JP2013505891A - Polycrystalline silicon ingot manufacturing equipment equipped with a rotary door opening and closing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the thermal imbalance in the polycrystalline silicon growth space, to solve the problems due to the size restriction in the height direction of the ingot device corresponding to the future technical prospect, and to reduce the size of the door An apparatus for producing a polycrystalline silicon ingot that can be easily provided is provided.
A vacuum chamber having a predetermined size, a crucible provided in the vacuum chamber and containing a silicon raw material, a heater for applying heat to melt the silicon raw material in the crucible, and the crucible A susceptor provided on the lower side, a cooling plate for releasing heat to grow a molten silicon crystal in the crucible, a door opening / closing device provided between the crucible and the cooling plate to restrain heat dissipation, and the crucible A polycrystalline silicon ingot manufacturing apparatus including a temperature sensor for measuring temperature and a control unit for controlling the temperature in the crucible receiving the output value of the temperature sensor, wherein the door opening and closing device is spaced at a predetermined interval. It includes a first door and a second door formed with an opening, and includes a drive unit that selectively opens and closes the opening by the relative rotation of the first door and the second door. .
[Selection] Figure 4

Description

  The present invention relates to a polycrystalline silicon ingot manufacturing apparatus, and more specifically, a polycrystalline silicon ingot having a rotary door opening / closing device that can supplement the door opening / closing device and achieve effective silicon growth by improving thermal balance. It relates to a manufacturing apparatus.

  In recent years, solar power generation using silicon-type solar cells has reached a commercial stage through a trial stage due to advantages such as pollution-free, safety, and reliability.

  In the case of the United States, Japan, and Germany, solar power generation with a capacity of several hundred to several thousand Kw is performed using silicon solar cells. Currently, solar cells used for photovoltaic power generation are manufactured using a single crystal silicon thin plate mainly manufactured by the Czochralski pulling method. It is recognized that the price of sheet metal must be reduced to further increase productivity. Against this background, a casting method was developed as part of efforts to reduce the cost of solar silicon sheets.

  The production of a polycrystalline silicon ingot for solar cells by a casting method is basically characterized by directional solidification. After melting and melting polycrystalline silicon particles in a crucible made of quartz or graphite, the heat of dissolution of silicon is removed from the lower side of the crucible, so that cooling solidification moves from the lower side to the upper side of the crucible By doing so, an ingot of a so-called columnar structure having a certain direction is obtained.

  The polycrystalline silicon ingot produced in this way has a higher electrical efficiency in the production of solar cells due to the grain boundaries present inside than the single crystal silicon ingot produced by the pulling method. However, since the crystals are formed in a columnar shape with respect to the growth direction of the ingot, the overall physical properties are inferior by about 20% compared to the single crystal ingot. However, mass production (2 to 3 times that of the single crystal pulling method) is possible, and it has the advantages of excellent productivity (2 to 3 times that of the single crystal pulling method) and simple manufacturing technology. In terms of surface, it is about 1/2 to 1/3 of the level of the single crystal silicon ingot. The casting method known so far is a polycrystalline silicon melting part made of quartz. After the polycrystalline silicon is melted in advance before being supplied to the graphite crucible, the lower part to the upper part are maintained at 600 to 1,200 ° C. There is a method of producing a polycrystalline silicon ingot by supplying a square or round graphite crucible to cause crystal growth.

  However, in the conventional casting method, since the cold crucible rapidly cools and solidifies, it is possible to prevent adhesion between the solidified silicon and the crucible. There is a problem that the soot concentration becomes high and crystal grains become small.

  In order to solve such problems, the present applicant has applied for Patent Document 1 (name of invention: polycrystalline silicon ingot manufacturing apparatus for solar cells), and a cooling plate for heat dissipation in silicon growth. In order to solve the problem of the door opening and closing method in the approach method, various Korean applications were filed.

  There are various methods in the past, but among these methods, the crucible containing the molten liquid is lowered and moved away from the heater to cool the lower part. The method of drawing heat forcibly through a cold plate is universal. The crucible lowering method is preferred because it has a limit in discharging heat to the lower part, but this method is preferred, but this method releases heat to the lower heat exchanger when the silicon is melted. Insufficient phenomenon may occur, and thus energy consumption is greatly generated in the melting stage.

