CN210506588U

CN210506588U - Polycrystalline silicon ingot furnace

Info

Publication number: CN210506588U
Application number: CN201921584301.8U
Authority: CN
Inventors: 吴君立; 黄纪德; 曹瑞宏; 龚宇琦; 夏志鹏; 朱惠君; 张昕宇; 金浩
Original assignee: Zhejiang Jinko Solar Co Ltd; Jinko Solar Co Ltd
Current assignee: Zhejiang Jinko Solar Co Ltd; Jinko Solar Co Ltd
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2020-05-12
Anticipated expiration: 2029-09-23

Abstract

The utility model discloses a polycrystalline silicon ingot furnace, which comprises: a crucible for carrying ingot silicon material; a DS block for supporting the crucible; detachably arranged on the surface of the DS block away from the bottom of the crucible for adjusting the bottom of the crucible Thermal field distribution heat preservation block and heat dissipation block; wherein, the distribution position of heat preservation block and heat dissipation block on the surface of the DS block can be adjusted. In the present application, inside the ingot furnace, the DS block used to support the crucible is provided with a heat preservation block and a heat dissipation block, which can not only maintain heat in the position where the heat dissipation is too fast, but also accelerate the heat dissipation in the position where the heat dissipation is too slow; compared with the prior art In the present application, the temperature of the thermal field is only adjusted through the thermal insulation layer. In this application, both the heat dissipation block and the heat preservation block are used for temperature adjustment, which has a better adjustment effect; Based on the different needs of the ingot casting process, the layout of the heat preservation block and the heat dissipation block is changed to improve the ability to adjust the thermal field of the ingot furnace.

Description

Polycrystalline silicon ingot furnace

Technical Field

The utility model relates to a polycrystal ingot casting technical field especially relates to a polycrystalline silicon ingot furnace.

Background

The polycrystalline silicon ingot casting process is one of the main process methods for obtaining pure silicon materials, and the obtained silicon materials can be used for manufacturing photovoltaic cells and producing and manufacturing other semiconductor devices. In the process of polysilicon ingot casting, temperature is one of the important factors influencing the growth of silicon ingots. At present, in various polycrystalline silicon ingot casting processes, in order to ensure that the temperature in an ingot casting furnace meets the growth requirement of a silicon ingot, a heat insulation layer is arranged on the ingot casting furnace according to the distribution position of a heater of the ingot casting furnace and the influence of the structure of the ingot casting furnace on heat dissipation. However, in the process of polysilicon ingot casting, different types of crystalline silicon products need to be matched with different processes, and the requirements for thermal field distribution in the ingot furnace are different, so that the mode of arranging the heat insulation layer on the ingot furnace in the prior art is difficult to meet the requirements of the existing ingot casting process.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a polycrystalline silicon ingot furnace has solved the poor problem of thermal field regulation performance in the ingot furnace among the prior art, has improved the performance of adjusting the thermal field.

In order to solve the technical problem, the utility model provides a polycrystalline silicon ingot furnace, include:

the crucible is used for bearing the ingot silicon material;

a DS block for supporting the crucible;

the heat preservation block and the heat dissipation block are detachably arranged on the surface of the DS block, which is far away from the bottom of the crucible, and are used for adjusting the distribution of a thermal field at the bottom of the crucible;

the distribution positions of the heat preservation block and the heat dissipation block on the surface of the DS block are adjustable.

Wherein, the radiating block is a graphite block.

Wherein the length of the radiating block is 5 cm-30 cm, the width is 5 cm-30 cm, and the thickness is 1.5 cm-6 cm; and the thicknesses of the heat dissipation blocks arranged on the DS block are not completely the same.

The surface of the heat dissipation block, which is far away from the DS block, is distributed with a plurality of grooves which are staggered with each other, the width of each groove is 4-20 mm, and the depth of each groove is 5-40 mm.

The heat preservation block comprises carbon fiber plates and a carbon fiber felt arranged between the two carbon fiber plates.

Wherein the length of the heat preservation block is 5 cm-30 cm, the width is 5 cm-30 cm, and the thickness is 3 cm-20 cm; and the thicknesses of the heat preservation blocks arranged on the DS block are not completely the same.

Wherein the DS block is provided with a bolt hole array; the heat preservation block with set up on the radiating block with bolt hole matched with screw in the bolt hole array.

