CN219195198U

CN219195198U - Ingot single crystal silicon growth equipment with multiple partition areas and adjustable vertical temperature gradient

Info

Publication number: CN219195198U
Application number: CN202122008473.4U
Authority: CN
Inventors: 陈建明; 胡君梅
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-08-24
Filing date: 2021-08-24
Publication date: 2023-06-16
Anticipated expiration: 2031-08-24

Abstract

The utility model belongs to the field of crystal growth equipment, and provides multi-partition vertical temperature gradient adjustable ingot single crystal silicon growth equipment, which comprises a growth area surrounded by an outer partition board in the middle of a crucible, and a plurality of growth partition boards divided into a plurality of growth partition boards by an inner partition board in the growth area, wherein seed crystals can be selectively fixed at the bottom of each growth partition board, polysilicon raw materials are covered above the seed crystals, each growth partition board is an independent crystal growth area, and all crystals synchronously grow. The outer partition plate in the growth equipment is used for blocking polycrystal precipitated from the inner wall of the crucible from extending to the center of the crucible, the arrangement of the inner partition plate avoids the grain boundary generated by the intercrossing growth between adjacent crystals, the proportion of single crystals of silicon crystals is greatly improved, a plurality of heating devices with independent power control are arranged between the growth area of the crystals and the heat preservation layer, the temperature gradient around the crucible is regulated together, the crystal growth interface and the growth speed are controlled, and the smooth progress of crystal growth is ensured.

Description

Ingot single crystal silicon growth equipment with multiple partition areas and adjustable vertical temperature gradient

Technical Field

The utility model relates to ingot single crystal silicon growth equipment with multiple partition areas and adjustable vertical temperature gradient, and belongs to the technical field of crystal growth.

Background

Photovoltaic power generation is a sustainable clean energy method obtained by converting solar energy into electric energy, and has undergone a development process of approximately 20 years, and crystalline silicon photovoltaic power generation takes the absolute dominant role.

The crystalline silicon comprises two products, namely ingot polycrystalline silicon and Czochralski monocrystalline silicon, and the ingot polycrystalline silicon has the advantages of low production cost, high degree of automation and low light attenuation speed, but the cell efficiency is low due to high defect density of the ingot polycrystalline silicon; the Czochralski silicon cell has high efficiency, but has high production cost, and needs to be monitored in real time by experienced process personnel.

Over the last decade, a method that perfectly combines the advantages of ingot polysilicon and czochralski silicon has been desired, and thus, the development of ingot silicon technology has begun. After undergoing the development stages of ingot polycrystal, small-grain high-efficiency polycrystal, quasi-single crystal (quasi-single crystal) and ingot single crystal silicon, although the single crystal proportion is improved, a polycrystal phenomenon still exists, and the crystal quality is not comparable with that of Czochralski single crystal silicon.

The traditional preparation method of the ingot monocrystalline silicon comprises the following steps: a layer of monocrystalline seed crystal is paved at the bottom of the crucible, silicon materials are filled above the seed crystal, the upper part of the seed crystal is melted by heating, and the temperature is slowly reduced to enable the crystal to grow upwards. In order to mark the relative position of the crucible and the crystal, the interior of the crucible is divided into 25 square areas with different sizes, which are respectively marked as A, B and C, wherein the area A represents four corner areas of the crucible, the area B represents the area which is contacted with the four inner walls of the crucible except the area A, the area C represents the central area close to the crucible, the sectional area of the area A is larger than the sectional area of the area B, the sectional area of the area C is the smallest, polycrystal mainly exists in the area A and the area B, the source of polycrystal is that during the crystal growth process, the polycrystal is precipitated from the inner wall of the supercooled crucible and extends inwards, finally the grown crystal ingot is cut into independent crystal columns according to the preset area position, and the area A, B, C in the diagram of the position distribution of the crystal columns after the crystal ingot cutting is shown in the diagram of FIG. 2; in addition, a small amount of polycrystal also appears at the junctions of all the sides of the rectangular columns in the A, B, C area, because two adjacent columns can mutually cross and grow in the crystal growth process, and the polycrystalline area is left behind after the adjacent columns extend into the opposite columns.

