Expansion retaining ring

Abstract

An expansion retaining ring is provided that balances the maintenance of the annular shape of the ring body with the flexibility of the annular lip. The expansion retaining ring comprises: a ring body (12); and an annular lip (14), which is formed of a material softer than the ring body (12), is detachably mounted on the outer peripheral surface (12A) of the ring body (12), and protrudes outward from the outer peripheral surface (12A) of the ring body (12).

Description

[Technical Field]

[0001] The present invention relates to an expansion retaining ring, and more particularly to an expansion retaining ring for holding a diced tape on which a semiconductor wafer is mounted in an expanded state. [Previous Technology]

[0002] Conventionally, a workpiece dicing apparatus is known that, when manufacturing a semiconductor wafer (hereinafter referred to as a wafer), for example, by means of laser irradiation or the like, dicing a semiconductor wafer (hereinafter referred to as a wafer) with pre-processed dicing lines inside it into individual wafers (also referred to as individual wafers). (For example, see Patent Document 1).

[0003] The wafer is attached to a dicing tape, the outer periphery of which is fixed to a frame. The workpiece dicing device divides the wafer into individual wafers by expanding the dicing tape with an expansion ring, and then holds the dicing tape in an expanded state by an expansion holding ring. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2021-176201 [Summary of the Invention]

[0005] [The problem the invention aims to solve]

[0006] For example, in the case of an expansion retaining ring in which the ring body and the annular lip are integrally constructed, it is difficult to maintain the circular shape of the ring body and the softness of the annular lip when expanding and cutting the band.

[0007] That is, in order to maintain the ring body in a circular shape, a high-rigidity material, such as a hard resin, must be used. However, because the annular lip also hardens, there is a problem of the cutting strip breaking during expansion. Therefore, as a countermeasure to prevent cutting strip breakage, the thickness of the annular lip can be reduced to decrease its rigidity. However, this results in a shorter service life for the annular lip. Therefore, as another countermeasure to prevent breakage, a soft resin with low rigidity can be used. However, this makes it impossible to maintain the circular shape of the ring body with a high-tension cutting strip, and the expansion retaining ring may detach from the frame.

[0008] This invention was developed in view of the following problem, with the aim of providing an expansion retaining ring that balances the maintenance of the annular shape of the ring body with the flexibility of the annular lip. [Means for solving the problem]

[0009] The expansion retaining ring of the present invention has the following configuration to achieve the purpose of the present invention: an expansion retaining ring is used to retain a strap whose outer periphery is fixed to a frame in an expanded state. The expansion retaining ring has a ring body and an annular lip. The annular lip is formed by a material that is softer than the ring body, can be detachably mounted on the outer periphery of the ring body, and protrudes outward from the outer periphery of the ring body.

[0010] In a preferred embodiment of the present invention, the outer diameter of the annular lip is larger than the inner diameter of the frame.

[0011] A preferred embodiment of the present invention is a cyclic metal system and a cyclic lip resin system.

[0012] In a preferred embodiment of the present invention, the ring body system has an annular concave portion formed along the outer periphery of the ring body, and the annular lip system has an annular body portion that is inserted into and disposed in the annular concave portion.

[0013] In a preferred embodiment of the present invention, the size of the annular body portion in the direction of the central axis of the annular lip is smaller than the size of the annular concave portion.

[0014] In a preferred embodiment of the present invention, a fluororesin coating layer is provided on the outer surface of the ring body.

[0015] In a preferred embodiment of the present invention, the annular lip is coated with a color different from that of the ring body.

[0016] In a preferred embodiment of the present invention, the annular lip is colored differently depending on the type of annular lip.

[0017] In a preferred embodiment of the present invention, a tapered surface inclined relative to the central axis of the ring body is formed on the inner circumferential surface of the ring body.

[0018] In a preferred embodiment of the present invention, the size of the ring body in the direction of its central axis is determined according to the required expansion rate of the belt. [Effects of the Invention]

[0019] According to the present invention, the maintenance of the annular shape of the ring body and the softness of the annular lip can be taken into account.

Implementation Method

[0021] [Form for implementing the invention]

[0022] Hereinafter, embodiments of the expansion retaining ring of the present invention will be described with reference to the accompanying drawings.

