JP2014170822A - Annular protrusion part removing apparatus and method for processing wafer - Google Patents

Abstract

An adhesive tape is reliably separated from a lower surface of an annular convex portion to satisfactorily remove the annular convex portion of a wafer.
A back surface (103) of a wafer (W) is attached to an adhesive tape (106) stretched on an annular frame (107), and a circular recess (104) and a periphery of the circular recess are formed on the back surface of the wafer. Annular protrusion removing device for removing the annular protrusion from the wafer unit (101) in which the dividing groove (108) is formed leaving the adhesive tape at the boundary between the annular protrusion (105) and the circular recess and the annular protrusion In (1), the scraper member (74) is made to enter the interface between the holding means (22) for holding the wafer unit and the annular convex portion and the adhesive tape, and the annular convex portion is pulled from the adhesive tape starting from the entry location. Scraper means (51) for moving the scraper member along the entire circumference of the wafer while peeling off was used.
[Selection] Figure 4

Description

  The present invention relates to an annular protrusion removing apparatus and a wafer processing method for removing an annular protrusion formed on the outer periphery of a wafer from a wafer.

  In recent years, it has been required to reduce the thickness of a wafer, for example, 50 μm or less, in order to achieve a reduction in weight and size of electrical equipment. Such a thinly formed wafer has a reduced rigidity and is difficult to handle due to warpage, and may be damaged during transportation. Therefore, a grinding method is proposed to reinforce the wafer by grinding only the back surface corresponding to the device area where the device of the wafer is formed, leaving an annular protrusion on the back surface corresponding to the outer peripheral surplus area surrounding the device area. (For example, refer to Patent Document 1).

  There has been proposed a method of removing the annular protrusion from the wafer before dicing the wafer on which the annular protrusion is formed (see, for example, Patent Document 2). In the method described in Patent Document 2, a dividing groove is formed between a circular concave portion formed by back surface grinding and an annular convex portion surrounding the circular concave portion, leaving a pressure sensitive adhesive tape attached to the back surface of the wafer. The concave portion and the annular convex portion are divided. A plurality of claws are inserted into the interface between the annular convex portion and the adhesive tape from the outer peripheral side of the wafer, and the plural convex portions are removed from the wafer by pulling up the plural claws.

JP 2007-173487 A JP 2011-061137 A

  However, in the method described in Patent Document 2, when the adhesiveness is strong, such as when the adhesive area of the wafer is large or the uneven state of the back surface of the wafer is intense, the interface between the annular convex part and the adhesive tape is used. It was difficult to completely separate the adhesive tape from the lower surface of the annular convex portion because the nail did not fully enter.

  The present invention has been made in view of such points, and an annular convex removing device capable of reliably separating the adhesive tape from the lower surface of the annular convex portion to satisfactorily remove the annular convex portion from the wafer and the processing of the wafer. It aims to provide a method.

  The annular convex portion removing device of the present invention has a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion, and a dividing groove is formed at a boundary portion between the circular concave portion and the annular convex portion. An annular convex removing device that removes the annular convex portion from a wafer unit comprising a wafer, an adhesive tape attached to the back surface of the wafer, and an annular frame to which an outer peripheral portion of the adhesive tape is attached. Holding means for holding the wafer unit, and entering the interface between the annular convex portion and the adhesive tape from the wafer unit held by the holding means, separating the annular convex portion from the adhesive tape, A scraper means for removing the annular convex portion from the wafer unit, and the holding means has a holding surface having a slightly smaller diameter than the circular concave portion, and a chuck table for sucking and holding the circular concave portion; A frame fixing portion that is disposed on the outer peripheral side of the chuck table and fixes the annular frame; and a relative movement portion that relatively moves the chuck table and the frame fixing portion in the vertical direction. Three or more disk-shaped scraper members for entering the interface between the annular convex portion and the adhesive tape and separating the adhesive tape from the lower surface of the annular convex portion, and a plurality of the scraper members simultaneously with the standby position and each other A linearly moving portion that moves between an operating position that approaches the annular convex portion of the wafer and approaches the radial direction, and a plurality of the scraper members positioned at the operating position are simultaneously rotated along the outer periphery of the wafer. A rotating drive unit that moves the plurality of scraper members in a vertical direction and a left-right direction.

  A wafer processing method according to the present invention is a wafer processing method for removing an annular protrusion from a wafer having a circular recess formed on the back surface and an annular protrusion surrounding the circular recess, the back surface of the wafer being A wafer unit forming step of forming a wafer unit by attaching an outer peripheral portion of the adhesive tape to an annular frame, and after the wafer unit forming step, the circular concave portion and the annular convex portion. A dividing groove forming step for forming a dividing groove at the boundary, and after the dividing groove forming step, the circular concave portion of the wafer is placed on the chuck table having a holding surface slightly smaller than the circular concave portion via the adhesive tape. A holding step in which the circular recess is sucked and held by the chuck table and the annular frame is fixed by a frame fixing portion disposed on an outer periphery of the chuck table; After the step, the frame fixing portion and the chuck table are moved relative to each other in the vertical direction to protrude the chuck table with respect to the frame fixing portion, and after the protruding step, a plurality of scraper members are attached to the wafer. After positioning at the interface height between the annular convex part and the adhesive tape from the outer peripheral side of the wafer, the scraper members are moved toward the wafer center direction to enter or enter the interface between the annular convex part and the adhesive tape. And rotating the plurality of scraper members along the outer periphery of the wafer over the entire circumference of the wafer, separating the adhesive tape from the lower surface of the annular convex portion, and after the adhesive tape separating step, The scraper member that has entered the interface is moved away from the wafer held by the chuck table, and the annular convex portion is moved to the wafer. A removal step of removing from the blade unit, characterized by comprising a.