The DS block is a graphite block, the length and the width of the DS block are both 1-1.5 m, the thickness of the DS block is 5-20 cm, the depth of a bolt hole is 2-5 cm, and the diameter of the bolt hole is 6-14 mm.

The heat preservation block is annularly arranged along the edge area of the DS block, and the heat dissipation block is arranged in the central area of the DS block.

The heat preservation block is arranged in three vertex areas of the DS block, and the heat dissipation block is arranged in a vertex area of the DS block where the heat preservation block is not arranged.

The utility model provides a polycrystalline silicon ingot furnace, include: the crucible is used for bearing the ingot silicon material; a DS block for supporting the crucible; the heat preservation block and the heat dissipation block are detachably arranged on the surface of the DS block, which is far away from the bottom of the crucible, and are used for adjusting the distribution of a thermal field at the bottom of the crucible; wherein, the distribution positions of the heat preservation block and the heat dissipation block on the surface of the DS block are adjustable.

In the application, the heat preservation block and the heat dissipation block are arranged on the DS block used for supporting the crucible inside the ingot furnace, so that heat preservation can be performed on positions with too fast heat dissipation, and heat dissipation can be accelerated on positions with too slow heat dissipation; compared with the prior art that the temperature of the thermal field is adjusted only through the heat insulation layer, the temperature is adjusted through the heat dissipation block and the heat insulation block at the same time, and the adjusting effect is better; in addition, the heat preservation block and the radiating block are connected in a detachable mode in the application, so that the layout of the heat preservation block and the radiating block is changed based on different requirements of an ingot casting process, and the adjusting capacity of a thermal field of the ingot casting furnace is improved.

Drawings

In order to clearly illustrate the embodiments or technical solutions of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a polysilicon ingot furnace provided by an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a DS block according to an embodiment of the present invention;

fig. 3 is a schematic view of a layout structure of a heat preservation block and a heat dissipation block provided by an embodiment of the present invention;

fig. 4 is a schematic view of another layout structure of the heat preservation block and the heat dissipation block provided by the embodiment of the present invention;

fig. 5 is a schematic structural diagram of a heat dissipation block 3 according to an embodiment of the present invention;

fig. 6 is a schematic structural view of the heat-insulating block provided by the embodiment of the present invention.

Detailed Description

At present, in a polycrystalline silicon ingot furnace, two main solutions are adopted for adjusting the temperature of the ingot furnace: firstly, the heat radiation of heater is blockked up to DS piece lateral part stopper heat insulating strip in hot region, secondly increases the inboard heat insulating strip of steel cage in the cold region, reduces the heat and loses.

The heat insulation strips of the side plugs of the DS blocks have influence on the operation of the furnace, so the heat insulation strips are required to be disassembled and assembled once every time the furnace is put out, and the heat insulation strips are made of carbon fiber materials, so the heat insulation strips are easy to wear and affect the heat insulation performance after being disassembled and assembled frequently; the heat dissipation of the heat at the heightened part is reduced by measuring the heat insulating strip in the high steel cage, but the steel cage needs to be lifted slowly along with the growth of the crystal, the lifting of the steel cage can weaken the heat insulating performance of the heightened side, and the temperature distribution gradually returns to an uneven state. Therefore, in practical applications, the adjustment capability of the two ways to the temperature distribution of the thermal field is very limited.

Secondly, for polycrystalline silicon ingot casting, the requirements of various ingot casting processes on a thermal field are different, for example, the semi-melting ingot casting process requires that the temperature at the bottom of a crucible is relatively uniform so as to form a flat or slightly convex solid-liquid interface and enable crystals to grow vertically; the single crystal-like process requires lower temperature in the middle and high temperature at the edge, forms a more convex solid-liquid interface, and inhibits dislocation multiplication at the splicing seams of the seed crystals and the side surfaces of the crucible. At present, the mode of adjusting the temperature in the ingot furnace basically prevents the edge position of the ingot furnace from radiating, and the requirements of different ingot casting processes cannot be met.

In addition, the conventional mode of regulating the temperature of the thermal field of the polycrystalline silicon ingot furnace still has the problem that the temperature is easy to neglect, the heaters can age to a certain extent along with the gradual increase of the service life of equipment, the heating capacity of each heater can be different if the service time of each heater is different, the heat insulation strips are arranged at present and are designed according to the same heating effect of each heater, the positions, the thicknesses and the like of the heat insulation strips cannot be regulated, and the temperature regulating capacity of the heat insulation strips on the thermal field in the ingot furnace is weaker and weaker along with the original longer service time of the polycrystalline silicon ingot furnace.

