CN106587071A - Equipment and method for improving purification yield of polycrystalline silicon through transversely solidifying and overlapping electric field - Google Patents
Equipment and method for improving purification yield of polycrystalline silicon through transversely solidifying and overlapping electric field Download PDFInfo
- Publication number
- CN106587071A CN106587071A CN201611258337.8A CN201611258337A CN106587071A CN 106587071 A CN106587071 A CN 106587071A CN 201611258337 A CN201611258337 A CN 201611258337A CN 106587071 A CN106587071 A CN 106587071A
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- Prior art keywords
- graphite
- graphite crucible
- annular
- water
- electric field
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 229910021420 polycrystalline silicon Inorganic materials 0.000 title claims abstract description 26
- 230000005684 electric field Effects 0.000 title claims abstract description 20
- 238000000034 method Methods 0.000 title claims description 12
- 238000000746 purification Methods 0.000 title abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 78
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 78
- 239000010439 graphite Substances 0.000 claims abstract description 78
- 238000007711 solidification Methods 0.000 claims abstract description 19
- 230000008023 solidification Effects 0.000 claims abstract description 19
- 238000010438 heat treatment Methods 0.000 claims abstract description 12
- 238000001816 cooling Methods 0.000 claims abstract description 8
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 15
- 229910052710 silicon Inorganic materials 0.000 claims description 15
- 239000010703 silicon Substances 0.000 claims description 15
- 229920005591 polysilicon Polymers 0.000 claims description 11
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 6
- 239000011248 coating agent Substances 0.000 claims description 6
- 238000000576 coating method Methods 0.000 claims description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 5
- 229910052802 copper Inorganic materials 0.000 claims description 5
- 239000010949 copper Substances 0.000 claims description 5
- 239000002210 silicon-based material Substances 0.000 claims description 4
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 3
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 229910052786 argon Inorganic materials 0.000 claims description 3
- 239000000498 cooling water Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 3
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- 239000004575 stone Substances 0.000 claims 1
- 239000007788 liquid Substances 0.000 abstract description 6
- 238000009792 diffusion process Methods 0.000 abstract description 3
- 230000000694 effects Effects 0.000 abstract description 3
- 239000012535 impurity Substances 0.000 description 10
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 229910052571 earthenware Inorganic materials 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000005204 segregation Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 238000003723 Smelting Methods 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002271 resection Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/037—Purification
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Silicon Compounds (AREA)
Abstract
The invention discloses equipment for improving a purification yield of polycrystalline silicon through transversely solidifying and overlapping an electric field. The equipment is characterized by comprising a water-cooling column, wherein a graphite sleeve is arranged at the outer side of a side wall of the water-cooling column; a graphite crucible is arranged at the outer side of the side wall of the graphite sleeve; axes of the water-cooling column, the graphite sleeve and the graphite crucible are located on the same straight line; an annular heating element is arranged at the outer side of the side wall of the graphite crucible; an annular heating body is arranged at the outer side of the side wall of the annular heating element; a rotary tray is arranged at the bottom of the graphite crucible; a circulating flow channel is arranged in the water-cooling column; and the graphite sleeve and the graphite crucible are connected with positive and negative electrodes of a power supply respectively. According to the equipment disclosed by the invention, the manner of transversely solidifying and overlapping the electric field is adopted, the thickness of a diffusion layer of a solid-liquid interface is reduced through adopting a centrifugal force and an electric field force and a fractional solidification effect is increased.
Description
Technical field
The present invention relates to a kind of lateral solidification superposition of electric field improves the apparatus and method of polycrystalline silicon purifying yield.
Background technology
Directional solidification purification is the major technique for removing metal impurities in polysilicon, is widely used in polycrystalline silicon ingot casting, smelting
In golden method purification process.
What directional solidification purification was utilized is fractional condensation behavior of the impurity at solid liquid interface：In directional solidification process, due to miscellaneous
Different solubility of the prime element in solid phase and liquid phase, solute can redistribute behavior at the solid liquid interface, redistribute
Degree together decided on by segregation coefficient and freezing rate.Segregation coefficient k0 of the metal impurities in silicon<<1, can be constantly to liquid
It is enriched with state silicon, the region impurity content of initial solidification is low, final set region impurity content highest.Directional solidification can make work
Metals content impurity in industry silicon reduces more than two orders of magnitude, in commercial production further reaches the Partial Resection of final set
The purpose of purification.
