A slot wheel and a thread cutting machine provided with the slot wheel

Abstract

The utility model provides a kind of grooved wheel and the thread cutting machine with the grooved wheel, including grooved wheel main body, the wiring slot is arranged in the axial direction on the grooved wheel, the grooved wheel includes first end and second end, the groove spacing of adjacent wiring slot of the first end is greater than the groove spacing of adjacent wiring slot of the second end.The utility model has the beneficial effect that effectively solve the technical problem that wear is caused due to diamond wire in the cutting process, effective wire diameter is difficult to keep constant, affect the uniformity of silicon wafer thickness, cause raw material waste, reduce the difference of silicon wafer thickness, improve the uniformity of silicon wafer thickness, improve the quality of silicon wafer, increase the cutting piece number, reduce the waste of raw material, prevent the abnormality of jumper.

Description

Technical Field

[0001] This utility model belongs to the field of silicon rod processing technology, and in particular relates to a grooved wheel and a wire cutting machine equipped with the grooved wheel. Background Technology

[0002] In silicon ingot processing, a wire cutter uses grooved rollers to drive diamond wires, cutting the silicon ingot into silicon wafers. In existing technology, the groove spacing on the grooved rollers is uniform. In the forward slicing process, the thickness of the silicon wafers cut from the head to the tail of the silicon ingot increases linearly. In the reverse slicing process, the wafer thickness increases linearly from the tail to the head of the silicon ingot.

[0003] The thickness of the silicon wafers cut from the head to the tail of the silicon rod decreases linearly. Figure 1 This diagram illustrates the silicon wafer thickness from the head to the tail of the silicon rod after cutting using an existing slotted wheel in a reverse slitting process. The horizontal axis represents the wafer's serial number, indicating its position, and the vertical axis represents the wafer's thickness. Figure 1 As can be seen, there is a significant difference in silicon wafer thickness. This is because the diamond wire wears down continuously as it enters from one end of the single crystal during the cutting process, until it exits from the other end. Throughout the cutting process, as the wear on the surface particles of the diamond wire increases, the height of the surface particles decreases, leading to a gradual reduction in the effective wire diameter. Since silicon wafer thickness is typically equal to the slot spacing minus the wire diameter, and the slot spacing remains constant, the silicon wafer thickness gradually increases as the effective wire diameter decreases. This means that the silicon wafer cut at the end gradually becomes thicker, resulting in a significant difference in silicon wafer thickness and affecting the uniformity of the wafer thickness. Furthermore, the thicker silicon wafer cut at the end also leads to a waste of raw materials. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a grooved wheel and a wire cutting machine equipped with the grooved wheel, which effectively solves the technical problem that wear caused by diamond wire during the cutting process affects the uniformity of silicon wafer thickness and causes waste of raw materials, thus overcoming the shortcomings of the prior art.

[0005] The technical solution adopted by this utility model is: a grooved wheel, wherein a wiring groove is provided on the grooved wheel along the axial direction, the grooved wheel includes a first end and a second end, and the groove spacing between adjacent wiring grooves at the first end is greater than the groove spacing between adjacent wiring grooves at the second end.

[0006] Furthermore, the spacing between adjacent wiring slots at the first end is S1, and the spacing between adjacent wiring slots at the second end is S2, with the difference between S1 and S2 being 1 to 2 μm.

[0007] Furthermore, along the direction from the first end to the second end, the spacing between adjacent wiring slots decreases linearly or non-linearly.

[0008] Furthermore, along the direction from the first end to the second end, the wiring groove includes a first segment, a second segment, and a third segment. The average groove spacing between adjacent wiring grooves in the first segment is D1, the average groove spacing between adjacent wiring grooves in the second segment is D2, and the average groove spacing between adjacent wiring grooves in the third segment is D3, where D1≥D2>D3 or D1>D2≥D3.

[0009] Furthermore, when D1 > D2 > D3, the difference between D1 and D2 is 0.5–0.7 μm, and the difference between D2 and D3 is 0.8–1 μm.

