Wafer film cutting device and film cutting system

Abstract

The utility model provides a wafer film cutting device and a film cutting system. The wafer film cutting device comprises a base and an anti-rolling adsorption ring groove, the base is used for placing a wafer with a covering film attached to the surface, and a film cutting ring groove matched with the cutting tool is formed in the surface of the base; the anti-rolling adsorption ring groove is formed in the surface of the base and located on the inner side of the film cutting ring groove, and the anti-rolling adsorption ring groove is constructed to be capable of adsorbing a covering film on the surface of the wafer through vacuumizing; the anti-rolling adsorption ring groove and the film cutting ring groove surround a wafer arranged on the base and correspond to the peripheral part, exceeding the edge of the wafer, of the covering film. Based on the technical scheme of the utility model, even if the edge of the film is retracted and curled after film cutting, the anti-curl adsorption ring groove can adsorb the part of the film on the periphery of the edge of the wafer so as not to generate curled edges, thereby preventing disturbance generated by the retraction and curled edges of the edge of the film from reaching the wafer. Therefore, the problem that the bare crystal at the edge of the wafer falls off is avoided, and the yield of the wafer is ensured.

Description

Technical Field

[0001] This utility model relates to the field of chip manufacturing technology, and in particular to a wafer cutting device and cutting system. Background Technology

[0002] Power devices primarily utilize two forms: IGBTs and MOSFETs. However, IGBTs are better suited for high-voltage applications, as silicon-based MOSFETs cannot meet such high demands. The conventional approach is to modify the MOSFET material to achieve high-voltage, high-current applications. Silicon-based IGBTs dominate high-voltage, high-current scenarios, but they cannot withstand high-frequency conditions and have high power consumption. SiC, due to its high-voltage and high-temperature resistance, allows it to achieve the same voltage withstand capability as silicon-based IGBTs using simpler MOSFET devices, while avoiding their high energy consumption. Under the same conditions, silicon carbide MOSFETs reduce energy loss by 66% compared to silicon-based IGBTs of the same specifications, primarily due to a significant reduction in switching losses. In the new energy vehicle industry, SiC can be used in inverters for driving and controlling motors, on-board chargers, and fast-charging piles. In photovoltaic power generation, leading photovoltaic inverter companies have already adopted SiC power devices to replace silicon devices.

[0003] In the manufacturing process of SiC-MOS or IGBT devices, the traditional dicing process involves dicing through the entire wafer in one go. Due to the extremely high hardness of SiC material, the dicing cost is very high, and the edge chipping is large, resulting in a dicing width of about 80um, which wastes the usable area of ​​the wafer.

[0004] To address this issue, laser scribing and dicing processes can effectively overcome the shortcomings of traditional cutting processes. However, after scribing, these processes require further film expansion and casting. During the casting process, the film is stretched due to the previous film expansion. Once the casting is completed, the film shrinks under stress, resulting in curled edges and causing the edge bands to fall off, which affects the yield. Utility Model Content

[0005] To address the problem of edge die loss caused by inward shrinkage and curling of the wafer film after dicing in the existing wafer cutting process, this invention proposes a wafer cutting device and cutting system.

[0006] In a first aspect, the present invention provides a wafer cutting device, comprising:

[0007] A base for holding a wafer with a film-coated surface, the base surface having a cutting groove for engaging a cutting tool; and

[0008] An anti-winding adsorption ring groove is constructed on the surface of the base and located inside the cutting ring groove. The anti-winding adsorption ring groove is configured to adsorb the coating on the wafer surface by vacuuming.

[0009] The anti-winding adsorption ring groove and the film cutting ring groove both surround the wafer placed on the base, and both correspond to the outer portion of the coating that extends beyond the edge of the wafer.

[0010] In one embodiment, there are multiple anti-winding adsorption ring grooves, the centers of the multiple anti-winding adsorption ring grooves are concentric, and the diameters of the multiple anti-winding adsorption ring grooves are different.

[0011] In one embodiment, the ring widths of the plurality of anti-winding adsorption ring grooves are not completely equal, and the ring width of the anti-winding adsorption ring grooves radially closer to the wafer is greater than the ring width of the anti-winding adsorption ring grooves radially farther away from the wafer.

[0012] In one embodiment, the ratio of the minimum ring width to the maximum ring width in the plurality of anti-winding adsorption ring grooves ranges from 1:1.5 to 1:3, and the depth of the anti-winding adsorption ring groove is greater than its ring width.

[0013] In one embodiment, the base is further provided with a peripheral main adsorption ring groove, which is located between the cutting ring groove and the outermost anti-winding adsorption ring groove. A plurality of anti-winding adsorption ring grooves are radially evenly distributed in the area between the peripheral main adsorption ring groove and the wafer edge.

[0014] In one embodiment, the ring widths of the plurality of anti-winding adsorption ring grooves are not completely equal, and the ring width of the outer main adsorption ring groove is greater than the minimum ring width among the plurality of anti-winding adsorption ring grooves and less than the maximum ring width among the plurality of anti-winding adsorption ring grooves.

[0015] In one embodiment, the base is further provided with at least one inner main adsorption ring groove and at least one radial adsorption groove, the inner main adsorption ring groove corresponding to the wafer, and the radial adsorption groove sequentially connecting each of the inner main adsorption ring grooves and the outer main adsorption ring grooves in the radial direction.

[0016] In one embodiment, alignment marks are provided on the surface of the base, and the shape of the alignment marks is the same as the shape of the positioning edge of the wafer.