  According to these configurations, three or more scraper members enter the interface between the annular convex portion and the adhesive tape, and each scraper member rotates along the entire circumference of the wafer while peeling the annular convex portion from the adhesive tape. Is done. If three or more scraper members enter the interface between the annular convex part and the adhesive tape, each of the entry points starts as a peeling of the interface, so the annular convex part adheres firmly to the adhesive tape. Even if it does, an annular convex part can be separated from an adhesive tape over the perimeter. Further, since the annular convex portion can be held in a state separated from the adhesive tape, the annular convex portion can be removed by three or more scraper members, and there is no need to provide a removing means separately from the scraper means.

  Another annular convex removing device of the present invention has a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion, and a dividing groove is formed at a boundary portion between the circular concave portion and the annular convex portion. An annular projection removing device for removing the annular projection from a wafer unit comprising a formed wafer, an adhesive tape attached to the back surface of the wafer, and an annular frame to which an outer peripheral portion of the adhesive tape is attached. A holding means for holding the wafer unit; and the wafer unit held by the holding means enters the interface between the annular convex portion and the adhesive tape and removes the adhesive tape from the lower surface of the annular convex portion. Scraper means for separating, and removal means for holding the annular convex portion separated from the adhesive tape by the scraper means and removing it from the wafer unit. The holding means is formed by the circular concave portion. A chuck table having a holding surface with a slightly smaller diameter and sucking and holding the circular recess, a frame fixing portion disposed on the outer peripheral side of the chuck table and fixing the annular frame, the chuck table and the frame fixing portion And a relative moving part for relatively moving in the vertical direction, and the scraper means enters the interface between the annular convex part and the adhesive tape and separates the adhesive tape from the lower surface of the annular convex part. A disk-shaped scraper member, a linearly moving portion that moves the scraper member between a standby position and an operating position that acts radially on the annular convex portion of the wafer and is positioned at the operating position. A rotation drive unit that rotates the scraper member along the outer periphery of the wafer, and the removing means is separated from the adhesive tape by the scraper means. A holding portion for holding the annular convex portion, characterized in that it and a vertical moving unit that moves from the pressure-sensitive adhesive tape to lift the holding portion to the outside.

  Another wafer processing method of the present invention is a wafer processing method for removing an annular convex portion from a wafer having a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion. A wafer unit forming step in which an adhesive tape is attached to the back surface of the substrate and an outer peripheral portion of the adhesive tape is attached to an annular frame to form a wafer unit, and after the wafer unit forming step, the circular concave portion and the annular convex portion A dividing groove forming step for forming a dividing groove at the boundary between the first and second portions, and after the dividing groove forming step, the circular concave portion of the wafer is mounted on the chuck table having a holding surface slightly smaller than the circular concave portion via the adhesive tape. Holding the circular recess with the chuck table, and holding the annular frame with a frame fixing portion disposed on the outer periphery of the chuck table; After the holding step, the frame fixing portion and the chuck table are moved relative to each other in the vertical direction to protrude the chuck table with respect to the frame fixing portion. After the protruding step, the scraper member is attached to the wafer. After positioning at the interface height between the annular convex portion and the adhesive tape from the outer peripheral side, the scraper member is moved toward the wafer center to enter the interface between the annular convex portion and the adhesive tape, and along the outer periphery of the wafer. The scraper member is rotated over the entire circumference of the wafer to separate the adhesive tape from the lower surface of the annular convex portion, and after the adhesive tape separating step, the annular convex portion is held by a removing means, And a removal step of removing from the wafer unit.

  According to these configurations, the scraper member enters the interface between the annular convex portion and the adhesive tape, and the scraper member is rotated along the entire circumference of the wafer while peeling the annular convex portion from the adhesive tape. If the scraper member enters the interface between the annular convex portion and the adhesive tape, the separation of the interface progresses starting from this entry point, so even if the annular convex portion is firmly adhered to the adhesive tape, The annular convex portion can be separated from the adhesive tape over the circumference. Therefore, the annular protrusion can be satisfactorily removed from the wafer unit by the removing means.

  According to the present invention, the adhesive tape is reliably separated from the lower surface of the annular convex portion by rotating the scraper member over the entire circumference of the wafer in a state where the scraper member enters the interface between the annular convex portion and the adhesive tape. Thus, the annular protrusion can be satisfactorily removed from the wafer.

It is a perspective view of the cyclic | annular convex part removal apparatus which concerns on 1st Embodiment. It is a perspective view of the scraper means which concerns on 1st Embodiment. It is explanatory drawing of the processing method of the wafer which concerns on 1st Embodiment. It is explanatory drawing of the processing method of the wafer which concerns on 1st Embodiment. It is a perspective view of the scraper means which concerns on 2nd Embodiment. It is explanatory drawing of the processing method of the wafer which concerns on 2nd Embodiment.

