CN201313954Y - Reducing furnace for preparing polycrystalline silicon - Google Patents
Reducing furnace for preparing polycrystalline silicon Download PDFInfo
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- CN201313954Y CN201313954Y CNU2008201233511U CN200820123351U CN201313954Y CN 201313954 Y CN201313954 Y CN 201313954Y CN U2008201233511 U CNU2008201233511 U CN U2008201233511U CN 200820123351 U CN200820123351 U CN 200820123351U CN 201313954 Y CN201313954 Y CN 201313954Y
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- reduction furnace
- inlet mouth
- chassis
- venting port
- polycrystalline silicon
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Abstract
The utility model relates to a reducing furnace for preparing polycrystalline silicon, which comprises an outer shell, an inner shell, a chassis, silicon mandrils, a cooling water-circulating unit, an air inlet and an exhaust outlet, wherein the air inlet and the exhaust outlet are arranged on the chassis. The reducing furnace has the following characteristics: an air inlet is arranged on the upper side of the reducing furnace, and the air inlet and the exhaust outlet are independently arranged on the chassis and/or the top or combined in the form of a double-layered concentric sleeve. The reducing furnace can improve the turbulent flow of feed gas, reduce or eliminate the boundary layer effect and reduce the formation of structural interlayers, consequently, the polycrystalline silicon produced by reduction can be precipitated thickly and uniformly, the growth quality of the polycrystalline silicon can be improved, meanwhile, the consumption of raw material can be reduced, the conversion rate of raw material can be increased, and productivity can be increased.
Description
Technical field
The utility model relates to field of polysilicon production, particularly relates to a kind of reduction furnace that is used for production of polysilicon.
Background technology
Polysilicon is a main raw material of making products such as unicircuit substrate, solar cell.Polysilicon can be used to prepare silicon single crystal, and its deep processed product is widely used in the semi-conductor industry, as the base mateiral of devices such as artificial intelligence, control automatically, information processing, opto-electronic conversion.Simultaneously, because energy dilemma and requirement on environmental protection, the whole world just utilizes renewable energy source at active development.Sun power is the most noticeable in the described renewable energy source, because its cleaning, safety, aboundresources.A kind of method of utilizing sun power is for to be electric energy by photovoltaic effect with conversion of solar energy.Silicon solar cell is the device based on photovoltaic effect that the most generally adopts.Because the development of semi-conductor industry and solar cell, the demand of high-purity polycrystalline silicon is constantly increased.
Polysilicon can be divided into solar level, electronic-grade by the purity classification.The polysilicon of solar level and electronic-grade can be prepared by metallurgical grade silicon, its basic skills is that solid-state metallurgical grade silicon is converted into certain liquefied compound that exists in the temperature range that allows, for example metallurgical grade silicon is converted into chlorosilane, then it being carried out the degree of depth with the highly efficient distilling method purifies so that remove wherein impurity, with reductive agents such as hydrogen the chlorosilane of purifying is reduced to elemental silicon subsequently, wherein elemental silicon is the form of polysilicon.
The hydrogen reduction of trichlorosilane is that company of Siemens (Siemens) invented in 1954, claims Siemens Method again, is the high-purity polycrystalline silicon technology of preparing that extensively adopts.Its chemical equation is:
Si+3HCl→SiHCl3+H2 (1)
This reaction also generates by product such as silicon tetrachloride, dichloro hydrogen silicon (SiH2Cl2) etc. except generation is used to produce the trichlorosilane of high-purity polycrystalline silicon.The product mixtures of above-mentioned reaction obtains the extremely low high-purity trichlorosilane logistics of foreign matter content through slightly heating up in a steamer and rectification process.Then, reduction reaction takes place in this high-purity trichlorosilane logistics and High Purity Hydrogen on the high-purity polycrystalline silicon core of heating, and by chemical vapour deposition, the new high-purity polycrystalline silicon of generation is deposited on the silicon core.Its reaction formula is:
2SiHCl3+H2→Si+2HCl+SiCl4+H2 (2)
Reduction furnace is a main equipment in the above-mentioned Siemens process polycrystalline silicon production technique, it is a vertical bell reactor (reduction furnace), comprise outer casing, internal layer shell, chassis, silicon plug, cooling water circulating device, and the inlet mouth, the venting port that are arranged on the place, chassis.Trichlorosilane/hydrogen mixed gas is introduced reduction furnace from the inlet mouth that is arranged on the reduction furnace chassis, and waste gas is discharged from the venting port that is arranged on the reduction furnace chassis.
