CN202170244U - Polycrystalline silicon reducing furnace - Google Patents
Polycrystalline silicon reducing furnace Download PDFInfo
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- CN202170244U CN202170244U CN 201120164131 CN201120164131U CN202170244U CN 202170244 U CN202170244 U CN 202170244U CN 201120164131 CN201120164131 CN 201120164131 CN 201120164131 U CN201120164131 U CN 201120164131U CN 202170244 U CN202170244 U CN 202170244U
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- polycrystalline silicon
- reducing furnace
- furnace
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Abstract
An embodiment of the utility model discloses a polycrystalline silicon reducing furnace, which comprises a furnace barrel and a bottom plate, wherein the bottom plate is provided with a plurality of pairs of electrodes. The polycrystalline silicon reducing furnace further comprises a thermal insulating layer arranged between the inner wall of the furnace barrel of the polycrystalline silicon reducing furnace and the outermost layer of electrode on the bottom plate. By arranging the thermal insulating layer between the inner wall of the furnace barrel and the outermost layer of electrode on the bottom plate, the polycrystalline silicon reducing furnace stops heat exchange between the inside of the reducing furnace and the furnace wall to some extent, thereby enabling a water clamping sleeve structure to cool the furnace barrel, enabling a thermal field inside the reducing furnace not to be influenced simultaneously, guaranteeing thermal field balance inside the reducing furnace, improving quality of polycrystalline silicon products and enabling thickness of produced polycrystalline silicon rods to be more uniform. Besides, due to the arrangement of the thermal insulating layer, loss of heat in the reducing furnace is reduced, the fact that heat in the reducing furnace is not leaked out is guaranteed, and energy loss of the reducing furnace is reduced to some extent.
Description
Technical field
The utility model relates to polycrystalline silicon production device, more particularly, relates to a kind of polycrystalline silicon reducing furnace.
Background technology
Along with development of science and technology, the development of photovoltaic industry and semi-conductor industry is also more and swifter and more violent, and is therefore also increasing for the demand of the main raw material polysilicon of photovoltaic industry and semi-conductor industry production usefulness.
At present; The method that industry is produced polysilicon has multiple; Wherein hydrogen reduction method is more commonly also claimed Siemens Method, and that uses at present is the improvement Siemens Method more widely; The more traditional siemens's method of Siemens Method of improvement possesses advanced low energy technology, and can effectively recycle SiCl a large amount of in the production process
4, HCl, H
2Deng by product and a large amount of by-product heat energy.
Improvement Siemens Method and traditional siemens ratio juris are similar; Be mainly: with high-purity hydrogen and the reactant of highly purified silicon (being mostly silicon halogenide) as raw material; Be passed into by a certain percentage in the reaction vessel (being polycrystalline silicon reducing furnace), under the environment of HTHP, the reactant of hydrogen reducing silicon; Thereby the formation polysilicon, the polysilicon of formation can be deposited on the silicon core.Along with the continuation of chemical reaction, the polysilicon that is deposited on the silicon core is more and more, gradually the silicon core is all covered, and becomes the rhoptry that an outer wrap polysilicon, is commonly called as silicon rod.Along with proceeding of chemical reaction in the reduction furnace, the radius of silicon rod is increasing, up to reaching predetermined size, promptly stops the chemical reaction in the reduction furnace.
Adopt the improvement Siemens Method to produce in the process of polysilicon; Generally the silicon rod surface temperature in the reduction furnace is maintained the temperature of reaction about 1100 ℃ through the resistive heating; But, just must take necessary sfgd. to the stove tube of reduction furnace because the too high meeting of temperature has certain infringement to the stove tube in the reduction furnace.Method commonly used at present is in the stove tube of reduction furnace, the water jacket structure to be set, and in jacket structured, feeds high-temperature water, takes away the surperficial heat of stove tube through high-temperature water, to reach the purpose that reduces stove tube temperature.
In actual production process, find; After adopting this cooling method; Though the temperature of stove tube has reduced, uneven phenomenon appears in the thickness degree of the polycrystalline silicon rod of in same reduction furnace, producing in same batch, thereby influences the quality of polysilicon product.
The utility model content
The utility model embodiment provides a kind of polycrystalline silicon reducing furnace, has solved the problems of the prior art, has improved the quality of polysilicon product, and the thickness of the polycrystalline silicon rod of producing is more even, and, reduced the loss of reduction furnace energy to a certain extent.