[0023] Figure 1 is an overall perspective view of the expansion retaining ring 10 in the embodiment, and Figure 2 is an assembled perspective view of the expansion retaining ring 10 shown in Figure 1. Furthermore, Figure 3 is a cross-sectional view of the expansion retaining ring 10 shown in Figure 1.

[0024] As shown in Figures 1 to 3, the expansion retaining ring 10 of the embodiment includes a ring body 12 and an annular lip 14. The ring body 12 is an example of the ring body of the present invention, and the annular lip 14 is an example of the annular lip of the present invention. First, an example of a band held in an expanded state by the expansion retaining ring 10 will be described.

[0025] Figure 4 is an explanatory diagram showing an example of wafer cell 2. Figure 4 is a perspective view of IVA-based wafer cell 2 and a cross-sectional view of IVB-based wafer cell 2. The wafer cell 2 has a dicing tape (equivalent to adhesive tape) 4 held in an expanded state by the aforementioned expansion holding ring 10.

[0026] As shown in Figure 4, the wafer unit 2 includes a wafer 1, a film-like adhesive 3, a dicing tape 4, and a frame 5. The wafer 1 is attached to a dicing tape 4 with an adhesive layer of approximately 100 μm thickness on its surface, separated by the film-like adhesive 3. The outer periphery of the dicing tape 4 is fixed to the rigid annular frame 5. Furthermore, the dicing tape 4 has a central region 4A that is circular in plan view for attaching the wafer 1, and an annular region 4B that is donut-shaped in plan view between the outer edge of the central region 4A (the outer edge of the wafer 1) and the inner edge of the frame 5. The wafer 1 is transported into the workpiece dicing apparatus 50 (see Figure 5) in the state of the wafer unit 2, and is diced into individual wafers 6 by the workpiece dicing apparatus 50.

[0027] Figure 5 is an explanatory diagram showing the general configuration of the workpiece dividing device 50. Hereinafter, the wafer dividing operation performed by the workpiece dividing device 50 will be briefly explained.

[0028] First, as shown in VA of FIG5, the frame 5 of the wafer unit 2 is fixed to the frame fixing part 52 of the workpiece dicing device 50. Next, the expansion ring 54 is raised, and the annular region 4B of the dicing strip 4 is pushed upward from the back side of the dicing strip 4 (the side opposite to the surface on which the wafer 1 is attached). The dicing strip 4 is expanded by the rising action of the expansion ring 54, and the wafer 1 is divided into individual wafers 6 (see VB of FIG5). In addition, a roller 56 is rotatably provided on the top of the expansion ring 54 that pushes the annular region 4B upward to reduce the friction between the roller and the annular region 4B.

[0029] Next, as shown in VB of FIG5, the expansion retaining ring 10 is raised, so that the annular lip 14 is fitted into the surface 5A of the frame 5 through the annular portion region 4B (see VC of FIG5). Through the raising action of the expansion retaining ring 10, the cutting strip 4 is held in an expanded state. Next, as shown in VC of FIG5, the expansion ring 54 is lowered. At this time, although the expansion of the cutting strip 4 caused by the expansion ring 54 is released, it is still held in an expanded state without loosening because the annular lip 14 of the expansion retaining ring 10 is fitted into the surface 5A of the frame 5.

[0030] Returning to Figures 1 to 3, the expansion retaining ring 10 of the embodiment will be further described. As previously mentioned, the expansion retaining ring 10 has a ring body 12 and an annular lip 14.

[0031] The annular lip 14 is formed of a material softer than the ring body 12. As will be described later, the annular lip 14 is detachably mounted on the outer peripheral surface 12A of the ring body 12 and protrudes outward from the outer peripheral surface 12A of the ring body 12. Furthermore, the outer diameter of the annular lip 14 is configured to be larger than the inner diameter of the opening 5B of the frame 5 (see Figure 3). With this configuration, when the annular lip 14 in this example needs to pass through the opening 5B of the frame 5 shown in Figure 5, it is pressed against the inner edge of the opening 5B and elastically deformed and narrowed in diameter. Then, when passing through the opening 5B, it elastically returns to its original shape and expands in diameter, fitting into the surface 5A of the frame 5 (see VC in Figure 5) through the annular region 4B.

