CN205188479U - Polycrystalline silicon ingot furnace - Google Patents

Abstract

The utility model discloses an enough make the temperature in the furnace body keep the polycrystalline silicon ingot furnace at a stable within range. This polycrystalline silicon ingot furnace is through setting up gaseous heating device in the intake pipe, gaseous heating device can heat the argon gas that gets into in the furnace body, cause great influence to the temperature in the furnace body in avoiding the lower argon gas entering furnace body of temperature, in -process in polycrystalline silicon ingot furnace work, can guarantee that the temperature in the furnace body keeps at a stable within range, avoid causing great influence to polycrystalline silicon ingot's growth, guarantee that the last silicon bulk quality that grows up to reaches higher quality level, additionally, utilize the heater strip can the rapid heating, and gaseous heating cavity is cylindrical, therefore, can guarantee that the argon gas has sufficient heat time, can so that all argon gass heated to same temperature, the heating effect is better. Be fit for the field popularization and application at polysilicon production equipment.

Description

A kind of polycrystalline silicon ingot or purifying furnace

Technical field

The utility model relates to production of polysilicon apparatus field, especially a kind of polycrystalline silicon ingot or purifying furnace.

Background technology

Transform light energy can be electric energy by solar cell, is an emphasis of modern Energy-saving Society development.According to the difference of body material, existing solar cell is divided into polysilicon solar cell, monocrystaline silicon solar cell and class monocrystaline silicon solar cell.Wherein, the transformation efficiency of monocrystaline silicon solar cell is high, but production cost is also high, the transformation efficiency 1%-2% lower than monocrystaline silicon solar cell of polysilicon solar cell, but its production cost is also low, and class monocrystaline silicon solar cell is the battery between monocrystalline silicon battery and polysilicon solar cell.Consider, solar cell is in the market still based on polysilicon solar cell.

The existing polycrystal silicon ingot for the production of polysilicon solar cell adopts casting ingot process usually, casting ingot process is generally realized by polycrystalline silicon ingot or purifying furnace, existing polycrystalline silicon ingot or purifying furnace comprises, comprise body of heater, body of heater is provided with aspirating hole, subiculum warming plate and stay-warm case is provided with in described body of heater, stay-warm case is placed on subiculum warming plate, stay-warm case and subiculum warming plate form heat insulating cage jointly, described stay-warm case is connected with the elevating lever that stay-warm case can be made to move up and down, crucible is provided with in described heat insulating cage, crucible guard boards, graphite base plate, graphite cover plate, side heater, top heater, heat exchange platform, described graphite base plate is placed on heat exchange platform, crucible is placed on graphite base plate, crucible guard boards is arranged on outside crucible, side heater is arranged on the outside of crucible guard boards, graphite cover plate is arranged on above crucible, top heater is arranged on above graphite cover plate, described heat exchange platform is fixed on bottom of furnace body by graphite column, the upper end of crucible guard boards is provided with exhaust emissions hole, also comprise inlet pipe, described inlet pipe is successively through body of heater, stay-warm case, top heater, stretch in crucible after graphite cover plate.

Current casting ingot process, after being first through spraying-stocking process, then enters ingot casting operation.

Spraying: can react with crucible after silicon material high temperature melting, introduce impurity, and cause sticky pot, affect the quality of silicon ingot, so need to spray one deck Silicon nitride solution between crucible and silicon material, utilize silicon nitride can effectively isolate silicon material and crucible, after Silicon nitride solution has sprayed, carry out hyperthermia drying again, by the moisture evaporation in Silicon nitride solution, crucible internal walls just can be made to adhere to one deck silicon nitride coating.

Charging: after crucible is dried, by fragmentary silicon material, in order, to require and silicon material loads in crucible by weight.

The crucible of charged just can carry out next step casting ingot process, first charged crucible is loaded in the body of heater of ingot furnace, after installing on request, by ingot furnace closing lid, the ingot furnace that closing lid is later, just forms the chamber of a sealing, by inner at ingot furnace for the sealed crucible installing silicon material, bring into operation casting ingot process, and whole casting ingot process divides 6 processes, vacuumizes-heat-melt-length crystalline substance-annealing-cooling.

S11, to vacuumize: the air in body of heater is taken away from aspirating hole, prevent the oxygen in the process heated up in air and silicon material generation oxidizing reaction, affect Ingot quality.Vacuumize is utilize vacuum pump to extract, the air in body of heater until reach opening of device requirement out.