[0017] In one embodiment, the base is further provided with a vacuum channel, which connects to each adsorption ring groove on the base, and the vacuum channel is connected to a vacuum pumping device via a pipeline.

[0018] Secondly, the present invention provides a wafer cutting system, which includes the aforementioned wafer cutting device, and thus possesses all the technical effects it possesses.

[0019] The above-mentioned technical features can be combined in various suitable ways or replaced by equivalent technical features, as long as the purpose of this utility model can be achieved.

[0020] The wafer cutting device and cutting system provided by this utility model have at least the following advantages compared with the prior art:

[0021] This invention relates to a wafer cutting device and system. An anti-rolling adsorption groove is constructed on the base of the wafer cutting device to adsorb the outer portion of the film extending beyond the wafer edge. Based on the positional relationship and cooperation between the anti-rolling adsorption groove and the cutting groove, even if the edge of the central part of the film retracts or curls after cutting, the presence of the anti-rolling adsorption groove can adsorb the portion of the film located outside the wafer edge, preventing it from curling. This avoids disturbances caused by the retraction and curling of the film edge reaching the wafer, thus preventing the bare die from falling off the wafer edge and ensuring wafer yield. Attached Figure Description

[0022] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings. Wherein:

[0023] Figure 1 A top view shows the overall structure of the base portion of the wafer cutting device of this utility model;

[0024] Figure 2 A partial schematic diagram (top view) of the adsorption groove on the base surface of the wafer cutting device of this invention is shown;

[0025] Figure 3 This diagram shows the connection between the vacuum channel inside the base of the wafer cutting device of this invention and the vacuum pumping equipment.

[0026] Figure 4 This shows a partial cross-sectional view of the adsorption groove on the base of the wafer cutting device of this invention;

[0027] Figure 5 The flowchart shows the wafer cutting device of this utility model and the corresponding film expansion and casting process.

[0028] Figure 6 This diagram illustrates the principle of the wafer cutting device of this invention and the corresponding film expansion process.

[0029] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.

[0030] Figure label:

[0031] 1-Base, 11-Alignment mark, 2-Adsorption structure, 21-Anti-winding adsorption ring groove, 22-Outer main adsorption ring groove, 23-Inner main adsorption ring groove, 24-Radial adsorption groove, 3-Vacuum channel, 31-Control valve, 4-Cut film ring groove, 5-Wafer, 6-Mother and daughter rings, 7-Iron breakage ring, 71-Positioning pin, 8-Vacuum pumping equipment. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings.

[0033] Example 1

[0034] An embodiment of this utility model provides a wafer cutting device, which includes a base 1 and an anti-winding adsorption groove 21. The base 1 is used to place a wafer 5 with a film coating on its surface. The surface of the base 1 is constructed with a cutting groove 4 for cooperating with a cutting tool. The anti-winding adsorption groove 21 is constructed on the surface of the base 1 and located inside the cutting groove 4. The anti-winding adsorption groove 21 is constructed to adsorb the film coating on the surface of the wafer 5 by vacuuming.

[0035] Among them, the anti-winding adsorption ring groove 21 and the film cutting ring groove 4 are both placed around the wafer 5 on the base 1, and both correspond to the outer part of the film that extends beyond the edge of the wafer 5.

[0036] Specifically, after coating, wafer 5 first undergoes film expansion, the principle of which is shown in the attached figure. Figure 6 As shown, film expansion, in principle, involves stretching the coating to increase its area. This stretching process allows the multiple dies (die, a small piece of wafer 5 separated from wafer 5) obtained after dicing to move relative to each other, increasing the distance between adjacent dies and facilitating subsequent processes. After the film expansion process, the casting process can then proceed.

[0037] Before the lamination process, the edges of the coating are cut to separate the central portion of the wafer 5 on the coating, thus facilitating subsequent processing steps. During the expansion process, the coating is stretched and has the potential for elastic contraction. Once the edges of the coating are cut, the edges of the separated central portion will contract under their own elasticity, resulting in curling. This can easily cause the bare die near the coating edge to fall off (i.e., the die drop mentioned in the background section).

[0038] The wafer cutting device of this utility model is shown in the attached figure. Figure 1As shown, the main body is a base 1, which is used to place and position the coated wafer 5. Specifically, the back side of the wafer 5 that contacts the surface of the base 1 has the coating. A cutting groove 4 and an anti-winding adsorption groove 21 are constructed on the base 1. The cutting groove 4 is used to cooperate with a cutting tool to define the cutting path of the tool for cutting the coating. The anti-winding adsorption groove 21 can adsorb the outer portion of the coating that extends beyond the edge of the wafer 5. The anti-winding adsorption groove 21 surrounds the wafer 5 placed on the surface of the base 1, and the cutting groove 4 is located further outward from the anti-winding adsorption groove 21. Based on this design, when the cutting tool is inserted into the cutting ring groove 4 to cut the outer part of the coating in the circumferential direction, even if the edge of the center part of the coating retracts or curls after cutting, the presence of the anti-curling adsorption ring groove 21 can adsorb the part of the coating located on the outer edge of the wafer 5, preventing it from curling. This avoids the disturbance caused by the retraction and curling of the coating edge from reaching the wafer 5, thereby preventing the bare die at the edge of the wafer 5 from falling off due to the disturbance of the coating retraction and curling, and ensuring the yield of the wafer 5.

