Method and apparatus for cutting adhesive tape

Abstract

This makes it less likely for fibrous residue to be produced when cutting adhesive tape used for dicing. [Solution] A cutting line CL of the adhesive tape 62 is set along the surface of the ring frame 20. This cutting method includes a cutting step of placing the rotating blade 40 on the cutting line CL at a cutting position Cp offset by a predetermined distance from a cutting position C0 to which the rotating blade 40 is placed; a moving step of relatively moving the rotating blade 40 and the ring frame 20 so that the rotating blade 40 is directed from the cutting position Cp towards the cutting line CL; and a cutting step of rotating the rotating blade 40 in a circle along the cutting line CL from a starting point C0 on the cutting line CL.

Description

Technical Field

[0001] The present invention relates to a method for cutting an adhesive tape for attaching a wafer to a ring frame.

Background Art

[0002] In the pre-process of semiconductor manufacturing, a wafer on which a large number of devices are formed is divided into a plurality of chips for each device in the dicing process. Prior to the dicing process, probing is performed to remove defective products from the devices on the wafer, and then back grinding is performed to sufficiently thin the thickness of the wafer.

[0003] In the back grinding process, after attaching a protective tape so as to cover the surface of a wafer on which a plurality of devices are formed, the wafer is turned over and the back surface is polished. Then, an adhesive tape is attached from the back surface side of the wafer to integrate the wafer and the ring frame. After the adhesive tape is attached to the ring frame, it is cut into a circular shape by circulating a rotary blade on the ring frame (see Patent Document 1). Then, the wafer is conveyed together with the ring frame toward the chuck table of the dicing apparatus.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, when the adhesive tape is cut into a circular shape with a rotary blade as described above, the start point and the end point of the cutting may be displaced, and residues like whiskers may occur on the outer peripheral portion of the adhesive tape. If this residue overlaps on the surface of the adhesive tape, it may cause problems later, such as causing the wafer to tilt when the ring frame is installed in the dicing process.

[0006] This invention has been made in view of these circumstances, and one of its objectives is to make it difficult to generate whisker-like residue when cutting adhesive tape for dicing. [Means for solving the problem]

[0007] One aspect of the present invention is a cutting method for cutting an adhesive tape, which is attached to cover the surface of a ring frame placed on the outside of a wafer, along the surface of the ring frame using a rotary blade. In this cutting method, a cutting line of the adhesive tape is set along the surface of the ring frame. This cutting method comprises a blade-setting step of setting the rotary blade at a blade-setting position offset by a predetermined distance from the position where the rotary blade is set to touch the cutting line; a movement step of relatively moving the rotary blade and the ring frame so that the rotary blade is directed from the blade-setting position toward the cutting line; and a cutting step of rotating the rotary blade around the cutting line from a starting point on the cutting line.

[0008] Another aspect of the present invention is an adhesive tape cutting apparatus. This cutting apparatus comprises a table on which a wafer and a ring frame are placed such that the ring frame is positioned outside the wafer, a tape supply mechanism for applying adhesive tape to cover the surfaces of the wafer and the ring frame, a rotatably supported rotating blade, a moving mechanism provided to allow relative movement between the rotating blade and the table, and a control unit for controlling the rotating blade and the table. A cutting line of the adhesive tape is set along the surface of the ring frame. The control unit places the rotating blade at a position offset by a predetermined distance from the position where the rotating blade is placed on the cutting line, moves the rotating blade and the ring frame relative to each other so that the rotating blade is directed from the placement position towards the cutting line, and causes the rotating blade to revolve along the cutting line from the starting point on the cutting line. [Effects of the Invention]

[0009] According to the present invention, it is possible to make it difficult to generate whisker-like residue when cutting adhesive tape. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view showing the schematic configuration of the cutting device according to the embodiment. [Figure 2] This diagram schematically represents the configuration of the tape supply mechanism. [Figure 3] This diagram schematically represents the structure of the tape retrieval mechanism. [Figure 4] This is a plan view showing the configuration of the chuck unit. [Figure 5] This is a side view showing the configuration of the cutter unit. [Figure 6] This is a partially enlarged cross-sectional view showing the configuration of the rotating mechanism. [Figure 7] This is a view taken in the direction of arrow B in Figure 6. [Figure 8] This diagram illustrates the cutting process for adhesive tape. [Figure 9] This diagram illustrates the cutting process for adhesive tape. [Figure 10] This is a schematic cross-sectional view illustrating the operation of the cutter and roller. [Figure 11] This diagram schematically illustrates the phenomena that can occur during the cutting process. [Figure 12] This diagram schematically illustrates a method for cutting adhesive tape according to an embodiment. [Figure 13] This is a flowchart illustrating the process of cutting adhesive tape. [Figure 14] This diagram illustrates a modified method for cutting adhesive tape. [Figure 15] This diagram illustrates a method for cutting adhesive tape related to other variations. [Modes for carrying out the invention]

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following embodiment and its modified examples, substantially identical components are denoted by the same reference numerals, and their descriptions are omitted as appropriate.