  Hereinafter, with reference to the accompanying drawings, a description will be given of an annular convex portion removing apparatus according to a first embodiment. FIG. 1 is a perspective view of an annular convex portion removing apparatus according to the first embodiment. In addition, the cyclic | annular convex part removal apparatus which concerns on 1st Embodiment is not limited to the structure shown in FIG. 1, It can change suitably. The annular convex part removal apparatus should just have the structure which isolate | separates the interface of an annular convex part and an adhesive tape by rotating a scraper member. In FIG. 1, for convenience of explanation, the housing that covers the upper part of the apparatus is omitted.

  As shown in FIG. 1, the annular convex removing device 1 is configured to remove the reinforcing annular convex 105 formed on the outer periphery of the wafer W from the wafer unit 101 on the chuck table 23. The wafer W is formed in a substantially disk shape, and is divided into a plurality of regions by lattice-shaped division planned lines (not shown) arranged on the surface 102. At the center of the wafer W, various devices such as ICs and LSIs are formed in each region partitioned by the division lines. The surface 102 of the wafer W is divided into a device region A1 where a plurality of devices are formed and an outer peripheral surplus region A2 surrounding the device region A1 (see FIG. 3A).

  On the back surface 103 of the wafer W, a circular concave portion 104 is formed in a region corresponding to the device region A1, and an annular convex portion 105 is formed in a region corresponding to the outer peripheral surplus region A2 (see FIG. 3A). As described above, only the central portion of the wafer W is thinned by the circular concave portion 104, and the rigidity of the wafer W is enhanced by the annular convex portion 105 surrounding the circular concave portion 104. An ultraviolet curable adhesive tape 106 is attached to the back surface 103 of the wafer W, and an annular frame 107 is attached to the outer periphery of the adhesive tape 106. The wafer W is supported on the annular frame 107 via the adhesive tape 106 and is conveyed as the wafer unit 101.

  In the wafer unit 101, a dividing groove 108 is formed at a boundary portion between the circular concave portion 104 and the annular convex portion 105 (see FIG. 3D). The dividing groove 108 divides the circular concave portion 104 and the annular convex portion 105 while leaving the adhesive tape 106 attached to the back surface 103 of the wafer W, and the cutting device before being carried into the annular convex portion removing apparatus 1. (Not shown). The wafer W may be a semiconductor wafer such as silicon or GaAs, or a ceramic, glass, sapphire inorganic material substrate, a ductile material of a plate metal or a resin, and a flatness of micron order to submicron order is required. Various processing materials may be used.

  The annular convex removing device 1 includes a mounting table 11 on which a cassette (not shown) is mounted, a separation table 21 on which a wafer unit 101 is held when the annular convex 105 is separated from the adhesive tape 106, and a wafer unit. The storage base 31 that stores the annular convex portion 105 separated from the base 101 is arranged side by side. A box-shaped ultraviolet irradiation unit 12 is provided on the upper surface of the mounting table 11, and the upper surface of the ultraviolet irradiation unit 12 is a mounting surface 13 of the cassette. Inside the mounting table 11, an elevator mechanism is provided below the ultraviolet irradiation unit 12. As the cassette is moved up and down together with the ultraviolet irradiation unit 12 by the elevator mechanism, the drawing position and pushing position of the wafer unit 101 are adjusted in the height direction.

  A holding unit 22 that holds the wafer unit 101 is provided on the separation table 21. The holding unit 22 includes a chuck table 23 that holds the wafer W by suction and a frame fixing unit 24 that fixes the annular frame 107 on the outer peripheral side of the chuck table 23. A holding surface 25 is formed on the upper surface of the chuck table 23 by a porous ceramic material. The holding surface 25 is formed to have a slightly smaller diameter than the circular recess 104 of the wafer W (see FIG. 3D). For this reason, the holding surface 25 enters inside the circular recess 104, and the holding surface 25 is covered with the wafer W. Then, the wafer W is sucked and held via the adhesive tape 106 by the negative pressure generated on the holding surface 25.

  Fixing surfaces 26 are formed by electromagnets at four positions on the upper surface of the frame fixing portion 24. The annular frame 107 made of a magnetic material is attracted and fixed by the magnetic force generated on each fixing surface 26. In addition, a relative movement unit (not shown) that relatively moves the chuck table 23 and the frame fixing unit 24 in the vertical direction is provided in the separation table 21. The relative movement part is comprised by the air cylinder, for example. In the holding unit 22, the wafer W is protruded above the annular frame 107 by being lowered while the annular frame 107 is fixed to the frame fixing portion 24.

  The separation table 21 is provided with a centering guide 27 for guiding the wafer unit 101 above the chuck table 23. The centering guide 27 guides the wafer unit 101 close to each other when the wafer unit 101 is put in and out, and performs centering of the wafer unit 101 with respect to the chuck table 23. Further, the centering guides 27 are separated from each other so that the upper portion of the holding means 22 is opened when the wafer unit 101 is not taken in and out.

  An accommodation case 32 is formed in the upper portion of the accommodation table 31 in which the annular convex portion 105 (see FIG. 4C) separated from the wafer unit 101 is discarded. The upper surface of the housing case 32 is opened, and the annular convex portion 105 is discarded from above by the scraper means 51 described later. On the front surface of the storage case 32, an opening / closing door 33 is provided that can take out the annular protrusion 105 from the storage case 32. A push-pull mechanism 41 for inserting / removing the wafer unit 101 to / from the cassette and an annular convex portion 105 from the wafer unit 101 on the separation table 21 are removed from the mounting table 11, the separation table 21, and the inner wall surface 36 of the storage table 31. Scraper means 51 is provided.

