CN101987730B - Method for removing trace impurities in silicane - Google Patents
Method for removing trace impurities in silicane Download PDFInfo
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- CN101987730B CN101987730B CN2009101092067A CN200910109206A CN101987730B CN 101987730 B CN101987730 B CN 101987730B CN 2009101092067 A CN2009101092067 A CN 2009101092067A CN 200910109206 A CN200910109206 A CN 200910109206A CN 101987730 B CN101987730 B CN 101987730B
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- cation exchange
- exchange resin
- silane
- large pores
- adsorption tower
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Abstract
The invention discloses a method for removing trace impurities in silicane, which comprises the following steps of: utilizing and modifying macropore type cation exchange resin; and filling the modified macropore type cation exchange resin into an adsorption tower, and ensuring that silicane gas passes through after being deoxygenized through blowing. The provided method for removing the trace impurities in silicane remarkably removes trace components, such as B2H6, PH3, AsH3, and the like in the silicane so that the content of each component is reduced below 0.5*10<-9> and achieves using requirements of electronic and semiconductor industries on high purity silicane.
Description
Technical field
The present invention relates to a kind of semiconductor photovoltaic industry with high purity silane preparation method, particularly relate to the removal method of trace impurity in a kind of silane.
Background technology
Silane is claimed single silane and silicomethane again, and molecular formula is SiH
4, relative molecular mass 32.12.SiH
4Under normal temperature, normal pressure for a kind of colourless, stinkpot, high reactivity and coercible gas arranged.SiH
4Gas is most important kind in the electronic gas, and it is as polycrystalline silicon semiconductor, epitaxial film generation, non-crystalline silicon, silicon device removal of impurities film and gather the virgin gas of silicon fiml.The method of preparation has LiAlH
4Method (lithium aluminum hydride method), " A-F silane thermal decomposition process " (also claiming magnesium silicide method), halogenated silanes discrimination method etc.China's most domestic adopts magnesium silicide method, and it is to make magnesium silicide and industrial NH
4Chemical reaction takes place and produces SiH in C1 (ammonium chloride) in the liquefied ammonia medium
4
No matter adopt which kind of method to prepare SiH
4, there are some impurity in the product more or less, their kind and content depend on production technique.These impurity can influence SiH to some extent
4Application, particularly in electronics and semicon industry, require SiH as virgin gas
4High purity is arranged, to metal, water, O
2, CO
2, CO, hydro carbons, type siloxane and PH
3(phosphine), AsH
3(borine), B
2H
6The content of doping agents such as (arsines) has and strict restriction, particularly PH
3, AsH
3, B
2H
6Because chemical property and silane is close and content is lower, also remarkable to the silane The properties, so PH
3, AsH
3, B
2H
6Removal to SiH
4Purification seem particularly important.This just need be to product SiH
4Carry out refinement treatment, in the removal of these impurity, refining SiH in the industry
4The main technology that adopts has absorption method, cold method, rectification method etc., can also be their combination.
Cold method, rectification method can carry out roughing out to silane, remove SiH
4Middle PH
3, AsH
3, B
2H
6Make it reach ppb rank or low levels more Deng trace impurity, adopt absorption method mostly.And the refining silane of absorption method adopts sorbent materials such as gac, molecular sieve, silica gel mostly, utilizes its physical adsorption performance to adsorb the PH in the silane
3, AsH
3, B
2H
6Deng gas, reach the purpose of refining silane.
