JP4153540B2 - Board manufacturing equipment - Google Patents

Description

  The present invention relates to a substrate manufacturing apparatus for manufacturing a thin plate-shaped substrate from a metal or semiconductor melt.

  As a method for manufacturing a thin plate substrate, a crystal ribbon method and an EFG (Edge-defined Film-fed Growth) method are known. A substrate manufacturing apparatus that realizes these methods has an advantage that the apparatus is downsized because the drive unit is provided outside the chamber in which crystal growth is performed (see, for example, Patent Document 1). However, these methods do not perform crystal growth in the thickness direction of the substrate, but manufacture the substrate by crystal growth in a direction perpendicular to the thickness direction of the substrate, so that there is a problem that the productivity of the substrate is low. is there.

  FIG. 9 is a cross-sectional view showing another conventional substrate manufacturing apparatus 101. The substrate manufacturing apparatus 101 manufactures a substrate by immersing a plate-like cooling body 103 in a melt 102 of a substrate material, and crystal-growing the melt 102 on the surface 103 a in the thickness direction of the cooling body 103. This increases the productivity of the substrate.

  The substrate manufacturing apparatus 101 includes a crucible 111 that accommodates the melt 102, a transport means 104 that holds the cooling body 103 and is immersed in the melt 102, a chamber 105 that houses the crucible 111 and the transport means 104, and a load lock chamber 106, a gate valve 107, and a vacuum pump 108. In FIG. 9, the moving direction of the conveying means 104 is indicated by an arrow 109.

  The load lock chamber 106 includes a load lock chamber 106a for carrying in when the cooling body 103 is carried into the chamber 105, and a cooling body 103 when carrying out the cooling body 103 from the chamber 105 to the outside of the substrate manufacturing apparatus 101. And a load lock chamber 106b for carrying out. The loading and unloading load lock chambers 106 are each separated from the chamber 106 by a gate valve 107 and shielded from the outside air. The gate valve 107 is opened only when the cooling body 103 passes. The inside of the chamber 105 and the inside of the load lock chamber 106 for carrying in and out are evacuated by the vacuum pump 108 and an inert gas is supplied into the chamber 105. In FIG. 9, the direction in which the inert gas flows is indicated by an arrow 110. By using the load lock method in this manner, outside air can be prevented from flowing into the chamber 105, and the inside of the chamber 105 can be maintained in an inert gas atmosphere.

  In such a substrate manufacturing apparatus 101, it is necessary to provide the chamber 105 with a driving unit such as a conveying unit 104 that conveys the cooling body 103 at a predetermined path and speed in the chamber 105, and the chamber becomes large. Since the substrate can be grown in the thickness direction of the substrate from the surface of the cooling body 103, the manufacturing speed of the substrate can be increased. In this way, a substrate manufacturing apparatus with high substrate productivity is realized (for example, see Patent Document 2).

JP 2001-328992 A JP 2004-161583 A

  When the concentration of chemically active oxygen or the like is increased in the chamber 105, impurities are mixed into the melt 102 serving as a substrate material, and a substrate having high quality such as purity and crystallinity cannot be manufactured. Therefore, in the conventional substrate manufacturing apparatus 101 described above, the inside of the chamber 105 is evacuated and oxygen or the like is excluded by supplying an inert gas into the chamber 105. In order to keep the inside of the chamber 101 in a vacuum, however. In addition, a device for a vacuum environment such as the load lock chamber 106, the gate valve 107, and the vacuum pump 108 is required. Since a device for a vacuum environment is required in this way, there arises a problem that the substrate manufacturing apparatus 101 becomes complicated and large, the installation area increases, and the cost of the substrate manufacturing apparatus 101 increases.

  In addition, the crucible 111 that accommodates the melt 102 of the metal material or the semiconductor material is formed using quartz glass or carbon in order to prevent contamination of the material forming the crucible 111 with the melt 102. In particular, in the case of the disposable crucible 111, since carbon is lower in cost than quartz glass, it is often formed using carbon. For the same reason, drive devices such as the conveying means 104 provided in the chamber 105 are often formed using carbon.

Since carbon oxidizes and changes into gaseous carbon dioxide when it reaches a high temperature of 400 ° C. or higher in an oxygen atmosphere (chemical reaction formula: C + O ₂ → CO ₂ ), carbon forms when the concentration of oxygen in the chamber 105 increases. There is a problem that the crucible 111 and the driving device to be used are consumed. Therefore, in the conventional substrate manufacturing apparatus 101, in order to reduce the oxygen concentration in the chamber 105, oxygen in the chamber 105 is eliminated using a vacuum environment apparatus. As the manufacturing apparatus 101 becomes complicated and large, the installation area increases, and the cost of the substrate manufacturing apparatus 101 increases.

  Accordingly, an object of the present invention is to provide a substrate manufacturing apparatus capable of reducing the oxygen concentration in a chamber with a simple configuration.

The present invention is a substrate manufacturing apparatus for manufacturing a substrate by immersing a cooling body in a melt obtained by heating and melting a raw material of a substrate, and solidifying and growing the raw material on the surface of the cooling body,
A chamber comprising a crucible for storing the melt, and forming a housing space in which the crucible is housed;
Gas supply means for supplying an inert gas to the accommodation space;
It communicates with the accommodating space, and the communication hole cooling body can pass, discharge pores, and continues into the outer space, and the cooling body is transported holes passable is formed, communicating the communication hole, the exhaust hole and conveying hole A buffer chamber that forms a buffer space, and
Opening and closing means comprising a shutter capable of opening and closing the transport hole;
A conveying means for carrying the cooling body into the accommodating space through the communication hole and the conveying hole, and carrying the cooling body out of the accommodating space;
Is accommodated in the buffer space, seen including a gas jetting unit for jetting the inert gas toward the cooling body being conveyed buffer space by a conveying means,
The pressure in the accommodating space and the buffer space is higher than atmospheric pressure,
From the exhaust hole, the inert gas that is supplied from the gas supply means to the accommodation space and flows into the buffer chamber through the communication hole, and the gas ejected by the gas ejection means are exhausted. A substrate manufacturing apparatus characterized by the following.

The present invention also includes a plurality of the buffer chambers,
The gas supply means supplies the inert gas to the accommodation space so that the flow rates of the inert gas flowing into the buffer spaces through the communication holes of the buffer chambers are equal.

  In the invention, it is preferable that the volume of the buffer chamber is selected to be more than 0% and 10% or less of the volume of the chamber.

  Further, the present invention is characterized in that the gas ejection means is provided in the buffer space close to the transport hole.

Further, the present invention is characterized in that the opening / closing means is provided in the vicinity of the transport hole.
Further, the present invention is characterized in that the gas ejection means ejects an inert gas toward the exhaust hole.

  Further, the present invention is characterized in that the gas jetting means jets a gas to the outside of the region into a region surrounded by a virtual plane extending the inner peripheral surface facing the transport hole.

Further, in the present invention, the gas ejection means is formed to extend in a predetermined direction perpendicular to the direction in which the inert gas is ejected, and has an ejection hole through which the inert gas is ejected.
The width dimension of the ejection hole in the gas ejection direction and the direction perpendicular to the predetermined direction is selected to be 0.05 mm or more and less than 0.2 mm.

  The present invention is characterized in that the inert gas ejected from the gas ejection means is selected from at least one of a rare gas and a nitrogen gas.

According to the present invention, the inert gas is supplied to the accommodation space by the gas supply means. Since the pressure in the storage space and the buffer space is higher than the atmospheric pressure, the inert gas supplied to the storage space flows into the buffer space through the communication hole and is exhausted from the buffer space through the exhaust hole. The Therefore, even if a gas such as oxygen flows into the storage space, the gas flowing along the flow of the inert gas can be exhausted from the storage space and the buffer space, and the storage space can be filled with the inert gas. it can.

