JPH0829929B2 - Method for producing hydrohalogenated silane - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a hydrohalogenated silane. In particular, it relates to a method for producing monochlorosilane and dichlorosilane.

[Problems to be Solved by Prior Art and Invention]

Demand for monosilane and trichlorosilane for semiconductor epitaxial films, oxide films, and nitride films has been increasing in recent years. However, with trichlorosilane, there are problems that chlorine tends to remain in the formed film and that the oil in the vacuum pump is severely deteriorated. With monosilane, there is no problem caused by chlorine, but there is a problem that the quality of the formed film is poor. It was For this reason, there has been a demand for an inexpensive method for producing monochlorosilane or dichlorosilane, which is considered to have an intermediate property between trichlorosilane and monosilane.

Known methods for producing this monochlorosilane include, for example, a method of reacting monosilane and hydrochloric acid in the presence of aluminum chloride, and a method of disproportionation of dichlorosilane.

However, in the method of reacting monosilane and hydrochloric acid in the presence of aluminum chloride, the starting hydrochloric acid is likely to remain in the produced monochlorosilane, and this residual hydrochloric acid causes corrosion of the equipment and also reduces the adhesion strength of the produced film. Since it causes a problem, it is unsuitable for use as a semiconductor.

Further, the method by disproportionation of dichlorosilane means that monochlorosilane, monochlorosilane,
This is a method for producing trichlorosilane, but in this reaction, the production rate of monochlorosilane is as low as ten and several percent,
There is also a problem that it is difficult to treat the trichlorosilane produced as a by-product.

As a method for producing dichlorosilane, there is a method for separating and purifying dichlorosilane produced as a by-product when producing polysilicon by reducing trichlorosilane. However, this method has a problem that the production amount cannot be adjusted. Also, using industrially mass-produced trichlorosilane,
Although dichlorosilane can be easily produced by the method of producing dichlorosilane by disproportionation, there is a problem in that the treatment is troublesome because an equimolar amount of silicon tetrachloride is produced as a by-product at the same time as dichlorosilane.

An object of the present invention is to provide a method for efficiently producing monohalogenated silane and dihalogenated silane, particularly monochlorosilane and dichlorosilane.

[Means and Actions for Solving Problems]

Conventionally, dichlorosilane and silicon tetrachloride were produced from trichlorosilane in the presence of a disproportionation catalyst (Japanese Patent Publication No. 52-18).
678) and the production of monosilane and silicon tetrachloride from trichlorosilane (JP-A-50-119798), and also the production of monosilane, monochlorosilane and trichlorosilane from dichlorosilane. (Japanese Patent Publication No. 52-18678). However, it has never been known to produce monochlorosilane and dichlorosilane from a mixture of monosilane and trichlorosilane.

On the other hand, as a result of diligent studies, the present inventors have surprisingly easily produced monochlorosilane and dichlorosilane by contacting a mixture of monosilane and trichlorosilane in the presence of a disproportionation catalyst. When only one of monochlorosilane and dichlorosilane is required, it is possible to obtain only the target component in high yield by recycling the other as a raw material, and
The inventors have found that the product contains almost no hydrogen chloride and have completed the present invention.

That is, the present invention is a method for producing a monohalogenated silane and a dihalogenated silane, which comprises contacting a mixture of monosilane and trihalogenated silane in the presence of a disproportionation catalyst.

The feature of the present invention is to use monosilane, which can be easily produced by a method of reacting magnesium silicide with hydrochloric acid, or a method of reducing silicon tetrachloride with lithium aluminum hydride, and trichlorosilane, which is industrially mass-produced, as raw materials. The manufacturing cost can be reduced by recycling the by-product, and the manufacturing amount can be easily adjusted.

The disproportionation catalyst used in the present invention is described below. For example, nitriles such as adiponitrile described in U.S. Pat.No. 2732282, aliphatic cyanamides described in U.S. Pat.No. 2,732,280, aliphatic amines such as trimethylamine described in U.S. Pat.No. 2,834,648, and Japanese Patent Publication No. 55-14045. Described N
-Substituted pyrrolidone, tetraalkylurea described in JP-B-55-14046, anion exchange resin described in JP-B-52-18678, reaction product of amino alcohol and silica described in JP-A-59-156907. The reaction products of amines and silica described in JP-A-61-187936, the polymers of pyrroles described in JP-A-61-256912, and the like. Which of these catalysts is used may be appropriately determined depending on the activity of the catalyst, the temperature and pressure of the manufacturing process, and the like.

When a mixture of trichlorosilane and monosilane is used as the raw material, the molar ratio of the mixture may be trichlorosilane / monosilane = 0.1 to 10, preferably 0.3 to 2.0.

In addition, when separating and purifying only the necessary components from the generated monochlorosilane and dichlorosilane and recycling the remaining components, monosilane and trichlorosilane are added to add the total number of chlorine atoms and the total number of hydrogen atoms in the raw material. The ratio of 0.
It may be 1 to 10, preferably 0.3 to 2. Further, this raw material may be mixed with silicon tetrachloride, nitrogen, hydrogen, argon or the like.

In contacting the catalyst with the raw material, the raw material may be supplied to the flow type or batch type reactor in a gas phase or liquid phase state.

The reaction temperature may vary depending on the type of catalyst used, temperature, etc., but is usually about 40 to 200 ° C.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to Examples.