Through the development of more than ten years, the ingot single crystal silicon technology still can not solve the problem of polycrystalline defects well, and the cost performance is behind that of Czochralski single crystal silicon; particularly, in the last five years, ingot single crystal silicon technology is input to Czochralski single crystal silicon technology in competition, so that more than thousand polycrystal ingot furnaces are in a production stopping state, and huge waste of resources is caused.

Disclosure of Invention

Aiming at the defects existing in the prior art, the utility model aims to provide ingot single crystal silicon growth equipment with multiple partitions and adjustable vertical temperature gradient, so as to improve the single crystal proportion of ingot single crystal silicon, and the ingot single crystal silicon growth equipment is realized.

The ingot single crystal silicon growth equipment with the adjustable vertical temperature gradient of multiple partitions comprises a furnace body, a heat preservation component arranged on the inner wall of the furnace body in a sliding manner, a base arranged in the furnace body, a crucible fixedly connected to the base, a crucible cover plate matched with the crucible, a heating device arranged on the periphery of the crucible, a vent pipe connected with the crucible through the furnace body, and a plurality of inner partitions which are fixed in the crucible and divide the interior of the crucible into grid-shaped independent growth partitions, wherein seed crystals are arranged at the bottom of each growth partition, and polysilicon raw materials are covered above the seed crystals; the bottom inside the crucible is divided by the inner partition plate, so that seed crystals with certain areas are mutually independent, mutual interference in the growth process is avoided, and the probability of generating polycrystalline silicon from gaps between the seed crystals is reduced.

Preferably, the crucible further comprises an outer partition plate arranged at the outer side of the inner partition plate and close to the inner wall of the crucible, the outer partition plate divides the crucible into a partition area and a growth area, and the growth partition area is arranged in the growth area; in the growth process of the monocrystalline silicon crystal, the heating device can heat the crucible, but because the temperature difference exists between the crucible and the seed crystal, the temperature of the inner wall of the crucible is lower than that of the seed crystal, polycrystal can be separated out from the inner wall surface of the side of the crucible, and as the crystal growth is carried out, the polysilicon gradually extends to the inside of the crystal, so that the proportion of polycrystal from bottom to top is gradually increased, the outer partition plate is arranged to divide the crucible into a spacing area and a growth area, the effect of preventing the polysilicon generated on the inner wall surface of the side of the crucible from spreading to the growth area in the inside is achieved, and the growth rate of the monocrystalline silicon in the growth area of the crucible is ensured and improved.

Preferably, the heat insulation assembly comprises an upper heat insulation layer, a lower heat insulation layer and a side heat insulation layer, and the side heat insulation layer is slidably connected to the inner side wall of the furnace body through a side heat insulation layer lifting mechanism; the heat preservation mutually independent sets up, and side heat preservation accessible side heat preservation elevating system adjusts from top to bottom, plays the heat preservation effect of changing the crucible through adjusting the position of side heat preservation.

Preferably, the lower heat-insulating layer and the base are both connected in the furnace body in a sliding way through a base lifting mechanism; the lower heat preservation and the base are slidably connected in the furnace body through the base lifting mechanism, so that the crucible and the lower heat preservation can be adjusted in the vertical direction, the distance between the crucible and the heating device is changed, a certain temperature gradient is formed in the crucible, and the growth temperature requirements of monocrystalline silicon at different stages are met.

Preferably, the crucible is fixedly connected with the base through a crucible fixing piece, the heating device comprises an upper heater fixed between the upper heat-insulating layer and the crucible cover plate, a side heater fixed between the side heat-insulating layer and the crucible fixing piece, and a lower heater slidingly connected between the lower heat-insulating layer and the base, the upper heater penetrates through the upper heat-insulating layer to be fixedly connected with the top cover of the furnace body, the side heater penetrates through the side heat-insulating layer to be fixedly connected with the side wall of the furnace body, and the lower heater is slidingly connected between the lower heat-insulating layer and the base through a lower heater lifting mechanism; the lower heater is connected in the furnace body in a sliding way through the lower heater lifting mechanism, plays a role in adjusting the position of the lower heater in the furnace body, and the heating degree of the bottom of the crucible is also different through adjusting the position of the lower heater, so that the temperature in the crucible is further adjusted in the mode.

