Braking device

Abstract

To provide a braking device capable of reducing costs and installation space by switching between a first dividing mechanism adopting a two-point support system and a second dividing mechanism adopting a three-point support system according to the material of a wafer.SOLUTION: A braking device 1, which divides a wafer W starting from a linear dividing point g formed on the wafer W having a sheet T attached to one side, includes a first dividing mechanism (two-point support method) that clamps the wafer W from above and below along the dividing point g and presses the other side of the wafer W at a position a predetermined distance away from the position where the wafer W is clamped, thereby dividing the wafer W starting from the dividing point g, and a second dividing mechanism (second support method) that supports one side of the wafer W at two points sandwiching the dividing point g and presses the dividing point g from the other side, thereby dividing the wafer W starting from the dividing point g.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a breaking device for dividing a wafer along a dividing starting point. [Background technology]

[0002] For example, in the manufacturing process of semiconductor devices, the surface of a disk-shaped semiconductor wafer (hereinafter simply referred to as a "wafer") is divided into a plurality of device regions by planned dividing lines called streets formed in a grid pattern, and devices such as ICs and LSIs are formed in each device region. Then, a plurality of chips are obtained by dividing the wafer on which a large number of devices have been formed along the planned dividing lines.

[0003] As a method for dividing a silicon wafer along a planned dividing line, Patent Document 1 proposes a method in which a tape attached to a silicon wafer in which a modified layer has been formed by irradiation with a laser beam is expanded, thereby dividing the silicon wafer starting from the modified layer.

[0004] However, even with the above method, it is difficult to divide the wafer by expanding the tape when the wafer is made of a hard material (highly hard crystalline material) such as silicon carbide (SiC) or sapphire. For this reason, Patent Document 2 proposes a breaking device that employs a three-point support method in which the lower surface of the wafer, which sandwiches a V-groove formed on the surface of the wafer that serves as the starting point for dividing the wafer, is supported by two support stages, and a blade is pressed directly above the starting point for dividing the wafer on the upper surface of the wafer, and the wafer is divided along the starting point for dividing while being supported at three points by the two support stages and the blade.

[0005] Furthermore, Patent Document 3 proposes a breaking device that employs a two-point support method in which a wafer is clamped between two clamping bars, supporting it at two points from above and below, and a blade is pressed against the top surface of the wafer at a predetermined distance from a modified layer formed inside the wafer, which serves as the starting point for dividing the wafer, to divide the blade along the starting point for dividing. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-140266 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-058671 [Patent Document 3] Japanese Patent Publication No. 2024-027963 Summary of the Invention [Problem to be solved by the invention]

[0007] However, dividing wafers made of hard materials such as silicon carbide (SiC) or sapphire requires a large force, and when the dividing starting point is a modified layer formed inside the wafer, a two-point support method using the principle of leverage is used. On the other hand, when the dividing starting point is a V-groove formed on the wafer surface, a three-point support method is used. Therefore, it is necessary to prepare a breaking device that uses the two-point support method and a breaking device that uses the three-point support method. Preparing two breaking devices with different dividing methods like this increases equipment costs, leading to increased costs, and also results in a problem of requiring a large installation space for the devices.

[0008] The present invention has been made in consideration of the above problems, and its purpose is to provide a braking device that can reduce costs and installation space by switching between a first split mechanism that uses a two-point support system and a second split mechanism that uses a three-point support system. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the present invention is a breaking device that divides a wafer starting from a linear dividing point formed on a wafer having a sheet attached to one side, and is characterized by comprising: a first dividing mechanism that clamps the wafer from above and below along the dividing point and presses the other side of the wafer at a position a predetermined distance from the position where the wafer is clamped, thereby dividing the wafer starting from the dividing point; and a second dividing mechanism that supports one side of the wafer at two points on either side of the dividing point and presses the dividing point from the other side, thereby dividing the wafer starting from the dividing point. [Effects of the Invention]

