CN114752994A - Method and device for reducing crystal hidden crack of straightened silicon core rod - Google Patents
Method and device for reducing crystal hidden crack of straightened silicon core rod Download PDFInfo
- Publication number
- CN114752994A CN114752994A CN202210246654.7A CN202210246654A CN114752994A CN 114752994 A CN114752994 A CN 114752994A CN 202210246654 A CN202210246654 A CN 202210246654A CN 114752994 A CN114752994 A CN 114752994A
- Authority
- CN
- China
- Prior art keywords
- crystal
- core rod
- silicon core
- single crystal
- furnace equipment
- 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.)
- Pending
Links
- 239000013078 crystal Substances 0.000 title claims abstract description 266
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 title claims abstract description 130
- 238000000034 method Methods 0.000 title claims abstract description 60
- 230000012010 growth Effects 0.000 claims abstract description 27
- 239000000498 cooling water Substances 0.000 claims abstract description 20
- 230000008569 process Effects 0.000 claims abstract description 19
- 239000007788 liquid Substances 0.000 claims abstract description 17
- 238000004321 preservation Methods 0.000 claims description 20
- 238000002360 preparation method Methods 0.000 claims description 17
- 229910052710 silicon Inorganic materials 0.000 claims description 17
- 239000010703 silicon Substances 0.000 claims description 17
- 238000010438 heat treatment Methods 0.000 claims description 13
- 238000001816 cooling Methods 0.000 claims description 8
- 238000007599 discharging Methods 0.000 claims description 8
- 238000000137 annealing Methods 0.000 claims description 6
- 238000013459 approach Methods 0.000 claims description 4
- 238000007664 blowing Methods 0.000 claims description 3
- 230000007547 defect Effects 0.000 abstract 1
- 238000010899 nucleation Methods 0.000 description 12
- 239000011810 insulating material Substances 0.000 description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 229910002804 graphite Inorganic materials 0.000 description 6
- 239000010439 graphite Substances 0.000 description 6
- 239000012774 insulation material Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 229920005591 polysilicon Polymers 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000007600 charging Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000009599 head growth Effects 0.000 description 1
- 238000000462 isostatic pressing Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/20—Controlling or regulating
- C30B15/206—Controlling or regulating the thermal history of growing the ingot
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/14—Heating of the melt or the crystallised materials
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/20—Controlling or regulating
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/20—Controlling or regulating
- C30B15/203—Controlling or regulating the relationship of pull rate (v) to axial thermal gradient (G)
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B28/00—Production of homogeneous polycrystalline material with defined structure
- C30B28/04—Production of homogeneous polycrystalline material with defined structure from liquids
- C30B28/10—Production of homogeneous polycrystalline material with defined structure from liquids by pulling from a melt
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/02—Elements
- C30B29/06—Silicon
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
The invention provides a method and a device for reducing crystal subfissure of a straightened silicon core rod, which comprises the following steps: cooling water is introduced into single crystal furnace equipment for preparing silicon core rod crystals, so that the temperature of the single crystal furnace equipment is controlled within a preset range; a curing felt and a heat shield device are arranged at the upper part of a guide cylinder of the single crystal furnace equipment; starting the single crystal furnace equipment and entering a crystal growth stage; after the crystal growth stage is finished, separating the prepared silicon core rod crystal from the liquid level to a preset height, simultaneously reducing the power of the single crystal furnace equipment, and after the silicon core rod crystal is cooled for a preset time, closing the power; the silicon core rod crystal needs to be stood and discharged from the furnace within a preset time. By utilizing the method for reducing the subfissure of the straightened silicon core rod crystal and the device for executing the method, the defects of subfissure, cracks and the like of the silicon core rod crystal in the straightening process are effectively reduced, and the silicon core rod crystal is not only limited to a single crystal in the prefabricating process, so that the difficulty in preparing the silicon core rod crystal is reduced.
Description
Technical Field
The invention relates to the technical field of polycrystalline silicon, relates to a method for straightening silicon core rod crystals, and particularly relates to a method and a device for reducing subfissure of the straightened silicon core rod crystals.
Background
Silicon core is carrier for producing polysilicon by gas phase (CVD) deposition in reducing furnace, and the Czochralski method is one of the common methods for producing solar silicon core.