In the deposition process, silicon rod is thinner in the early stage for silicon rod, and it is less to deposit needed gas volume.Because the structure of reduction furnace self, air inlet is from the bottom, the tail gas outlet is also at furnace bottom, simultaneously because the structure of inlet mouth, cause trichlorosilane/hydrogen mixed gas to be difficult to arrive bell reduction furnace top, cause in stagnant area of existence, reduction furnace top, and gas is difficult to form uniform distribution preferably in reduction furnace.
Silicon rod is in mid-term reduce deposition process, because there is the stagnant area in the reduction furnace top, the unstripped gas that newly advances can not arrive the reaction zone at bell jar top, and makes the top retained gas can not enter the recycle system, causes stove inner top temperature height.And along with the increase of silicon rod diameter, the required raw material that reduces also must constantly increase thereupon, and top feed reaction tolerance is just inadequate especially like this.With the carrying out of deposition reaction, the silicon rod diameter increases, the turbulent flows variation, the effect of boundary layer of deposition carrier surface strengthens, and makes the silicon rod growth inhomogeneous, easily forms the structure interlayer simultaneously, crystal grain is with loose, coarse form deposition, and then develop into plethora, and wherein often being mingled with bubble and impurity, difficult the corrosion through acid treatment removed, when the pulling monocrystal melt, make the molten silicon liquid fluctuating, even the splash and the silicon jumping of melt silicon occur, make crystal pulling be difficult to go on when serious.The polycrystalline silicon growth at position, silicon rod upper end is slow and loose not fine and close, forms top and slightly dredges, and the bottom is close and real.Follow-up corrosion cleaning, crystal pulling operation are caused difficulty.
For addressing the above problem, thereby prior art discloses the method that adopts the pressure that increases mixed gas to improve jet velocity and solves, but the shortcoming of this method is: when jet velocity increases hour, the material skewness can't effectively be eliminated effect of boundary layer; When increasing greatly, the excessive resistance at spout place can cause pressure drop excessive, and variable valve is exerted an influence, and can't accurately regulate flow, deposition uniformity is descended, and jet velocity is excessive, can impact to crossbeam place silicon core, influences current circuit.
In addition, disclose as Chinese patent CN201105992Y and to have utilized regulated valve that each group spout is carried out the method for the incompatible adjusting flow of switches set, but the weak point of this device is that the turbulent flows raising degree of mixed gas is limited, the gas distribution of whole reduction furnace is still even inadequately, and the combination of various switches makes the technology of production operation be tending towards complicated easily.
Chinese patent CN1415927A discloses the long-pending nozzle of rotatable variable cross-section that utilizes servomotor to control, to satisfy the processing requirement of different growth phases, but being facility investment, the weak point of this kind device increases, the operating process complexity, and owing to adopted complicated driving and drive mechanism, increase the trouble spot, and system reliability descends.
Chinese patent CN1982213A discloses the nozzle that has extension, and the angle between extension and the nozzle is 90 degree, equidistantly on the extension is distributed with a plurality of air outlets.But the weak point of this kind device is the angle of 90 degree significantly reduces the flow velocity of mixed gas, and the reaction zone that mixed gas is effectively arrived the reduction furnace top has bigger negative effect.
The utility model content
The purpose of this utility model is the deficiency that overcomes in the above-mentioned processing unit, a kind of reduction furnace is provided, this reduction furnace comprises outer casing, internal layer shell, is positioned at chassis, silicon core, the cooling water circulating device of described reduction furnace bottom, is arranged on bottom inlet mouth and bottom venting port that the chassis is located, is provided with at least one top inlet mouth on the top of described reduction furnace.Owing to set up inlet mouth separately at reduction furnace chassis, top, make the unstripped gas can be with parallel, countercurrent flow, effectively strengthened the turbulent flows of unstripped gas, reduce the formation of structure interlayer, make crystal grain with fine and close, uniform form deposition, and need not to increase jet velocity and injection flow, can also reduce supplies consumption, improve the utilization ratio of unstripped gas, make gain in yield.
Adopt the utility model effectively to strengthen the turbulent flows of feeding gas, reduce, eliminated effect of boundary layer, make crystal grain with fine and close, uniform form deposition, improve the texture quality of silicon rod, satisfy the needs of major diameter silicon rod growth, can obtain major diameter, internal structure densification, smooth surface and be dimmed polycrystalline silicon rod.
Description of drawings
Fig. 1 is a preferred embodiment of the present utility model, and its middle and upper part inlet mouth is arranged on reduction furnace top arc part.