[0010] According to the present invention, the switching control unit switches the dividing method between a two-point support method (first dividing mechanism) and a three-point support method (second dividing mechanism) depending on the material of the wafer to be divided. The two-point support method (first dividing mechanism) is selected for dividing wafers that have a modified layer formed as the dividing starting point, as this requires a large force, and the three-point support method (second dividing mechanism) is selected for dividing wafers that have a groove formed on the surface as the dividing starting point. This eliminates the need to prepare two breaking devices that use different dividing methods, thereby reducing equipment costs and achieving cost savings, as well as reducing the installation space required for the device. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view of a braking device according to the present invention; [Figure 2] FIG. [Figure 3] FIG. 2 is a perspective view of a support bar mechanism of the braking device according to the present invention. [Figure 4] 1 is a side cross-sectional view of a main part of a braking device according to the present invention. [Figure 5] FIG. 4 is a partial cross-sectional side view showing a holding process of a first divided mechanism (two-point support type) of the braking device according to the present invention. [Figure 6]4 is a partial cross-sectional side view showing a separating process of a first separating mechanism (two-point support type) of the braking device according to the present invention. FIG. [Figure 7] FIG. 10 is a partial cross-sectional side view showing a holding process of the second divided mechanism (three-point support type) of the braking device according to the present invention. [Figure 8] 10 is a partial cross-sectional side view showing a separating process of a second separating mechanism (three-point support type) of the braking device according to the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0013] [Braking device configuration] First, the configuration of the braking device according to the present invention will be described. In the following description, the arrow directions shown in Fig. 1 are the X-axis (left-right direction), the Y-axis (front-rear direction), and the Z-axis (up-down direction), respectively.

[0014] The breaking device 1 shown in Fig. 1 is a device for dividing a wafer W shown in Fig. 2. The wafer W to be divided includes materials that are relatively easy to break, such as single-crystal silicon (Si), and materials that require a large force to break, such as hard silicon carbide (SiC), glass, ceramics, and sapphire. The surface of this wafer W (the upper surface in Fig. 2) is partitioned into a plurality of rectangular regions by dividing lines L1 and L2, called streets, which are arranged in a grid pattern and intersect each other at right angles, and devices D, such as ICs and LSIs, are formed in each rectangular region.

[0015] As described above, the wafer W having a large number of devices D formed on its surface is incorporated into the work set WS shown in Fig. 2, and the wafer W is divided along the intended dividing lines L1, L2 by the breaking device 1 according to the present invention. Here, the work set WS is configured by bonding the back surface (lower surface) of the disk-shaped wafer W to a sheet T that is attached to a metal (e.g., SUS) ring frame F, covering the circular opening of the ring frame F, thereby supporting the wafer W on the ring frame F via the sheet T, and integrating the wafer W, ring frame F, and sheet T.

[0016] 1 comprises, as its main components, a rectangular frame-shaped holding table 10 that holds the ring frame F of the work set WS, a support bar mechanism 30 arranged inside the holding table 10, a blade mechanism 70 provided on a portal column 110 that is erected vertically on a base 100, and a switching control unit 90. Below, the configurations of the main components of the braking device 1, namely the holding table 10, the support bar mechanism 30, the blade mechanism 70, and the switching control unit 90, will be described respectively.

[0017] (holding table) Rectangular frame-shaped holding table 10 is rotatably mounted on slider 21 of horizontal movement mechanism 20, and two fixed clamps 11 and two movable clamps 12 are arranged on its upper surface in two mutually orthogonal directions (X-axis direction and Y-axis direction). Here, each fixed clamp 11 is fixed to the upper surface of holding table 10, and each movable clamp 12 has a pressing element 12a that can move in two mutually orthogonal directions (directions of arrows in the figure).

[0018] Thus, the holding table 10 can be rotated about a vertical central axis by a rotation mechanism (not shown), and can be moved back and forth along the Y-axis direction by a horizontal movement mechanism 20. Here, the horizontal movement mechanism 20 is configured to include a pair of guide rails 22 laid parallel to each other along the Y-axis direction on the base 100, a rectangular plate-shaped slider 21 that can move along these guide rails 22, a rotatable ball screw 23 that is arranged along the Y-axis direction on the side of one of the guide rails 22 (in the +X-axis direction), and a servo motor 24 that is a rotational drive source that can rotate forward and backward and is connected to one axial end of the ball screw 23. The other axial end of the ball screw 23 is rotatably supported by the base 100 via a bearing (not shown).