At present, most of domestic and foreign polysilicon factories continue to use a process method and a thermal field system for producing solar energy single crystals in the production of silicon core rod crystals, and the thermal field system is mainly characterized by large temperature gradient and high crystal growth speed.
In practical applications, the pulling of the silicon seed rod crystal is not limited to single crystal but may be polycrystalline, and if the crystal is polycrystalline, the anisotropy of the crystal is particularly prominent due to the difference of crystal orientation between the polycrystalline and the single crystal, and thus the problems such as hidden crack, brittle fracture and the like are more easily generated.
In addition, according to the characteristics of square silicon cores, the silicon core raw material rod needs to have the characteristics of no hidden crack, brittle fracture, uniform appearance, uniform length and the like.
The invention patent with application number CN201710250236.4, a device and a method for eliminating crystal subfissure of silicon core rods, which comprises the following steps:
1) a heat shield adjusting device is additionally arranged, the heat shield device is positioned above the molten silicon liquid level, the upper end of the heat shield device is arranged on a cover plate, the heat shield device is divided into a heat shield inner layer and a heat shield outer layer, a gap filled with a heat insulation material is reserved between the heat shield inner layer and the heat shield outer layer, the gap gradually widens from top to bottom, an included angle theta 2 of 4-7 degrees is formed between the heat shield inner layer and the heat shield outer layer, the included angle theta 3 between the heat shield inner layer and the silicon core rod crystal is 8-13 degrees, the included angle theta 1 between the heat shield outer layer and the silicon core rod crystal is 4-6 degrees, the distance between the lowest end of the heat shield inner layer and the molten silicon liquid level is 18-22mm, and the distance between the lowest end of the heat shield inner layer and the silicon core rod crystal is 58-63 mm; the inner layer and the outer layer of the heat shield are made of isotropic isostatic pressing graphite, the filled heat insulation material is graphite soft felt, the temperature gradient of a radial growth interface in the heat shield device is close to zero, and the central axial temperature gradient and the surface axial temperature gradient Gc/Ge of the crystal are 1.1: 1.3-1.4;
2) And (3) crystal growth stage: the growth rate is controlled to be 30-60mm/hr, the diameter of the crystal is controlled to be 147-157mm, and the time of the crystal at 800-1000 ℃ is controlled to be 80-180 min;
3) and (3) annealing: taking the power before ending as a reference, cooling step by step, sequentially reducing the power to 1/2 and 1/3, and finally reducing the power to 0;
4) stopping the furnace and cooling, keeping the crystal in the furnace for at least 10 hours, and discharging the crystal;
through the operation, the subfissure of the silicon core rod crystal is eliminated.
In addition, in a further scheme, the central axial temperature gradient Gc of the crystal is 2-3 ℃/mm.
In addition, in the step 2), the head growth rate is controlled to be 50-60mm/hr, the single crystal structure is kept within 200mm of the crystal bar growth, and the tail growth rate is 30-35 mm/hr.
In addition, in the further scheme, in the step 3), when the temperature is reduced step by step, the next step is carried out at an interval of 5min after each step is finished, and the whole annealing stage is finished within 30 min.
Although the patent discloses a device and a method for eliminating the silicon core rod crystal subfissure, the preparation of the silicon core rod crystal with large diameter is not mentioned, and the subfissure property of the silicon core rod crystal is continuously lengthened along with the increase of the preparation diameter, so that the problems of the silicon core rod crystal such as subfissure, crack and the like are more prominent.
Disclosure of Invention
In view of the above problems, the present invention provides a method and an apparatus for reducing subfissure of crystal of a straightened silicon core rod, which can reduce subfissure and crack of crystal of silicon core rod by reducing longitudinal temperature difference of thermal field system, reducing temperature gradient and optimizing treatment process.
