied from the power supply is converted into thermal energy by the conductive rod due to its resistance, thereby maintaining a high reaction temperature. Furthermore, the above-mentioned reactions at high temperatures often involve the generation of corrosive gases. Therefore, the wall material is made of corrosion-resistant and heat-resistant stainless steel or opaque quartz. However, if the latter, that is, opaque quartz, is used as a wall material, the wall material itself absorbs heat, making it impossible to avoid heat source loss.

The present invention proposes that the above drawbacks can be completely eliminated by using transparent quartz as the material of the wall material and providing a reflective film on the outer surface of the wall material to prevent absorption of the heat source and to make the heat source participate in the reaction. I found out,
It has been completed.

That is, in the present invention, a reaction chamber 5 is constituted by a chamber frame 3 having a gas inlet 1 and a gas outlet 2 and a wall material 4, and both ends of a conductive rod 6 are connected to a pair of power supply terminals 7 in the reaction chamber. The reactor is equipped with a energized section, and the wall material is made of transparent quartz with a reflective film on the outer surface.

In order to explain the present invention in detail, a reaction apparatus suitable for the reaction of reducing and thermally decomposing trichlorosilane with hydrogen and producing silicon will be described below in accordance with the attached drawings. The target reaction of the reaction apparatus is not limited to, and any reaction may be performed.

The accompanying drawings, FIGS. 1 and 2, are each a cross-sectional view showing a typical reaction apparatus of the present invention.

The reactor of the present invention has a gas inlet 1 and a gas outlet 2.
A reaction chamber is constituted by a chamber frame 3 and a wall material 4. Although it is common to provide one gas inlet 1 and one gas outlet 2, a plurality of gas inlets 1 and gas outlets 2 may be provided. Further, the shapes of the gas inlet 1 and the gas outlet 2 are not particularly limited. For example, trichlorosilane and hydrogen may be mixed in advance and supplied into the reaction chamber from a single gas inlet, or trichlorosilane, hydrogen, or diluent gas, if necessary, may be supplied from separate tubes using multiple tubes of double or more. They can also be supplied so as to be mixed within the tube supply port or within the reaction chamber. Also room frame 3
The material is not particularly limited, and may be suitably selected from known materials with good corrosion resistance. Examples of materials that are generally preferably used include quartz, gold, silver, copper, and stainless steel.

It is essential that the wall material 4 used in the present invention is transparent quartz 9. The reason for this is to prevent thermal energy from being absorbed by the quartz and generating heat. However, if transparent quartz is simply used, all the thermal energy involved in the reaction will be scattered outside the reaction chamber, so as a means to prevent this disadvantage, in the present invention, a reflective film 8 is provided on the outer surface of the transparent quartz that constitutes the wall material. establish. The reflective film is provided in order to use the thermal energy involved in the reaction more efficiently by reflecting it even if it passes through the transparent quartz and using it as a heat source for the reaction. In general, the material of the reflective film is not particularly limited, but it is preferable to use it as integrated with the wall material as possible, and it is also preferable that it has as good a reflectance as possible.
Must be heat resistant. For this reason, metal films such as gold, silver, copper, or aluminum are preferably used. The means for providing the reflective film on the outer surface of the transparent quartz is not particularly limited, and any means may be employed. In general, it is most effective to integrate the material onto the outer surface of the transparent quartz wall material by means such as vacuum deposition, sputtering, or electroless plating.

In the reaction chamber of the present invention, it is necessary to provide a current-carrying section in which both ends of a conductive rod 6 are connected to a pair of power supply terminals 7. Although the conductive rod is not particularly limited, silicon produced by reductive thermal decomposition of trichlorosilane adheres to it and acts as a growing core material, and when electricity is applied, it generates heat due to the resistance of the conductive rod itself. A rod made of polycrystalline or single-crystalline silicon is most suitable because it serves to convert energy into thermal energy. Of course, in addition to the above-mentioned silicon, for example, a tantalum bar or the like can be used if necessary as long as it is conductive.

As is clear from the above explanation, the electrical current is converted into thermal energy by the conductive rod 6 connected to the power supply terminal, and the reaction temperature can be maintained. The thermal energy passes through the transparent quartz wall material, but is fed back to the reaction chamber again by the action of the reflective film provided on the outer surface of the wall material, and is utilized efficiently as radiant heat.

In addition, FIG. 1 is an explanatory view showing a reaction apparatus in which the conductive rod 6 is set in a U-shape, and FIG. 2 is an explanatory view showing a typical embodiment in which the conductive rod 6 is set in the shape of one rod.
In the figure, 10 indicates a holder for the conductive rod. Further, although the chamber frame 3 is made of a non-conductive material, it goes without saying that an insulator is provided between it and the power supply terminal 7 to make it a conductive material.

The reactor used for the thermal decomposition reaction was a typical type that consumed a lot of power because it generated high heat, but with the completion of the present invention, the power consumption is significantly lower, for example, about 60% of that of conventional equipment. reaction equipment, making an immeasurable contribution to industry.

Example In the configuration shown in Figure 1, the wall material was a transparent quartz container with an inner diameter of 400 mm, a height of 1900 mm, and a wall thickness of 20 mm.A thin silver film of about 0.1 mm in thickness was attached to the outer wall using a silver mirror reaction. Ta. A pair of electrodes are placed at a spacing of 300 mm, and a U-shaped polycrystalline silicon rod (5 mmφ) is premixed with trichlorosilane and hydrogen at a ratio of 1:10 while maintaining the surface temperature at 1150°C. The reduction and thermal decomposition reaction of trichlorosilane was carried out. The resulting silicon was grown into a U-shaped polycrystalline silicon rod with a height of 1,500 mm and a maximum diameter of 200 mm. The power required at this time was 15,000 kilowatt hours. For comparison, a polycrystalline bar was manufactured under the same conditions except that the material for the wall material was opaque quartz, and the power consumption was 25,000 kilowatt hours.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views showing typical reactors of the present invention. In the figure, 1 is a gas inlet, 2 is a gas outlet, 3 is a chamber frame, 4 is a wall material, 5 is a reaction chamber, 6 is a conductive rod, 7 is a power terminal, 8 is a reflective film, and 9 is transparent quartz. .

Claims (1)

[Scope of Claims] 1 A reaction chamber 5 is constituted by a chamber frame 3 having a gas inlet 1 and a gas outlet 2 and a wall material 4, and both ends of a conductive rod 6 are connected to a pair of power terminals 7 in the reaction chamber. A reaction device is provided with a current-carrying part configured as shown in FIG. 2. The reaction device according to claim 1, wherein the wall material is an integral part of a reflective film and transparent quartz.