[0010] Furthermore, the width of the second-end wiring groove is greater than the width of the first-end wiring groove.

[0011] Furthermore, the width of the first end wiring groove is S3, and the width of the second end wiring groove is S4, with the difference between S3 and S4 being 3-15μm.

[0012] Furthermore, the wiring groove can be symmetrical or asymmetrical.

[0013] Furthermore, the wiring trough is an asymmetrical wiring trough; along the direction from the first segment to the second end, the wiring trough includes a first sidewall and a second sidewall, the angle between the first sidewall and the central axis of the bottom of the wiring trough is α1, and the angle between the second sidewall and the central axis of the wiring trough is α2, wherein α1 > α2.

[0014] This utility model also provides a wire cutting machine, including the grooved wheel as described above.

[0015] The advantages and positive effects of this utility model are as follows: By adopting the above technical solution, the technical problem of material waste caused by the wear of diamond wire during the cutting process, which makes it difficult to keep the effective wire diameter constant and affects the uniformity of silicon wafer thickness, is effectively solved. This reduces the difference in silicon wafer thickness, improves the uniformity of silicon wafer thickness, enhances silicon wafer quality, increases the number of wafers produced by cutting, reduces material waste, and reduces wire skipping abnormalities. Attached Figure Description

[0016] The above and other objects, features, and advantages of this utility model will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this utility model and form part of the specification. They are used together with the embodiments of this utility model to explain the utility model and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same parts or steps.

[0017] Figure 1 This is a schematic diagram of the thickness of silicon wafers cut by slotted wheels with equal slot spacing using existing technology.

[0018] Figure 2 This is a schematic diagram of the thickness of a silicon wafer cut by a grooved wheel according to an embodiment of this utility model.

[0019] Figure 3 This is a schematic diagram of the structure of a grooved wheel according to one embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the structure of a grooved wheel according to Embodiment 2 of this utility model.

[0021] Figure 5 This is a schematic diagram of the structure of a grooved wheel according to Embodiment 3 of this utility model.

[0022] Figure 6 This is a schematic diagram of the structure of a grooved wheel according to Embodiment 4 of this utility model.

[0023] In the picture:

[0024] 1. Geneva wheel body; 2. Wiring groove; 3. Cutting line.

[0025] 4. First end 5. Second end Detailed Implementation

[0026] This utility model provides a grooved wheel and a wire cutting machine equipped with the grooved wheel. The technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0027] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0028] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0029] When using expressions such as "at least one of A, B, and C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C. Similarly, when using expressions such as "at least one of A, B, or C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C.

[0030] It should also be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of this disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding this disclosure.

[0031] like Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, an embodiment of this utility model discloses a grooved wheel, including a grooved wheel body 1, on which wiring grooves 2 are formed. The groove spacing is the distance between the central axes of the bottom of the wiring grooves. A cutting wire 3 is wound around the wiring groove 2. The grooved wheel includes a first end 4 and a second end 5, with the cutting wire 3 entering at the first end and exiting at the second end. As the cutting wire 3 wears down from the first end 4 to the second end 5, the effective wire diameter of the cutting wire 3 decreases, resulting in an increase in the thickness of the silicon wafer after cutting at the second end 5. To ensure the uniformity of the silicon wafer thickness, the groove spacing between adjacent wiring grooves at the first end 4 is greater than the groove spacing between adjacent wiring grooves at the second end 5. During the cutting process, as the effective wire diameter at the second end 5 decreases, the groove spacing also decreases, thereby reducing the difference in silicon wafer thickness and improving the uniformity of silicon wafer thickness. Figure 2 As shown.

[0032] Specifically, the spacing between adjacent wiring slots at the first end 4 is S1, and the spacing between adjacent wiring slots at the second end 5 is S2. The difference between S1 and S2 is 1 to 2 μm. The smaller the diameter of the cutting wire 3, the less wear on the cutting wire, and the smaller the difference between S1 and S2. Conversely, the larger the diameter of the cutting wire 3, the more wear on the cutting wire, and the larger the difference between S1 and S2.