According to one aspect of the invention, a method for reducing crystal subfissure of a Czochralski silicon seed rod is provided, which comprises the following steps:
s110, preparation stage: introducing cooling water into single crystal furnace equipment for preparing silicon core rod crystals, and controlling the temperature of the cooling water in the single crystal furnace equipment within a preset range;
s120, adding a curing felt and a heat shield device: annularly arranging a curing felt on the upper part of a guide cylinder of the single crystal furnace equipment, and installing a heat shield device which is adjusted according to preset data; wherein,
the solidification felt and the heat shield device enable the single crystal furnace equipment to meet the condition that the temperature gradient of a radial growth interface of the crystal approaches to zero, so that the longitudinal temperature gradient is reduced;
s130, crystal growth stage: after the curing felt and the heat shield device are adjusted, starting single crystal furnace equipment to enable liquid in the single crystal furnace to enter a crystal growth stage;
s140, annealing: after the crystal growth stage is finished, separating the prepared silicon core rod crystal from the liquid level to a preset height, simultaneously reducing the power of the single crystal furnace equipment, and after the silicon core rod crystal is cooled for a preset time, closing the power of the single crystal furnace equipment;
S150, blowing out and cooling, standing and discharging: and after the single crystal furnace equipment is closed, standing the silicon core rod crystals for a preset time, and discharging the silicon core rod crystals out of the furnace.
According to another aspect of the invention, the device for reducing the subfissure of the czochralski silicon core rod crystal is used for executing the method for reducing the subfissure of the czochralski silicon core rod crystal, and comprises a single crystal furnace device, and is characterized by further comprising a thermal field device, a preset system and an auxiliary system; wherein,
the thermal field device is used for heating and preserving heat of the single crystal furnace equipment;
the presetting system is used for presetting data parameters required by the single crystal furnace equipment in the process of preparing the silicon core rod crystal;
the auxiliary system is used for providing auxiliary devices required by the single crystal furnace equipment in the silicon core rod crystal preparation process.
In addition, the preferable structure is that the thermal field device comprises a heating system and a heat preservation system; wherein, the heating system comprises a heater used for heating the silicon core rod crystal preparation liquid; the heat preservation system comprises an upper heat preservation cover, a middle heat preservation cover and a lower heat preservation cover and is used for heat preservation treatment of the preparation environment of the silicon core rod crystals.
Further, it is preferable that the preset system includes a program preset unit of the single crystal furnace apparatus, a control process preset unit of the single crystal furnace apparatus, and a temperature control unit of the single crystal furnace apparatus.
By utilizing the method and the device for reducing the subfissure of the straightened silicon core rod crystal, the probability of subfissure in the drawing process of the silicon core rod crystal is reduced by reasonably adjusting the longitudinal temperature difference and the temperature gradient, the drawing process of the silicon core rod crystal is optimized by an auxiliary system, the straightening of the silicon core rod crystal is not limited to single crystal, but also can be polycrystalline, the production difficulty is reduced, and the production efficiency is improved.
Drawings
Other objects and results of the present invention will become more apparent and more readily appreciated as the same becomes better understood by reference to the following description and appended claims, taken in conjunction with the accompanying drawings. In the drawings:
FIG. 1 shows a flow diagram of a method of reducing subfissure of a straightened silicon seed rod crystal according to the present invention;
FIG. 2 shows a block diagram of a system for reducing subfissure of a crystal of a straightened silicon core rod according to the invention.
Description of the drawings:
1. curing the felt; 2. An upper heat-preserving barrel; 3. A thermal insulation material; 4. A draft tube;
5. a heater; 6. A graphite crucible; 7. A middle heat-insulating barrel; 8. A middle furnace barrel;
9. a lower heat-preserving barrel; 10. A water injection hole; 11. Silicon core rod crystals; 12. heat preservation cover
The same reference numbers in all figures indicate similar or corresponding features or functions.
Detailed Description
The following embodiments of the present invention are provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the features in the following embodiments and examples may be combined with each other without conflict.
It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.
Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
As shown in FIG. 1, a flow chart of a method for reducing subfissure of crystal of a straightened silicon seed rod according to the invention is shown, and comprises the following steps:
S110, preparation stage:
cooling water is introduced into the single crystal furnace equipment for preparing the silicon core rod crystal 11, and the cooling water flows through the wall of the whole single crystal furnace equipment through the cooling water injection holes 10 arranged on the outer wall of the single crystal furnace equipment, so that the temperature of the cooling water inside the single crystal furnace equipment is controlled within a preset range.
In detail, the preset range of the temperature of the internal cooling water of the single crystal furnace equipment is 28-36 ℃.