As utilizing A type and X type zeolite among the patent US2971607, adsorb AsH through selective adsorption
3, PH
3, B
2H
6, service temperature is preferably between-50 ℃ to-100 ℃ generally below 0 ℃.Propose among the US3019087, remove SiH with metal catalyst
4In BH
3, these metal catalysts comprise iron, cobalt, palladium, the blade of a sword, copper and silver, the most handy catalyzer nickel and platinum.In the reaction chamber of metal catalyst is housed at 0 to 100 ℃, 50mm under the pressure of 760mm mercury slug, removal of impurities silane.Mention among the US4554141 and utilize zeolite purification silane to carry out at low temperatures, because more than 30 ℃, silane can react with the aluminosilicate structure of zeolite.Also mention among the US4976944 with zeolite A type and the absorption of X type and remove SiH
4In AsH
3, PH
3, the shortcoming of this method is that the efficient of removal of impurities is low, if obtain high-purity SiH
4, will be repeatedly with SiH
4Gas is through zeolite, like this at SiH
4Each through SiH in the process of zeolite
4Can be lost by zeolite adsorption.
Above method is utilized the physisorption of sorbent materials such as molecular sieve, gac, and this requires adsorption process under lower temperature, to carry out, and in industry, is difficult to realize.In addition, the aluminosilicate structure of molecular sieve is prone to and SiH
4Have an effect and cause the loss of silane.And the adsorbent of molecular sieve of modification, because the sieve particle degree is bigger, the activeconstituents of modification can only get into the top layer; Active component content is lower; Clearance to minor component is lower, is difficult to reach the requirement that minor component is removed, and its aluminosilicate structure causes the loss problem of silane too.
Summary of the invention
The technical problem that the present invention solves is that the trace impurity removal effect in the prior art silane is undesirable, and the spy provides the method that trace impurity is removed in a kind of new silane.
The present invention provides the removal method of trace impurity in a kind of silane, comprises the employing large pores cation exchange resin, and said large pores cation exchange resin is carried out modification; Large pores cation exchange resin after the modification is packed in the adsorption tower, after purging deoxygenation, silane gas is passed through.
The present invention adopts large pores cation exchange resin as adsorbing agent carrier, utilizes the strong characteristics of physical adsorption ability such as its granularity is little, epigranular, the aperture is big, specific surface area is big; Particularly it is carried out the cationic exchange modification, the chemisorption performance that active cation had of utilizing large pores cation exchange resin to have is optionally removed the B in the silane
2H
6, PH
3And AsH
3Deng minor component, make each component concentration reduce to 0.5 * 10
-9Below, reach the request for utilization of electronics and semicon industry to high purity silane.In addition, the present invention has utilized the physical adsorption performance of large pores cation exchange resin and chemisorption performance keying action to remove the trace impurity in the silane simultaneously, can under normal temperature and pressure conditions, significantly remove the trace impurity in the silane.
Description of drawings
Fig. 1 is an impurity removal process schematic flow sheet in a kind of silane that adopts in the specific embodiment of the invention.
Embodiment
Specify particular content of the present invention below in conjunction with embodiment of the present invention and Figure of description.
The present invention provides the removal method of trace impurity in a kind of silane, comprises the employing large pores cation exchange resin, and said large pores cation exchange resin is carried out modification; Large pores cation exchange resin after the modification is packed in the adsorption tower, after purging deoxygenation, silane gas is passed through.The macroporous type acidic cation-exchange resin is a kind of ion exchange resin that has the pore structure in resin particle inside; This resinoid pore from tens dusts to dusts up to ten thousand; Specific surface area can reach every gram hundreds of square metre; It has skeleton structures such as vinylbenzene or vinylformic acid, on skeleton structure, has the group that can supply exchange, as-SO
3H ,-COOH ,-OH etc., its physical adsorption ability effect is remarkable.And, utilize its selective chemical adsorption and physisorption to combine again through large pores cation exchange resin being carried out modification, remove the B in the silane
2H
6, PH
3And AsH
3Deng minor component, can make each component concentration reduce to 0.5 * 10
-9Below, reach the request for utilization of electronics and semicon industry to high purity silane.