[0019] A rectangular block-shaped nut member 25 is attached to one side of the slider 21, and a ball screw 23 is threadedly inserted into the nut member 25. Therefore, when the servo motor 24 is started to rotate the ball screw 23 forward or backward, the slider 21, to which the nut member 25 that threads onto the ball screw 23 is attached, can move back and forth in the Y-axis direction along the pair of guide rails 22. Therefore, the holding table 10 supported by the slider 21 can also move back and forth in the Y-axis direction.

[0020] (Support bar mechanism) As shown in Figure 3, the support bar mechanism 30 arranged inside the holding table 10 includes four first support bars 31 and four second support bars 32 of different lengths arranged in a cross shape at equal angular pitches (90° pitches) circumferentially, a support bar rotation mechanism 40 that intermittently rotates these first support bars 31 and second support bars 32 by 90° increments, a support bar lifting mechanism 50 that raises and lowers the first support bars 31 and second support bars 32 in the Z-axis direction, and a support bar horizontal movement mechanism 60 (see Figure 4) that moves the first support bars 31 and second support bars 32 horizontally in the Y-axis direction.

[0021] Here, the four first support bars 31 and the four second support bars 32 are rectangular plate-shaped members that are long in the X-axis direction, and each first support bar 31 is attached radially to the outer periphery of a rotatable rotation shaft 41 that is disposed along the X-axis direction. The four second support bars 32 are disposed in rectangular recesses 41a that are formed along the X-axis direction at four locations around the circumference of the rotation shaft 41, and each second support bar 32 can be raised and lowered in the Z-axis direction by a single support bar lifting mechanism 33 and can move horizontally in the Y-axis direction by a support bar spacing adjustment mechanism 34. Note that in this embodiment, a configuration is adopted in which the second support bar 32 can be raised and lowered in the Z-axis direction by the single support bar lifting mechanism 33 and can move horizontally in the Y-axis direction by the support bar spacing adjustment mechanism 34, but a configuration in which the first support bar 31 can be raised and lowered in the Z-axis direction and can move horizontally in the Y-axis direction may also be adopted.

[0022] Here, the rotating shaft 41 is rotatably supported by a frame 42, and a driven gear 43 is attached to one axial end (+X-axis end) protruding from the frame 42. A switching electric motor 44, which serves as a rotation drive source, is attached in a horizontally placed state to one end of the frame 42 (the side where the driven gear 43 is provided). A drive gear 45 is attached to the end of an output shaft (motor shaft, not shown) that extends horizontally from the electric motor 44 and penetrates one side of the frame 42, and the drive gear 45 and the driven gear 43 are in mesh with each other. In this embodiment, the driven gear 43 and the drive gear 45 have the same diameter.

[0023] Thus, the rotating shaft 41, electric motor 44, driven gear 43, drive gear 45, etc. constitute a support bar rotation mechanism 40 that rotates the four first support bars 31 and four second support bars 32. Therefore, when the electric motor 44 is started, the rotation of its output shaft (motor shaft) is transmitted to the rotating shaft 41 via the meshing drive gear 45 and driven gear 43, and the rotating shaft 41 and the four first support bars 31 and four second support bars 32 attached thereto intermittently rotate in increments of 90 degrees around the axis of the rotating shaft 41. The four first support bars 31 and four second support bars 32 each having different lengths are rotated in increments of 90 degrees by the support bar rotation mechanism 40, and one of the four first support bars 31 and four second support bars 32 is selected and used according to the length of the planned dividing lines L1, L2 (see FIG. 2) of the wafer W held on the holding surface of the holding table 10.

[0024] Furthermore, the support bar lifting mechanism 50 that raises and lowers each of the four first support bars 31 and four second support bars 32 includes a pair of guide rails 52 arranged along the Z-axis direction (up and down direction) on a vertically standing rectangular plate-shaped base 51, a rotatable ball screw 53 arranged along the Z-axis direction between these guide rails 52, and a servo motor 54 that serves as a rotational drive source connected to the lower end of the ball screw 53. The upper end of the ball screw 53 is rotatably supported by the base 51 via a bearing 55. Furthermore, a nut member (not shown) is attached to the frame 42, and the ball screw 53 is threadably inserted into the nut member.