[0032] One example of the ring body 12 is made of metal. Aluminum can be cited as an example of the metal material constituting the ring body 12, but it is not limited to aluminum. Any metal material with high rigidity that is not easily deformed when the cutting strip 4 expands (in the state of VB in FIG. 5) and when the expansion is held (in the state of VC in FIG. 5) is suitable. One example of the annular lip 14 is made of resin. Polypropylene can be cited as an example of the resin material constituting the annular lip 14, but it is not limited to polypropylene. Any resin material with flexibility that is easily elastically deformed when the cutting strip 4 expands (in the state of VB in FIG. 5) is suitable.

[0033] As shown in Figure 3, a fluororesin coating layer 16 is provided on the outer surface of the ring body 12. This fluororesin coating layer 16 reduces the friction between the upper surface 12B (the surface that pushes the annular region 4B upwards) of the ring body 12 and the annular region 4B (see Figure 5). As a result, as shown in VB of Figure 5, when the annular region 4B is pushed upwards by the expanding retaining ring 10, the annular region 4B easily slides against the upper surface 12B of the ring body 12, thus preventing damage to the cutting strip 4.

[0034] As shown in FIG3, the ring body 12 has an annular recess 18 formed along the outer peripheral surface 12A of the ring body 12. Moreover, the annular lip 14 has an annular body portion 20 that is inserted into the annular recess 18. That is, in this example, the annular lip 14 is detachably mounted on the ring body 12 by means of the configuration of inserting the annular body portion 20 into the annular recess 18.

[0035] The annular lip 14 has: the aforementioned annular body portion 20; and a lip portion 22, which is formed by protruding outward from the outer peripheral surface 20A of the annular body portion 20 and can be fitted into the surface 5A of the frame 5.

[0036] In Figure 3, when the direction in which the expansion retaining ring 10 is inserted into the frame 5 is set to the upward direction, the lip 22 is formed in a shape that expands in diameter from the connecting portion connected to the annular body portion 20 downwards at the front end. According to the expansion retaining ring 10 having such a lip 22, the expansion retaining ring 10 can move through the frame 5 in the insertion direction (upward direction), but cannot move through the frame 5 in the reverse direction (downward direction) after passing through the opening 5B.

[0037] The expansion retaining ring 10 according to the embodiment described above has the following advantages. That is, because the annular lip 14 is formed of a material softer than the ring body 12 and is configured to be detachably mounted on the outer peripheral surface 12A of the ring body 12, the maintenance of the annular shape of the ring body 12 and the softness of the annular lip 14 can be balanced during the expansion of the cutting strip 4 (state VB in FIG. 5). Furthermore, in VB of FIG. 5, it is shown that after the cutting strip 4 is expanded by the expansion ring 54, it is further expanded by the expansion retaining ring 10. That is, it shows the state where the tension of the cutting strip 4 is at its highest.

[0038] Furthermore, because the ring body 12 is made of metal, the circular shape of the ring body 12 is easily maintained. Therefore, even when applied to the cutting strip 4 under high tension, the expansion retaining ring 10 can be prevented from detaching from the frame 5. Also, because the annular lip 14 is made of resin, the annular lip 14 is easily deformable. Therefore, damage to the cutting strip 4 can be suppressed when the cutting strip 4 expands.

[0039] Furthermore, as shown in FIG3, in the embodiment of the expansion retaining ring 10, the dimension a of the annular body portion 20 of the annular lip 14 in the thickness direction of the expansion retaining ring 10 is smaller than the dimension b of the annular concave portion 18. By adopting this configuration, the amount of elastic deformation of the lip 22 can be suppressed to a smaller extent. In addition, the thickness direction of the expansion retaining ring 10 is in the same direction as the direction of the central axis C of the annular lip 14.

[0040] Specifically, as shown in the cross-sectional view of the expansion retaining ring 10 in FIG6, the annular lip 14, which is in elastic deformation, is relatively pressed against the inner edge of the frame 5 through the opening 5B of the frame 5. In this way, the annular lip 14 abuts against the outer peripheral end 18A of the annular concave portion 18 and gradually tilts in the direction (downward direction) indicated by arrow symbol A, with the outer peripheral edge 20B of the annular body portion 20 as the fulcrum. Then, the lip 22 gradually elastically deforms in the same direction indicated by arrow symbol A while following the above tilting, and elastically returns to its original shape after passing through the opening 5B and fits into the surface 5A of the frame 5.