Fig. 2 is another preferred embodiment of the present utility model, and wherein the position more than the silicon plug of reduction furnace top is provided with protective shield, and top inlet mouth and upper air vent are arranged on the protective shield.Top inlet mouth and upper air vent adopt the concentric bilayer sleeve pipe.
Fig. 3 is a concentric bilayer telescopic sectional view, and the inlet mouth position extends beyond the venting port position among Fig. 3 a, and the inlet mouth position is concordant with the venting port position among Fig. 3 b.
Fig. 4 is an one-piece construction synoptic diagram of the present utility model, wherein shows the pipeline variable valve and the diffuser of reduction furnace outside, and can see two top inlet mouths at the protective shield place.
Reference numeral: outer casing 1, internal layer shell 2, silicon core 3, visor 4, chassis 5, graphite strut member 6, protective shield 7, bottom inlet mouth 8, bottom venting port 9, cooling water inlet pipe 10, water coolant water shoot 11, variable valve 12, unstripped gas diffuser 13, pipeline 14, flange 15, concentric reducer 16, top inlet mouth 18, upper air vent 19.
Embodiment
Further specify of the present utility model below in conjunction with accompanying drawing.
Reduction furnace comprises outer casing 1, internal layer shell 2, silicon core 3, cooling water circulating device and chassis 5.This chassis 5 is provided with bottom inlet mouth 8 and bottom venting port 9.Cooling water circulating device comprises cooling water inlet pipe 10 and water coolant water shoot 11.For realizing target of the present utility model, the technical solution adopted in the utility model is, except bottom inlet mouth 8, at least one top inlet mouth 18 is set at the top of reduction furnace also, makes reduction furnace chassis and top place all be provided with inlet mouth 8,18; In addition, also at least one upper air vent 19 can be set at the top of reduction furnace.
A preferred embodiment wherein is provided with a top inlet mouth 18 at arc part place, reduction furnace top as shown in Figure 1.Be arranged on two the bottom inlet mouths 8 and a bottom venting port 9 at place, chassis as can see from Figure 1, this bottom venting port 9 is located at the center chassis place.Top inlet mouth 18 is connected with diffuser through pipeline respectively with bottom inlet mouth 8, and this pipeline is provided with the variable valve 12 of the flow of control bottom and top inlet mouth.At the top and two places, chassis of reduction furnace, simultaneously via top inlet mouth 18 and 8 air inlets of bottom inlet mouth, the parallel countercurrent flow of unstripped gas (see among the figure shown in the arrow) makes crystal grain with fine and close, form deposition uniformly, grows the fine and closely woven polycrystalline silicon rod of structure.And need not to increase jet velocity and injection flow, and reduce supplies consumption, improve the utilization ratio of unstripped gas, make gain in yield.
For the ease of top inlet mouth 18 is installed, can with the upper part protective shield 7 be set at the top of reduction furnace silicon core, as shown in Figure 2.Preferably, the distance between protective shield 7 and the reduction furnace arc top is less than 1/3rd of reduction furnace whole height, and protective shield is identical with the cross section of reduction furnace.Can make with the material identical or other high temperature materials with the reduction furnace internal layer shell, can with the welding or or other known methods be connected with former stove internal layer shell.Owing to be provided with protective shield, be more convenient on protective shield, being provided with the top inlet mouth.Simultaneously, also upper air vent can be set on protective shield.
In the embodiment of Fig. 2, in protective shield 7, be provided with a top inlet mouth 18 and a upper air vent 19.Be arranged on four the bottom inlet mouths 8 and a bottom venting port 9 at place, chassis as can see from Figure 2, this bottom venting port 9 is located at the center chassis place.
Further,, improve the resistance to air loss of reduction furnace, can adopt the form of concentric tubes to form paired inlet mouth and venting port as top inlet mouth 18 among Fig. 2 and upper air vent 19 for reducing the reduction furnace number of openings.For example, every suit concentric tubes can form an inlet mouth and a venting port.
Fig. 3 shows the concentric bilayer telescopic sectional view that forms inlet mouth and venting port, can form inlet mouth 8,18 by managing the inner channel that is limited in this concentric bilayer telescopic, the outer passage that is limited between interior pipe of this concentric bilayer telescopic and the outer tube can form venting port 9,19.The position of this inlet mouth 8,18 both can extend beyond the position (shown in Fig. 3 a) of venting port 9,19, also can flush (shown in Fig. 3 b) with the position of this venting port 9,19.
