Preparation device of electronic-grade silane

Abstract

The utility model provides a preparation device of electronic-grade silane. According to the preparation device, a first disproportionation reaction is carried out on the basis of the first reactor, dichlorosilane is rectified and separated to serve as a raw material for a second disproportionation reaction, silane can be obtained on the basis of cheap trichlorosilane and a catalytic reagent, and electronic-grade silane can be obtained on the basis of traditional purification after rectification; based on heat exchange between tower top materials of the rectifying tower I and a tower kettle reboiler of the rectifying tower II, differential pressure thermal coupling integration is realized, condensing equipment and operation steps can be omitted, energy consumption is reduced, and the defects of high preparation cost and high energy consumption of a silane preparation device in the prior art are overcome.

Description

TECHNICAL FIELD

[0001] The utility model relates to the preparation technical field of silane, specifically to the preparation device of electronic grade silane. BACKGROUND

[0002] With the rapid development of semiconductor very large scale integrated circuit, OLED display device, solar photovoltaic, the demand for ultra high purity silane used in the above-mentioned field manufacturing process is more and more big, in semiconductor manufacturing, electronic grade silane is an important precursor gas, is used in chemical vapor deposition process to grow various thin films on silicon wafer and other substrates.For example, it can be used for depositing polycrystalline silicon, amorphous silicon, silicon nitride and other thin films.These thin films play different roles of insulation, conduction, passivation, etc.in semiconductor devices; in flat panel display technology, thin film transistor is one of the key components.Electronic grade silane can be used to manufacture semiconductor layer in TFT through chemical vapor deposition or physical vapor deposition process; electronic grade silane can also be used to produce polycrystalline silicon and monocrystalline silicon materials for solar cells.Through chemical vapor deposition or other processes, high-quality silicon crystals can be grown on silicon wafers, improving the conversion efficiency of solar cells.

[0003] There are various preparation methods of electronic grade silane, mainly including silicon magnesium alloy method: taking silicon powder, magnesium powder and liquid ammonia as raw materials, generating silane under certain conditions.The process flow of this method is simple, but the cost is high.Silicon tetrafluoride method: using silicon tetrafluoride gas and metal hydride to generate silane.This method can use the byproduct fluorosilicic acid of enterprises to reduce cost, but a large amount of metal hydride is consumed.Chlorosilane dismutation method: preparing silane through dismutation reaction of chlorosilane, this method is simple, and is one of the main methods for producing silane in industry at present, but it still has the defect of high energy consumption.

[0004] Therefore, it is necessary to propose a new electronic grade silane preparation device to solve the problem of high cost or energy consumption in the preparation process of the prior art. UTILITY MODEL CONTENT

[0005] The utility model provides a kind of electronic grade silane's preparation device, solves the problem of high cost or energy consumption in the preparation process of prior art.

[0006] The technical scheme of the utility model is as follows:

[0007] A kind of electronic grade silane's preparation device, including reactor one, rectifying column one, rectifying column two, reactor two and post purification unit in turn communication;Wherein:

[0008] The reactor one is used for disulfuration reaction of trichlorosilane to generate dichlorodisilane and silicon tetrachloride; the rectifying column one is used for separating dichlorodisilane and feeding into the rectifying column two; the rectifying column two is used for purifying dichlorosilane and feeding into the reactor two; the reactor two is used for disulfuration reaction of dichlorodisilane to generate silane and silicon trichloride; the post-purification unit is used for separating and purifying silane to obtain electronic-grade silane;

[0009] The bottom of the rectifying column two is communicated with a reboiler two for reboiling and circulating the column bottom material; the top of the rectifying column one is provided with a reflux pipe one communicated to the top of the rectifying column one via the heat exchange medium layer of the reboiler two.

[0010] Further, the output end of the reflux pipe one is communicated to the feeding end of the rectifying column two.

[0011] Further, the top of the rectifying column two is provided with a reflux pipe two communicated to the reactor two, and the output end of the reactor two is communicated to the feeding end of the post-purification unit.

[0012] Further, the reactor one and / or the reactor two is filled with weakly basic anion exchange resin.

[0013] Further, the post-purification unit comprises a rectifying column three, a rectifying column four and a rectifying column five communicated in sequence; the output end of the reactor two is communicated to the feeding end of the rectifying column three, the top of the rectifying column three is provided with a reflux pipe three communicated to the feeding end of the rectifying column four, the column bottom of the rectifying column four is provided with a tapping pipeline communicated to the feeding end of the rectifying column five, and the top of the rectifying column five is used for tapping electronic-grade silane.

