Method for laying cutting wire net for half spliced silicon rods

Abstract

The invention provides a half-piece spliced silicon rod cutting wire net laying method. According to the method, the anti-oblique line net is arranged at the head of the main shaft, and the line net gap is formed by pasting the adhesive tape, so that the stress of the line net in the cutting process is uniform and stable, the defects of TTV, steps and the like of cut silicon wafers are reduced, and the line breaking and clamping risks are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic silicon rod cutting, and in particular to a method for laying a wire mesh for cutting half-piece spliced ​​silicon rods. Background Art

[0002] The traditional wire mesh laying method for cutting half-piece spliced ​​silicon rods is that the wire mesh flat groove is perpendicular to the main axis, that is, the single wire is perpendicular to the main axis, and the wires used for cutting the wire mesh are parallel to each other. When dividing the wire mesh gap, the wire mesh gap is manually pulled out on the main axes on both sides, or the wire mesh is reversed by high-speed reversal of the main axis to divide the gap. There are many problems with this type of wire mesh laying method: 1. The wire mesh is a flat groove perpendicular to the spindle, or the cutting wire gradually becomes inclined toward the forward direction of the wire mesh during the running of the cutting wire. These two situations are more likely to cause uneven thickness of the cut silicon wafers, resulting in more TTV and step anomalies; 2. The method of manually pulling out the wire mesh gaps on both sides is difficult to ensure that the wire mesh gaps on both sides are of equal width, and it is difficult to ensure that all wire meshes are parallel to each other, which can easily lead to uneven force during the cutting process and increase the risk of wire breakage and wire jamming; 3. Although the gaps on both sides of the wire mesh separated by the high-speed reversal spindle are of equal width, empty grooves and overlapping wires are easily generated during the high-speed forward or backward movement of the wire mesh, which in turn leads to wire winding, increasing the loss and time cost of laying the wire mesh; 4. The single cutting wire at the edge of the flat groove or inclined wire mesh is more compressed by the thick silicon block on its side, and is more likely to deviate from its original position during the cutting process, causing wire jumps and wire breaks, and more likely to cause wire jams during the retraction process. Summary of the invention

[0003] The object of the present invention is to provide a method for laying a wire mesh for cutting half-piece spliced ​​silicon rods to solve the above-mentioned problems existing in the prior art.

[0004] To achieve the above object, the present invention provides the following technical solutions: A method for laying a wire net for cutting a half-piece spliced ​​silicon rod, wherein a cutting machine for cutting a half-piece spliced ​​silicon rod comprises two parallel main shafts, each main shaft is provided with a wire groove, and a cutting wire is laid on the main shaft through the wire groove to form a wire net. According to the direction of the machine, facing the machine, the left side is the left main shaft, and the right side is the right main shaft. The wire net between the two main shafts forms a cutting surface. With the cutting surface as a reference, the cutting wire runs from the right main shaft to the left main shaft and then goes back to the right main shaft from under the left main shaft, and is laid cyclically to form a wire net. The method comprises the following steps: S1: Adjust and lay out a reverse slash net on the spindle head that is tilted toward the right spindle head; S2: Set a wire mesh gap required for the silicon rod joint at the left main axis; S3: Use two pieces of tape to stick the upper and lower surfaces of the wire mesh on both sides of the gap respectively; S4: operate the main shaft to rotate so that the gap extends to between the two main shafts and ensure that the wire mesh gap between the two main shafts is of equal width, maintain the reverse tilt and tear off the tape; S5: Continue running the line and laying an appropriate wire network; S6: Repeat steps S2-S5 to sequentially lay out the number of equal-width wire mesh gaps required for cutting and splicing silicon rods in the length direction of the main axis.

[0005] Preferably, in step S1, the degree of inclination of the spindle head wire mesh is controlled by the number of empty slots in the spindle head, wherein the number of empty slots in the left spindle head is 3-5 more than that in the right spindle head.