  For this reason, a device using a heat exchanger has a kind of gate in which a heat insulating material is mounted between the lower portions of the heat exchanger and the crucible. Since this gate is closed when the silicon melts, the heat released to the heat exchanger is shut off so that it melts smoothly, and when the crystal grows it is opened and sufficient heat is released to the heat exchanger below the gate. So that

  1 to 3 are related to the prior art filed by the present applicant, and constitute a gate (door opening / closing device) in an ingot manufacturing apparatus including a vacuum chamber 10, a heater 20, a crucible 30, a temperature sensor 40 and a gate 40. I proposed various ways to do it. There are two methods commonly used: a horizontal slide method shown in FIG. 1 and a method of controlling the opening and closing by pushing up the gate while the heat exchanger is raised by the hinge structure shown in FIG. The horizontal sliding method is disadvantageous for the uniform growth of the ingot because it causes a thermal imbalance in the growth space of the equipment. This is not preferable because it is the structure that affects the most important ingot growth. The door method with a hinge structure has the advantage that a symmetrical thermal equilibrium condition can be obtained, but the heat exchanger pushes the door up, so that the heat exchanger can sufficiently open and close the gate. Space is needed in the direction.

  In order to increase the size of the ingot in the future, it is necessary to grow the ingot not in the height direction but in the width direction. Since the height of the equipment will also increase together, there is a problem that has a disadvantageous structure to increase the size of the ingot.

Korean Patent Application No. 10-2007-0006218

  In order to solve the above-mentioned problems, the present invention eliminates the thermal imbalance in the polycrystalline silicon growth space, and the size of the ingot apparatus in the height direction in response to future technical prospects. The object is to provide an apparatus for producing a polycrystalline silicon ingot capable of solving the problems caused by the restrictions and facilitating the size of the door.

  To achieve the above object, the present invention provides a vacuum chamber having a predetermined size, a crucible provided in the vacuum chamber and containing a silicon raw material, and melting the silicon raw material in the crucible. A heater for applying heat, a susceptor provided below the crucible, a cooling plate for releasing heat to grow molten silicon crystals in the crucible, and between the crucible and the cooling plate. A polycrystalline silicon ingot manufacturing apparatus, comprising: a door opening and closing device that restrains the temperature; a temperature sensor that measures the temperature of the crucible; and a control unit that controls the temperature in the crucible receiving the output value of the temperature sensor. The door opening and closing device includes a first door and a second door formed with an opening at a predetermined interval, and the opening is selected by relative rotation of the first door and the second door. Comprising a drive unit for opening and closing, provides a polycrystalline silicon ingot production apparatus provided with a rotary door openers.

  The driving unit may include a first driving motor and a second driving motor that rotate the first door and the second door, respectively.

  The first door and the second door are coupled to and rotated by a first hollow shaft and a second hollow shaft connected to the first drive motor and the second drive motor, respectively, and the second hollow shaft is a first hollow shaft. The first hollow shaft may be further provided with a support shaft that supports the lower portion of the susceptor.

  The support shaft is formed by extending the first hollow shaft, and may further include a bearing at a portion in contact with the susceptor.

  The support shaft may be separately provided, and a bearing may be further provided at a portion in contact with the first hollow shaft.

  The support shaft may penetrate the hollow of the first hollow shaft and be separately fixed to the outside.

  The drive unit includes transfer means including a shaft for transferring the first door up and down; a drive motor for rotating the second door; and a first door for interlocking the first door by rotation of the second door The second doors may include locking portions that are respectively provided and locked to each other.

  The shaft is inserted into the hollow of a hollow support shaft provided for supporting the susceptor, and a plate is provided at an end of the shaft for moving the first door up and down by the transfer means, the plate Is coupled to a coupling hole formed in the hollow support shaft, and the first door can be transported by vertical transport.

  The driving unit may further include an encoder for detecting a rotation amount of the first door and the second door.

  The first door and the second door can be controlled to adjust the amount of heat absorption by adjusting the degree of opening of the opening by an arbitrary angle.