[0012] In the adhesive tape cutting device of this embodiment (hereinafter simply referred to as "cutting device"), a circular cutting line is set along the surface of the ring frame to which the adhesive tape is attached. When the rotary blade is set to the cutting edge, the cutting edge position is offset by a predetermined distance from the initial position set on the cutting line. In other words, it is deliberately shifted from the cutting line, and after the rotary blade advances a predetermined distance by cutting the adhesive tape, it reaches the starting point on the cutting line and orbits along the cutting line. By setting this predetermined distance, it is possible to prevent the occurrence of beard-like residues on the outer periphery of the adhesive tape. The details will be described below.

[0013] (Overall configuration of the cutting device) FIG. 1 is a perspective view showing a schematic configuration of the cutting device according to the embodiment. Hereinafter, for convenience of explanation, the left - right direction, front - rear direction, and up - down direction when viewing the cutting device from the front will be described as the X direction, Y direction, and Z direction, respectively.

[0014] The cutting device 1 includes a table 10, a table moving mechanism 12, a tape attaching unit 14, and a cutter unit 16. The table 10 has a chuck unit 18 for supporting the wafer W. The ring frame 20 is attached to the table 10. Also, the wafer W that has undergone the back grinding process is transported to and attached to the table 10 by a transport mechanism (not shown).

[0015] The ring frame 20 is attached to the chuck unit 18. The wafer W is held by the chuck unit 18 so as to be disposed inside the ring frame 20. For example, the wafer W is held by the chuck unit 18 concentrically with the ring frame 20. The table moving mechanism 12 has a pair of guide rails 22 and a drive unit 24 for moving the table 10 in the X direction, and moves the table 10 in the X direction when attaching, cutting, and peeling the adhesive tape to / from the wafer W (details will be described later).

[0016] The tape application unit 14 includes a tape supply mechanism 26 and a tape retrieval mechanism 28. The tape supply mechanism 26 includes a supply section 30 to which a roll of raw material around which adhesive tape is wound is attached, a press roller 32 that biases in the direction of attaching the adhesive tape, a winding section 34 that winds up the separator peeled off from the adhesive tape, and a plurality of rollers arranged between these.

[0017] On the other hand, the tape recovery mechanism 28 has a recovery unit 36 ​​that winds up the remaining (cut) portion of the adhesive tape after it has been attached to the wafer W and cut, and a plurality of rollers that feed the adhesive tape toward the recovery unit 36.

[0018] The cutter unit 16 includes a cutter 40 for cutting adhesive tape, a lifting mechanism 42 for raising and lowering the cutter 40 relative to the ring frame 20, and a rotating mechanism 44 for moving the cutter 40 along the ring frame 20 during cutting (details will be described later).

[0019] A control unit 50 is provided inside the housing of the cutting device 1. The control unit 50 consists of a general-purpose computer and includes a CPU for executing various calculation processes, memory or storage for storing control programs, memory used as a work area for data storage and program execution, input / output interfaces, etc. The control unit 50 controls each functional part (mechanism and device) of the cutting device 1 according to the control program.

[0020] The wafer W, which is integrated with the ring frame 20, is moved to a retracted position along with the table 10 by the drive unit 24 after the adhesive tape is cut in a circular shape by the cutting device 1. Then it is transported to the dicing device by a transport mechanism (not shown).

[0021] (Configuration of the tape supply mechanism) Figure 2 is a schematic diagram showing the configuration of the tape supply mechanism 26. Guide rollers 52, feed roller 54, and guide roller 56 are provided between the supply unit 30 and the press roller 32. The supply unit 30 has a support shaft 60 that rotatably supports the raw material roll 58. The raw material roll 58 is made by winding a tape raw material 66 in which a separator 64 (release sheet) is attached to the adhesive layer of an adhesive tape 62. The feed roller 54 includes a drive roller 54a and a driven roller 54b.

[0022] Meanwhile, a feed roller 68 and a guide roller 70 are provided between the press roller 32 and the winding section 34. The feed roller 68 includes a drive roller 68a and a driven roller 68b. Near the press roller 32, a peel plate 72 is positioned to separate the tape roll 66 into adhesive tape 62 and separator 64. The separator 64 is peeled off by the peel plate 72, allowing the adhesive tape 62 to perform its adhesive function. The winding section 34 has a support shaft 76 that rotatably supports a roll 74 around which the peeled separator 64 is wound.

[0023] When supplying the adhesive tape 62, the tape roll 66 unwound from the supply unit 30 is guided to the vicinity of the adhesion area PA via the guide roller 52, feed roller 54, and guide roller 56. Then, the tape roll 66 is separated into the adhesive tape 62 and separator 64 by the peel plate 72, and the adhesive tape 62 is supplied to the adhesion area PA. The separator 64 is guided to the winding unit 34 via the feed roller 68 and guide roller 70, and wound onto the roll 74.