Preferably, the number of the upper heater, the side heater and the lower heater is not limited and the power can be independently adjusted, the total power of the heating device is defined as P, the power of the upper heater is defined as P1, the power of the side heater is defined as P2, the power of the lower heater is defined as P3, and the total power P of the heating device satisfies p=p1+p2+p3.

Preferably, the outer separator and the inner separator are made of high temperature resistant materials, the matrix material is one of quartz glass, quartz ceramic, silicon nitride ceramic, boron nitride ceramic and graphite products, the surface of the matrix material can be coated with a high temperature resistant coating, and the high temperature resistant coating can be one of silicon nitride and barium oxide; when the crystal grows, the crucible is in a high temperature state, the silicon melt in the high temperature state reacts with the quartz crucible, and the silicon nitride and the barium oxide play a role in isolating the quartz crucible from the silicon melt.

Preferably, the cross section of the growth partition area is one or more of a combination of mutually independent round, oval, rectangle, cube, hexagon, octagon and trapezoid, and the cross section of the same growth partition area in different longitudinal spaces can be in various shapes.

Preferably, seed crystals are fixed at the bottom of the growth isolation region, and the horizontal sectional area of the seed crystals is 0.01-100% of the horizontal sectional area of the growth isolation region.

The utility model has the beneficial effects that:

(1) The utility model relates to ingot single crystal silicon growth equipment with multiple partition areas and adjustable vertical temperature gradients, which is provided with a plurality of heating devices with independent power control between a crystal growth area and a heat preservation layer, wherein the temperature gradients around a crucible are regulated together, and the seed crystal fusion, a crystal growth interface and a growth speed are controlled to ensure that crystal growth is smoothly carried out.

(2) The utility model relates to ingot single crystal silicon growth equipment with multiple partition areas and adjustable vertical temperature gradient, wherein a side heat-insulating layer and a crucible of the growth equipment can move up and down to assist a heating device to participate in the adjustment of the temperature gradient, and the crystal growth process can be flexibly controlled when a larger kilogram-level ingot is grown.

Drawings

Other features, objects and advantages of the present utility model will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:

FIG. 1 is a schematic diagram showing the structure of a conventional ingot single crystal silicon growing apparatus used in the background art and comparative example of the present utility model;

FIG. 2 is a schematic top view of a conventional ingot single crystal silicon growth apparatus in accordance with the background of the utility model;

FIG. 3 is a schematic view of the longitudinal structure of the ingot single crystal silicon growing apparatus according to the present utility model;

fig. 4 is a schematic top view of the ingot single crystal silicon growing apparatus according to the present utility model in a crucible.

In the figure: the device comprises a furnace body 1, an upper heat-insulating layer 2, a lower heat-insulating layer 3, a side heat-insulating layer 4, a side heat-insulating layer 5 lifting mechanism, a base 6, a base 7 lifting mechanism, an 8 crucible, a 9 crucible fixing piece, a 10 crucible cover plate, an 11 upper heater, a 12 side heater, a 13 lower heater, a 14 lower heater lifting mechanism, a 15 vent pipe, a 16 outer partition plate, a 17 inner partition plate, an 18 partition area, a 19 growth area, a 20 growth partition area and 21 seed crystals.

Detailed Description

The utility model is further described in connection with the following detailed description, in order to make the technical means, the creation characteristics, the achievement of the purpose and the effect of the utility model easy to understand.

Example 1

As shown in fig. 3 and fig. 4, this embodiment is a specific implementation manner of a multi-partition vertical temperature gradient adjustable ingot single crystal silicon growth apparatus.