[0033] Specifically, along the direction from the first end 4 to the second end 5, the spacing between adjacent wiring slots decreases linearly or non-linearly.

[0034] In some embodiments, the spacing between adjacent wiring slots decreases linearly along the direction from the first end 4 to the second end 5. The difference in spacing between adjacent wiring slots 2 is set as a grooving coefficient, which is a fixed value. A fixed grooving coefficient is set based on the target wafer thickness and the wire diameter of the cutting line 3. The initial spacing is the set spacing. From the first end 4 to the second end 5, the spacing decreases continuously with the grooving coefficient based on the set spacing, so that the spacing decreases gradually with the effective wire diameter in an arithmetic progression, thereby ensuring the uniformity of the silicon wafer thickness.

[0035] In some embodiments, the spacing between adjacent wiring slots decreases non-linearly along the direction from the first end 4 to the second end 5. The wiring slot along the direction from the first end 4 to the second end 5 includes a first segment, a second segment, and a third segment. The lengths of the first, second, and third segments can be the same or different. The spacing between adjacent wiring slots in the first segment can be the same or different, with an average spacing of D1. The spacing between adjacent wiring slots in the second segment can also be the same or different, with an average spacing of D2. The spacing between adjacent wiring slots in the third segment can also be the same or different, with an average spacing of D3. Wear during the cutting process is non-linear. The first segment is the inlet end, with less wear and a larger average spacing; the third segment is the outlet end, with greater wear and a smaller average spacing, which to some extent solves the problem of uneven silicon wafer thickness. If the cutting line is thin, with a diameter of 28–30 μm, the wear is less, and in this case, D1 = D2 > D3, with the difference between D1 and D3 set to 1.1–1.5 μm. If the cutting wire diameter is medium, between 31 and 36 μm, and the wear is moderate, then D1 > D2 > D3, with the difference between D1 and D2 being 0.5–0.7 μm and the difference between D2 and D3 being 0.8–1 μm. If the cutting wire is thicker, between 37 and 40 μm, and the wear is greater, then D1 > D2 = D3, with the difference between D1 and D3 being 1.5–2.0 μm. Optionally, the width of the slot in the second end 5 is greater than the width of the slot in the first end 4. Since the spacing between adjacent slots in the second end 5 is smaller than that between adjacent slots in the first end 4, the cutting wire is prone to skipping when it is in the second end 5. Therefore, increasing the width of the slot in the second end 5 prevents skipping. Preferably, the width of the slot in the first end 4 is S3, and the width of the slot in the second end 5 is S4, with the difference between S3 and S4 being 5–15 μm.

[0036] The slot ridge is the raised portion between adjacent wiring slots. The width of the slot ridge changes in accordance with the change in the slot spacing. When the slot spacing between adjacent wiring slots decreases linearly, the width of the slot ridge increases linearly. When the slot spacing between adjacent wiring slots decreases non-linearly, if the slot spacing between adjacent wiring slots is equal, the width of the slot ridge remains unchanged; if the slot spacing between adjacent wiring slots decreases, the width of the slot ridge increases.

[0037] Specifically, the wiring trough can be symmetrical or asymmetrical. Preferably, the wiring trough is asymmetrical, meaning the angles between the two side walls and the central axis of the trough bottom are different. Along the direction from the first end to the second end, the wiring trough includes a first side wall and a second side wall. The angle between the first side wall and the central axis of the wiring trough is α1, and the angle between the second side wall and the central axis of the wiring trough is α2, where α1 > α2. The ratio of α1 to α2 is set to 1.5:1 to 1:1. The angle α1 near the first end 4 is set to 15–22.5°, and the angle α2 near the second end 5 is set to 15–20°. Because the spacing between adjacent wiring troughs at the second end 5 is small, the cutting line is prone to skipping towards the end with the smaller spacing. The larger angle near the first end 4 helps prevent skipping. The shape of the wiring trough is not limited.