[0039] Furthermore, there are multiple anti-winding adsorption ring grooves 21, with the centers of the multiple anti-winding adsorption ring grooves 21 being concentric and the diameters of the multiple anti-winding adsorption ring grooves 21 being different.

[0040] Specifically, the number of anti-winding adsorption ring grooves 21 can be determined according to requirements, as shown in the attached diagram. Figure 1 In this embodiment, there are two anti-roll-up adsorption grooves 21. The centers of the two anti-roll-up adsorption grooves 21 are at the same point (in this embodiment, the center of the anti-roll-up adsorption groove 21 is located at the center of the surface of the base 1), that is, concentric, and the diameters of the two anti-roll-up adsorption grooves 21 are different. The two anti-roll-up adsorption grooves 21 can adsorb different parts of the coating edge in the radial direction, forming two lines of defense to prevent edge rolling disturbance from reaching the wafer 5, thereby improving the anti-roll-up effect.

[0041] Optionally, if the anti-winding adsorption ring groove 21 is set to a circular shape, then the multiple anti-winding adsorption ring grooves 21 are distributed in the form of concentric circles.

[0042] Furthermore, the ring widths of the multiple anti-winding adsorption ring grooves 21 are not completely equal, and the ring width of the anti-winding adsorption ring groove 21 that is closer to the wafer 5 in the radial direction is greater than the ring width of the anti-winding adsorption ring groove 21 that is farther away from the wafer 5 in the radial direction.

[0043] Specifically, for multiple anti-winding adsorption ring grooves 21, they can adopt completely different ring widths. In the radially outward direction, the ring width of the anti-winding adsorption ring groove 21 decreases sequentially. Of course, for multiple anti-winding adsorption ring grooves 21, their ring widths can also be partially the same. For example, the innermost anti-winding adsorption ring groove 21 closest to the wafer 5 has the widest ring width, and the outermost anti-winding adsorption ring groove 21 furthest from the wafer 5 has the narrowest ring width. The ring widths of the other anti-winding adsorption ring grooves 21 located between the innermost and outermost ring grooves can be equal.

[0044] In this embodiment, as shown in the attached figure... Figure 1 As shown in the attached figure, there are two anti-winding adsorption ring grooves 21. The inner anti-winding adsorption ring groove 21 closer to the wafer 5 has a wider ring width, while the outer anti-winding adsorption ring groove 21 farther from the wafer 5 has a narrower ring width. Figure 4 As shown. The purpose of this design is that the outer anti-roll adsorption groove 21, due to its narrower ring width, can generate a greater adsorption force, quickly and forcefully adsorbing the edge of the coating; while the inner anti-roll adsorption groove 21, with its wider ring width, can form a larger adsorption area, further consolidating the adsorption stability of the coating near the inner part of the wafer 5. The combination of the two widths of the anti-roll adsorption groove 21 can effectively prevent the edge of the cut coating center portion from shrinking and curling, thus preventing the edge die from falling off during the casting process.

[0045] Optionally, the ratio of the minimum to the maximum ring width among the plurality of anti-winding adsorption ring grooves 21 ranges from 1:1.5 to 1:3, and the depth of the anti-winding adsorption ring groove 21 is greater than its ring width. Further optionally, the minimum ring width of the anti-winding adsorption ring groove 21 ranges from 0.4 mm to 0.8 mm, the maximum ring width ranges from 0.6 mm to 1.2 mm, and the depth of the anti-winding adsorption ring groove 21 ranges from 1 mm to 5 mm.

[0046] In this embodiment, the width of the inner anti-winding adsorption ring groove 21 ranges from 0.6 mm to 1.2 mm, and the width of the outer anti-winding adsorption ring groove 21 ranges from 0.4 mm to 0.8 mm. The two grooves have the same depth, which ranges from 1 mm to 5 mm.

[0047] Example 2

[0048] An embodiment of this utility model provides a wafer cutting device, which includes a base 1 and an anti-winding adsorption groove 21. The base 1 is used to place a wafer 5 with a film coating on its surface. The surface of the base 1 is constructed with a cutting groove 4 for cooperating with a cutting tool. The anti-winding adsorption groove 21 is constructed on the surface of the base 1 and located inside the cutting groove 4. The anti-winding adsorption groove 21 is constructed to adsorb the film coating on the surface of the wafer 5 by vacuuming.

[0049] Among them, the anti-winding adsorption ring groove 21 and the film cutting ring groove 4 are both placed around the wafer 5 on the base 1, and both correspond to the outer part of the film that extends beyond the edge of the wafer 5.

[0050] Specifically, after coating, wafer 5 first undergoes film expansion, the principle of which is shown in the attached figure. Figure 6 As shown, film expansion, in principle, involves stretching the coating to increase its area. This stretching process allows the multiple dies (die, a small piece of wafer 5 separated from wafer 5) obtained after dicing to move relative to each other, increasing the distance between adjacent dies and facilitating subsequent processes. After the film expansion process, the casting process can then proceed.

[0051] Before the lamination process, the edges of the coating are cut to separate the central portion of the wafer 5 on the coating, thus facilitating subsequent processing steps. During the expansion process, the coating is stretched and has the potential for elastic contraction. Once the edges of the coating are cut, the edges of the separated central portion will contract under their own elasticity, resulting in curling. This can easily cause the bare die near the coating edge to fall off (i.e., the die drop mentioned in the background section).