The ingot single crystal silicon growth equipment with adjustable vertical temperature gradient in multiple partitions comprises a furnace body 1, an upper heat preservation layer 2, a lower heat preservation layer 3, a side heat preservation layer 4, a base 6, a crucible 8, a crucible cover plate 10, a heating device, a vent pipe 15, an outer partition plate 16, an inner partition plate 17 and a detection assembly (not shown in the figure), wherein the upper heat preservation layer 2 and the lower heat preservation layer 3 are respectively arranged on the inner wall of the furnace body 1 in different modes; the inner partition plates 17 are provided with a plurality of inner partition plates 17, the inner partition plates 17 are fixed in the crucible 8 and divide the interior of the crucible 8 into grid-shaped independent growth partition areas 20, seed crystals 21 are arranged at the bottom of each growth partition area 20, and polysilicon raw materials are covered above the seed crystals 21; an outer partition 16 is provided outside the inner partition 17 near the inner wall of the crucible 8, and the outer partition 16 divides the crucible 8 into a partition 18 and a growth region 19, the growth partition 20 being divided inside the growth region 19.

The upper heat preservation layer 2, the lower heat preservation layer 3 and the side heat preservation layer 4 are made of one of graphite products, metal screens, zirconia or alumina products, the side heat preservation layer 4 is slidably connected to the inner side wall of the furnace body 1 through a side heat preservation layer lifting mechanism 5, and the lower heat preservation layer 3 and the base 6 are slidably connected in the furnace body 1 through a base lifting mechanism 7.

The crucible 8 is fixedly connected with the base 6 through a crucible fixing piece 9.

The heating device comprises an upper heater 11 fixed between the upper heat preservation layer 2 and the crucible cover plate 10, a side heater 12 fixed between the side heat preservation layer 4 and the crucible fixing piece 9, and a lower heater 13 slidably connected between the lower heat preservation layer 3 and the base 6, wherein the upper heater 11 penetrates through the upper heat preservation layer 2 to be fixedly connected with the top cover of the furnace body 1, and the side heater 12 penetrates through the side heat preservation layer 4 to be fixedly connected with the side wall of the furnace body 1. The lower heater 13 is slidably connected between the lower insulating layer 3 and the base 6 through the lower heater lifting mechanism 14, the number of the upper heater 11, the side heater 12 and the lower heater 13 is not limited, the power can be independently adjusted, the total power of the heating device is defined as P, the power of the upper heater 11 is defined as P1, the power of the side heater 12 is defined as P2, the power of the lower heater 13 is defined as P3, and the total power P of the heating device satisfies p=p1+p2+p3.

The outer partition plate 16 and the inner partition plate 17 are made of high-temperature resistant materials, the substrate material is one of quartz glass, quartz ceramic, silicon nitride ceramic, boron nitride ceramic and graphite products, and the surface of the substrate material can be selectively covered with coatings such as silicon nitride, barium oxide and the like. The cross section of the growth isolation region 20 is one or a combination of a plurality of mutually independent circles, ellipses, rectangles, cubes, hexagons, octagons and trapezoids, and the cross section of the same growth isolation region 20 in different longitudinal spaces can be in various shapes, in this embodiment, the growth isolation region 20 is square with the same area, the seed crystal 21 is fixed at the bottom of the growth isolation region 20, and the horizontal cross section of the seed crystal 21 is 0.01-100% of the horizontal cross section of the growth isolation region 20.

The detection assembly comprises a small corrugated pipe with a quartz rod inside, the corrugated pipe is provided with a lifting mechanism, a through hole is formed in the top of the furnace body 1, the corrugated pipe slides in the through hole, the melting degree of the seed crystal 21 and the growth height of crystals are judged by measuring the position of the seed crystal 21 in the crucible 8, and the growth height value M of the crystals after the growth is completed is judged according to the volume of the crucible 8 and experience.

Example 2

In the embodiment, the specification of the furnace body 1 is a G5 polycrystalline ingot furnace, the outer baffle plate 16 and the inner baffle plate 17 are made of silicon nitride materials, the thickness of the seed crystal 21 fixed at the bottom of the growth baffle zone is 30mm, and the height after the crystal growth is finished is 400mm.