[0006] Preferably, in step S2, a wire mesh gap required at the silicon rod joint is set at the left main axis by pulling, wherein the wire mesh gap width is 2.0 mm-3.5 mm.

[0007] Preferably, in step S3, the adhesive surfaces of the two tapes are pasted relative to each other at the same position of the wire mesh on both sides of the gap so that the two tapes are bonded to each other to fix the width of the wire mesh gap between the tapes.

[0008] Further, one of the adhesive tapes is a transparent hard adhesive tape, and the adhesive surface of the transparent hard adhesive tape is adhered to the upper layer of the wire mesh downward. More preferably, the length of the two adhesive tapes is 1 cm-2.5 cm.

[0009] Preferably, in step S4, manipulating the main shaft to rotate includes first rotating the main shaft in the forward direction, allowing the tape to run one circle between the main shafts so that the set wire mesh gap extends to between the two main shafts, and then tearing off the tape and spraying the adhesive remover.

[0010] Preferably, in step S5, the width of a single wire mesh laid in the running line is 29 mm-34 mm.

[0011] Preferably, in step S6, the number of wire meshes laid in the running line is 22-28.

[0012] Furthermore, the method further comprises step S7: adjusting the wire mesh gap to align with the joint seams between the silicon blocks of the spliced ​​silicon rods and then slicing the silicon blocks according to the cutting process.

[0013] Specifically, in step S7, the steps of adjusting the wire mesh gap to align with the splicing seam between the silicon blocks in the spliced ​​silicon rods and then adapting the cutting process for slicing include: sticking tape on the left or right side of a single wire seam, and rotating forward or reversely along the laying direction of the wire mesh, controlling the wire mesh gap to align with the gap between the silicon blocks in the spliced ​​silicon rods, and adapting the cutting process for slicing.

[0014] Preferably, the parameters of the cutting process are: main roller wheelbase is 315mm-435mm, single wire mesh width is 29mm-34mm, starting cutting position is -1mm, cutting depth is 187mm-215mm, table speed is 1200μm→3200μm→70μm / min, line speed is 800m→2300m→2100m / min, supply and return line volume is 570m-1700m, and cutting time is 60min-140min.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The laid wire mesh is tilted in the opposite direction of the wire mesh's forward movement on the main axis. The wire mesh is subjected to more uniform and stable force during the cutting process, which is beneficial to reducing defects such as TTV and steps in the cutting of silicon wafers; 2. By using adhesive tape to divide the wire mesh gaps, it can effectively ensure that all wire meshes are parallel and the gaps on both sides of the wire mesh are of equal width, so that the wire mesh is more evenly stressed during the cutting process, reducing the risk of wire breakage and jamming; 3. By using adhesive tape to divide the gaps in the wire mesh, it can effectively ensure that the gaps on both sides of the wire mesh are of equal width and there are no empty slots or overlapping wires, which greatly improves the efficiency of laying the wire mesh and reduces the loss and risk of winding the wire mesh; 4. The cutting wire at the edge of the reverse oblique mesh gap is less compressed by the thick silicon block on its side, making it more stable during the cutting process, reducing the risk of wire breakage and wire jamming during tool withdrawal. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram showing the reverse or forward oblique distribution of the wire mesh on the main axis of the slicer from a top-down perspective; Figure 2 A schematic diagram showing the difference between the anti-slant and positive-slant distribution of the wire mesh on the main axis of the slicer from a normal perspective; Figure 3 1 is a schematic top view of the inclined groove for laying the head wire mesh in step S1 of the method of the present invention; Figure 4 is a top view schematic diagram of manually pulling out the gaps in the wire mesh in step S2 of the method of the present invention; Figure 5 is a schematic top view of the adhesive tape below the wire mesh in step S3 of the method of the present invention; Figure 6 is a schematic top view of the adhesive tape above the wire mesh in step S3 of the method of the present invention; Figure 7 is a side view schematic diagram of the rotating spindle in step S4 of the method of the present invention; Figure 8 is a top view schematic diagram of a partial reverse slash net effect achieved in steps S5 and S6 of the method of the present invention; Fig. 9This is a schematic diagram of the prior art method of comparative example 1, in which the gaps are first pulled out on the main shafts on both sides in steps 2 and 3, wherein during the operation, no tape is pasted on the upper and lower sides of the wire mesh where the gap is located; Fig.10 This is a schematic diagram of further pulling out a gap on the third axis in step 4 of the prior art method of comparative example 1; Fig.11 It is a schematic diagram of the wire mesh gap obtained by using the prior art method of comparative example 1. DETAILED DESCRIPTION