S12, heating: after having vacuumized, enter the heating phase, and heating is to make silicon material heat up close to temperature of fusion fast, environment now in furnace chamber is vacuum environment, the water vapour by being attached to silicon material surface can being conducive to, being extracted out by the method vacuumized, and being rapidly heated.

S13, fusing: in melting process, need to fill argon gas in the chamber of sealing, avoid the silicon nitride coating generation decomposition reaction being attached to crucible internal walls, argon gas is filled with in body of heater by inlet pipe.After fusing starts, in body of heater, start inflation, after being inflated to specified pressure by processing sequence, start dynamically to keep.

S14, long crystalline substance: the silicon material melted, start to carry out long crystalline substance, long brilliant process is to rising by the stay-warm case of furnace interior, liquid-state silicon is dispelled the heat from bottom, the liquid-state silicon of bottom becomes solid state si, and along with the rising of stay-warm case and scattering and disappearing of heat, slowly upwards solidify, until whole silicon ingot has solidified.

S15, annealing: because long brilliant process starts in bottom, and rise with stay-warm case, until top, to push up because the reason of heat radiation like this at the end, and will exist must temperature head, generation internal stress.The effect of annealing is exactly under guarantee isoperibol, eliminates temperature head, thus eliminates internal stress.

S16, cooling: in furnace chamber, cool silicon ingot fast to tapping temperature.

Existing polycrystalline silicon ingot or purifying furnace comprises the body of heater with mezzanine space, body of heater is provided with aspirating hole, subiculum warming plate and stay-warm case is provided with in described body of heater, stay-warm case is placed on subiculum warming plate, stay-warm case and subiculum warming plate form heat insulating cage jointly, described stay-warm case is connected with the elevating lever that stay-warm case can be made to move up and down, crucible is provided with in described heat insulating cage, crucible guard boards, graphite base plate, graphite cover plate, side heater, top heater, heat exchange platform, described graphite base plate is placed on heat exchange platform, crucible is placed on graphite base plate, crucible guard boards is arranged on outside crucible, side heater is arranged on the outside of crucible guard boards, graphite cover plate is arranged on above crucible, top heater is arranged on above graphite cover plate, described heat exchange platform is fixed on bottom of furnace body by graphite column, the upper end of crucible guard boards is provided with exhaust emissions hole, also comprise inlet pipe, one end of described inlet pipe is connected with argon gas source, the other end is successively through body of heater, stay-warm case, top heater, stretch into after graphite cover plate in crucible, there is following problem in this polycrystalline silicon ingot or purifying furnace: first in actual use, in the process of polycrystalline silicon ingot or purifying furnace work, temperature in body of heater need remain in a stable scope, because existing polycrystalline silicon ingot or purifying furnace is all directly pass in body of heater by the argon gas of room temperature, because the temperature in body of heater is higher, the height of usual Dou Shiji Baidu, the argon gas of normal temperature enters in body of heater and will certainly cause larger impact to the temperature in body of heater, if temperature fluctuation changes greatly and can cause larger impact to the growth of silicon ingot in body of heater, the Ingot quality finally grown up to also can level uneven.

Utility model content

Technical problem to be solved in the utility model is to provide and a kind ofly the temperature in body of heater can be made to remain on polycrystalline silicon ingot or purifying furnace in a stable scope.

The utility model solves the technical scheme that its technical problem adopts: this polycrystalline silicon ingot or purifying furnace, comprise the body of heater with mezzanine space, body of heater is provided with aspirating hole, subiculum warming plate and stay-warm case is provided with in described body of heater, stay-warm case is placed on subiculum warming plate, stay-warm case and subiculum warming plate form heat insulating cage jointly, described stay-warm case is connected with the elevating lever that stay-warm case can be made to move up and down, crucible is provided with in described heat insulating cage, crucible guard boards, graphite base plate, graphite cover plate, side heater, top heater, heat exchange platform, described graphite base plate is placed on heat exchange platform, crucible is placed on graphite base plate, crucible guard boards is arranged on outside crucible, side heater is arranged on the outside of crucible guard boards, graphite cover plate is arranged on above crucible, top heater is arranged on above graphite cover plate, described heat exchange platform is fixed on bottom of furnace body by graphite column, the upper end of crucible guard boards is provided with exhaust emissions hole, also comprise inlet pipe, one end of described inlet pipe is connected with argon gas source, the other end is successively through body of heater, stay-warm case, top heater, stretch into after graphite cover plate in crucible, described inlet pipe is provided with gas-heating apparatus, described gas-heating apparatus comprises columnar shape basal, columniform gas heating cavity is provided with in described columnar shape basal, described columnar shape basal is provided with and the inlet mouth of gas heating cavity connects and air outlet, described inlet mouth is communicated with argon gas source, described air outlet is communicated with inlet pipe, the surface wrap of described columnar shape basal has heater strip, described heater strip is connected on power supply.