  The opening / closing means includes a shutter capable of opening and closing the transport hole. For example, the shutter opens the transport hole when the cooling body passes through the transport hole, and closes the transport hole when the cooling body does not pass through the transport hole. Accordingly, it is possible to prevent outside air such as air from flowing into the buffer space when the cooling body does not pass through the transport hole. Even if outside air such as air flows into the buffer space when the transport hole is open, the gas that has flowed in is exhausted from the exhaust hole together with the flow of inert gas flowing from the accommodation space through the buffer space to the exhaust hole. Therefore, it is possible to prevent outside air from flowing into the accommodation space.

The gas jetting means jets an inert gas toward the cooling body conveyed in the buffer space. By injecting the inert gas to the cooling body, it moves together with the cooling body carried into the buffer space from the outside of the substrate manufacturing apparatus, and the gas such as oxygen covering the cooling body can be separated from the cooling body. The pressure in the storage space and the buffer space is higher than atmospheric pressure, and the gas away from the cooling body is exhausted from the exhaust hole together with the flow of inert gas flowing from the storage space through the buffer space to the exhaust hole. It is possible to prevent outside air or the like from flowing into the accommodation space when the cooling body is transported to the accommodation space. Thus, without providing a device for a vacuum environment, it is possible to prevent the outside air from flowing into the accommodation space with a simple configuration, to fill the accommodation space with an inert gas, and to suppress the oxygen concentration to a low value. The substrate can be manufactured in an active gas atmosphere. This prevents impurities from being mixed into the substrate when the melt is solidified and grown. Furthermore, since the oxygen concentration in the accommodation space can be suppressed to a low value by preventing the outside air from flowing into the accommodation space, the apparatus provided in the chamber such as a crucible that becomes high temperature and the chamber are prevented from being oxidized and consumed. Thus, the lifetime of the substrate manufacturing apparatus can be extended. In addition, since it is not necessary to provide a device for a vacuum environment, it is possible to prevent the substrate manufacturing apparatus from becoming complicated and large in size and increasing the installation area, and to reduce the cost of the substrate manufacturing apparatus.

  Further, according to the present invention, the inert gas having the same flow rate flows through the communication hole of each buffer chamber by the gas supply means. When the flow rate of the inert gas flowing through one or more specific communication holes of the plurality of communication holes is small, outside air easily flows into the accommodation space from the communication holes having a low flow rate. Since the flow rates of the flowing inert gases are equal, it is possible to prevent outside air from flowing into the accommodation space. As a result, the oxygen concentration in the housing space can be reduced, impurities can be prevented from being mixed into the substrate as described above, and the life of the substrate manufacturing apparatus can be extended.

  Further, according to the present invention, the volume of the buffer chamber is selected to be greater than 0% and not greater than 10% of the chamber volume. Since the inert gas supplied from the gas supply means flows into the buffer space from the storage space, the pressure in the buffer space is at least higher than atmospheric pressure. If the pressure in the buffer space is higher than atmospheric pressure, it is possible to prevent outside air from flowing into the buffer space when the transfer hole is open. When the volume of the buffer chamber is larger than 10% of the volume of the chamber, the action of increasing the pressure of the buffer space is reduced, so that the difference between the atmospheric pressure and the pressure of the buffer space is reduced, and the outside air is The effect of preventing the inflow is reduced. If the volume of the buffer chamber is smaller than the volume of the chamber as in the present invention, the difference between the pressure of the buffer space and the atmospheric pressure becomes larger than when the volume of the buffer chamber is large, and the outside air flows into the buffer chamber. Can be efficiently prevented. As a result, the oxygen concentration in the housing space can be reduced, impurities can be prevented from being mixed into the substrate as described above, and the life of the substrate manufacturing apparatus can be extended.

  Further, according to the present invention, the gas jetting means is provided close to the transport hole in the buffer space. That is, the gas ejection means ejects the inert gas to the cooling body near the transport hole, not near the communication hole in the buffer space. As described above, the gas such as oxygen covering the cooling body is separated at a position away from the conveyance hole, so that the separated gas can be prevented from passing through the conveyance hole as much as possible, and the outside air can be prevented from flowing into the accommodation space. it can. As a result, the oxygen concentration in the housing space can be reduced, impurities can be prevented from being mixed into the substrate as described above, and the life of the substrate manufacturing apparatus can be extended.

  According to the present invention, since the opening / closing means is provided close to the transport hole, the gap between the opening / closing means and the transport hole is narrowed. Therefore, it is possible to prevent a gas such as air from flowing into the accommodation space from this gap. As a result, the oxygen concentration in the housing space can be reduced, impurities can be prevented from being mixed into the substrate as described above, and the life of the substrate manufacturing apparatus can be extended.

  Further, according to the present invention, since the gas ejection means ejects the inert gas toward the exhaust hole, a flow of the inert gas from the gas ejection means toward the exhaust hole occurs. By blowing out the inert gas along the flow of the inert gas, a gas such as oxygen separated from the cooling body can be smoothly conveyed to the exhaust hole. Accordingly, it is possible to prevent a gas such as oxygen separated from the cooling body from flowing into the accommodation space through the communication hole. As a result, the oxygen concentration in the housing space can be reduced, impurities can be prevented from being mixed into the substrate as described above, and the life of the substrate manufacturing apparatus can be extended.

  According to the invention, the gas jetting means jets the gas to the outside of the area into the area surrounded by the virtual plane extending the inner peripheral surface facing the transport hole. Since the gas is ejected to the outside of the region, the gas flow is not disturbed at the end of the region in the direction perpendicular to the direction in which the gas is ejected, and the outside air flowing from the transfer hole is more effectively exhausted. Can be exhausted. As a result, it is possible to prevent outside air from flowing into the accommodation space through the communication hole, thereby reducing the oxygen concentration in the accommodation space, and as described above, it is possible to prevent impurities from being mixed into the substrate, and to manufacture the substrate. The lifetime of the apparatus can be extended.

  According to the invention, the gas ejection means is formed to extend in a predetermined direction perpendicular to the direction in which the gas is ejected, and has an ejection hole through which the gas is ejected, in the direction in which the gas is ejected and in the predetermined direction. The width dimension of the ejection hole in the vertical direction is selected to be 0.05 mm or more and less than 0.2 mm. If the width dimension of the ejection hole is less than 0.05 mm, the flow rate becomes high when the flow rate is constant, so that the gas can be efficiently blown to the cooling body with a small amount of inert gas, but the pressure loss However, it becomes difficult for the inert gas to flow, and the flow rate of the inert gas in the direction in which the ejection holes extend becomes uneven. Further, if the width dimension of the ejection hole is 0.2 mm or more, the flow rate becomes low when the flow rate is constant, so that when the flow rate is increased, the flow rate of the inert gas increases and the use of the inert gas There is a problem that the production cost of the substrate increases due to the increase in the amount. In addition to these, considering the intersection when producing the ejection holes, the dimension of the width of the ejection holes is selected to be 0.05 mm or more and less than 0.2 mm, thereby suppressing the flow rate of the inert gas, The flow rate of the inert gas in the direction in which the ejection holes extend can be made uniform.

  According to the present invention, the inert gas ejected from the gas ejection means is selected as at least one of a rare gas and a nitrogen gas. Since the gas ejection means ejects such an inert gas, even if the inert gas ejected from the gas ejection means flows into the accommodation space through the communication hole, impurities are not mixed into the substrate. Further, the apparatus and chamber provided in a chamber such as a crucible at a high temperature will not be consumed by reacting with the inert gas ejected from the gas ejection means. As a result, as described above, impurities can be prevented from being mixed into the substrate, and the life of the substrate manufacturing apparatus can be extended.

