WO2014119816A1

WO2014119816A1 - Wire cleaning apparatus, and wire sawing apparatus and method using the same

Info

Publication number: WO2014119816A1
Application number: PCT/KR2013/001476
Authority: WO
Inventors: Ji Won Jeon; Soon Hyun Gong
Original assignee: Lg Siltron Incorporated
Priority date: 2013-01-29
Filing date: 2013-02-25
Publication date: 2014-08-07
Also published as: KR101379801B1

Abstract

Disclosed is a wire cleaning apparatus including a first nozzle configured to discharge a fluid on a first direction, and a tubular member located in a movement path of a wire that is moved in a second direction different from the first direction after contaminated by slurry, the tubular member having an inner surface provided with a spiral guiding portion and serving to clean the wire using the fluid discharged from the first nozzle on the movement path.

Description

WIRE CLEANING APPARATUS, AND WIRE SAWING APPARATUS AND METHOD USING THE SAME

The present invention relates to a wire cleaning apparatus, and a wire sawing apparatus and method using the same.

Silicon wafers, which are used as materials for production of electronic elements or solar cells, are fabricated through several operations including a slicing process of slicing a mono-crystal silicon ingot into thin wafers, a lapping process of polishing a wafer to a desired thickness to improve flatness, an etching process of removing an internal damaged layer of a wafer, a polishing process of improving mirror surface grinding and flatness, and a cleaning process of removing contaminants from a wafer surface.

In the aforementioned slicing process, the ingot is cut into a thin wafer form using a wire and slurry.

FIG. 1 schematically illustrates a block diagram of a conventional wafer sawing apparatus for fabrication of a wafer for a solar cell.

The conventional wire sawing apparatus illustrated in FIG. 1 consists of a main sawing chamber 10, a wire bobbin chamber 20, an oil ejection nozzle 30, an oil pump 50, and an oil tank 52.

The main sawing chamber 10 includes a slurry ejection nozzle 12 and a main work roller 14. The wire bobbin chamber 20 includes a sawing steel wire 22A, a wire guide pulley 24, a bobbin 26 for supply of a new wire, and a bobbin 28 for collection of a used wire.

In the conventional wire sawing apparatus having the above described configuration, as the nozzle 12 ejects slurry that serves as a blade to the wire 22A that is moving at a high speed, sawing of an ingot 5 is achieved. In this case, a used wire 22B stained with the slurry is wound around the bobbin 28. The above described sawing procedure, however, may cause the slurry to be scattered in all directions within the wire bobbin chamber 20, necessitating frequent replacement of a variety of consumables. To prevent this problem, oil is supplied from the oil tank 52 to the oil ejection nozzle 30 through the oil pump 50, and the oil ejection nozzle 30 ejects a curtain of oil 40 to realize cleaning of the wire 22B.

However, cleaning the wire 22B using the oil as described above causes several problems, such as the possibility of secondary contamination of the wire 22B by the oil, increased fabrication costs and difficulty in management due to the necessity of

separate devices

30, 50 and 52, and a limit in the cleaning of the wire 22B that travels at a high speed of 900 m/min because the slurry in itself that is to be removed from the wire 22B is oil.

An objective of the present invention is to provide a wire cleaning apparatus capable of efficiently cleaning a wire contaminated by slurry in a simplified manner.

Another objective of the present invention is to provide a wire sawing apparatus and method using a wire cleaning apparatus.

The objective of the present invention can be achieved by providing a wire cleaning apparatus including a first nozzle configured to discharge a fluid in a first direction, and a tubular member located on a movement path of a wire that is moved in a second direction different from the first direction after contaminated by slurry, the tubular member having an inner surface provided with a spiral guiding portion and serving to clean the wire using the fluid discharged from the first nozzle on the movement path.

The tubular member may include a first end having a first opening into which the wire is introduced, the first end providing an exit of the fluid having been used to clean the wire, and a second end having a second opening into which the fluid discharged from the first nozzle is introduced, the second end providing an exit of the wire having passed through the tubular member. An outlet of the first nozzle from which the fluid is discharged may be located to face the second end. A diameter of the first opening may be different from a diameter of the second opening. The diameter of the first opening may be less than the diameter of the second opening.