[0014] Preferably, the post-purification unit further comprises a compressor, the outlet of the compressor is provided with a compressed gas pipe, and the inlet is provided with a condensation return water main; the column bottoms of the rectifying column three, the rectifying column four and the rectifying column five are respectively provided with reboilers three, four and five for reboiling and circulating the column bottom material, and the tops are respectively provided with condensers two, three and four for condensing and returning the material; the compressed gas pipe passes through the heat supply medium layers of the reboilers three, four and five and is collected into the condensation main, and the condensation main passes through the condensing medium layers of the condensers two, three and four and is collected into the condensation return water main.

[0015] Preferably, the return water ends of the reboilers three, four and five are respectively communicated to storage tanks four, and the lower parts of the storage tanks four are communicated to the condensation main.

[0016] Preferably, the column bottom of the rectifying column three is provided with a circulation pipe two communicated to the feeding port of the rectifying column two.

[0017] Further, the column bottom of the rectifying column two is provided with a circulation pipe one communicated to the reactor one.

[0018] Compared with the prior art, the utility model has the advantages that:

[0019] The electronic-grade silane preparation device disclosed by the utility model is based on reactor one to generate the first disproportionation reaction, and dichlorodihydrogen silicon is separated by rectification as the raw material for the second disproportionation reaction, so that silane can be obtained based on inexpensive trichlorosilane and catalytic reagents, and the electronic-grade silane can be obtained based on the traditional purification after rectification; and the overhead material of rectification column one and the column still kettle reboiler of rectification column two are subjected to heat exchange, so that the differential pressure heat coupling integration is realized, the condensing equipment and the operation steps can be saved, the energy consumption is reduced, and the defects of high preparation cost and high energy consumption of the silane preparation device in the prior art are overcome. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical schemes in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings described in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained based on these drawings without creative labor.

[0021] Figure 1 The electronic-grade silane preparation device is shown in the schematic diagram of the utility model.

[0022] Figure 1 The reference signs in the drawings are as follows:

[0023] 10, feed pipe one; 11, reflux pipe one; 12, feed pipe two; 21, reflux pipe two; 22, feed pipe three; 23, circulation pipe one; 31, reflux pipe three; 32, feed pipe four; 33, circulation pipe two; 41, reflux pipe four; 42, feed pipe five; 100, compressed gas pipe; 101, backwater pipe one; 102, backwater pipe two; 103, backwater pipe three; 200, condensing main pipe; 300, condensing backwater main pipe; C1, condenser one; C2, condenser two; C3, condenser three; C4, condenser four; H1, reboiler one; H2, reboiler two; H3, reboiler three; H4, reboiler four; H5, reboiler five; R1, reactor one; R2, reactor two; S1, compressor; T1, rectification column one; T2, rectification column two; T3, rectification column three; T4, rectification column four; T5, rectification column five; V1, storage tank one; V2, storage tank two; V3, storage tank three; V4, storage tank four. DETAILED DESCRIPTION

[0024] The technical scheme of the utility model will be described clearly and completely in combination with the embodiments of the utility model. Obviously, the described embodiments are only some embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all the other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0025] Referring to Figure 1 In one embodiment, a device for preparing electronic-grade silane is provided, comprising reactors R1, rectifying column T1, rectifying column T2, reactors R2 and a post-purification unit connected in sequence; wherein: the reactor R1 is provided with a feed pipe 10 for generating dichlorodihydrogen silicon and silicon tetrachloride by dismutation of trichlorosilane; the rectifying column T1 is used for separating dichlorodihydrogen silicon and feeding into the rectifying column T2; the rectifying column T2 is used for purifying dichlorohydrogen silicon and feeding into the reactor R2; the reactor R2 is used for generating silane and silicon trichloride by dismutation of dichlorodihydrogen silicon; and the post-purification unit is used for separating and purifying silane to obtain electronic-grade silane.

[0026] The column still of the rectifying column T2 is connected with a reboiler H2 for reboiling and circulating the column still material; and the top of the rectifying column T1 is provided with a reflux pipe 11 connected to the top of the rectifying column T1 via the heat exchange medium layer of the reboiler H2.

[0027] In the above embodiment, the device is based on the first dismutation reaction of trichlorosilane to generate tetrachlorohydrogen silicon and dichlorodihydrogen silicon, and the dichlorodihydrogen silicon is separated by rectification and used as the raw material for the second dismutation reaction. The silane can be obtained based on the inexpensive trichlorosilane and the catalytic reagent, and the electronic-grade silane can be obtained based on the traditional rectification and post-purification. Since the rectifying column T1 needs to separate silicon tetrachloride and dichlorohydrogen silicon, the rectification operating pressure and temperature of the rectifying column T1 are higher than those of the rectifying column T2. The heat exchange between the column top material of the rectifying column T1 and the reboiler of the column still of the rectifying column T2 is realized, the heat coupling integration is realized, the condensing equipment and the operating steps can be saved, and the energy consumption is reduced.