[0017] The cutting of half-piece spliced ​​silicon rods needs to take into account the splicing between the silicon rods, and the wire mesh should be properly adjusted to make wire mesh gaps for the splicing seams, otherwise it will cause various problems such as TTV and step abnormalities. The traditional conventional wire mesh laying method is that the main operator directly pulls out the wire mesh gaps on the main shafts on both sides, but this method brings a higher wire jam rate. The present invention develops a new cutting wire mesh laying method, which effectively solves the above problems.

[0018] In an exemplary embodiment, the method of the present invention is as follows: S1: The spindle head is adjusted by the groove to lay the reverse oblique wire mesh in the opposite direction of the overall forward direction of the cutting wire; S2: Manually pull out the wire mesh gap required for the silicon rod joint on the left spindle; S3: Use ordinary tape and transparent hard tape strips to stick the upper and lower surfaces of the wire mesh on both sides of the gap respectively; S4: Operate the main shaft to rotate to ensure that the left and right sides of the wire mesh gap are of equal width and maintain the reverse slope and tear off the tape; S5: Continue running the line and laying an appropriate wire network; S6: repeating steps S2-S5 to sequentially lay the number of equal-width seams required for cutting and splicing silicon rods; S7: Adjust the wire mesh gap to align with the joint seams between the silicon blocks of the spliced ​​silicon rods and then adapt the cutting process to perform slicing.

[0019] Preferably, the wire mesh is not completely perpendicular to the main axis, and a single wire is inclined to a certain extent with respect to the main axis, and the inclination direction is opposite to the forward direction of the main axis during the laying of the wire mesh, and each wire on the entire wire mesh is parallel to each other.

[0020] Preferably, in step S1, the degree of inclination of the wire mesh of the spindle head is controlled by the number of empty slots of the spindle head, and the number of empty slots of the left spindle head needs to be 3-5 greater than the number of empty slots of the right spindle head.

[0021] Preferably, in step S2, the wire mesh gap width is 2.0 mm-3.5 mm.

[0022] Preferably, in step S3, the common tape is attached to the wire mesh with the lower adhesive surface facing upward, and the transparent hard tape is attached to the wire mesh with the upper adhesive surface facing downward, and the two tapes are bonded to each other to fix the wire mesh gaps between the tapes.

[0023] Preferably, the ordinary tape and the transparent hard tape are cut into 1cm-2.5cm, and the cutting wire covering both sides of the single wire mesh gap is 3mm-10mm.

[0024] Preferably, in step S4, the main shaft is operated to rotate one circle in the positive direction along the laying direction of the wire mesh, and then the tape is torn off and the adhesive remover is sprayed.

[0025] Preferably, in step S5, the width of a single wire mesh is 29 mm to 34 mm.

[0026] Preferably, in step S6, the number of wire meshes laid out during the running and laying process is the same as the number of silicon blocks for splicing silicon rods, 22-28.