The tubular member may have a funnel shape, or may take the form of a venturi tube having a middle portion, a diameter of which is less than those of the first and second ends. In the tubular member taking the form of a venturi tube, a distance from the middle portion to the first end may be less than a distance from the middle portion to the second end.

The spiral guiding portion may include a spiral groove, or a spiral ridge. Pitches of the spiral guiding portion may be gradually reduced from the second end to the first end.

The wire cleaning apparatus may further include a fluid container configured to accommodate the fluid, and a first temperature regulator configured to regulate a temperature of the fluid supplied from the fluid container and supply the fluid into the first nozzle. The first temperature regulator may regulate the temperature of the fluid within a range of 10℃ to 20℃.

The wire cleaning apparatus may further include a heater located around the tubular member to heat the tubular member. The wire cleaning apparatus may further include a second temperature regulator configured to control a temperature of the heater. The second temperature regulator may control heating of the heater such that the temperature of the fluid is within a range of 10℃ to 20℃.

The wire cleaning apparatus may further include a rotation driving unit configured to rotate the tubular member in a direction of accelerating a flow of the fluid passing through the tubular member.

The wire cleaning apparatus may further include a slurry container in which the slurry carried by the fluid having been used to clean the wire is accommodated, a filter configured to filter the slurry accommodated in the slurry container, and a second nozzle configured to eject the filtered slurry to another movement path of the cleaned wire.

In accordance with another aspect of the present invention, there is provided a wire sawing apparatus including the wire cleaning apparatus according to any one of claims 1 to 18, wherein the wire sawing apparatus performs sawing of an ingot by the wire contacting the slurry.

The wire sawing apparatus may further include an ingot holder configured to hold the ingot, a first wire bobbin, around which a wire cleaned by the wire cleaning apparatus is wound, a second wire bobbin, around which a wire to be used to saw the ingot is wound, a first touch roller configured to control constant-speed winding of the cleaned wire around the first wire bobbin, and a second touch roller configured to control constant-speed unwinding of the wire from the second wire bobbin.

The wire wound around the second wire bobbin may be the cleaned wire.

The wire may be moved in a single direction, or in both directions.

In accordance with a further aspect of the present invention, there is provided a wire sawing method including sawing an ingot by ejecting slurry to a wire, discharging a fluid in a first direction, and cleaning the wire by passing the fluid in the first direction through the interior of a tubular member, wherein the tubular member is located in a movement path of the wire that is moved in a second direction different from the first direction after coming into contact with the slurry, and the tubular member has an inner surface provided with a spiral guiding portion.

The wire sawing method may further include accommodating the slurry carried by the fluid having been used to clean the wire, filtering the accommodated slurry, and ejecting the filtered slurry to another movement path of the cleaned wire to reuse the filtered slurry for sawing of the ingot.

With a wire cleaning apparatus, and a wire sawing apparatus and method using the same according to the embodiments of the present invention, a wire is cleaned by a fluid passing through a tubular member, and the fluid swirls and passes through the tubular member at a high speed so as to clean the wire throughout a range of 360 degrees owing to a spiral guiding portion formed at an inner surface of the tubular member, which may ensure more efficient cleaning of the wire and reduce cleaning costs because an additional cleaning nozzle is unnecessary. The spiral guiding portion is configured such that pitches thereof are gradually reduced toward a first end of the tubular member from which the fluid is discharged, to allow the fluid to pass through the tubular member at an increased speed, thereby facilitating cleaning ability of the wire. The tubular member taking the form of a venturi tube may ensure that slurry resulting from the cleaning of the wire is discharged from the tubular member at a low speed without being scattered, thereby preventing an equipment from be contaminated. The surface quality of the cleaned wire may be improved as a result of regulating the temperature of the fluid to evaporate and remove even a small amount of slurry staining the wire. Cleaning of the wire may further be facilitated by rotating the tubular member in the same direction as a flow direction of the fluid so as to increase the flow speed of the fluid. The slurry collected in a slurry container and the cleaned wire may be recycled for ingot sawing, thereby reducing ingot sawing costs. Also, by allowing the cleaned wire, rather than the contaminated wire, to be wound around a bobbin, it is possible to prevent equipment contamination.

The accompanying drawings, which are included to provide a further understanding of the invention, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention.