S120, adding a curing felt and a heat shield device:
the method is characterized in that a curing felt 1 is annularly arranged on the upper portion of a guide shell 4 in single crystal furnace equipment, and a heat shield device which is adjusted according to preset data is mounted on a heat insulation cover 12, in detail, the height of the curing felt 1 is flush with that of a middle furnace shell 8, and the single crystal furnace equipment meets the condition that the temperature gradient of a crystal radial growth interface approaches to zero through the curing felt 1, the curing felt 1 and the heat shield device which are annularly arranged on the upper portion of the guide shell 4, so that the longitudinal temperature gradient is reduced.
S130, crystal growth stage:
after the solidification felt 1 and the heat shield device are adjusted, starting single crystal furnace equipment to enable liquid in the single crystal furnace to enter a crystal growth stage, wherein in detail, the growth rate of the crystal is controlled to be 0.76-1.00 mm/min, and the diameter range of the crystal is 190-205 mm.
The method comprises the following steps of starting a seeding stage, wherein the seeding stage is a seeding stage before a crystal growth stage, the seeding stage comprises seed crystal-shouldering, in detail, after a chuck and the seed crystal are correctly installed, the seed crystal is in contact with a silicon core rod crystal preparation liquid phase, the state of neither growth nor insolubilization is kept for a long time, the seeding stage is started, the speed value of the seeding stage is 0.76mm/min, and the head length of the crystal is 600 mm.
In detail, the seed crystal in the seeding stage is a single crystal, the single crystal is arranged before the shouldering is carried out to a half, the polycrystal can be arranged from the shouldering rear half part to the shouldering, and the operation difficulty of the silicon core rod crystal is reduced by converting the single crystal into the polycrystal.
S140, annealing:
and after the crystal growth stage is finished, separating the silicon core rod crystal 11 prepared by crystal growth from the liquid level to a preset height, simultaneously reducing the power of the single crystal furnace equipment, and after the silicon core rod crystal 11 is cooled for a preset time, closing the power of the single crystal furnace equipment.
In detail, the range from the liquid level to the preset height is 50-200 mm, the power reduction is 10-30 kw, and the process of reducing the power is preferably performed in a segmented manner, and the preset cooling time is 30 min.
S150, blowing out and cooling, standing and discharging:
and (3) after the single crystal furnace equipment is closed, standing the silicon core rod crystal 11 for a preset time, and discharging.
In detail, the standing time is 8-8.1 h.
It should be noted that the specific values mentioned above are obtained experimentally and the results obtained may vary for any equipment and parameter change, and therefore the data are only for the present apparatus and method.
Compared with the prior art, the method for reducing the crystal subfissure of the straightened silicon core rod has at least the following advantages:
1. the invention relates to a method for reducing the subfissure of a crystal of a straightened silicon core rod, which reduces the temperature difference by annularly arranging a curing felt 1 on a guide cylinder 4, thereby reducing the longitudinal temperature gradient, leading the temperature gradient of the radial growth interface of the crystal to approach zero and realizing the reduction of the subfissure probability of the crystal of the silicon core rod.
2. The invention relates to a method for reducing the subfissure of a straightened silicon core rod crystal, which is characterized in that a single crystal is used as a seed crystal for seeding, and then the middle part of a shouldering part can be used for pulling a polycrystal, so that the pulling difficulty of the silicon core rod crystal is reduced.
In order to implement the method for reducing the crystal subfissure of the Czochralski silicon core rod, an apparatus for reducing the crystal subfissure of the Czochralski silicon core rod is provided.
As shown in fig. 2, the system structure for reducing the subfissure of the pulled-straight silicon core rod crystal according to the present invention includes a single crystal furnace device, and is characterized by further including a thermal field device, a preset system and an auxiliary system, wherein the single crystal furnace device is operated by the data of the preset system under the action of the thermal field device and the auxiliary device to produce the silicon core rod crystal 11.
Specifically, the thermal field device is used for heating and insulating single crystal furnace equipment, and comprises a heating system and an insulating system; wherein, the heating system comprises a heater 5, a graphite crucible 6 and the like and is used for heating the silicon core rod crystal preparation liquid; the heat preservation system comprises an upper heat preservation barrel, a middle heat preservation barrel 7, a lower heat preservation barrel 9, a graphite carbon felt, a heat preservation cover 12 and the like, and is used for heat preservation treatment of the preparation environment of the silicon core rod crystals.
