CN106283183A - A kind of polycrystalline silicon casting ingot process based on boron nitride coating - Google Patents
A kind of polycrystalline silicon casting ingot process based on boron nitride coating Download PDFInfo
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- CN106283183A CN106283183A CN201610695849.4A CN201610695849A CN106283183A CN 106283183 A CN106283183 A CN 106283183A CN 201610695849 A CN201610695849 A CN 201610695849A CN 106283183 A CN106283183 A CN 106283183A
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- 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
- C30B28/06—Production of homogeneous polycrystalline material with defined structure from liquids by normal freezing or freezing under temperature gradient
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/006—Surface treatment of glass, not in the form of fibres or filaments, by coating with materials of composite character
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- 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
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- 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
- C30B33/00—After-treatment of single crystals or homogeneous polycrystalline material with defined structure
- C30B33/02—Heat treatment
Abstract
The invention discloses a kind of polycrystalline silicon casting ingot process based on boron nitride coating, including step: one, prepared by crucible bottom coating；Two, polycrystalline silicon ingot casting: 201, charging；202, preheating；203, fusing；204, long crystalline substance；205, anneal and cool down: 2051, annealing for the first time: the heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T4 and is incubated 2h～3h, T4=1250 DEG C～1280 DEG C；2052, second time annealing: the heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T5 by T4 and is incubated 2h～3h；T5=900 DEG C～950 DEG C；2053, cooling.Step of the present invention is simple, reasonable in design and realization is easy, using effect is good, by coating one layer of base coat with boron nitride as primary raw material in crucible bottom, can effectively reduce crucible bottom oxygen content, and can effectively reduce the Hard Inclusion of ingot casting finished product, annealing process is adjusted simultaneously, the quality of ingot casting finished product can be improved.
Description
Technical field
The invention belongs to polycrystalline silicon ingot casting technical field, especially relate to a kind of polycrystalline silicon ingot casting based on boron nitride coating
Technique.
Background technology
Photovoltaic generation is one of currently the most important clean energy resource, has great development potentiality.Restriction photovoltaic industry is sent out
The key factor of exhibition, is on the one hand that electricity conversion is low, is on the other hand high expensive.Photovoltaic silicon wafer is to produce solar-electricity
Pond and the stock of assembly, for produce photovoltaic silicon wafer polysilicon purity must (i.e. non-silicon impurity always contains more than 6N level
Amount is at below 1ppm), otherwise the performance of photovoltaic cell is by by the biggest negative effect.In recent years, polysilicon chip production technology
Having had marked improvement, polycrystalline cast ingot technology arrives from G4 (each silicon ingot weighs about 270 kilograms, can cut 4 × 4=16 silicon side) progress
G5 (5 × 5=25 silicon side) is the most progressive to G6 (6 × 6=36 silicon side).Further, the unit of produced polycrystalline silicon ingot casting
Volume incrementally increases, and yield rate increases, and the manufacturing cost of unit volume polycrystalline silicon ingot casting gradually reduces.
In actual production process, during solar energy polycrystalline silicon ingot casting, need to use silica crucible to load silicon material, and by silicon material throw
After entering silica crucible, the most also need preheated, fusing (also referred to as melt), long brilliant (also referred to as directional solidification crystallization), annealing,
The steps such as cooling, just can complete polycrystalline silicon ingot casting process.At present, during solar energy polycrystalline silicon ingot casting, the crucible spray used
Si is used during painting3N4Material is as sprayed on material, but because of Si3N4The heat conductivility of material itself is poor, unstability etc.
Feature, easily forms the oxygen content bottom Hard Inclusion, and ingot casting finished product during making ingot casting higher, has the quality of product very
Big impact.Meanwhile, Si3N4Although material can be effectively isolated silicon liquid and crucible reaction, but Si3N4After reacting with silicon liquid
Form red sector, be easily introduced impurity Si3N4And form Hard Inclusion, the quality of ingot casting finished product is affected the biggest.
It addition, annealing is an extremely important processing step during polycrystalline silicon ingot casting, the bad direct shadow of annealing effect
Ring the stress distribution within ingot casting finished product, the quality of polycrystalline silicon ingot casting finished product is affected bigger.And at present polysilicon is cast
When ingot makes annealing treatment, the method for neither one unification, standard and specification is available for following, and actual adding inevitably deposits man-hour
Operating the problems such as relatively more random, cost time length, annealing effect are poor, thus the matter that existing annealing process is to ingot casting finished product
Amount impact is the biggest.
Summary of the invention
The technical problem to be solved is for above-mentioned deficiency of the prior art, it is provided that a kind of based on nitridation
The polycrystalline silicon casting ingot process of boron coating, its processing step is simple, reasonable in design and realization is easy, using effect is good, by earthenware
Coat one layer of base coat with boron nitride as primary raw material bottom crucible, can effectively reduce crucible bottom oxygen content, and can be effective
Reduce the Hard Inclusion of ingot casting finished product, annealing process is adjusted simultaneously, the quality of ingot casting finished product can be effectively improved.