[0052] The wafer cutting device of this utility model is shown in the attached figure. Figure 1 As shown, the main body is a base 1, which is used to place and position the coated wafer 5. Specifically, the back side of the wafer 5 that contacts the surface of the base 1 has the coating. A cutting groove 4 and an anti-winding adsorption groove 21 are constructed on the base 1. The cutting groove 4 is used to cooperate with a cutting tool to define the cutting path of the tool for cutting the coating. The anti-winding adsorption groove 21 can adsorb the outer portion of the coating that extends beyond the edge of the wafer 5. The anti-winding adsorption groove 21 surrounds the wafer 5 placed on the surface of the base 1, and the cutting groove 4 is located further outward from the anti-winding adsorption groove 21. Based on this design, when the cutting tool is inserted into the cutting ring groove 4 to cut the outer part of the coating in the circumferential direction, even if the edge of the center part of the coating retracts or curls after cutting, the presence of the anti-curling adsorption ring groove 21 can adsorb the part of the coating located on the outer edge of the wafer 5, preventing it from curling. This avoids the disturbance caused by the retraction and curling of the coating edge from reaching the wafer 5, thereby preventing the bare die at the edge of the wafer 5 from falling off due to the disturbance of the coating retraction and curling, and ensuring the yield of the wafer 5.

[0053] Furthermore, there are multiple anti-winding adsorption ring grooves 21, with the centers of the multiple anti-winding adsorption ring grooves 21 being concentric and the diameters of the multiple anti-winding adsorption ring grooves 21 being different.

[0054] Specifically, the number of anti-winding adsorption ring grooves 21 can be determined according to requirements, as shown in the attached diagram. Figure 1In this embodiment, there are two anti-roll-up adsorption grooves 21. The centers of the two anti-roll-up adsorption grooves 21 are at the same point (in this embodiment, the center of the anti-roll-up adsorption groove 21 is located at the center of the surface of the base 1), that is, concentric, and the diameters of the two anti-roll-up adsorption grooves 21 are different. The two anti-roll-up adsorption grooves 21 can adsorb different parts of the coating edge in the radial direction, forming two lines of defense to prevent edge rolling disturbance from reaching the wafer 5, thereby improving the anti-roll-up effect.

[0055] Optionally, if the anti-winding adsorption ring groove 21 is set to a circular shape, then the multiple anti-winding adsorption ring grooves 21 are distributed in the form of concentric circles.

[0056] Furthermore, the ring widths of the multiple anti-winding adsorption ring grooves 21 are not completely equal, and the ring width of the anti-winding adsorption ring groove 21 that is closer to the wafer 5 in the radial direction is greater than the ring width of the anti-winding adsorption ring groove 21 that is farther away from the wafer 5 in the radial direction.

[0057] Specifically, for multiple anti-winding adsorption ring grooves 21, they can adopt completely different ring widths. In the radially outward direction, the ring width of the anti-winding adsorption ring groove 21 decreases sequentially. Of course, for multiple anti-winding adsorption ring grooves 21, their ring widths can also be partially the same. For example, the innermost anti-winding adsorption ring groove 21 closest to the wafer 5 has the widest ring width, and the outermost anti-winding adsorption ring groove 21 furthest from the wafer 5 has the narrowest ring width. The ring widths of the other anti-winding adsorption ring grooves 21 located between the innermost and outermost ring grooves can be equal.

[0058] In this embodiment, as shown in the attached figure... Figure 1 As shown in the attached figure, there are two anti-winding adsorption ring grooves 21. The inner anti-winding adsorption ring groove 21 closer to the wafer 5 has a wider ring width, while the outer anti-winding adsorption ring groove 21 farther from the wafer 5 has a narrower ring width. Figure 4 As shown. The purpose of this design is that the outer anti-roll adsorption groove 21, due to its narrower ring width, can generate a greater adsorption force, quickly and forcefully adsorbing the edge of the coating; while the inner anti-roll adsorption groove 21, with its wider ring width, can form a larger adsorption area, further consolidating the adsorption stability of the coating near the inner part of the wafer 5. The combination of the two widths of the anti-roll adsorption groove 21 can effectively prevent the edge of the cut coating center portion from shrinking and curling, thus preventing the edge die from falling off during the casting process.

[0059] Optionally, the ratio of the minimum to the maximum ring width among the plurality of anti-winding adsorption ring grooves 21 ranges from 1:1.5 to 1:3, and the depth of the anti-winding adsorption ring groove 21 is greater than its ring width. Further optionally, the minimum ring width of the anti-winding adsorption ring groove 21 ranges from 0.4 mm to 0.8 mm, the maximum ring width ranges from 0.6 mm to 1.2 mm, and the depth of the anti-winding adsorption ring groove 21 ranges from 1 mm to 5 mm.

[0060] In this embodiment, the width of the inner anti-winding adsorption ring groove 21 ranges from 0.6 mm to 1.2 mm, and the width of the outer anti-winding adsorption ring groove 21 ranges from 0.4 mm to 0.8 mm. The two grooves have the same depth, which ranges from 1 mm to 5 mm.

[0061] Furthermore, the base 1 is also constructed with an outer main adsorption ring groove 22, which is located between the cutting ring groove 4 and the outermost anti-winding adsorption ring groove 21. Multiple anti-winding adsorption ring grooves 21 are evenly distributed radially in the area between the outer main adsorption ring groove 22 and the edge of the wafer 5.