[0025] Therefore, when the servo motor 54 is started to rotate the ball screw 53 forward and backward, the frame 42, to which a nut member (not shown) that threads onto the ball screw 53 is attached, rises and falls together with the rotating shaft 41 and the electric motor 44, etc., and the four first support bars 31 and four second support bars 32 attached radially to the rotating shaft 41 also rise and fall along the Z-axis direction.

[0026] (Blade mechanism) 1 and 4, the blade mechanism 70 is provided with a slider 73 that is bent in a horizontal L-shape, and a first blade 71 and a second blade 72 that are arranged parallel to each other along the Y-axis direction are vertically supported by the slider 73. Here, the first blade 71 is a plate member that is bent in an inverted L-shape, and its lower end forms, for example, a sharp knife edge. In addition, a blade spacing adjustment mechanism 74 is interposed between the first blade 71 and the slider 73.

[0027] Furthermore, the vertical second blade 72, which is disposed adjacent to the first blade 71 and parallel to it along the X-axis direction (the direction perpendicular to the plane of the paper in FIG. 4 ), is a plate member bent in an inverted L shape, and a shaft 72a extending upward from its upper end passes vertically through the slider 73. A single-blade lifting mechanism 75 that moves the second blade 72 up and down is attached to the shaft 72a. The single-blade lifting mechanism 75 also functions as a damper, and can be lifted and lowered independently of the slider 73 and the first blade 71. Furthermore, although the present embodiment employs a configuration in which the second blade 72 is lifted and lowered by the single-blade lifting mechanism 75, a configuration in which the first blade 71 is lifted and lowered may also be employed.

[0028] 1, the first blade 71 and the second blade 72 supported by the slider 73 can be raised and lowered in the Z-axis direction by a blade lifting mechanism 80, which includes a pair of guide rails 82 attached parallel to each other along the Z-axis direction to a vertical base 81 in the shape of a rectangular plate fixed to a portal column 110, a rotatable ball screw 83 arranged along the Z-axis direction between the guide rails 82, and a servo motor 84 serving as a rotational drive source connected to the upper end of the ball screw 83. The lower end of the ball screw 83 is rotatably supported by a base 100 via a bearing (not shown), and the ball screw 83 is threadedly inserted into a nut member (not shown) attached to the slider 73.

[0029] Therefore, when the servo motor 84 is started to rotate the ball screw 83 forward and backward, the slider 73, which is attached with a nut member (not shown) that screws onto the ball screw 83, moves up and down in the Z-axis direction along a pair of guide rails 82, and the first blade 71 and second blade 72 attached to the slider 73 move up and down integrally in the Z-axis direction.

[0030] (Switching control unit) The switching control unit 90 switches the division method (division mechanism) between a first division mechanism employing a two-point support method shown in Figures 5 and 6 or a second division mechanism employing a three-point support method shown in Figures 7 and 8, depending on the shape of the division starting point, for example. As shown in Figure 4, this switching control unit 90 controls the operations of the single support bar lifting mechanism 33 of the support bar mechanism 30, the support bar spacing adjustment mechanism 34, the blade spacing adjustment mechanism 74 of the blade mechanism 70, and the single blade lifting mechanism 75, thereby switching the division method between the first division mechanism employing a two-point support method shown in Figures 5 and 6 or the second division mechanism employing a three-point support method shown in Figures 7 and 8, the details of which will be described later.

[0031] (Other configurations) When dividing the wafers W along the planned dividing lines L1, L2 (see FIG. 2), as shown in FIG. 4, the ring frame F of the work set WS carrying the wafers W is placed on the holding table 10, and the ring frame F of the work set WS is held on the holding table 10 by two fixed clamps 11 and two movable clamps 12, with a protective film f interposed between the wafers W of the work set WS and the first and second blades 71, 72. Here, the protective film f is pulled out from a state in which it is wound around the supply-side roll R1 and is taken up by the take-up-side roll R2, and the protective film f between the two rolls R1, R2 is pressed by the four guide rollers r and the first and second blades 71, 72, and is in a tensioned state above the wafers W.