Specifically, the preset system is used for presetting data parameters required by the single crystal furnace equipment in the process of preparing the silicon core rod crystal 11, and specifically, the preset system comprises a program preset unit of the single crystal furnace equipment, a control process preset unit of the single crystal furnace equipment and a temperature control unit of the single crystal furnace equipment; the program presetting unit comprises cooling preset time, standing preset time and the like, the control process presetting unit of the single crystal furnace equipment comprises the lifting and rotating of the crystal graphite crucible 6, the lifting and rotating of seed crystals and the like, and the temperature control unit of the single crystal furnace equipment comprises the temperature of a seeding stage, the temperature of a crystal growth stage and the like, and is mainly used for carrying out collective specification on parameters required in the control process of the single crystal furnace equipment.
Specifically, the auxiliary system is used for providing an auxiliary device required by the single crystal furnace equipment in the preparation process of the silicon core rod crystal 11, specifically, the auxiliary system comprises oxygen, cooling water, argon and the like, and through the auxiliary system, the preparation efficiency of the silicon core rod crystal is increased, and the probability of subfissure is reduced.
The improvement point and effect of the system for reducing the crystal crazing of a drawn silicon core rod according to the present invention will be described in detail below.
First, the heating system and the heat-retaining system in the prior art were originally designed for the purpose of maintaining a suitable temperature gradient in the single crystal furnace apparatus, and the above design facilitates rapid crystallization of the single crystal, i.e., increases in the longitudinal temperature gradient. However, when the silicon core rod crystal 11 is polycrystalline, the above design may result in the silicon core rod crystal 11 being subfissure and not being cut into silicon cores, therefore, the invention enlarges the lower opening of the guide cylinder 4 on the basis of the prior art, and adjusts the heat insulating material 3 arranged inside the guide cylinder 4 from one half (i.e. filled) to one layer, and the height of the heat insulating material 3 is 1/3-4/5 of the height of the guide cylinder 4, the heat insulating material 3 in the embodiment is soft felt, or other heat insulating material, and here is not limited, the above two operations are aimed at reducing the temperature gradient of the silicon core rod crystal and reducing the probability of subfissure of the silicon core rod crystal.
Secondly, a curing felt 11 is annularly arranged in the upper space of a guide cylinder 4 in single crystal furnace equipment in the prior art, the height of the curing felt 11 is flush with the upper edge of a middle furnace cylinder 8 in the single crystal furnace equipment, the heat preservation effect is improved by arranging the curing felt 1 on the guide cylinder 4, and meanwhile, the longitudinal temperature gradient of the silicon core rod crystal is reduced.
Thirdly, when the crystal is pulled in the operation of the single crystal furnace equipment, the pulling speed is reduced at the head (the length is 600mm), the acquisition value of the pulling speed at the time is 0.76mm/min, after the pulling is finished, the operation power of the single crystal furnace equipment is gradually reduced, the distance between the prepared silicon core rod crystal 11 and the preparation liquid level of the silicon core rod crystal is kept between 50 mm and 200mm, and in the actual operation, the common distance range is between 50 mm and 100 mm.
Fourthly, cooling water is led into the side wall of the single crystal furnace equipment, the temperature inside the single crystal furnace equipment is kept stable through the cooling water, the temperature of the cooling water keeps the temperature inside the single crystal furnace equipment to be indirectly stable in the actual production operation, and the temperature of the cooling water also has influence on the temperature gradient inside the single crystal furnace equipment, and the conclusion is drawn through experiments: the temperature of the cooling water is properly increased, the process redundancy is favorably improved, the temperature range of the cooling water in the prior art is 23-27 ℃, the temperature range of the cooling water is 28-36 ℃ through experiments, the efficiency is higher, in actual operation, the temperature range of the cooling water is controlled to be 30-33 ℃, and the temperature prepared at the moment is the optimal temperature.
Fifthly, when the silicon core rod crystal is prepared by the system for reducing the subfissure of the drawn silicon core rod crystal, the diameter of the drawn silicon core rod crystal 11 is 190-205mm, it should be noted that the practical maximum diameter is 205mm in operation due to the limitation of the single crystal furnace equipment, when the device is used in other equipment, the drawn diameter of the crystal may not be limited to 205mm, and the prepared diameter may be longer.