But traditional directional solidification technique is solidified from bottom to top, and the clearance of impurity is relatively low, final set
Easily there is Inversion in extrinsic region, reduce the yield of product.
The content of the invention
According to technical problem set forth above, and a kind of lateral solidification superposition of electric field is provided and improves polycrystalline silicon purifying yield
Apparatus and method.The technological means that the present invention is adopted are as follows：
A kind of lateral solidification superposition of electric field improves the equipment of polycrystalline silicon purifying yield, it is characterised in that including water-cooled column, institute
The side-wall outer side for stating water-cooled column is provided with graphite sleeve, and the side-wall outer side of the graphite sleeve is provided with graphite crucible, the water-cooled column,
The axis of the graphite sleeve and the graphite crucible is located along the same line, and the side-wall outer side of the graphite crucible is provided with annular
Heater, the side-wall outer side of the annular heater are provided with annular-heating body, and the bottom of the graphite crucible is provided with rotary-tray,
Circulatory flow is provided with the water-cooled column, the graphite sleeve and the graphite crucible are connected with power positive cathode respectively.
The graphite sleeve is connected with the rotary-tray.The rotary-tray can make the graphite crucible and the graphite
Sleeve is rotated by axle of its axis respectively.
The graphite sleeve is used to prevent silicon material splashing from damaging the water-cooled column.
The material of the water-cooled column is rustless steel or copper.
The annular heater is ring-shaped graphite heater.
The annular-heating body is toroidal inductor or ring-shaped graphite electrode.
The inwall of the graphite crucible scribbles coating, and the coating is carborundum or silicon nitride layer, the graphite crucible
The demoulding is toppled over after facilitating polycrystalline silicon ingot casting solidification in isosceles trapezoid shape in longitudinal section.
The invention also discloses a kind of use the said equipment lateral solidification superposition of electric field improves the side of polycrystalline silicon purifying yield
Method, it is characterised in that with following steps：
S1, silicon material is placed in the graphite crucible, reaction compartment is evacuated to into 0.1-3Pa backlash and enters the argon that flows
Gas, makes pressure in reaction compartment be 60000-100000Pa, and the annular-heating body will be described with the programming rate of 10 DEG C/min
Annular heater is heated to 1550 DEG C, is incubated 0.5-1h, obtains the silicon melt being completely melt；
Cooling water is poured in S2, the circulatory flow, opening the power supply makes the graphite sleeve with the graphite crucible
Between form electric field, after polysilicon starts in the outer wall forming core of the graphite sleeve, the graphite sleeve and the graphite earthenware
Crucible is rotated with the speed of 1-300r/min with the rotary-tray, meanwhile, the annular heater is with the cooling speed of 1-10 DEG C/h
Degree, makes the stable thermograde that is internally formed in the graphite crucible, promotes polysilicon along radial direction with 0.7mm-
The speed of 2mm/min is grown；
S3, when 80% silicon melt is frozen into polysilicon, the rotary speed of the rotary-tray lifts 10-50%, together
When, increase the electric current of the power supply, improve the fractional condensation of impurity；
S4, when 90% silicon melt is frozen into polysilicon, close the power supply, take out the water-cooled column and the graphite
Sleeve pipe.
The electric current of power supply described in step S2 is 1A-50A.
The enrichment that the power positive cathode realizes different impurities can be exchanged, for example, institute can be added on the graphite bush
State power supply positive electricity, on the graphite crucible plus the power supply negative electricity, as the electronegativity of ferrum, copper is higher than silicon, in electric field force and
Under the collective effect of centrifugal force, the element such as ferrum, copper can flow to the graphite crucible side-walls, can so realize ferrum, cupra
The enrichment of matter；For the electronegativity such as titanium, aluminum, magnesium are less than the metal of silicon, the power positive cathode position can be exchanged, it is right to realize
The enrichment of the metals such as titanium, aluminum, magnesium.
The present invention uses the mode of lateral solidification superposition of electric field, and using centrifugal force and electric field force reducing solid-liquid
Interface diffusion layer thickness, increases its fractional condensation effect.
The present invention has advantages below：
1. polycrystal silicon ingot utilization rate 5～10% is effectively improved；
2. high-purity region proportion is realized, actual yield 5～15% is improve.
3rd, solid-liquid separation is easily realized, prevents the back-diffusion of impurity.
The present invention can be widely popularized in fields such as polycrystalline silicon purifyings for the foregoing reasons.