For solving above-mentioned technical problem, the technical solution used in the present invention is: a kind of polysilicon based on boron nitride coating
Casting ingot process, it is characterised in that this technique comprises the following steps:
Prepared by step one, crucible bottom coating, process is as follows:
Step 101, coating spraying liquid are prepared: by organic cementing agent, deionized water and boron nitride by 1: (2～2.5): (0.8
～1.2) mass ratio uniformly mix, obtain coating spraying liquid；
Step 102, spraying: use spraying equipment by the even application of coating spraying liquid described in step 101 to crucible
On bottom surface, portion, 1m in described crucible inner bottom surface2In region, in the described coating spraying liquid of spraying, the quality of contained boron nitride is
100g～200g；
Described crucible is quartz crucible for polycrystalline ingot furnace；
Step 103, drying: crucible described in step 102 is placed horizontally in drying plant, and uses described drying to set
Standby and under 80 DEG C～100 DEG C of temperature conditionss, the described coating spraying liquid being sprayed in crucible inner bottom surface is dried, obtain
Obtain base coat；
Step 2, polycrystalline silicon ingot casting, process is as follows:
Step 201, charging: in step one, in the crucible of band base coat, load silicon material；
Step 202, preheating: use described polycrystalline silicon ingot or purifying furnace that the silicon material being loaded in crucible is preheated, and by described
The heating-up temperature of polycrystalline silicon ingot or purifying furnace steps up to T1；Preheating time is 4h～6h, wherein T1=1125 DEG C～1285 DEG C；
Step 203, fusing: use described polycrystalline silicon ingot or purifying furnace that the silicon material being loaded in crucible is melted, fusion temperature
For T1～T2；Wherein T2=1540 DEG C～1560 DEG C；
After the silicon material in crucible all melts, by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T2, institute afterwards
The heating power stating polycrystalline silicon ingot or purifying furnace begins to decline, when the heating power of described polycrystalline silicon ingot or purifying furnace stops declining and continuing
Between after t, fusion process completes；Wherein t=20min～40min；
Step 204, long crystalline substance: be oriented solidifying after the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually decreased to T3 by T2
Gu, until completing long brilliant process；Wherein T3 is polysilicon crystal temperature and T3=1420 DEG C～1440 DEG C；
Step 205, annealing and cool down, process is as follows:
Step 2051, for the first time annealing: the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T4 through 50min～70min,
And it is incubated 2h～3h；Wherein, T4=1250 DEG C～1280 DEG C；
Step 2052, second time annealing: the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is dropped by T4 through 50min～70min
To T5, and it is incubated 2h～3h；T5=900 DEG C～950 DEG C；
Step 2053, cooling: cool to processed polycrystalline silicon ingot casting with the furnace room temperature, it is thus achieved that the described polycrystalline of machine-shaping
Silicon ingot casting.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: organic adhesive described in step 101
Agent is phenolic aldehyde-neoprene adhesive, epoxy adhesive, Instant adhesive, acrylic acid adhesive, polyvinyl alcohol adhesive, gathers
Vinyl acetate adhesive, AE SGA, butvar adhesive stick or glass cement；
Described boron nitride is hexagonal boron nitride.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: in step 202 in warm,
The heating power of described polycrystalline silicon ingot or purifying furnace is stepped up to P1, wherein P1=50kW～100kW；Earthenware described in step 203
After silicon material in crucible all melts, the heating power situation of change of described polycrystalline silicon ingot or purifying furnace is observed, treats described polycrystalline
The heating power of silicon ingot furnace drops to P2, and keeps P2 constant and after persistent period t, and melt process completes；Wherein, P2=
25kW～45kW.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: spraying equipment described in step 102
For liquid spray gun, drying plant described in step 103 is baking oven.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: crucible described in step 102 is vertical
Cube crucible；Crucible described in step 103 and described baking oven are all laid in level；
Described baking oven includes that casing, the bottom heater being laid in crucible bottom and four are laid in four of crucible respectively
The side heater of side-wall outer side, four described side heater are respectively positioned on above bottom heater, described bottom heater in
Level is laid, four described side heater all in vertically to laying；It is provided with on described bottom heater for crucible placement
Graphite cushion block.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: when spraying in step 102,
1m in described crucible inner bottom surface2In region in the described coating spraying liquid of spraying the quality of contained boron nitride be 100g～
150g。
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: when drying in step 103,
First use described drying plant that crucible is heated to 80 DEG C～100 DEG C, then carry out being incubated until being sprayed in crucible inner bottom surface
Described coating spraying liquid dry till.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: carry out in step 2051 for the first time
Annealing process neutralization procedure 2052 is carried out, in second time annealing process, all in described polycrystalline silicon ingot or purifying furnace, be filled with noble gas
And the air pressure in polycrystalline silicon ingot or purifying furnace is maintained at Q1, wherein Q1=180Pa～250Pa.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: many by being processed in step 2053
When crystal silicon ingot casting cools to room temperature with the furnace, cool down according to the rate of temperature fall of 90 DEG C/h～120 DEG C/h.
Above-mentioned a kind of polycrystalline silicon casting ingot process based on boron nitride coating, is characterized in that: after in step 204, long crystalline substance terminates,
The heating-up temperature of described polycrystalline silicon ingot or purifying furnace is T10, T10=1395 DEG C～1405 DEG C；Step 2051 is carried out anneal for the first time
Time, through 50min～70min, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T4 by T10.
The present invention compared with prior art has the advantage that
1, processing step is simple, reasonable in design and realizes conveniently, it is easy to grasping, input cost is relatively low.
2, the coating material used is by organic cementing agent, deionized water and boron nitride, and cost is relatively low and preparation is easy.
3, the coating material used, using boron nitride as primary raw material, can effectively increase crucible bottom heat-conducting effect, and
Can reduce crucible bottom oxygen content, Simultaneous Stabilization is good, is not easily formed Hard Inclusion during ingot casting, and ingot casting finished product can be effectively ensured
Quality.
4, the coating material used can effectively reduce the cost of polycrystalline silicon ingot casting, during due to boron originally as polycrystalline silicon ingot casting
A kind of adulterant used, but the cost of pure boron is at a relatively high；And prepare after using the coating material coating disclosed in the present invention
During polysilicon ingot crucible base coat, the doping of pure boron can be reduced, even avoid adding pure boron, it is thus possible to effectively drop
Low polycrystalline silicon ingot casting cost.
5, the painting method used is reasonable in design and realization is easy, using effect is good, can be easy, quickly in crucible bottom
Making one layer of base coat, and the base coat quality made is good, coating procedure is easily controllable.Meanwhile, the baking used
Stem structure is reasonable in design and cost is relatively low, using effect goods, and energy is easy, be rapidly completed the drying course of crucible bottom coating, and
And heats is good, crucible bottom uniform coating thickness and quality that machine-shaping can be effectively ensured are good.
When 6, melting during polycrystalline silicon ingot casting, after the silicon material in crucible all melts, control adding of ingot furnace
Hot temperature keeps constant, and is observed the time dependent curve of heating power (i.e. power curve) of ingot furnace；Wherein,
After the silicon material in crucible all melts, the power curve of ingot furnace begins to decline, and treats that the power curve of ingot furnace declines and walks
After flat 20min～40min, melt process completes, and carries out crystal growing stage afterwards.In actual mechanical process, bent by observed power
Line just can accurately determine the time point that melt process completes, and is i.e. switched to some switching time of crystal growing stage by the melting stage.Real
Border is easy and simple to handle, and realizes conveniently, and energy accurate assurance is switched to the switching time of crystal growing stage by the melting stage.It is to say,
The present invention stablizes ingot casting melt curve by extending the melt time, and after power curve walks flat 20min～40min, incision is long brilliant again
Stage, thus can accurately be melted to the switching time of crystal growing stage, stopped due to melt deficiency of time or melt time simultaneously
Long cause polycrystalline silicon ingot casting Quality Down, the problem such as cost increase.Further, during using the present invention to polycrystalline silicon ingot casting
After melt carries out accurate assurance to long brilliant switching time, can ensure that long brilliant quality and be finally made the conversion effect of cell piece
Rate；Meanwhile, crystal growth quality can be effectively improved, reduce viscous crucible rate, improve the conversion efficiency of solar battery sheet, can be effectively improved into
Product rate.
7, the annealing time during polycrystalline silicon ingot casting can effectively be reduced, with the lehr attendant during existing polycrystalline silicon ingot casting
Skill is compared, and each time annealing temperature is the most relatively low, and it is shorter to make annealing treatment the time, can be effectively improved polycrystalline silicon ingot casting efficiency.