Further, be provided with temp controlled meter between described heater strip and power supply, be provided with temp probe in described gas heating cavity, described temp probe is connected with temp controlled meter.

Further, described graphite cover plate is provided with multiple through hole.

Be further, described bottom of furnace body is provided with overflow blanket, described overflow blanket is four-layer structure, be followed successively by knitting ceramic fiber blanket layer, knitting ceramic fiber blanket layer, ceramic fiber blanket layer, carbon carpet veneer from top to bottom, the thickness of described knitting ceramic fiber blanket layer is 10mm, the thickness of knitting ceramic fiber blanket layer is 10mm, the thickness of ceramic fiber blanket layer is 25mm, the thickness of carbon carpet veneer is 10mm.

Further, the upper surface of described overflow blanket is provided with overflow silk.

Further, described subiculum warming plate is provided with multiple overflow weir.

Further, carbon felt is provided with between described crucible and crucible guard boards.

The beneficial effects of the utility model are: this polycrystalline silicon ingot or purifying furnace by arranging gas-heating apparatus in inlet pipe, gas-heating apparatus can heat the argon gas entered in body of heater, the argon gas avoiding temperature lower enters in body of heater and causes larger impact to the temperature in body of heater, in the process of polycrystalline silicon ingot or purifying furnace work, the temperature that can ensure in body of heater remains in a stable scope, avoid causing larger impact to the growth of polycrystal silicon ingot, ensure that the Ingot quality finally grown up to reaches higher quality level, in addition, utilize heater strip can rapid heating, and gas heating cavity is cylindrical, thus, can ensure that argon gas has enough heat-up times, all argon gas can be made to be heated to same temperature, heats is better.

Accompanying drawing explanation

Fig. 1 is the structural representation of the utility model polycrystalline silicon ingot or purifying furnace;

Be labeled as in figure: body of heater 1, aspirating hole 2, subiculum warming plate 3, stay-warm case 4, elevating lever 5, crucible 6, crucible guard boards 7, graphite base plate 8, graphite cover plate 9, side heater 10, top heater 11, heat exchange platform 12, exhaust emissions hole 13, inlet pipe 14, argon gas source 15, through hole 17, overflow blanket 18, overflow weir 20, carbon felt 21, graphite column 22, gas-heating apparatus 33, columnar shape basal 331, gas heating cavity 332, , heater strip 334, power supply 335, temp controlled meter 336, temp probe 337.

Embodiment

Below in conjunction with accompanying drawing, the utility model is further illustrated.

As shown in Figure 1, this polycrystalline silicon ingot or purifying furnace, comprise the body of heater 1 with mezzanine space, body of heater 1 is provided with aspirating hole 2, subiculum warming plate 3 and stay-warm case 4 is provided with in described body of heater 1, stay-warm case 4 is placed on subiculum warming plate 3, stay-warm case 4 and subiculum warming plate 3 form heat insulating cage jointly, described stay-warm case 4 is connected with the elevating lever 5 that stay-warm case 4 can be made to move up and down, crucible 6 is provided with in described heat insulating cage, crucible guard boards 7, graphite base plate 8, graphite cover plate 9, side heater 10, top heater 11, heat exchange platform 12, described graphite base plate 8 is placed on heat exchange platform 12, crucible 6 is placed on graphite base plate 8, crucible guard boards 7 is arranged on outside crucible 6, side heater 10 is arranged on the outside of crucible guard boards 7, graphite cover plate 9 is arranged on above crucible 6, top heater 11 is arranged on above graphite cover plate 9, described heat exchange platform 12 is fixed on bottom body of heater 1 by graphite column 22, the upper end of crucible guard boards 7 is provided with exhaust emissions hole 13, also comprise inlet pipe 14, one end of described inlet pipe 14 is connected with argon gas source 15, the other end is successively through body of heater 1, stay-warm case 4, top heater 11, stretch in crucible 6 after graphite cover plate 9, described inlet pipe 14 is provided with gas-heating apparatus 33, described gas-heating apparatus 33 comprises columnar shape basal 331, columniform gas heating cavity 332 is provided with in described columnar shape basal 331, described columnar shape basal 331 is provided with the inlet mouth be communicated with gas heating cavity 332 and air outlet, described inlet mouth is communicated with argon gas source 15, described air outlet is communicated with inlet pipe 14, the surface wrap of described columnar shape basal 331 has heater strip 334, described heater strip 334 is connected on power supply 335.By arranging gas-heating apparatus 33 in inlet pipe 14, gas-heating apparatus 33 can heat the argon gas entered in body of heater 1, the argon gas avoiding temperature lower enters in body of heater 1 and causes larger impact to the temperature in body of heater 1, in the process of polycrystalline silicon ingot or purifying furnace work, the temperature that can ensure in body of heater 1 remains in a stable scope, avoid causing larger impact to the growth of polycrystal silicon ingot, ensure that the Ingot quality finally grown up to reaches higher quality level, in addition, utilize heater strip 334 can rapid heating, and gas heating cavity 332 is cylindrical, thus, can ensure that argon gas has enough heat-up times, all argon gas can be made to be heated to same temperature, heats is better.Be further, temp controlled meter 336 is provided with between described heater strip 334 and power supply 335, temp probe 337 is provided with in described gas heating cavity 332, described temp probe 337 is connected with temp controlled meter 336, the temperature in gas heating cavity 332 can be adjusted by temp controlled meter 336, the temperature of argon gas freely can be adjusted according to different situations, very easy to use.

