CN115679439A - Single crystal furnace charging system and charging control method - Google Patents

Abstract

The invention discloses a single crystal furnace feeding system and a feeding control method, relates to the technical field of solar photovoltaic, and aims to solve the technical problems that in the process of supplying a solid silicon material, when the solid silicon material falls into a melt in a crucible, large impact is generated, the liquid level of the melt is oscillated, and the growth of a single crystal is influenced. The single crystal furnace charging system comprises a charging device, a melting device and a material guide device; the melting device comprises a first melting cavity and a second melting cavity which are communicated with each other; the discharge port of the feeding device is communicated with the first melt cavity and is used for providing raw materials for the melt device; the melting device is used for melting the raw materials to obtain a molten material; the second melting cavity is communicated with a feeding port of the material guide device, a discharging port of the material guide device extends into the single crystal furnace, and the melting material in the second melting cavity enters a crucible of the single crystal furnace through the material guide device.

Description

Single crystal furnace charging system and charging control method

Technical Field

The invention relates to the technical field of solar photovoltaics, in particular to a single crystal furnace charging system and a charging control method.

Background

Currently, processes for pulling single crystal silicon include CZ (Czochralski ) and CCZ (Continuous crystal pulling) processes.

When pulling a single crystal silicon rod by the CCZ process, a feeder device is usually installed outside the single crystal furnace, and silicon material is continuously fed into a crucible of the single crystal furnace while pulling is maintained, thereby ensuring continuous pulling.

However, during the process of supplying the silicon material, when the solid silicon material directly falls into the melt in the crucible, large mechanical impact and thermal impact can be generated, the liquid level of the melt is oscillated, and the temperature gradient change is caused at the crystal growth interface, so that the growth of the single crystal is influenced.

Disclosure of Invention

Based on the above, the invention aims to provide a single crystal furnace feeding system and a feeding control method, so as to solve the technical problem that in the process of supplying a solid silicon material, when the solid silicon material falls into a melt in a crucible, large impact is generated, the liquid level of the melt is oscillated, and the growth of a single crystal is influenced.

The invention provides a single crystal furnace charging system, which comprises a charging device, a melting device and a material guide device, wherein the melting device is arranged on the charging device; the melting device comprises a first melting cavity and a second melting cavity which are communicated with each other;

the discharge port of the feeding device is communicated with the first melting cavity and is used for providing raw materials for the melting device; the melting device is used for melting the raw materials to obtain a molten material;

the second melt cavity is communicated with a feeding port of the material guide device, a discharge port of the material guide device extends into the single crystal furnace, and the melt in the second melt cavity enters a crucible of the single crystal furnace through the material guide device.

Under the condition that adopts above-mentioned scheme, feeding device's discharge gate is linked together with first melt cavity for provide the raw materials to the melt device, the melt device is used for melting the raw materials, in order to obtain the melt. Because the second melting cavity is communicated with the feeding port of the material guide device, and the discharge port of the material guide device extends into the single crystal furnace, the melting material in the melting device can enter the crucible of the single crystal furnace through the material guide device. Based on the technical scheme, the raw materials are melted outside the single crystal furnace, then the liquid melt obtained after the raw materials are melted is added into the crucible of the single crystal furnace, and the liquid melt is added, so that the impact of the solid raw materials on the melt existing in the crucible is smaller, and the liquid level of the melt in the crucible is basically not corrugated. And the molten raw material is added into the crucible, so that the influence on the temperature gradient of a thermal field and convection in the crucible is small due to heat absorption caused by melting, and stable crystal pulling is facilitated.

Furthermore, the melting device in the charging system of the single crystal furnace provided by the invention comprises a first melting cavity and a second melting cavity which are communicated. The discharge port of the feeding device is communicated with the first melting cavity for supplying raw materials to the first melting cavity, and the second melting cavity is communicated with the feeding port of the material guiding device for supplying melting materials to the crucible of the single crystal furnace through the material guiding device. Therefore, when raw materials are added into the first melting material cavity, the liquid level of the second melting material cavity cannot generate ripples, so that the stability of melting materials flowing into the single crystal furnace is guaranteed, and the quality of a single crystal silicon rod is further guaranteed.

In one possible implementation manner, the material melting device comprises a material containing part, a heating part and a separating part; the heating portion is used for heating the material containing portion, and the separating portion is arranged in the material containing portion and used for separating the material containing portion into a first molten material cavity and a second molten material cavity.