Such concentric tubes both can be arranged on the top (for example protective shield place) of reduction furnace as shown in Figure 2, to form a pair of top inlet mouth 18 and venting port 19; Also can be arranged on chassis 5 and sentence formation a pair of bottom inlet mouth and venting port, to substitute independent bottom inlet mouth 8 and the venting port 9 that is provided with shown in the current accompanying drawing.Certainly, also can use such concentric tubes simultaneously on chassis and reduction furnace top.
In order further to observe and monitor the situation of carrying out of reduction furnace reaction, can further install visor 4 additional as depicted in figs. 1 and 2 in side, reduction furnace furnace wall.For the silicon core is better combined with the chassis, as depicted in figs. 1 and 2 graphite strut member 6 can be set between silicon core and chassis further.
Claims (11)
1. reduction furnace that is used to prepare polysilicon, it comprises outer casing, internal layer shell, is positioned at chassis, silicon core, the cooling water circulating device of described reduction furnace bottom, is arranged on bottom inlet mouth and bottom venting port that the chassis is located, it is characterized in that, be provided with at least one top inlet mouth on the top of described reduction furnace.
2. reduction furnace as claimed in claim 1 is characterized in that, is provided with at least one upper air vent on the top of described reduction furnace.
3. reduction furnace as claimed in claim 1 is characterized in that, described top inlet mouth is arranged on arc part place, reduction furnace top.
4. reduction furnace as claimed in claim 1 or 2 is characterized in that, on reduction furnace top and more than the silicon core the position protective shield is set, described top inlet mouth is arranged in the protective shield.
5. reduction furnace as claimed in claim 4 is characterized in that described upper air vent is arranged on the described protective shield.
6. reduction furnace as claimed in claim 2, it is characterized in that, form with concentric tubes forms paired top inlet mouth and upper air vent and/or paired bottom inlet mouth and bottom venting port, and the inner channel of this concentric tubes is an inlet mouth, and outer passage is the air outlet.
7. reduction furnace as claimed in claim 6 is characterized in that, the position of inlet mouth extends beyond the position of venting port.
8. reduction furnace as claimed in claim 6 is characterized in that the position of inlet mouth is concordant with the position of venting port.
9. reduction furnace as claimed in claim 1 or 2 is characterized in that, in described reduction furnace, is provided with the graphite strut member below the silicon core.
10. reduction furnace as claimed in claim 1 or 2 is characterized in that, the outer casing and the internal layer shell of described reduction furnace are provided with visor.
11. reduction furnace as claimed in claim 7 is characterized in that, described bottom is connected with diffuser (13) through pipeline (14) respectively with the top inlet mouth, and is provided with the variable valve (12) of the flow that can independently control bottom and top inlet mouth outside reduction furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201233511U CN201313954Y (en) | 2008-11-03 | 2008-11-03 | Reducing furnace for preparing polycrystalline silicon |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201233511U CN201313954Y (en) | 2008-11-03 | 2008-11-03 | Reducing furnace for preparing polycrystalline silicon |
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| CN201313954Y true CN201313954Y (en) | 2009-09-23 |
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| CNU2008201233511U Expired - Fee Related CN201313954Y (en) | 2008-11-03 | 2008-11-03 | Reducing furnace for preparing polycrystalline silicon |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101837977A (en) * | 2010-03-12 | 2010-09-22 | 江苏中能硅业科技发展有限公司 | Method and equipment for producing elementary silicon |
| CN101724895B (en) * | 2009-12-17 | 2011-12-21 | 江苏中能硅业科技发展有限公司 | Production process of polycrystalline silicon |
