JP2016159412A - Grinding method for package substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a chuck to securely suck and hold a plate-like work without exchanging chuck tables in accordance with kinds of plate-like works.SOLUTION: Since this invention comprises a placement step for placing a package substrate 1 on the holding face 140 of a chuck table 14, a holding face sealing step for covering the outer peripheral edge 3c of an electrode plate 3 with a sheet 5 having an opening 5a smaller than the electrode plate 3 and larger than a resin sealing layer 2 so that the resin sealing layer 2 may be exposed, and a holding step for making the holding face 140 of the chuck table 14 suck and hold the sheet 5 and the package substrate 1, a plate-like work can securely be sucked and held by the exchanging chuck tables 14 without exchanging the chuck tables 14 in accordance with kinds of plate-like works.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a method for grinding a package substrate held on a chuck table.

  A package substrate in which a plurality of package devices are sealed with a resin is thinned to a desired thickness, for example, by grinding the sealing resin of the package substrate in a grinding apparatus. When grinding a package substrate, a dedicated chuck table for sucking and holding the package substrate is required. For example, in a grinding apparatus shown in Patent Document 1 below, a chuck table including a rectangular suction holding portion that sucks and holds a rectangular package substrate is mounted.

  In such a grinding device, the chuck table used differs between grinding a package substrate and grinding a disc-shaped silicon wafer, so depending on the type of plate workpiece to be ground. The chuck table is changed as appropriate.

JP 2014-024136 A

  However, as described above, if the chuck table is replaced according to the type of plate workpiece, the height of the holding surface of the chuck table changes. Therefore, each time the chuck table is replaced, the height position of the holding surface is changed. The adjustment work is troublesome.

  Further, since the package substrate has a portion molded with a sealing resin and an unmolded portion, the outer periphery of the package substrate may be warped. In this case, the outer periphery and the chuck table The suction force leaks from between the holding surface. Therefore, in order to suck and hold the plate-shaped workpiece on which the warp is formed by the holding surface of the chuck table, it is necessary to press the plate-shaped workpiece downward toward the holding surface. On the other hand, even for a plate-shaped workpiece without warping, the suction force may leak between the substrate and the holding surface of the chuck table, and the package substrate may not be sucked and held.

  The present invention has been made in view of the above circumstances, and an object thereof is to ensure that a plate-like workpiece can be sucked and held by the chuck table without changing the chuck table according to the type of the plate-like workpiece. It is said.

  The present invention provides an electrode plate having a plurality of division lines formed on the front surface, a device is formed on the back surface of each region partitioned by the division lines, and a portion of the electrode plate is exposed on the outer peripheral side. A package substrate grinding method comprising grinding a sealing resin layer of a package substrate having a warp to a desired thickness, the device comprising: a sealing resin layer coated with a resin; And a holding surface that covers the outer peripheral side of the electrode plate so that the sealing resin layer is exposed by a sheet having an opening smaller than the electrode plate and larger than the sealing resin layer. The package substrate is ground by a sealing step, a holding step for sucking and holding the sheet and the package substrate on the chuck table, and grinding the sealing resin layer by a grinding means provided with a grindstone. To a thickness finishing comprises a grinding step of thinning, the.

  The present invention is a sheet jig used for the grinding method, a ring, and a sheet attached to the ring and having an opening smaller than the electrode plate of the package substrate and larger than the sealing resin layer. It consists of

  A plate-like member having a thickness equivalent to that of the electrode plate and at least an opening having a size equivalent to that of the electrode plate is attached to the surface of the sheet facing the chuck table. It is preferable.

  The present invention is a sheet jig used in the above grinding method, having at least an outer diameter equal to the outer diameter of the holding surface of the chuck table and having a thickness equivalent to the electrode plate, at least the electrode plate A plate-like member having an opening of the same size as the sheet, and a sheet attached to the plate-like member and having an opening that is smaller than the electrode plate and larger than the sealing resin layer.

  The present invention is a sheet jig used in the above grinding method, and has at least an outer diameter equal to the outer diameter of the holding surface of the chuck table, and is thicker than the electrode plate and thinner than the finished thickness of the package substrate. A plate-shaped member having an opening at the center, the opening being smaller than the electrode plate and larger than the sealing resin layer, and the small opening. A large opening having a thickness substantially equal to that of the electrode plate and having a thickness equivalent to that of the electrode plate. The inner periphery of the opening is between the small opening and the large opening. A step is formed.

  The method for grinding a package substrate according to the present invention includes: a step of placing a package substrate on a holding surface of a chuck table; and a sheet having an opening that is smaller than an electrode plate and larger than a sealing resin layer. Holding surface sealing step for covering the outer peripheral side of the electrode plate so that the resin layer is exposed, holding step for sucking and holding the sheet and the package substrate by the holding surface of the chuck table, and grinding for thinning the package substrate to the finished thickness Therefore, there is no need to change the chuck table itself according to the type of plate workpiece to be ground, and the height of the holding surface does not change. Therefore, for example, a rectangular plate-like workpiece or a disk-like plate-like workpiece can be sucked and held using the same chuck table.