In the drawings:

FIG. 1 is a block diagram diagrammatically illustrating a conventional wire sawing apparatus for fabrication of a wafer for a solar cell;

FIG. 2 is a perspective view illustrating a wire cleaning apparatus according to an embodiment of the present invention;

FIG. 3a is a sectional view taken along the line 3-3’ of FIG. 2, illustrating an internal configuration of a cut tubular member;

FIG. 3b is a view illustrating an internal configuration of the tubular member when viewed from a first direction;

FIGs. 4a and 4b are sectional views taken along the line 4-4’ of FIG. 3;

FIG. 5 is a view embodying a flow of fluid introduced into the tubular member of the wire cleaning apparatus illustrated in FIG. 2;

FIG. 6 is a perspective view of a wire cleaning apparatus according to another embodiment of the present invention;

FIG. 7 is a perspective view of a wire cleaning apparatus according to still another embodiment of the present invention;

FIG. 8 is a perspective view of a wire cleaning apparatus according to still another embodiment of the present invention;

FIG. 9 is a block diagram of a wire sawing apparatus according to an embodiment of the present invention; and

FIG. 10 is a flowchart explaining a wire sawing method according to an embodiment of the present invention, which is performed by the wire sawing apparatus illustrated in FIG. 9.

For a better understanding of the present invention, reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The present invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be through and complete and will fully convey the scope to those skilled in the art.

FIG. 2 is a perspective view illustrating a wire cleaning apparatus 100A according to an embodiment of the present invention.

The wire cleaning apparatus 100A illustrated in FIG. 2 includes a first nozzle 120 and a tubular member 130A.

The first nozzle 120 is configured to discharge a fluid 122 in a first direction 124. Here, the fluid 122 may be liquid or gas, such as air, but is not limited thereto.

The tubular member 130A is arranged on a first movement path of a wire 110A. Here, the first movement path refers to a path along which the wire 110A, contaminated by slurry, etc., is moved. Also, a second movement path refers to a path along which a cleaned wire 110B is moved. The wire 110A is a wire contaminated by slurry after coming into contact with the slurry, and is moved in a second direction 112 that is different from the first direction 124. Here, the first direction 124 and the second direction 112 may be opposite to each other. The tubular member 130A serves to clean the wire 110A using the fluid 122 discharged from the first nozzle 120 in the first movement path of the wire 110A.

The tubular member 130A has first and second ends 132 and 134. The wire 110A moved in the first direction 112 is introduced into the first end 132. The first end 132 is provided with a first opening 133 that provides an exit of the fluid used to clean the wire 110A. The fluid 122 discharged from the first nozzle 120 is introduced into the second end 134. The second end 134 is provided with a second opening 135 that provides an exit of the cleaned wire 110B having passed through the tubular member 130A.

To ensure that the fluid 122 discharged from the first nozzle 120 is introduced into the tubular member 130A, an outlet 121 of the first nozzle 120, from which the fluid 122 is discharged, may be located to face the second end 134 of the tubular member 130A.

In this case, diameters of the first opening 133 and the second opening 135 of the tubular member 130A are different from each other. The diameter of the first opening 133 may be less than the diameter of the second opening 135, and the tubular member 130A may have a funnel shape. While the fluid 122 is discharged from the tubular member 130A, shaking of the wire 110B may occur due to the flow speed of the fluid 122 so that the wire 110B may collide with the second end 134 of the tubular member 130A. Accordingly, to prevent the collision between the wire 110B and the second end 134 of the tubular member 130A, the diameter of the second opening 135 may be greater than the diameter of the first opening 133.

By allowing the fluid 122 to pass through the interior of the tubular member 130A, slurry (or sludge) staining the wire 110A may be easily removed by the fluid 122 within the tubular member 130A.

Additionally, a spiral guiding portion 136 may be formed at an inner surface of the tubular member 130A.

FIG. 3a is a sectional view taken along the line 3-3’ of FIG. 2, illustrating an internal configuration of the cut tubular member 130A, FIG. 3b is a view illustrating an internal configuration of the tubular member 130A when viewed from the first direction 124, and FIGs. 4a and 4b are sectional views taken along the line 4-4’ of FIG. 3a.