  In order to achieve the above-described object, the present invention provides a cooling plate by selectively opening a door opening / closing device after melting a silicon raw material with a crucible provided in a vacuum chamber of a predetermined size. A polycrystalline silicon ingot manufacturing apparatus for growing crystals of a silicon raw material melted by exposing, wherein the door opening / closing device includes a first door and a second door having an opening formed at a predetermined interval. A polycrystalline silicon ingot manufacturing apparatus having a rotary door opening and closing device is provided, which includes a drive unit that selectively opens and closes an opening portion by relative rotation of the first door and the second door.

  The present invention configured and operated as described above has an advantage that the thermal imbalance can be eliminated and the defects of silicon growth can be eliminated.

  Also, the structural features of the switchgear can reduce the overall size of the ingot manufacturing device and increase the size of the door, so that effective silicon solidification can be achieved as a result. There are advantages.

It is a general | schematic incision perspective view of the ingot manufacturing apparatus for solar cells by a prior art. It is a general | schematic incision perspective view of the ingot manufacturing apparatus for solar cells by a prior art. It is a general | schematic incision perspective view of the ingot manufacturing apparatus for solar cells by a prior art. It is a perspective view which shows the state before opening of the rotary door opening and closing apparatus by this invention. It is a state figure showing the state after opening of the rotation type door opening and closing device by the present invention. It is sectional drawing which shows one Example of the drive means for the rotary door opening and closing by this invention. It is sectional drawing which shows the other Example of the drive means for the rotation type door opening and closing by this invention. It is sectional drawing which shows the other Example of FIG. FIG. 10 is a cross-sectional view showing still another embodiment of FIG. 7. It is sectional drawing which shows the further another Example of the drive means for the rotation type door opening and closing by this invention. It is sectional drawing which shows the operation state of FIG. 1 is a cut perspective view of a polycrystalline silicon ingot manufacturing apparatus provided with a rotary door opening and closing device according to the present invention.

  Hereinafter, a preferred embodiment of a polycrystalline silicon ingot manufacturing apparatus equipped with a rotary door opening and closing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  4 is a perspective view showing a state before opening of the rotary door opening and closing device according to the present invention, FIG. 5 is a state diagram showing a state after opening of the rotary door opening and closing device according to the present invention, and FIG. 6 is a rotation type according to the present invention. FIG. 7 is a sectional view showing another embodiment of the driving means for opening and closing the rotary door according to the present invention.

  8 is a cross-sectional view showing another embodiment of FIG. 7, FIG. 9 is a cross-sectional view showing still another embodiment of FIG. 7, and FIG. 10 is a drive means for opening and closing a rotary door according to the present invention. 11 is a cross-sectional view showing another embodiment, FIG. 11 is a cross-sectional view showing the operating state of FIG. 10, and FIG. 12 is a cut-out perspective view of a polycrystalline silicon ingot manufacturing apparatus equipped with a rotary door opening and closing device according to the present invention.

  The polycrystalline silicon ingot manufacturing apparatus including the rotary door opening and closing apparatus 500 according to the present invention includes a vacuum chamber 100 having a predetermined size, a crucible 200 provided in the vacuum chamber and containing a silicon raw material, and the crucible. A heater 220 for applying heat to melt the silicon raw material therein, a susceptor 210 provided under the crucible, and a cooling plate 400 for releasing heat to grow molten silicon in the crucible; A door opening / closing device 500 provided between the crucible and the cooling plate, which restrains heat dissipation in order to melt or grow silicon; a temperature sensor 300 for measuring the temperature of the crucible; and an output value of the temperature sensor. And a controller for controlling the temperature in the crucible so that the silicon melts and grows uniformly. In the crystal silicon ingot manufacturing apparatus, the door opening / closing device includes a first door 510 and a second door 520 formed with a circular structure at predetermined intervals, and a relative relationship between the first door and the second door. The driving unit 540 selectively opens and closes the opening by rotation.

  A predetermined space is formed inside the vacuum chamber 100, and most of the components of the ingot manufacturing apparatus are provided in the vacuum chamber 100.

  The crucible 200 is for containing a silicon raw material and melting it inside, and is preferably provided at the center of the vacuum chamber 100. The crucible 200 has a shape in which an upper part is opened, and a cover (not shown) for opening and closing the upper part may be provided separately. The crucible 200 is preferably formed in the shape of a regular hexahedron, as shown in the drawings, and is made of quartz.