Under the condition of adopting the technical scheme, the melting device comprises the independent heating part, so the heating part can be independently controlled, and the melting process of the raw materials in the material containing part can be independently controlled. Based on the control, the heating part can be controlled differently according to the different quality of the raw materials added into the material containing part, thereby improving the controllability of the feeding system of the single crystal furnace.

In a possible implementation manner, the bottom of the first melting cavity is communicated with the bottom of the second melting cavity, and the feeding port of the material guiding device is not lower than the bottom of the separating part.

Under the condition of adopting above-mentioned technical scheme, under the bottom of first cavity and the bottom of second melt cavity intercommunication's the condition, the melt can flow between first melt cavity and the first melt cavity of second, and can guarantee that first melt cavity and the first melt cavity liquid level of second are flat mutually. On the basis, the material inlet of the material guiding device is not lower than the bottom of the partition part, and the partition part limits the solid raw material in the first melt cavity, so that the solid raw material does not exist in the melt entering the crucible of the single crystal furnace, the liquid level of the melt in the crucible is further ensured not to fluctuate during feeding, and the quality of the pulled silicon single crystal rod is ensured.

In a possible implementation manner, the material guiding device comprises a material guiding part and a heating part arranged on the material guiding pipe. The first end of the material guiding piece is communicated with the second melting cavity, and the second end of the material guiding piece extends into the single crystal furnace. The first end of the material guiding member is not lower than the bottom of the partition part. Wherein, the heating element can be an electromagnetic induction heating element.

Under the condition that adopts above-mentioned technical scheme, above-mentioned heating member is arranged in heating to the melt that flows in the passage to guarantee that the melt in the passage can not crystallize, thereby ensure that the melt has stable mobility in the passage.

In a possible implementation manner, the heating element is an electromagnetic induction heating coil, the material guiding element is a material guiding pipe, and the heating coil is arranged around the periphery of the material guiding pipe.

Under the condition that adopts above-mentioned technical scheme, electromagnetic induction heating coil encircles in the periphery of passage to carry out even heating to the melt in the passage, based on this, can the omnidirectional to the melt heating in the passage, take place the crystallization with the melt of avoiding any region in the passage.

In a possible implementation manner, a feeding port of the material guiding device is communicated with the top of the second melting material cavity.

Under the condition of adopting the technical scheme, the molten material overflows to the feeding port of the material guide device through the top of the second molten material cavity and then enters the crucible in the single crystal furnace. The raw material entering the melting device is solid raw material, and the solid raw material is more dense relative to the melting material, so the solid raw material is positioned at the bottom of the melting device. In the invention, the molten material overflows from the top of the second molten material cavity to the material inlet of the material guide device, so that solid raw materials can be further prevented from entering the material guide device.

In a possible implementation manner, the single crystal furnace feeding system further comprises a material blocking device, and the material blocking device is arranged at a material inlet of the material guiding device and used for adjusting the flow speed and flow of molten materials flowing into the material guiding device.

Furthermore, the material blocking device comprises a material blocking part and a driving part in driving connection with the material blocking part. The material blocking part is arranged at the material inlet of the material guiding device and used for adjusting the area of the material inlet of the material guiding device under the driving of the driving part.

Under the condition of adopting the technical scheme, the material blocking end of the material blocking device is arranged at the material inlet of the material guiding device and is used for adjusting the flow speed and the flow of the molten material flowing into the material guiding device, so that the stability of the liquid level of the molten material in the crucible of the single crystal furnace is further controlled.

In a possible implementation, the raw material is a solid raw material and the feeding device comprises a feeding portion. The pan feeding mouth of feeding portion is used for receiving solid-state raw materials, and the discharge gate and the relative setting of first melt cavity of feeding portion for provide solid-state raw materials to first melt cavity. The discharge port of the feeding part is higher than the top height of the melting device, and the discharge port of the material guide device is higher than the top height of a crucible in the single crystal furnace.

Under the condition of adopting the technical scheme, the discharge hole of the feeding part is higher than the top height of the melting device, and the discharge hole of the material guide device is higher than the top height of the crucible in the single crystal furnace. Based on this, solid raw materials in the feeding portion can utilize self gravity feeding portion to get into the guide device, and the melt in the guide device also can get into the crucible through self gravity, need not with the help of any power unit, also need not to make any special design to the structure of feeding portion and guide device.

In one possible implementation, the feeding device further comprises a feeding portion and a vibrating feeder.