  In the push-pull mechanism 41, a push-pull arm 43 is cantilevered by a ball screw type Y-axis moving means 42 extending in the left-right direction. The base end portion of the push-pull arm 43 is slidably supported on the pair of guide rails 44 of the Y-axis moving unit 42. A nut portion is provided on the back side of the base end portion of the push-pull arm 43, and a ball screw 45 is screwed into the nut portion. The push-pull arm 43 is moved in the left-right direction when the ball screw 45 is rotationally driven by a drive motor 46 connected to one end of the ball screw 45.

  The scraper means 51 is configured to separate the adhesive tape 106 from the lower surface of the annular convex portion 105 of the wafer W by using four disc-shaped scraper members 74 (see FIG. 4B). The scraper means 51 has an up-and-down moving part 52 that moves each scraper member 74 in the vertical direction and the left-right direction. The up-and-down moving unit 52 includes a ball screw type Y-axis moving unit 53 extending in the left-right direction and a ball screw type Z-axis moving unit 54 extending in the vertical direction. A pair of guide rails 55 of the Y-axis moving unit 53 supports a slider 56 of the Z-axis moving unit 54 so as to be slidable.

  A pair of guide rails 57 on the slider 56 slidably supports the base end portion of the arm 63, and four scraper members 74 are disposed on the distal end side of the arm 63 via a substantially cross-shaped support portion 64. Is supported. A nut portion is provided on the back side of the slider 56 of the Z-axis moving means 54, and a ball screw 58 of the Y-axis moving means 53 is screwed to the nut portion. A nut portion is provided on the back side of the base end portion of the arm 63, and a ball screw 59 of the Z-axis moving means 54 is screwed to the nut portion. When the ball screws 58 and 59 are rotationally driven by drive motors 61 and 62 connected to one end portions of the ball screws 58 and 59, the scraper member 74 is moved in the left-right direction and the vertical direction.

  The scraper means 51 inserts each scraper member 74 into the interface between the annular convex portion 105 and the adhesive tape 106 and moves the scraper member 74 along the outer periphery of the wafer W while peeling the annular convex portion 105 from the adhesive tape 106 ( (See FIG. 4B). Thereby, the annular convex part 105 is isolate | separated from the surface of the adhesive tape 106 over a perimeter. Further, the scraper means 51 can hold the annular convex portion 105 separated from the adhesive tape 106 by using four scraper members 74 and transport it toward the storage table 31. The details of the scraper means 51 will be described later.

  In the annular convex portion removal apparatus 1 configured as described above, the wafer unit 101 is transported to the ultraviolet irradiation unit 12, and ultraviolet rays are irradiated only on a predetermined portion of the adhesive tape 106 corresponding to the annular convex portion 105 (FIG. 3C). reference). Next, the wafer unit 101 is conveyed to the separation table 21, and the annular convex portion 105 is separated from the adhesive tape 106 by the scraper means 51 (see FIG. 4B). And the annular convex part 105 is conveyed by the scraper means 51 to the storage stand 31, and the annular convex part 105 is discarded from the scraper means 51 to the storage case 32 (refer FIG. 4C). In this way, the annular protrusion 105 is removed from the wafer unit 101 (wafer W).

  The detailed configuration of the scraper means will be described with reference to FIG. FIG. 2 is a perspective view of the scraper means according to the first embodiment. The scraper means may be configured in any way as long as the annular convex portion can be separated from the adhesive tape by a plurality of scraper members. In FIG. 2, for convenience of explanation, the configuration of the base end side of the arm of the scraper member is omitted.

  As shown in FIG. 2, the support portion 64 of the scraper means 51 is formed in a substantially cross shape by a cylindrical base portion 65 and a long guide base 66 extending in four directions from the base portion 65. A linear motion drive unit 67 is provided on the base end side of each guide base 66, and one end portion of a ball screw 69 is connected thereto. Further, a support wall 68 is provided on the front end side of each guide base 66 so as to face the linear motion drive portion 67, and the other end portion of the ball screw 69 is supported. An inner nut 71 is screwed into each ball screw 69. A disc-shaped scraper member 74 is rotatably provided below the inner nut 71 via a bearing 72.

  The tip portion of the scraper member 74 protrudes outward from the outer periphery of the bearing 72 and is formed in a single-edged shape having an inclined upper surface. The protruding length of the tip portion of the scraper member 74 is larger than the width dimension of the annular protrusion 105, and the annular protrusion 105 can be reliably separated from the adhesive tape 106. Each scraper member 74 is moved between a standby position away from the annular convex portion 105 and an operating position acting on the annular convex portion 105 by driving each inner nut 71 by each linear motion drive portion 67. For this reason, the scraper members 74 are spaced apart and approached in the radial direction with the annular protrusion 105 (wafer W) interposed therebetween. Further, the base portion 65 is provided at the tip of the arm 63 via the rotation drive portion 73.

  In the scraper means 51 configured in this way, a plurality of scraper members 74 are approached and inserted into the interface between the annular convex portion 105 and the adhesive tape 106, and the base portion 65 is rotated to rotate the annular convex from the adhesive tape 106. The part 105 is separated over the entire circumference (see FIG. 4B). At this time, since the scraper member 74 is fixed to the bearing 72, the scraper member 74 is rotated along with the movement of the scraper member 74 along the annular convex portion 105. Therefore, when the scraper member 74 advances through the interface between the annular convex portion 105 and the adhesive tape 106, the resistance acting on the cutting edge of the scraper member 74 is reduced.