[0038] This application effectively solves the jumper problem by setting the slot spacing between adjacent wiring slots at the first end and the slot spacing between adjacent wiring slots at the second end, and by adjusting the slot width and the slot shape of the wiring slots, thereby ensuring the uniformity of the cut silicon wafers.

[0039] A wire cutting machine includes a grooved wheel as described above, which is mounted on the roller frame of the wire cutting machine using bearings. The grooved wheel includes a wheel body 1, on which a wire cutting groove 2 is formed. A cutting wire 3 is wound around the wire cutting groove 2. The grooved wheel includes a first end 4 and a second end 5, with the cutting wire 3 entering at the first end 4 and exiting at the second end 5. The groove spacing between adjacent wire cutting grooves at the first end 4 is greater than the groove spacing between adjacent wire cutting grooves at the second end 5. The first end is the wire inlet end, and the second end is the wire outlet end.

[0040] Comparative Example: A grooved wheel includes a grooved wheel body 1, on which wiring grooves 2 are formed. The wiring grooves 2 have a single V-shaped structure, which is symmetrical. The bottom of the groove is set to be arc-shaped, and the opening angle is 40°. The wiring grooves 2 are arranged at equal intervals along the axis of the grooved wheel body 1, and the groove spacing is set to 170μm.

[0041] A silicon rod with a length of 850 mm was cut, with a cutting line diameter of 33 μm, resulting in 4941 silicon wafers. The thickness of the silicon wafers at the head of the rod was 129.64 μm, while the thickness at the tail was 130.9 μm, with a thickness difference of 1.26 μm between the two ends, indicating a significant difference in wafer thickness.

[0042] Example 1: As Figure 3 As shown, a grooved wheel includes a grooved wheel body 1 with wiring grooves 2 formed on it. The grooved wheel includes a first end 4 and a second end 5, with a cutting line 3 entering at the first end 4 and exiting at the second end 5. Along the direction from the first end 4 to the second end 5, the spacing between adjacent wiring grooves decreases linearly. The initial spacing between the grooves at the first end 4 is 171.5 μm, and the grooving coefficient is set to a fixed value of 0.003 μm. The difference between the spacing between adjacent wiring grooves at the first end 4 and the second end 5 is 1.3 μm. The initial groove width at the first end 4 is 54.3 μm, and the groove width increases linearly with the spacing between grooves. The difference between adjacent groove widths is 0.026 μm, and the groove width at the first end 4 is 13 μm smaller than the groove width at the second end 5. The wiring trough has a single V-shaped asymmetrical structure with an arc-shaped bottom. Along the direction from the first section to the second end, the wiring trough includes a first sidewall and a second sidewall. The angle between the first sidewall and the central axis of the bottom of the wiring trough is α1, and the angle between the second sidewall and the central axis of the bottom of the wiring trough is α2, where α1 > α2.

[0043] A silicon rod with a length of 850 mm was cut, with a cutting line diameter of 33 μm, resulting in 4956 silicon wafers, 0.29% more than in Example 1. The silicon wafer thickness at the head of the rod was 129.98 μm, and the silicon wafer thickness at the tail was 130.2 μm, with a thickness difference of 0.22 μm between the head and tail. The wafer thickness was more uniform, and the skipped wire rate was 5.7% (5 skipped wires per 100 cuts).