The discharge port of the raw material supply part is arranged opposite to the feeding end of the feeding part and used for providing solid raw materials for the feeding part, and the discharge end of the feeding part is arranged opposite to the first melting cavity.

The vibration feeder is connected with the feeding part and used for providing vibration force to the feeding part so as to enable solid raw materials with preset mass in the feeding part to enter the melting device.

Furthermore, the vibration feeder is arranged at one end of the feeding part, which is far away from the melting device.

Under the condition of adopting above-mentioned technical scheme, can provide the vibrations power to the feeding portion through vibrations charging means to make the solid raw materials of the predetermined quality in the feeding portion get into the melt device. Based on the above, the quality of the solid raw material added into the melting device can be controlled by adjusting the vibration parameters of the vibration feeder, so that the controllability of the feeding system of the single crystal furnace is improved.

In one possible implementation manner, the vibrating feeder is further in communication connection with a controller of the melting device, and is used for providing a vibrating parameter to the controller, and the controller is used for controlling a heating parameter of a heating part of the melting device according to the vibrating parameter.

The vibrating feeder is used for providing vibrating parameters for the controller under the condition that the technical scheme is adopted, and the controller is used for controlling the heating parameters of the heating part of the melting device according to the vibrating parameters. Based on the above, the heating parameters of the heating part in the melting device can be set according to the quality of the raw material added into the melting device, so that the raw material added into the melting device can be fully melted, and the quality of the pulled silicon single crystal rod can be further improved.

In a possible implementation manner, the raw material is a rod-shaped raw material, and the feeding device comprises a lifting driving part.

The pulling driving part is positioned above the melting device and is connected with the first end of the rod-shaped raw material, the second end of the rod-shaped raw material extends into the melting device, and the pulling driving part is used for controlling the length of the rod-shaped raw material extending into the melting device.

Under the condition of adopting the technical scheme, when the raw material is a rod-shaped raw material, the pulling driving part is positioned above the melting device and is used for extending the rod-shaped raw material into the melting device in a pulling mode and controlling the length of the rod-shaped raw material extending into the melting device. By controlling the length of the rod-shaped raw material extending into the melting device, the quality of the rod-shaped raw material melted by the melting device in unit time can be controlled, and thus the controllability of the single crystal furnace feeding system is improved.

In a possible implementation manner, the feeding device further comprises a quality sensor, and the quality sensor is arranged on the pulling driving part and used for acquiring the current quality of the rod-shaped raw material connected with the pulling driving part in real time.

The mass sensor is also in communication with a controller of the melting device for sending a current mass of the rod-shaped feedstock to the controller, and the controller is configured to control heating parameters of a heating portion of the melting device based on the current mass of the rod-shaped feedstock.

In the above-described aspect, the weight sensor is configured to acquire a current mass of the rod-shaped raw material connected to the pulling driving unit in real time and send the current mass of the rod-shaped raw material to the controller of the melting device, and the controller is configured to control a heating parameter of the heating unit of the melting device based on the current mass of the rod-shaped raw material and a mass of the rod-shaped raw material at a previous time. Based on the above, the heating parameters of the heating part in the melting device can be set according to the quality of the rod-shaped raw material entering the melting device, so that the raw material added into the melting device can be fully melted, and the quality of the pulled single crystal silicon rod can be further improved.

In a second aspect, the invention also discloses a charging control method, which comprises the following steps:

controlling a feeding device to provide raw materials to the first melting cavity;

controlling the melting device to melt the raw materials to obtain a molten material; and the molten material enters the single crystal furnace through the material guide device.

The advantageous effects of the second aspect and its various implementations in the present invention are the same as those of the first aspect or any possible implementation of the first aspect, and are not described herein again.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and do not limit the invention. In the drawings:

FIG. 1 shows a block diagram of a charging system of a single crystal furnace according to an embodiment of the invention;

FIG. 2 is a block diagram showing another single crystal furnace charging system provided by an embodiment of the invention;

FIG. 3 is a schematic view illustrating a connection manner of a melting device and a guide tube according to an embodiment of the present invention;

FIG. 4 is a schematic view showing another alternative melt apparatus in connection with a conduit in accordance with an embodiment of the present invention;

fig. 5 is a schematic view illustrating a connection manner of a material melting device and a material guiding pipe according to another embodiment of the present invention.