  FIG. 1 is a cross-sectional view schematically showing a configuration of a substrate manufacturing apparatus 1 according to an embodiment of the present invention. The substrate manufacturing apparatus 1 includes a crucible 2, a chamber 3 that forms an accommodation space 9 in which the crucible 2 is accommodated, and a conveying means that holds and conveys a cooling body (hereinafter referred to as a base plate) 4 in the accommodation space 9. 5, one or a plurality of buffer chambers 6, a transport unit 7 that transports the cooling body 4 to the storage space 9, or transports the cooling body 4 out of the storage space 9, and an exhaust pipe 8. The substrate manufacturing apparatus 1 manufactures the substrate 12 by solidifying and growing the melt 11 on one surface 4 a in the thickness direction of the base plate 4 by immersing the plate-like base plate 4 in the melt 11. The substrate manufacturing apparatus 1 is used to manufacture a low-cost thin silicon substrate used for, for example, a solar cell.

  The chamber 3 further includes heating means provided so as to surround the crucible 2. The heating means is realized by a resistance heating device, an induction heating device, or the like. The heating means melts the raw material of the substrate 12 by heating the raw material of the solid substrate 12 filled in the crucible 2 to a high temperature equal to or higher than the melting point. The raw material of the substrate 12 is made of, for example, a metal material and a semiconductor material. The crucible 2 contains the liquid melt 11 melted by the heating means. In the present embodiment, crucible 2 is formed including carbon.

  The transport means 5 transports the base plate 4 and immerses it in the melt 11. The conveying means 5 is arranged on one side of the crucible 2 in the vertical direction Z (hereinafter referred to as the upper Z1) when the substrate manufacturing apparatus 1 is in use. Hereinafter, description will be made assuming the use state of the substrate manufacturing apparatus 1. The conveying means 5 includes a shaft body 18 that is rotatably supported around a first axis L1 parallel to a predetermined first direction X perpendicular to the vertical direction Z in the accommodation space 9, and the shaft body 18 to the first axis L1. And a plurality of arms 13 extending outward in the radial direction. The plurality of arms 13 are respectively arranged at predetermined intervals in the circumferential direction around the first axis L1. In FIG. 1, three arms 13 are shown as an example. An outer end portion in the radial direction around the first axis L <b> 1 of each arm 13 constitutes a holding portion 14 that holds the base plate 4. In the present embodiment, the holding portion 14 has a shape that fits with the base plate 4. Specifically, the holding portion 14 is formed with a groove between both end portions in the circumferential direction centering on the first axis L1, and the other surface portion in the thickness direction of the base plate 4 is perpendicular to the thickness direction. A convex groove extending in the direction is formed, and the convex groove and the concave groove are engaged with each other. The cross section perpendicular to the direction in which the groove extends is trapezoidal, and the lower base is formed closer to the shaft body 18 than the upper base. The cross section perpendicular to the direction in which the convex grooves extend is slightly smaller than the cross section of the concave grooves, and the lower base is formed at the other end in the thickness direction. The arm 13 holds the base plate 4 by fitting the convex groove of the base plate 4 and the concave groove of the holding portion 14. In this Embodiment, the conveyance means 5 is comprised including carbon.

  In a state where the arm 13 holds the base plate 4, the length of the arm 13 is such that one surface portion in the thickness direction of the base plate 4 is immersed in the melt 11 when the arm 13 is parallel to the vertical direction Z. Is set. Further, when the arm 13 is parallel to the vertical direction Z, the arm 13 holds the base plate 4 so that one surface 4 a in the thickness direction of the base plate 4 is parallel to the liquid surface of the melt 11. .

  The substrate manufacturing apparatus 1 further includes a gas supply unit 15 that supplies an inert gas to the accommodation space 9. The inert gas supplied by the gas supply means 15 is made of, for example, a rare gas such as argon and helium, a nitrogen gas, or the like. The gas supply means 15 has a gas supply pipe connected to one or a plurality of inert gas inflow holes 16 formed in the upper wall portion of the upper Z1 of the chamber 3. The gas supply means 15 supplies an inert gas to the chamber 3 from the inert gas inflow hole 16. In the present embodiment, two inert gas inflow holes 16 are provided in the upper wall portion of the chamber 3, and the inert gas is supplied from the two inert gas inflow holes 16. In the present embodiment, the gas supply means 15 supplies an inert gas having an equal flow rate from the inert gas inflow holes 16 to the accommodation space 9. By supplying the inert gas to the chamber 3 by the gas supply means 15, the gas such as oxygen flowing into the accommodation space 9 can be exhausted from the chamber 3, and the substrate 12 can be manufactured in the atmosphere of the inert gas. Since the substrate 12 is manufactured in an inert gas atmosphere as described above, it is possible to prevent the melt 11 from reacting with oxygen in the atmosphere and mixing impurities into the substrate 12. Furthermore, it can suppress that the conveyance means 5 and the crucible 2 are oxidized and consumed. In FIG. 1, the flow of the inert gas in the substrate manufacturing apparatus 1 is indicated by an arrow F1.

  In the present embodiment, the chamber 3 is formed symmetrically with respect to a predetermined second axis L2 parallel to the vertical direction Z. Accordingly, the two inert gas inflow holes 16 formed in the chamber 3 are also formed symmetrically with respect to the predetermined second axis L2. As described above, the gas supply means 15 supplies the inert gas having the same flow rate from the respective inert gas inflow holes 16 to the storage space 9, so that the inert gas flowing through the storage space 9 also has a predetermined second axis L2. On the other hand, it flows in line symmetry.

  The transport means 5 further includes drive means for rotationally driving the shaft body 18 while angularly displacing the shaft body 18 to one side F2 around the first axis L1. Each arm 13 rotates together with a shaft 18 that is rotationally driven by a driving unit while holding the base plate 4 conveyed by the conveying unit 7. In FIG. 1, each arm 13 rotates counterclockwise around the first axis L1. As the arm 13 rotates around the first axis L 1, the melt 11 flows from one surface 4 a in the thickness direction of the base plate 4 while the base plate 4 held by the arm 13 is immersed in the melt 11. The substrate 12 is formed by solidification growth. When the base plate 4 is separated from the melt 11, the base plate 4 is transported outside the accommodation space 9 by the transport means 7.

  The thickness of the substrate 12 formed on the base plate 4 depends on the temperature of the melt 11 and the rotational speed of the shaft body 18. The temperature of the melt 11 and the rotational speed of the shaft 18 are controlled by a control means that is realized including a central processing unit (abbreviated as CPU).

  An opening communicating with the buffer chamber 6 is formed in the chamber 3. The base plate 4 is carried into the accommodation space 9 through this opening or carried out of the accommodation space 9. The gas in the storage space 9 is exhausted out of the storage space 9 through this opening.

  FIG. 2 is an enlarged cross-sectional view of section II. The buffer chamber 6 includes a first buffer chamber 6 a through which the base plate 4 passes when the base plate 4 is carried into the storage space 9, and a second buffer chamber 6 b through which the base plate 4 passes when the base plate 4 is unloaded from the storage space 9. It is comprised including. Since the first buffer chamber 6a and the second buffer chamber 6b have the same structure and are arranged symmetrically with respect to the aforementioned predetermined second axis L2, the first buffer chamber 6a and the second buffer chamber 6b are arranged. Will be explained in common.

  The buffer chamber 6 includes a buffer chamber main body 19 that forms a buffer space 25, a communication pipe 20 that extends from the one side wall 29 facing the chamber 3 of the buffer chamber main body 19 to the chamber 3, and a communication pipe 20 of the buffer chamber main body 19. A transfer pipe 21 extending from the other side wall 30 facing the one side wall 29 to the opposite side of the chamber 3, and a connection pipe extending from the upper wall 31 of the upper Z 1 of the buffer chamber body 19 to the upper Z 1 and connected to the exhaust pipe 8. 22.