  A sheet jig used in the grinding method is composed of a ring and a sheet attached to the ring and having an opening smaller than the electrode plate of the package substrate and larger than the sealing resin layer. Since the electrode plate and the sheet are sucked by the holding surface of the chuck table with only the sealing resin layer exposed from the opening of the sheet, the inner peripheral portion of the sheet presses the outer peripheral edge of the electrode plate. As a result, the suction force can be prevented from leaking from the holding surface, and the package substrate can be reliably sucked and held by the chuck table.

  A sheet jig used in the grinding method has a thickness equivalent to that of an electrode plate on the surface of the sheet facing the chuck table, and at least an opening having a size equal to that of the electrode plate. By adhering the sheet-like member, the sheet, the plate-like member and the electrode plate are sucked by the holding surface of the chuck table in a state where only the sealing resin layer is exposed from the opening of the sheet. By sucking the shaped member, the sheet can be pulled in the same direction to press the outer peripheral edge of the electrode plate. Therefore, the warping of the electrode plate can be effectively corrected and the package substrate can be more securely sucked and held by the chuck table.

  The sheet jig used in the grinding method has at least an outer diameter equivalent to the outer diameter of the holding surface of the chuck table and has a thickness equivalent to the electrode plate, and at least as large as the electrode plate. A sheet-like member having an opening, and a sheet adhered to the plate-like member and having an opening that is smaller than the electrode plate and larger than the sealing resin layer. There is no need to stick and use, and the sheet jig can be easily placed on the holding surface of the chuck table. Further, since no ring frame is required, there is no need to place the ring frame on the ring frame holding portion.

  A sheet jig used in the grinding method has at least an outer diameter equal to the outer diameter of the holding surface of the chuck table, and is a plate-like member formed thicker than the electrode plate and thinner than the finished thickness of the package substrate. A small opening formed smaller than the electrode plate and larger than the sealing resin layer, and larger than the small opening and equivalent to the electrode plate. A large opening having the same thickness as the electrode plate, and a step is formed on the inner periphery of the opening between the small opening and the large opening. Thus, compared to a sheet jig of a type in which a sheet and a plate-like member are bonded together, the overall rigidity is high, and the package substrate can be reliably held on the chuck table 14.

It is a perspective view which shows the structure of an example of a package substrate, a sheet jig | tool, and a processing apparatus. It is sectional drawing which shows a mounting process. It is sectional drawing explaining the state which mounts a sheet | seat on the outer periphery of the electrode board of a package substrate with a curvature in a holding surface sealing process. It is sectional drawing which shows the state which covers the outer periphery of an electrode plate with a sheet | seat so that a resin sealing layer may be exposed among the holding surface sealing processes. It is sectional drawing which shows a holding process. It is a perspective view which shows the structure of the 2nd example of a sheet jig | tool. It is sectional drawing which shows the structure of the 2nd example of a sheet jig | tool. It is sectional drawing which shows the holding process by the 2nd example of a sheet jig | tool. It is a perspective view which shows the structure of the 3rd example of a sheet jig | tool. It is sectional drawing which shows the structure of the 3rd example of a sheet jig. It is sectional drawing which shows the holding process by the 3rd example of a sheet jig | tool. It is a perspective view which shows the structure of the 4th example of a sheet jig | tool. It is sectional drawing which shows the structure of the 4th example of a sheet jig. It is sectional drawing which shows the holding process by the 4th example of a sheet jig | tool.

  The package substrate 1 shown in FIGS. 1 and 2 is an example of a rectangular package substrate, such as a CSP substrate or a QFN substrate. The package substrate 1 has an electrode plate 3 as a base, and a plurality of division lines (not shown) are formed on the surface 3 a of the electrode plate 3. In addition, a device chip is mounted in each area partitioned by the division lines. The device chip is connected to a wiring layer formed on the electrode plate 3. In addition, the device chip is sealed with a mold resin, and a sealing resin layer 2 configured by covering and sealing a plurality of devices with the mold resin is formed. In the sealing resin layer 2, a device chip is formed on the back surface of each region partitioned by the division line. The mold resin 2 side is ground by, for example, a grinding wheel.

  The electrode plate 3 of the package substrate 1 is configured to be larger than the resin sealing layer 2, and the outer peripheral edge 3 c of the electrode plate 3 shown in FIG. 2 protrudes outward from the resin sealing layer 2 and is exposed. . Further, due to the influence of heat or the like generated when the device chip is sealed with the resin sealing layer 2, the electrode plate 3 of the package substrate 1 is warped with the outer peripheral side curved upward. In other words, the outer peripheral edge 3c of the electrode plate 3 is curved so as to be turned up.

  With reference to FIGS. 1 and 2, the configuration of a processing apparatus 10 that performs predetermined grinding on various workpieces such as the package substrate 1 will be described. The processing device 10 has a device base 11 extending in the Y-axis direction. A chuck table 14 that can reciprocate in the Y-axis direction is provided on the upper surface 11 a of the apparatus base 11.