The device comprises a feeding device 10, a raw material supply part 101, a feeding part 102, a vibrating feeder 103, a pulling driving part 104, a mass sensor 105, a pulling rope 106, a melting device 20, a material accommodating part 201, a first melting cavity 2011, a second melting cavity 2012, a heating part 202, a separating part 203, a heat preservation part 204, a material guide device 30, a material guide pipe 301, a heating part 302, a single crystal furnace 40, a crucible 401, a material stopping device 50, a driving part 501, a material stopping part 502 and a rod-shaped raw material 60.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood that these descriptions are illustrative only and are not intended to limit the scope of the present disclosure. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present disclosure.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.

Currently, processes for pulling single crystal silicon include CZ (Czochralski ) and CCZ (Continuous crystal pulling) processes.

When pulling a single crystal silicon rod by the CCZ process, a feeder apparatus is usually provided outside the single crystal furnace, and silicon material is continuously fed into a crucible of the single crystal furnace while pulling is maintained, thereby ensuring the progress of continuous pulling.

However, during the process of supplying the silicon material, when the solid silicon material directly falls into the melt in the crucible, large mechanical impact and thermal impact can be generated, the liquid level of the melt is oscillated, and the temperature gradient change is caused at the crystal growth interface, so that the growth of the single crystal is influenced.

Based on the technical problem, the embodiment of the invention discloses a single crystal furnace feeding system, which aims to solve the technical problem that in the process of supplying silicon materials, when the silicon materials fall into a melt in a crucible, large impact is generated, the liquid level of the melt is oscillated, and the growth of single crystals is influenced.

Referring to fig. 1, a charging system of a single crystal furnace provided by an embodiment of the invention comprises: a feeding device 10, a melting device 20 and a material guiding device 30.

Referring to fig. 1, a feeding device 10 is used for supplying raw material to a melting device 20, the melting device 20 is used for melting the supplied raw material to obtain molten material, and a guiding device 30 is connected to the melting device 20 and is used for guiding the molten material into a crucible of a single crystal furnace.

Specifically, the melting device 20 includes a first melting chamber 2011 and a second melting chamber 2012 communicated with each other. The feeding device 10 is connected to the first melting chamber 2011 for providing raw material to the first melting chamber 2011. After the raw material enters the first melt cavity 2011, the melting device 20 heats and melts the raw material to obtain a liquid melt. Because the first melt cavity 2011 is communicated with the second melt cavity 2012, the molten material obtained after the raw material is melted can enter the second melt cavity 2012 from the first melt cavity 2011.

The first melt cavity and the second melt cavity may have the same size or different sizes, and may be set according to actual requirements.

Referring to fig. 1, the second melt chamber 2012 is communicated with a feeding port of the material guiding device 30, and a discharging port of the material guiding device 30 extends into the single crystal furnace 40 for guiding the melt in the second melt chamber 2012 into the crucible 401 of the single crystal furnace 40.

In practice, the single crystal furnace can be provided with CCZ function by forming a hole in the side wall of the furnace platform of the single crystal furnace and connecting the feeding system of the single crystal furnace with the single crystal furnace through the hole.

Specifically, the melting device provided by the embodiment of the invention can be connected with the furnace platform of the single crystal furnace through a flange, and holes are formed in the side wall of the second melting cavity and the side wall of the crucible of the single crystal furnace, so that the material guide device can pass through the holes.

Based on this, the raw material is melted outside the single crystal furnace, and the melted liquid melt is added into the crucible of the single crystal furnace, so that when the liquid melt is added into the crucible, compared with the case of adding the solid raw material into the crucible, the impact on the melt existing in the crucible can be greatly reduced, and the ripple on the liquid level of the melt in the crucible can be hardly caused. Moreover, the molten raw materials are added into the crucible, so that the influence on the temperature gradient of a thermal field and convection in the crucible is small due to heat absorption caused by melting, and stable crystal pulling is facilitated.

The melting device in the charging system of the single crystal furnace provided by the embodiment of the invention comprises a first melting cavity and a second melting cavity which are communicated. The discharge port of the feeding device is communicated with the first melting cavity for supplying raw materials to the first melting cavity, and the second melting cavity is communicated with the feeding port of the material guiding device for supplying melting materials to the crucible of the single crystal furnace through the material guiding device. Therefore, when raw materials are added into the first melting cavity, the liquid level of the second melting cavity cannot generate ripples, so that the stability of melting materials flowing into the single crystal furnace is guaranteed, and the quality of the single crystal silicon rod is further guaranteed.