  When the annular protrusion 105 is separated from the adhesive tape 106, the lower surface of the annular protrusion 105 is supported on the upper surfaces of the plurality of scraper members 74. That is, the scraper means 51 according to the present embodiment also functions as an edge clamp type hand that holds the annular convex portion 105 with a plurality of scraper members 74.

  With reference to FIG.3 and FIG.4, the processing method which removes an annular convex part from a wafer unit is demonstrated. 3 and 4 are explanatory diagrams of the wafer processing method according to the first embodiment. The wafer processing methods shown in FIGS. 3 and 4 are merely examples, and can be changed as appropriate.

  As shown in FIG. 3A, a wafer unit forming process is first performed. In the wafer unit forming step, an ultraviolet curable adhesive tape 106 is attached to the back surface 103 of the wafer W, and an annular frame 107 is attached to the outer periphery of the adhesive tape 106 to form the wafer unit 101. In this case, the adhesive tape 106 is adhered following the surface shapes of the circular concave portion 104 and the annular convex portion 105 of the wafer W. The wafer unit 101 is carried into a cutting device (not shown).

  As shown in FIG. 3B, a dividing groove forming step is performed after the wafer unit forming step. In the dividing groove forming step, the dividing groove 108 is formed at the boundary between the circular concave portion 104 and the annular convex portion 105 by circle cutting with the cutting blade 76. In this case, the upper surface of the chuck table 77 of the cutting apparatus is formed in a step shape following the shape of the back surface of the wafer W. On the upper stage of the chuck table 77, a holding surface 78 is formed of a porous ceramic material. When the wafer W is placed on the chuck table 77, the circular recess 104 of the wafer W is sucked and held on the holding surface 78 of the chuck table 77 via the adhesive tape 106.

  At this time, the annular frame 107 of the wafer unit 101 is clamped and held by the clamp 79 around the chuck table 77. Further, the cutting blade 76 is positioned at the boundary between the circular concave portion 104 and the annular convex portion 105 so as to form the dividing groove 108. Then, cutting water is sprayed from a spray nozzle (not shown), the cutting blade 76 is rotated at a high speed, and the wafer W is cut by the cutting blade 76. In this case, the cutting depth is adjusted so as to cut halfway through the adhesive tape 106. Subsequently, when the chuck table 77 rotates, an annular dividing groove 108 is formed between the circular concave portion 104 and the annular convex portion 105 along the outer periphery of the wafer W. The processed wafer unit 101 is carried into the annular convex portion removing apparatus 1.

  The dividing groove forming step is not limited to the circle cutting by the cutting blade 76. The dividing groove forming step only needs to have a structure in which the dividing groove 108 is formed between the circular concave portion 104 and the annular convex portion 105 of the wafer W. For example, a laser beam having a wavelength that absorbs the wafer W is used. May be performed by conventional ablation. Ablation means that when the irradiation intensity of the laser beam exceeds a predetermined processing threshold, it is converted into electronic, thermal, photochemical and mechanical energy on the solid surface, resulting in neutral atoms, molecules, positive and negative ions, A phenomenon in which radicals, clusters, electrons, and light are explosively emitted and the solid surface is etched.

  As shown in FIG. 3C, an ultraviolet irradiation step is performed after the dividing groove forming step. In the ultraviolet irradiation process, the wafer unit 101 is carried into the ultraviolet irradiation unit 12, and ultraviolet rays are irradiated only on predetermined portions of the ultraviolet curable adhesive tape 106 corresponding to the annular convex portion 105. In this case, the inside of the ultraviolet irradiation unit 12 is partitioned vertically by a mask 14, and an annular opening 15 corresponding to the annular convex portion 105 is formed in the mask 14. A wafer unit 101 is accommodated above the mask 14, and an ultraviolet lamp 16 is disposed below the mask 14. When the ultraviolet lamp 16 is turned on, the region corresponding to the annular convex portion 105 of the adhesive tape 106 is irradiated with ultraviolet rays through the annular opening 15, and the adhesive force of the adhesive tape 106 to the annular convex portion 105 is reduced.

  As shown in FIG. 3D, a holding process is performed after the ultraviolet irradiation process. In the holding step, the circular recess 104 of the wafer W is sucked and held by the chuck table 23 and the annular frame 107 is sucked and held by the frame fixing unit 24. In this case, the holding surface 25 of the chuck table 23 is slightly smaller in diameter than the circular recess 104, and the wafer W is held on the holding surface 25 with the holding surface 25 entering the inside of the circular recess 104. An annular frame 107 made of a magnetic material is attracted and fixed to the fixing surface 26 in the frame fixing portion 24.

  As shown to FIG. 4A, a protrusion process is implemented after a holding process. In the projecting step, the frame fixing unit 24 and the chuck table 23 are relatively moved in the vertical direction, and the chuck table 23 is projected from the frame fixing unit 24. In this case, the chuck table 23 is positioned above the frame fixing part 24 by lowering the frame fixing part 24 by a relative moving part (not shown). The protruding amount of the chuck table 23 is adjusted to such an extent that the scraper member 74 does not interfere with the annular frame 107 in the next adhesive tape separating step. Further, instead of lowering the annular frame 107, the chuck table 23 may be raised.