Said large pores cation exchange resin is carried out the method for modification; The preferred employing comprise, under 20-80 ℃ of condition, large pores cation exchange resin is immersed in carries out ion exchange reaction 12-36h in the metal salt solution; Reaction finishes the back and washes with high purity water; Under 60-100 ℃, dry 24-48h with vacuum drying oven again, send into 50-150 ℃ nitrogen toward vacuum drying oven then, slowly large pores cation exchange resin is taken out in the cooling back.The present invention utilizes the powerful CEC of Zeo-karb; Use organic or inorganic metal salt solution to carry out ion exchange with it; Let the metallic cation active constituent loading to resin, the large pores cation exchange resin of processing modification is as silane removal of impurities sorbent material.
Said metal salt solution preferably contains Cr from comprising
3+, Fe
3+, Co
2+, Ni
2+, Pb
2+, Cd
2+, Mn
2+, Cu
2+, Zn
2+, Ag
+In the cationic metal salt one or more for example are selected from Cr (NO
3)
3(chromium nitrate), FeCl
3(iron trichloride), CoCl
2(NSC 51149), Ni (CH
3COO)
2(nickel acetate), Pb (CH
3COO)
2(plumbic acetate), Cd (NO
3)
2(cadmium nitrate), MnCl
2(Manganous chloride tetrahydrate), CuSO
4(copper sulfate), Zn (NO
3)
2(zinc nitrate), AgNO
3In the metal salt solutions such as (Silver Nitrates) one or more.The resin that is adopted can be strongly acidic cation-exchange and weak-type Zeo-karb, and its commutative group can be-SO
3H ,-COOH ,-OH ,-NHR ,-NR
2,-NH
2Deng.Said large pores cation exchange resin is preferably from homemade D001 macroporous type strongly acidic styrene type cation exchange resin; Homemade D111 macroporous type acidulous acrylic acid cation exchange resin; Homemade D113 macroporous type acidulous acrylic acid cation exchange resin; The Amberlite-15 macroporous type strongly acidic styrene type cation exchange resin of Dow Chemical company; In the Amberlite IRC-84 macroporous type acidulous acrylic acid cation exchange resin of Dow Chemical company one or more.
(annotate: a lot of at home places of the macroporous ion-exchange resin of domestic brand can both have been bought, such as the Hebei province's Langfang City New Times chemical building material ltd that mentions among the embodiment.In addition; The model of home-made IX product is formed with three Arabic numeral, the classification of the first bit digital representative products, and second-order digit is represented the difference of skeleton; The 3rd bit digital is the difference of SN in order to difference gene, linking agent etc., and macroporous ion-exchange resin adds " D " before model.The meaning of first, second bit digital is seen table 1.)
The meaning of one in the table 1 resin model, binary digit
| Code name | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
| Specific name | Strongly-acid | Slightly acidic | Strong basicity | Weakly alkaline | Sting closing property | Both sexes | Oxidation-reduction quality |
| The skeleton title | Polystyrene | Acrylic acid series | Acetic acid system | Epoxy system | Vinylpyridine system | Urea aldehyde system | Vinyl chloride |
Method of the present invention is further preferred; Adopt two kinds or two or more large pores cation exchange resins, and it is carried out modification, large pores cation exchange resin after the modification is packed into respectively in the different adsorption towers; After purging deoxygenation, silane gas is successively passed through successively.Concrete working method can be that two kinds or two or more large pores cation exchange resins are packed into the different adsorption tower respectively, again with the adsorption tower system of being tightly connected into successively, silane gas is passed through successively.So, therefore different resin combination is used and to be improved its impurity-eliminating effect because different large pores cation exchange resin is different through selectivity impurities absorbed ion effect after the modification.
Shown in Figure of description 1, shown that a kind of employing comprises the process flow diagram of two cover adsorption towers.Comprise A1 and A2 adsorption tower, 8 valves of K1-8, pipeline 1 connects feed line, and pipeline 2 connects vacuum pump, and pipeline 3 connects chromatographic instrument, and pipeline 4 connects exhaust gas processing device.The modified resin sorbent material for preparing of filling in A1, A2 adsorption tower at first with high pure nitrogen purging system 3-5 time, is driven air in the system away; Open K7, two valves of K8 are taken nitrogen in the system away with vacuum pump; Make system reach certain vacuum tightness, valve-off K7, K8 open valve K1 then; Thick silane gas successively gets into adsorption tower A1, A2 from pipeline 1; Get into exhaust gas processing device or silane gathering systems from pipeline 4, after stable, open valve K4, K6 sends into the chromatogram detector to the silane gas after purifying and detects its purity.If in the time of only need moving single adsorption tower, valve-off K2 opens K3, thick silane gas through adsorption tower A1 after directly entering test macro or gathering system.