In practical applications, the raw material added to the melting device may be a solid raw material, wherein the solid raw material includes a block raw material and a rod raw material. For example, the chunk raw material may be a chunk polycrystalline silicon raw material, and the rod-shaped raw material may be a polycrystalline silicon rod.

In one possible implementation, referring to fig. 1, when the raw material added to the melting device is a solid raw material, the feeding device includes a feeding portion 102. The pan feeding mouth of feeding portion is used for receiving solid-state raw materials, and the discharge gate and the relative setting of first melt cavity of feeding portion for provide solid-state raw materials to first melt cavity. The discharge port of the feeding part is higher than the top height of the melting device, and the discharge port of the material guide device is higher than the top height of a crucible in the single crystal furnace.

Based on this, the discharge gate height of feeding portion is higher than the top height of melting device, and the discharge gate height of guide device is higher than the top height of crucible in the single crystal growing furnace. Based on this, solid raw materials in the feeding portion can utilize self gravity feeding portion to get into the guide device, and the melt in the guide device also can get into the crucible through self gravity, need not with the help of any power unit, also need not to make any special design to the structure of feeding portion and guide device.

The feeding device further comprises a raw material supply part 101 and a vibration feeder 103. The discharge port of the raw material supply portion 101 is opposite to the feeding end of the feeding portion 102, and is used for providing solid raw material to the feeding portion 102, and the discharge end of the feeding portion 102 is opposite to the first melt cavity 2011. The vibrating feeder 103 is connected to the feeding portion 102 for providing a vibrating force to the feeding portion 102 to make a predetermined mass of the solid raw material in the feeding portion 102 enter the melting device 20. The vibrating feeder 103 is also in communication with a controller of the melting device 20 for providing a vibrating parameter to the controller, and the controller is configured to control a heating parameter of the heating portion of the melting device 20 according to the vibrating parameter.

Specifically, referring to fig. 1, the raw material supplying portion 101 may have a funnel shape, and in this case, the raw material enters the raw material supplying portion 101 from an upper opening of the raw material supplying portion and leaks out from a bottom of the raw material supplying portion onto the charging portion 102.

Wherein, the charging portion 102 may be a groove-shaped charging portion. The feeding end of the feeding portion 102 is opposite to the bottom of the funnel-shaped raw material supplying portion 101, and the discharging end of the feeding portion 102 extends into the melting device and is opposite to the first melting cavity for feeding the solid raw material into the first melting cavity. A vibrating feeder 103 is provided at a lower side of the feeding portion 102. Preferably, a vibratory feeder 103 may be provided at the lower side of the feeding end of the feeding portion 102 for providing a vibratory force to the feeding portion 102 to feed the solid raw material into the first melt cavity.

The vibration parameters of the vibration feeder 103 can be adjusted, and the vibration force applied to the feeding part 102 can be adjusted by adjusting the vibration parameters of the vibration feeder 103, so that raw materials with preset mass in the feeding part can enter the melting device, and the controllability of the feeding system of the single crystal furnace is improved. The raw materials with the preset mass may be determined according to actual requirements, and this is not specifically limited in the embodiment of the present invention.

Further, the vibrating feeder 103 is also configured to send the vibration parameters of the vibrating feeder 103 to the controller of the melting apparatus 20 when the vibrating feeder 103 provides the vibrating force to the feeding portion 102. The controller controls the heating parameters of the heating portion of the melting device 20 according to the vibration parameters. Based on the heating parameters, the heating part can melt the raw materials added in the melting device within a proper time period so as to meet the actual requirement.

Based on the above, the heating parameters of the heating part in the melting device can be set according to the quality of the raw material added into the melting device, so that the raw material added into the melting device can be fully melted, and the quality of the pulled silicon single crystal rod can be further improved.

In one possible implementation, referring to fig. 2, when the raw material added to the melting device is a rod-shaped raw material, the feeding device includes a pulling driving part 104 and a mass sensor 105. The mass sensor 105 may be provided on the pulling head of the pulling driving part 104 or on the pulling rope 106 for pulling the rod-shaped raw material, and the specific installation position of the mass sensor 105 is not limited in the embodiment of the present invention as long as the real-time mass of the rod-shaped raw material can be obtained.

Referring to fig. 2, the mass sensor 105 is also communicatively connected to a controller of the melting device 20 for sending the current mass of the rod-shaped raw material to the controller for controlling heating parameters of the heating portion of the melting device 20 based on the current mass of the rod-shaped raw material.