Finally, the adjustment of the thermal field of the polycrystalline silicon ingot furnace is to adjust the longitudinal temperature of the whole ingot furnace rather than to pay attention to the transverse temperature change gradient of the ingot furnace, and the ingot casting effect of polycrystalline silicon is also influenced to a certain extent.

Based on the problem, the utility model provides a polycrystalline silicon ingot furnace sets for temperature regulation's part on the DS piece to better regulation polycrystalline silicon ingot furnace ingot casting in-process thermal field distributes, satisfies various different ingot casting demands.

In order to make the technical field better understand the solution of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings and the detailed description. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1 and fig. 2, fig. 1 is a schematic structural diagram of a polysilicon ingot furnace provided by an embodiment of the present invention, and fig. 2 is a schematic structural diagram of a DS block provided by an embodiment of the present invention. The polycrystalline silicon ingot furnace may include:

the crucible 1 is used for bearing ingot silicon materials;

a DS block 2 for supporting the crucible;

the heat preservation block 4 and the heat dissipation block 3 are detachably arranged on the surface of the DS block 2, which is far away from the bottom of the crucible 1, and are used for adjusting the distribution of a thermal field at the bottom of the crucible 1;

wherein, the distribution positions of the heat preservation block 4 and the heat dissipation block 3 on the surface of the DS block 2 are adjustable.

Specifically, the distribution positions of the heat preservation block 4 and the heat dissipation block 3 on the DS block 2 can be adjusted and set according to the actual thermal field distribution of the bottom of the crucible in the ingot furnace and the thermal field distribution of ingot casting requirements. Fig. 1 and 2 only show one layout of the heat insulating block 4 and the heat dissipating block 3, and do not represent fixed arrangement positions of the two.

With the setting of directly laminating of heat preservation block 4 and radiating block 3 on DS piece 2 surface that deviates from crucible 1 in this application for 1 bottom of crucible can more be pressed close to heat preservation block 4 and radiating block 3, thereby reach better temperature regulation effect. And the heat preservation block 4 and the radiating block 3 are detachably arranged on the DS block 2, and the positions of the heat preservation block 4 and the radiating block 3 distributed on the DS block 2 are adjustable. In practical application, the distribution mode of the heat preservation block and the heat dissipation block can be set according to the practical requirement of the ingot casting process.

For example, in the existing semi-melting process of ingot casting high-efficiency mono-like crystals, a convex solid-liquid interface needs to be formed at the bottom of a crucible 1 to inhibit the splicing seams of seed crystals and dislocation proliferation of the edges of the crucible, namely, 10 cm-20 cm of solid seed crystals are reserved at the bottom of the crucible 1 and are not melted, the thickness of the solid seed crystals is gradually reduced from the center of the bottom of the crucible to the edges, and new crystals need to be grown on the basis of the seed crystals; in the transition stage from melting to crystal growth, whether the seed crystal at the bottom of the crucible 1 can not be melted and can be completely remained is related to the quality of the whole silicon ingot. Meanwhile, in the crystal growth stage, a slightly convex and uniform solid-liquid interface can effectively inhibit side type nuclei of the crucible 1, ensure the vertical growth of crystals, reduce impurity accumulation and improve the quality of silicon ingots; and a slightly convex and uniform solid-liquid interface is formed, so that the silicon material at the bottom of the crucible 1 is required to be kept in an unmelted solid state, the part above the bottom of the crucible 1 is molten into a liquid state, and the solid silicon material at the bottom of the crucible 1 is in a state of thick middle and thin edge. Therefore, the fast heat dissipation in the middle of the bottom of the crucible 1 and the slow heat dissipation at the edge need to be ensured.

Therefore, as shown in fig. 3, fig. 3 is a schematic view of a layout structure of a heat preservation block and a heat dissipation block provided by an embodiment of the present invention; in fig. 3, a ring of heat preservation blocks 4 are arranged at the edge position of the DS block 2, and a heat dissipation block 3 is arranged in the central area. Thereby realizing the effect of fast heat dissipation and slow heat dissipation at the edge of the central area at the bottom of the crucible 1.