8, annealing effect is good, can be effectively improved the yield rate of polycrystalline silicon ingot casting finished product, and, due to polycrystalline silicon ingot casting process
Carry out under vacuum conditions, and annealing process is typically all carried out under lower pressure environment, and under lower pressure environment, the fusing point fall of silicon
Low, the softening point of corresponding silicon also reduces, but in existing annealing process, still designs according to fusing point and the softening point of silicon under atmospheric pressure state
Annealing temperature, causes actual annealing temperature higher (under normal circumstances, the first annealing temperature is 1370 DEG C～1390 DEG C), and impact is moved back
Fire effect.And in the present invention, it is contemplated that under lower pressure environment, fusing point and the softening point of silicon all reduce, and the first annealing temperature is designed as
1250 DEG C～1280 DEG C, annealing temperature is reasonable in design, and can effectively save annealing time.Meanwhile, annealing temperature sets for the second time
Being calculated as 900 DEG C～950 DEG C, under this temperature conditions, silica undergoes phase transition, and silicon is prone to oxygen and reacts and generate silicon dioxide
Deng, can effectively discharge silicon crystal lattice stress during undergoing phase transition, thus reach the purpose of process annealing release silicon crystal lattice stress, with
Time can effectively reduce annealing time.
9, annealing process is reasonable in design and using effect good, and annealing temperature is reasonable in design, can be effectively improved polycrystalline silicon ingot casting
Stress state in finished product, and vertical gradient thermal field evenly can be formed, for larger-size ingot casting, annealing
During heterogeneity phantom uniform, annealing effect more preferably, can be prevented effectively from the annealing caused because of temperature heating-up temperature skewness
Effect is poor, affect the problems such as polycrystalline silicon ingot casting end product quality.
10, practical, it is simple to batch production, by coating one layer of end with boron nitride as primary raw material in crucible bottom
Portion's coating, can effectively reduce crucible bottom oxygen content, and can effectively reduce the Hard Inclusion of ingot casting finished product, improves the matter of ingot casting finished product
Amount；, by improving annealing process, annealing at twice, for the first time annealing is according to silicon soft under low-pressure state meanwhile
Changing some reasonable set annealing temperature, second time carries out annealing under cryogenic makes silicon crystal lattice stress effectively be discharged, and improves
Polycrystalline silicon ingot casting end product quality.Thus, the present invention mainly improves silicon in terms of crucible bottom coating and improvement annealing process two
Ingot casting end product quality, and improve the yield rate of silicon ingot casting finished product accordingly.
In sum, present invention process step is simple, reasonable in design and realization is easy, using effect is good, by crucible
One layer of base coat with boron nitride as primary raw material of bottom coating, can effectively reduce crucible bottom oxygen content, and can effectively subtract
The Hard Inclusion of few ingot casting finished product, is adjusted annealing process simultaneously, can improve the quality of ingot casting finished product.
Below by drawings and Examples, technical scheme is described in further detail.
Accompanying drawing explanation
Fig. 1 is the method flow block diagram of the present invention.
Fig. 2 is the structural representation of the crucible of band base coat of the present invention.
Fig. 3 is the structural representation of baking oven of the present invention.
Temperature when Fig. 4 is to use the present invention to melt and power.
Description of reference numerals:
1 crucible；2 base coat；3 bottom heaters；
4 side heater；5 graphite cushion blocks.
Detailed description of the invention
Embodiment 1
A kind of based on boron nitride coating polycrystalline silicon casting ingot process as shown in Figure 1, comprises the following steps:
Prepared by step one, crucible bottom coating, process is as follows:
Step 101, coating spraying liquid are prepared: organic cementing agent, deionized water and boron nitride are pressed the mass ratio of 1: 2.2: 1
Uniformly mixing, obtains coating spraying liquid；
Step 102, spraying: use spraying equipment by the even application of coating spraying liquid described in step 101 to crucible 1
On bottom surface, portion, 1m in described crucible 1 inner bottom surface2In region, in the described coating spraying liquid of spraying, the quality of contained boron nitride is
100g～150g；
Described crucible 1 is quartz crucible for polycrystalline ingot furnace；
Step 103, drying: crucible 1 described in step 102 is placed horizontally in drying plant, and uses described drying
Equipment and under 90 DEG C of temperature conditionss, the described coating spraying liquid being sprayed in crucible 1 inner bottom surface being dried, it is thus achieved that the end
Portion's coating 2, refers to Fig. 2；
Step 2, polycrystalline silicon ingot casting, process is as follows:
Step 201, charging: in step one, in the crucible 1 of band base coat 2, load silicon material；
Step 202, preheating: use described polycrystalline silicon ingot or purifying furnace that the silicon material being loaded in crucible 1 is preheated, and by described
The heating-up temperature of polycrystalline silicon ingot or purifying furnace steps up to T1；Preheating time is 5h, wherein T1=1200 DEG C；
Step 203, fusing: use described polycrystalline silicon ingot or purifying furnace that the silicon material being loaded in crucible 1 is melted, fusion temperature
For T1～T2；Wherein T2=1550 DEG C；
After the silicon material in crucible 1 all melts, by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T2, institute afterwards
The heating power stating polycrystalline silicon ingot or purifying furnace begins to decline, when the heating power of described polycrystalline silicon ingot or purifying furnace stops declining and continuing
Between after t, fusion process completes；Wherein t=30min；
Step 204, long crystalline substance: be oriented solidifying after the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually decreased to T3 by T2
Gu, until completing long brilliant process；Wherein T3 is polysilicon crystal temperature and T3=1430 DEG C；
Step 205, annealing and cool down, process is as follows:
Step 2051, for the first time annealing: through 1h, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T4, and is incubated
2.5h；Wherein, T4=1260 DEG C；
Step 2052, second time annealing: through 1h, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T5 by T4, and is incubated
2.5h；T5=920 DEG C；
Step 2053, cooling: cool to processed polycrystalline silicon ingot casting with the furnace room temperature, it is thus achieved that the described polycrystalline of machine-shaping
Silicon ingot casting.
Time actually used, can according to specific needs, to cementing agent organic in coating spraying liquid described in step 101, go from
The mass ratio of sub-water and boron nitride adjusts accordingly.
In the present embodiment, described organic cementing agent is phenolic aldehyde-neoprene adhesive.
Wherein, the kind of phenolic aldehyde-neoprene adhesive is more, mainly include anchor 801 seccotine, hundred glue, JX-
15-1 glue, FN-303 glue, CX-401 glue, XY-401 glue, CH-406 glue etc..Above-mentioned phenolic aldehyde-neoprene adhesive is commercially available
Commodity, can directly obtain.
Time actually used, described organic cementing agent can also be organic silicon adhesive, epoxy adhesive, Instant adhesive,
Acrylic acid adhesive, polyvinyl alcohol adhesive, Polyvinyl acetate adhesive, AE SGA, butvar adhesive are viscous
Agent or glass cement.
Wherein, organic silicon adhesive (also referred to as organosilicon adhesive) point one pack system, bi-component, room temperature vulcanization and heating sulfur
Change etc. multiple, the major product trade mark of room temperature vulcanized has 703,704, FS-203, GD-400 etc..According to solidification temperature, organic
Silica gel stick can be divided into hot setting, low-temperature setting and cold curing three class.Organic silicon adhesive of the present invention is low
Temperature curing organic silicon adhesive.