Specifically, referring to fig. 2, the pulling driving portion 104 is located above the melting device, the pulling driving portion 104 is connected to a first end of the rod-shaped raw material, a second end of the rod-shaped raw material 60 extends into the first melting cavity 2011, and the pulling driving portion 104 is used for controlling the length of the rod-shaped raw material extending into the first melting cavity 2011. The mass sensor is used for acquiring the current mass of the rod-shaped raw material in real time during the melting process of the rod-shaped raw material and sending the current mass to the controller of the melting device 20, and the controller stores the mass of the rod-shaped raw material acquired by the mass sensor 105 at the previous moment. Accordingly, the controller may determine the heating parameters of the heating portion of the melting device 20 based on the current mass of the rod-shaped raw material and the previous-time mass of the rod-shaped raw material.

Based on the above, the heating parameters of the heating part in the melting device are set according to the quality of the raw material added into the melting device, so that the raw material added into the melting device can be fully melted, and the quality of the pulled monocrystalline silicon rod can be further improved.

Referring to fig. 1 or 2, the melting device 20 includes a material receiving portion 201, a heating portion 202, and a separating portion 203. The separating portion 203 is disposed in the material accommodating portion 201, and is configured to separate the material accommodating portion 201 into a first melt cavity 2011 and a second melt cavity 2012 which are communicated with each other.

Further, the melting device may further include a housing and a heat-insulating member 204, the material accommodating portion 201, the heating portion 202, and the separating portion 203 are all disposed in the housing, the heat-insulating member 204 is disposed on the periphery of the material accommodating portion 201, and the heat-insulating member 204 may be a heat-insulating felt for preventing heat dissipation of the material accommodating portion.

Based on this, because the melting device comprises the independent heating part, the melting device can control the heating part independently, thereby can control the melting process of the raw materials in the material containing part independently. For example, the melting device can control the heating part differently according to the quality of the raw materials added into the material containing part, thereby improving the controllability of the charging system of the single crystal furnace.

In practice, after the feeding device adds the raw material to the first melt cavity, the heating portion of the melt device heats the material accommodating portion to melt the raw material in the first melt cavity, so as to obtain the melt. Melt enters the second melt cavity through the first melt cavity. It will be appreciated that due to the presence of the partition, unmelted raw material does not enter the second melt chamber, and therefore, the melt flowing from the second melt chamber into the crucible of the single crystal furnace is liquid melt. So as to further ensure that the liquid level of the molten material in the crucible does not fluctuate during feeding, and ensure the quality of the pulled monocrystalline silicon rod.

In a preferred embodiment, the bottom of the first melting cavity is communicated with the bottom of the second melting cavity, and the feeding port of the material guiding device is not lower than the bottom of the partition part. Under the circumstances that the bottom of first cavity is linked together with the bottom of second melt cavity, the melt can flow between first melt cavity and second melt cavity, and can guarantee that first melt cavity and second melt cavity liquid level are flat mutually. On the basis, the feeding port of the material guide device is not lower than the bottom of the separating part, and the separating part limits the solid raw material in the first melt cavity, so that the solid raw material does not exist in the melt entering the crucible of the single crystal furnace, the melt liquid level in the crucible is further ensured not to fluctuate during feeding, and the quality of the pulled single crystal silicon rod is ensured.

In a specific implementation manner, the partition portion 203 may be fixed on the inner wall of the material containing portion 201 by welding. The partition 203 may be a partition welded to the inner wall of the receiving portion. The material containing part 201 may be a crucible disposed in a housing of the melting furnace, and the heating part 202 is disposed at an outer periphery of the crucible, or disposed at an outer periphery and both sides of the crucible, for heating the raw material in the crucible to melt the raw material in the crucible to obtain the molten material.

The heating part 202 may be a graphite heater, for example.

As a specific example, a graphite heater is arranged on the periphery of a crucible in a melting furnace, raw material in the melting furnace is heated by the graphite heater, liquefied and finally enters the crucible of a single crystal furnace through a material guiding device for single crystal pulling. The crucible is divided into a left part and a right part by a partition plate in the melting furnace to form a left liquid surface and a right liquid surface, so that the liquid surface on the other side can not generate ripples when the blocky source materials are added. Wherein, the baffle is a high-strength high-heat-resistance nonmetal baffle.

The material guiding device can comprise a material guiding part and a heating part arranged on the material guiding part. Wherein, the material guiding piece can be a material guiding pipe. The material of the material guide pipe can be non-metal high-purity material.