[0062] Specifically, as shown in the attached diagram. Figure 1 As shown, the base 1 also has an outer main adsorption ring groove 22 located outside the outermost anti-curling adsorption ring groove 21. The outer main adsorption ring groove 22 is used to mainly adsorb and fix the coating. The outermost part of the outer main adsorption ring groove 22 is the cutting ring groove 4. There are no other adsorption structures between the outer main adsorption ring groove 22 and the cutting ring groove 4. Therefore, the curling of the coating after cutting mainly occurs in the area between the outer main adsorption ring groove 22 and the edge of the wafer 5. Therefore, to ensure the anti-curling effect, the multiple anti-curling adsorption ring grooves 21 are radially evenly distributed in the area between the outer main adsorption ring groove 22 and the edge of the wafer 5.

[0063] Furthermore, considering that the ring width of the anti-winding adsorption ring groove 21 may vary, the uniform distribution in this embodiment mainly refers to the uniformity of the approximate distribution position, and does not necessarily mean that the interval distance values ​​are exactly the same. It can also mean that the spacing is within the same value range. For example, in this embodiment, the distance between the inner anti-winding adsorption ring groove 21 and the outer anti-winding adsorption ring groove 21 is 5mm to 7mm, and the distance between the outer anti-winding adsorption ring groove 21 and the outer main adsorption ring groove 22 is 5mm to 7mm.

[0064] Furthermore, the ring widths of the multiple anti-winding adsorption ring grooves 21 are not completely equal, and the ring width of the outer main adsorption ring groove 22 is greater than the minimum ring width among the multiple anti-winding adsorption ring grooves 21 and less than the maximum ring width among the multiple anti-winding adsorption ring grooves 21.

[0065] Specifically, the ring width affects both the adsorption force and the adsorption area. For example, as mentioned above, the outer anti-roll adsorption ring groove 21, due to its narrower ring width, can generate a greater adsorption force, but its adsorption area is smaller; while the inner anti-roll adsorption ring groove 21, with its wider ring width, can generate a larger adsorption area, but its adsorption force is smaller. Therefore, for the outer main adsorption ring groove 22, which plays a major role in adsorbing the coating, it needs to balance adsorption area and adsorption force, so the ring width used is between the minimum and maximum ring width of the anti-roll adsorption ring groove 21.

[0066] Furthermore, the base 1 is also constructed with at least one inner main adsorption ring groove 23 and at least one radial adsorption groove 24. The inner main adsorption ring groove 23 corresponds to the wafer 5, and the radial adsorption groove 24 is connected in the radial direction to each inner main adsorption ring groove 23 and the outer main adsorption ring groove 22 in sequence.

[0067] Specifically, as shown in the attached diagram. Figure 1 As shown, the outer main adsorption ring groove 22 cooperates with the inner main adsorption ring groove 23 through the radial adsorption groove 24 to jointly achieve the main adsorption effect on the coating. At the same time, the radial adsorption groove 24 is also connected to each anti-roll adsorption ring groove 21, so as to achieve the overall adsorption effect. The outer main adsorption ring groove 22, the inner main adsorption ring groove 23 and the radial adsorption groove 24 have the same width and depth. The width ranges from 0.5mm to 1mm and the depth ranges from 1mm to 5mm.

[0068] In addition, please refer to the attached figure. Figure 1 In this embodiment, the base 1 has a radius of approximately 195 mm and consists of one outer main adsorption ring groove 22 and two inner main adsorption ring grooves 23. The outer main adsorption ring groove 22 has a radius of 90 mm, the innermost inner main adsorption ring groove 23 has a radius of 40 mm, and the other inner main adsorption ring groove 23 has a radius of 70 mm. The cutting ring groove 4 is located 3 mm to 4 mm from the edge of the base 1, has a depth of 1 mm to 5 mm, and a width of 0.5 mm to 1 mm.

[0069] Example 3

[0070] An embodiment of this utility model provides a wafer cutting device, which includes a base 1 and an anti-winding adsorption groove 21. The base 1 is used to place a wafer 5 with a film coating on its surface. The surface of the base 1 is constructed with a cutting groove 4 for cooperating with a cutting tool. The anti-winding adsorption groove 21 is constructed on the surface of the base 1 and located inside the cutting groove 4. The anti-winding adsorption groove 21 is constructed to adsorb the film coating on the surface of the wafer 5 by vacuuming.

[0071] Among them, the anti-winding adsorption ring groove 21 and the film cutting ring groove 4 are both placed around the wafer 5 on the base 1, and both correspond to the outer part of the film that extends beyond the edge of the wafer 5.

[0072] Specifically, after coating, wafer 5 first undergoes film expansion, the principle of which is shown in the attached figure. Figure 6 As shown, film expansion, in principle, involves stretching the coating to increase its area. This stretching process allows the multiple dies (die, a small piece of wafer 5 separated from wafer 5) obtained after dicing to move relative to each other, increasing the distance between adjacent dies and facilitating subsequent processes. After the film expansion process, the casting process can then proceed.

[0073] Before the lamination process, the edges of the coating are cut to separate the central portion of the wafer 5 on the coating, thus facilitating subsequent processing steps. During the expansion process, the coating is stretched and has the potential for elastic contraction. Once the edges of the coating are cut, the edges of the separated central portion will contract under their own elasticity, resulting in curling. This can easily cause the bare die near the coating edge to fall off (i.e., the die drop mentioned in the background section).