Sixth, compared with the prior art, the device for reducing the silicon core rod crystal subfissure increases the distance between the lower opening position of the guide cylinder 4 and the silicon core rod crystal 11 by 10-20mm compared with the distance in the prior art.
It should be specially noted that, after the six major points are improved, the pulling of the silicon core rod crystal 11 only needs to be seeded into a single crystal, the whole silicon core rod crystal 11 is not limited to a single crystal, the operation difficulty for preparing the silicon core rod crystal is reduced by the side surface, and the operation effectively reduces the problem of the subfissure rate of the silicon core rod crystal.
The method and apparatus for reducing the crystal crazing of a silicon seed rod according to the present invention will be described in more detail with reference to the following examples.
Firstly, the existing process and single crystal furnace equipment are improved, and the specific improvements are as follows:
(1) adjusting the heat insulating material 3 of the guide shell 4 in the single crystal furnace equipment from one layer to a half layer, wherein the filling height of the heat insulating material 3 is 3/4 of the height of the guide shell 4;
(2) the distance between the lower mouth of the guide shell 4 and the silicon core rod is increased by 10-20mm relative to the distance of crystal pulling;
(3) the upper part of an upper heat-insulating barrel 2 of the single crystal furnace equipment is annularly provided with a heat-insulating material 3, wherein the heat-insulating material 3 is a solidified felt 1 and is used for insulating silicon core rod crystals;
(4) adjusting the water inlet temperature of the cooling water in the side wall of the single crystal furnace equipment to 30-32 ℃ from the original 23-27 ℃;
(5) adjusting the pulling speed within 500mm of the head of the silicon core rod crystal from the original 1.1mm/min to 0.76mm/min, separating the tail part from the prepared liquid level of the silicon core rod crystal after being lifted off, keeping the distance between the liquid levels at 50mm, adjusting the power of single crystal furnace equipment to 30Kw, and keeping the power of 30Kw for 30 min;
(6) when the crystal is pulled, the seeding is ensured to be a single crystal, more than half of the seeding is the single crystal, and the others are not required to be the single crystal.
The modification point is removed, and the other operation is performed with reference to the normal single crystal pulling operation.
The operation steps are as follows: the method comprises the steps of furnace cleaning, charging, melting, seeding, isometric, ending, cooling and discharging.
Compared with the prior art, the device for reducing the crystal subfissure of the straightened silicon core rod has at least the following advantages:
1. the device for reducing the subfissure of the crystal of the straightened silicon core rod has lower requirement on crystal pulling to form a single crystal, is not limited to the situation that the crystal is 200mm in front of the crystal of the silicon core rod, has higher efficiency and is more widely applicable.
2. The device for reducing the subfissure of the straightened silicon core rod crystal is beneficial to controlling the subfissure of the silicon core rod crystal by increasing the distance between the lower opening of the guide cylinder and the silicon core rod crystal, simultaneously reduces the heat insulation material in the guide cylinder and increases the heat insulation material arranged at the upper part of the upper heat insulation barrel, and the combination of the two methods ensures that the subfissure control effect is better.
3. The device for reducing the hidden crack of the crystal of the straightened silicon core rod can ensure that the diameter of a new silicon rod drawn by the device can reach 205mm, the diameter is increased by 1/3 compared with the prior art, and the hidden crack is more difficult to control as the diameter of the crystal of the silicon core rod is thicker, so the device can overcome more difficulty.
4. The device for reducing the crystal subfissure of the straightened silicon core rod has the advantages that the requirement on the lowest drawing speed is relatively reduced, and the requirement is relatively reduced to 0.5mm/min (namely 30mm/h), the thickness of the crystal can reach 0.76mm/min (namely 46mm/h), the operation is simpler, and the manufacture is more convenient.
The advantages of the method and the device for reducing the crystal subfissure of the straightened silicon core rod are complementary, so that the advantages in the device are correspondingly described through the method, and the advantages in the method are also embodied through the device.
A method and apparatus for reducing subfissure of straightened silicon seed rod crystals in accordance with the present invention is described above by way of example with reference to fig. 1 and 2. However, it will be appreciated by those skilled in the art that various modifications can be made to the method and apparatus for reducing subfissure in straightened silicon seed rod crystals as set forth in the foregoing description without departing from the scope of the invention. Therefore, the scope of the present invention should be determined by the contents of the appended claims.