Specifically, referring to fig. 1 or fig. 2, a first end of the guide tube 301 is communicated with the second melt chamber 2012, and a second end of the guide tube extends into the single crystal furnace 40, so that the melt in the second melt chamber 2012 can enter the crucible 401 of the single crystal furnace 40 through the guide tube 301.

The heating member 302 is disposed at the periphery of the material guiding pipe 301, and is electrically connected to an external power source, so as to heat the circulating molten material in the material guiding pipe 301, so as to ensure that the circulating molten material in the material guiding pipe 301 is not crystallized, thereby ensuring that the molten material in the material guiding pipe has stable fluidity.

The heating member may be an electromagnetic induction heating member. Specifically, the electromagnetic induction heating member is an electromagnetic heating coil. The electromagnetic heating coil may be a high or medium frequency coil.

This electromagnetic heating coil encircles in the periphery of passage to carry out even heating to the melt in the passage, based on this, can the omnidirectional heat the melt in the passage, take place the crystallization with the melt of avoiding any region in the passage.

Furthermore, in order to ensure that the solid raw material in the first melting cavity cannot enter the material guide pipe, the first end of the material guide pipe is not lower than the bottom of the partition part.

For example, referring to fig. 3, the first end of the guide tube 301 is oppositely disposed at the top of the partition 203.

For another example, referring to fig. 4, the first end of the guide tube 301 is oppositely disposed at the middle of the partition 203.

For another example, referring to fig. 5, the first end of the guide tube 301 is oppositely disposed at the bottom of the partition 203.

Preferably, a feeding port of the material guiding device is communicated with the top of the second melt cavity, that is, the material guiding pipe 301 is communicated with the top of the second melt cavity. Based on this, the melt can overflow to the pan feeding mouth of passage through the top of second melt cavity, and then gets into in the crucible in the single crystal growing furnace. The solid raw material is located at the bottom of the melting device because the raw material entering the melting device is solid raw material, which is denser than the molten material. In the invention, the molten material overflows from the top of the second molten material cavity to the material inlet of the material guide device, so that solid raw materials can be further prevented from entering the material guide device.

Furthermore, the charging system of the single crystal furnace provided by the embodiment of the invention further comprises a material blocking device, wherein the material blocking device is arranged at a material inlet of the material guiding device and is used for adjusting the flow speed and flow of the molten material flowing into the material guiding device. The material blocking device comprises a material blocking end, and the material blocking end is arranged at a material inlet of the material guiding device.

Referring to fig. 1, the material blocking device 50 includes a material blocking member 502 and a driving member 501 in driving connection with the material blocking member 502. One end of the material blocking member 502 is in driving connection with the driving member 501, and the other end is disposed at the material inlet of the material guiding device 30, so as to adjust the area of the material inlet blocking the material guiding device 30 under the driving of the driving member 501.

The material blocking part 502 can be a material blocking plate, the driving part 501 can be a gate valve, and the gate valve is in driving connection with an external motor and is also connected with the material blocking plate. In a specific control process, the opening and closing degree of the gate valve is controlled by using an external motor, so that the position of the material blocking end of the material blocking plate at the material inlet is controlled, and the area of the material inlet of the material guiding device, which is blocked by the material blocking part, is adjusted.

In practice, the baffle plate can be controlled to shield the area of a feeding hole of the material guide device according to the requirement of the single crystal furnace so as to control the flow speed and flow of the molten material circulating in the material guide device, and the stability of the liquid level of the molten material in a crucible of the single crystal furnace can be further controlled.

The embodiment of the invention also provides a feeding control method, which comprises the following steps:

controlling a feeding device to provide raw materials to the first melting cavity;

controlling the melting device to melt the raw materials to obtain a molten material; and the molten materials enter the single crystal furnace through the material guide device.

The beneficial effects of the feeding control method provided by the embodiment of the invention are the same as those of the single crystal furnace feeding system, and are not described again here.

While the invention has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

While the invention has been described in conjunction with specific features and embodiments thereof, it will be evident that various modifications and combinations can be made thereto without departing from the spirit and scope of the invention. Accordingly, the specification and figures are merely exemplary of the invention as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (15)

1. The single crystal furnace charging system is characterized by comprising a charging device, a melting device and a material guiding device; the melting device comprises a first melting cavity and a second melting cavity which are communicated with each other;

a discharge port of the feeding device is communicated with the first melt cavity and is used for providing raw materials for the first melt cavity; the melting device is used for melting the raw materials to obtain a molten material;

the second melt cavity is communicated with a feeding port of the material guide device, a discharging port of the material guide device extends into the single crystal furnace, and the melt in the second melt cavity enters a crucible of the single crystal furnace through the material guide device.