[0074] The wafer cutting device of this utility model is shown in the attached figure. Figure 1 As shown, the main body is a base 1, which is used to place and position the coated wafer 5. Specifically, the back side of the wafer 5 that contacts the surface of the base 1 has the coating. A cutting groove 4 and an anti-winding adsorption groove 21 are constructed on the base 1. The cutting groove 4 is used to cooperate with a cutting tool to define the cutting path of the tool for cutting the coating. The anti-winding adsorption groove 21 can adsorb the outer portion of the coating that extends beyond the edge of the wafer 5. The anti-winding adsorption groove 21 surrounds the wafer 5 placed on the surface of the base 1, and the cutting groove 4 is located further outward from the anti-winding adsorption groove 21. Based on this design, when the cutting tool is inserted into the cutting ring groove 4 to cut the outer part of the coating in the circumferential direction, even if the edge of the center part of the coating retracts or curls after cutting, the presence of the anti-curling adsorption ring groove 21 can adsorb the part of the coating located on the outer edge of the wafer 5, preventing it from curling. This avoids the disturbance caused by the retraction and curling of the coating edge from reaching the wafer 5, thereby preventing the bare die at the edge of the wafer 5 from falling off due to the disturbance of the coating retraction and curling, and ensuring the yield of the wafer 5.

[0075] Furthermore, there are multiple anti-winding adsorption ring grooves 21, with the centers of the multiple anti-winding adsorption ring grooves 21 being concentric and the diameters of the multiple anti-winding adsorption ring grooves 21 being different.

[0076] Specifically, the number of anti-winding adsorption ring grooves 21 can be determined according to requirements, as shown in the attached diagram. Figure 1 In this embodiment, there are two anti-roll-up adsorption grooves 21. The centers of the two anti-roll-up adsorption grooves 21 are at the same point (in this embodiment, the center of the anti-roll-up adsorption groove 21 is located at the center of the surface of the base 1), that is, concentric, and the diameters of the two anti-roll-up adsorption grooves 21 are different. The two anti-roll-up adsorption grooves 21 can adsorb different parts of the coating edge in the radial direction, forming two lines of defense to prevent edge rolling disturbance from reaching the wafer 5, thereby improving the anti-roll-up effect.

[0077] Optionally, if the anti-winding adsorption ring groove 21 is set to a circular shape, then the multiple anti-winding adsorption ring grooves 21 are distributed in the form of concentric circles.

[0078] Furthermore, the ring widths of the multiple anti-winding adsorption ring grooves 21 are not completely equal, and the ring width of the anti-winding adsorption ring groove 21 that is closer to the wafer 5 in the radial direction is greater than the ring width of the anti-winding adsorption ring groove 21 that is farther away from the wafer 5 in the radial direction.

[0079] Specifically, for multiple anti-winding adsorption ring grooves 21, they can adopt completely different ring widths. In the radially outward direction, the ring width of the anti-winding adsorption ring groove 21 decreases sequentially. Of course, for multiple anti-winding adsorption ring grooves 21, their ring widths can also be partially the same. For example, the innermost anti-winding adsorption ring groove 21 closest to the wafer 5 has the widest ring width, and the outermost anti-winding adsorption ring groove 21 furthest from the wafer 5 has the narrowest ring width. The ring widths of the other anti-winding adsorption ring grooves 21 located between the innermost and outermost ring grooves can be equal.

[0080] In this embodiment, as shown in the attached figure... Figure 1 As shown in the attached figure, there are two anti-winding adsorption ring grooves 21. The inner anti-winding adsorption ring groove 21 closer to the wafer 5 has a wider ring width, while the outer anti-winding adsorption ring groove 21 farther from the wafer 5 has a narrower ring width. Figure 4 As shown. The purpose of this design is that the outer anti-roll adsorption groove 21, due to its narrower ring width, can generate a greater adsorption force, quickly and forcefully adsorbing the edge of the coating; while the inner anti-roll adsorption groove 21, with its wider ring width, can form a larger adsorption area, further consolidating the adsorption stability of the coating near the inner part of the wafer 5. The combination of the two widths of the anti-roll adsorption groove 21 can effectively prevent the edge of the cut coating center portion from shrinking and curling, thus preventing the edge die from falling off during the casting process.

[0081] Optionally, the ratio of the minimum to the maximum ring width among the plurality of anti-winding adsorption ring grooves 21 ranges from 1:1.5 to 1:3, and the depth of the anti-winding adsorption ring groove 21 is greater than its ring width. Further optionally, the minimum ring width of the anti-winding adsorption ring groove 21 ranges from 0.4 mm to 0.8 mm, the maximum ring width ranges from 0.6 mm to 1.2 mm, and the depth of the anti-winding adsorption ring groove 21 ranges from 1 mm to 5 mm.

[0082] In this embodiment, the width of the inner anti-winding adsorption ring groove 21 ranges from 0.6 mm to 1.2 mm, and the width of the outer anti-winding adsorption ring groove 21 ranges from 0.4 mm to 0.8 mm. The two grooves have the same depth, which ranges from 1 mm to 5 mm.

[0083] Furthermore, the base 1 is also constructed with an outer main adsorption ring groove 22, which is located between the cutting ring groove 4 and the outermost anti-winding adsorption ring groove 21. Multiple anti-winding adsorption ring grooves 21 are evenly distributed radially in the area between the outer main adsorption ring groove 22 and the edge of the wafer 5.