Description of the drawings
The present invention is further detailed explanation with reference to the accompanying drawings and detailed description.
Fig. 1 be the present invention specific embodiment in a kind of lateral solidification superposition of electric field improve setting for polycrystalline silicon purifying yield
Standby structural representation.
Specific embodiment
Embodiment 1
As shown in figure 1, a kind of lateral solidification superposition of electric field improves the equipment of polycrystalline silicon purifying yield, including water-cooled column 1, institute
The side-wall outer side for stating water-cooled column 1 is provided with graphite sleeve 2, and the side-wall outer side of the graphite sleeve 2 is provided with graphite crucible 3, the water
The axis of cold post 1, the graphite sleeve 2 and the graphite crucible 3 is located along the same line, outside the side wall of the graphite crucible 3
Side is provided with annular heater 4, and the side-wall outer side of the annular heater 4 is provided with annular-heating body 5, the bottom of the graphite crucible 3
Portion is provided with rotary-tray 6, is provided with circulatory flow 7 in the water-cooled column 1, the graphite sleeve 2 and the graphite crucible 3 respectively with
8 both positive and negative polarity of power supply connects.
The graphite sleeve 2 is connected with the rotary-tray 6.
The material of the water-cooled column 1 is rustless steel or copper.
The annular heater 4 is ring-shaped graphite heater.
The annular-heating body 5 is toroidal inductor or ring-shaped graphite electrode.
The inwall of the graphite crucible 3 scribbles coating, and the coating is carborundum or silicon nitride layer, the graphite crucible 3
Longitudinal section in isosceles trapezoid shape.
Embodiment 2
The method that equipment lateral solidification superposition of electric field described in a kind of use embodiment 1 improves polycrystalline silicon purifying yield, tool
Have the following steps：
S1, silicon material is placed in the graphite crucible 3, reaction compartment is evacuated to into 0.1-3Pa backlash and enters the argon that flows
Gas, makes pressure in reaction compartment be 60000-100000Pa, and the annular-heating body 5 will be described with the programming rate of 10 DEG C/min
Annular heater 4 is heated to 1550 DEG C, is incubated 0.5-1h, obtains the silicon melt 9 being completely melt；
Cooling water is poured in S2, the circulatory flow 7, opening the power supply 8 makes the graphite sleeve 2 with the graphite earthenware
Electric field is formed between crucible 3, after polysilicon 10 starts in the outer wall forming core of the graphite sleeve 2, the graphite sleeve 2 and described
Graphite crucible 3 is rotated with the speed of 1-300r/min with the rotary-tray 6, meanwhile, the annular heater 4 is with 1-10 DEG C/h
Cooling rate cooling；
S3, when 80% silicon melt 9 is frozen into polysilicon 10, the rotary speed of the rotary-tray 6 lifts 10-
50%, meanwhile, increase the electric current of the power supply 8；
S4, when 90% silicon melt 9 is frozen into polysilicon 10, close the power supply 8, take out the water-cooled column 1 and institute
State graphite bush 2.
The electric current of power supply 8 described in step S2 is 1A-50A.
The above, the only present invention preferably specific embodiment, but protection scope of the present invention is not limited thereto,
Any those familiar with the art the invention discloses technical scope in, technology according to the present invention scheme and its
Inventive concept equivalent or change in addition, should all be included within the scope of the present invention.
Claims (8)
1. a kind of lateral solidification superposition of electric field improves the equipment of polycrystalline silicon purifying yield, it is characterised in that including water-cooled column, described
The side-wall outer side of water-cooled column is provided with graphite sleeve, and the side-wall outer side of the graphite sleeve is provided with graphite crucible, the water-cooled column, institute
The axis for stating graphite sleeve and the graphite crucible is located along the same line, and the side-wall outer side of the graphite crucible is provided with annular and sends out
Hot body, the side-wall outer side of the annular heater are provided with annular-heating body, and the bottom of the graphite crucible is provided with rotary-tray, institute
State, the graphite sleeve and the graphite crucible are connected with power positive cathode respectively.
2. equipment according to claim 1, it is characterised in that：The graphite sleeve is connected with the rotary-tray.
3. equipment according to claim 1, it is characterised in that：The material of the water-cooled column is rustless steel or copper.
4. equipment according to claim 1, it is characterised in that：The annular heater is ring-shaped graphite heater.
5. equipment according to claim 1, it is characterised in that：The annular-heating body is toroidal inductor or annular stone
Electrode ink.