Referring to FIGs. 3a and 3b, the spiral guiding portion 136 is formed at an inner surface of a body 131 of the tubular member 130A. The spiral guiding portion 136 may have a symmetrical shape on the basis of a wire 110. The spiral guiding portion 136 may take the form of a spiral groove 136A as illustrated in FIG. 4a, or may take the form of a spiral ridge 136B as illustrated in FIG. 4b.

Pitches of the spiral guiding portion 136 may be gradually reduced from the second end 134 to the first end 132. Namely, as illustrated in FIG. 3a, pitches d1 to d6 may be represented by d1 > d2 > d3 > d4 > d5 > d6. When the pitches are reduced toward the first end 132 from which the fluid 122 is discharged, this assists the fluid 122 introduced into the tubular member 130A in passing through the tubular member 130A at a greater speed, thereby improving cleaning ability of slurry staining the wire 110A.

FIG. 5 is a view embodying a flow 126 of the fluid 122 introduced into the tubular member 130A of the wire cleaning apparatus 100A illustrated in FIG. 2.

Referring to FIGs. 2 and 5, the fluid 122, which has been discharged from the first nozzle 120 in the first direction 124 and introduced into the tubular member 130A through the second opening 135 of the second end 134,swirlsaboutthewire110Aasdesignatedbyanarrow126,therebyflowingtothefirstend132. In this case, owing to the spiral guiding portion 136 formed at the inner surface of the tubular member 130A, the fluid 122 passes in a spiral trajectory through the tubular member 130A at a high speed, thereby ensuring easier cleaning of the slurry staining the wire 110A.

Also, as the fluid 122 supplied from the first nozzle 120 passes in a spiral trajectory through the interior of the tubular member 130A at a high speed owing to the presence of the spiral guiding portion 136, cleaning of the wire 110A throughout a range of 360 degrees is possible. This eliminates the need for an additional cleaning nozzle because the single first nozzle 120 is sufficient. As such, the wire cleaning apparatus 100A of the present embodiment may perform simplified cleaning of the wire 110A using the single nozzle 120, that results in reduced cleaning costs.

FIG. 6 is a perspective view of a wire cleaning apparatus 100B according to another embodiment of the present invention.

While the wire cleaning apparatus 100A illustrated in FIG. 2 includes the funnel shaped tubular member 130A, the wire cleaning apparatus 100B illustrated in FIG. 6 includes a tubular member 130B in the form of a venturi tube having a middle portion 138, which has a small diameter than those of the first and second ends 132 and 134. Except for this, the wire cleaning apparatus 100B illustrated in FIG. 6 is identical to the wire cleaning apparatus 100A illustrated in FIG. 2, and thus a detailed description of the same parts will be omitted.

The tubular member 130B illustrated in FIG. 6 may be divided into a first segment S1 and a second segment S2 on the basis of the middle portion 138. The first segment S1, as described above, is a portion where the spiral guiding portion 136 is located. The wire 110A is cleaned by the fluid 122 in the first segment S1. The second segment S2 is a portion defining an exit through which the fluid 122 having been used to clean the wire 110A is discharged from the first end 132. In this case, a length L2 from the middle portion 138 to the first end 132 is less than a length L1 from the middle portion 138 to the second end 134.

Bernoulli’s principle states that the speed of a fluid is increased when passing through a narrow passage and is reduced when passing through a wide passage. Increase in the speed of a fluid causes reduction in pressure, whereas reduction in the speed of a fluid causes increase in pressure. Thus, in the tubular member 130B illustrated in FIG. 6, the speed of the fluid 122 is increased when the fluid 122 passes through the narrow passage 138, and is reduced when passing through wide spaces S1 and S2.

Therefore, the speed of the fluid 122 passing through the first end 132 of the tubular member 130B illustrated in FIG.6 is less than the speed of the fluid 122 passing through the first end 132 of the tubular member 130A illustrated in FIG.2. For this reason, the slurry carried by the fluid 122 having been used to clean the wire 110A may be discharged at a low speed through the first end 132, that may prevent scattering of the slurry 180 discharged from the first end 132. Consequently, it is possible to prevent contamination of equipment (for example, 170 and 172) due to scattering of the discharged slurry 180.

Referring to FIGs. 2, 5 and 6, the wire cleaning apparatus 100A; 100B may further include a fluid container 140 and a first temperature regulator 142.