[0041] Here, compared to the configuration of this example shown in Figures 3 and 6, for example, in the case of an expansion retaining ring where the size a of the annular body portion 20 is equal to the size b of the annular concave portion 18, the aforementioned tilting action of the annular body portion 20 (tilting in the direction indicated by arrow A of the annular body portion 20) will not occur. Therefore, the elastic deformation of the lip 22 through the opening 5B is equal to the elastic deformation of the lip 22 shown in Figure 6 plus the amount of tilting action of the annular body portion 20, resulting in a large load being applied to the lip 22. In this embodiment, because the expansion retaining ring 10 adopts a configuration where the size a of the annular body portion 20 is smaller than the size b of the annular concave portion 18, the elastic deformation of the lip 22 can be suppressed to a smaller extent, resulting in an extended service life of the annular lip 14. Furthermore, by adopting the above configuration, the load applied to the cutting strip 4 from the lip 22 can be reduced, thus suppressing breakage of the cutting strip 4.

[0042] Furthermore, the expanded retaining ring 10 of the embodiment adopts a configuration in which the annular lip 14 can be freely attached to and detached from the ring body 12. The expanded retaining ring 10 in the workpiece dividing device 50 (see Figure 5) is repeatedly used. Even if the lip 22 wears or undergoes plastic deformation due to repeated use and reaches its usage limit, the annular lip 14 can still be removed from the ring body 12 and exchanged with a new annular lip 14. Therefore, according to the expanded retaining ring 10 of the embodiment, since only the annular lip 14 needs to be exchanged, the cost of replacement can be reduced compared to an expanded retaining ring in which the ring body and the annular lip are integrated.

[0043] As described above, the annular lip 14 has a limited lifespan on the lip 22. In that case, for example, if the annular lip 14 can be managed on a per-manufacturing-batch basis, then if one of the annular lips 14 manufactured in that batch has reached its lifespan, it can be determined that all the annular lips 14 manufactured in that batch have reached their lifespan.

[0044] In this embodiment, the annular lip 14 of the expansion retaining ring 10 is colored differently from the ring body 12. For example, when the ring body 12 is black, the annular lip 14 is colored blue. Furthermore, the annular lip 14 is colored differently for each manufacturing batch. This allows the manufacturing batch of the annular lip 14 to be identified by observing the color applied to it. As a result, if an annular lip 14 exceeding its usage limit is found, the use of all other annular lips 14 (i.e., expansion retaining rings 10) manufactured in the same batch can be immediately stopped. This prevents the expansion retaining ring 10 from detaching from the frame 5. Furthermore, regarding the method of coloring the annular lip 14, a method of adding pigment to the resin material of the annular lip 14 can be cited.

[0045] Furthermore, as shown in FIG3, in the embodiment of the expansion retaining ring 10, a tapered surface 24 inclined relative to the central axis C of the ring body 12 is formed on the inner circumferential surface 12C of the ring body 12. In FIG3, when the insertion direction of the expansion retaining ring 10 into the frame 5 is set to the upward direction, the tapered surface 24 is inclined from the upper part to the lower part of the opening 13 of the ring body 12 (see FIG9) in the direction of expanding diameter. This tapered surface 24 is effectively utilized when conveying the expansion retaining ring 10, as described later. Hereinafter, an example of a conveying device for conveying the expansion retaining ring 10 will be described.

[0046] Figure 7 is an overall perspective view of the conveying device 70 for conveying the expansion retaining ring 10, and Figure 8 is an enlarged view of the main parts of the conveying device 70 shown in Figure 7. As shown in Figures 7 and 8, the conveying device 70 includes a conveying arm 72 and three chucking mechanism parts 74.

[0047] As shown in FIG. 7, each clamping mechanism 74 has a bracket 76 connected to the conveying arm 72, and each bracket 76 extends radially with the holding fulcrum P of the conveying arm 72 as the center. As shown in FIG. 8, a cylinder 80 is installed on the front end side of each bracket 76, and a gripper 78 is installed on the front end of the piston 82 of each cylinder 80.