For realizing above-mentioned purpose, the utility model embodiment provides following technical scheme:
A kind of polycrystalline silicon reducing furnace comprises stove tube and chassis, and said chassis is provided with many counter electrode, also comprises: be arranged at the stove tube inwall of said polycrystalline silicon reducing furnace and the thermal insulation layer between the outermost layer electrode on the said chassis.
Preferably, said thermal insulation layer is the drum of up and down break-through.
Preferably, said thermal insulation layer is arranged on the said chassis.
Preferably, has the slit between said thermal insulation layer and said stove tube inwall.
Preferably, said thermal insulation layer is fixed in said stove tube inwall.
Preferably, said thermal insulation layer is processed by one of C/C matrix material, graphite material, sapphire whisker, titanium alloy, stainless steel, stupalith, Incoloy series material.
Preferably, said chassis is provided with equally distributed mixed gas inlet nozzle, and said center chassis is provided with the tail gas venting port.
Compared with prior art, technique scheme has the following advantages:
The polycrystalline silicon reducing furnace that the utility model embodiment provides; Through between the outermost layer electrode on stove tube inwall and the said chassis, being provided with thermal insulation layer, stoped the thermal exchange of reduction furnace inside to a certain extent with twere, make the water jacket structure carry out refrigerative simultaneously to the stove tube; Do not have influence on the inner thermal field of reduction furnace; Promptly the temperature owing to the thermal insulation layer inwall can not reduce because of the cooling of stove tube, thereby the transfer of heat does not take place in the reduction furnace inside that makes the insulation layer coat, thereby has guaranteed that the inner thermal field of reduction furnace is balanced; Improved the quality of polysilicon product, made the thickness of the polycrystalline silicon rod of producing more even.
And, because the setting of thermal insulation layer has reduced the loss of reduction furnace internal heat, guaranteed that the heat in the reduction furnace does not leak, reduced the loss of reduction furnace energy to a certain extent.
Description of drawings
Shown in accompanying drawing, above-mentioned and other purpose, characteristic and the advantage of the utility model will be more clear.Reference numeral identical in whole accompanying drawings is indicated identical part.Painstakingly do not draw accompanying drawing, focus on illustrating the purport of the utility model by physical size equal proportion convergent-divergent.
Fig. 1 is the voltate regulator load synoptic diagram of being connected and being formed by the resistance of a plurality of silicon rods;
Fig. 2 is the structural representation of the disclosed polycrystalline silicon reducing furnace of the utility model embodiment;
Fig. 3 is the chassis structure synoptic diagram of the disclosed polycrystalline silicon reducing furnace of the utility model embodiment;
Fig. 4 is the structural representation of the disclosed polycrystalline silicon reducing furnace of another embodiment of the utility model.
Embodiment
Said as the background technology part, the polycrystalline silicon rod thickness of producing of the prior art is uneven, and the utility model the contriver discover; The reason that this situation occurs is; When adopting water jacket structure cooling reduction furnace stove tube, also having taken away great amount of heat in the reduction furnace, mainly is to make the heat near the reduction furnace inner wall area scatter and disappear serious; Thereby make that the inner thermal field of reduction furnace is even inadequately, and then can't guarantee the even growth of silicon rod.
Concrete, polysilicon reduction operation more is by the control of reduction furnace electrical system, and the major equipment of reduction furnace electrical system is high-power voltate regulator, and the load of voltate regulator is by polycrystalline silicon rod series connection formation pure resistor load R.The effect of voltate regulator is actually carries out a heating to pull-up resistor, and keeps the homo(io)thermism on silicon rod surface, generally remains on about 1100 ℃ of the growth temperatures of polysilicon.As shown in Figure 1, the resistance R that is formed by the resistance R 1 of a plurality of polycrystalline silicon rods, R2, R3......, Rn series connection is the resistance of a variation, mainly is because along with the growth of silicon rod and the rising of self temperature, and the resistance of each silicon rod itself is continuous variation.Generally speaking; The temperature of silicon rod rises to about 1000 ℃ from normal temperature, and diameter is that the resistance of the silicon core of Φ 8mm can drop to tens Ω from hundreds of k Ω, and keeping the silicon rod surface temperature is about 1100 ℃; The diameter of silicon rod is increased to Φ 150mm from Φ 8mm; Silicon rod resistance can drop to tens m Ω from tens Ω, this shows, because silicon rod resistance changes nature on a large scale and can cause that the output voltage of voltate regulator and output current regulating scope have big change.