[0027] Preferably, in step S7, tape is applied to the left or right side of a single wire seam, and the wire mesh is rotated forward or reversely along the laying direction to control the wire mesh gap to align with the gap between silicon blocks in the spliced ​​silicon rods, and the slicing is performed according to the cutting process. Preferably, the cutting process parameters are: main roller wheelbase is 315mm-435mm, single wire mesh width is 29mm-35mm, starting cutting position is -1mm, cutting depth is 187mm-215mm; table speed is 1200μm→3200μm→70μm / min, line speed is 800m→2300m→2100m / min, supply and return line volume is 570m-1700m, and cutting time is 60min-140min.

[0028] The defects of the conventional method are: 1. Failure to measure the head bevel causes the entire main axis network to be not reversely inclined, but flat or positively inclined, and experience has shown that the line jam rate of flat or positively inclined is higher than that of reversely inclined; 2. Without double-layer tape, the left and right main axes are judged by the manual feel of the main operator to pull out the wire mesh gap, and it is impossible to ensure that the wire mesh gap widths of the main axes on both sides are equal, and there will be wire mesh gap size heads, that is, the wire mesh gaps between the two main axes are not equal in width, which will cause the inclination degrees of each small wire mesh gap of the entire wire mesh group to be different, which is easy to cause TTVB and steps to increase; and if the first step of measuring the head bevel is performed without using the double-layer tape method, the reverse inclination of the entire wire mesh group cannot be guaranteed, which will also cause the wire mesh to become flat or positively inclined as it is laid later, thereby causing the line jam rate to increase. Compared with the conventional wire mesh laying method, the method of the present invention adopts the wire mesh dividing method of taping, and determines the reverse inclination degree of the wire mesh by measuring the head bevel, and then ensures that the width of the main axis seams on both sides is equal by taping, thereby reducing the line jam rate.

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Example 1

[0032] The method for laying a wire mesh by splicing half-chip silicon rods disclosed in this embodiment comprises the following steps: Step 1: If Figure 3 As shown, the spindle head is adjusted by shifting the slots to lay a reverse oblique wire mesh opposite to the overall forward direction of the cutting wire, and the number of empty slots on the left spindle head is 3-5 greater than that on the right spindle head.

[0033] Step 2: If Figure 4 As shown, manually pull out a wire mesh gap required for the silicon rod splicing seam next to the left main axis mesh, and the wire mesh gap width is 2.0mm-3.5mm; Step 3: If Figure 5 , Figure 6 As shown, use 1cm-2.5cm ordinary tape and transparent hard tape strips to stick to the upper and lower surfaces of the wire mesh on both sides of the gap respectively; Among them, the ordinary tape is attached to the wire mesh with the lower adhesive surface facing upwards, and the transparent hard tape is attached to the wire mesh with the upper adhesive surface facing downwards. The two tapes are bonded to each other to fix the wire mesh gap between the tapes, and at the same time cover the cutting wire 3mm-10mm on both sides of the single wire mesh gap; Step 4: If Figure 7 As shown, the main shaft is operated to rotate one circle in the positive direction along the laying direction of the wire mesh to ensure that the left and right sides of the wire mesh gap are of equal width and maintain the reverse slope, tear off the pasted tape and spray the adhesive remover; Step 5: Continue laying out a wire mesh with a width of 29mm-34mm; Step 6: If Figure 8 As shown, repeat steps 2 to 5 to sequentially lay 22-28 equal-width seams required for cutting and splicing silicon rods; Step 7: Adjust the wire mesh gap to align with the joint seams between the silicon blocks of the spliced ​​silicon rods and then adapt the cutting process for slicing; Among them, the cutting process parameters are: main roller wheelbase is 315mm-435mm, single wire mesh width is 29mm-35mm, starting cutting position is -1mm, cutting depth is 187mm-215mm; table speed is 1200μm→3200μm→70μm / min, line speed is 800m→2300m→2100m / min, supply and return line volume is 570m-1700m, and cutting time is 60min-140min.

[0034] 5960 examples of the above embodiment are selected, and the slice abnormality rate and silicon wafer yield are as follows: The slicing wire breakage rate is 6.74%, the wire withdrawal breakage rate is 9.97%, the TTVB category accounts for 0.31%, the TTVC category accounts for 0.12%, the step category accounts for 0.48%, the thin slice B accounts for 0.13%, and the comprehensive A-level rate is 95.05%.