[0048] Each gripper 78 is arranged at equal intervals (120-degree intervals) on a concentric circle centered on the holding fulcrum P shown in FIG. 7, and reciprocates along the radial direction of the aforementioned concentric circle by the extension and retraction of the piston 82 shown in FIG. 8. By the extension of the piston 82, each gripper 78 moves from the position shown in FIG. 8 (retracted position) to the outer side in the radial direction, and when it is in the position shown in FIG. 9 (holding position), each gripper 78 is pushed against the tapered surface 24 of the expansion holding ring 10. By this action, the expansion holding ring 10 is held (clamped) in each clamping mechanism portion 74. Then, the expansion holding ring 10 is transported by the transport action of the transport arm 72, for example, to a position above the expansion ring 54 shown in FIG. 10.

[0049] Figure 10 is a magnified view showing the main part of the positional relationship between the conveyed expansion retaining ring 10 and the expansion ring 54. As shown in Figure 10, when the expansion retaining ring 10 is conveyed to the position above the expansion ring 54, each gripper 78 located in the holding position shown in Figure 9 moves to the radially inward side and to the retracted position shown in Figure 8 due to the contraction action of the piston 82. By this action, the holding (clamping) of the expansion retaining ring 10 caused by each clamping mechanism 74 is released, causing the expansion retaining ring 10 to fall toward the expansion ring 54.

[0050] As shown in FIG. 10, the expansion ring 54 is equipped with: a roller ring 90 having a plurality of rollers 56; and a roller ring receiving portion 92 having an outer diameter larger than that of the roller ring 90. The aforementioned falling expansion retaining ring 10 is seated on the upper surface 92A of the roller ring receiving portion 92. The roller ring receiving portion 92 is provided with a seating sensor (e.g., three locations, not shown) to detect whether the expansion retaining ring 10 is correctly seated on the upper surface 92A. Furthermore, in the case of a workpiece dividing device equipped with an expansion ring 54 having a roller ring receiving portion 92, as the expansion ring 54 rises, the expansion retaining ring 10 is also raised, and together with the expansion ring 54, expands the cutting strip 4.

[0051] Furthermore, in the conveying device 70 shown in Figures 7 to 9, there is a detection mechanism to check whether the expansion retaining ring 10 is held in the correct posture by each clamping mechanism 74. The correct posture refers to the posture used to correctly set the expansion ring 54 shown in Figure 10. Here, the posture shown in Figures 8 and 9 (the posture with the lip 22 drooping downwards) is the correct posture. In contrast to this correct posture, the incorrect posture shown in Figure 11 (the posture with the lip 22 extended upwards) cannot correctly set the expansion retaining ring 10 on the expansion ring 54. Therefore, it is necessary to detect the expansion retaining ring 10 when it is held in an incorrect posture and stop the conveying of the expansion retaining ring 10. Hereinafter, the conveying device 70 uses the tapered surface 24 of the expansion retaining ring 10 to detect the aforementioned incorrect posture. Hereinafter, an example of a detection device used to detect the incorrect posture will be briefly explained.

[0052] As the detection device in this example, an adsorption pressure sensor (not shown) and a cylinder sensor (not shown) are used to detect incorrect posture. Specifically, as shown in FIG12, the clamping mechanism 74 has a suction nozzle (vaccum pad) 84 that operates integrally with the gripper 78 (see FIG8) via a piston 82. The suction nozzle 84 is positioned to adsorb onto the tapered surface 24 when the gripper 78 is pushed against and contacts the tapered surface 24. When the suction nozzle 84 adsorbs onto the tapered surface 24, a negative pressure is generated between the suction nozzle 84 and the tapered surface 24, and this negative pressure is detected by the aforementioned adsorption pressure sensor.

[0053] Furthermore, the clamping mechanism 74 has the aforementioned cylinder sensor that detects the elongation of the piston 82. In this example, the cylinder sensor sets the elongation of the piston 82 when the clamp 78 is in the correct posture (see Figure 9) and presses against the tapered surface 24 within the sensor range, and sets the elongation of the piston 82 when the clamp 78 is in an incorrect posture (see Figure 11) and presses against the tapered surface 24 outside the sensor range.