[0044] Example 2: Figure 4 As shown, a grooved wheel includes a grooved wheel body 1, on which wiring grooves 2 are formed. The grooved wheel includes a first end 4 and a second end 5, and a cutting line 3 cuts into the first end 4 and exits at the second end 5. Along the direction from the first end 4 to the second end 5, the spacing between adjacent wiring grooves decreases non-linearly. Along the direction from the first end 4 to the second end 5, the wiring groove includes a first segment, a second segment, and a third segment. The first segment, the second segment, and the third segment have the same length. The spacing D1 between adjacent wiring grooves in the first segment is the same, the spacing D2 between adjacent wiring grooves in the second segment is the same, and the spacing D3 between adjacent wiring grooves in the third segment is the same. D1 = D2 = 171.5 μm, D3 = 170.2 μm. The groove width of the first segment and the second segment is the same at 54.2 μm, and the groove width of the third segment is 60.2 μm. The wiring trough has a single V-shaped asymmetrical structure with an arc-shaped bottom. Along the direction from the first section to the second end, the wiring trough includes a first sidewall and a second sidewall. The angle between the first sidewall and the central axis of the bottom of the wiring trough is α1, and the angle between the second sidewall and the central axis of the bottom of the wiring trough is α2, where α1 > α2.

[0045] A silicon ingot with a length of 850 mm was cut, with a cutting line diameter of 30 μm, yielding a total of 4941 silicon wafers. The wafer thickness at the head of the ingot was 129.8 μm, and the wafer thickness at the tail was 130.0 μm, with a thickness difference of 0.2 μm between the two ends, resulting in more uniform wafer thickness. The jumper rate was 4.8%.

[0046] Example 3: Figure 5 As shown, a grooved wheel includes a grooved wheel body 1, on which wiring grooves 2 are formed. The grooved wheel includes a first end 4 and a second end 5, and a cutting line 3 cuts into the first end 4 and exits at the second end 5. Along the direction from the first end 4 to the second end 5, the spacing between adjacent wiring grooves decreases non-linearly. Along the direction from the first end 4 to the second end 5, the wiring groove includes a first segment, a second segment, and a third segment. The first segment, the second segment, and the third segment have the same length. The spacing D1 between adjacent wiring grooves in the first segment is the same, the spacing D2 between adjacent wiring grooves in the second segment is the same, and the spacing D3 between adjacent wiring grooves in the third segment is the same. D1 = 171.5 μm, D2 = 170.9 μm, D3 = 170.0 μm. The groove width of the first segment is 52.4 μm, the groove width of the second segment is 55.4 μm, and the groove width of the third segment is 62.4 μm. The wiring trough 2 has a single V-shaped asymmetrical structure with an arc-shaped bottom. Along the direction from the first section to the second end, the wiring trough includes a first sidewall and a second sidewall. The angle between the first sidewall and the central axis of the bottom of the wiring trough is α1, and the angle between the second sidewall and the central axis of the bottom of the wiring trough is α2, where α1 > α2.

[0047] A silicon ingot with a length of 850 mm was cut, with a cutting line diameter of 3 of 36 μm, resulting in 4899 silicon wafers. The wafer thickness at the head of the ingot was 129.97 μm, and the wafer thickness at the tail (5) was 130.22 μm, with a thickness difference of 0.25 μm between the two ends, resulting in more uniform wafer thickness. The jumper rate was 5.2%.

[0048] Example 4: Figure 6As shown, a grooved wheel includes a grooved wheel body 1, on which wiring grooves 2 are formed. The grooved wheel includes a first end 4 and a second end 5, and a cutting line 3 cuts into the first end 4 and exits at the second end 5. Along the direction from the first end 4 to the second end 5, the spacing between adjacent wiring grooves decreases non-linearly. Along the direction from the first end 4 to the second end 5, the wiring groove includes a first segment, a second segment, and a third segment. The first segment, the second segment, and the third segment have the same length. The spacing D1 between adjacent wiring grooves in the first segment is the same, the spacing D2 between adjacent wiring grooves in the second segment is the same, and the spacing D3 between adjacent wiring grooves in the third segment is the same. D1 = 171.7 μm, D2 = D3 = 170.0 μm, the groove width of the first segment is 52.4 μm, and the groove width of the second segment is equal to the groove width of the third segment, which is 62.4 μm. The wiring trough 2 has a single V-shaped asymmetrical structure with an arc-shaped bottom. Along the direction from the first section to the second end, the wiring trough includes a first sidewall and a second sidewall. The angle between the first sidewall and the central axis of the bottom of the wiring trough is α1, and the angle between the second sidewall and the central axis of the bottom of the wiring trough is α2, where α1 > α2.

