Wire breaking processing method for multi-wire saw

Abstract

This invention discloses a method for handling broken wires in a multi-wire dicing machine, comprising the following steps: S1: Lifting the crystal to separate it from the dicing wire mesh; S2: Reconnecting the broken wire in the dicing wire mesh by driving a wire wheel to pull the dicing wire mesh from the wire feeding side to the wire receiving side, until the welding point of the broken wire misses the projection of the crystal along the direction perpendicular to the dicing wire mesh, and the welding point is close to the wire receiving side; S3: Controlling the crystal to descend, stopping the descent when the dicing wire mesh is pressed into the cutting position on the crystal at a first set height; S4: Observing whether the cutting wire of the dicing wire mesh enters the corresponding cutting kerf on the crystal. This invention's method for handling broken wires in a multi-wire dicing machine reduces damage to the wafer surface, ensures the surface quality of the wafer obtained after dicing, reduces the probability of wafer breakage, and improves the efficiency of handling broken wires.

Description

Technical Field

[0001] This invention relates to the field of cutting machine technology, and in particular to a method for handling wire breakage in a multi-wire cutting machine. Background Technology

[0002] SiC ingots are typically diced into wafers using a multi-wire cutting method. To reduce costs and improve cutting efficiency, the steel wires used in the cutting process are becoming increasingly thinner, and the number of wafers cut is increasing, leading to a higher breakage rate. Once a high-level breakage occurs, re-entering the wafer into the slot is extremely difficult. Current technology typically uses a feeler gauge inserted into the crystal cutting kerf to assist in wafer placement after a high-level breakage. However, as the thickness of single wafers decreases and the number of wafers produced increases, inserting the feeler gauge after a breakage becomes increasingly difficult. Thinner wafers and smaller wafer gaps necessitate the use of even thinner feeler gauges. These thinner gauges are prone to bending, significantly reducing their lifespan. Furthermore, using a bent feeler gauge inserted into the crystal cutting kerf can easily scratch or even break the wafer. This also results in low efficiency, as the wafers become compressed and difficult to separate, further complicating wafer placement. Summary of the Invention

[0003] In view of this, the present invention provides a method for handling broken wires in a multi-wire dicing machine, which reduces damage to the wafer surface, ensures the surface quality of the wafer obtained after dicing, reduces the probability of wafer breakage, and improves the efficiency of handling broken wires.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A method for handling wire breakage in a multi-wire cutting machine includes the following steps:

[0006] S1: Lift the crystal so that it is away from the cutting wire mesh;

[0007] S2: Continuing the broken wire in the cutting wire mesh, drive the wire wheel to pull the cutting wire mesh, so that the cutting wire mesh moves from the wire supply side to the wire take-up side, until the welding point of the broken wire misses the projection of the crystal along the direction perpendicular to the cutting wire mesh, and the welding point is close to the wire take-up side.

[0008] S3: Control the crystal to descend. When the cutting wire mesh is pressed into the cutting position on the crystal at a first set height, the crystal stops descending.

[0009] S4: Observe whether the cutting line of the cutting wire mesh enters the corresponding cutting seam on the crystal. If not, use a toggle tool to move the misaligned cutting line into the corresponding cutting seam on the crystal. If yes, the crystal continues to descend until the cutting wire mesh contacts the cutting position before the wire breaks.

[0010] Optionally, a guide strip is provided near the cutting wire mesh of the crystal, and a plurality of guide slots are provided on the guide strip. The guide slots are connected to the cutting slots one by one. In step S3, when the cutting wire mesh is pressed into the guide slots to a first set height, the crystal stops descending.

[0011] Optionally, the first set height is 1-3mm.

[0012] Optionally, the actuating tool includes a hook and a handle connected together, wherein the end of the hook away from the handle is a pointed end.

[0013] Optionally, the handle integrates a lighting device and a magnifying glass, with the magnifying glass rotatably connected to the handle.

[0014] Optionally, in step S3, the cutting wire mesh is simultaneously routed during the crystal's descent.

[0015] Optionally, in step S3, the crystal descends at a constant speed;

[0016] The uniform descent speed is 100 mm / min.

[0017] Optionally, during the crystal descent, the routing rate of the cutting wire mesh is 0.2% of the routing rate during the cutting process.

[0018] Optionally, in step S4, a line scan camera is used to observe whether the cutting line enters the corresponding cutting seam.

[0019] Optionally, when the crystal is pressed into the cutting wire mesh in step S3, the cutting wire mesh needs to maintain a preset working tension;

[0020] During the wire pulling process in step S4, the cutting wire mesh needs to maintain a preset working tension.