6. the equipment according to claim 1-5 any claim, it is characterised in that：The inwall of the graphite crucible is scribbled
Coating, the coating are carborundum or silicon nitride layer, and the longitudinal section of the graphite crucible is in isosceles trapezoid shape.
7. a kind of usage right requires the method that the equipment lateral solidification superposition of electric field described in 6 improves polycrystalline silicon purifying yield, its
It is characterized by following steps：
S1, silicon material is placed in the graphite crucible, reaction compartment is evacuated to into 0.1-3Pa backlash and enters the argon that flows, made
In reaction compartment, pressure is 60000-100000Pa, and the annular-heating body is with the programming rate of 10 DEG C/min by described annular
Hot body is heated to 1550 DEG C, is incubated 0.5-1h, obtains the silicon melt being completely melt；
Cooling water is poured in S2, the circulatory flow, opening the power supply makes between the graphite sleeve and the graphite crucible
Form electric field, after polysilicon starts in the outer wall forming core of the graphite sleeve, the graphite sleeve and the graphite crucible with
The rotary-tray is rotated with the speed of 1-300r/min, meanwhile, the annular heater is dropped with the cooling rate of 1-10 DEG C/h
Temperature；
S3, when 80% silicon melt is frozen into polysilicon, the rotary speed of the rotary-tray lifts 10-50%, meanwhile, increase
Plus the electric current of the power supply；
S4, when 90% silicon melt is frozen into polysilicon, close the power supply, take out the water-cooled column and the graphite cannula
Pipe.
8. method according to claim 1, it is characterised in that：The electric current of power supply described in step S2 is 1A-50A.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611258337.8A CN106587071B (en) | 2016-12-30 | 2016-12-30 | A kind of lateral solidification superposition of electric field improves the device and method of polycrystalline silicon purifying yield |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611258337.8A CN106587071B (en) | 2016-12-30 | 2016-12-30 | A kind of lateral solidification superposition of electric field improves the device and method of polycrystalline silicon purifying yield |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106587071A true CN106587071A (en) | 2017-04-26 |
| CN106587071B CN106587071B (en) | 2018-09-04 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611258337.8A Expired - Fee Related CN106587071B (en) | 2016-12-30 | 2016-12-30 | A kind of lateral solidification superposition of electric field improves the device and method of polycrystalline silicon purifying yield |
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| CN (1) | CN106587071B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114086240A (en) * | 2021-11-09 | 2022-02-25 | 北京华卓精科科技股份有限公司 | Annular crucible, and crystal transverse directional growth device and method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62501067A (en) * | 1984-11-05 | 1987-04-30 | 三菱マテリアル株式会社 | Quality improvement method for vitreous silica containers |
| CN202529852U (en) * | 2011-12-08 | 2012-11-14 | 王洪举 | Polycrystalline silicon centrifuging purifying furnace |
| US8409319B2 (en) * | 2008-08-12 | 2013-04-02 | Ulvac, Inc. | Silicon purification method |
| CN104131342A (en) * | 2014-07-17 | 2014-11-05 | 大连理工大学 | Electromagnetic disturbance polysilicon impurity-removing device and method |
| CN105819451A (en) * | 2016-03-08 | 2016-08-03 | 大连理工大学 | Technology for inducing alloy directional solidification growth and reinforcing alloy refining process by direct current electric field |
-
2016
- 2016-12-30 CN CN201611258337.8A patent/CN106587071B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62501067A (en) * | 1984-11-05 | 1987-04-30 | 三菱マテリアル株式会社 | Quality improvement method for vitreous silica containers |
| US8409319B2 (en) * | 2008-08-12 | 2013-04-02 | Ulvac, Inc. | Silicon purification method |
| CN202529852U (en) * | 2011-12-08 | 2012-11-14 | 王洪举 | Polycrystalline silicon centrifuging purifying furnace |
| CN104131342A (en) * | 2014-07-17 | 2014-11-05 | 大连理工大学 | Electromagnetic disturbance polysilicon impurity-removing device and method |
| CN105819451A (en) * | 2016-03-08 | 2016-08-03 | 大连理工大学 | Technology for inducing alloy directional solidification growth and reinforcing alloy refining process by direct current electric field |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114086240A (en) * | 2021-11-09 | 2022-02-25 | 北京华卓精科科技股份有限公司 | Annular crucible, and crystal transverse directional growth device and method |
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| CN106587071B (en) | 2018-09-04 |
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