Claims (10)
1. A method for reducing crystal subfissure of a straightened silicon core rod comprises the following steps:
s110, preparation stage: introducing cooling water into single crystal furnace equipment for preparing silicon core rod crystals, and controlling the temperature of the cooling water in the single crystal furnace equipment within a preset range;
S120, adding a curing felt and a heat shield device: annularly arranging a curing felt on the upper part of a guide cylinder of the single crystal furnace equipment, and installing a heat shield device which is adjusted according to preset data; wherein,
the solidified felt and the heat shield device enable the single crystal furnace equipment to meet the condition that the temperature gradient of a crystal radial growth interface approaches zero, so that the longitudinal temperature gradient is reduced;
s130, crystal growth stage: after the curing felt and the heat shield device are adjusted, starting single crystal furnace equipment to enable liquid in the single crystal furnace to enter a crystal growth stage;
s140, annealing: after the crystal growth stage is finished, separating the prepared silicon core rod crystal from the liquid level to a preset height, simultaneously reducing the power of the single crystal furnace equipment, and after the silicon core rod crystal is cooled for a preset time, closing the power of the single crystal furnace equipment;
s150, blowing out and cooling, standing and discharging: and after the single crystal furnace equipment is closed, standing the silicon core rod crystals for a preset time, and discharging the silicon core rod crystals out of the furnace.
2. The method for reducing crystal crazing of a straightened silicon seed rod according to claim 1, wherein the height of the fixing felt is flush with the height of a middle furnace cylinder of the single crystal furnace equipment.
3. The method for reducing the crystal subfissure of the straightened silicon core rod as claimed in claim 1, wherein the growth rate range of the crystal is controlled to be 0.76-1mm/min, and the diameter range of the crystal is 190-205 mm.
4. The method of reducing subfissure in straightened silicon seed rod crystals as recited in claim 1, wherein the height between the silicon seed rod crystals and the liquid level during the annealing stage is in the range of 50-200 mm.
5. The method for reducing the crystal subfissure of the straightened silicon core rod as claimed in claim 1, wherein in the process of reducing the power of the single crystal furnace equipment, the power is reduced to 10-30 kw.
6. The method of reducing subfissure in pulling straight silicon boule crystals according to claim 5,
in the process of reducing the power of the single crystal furnace equipment, the power is reduced in a segmented mode.
7. The method of reducing crystal crazing in a straightened silicon seed rod of claim 1,
and the silicon core rod crystal is kept still in the single crystal furnace equipment for 8-8.1 h.
8. A device for reducing the subfissure of a crystal of a straightened silicon core rod, which utilizes the method for reducing the subfissure of the crystal of the straightened silicon core rod as claimed in any one of claims 1 to 7, comprises single crystal furnace equipment, and is characterized by also comprising a thermal field device, a preset system and an auxiliary system; wherein,
The thermal field device is used for heating and insulating the single crystal furnace equipment;
the presetting system is used for presetting data parameters required by the single crystal furnace equipment in the process of preparing the silicon core rod crystal;
the auxiliary system is used for providing auxiliary devices required by the single crystal furnace equipment in the silicon core rod crystal preparation process.
9. The apparatus for reducing crystal crazing in a straightened silicon seed rod of claim 8,
the thermal field device comprises a heating system and a heat preservation system; wherein,
the heating system comprises a heater for heating the silicon core rod crystal preparation liquid;
the heat preservation system comprises an upper heat preservation cover, a middle heat preservation cover and a lower heat preservation cover and is used for heat preservation treatment of the preparation environment of the silicon core rod crystals.