Of course, the above arrangement is based on a symmetrical distribution in which the thermal field in the ingot furnace is ideal. Four heaters 5 are symmetrically arranged on four sides of the crucible 1 in the polycrystalline silicon ingot furnace, and one heater 5 is arranged at the top end of the crucible. Therefore, in an ideal state, the thermal fields of the horizontal plane in the ingot furnace are symmetrically distributed on the central axis of the crucible 1, and the thermal fields of the horizontal plane in the ingot furnace are generally required to be symmetrically distributed on the central axis in various ingot casting processes.

However, in practical applications, the heating effect of each heater 5 is not necessarily the same, for example, two adjacent heaters 5 of the heaters 5 on the four side positions of the crucible 1 are used for a longer time, and the other two heaters 5 are new heaters 5 which are just replaced, so that the heating effect of the new heater 5 may be better. Then the temperature of the included angle between the newly replaced heaters 5 may be higher, for this reason, as shown in fig. 4, fig. 4 is a schematic diagram of the layout structure of another heat preservation block and heat dissipation block provided by the embodiment of the present invention, in fig. 4, a heat dissipation block 3 may be disposed at the vertex angle position of the DS block 2 corresponding to the included angle, and the heat preservation block 4 is disposed at other positions.

The above embodiment is described only in two possible situations, in the actual ingot casting process, other distribution situations may exist in the ingot casting furnace, and the heat dissipation block 3 and the heat preservation block 4 on the DS block 2 may be adjusted differently according to actual needs, so as to achieve a better temperature adjustment effect.

Through set up position adjustable heat preservation block 4 and radiating block 3 on DS piece 2 in this application, realized the regulation to the temperature gradient of 1 bottom horizontal plane direction of crucible to can adjust heat preservation block 4 and radiating block 3's position according to actual need, satisfy the demand of different ingot casting technologies, improve the temperature regulation effect to in the polycrystalline silicon ingot casting furnace, be favorable to the growth quality of polycrystalline silicon.

The following is a detailed description of the specific arrangement of the heat-insulating block 4, the heat-dissipating block 3 and the DS block 2 of the present invention.

In an embodiment of the present invention, the heat dissipation block 3 may be a graphite block with high thermal conductivity.

In order to further strengthen the heat-dissipating ability of the heat-dissipating block, as shown in fig. 5, fig. 5 is a schematic structural diagram of the heat-dissipating block 3 provided by the embodiment of the present invention, a groove can be formed on the heat-dissipating block 3 to increase the surface area of the heat-dissipating block 3, and the width of the groove can be specifically set at 4 mm-20 mm, and the depth is 5 mm-40 mm, specifically the cross section of the groove can be an arc surface, and the area of the inner surface of the groove can be maximally covered.

In order to further increase the heat dissipation effect of the heat dissipation block 3, a plurality of strip-shaped grooves which are mutually crossed can be arranged on the surface of the heat dissipation block 3, so that the column structures are uniformly distributed on the surface of the whole heat dissipation block 3, and the surface area of the heat dissipation block 3 is large to the maximum extent.

The overall size of the heat dissipation block 3 may be, specifically, 5cm to 30cm in length, 5cm to 30cm in width, and 1.5cm to 6cm in thickness.

Specifically, the length and width of the heat dissipation block 3 should be as small as possible so as to be able to adjust the just-bottom temperature more finely, but if the length and width of the heat dissipation block 3 are too small, difficulty is brought to the mounting of the heat dissipation block 3, and for this reason, the preferred size range of the heat dissipation block 3 is provided in the present embodiment, and specifically, the length may be 5cm, 10cm, 15cm, 20cm, 25cm, 30 cm; the width can be 5cm, 10cm, 15cm, 20cm, 25cm, 30 cm.

To the radiating block 3 thickness direct relation to the radiating block the radiating effect good or bad of radiating block, in practical application, all radiating blocks 3 can all set up uniform size's length and width to the concatenation installation between the radiating block 3, but can set up the thickness of a plurality of differences to the radiating block 3 thickness, so when the concatenation sets up radiating block 3, can set up the radiating block 3 of thickness gradual change according to the thermal field gradient of 1 bottom of crucible, avoid the temperature sudden change.

For example, if a plurality of heatsinks 3 are provided in the central region of DS block 2, the closer to the center of DS block 2, the thicker the heatsinks 3 may be, and the thinner the heatsinks 3 may be, the further from the center, as desired for the semi-ingot casting process.

In another embodiment of the present invention, as shown in fig. 6, fig. 6 is a schematic structural diagram of the heat preservation block provided by the embodiment of the present invention, the heat preservation block 4 specifically includes two carbon fiber plates 41 and a carbon fiber felt 42 disposed between the two carbon fiber plates 41.

The carbon fiber plate 41 can read the carbon fiber felt 42 to play a role in protection, and the carbon fiber felt 42 is prevented from being pulled and damaged due to frequent disassembly and installation of the heat preservation block 4.

In order to facilitate the overall layout of the heat insulation block 4 and the heat dissipation block 3 on the DS block 2, the length and width of the heat insulation block 4 may be in a multiple relationship or identical, so the length of the heat insulation block 4 may range from 5cm to 30cm, the width may range from 5cm to 30cm, and the thickness may range from 1.5cm to 6 cm. And the heat insulation block 4 can also be provided with a plurality of different thicknesses like the heat dissipation block 3, so that the heat insulation block 4 with gradually changed thickness can be arranged according to the gradient of the thermal field at the bottom of the crucible 1.

For example, three rings of the insulating blocks 4 are arranged in the edge area of the DS block 2 based on the requirement of a semi-molten ingot casting process, and then the thickness of the three rings of the insulating blocks 4 is gradually increased from the inner ring to the outer ring.

In another embodiment of the present invention, in order to facilitate the detachable arrangement of the heat dissipation block 3 and the heat preservation block 4 on the DS block 2, a bolt hole array may be provided on the DS block 2; correspondingly, the heat-insulating block 4 and the heat-radiating block 3 are respectively provided with a first screw hole 41 and a second screw hole 31 which are matched with the bolt holes 21 in the bolt hole array, namely the heat-radiating block 3 and the heat-insulating block 4 can be detachably connected on the DS block 2 through bolts.

In order to ensure better heat transfer between the DS block 2, the heat preservation block 4 and the heat dissipation block 3 and ensure that the heat preservation block 4 and the heat dissipation block 3 have better temperature control and regulation effects, a graphite block can be used as the DS block 2, the DS block 2 can have the specific size of 1-1.5 m in length and width and 5-20 cm in thickness. Specifically, the bolt holes 21 on the DS block 2 may be 2cm to 5cm in diameter 6mm to 14 mm.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

Claims

1. A polycrystalline silicon ingot furnace is characterized by comprising:

the crucible is used for bearing the ingot silicon material;

a DS block for supporting the crucible;

2. The polysilicon ingot furnace of claim 1, wherein the heat sink is a graphite block.

3. The polysilicon ingot furnace according to claim 2, wherein the heat dissipation block has a length of 5cm to 30cm, a width of 5cm to 30cm and a thickness of 1.5cm to 6 cm; and the thicknesses of the heat dissipation blocks arranged on the DS block are not completely the same.

4. The polysilicon ingot furnace of claim 2, wherein a plurality of grooves are distributed on the surface of the heat dissipation block, which is away from the DS block, and the grooves are staggered with each other, and have a width of 4mm to 20mm and a depth of 5mm to 40 mm.

5. The polysilicon ingot furnace of claim 1, wherein the holding block comprises carbon fiber plates and a carbon fiber felt arranged between the two carbon fiber plates.

6. The polycrystalline silicon ingot furnace of claim 5, wherein the heat-insulating block has a length of 5cm to 30cm, a width of 5cm to 30cm and a thickness of 3cm to 20 cm; and the thicknesses of the heat preservation blocks arranged on the DS block are not completely the same.

7. The polycrystalline silicon ingot furnace of any one of claims 1 to 6, wherein the DS block is provided with a bolt hole array; the heat preservation block with set up on the radiating block with bolt hole matched with screw in the bolt hole array.

8. The polysilicon ingot furnace according to claim 7, wherein the DS blocks are graphite blocks, the DS blocks have a length and a width of 1-1.5 m and a thickness of 5-20 cm, the bolt holes have a hole depth of 2-5 cm and a diameter of 6-14 mm.

9. The polysilicon ingot furnace of any one of claims 1 to 6, wherein the heat retaining block is annularly arranged along an edge region of the DS block, and the heat dissipating block is arranged in a central region of the DS block.

10. The polysilicon ingot furnace according to any one of claims 1 to 6, wherein the heat retaining block is provided at three vertex regions of the DS block, and the heat dissipating block is provided at a vertex region of the DS block where the heat retaining block is not provided.