  As shown in FIG. 4B, an adhesive tape separation step is performed after the protruding step. In the adhesive tape separating step, the adhesive tape 106 is separated from the lower surface of the annular convex portion 105 by the four scraper members 74 of the scraper means 51. In this case, the scraper means 51 moves above the chuck table 23, and the scraper member 74 located on the four sides of the scraper means 51 is positioned at the interface height between the annular convex portion 105 and the adhesive tape 106. Further, the scraper members 74 facing each other are separated from each other, and the cutting edge of the scraper member 74 is positioned on the outer side in the radial direction of the wafer W.

  Then, the scraper members 74 approach each other toward the center of the wafer W, and the scraper members 74 are inserted into the interface between the annular convex portion 105 and the adhesive tape 106. At this time, since the adhesive force at the interface between the annular convex portion 105 and the adhesive tape 106 is reduced, the scraper member 74 easily enters the interface. When each scraper member 74 enters the interface between the annular convex portion 105 and the adhesive tape 106, each scraper member 74 is simultaneously rotated along the outer periphery of the wafer W. Thereby, each scraper member 74 is rotated over the entire circumference of the wafer W while peeling the annular convex portion 105 from the adhesive tape 106, and the annular convex portion 105 is reliably separated from the adhesive tape 106.

  Further, when the scraper member 74 moves while peeling the annular convex portion 105, the scraper member 74 itself is also rotated. As a result, since the blade edge of the rotated scraper member 74 moves along the outer periphery of the wafer W while cutting the interface between the annular convex portion 105 and the adhesive tape 106, the resistance applied to the blade edge of the scraper member 74 is reduced.

  In the present embodiment, each scraper member 74 is moved along the outer periphery of the wafer W after the scraper members 74 have entered the interface between the annular convex portion 105 and the adhesive tape 106. It is not limited to. Each scraper member 74 may be moved along the outer periphery of the wafer W while each scraper member 74 enters the interface between the annular convex portion 105 and the adhesive tape 106. Thereby, the resistance applied to the cutting edge of the scraper member 74 can be further reduced.

  As shown in FIG. 4C, the removal step is performed after the adhesive tape separation step. In the removal step, each scraper member 74 that has entered the interface between the annular protrusion 105 and the adhesive tape 106 is moved away from the chuck table 23, and the annular protrusion 105 is removed from the wafer unit 101. In this case, the annular convex portion 105 is stably held from four directions by the four scraper members 74. Further, since the annular convex portion 105 is physically peeled from the adhesive tape 106 over the entire circumference, the annular convex portion 105 is favorably peeled from the adhesive tape 106. The annular protrusion 105 is transported to the storage table 31 (see FIG. 1) by the scraper means 51 and discarded.

  As described above, according to the annular protrusion removing device 1 according to the first embodiment, the four scraper members 74 enter the interface between the annular protrusion 105 and the adhesive tape 106, and the annular protrusion is removed from the adhesive tape 106. The scraper members 74 are simultaneously rotated along the entire circumference of the wafer W while peeling off the portion 105. When each scraper member 74 enters the interface between the annular convex portion 105 and the adhesive tape 106, the separation of the interface progresses starting from each of the entry portions, so that the annular convex portion 105 is firmly attached to the adhesive tape 106. Even if it adheres, the cyclic | annular convex part 105 can be isolate | separated from the adhesive tape 106 over the perimeter. Further, since the annular convex portion 105 can be held in a state separated from the adhesive tape 106, the annular convex portion 105 can be removed by the four scraper members 74, and it is not necessary to provide a removing means separately from the scraper means 51.

  Subsequently, an annular protrusion removing device according to a second embodiment will be described with reference to the accompanying drawings. The annular convex portion removing apparatus according to the second embodiment is different from the annular convex portion removing apparatus according to the first embodiment in that the scraper means has a configuration and a removing means. Therefore, the differences will be mainly described.

  FIG. 5 is a perspective view of the scraper means according to the second embodiment. The scraper means may be configured in any way as long as the annular convex portion can be separated from the adhesive tape by a single scraper member. In FIG. 5, for convenience of explanation, the configuration of the base end side of the arm of the scraper member is omitted.

  As shown in FIG. 5, the scraper means 81 is provided with a long guide base 86 extending from a cylindrical base portion 85 to one side. A linear drive portion 87 is provided on the proximal end side of the guide base 86, and one end portion of the ball screw 89 is connected thereto. Further, a support wall 88 is provided on the front end side of the guide base 86 so as to face the linear motion drive portion 87, and the other end portion of the ball screw 89 is supported. An inner nut 91 is screwed onto the ball screw 89, and a disk-shaped scraper member 94 is provided below the inner nut 91 via a bearing 92. Further, the base portion 85 is provided at the tip of the arm 82 via the rotation drive portion 93.

  As described above, the scraper unit 81 according to the second embodiment has a standby position where the single scraper member 94 is separated from the annular convex portion 105 (see FIG. 6A) and an operating position which acts on the annular convex portion 105. It differs from the scraper means 51 which concerns on 1st Embodiment by the point moved between.

  With reference to FIG. 6, the processing method which removes an annular convex part from a wafer unit is demonstrated. FIG. 6 is an explanatory diagram of a wafer processing method according to the second embodiment. The wafer unit forming process, the dividing groove forming process, the ultraviolet irradiation process, the holding process, and the protruding process of the wafer processing method according to the second embodiment are the same as those in the first embodiment. Therefore, only the adhesive tape separation step and the removal step will be described here.