| CN101759184B (en) * | 2009-09-30 | 2012-05-30 | 江苏中能硅业科技发展有限公司 | System for making polysilicon with assistance of hydrogen plasmas and method therefor |
| CN102674360A (en) * | 2012-05-09 | 2012-09-19 | 天津大学 | Heat insulation inner liner of energy-saving polycrystalline silicon reduction furnace provided with polycrystalline silicon slice, and implementation method thereof |
| CN101748482B (en) * | 2008-12-19 | 2013-02-13 | 江苏中能硅业科技发展有限公司 | Improvement method for the preparation of highly dense structure polycrystalline silicon and the device thereof |
| DE102013204730A1 (en) | 2013-03-18 | 2014-09-18 | Wacker Chemie Ag | Method of depositing polycrystalline silicon |
| CN104150484A (en) * | 2013-05-13 | 2014-11-19 | 苏州晶科新能源装备科技有限公司 | Enclosed type high purity metal silicon reduction furnace |
| CN105579395A (en) * | 2013-09-23 | 2016-05-11 | 瓦克化学股份公司 | Process for producing polycrystalline silicon |
| CN106927466A (en) * | 2017-04-05 | 2017-07-07 | 亚洲硅业（青海）有限公司 | A kind of 48 pairs of rod reducing furnace body structures |
| CN108821235A (en) * | 2018-08-31 | 2018-11-16 | 深圳市雄韬电源科技股份有限公司 | The controllable continuous hydrolysis hydrogen generating system of hydrogen production rate |
| CN115072726A (en) * | 2022-05-17 | 2022-09-20 | 卫敏 | Polycrystalline silicon reduction furnace |
| CN117247019A (en) * | 2023-11-17 | 2023-12-19 | 内蒙古耀煜新能源科技有限公司 | Reducing furnace control instrument device for producing based on polycrystalline silicon |
-
2008
- 2008-11-03 CN CNU2008201233511U patent/CN201313954Y/en not_active Expired - Fee Related
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101748482B (en) * | 2008-12-19 | 2013-02-13 | 江苏中能硅业科技发展有限公司 | Improvement method for the preparation of highly dense structure polycrystalline silicon and the device thereof |
| CN101759184B (en) * | 2009-09-30 | 2012-05-30 | 江苏中能硅业科技发展有限公司 | System for making polysilicon with assistance of hydrogen plasmas and method therefor |
| CN101724895B (en) * | 2009-12-17 | 2011-12-21 | 江苏中能硅业科技发展有限公司 | Production process of polycrystalline silicon |
| CN101837977A (en) * | 2010-03-12 | 2010-09-22 | 江苏中能硅业科技发展有限公司 | Method and equipment for producing elementary silicon |
| CN101837977B (en) * | 2010-03-12 | 2013-02-13 | 江苏中能硅业科技发展有限公司 | Method and equipment for producing elementary silicon |
| CN102674360A (en) * | 2012-05-09 | 2012-09-19 | 天津大学 | Heat insulation inner liner of energy-saving polycrystalline silicon reduction furnace provided with polycrystalline silicon slice, and implementation method thereof |
| CN102674360B (en) * | 2012-05-09 | 2014-05-21 | 天津大学 | Heat insulation inner liner of energy-saving polycrystalline silicon reduction furnace provided with polycrystalline silicon slice, and implementation method thereof |
| WO2014146876A1 (en) | 2013-03-18 | 2014-09-25 | Wacker Chemie Ag | Polycrystalline silicon deposition method |
| DE102013204730A1 (en) | 2013-03-18 | 2014-09-18 | Wacker Chemie Ag | Method of depositing polycrystalline silicon |
| US9738530B2 (en) | 2013-03-18 | 2017-08-22 | Wacker Chemie Ag | Polycrystalline silicon deposition method |
| CN104150484A (en) * | 2013-05-13 | 2014-11-19 | 苏州晶科新能源装备科技有限公司 | Enclosed type high purity metal silicon reduction furnace |
| CN105579395A (en) * | 2013-09-23 | 2016-05-11 | 瓦克化学股份公司 | Process for producing polycrystalline silicon |
| US9738531B2 (en) | 2013-09-23 | 2017-08-22 | Wacker Chemie Ag | Process for producing polycrystalline silicon |
| CN105579395B (en) * | 2013-09-23 | 2018-01-26 | 瓦克化学股份公司 | method for producing polysilicon |
| CN106927466A (en) * | 2017-04-05 | 2017-07-07 | 亚洲硅业（青海）有限公司 | A kind of 48 pairs of rod reducing furnace body structures |
| CN108821235A (en) * | 2018-08-31 | 2018-11-16 | 深圳市雄韬电源科技股份有限公司 | The controllable continuous hydrolysis hydrogen generating system of hydrogen production rate |
| CN115072726A (en) * | 2022-05-17 | 2022-09-20 | 卫敏 | Polycrystalline silicon reduction furnace |
| CN117247019A (en) * | 2023-11-17 | 2023-12-19 | 内蒙古耀煜新能源科技有限公司 | Reducing furnace control instrument device for producing based on polycrystalline silicon |
| CN117247019B (en) * | 2023-11-17 | 2024-01-23 | 内蒙古耀煜新能源科技有限公司 | Reducing furnace control instrument device for producing based on polycrystalline silicon |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090923 Termination date: 20121103 |