The fluid container 140 accommodates a fluid and supplies the accommodated fluid to the first temperature regulator 142. The first temperature regulator 142 regulates a temperature of the fluid supplied from the fluid container 140 and provides the fluid 122 having the regulated temperature to the first nozzle 120. The first temperature regulator 142 may regulate the temperature of the fluid within a range of 10℃ to 20℃.

FIG. 7 is a perspective view of a wire cleaning apparatus 100C according to still another embodiment of the present invention.

Unlike the wire cleaning apparatus 100A illustrated in FIG. 2, the wire cleaning apparatus 100C illustrated in FIG. 7 may further include a heater 150 and a second temperature regulator 152. Except for this, the wire cleaning apparatus 100C illustrated in FIG. 7 is identical to the wire cleaning apparatus 100A illustrated in FIG. 2, and thus a detailed description of the same parts will be omitted.

The heater 150 is located around the tubular member 130A, and serves to heat the tubular member 130A. As illustrated in FIG. 7, the heater 150 may be located at a part of an outer wall of the tubular member 130A, and may be configured to surround the tubular member 130A, although the present embodiment is not limited thereto.

The second temperature regulator 152 controls a temperature of the heater 150. For example, the second temperature regulator 152 may control heating of the heater 150 such that the temperature of the fluid 122 passing through the tubular member 130A is within a range of 10℃ to 20℃.

When cleaning the contaminated wire 110A using the fluid 122, the temperature of which has been adjusted by the above described respective first and

second temperature regulators

142 and 152, even a small amount of slurry staining the wire 110A may be evaporated and removed within the tubular member 130A; 130B. Consequently, the cleaned wire 110B may achieve an improved surface quality.

FIG. 8 is a perspective view of a wire cleaning apparatus 100D according to still another embodiment of the present invention.

Unlike the wire cleaning apparatus 100B illustrated in FIG. 6, the wire cleaning apparatus 100D illustrated in FIG. 8 may further include the heater 150 and the second temperature regulator 152. Except for this, the wire cleaning apparatus 100D illustrated in FIG. 8 is identical to the wire cleaning apparatus 100B illustrated in FIG. 6, and thus a detailed description of the same parts will be omitted. Also, the heater 150 and the second temperature regulator 152 illustrated in FIG. 8 are respectively identical to the heater 150 and the second temperature regulator 152 illustrated in FIG. 7, and thus a description of the same parts will be omitted.

The wire cleaning apparatus 100A; 100B; 100C; 100D illustrated in FIGs. 2 and 5 to 8 may further include a rotation driving unit 160.

The rotation driving unit 160 rotates the tubular member 130A; 130B in a direction designated by the arrow 162, so as to increase a flow speed of the fluid 122 passing through the tubular member 130A; 130B. To this end, the rotation driving unit 160 may include a driving motor (not shown) to rotate the tubular member 130A; 130B. Once the fluid 122 discharged from the first nozzle 120 has been introduced in to the tubular member 130A; 130B, the fluid 122 swirls, for example, in a counterclockwise direction 126 as illustrated in FIG.5 by the spiral guiding portion 136. If the tubular member 130A; 130B is rotated in the same counterclockwise direction 162 as that of the fluid 122 while the swirling fluid 122 passes through the tubular member 130A; 130B, this may allow the fluid 122 to pass through the tubular member 130A; 130B in a further accelerated state. Consequently, removal of the slurry staining the wire 110A may be further facilitated.

In the case of the wire cleaning apparatus 100A; 100B; 100C; 100D according to the above described embodiments, increasing the flow amount and flow speed of the fluid 122 discharged from the first nozzle 120 is helpful to remove the slurry staining the wire 110A. According to the embodiments, instead of increasing the flow amount and flow speed of the fluid 122, by providing the inner surface of the tubular member 130A; 130B with the spiral guiding portion 136, rotating the tubular member 130A; 130B by the rotation driving unit 160, and maintaining an appropriate temperature of the fluid 122 passing through the tubular member 130A; 130B by the first and

second temperature regulators

142 and 152 as described above, it is possible to maximize removal of the slurry staining the wire 110A even with reducing the discharge amount and discharge speed of the fluid 122.