  As shown in FIG. 6A, the adhesive tape separating step is performed after the wafer unit forming step, the dividing groove forming step, the ultraviolet irradiation step, the holding step, and the protruding step are performed as in the first embodiment. In the adhesive tape separating step, the adhesive tape 106 is separated from the lower surface of the annular convex portion 105 by the single scraper member 94 of the scraper means 81. In this case, the scraper means 81 moves above the chuck table 23, and the single scraper member 94 is positioned at the interface height between the annular convex portion 105 and the adhesive tape 106. The cutting edge of the scraper member 94 is positioned on the radially outer side of the wafer W.

  Then, the scraper member 94 is moved toward the center of the wafer W, and the scraper member 94 is inserted into the interface between the annular convex portion 105 and the adhesive tape 106. When the scraper member 94 enters the interface between the annular convex portion 105 and the adhesive tape 106, the scraper member 94 is rotated along the entire outer periphery of the wafer W. Thereby, the scraper member 94 moves while peeling the annular convex portion 105 from the adhesive tape 106, and the annular convex portion 105 is reliably separated from the adhesive tape 106. As in the first embodiment, the resistance applied to the cutting edge of the scraper member 94 is reduced by separating the annular convex portion 105 from the adhesive tape 106 while the scraper member 94 rotates. Thereafter, the scraper means 81 is retracted from above the chuck table 23 with the annular convex portion 105 remaining on the adhesive tape 106.

  As shown to FIG. 6B, a removal process is implemented after an adhesive tape separation process. In the removing step, the annular convex portion 105 is held by the removing means 96 and the annular convex portion 105 is removed from the wafer unit 101. In this case, the removing means 96 has a holding portion 97 that holds the annular convex portion 105, and an up-and-down moving portion (not shown) that moves the holding portion 97 up and down and moves the holding portion 97 from the adhesive tape 106 to the outside. doing. The annular convex portion 105 separated from the adhesive tape 106 is sucked and held by the suction pad 98 of the holding portion 97, and is transported to the receiving table 31 (see FIG. 1) and discarded.

  As described above, according to the annular convex portion removing apparatus 1 according to the second embodiment, the scraper member 94 enters the interface between the annular convex portion 105 and the adhesive tape 106, and the annular convex portion 105 extends from the adhesive tape 106. , The scraper member 94 is rotated along the entire circumference of the wafer W. When the scraper member 94 enters the interface between the annular convex portion 105 and the adhesive tape 106, the separation of the interface progresses starting from this entry location, so the annular convex portion 105 is firmly adhered to the adhesive tape 106. However, the annular convex portion 105 can be separated from the adhesive tape 106 over the entire circumference. Therefore, the annular protrusion 105 can be satisfactorily removed from the wafer unit 101 by the removing means 96.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  For example, in the first and second embodiments described above, the scraper members 74 and 94 are rotatably supported by the bearings 72 and 92. However, the present invention is not limited to this configuration. The scraper members 74 and 94 may be supported by a rotary motor so as to be driven to rotate. Further, the scraper members 74 and 94 may be directly fixed to the inner nuts 71 and 91 so as not to rotate. Even with such a configuration, the adhesive tape 106 can be separated from the lower surface of the annular convex portion 105.

  In the first and second embodiments described above, the scraper members 74 and 94 are moved along the outer periphery of the wafer W. However, the present invention is not limited to the configuration in which the outer periphery of the wafer W is rotated once. The scraper members 74 and 94 may be configured to circulate around the outer periphery of the wafer W until the adhesive tape 106 is reliably separated from the lower surface of the annular convex portion 105.

  In the first and second embodiments described above, the ultraviolet irradiation process is performed. However, the present invention is not limited to this configuration. If the adhesive tape 106 can be separated from the lower surface of the annular convex portion 105 in the adhesive tape separating step, the ultraviolet irradiation step can be omitted.

  In the first and second embodiments described above, the frame fixing portion 24 is configured to attract and fix the annular frame 107 with an electromagnet. However, the present invention is not limited to this configuration. The frame fixing unit 24 may be configured to clamp and fix the annular frame 107, for example, as long as the annular frame 107 can be fixed.

  In the first embodiment described above, the scraper means 51 includes the four scraper members 74. However, the present invention is not limited to this configuration. In the first embodiment, the scraper means 51 may be configured to have three or more scraper members 74.

  As described above, the present invention has an effect that the annular protrusion can be reliably removed from the wafer unit by reliably separating the annular protrusion from the adhesive tape, and in particular, the annular protrusion of a large diameter wafer is removed. This is useful for an annular protrusion removing apparatus and a wafer processing method.

DESCRIPTION OF SYMBOLS 1 Annular convex part removal apparatus 22 Holding means 23 Chuck table 24 Frame fixing | fixed part 51,81 Scraper means 52 Lifting / moving part 67,87 Direct drive part 73,93 Rotation drive part 74,94 Wafer unit 102 Wafer surface 103 Wafer back surface 104 Circular concave portion 105 Annular convex portion 106 Adhesive tape 107 Annular frame 108 Dividing groove

Claims (4)