  A pipe line (hereinafter referred to as a communication hole) 17 formed by the communication pipe 20 communicates with the accommodation space 9 through an opening formed in the chamber 3, and the buffer space 25 communicates with the accommodation space 9 through the communication hole 17. . As described above, since the inert gas supplied from the gas supply means 15 flows symmetrically with respect to the predetermined second axis L2, the inert gas that flows into the buffer spaces 25 through the communication holes 17 respectively. The gas flow is equal. When the flow rate of the inert gas flowing through one or more specific communication holes 17 of the plurality of communication holes 17 is small, outside air easily flows into the accommodation space 9 from the communication holes 17 having a low flow rate. Since the flow rates of the inert gas flowing through the respective parts 17 are equal, it is possible to prevent the outside air from flowing into the accommodation space 9 from the buffer space 25. As a result, the oxygen concentration in the accommodation space 9 can be reduced.

  The base plate 4 is carried into the buffer space 25 from the outside of the substrate manufacturing apparatus 1 through a pipe line (hereinafter referred to as “transport hole”) 23 formed by the transport pipe 21, or from the buffer space 25 through the transport hole 23. It is carried out of the substrate manufacturing apparatus 1.

  The substrate manufacturing apparatus 1 further includes opening / closing means 24 that can open and close the transport hole 23. The opening / closing means 24 is provided close to the end of the buffer chamber 6 opposite to the chamber 3 side, that is, the end of the transfer tube 21 opposite to the buffer chamber main body 19 side. The opening / closing means 24 is a rectangular parallelepiped that can open and close the transport hole 23, a plate-shaped shutter 33, an air cylinder provided above the shutter 33, a rod that connects the shutter 33 and the air cylinder, And a linear guide that regulates movement. The shutter 33 is formed of a metal material, a resin material, or the like. The shutter 33 is provided so as to be movable only in the vertical direction Z, with the linear guide restricting movement in the direction other than the vertical direction Z. When the air cylinder presses or pulls the shutter 33 in the vertical direction Z through the rod, the shutter 33 moves in the vertical direction Z. Thus, the opening / closing operation of the transport hole 23 is performed by moving the shutter 33 in the vertical direction Z. The shutter 33 is formed so that the cross section perpendicular to the thickness direction is at least larger than the cross section of the transport hole 23 perpendicular to the direction in which the transport pipe 21 extends, and the shutter 33 is viewed from one side in the thickness direction of the shutter 33 when moved downward Z2. A shape covering the transport hole 23 is formed. When the base plate 4 passes through the transport hole 23, the shutter 33 moves upward Z1 to open the transport hole 23. Otherwise, the shutter 33 moves downward Z2 to close the transport hole 23. This prevents outside air from flowing into the buffer space 25 as much as possible. Further, since the opening / closing means 24 is provided close to the transport pipe 21, that is, close to the transport hole 23, the gap between the open / close means 24 and the transport hole 23 is narrowed. Therefore, gas such as air can be prevented from flowing into the accommodation space 9 from this gap. As a result, the oxygen concentration in the accommodation space 9 can be reduced, impurities can be prevented from being mixed into the substrate 4, and the life of the substrate manufacturing apparatus 1 can be extended.

  The connection pipe 22 extends upward Z1 from the end of the upper wall 31 of the buffer chamber body 19 opposite to the chamber 3 side. The exhaust pipe 8 extends from the connecting pipe 22 formed in each buffer chamber 6 to the upper Z1 and extends horizontally from the end of the upper Z1 so as to be connected to the upper Z1 of the chamber 3, respectively. An opening 27 is formed in the upper wall of the upper portion Z <b> 1 of the connecting portion 26 of the exhaust pipe 8. The inert gas supplied to the chamber 3 from the gas supply means 15 is formed by the chamber 3, the communication hole 17, the buffer space 25, a pipe line (hereinafter referred to as an exhaust hole) 34 formed by the connection pipe 22, and the exhaust pipe 8. Then, the air is exhausted out of the substrate manufacturing apparatus 1 through the pipe line and the opening 27 formed in the connecting portion 26 of the exhaust pipe 8 in this order.

  In the present embodiment, the volume of the buffer chamber 6, that is, the volume of the buffer space 25, the volume of the communication hole 17, the volume of the transfer hole 23, and the volume of the exhaust hole 34 is the volume of the chamber 3. That is, it is selected to exceed 0% and not more than 10% of the volume of the accommodation space 9. Since the inert gas supplied from the gas supply means 15 flows into the buffer space 25 from the storage space 9, the pressure in the buffer space 25 is at least higher than atmospheric pressure. If the pressure in the buffer space 25 is higher than atmospheric pressure, it is possible to prevent outside air from flowing into the buffer space 25 when the transport hole 23 is open. When the volume of the buffer chamber 6 is larger than 10% of the volume of the chamber 3, the action of increasing the pressure of the buffer space 25 is reduced, so that the difference between the atmospheric pressure and the pressure of the buffer space 25 is reduced. The effect of preventing outside air from flowing into the buffer space 25 is reduced. If the volume of the buffer chamber 6 is sufficiently smaller than the volume of the chamber 3 as in the present embodiment, the difference between the pressure in the buffer space 25 and the atmospheric pressure is larger than when the volume of the buffer chamber 6 is large. Thus, the outside air can be efficiently prevented from flowing into the buffer chamber 6. As a result, the oxygen concentration in the buffer space 25 can be reduced, and accordingly, the oxygen concentration in the accommodation space 9 can be reduced.

  The transport unit 7 transports the base plate 4 carried into the buffer chamber 6 to the transport unit 5 provided in the accommodation space 9, or transports the base plate 4 transported by the transport unit 5 to the buffer chamber 6. The conveying means 7 is, for example, two rails that extend in parallel, a plurality of shafts that extend in a direction perpendicular to the extending direction of the two rails, and whose both ends are pivotally supported by each rail, and are pivotally supported by each shaft. And a plurality of conveying rollers arranged at equal intervals in the axial direction of the shaft, and a driving body that rotationally drives each shaft around the axis. Each shaft is arranged at equal intervals in the extending direction of the two rails. Each shaft is provided with three or more meteorite-shaped conveyance rollers, and each conveyance roller rotates together with the shaft. As will be described later, an inert gas is ejected from the gas ejection means 35 toward the transport means 7 from the lower Z2 toward the upper Z1. The conveying roller and the shaft are arranged at a sufficient interval so as not to disturb the flow of the inert gas from the gas ejection means 35. Thus, the conveying means 7 conveys the base plate 4 placed on the conveying roller from the upper side Z1 of the conveying means 7 in the direction in which the two rails extend as each shaft rotates. The conveyance direction of the base plate 4 is switched depending on the rotation direction of the shaft. The base plate 4 transported to the transporting means 5 by the transporting means 7 is held by fitting with the holding portion 14 of the transporting means 5 as described above, and is immersed in the melt 11 by the transporting means 5 and transported to the transporting means 7. Further, it is transferred to the buffer chamber 6 by the transfer means 7.

  FIG. 3 is a cross-sectional view of the buffer chamber 6 as seen from the section line III-III in FIG. The substrate manufacturing apparatus 1 further includes gas ejection means 35 in the buffer space 25. The gas ejection means 35 is provided in the buffer space 25 close to the transport hole 23. Specifically, in the present embodiment, the gas ejection means 35 is provided at the end of the buffer chamber body 19 near the transport pipe 21 on the lower wall 36 of the lower side Z2. The gas jetting unit 35 extends along the other side wall 30 between both end portions in the first direction X perpendicular to the vertical direction Z of the other side wall 30. An ejection hole extending between both end portions in the first direction X is formed at the end portion of the upper Z1 of the gas ejection means 35. The gas ejection means 35 includes an inert gas supply source that supplies an inert gas to the ejection holes, and ejects the inert gas from the ejection holes toward the upper side Z1. In the present embodiment, the ejection holes of the gas ejection means 35 are elongated holes extending in the direction in which the gas ejection means 35 extends (first direction X), and the inner peripheral surface facing the ejection holes is a rectangular tube. Has a shape. In FIG. 3, the flow of the inert gas ejected from the gas ejection holes is indicated by arrows 38. As described above, since the connection pipe 22 is provided at the end of the upper wall 31 of the buffer chamber body 19 near the transport pipe 21, the gas ejection means 35 is located below the exhaust hole 34 at the Z 2, and is connected to the exhaust hole 34. Inert gas is spouted out.

  The transport pipe 21 described above has a rectangular cylindrical shape, and an opening 37 through which the transport hole 23 communicates is formed on the other side wall 30 of the buffer chamber body 19. This opening 37 extends in the first direction X in the same manner as the direction in which the gas ejection means 35 extends, and is located above the gas ejection means 35 as viewed from one of the vertical direction Z and the second direction Y perpendicular to the first direction X. Formed. Further, the opening 37 is formed at the center of the gas ejection hole in the first direction X. The width dimension W1 in the direction in which the gas ejection holes extend (hereinafter referred to as the width dimension W1 in the longitudinal direction of the gas ejection holes) is the width dimension in the direction in which the gas ejection means 35 of the opening 37 formed in the other side wall 30 extends. A value larger than W2 (hereinafter, referred to as a dimension W2 in the longitudinal direction of the opening 37) is selected, and is preferably selected to be 1.5 times the dimension W2 in the longitudinal direction of the opening 37. That is, the gas ejecting means 35 ejects gas over the outside of the region into a region (region in the opening 37 in FIG. 3) surrounded by a virtual plane extending the inner peripheral surface facing the transport hole 23. The flow of the inert gas ejected from the gas ejection hole is disturbed at the end in the direction in which the gas ejection hole extends. Therefore, if the gas is ejected only to the region, the flow of the inert gas is disturbed. The outside air flowing from the transport hole 23 cannot be effectively exhausted to the exhaust hole 34. Since the gas ejection means 35 ejects the gas to the outside of the region, the flow of the inert gas is not disturbed in the region, and the outside air flowing from the transfer hole 23 is more effectively exhausted to the exhaust hole 34. be able to. Accordingly, it is possible to prevent the outside air from flowing into the accommodation space 9 through the communication hole 17 and to reduce the oxygen concentration in the accommodation space 9.

  The base plate 4 passes through the upper Z1 of the gas ejection means 35 when it is carried into the buffer space 25 through the transport hole 23 by the transport means 7. At this time, since the gas ejection means 35 ejects the inert gas toward the base plate 4 passing through the upper Z1, the outside air transported covering the base plate 4 is separated from the base plate 4. In FIG. 2, the oxygen gas 28 is schematically indicated by a symbol “◯”, and the direction in which the oxygen gas 28 flows by the inert gas ejected from the gas ejection means 35 is indicated by an arrow 32. In particular, as described above, the gas ejection means 35 is provided close to the transport hole 23 in the buffer space 25. That is, the gas ejection means 35 ejects the inert gas to the base plate 4 not near the communication hole 17 but near the transport hole 23 in the buffer space 25. Since the gas such as oxygen covering the base plate 4 is separated at a position away from the transport hole 23 in this way, it is possible to prevent the separated gas from passing through the transport hole 23 as much as possible, and the outside air flows into the accommodation space 9. Can be prevented. As a result, the oxygen concentration in the accommodation space 9 can be reduced.

  Further, as described above, the gas ejection means 35 is located below the exhaust hole 34 Z2 and ejects the inert gas toward the exhaust hole 34, so that the inert gas swirls or stays in the buffer space 25. Without flowing, an inert gas flow from the gas ejection means 35 toward the exhaust hole 34 is generated. A gas such as oxygen separated from the base plate 4 can be smoothly conveyed to the exhaust hole 34 by ejecting the inert gas along the flow of the inert gas. Accordingly, it is possible to prevent a gas such as oxygen separated from the base plate 4 from flowing into the accommodation space 9 through the communication hole 17.

  Furthermore, since the outside air flowing into the buffer space 25 from the transport hole 23 when the shutter 33 is in the open state can be conveyed to the exhaust hole 34 along the gas flow from the gas ejection means 35, the outside air is communicated with the communication hole 17. It is possible to prevent the air from flowing into the accommodation space 9. That is, a barrier (hereinafter referred to as an inert gas curtain) that blocks the outside air from flowing from the transport hole 23 through the buffer space 25 and the communication hole 17 into the accommodation space 9 by the inert gas ejected from the gas ejection means 35. ) Is formed. The inert gas curtain has a function of transporting gas passing through itself to the communication hole 17.

  The effect of the inert gas curtain will be described based on experimental results. FIG. 4 is a diagram showing the relationship between the flow rate of the inert gas ejected from the gas ejection means 35 and the oxygen concentration in the accommodation space 9. In FIG. 4, the horizontal axis indicates the flow rate of the inert gas ejected from the gas ejection means 35 (hereinafter referred to as curtain flow rate), and the vertical axis indicates the oxygen concentration in the accommodation space 9. The measurement result of the oxygen concentration shown in FIG. 4 is a measurement value when the flow rate of the inert gas supplied to the accommodation space 9 from the gas supply means 15 (hereinafter referred to as chamber flow rate) is 200 L / min.

  As shown in FIG. 4, the oxygen concentration in the accommodation space 9 decreases as the curtain flow rate increases, indicating that the inert gas curtain functions as a barrier that blocks outside air flowing into the accommodation space 9. . In FIG. 4, when the curtain flow rate is less than 20 L / min, the oxygen concentration in the accommodation space 9 rapidly increases, indicating that the inert gas curtain blocking effect does not function as effectively as practical. When the curtain flow rate is 20 L / min or more, the oxygen concentration in the accommodation space 9 can be kept below about 35 ppm, so that the effect of the inert gas curtain functioning as a barrier that blocks outside air flowing into the accommodation space 9 is remarkable. Is shown to appear. In particular, when the curtain flow rate is 100 L / min or more, the oxygen concentration in the accommodation space 9 can be maintained at 5 ppm or less, so that the inert gas curtain functions as a barrier that blocks outside air flowing into the accommodation space 9. It is shown to be particularly prominent. Therefore, in the substrate manufacturing apparatus 1 of the present embodiment, the curtain flow rate is selected to be 20 L / min or more, preferably 100 L / min or more.

In general, if the substrate manufacturing apparatus 1 such as the chamber 3, the buffer chamber 6, and each hole has a different shape, the correlation between the curtain flow rate and the oxygen concentration in the accommodation space 9 is different, but according to the theory of fluid dynamics, the following equation (1 If the Reynolds number Re and the Schmidt number Sc defined by (2) are equal, the flow velocity distribution and the concentration distribution are similar to each other from the similarity law of the flow velocity distribution and the concentration distribution. Therefore, it is estimated that the oxygen concentration in the accommodation space 9 depends on the Reynolds number Re and the Schmitt number Sc regardless of the shape of the substrate manufacturing apparatus 1.
Re = UL / ν
Sc = ν / D (1)

The Reynolds number Re and the Schmitt number Sc are dimensionless numbers. In the formula (1), U represents a representative flow velocity (unit m / s), L represents a representative length {4 × opening area / opening circumference (unit m)}, and ν represents an inert gas. kinematic viscosity indicates the factor (unit m ² / s), [nu's, indicates the dynamic viscosity of the inert gas (in m ² / s), D is the diffusion coefficient for the inert gas of oxygen (in m ² / s).

  Even if the shape of the substrate manufacturing apparatus 1 is changed, if the type of the inert gas is not changed, the combination of the inert gas and oxygen does not change, so the Schmitt number Sc is always unchanged and constant. Therefore, if the Reynolds number Re is the same, the oxygen concentration in the accommodation space 9 is estimated to be equal regardless of the shape of the substrate manufacturing apparatus 1. That is, even if the shape of the substrate manufacturing apparatus 1 is different, it is estimated that the correlation between the oxygen concentration in the accommodation space 9 and the Reynolds number Re is the same. Since the Reynolds number Re is determined from the oxygen concentration of the target accommodating space 9, and the representative length L is obtained from the shape of the substrate manufacturing apparatus 1, the representative flow velocity U can be obtained from the equation (1). When the representative flow velocity U is obtained, the curtain flow rate to be ejected from the gas ejection means 35 can be determined.

  In the present embodiment, there is one communication hole 17 and the size of the gas ejection hole is 500 mm × 0.1 mm. For example, when the curtain flow rate is 100 L / min, the Reynolds number Re (hereinafter referred to as curtain curtain) 35 of the gas ejection means 35 is used. The Reynolds number Re is 460, and the curtain Reynolds number Re is 92 when the curtain flow rate is 20 L / min. When the above-described experimental results are analyzed with reference to the Curtain Reynolds number Re, when the Curtain Reynolds number Re is 460 or more, the oxygen concentration in the accommodation space 9 is maintained at 5 ppm or less due to the blocking effect of the inert gas curtain. . When the Curtain Reynolds number Re becomes less than 460, the oxygen concentration in the accommodation space 9 starts to increase, and as the Curtain Reynolds number Re decreases, the oxygen concentration in the accommodation space 9 increases, and finally the Curtain Reynolds number. When the number Re is less than 92, the oxygen concentration increases rapidly, indicating that the blocking effect of the inert gas curtain does not function as effectively as practical. Therefore, regardless of the shape of the substrate manufacturing apparatus 1, the curtain Reynolds number Re is selected to be 92 or more, preferably 460 or more.

  Similarly, the effect of supplying the inert gas to the accommodation space 9 by the gas supply means 15 will be described based on the experimental results. FIG. 5 is a diagram showing the relationship between the chamber flow rate and the oxygen concentration in the accommodation space 9. In FIG. 5, the horizontal axis indicates the chamber flow rate, and the vertical axis indicates the oxygen concentration in the accommodation space 9. The measurement result of the oxygen concentration shown in FIG. 5 is a measurement value when the curtain flow rate is 100 L / min.

  As shown in FIG. 5, as the chamber flow rate increases, the oxygen concentration in the storage space 9 decreases, so that the inert gas supplied to the storage space 9 by the gas supply means 15 flows into the storage space 9 from the outside air. It is shown that the outside air flowing into the storage space 9 is exhausted outside the storage space 9 and the exhaust effect of reducing the oxygen concentration in the storage space 9 is exhibited. In FIG. 5, when the chamber flow rate is less than 100 L / min, the oxygen concentration in the accommodation space 9 rapidly increases, and it is shown that the exhaust effect by the inert gas supplied from the gas supply means 15 does not function as effectively as practical. It is. When the chamber flow rate is 100 L / min or more, the oxygen concentration in the accommodation space 9 can be kept below about 70 ppm, which indicates that the exhaust effect by the inert gas supplied from the gas supply means 15 appears remarkably. In particular, when the chamber flow rate is 300 L / min or more, the oxygen concentration in the accommodation space 9 can be kept at about 10 ppm or less, and thus the exhaust effect by the inert gas supplied from the gas supply means 15 may be particularly noticeable. Indicated. Therefore, in the substrate manufacturing apparatus 1 of the present embodiment, the chamber flow rate is selected to be 100 L / min or more, and preferably 300 L / min or more.

  The experimental results described above are analyzed based on the Reynolds number Re according to the similarity law of flow velocity distribution and concentration distribution as in the case of the inert gas curtain. In the present embodiment, since there is one communication hole 17 and the size is 400 mm × 100 mm, for example, the Reynolds number Re (hereinafter referred to as the chamber Reynolds number Re) of the communication hole 17 when the chamber flow rate is 300 L / min is 1100. The chamber Reynolds number Re when the chamber flow rate is 200 L / min is 734, the chamber Reynolds number Re when the chamber flow rate is 150 L / min is 550, and the chamber reynolds number Re when the chamber flow rate is 100 L / min. The Reynolds number Re is 367. When the chamber Reynolds number Re is 1100 or more, the oxygen concentration is maintained at about 10 ppm by the exhaust effect. When the chamber Reynolds number Re becomes less than 1100, the oxygen concentration starts to rise, and as the chamber Reynolds number Re decreases, the oxygen concentration rises. When the chamber Reynolds number Re finally becomes less than 367, the exhaust gas is exhausted. It is shown that the effect does not function as effectively as is practical. Therefore, regardless of the shape of the substrate manufacturing apparatus 1, the chamber Reynolds number Re is selected to be 367 or more, preferably 1100 or more.

  As described above, when the oxygen concentration in the target accommodation space 9 is determined, the curtain Reynolds number Re and the chamber Reynolds number Re for achieving this oxygen concentration are determined based on FIGS. 4 and 5, respectively. Is done. Using the equation (1), from the curtain Reynolds number Re and the chamber Reynolds number Re, the newly designed substrate manufacturing apparatus 1 communicates with the representative flow velocity U of the inert gas flowing from the gas ejection holes and the accommodation space 9. A typical flow rate U of the inert gas through the hole 17 can be calculated, and the curtain flow rate and the chamber flow rate can be estimated by multiplying the flow rate by the opening area. As described above, the curtain flow rate and the chamber flow rate can be estimated in advance at the time of design, and the design can be made in consideration of the use amount of the inert gas and the oxygen concentration of the accommodation space 9.

  According to the substrate manufacturing apparatus 1 of the present embodiment described above, the inert gas supplied to the accommodation space 9 by the gas supply means 15 flows into the buffer space 25 through the communication hole 17 and passes through the exhaust hole 34. The air is exhausted from the buffer space 25 through. Therefore, even if a gas such as oxygen flows into the storage space 9, the gas flowing in along the flow of the inert gas can be exhausted from the storage space 9 and the buffer space 25, and the storage space 9 is made to be inert gas. Can be satisfied by.

  The shutter 33 opens the transport hole 23 when the base plate 4 passes through the transport hole 23, and closes the transport hole 23 when the base plate 4 does not pass through the transport hole 23. Accordingly, it is possible to prevent outside air such as air from flowing into the buffer space 25 when the base plate 4 does not pass through the transport hole 23. Even if outside air such as air flows into the buffer space 25 when the transport hole 23 is open, the gas that has flowed in is exhausted together with the flow of inert gas flowing from the storage space 9 through the buffer space 25 to the exhaust hole. Since air is exhausted from the hole 34, it is possible to prevent outside air from flowing into the accommodation space 9.

  The gas ejection means 35 ejects an inert gas toward the base plate 4 conveyed in the buffer space 25. By injecting an inert gas onto the base plate 4, the base plate 4 is moved together with the base plate 4 carried into the buffer space 25 from outside the substrate manufacturing apparatus 1, and a gas such as oxygen covering the base plate 4 is separated from the base plate 4. Can do. Thus, the gas away from the base plate 4 is exhausted from the exhaust hole 34 together with the flow of the inert gas flowing from the storage space 9 through the buffer space 25 to the exhaust hole 34, so that the base plate 4 is stored in the storage space 9. It is possible to prevent outside air or the like from flowing into the accommodation space 9 when transported to the storage space 9. Thus, without providing a device for a vacuum environment, it is possible to prevent the outside air from flowing into the accommodation space 9 with a simple configuration, to fill the accommodation space 9 with an inert gas, and to suppress the oxygen concentration to a low value. The substrate can be manufactured in an inert gas atmosphere. Thereby, it is possible to prevent impurities from being mixed into the substrate 12 when the melt 11 is solidified and grown. Furthermore, since the outside air can be prevented from flowing into the storage space 9 and the oxygen concentration in the storage space 9 can be kept to a low value, the apparatus and the chamber provided in the storage space 9 such as the crucible 2 at a high temperature are oxidized and consumed. Thus, the life of the substrate manufacturing apparatus 1 can be extended. In particular, in the present embodiment, the crucible 2 and the transporting means 5 are formed to contain carbon, so that the crucible 2 and the transporting means 5 are oxidized and consumed by suppressing the oxygen concentration in the accommodation space 9 to a low value. Can be prevented. Since the oxygen concentration in the accommodation space 9 can be suppressed to a low value with a simple configuration without providing a device for a vacuum environment like the substrate manufacturing device 101 of the prior art, the substrate manufacturing device 1 can be downsized. Thus, the installation area is reduced, and the low-cost substrate manufacturing apparatus 1 can be realized.