2. The charging system of the single crystal furnace according to claim 1, wherein the melting device comprises a material containing part, a heating part and a separating part; the heating part is used for heating the material containing part, and the separating part is arranged in the material containing part and used for separating the material containing part into the first molten material cavity and the second molten material cavity.

3. The charging system of the single crystal furnace as claimed in claim 2, wherein the bottom of the first melt chamber is connected to the bottom of the second melt chamber, and the inlet of the guiding device is not lower than the bottom of the partition.

4. The charging system of a single crystal furnace according to claim 2, wherein the material guiding device comprises a material guiding member and a heating member disposed on the material guiding member;

and the first end of the material guiding piece is communicated with the second melting material cavity, the second end of the material guiding piece extends into the single crystal furnace, and the first end of the material guiding piece is not lower than the bottom of the separating part.

5. The charging system for a single crystal furnace according to claim 4, wherein the heating member is an electromagnetic induction heating member;

or, the heating member is an electromagnetic induction heating coil, the material guiding member is a material guiding pipe, and the heating coil is arranged around the periphery of the material guiding pipe.

6. The charging system of the single crystal furnace as claimed in any one of claims 1 to 5, wherein a feeding port of the material guiding device is communicated with the top of the second melt chamber.

7. The charging system of the single crystal furnace as claimed in any one of claims 1 to 5, further comprising a material blocking device arranged at the feed inlet of the material guiding device for adjusting the flow rate and flow rate of the molten material flowing into the material guiding device.

8. The charging system of the single crystal furnace as claimed in claim 6, wherein the material blocking device comprises a material blocking member and a driving member in driving connection with the material blocking member;

the material blocking part is arranged at the material inlet of the material guiding device and used for adjusting the area of the material inlet of the material guiding device under the driving of the driving part.

9. The charging system of the single crystal furnace as claimed in any one of claims 1 to 5, wherein the charging device supplies the raw material to the first melt chamber to comprise a solid raw material, and the charging device comprises a charging portion;

the feeding port of the feeding part is used for receiving the solid raw material, and the discharge port of the feeding part is arranged opposite to the first melt cavity and used for providing the solid raw material for the first melt cavity;

the discharge port of the feeding part is higher than the top of the melting device, and the discharge port of the material guide device is higher than the top of the crucible in the single crystal furnace.

10. The single crystal furnace charging system of claim 9, wherein the charging device further comprises a raw material supply portion and a vibrating feeder;

the discharge port of the raw material supply part is arranged opposite to the feeding end of the feeding part and is used for supplying the solid raw material to the feeding part, and the discharge end of the feeding part is arranged opposite to the first melting cavity;

the vibration feeder is connected with the feeding part and used for providing vibration force to the feeding part so that the solid raw materials with preset mass in the feeding part enter the melt device.

11. The single crystal furnace charging system of claim 10, wherein the vibrating feeder is further communicatively coupled to a controller of the melt assembly for providing a vibrating parameter to the controller, the controller being configured to control a heating parameter of a heating portion of the melt assembly based on the vibrating parameter.

12. The single crystal furnace charging system of claim 10, wherein the vibrating feeder is disposed at an end of the charging portion distal from the melt means.

13. The single crystal furnace charging system according to any one of claims 1 to 5, wherein the raw material comprises a rod-shaped raw material, and the charging device comprises a pulling driving part;

the pulling driving part is positioned above the melting device and is connected with the first end of the rod-shaped raw material, the second end of the rod-shaped raw material extends into the melting device, and the pulling driving part is used for controlling the length of the rod-shaped raw material extending into the melting device.

14. The single crystal furnace charging system of claim 13, wherein the charging device further comprises a mass sensor;

the quality sensor is used for acquiring the current quality of the rod-shaped raw material connected with the lifting driving part in real time;

the mass sensor is also in communication with a controller of the melting device and is configured to send the current mass of the rod-shaped raw material to the controller, and the controller is configured to control heating parameters of a heating portion of the melting device according to the current mass of the rod-shaped raw material.

15. A charging control method, which is applied to the charging system of the single crystal furnace of any one of claims 1 to 14, and which comprises:

controlling a feeding device to provide raw materials to the first melting cavity;

controlling the melting device to melt the raw materials to obtain a molten material; and the molten materials enter the single crystal furnace through the material guide device.

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