[0024] The adhesive area PA is located between the tape supply mechanism 26 and the tape retrieval mechanism 28, and below the cutter unit 16 (see Figure 1). When the adhesive tape 62 is attached to the wafer W, the table 10 on which the wafer W and ring frame 20 are placed is positioned in the adhesive area PA. A cylinder (not shown) is driven to press the press roller 32 against the upper surface of the adhesive tape 62 (the side opposite to the adhesive layer), and by driving it in the left-right direction (X direction), the adhesive tape 62 is attached so as to cover the surfaces of the wafer W and ring frame 20.

[0025] Subsequently, the press roller 32 is retracted from the adhesion area PA, and the adhesive tape 62 along the ring frame 20 is cut. Prior to the dicing process, the adhesive tape 62 is cut to a shape that is necessary and sufficient to integrate the wafer W and the ring frame 20. Details of this adhesive tape 62 cutting process will be described later.

[0026] (Configuration of the tape retrieval mechanism) Figure 3 is a schematic diagram showing the configuration of the tape retrieval mechanism 28. Guide rollers 80, feed roller 82, and guide roller 84 are provided between the adhesive area PA and the recovery section 36. The feed roller 82 includes a drive roller 82a and a driven roller 82b. The recovery section 36 includes a support shaft 86 and a press roller 88. The support shaft 86 rotatably supports the roll 90 around which the adhesive tape 62 (cut portion) fed from the adhesive area PA is wound. The press roller 88 rotates while contacting the outer circumferential surface of the roll 90, preventing the outer diameter of the roll 90 from expanding too much.

[0027] When the adhesive tape 62 is wound up, the adhesive tape 62 fed out from the adhesive area PA is guided to the recovery section 36 via the guide roller 80, the feed roller 82, and the guide roller 84, and is wound onto the roll 90.

[0028] (Chuck unit configuration) Figure 4 is a plan view showing the configuration of the chuck unit 18. The chuck unit 18 includes a frame table 92 that supports the ring frame 20 and a chuck table 94 that supports the wafer W. The upper surface of the frame table 92 is provided with a complementary shape to the ring frame 20, for example, an annular groove 92a, into which the ring frame 20 is mounted and fixed.

[0029] A chuck table 94 is positioned inside the frame table 92. The chuck table 94 has a holding plate 96. The holding plate 96 is, for example, a disc-shaped porous material made of ceramics or the like, and its upper surface is an adsorption surface 98 for suction and holding the wafer W. The chuck table 94 is provided with a suction passage for evacuating the wafer W attached to the holding plate 96. The suction passage is connected to a vacuum source via piping (not shown).

[0030] The control unit 50 drives the vacuum source to create a vacuum, and the resulting suction force is applied to the wafer W through the porous structure of the suction surface 98. The wafer W is then attracted to the holding plate 96 by the negative pressure generated. The wafer W and the ring frame 20 are arranged coaxially (concentrically) around the axis L of the holding plate 96. In other words, in this embodiment, the axes of the wafer W, the ring frame 20, and the holding plate 96 (table 10) coincide.

[0031] (Cutter unit configuration) Figure 5 is a side view showing the configuration of the cutter unit 16. The cutter unit 16 comprises a base 100 (see Figure 1) erected on the rear side of the cutting device 1, a frame 102 that supports the cutter 40, and a lifting mechanism 42 that moves the frame 102 up and down along the base 100. The lifting mechanism 42 includes a linear guide 104 and a screw feed mechanism 106 provided on the base 100. The screw feed mechanism 106 is driven by a servo motor 108. The linear guide 104 extends vertically along the front surface of the base 100 and guides the frame 102 in the vertical direction (Z direction).

[0032] The frame 102 is cantilevered and extends forward from the base 100, and is located above the adhesive area PA. The frame 102 is provided with a rotation mechanism 44 that rotates (moves) the cutter 40 around a vertical axis L1. The rotation mechanism 44 includes a rotating shaft 110 along the axis L1, a motor 112 which is the drive unit, and a belt 114 that transmits the rotational driving force of the motor 112 to the rotating shaft 110.

[0033] A rotating arm 116 is attached to the tip of the rotating shaft 110. The rotating arm 116 is a long member extending horizontally, and its central part is connected to the rotating shaft 110. A cutter 40 (rotating blade) is attached to one end of the rotating arm 116, and a roller 43 (pressing roller) is attached to the other end. That is, the cutter 40 and the roller 43 are positioned symmetrically with respect to the axis L1 of the rotating shaft 110. The cutter 40 is a "rotating blade" that rotates around the horizontal axis L2. The roller 43 also rotates around the horizontal axis L3. The rotating arm 116 rotates when driven by the motor 112, and the cutter 40 and roller 43 each rotate and pivot around axis L1. In a modified example, a spindle motor may be directly connected to the rotating shaft 110. Furthermore, the cutter unit 16 may have a configuration other than those shown in the embodiments and modified examples. As long as the cutter 40 can cut the adhesive tape 62 along a predetermined cutting line, it may be configured to cut the adhesive tape 62 by rotating the cutter 40 as in the embodiments and modified examples, or it may be configured to cut the adhesive tape 62 along a cutting line by controlling the cutter 40.