The wire cleaning apparatus 100A; 100B; 100C; 100D illustrated in FIGs. 2 and 5 to 8 may further include a slurry container 170, a filter 172, and a second nozzle 174.

The slurry container 170 accommodates slurry 180 which has been carried by the fluid 122 having been used to clean the wire 110A and dropped from tubular member 130A; 130B through the first opening 133 of the first end 132. The filter 172 filters the slurry 180 accommodated in the slurry container 170, and supplies the filtered slurry into the second nozzle 174. The second nozzle 174 may eject the slurry filtered by the filter 172 to the second movement path of the cleaned wire 110B.

According to the embodiment, the slurry collected in the slurry container 170 after cleaning of the wire 110A stained with the slurry may be filtered and recycled.

For example, the filtered slurry and the cleaned wire 110B may be recycled for sawing of an ingot. Hereinafter, the configuration and operation of a wire sawing apparatus that performs sawing of an ingot using the wire cleaning apparatus 100A; 100B; 100C; 100D of the above described embodiments during a slicing process and a wire sawing method thereof according to an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 9 is a block diagram of a wire sawing apparatus 200 according to an embodiment of the present invention.

Referring to FIG. 9, the wire sawing apparatus 200 includes the above described wire cleaning apparatus 100A; 100B; 100C; 100D illustrated in FIGs. 2 and 5 to 8, at least one ingot holder 210, at least one glass beam member 212, at least one main roller 220, at least one pulley 232, first and

second touch rollers

242 and 244, and first and

second wire bobbins

252 and 254.

The wire cleaning apparatus included in the wire sawing apparatus 200 includes the first nozzle 120, a tubular member 130, a fluid container 140, first and

second temperature regulators

142 and 152, a heater 150, a rotation driving unit 160, a slurry container 170, a filter 172, and second nozzles 174A and 174B.

The tubular member 130 and the second nozzles 174A and 174B illustrated in FIG. 9 respectively correspond to the tubular member 130A; 130B and the second nozzle 174 illustrated in FIGs. 2 and 5 to 8, and thus a detailed description thereof will be omitted. Also, in the wire cleaning apparatus included in the wire sawing apparatus 200 as illustrated in FIG. 9, the same parts as those of FIGs. 2 and 5 to 8 are represented by the same reference numerals, and thus a description thereof will be omitted.

A wire 110C, which is moved at a high speed, serves to saw an ingot 5 by coming into contact with slurry ejected from the second nozzles 174A and 174B. Here, the wire 110C may be a new wire, or may be the recycled wire 110B cleaned within the tubular member 130 as described above.

As described above, the tubular member 130 cleans the wire 110A stained with slurry, thereby generating the recycled wire 110B. The slurry ejected from the second nozzles 174A and 174B, as illustrated in FIG. 9, may be recycled slurry filtered by the filter 172, or may be new slurry differently from the illustration of FIG. 9. For example, new slurry may be SiC powder dissolved in oil.

Accordingly, the wire sawing apparatus 200 of the present embodiment may filter the slurry removed from the wire 110A that is stained with the slurry, thereby reducing ingot sawing costs through recycling when sawing the ingot 5.

To promote an environment in which the ingot 5 is sawed by the wire 110C, the ingot holder 210 serves to hold the ingot 5. The ingot holder 210 may be formed of a metal. During sawing of the ingot 5, there is a risk of the ingot holder 210 being damaged by the wire 110C. To prevent this problem, the glass beam member 212 may be interposed between the ingot holder 210 and the ingot 5. Namely, the glass beam member 212 may be damaged prior to the ingot holder 210 by the wire 110C while the wire 110C saws the ingot 5, which may prevent damage to the ingot holder 210.

The pulley 232 serves to change a movement direction of the

wire

110B, 110C.

The first wire bobbin 252 serves to wind the wire 110B cleaned by the wire cleaning apparatus. In this case, the first touch roller 242 serves to control constant-speed winding of the cleaned wire 110B around the first wire bobbin 252.

When the wire 110A contaminated by the slurry is directly wound around the first wire bobbin 252, the wire sawing apparatus 200 may be contaminated due to scattering of the slurry staining the wire 110A. However, in the wire sawing apparatus 200 according to the embodiment, after the contaminated wire 110A is cleaned using the wire cleaning apparatus 100A; 100B; 100C; 100D, the cleaned wire 110B is wound around the first wire bobbin 252, that may prevent contamination of the wire sawing apparatus 200 by the slurry.