Epoxy adhesive is Vinylidene Chloride epoxy adhesive or furan modified epoxy adhesive.
Instant adhesive is also referred to as instant glue, and conventional is ethyl α-cyanoacrylate, product designation 502 glue；Medical
Alpha-cyanoacrylate butyl ester, product designation 504 glue.
Acrylic acid adhesive, commercially available kind has SA-200, AB glue, J-39, J-50, SGA-404, SGA etc..
In the present embodiment, described boron nitride is boron nitride powder.
In the present embodiment, described boron nitride is hexagonal boron nitride.
In the present embodiment, spraying equipment described in step 102 is liquid spray gun.
Time actually used, spraying equipment described in step 102 can also be other type of liquid spraying equipment.
In the present embodiment, drying plant described in step 103 is baking oven.
As it is shown on figure 3, crucible 1 described in step 102 is cube crucible；Crucible 1 described in step 103 and described baking oven
All lay in level；
Described baking oven includes casing, be laid in the bottom heater 3 bottom crucible 1 and four be laid in crucible 1 respectively
The side heater 4 of four side-wall outer side, four described side heater 4 are respectively positioned on above bottom heater 3, and described bottom adds
Hot device 3 is laid in level, four described side heater 4 all in vertically to laying；It is provided with on described bottom heater 3 for earthenware
The graphite cushion block 5 that crucible 1 is placed.
In the present embodiment, when step 102 sprays, 1m in described crucible 1 inner bottom surface2In region, spraying is described
In coating spraying liquid, the quality of contained boron nitride is 150g.
Preferably, when step 102 sprays, 1m in described crucible 1 inner bottom surface2The described coating of spraying in region
In spray coating liquor, the quality of contained boron nitride is 100g～150g.
During actually used, can according to specific needs, to 1m in crucible 1 inner bottom surface2The described painting of spraying in region
In layer spray coating liquor, the quality of contained boron nitride adjusts accordingly.
In the present embodiment, when step 103 is dried, first use described drying plant that crucible 1 is heated to 90 DEG C, then
Carry out being incubated till the described coating spraying liquid being sprayed in crucible 1 inner bottom surface is dried.
Actual when drying, can adjust accordingly drying temperature according to specific needs.
It is good etc. that boron nitride owing to containing in described base coat has good heat conductivity, good stability, resistance to elevated temperatures
Advantage, can effectively strengthen the heat-conducting effect bottom crucible 1, can be effectively improved melting efficiency, and being difficult to of crucible 1 bottom gas
Get rid of, can effectively reduce the oxygen content bottom crucible 1, make the oxygen content bottom ingot casting finished product reduce.Meanwhile, boron nitride and oxygen exist
Under high temperature, reaction generates B2O3And nitrogen dioxide gas (NO2) etc., the oxygen content bottom crucible 1 can be reduced further, and raw
The B become2O3Compare Si3N4Stable, it is not easily formed Hard Inclusion during ingot casting, thus can effectively reduce the Hard Inclusion of ingot casting finished product, with
Time can be effectively improved the minority carrier life time of ingot casting finished product, the quality of ingot casting finished product can be effectively improved.
In the present embodiment, step 2051 carries out carry out second time in first time annealing process neutralization procedure 2052 the most annealed
Cheng Zhong, is all filled with noble gas in described polycrystalline silicon ingot or purifying furnace and the air pressure in polycrystalline silicon ingot or purifying furnace is maintained at Q1, wherein
Q1=200Pa.
Further, described noble gas is argon.
Actual add man-hour, can according to specific needs the value size of T4, T5 and Q1 be adjusted accordingly respectively.
In the present embodiment, when step 2053 cools to processed polycrystalline silicon ingot casting with the furnace room temperature, according to 100 DEG C/h's
Rate of temperature fall cools down.
Actual when cooling down, can according to specific needs rate of temperature fall be adjusted accordingly.
Actual when carrying out polycrystalline silicon ingot casting, carry out the most under vacuum conditions, and annealing process is general all in low pressure
Carry out under environment.Owing to, under lower pressure environment, the fusing point of silicon reduces, and the softening point of corresponding silicon also reduces.And in existing annealing process,
Still design annealing temperature according to fusing point and the softening point of silicon under atmospheric pressure state, cause actual annealing temperature higher (under normal circumstances,
First annealing temperature is 1370 DEG C～1390 DEG C), affect annealing effect.And in the present invention, it is contemplated that under lower pressure environment, silicon is molten
Point and softening point all reduce, and the first annealing temperature is designed as 1250 DEG C～1280 DEG C, and annealing temperature is reasonable in design, and can be effective
Save annealing time.Meanwhile, annealing temperature is designed as 900 DEG C～950 DEG C for the second time, under this temperature conditions, and silica generation phase
Becoming, silicon is prone to oxygen and reacts and generate silicon dioxide etc., can effectively discharge silicon crystal lattice stress during undergoing phase transition, and improves casting
Ingot end product quality, thus reach the purpose of process annealing release silicon crystal lattice stress, can effectively reduce annealing time simultaneously.
Compared with conventional annealing process, lehr attendant's artistic skill disclosed by the invention is used to make the finished product of polycrystalline silicon ingot casting finished product
Rate improves more than 5%.
At present, polycrystalline silicon ingot casting method mainly has half casting process and fine melt ingot casting method two kinds, and half casting process is also referred to as
There is seed crystal ingot casting polycrystalline silicon process, refer to use grade silicon material to carry out epitaxial growth as nucleating center, cast low defect Gao Pin
The polycrystalline silicon ingot casting of matter；Fine melt ingot casting method is also referred to as without seed crystal ingot casting polycrystalline silicon process or without seed crystal efficient polycrystalline silicon technology, refers to
Non-silicon material is used to prepare shaggy heterogeneous forming core layer in crucible bottom, during by the roughness of control forming core layer with forming core
Degree of supercooling obtains bigger nucleation rate, casts low defect high-quality polycrystalline silicon ingot casting.Herein, polycrystalline silicon casting ingot process uses fine melt
Ingot casting method, thus according to the charging in conventional polysilicon fine melt ingot casting method, preheating, melt and long crystal method, complete polysilicon casting
The charging of ingot, preheating, melt and long brilliant process.Wherein, step 202 is carried out preheating, step 203 carries out melt and step
During carrying out long crystalline substance in 204, in described polycrystalline silicon ingot or purifying furnace, all it is filled with noble gas and by described polycrystalline silicon ingot or purifying furnace
Air pressure is maintained at Q2, wherein Q2=550mbar～650mbar.In the present embodiment, Q2=600mbar.
During actually used, can according to specific needs the value size of Q2 be adjusted accordingly.