[0032] [Action of braking device] Next, a method for dividing a wafer W using the breaking apparatus 1 configured as described above will be described. The breaking apparatus 1 according to this embodiment is characterized in that the dividing method (dividing mechanism) is switched by the switching control unit 90 depending on the material of the wafer W to be divided. Specifically, the two-point support method (first dividing mechanism) shown in FIGS. 5 and 6 is selected for dividing a wafer W having a modified layer formed therein as a dividing starting point, and the three-point support method (second dividing mechanism) shown in FIGS. 7 and 8 is selected for dividing a wafer W having a V-shaped groove formed on its surface as a dividing starting point. Specifically, the switching control unit 90 controls the operation of the single support bar lifting mechanism 33 and the support bar spacing adjustment mechanism 34 of the support bar mechanism 30, and also controls the operation of the blade spacing adjustment mechanism 74 and the single blade lifting mechanism 75 of the blade mechanism 70, thereby switching the dividing method between the two-point support method (first dividing mechanism) and the three-point support method (second dividing mechanism), depending on the material of the wafer W to be divided.

[0033] Hereinafter, the methods of dividing the wafer W using the two-point support system (first dividing mechanism) and the three-point support system (second dividing mechanism) will be described.

[0034] 1) Two-point support method (first division mechanism): The division of the wafer W by the two-point support system (first dividing mechanism) is carried out according to the following procedure.

[0035] That is, as shown in Figure 5, the work set WS is placed on the holding table 10, and with the outer periphery of the ring frame F of the work set WS in contact with the two fixed clamps 11, the pressing elements 12a of the other two movable clamps 12 are moved inward toward the holding table 10 to press the outer periphery of the ring frame F against the two fixed clamps 11, thereby positioning the ring frame F, i.e., the work set WS, on the holding table 10 and holding it in place.

[0036] Inside the wafer W, dividing starting points g are formed in a grid pattern by modified layers along the dividing lines L1, L2 (see FIG. 2). That is, by focusing a laser beam having a wavelength that is transparent to the wafer W inside the wafer W and irradiating it along the dividing lines L1, L2, vertical modified layers are partially formed inside the wafer W along the dividing lines L1, L2, and these modified layers become dividing starting points g. Here, the modified layer refers to an area whose density, refractive index, mechanical strength, and other physical properties are different from those of the surrounding area.

[0037] As described above, with the work set WS held on the holding table 10, the first support bar 31 and the second support bar 32 are moved horizontally by the support bar horizontal movement mechanism 60, and the first support bar 31 is brought into contact with the underside of the wafer W at the position where the division starting point g is formed, via the sheet T, as shown in FIG. 5. At this time, the horizontal position of the wafer W relative to the second blade 72 is adjusted by horizontally moving the holding table 10 together with the wafer W in the Y-axis direction by the horizontal movement mechanism 20 shown in FIG. 1, and the second blade 72 is positioned above the division starting point g of the wafer W. At this time, the second support bar 32 is lowered by the single support bar lifting mechanism 33 and retracted below the wafer W. Therefore, the wafer W is supported at two points, top and bottom, by the second blade 72 and the first support bar 31 at the location of the division starting point g. In addition, the surface of the wafer W is imaged by an imaging unit (not shown), and the image obtained by imaging is processed by pattern matching or the like to detect the positions of the planned division lines L1, L2 (see Figure 2), i.e., the position of the division starting point g.

[0038] On the other hand, the first blade 71 is moved by the blade spacing adjustment mechanism 74 to a position a predetermined distance away from the second blade 72 in the -Y-axis direction, and in the state shown in Figure 5 before the wafer W is divided, the first blade 71 and the second blade 72 are positioned above the wafer W, and a protective film f pulled out from the supply side roll R1 is pressed between the first blade 71 and the second blade 72 and the wafer W by the four guide rollers r and the first blade 71 and the second blade 72, and is in a tensed state above the wafer W.

[0039] As shown in FIG. 5, when the wafer W is divided along the division starting point g, with the second blade 72 and the first support bar 31 supporting the wafer W at two points via the sheet T, the slider 73 is lowered by the blade lifting mechanism 80, and the first blade 71 and the second blade 72 supported by the slider 73 also descend, and the knife-edge-shaped lower end of the first blade 71 abuts against the upper surface of the wafer W at a position offset a predetermined distance in the -Y-axis direction from the division starting point g via the protective film f, and presses the upper surface with a predetermined force. In addition, the second blade 72 also descends together with the first blade 71 and abuts against the upper surface of the location where the dividing starting point g of the wafer W is formed via the protective film f, but this second blade 72 is held in a state where it is pressing with a constant force against the upper surface of the location where the dividing starting point g of the wafer W is formed via the protective film f due to the action of the single-blade lifting mechanism 75, which also functions as a damper, allowing the first blade 71 to descend relatively.