Characteristics according to the character of above-mentioned real work; Voltate regulator is divided into preheating voltate regulator and reduction voltate regulator; The preheating voltate regulator is heated to from normal temperature 1000 ℃ of processes in the silicon rod temperature and uses; The reduction voltate regulator uses the silicon rod diameter is increased to the process of final diameter from initial size (being generally Φ 7mm-Φ 8mm), and the reduction voltate regulator also is used for keeping the silicon rod surface temperature about 1100 ℃.
If the situation of each silicon rod is the same (being R1=R2=R3=......=Rn) in the resistance that is in series by silicon rod; Then electrical system will be than the temperature that is easier to control each silicon rod surface; But, generally be center annular distribution around the chassis because in the actual production, each silicon rod distribution position on the reduction furnace chassis is different; The silicon rod that has is positioned at ring, and what have is positioned at outer shroud.Simultaneously since a large amount of heats in the reduction furnace taken away by the water coolant in the water jacket structure, thereby make temperature in the reduction furnace inequality of arranging from inside to outside, the axis that is generally with reduction furnace is the center; Temperature from inside to outside reduces gradually, because the temperature on silicon rod surface is different, must cause the resistance of silicon rod different; Promptly occur R1 ≠ R2 ≠ R3 ≠ ... the situation of ≠ Rn, yet, because when heating for silicon rod; Electric current through each silicon rod is the same, according to Q=I
2Rn can know that the mode of taking to switch on is in the silicon rod heat-processed, and the heat that on every silicon rod, produces also is inequality, and resistance is big more, and the heat that produces on the silicon rod is also big more.
Because the variation of temperature gradient is difficult to control and also is difficult to survey in the reduction furnace that causes because of the use of water jacket structure; And the heat that produces because of energising on while every silicon rod is also different; After various factors is taken all factors into consideration; Very difficult control through electrical system all maintains about 1100 ℃ near the temperature the every silicon rod, promptly is difficult to guarantee the equilibrium of thermal field in the reduction furnace, thereby also just is difficult to guarantee the even growth of silicon rod.
In sum, the basic reason that causes that silicon rod can not evenly grow is, owing to adopt water jacket structural defence stove tube; Thereby taken away a large amount of heats in the reduction furnace through the furnace wall, if but the use of cancellation water jacket structure can cause certain infringement to the stove tube again; Therefore, the contriver considers, if can be under the situation of using the water jacket structure; Can also avoid so take away a large amount of heats in the reduction furnace; Can solve the uneven problem of the silicon rod thickness produced, can realize the mode of this purpose the most a kind of be through being incubated processing for reduction furnace inside, the thermal field and the furnace wall of reduction furnace inside isolated.
In conjunction with above-mentioned thought; The utility model embodiment discloses a kind of polycrystalline silicon reducing furnace; This polycrystalline silicon reducing furnace comprises stove tube and chassis; Said chassis is provided with many counter electrode, also comprises: be arranged at the stove tube inwall of said polycrystalline silicon reducing furnace and the thermal insulation layer between the outermost layer electrode on the said chassis.
Polycrystalline silicon reducing furnace in the present embodiment is through being provided with thermal insulation layer between the outermost layer electrode on stove tube inwall and the said chassis; Stoped the thermal exchange of reduction furnace inside to a certain extent with twere; Make the water jacket structure carry out refrigerative simultaneously to the stove tube, do not have influence on the inner thermal field of reduction furnace, promptly the temperature owing to the thermal insulation layer inwall can not reduce because of the cooling of stove tube; Thereby the transfer of heat does not take place in the reduction furnace inside that makes the insulation layer coat; Thereby guaranteed that the inner thermal field of reduction furnace is balanced, improved the quality of polysilicon product, made the thickness of the polycrystalline silicon rod of producing more even.And, because the setting of thermal insulation layer has reduced the loss of reduction furnace internal heat, guaranteed that the heat in the reduction furnace does not leak, reduced the loss of reduction furnace energy to a certain extent.
It more than is the core concept of the utility model; A lot of details have been set forth in the following description so that make much of the utility model; But the utility model can also adopt other to be different from alternate manner described here and implement; Those skilled in the art can do similar popularization under the situation of the utility model intension, so the utility model does not receive the restriction of following disclosed specific embodiment.