  In the substrate manufacturing apparatus 1 of the present embodiment, the gas jetting means 35 is provided on the lower wall 36 of the lower Z2 of the buffer chamber body 19 and jets an inert gas to the upper Z1. As long as the inert gas is ejected toward the exhaust hole 34, it may be disposed at any position.

  FIG. 6 is a cross-sectional view of the buffer chamber 6 when the gas ejection means 35 is provided on the one side wall 39 in the first direction X of the buffer chamber body 19. When the gas ejection means 35 is provided on the one side wall 39 in the first direction X of the buffer chamber body 19, the connecting pipe 22 extends from the other side wall 40 of the buffer chamber body 19 to the other side in the first direction X. It is formed to extend. The gas ejection means 35 ejects an inert gas to the other side in the first direction X toward the exhaust pipe 8. The gas ejection means 35 is provided at an end portion of the one side wall 39 in the first direction X of the buffer chamber body 19 near the transport pipe 21. The gas ejection means 35 extends along the one side wall 39 across both end portions in the up-down direction Z of the one side wall 39. At the other end portion in the first direction of the gas ejection means 35, an ejection hole extending between both end portions in the vertical direction Z is formed. The gas ejection means 35 ejects an inert gas from the ejection hole toward the other side in the first direction X. The ejection hole of the gas ejection means 35 is a long hole that is long in the extending direction (vertical direction Z) of the gas ejection means 35, and the inner peripheral surface facing the ejection hole has a square cylindrical shape. In FIG. 6, the flow of the inert gas ejected from the gas ejection holes is indicated by arrows 41.

  As described above, the opening 37 by the transport hole 23 is formed in the other side wall 30 in the second direction Y of the buffer chamber body 19. The opening 37 extends in the first direction X, and is formed on the other side in the first direction X of the gas ejection means 35 when viewed from one side in the second direction Y. Further, the opening 37 is formed in the central portion of the gas ejection hole in the vertical direction Z. The width dimension W3 in the direction in which the gas ejection holes extend (hereinafter referred to as the width dimension W3 in the longitudinal direction of the gas ejection holes) is the width dimension in the direction in which the gas ejection means 35 of the opening 37 formed in the other side wall 30 extends. It is selected to be larger than W4 (hereinafter referred to as the width dimension W4 of the opening 37 in the short direction), preferably 1.5 times the width dimension W4 of the opening 37 in the short direction. By designing the shape of the gas ejection holes in this way, as described above, the inert gas in the region (the region in the opening 37 in FIG. 3) surrounded by the virtual plane extending the inner peripheral surface facing the transport hole 23. Therefore, the outside air flowing in from the transport hole 23 can be effectively exhausted to the exhaust hole 34. Accordingly, it is possible to prevent the outside air from flowing into the accommodation space 9 through the communication hole 17 and to reduce the oxygen concentration in the accommodation space 9.

  In the substrate manufacturing apparatus 1 of the present embodiment, the chamber 3 and the buffer chamber 6 are formed symmetrically with respect to the second axis L2, but may not be symmetrical. In this case, the gas supply means 15 flows into the buffer spaces 25 through the communication holes 17 of the buffer chambers 6 by adjusting the flow rate of the inert gas flowing from the inert gas inflow holes 16. The inert gas is supplied to the accommodation space 9 so that the flow rates of the inert gas are equal. As a result, it is possible to prevent outside air from flowing into the accommodation space 9 from the buffer space 25 as described above, and to reduce the oxygen concentration in the accommodation space 9.

  FIG. 7 is a sectional view of the buffer chamber 6 of the substrate manufacturing apparatus 1 according to another embodiment of the present invention. The substrate manufacturing apparatus 1 of the present embodiment has the same configuration except for the structure of the substrate manufacturing apparatus 1 of the above-described embodiment and the buffer chamber 6, so that the corresponding parts are denoted by the same reference numerals. The duplicated explanation is omitted.

  The communication tube 20 extends from the end of the buffer chamber body 19 near the chamber 3 toward the chamber 3 in a tapered manner. Accordingly, the communication hole 17 is also tapered from the buffer space 25 toward the accommodation space 9. In other words, the communication pipe 20 is formed so that the opening area of the communication pipe 20 becomes smaller from the buffer space 25 toward the accommodation space 9.

  The connection pipe 22 is formed so that a cross section perpendicular to the vertical direction Z increases as the distance from the upper wall 31 of the buffer chamber body 19 increases to the upper Z1. Accordingly, the cross-sectional area of the exhaust hole 34 perpendicular to the vertical direction Z, that is, the opening area of the connecting pipe 22 is formed so as to increase as the distance from the buffer chamber main body 19 increases upward Z1.

  The transport pipe 21 is formed such that a cross section perpendicular to the extending direction of the transport pipe 21 increases as the distance from the other side wall 30 of the buffer chamber body 19 to the side opposite to the chamber 3 increases. Therefore, the area of the cross section of the transport hole 23 perpendicular to the direction in which the transport pipe 21 extends, that is, the opening area of the transport pipe 21 is formed to increase as the distance from the buffer chamber body 19 increases.

  In the case of a circular pipe, the resistance due to the gas flow path is inversely proportional to the inner diameter and proportional to the square of the flow velocity. Therefore, in the case of a channel having a taper shape, the inner diameter decreases and the flow velocity increases as the cross-sectional area of the channel decreases, so that the resistance by the channel increases. That is, the gas flows more easily in the direction in which the cross-sectional area of the flow path becomes larger than in the direction in which the cross-sectional area of the flow path decreases. Since the communication pipe 20 has the above-described taper shape, it is easier for gas to flow from the storage space 9 through the communication pipe 20 to the buffer space 25 than when gas flows from the buffer space 25 through the communication hole 17 to the storage space 9. . As a result, the outside air can be prevented from flowing into the accommodation space 9 from the buffer chamber body 19, and the oxygen concentration of the accommodation space 9 can be kept at a low value.

  Further, since the connecting pipe 22 has the tapered shape described above, it is difficult for gas to flow into the buffer space 25 from the pipe line formed by the exhaust pipe 8, and gas containing oxygen or the like exhausted from the buffer space 25 enters the buffer space 25. Backflow can be prevented. Further, since the transport pipe 21 has the above-described tapered shape, it is difficult for outside air to flow into the buffer space 25 through the transport hole 23. By these, the oxygen concentration of the buffer space 25 can be kept at a low value, and as a result, the oxygen concentration of the accommodation space 9 can be kept at a low value. As a result, it is possible to prevent impurities from being mixed into the substrate 12 as described above, and to extend the life of the substrate manufacturing apparatus 1.

  FIG. 8 is a sectional view showing a substrate manufacturing apparatus 51 according to still another embodiment of the present invention. The substrate manufacturing apparatus 51 of the present embodiment further includes a replenishing means 52 for replenishing the raw material 69 of the substrate 12 in addition to the substrate manufacturing apparatus 1 of each of the above-described embodiments. Since the substrate manufacturing apparatus 51 of the present embodiment is configured by adding the replenishing means 52 to the substrate manufacturing apparatus 1 of each of the above-described embodiments, the corresponding parts are denoted by the same reference numerals and only the replenishing means 52 is provided. Explain and omit duplicate description. In FIG. 8, the conveying means 5, the base plate 4, the conveying means 7 and the gas supply means 15 are omitted for easy understanding.

  Since the substrate manufacturing apparatus 51 manufactures the substrate 12 by immersing the base plate 4 in the melt 11 and growing the crystal of the melt 11, the melt 11 that becomes the raw material 69 of the substrate 12 every time the substrate 12 is manufactured. Will decrease. When the melt 11 is reduced, the replenishing means 52 supplies the crucible 2 with a raw material 69 such as a solid or liquid metal material and a semiconductor material in order to supplement the reduced amount of the raw material 69. In the present embodiment, the replenishing means 52 supplies the solid raw material 69 to the crucible 2.