A wafer having a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion, and a dividing groove formed at a boundary portion between the circular concave portion and the circular convex portion, and attached to the back surface of the wafer An annular convex part removing device for removing the annular convex part from a wafer unit comprising an adhesive tape and an annular frame to which an outer peripheral part of the adhesive tape is attached,
A holding means for holding the wafer unit; and the wafer unit held by the holding means enters the interface between the annular convex portion and the adhesive tape to separate the annular convex portion from the adhesive tape; Scraper means for removing the annular projection from the unit, and
The holding means has a holding surface having a slightly smaller diameter than the circular recess and sucks and holds the circular recess, and a frame fixing portion disposed on the outer peripheral side of the chuck table and fixing the annular frame. A relative movement part for relatively moving the chuck table and the frame fixing part in the vertical direction,
The scraper means includes three or more disk-shaped scraper members for entering the interface between the annular convex portion and the adhesive tape and separating the adhesive tape from the lower surface of the annular convex portion, and a plurality of the scraper members A linear motion moving portion that simultaneously moves between a standby position and an operating position that acts radially on the annular convex portion of the wafer and a plurality of the scraper members positioned at the operating position at the same time A rotation drive unit that rotates along the outer periphery of the, a lifting and lowering movement unit that moves the plurality of scraper members in the vertical direction and the left-right direction,
An annular convex portion removing device comprising: A wafer processing method of removing the annular convex portion from a wafer having a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion,
A wafer unit forming step in which an adhesive tape is attached to the back surface of the wafer, and an outer peripheral portion of the adhesive tape is attached to an annular frame to form a wafer unit;
After the wafer unit forming step, a dividing groove forming step for forming a dividing groove at the boundary between the circular concave portion and the annular convex portion,
After the dividing groove forming step, the circular recess of the wafer is placed on the chuck table having a holding surface slightly smaller than the circular recess through the adhesive tape, and the circular recess is sucked and held by the chuck table. A holding step of fixing the annular frame with a frame fixing portion disposed on the outer periphery of the chuck table;
After the holding step, a projecting step of projecting the chuck table relative to the frame fixing portion by relatively moving the frame fixing portion and the chuck table in the vertical direction;
After the projecting step, the plurality of scraper members are positioned at the interface height between the annular convex portion and the adhesive tape from the outer peripheral side of the wafer, and then the plurality of scraper members are moved toward the wafer center to thereby form the annular convex portion. And separating the adhesive tape from the lower surface of the annular convex portion by rotating the plurality of scraper members along the outer periphery of the wafer along the outer periphery of the wafer while entering the interface between the adhesive tape and the adhesive tape. Process,
After the adhesive tape separation step, the scraper member that has entered the interface is moved away from the wafer held by the chuck table, and the annular protrusion is removed from the wafer unit; and
A wafer processing method characterized by comprising: A wafer having a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion, and a dividing groove formed at a boundary portion between the circular concave portion and the circular convex portion, and attached to the back surface of the wafer An annular convex part removing device for removing the annular convex part from a wafer unit comprising an adhesive tape and an annular frame to which an outer peripheral part of the adhesive tape is attached,
Holding means for holding the wafer unit, and scraper means for entering the interface between the annular convex portion and the adhesive tape from the wafer unit held by the holding means and separating the adhesive tape from the lower surface of the annular convex portion And removing means for holding the annular convex portion separated from the adhesive tape by the scraper means and removing it from the wafer unit,
The holding means has a holding surface having a slightly smaller diameter than the circular recess and sucks and holds the circular recess, and a frame fixing portion disposed on the outer peripheral side of the chuck table and fixing the annular frame. A relative movement part for relatively moving the chuck table and the frame fixing part in the vertical direction,
The scraper means includes a disc-shaped scraper member for entering the interface between the annular convex portion and the adhesive tape and separating the adhesive tape from the lower surface of the annular convex portion, and the scraper member as a standby position and a radial direction. A linear motion moving part that moves between the operation position that acts on the annular convex part of the wafer and a rotation drive part that rotates the scraper member positioned at the operation position along the outer periphery of the wafer; Comprising at least
The removing means includes a holding part that holds the annular convex part separated from the adhesive tape by the scraper means, and an up-and-down moving part that moves the holding part up and down and moves the adhesive tape from the top to the outside.
An annular convex portion removing device comprising: A wafer processing method of removing the annular convex portion from a wafer having a circular concave portion formed on the back surface and an annular convex portion surrounding the circular concave portion,
A wafer unit forming step in which an adhesive tape is attached to the back surface of the wafer, and an outer peripheral portion of the adhesive tape is attached to an annular frame to form a wafer unit;
After the wafer unit forming step, a dividing groove forming step for forming a dividing groove at the boundary between the circular concave portion and the annular convex portion,
After the dividing groove forming step, the circular recess of the wafer is placed on the chuck table having a holding surface slightly smaller than the circular recess through the adhesive tape, and the circular recess is sucked and held by the chuck table. A holding step of fixing the annular frame with a frame fixing portion disposed on the outer periphery of the chuck table;
After the holding step, a projecting step of projecting the chuck table relative to the frame fixing portion by relatively moving the frame fixing portion and the chuck table in the vertical direction;
After the projecting step, the scraper member is positioned at the interface height between the annular convex portion and the adhesive tape from the outer peripheral side of the wafer, and then the scraper member is moved toward the center of the wafer to form the annular convex portion and the adhesive tape. An adhesive tape separating step of separating the adhesive tape from the lower surface of the annular convex portion by entering the interface of the wafer and rotating the scraper member along the outer periphery of the wafer over the entire circumference of the wafer;
After the adhesive tape separating step, a removing step of removing the wafer from the wafer unit by holding the annular convex portion by a removing means;
A wafer processing method characterized by comprising:

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