10. The apparatus for reducing crystal crazing in a straightened silicon seed rod of claim 8,
the preset system comprises a program preset unit of the single crystal furnace equipment, a control process preset unit of the single crystal furnace equipment and a temperature control unit of the single crystal furnace equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210246654.7A CN114752994A (en) | 2022-03-14 | 2022-03-14 | Method and device for reducing crystal hidden crack of straightened silicon core rod |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210246654.7A CN114752994A (en) | 2022-03-14 | 2022-03-14 | Method and device for reducing crystal hidden crack of straightened silicon core rod |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114752994A true CN114752994A (en) | 2022-07-15 |
Family
ID=82327883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210246654.7A Pending CN114752994A (en) | 2022-03-14 | 2022-03-14 | Method and device for reducing crystal hidden crack of straightened silicon core rod |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114752994A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202297853U (en) * | 2011-11-10 | 2012-07-04 | 常州华盛恒能光电有限公司 | Low-energy-consumption thermal field for drawing monocrystalline silicon |
| CN103882519A (en) * | 2014-04-04 | 2014-06-25 | 天津环煜电子材料科技有限公司 | Silicon tube and preparation method for silicon-tube solar cell-grade polycrystalline silicon rod |
| CN105154972A (en) * | 2015-08-25 | 2015-12-16 | 河南协鑫光伏科技有限公司 | Square silicon core production method |
| CN107130295A (en) * | 2017-04-17 | 2017-09-05 | 宜昌南玻硅材料有限公司 | A kind of elimination hidden device and method split of silicon plug |
| CN112746312A (en) * | 2021-02-03 | 2021-05-04 | 中国电子科技集团公司第十三研究所 | Growth method of low-stress crystal |
-
2022
- 2022-03-14 CN CN202210246654.7A patent/CN114752994A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202297853U (en) * | 2011-11-10 | 2012-07-04 | 常州华盛恒能光电有限公司 | Low-energy-consumption thermal field for drawing monocrystalline silicon |
| CN103882519A (en) * | 2014-04-04 | 2014-06-25 | 天津环煜电子材料科技有限公司 | Silicon tube and preparation method for silicon-tube solar cell-grade polycrystalline silicon rod |
| CN105154972A (en) * | 2015-08-25 | 2015-12-16 | 河南协鑫光伏科技有限公司 | Square silicon core production method |
| CN107130295A (en) * | 2017-04-17 | 2017-09-05 | 宜昌南玻硅材料有限公司 | A kind of elimination hidden device and method split of silicon plug |
| CN112746312A (en) * | 2021-02-03 | 2021-05-04 | 中国电子科技集团公司第十三研究所 | Growth method of low-stress crystal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101323978B (en) | Large size sapphire crystal preparing technology and growing apparatus thereof | |
| JP5719282B2 (en) | Method for producing polycrystalline silicon | |
| CN104372408B (en) | Large size gallium oxide single crystal Czochralski growing method under normal pressure | |
| CN105442037A (en) | High-speed single crystal growth device | |
| CN110983429A (en) | Single crystal furnace and monocrystalline silicon preparation method | |
| WO2016041242A1 (en) | Quartz crucible used for repeatedly pulling monocrystalline silicon for multiple times and manufacturing method therefor | |
| JPH1192272A (en) | Single crystal production apparatus and production of single crystal | |
| JP2017100945A (en) | Improvement of high-temperature process using helium under adjusted pressure | |
| JP6302192B2 (en) | Single crystal growth apparatus and method | |
| CN108277534A (en) | A kind of graphite resistance heating SiC crystal growth furnace | |
| CN108203844B (en) | Magnesium tantalate series crystal and its preparing process | |
| CN114232070A (en) | Double-cavity structure and method for growing gallium oxide crystal by Czochralski method | |
| KR101501036B1 (en) | Sapphire single crystal and process for manufacturing the same | |
| CN220224440U (en) | Graphite crucible structure for silicon carbide single crystal growth | |
| US9410266B2 (en) | Process for producing multicrystalline silicon ingots by the induction method, and apparatus for carrying out the same | |
| CN114752994A (en) | Method and device for reducing crystal hidden crack of straightened silicon core rod | |
| CN205295534U (en) | High -speed growth of single crystal device | |
| CN201942779U (en) | Heat shield device applied to single crystal furnace | |
| CN213652724U (en) | Thermal field structure of continuous crystal pulling single crystal furnace | |
| CN104178813A (en) | Kyropoulos-process sapphire single-crystal growth furnace thermal-insulation side screen | |
| CN114875480A (en) | Single crystal furnace, heating and heat-preserving system thereof and method for growing gallium oxide crystals | |
| CN114616361B (en) | Method for producing silicon single crystal | |
| CN103266346B (en) | The growth apparatus of a kind of crystal Pulling YVO4 crystal and growing method based on this growth apparatus | |
| CN211036174U (en) | Crystal growth device | |
| CN113862783A (en) | Monocrystalline silicon preparation method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |