JP2013089693A - Slice stand and manufacturing method of semiconductor wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slice stand, in which the amount of impurities mixed into a sludge produced by a fixed abrasive grain system is extremely small, with a lower cost without impairing the cutting properties, and to provide a manufacturing method of a semiconductor wafer using the slice stand.SOLUTION: A slice stand 1 which fixes a semiconductor block 2 when it is cut is provided, at least on the fixing side of the semiconductor block 2, with a member obtained by cutting out a disposal part of a semiconductor ingot composed of the same kind of semiconductor material as that of the semiconductor block 2.

Description

  The present invention relates to a slicing base for fixing a semiconductor block when the semiconductor block is cut into a wafer, and a method for manufacturing a semiconductor wafer using the slicing base.

  The manufacturing process of a semiconductor wafer includes a process of forming a wafer by slicing a semiconductor block. In this process, a wire saw device using a wire is generally used.

  The slicing method using a wire saw device includes a free abrasive grain method and a fixed abrasive grain method. The former is a method of slicing the surface with a brass-plated iron wire while supplying a slurry obtained by mixing abrasive grains such as GC (green silicon carbide) into oily or water-soluble oil or the like to the cutting site. The latter is a method of slicing while supplying oily or aqueous oil (coolant) or water using a wire (fixed abrasive wire) in which abrasive grains such as diamond particles are fixed to the surface by electrodeposition or the like. .

  The semiconductor block is cut by these methods by bonding and fixing the semiconductor block to a base called a slice base. In the loose abrasive method, it is common to use a glass slicing table. On the other hand, when a glass slicing table is used with a fixed abrasive method with a cutting force greater than that of the loose abrasive method, due to the difference in severability between the semiconductor block and the slicing table, the wafer cut-off portion, that is, the semiconductor block slicing table, The processing characteristics of the bonded portion are remarkably poor, and there is a risk of wire breakage and the like. Therefore, in the fixed abrasive method, it is common to use a slice table made of carbon or resin that is softer than the glass described in Patent Document 1 and Patent Document 2. In addition, as other materials used for the slicing table, Patent Document 1 includes a silicon single crystal, silicon polycrystal, and the like, and Patent Document 2 includes the same material as the material to be cut.

JP 2005-297156 A JP 2004-335531 A

  The slurry and coolant collected after slicing contain sliced semiconductor block slice waste, which is called sludge. Since the sludge generated by the loose abrasive method contains SiC, which is a loose abrasive, industrial waste treatment is required. Moreover, since wear of an iron wire arises with a cutting | disconnection, many metal impurities, such as iron and a plating component, are also contained. On the other hand, the sludge produced by the fixed abrasive method has almost no mixing of abrasive grains, and the amount of metal impurities in the wire material is very small because the wire is not worn by the abrasive grains. For this reason, the present inventors recycled semiconductor slice waste contained in sludge generated by the fixed abrasive method as a raw material for manufacturing a new semiconductor ingot, and manufactured a semiconductor ingot at a lower cost. Tried.

  However, according to the study by the present inventors, the sludge generated by the fixed abrasive method using the carbon slice table is sufficiently mixed with abrasive particles and metal impurities, but the carbon powder is 2 to 5%. It was found to be included. When cutting the semiconductor block, the wire will bend slightly during cutting, so even if the wire reaches the bonding surface with the slicing base in part of the semiconductor block, it does not reach other parts. There may not be. Therefore, complete cutting of the semiconductor block is ensured by cutting the wire to 5-8 mm on the surface of the slicing base. The carbon impurities contained in the sludge are considered to originate from the carbon slice table. For this reason, it has been difficult to use this sludge as a raw material for semiconductor ingots.

  Even in the fixed abrasive method, if the slicing table is made of glass, the problem of carbon impurity contamination is eliminated, but as described above, there is a problem in wafer cutting performance. In addition, Patent Document 1 and Patent Document 2 do not consider at all that sludge is used as a raw material for a semiconductor ingot, and the material of the slice table described in these documents is generally expensive, In the first place, it is meaningless to use sludge as a raw material.

  Accordingly, the present invention provides a slicing base with a very small amount of impurities mixed in sludge produced by the fixed abrasive method and a semiconductor wafer manufacturing method using the slicing base without impairing the cutting performance. The purpose is to do. Another object of the present invention is to provide a method for manufacturing a semiconductor ingot that can manufacture a semiconductor ingot at a lower cost by using a sludge or a slice table as a part of the raw material.

  As a result of intensive studies by the present inventors in order to achieve the above object, the inventors have come up with the idea that the waste material generated when a semiconductor block is cut out from a semiconductor ingot is used as a slicing base. If a semiconductor material of the same type as the semiconductor block to be cut is used for the slicing stage and the fixed abrasive method is used for cutting, the level of impurity contamination in the sludge can be reduced, and sludge can be used as a raw material for semiconductor ingots to be newly manufactured. it can. At that time, by utilizing the waste material for the slicing table, the cost is not increased due to the reuse of the sludge, and the reuse is significant. This invention is based on said knowledge and examination, The summary structure is as follows.

(1) A slicing base for fixing the semiconductor block when cutting the semiconductor block,
A slicing base comprising a member obtained by cutting out a discarded portion of a semiconductor ingot made of the same kind of semiconductor material as that of the semiconductor block, at least on the side on which the semiconductor block is fixed.
(2) The slice table according to (1), wherein the member is a member cut out from a top portion or a tail portion of the semiconductor ingot.
(3) The slicing table according to (2), wherein the semiconductor ingot is manufactured by an electromagnetic casting method.
(4) The slicing table according to (2) or (3), which includes only the member.
(5) The slicing table according to (1), wherein the member is a member obtained by cutting a side surface of the semiconductor ingot manufactured by an electromagnetic casting method.
(6) The slicing table according to (5), wherein a resin layer is provided on the side surface of the member.
(7) Until the semiconductor block is fixed to the slicing base according to any one of the above (1) to (6) and reaching a position where a fixed abrasive wire saw is cut from the semiconductor block into at least the surface of the slicing base A method of manufacturing a semiconductor wafer, comprising a step of moving and cutting the semiconductor block to form a semiconductor wafer.
(8) A method for manufacturing a semiconductor ingot according to (7), wherein the semiconductor ingot is manufactured using sludge generated during the step as at least a part of a raw material for manufacturing the semiconductor ingot. Method.
(9) A method for producing a semiconductor ingot, characterized in that a semiconductor ingot is produced by using the slicing table used in the method for producing a semiconductor wafer as described in (7) above as at least a part of a raw material for producing a semiconductor ingot.
(10) A method for producing a solar cell wafer, comprising slicing a semiconductor ingot obtained by the production method according to (8) or (9) to produce a solar cell wafer.
(11) A method for producing a solar battery cell, comprising producing a solar battery cell using a solar battery wafer obtained by the production method according to (10) above.
(12) A method for producing a solar cell module, comprising producing a solar cell module from solar cells obtained by the production method according to (11) above.

  According to the present invention, there is provided a slicing pedestal with a very small amount of impurities mixed in sludge produced by the fixed abrasive method and a semiconductor wafer manufacturing method using the slicing pedestal without impairing the cutting performance. can do. Further, a semiconductor ingot can be manufactured at a lower cost by using a sludge or a slice table as a part of the raw material.

(A) is a schematic diagram which shows the state which cut | disconnects the semiconductor ingot 2 with a fixed abrasive multi-wire saw apparatus using the slice stand 1 according to this invention, (b) and (c) are fixed abrasive wire It is a schematic diagram which shows the state which has reached to the position which 4 cuts into the slice stand 1. FIG. (A)-(e) is a schematic diagram explaining an example of the cutting method which cuts out the semiconductor ingot used when manufacturing the slice stand according to this invention, and divides | segments into a semiconductor block and a discard part. It is a schematic cross section of an example of the electromagnetic casting apparatus used for the electromagnetic casting method. It is a schematic cross section for demonstrating the manufacturing method of another slice stand 601 according to this invention.

  Hereinafter, the present invention will be described in more detail with reference to the drawings.

(Slice table and semiconductor wafer manufacturing method using this slice table)
As shown in FIG. 1, the slicing base 1 according to an embodiment of the present invention fixes the semiconductor block 2 when the semiconductor block 2 is cut. The semiconductor block 2 is bonded and fixed to the slicing base 1 with an epoxy-based adhesive, and the slicing base 1 is bonded and held to the work plate 3 with an epoxy-based adhesive, and the work plate is attached to the wire saw body (not shown). Fix 3 with screws. Then, the semiconductor block 2 can be sliced perpendicularly to the casting direction with a fixed abrasive wire saw 4 operated by a roller 5 to obtain a semiconductor wafer. Here, in order to ensure the reliable cutting of the semiconductor block 2, the fixed abrasive wire saw 4 is moved to the semiconductor block 2 until reaching the position where the slice base 1 is cut by 5 to 8 mm in consideration of the bending of the fixed abrasive wire saw 4. Relative movement (FIGS. 1B and 1C).

  The characteristic configuration of the slicing base of the present invention is that at least a side where the semiconductor block 2 is fixed has a member obtained by cutting out a semiconductor block 2, that is, a discarded portion of a semiconductor ingot made of the same kind of semiconductor material as that to be cut. And the slice stand 1 of this embodiment consists only of the member which cut out the said discard part.

  In this specification, a portion cut out from a semiconductor ingot and formed into a semiconductor wafer by slicing is referred to as a “semiconductor block”, and a portion cut out from the semiconductor ingot and thereafter not processed into a wafer is referred to as a “discarded portion”.

  As the discard part to be the slice table 1, a discard part obtained from a semiconductor ingot obtained by cutting the semiconductor block 2 to be cut by the slice table may be used. Further, instead of the semiconductor block 2 itself to be cut, a discarded portion obtained from the same type of semiconductor ingot as the semiconductor block 2 to be cut may be used.

  Hereinafter, the technical significance of adopting the above features of the present invention will be described with specific examples together with the effects. Conventionally, sludge mixed with carbon powder generated from a carbon slice base cannot be used as a raw material for a new semiconductor ingot. A slice base made of the same semiconductor material as the semiconductor block to be sliced can be used as a raw material for a semiconductor ingot because the sludge contains little impurities such as carbon. However, it is generally impractical to produce a slicing stand from such a semiconductor material because of its high cost. Therefore, the present inventor can use a discarded portion of the semiconductor ingot as a material for the slicing table, and at a lower cost, without damaging the cutting performance, the slicing table with a very small amount of impurities mixed into the sludge generated by the fixed abrasive method. And it discovered that the manufacturing method of the semiconductor wafer using this slice stand could be provided, and came to complete this invention. As a result, by using the slicing table of the present invention, sludge produced when the semiconductor ingot is cut by the fixed abrasive method, and the slicing table of the present invention itself as a part of the raw material, a semiconductor ingot is manufactured at a lower cost. Is possible.

  Cutting of the semiconductor block 2 using the slicing base 1 according to an embodiment of the present invention is performed by a fixed abrasive wire saw. This is because the sludge generated by the loose abrasive method contains abrasive grains such as SiC, and it is difficult to use as a raw material for manufacturing a new semiconductor ingot.

  A semiconductor ingot for obtaining a waste portion for making the slice base 1 of the present embodiment can be grown by any casting method such as the Czochralski method, the casting method, or the electromagnetic casting method. In general, in a casting method such as a casting method in which a silicon raw material is melted in a square crucible and solidified as it is, a portion of the semiconductor ingot near the bottom, top, and side portions of the crucible has impurities and resistance. It is not a wafer from the viewpoint. In addition, in casting methods having a casting direction, such as the Czochralski method and electromagnetic casting method with lifting and lowering operations, the top portion obtained at the beginning of casting, the tail portion obtained at the end of casting, and the surface of the semiconductor ingot are uneven. The ingot side surface, which is a rough casting surface, becomes a waste part.

  An example of a cutting method for separating the semiconductor block and the discarded portion from the semiconductor ingot will be described with reference to FIG. First, the semiconductor ingot 10 cast into a rectangular tube shape is divided into a top portion 30 and a tail portion 50 at both ends in the casting direction of the ingot, and a plurality of body portions 40 sandwiched between the top portion 30 and the tail portion 50. (FIG. 2A). The top portion 30 and the tail portion 50 are members that have not been subjected to wafer processing in terms of resistivity, crystal quality, and the like and are conventionally discarded. As shown in FIGS. 2B and 2C, each body portion 40 first cuts out a member 60 including two opposing casting surfaces and further divides it into two. Thereafter, as shown in FIG. 2D, the member 70 including the facing casting surface is cut out from each of the two divided blocks, and is divided into three semiconductor blocks 20. Thus, two large members 60 cut out from the side surfaces, four small members 70 cut out from the side surfaces, and six semiconductor blocks 20 are obtained from each body portion 40 (FIG. 2E). ). The members 60 and 70 cut out from the side surfaces have a chill layer with a small particle size and a large number of crystal defects, and thus are conventionally discarded portions.

  It is preferable that the member cut out from the waste portion used for the slicing base 1 is a member cut out from the top portion 30 or the tail portion 50 of the semiconductor ingot 10. Since the top part 30 or the tail part 50 is a large semiconductor lump, the slice stage can be efficiently cut out, and the slice stage can be manufactured at low cost. In addition, sludge generated through slicing can be used as a raw material for a new semiconductor ingot even if shavings on the slicing table are mixed.

  It is preferable that the shape of the semiconductor ingot 10 for obtaining the waste portion for obtaining the slice base 1 of the present embodiment is a rectangular tube shape. The top part 30, tail part 50, and members 60 and 70 obtained by cutting out the surface of the side part obtained from the rectangular tube-shaped ingot produce a slicing base corresponding to the shape of the semiconductor block as compared with that obtained from the cylindrical ingot. This is because it is easy to do. In that respect, since a rectangular tube-shaped ingot can be produced by the electromagnetic casting method, it is preferable to use the discarded portion of the semiconductor ingot produced by the electromagnetic casting method as the slice base 1.

  Here, the electromagnetic casting method is a method of casting while pulling down a semiconductor material melted by electromagnetic induction heating inside a large furnace, and a semiconductor ingot can be cast with almost no molten semiconductor material contacting the mold. . FIG. 3 is a cross-sectional view schematically showing an example of an electromagnetic casting apparatus used in the electromagnetic casting method. As shown in FIG. 3, the chamber 101 is a double-walled cooling container so as to be protected from internal heat generation, and a cooling mold 102, an induction coil 103, and a heater 104 are arranged at the center. . In the illustrated example, the cooling mold 102 is a copper water-cooled cylinder, and is divided into a plurality of parts in the circumferential direction except for the upper part and has no bottom. In the illustrated example, the induction coil 103 is concentrically provided on the outer peripheral side of the cooling mold 102 and is connected to a power source by a coaxial cable (not shown). In the illustrated example, the heater 104 is provided concentrically below the cooling mold 102 and heats the ingot 105 pulled down from the cooling mold 102 to give a predetermined temperature gradient in the pulling-down axis direction of the ingot 105. To cast using the apparatus shown in FIG. 3, first, the semiconductor material 106 is charged into the cooling mold 102, and then an alternating current is passed through the induction coil 103. The cooling mold 102 is divided in the circumferential direction, and the respective pieces are electrically separated from each other. Therefore, a current loop is formed in each piece, and the current generates a magnetic field in the cooling mold 102. Thereby, the semiconductor material is melted by electromagnetic induction heating, and the melt 107 of the semiconductor material is melted. Here, the semiconductor material in the cooling mold 102 receives a force inward in the radial direction of the cooling mold 102 due to the electromagnetic interaction between the magnetic field created by the inner wall of the cooling mold 102 and the current on the surface of the molten semiconductor material 107. It is melted in a state where it is difficult to contact the cooling mold 102, impurity contamination from the cooling mold 102 is prevented, and the ingot 105 can be easily pulled down.

  As in the present embodiment, it is preferable that the slicing base 1 is produced only from the above-described waste portion. This is because the contamination of the sludge can be more reliably suppressed, and the slice table 1 itself can be used as a raw material for a new semiconductor ingot without any treatment.

  In addition, as a slicing base according to another embodiment of the present invention, a member obtained by cutting out a discarded portion used for the slicing base may be a member obtained by cutting out a side surface of a semiconductor ingot manufactured by an electromagnetic casting method. Since slicing is performed perpendicularly to the casting direction of the semiconductor ingot (arrow direction in FIG. 2), a surface parallel to the casting direction of the ingot is bonded and fixed to the slicing base. Therefore, a slice table having a surface larger than the size of this surface is required. Here, it is preferable to acquire the member 70 which cut out the side surface of the ingot by the method shown in FIG. The semiconductor block 20 is obtained by cutting out a member obtained by cutting out a side surface that is a surface parallel to the casting direction from the body portion 40 (see FIG. 2). Therefore, the member 70 obtained by cutting out the side surface is appropriate as the size of the slicing base for cutting the semiconductor 20.

  Since the side surface 70a has a cast surface, there are irregularities, whereas the ingot cut surface 70b is flat. In order to ensure the function as a slicing base, that is, the function of fixing the semiconductor block, it is preferable that the ingot cut surface 70b be a surface for fixing the semiconductor block of the slicing base (see FIG. 1).

  When the member which cut out the side part surface of the semiconductor ingot manufactured by the electromagnetic casting method is used as the slicing base, the resin layer may be provided on the side part surface. As described above and as shown in FIG. 4, the members 600 obtained by cutting the side surfaces cut out from the semiconductor ingot produced by the electromagnetic casting method are not parallel to each other. When the semiconductor block is cut with a wire saw, the surface of the slicing base that fixes the semiconductor block and the surface that is fixed to the work plate must be parallel. Here, while the thickness of the member 600 cut out from the side surface is about 3 to 20 mm, the wire saw cuts about 5 to 8 mm into the slicing base, so it is not preferable to make the surfaces parallel by shaving. Therefore, as shown in FIG. 4, the resin 800 is placed on the side surface 600a of the member 600 whose side surface is cut out to provide the resin layer 801, and the surfaces of the ingot cutting surface 600b and the resin layer are parallel to each other. In this manner, the slice table 601 may be manufactured. The raw material used for this resin layer is preferably an epoxy adhesive. This is because it is resistant to chemical attack from the coolant component. However, it is preferable that the cutting of the wire saw into the slicing base does not reach the resin layer 801. Therefore, the thickness of the member 600 is more preferably 8 to 20 mm.

(Method for manufacturing semiconductor ingot)
The semiconductor block cutting process using the slicing table as described above makes it possible to obtain sludge with less impurities, so that the sludge is used as at least a part of the raw material of the new ingot to produce a new semiconductor ingot. can do.

  The slice base according to the present invention can also produce a new semiconductor ingot as part of the raw material for producing the semiconductor ingot. This is because the slicing base is also made of the same kind of semiconductor material as the new semiconductor ingot. Here, the slice base is preferably used as a raw material of the semiconductor ingot after the adhesive is removed by washing with sulfuric acid or sulfuric acid / hydrogen peroxide and subsequent washing with hydrofluoric acid. Moreover, when the slice base has a resin layer, it is preferable to further remove the resin layer.

(Manufacturing method of solar cell wafer, solar cell and solar cell module)
If a new semiconductor ingot obtained in this manner is sliced to produce a solar cell wafer, an inexpensive solar cell wafer can be obtained. Therefore, the solar cell and solar cell module produced from the solar cell wafer produced in this way are also inexpensive.

  Although the present invention has been described above, these are examples of typical embodiments, and the present invention is not limited to these embodiments, and various modifications can be made within the scope of the invention. It can be changed.

  In order to further clarify the effects of the present invention, comparative evaluations in which experiments of Examples and Comparative Examples described below were conducted will be described.

<Preparation of sample>
Example 1
First, a polycrystalline silicon ingot having a length of 505 mm × width of 345 mm × height (casting direction) of 7000 mm is manufactured by an electromagnetic casting method, and as shown in FIG. 2, the length of 156 mm × width of 156 mm × height (casting). Direction) A 400 mm silicon block was cut out. A top member having a length of 505 mm, a width of 345 mm, and a height (casting direction) of 230 mm was cut into a length of 400 mm, a width of 156 mm, and a height (casting direction) of 15 mm to prepare a slice table. On the slice table, a polycrystalline silicon block was bonded and fixed to one surface having a size of 400 mm × 156 mm with an epoxy adhesive, and a work plate was bonded and fixed to the rear surface with an epoxy adhesive. Next, while supplying the coolant whose main component is glycol with a fixed abrasive wire saw (wire material: iron, plating material: nickel) with a diamond abrasive grain type and an ingot cutting speed of 0.6 mm / min. The slicing of the polycrystalline silicon block was performed so as to cut to a depth of 161 to 163 mm from the surface of the silicon block so that 5 to 8 mm was cut into the slicing stage.

(Example 2)
In a member obtained by cutting a side surface of a cut surface of 156 mm × 400 mm and a thickness of 10 mm to 12 mm obtained from the same polycrystalline silicon ingot as in Example 1, a resin layer made of an epoxy adhesive is formed on the surface having a casting surface. The slice table was used. The resin layer was flattened by cutting. The silicon block is sliced under the same conditions as in Example 1 except that the polycrystalline silicon block to be cut is bonded and fixed to the cutting surface on the member side of the slicing base, and the surface of the resin layer is bonded and fixed to the work plate. went.

(Comparative example)
The silicon block was sliced under the same conditions as in Example 1 except that a carbon slice base (manufactured by Mechanical Carbon Industry Co., Ltd.) was used.

(Evaluation of sludge impurities)
The carbon content in the sludge produced in the examples and comparative examples was measured. The measurement was performed by calculating the volume of carbon contained in the sludge from the cutting depth of the slicing base and the width of the cutting line. As a result, in the comparative example, the carbon content in the sludge was 4% by volume. In Examples 1 and 2, since the slice table does not contain carbon, the carbon content in the sludge is 0% by volume.

  Moreover, when the sludge of the comparative example was washed with a 1: 1 mixed solution of hydrofluoric acid and nitric acid, black dirt derived from carbon adhered to the washing container. On the other hand, in the sludges of Examples 1 and 2, there was no such black stain.

  Furthermore, when the casting method was performed using a small cast casting tester (manufactured by Noritake TCF, a small melting test furnace), the sludges of Examples 1 and 2 were completely dissolved after removal of the coolant and metal impurities. I was able to. On the other hand, even after removing the coolant and metal impurities, the sludge of the comparative example could not be completely dissolved due to the problem of the solid solubility limit.

(Evaluation of wafer sliced using silicon slice table)
About the slice quality of the wafer manufactured in the example or the comparative example, using HENEKE (Hennecke, HE-WI-04), the average thickness of the wafer, the TTV indicating the unevenness of the wafer unevenness, and the stripe of 15 μm depth The flatness was evaluated from saw1 indicating the existence probability. As a result, it was found that the flatness of Examples 1 and 2 is equivalent to the flatness of the comparative example, which is a conventional product, and that the examples satisfy the product standards.

  According to the present invention, there is provided a slicing pedestal with a very small amount of impurities mixed in sludge produced by the fixed abrasive method and a semiconductor wafer manufacturing method using the slicing pedestal without impairing the cutting performance. can do. Further, a semiconductor ingot can be manufactured at a lower cost by using a sludge or a slice table as a part of the raw material.

DESCRIPTION OF SYMBOLS 1 Slice stand 2 Semiconductor block 3 Workplate 4 Fixed abrasive wire saw 5 Roller 10 Semiconductor ingot 20 Semiconductor block 30 Top part 40 Body part 50 Tail part 60 The member which cut out the side part surface 70 The member which cut out the side part surface 70a side Part surface (cast surface)
70b Ingot cutting surface 101 Chamber 102 Cooling mold 103 Inductive coil 104 Heater 105 Ingot 106 Semiconductor material 107 Molten semiconductor material 600 Member cut out from side surface 600a Side surface (cast surface)
600b Ingot cutting surface 601 Slicing base 800 Resin 801 Resin layer

Claims (12)

A slicing base for fixing the semiconductor block when cutting the semiconductor block,
A slicing base comprising a member obtained by cutting out a discarded portion of a semiconductor ingot made of the same kind of semiconductor material as that of the semiconductor block, at least on the side on which the semiconductor block is fixed.   The slice table according to claim 1, wherein the member is a member cut out from a top portion or a tail portion of the semiconductor ingot.   The slice table according to claim 2, wherein the semiconductor ingot is manufactured by an electromagnetic casting method.   The slice table according to claim 2 or 3, comprising only the member.   The slicing table according to claim 1, wherein the member is a member obtained by cutting a side surface of the semiconductor ingot manufactured by an electromagnetic casting method.   The slicing table according to claim 5, further comprising a resin layer on the side surface of the member.   A semiconductor block is fixed to the slicing base according to any one of claims 1 to 6, and a fixed abrasive wire saw is moved from the semiconductor block to at least a position to be cut into the surface of the slicing base, A method for producing a semiconductor wafer, comprising a step of cutting a semiconductor block into a semiconductor wafer.   8. The method of manufacturing a semiconductor ingot according to claim 7, wherein the semiconductor ingot is manufactured using sludge generated during the process as at least a part of a raw material for manufacturing the semiconductor ingot.   A method for manufacturing a semiconductor ingot, wherein the semiconductor ingot is manufactured by using the slicing table used in the method for manufacturing a semiconductor wafer according to claim 7 as at least a part of a raw material for manufacturing the semiconductor ingot.   A method for producing a solar cell wafer, comprising: slicing a semiconductor ingot obtained by the production method according to claim 8 or 9 to produce a solar cell wafer.   The manufacturing method of a photovoltaic cell characterized by producing a photovoltaic cell with the wafer for solar cells obtained by the manufacturing method of Claim 10. The manufacturing method of a solar cell module characterized by producing a solar cell module from the photovoltaic cell obtained by the manufacturing method of Claim 11.

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