The second wire bobbin 254 serves as a winder of the wire 110C that will be used to saw the ingot 5. The wire wound around the second wire bobbin 254 may be either a new wire as described above or the cleaned wire 110B. Namely, the wire 110B cleaned by the wire cleaning apparatus 100A; 100B; 100C; 100D according to the embodiment may be recycled to saw the ingot 5. The second touch roller 244 serves to control constant-speed unwinding of the wire 110C from the second wire bobbin 254.

If a wafer fabricated by sawing the ingot 5 is a silicon wafer for a solar cell, as illustrated in FIG. 9, the wire 110A; 110B; 110C is moved only in a

single direction

260 or 262. Here, the direction 262 corresponds to the second direction 112 illustrated in FIGs. 2 and 5 to 8. Costs of consuming the wire 110C conventionally required in the wire sawing apparatus for fabrication of a silicon wafer for a solar cell occupy about 40% to 50% of total subsidiary material costs. In consideration of the costs, considerable reduction in subsidiary material costs may be achieved when the wire 110A is cleaned by the wire cleaning apparatus 100A; 100B; 100C; 100D according to the embodiment and the cleaned wire 110B is reused as the wire 110C to saw the ingot 5.

Also, if the wafer fabricated by sawing of the ingot 5 is a semiconductor wafer, the wire 110A; 110B; 110C may be moved in both directions. In this case, the

arrows

260 and 262 illustrated in FIG. 9 may represent both directions, rather than a single direction.

During reciprocation of the wire 110A; 110B; 110C, when the ingot 5 is sawed into wafers using the wire 110A; 110B; 110C which is hardened by slurry staining the wire 110A; 110B; 110C, bowing of the wafer sawed from the ingot 5 may occur. To prevent this problem, a plurality of wire cleaning apparatuses 100A; 100B; 1100C; 100D including the tubular member 130 may be arranged at each position where the reciprocally traveling wire 110A; 110B; 110C is collected.

Hereinafter, a wire sawing method according to the embodiment, which is performed by the wire sawing apparatus 200 illustrated in FIG. 9, will be described with reference to the accompanying drawings.

FIG. 10 is a flowchart explaining a wire sawing method according to an embodiment of the present invention, which is performed by the wire sawing apparatus 200 illustrated in FIG. 9.

Referring to FIGs. 9 and 10, first, new slurry is supplied into the second nozzles 174A and 174B, and subsequently the new slurry is ejected from the second nozzles 174A and 174B to the wire 110C. As the wire 110C stained with the new slurry is moved at a high speed by rotation of the main roller 220, sawing of the ingot 5 is achieved (Operation 310). The wire 110C is contaminated by the slurry during implementation of Operation 310.

After Operation 310, while the wire 110A contaminated by the slurry passes through the tubular member 130 located on the first movement path, the first nozzle 120 discharges the fluid 122 toward the tubular member 130 in the first direction (Operation 320). In this case, the wire 110A is moved in a second direction different from the first direction.

After Operation 320, the wire 110A is cleaned while the fluid 122 discharged into the tubular member 130 passes through the tubular member 130 in the first direction (Operation 330).

After Operation 330, the slurry container 170 accommodates the slurry (or sludge) carried by the fluid 122 that has been used to clean the wire 110A (Operation 340).

After Operation 340, the filter 172 filters the slurry accommodated in the slurry container 170 (Operation 350).

After Operation 350, the second nozzles 174A and 174B eject the slurry, having been filtered by the filter 172, to the second movement path of the cleaned wire (for example, 110C), thereby enabling sawing of the ingot 5 (Operation 360).

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

As described above, a related description has sufficiently been discussed in the above “Best Mode” for implementation of the present invention.

As described above, a wire cleaning apparatus, and a wire sawing apparatus and method using the same according to the embodiments of the present invention may be applied to the field of sawing an ingot for fabrication of a solar cell wafer or a semiconductor wafer.