  Meanwhile, a susceptor 210 is provided below the crucible 200. This susceptor serves to protect the crucible 200. The material of the susceptor is preferably made of carbon or graphite having excellent heat transfer characteristics.

  A heater 220 is provided around the crucible except for the lower side of the crucible provided with the susceptor 210. Of course, a heater may be provided in the lower part of the susceptor 210. However, in one embodiment of the present invention, the heater 220 is provided only on and around the susceptor 210. This is because the silicon raw material in the crucible 200 can be melted by providing the heater 220 only on and around the susceptor 210.

  As described above, the heater is for melting the silicon raw material in the crucible, and the melting point of the silicon raw material is about 1,423 ° C. As an example, the heater power control method can be operated by a method of controlling the duty ratio of the voltage pulse applied to the heater or a method of controlling the cycle of the voltage pulse applied to the heater.

  Of course, such temperature measurement is performed by the temperature sensor 300. A large number of the temperature sensors can be provided in the ingot production apparatus. As a preferred example, the temperature sensor is installed in the heater crucible to measure the temperature.

  Meanwhile, a cooling plate 400 for growing molten silicon is provided below the susceptor provided below the crucible, and a door opening / closing device 500 is provided between the cooling plate and the susceptor. That is, the molten silicon in the crucible grows by the cooling plate 400 when the door of the door opening / closing device is opened.

  As an example, the cooling plate 400 has a refrigerant passage formed on the inner side, and the cooling plate cooled by moving the refrigerant along the refrigerant passage releases heat of the crucible.

  Since the schematic configuration of the polycrystalline silicon ingot manufacturing apparatus configured as described above is described in detail in Patent Document 1 (polycrystalline silicon ingot manufacturing apparatus for solar cells) filed by the present applicant, The specific description is omitted.

  The door opening / closing device 500 is a main technical gist according to the present invention, in which a first door 510 and a second door 520 each having an opening formed at regular intervals are arranged vertically, and the opening is opened by rotating the door. Heat release for silicon growth (solidification) is performed by exposing the cooling plate 400 provided on the lower side of the door opening / closing device directly to the crucible by opening it by a certain angle.

  Hereinafter, the door opening and closing apparatus 500 according to the present invention will be described in more detail.

  The first door 510 and the second door 520 have a radial structure, and open portions are formed radially in a circular or polygonal structure. In such a structure, the first door and the second door are equally provided, and the opening portions of the first door and the second door are made to coincide with each other by rotation or are made to coincide with each other at a specific angle, and then simultaneously rotated. Perform heat dissipation. Here, the determination of the degree of opening only for a specific angle of the opening is for adjusting the amount of heat absorption appropriately.

  Also, various embodiments of the driving unit 540 for driving the first door and the second door will be described.

  FIG. 6 shows a structure of a driving unit 540 according to an embodiment of the door opening and closing apparatus 500 according to the present invention, which includes a first driving motor 541 for driving the first door and a second driving motor 542 for driving the second door. With. Here, each door and the driving motor transmit driving force through the hollow first hollow shaft and the second hollow shaft.

  As shown, the first hollow shaft is connected to the first door, and the second hollow shaft is connected to the second door. At this time, the first hollow shaft has a structure inserted into the hollow of the second hollow shaft, and a component such as a bearing (not shown) may be disposed between the first hollow shaft and the first hollow shaft for smooth rotation. it can. Furthermore, it is preferable that a bearing is installed outside the second hollow shaft for smooth rotation.

  In this case, the connection structure of the drive motor will be described. The first drive motor 541 is directly connected to the first hollow shaft 511 according to the structural characteristics of the first hollow shaft inserted into the second hollow shaft. The second drive motor 542 transmits drive force from one side to the second hollow shaft 521 using power transmission means such as a drive belt or a chain belt. Such a mechanism of the driving unit can be easily changed by a person skilled in the art.

  Explaining the operation principle of the door opening / closing device configured as described above, when melting the silicon raw material in the crucible, the melting is performed while the open portions of the first door and the second door are shifted (closed state). In order to grow molten silicon into polycrystal, the first door or the second door is rotated by the operation of the driving unit, and the opening unit is rotated by a certain amount so as to have a specific opening degree.