In long brilliant process, crucible 6 inside needs to have certain thermograde from top to bottom, namely the temperature in crucible 6 reduces from the top down gradually, thermograde change is more obvious, the speed of growth of ingot casting is faster, the temperature of crucible 6 internal upper part mainly provides by top heater 11, the heat of top heater 11 is through being delivered in crucible 6 after graphite cover plate 9 again, due to the obstruct through graphite cover plate 9, temperature above graphite cover plate 9 is higher than the temperature below graphite cover plate 9, because the side heater 10 of existing polycrystalline silicon ingot or purifying furnace and top heater 11 are all unified controls, and in the long brilliant stage, temperature must control in certain scope, Here it is makes side heater 10 and top heater 11 all can only with identical power work, that is the heat that side heater 10 and top heater 11 provide is certain, to make the temperature of crucible 6 internal upper part higher, more heats just must be enable to be delivered in crucible 6 through graphite cover plate 9, thus make thermograde change in crucible 6 obvious, the utility model provides a kind of simple and effective way and changes obvious object to reach thermograde in crucible 6, namely on described graphite cover plate 9, multiple through hole 17 is provided with, by arranging multiple through hole 17 on graphite cover plate 9, the heat of top heater 11 can be unseparated be delivered in crucible 6 by through hole 17, the temperature of crucible 6 internal upper part can be increased for original, thus make the thermograde change in crucible 6 obvious, and then increase the speed of growth of ingot casting, this mode only need beat several through hole 17 on original graphite cover plate 9, substantially cost can not be increased, reequip also very convenient simultaneously.

Polycrystalline silicon ingot or purifying furnace in use, there is the phenomenon of silicon hydrorrhea stream sometimes, once there is silicon hydrorrhea stream, the silicon liquid overflowed can flow on the subiculum warming plate 3 of below along heat exchange platform 12, then silicon liquid drops onto the bottom of body of heater 1 again from the edge of subiculum warming plate 3, because silicon liquid temp is higher, silicon liquid is easy to body of heater 1 to burn thus accidents caused, in order to avoid body of heater 1 burns by the silicon liquid of overflow, bottom described body of heater 1, overflow blanket 18 is installed, the silicon liquid overflowed and body of heater 1 separate by overflow blanket 18, effectively prevent silicon liquid body of heater 1 is burnt, even if overflow blanket 18 burns by silicon liquid, now the temperature of silicon liquid is also lower, too large loss can not be caused to body of heater 1.In order to prevent silicon liquid, overflow blanket 18 is burnt, described overflow blanket 18 is four-layer structure, be followed successively by knitting ceramic fiber blanket layer, knitting ceramic fiber blanket layer, ceramic fiber blanket layer, carbon carpet veneer from top to bottom, the thickness of described knitting ceramic fiber blanket layer is 10mm, the thickness of knitting ceramic fiber blanket layer is 10mm, the thickness of ceramic fiber blanket layer is 25mm, the thickness of carbon carpet veneer is 10mm.