Trace impurity removal method is preferably carried out with following condition in the silane of the present invention; Comprise the selection large pores cation exchange resin, under 20-80 ℃ of condition, large pores cation exchange resin is immersed in carries out ion exchange reaction 12-36h in the metal salt solution; Reaction finishes the back and washes with high purity water; Dry 24-48h with vacuum drying oven at 60-100 ℃ again, send into 50-150 ℃ nitrogen toward vacuum drying oven then, slowly cooling back taking-up large pores cation exchange resin; Zeo-karb after the modification is packed in the adsorption tower, and loading height is 50～500mm, and whole adsorption tower and some valves form impurity removed system; At-20～50 ℃, pressure is under 50～300kPa condition, with high pure nitrogen purging system 3-5 time, drives air in the system away, feeds silane gas again and carries out removal of impurities.
Embodiment 1
(1) large pores cation exchange resin modification
With home-made D001 macroporous type strongly acidic styrene type cation exchange resin (Hebei province's Langfang City New Times chemical building material ltd), under 60 ℃ at the CuSO of 1.5mol/L
4Soak 12h in the aqueous solution; In ion exchange column, wash 0.5h with high purity water then, baking 4h removes most of moisture in 80 ℃ of convection oven, move into then 80 ℃ ,-keep 24h to remove the micro-moisture in the resin in the vacuum drying oven of 0.1MPa; Feed behind 80 ℃ the nitrogen slowly cooling vacuum baking oven again; Take out resin-sealed subsequent use after the modification, demarcate and be sorbent material a, reach 15% through the mass percent of its Cu of test in resin.
(2) silane removal of impurities
The silane source of the gas is come out from generate reactor; Precooling through-80 ℃ separates most low-boiling point material; The mass percent of analyzing wherein B, P, As is respectively 4.2ppb, 5.3ppb, 2.0ppb, uses sorbent material a to remove B, P, As in the silane then at normal temperatures and pressures.
Use single tower absorbing process, sorbent material is loaded among the adsorption tower A1, adsorption tower A2 emptying (like Figure of description 1): when using sorbent material a, the mass percent of B, P, As is respectively 0.28ppb, 0.25ppb, 0.2ppb in the silane after the removal of impurities.
Embodiment 2
(1) large pores cation exchange resin modification
With home-made D111 macroporous type acidulous acrylic acid cation exchange resin (Hebei province's Langfang City New Times chemical building material ltd), under 80 ℃ at the AgNO of 1.0mol/L
3Soak 24h in the aqueous solution, in ion exchange column, wash 1h then with high purity water; Baking 4h removes most of moisture in 100 ℃ of convection oven; Move into then 100 ℃ ,-keep 24h to remove the micro-moisture in the resin in the vacuum drying oven of 0.1MPa, feed behind 100 ℃ the nitrogen slowly cooling vacuum baking oven again, take out resin-sealed subsequent use after the modification; Demarcate and be to reach 13% through the mass percent of its Ag of test in resin by sorbent material b.
(2) silane removal of impurities
The silane source of the gas is come out from generate reactor; Precooling through-80 ℃ separates most low-boiling point material; The mass percent of analyzing wherein B, P, As is respectively 4.2ppb, 5.3ppb, 2.0ppb, uses sorbent material b to remove B, P, As in the silane then at normal temperatures and pressures.