Example 3

In the embodiment, the specification of the furnace body 1 is G5 polycrystalline ingot furnace, the outer baffle 16 is made of quartz ceramic material with the surface covered with silicon nitride coating, the inner baffle 17 is made of silicon nitride material, the thickness of seed crystal 21 fixed at the bottom of the growth baffle zone is 25mm, and the height after the crystal growth is finished is 400mm.

While the fundamental and principal features of the utility model and advantages of the utility model have been shown and described, it will be apparent to those skilled in the art that the utility model is not limited to the details of the foregoing exemplary embodiments, but may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the utility model being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.

Claims

1. The utility model provides a many partition vertical temperature gradient adjustable ingot casting monocrystalline silicon growth equipment, including furnace body (1), slip setting heat preservation subassembly on furnace body (1) inner wall, set up base (6) in furnace body (1), crucible (8) of fixed connection on base (6), with crucible (8) looks adaptation crucible apron (10), set up at crucible (8) periphery heating element, link up furnace body (1) and crucible (8) continuous breather pipe (15), its characterized in that: the polycrystalline silicon crucible is characterized by further comprising a plurality of inner partition plates (17) which are fixed in the crucible (8) and divide the interior of the crucible (8) into grid-shaped independent growth partitions (20), seed crystals (21) are arranged at the bottom of each growth partition (20), and polycrystalline silicon raw materials are covered above the seed crystals (21).

2. The multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growth apparatus of claim 1, wherein: the crucible also comprises an outer partition plate (16) arranged outside the inner partition plate (17) and close to the inner wall of the crucible (8), the crucible (8) is divided into a partition area (18) and a growth area (19) by the outer partition plate (16), and the growth partition area (20) is arranged in the growth area (19).

3. The multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growth apparatus of claim 2, wherein: the heat preservation assembly comprises an upper heat preservation layer (2), a lower heat preservation layer (3) and a side heat preservation layer (4), wherein the side heat preservation layer (4) is slidably connected to the inner side wall of the furnace body (1) through a side heat preservation layer lifting mechanism (5).

4. A multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growth apparatus as set forth in claim 3, wherein: the lower heat preservation layer (3) and the base (6) are both connected in the furnace body (1) in a sliding way through the base lifting mechanism (7).

5. A multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growing apparatus according to claim 2 or 4, wherein: crucible (8) pass through crucible mounting (9) and base (6) fixed connection, heating device is including fixing last heater (11) between last heat preservation (2) and crucible apron (10), fix side heater (12) between side heat preservation (4) and crucible mounting (9), sliding connection is lower heater (13) between lower heat preservation (3) and base (6), go up heater (11) and run through the top cap fixed connection of last heat preservation (2) and furnace body (1), side heater (12) run through side heat preservation (4) and the lateral wall fixed connection of furnace body (1), lower heater (13) are through lower heater elevating system (14) sliding connection between lower heat preservation (3) and base (6).

6. The multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growing apparatus of claim 5, wherein: the number of the upper heater (11), the side heater (12) and the lower heater (13) is not limited, the power can be independently adjusted, the total power of a heating device is defined as P, the power of the upper heater (11) is defined as P1, the power of the side heater (12) is defined as P2, the power of the lower heater (13) is defined as P3, and the total power P of the heating device meets P=P1+P2+P3.

7. The multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growing apparatus of claim 6, wherein: the cross section of the growth isolation region (20) is one or a combination of a plurality of mutually independent circles, ellipses, rectangles, cubes, hexagons, octagons and trapezoids, and the cross section of the same growth isolation region (20) in different longitudinal spaces can be in various shapes.

8. The multi-compartment vertical temperature gradient adjustable ingot single crystal silicon growing apparatus of claim 7, wherein: seed crystals are fixed at the bottom of the growth isolation region (20), and the horizontal sectional area of the seed crystals is 0.01-100% of the horizontal sectional area of the growth isolation region (20).