[0021] As can be seen from the above technical solution, the multi-wire cutting machine wire breakage handling method provided by the present invention, when the cutting wire mesh breaks, the crystal leaves the cutting wire mesh, and after the broken wire is reconnected, the crystal descends and presses into the cutting wire mesh. The misaligned cutting wire is moved to the corresponding cutting slit on the crystal by a toggle tool before wafer cutting. This not only improves work efficiency and saves wire breakage handling time, but also avoids damage to the wafer surface when the feeler gauge is used to open the cutting slit compared to the prior art, thus ensuring the surface quality of the wafer obtained after cutting and reducing the probability of wafer breakage. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A schematic diagram of a crystal with a guide strip connected to it disposed on a cutting wire mesh, according to an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of a crystal connected to a guide strip at one angle, provided in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of a crystal connected with a guide strip from another angle, provided in an embodiment of the present invention.

[0026] Figure 4 This is a schematic diagram of a portion of a cutting seam on a crystal provided in an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of a crystal after it has been pressed into a diced wire mesh, as provided in an embodiment of the present invention.

[0028] Figure 6 This is a schematic diagram of the structure provided in an embodiment of the present invention, showing how misaligned cutting lines of a cutting wire mesh are moved to the corresponding cutting seam on a crystal.

[0029] Figure 7 This is a schematic diagram of the structure of a toggle tool provided in an embodiment of the present invention;

[0030] Figure 8 This is a schematic diagram of the structure of a toggle tool provided in another embodiment of the present invention;

[0031] Figure 9 This is a schematic diagram of the structure of the magnifying glass on the toggle tool provided in the third embodiment of the present invention after it has been retracted;

[0032] Figure 10 for Figure 9 A schematic diagram of the structure of the magnifying glass on the toggle tool provided in the embodiment.

[0033] The meanings of the labels in the figures are as follows:

[0034] 1. Resin holder,

[0035] 2. Crystals

[0036] 201. Cutting seam

[0037] 3. Guide strip,

[0038] 301. Guide joint,

[0039] 4. Cutting wire mesh,

[0040] 5. Use the tool to turn it.

[0041] 501. Hook; 502. Handle; 503. Lighting device; 504. Magnifying glass. Detailed Implementation

[0042] This invention discloses a method for handling broken wires in a multi-wire dicing machine, which reduces damage to the wafer surface, ensures the surface quality of the wafer obtained after dicing, reduces the probability of wafer breakage, and improves the efficiency of handling broken wires.

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Please see Figures 1 to 10 This invention provides a method for handling broken wires in a multi-wire dicing machine, comprising the following steps: S1: Lifting the crystal 2 to move it away from the dicing wire mesh 4, facilitating the reconnection of broken wires in the dicing wire mesh 4. S2: Reconnecting the broken wires in the dicing wire mesh 4 by driving the wire wheel to pull the dicing wire mesh 4 from the wire supply side to the wire take-up side, until the welding point of the broken wire misses the projection of the crystal 2 along the direction perpendicular to the dicing wire mesh 4, and the welding point is close to the wire take-up side, thereby avoiding wear of the welding point on the cut wafer. S3: Controlling the crystal 2 to descend, stopping the descent when the dicing wire mesh 4 is pressed into the cutting position on the crystal 2 at a first set height H. S4: Observing whether the cutting wire of the dicing wire mesh 4 enters the corresponding cutting slit 201 on the crystal 2. If not, using a toggle tool 5 to move the misaligned cutting wire into the corresponding cutting slit 201 on the crystal 2. If yes, the crystal 2 continues to descend until the dicing wire mesh 4 contacts the cutting position before the wire breakage, and then wafer cutting continues.

[0045] The dicing wire mesh 4 is used to cut the crystal 2 into multiple wafers. The dicing wire mesh 4 is a mesh composed of multiple steel wires arranged in a grid. The dicing wires are steel wires. The crystal 2 is connected to the lifting device via a resin support 1. The lifting device is a commonly used device in the prior art and will not be described in detail here. The crystal 2 is connected to the resin support 1.

[0046] The multi-wire cutting machine wire breakage handling method of the present invention, when the cutting wire mesh 4 breaks, the crystal 2 leaves the cutting wire mesh 4. After the broken wire is reconnected, the crystal 2 descends and presses into the cutting wire mesh 4. The misaligned cutting wire is moved to the corresponding cutting slit 201 on the crystal 2 by the tossing tool 5 before wafer cutting. This not only improves work efficiency and saves wire breakage handling time, but also avoids damage to the wafer surface when the feeler gauge is used to open the cutting slit 201 to insert the wire, compared with the prior art of using a feeler gauge to open the cutting slit 201, thus ensuring the surface quality of the wafer obtained after cutting and reducing the probability of wafer breakage.