  Then, the silicon grows by performing heat radiation by the cooling plate 400 provided under the door opening and closing device. Also, if the opening of the first door and the second door coincide with each other and silicon growth begins, the thermal equilibrium state on the lower side of the crucible can be achieved by growing the first door and the second door while rotating simultaneously. Cool gradually from below while maintaining.

  Meanwhile, the first and second driving motors may further include a rotational position detecting unit such as an encoder 560. The encoder is provided to detect the amount of rotation for adjusting the opening angle between the doors or to detect and control an appropriate amount of rotation from the total rotation of the door.

  FIG. 7 shows a structure for supporting a susceptor 210 provided on a lower side of a crucible using a structure of a driving unit according to another embodiment of the present invention. Since the center of the susceptor is subjected to the highest load, sagging can occur. Accordingly, a support shaft 530 extending to the first hollow shaft is further provided to support the center of the susceptor. Here, the support shaft 530 includes a bearing 512 at the end in contact with the susceptor, so that when the first hollow shaft rotates, the support shaft 530 rotates smoothly without friction by the bearing.

  As another embodiment, the one shown in FIG. 8 includes a support shaft 530. This is configured by dividing from the first hollow shaft, one end in contact with the susceptor is fixed to the susceptor, and the other end of the support shaft is in contact with the rotating first hollow shaft. This is a structure in which a bearing is installed.

  FIG. 9 shows still another embodiment of the present invention, in which the above-described support shaft is not provided on the first hollow axis, but is provided separately, and penetrates through the hollow interior of the first hollow shaft. It has a structure that supports

  One end of the support shaft supports the susceptor, penetrates the hollow of the first hollow shaft, and the other end is supported by an external structure. At this time, a bearing may be provided between the first hollow shaft and the support shaft for smooth rotation and support.

  10 and 11 show another embodiment of the drive unit according to the present invention, which has a structure in which a drive motor and a cylinder are used to drive two doors by the operation of the cylinder and the drive motor. A method of driving is proposed.

  First, as mentioned above, the first hollow shaft and the second hollow shaft are provided. The first hollow shaft is not connected to the first door but extends to support the susceptor. A shaft connected to a cylinder and moving up and down passes through the hollow interior of the first hollow shaft, and a plate 552 for supporting the first door and moving it up and down is provided at an end of the shaft. At this time, coupling holes 531 are provided on both sides of the first hollow shaft corresponding to the position of the plate, and the plate projects outward through the coupling hole.

  The second hollow shaft is connected to the second door and has the same role for rotating the second door, as in the embodiment described above.

  On the other hand, the first and second doors are each provided with a locking portion 522 so that the first door can be interlocked by the rotation of the second door. The locking portion is provided so that when the first door is fixed to the second door, the locking portions are locked to each other, and the first door rotates together with the rotation of the second door.

  Explaining the operation principle of the locking part, when the heat is required for silicon growth with the door closed, the cylinder is operated upward and the plate connected to the shaft is the first door. Push up. With the first door pushed up, the first drive motor rotates the second door by a certain angle, so that the locking portions of the first door and the second door are locked with each other. It becomes a preparation state which can pinpoint the position of 2 doors. Thereafter, if the second door is rotated in the opposite direction by a desired angle, the opening and closing angles of the first door and the second door are specified to a desired degree.

  After that, the plate supporting the first door places the first door on the second door by driving the cylinder downward. In this way, with the first door placed on the second door, the first door is restrained by the rotation of the second door, and the opening angle of the door maintains the counterpart angle with the specific second door. It starts to rotate.

  The door is closed by moving the first door upward from the second door by the cylinder, releasing it, rotating the second door by a predetermined angle and rotating it in the reverse direction by the opening angle, and then further opening the first door. The opening of the opening is released by moving the button downward.

  The present invention configured as described above has an advantage in that the rotational imbalance can be eliminated by applying the rotary door opening and closing device, thereby eliminating the disadvantages of silicon growth. This has the effect of reducing the overall size of the ingot manufacturing apparatus.

  While the present invention has been described with reference to the preferred embodiments for illustrating the principle of the present invention, the present invention is not limited to the configurations and operations described with reference to the drawings.

  Rather, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the appended claims. Accordingly, all such appropriate changes and modifications and equivalents shall be deemed to be within the scope of the present invention.