Example 1 By the method of Example 1 described in JP-A-61-187936,
10 g of catalyst prepared using diethylenetriamine, ethyl alcohol, silica gel of 35 to 48 mesh, inner diameter 8 mm,
It was filled in a U-shaped SUS tube flow type reactor having a length of 40 cm. After that, while flowing helium to sufficiently replace the inside of the reactor with helium, the reactor was heated to 100 ° C. in an oil bath. Reactor is 100 ° C
After that, the supply of helium was stopped, and trichlorosilane gas with a purity of 99.9% was added at 30cc / min (at room temperature) and monosilane gas.
30cc / min (at room temperature) was mixed and supplied. The reaction product was collected in a gaseous state, and the composition of the reaction product was analyzed by gas chromatography.

According to the analysis result, monosilane 34mole%, monochlorosilane 11mole%, dichlorosilane 25moie%, trichlorosilane 32moie%, and formation of dichlorosilane and monochlorosilane was confirmed. Hydrogen chloride was not detected.

Example 2 10 cc of poly-N-methylpyrrole catalyst prepared by the method of Example 3 described in JP-A-61-256912 was used to obtain an inner diameter of 8 m.
It was filled in a U-shaped SUS tube flow type reactor having a length of m and a length of 40 cm.
Thereafter, while flowing helium to sufficiently replace the inside of the reactor with helium, the reactor was heated to 140 ° C. in an oil bath. 140 reactors
After reaching ℃, the supply of helium was stopped, and 30 cc / min of trichlorosilane gas having a purity of 99.9% (at room temperature) and 30 cc / min of monosilane gas (at room temperature) were mixed and supplied. The reaction product was collected in a gaseous state, and the composition of the reaction product was analyzed by gas chromatography.

According to the analysis results, monosilane 36 mole%, monochlorosilane 12 mole%, dichlorosilane 18 mole% and trichlorosilane 34 mole% were confirmed, and formation of dichlorosilane and monochlorosilane was confirmed. Hydrogen chloride was not detected.

Example 3 10 g of the catalyst prepared by the method of Example 1 described in JP-A-61-187936 was used to make a U-shaped SUS having an inner diameter of 8 mm and a length of 40 cm.
It was filled in a tube flow type reactor. After that, while flowing helium to sufficiently replace the inside of the reactor with helium, set the reactor in an oil bath.
Heated to 120 ° C. After the reactor reached 120 ° C, the supply of helium was stopped and trichlorosilane gas with a purity of 99.9% was added at 30cc / m.
in (normal temperature conversion) and monosilane gas 60cc / min (normal temperature conversion)
Were mixed and supplied. The reaction product was collected in a gaseous state, and the composition of the reaction product was analyzed by gas chromatography.

According to the analysis results, the content of monosilane was 48 mole%, monochlorosilane was 16 mole%, dichlorosilane was 22 mole%, and trichlorosilane was 13 mole%, and formation of dichlorosilane and monochlorosilane was confirmed. Hydrogen chloride was not detected.

Example 4 Amberlyst A-21, a weakly basic ion exchange resin manufactured by Rohm and Haas Company, USA, was dehydrated by washing with acetone, and 10 cc of a U-shaped SUS pipe having an inner diameter of 8 mm and a length of 40 cm was flow-through The reactor was charged. After that, while flowing helium to sufficiently replace the inside of the reactor with helium, the reactor was heated to 60 ° C. in an oil bath. After the reactor reached 60 ° C., the supply of helium was stopped, and 30 cc / min (normal temperature conversion) of trichlorosilane gas having a purity of 99.9% and 30 cc / min (normal temperature conversion) of monosilane gas were mixed and supplied. The reaction product was collected in a gaseous state, and the composition of the reaction product was analyzed by gas chromatography.

According to the analysis result, monosilane 30mole%, monochlorosilane 15mole%, dichlorosilane 30mole% and trichlorosilane 25mole% were confirmed, and the formation of dichlorosilane and monochlorosilane was confirmed.

Example 5 The reaction product of Example 4 was collected in a stainless steel container cooled with liquid nitrogen. The collected reaction product was subjected to pressure distillation twice to separate only monochlorosilane. The residue was an equimolar mixture of monosilane, dichlorosilane and trichlorosilane.

U filled with Amberlyst A-21 used in Example 4
A flow type reactor made of letter SUS pipe was heated to 60 ° C in an oil bath.
After the reactor reached 60 ° C, monosilane was mixed with the gasified product of the equimolar mixture of dichlorosilane and trichlorosilane described above, and 40 mole% of monosilane and 40 mole% of dichlorosilane were mixed.
It was supplied to the reactor so that 30 mole% and trichlorosilane became 30 mole%. The supply rate was 60 cc / min at room temperature.

The reaction product was collected in a gaseous state, and the composition of the reaction product was analyzed by gas chromatography. According to the analysis result, monosilane 29mole%, monochlorosilane 16mole%,
It was 31 mol% of dichlorosilane and 24 mol% of trichlorosilane, and formation of dichlorosilane and monochlorosilane was confirmed.

〔The invention's effect〕

As shown in the above examples, monochlorosilane and dichlorosilane could be easily produced by contacting monosilane and trichlorosilane in the presence of a disproportionation catalyst.

Claims (1)

[Claims] 1. A method for producing a monohalogenated silane and a dihalogenated silane, which comprises contacting monosilane with a trihalogenated silane in the presence of a disproportionation catalyst.