In the present embodiment, described polycrystalline silicon ingot or purifying furnace is G5 type ingot furnace.Further, described polycrystalline silicon ingot or purifying furnace is specially Zhejiang
The G5 type ingot furnace that Jiang Jingsheng electromechanics limited company produces.Described crucible be silica crucible and its be G5 crucible, and raw
The polycrystalline silicon ingot casting that output is come is G5 ingot.
Time actually used, the charge of described silica crucible is about 600kg.
In the present embodiment, the charge of described silica crucible is 560kg.During actually used, can be according to concrete need
Want, the charge of described silica crucible is adjusted accordingly.
Meanwhile, during step 202 being carried out preheating and step 204 carry out long crystalline substance, in described polycrystalline silicon ingot or purifying furnace
It is filled with noble gas and described polycrystalline silicon ingot or purifying furnace internal gas pressure is maintained at Q2.
Actual when melting, can according to specific needs the value size of Q2, T2 and t be adjusted accordingly.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, oxygen content reduction by more than 60%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, energy bottom ingot casting
Being effectively improved ingot casting end product quality, yield rate is 76%.
Embodiment 2
In the present embodiment, as different from Example 1: in step 202 in warm, described ingot furnace added hot merit
Rate is stepped up to P1, wherein P1=50kW～100kW；After described in step 203, the silicon material in crucible all melts, to described
The heating power situation of change of ingot furnace is observed, and treats that the heating power of described ingot furnace drops to P2, and keeps P2 constant
And after persistent period t, melt process completes；Wherein, P2=25kW～45kW.
Further, when melting in step 203, process is as follows:
1st step, insulation: by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T1, and be incubated 0.4h～0.6h；
2nd step to the 5th step, heat up and pressurize: by first to rear point of four step by the heating-up temperature of described polycrystalline silicon ingot or purifying furnace by
T1 is gradually promoted to T6, and the heating-up time is 0.4h～0.6h；Temperature-rise period is filled with indifferent gas in described polycrystalline silicon ingot or purifying furnace
The air pressure of described polycrystalline silicon ingot or purifying furnace is also stepped up to Q2 by body；Wherein, T6=1190 DEG C～1325 DEG C；
6th step, heat up and pressurize for the first time: the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually promoted to by T6 T7 and
Heating-up time is 3.5h～4.5h, and polycrystalline silicon ingot or purifying furnace internal gas pressure described in temperature-rise period is maintained at Q2；Wherein, T7=1440 DEG C
～1460 DEG C；
7th step: second time heat up and pressurize: the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually promoted to by T7 T8 and
Heating-up time is 3.5h～4.5h, and polycrystalline silicon ingot or purifying furnace internal gas pressure described in temperature-rise period is maintained at Q2；Wherein, T8=1490 DEG C
～1510 DEG C；
8th step, third time heat up and pressurize: the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually promoted to by T8 T2 and
Heating-up time is 3.5h～4.5h, and polycrystalline silicon ingot or purifying furnace internal gas pressure described in temperature-rise period is maintained at Q2；Wherein, T2=1540 DEG C
～1560 DEG C；
9th step, insulation: by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T2, and be incubated 3.5h～4.5h；Insulation
During, described polycrystalline silicon ingot or purifying furnace internal gas pressure is maintained at Q2；
10th step, persistently insulation: by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T2, and be incubated 4h～8h, directly
Silicon material to crucible all melts；In insulating process, described polycrystalline silicon ingot or purifying furnace internal gas pressure is maintained at Q2.
In the present embodiment, the 6th step is carried out heat up for the first time and carry out in pressure maintaining period, in the 7th step second time heat up and
Carry out third time in pressure maintaining period, in the 8th step heat up and pressure maintaining period neutralization the 9th step carries out in insulating process, be both needed to institute
The heating power situation of change stating polycrystalline silicon ingot or purifying furnace is observed, and guarantees the heating power change of described polycrystalline silicon ingot or purifying furnace
Steadily.
Meanwhile, by rear point of four steps by the heating-up temperature of described polycrystalline silicon ingot or purifying furnace by T1 the most gradually in the 2nd step to the 5th step
When being promoted to T6, each step promotes temperature 5 DEG C～8 DEG C, and each step promotes and is both needed to 5min～10min.
Further, in step 202, preheating time is 5h；In warm, by the heating power of described polycrystalline silicon ingot or purifying furnace with
The rate of rise of 10kW/h～15kW/hkW/h steps up to P1.
In the present embodiment, in step 202 in warm, the heating power of described polycrystalline silicon ingot or purifying furnace is stepped up to
P1, wherein P1=75kW.
Actual when preheating, can according to specific needs, to the growth speed of heating power in preheating time, warm
The value size of rate and T1 and P1 adjusts accordingly.
In the present embodiment, after the silicon material in crucible all melts, by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace
At T2, and the time dependent curve of heating power (i.e. power curve) of described polycrystalline silicon ingot or purifying furnace is observed, refers to
Fig. 4.In Fig. 4, fine line is the time dependent curve of heating power of described polycrystalline silicon ingot or purifying furnace, and needing solid line is described polycrystalline
The time dependent curve of heating-up temperature of silicon ingot furnace, vertical line is alarming line when all melting of the silicon material in crucible.By Fig. 2
It can be seen that after the silicon material in crucible all melts, the power curve of described polycrystalline silicon ingot or purifying furnace begins to decline, treat described many
After the power curve of crystal silicon ingot furnace declines and walks flat 30min, melt process completes, and enters crystal growing stage afterwards；In i.e. Fig. 4
The time point that A point completes for melt process.
In actual mechanical process, just can accurately be determined the time point that melt process completes by observed power curve, i.e. by
Melting stage is switched to some switching time of crystal growing stage.Practical operation is easy, and realizes conveniently, and energy accurate assurance is by melting rank
Section is switched to the switching time of crystal growing stage.
In the present embodiment, after described in step 203, the silicon material in crucible all melts, described polycrystalline silicon ingot or purifying furnace is added
Thermal power situation of change is observed, and treats that the heating power of described polycrystalline silicon ingot or purifying furnace drops to P2, and keeps P2 constant and hold
After continuous time t, melt process completes；Wherein, P2=35kW.
Actual when melting, according to the difference of charge in described crucible, the size of P2 is accordingly at 25kW～45kW model
It is adjusted in enclosing.
In the present embodiment, the 1st step is incubated 0.5h；
The heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually promoted by T1 by the 2nd step to the 5th step by elder generation to rear point of four steps
To T6, the heating-up time is 0.5h (total time of the i.e. the 2nd step to the 5th step is 0.5h)；To described polycrystalline silicon ingot casting in temperature-rise period
It is filled with noble gas in stove and the air pressure of described polycrystalline silicon ingot or purifying furnace is stepped up to Q2；Wherein, T6=1250 DEG C；
The heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually promoted by T1 by the 2nd step to the 5th step by elder generation to rear point of four steps
During to T6, each step promotes temperature 5 DEG C～8 DEG C, and each step promotes and is both needed to 5min～10min；
Carrying out in 6th step heating up for the first time and during pressurize, the heating-up time is 4h, T7=1450 DEG C；
Carrying out second time in 7th step to heat up and during pressurize, the heating-up time is 4h, T8=1500 DEG C.