Claims

A wire cleaning apparatus, comprising:

a first nozzle configured to discharge a fluid in a first direction; and

a tubular member located on a movement path of a wire that is moved in a second direction different from the first direction after contaminated by slurry, the tubular member having an inner surface provided with a spiral guiding portion and serving to clean the wire using the fluid discharged from the first nozzle on the movement path.
The wire cleaning apparatus according to claim 1, wherein the tubular member includes:

a first end having a first opening into which the wire is introduced, the first end providing an exit of the fluid having been used to clean the wire; and

a second end having a second opening into which the fluid discharged from the first nozzle is introduced, the second end providing an exit of the wire having passed through the tubular member.
The wire cleaning apparatus according to claim 2, wherein an outlet of the first nozzle from which the fluid is discharged is located to face the second end.
The wire cleaning apparatus according to claim 2, wherein a diameter of the first opening is different from a diameter of the second opening.
The wire cleaning apparatus according to claim 4, wherein the diameter of the first opening is less than the diameter of the second opening.
The wire cleaning apparatus according to claim 1, wherein the tubular member has a funnel shape.
The wire cleaning apparatus according to claim 2, wherein the tubular member takes the form of a venturi tube having a middle portion, a diameter of which is less than those of the first and second ends.
The wire cleaning apparatus according to claim 7, wherein a distance from the middle portion to the first end is less than a distance from the middle portion to the second end.
The wire cleaning apparatus according to claim 1, wherein the spiral guiding portion includes a spiral groove.
The wire cleaning apparatus according to claim 1, wherein the spiral guiding portion includes a spiral ridge.
The wire cleaning apparatus according to claim 2, wherein pitches of the spiral guiding portion are gradually reduced from the second end to the first end.
The wire cleaning apparatus according to claim 1, further comprising:

a fluid container configured to accommodate the fluid; and

a first temperature regulator configured to regulate a temperature of the fluid supplied from the fluid container and supply the fluid into the first nozzle.
The wire cleaning apparatus according to claim 12, wherein the first temperature regulator regulates the temperature of the fluid within a range of 10℃ to 20℃.
The wire cleaning apparatus according to claim 1, further comprising a heater located around the tubular member to heat the tubular member.
The wire cleaning apparatus according to claim 14, further comprising a second temperature regulator configured to control a temperature of the heater.
The wire cleaning apparatus according to claim 15, wherein the second temperature regulator controls heating of the heater such that the temperature of the fluid is within a range of 10℃ to 20℃.
The wire cleaning apparatus according to claim 1, further comprising a rotation driving unit configured to rotate the tubular member in a direction of accelerating a flow of the fluid passing through the tubular member.
The wire cleaning apparatus according to claim 1, further comprising:

a slurry container in which the slurry carried by the fluid having been used to clean the wire is accommodated;

a filter configured to filter the slurry accommodated in the slurry container; and

a second nozzle configured to eject the filtered slurry to another movement path of the cleaned wire.
A wire sawing apparatus comprising the wire cleaning apparatus according to any one of claims 1 to 18,

wherein the wire sawing apparatus performs sawing of an ingot by the wire contacting the slurry.
The wire sawing apparatus according to claim 19, further comprising:

an ingot holder configured to hold the ingot;

a first wire bobbin, around which a wire cleaned by the wire cleaning apparatus is wound;

a second wire bobbin, around which a wire to be used to saw the ingot is wound;

a first touch roller configured to control constant-speed winding of the cleaned wire around the first wire bobbin; and

a second touch roller configured to control constant-speed unwinding of the wire from the second wire bobbin.
The wire sawing apparatus according to claim 20, wherein the wire wound around the second wire bobbin is the cleaned wire.
The wire sawing apparatus according to claim 19, wherein the wire is moved in a single direction.
The wire sawing apparatus according to claim 19, wherein the wire is moved in both directions.
A wire sawing method, comprising:

sawing an ingot by ejecting slurry to a wire;

discharging a fluid in a first direction; and

cleaning the wire by passing the fluid in the first direction through the interior of a tubular member, wherein the tubular member is located in a movement path of the wire that is moved in a second direction different from the first direction after coming into contact with the slurry, and the tubular member has an inner surface provided with a spiral guiding portion.
The wire sawing method according to claim 24, further comprising:

accommodating the slurry carried by the fluid having been used to clean the wire;

filtering the accommodated slurry; and

ejecting the filtered slurry to another movement path of the cleaned wire to reuse the filtered slurry for sawing of the ingot.