[0054] Specifically, as shown in FIG9, when held in the correct position, the tapered surface 24 of the expansion retaining ring 10 is inclined in the direction of expanding diameter from the top to the bottom of the opening 13 of the ring body 12. Moreover, in the correct position of FIG9, the gripper 78 is pressed against the upper part of the tapered surface 24 (the small diameter part of the opening 13). On the other hand, as shown in FIG11, in the incorrect position where the top and bottom are reversed, the gripper 78 is pressed against the large diameter part located below the small diameter part of FIG9. That is to say, the elongation of the piston 82 is greater when held in the incorrect position where the top and bottom are reversed compared to the elongation when held in the correct position. By utilizing the tapered surface 24 to make the extension of piston 82 different, as described above, the extension of piston 82 when held in the correct posture (see Figure 9) can be set within the sensor range, and the extension of piston 82 when held in the incorrect posture (see Figure 11) can be set outside the sensor range.

[0055] According to the detection device in this example, when the gripper 78 is pressed against the tapered surface 24 in the correct posture (see Figure 9), a negative pressure is detected by the suction pressure sensor, and the elongation of the piston 82 is detected by the cylinder sensor. That is, because the sensors of both sides are ON, it is determined that the expansion retaining ring 10 is held in the correct posture, allowing the expansion retaining ring 10 to be transported.

[0056] On the other hand, when the gripper 78 is pressed against the tapered surface 24 in an incorrect upside-down posture (see FIG11), the extension of the piston 82 is greater compared to when the gripper 78 is pressed against the tapered surface 24 in the correct posture (see FIG9). In this case, although a negative pressure is detected by the suction pressure sensor, the cylinder sensor does not react because it is outside the sensing range. That is, because neither sensor is ON, it is determined that the expansion retaining ring 10 is held in an incorrect posture, and the transport of the expansion retaining ring 10 is not allowed. In this case, it is preferable, for example, to display an error pop-up window on the operation screen of the workpiece dividing device 50 and issue a warning.

[0057] Returning to Figure 3, further explanation is given regarding the expansion retaining ring 10. As for the expansion retaining ring 10, the dimension d (d1) of the ring body 12 in the thickness direction (direction of the central axis C of the annular lip 14) of the expansion retaining ring 10 is determined according to the required expansion rate of the cutting strip 4.

[0058] Here, the expansion retaining ring 100 of another embodiment shown with reference to FIG13 will be described. In addition, when describing the expansion retaining ring 100, the same reference numerals will be used for the same or similar components as those of the expansion retaining ring 10 shown in FIG3.

[0059] In cases where a high expansion rate of the cutting strip 4 is required, as shown in FIG13, the expansion retaining ring 100 uses a ring body 102 with a dimension d changed from d1 (see FIG3) to d2 (d1 < d2). Specifically, the ring body 102 uses a dimension e between the mounting surface 18B, where the annular lip 14 is mounted, and the upper surface 12B in the inner surface of the annular recess 18, which is changed from e1 (see FIG3) to e2 (e1 < e2). Then, the annular lip 14 is installed in the annular recess 18 of the ring body 102 without change.

[0060] The expansion retaining ring 100 shown in FIG13 is suitable for cutting strips 4 that require a high expansion rate because it has a ring body 102 with the above-mentioned dimensions (d2, e2). In addition, in the case of cutting strips 4 that require a low expansion rate, the above-mentioned dimensions (d, e) can be reduced according to the required expansion rate.

[0061] As described above, since the expansion retaining rings 10 and 100 in each of the above embodiments are configured to be detachably mounted on the ring bodies 12 and 102, the ring bodies 12 are selected to correspond to the required expansion rate, but the annular lips 14 can be used interchangeably. That is, for each embodiment of the expansion retaining rings 10 and 100, as long as the manufacturing molds for the ring bodies 12 and 102 corresponding to the required expansion rate are prepared in advance, one type of manufacturing mold for the annular lips 14 can be used.

[0062] Furthermore, in the above embodiments, the expansion holding rings 10 and 100 for holding the dicing strip 4 in an expanded state have been described. However, the expansion holding rings 10 and 100 can also be used to expand the dicing strip 4 and divide the wafer 1 into individual wafers. That is, the expansion holding rings 10 and 100 can also be equipped with the function of expansion rings 54. In this case, by moving the expansion holding rings 10 and 100 up and down relative to the wafer cell 2, the annular portion 4B of the dicing strip 4 is pushed upward by the ring body 12 and 102 of the expansion holding rings 10 and 100. In this way, the wafer 1 can be divided into individual wafers 6 by the expansion holding rings 10 and 100. Then, the dicing strip 4 is held in an expanded state by the expansion holding rings 10 and 100.