[0047] To facilitate observation of cutting lines that have not yet entered the cutting slit 201, and to facilitate the movement of cutting lines into the cutting slit 201, a guide strip 3 is provided on the crystal 2 near the cutting wire mesh 4. Multiple guide slots 301 are provided on the guide strip 3, and each guide slot 301 corresponds to and is connected to the cutting slit 201. In step S3, when the cutting wire mesh 4 is pressed into the guide slot 301 to a first predetermined height H, the crystal 2 stops descending. Specifically, before cutting, the entire guide strip 3 is adhered to the crystal 2 near the cutting wire mesh 4. When the cutting wire mesh 4 is cut, guide slots 301 are cut on the guide strip 3, and then cutting slits 201 are cut on the crystal 2. This method ensures the reliable positional correspondence between the guide slots 301 and the cutting slits 201. The first predetermined height H is the height difference between the bottom surface of the guide strip 3 furthest from the crystal 2 and the cutting wire mesh 4.

[0048] Furthermore, the first set height H is 1-3mm. Setting the first set height H within the above range ensures both the limiting of the cutting line entering the cutting slit 201 and avoids excessive tension on the cutting line not entering the cutting slit 201, which could affect the service life of the cutting line. Preferably, the first set height H is 2mm.

[0049] In one specific embodiment, the actuating tool 5 includes a hook 501 and a handle 502 connected together. The end of the hook 501 away from the handle 502 is a pointed end, which facilitates the insertion of the hook 501 between the wire meshes. To facilitate hooking misaligned cutting lines into the corresponding cutting seams 201, the pointed end of the hook 501 is a V-shaped end or a U-shaped end, such as... Figure 7 As shown, the pointed end of the eagle beak hook 501 is U-shaped, as... Figure 8 As shown, the pointed end of the hook 501 is V-shaped. In one embodiment, the actuating tool 5 may consist only of the hook 501 and the handle 502, see reference. Figure 7 and Figure 8 As shown. In another embodiment, other functional components may also be included, such as Figure 9 and Figure 10As shown, the handle 502 integrates an illumination device 503 and a magnifying glass 504. The illumination device 503 is fixedly connected to the handle 502, and the magnifying glass 504 is rotatably connected to the handle 502. Furthermore, the illumination end of the illumination device 503 is positioned near the beak hook 501, facilitating illumination when moving the cutting line and aiding in observation of the cutting line. The illumination device 503 can be cylindrical, and the magnifying glass 504 is rotatably connected to it. When observation of the cutting line is needed, the magnifying glass 504 is opened for easy observation; when observation is not needed, the magnifying glass 504 is retracted. In this embodiment, the moving tool 5 integrates the beak hook 501, the illumination device 503, and the magnifying glass 504, allowing the operator to perform precise operations under optimal visibility. Throughout the wire-moving process, the main roller system of the multi-wire cutting machine must maintain a preset working tension. The illumination device 503 and the magnifying glass 504 are existing technologies and will not be described in detail here.

[0050] In step S3, as the crystal 2 descends, the cutting wire mesh 4 simultaneously moves along the wire, maintaining a constant tension on the cutting wire mesh 4 during this period. Simultaneously, in step S3, the crystal 2 descends at a uniform speed, facilitating the entry of the cutting wire into the corresponding cutting slit 201. Specifically, the uniform descent speed can be 100 mm / min. A descent speed that is too fast is not conducive to the crystal 2 aligning and pressing into the cutting wire mesh 4, while a descent speed that is too slow affects work efficiency.

[0051] During the descent of crystal 2, the wire routing speed of the cutting wire mesh 4 is 0.2% of the wire routing speed during the cutting process, so as to facilitate the crystal 2 being pressed into the cutting wire mesh 4. During the descent of crystal 2, the cutting wire mesh 4 is routed to facilitate its entry into the cutting slit 201.

[0052] To facilitate online assessment of the cutting quality of the cutting wire in the cutting mesh 4, in step S4, a line scan camera is used to observe whether the cutting wire enters the corresponding cutting seam 201. The line scan camera mounted on the machine is used to scan the moved cutting wire, and an image processing algorithm is used to analyze the position of the cutting wire in the cutting seam, achieving automatic assessment.