Carrying out third time in 8th step to heat up and during pressurize, the heating-up time is 4h；
When 9th step is incubated, it is incubated 4h；
When 10th step is persistently incubated, it is incubated 6h, until the silicon material in crucible all melts.
In the present embodiment, the 6th step is carried out heat up for the first time and carry out in pressure maintaining period, in the 7th step second time heat up and
Carry out third time in pressure maintaining period, in the 8th step heat up and pressure maintaining period neutralization the 9th step carries out in insulating process, be both needed to institute
The heating power situation of change stating polycrystalline silicon ingot or purifying furnace is observed, and guarantees the heating power change of described polycrystalline silicon ingot or purifying furnace
Steadily.
During it is to say, the 6th step to the 9th step melts, it is necessary to make power curve steadily advance, it is impossible to occur more
Significantly sags and crests, so can bring increasing of Hard Inclusion.
In the present embodiment, when heating up and pressurize in the 2nd step to the 5th step, process is as follows:
2nd step, the first step promote: by 1200 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1220 DEG C, and heat up
Time is 7min.
3rd step, second step promote: by 1220 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1235 DEG C, and heat up
Time is 8min.
4th step, the 3rd step promote: by 1235 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1242 DEG C, and heat up
Time is 5min.
5th step, the 4th step promote: by 1242 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1250 DEG C, and heat up
Time is 5min.
In the present embodiment, the 10th step being treated, the silicon material in crucible all melts and described polycrystalline silicon ingot or purifying furnace sends " fusing
Complete to report to the police " after, need manual intervention, the decline situation of power curve is observed, treats the power of described polycrystalline silicon ingot or purifying furnace
After curve declines and walks flat 30min, melt process completes, and manual intervention afterwards will be cut into crystal growing stage the melting stage.
In the present embodiment, when step 204 carries out long crystalline substance, after the heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T3, start
Being oriented solidification and enter long brilliant process, wherein T3 is polysilicon crystal temperature；Long brilliant process is as follows:
Step A1, by the heating and temperature control of polycrystalline silicon ingot or purifying furnace at T3, and be incubated 50min～70min；In this step,
The heat-insulation cage hoisting depth of described polycrystalline silicon ingot or purifying furnace is 60mm～100mm；
Step A2, by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T3, and be incubated 100min～140min；This step
In Zhou, the heat-insulation cage hoisting depth of described polycrystalline silicon ingot or purifying furnace is identical with the hoisting depth in step A1；
Step A3, by the heating and temperature control of polycrystalline silicon ingot or purifying furnace at T3, and be incubated 160min～200min；This step
In, the heat-insulation cage hoisting depth of described polycrystalline silicon ingot or purifying furnace is 105mm～115mm；
Step A4, by T3, the heating-up temperature of polycrystalline silicon ingot or purifying furnace being gradually decreased to T9, temperature fall time is 7h～9h；This step
In, the heat-insulation cage hoisting depth of described polycrystalline silicon ingot or purifying furnace is 205mm～215mm；Wherein, T9=1405 DEG C～1425 DEG C；
Step A5, by the heating and temperature control of polycrystalline silicon ingot or purifying furnace at T9, and be incubated 7h～9h；In this step, described many
The heat-insulation cage hoisting depth of crystal silicon ingot furnace is identical with the hoisting depth in step A4；
Step A6, by the heating and temperature control of polycrystalline silicon ingot or purifying furnace at T9, and be incubated 7h～9h；In this step, described many
The heat-insulation cage hoisting depth of crystal silicon ingot furnace is identical with the hoisting depth in step A4；
Step A7, by T9, the heating-up temperature of polycrystalline silicon ingot or purifying furnace being gradually decreased to T10, temperature fall time is 4h～5.5h；This
In step, the heat-insulation cage hoisting depth of described polycrystalline silicon ingot or purifying furnace is identical with the hoisting depth in step A4.Wherein, T10=
1398℃。
Actual add man-hour, can according to specific needs T3 be adjusted accordingly in the range of 1420 DEG C～1440 DEG C.Cause
And, after in step 204, long crystalline substance terminates, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is T10；Step 2051 is carried out move back for the first time
During fire, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T4 by T10.
Wherein, the heating-up temperature of polycrystalline silicon ingot or purifying furnace being gradually decreased in T9 process neutralization procedure A7 by T3 in step A4 will
The heating-up temperature of polycrystalline silicon ingot or purifying furnace is gradually decreased in T10 by T9, by reducing the heating power of four described side heater 4
Or reduce four described side heater 4 heat time heating time the heating-up temperature of polycrystalline silicon ingot or purifying furnace is reduced.
Time actually used, can according to specific needs T10 be adjusted accordingly in the range of 1395 DEG C～1405 DEG C.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 1.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 62%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 79%.
Embodiment 3
In the present embodiment, as different from Example 2: in step 202, preheating time is 4h and T1=1285 DEG C, P1=
100kW；In step 203 T2=1560 DEG C, t=20min, P1=45kW, Q2=650mbar；In 1st step, temperature retention time is
0.4h；In 2nd step to the 5th step T6=1325 DEG C, the heating-up time is 0.4h；In 6th step, T7=1460 DEG C and heating-up time are
3.5h；In 7th step, T8=1510 DEG C and heating-up time are 3.5h；In 8th step, the heating-up time is 3.5h；Temperature retention time in 9th step
For 3.5h；In 10th step, temperature retention time is 4h；
In the present embodiment, when heating up and pressurize in the 2nd step to the 5th step, process is as follows:
2nd step, the first step promote: by 1285 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1290 DEG C, and heat up
Time is 5min.
3rd step, second step promote: by 1290 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1295 DEG C, and heat up
Time is 5min.
4th step, the 3rd step promote: by 1295 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1315 DEG C, and heat up
Time is 9min.
5th step, the 4th step promote: by 1315 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1325 DEG C, and heat up
Time is 5min.
The heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T4 through 70min by step 2051, and is incubated 3h；Wherein, T4=
1250℃；The heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T5 by T4 through 70min by step 2052, and is incubated 3h, T5=900
℃；Q1=180Pa, T10=1395 DEG C；When cooling to processed polycrystalline silicon ingot casting with the furnace room temperature, according to the cooling of 90 DEG C/h
Speed cools down.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 2.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 60%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 74%.
Embodiment 4
In the present embodiment, as different from Example 2: in step 202, preheating time is 6h and T1=1125 DEG C, P1=
50kW；In step 203 T2=1540 DEG C, t=40min, P1=25kW, Q2=550mbar；In 1st step, temperature retention time is 0.6h；
In 2nd step to the 5th step T6=1190 DEG C, the heating-up time is 0.6h；In 6th step, T7=1440 DEG C and heating-up time are 4.5h；7th
In step, T8=1490 DEG C and heating-up time are 4.5h；In 8th step, the heating-up time is 4.5h；In 9th step, temperature retention time is 4.5h；The
In 10 steps, temperature retention time is 8h；
In the present embodiment, when heating up and pressurize in the 2nd step to the 5th step, process is as follows:
2nd step, the first step promote: by 1125 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1140 DEG C, and heat up
Time is 9min.