Use single tower absorbing process, sorbent material is loaded among the adsorption tower A1, adsorption tower A2 emptying (like Figure of description 1): when using sorbent material b, the mass percent of B, P, As is respectively 0.4ppb, 0.25ppb, 0.14ppb in the silane after the removal of impurities.
Embodiment 3
(1) large pores cation exchange resin modification
The Amberlite-15 type strongly acidic styrene type cation exchange resin that LG-DOW company is produced, under 80 ℃ at the CuSO of 1.0mol/L
4Soak 12h in the aqueous solution, then in ion exchange column with high-purity flushing 0.5h, baking 4h stable curing in 80 ℃ of convection oven, then under 80 ℃ at the AgNO of 0.75mol/L
3Soak 12h in the aqueous solution, in ion exchange column, wash 1h, remove most of moisture with baking 4h in 100 ℃ of convection oven with high purity water; Move into then 100 ℃ ,-keep 24h to remove the micro-moisture in the resin in the vacuum drying oven of 0.1MPa; Feed behind 100 ℃ the nitrogen slowly cooling vacuum baking oven again, take out resin-sealed subsequent use after the modification, demarcate and be sorbent material c; Reach 9.5% through the mass percent of its Cu of test in resin, the mass percent of Ag in resin reaches 8%.
(2) silane removal of impurities
The silane source of the gas is come out from generate reactor; Precooling through-80 ℃ separates most low-boiling point material; The mass percent of analyzing wherein B, P, As is respectively 4.5ppb, 5.2ppb, 2.1ppb, uses sorbent material c to remove B, P, As in the silane then at normal temperatures and pressures.
Use single tower absorbing process, sorbent material is loaded among the adsorption tower A1, adsorption tower A2 emptying (like Figure of description 1): when using sorbent material c, the mass percent of B, P, As has reached 0.07ppb, 0.05ppb, 0.06ppb respectively in the silane after the removal of impurities.
Embodiment 4
(1) large pores cation exchange resin modification
Adopt embodiment 1 and embodiment 2 same procedure to prepare sorbent material a and sorbent material b.
(2) silane removal of impurities
The silane source of the gas is come out from generate reactor; Precooling through-80 ℃ separates most low-boiling point material; The mass percent of analyzing wherein B, P, As is respectively 4.5ppb, 5.2ppb, 2.1ppb, uses sorbent material a and sorbent material b to remove B, P, As in the silane then at normal temperatures and pressures.
Use two adsorption tower absorbing process; Sorbent material a pack among the adsorption tower A1, adsorption tower b packs among the adsorption tower A2; Let silane gas successively get into adsorption tower A1 and adsorption tower A2, the mass percent of the silane gas B after the removal of impurities, P, As is respectively 0.04ppb, 0.03ppb, 0.02ppb.
Table 2 silane gas impurity-eliminating effect
Can find out from the test result of table 2; Trace impurity removal method can make below the 0.5ppb that the content of B in the silane, P, As reduces in the silane provided by the invention; Especially when having adopted two kinds of large pores cation exchange resins, can be reduced to below the 0.05ppb, therefore; Trace impurity removal method has been removed the trace impurity in the silane significantly in the silane provided by the invention, reaches the request for utilization to high purity silane of electronics and semicon industry.
Claims (6)
1. the removal method of trace impurity in the silane comprises the employing large pores cation exchange resin, and said large pores cation exchange resin is carried out modification; Large pores cation exchange resin after the modification is packed in the adsorption tower, after purging deoxygenation, makes silane gas pass through adsorption tower; Wherein, Said large pores cation exchange resin is carried out modification, be included under the 20-80 ℃ of condition, large pores cation exchange resin is immersed in carries out ion exchange reaction 12-36h in the metal salt solution; Reaction finishes post-flush; Under 60-100 ℃, dry 24-48h with vacuum drying oven again, send into 50-150 ℃ nitrogen toward vacuum drying oven then, obtain modified macroporous type Zeo-karb after the cooling.