[0040] As described above, when the first blade 71 further descends relative to the second blade 72 while the wafer W is supported at two points by the second blade 72 and the first support bar 31 via the sheet T at the dividing starting point g, the first blade 71 presses against the upper surface of the wafer W via the protective film f at a position a predetermined distance away from the dividing starting point g of the wafer W, and a bending moment due to the pressing force of the first blade 71 generates a bending stress at the dividing starting point g of the wafer W. Therefore, this bending stress effectively divides the wafer W starting from the dividing starting point g. Note that the wafer W may also be divided by turning the wafer W upside down and raising the first blade 71 from below the wafer W to push up the wafer W and generate a bending stress at the dividing starting point g.

[0041] 6, the upper surface of the wafer W, including the division starting points g, which are the division locations of the wafer W to be divided as described above, is covered with a protective film f, so that the devices D are protected by the protective film f and the protective film f also prevents the scattering of division powder caused by the division of the wafer W to the surrounding area. Note that division may be performed without using the protective film f.

[0042] In addition, when an ultrasonic vibrator is provided on the first blade 71 and the first blade 71 is ultrasonically vibrated by this ultrasonic vibrator, the wafer W is reliably fractured and divided starting from the dividing starting point g by brittle fracture (fatigue fracture due to repeated stress) caused by the vibration energy transmitted from the first blade 71.

[0043] When division along the dividing lines L1 in one direction is completed, the horizontal movement mechanism 20 shown in FIG. 1 moves the holding table 10 and the wafer W held thereon by one pitch (the distance between adjacent dividing lines L1) in the Y-axis direction (indexing direction), and similar division of the wafer W is performed along the next dividing line L1. When division of the wafer W along all of the dividing lines L1 in one direction is completed, the holding table 10 and the wafer W (work set WS) held thereon are rotated by an angle of 90 degrees around a vertical axis by a rotation mechanism (not shown), and division is similarly performed along dividing lines L2 in the other direction that are perpendicular to the one dividing line L1. When the wafer W has been divided along all of the dividing lines L2 in the other direction, the series of division operations for the wafer W is completed, and a plurality of chips are obtained by dividing the wafer W.

[0044] 2) Three-point support system (second split mechanism): Next, the division of the wafer W by the three-point support system (second dividing mechanism) will be described below with reference to FIGS.

[0045] As in the case of separation using the two-point support method (first separation mechanism), the work set WS is fixed and held on the holding table 10. That is, as shown in Fig. 7, the work set WS is placed on the holding table 10, and with the outer periphery of the ring frame F of the work set WS abutting against the two fixed clamps 11, the pressing elements 12a of the other two movable clamps 12 are moved inward toward the holding table 10 to press the outer periphery of the ring frame F against the two fixed clamps 11, thereby holding the ring frame F, that is, the work set WS, in a position on the holding table 10. Note that in the state shown in Fig. 7 (the state before the wafer W is separated), a protective film f pulled out from a supply-side roll R1 is pressed between the first blade 71, the second blade 72, and the wafer W by the four guide rollers r and the first blade 71 and second blade 72, and is in a tensioned state above the wafer W.

[0046] In the support bar mechanism 30, the second support bar 32 is moved horizontally by the support bar spacing adjustment mechanism 34 in a direction away from the first support bar 31 (to the left in FIG. 7 ) to ensure a predetermined distance between it and the first support bar 31, and the second support bar 32 is raised to the same height as the first support bar 31 by the single support bar lifting mechanism 33. Then, from this state, the entire support bar mechanism 30 is moved horizontally by the support bar horizontal movement mechanism 60 to the location where the division starting point g of the wafer W is formed, and the entire support bar mechanism 30 is raised by the support bar lifting mechanism 50, so that the first support bar 31 and the second support bar 32 come into contact with the underside of the wafer W at two locations on either side of the division starting point g, with the sheet T interposed therebetween.

[0047] When dividing the wafer W along the dividing starting point g from a state in which the first support bar 31 and the second support bar 32 are in contact with each other via the sheet T at two points on either side of the dividing starting point g on the underside of the wafer W as shown in FIG. 7, the blade spacing adjustment mechanism 74 moves the first blade 71 horizontally in a direction approaching the second blade 72 (in the direction of the arrow in FIG. 7), and as shown in FIG. 8, the sharp-edged tip of the first blade 71 is positioned at the location on the upper surface of the wafer W where the dividing starting point g is formed.

[0048] When the slider 73 is lowered by the blade lifting mechanism 80 from the above state, the first blade 71 and the second blade 72 supported by the slider 73 also lower, and the knife-edge-shaped tip of the first blade 71 abuts against the portion of the upper surface of the wafer W where the division starting points g are formed, via the protective film f, and presses against the upper surface with a predetermined force. In response to this, the second blade 72 is raised by the single-blade lifting mechanism 75 and, as shown in Fig. 8, is separated from the wafer W and retracted above the wafer W. Therefore, three points on the portion of the wafer W where the division starting points g are formed are supported by the first blade 71, the first support bar 31, and the second support bar 32.

[0049] As described above, when the slider 73 and first blade 71 are further lowered by the blade lifting mechanism 80 while the wafer W is supported at three points by the first blade 71, the first support bar 31, and the second support bar 32 at the location where the division origin g is formed, a bending stress is generated at the division origin g of the wafer W due to a bending moment caused by an upward reaction force (normal force) acting on the first support bar 31 and the second support bar 32, and this bending stress causes the wafer W to be divided starting from the division origin g. Also in this case, when an ultrasonic vibrator is provided on the first blade 71 and the first blade 71 is ultrasonically vibrated by this ultrasonic vibrator, the wafer W is reliably cleaved and divided starting from the division origin g due to brittle fracture (fatigue fracture due to repeated stress) caused by vibration energy propagated from the first blade 71. Alternatively, the wafer W may be turned upside down and the first blade 71 may be raised from below the wafer W to push up the wafer W and generate bending stress at the dividing starting point g, thereby dividing the wafer.

[0050] Also, in this three-point support system (second dividing mechanism), the top surface including the dividing starting point g, which is the dividing portion of the wafer W to be divided as described above, is covered with a protective film f as shown in Fig. 8, so that the device D is protected by the protective film f and the protective film f also prevents scattering of dividing powder caused by dividing the wafer W to the surrounding area. Note that dividing may be performed without using the protective film f.

[0051] When division along the dividing lines L1 in one direction is completed, the horizontal movement mechanism 20 shown in FIG. 1 moves the holding table 10 and the wafer W held thereon by one pitch (the distance between adjacent dividing lines L1) in the Y-axis direction (indexing direction), and similar division of the wafer W is performed along the next dividing line L1. When division of the wafer W along all of the dividing lines L1 in one direction is completed, the holding table 10 and the wafer W (work set WS) held thereon are rotated by an angle of 90 degrees around a vertical axis by a rotation mechanism (not shown), and division is similarly performed along dividing lines L2 in the other direction that are perpendicular to the one dividing line L1. When the wafer W has been divided along all of the dividing lines L2 in the other direction, the series of division operations for the wafer W is completed, and a plurality of chips are obtained by dividing the wafer W.

[0052] As described above, in the breaking device 1 of this embodiment, the switching control unit 90 switches the dividing method between the two-point support method (first dividing mechanism) shown in Figures 5 and 6 and the three-point support method (second dividing mechanism) shown in Figures 7 and 8 depending on the material of the wafer W to be divided. This eliminates the need to prepare two breaking devices that use different dividing methods, thereby reducing equipment costs and achieving cost reductions, as well as reducing the installation space required for the device.

[0053] In the above embodiment, the modified layer formed inside the wafer W by irradiation with a laser beam is used as the dividing starting point g. However, other methods for forming the dividing starting point g on the wafer W may be used, such as blade dicing, which involves cutting the wafer W along the planned dividing line with a cutting blade to form a bottomed cutting groove (kerf), scribing, which involves forming a groove in the wafer W along the planned dividing line with a diamond cutter blade, or laser scribing, which involves irradiating the surface of the wafer W with a laser beam to form a groove in the wafer W along the planned dividing line.