Secondly, the utility model combines synoptic diagram to be described in detail, when the utility model embodiment is detailed; For ease of explanation; The sectional view of expression device architecture can be disobeyed general ratio and done local the amplification, and said synoptic diagram is example, and it should not limit the scope of the utility model protection at this.The three-dimensional space size that in actual fabrication, should comprise in addition, length, width and the degree of depth.
Embodiment one
As shown in Figure 2; The disclosed polycrystalline silicon reducing furnace of present embodiment comprises stove tube and chassis 13, and said chassis 13 is provided with many counter electrode, and; This polycrystalline silicon reducing furnace also comprises; Be arranged at the stove tube inwall 5 of said polycrystalline silicon reducing furnace and the thermal insulation layer 2 between the outermost layer electrode on the said chassis, said thermal insulation layer 2 is the drum of up and down break-through, can be in the gas flow and the reaction process that do not influence in the reduction furnace.
Certainly, the air outlet can sealed or leave in the upper end of thermal insulation layer 2 also, so that better insulation and gas flow in the production process, in the present embodiment this do not done concrete restriction.
In addition, this polycrystalline silicon reducing furnace also comprises:
Be positioned at the entrance of cooling water 1 of stove tube below, furnace tube outer wall 3, the stove collet chuck mantle cavity 4 between stove tube inwall 5 and furnace tube outer wall 3; Be positioned at the cooling water outlet 6 on stove tube top; Run through the visor 7 of stove tube inwall 5 and furnace tube outer wall 3, be positioned at the electrode chuck 11 on the chassis 13, be arranged at the electrode on the electrode chuck 11; Be positioned at mixed gas inlet nozzle 9 and tail gas venting port 10 on the chassis 13, and the bearing 8 that links to each other with chassis 13.
Wherein, The B-B structure iron on said chassis 13 is as shown in Figure 3, and mixed gas inlet nozzle 9 is evenly distributed on the chassis 13, and tail gas venting port 10 is arranged at the center on chassis 13; In the polysilicon production process; The silicon core links to each other with electrode 12, is arranged in the form of a ring in the reduction furnace, and equally distributed mixed gas inlet nozzle 9 can be under the situation of no external interference with the tail gas venting port 10 that is arranged at the center on chassis 13; Guarantee that the reduction furnace internal gas is evenly distributed, and can not distribute because of the thermal field that gas flow influences in the reduction furnace.
Need to prove; As shown in Figure 2; Said thermal insulation layer 2 is arranged on the said chassis 13, and is concrete, and thermal insulation layer 2 is that conduct is placed on separately on the chassis 13 with relatively independent parts of reduction furnace; Thermal insulation layer 2 is between outermost electrode and stove tube inwall, and promptly thermal insulation layer 2 and 5 of said stove tube inwalls have the slit.When each blow-on, after needing be installed to thermal insulation layer 2 on the chassis 13 earlier, the stove tube is installed again, after each blowing out, also need earlier dismounting stove tube remove thermal insulation layer 2 again.
In addition, need to prove, in order to adapt to the Working environment of polycrystalline silicon reducing furnace; The material of thermal insulation layer answers resistance toheat good in the present embodiment; Adapting to the high temperature about 1100 ℃ in the polysilicon production process, and said thermal insulation layer needs stable chemical performance at high temperature; To avoid in use Yin Gaowen and discharge other material; And having influence on the purity of polysilicon product in the reduction furnace, said thermal insulation layer also should have good toughness, in order to avoid in use broken easily or smash.
Based on above requirement; Preferably; Said thermal insulation layer is processed by C/C matrix material, graphite material, sapphire whisker, titanium alloy, stainless steel, stupalith, heat resistance material or special material; Said heat resistance material comprises high-strength high-modulus fibre, high heat resistance fiber, new cellulose fiber, biological fiber, coating titanium white, high density composite etc., and said special material comprises sintering metal, Incoloy series material etc., and the Incoloy series material is commonly referred to as the nickel-base alloy steel; The Incoloy series material has resistance to high temperature oxidation and high temperature resistance carburizing; The muriatic stress corrosion crack of ability promptly has good anti-uniform corrosion performance, anti-high radiation, anti-oxidant and outstanding welding property etc.The Incoloy series material has multiple model, like INCOLOY800/800H/800HT/840/825 etc.; Said C/C matrix material is a kind of pure charcoal heterogeneous structure that matrix is formed for being wild phase with charcoal fiber or its fabric with the pyrolytic carbon of chemical vapor infiltration or resin charcoal, the asphalt carbon of liquid impregnation-charing.