[0028] In a preferred embodiment, the column still of the rectifying column T1 is provided with a reboiler H1 for reboiling to improve the rectification efficiency; the reflux pipe 11 is connected to the feed end of the rectifying column T2 at the output end of the reboiler H2. The top of the rectifying column T2 is provided with a reflux pipe 21 connected to the reactor R2, and the output end of the reactor R2 is connected to the feed end of the post-purification unit. The above-mentioned mode realizes the continuous feeding of the separated distillate or product, and improves the production efficiency.

[0029] In a preferred embodiment, the reactors R1 and R2 are respectively filled with weakly basic anion exchange resins, such as common cross-linked polystyrene type weakly basic anion resins, vinyl cyclic tertiary amine polymer resins, etc., and the same or different catalysts can be adaptively selected.

[0030] In some embodiments, in order to obtain electronic grade silane, the post purification unit can be provided with multiple rectification towers in parallel. Specifically, the post purification unit comprises rectification tower three T3, rectification tower four T4 and rectification tower five T5 which are sequentially connected; the outlet end of the reactor two R2 is connected to the inlet end of the rectification tower three T3, the top of the rectification tower three T3 is provided with a reflux pipe three 31, the reflux pipe three 31 is connected to the inlet end of the rectification tower four T4; the tank of the rectification tower four T4 is provided with a pipeline for collecting the inlet end of the rectification tower five T5; the top of the rectification tower five T5 is used for collecting electronic grade silane.

[0031] In the above embodiments, in the post purification unit, the rectification tower three T3 is used for separating unconverted trichlorosilane and dichlorodisilane from the tank, and separating silane from the top to obtain a crude product; the rectification tower four T4 is mainly used for removing trace light component impurities such as hydrogen, nitrogen, oxygen, argon, carbon monoxide and methane from the top of the silane, and collecting the purified silane from the tank; the rectification tower five T5 is used for removing trace heavy component impurities such as monochlorotrihydrogen silane, dichlorodisilane and trichlorosilane from the tank, and then collecting electronic grade silane from the top. Those skilled in the art can select appropriate rectification operating pressure and temperature parameters to ensure the purity of rectification according to the target separation product.

[0032] In preferred embodiments, the post purification unit further comprises a compressor S1, the outlet of the compressor S1 is provided with a compressed gas pipe 100, and the inlet is provided with a condensation backwater main pipe 300; the tanks of the rectification tower three T3, the rectification tower four T4 and the rectification tower five T5 are respectively provided with reboilers three H3, reboilers four H4 and reboilers five H5 for reboiling circulation of the tank materials, and the tops are respectively provided with condensers two C2, condensers three C3 and condensers four C4 for condensation reflux of the materials; the compressed gas pipe 100 passes through the heat supply medium layers of the reboilers three H3, the reboilers four H4 and the reboilers five H5, and is collected to the condensation main pipe 200 by the backwater pipe one 101, the backwater pipe two 102 and the backwater pipe three 103, and the condensation main pipe 200 passes through the condensation medium layers of the condensers two C2, the condensers three C3 and the condensers four C4 and is collected to the condensation backwater main pipe 300.

[0033] In the above embodiments, the post purification unit adopts a three-stage rectification tower integrated heat pump rectification technology, which not only realizes the function of providing heat source and cold source in the rectification process, solves the problem of needing steam (hot water) and low-temperature chilled water in the rectification process, but also greatly reduces the energy consumption of the whole process by using the high efficiency of compression heat exchange, saving about 65% of energy compared with traditional rectification. In addition, three independent heat pump rectifications are integrated into a universal system through optimization and integration of process parameters, which greatly saves the heat pump system equipment, reduces the operation complexity and control difficulty, and saves the system investment cost.

[0034] In some embodiments, the medium used in the heat pump rectification system used by the post-purification unit can be ammonia, fluorochlorohydrocarbon, R13, R14, R23, R508B, R503 or other equivalent conventional medium-temperature refrigerant, whose compression pressure and expansion pressure match the use temperature.

[0035] In some embodiments, to ensure the stability of the feed and the efficiency of the rectification, a storage tank V1 is arranged between the rectification column T1 and the rectification column T2, the reflux pipe 11 is further connected to the storage tank V1 via the reboiler H2, the lower part of the storage tank V1 is connected to the top of the rectification column T1, and a feed pipe 12 is arranged on the reflux output pipeline of the storage tank V1 and connected to the middle part of the rectification column T2. To improve the utilization rate of the raw material, a circulation pipe 23 is arranged on the column bottom of the rectification column T2 and connected to the reactor R1.