[0084] Specifically, as shown in the attached diagram. Figure 1 As shown, the base 1 also has an outer main adsorption ring groove 22 located outside the outermost anti-curling adsorption ring groove 21. The outer main adsorption ring groove 22 is used to mainly adsorb and fix the coating. The outermost part of the outer main adsorption ring groove 22 is the cutting ring groove 4. There are no other adsorption structures between the outer main adsorption ring groove 22 and the cutting ring groove 4. Therefore, the curling of the coating after cutting mainly occurs in the area between the outer main adsorption ring groove 22 and the edge of the wafer 5. Therefore, to ensure the anti-curling effect, the multiple anti-curling adsorption ring grooves 21 are radially evenly distributed in the area between the outer main adsorption ring groove 22 and the edge of the wafer 5.

[0085] Furthermore, considering that the ring width of the anti-winding adsorption ring groove 21 may vary, the uniform distribution in this embodiment mainly refers to the uniformity of the approximate distribution position, and does not necessarily mean that the interval distance values ​​are exactly the same. It can also mean that the spacing is within the same value range. For example, in this embodiment, the distance between the inner anti-winding adsorption ring groove 21 and the outer anti-winding adsorption ring groove 21 is 5mm to 7mm, and the distance between the outer anti-winding adsorption ring groove 21 and the outer main adsorption ring groove 22 is 5mm to 7mm.

[0086] Furthermore, the ring widths of the multiple anti-winding adsorption ring grooves 21 are not completely equal, and the ring width of the outer main adsorption ring groove 22 is greater than the minimum ring width among the multiple anti-winding adsorption ring grooves 21 and less than the maximum ring width among the multiple anti-winding adsorption ring grooves 21.

[0087] Specifically, the ring width affects both the adsorption force and the adsorption area. For example, as mentioned above, the outer anti-roll adsorption ring groove 21, due to its narrower ring width, can generate a greater adsorption force, but its adsorption area is smaller; while the inner anti-roll adsorption ring groove 21, with its wider ring width, can generate a larger adsorption area, but its adsorption force is smaller. Therefore, for the outer main adsorption ring groove 22, which plays a major role in adsorbing the coating, it needs to balance adsorption area and adsorption force, so the ring width used is between the minimum and maximum ring width of the anti-roll adsorption ring groove 21.

[0088] Furthermore, the base 1 is also constructed with at least one inner main adsorption ring groove 23 and at least one radial adsorption groove 24. The inner main adsorption ring groove 23 corresponds to the wafer 5, and the radial adsorption groove 24 is connected in the radial direction to each inner main adsorption ring groove 23 and the outer main adsorption ring groove 22 in sequence.

[0089] Specifically, as shown in the attached diagram. Figure 1As shown, the outer main adsorption ring groove 22 cooperates with the inner main adsorption ring groove 23 through the radial adsorption groove 24 to jointly achieve the main adsorption effect on the coating. At the same time, the radial adsorption groove 24 is also connected to each anti-roll adsorption ring groove 21, so as to achieve the overall adsorption effect. The outer main adsorption ring groove 22, the inner main adsorption ring groove 23 and the radial adsorption groove 24 have the same width and depth. The width ranges from 0.5mm to 1mm and the depth ranges from 1mm to 5mm.

[0090] In addition, please refer to the attached figure. Figure 1 In this embodiment, the base 1 has a radius of approximately 195 mm and consists of one outer main adsorption ring groove 22 and two inner main adsorption ring grooves 23. The outer main adsorption ring groove 22 has a radius of 90 mm, the innermost inner main adsorption ring groove 23 has a radius of 40 mm, and the other inner main adsorption ring groove 23 has a radius of 70 mm. The cutting ring groove 4 is located 3 mm to 4 mm from the edge of the base 1, has a depth of 1 mm to 5 mm, and a width of 0.5 mm to 1 mm.

[0091] Furthermore, as shown in the attached figure Figure 1 As shown, an alignment mark 11 is provided on the surface of the base 1. The shape of the alignment mark 11 is the same as the shape of the positioning edge of the wafer 5. In this embodiment, the alignment mark 11 is set as a straight line with the same shape as the positioning straight edge of the wafer 5.

[0092] Furthermore, as shown in the attached figure Figure 2 and Figure 3 As shown, the base 1 also has a vacuum channel 3 inside. The vacuum channel 3 connects to the various adsorption ring grooves on the base 1. That is, one end of the vacuum channel 3 connects to the adsorption structure 2 on the base 1, which is composed of the anti-winding adsorption ring groove 21, the outer main adsorption ring groove 22, the inner main adsorption ring groove 23, and the radial adsorption groove 24. The other end of the vacuum channel 3 is connected to a vacuum pump 8 through a pipeline. The vacuum pump 8 creates a negative pressure in the groove of the adsorption structure 2, thereby generating an adsorption force. A control valve 31 is installed in the pipeline structure connecting the vacuum channel 3 and the vacuum pump 8.

[0093] Example 4

[0094] This utility model provides a wafer cutting system that includes the wafer cutting apparatus described in the above embodiments, thereby possessing all the technical effects described therein. The wafer cutting system may also include a vacuum device 8, a cutting device, etc.

[0095] Example 5

[0096] This utility model provides a wafer cutting system that includes the wafer cutting apparatus described in the above embodiments, thereby possessing all the technical effects described therein. The wafer cutting system may also include a vacuum device 8, a cutting device, etc.