3rd step, second step promote: by 1140 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1155 DEG C, and heat up
Time is 8min.
4th step, the 3rd step promote: by 1155 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1175 DEG C, and heat up
Time is 10min.
5th step, the 4th step promote: by 1175 DEG C, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is promoted to 1190 DEG C, and heat up
Time is 9min.
In the present embodiment, the heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T4 through 50min by step 2051, and is incubated 2h,
T4=1280 DEG C；The heating-up temperature of polycrystalline silicon ingot or purifying furnace is down to T5 by T4 through 50min by step 2, and is incubated 2h, T5=950
℃；Q1=250Pa, T10=1405 DEG C；When cooling to processed polycrystalline silicon ingot casting with the furnace room temperature, according to the cooling of 120 DEG C/h
Speed cools down.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 2.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 65%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 72%.
Embodiment 5
In the present embodiment, as different from Example 2: organic cementing agent, deionized water and boron nitride are pressed by step 101
The mass ratio of 1: 2: 0.8 uniformly mixes, and obtains coating spraying liquid；Described organic cementing agent is organic silicon adhesive；In step 102
When spraying, 1m in described crucible 1 inner bottom surface2The quality of contained boron nitride in the described coating spraying liquid of spraying in region
For 100g；When step 103 is dried, use described drying plant and to being sprayed in crucible 1 under 80 DEG C of temperature conditionss
Described coating spraying liquid on bottom surface, portion is dried, and first uses described drying plant that crucible 1 is heated to 80 DEG C, then enters
Row insulation is till the described coating spraying liquid being sprayed in crucible 1 inner bottom surface is dried.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 2.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 64%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 73%.
Embodiment 6
In the present embodiment, as different from Example 1: organic cementing agent, deionized water and boron nitride are pressed by step 101
The mass ratio of 1: 2.5: 0.8 uniformly mixes, and obtains coating spraying liquid；Described organic cementing agent is epoxy adhesive；In step 102
When spraying, 1m in described crucible 1 inner bottom surface2The quality of contained boron nitride in the described coating spraying liquid of spraying in region
For 130g；When step 103 is dried, use described drying plant and to being sprayed in crucible 1 under 100 DEG C of temperature conditionss
Described coating spraying liquid on bottom surface, portion is dried, and first uses described drying plant that crucible 1 is heated to 100 DEG C, then
Carry out being incubated till the described coating spraying liquid being sprayed in crucible 1 inner bottom surface is dried.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 1.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 72%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 76%.
Embodiment 7
In the present embodiment, as different from Example 2: organic cementing agent, deionized water and boron nitride are pressed by step 101
The mass ratio of 1: 2.5: 1.2 uniformly mixes, and obtains coating spraying liquid；Described organic cementing agent is Instant adhesive；In step 102
When spraying, 1m in described crucible 1 inner bottom surface2The quality of contained boron nitride in the described coating spraying liquid of spraying in region
For 180g.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 2.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 65%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 69%.
Embodiment 8
In the present embodiment, as different from Example 1: organic cementing agent, deionized water and boron nitride are pressed by step 101
The mass ratio of 1: 2: 1.2 uniformly mixes, and obtains coating spraying liquid；Described organic cementing agent is acrylic acid adhesive；In step 102
When spraying, 1m in described crucible 1 inner bottom surface2The quality of contained boron nitride in the described coating spraying liquid of spraying in region
For 200g.
In the present embodiment, remaining method step and technological parameter are the most same as in Example 1.
In the present embodiment, by the annealing process in polycrystalline silicon casting ingot process is improved, and use polycrystalline silicon ingot casting
Stove and after utilizing the crucible 1 of band base coat 2 to carry out polycrystalline silicon ingot casting, the surface free from admixture of machine-shaping ingot casting finished product, without viscous
Crucible phenomenon, bottom ingot casting, oxygen content reduction by more than 60%, minority carrier life time ＞ 5.5us (microsecond), Hard Inclusion ratio ＜ 0.5%, become
Product rate is 68%.
The above, be only presently preferred embodiments of the present invention, not impose any restrictions the present invention, every according to the present invention
Any simple modification, change and the equivalent structure change that above example is made by technical spirit, all still falls within skill of the present invention
In the protection domain of art scheme.
Claims (10)
1. a polycrystalline silicon casting ingot process based on boron nitride coating, it is characterised in that this technique comprises the following steps:
Prepared by step one, crucible bottom coating, process is as follows:
Step 101, coating spraying liquid are prepared: by organic cementing agent, deionized water and boron nitride by 1: (2～2.5): (0.8～
1.2) mass ratio uniformly mixes, and obtains coating spraying liquid；
Step 102, spraying: use spraying equipment by the inside of the even application of coating spraying liquid described in step 101 to crucible (1)
On bottom surface, 1m in described crucible (1) inner bottom surface2In region, in the described coating spraying liquid of spraying, the quality of contained boron nitride is
100g～200g；
Described crucible (1) is quartz crucible for polycrystalline ingot furnace；
Step 103, drying: crucible described in step 102 (1) is placed horizontally in drying plant, and uses described drying to set
It is standby and under 80 DEG C～100 DEG C of temperature conditionss, the described coating spraying liquid being sprayed in crucible (1) inner bottom surface is dried,
Obtain base coat (2)；
Step 2, polycrystalline silicon ingot casting, process is as follows:
Step 201, charging: in step one, in the crucible (1) of band base coat (2), load silicon material；
Step 202, preheating: use described polycrystalline silicon ingot or purifying furnace that the silicon material being loaded in crucible (1) is preheated, and by described many
The heating-up temperature of crystal silicon ingot furnace steps up to T1；Preheating time is 4h～6h, wherein T1=1125 DEG C～1285 DEG C；
Step 203, fusing: using described polycrystalline silicon ingot or purifying furnace to melt the silicon material being loaded in crucible (1), fusion temperature is
T1～T2；Wherein T2=1540 DEG C～1560 DEG C；
After the silicon material in crucible (1) all melts, by the heating and temperature control of described polycrystalline silicon ingot or purifying furnace at T2, described afterwards
The heating power of polycrystalline silicon ingot or purifying furnace begins to decline, and treats that the heating power of described polycrystalline silicon ingot or purifying furnace stops declining and the persistent period
After t, fusion process completes；Wherein t=20min～40min；
Step 204, long crystalline substance: carry out directional solidification after the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is gradually decreased to T3 by T2, directly
To completing long brilliant process；Wherein T3 is polysilicon crystal temperature and T3=1420 DEG C～1440 DEG C；
Step 205, annealing and cool down, process is as follows:
Step 2051, for the first time annealing: through 50min～70min, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T4, and protects
Temperature 2h～3h；Wherein, T4=1250 DEG C～1280 DEG C；
Step 2052, second time annealing: the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T5 by T4 through 50min～70min,
And it is incubated 2h～3h；T5=900 DEG C～950 DEG C；
Step 2053, cooling: cool to processed polycrystalline silicon ingot casting with the furnace room temperature, it is thus achieved that the described polysilicon casting of machine-shaping
Ingot.
2. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1, it is characterised in that: step
Organic binder bond described in 101 be phenolic aldehyde-neoprene adhesive, epoxy adhesive, Instant adhesive, acrylic acid adhesive,
Polyvinyl alcohol adhesive, Polyvinyl acetate adhesive, AE SGA, butvar adhesive stick or glass cement；
Described boron nitride is hexagonal boron nitride.
3. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
In rapid 202 in warm, the heating power of described polycrystalline silicon ingot or purifying furnace is stepped up to P1, wherein P1=50kW～
100kW；After silicon material in crucible described in step 203 (1) all melts, the heating power of described polycrystalline silicon ingot or purifying furnace is changed
Situation is observed, and treats that the heating power of described polycrystalline silicon ingot or purifying furnace drops to P2, and keeps P2 constant and after persistent period t,
Melt process completes；Wherein, P2=25kW～45kW.
4. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
Described in rapid 102, spraying equipment is liquid spray gun, and drying plant described in step 103 is baking oven.
5. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 4, it is characterised in that: step
Crucible described in 102 (1) is cube crucible；Crucible described in step 103 (1) and described baking oven are all laid in level；
Described baking oven includes that casing, the bottom heater (3) being laid in crucible (1) bottom and four are laid in crucible (1) respectively
The side heater (4) of four side-wall outer side, four described side heater (4) are respectively positioned on bottom heater (3) top, institute
State bottom heater (3) to lay in level, four described side heater (4) all in vertically to laying；Described bottom heater
(3) the graphite cushion block (5) placed for crucible (1) it is provided with on.
6. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
When spraying in rapid 102,1m in described crucible (1) inner bottom surface2In region, in the described coating spraying liquid of spraying, institute is nitrogenous
The quality changing boron is 100g～150g.
7. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
When drying in rapid 103, first use described drying plant that crucible (1) is heated to 80 DEG C～100 DEG C, then carry out being incubated until
Till the described coating spraying liquid being sprayed in crucible (1) inner bottom surface is dried.
8. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
Carry out in rapid 2051 first time annealing process neutralization procedure 2052 being carried out, in second time annealing process, all cast to described polysilicon
It is filled with noble gas in ingot stove and the air pressure in polycrystalline silicon ingot or purifying furnace is maintained at Q1, wherein Q1=180Pa～250Pa.
9. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
When cooling to processed polycrystalline silicon ingot casting with the furnace room temperature in rapid 2053, carry out according to the rate of temperature fall of 90 DEG C/h～120 DEG C/h
Cooling.
10. according to a kind of based on boron nitride coating the polycrystalline silicon casting ingot process described in claim 1 or 2, it is characterised in that: step
After in rapid 204, long crystalline substance terminates, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is T10, T10=1395 DEG C～1405 DEG C；Step
When carrying out in 2051 annealing for the first time, through 50min～70min, the heating-up temperature of described polycrystalline silicon ingot or purifying furnace is down to T4 by T10.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107338474A (en) * | 2017-08-03 | 2017-11-10 | 晶科能源有限公司 | One kind reduces polycrystalline silicon ingot casting oxygen content method |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11189495A (en) * | 1997-12-26 | 1999-07-13 | Sumitomo Metal Ind Ltd | Silicon single crystal and its production |
| CN1742120A (en) * | 2002-12-06 | 2006-03-01 | 维苏威法兰西股份有限公司 | Vessel for holding silicon and method of producing the same |
| CN101886288A (en) * | 2010-07-09 | 2010-11-17 | 浙江碧晶科技有限公司 | Double-layer crucible for growing silicon single crystals by directional solidification method |
| CN101899703A (en) * | 2010-08-06 | 2010-12-01 | 浙江碧晶科技有限公司 | Crucible for growing crystalline silicon ingot and extracting silicon raw material of crystalline silicon ingot and preparation method and application thereof |
| CN103046129A (en) * | 2013-01-28 | 2013-04-17 | 天津英利新能源有限公司 | Polycrystalline silicon ingot casting process |
| CN103084325A (en) * | 2013-01-31 | 2013-05-08 | 天津英利新能源有限公司 | Crucible and coating method thereof |
| CN103305910A (en) * | 2012-03-15 | 2013-09-18 | 阿特斯(中国)投资有限公司 | Crucible for silicon ingot casting and preparation method of inner side coating thereof |
| CN103741214A (en) * | 2014-01-28 | 2014-04-23 | 西安华晶电子技术股份有限公司 | Polycrystalline silicon ingot casting process |
| CN103741215A (en) * | 2014-01-28 | 2014-04-23 | 西安华晶电子技术股份有限公司 | Ingot casting method of granular polysilicon |
-
2016
- 2016-08-19 CN CN201610695849.4A patent/CN106283183A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11189495A (en) * | 1997-12-26 | 1999-07-13 | Sumitomo Metal Ind Ltd | Silicon single crystal and its production |
| CN1742120A (en) * | 2002-12-06 | 2006-03-01 | 维苏威法兰西股份有限公司 | Vessel for holding silicon and method of producing the same |
| CN101886288A (en) * | 2010-07-09 | 2010-11-17 | 浙江碧晶科技有限公司 | Double-layer crucible for growing silicon single crystals by directional solidification method |
| CN101899703A (en) * | 2010-08-06 | 2010-12-01 | 浙江碧晶科技有限公司 | Crucible for growing crystalline silicon ingot and extracting silicon raw material of crystalline silicon ingot and preparation method and application thereof |
| CN103305910A (en) * | 2012-03-15 | 2013-09-18 | 阿特斯(中国)投资有限公司 | Crucible for silicon ingot casting and preparation method of inner side coating thereof |
| CN103046129A (en) * | 2013-01-28 | 2013-04-17 | 天津英利新能源有限公司 | Polycrystalline silicon ingot casting process |
| CN103084325A (en) * | 2013-01-31 | 2013-05-08 | 天津英利新能源有限公司 | Crucible and coating method thereof |
| CN103741214A (en) * | 2014-01-28 | 2014-04-23 | 西安华晶电子技术股份有限公司 | Polycrystalline silicon ingot casting process |
| CN103741215A (en) * | 2014-01-28 | 2014-04-23 | 西安华晶电子技术股份有限公司 | Ingot casting method of granular polysilicon |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107338474A (en) * | 2017-08-03 | 2017-11-10 | 晶科能源有限公司 | One kind reduces polycrystalline silicon ingot casting oxygen content method |
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