[0036] In some embodiments, to ensure the stability of the feed and the efficiency of the rectification, a condenser C1 is arranged on the top of the rectification column T1, a storage tank V2 is connected to the condenser C1, the lower part of the storage tank V2 is connected to the top reflux of the rectification column T2, and a feed pipe 22 is arranged on the lower part of the storage tank V2 and connected to the reactor R2 and further connected to the middle part of the rectification column T3. To improve the utilization rate of the raw material, a circulation pipe 33 is arranged on the column bottom of the rectification column T3 and connected to the feed inlet of the rectification column T2.

[0037] In some embodiments, to ensure the stability of the feed and the efficiency of the rectification, for the post-purification unit: the reflux pipe 31 is connected to the storage tank V3 via the condenser C2, the lower part of the storage tank V3 is connected to the top of the rectification column T3, and a feed pipe 32 is arranged on the lower part of the storage tank V3 and connected to the upper feed end of the rectification column T4. The reflux pipe 41 is arranged on the top of the rectification column T4 and connected to the top via the condenser C3, a feed pipe 42 is arranged on the column bottom of the rectification column T4 and connected to the middle part of the rectification column T5. The water return ends of the reboilers H3, H4 and H5 are connected to the storage tank V4, and the lower part of the storage tank V4 is connected to the condensing main pipe 200.

[0038] As a conventional setting in the art, the preparation device further includes a power pump for providing material transfer, a valve for pipeline control, and an instrument for monitoring the working condition, which are not described herein.

[0039] The above merely describes preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. Apparatus for the production of electronic grade silane, characterised in that, The system comprises reactors one (R1), rectifying column one (T1), rectifying column two (T2), reactors two (R2) and post purification unit in sequence; The reactor one (R1) is used for generating dichlorodihydrogen silicon and silicon tetrachloride from trichlorosilane; The rectifying column one (T1) is used for separating dichlorodihydrogen silicon and feeding into the rectifying column two (T2); the rectifying column two (T2) is used for purifying dichlorosilane and feeding into the reactor two (R2); The reactor two (R2) is used for generating silane and silicon trichloride from dichlorodihydrogen silicon; The post purification unit is used for separating and purifying silane to obtain electronic grade silane; The rectifying column two (T2) is connected with reboiler two (H2) at the column bottom for reboiling and recycling the column bottom material; the rectifying column one (T1) is provided with reflux pipe one (11) at the column top, which is connected to the column top of the rectifying column one (T1) via the heat exchange medium layer of the reboiler two (H2).

2. The preparation device according to claim 1, characterized in that The reflux pipe one (11) is connected to the feeding end of the rectifying column two (T2) at the output end of the reboiler two (H2).

3. The preparation device of claim 1, wherein The rectifying column two (T2) is provided with reflux pipe two (21) at the column top and connected to the reactor two (R2), and the output end of the reactor two (R2) is connected to the feeding end of the post purification unit.

4. The preparation device of claim 1, wherein The reactor one (R1) and / or the reactor two (R2) is filled with weakly basic anion exchange resin.

5. The preparation device of claim 1, wherein The post purification unit comprises rectifying column three (T3), rectifying column four (T4) and rectifying column five (T5) in sequence; the output end of the reactor two (R2) is connected to the feeding end of the rectifying column three (T3), the rectifying column three (T3) is provided with reflux pipe three (31) at the column top and connected to the feeding end of the rectifying column four (T4); the column bottom of the rectifying column four (T4) is connected to the feeding end of the rectifying column five (T5) via the extraction pipeline; and the column top of the rectifying column five (T5) is used for extracting electronic grade silane.

6. The preparation device of claim 5, wherein The post purification unit further comprises compressor (S1), which is provided with compressed gas pipe (100) at the outlet and condensation return water main pipe (300) at the inlet; the column bottoms of the rectifying column three (T3), rectifying column four (T4) and rectifying column five (T5) are respectively provided with reboiler three (H3), reboiler four (H4) and reboiler five (H5) for reboiling and recycling the column bottom material, and are respectively provided with condenser two (C2), condenser three (C3) and condenser four (C4) for condensing and returning the column top material; the compressed gas pipe (100) passes through the heat supply medium layer of the reboiler three (H3), reboiler four (H4) and reboiler five (H5) and converges into condensation main pipe (200), which passes through the condensation medium layer of the condenser two (C2), condenser three (C3) and condenser four (C4) and converges into condensation return water main pipe (300).

7. The preparation device of claim 6, wherein The return water ends of the reboiler three (H3), reboiler four (H4) and reboiler five (H5) are respectively connected to storage tank four (V4), and the lower part of the storage tank four (V4) is connected to the condensation main pipe (200).

8. The preparation device of claim 5, wherein The column bottom of the rectifying column three (T3) is provided with circulation pipe two (33) and connected to the feeding port of the rectifying column two (T2).

9. The preparation device of claim 1, wherein, The distillation column two (T2) column still is provided with a circulation pipe one (23) in communication with the reactor one (R1).

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