[0054] In the above embodiments, the wafer is made of a hard material such as SiC or sapphire, but this is not limiting. The wafer may be a silicon wafer. Depending on the wafer material, a two-point support system or a three-point support system may be used.

[0055] In addition, the two-point support method and the three-point support method may be selectively used to divide a single wafer. For example, in the case of rectangular chips, the two-point support method may be selected for dividing one of the two opposing sides, and the three-point support method may be selected for dividing the other two opposing sides.

[0056] Furthermore, the two-point support method and the three-point support method may be used depending on the chip size. For example, if the chip size is relatively large, the two-point support method may be selected, and if the chip size is relatively small, the three-point support method may be selected.

[0057] Furthermore, the present invention is not limited to the application of the above-described embodiments, and it goes without saying that various modifications are possible within the scope of the claims and the technical ideas described in the specification and drawings. [Explanation of symbols]

[0058] 1: braking device, 10: holding table, 11: fixing clamp, 12: Movable clamp, 12a: Movable clamp presser A, 20: Horizontal movement mechanism, 21: slider, 22: guide rail, 23: ball screw, 24: servo motor, 25: nut member, 30: support bar mechanism, 31: first support bar, 32: second support bar, 33: Single support bar lifting mechanism, 34: Support bar interval adjustment mechanism, 40: Support bar rotation mechanism, 41: Rotating shaft, 41a: Recessed portion of rotating shaft, 42: Frame, 43: Driven gear, 44: electric motor, 45: drive gear, 50: support bar lifting mechanism, 51: base, 52: Guide rail, 53: Ball screw, 54: Servo motor, 55: Bearing, 60: support bar horizontal movement mechanism, 70: blade mechanism, 71: first blade, 72: second blade, 73: slider, 74: blade spacing adjustment mechanism, 75: Single blade lifting mechanism, 80: Blade lifting mechanism, 81: Base, 82: Guide rail, 83: Ball screw, 84: Servo motor, 90: Switching control unit, 100: Base, 110: Gate column, D: Device, F: Ring frame, f: protective film, g: dividing point, L1, L2: dividing line, R1, R2: roll, r: guide roller, T: sheet, W: wafer, WS: work set

Claims

1. A breaking device for dividing a wafer, the breaking device dividing the wafer starting from a linear dividing starting point formed on the wafer having a sheet attached to one surface thereof, a first dividing mechanism that sandwiches the wafer from above and below along the dividing starting point and presses the other surface of the wafer at a position a predetermined distance away from the sandwiched position to divide the wafer starting from the dividing starting point; a second dividing mechanism that supports one surface of the wafer at two points on either side of the dividing starting point and presses the dividing starting point from the other surface to divide the wafer starting from the dividing starting point; A braking device comprising:

2. a first support bar and a second support bar for supporting one side of the wafer; a support bar spacing adjustment mechanism that adjusts the spacing between the first support bar and the second support bar; a single support bar lifting mechanism that lifts or lowers either the first support bar or the second support bar; a support bar lifting mechanism that lifts and lowers the single support bar lifting mechanism; a first blade and a second blade that press the other surface of the wafer; a blade spacing adjustment mechanism that adjusts the spacing between the first blade and the second blade; a single-blade lifting mechanism that lifts and lowers either the first blade or the second blade; a blade lifting mechanism that lifts and lowers the single blade lifting mechanism; a switching control unit that switches between the first dividing mechanism and the second dividing mechanism; Equipped with The switching control unit one side of the wafer is supported at one point along the division starting point by either the first support bar or the second support bar, the other side of the wafer is pressed by either the first blade or the second blade facing the first support bar or the second support bar supporting the one side of the wafer to clamp the wafer, and the first blade or the second blade that presses the wafer is controlled to press the other side of the wafer at a position a predetermined distance away from the clamping position, thereby constituting the first dividing mechanism; the first support bar and the second support bar support one surface of the wafer at two points, and either the first blade or the second blade is positioned directly above the dividing starting point and controlled to press the other surface of the wafer, thereby constituting the second dividing mechanism.

2. The braking device according to claim 1.

Images