  The present invention can be applied to a polycrystalline silicon ingot manufacturing apparatus having a rotary door opening / closing device that can supplement the door opening / closing device and achieve effective silicon growth by improving the thermal balance.

DESCRIPTION OF SYMBOLS 100 Vacuum chamber 200 Crucible 210 Susceptor 220 Heater 300 Temperature sensor 400 Cooling plate 500 Door opening / closing device 510 1st door 511 1st hollow shaft 512 Bearing 513 Locking part 520 2nd door 521 2nd hollow shaft 522 Locking part 530 Support shaft 531 Coupling hole 540 Drive unit 541 First drive motor 542 Second drive motor
550 Transfer means 551 Shaft 552 Plate 560 Encoder

Claims (11)

A vacuum chamber of a predetermined size, a crucible provided in the vacuum chamber and containing a silicon raw material, a heater for applying heat to melt the silicon raw material in the crucible, and a lower side of the crucible A susceptor, a cooling plate for releasing heat to grow a silicon crystal melted in the crucible, a door opening / closing device provided between the crucible and the cooling plate to restrain heat dissipation, and a temperature of the crucible In a polycrystalline silicon ingot manufacturing apparatus including a temperature sensor and a control unit that controls the temperature in the crucible receiving the output value of the temperature sensor,
The door opening and closing device includes a first door and a second door having an opening formed at a predetermined interval,
An apparatus for producing a polycrystalline silicon ingot having a rotary door opening and closing device, comprising: a driving portion that selectively opens and closes an opening portion by relative rotation of the first door and the second door.   2. The rotary door opening and closing apparatus according to claim 1, wherein the driving unit includes a first driving motor and a second driving motor that rotate the first door and the second door, respectively. Polycrystalline silicon ingot production equipment. The first door and the second door are coupled to a first hollow shaft and a second hollow shaft connected to the first drive motor and the second drive motor, respectively, and rotate.
The second hollow shaft is inserted into the hollow of the first hollow shaft;
The apparatus for producing a polycrystalline silicon ingot according to claim 2, wherein the first hollow shaft further includes a support shaft for supporting a lower portion of the susceptor.   The multiple support door opening and closing device according to claim 3, wherein the support shaft is formed by extending the first hollow shaft, and further includes a bearing at a portion in contact with the susceptor. Crystal silicon ingot manufacturing equipment.   The apparatus for producing a polycrystalline silicon ingot according to claim 3, wherein the support shaft is provided separately, and a bearing is further provided at a portion in contact with the first hollow shaft.   The apparatus for producing a polycrystalline silicon ingot according to claim 3, wherein the support shaft penetrates through the hollow of the first hollow shaft and is separately fixed to the outside. The drive unit is
Transfer means including a shaft for moving the first door up and down;
A driving motor that rotates the second door; and a locking portion that is provided on each of the first door and the second door to be interlocked with each other in order to interlock the first door by the rotation of the second door. A polycrystalline silicon ingot manufacturing apparatus comprising the rotary door opening and closing device according to claim 1.   The shaft is inserted into the hollow of a hollow support shaft provided for supporting the susceptor, and a plate is provided at an end of the shaft for moving the first door up and down by the transfer means, the plate The polycrystalline silicon casting having a rotary door opening and closing device according to claim 7, wherein the first door is transported by being vertically moved and coupled to a coupling hole formed in the hollow support shaft. Lump production equipment.   The polycrystalline silicon ingot having a rotary door opening and closing device according to claim 1, wherein the driving unit further comprises an encoder for detecting a rotation amount of the first door and the second door. manufacturing device.   The said 1st door and a 2nd door are controlled so that the amount of heat absorption may be adjusted by adjusting the open degree of an open part only by arbitrary angles, It is characterized by the above-mentioned. Polycrystalline silicon ingot manufacturing device equipped with a rotary door opening and closing device. After melting the silicon raw material with a crucible provided in a vacuum chamber of a predetermined size, the silicon is grown by exposing the cooling plate by selectively opening the door opening and closing device. In the ingot production equipment,
The door opening and closing device includes a first door and a second door having an opening formed at a predetermined interval,
An apparatus for producing a polycrystalline silicon ingot having a rotary door opening and closing device, comprising: a driving portion that selectively opens and closes an opening portion by relative rotation of the first door and the second door.