JPS59164614A - Manufacture of monosilane - Google Patents

Abstract

PURPOSE:To manufacture monosilane in a high yield by bringing a silicon halide into contact with a perfluorocarbon-base cation exchange body having sulfonic acid groups at a specified temp. CONSTITUTION:Vapor of a silicon halide such as tetrachlorosilane, trichlorosilane, dichlorosilane or monochlorosilane is passed through a reaction system packed with an insoluble polymer having sulfonic acid groups and fluorine atoms bonded to carbon atoms at 150-240 deg.C to cause a reaction. The insoluble polymer is a cation exchange body having a skeleton of perfluorocarbon and sulfonic acid groups bonded to the side chain. The resulting monosilane contains other product and the unreacted gas, so only monosilane is separated by distillation or other method by making use of the difference in b.p.

Description

[Detailed Description of the Invention] The present invention relates to a method for producing monosilane.
The present invention relates to a method for producing monosilane from silicon rogonide in good yield.

Monosilane is a useful substance in the semiconductor industry, especially as a high-purity semiconductor-grade silane or a raw material for silicon precipitation for amorphous solar cells, and as a raw material for epitaxial use, and further increases in KlfllN are expected in the future. Therefore, it is desired to develop a better and cheaper method for producing monosilane.

Conventionally known methods for producing monosilane include (1) Method M in which magnesium silicide is reacted with ammonium chloride in liquid ammonia, 9.81+4;
NH4Ct-+ SiH, +2M, 9C7, +4NH8
(2) Tetrachlorosilane in ether with LiAt
Method of reduction by H, 5iCt, +LiAtH4→SiH, +AtCt8+C
Method of disproportionation reaction of 1Ct(3) trichlorosilane using tertiary amine anion exchange resin 4H81C48
= 81H, +3SiH.

Although the method (1) above has been put into practical use industrially, the equipment cost is high because it requires reaction at extremely low temperatures. (2)
Since LiAtH4 is an extremely expensive reducing agent, it is difficult to put it into practical use. Moreover, since the heat resistance temperature of the fallen ion exchange resin is low, the method (3) is disadvantageous in terms of reaction kinetics, and the yield of monosilane is low.

The present inventors have conducted extensive research on a method for manufacturing monosilane from silicon halide at low cost and easily. As a result, the inventors discovered that monosilane can be obtained in extremely high yield by bringing silicon halide into contact with a perfluorocarbon-based cation exchanger having a sulfonic acid group, which led them to propose the present invention. .

In the present invention, the reason why monosilane can be obtained in high yield from oxidized silicon halide is not clear, but the reason is that the sulfonic acid group of the cation exchanger brought into contact with the silicon halide is a super strong acid and is perfluorocarbon type. Therefore, since the reaction temperature can be set extremely high, it is presumed that these factors interact with each other to produce more effects than expected.

The silicon 10genide used in the present invention is generally tetrachlorosilane or trichlorosilane.

Dichlorosilane and monochlorosilane are suitable, but silicon tetrafluoride and silicon tetrabromide are also suitable.

Nationally approved silicon can also be used.

The perfluorocarbon cation exchanger having a sulfonic acid group of the present invention is an insoluble polymer compound in which a sulfonic acid group and a fluorine atom are bonded to a carbon atom. A polymer in which atoms are bonded is preferred. Specifically, it is a cation exchanger with a perfluorocarbon skeleton and a sulfonic acid group bonded to the side chain, such as tetrafluoroethylene and perfluoro(furkyl ether sulfonylfluorocarbon) known as DuPont's Nafion (trade name). It is preferable to co-electrolyze and hydrolyze a compound (Ride). It is also desirable to maintain the cation':1 exchanger of the present invention in an effective catalytic form by contacting it with a silicon halide. Therefore, the shape of the cation exchanger is generally preferably granular, but it can also be shaped into powder, fiber, tube, etc. as needed.
It may be manufactured as appropriate from the perfluorocarbon-based polymer described above.

In the present invention, the method of contacting the silicon halide with the perfluorocarbon cation exchanger having a sulfonic acid group is not particularly limited, but in general, vapor of the silicon halide is introduced into a reaction system filled with the cation exchanger. A method of supplying and distributing is adopted.

Although the reaction temperature in the present invention is raised, the yield of the monosilane produced can be improved, particularly at temperatures above 150°C, but at temperatures above 300°C the durability of the cation exchanger is poor. However, the reaction temperature of the present invention is generally 50 to 250
℃, preferably 150 to 230℃. Further, the contact time of the cation exchanger with the silicon noerogonide in the present invention is appropriately determined in consideration of other conditions such as the above-mentioned reaction temperature, but generally a short time is sufficient.

(5) From the reaction product gas obtained by the present invention, the target monosilane can be easily separated by distillation or the like using the boiling point of the monosilane from other products and unreacted gas.

Examples are given below, but the present invention is not limited thereto.

Example 1 DuPont's Nafion 501 (trade name) 1, which is a sulfonic acid type perfluorocarbon cation exchange resin
0g was preliminarily stirred in a solution of methanol and diconcentrated hydrochloric acid = 1:1.

After washing with water and drying in vacuum, it was filled into a quartz glass reactor with an inner diameter of 30 mm, and tetrachlorosilane was used as the raw material silicon halide.

Trichlorosilane and dichlorosilane were each 0.
The reaction temperature was maintained at 180 °C by continuously feeding with a current of 15 t/m.

The reaction product gas after 3 hours when the reaction becomes steady is
It was analyzed using a gas chromatogram using a gas sampler. The results are shown in Table 1 (6).

Table 1 Example 2 Sulfonic acid type perfluorocarbon cation exchange m
As 8'ft, DuPont Na-fion-51
1 (Mt product name), 0.5 g of trichlorosilane and dichlorosilane each in the same manner as in Example 1.
The reaction was carried out at a flow rate of t/mm and a reaction temperature of 220°C. The results are shown in Table 2.

Table 2 Examples 3 and 4 As a sulfonic acid type perfluorocarbon cation exchange resin, DuPont's Na-fion 501
(Product name) 10II and in the same manner as in Example 1.
Lachlorsilane latrique ρrusilane and dichlorosilane were respectively o, tsz/= flow rate and reaction temperature 80
℃.

It was carried out at 130°C. The results are shown in Table 3.

(l) (9) (8) Comparative Example 10 parts of No. 31i & amine-type anion exchange resin 7 Number List A-21 (manufactured by Haas Andohm, trade name) were treated in advance with a methanol solution and washed with water. , after drying,
In the same manner as in Example 1, tetrachlorsilane, trichlorosilane and dichlorosilane were each added at 0.1st/m.
The reaction temperature was maintained at 80°C. The results are shown in Table 4.

(1G)

Claims (1)

[Claims] (1) A method for producing monosilane characterized by contacting halogenated silicon with a perfluorocarbon cation exchanger having a sulfonic acid group at a temperature of +21150 to 240°C Claim 1 The manufacturing method according to claim 1 (31-) The manufacturing method according to claim 1, wherein the silicon halogenide is tetrachlorosilane latric prusilane, dichlorosilane or monochlorosilane.