[0053] To facilitate the entry of the cutting wires into the cutting slit 201, when the crystal 2 descends and presses onto the cutting wire mesh 4 in step S3, the cutting wire mesh 4 must maintain a preset working tension; similarly, during the wire-pulling process in step S4, the cutting wire mesh 4 must maintain a preset working tension. When observing and pulling the cutting wire mesh 4, start from the non-broken area side of the cutting wire mesh 4 and proceed sequentially towards the broken area, checking each cutting wire one by one to avoid omissions. In step S4, when the crystal 2 descends to the cutting position of the cutting wire mesh 4 before the breakage, recheck whether each cutting wire of the cutting wire mesh 4 is within the corresponding cutting slit 201 to avoid cutting errors.

[0054] The multi-wire cutting machine wire breakage handling method of the present invention, after the broken wire of the cutting wire mesh 4 is reconnected, when it is pressed into the cutting gap, does not rely on a feeler gauge, but combines precise control of guide pressing with moving wire operation, and is supplemented by a special moving tool 5 and online judgment of the groove quality, so as to achieve safe, efficient and reliable resetting of the cutting wire.

[0055] The multi-wire cutting machine wire breakage handling method of the present invention transforms wire breakage handling from an operation that relies on personal skills into a standardized, monitorable, highly efficient, and stable process with an extremely low breakage rate, significantly improving production efficiency, ensuring product quality, and resulting in better consistency in the quality of the cut wafers.

[0056] In the description of this solution, it should be understood that the terms "upper", "lower", "vertical", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this solution.

[0057] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this solution, "multiple" means two or more, unless otherwise explicitly specified.

[0058] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0059] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for handling wire breakage in a multi-wire cutting machine, characterized in that, Includes the following steps: S1: Lift the crystal so that it is away from the cutting wire mesh; S2: Continuing the broken wire in the cutting wire mesh, drive the wire wheel to pull the cutting wire mesh, so that the cutting wire mesh moves from the wire supply side to the wire take-up side, until the welding point of the broken wire misses the projection of the crystal along the direction perpendicular to the cutting wire mesh, and the welding point is close to the wire take-up side. S3: Control the crystal to descend. When the cutting wire mesh is pressed into the cutting position on the crystal at a first set height, the crystal stops descending. S4: Observe whether the cutting line of the cutting wire mesh enters the corresponding cutting seam on the crystal. If not, use a toggle tool to move the misaligned cutting line into the corresponding cutting seam on the crystal. If yes, the crystal continues to descend until the cutting wire mesh contacts the cutting position before the wire breaks.

2. The method for handling wire breakage in a multi-wire cutting machine according to claim 1, characterized in that, A guide strip is provided on the crystal near the cutting wire mesh, and multiple guide slots are provided on the guide strip. The guide slots are connected to the cutting slots one by one. In step S3, when the cutting wire mesh is pressed into the guide slots to a first set height, the crystal stops descending.

3. The method for handling wire breakage in a multi-wire cutting machine according to claim 2, characterized in that, The first set height is 1-3mm.

4. The method for handling wire breakage in a multi-wire cutting machine according to claim 1, characterized in that, The actuating tool includes a hook and a handle connected together, with the end of the hook away from the handle being a pointed end.

5. The method for handling wire breakage in a multi-wire cutting machine according to claim 4, characterized in that, The handle integrates a lighting device and a magnifying glass, with the magnifying glass rotatably connected to the handle.

6. The method for handling wire breakage in a multi-wire cutting machine according to claim 5, characterized in that, In step S3, as the crystal descends, the cutting wire mesh is simultaneously routed.

7. The method for handling wire breakage in a multi-wire cutting machine according to claim 6, characterized in that, In step S3, the crystal descends at a constant speed; The uniform descent speed is 100 mm / min.

8. The method for handling wire breakage in a multi-wire cutting machine according to claim 6, characterized in that, During the crystal descent, the wire rate of the cutting mesh is 0.2% of the wire rate during the cutting process.

9. The method for handling wire breakage in a multi-wire cutting machine according to claim 1, characterized in that, In step S4, a line scan camera is used to observe whether the cutting line enters the corresponding cutting seam.

10. The method for handling wire breakage in a multi-wire cutting machine according to claim 1, characterized in that, When the crystal is pressed into the cutting wire mesh in step S3, the cutting wire mesh needs to maintain a preset working tension; During the wire pulling process in step S4, the cutting wire mesh needs to maintain a preset working tension.

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