[0034] Figure 6 is a partially enlarged cross-sectional view showing the configuration of the rotating mechanism 44. Figure 7 is a view in the direction of arrow B in Figure 6, showing the structure of the cutter 40 and its surroundings. As shown in Figure 6, the rotating mechanism 44 has a rotating unit 120 including a rotating shaft 110. The rotating unit 120 has a stepped cylindrical housing 122, which is fixed to the frame 102. The housing 122 rotatably supports the rotating shaft 110 via a pair of upper and lower bearings 124. The central axes of the bearings 124 coincide with the axis L1. An oil seal 126 is provided at the lower end of the housing 122. The oil seal 126 prevents the lubricating oil applied to the bearings 124 from leaking.

[0035] A pulley 128 is provided at the upper end of the rotating shaft 110, and a belt 114 is connected to it. The rotating shaft 110 has a through hole 129 along its axis L1, and couplings 130 and 132 are attached to its upper and lower ends. The through hole 129 forms an air passage through which air flows to finely adjust the height of the cutter 40. A tube connected to an air supply source (not shown) is connected to the coupling 130.

[0036] A cylinder mechanism 134 for fine-tuning the height of the cutter 40 is provided at one end of the rotating arm 116. The cylinder mechanism 134 includes a cylinder 135 (air cylinder) for drawing in and expelling air, a movable member 136 driven vertically by the operation of the cylinder 135, and a return spring (not shown) that biases the movable member 136 upward. A tube 138 connected to the cylinder 135 is connected to a joint 132. Air that has passed through the air passage of the rotating unit 120 is supplied to the cylinder 135 via the tube 138. In the standby state before transitioning to the cutting process, the cutter 40 is positioned higher than the lower surface of the roller 43. When transitioning to the cutting process, the cutter unit 16 descends and the roller 43 comes into contact with the adhesive tape 62, after which the cylinder 135 operates to lower the cutter 40 and press it against the adhesive tape 62. At this time, the height of the cutter 40 can be fine-tuned by controlling the cylinder 135.

[0037] A support member 140 is fixed to a movable member 136, and the cutter 40 is rotatably supported by the support member 140. The support member 140 is a plate-shaped member that extends in the vertical direction, and its upper part is fixed to the movable member 136. A pair of bearings 142 are provided at the lower part of the support member 140, and they rotatably support the rotation axis 40a of the cutter 40. The central axis of the bearings 142 coincides with the axis L2.

[0038] As shown in Figure 7, the support member 140 is fixed to the movable member 136 by a number of screws 150 (bolts), but the tilt of the cutter 40 can be finely adjusted prior to tightening the screws 150. Specifically, screw holes 152 are provided at the top, bottom, left, and right positions of the support member 140, and grub screws 154 are screwed into each of them.

[0039] By adjusting the amount of protrusion of these grub screws 154 on the surface of the support member 140 facing the movable member 136, the inclination of the support member 140, and consequently the inclination of the cutter 40 (rotating blade), can be adjusted. Specifically, by adjusting the amount of screwing in (protrusion) of the upper and lower grub screws 154, the inclination of the cutting surface of the cutter 40 relative to the vertical plane can be adjusted. In addition, by adjusting the amount of screwing in (protrusion) of the left and right grub screws 154, the inclination of the cutter 40 relative to the direction of travel can be adjusted.

[0040] Returning to Figure 6, a support member 144 is fixed to the other end of the rotating arm 116, and the roller 43 is rotatably supported by the support member 144. The support member 144 is a plate-shaped member that extends in the vertical direction, and its upper part is fixed to the rotating arm 116. A pair of bearings 146 are provided on a rotating shaft 145 located at the lower part of the support member 144, and the roller 43 is rotatably supported. The central axis of the bearings 146 coincides with the axis L3.

[0041] (How to cut adhesive tape) Next, we will explain how to cut the adhesive tape 62. As described above, after attaching the adhesive tape 62 to cover the wafer W and the ring frame 20, the adhesive tape 62 is cut in a circular shape along the ring frame 20.

[0042] Figures 8 and 9 illustrate the cutting process of the adhesive tape. Figure 10 is a schematic cross-sectional view showing the operation of the cutter 40 and roller 43, and corresponds to cross-section AA in Figure 4. As shown in Figure 8, a cutting line CL of the adhesive tape 62 is pre-set along the surface of the ring frame 20 with the wafer W positioned inside. In the cutting process, as shown in Figure 9, the cutter 40 and roller 43 are lowered. Then, by driving the rotation mechanism 44 to rotate (move) the roller 43 and cutter 40 along the cutting line CL, the adhesive tape 62 can be cut.

[0043] The cutting line CL is determined by the positional relationship between the ring frame 20 and the cutter 40, as well as the mechanical configuration of the ring frame 20 and the cutter 40, including their respective structures (shape and size). In this embodiment, the pivot point of the cutter unit 16 (axis L1: see Figure 5) is aligned with the center of the ring frame 20, and the cutting line (cutting line CL) is set so that the cutter 40 rotates around axis L1.

[0044] As shown in Figure 10, the adhesive tape 62 is attached to the upper surfaces of both the wafer W and the ring frame 20. During cutting, the cutter 40 and roller 43 are positioned above the ring frame 20, sandwiching the adhesive tape 62 between them. The roller 43 holds the adhesive tape 62 down from above, allowing the cutter 40 to cut steadily.

[0045] Figure 11 schematically illustrates phenomena that may occur during the cutting process. Figures 11(A) to (C) show the relationship between the contact pattern of the rotating blade and the cutting trajectory. The upper part of each figure shows a side view, and the lower part shows a top view. For the sake of clarity, the phenomena that may occur in this figure are exaggerated. As shown in Figure 11(A), when the cutter 40 descends and ideally makes contact with the cutting line CL, that is, when the blade surface of the cutter 40 makes contact parallel to the vertical plane, the cutter 40 rotates along the cutting line CL. As a result, the starting point Ps and ending point Pf of the cutting trajectory coincide on the cutting line CL, allowing the adhesive tape 62 to be cut in an ideal circular shape, and no whisker-like residue is produced.

[0046] On the other hand, as shown in Figure 11(B), when the cutter 40 descends and makes contact with the inside of the cutting line CL, that is, when the cutting surface of the cutter 40 is tilted to one side with respect to the vertical plane, the cutter 40 begins to rotate with the inside of the cutting line CL as the starting point Ps of the cutting trajectory. The cutter 40 moves towards the cutting line CL while correcting its posture by rotating around the axis L2. At this time, the cutter 40 reaches the cutting line CL by following a trajectory that expands radially around the axis L (the center O of the wafer W and ring frame 20), and thereafter moves along the cutting line CL.

[0047] Therefore, when the cutter 40 completes one rotation, it passes outside the starting point Ps, and then turns further to reach the endpoint Pf on the cutting line CL. As a result, a whisker-like residue Rb is generated in the region between the starting point Ps and the endpoint Pf of the adhesive tape 62 and remains on the ring frame 20 side. In other words, the conventional problem described above occurs.

[0048] As shown in Figure 11(C), when the cutter 40 descends and makes contact with the outside of the cutting line CL, that is, when the cutting surface of the cutter 40 is tilted to the opposite side of the vertical plane, the cutter 40 begins to rotate with the outside of the cutting line CL as the starting point Ps of the cutting trajectory. The cutter 40 moves towards the cutting line CL while correcting its posture by rotating around the axis L2. At this time, the cutter 40 reaches the cutting line CL by following a trajectory that moves radially inward around the axis L, and thereafter moves along the cutting line CL.

[0049] Therefore, when the cutter 40 completes one rotation, it passes inside the starting point Ps, and then turns further to reach the endpoint Pf on the cutting line CL. In this case, a whisker-like residue Rb is generated in the region between the starting point Ps and the endpoint Pf of the adhesive tape 62, but since it remains on the cut end side of the adhesive tape 62, the conventional problem does not occur. However, the cutter 40 must be moved by an amount equivalent to the distance between the starting point Ps and the endpoint Pf.

[0050] In reality, when the cutter 40 is placed on the ring frame 20, it tends to tilt due to the reaction force and frictional force from the ring frame 20, making it difficult to expect the ideal state (Figure 11(A)). This embodiment solves this problem.

[0051] Figure 12 is a schematic diagram illustrating the method of cutting adhesive tape according to the embodiment. Figure 12(A) shows a side view, and Figure 12(B) shows a top view. As shown in Figure 12(A), when the cutter 40 is lowered and made contact with the adhesive tape 62, a linear cut Nc is made in the adhesive tape 62 centered on the lowest point Po of the cutter 40 (exaggerated in the figure). The length of this cut Nc (length in the cutting direction) is defined as the cut length Lc.

[0052] As shown in Figure 12(B), the cutting line CL of the adhesive tape 62 is set along the surface of the ring frame 20. In this embodiment, the cutter 40 is deliberately positioned to make contact with the outside of the cutting line CL to prevent the cutting state shown in Figure 11(B), that is, the state in which the cutter 40 makes contact with the inside of the cutting line CL. Specifically, in the example shown in Figure 12(B), the table 10 is moved so that the contact position Cp is located at a distance X0 (for example, a few millimeters) to the left (outward from the cutting line CL) from the starting point C0 (initial position) on the cutting line CL (also called the "offset position"). In other words, the table 10 is moved so that the pivot center of the cutter unit 16 is shifted by a distance X0 from the center O of the ring frame 20. Then, the cutter 40 is lowered and made contact with the ring frame 20 so as to penetrate the adhesive tape 62. In the illustrated example, the cutter 40 is tilted slightly inward (see Figure 11(B)). At this time, the cut depth Nc extends in the X direction.

[0053] Next, the cutter 40 and the ring frame 20 are moved relative to each other (translated) so that the cutter 40 is directed from the cutting position Cp towards the cutting line CL. Specifically, the table 10 is moved in the X direction so that the center O of the ring frame 20 and the X-direction position of the cutter 40 coincide. In other words, by aligning the pivot center of the cutter 40 with the center of the table 10, the cutter 40 is moved to the starting point C0 on the cutting line CL. As the cutter 40 moves from the cutting position Cp to the starting point C0, its orientation is corrected by rotational inertia. After that, the cutter 40 is made to rotate along the cutting line CL.

[0054] At this time, the cutter 40 rotates at a predetermined angle of less than 360 degrees around its pivot center, that is, less than one full rotation along the cutting line CL, and reaches the endpoint Cn on the cutting line CL. In this embodiment, this pivot center coincides with the center O of the wafer W and the ring frame 20, but also coincides with the center of the table 10. As shown in the figure, the cut Nc at the endpoint Cn intersects with the cutting trajectory from the blade contact position Cp to the starting point C0. Therefore, the adhesive tape 62 attached to the wafer W can be cut in a circular shape. In other words, the travel distance of the cutter 40 from the blade contact position Cp to the starting point C0 (relative movement distance) is set so that the cutting trajectory from the blade contact position Cp to the starting point C0 intersects with the cutting trajectory near the endpoint on the cutting line CL.

[0055] Figure 13 is a flowchart illustrating the process of cutting adhesive tape. The control unit 50 drives the tape application unit 14 (tape supply mechanism 26) described above and operates the press roller 32 to apply the adhesive tape 62 to the wafer W and ring frame 20 placed on the table 10 (S10). At this time, the adhesive tape 62 is applied so as to cover the wafer W and ring frame 20. The cutter 40 is waiting above the adhesive tape 62. As described above, the cutting line CL of the adhesive tape 62 is set in advance along the surface of the ring frame 20.

[0056] Next, the control unit 50 moves the table 10 to an offset position (S12), then lowers the cutter 40 to engage the cutting position on the ring frame 20 (S14: cutting step). As a result, the cutter 40 engages the cutting position outside the cutting line CL.

[0057] Subsequently, the control unit 50 drives the table 10 to move the cutter 40 to the starting point C0 on the cutting line CL (S16: movement step). At this time, the cutter 40 and the ring frame 20 move relative to each other (translate) in the tangential direction of the cutting line CL. When the cutter 40 reaches the starting point C0, the control unit 50 cuts the adhesive tape 62 by making the cutter 40 rotate along the cutting line CL (S18: cutting step).

[0058] When the cutter 40 reaches the endpoint Cn on the cutting line CL (Y in S20), the control unit 50 stops the movement of the cutter 40 (S22). Then, it drives the lifting mechanism 42 to raise the cutter 40 and detach it from the adhesive tape 62 (S24). After that, the control unit 50 drives the tape retrieval mechanism 28 to perform the winding process of the adhesive tape 62 (S26).

[0059] As described above, in this embodiment, the cutter 40 is deliberately positioned to make contact with the outside of the cutting line CL. Then, the cutter 40 is moved parallel to the starting point C0 on the cutting line CL and made to rotate along the cutting line CL from the starting point C0. By setting the distance between the contact position Cp and the starting point C0, the cutting trajectory from the contact position Cp to the starting point C0 intersects with the cutting trajectory near the endpoint Cn on the cutting line CL. This prevents the formation of whisker-like residue on the outer circumference of the adhesive tape 62 attached to the wafer W. Cutting efficiency can also be increased by setting the distance from the contact position Cp of the cutter 40 to the starting point C0 to the minimum necessary.

[0060] Although preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these specific embodiments, and various modifications are possible within the scope of the technical concept of the present invention.

[0061] [Differentiation] Figure 14 shows a modified example of how to cut adhesive tape. In the above embodiment, the cutter 40 (rotating blade) is positioned outside the cutting line CL, and the ring frame 20 and the cutter 40 are moved in parallel (initial movement) to bring the cutter 40 to the starting point on the cutting line CL. Subsequently, the cutter 40 is made to rotate along the cutting line CL.

[0062] In a modified example, the rotating blade may be made to bite outside the cutting line CL without the initial movement (parallel movement) described in the above embodiment, and then rotated (swiveled) from that bite position Cp. When the rotating blade has completed one rotation, or when it reaches a predetermined endpoint Cn in its vicinity, the ring frame 20 and the cutter 40 may be moved in parallel by the movement of the table 10. Even when this method is adopted, the rotating blade will cut the cutting trajectory from the inside outwards near the endpoint. This prevents the formation of whisker-like residue on the outer circumference of the adhesive tape 62.

[0063] The adhesive tape cutting method related to this modified example can be expressed as follows. A cutting method for cutting an adhesive tape, which is attached to cover the surface of a ring frame placed on the outside of a wafer, along the surface of the ring frame using a rotating blade, A cutting line for the adhesive tape is set along the surface of the ring frame. A cutting step in which the rotating blade is brought into contact with the starting point or nearby on the cutting line, A movement step in which the rotating blade is moved along the cutting line by moving the rotating blade and the ring frame relative to each other, A method for cutting adhesive tape, comprising: a cutting step in which, when the rotating blade reaches an endpoint position set on the cutting line, the rotating blade and the ring frame are moved in parallel to intersect the cutting trajectory.

[0064] Combining this modified example with the concept of the above embodiment, it can be expressed, for example, as follows. A cutting method for cutting an adhesive tape, which is attached to cover the surface of a ring frame placed on the outside of a wafer, along the surface of the ring frame using a rotating blade, A cutting line for the adhesive tape is set along the surface of the ring frame. A cutting step in which the rotating blade is attached to the adhesive tape, A movement step of moving the rotating blade and the ring frame relative to each other toward the cutting line, A method for cutting adhesive tape, comprising a cutting step of rotating the aforementioned rotating blade in a circular motion along the cutting line from a starting point on the cutting line.

[0065] Figure 15 shows a diagram illustrating a method for cutting adhesive tape related to another modified example. In this modified example, after the rotary blade is positioned outside the cutting line CL, the linear movement of the table 10 and the rotation (rotational movement) of the cutter 40 are synchronized. Specifically, after positioning the rotary blade at a predetermined location (X,Y) near the cutting line CL, the initial movement involves spirally moving the rotary blade towards the starting point C0 to approach the cutting line CL (Figure 15(A)). Thereafter, as in the above embodiment, the rotary blade is moved in a circular motion along the cutting line CL from the starting point C0 (Figure 15(B)). This prevents the formation of whisker-like residue on the outer circumference of the adhesive tape 62. According to this modified example, the initial movement stroke can be secured, for example, when the width of the ring frame 20 is small relative to the rotary blade, or when the outer diameter r of the ring frame 20 is small. In order to secure the initial movement stroke, the cutter 40 may be positioned outside the ring frame 20, for example, on the table 10.

[0066] [Other variations] In the above embodiment, a ring frame 20 and a wafer W are arranged concentrically on a table 10, and an adhesive tape 62 is attached to cover both the ring frame 20 and the wafer W, and then cut in a circular shape along the ring frame 20. In a modified example, the adhesive tape may be attached to the ring frame, cut in a circular shape by a cutting device, and then the wafer may be attached to the adhesive tape. The wafer is attached to the adhesive tape so as to be concentric with the ring frame.

[0067] In the above embodiment, as shown in Figure 6, etc., a configuration in which a cutter 40 is provided at one end of the rotating arm 116 and a roller 43 at the other end was illustrated. In a modified example, another cutter 40 may be provided instead of the roller 43, that is, a configuration in which cutters 40 are provided at both ends of the rotating arm 116 may be adopted.

[0068] In the above embodiment, as shown in Figure 9, an example is shown in which the cutter 40 (rotating blade) and roller 43 are arranged at one end and the other end of the rotating arm 116, respectively, so as to be symmetrical with respect to the rotation axis 110. In modified examples, at least one of the rotating blade and roller may be provided in multiples. For example, the rotating arm may have a three-pronged or cross structure (radial shape around the rotation axis) in plan view, and the rotating blade or roller may be attached to the tips thereof.

[0069] In the above embodiment, a configuration is shown in which the centers (axes) of the wafer W, ring frame 20, and table 10 coincide. In modified examples, the centers of any of these do not necessarily coincide. In that case as well, the rotational trajectory of the cutter 40 is kept within the range on the ring frame 20.

[0070] In the above embodiment, an example was shown in which the cutter 40 is positioned so that its pivot center is offset to the left by a distance X0 from the center of the ring frame 20. In a modified example, the cutter 40 may be positioned so that its pivot center is offset by a predetermined distance from the center of the table 10. Alternatively, the cutter 40 may be positioned so that its pivot center is offset by a predetermined distance from the center of the wafer W. In any case, the cutter 40 is ultimately positioned at an offset location from the starting point (initial position) on the cutting line CL. This offset positions the cutter 40 outside the cutting line CL.

[0071] In the above embodiment, an example was shown in which the adhesive tape 62 is cut by controlling the rotational movement (swivel) of the cutter 40 and the linear movement of the table 10 in a horizontal plane (XY plane) where the ring frame 20 and adhesive tape 62 exist. In a modified example, the cutter 40 may be configured to move within the horizontal plane. For example, the cutter 40 may be controlled to move radially relative to the rotating arm 116 (see Figure 5). Alternatively, the rotating arm 116 may be made to move relative to the frame 102. Then, the cutter 40 may be moved within the horizontal plane after being brought to the outside of the cutting line CL, gradually approaching the starting point on the cutting line.

[0072] It should be noted that the present invention is not limited to the embodiments and modifications described above, and the components can be modified and implemented without departing from the spirit of the invention. Various inventions may be formed by appropriately combining the multiple components disclosed in the embodiments and modifications described above. In addition, some components may be deleted from all the components shown in the embodiments and modifications described above. [Explanation of Symbols]

[0073] 1 Cutting device, 10 Table, 12 Table movement mechanism, 14 Tape application unit, 16 Cutter unit, 18 Chuck unit, 20 Ring frame, 26 Tape supply mechanism, 28 Tape recovery mechanism, 30 Supply section, 32 Press roller, 34 Winding section, 36 Recovery section, 40 Cutter, 42 Lifting mechanism, 43 Roller, 44 Rotation mechanism, 50 Control unit, 52 Guide roller, 54 Feed roller, 56 Guide roller, 58 Raw material roll, 62 Adhesive tape, 64 Separator, 66 Tape raw material, 68 Feed roller, 70 Guide roller, 72 Peel plate, 74 Roll, 80 Guide roller, 82 Feed roller, 84 Guide roller, 88 Pressing roller, 90 Roll, 92 Frame table, 94 Chuck table, 96 Holding plate, 98 Suction surface, 100 Base, 102 Frame, 104 linear guide, 106 screw feed mechanism, 108 servo motor, 110 rotating shaft, 112 motor, 114 belt, 116 rotating arm, 120 rotating unit, 122 housing, 128 pulley, 134 cylinder mechanism, 135 cylinder, 136 movable member, 140 support member, 144 support member, 150 screw, 152 screw hole, 154 grub screw, C0 start point, CL cutting line, Cn end point, Cp contact position, Nc depth of cut, O center, PA adhesion area, Rb residue, W wafer.

Claims

1. A cutting method for cutting an adhesive tape, which is attached to cover the surface of a ring frame placed on the outside of a wafer, along the surface of the ring frame using a rotating blade, A cutting line for the adhesive tape is set along the surface of the ring frame. A cutting step in which the rotating blade is placed on the cutting line at a cutting position offset by a predetermined distance from the position where the rotating blade is placed, A movement step of moving the rotating blade and the ring frame relative to each other so that the rotating blade is directed from the cutting position toward the cutting line, A method for cutting adhesive tape, comprising a cutting step of rotating the aforementioned rotating blade in a circular motion along the cutting line from a starting point on the cutting line.

2. The method for cutting adhesive tape according to claim 1, wherein the cutting step involves setting the relative movement distance such that the cutting trajectory from the blade contact position to the starting point intersects with the cutting trajectory near the endpoint on the cutting line.

3. The adhesive tape cutting method according to claim 1 or 2, wherein the blade-attaching step involves attaching the rotating blade to the outside of the cutting line.

4. The adhesive tape cutting method according to claim 3, wherein the moving step involves moving the rotating blade and the ring frame in parallel in the tangential direction of the cutting line.

5. The method for cutting adhesive tape according to claim 3, wherein the moving step involves moving the rotating blade spirally toward the starting point and approaching the cutting line.

6. A table on which to place the wafer and the ring frame such that the ring frame is positioned outside the wafer, A tape supply mechanism for applying adhesive tape to cover the wafer and the ring frame, A rotating blade that is rotatably supported, A moving mechanism is provided to allow relative movement between the rotating blade and the table, The system comprises a control unit that controls the rotating blade and the table, A cutting line for the adhesive tape is set along the surface of the ring frame. The control unit places the rotating blade on the cutting line at a position offset by a predetermined distance from the position where the rotating blade is placed on the cutting line, moves the rotating blade and the ring frame relative to each other so that the rotating blade faces the cutting line from the placement position, and moves the rotating blade in a circular motion along the cutting line from the starting point on the cutting line, in an adhesive tape cutting device.

7. The adhesive tape cutting device according to claim 6, wherein the control unit, by setting the relative movement distance, causes the cutting trajectory from the blade contact position to the starting point to intersect with the cutting trajectory near the endpoint on the cutting line.

8. The adhesive tape cutting device according to claim 7, wherein the control unit causes the rotating blade to be attached to the outside of the cutting line.

9. The adhesive tape cutting apparatus according to claim 8, wherein the moving mechanism moves the rotating blade and the table in parallel in the tangential direction of the cutting line.

10. The adhesive tape cutting device according to claim 8, wherein the moving mechanism moves the rotating blade spirally toward the starting point and closer to the cutting line.

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