[0035] Comparative Example 1 The conventional wire mesh laying method disclosed in this embodiment comprises the following steps: Step 1: Lay the first wire mesh group directly on the spindle head. The conventional wire mesh laying method does not require measuring and setting the head bevel.

[0036] Among them, since the head bevel groove is not measured and set, it is impossible to ensure that the head wire mesh is reversely inclined.

[0037] Step 2: Manually pull out a mesh gap required for the silicon rod joint next to the main axis mesh on the left side. The mesh gap width is 2.0mm-3.5mm; Step 3: Manually pull out a wire mesh gap required for the silicon rod splicing seam next to the main axis mesh on the right side. The wire mesh gap width is 2.0mm-3.5mm.

[0038] Among them, since the gaps on both sides of the wire mesh are manually pulled, it is impossible to ensure that the gaps on both sides of the wire mesh are of equal width. Fig. 9 As shown; Step 4: Use the same method to manually pull out a wire mesh gap required for the silicon rod joint on the third axis below. The wire mesh gap width is 2.0mm-3.5mm; operate the main axis to rotate one circle in the positive direction of laying the wire mesh, tear off the pasted tape and spray the glue remover. The process is as follows: Fig.10 As shown; Step 5: Continue laying out a wire mesh with a width of 29mm-34mm; Step 6: Repeat the above steps 2 to 5 to sequentially lay 22-28 equal-width seams required for cutting and splicing silicon rods; Among them, because the double-layer tape was not pasted, the gaps in the overall wire mesh were uneven and of different sizes, and the entire wire mesh group could not be kept parallel. Fig.11 shown.

[0039] Step 7: Adjust the wire mesh gap to align with the joint seams between the silicon blocks of the spliced ​​silicon rods and then adapt the cutting process for slicing; Among them, the cutting process parameters are: main roller wheelbase is 315mm-435mm, single wire mesh width is 29mm-35mm, starting cutting position is -1mm, cutting depth is 187mm-215mm; table speed is 1200μm→3200μm→70μm / min, line speed is 800m→2300m→2100m / min, supply and return line volume is 570m-1700m, and cutting time is 60min-140min.

[0040] 715 slices were sliced ​​using the traditional wire mesh method. The abnormality rate of slices and the yield rate of silicon wafers are as follows: The slicing breakage rate is 25.45%, the withdrawing breakage rate is 53.29%, the TTVB category accounts for 1.52%, the TTVC category accounts for 0.18%, the steps account for 0.84%, the thin slices account for 1.28%, and the comprehensive A-level rate is 94.01%.

[0041] It can be seen from the above-mentioned Example 1 and Comparative Example 1 that by fixing the wire mesh by means of adhesive tape and tilting the wire mesh in the direction opposite to the traveling direction of the wire mesh, the TTV is significantly reduced, the steps are significantly reduced, the flakes are significantly reduced, and the cutting yield is significantly improved, which is beneficial to improving the subsequent component yield; Tilt the wire mesh in the opposite direction of its laying direction, so that the wire mesh is subjected to more uniform and stable force during cutting. The cutting wire at the edge of the wire mesh gap is less pressed by the thick silicon block on its side, and the wire breakage rate and wire withdrawal breakage rate are significantly reduced. By using tape to divide the wire mesh gaps, it can be effectively ensured that all wire meshes are parallel and the gaps on both sides of the wire mesh are of equal width. The TTV rate, step rate and thin film rate are significantly reduced, and the yield is significantly improved.

[0042] The matters not described in detail in the present invention are all known technologies to those skilled in the art.