[0097] (1) After the SiC wafer 5 completes the laser scribing or dicing process, it first undergoes film expansion. Before film expansion, ensure that the back film is properly attached, such as V8 blue film or ELPWS-02TH film. This invention is not limited to these two types of film. Then, film expansion is performed on the film expansion machine, with the top cylinder moving upward by 10-100um to ensure that each die is fully separated, as shown in the attached figure. Figure 6 As shown, the wafer, after expansion and slicing, is fixed onto the mother and daughter rings 6 by the blue film.

[0098] (2) Place the expanded wafer 5 on the base 1 of the cutting device and position it: the inner ring of the mother-daughter ring 6 is fitted onto the base 1 of the cutting device, and rotate the mother-daughter ring 6 so that the long side (i.e. the positioning side) of the wafer 5 is aligned with the alignment mark 11 on the base 1. Then press down the mother-daughter ring 6 to fix it, and turn on the vacuum equipment so that the wafer 5 and the back film are adsorbed onto the base 1 together.

[0099] (3) Cut the film and remove the mother and daughter rings 6. When cutting the film, cut along the cutting ring groove 4. After cutting the film, the blue film or other films on the back side will shrink back. However, because the anti-winding adsorption ring groove 21 adsorbs the film onto the base 1 of the cutting device, it can prevent the edge from rolling to the edge of the wafer 5, causing the edge die to fall off during the film casting process. Remove the mother and daughter rings 6 in time after cutting the film.

[0100] (4) Apply the front film. First, put on the iron ring 7 for positioning. When positioning, make sure that the two grooves of the iron ring 7 and the positioning pin 71 (the positioning pin 71 is used to cooperate with the grooves of the iron ring 7 to position the iron ring 7 and keep the iron ring 7 relatively fixed) are aligned. Then apply the film to the front, such as D-485H UV film or ELPWS-02TH film. This utility model is not limited to these two types of film.

[0101] (5) UV removal of the front film. This is mainly to facilitate the subsequent removal of the front film. The UV removal energy is 400-1000mj / cm2, and the UV removal time is 6-20s.

[0102] (6) Remove the blue film or other back film from step (1). Since the film has been cut and the mother and daughter rings 6 have been removed in step (3), the blue film or other back film is directly removed in this step, and then the back film is applied, such as D-485H UV film or ELPWS-02TH film. This utility model is not limited to these two types of film.

[0103] (7) Finally, peel off the front UV film, thus completing all the processes of cutting and pouring the film.

[0104] In the description of this utility model, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", 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 this utility model 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 utility model.

[0105] While specific embodiments of the present invention have been described herein with reference to them, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A wafer cutting device, characterized in that, include: A base for holding a wafer with a film coating on its surface, the base surface having a cutting annular groove for cooperating with a cutting tool; as well as An anti-winding adsorption ring groove is constructed on the surface of the base and located inside the cutting ring groove. The anti-winding adsorption ring groove is configured to adsorb the coating on the wafer surface by vacuuming. The anti-winding adsorption groove and the film cutting groove both surround the wafer placed on the base, and both correspond to the outer portion of the coating that extends beyond the edge of the wafer.

2. The wafer cutting apparatus according to claim 1, characterized in that, The number of anti-winding adsorption ring grooves is multiple, the centers of the multiple anti-winding adsorption ring grooves are concentric, and the diameters of the multiple anti-winding adsorption ring grooves are different.

3. The wafer cutting apparatus according to claim 2, characterized in that, The ring widths of the plurality of anti-winding adsorption ring grooves are not completely equal, and the ring width of the anti-winding adsorption ring grooves that are radially closer to the wafer is greater than the ring width of the anti-winding adsorption ring grooves that are radially farther away from the wafer.

4. The wafer cutting apparatus according to claim 3, characterized in that, The ratio of the minimum ring width to the maximum ring width in the plurality of anti-winding adsorption ring grooves ranges from 1:1.5 to 1:3, and the depth of the anti-winding adsorption ring groove is greater than its ring width.

5. The wafer cutting apparatus according to claim 2, characterized in that, The base is also constructed with a peripheral main adsorption ring groove, which is located between the film cutting ring groove and the outermost anti-winding adsorption ring groove. Multiple anti-winding adsorption ring grooves are evenly distributed radially in the area between the peripheral main adsorption ring groove and the wafer edge.

6. The wafer cutting apparatus according to claim 5, characterized in that, The ring widths of the plurality of anti-winding adsorption ring grooves are not completely equal. The ring width of the outer main adsorption ring groove is greater than the minimum ring width among the plurality of anti-winding adsorption ring grooves and less than the maximum ring width among the plurality of anti-winding adsorption ring grooves.

7. The wafer cutting apparatus according to claim 5, characterized in that, The base is also constructed with at least one inner main adsorption ring groove and at least one radial adsorption groove. The inner main adsorption ring groove corresponds to the wafer, and the radial adsorption groove is connected in the radial direction to each of the inner main adsorption ring grooves and the outer main adsorption ring grooves.

8. The wafer cutting apparatus according to claim 1, characterized in that, Alignment marks are provided on the surface of the base, and the shape of the alignment marks is the same as the shape of the positioning edge of the wafer.

9. The wafer cutting apparatus according to any one of claims 1 to 8, characterized in that, The base also has a vacuum channel inside, which connects to each adsorption ring groove on the base, and the vacuum channel is connected to a vacuum pumping device through a pipeline.

10. A wafer cutting system, characterized in that, Includes the wafer cutting apparatus as described in any one of claims 1 to 9.

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