2. the removal method of trace impurity in the silane according to claim 1, wherein, said metal salt solution is selected from Cr
3+, Fe
3+, Co
2+, Ni
2+, Pb
2+, Cd
2+, Mn
2+, Cu
2+, Zn
2+, Ag
+In the cationic metal salt one or more.
3. the removal method of trace impurity in the silane according to claim 1 and 2; Wherein, said large pores cation exchange resin is selected from one or more in D001 macroporous type strongly acidic styrene type cation exchange resin, D111 macroporous type acidulous acrylic acid cation exchange resin, D113 macroporous type acidulous acrylic acid cation exchange resin, Amberlite-15 macroporous type strongly acidic styrene type cation exchange resin, the Amberlite IRC-84 macroporous type acidulous acrylic acid cation exchange resin.
4. the removal method of trace impurity in the silane according to claim 1; Wherein, Two or more large pores cation exchange resins are carried out modification; Large pores cation exchange resin after the modification is packed into respectively in the different adsorption towers, after purging deoxygenation, makes silane gas successively pass through adsorption tower.
5. the removal method of trace impurity in the silane according to claim 1 wherein, is packed into the Zeo-karb after the modification in the adsorption tower, and said loading height is 50～500mm; Is under 50～300kPa condition in temperature for-20～50 ℃, pressure, purges adsorption tower 3-5 time with high pure nitrogen, feeds silane gas again and carries out removal of impurities.
6. the removal method of trace impurity in the silane according to claim 1 wherein, is packed into the Zeo-karb after the modification in the adsorption tower, and said loading height is 50～500mm; Is under 50～300kPa condition in temperature for-20～50 ℃, pressure, purges adsorption tower 3-5 time with high pure nitrogen, and feeding silane gas again carries out removal of impurities; Said metal salt solution is selected from Cr
3+, Fe
3+, Co
2+, Ni
2+, Pb
2+, Cd
2+, Mn
2+, Cu
2+, Zn
2+, Ag
+In the cationic metal salt one or more; Said large pores cation exchange resin is selected from one or more in D001 macroporous type strongly acidic styrene type cation exchange resin, D111 macroporous type acidulous acrylic acid cation exchange resin, D113 macroporous type acidulous acrylic acid cation exchange resin, Amberlite-15 macroporous type strongly acidic styrene type cation exchange resin, the Amberlite IRC-84 macroporous type acidulous acrylic acid cation exchange resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101092067A CN101987730B (en) | 2009-07-30 | 2009-07-30 | Method for removing trace impurities in silicane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101092067A CN101987730B (en) | 2009-07-30 | 2009-07-30 | Method for removing trace impurities in silicane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101987730A CN101987730A (en) | 2011-03-23 |
| CN101987730B true CN101987730B (en) | 2012-08-01 |
Family
ID=43744549
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009101092067A Expired - Fee Related CN101987730B (en) | 2009-07-30 | 2009-07-30 | Method for removing trace impurities in silicane |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101987730B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4532120A (en) * | 1983-12-28 | 1985-07-30 | Ethyl Corporation | Silane purification process |
| EP0299488A2 (en) * | 1987-07-15 | 1989-01-18 | Hercules Incorporated | Removal of arsine and phosphine from silane |
| CN101327930A (en) * | 2008-07-18 | 2008-12-24 | 浙江理工大学 | Use of anhydrous magnesium chloride in silane purification |
-
2009
- 2009-07-30 CN CN2009101092067A patent/CN101987730B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4532120A (en) * | 1983-12-28 | 1985-07-30 | Ethyl Corporation | Silane purification process |
| EP0299488A2 (en) * | 1987-07-15 | 1989-01-18 | Hercules Incorporated | Removal of arsine and phosphine from silane |
| CN101327930A (en) * | 2008-07-18 | 2008-12-24 | 浙江理工大学 | Use of anhydrous magnesium chloride in silane purification |
Non-Patent Citations (1)
| Title |
|---|
| JP特表2003-501340A 2003.01.14 |
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|---|---|
| CN101987730A (en) | 2011-03-23 |
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