  The replenishment means 52 extends into the accommodation space 9 through a replenishment buffer chamber 53 provided in the upper Z1 of the chamber 3 and an opening formed in the upper wall 54 of the upper Z1 of the chamber 3 from the replenishment buffer chamber 53. The replenishment pipe 55, the replenishment transport pipe 57 extending from the upper wall 56 of the upper Z1 of the replenishment buffer chamber 53 to the upper side Z1, and the other side wall 61 in the second direction Y of the replenishment buffer chamber 53 from the second direction Y. The connection pipe 62 is connected to the exhaust pipe 8 and is connected to the exhaust pipe 8, the gas ejection means 64 disposed on one side wall 63 in the second direction Y of the supply buffer chamber 53, and the supply transport pipe 57. Open / close means including a shutter capable of opening and closing a pipe line (hereinafter referred to as a replenishment transport hole) 65.

  The shutter 66 opens the supply transport hole 65 when the raw material 69 is supplied to the crucible 2, and closes the supply transport hole 65 at other times. When the replenishment transport hole 65 is opened, the raw material 69 is supplied to the buffer space 68 formed by the replenishment buffer chamber 53, and further supplied to the crucible 2 through the conduit 70 formed by the replenishment pipe 55. Is done.

  Similarly to the gas ejection means 35 of each of the above-described embodiments, the gas ejection means 64 ejects an inert gas toward the pipe 71 formed by the connection pipe 63, whereby the gas ejection means 64 and the connection pipe An inert gas is jetted toward the raw material 69 that passes between the two. As described above, the gas ejection means 64 ejects the inert gas, so that the outside air can be prevented from flowing into the accommodation space 9 as described above, and the oxygen concentration in the accommodation space 9 can be kept at a low value. . As a result, it is possible to prevent impurities from being mixed into the substrate 12 as described above, and to extend the life of the substrate manufacturing apparatus 1.

  In the substrate manufacturing apparatus 51 according to still another embodiment of the present embodiment, in addition to the configuration of the substrate manufacturing apparatus 1 described above, a recovery unit that recovers fragments of the substrate 12 is further provided. When the substrate 12 formed on the one surface 4 a of the base plate 4 is separated from the melt 11, the substrate 12 is rapidly cooled from high temperature to low temperature. Debris may fall on the wall. The recovery means recovers the reused fragments of the substrate 12 that have dropped onto the lower wall of the chamber.

  The collection means includes a tray disposed at a position where the fragments of the substrate 12 are likely to fall, and a transport unit that transports the trays that accommodate the fragments of the substrate 12 to the outside from the accommodation space 9. The chamber 3 is formed with an opening through which the recovery means passes, and the buffer chamber 6 having the same configuration as the buffer chamber 6 of each of the embodiments described above is connected to the opening that forms the opening. Further, the gas ejection means 35 is provided in the buffer space 25 as in the above-described embodiments, and the opening / closing means 24 is provided.

  As described above, the inert gas ejected from the gas ejection means 35 forms a barrier that blocks outside air from flowing from the transport hole 23 through the buffer space 25 and the communication hole 17 into the accommodation space 9. This prevents the outside air from flowing into the storage space 9 when the tray is carried into or out of the buffer chamber 6, and the oxygen concentration in the storage space 9 can be kept at a low value.

It is sectional drawing which shows typically the structure of the board | substrate manufacturing apparatus 1 of one Embodiment of this invention. It is an expanded sectional view of Section II. It is sectional drawing of the buffer chamber 6 seen from the cut surface line III-III of FIG. FIG. 4 is a diagram showing the relationship between the flow rate of inert gas ejected from the gas ejection means 35 and the oxygen concentration in the accommodation space 9. It is a figure which shows the relationship between a chamber flow rate and the oxygen concentration of the accommodation space. FIG. 4 is a cross-sectional view of the buffer chamber 6 when the gas ejection means 35 is provided on one side wall 39 in the first direction X of the buffer chamber body 19. It is sectional drawing of the buffer chamber 6 of the board | substrate manufacturing apparatus 1 of other embodiment of this invention. It is sectional drawing which shows the board | substrate manufacturing apparatus 51 of further another embodiment of this invention. It is sectional drawing which shows the board | substrate manufacturing apparatus 101 of another conventional technique.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,51 Substrate manufacturing apparatus 2 Crucible 3 Chamber 4 Base plate 5 Transport means 6 Buffer chamber 7 Transport means 8 Exhaust pipe 9 Accommodating space 11 Melt 12 Substrate 15 Gas supply means 17 Communication hole 20 Communication pipe 21 Transport pipe 22, 62 Connection Pipe 23 Transport hole 24, 67 Opening / closing means 25, 68 Buffer space 26 Connecting portion 33, 66 Shutter 34 Exhaust hole 35 Gas ejection means 52 Replenishment means 53 Replenishment buffer chamber 55 Replenishment pipe 57 Replenishment transport pipe 64 Gas ejection means 65 Supply hole for replenishment

Claims (9)

A substrate manufacturing apparatus for manufacturing a substrate by immersing a cooling body in a melt obtained by heating and melting a raw material of a substrate, and solidifying and growing the raw material on the surface of the cooling body,
A chamber comprising a crucible for storing the melt, and forming a housing space in which the crucible is housed;
Gas supply means for supplying an inert gas to the accommodation space;
It communicates with the accommodating space, and the communication hole cooling body can pass, discharge pores, and continues into the outer space, and the cooling body is transported holes passable is formed, communicating the communication hole, the exhaust hole and conveying hole A buffer chamber that forms a buffer space, and
Opening and closing means comprising a shutter capable of opening and closing the transport hole;
A conveying means for carrying the cooling body into the accommodating space through the communication hole and the conveying hole, and carrying the cooling body out of the accommodating space;
Is accommodated in the buffer space, seen including a gas jetting unit for jetting the inert gas toward the cooling body being conveyed buffer space by a conveying means,
The pressure in the accommodating space and the buffer space is higher than atmospheric pressure,
From the exhaust hole, the inert gas that is supplied from the gas supply means to the accommodation space and flows into the buffer chamber through the communication hole, and the gas ejected by the gas ejection means are exhausted. A substrate manufacturing apparatus characterized by the above. A plurality of the buffer chambers;
The gas supply means supplies the inert gas to the accommodation space so that the flow rates of the inert gas flowing into the buffer spaces through the communication holes of the buffer chambers are equal to each other. The board | substrate manufacturing apparatus of description.   3. The substrate manufacturing apparatus according to claim 1, wherein the volume of the buffer chamber is selected to be greater than 0% and not greater than 10% of the volume of the chamber.   The substrate manufacturing apparatus according to claim 1, wherein the gas ejection unit is provided in the buffer space in the vicinity of the transport hole.   The substrate manufacturing apparatus according to claim 1, wherein the opening / closing means is provided in the vicinity of the transport hole.   The substrate manufacturing apparatus according to claim 1, wherein the gas jetting unit jets an inert gas toward the exhaust hole.   The substrate manufacturing apparatus according to claim 6, wherein the gas jetting unit jets a gas to the outside of the region in a region surrounded by a virtual plane extending an inner peripheral surface facing the transfer hole. The gas jetting means is formed to extend in a predetermined direction perpendicular to the direction in which the inert gas is jetted, and has a jet hole through which the inert gas is jetted.
The width dimension of the ejection hole in the direction in which the gas is ejected and the direction perpendicular to the predetermined direction is selected to be 0.05 mm or more and less than 0.2 mm. The board manufacturing apparatus according to one.   The substrate manufacturing apparatus according to claim 1, wherein the inert gas ejected from the gas ejection means is selected as at least one of a rare gas and a nitrogen gas.

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