[0063] The above describes one example of the expansion retaining ring of the present invention, but the technology of the present invention is not limited to the embodiment and several improvements or modifications can be made without departing from the spirit of the present invention. [Simplified Explanation of the Diagram]

[0020] Figure 1 is an overall perspective view of the expanded retaining ring in an embodiment. Figure 2 is an assembled perspective view of the expanded retaining ring shown in Figure 1. Figure 3 is a cross-sectional view of the expanded retaining ring shown in Figure 1. Figure 4 is an explanatory diagram of a wafer cell with a dicing strip. Figure 5 is an explanatory diagram showing the general structure of a workpiece dicing device. Figure 6 is a cross-sectional view showing the state of the lip body tilting relative to the ring body. Figure 7 is an overall perspective view of a conveying device for conveying the expanded retaining ring. Figure 8 is an enlarged view of the main parts of the conveying device shown in Figure 7. Figure 9 is an enlarged view of the main parts of the expanded retaining ring held by the conveying device. Figure 10 is an enlarged view of the main parts showing the positional relationship between the conveyed expanded retaining ring and the expanded ring. Figure 11 is an enlarged view of the main parts when the expanded retaining ring is held in an incorrect posture. Figure 12 is an explanatory diagram showing the suction nozzle (vaccum pad) adsorbed onto the tapered surface. Figure 13 is a cross-sectional view showing other forms of the expanded retaining ring.

Claims

1. An expansion retaining ring for retaining a strap whose outer periphery is fixed to a frame in an expanded state. The expansion retaining ring has a ring body and an annular lip. The annular lip is formed of a material softer than the ring body, is detachably mounted on the outer periphery of the ring body, and protrudes outward from the outer periphery of the ring body. The ring body has an annular recess formed along the outer periphery of the ring body. The annular lip has an annular body portion that is inserted into the annular recess. The size of the annular body portion in the central axis direction of the annular lip is smaller than the size of the annular recess.

2. The expansion retaining ring as claimed in claim 1, wherein the aforementioned annular lip is fitted with a color different from that of the aforementioned ring body.

3. The expansion retaining ring as claimed in claim 2, wherein the aforementioned annular lip is colored differently depending on the type of the aforementioned annular lip.

4. An expansion retaining ring as claimed in any of claims 1 to 3, wherein a tapered surface inclined relative to the central axis of the aforementioned ring body is formed on the inner circumferential surface of the aforementioned ring body.

5. An expansion retaining ring for retaining a strap whose outer periphery is fixed to a frame in an expanded state. The expansion retaining ring has a ring body and an annular lip. The annular lip is formed of a material softer than the ring body, is detachably mounted on the outer periphery of the ring body, and protrudes outward from the outer periphery of the ring body. The annular lip is colored differently from the ring body, and the different colors are applied to the annular lip depending on the type of annular lip.

6. The expansion retaining ring of claim 5, wherein a tapered surface inclined relative to the central axis of the aforementioned ring body is formed on the inner circumferential surface of the aforementioned ring body.

7. An expansion retaining ring for retaining a strap whose outer periphery is fixed to a frame in an expanded state. The expansion retaining ring has a ring body and an annular lip. The annular lip is formed of a material softer than the ring body, is detachably mounted on the outer periphery of the ring body, and protrudes outward from the outer periphery of the ring body. A tapered surface inclined relative to the central axis of the ring body is formed on the inner periphery of the ring body.

8. The expansion retaining ring as claimed in claim 7, wherein the aforementioned annular lip is fitted with a color different from that of the aforementioned ring body.

9. An expansion retaining ring as claimed in any of claims 5 to 8, wherein the ring body has an annular recess formed along the outer periphery of the ring body, and the annular lip has an annular body portion inserted into the annular recess.

10. An expansion retaining ring as claimed in any of claims 1 to 3, 5 to 8, wherein the outer diameter of the aforementioned annular lip is greater than the inner diameter of the aforementioned frame.

11. An expansion retaining ring as claimed in any of claims 1 to 3, 5 to 8, wherein the aforementioned ring is made of metal and the aforementioned annular lip is made of resin.

Images