[0049] A silicon ingot with a length of 850 mm was cut, with a cutting line diameter of 3 of 38 μm, resulting in 4880 silicon wafers. The wafer thickness at the head of the ingot was 129.90 μm, and the wafer thickness at the tail (5) was 130.12 μm, with a thickness difference of 0.22 μm between the two ends, resulting in more uniform wafer thickness. The jumper rate was 4.5%.

[0050] The technical solution adopted in this utility model is:

[0051] It effectively solves the technical problem that wear caused by diamond wire during the cutting process makes it difficult to maintain a constant effective wire diameter, affecting the uniformity of silicon wafer thickness and causing material waste. It reduces the difference in silicon wafer thickness, improves the uniformity of silicon wafer thickness, enhances silicon wafer quality, increases the number of wafers produced by cutting, reduces material waste, and prevents wire skipping abnormalities.

[0052] The embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. It should be noted that implementations not illustrated or described in the drawings or the main text of the specification are forms known to those skilled in the art and have not been described in detail. Furthermore, the definitions of the various components described above are not limited to the specific structures, shapes, or methods mentioned in the embodiments, and those skilled in the art can easily modify or substitute them.

[0053] The embodiments of this utility model have been described in detail above, but the content described is only a preferred embodiment of this utility model and should not be considered as limiting the scope of implementation of this utility model. All equivalent changes and improvements made in accordance with the claims of this utility model should still fall within the patent coverage of this utility model.

Claims

1. A Geneva wheel, characterized in that: The grooved wheel has wiring grooves along its axial direction. The grooved wheel includes a first end and a second end. The groove spacing between adjacent wiring grooves at the first end is greater than the groove spacing between adjacent wiring grooves at the second end.

2. The Geneva wheel according to claim 1, characterized in that: The spacing between adjacent wiring slots at the first end is S1, and the spacing between adjacent wiring slots at the second end is S2. The difference between S1 and S2 is 1 to 2 μm.

3. The Geneva wheel according to any one of claims 1 or 2, characterized in that: Along the direction from the first end to the second end, the spacing between adjacent wiring slots decreases linearly or non-linearly.

4. The Geneva wheel according to claim 3, characterized in that: Along the direction from the first end to the second end, the wiring groove includes a first segment, a second segment, and a third segment. The average groove spacing between adjacent wiring grooves in the first segment is D1, the average groove spacing between adjacent wiring grooves in the second segment is D2, and the average groove spacing between adjacent wiring grooves in the third segment is D3, where D1≥D2>D3 or D1>D2≥D3.

5. The Geneva wheel according to claim 4, characterized in that: When D1 > D2 > D3, the difference between D1 and D2 is 0.5–0.7 μm, and the difference between D2 and D3 is 0.8–1 μm.

6. The Geneva wheel according to any one of claims 1-2 and 4-5, characterized in that: The width of the second-end wiring groove is greater than the width of the first-end wiring groove.

7. The Geneva wheel according to claim 6, characterized in that: The width of the first end wiring groove is S3, and the width of the second end wiring groove is S4. The difference between S3 and S4 is 5-15μm.

8. The Geneva wheel according to any one of claims 1-2 and 4-5, characterized in that: The wiring trough can be symmetrical or asymmetrical.

9. The Geneva wheel according to claim 8, characterized in that: The wiring channel is an asymmetrical wiring channel; Along the direction from the first end to the second end, the wiring groove includes a first sidewall and a second sidewall. The angle between the first sidewall and the central axis of the bottom of the wiring groove is α1, and the angle between the second sidewall and the central axis of the bottom of the wiring groove is α2, wherein α1 > α2.

10. A wire cutting machine, characterized in that: Includes the Geneva wheel as described in any one of claims 1-9.

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