Know in time to make operator and whether there occurs silicon hydrorrhea stream, the upper surface of described overflow blanket 18 is provided with overflow silk, once there is silicon hydrorrhea stream, the overflow silk being arranged on overflow blanket 18 surface will be blown after the silicon liquid overflowed drops on overflow blanket 18, can send guard signal after overflow silk blows, alert carries out relating operation.Due to the silicon liquid of overflow flow to subiculum warming plate 3 after to flow to subiculum warming plate 3 edge could continue to dirty, just can monitor after so just causing overflow phenomena that for some time occurs, which adds the probability had an accident, therefore, silicon hydrorrhea flow phenomenon whether is there occurs in order to monitor quickly, described subiculum warming plate 3 is provided with multiple overflow weir 20, by arranging overflow weir 20 on subiculum warming plate 3, when the overflow blanket 18 that directly can flow to below after silicon liquid flows to subiculum warming plate 3 from overflow weir 20, and then blow being arranged on the overflow silk that overflow blanket 18 is arranged, thus reach the object of fast monitored.

In addition, more even in order to make crucible 6 be heated, carbon felt 21 is provided with between described crucible 6 and crucible guard boards 7, the heat of side heater 10 passes to crucible 6 through carbon felt 21 again through after crucible guard boards 7, because carbon felt 21 has good heat preservation and insulation, therefore, heat can not be delivered in crucible 6 by fast strikethrough carbon felt 21, heat can be made like this obtaining homogenizing through during carbon felt 21, thus crucible 6 is heated evenly, the qualification rate of product can be improved.

Claims (7)

1. a polycrystalline silicon ingot or purifying furnace, comprise the body of heater (1) with mezzanine space, body of heater (1) is provided with aspirating hole (2), subiculum warming plate (3) and stay-warm case (4) is provided with in described body of heater (1), stay-warm case (4) is placed on subiculum warming plate (3), stay-warm case (4) and subiculum warming plate (3) form heat insulating cage jointly, described stay-warm case (4) is connected with the elevating lever (5) that stay-warm case (4) can be made to move up and down, crucible (6) is provided with in described heat insulating cage, crucible guard boards (7), graphite base plate (8), graphite cover plate (9), side heater (10), top heater (11), heat exchange platform (12), described graphite base plate (8) is placed on heat exchange platform (12), crucible (6) is placed on graphite base plate (8), crucible guard boards (7) is arranged on crucible (6) outside, side heater (10) is arranged on the outside of crucible guard boards (7), graphite cover plate (9) is arranged on crucible (6) top, top heater (11) is arranged on graphite cover plate (9) top, described heat exchange platform (12) is fixed on body of heater (1) bottom by graphite column (22), the upper end of crucible guard boards (7) is provided with exhaust emissions hole (13), also comprise inlet pipe (14), one end of described inlet pipe (14) is connected with argon gas source (15), the other end is successively through body of heater (1), stay-warm case (4), top heater (11), stretch in crucible (6) after graphite cover plate (9), it is characterized in that: described inlet pipe (14) is provided with gas-heating apparatus (33), described gas-heating apparatus (33) comprises columnar shape basal (331), columniform gas heating cavity (332) is provided with in described columnar shape basal (331), described columnar shape basal (331) is provided with the inlet mouth and air outlet that are communicated with gas heating cavity (332), described inlet mouth is communicated with argon gas source (15), described air outlet is communicated with inlet pipe (14), the surface wrap of described columnar shape basal (331) has heater strip (334), described heater strip (334) is connected on power supply (335).

2. polycrystalline silicon ingot or purifying furnace as claimed in claim 1, it is characterized in that: between described heater strip (334) and power supply (335), be provided with temp controlled meter (336), be provided with temp probe (337) in described gas heating cavity (332), described temp probe (337) is connected with temp controlled meter (336).

3. polycrystalline silicon ingot or purifying furnace as claimed in claim 2, is characterized in that: described graphite cover plate (9) is provided with multiple through hole (17).

4. polycrystalline silicon ingot or purifying furnace as claimed in claim 3, it is characterized in that: described body of heater (1) bottom is provided with overflow blanket (18), described overflow blanket (18) is four-layer structure, be followed successively by knitting ceramic fiber blanket layer, knitting ceramic fiber blanket layer, ceramic fiber blanket layer, carbon carpet veneer from top to bottom, the thickness of described knitting ceramic fiber blanket layer is 10mm, the thickness of knitting ceramic fiber blanket layer is 10mm, the thickness of ceramic fiber blanket layer is 25mm, the thickness of carbon carpet veneer is 10mm.

5. polycrystalline silicon ingot or purifying furnace as claimed in claim 4, is characterized in that: the upper surface of described overflow blanket (18) is provided with overflow silk.

6. polycrystalline silicon ingot or purifying furnace as claimed in claim 5, is characterized in that: described subiculum warming plate (3) is provided with multiple overflow weir (20).

7. polycrystalline silicon ingot or purifying furnace as claimed in claim 6, is characterized in that: be provided with carbon felt (21) between described crucible (6) and crucible guard boards (7).