[0043] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified and replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for laying a wire net for cutting a half-piece spliced ​​silicon rod, wherein a cutting machine for cutting a half-piece spliced ​​silicon rod comprises two parallel main shafts, each main shaft is provided with a wire groove, and the cutting wire is laid on the main shaft through the wire groove to form a wire net. According to the direction of the machine, facing the machine, the left side is the left main shaft, and the right side is the right main shaft. The wire net between the two main shafts forms a cutting surface. With the cutting surface as a reference, the cutting wire runs from the right main shaft to the left main shaft and then goes back to the right main shaft from under the left main shaft, and is laid into a wire net in a cycle, characterized in that: The method comprises the following steps: S1: Adjust and lay out a reverse slash net tilted toward the right spindle head on the right spindle head; S2: Set a wire mesh gap required for the silicon rod joint at the left main axis; S3: Use two pieces of tape to stick the upper and lower surfaces of the wire mesh on both sides of the gap respectively; S4: operate the main shaft to rotate so that the gap extends to between the two main shafts and ensure that the wire mesh gap between the two main shafts is of equal width, maintain the reverse tilt and tear off the tape; S5: Continue running the line and laying an appropriate wire network; S6: Repeat steps S2-S5 to sequentially lay out the number of equal-width wire mesh gaps required for cutting and splicing silicon rods in the length direction of the main axis.

2. The method according to claim 1, characterized in that In step S1, the degree of inclination of the spindle head wire mesh is controlled by the number of empty slots in the spindle head, wherein the number of empty slots in the left spindle head is 3-5 more than that in the right spindle head.

3. The method according to claim 1, characterized in that In step S2, a wire mesh gap required at the silicon rod joint is set at the left main axis by pulling, wherein the wire mesh gap width is 2.0 mm-3.5 mm.

4. The method according to claim 1, characterized in that In step S3, the adhesive surfaces of the two tapes are pasted relative to each other at the same position of the wire mesh on both sides of the gap so that the two tapes are bonded to each other to fix the width of the wire mesh gap between the tapes.

5. The method according to claim 4, characterized in that One of the adhesive tapes used is a transparent hard adhesive tape, and the adhesive surface of the transparent hard adhesive tape is adhered to the upper layer of the wire mesh downward.

6. The method according to claim 5, characterized in that The length of the two tapes is 1cm-2.5cm.

7. The method according to claim 1, characterized in that In step S4, manipulating the spindles to rotate includes first rotating the spindles in the forward direction, allowing the tape to run one circle between the spindles so that the set wire mesh gap extends to between the two spindles, and then tearing off the tape and spraying the adhesive remover.

8. The method according to claim 1, characterized in that In step S5, the width of a single wire mesh laid by the running wire is 29 mm-34 mm.

9. The method according to claim 1, characterized in that In step S6, the number of wire meshes laid in the running line is 22-28.

10. The method according to claim 1, characterized in that The step S7 is also included: adjusting the wire mesh gap to align with the joint seams between the silicon blocks of the spliced ​​silicon rods and then adapting the cutting process to perform slicing.

11. The method according to claim 10, characterized in that In step S7, the steps of adjusting the wire mesh gap to align with the splicing seam between the silicon blocks in the spliced ​​silicon rods and then adapting the cutting process for slicing include: sticking tape on the left or right side of a single wire seam, and rotating forward or reversely along the laying direction of the wire mesh, controlling the wire mesh gap to align with the gap between the silicon blocks in the spliced ​​silicon rods, and adapting the cutting process for slicing.

12. The method according to claim 11, characterized in that The parameters of the cutting process are: main roller wheelbase is 315mm-435mm, single wire mesh width is 29mm-34mm, starting cutting position is -1mm, cutting depth is 187mm-215mm, table speed is 1200μm→3200μm→70μm / min, line speed is 800m→2300m→2100m / min, supply and return line volume is 570m-1700m, and cutting time is 60min-140min.

13. The method according to claim 1, characterized in that A third axis is included below the two main axes, and the cutting wire is wound around the two main axes and the third axis to form a wire net.

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