Present embodiment is through being provided with the mode of thermal insulation layer in reduction furnace; Stoped the thermal exchange of reduction furnace inside to a certain extent with twere; And then can effectively prevent the calorific loss in the reduction furnace; The assurance thermal field is balanced, has improved the even thickness degree of silicon rod, has also reduced the unit consumption of energy of production of polysilicon to a great extent.
Embodiment two
The structure iron of the disclosed polycrystalline silicon reducing furnace of present embodiment is as shown in Figure 4; The structure of the identical expression of drawing label is also identical, and different with a last embodiment is that the said thermal insulation layer 2 in the present embodiment is fixed on the said stove tube inwall 5; Be that thermal insulation layer 2 and 5 of stove tube inwalls do not have the slit; In the stove tube course of processing, can directly thermal insulation layer 2 be fixed on the stove tube, together dismantle with the stove tube during each start-stop stove.
The above only is the preferred embodiment of the utility model, is not the utility model is done any pro forma restriction.
Though the utility model discloses as above with preferred embodiment, yet be not in order to limit the utility model.Any those of ordinary skill in the art; Do not breaking away under the utility model technical scheme scope situation; All the method for above-mentioned announcement capable of using and technology contents are made many possible changes and modification to the utility model technical scheme, or are revised as the equivalent embodiment of equivalent variations.Therefore, every content that does not break away from the utility model technical scheme, all still belongs in the scope of the utility model technical scheme protection any simple modification, equivalent variations and modification that above embodiment did according to the technical spirit of the utility model.
Claims (7)
1. a polycrystalline silicon reducing furnace comprises stove tube and chassis, and said chassis is provided with many counter electrode, it is characterized in that, also comprises: be arranged at the stove tube inwall of said polycrystalline silicon reducing furnace and the thermal insulation layer between the outermost layer electrode on the said chassis.
2. polycrystalline silicon reducing furnace according to claim 1 is characterized in that, said thermal insulation layer is the drum of up and down break-through.
3. polycrystalline silicon reducing furnace according to claim 2 is characterized in that said thermal insulation layer is arranged on the said chassis.
4. polycrystalline silicon reducing furnace according to claim 3 is characterized in that, has the slit between said thermal insulation layer and said stove tube inwall.
5. polycrystalline silicon reducing furnace according to claim 2 is characterized in that, said thermal insulation layer is fixed in said stove tube inwall.
6. according to each described polycrystalline silicon reducing furnace of claim 1-5, it is characterized in that said thermal insulation layer is processed by one of C/C matrix material, graphite material, sapphire whisker, titanium alloy, stainless steel, stupalith, Incoloy series material.
7. polycrystalline silicon reducing furnace according to claim 1 is characterized in that, said chassis is provided with equally distributed mixed gas inlet nozzle, and said center chassis is provided with the tail gas venting port.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201120164131 CN202170244U (en) | 2011-05-20 | 2011-05-20 | Polycrystalline silicon reducing furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201120164131 CN202170244U (en) | 2011-05-20 | 2011-05-20 | Polycrystalline silicon reducing furnace |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202170244U true CN202170244U (en) | 2012-03-21 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 201120164131 Expired - Fee Related CN202170244U (en) | 2011-05-20 | 2011-05-20 | Polycrystalline silicon reducing furnace |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102730692A (en) * | 2012-05-09 | 2012-10-17 | 天津大学 | Energy-saving polysilicon reduction furnace chassis and implementation method thereof |
| CN102923708A (en) * | 2012-11-04 | 2013-02-13 | 张海峰 | Reducing furnace 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 |
| CN108675304A (en) * | 2018-08-31 | 2018-10-19 | 四川永祥新能源有限公司 | A kind of polycrystalline silicon reducing furnace |
-
2011
- 2011-05-20 CN CN 201120164131 patent/CN202170244U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102730692A (en) * | 2012-05-09 | 2012-10-17 | 天津大学 | Energy-saving polysilicon reduction furnace chassis and implementation method thereof |
| CN102923708A (en) * | 2012-11-04 | 2013-02-13 | 张海峰 | Reducing furnace 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 |
| CN108675304A (en) * | 2018-08-31 | 2018-10-19 | 四川永祥新能源有限公司 | A kind of polycrystalline silicon reducing furnace |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120321 Termination date: 20190520 |