  As shown in FIG. 2, the chuck table 14 includes a holding unit 140 formed of a porous member such as porous ceramics. The holding unit 140 communicates with the suction source 15. By opening a valve (not shown), the suction force generated by the suction source 15 can be applied to the holding surface 141 that is the upper surface of the holding unit 140.

  The chuck table 14 holds the package substrate 1 via the sheet jig 4. As shown in FIG. 1, the sheet jig 4 includes a sheet 5 having an opening 5 a formed corresponding to the shape and size of the package substrate 1, and a ring frame attached to the periphery of the upper surface of the sheet 5. 6.

  The chuck table 14 includes a frame holding portion 142 that holds the ring frame 6 constituting the sheet jig 4. A plurality of frame holding portions 142 are arranged along the outer peripheral edge of the holding portion 140. The frame holding part 142 is made of, for example, a magnet. The number of frame holding parts 142 is not particularly limited. The frame holding part 142 may be formed in a ring shape.

  The opening 5 a of the sheet 5 is formed in a rectangular shape according to the shape and size of the rectangular package substrate 1, and is smaller than the electrode plate 3 constituting the package substrate 1 and larger than the resin sealing layer 2. It has a configuration. That is, the long side and short side of the opening 5 a are shorter than the long side and short side of the electrode plate 3 and longer than the long side and short side of the resin sealing layer 2. The sheet jig 4 shown in FIG. 1 has two openings 5a in the sheet 5, but the number is not particularly limited. The chuck table 14 can also suck and hold a disk-shaped plate workpiece.

  A column 12 is erected on the rear side in the Y-axis direction of the apparatus base 11 shown in FIG. On the side of the column 12, there is provided a grinding means 16 for grinding the package substrate 1 sucked and held by the chuck table 14 using the sheet jig 4. The grinding means 16 is driven by the grinding feed means 17 and can be moved up and down. The grinding means 16 includes a spindle unit 160 having a spindle having an axis in the Z-axis direction, a holder 161 that holds the outer peripheral side of the spindle unit 160, a motor 162 that rotates the spindle, and the spindles that constitute the spindle unit 160. A grinding wheel 164 mounted at the lower end of the grinding wheel 163 via a mount 163 and a grinding wheel 165 fixed in an annular shape at the lower part of the grinding wheel 164. Then, when the motor 162 rotates the spindle, the grinding wheel 164 can be rotated at a predetermined rotation speed.

  The grinding feed means 17 includes a ball screw 170 extending in the Z-axis direction, a motor 171 connected to one end of the ball screw 170, a pair of guide rails 172 extending parallel to the ball screw 170, and nuts provided therein are screwed onto the ball screw 170. And a lifting plate 173 whose side portion is in sliding contact with the guide rail 172 and whose holder 161 is fixed to one surface. The grinding feed means 17 is driven by a motor 171 so that the ball screw 170 rotates and moves the elevating plate 173 along the pair of guide rails 172 in the Z-axis direction, thereby moving the grinding means 16 together with the elevating plate 173 to the Z-axis. Can be raised and lowered in the direction.

  Next, a method for grinding the package substrate 1 using the processing apparatus 10 will be described. First, two package substrates 1 are prepared in accordance with the two openings 5 a formed in the sheet 5 of the sheet jig 4.

(1) Placement Step As shown in FIG. 2, the package substrate 1 is placed on the holding surface 141 of the chuck table 14. Specifically, the package substrate 1 is placed on the holding surface 141 of the holding unit 140 from the electrode plate 3 side, and the resin sealing layer 2 is exposed upward. At this time, since the package substrate 1 is curved so that the outer peripheral side is warped upward, the central portion of the electrode plate 3 of the package substrate 1 is in contact with the holding surface 141, but the outer peripheral edge 3 c of the electrode plate 3 is It will be in a non-contact state with respect to the holding surface 141. FIG.

(2) Holding surface sealing step As shown in FIGS. 3 and 4, the outer peripheral edge 3 c of the electrode plate 3 of the package substrate 1 is sealed by the sheet jig 4. Specifically, the seat 5 is placed on the holding surface 141 with the opening 5 a of the seat 5 being positioned at the center of the holding surface 141, and the ring frame 6 is placed on the frame holding portion 142. The ring frame 6 is held by the frame holding part 142 by magnetic force.

  When the ring frame 6 is fixed by the magnetic force of the frame holding part 142, the inner peripheral part 5b of the sheet 5 covers the outer peripheral edge 3c of the electrode plate 3 from above, and the resin from the opening 5a of the sheet 5 shown in FIG. The sealing layer 2 can be exposed.

(3) Holding Step As shown in FIG. 5, the sheet 5 and the package substrate 1 are sucked and held by the holding surface 141 of the chuck table 14. Specifically, a valve (not shown) is opened to allow the holding surface 141 to communicate with the suction source 15 so that the suction force of the suction source 15 acts on the holding surface 141, and the sheet 5 and the electrode plate 3 are sucked by the holding surface 141. . As the sheet 5 is pulled downward by the suction force, the inner peripheral portion 5b of the sheet 5 presses the outer peripheral edge 3c of the electrode plate 3 to correct the warpage of the outer peripheral edge 3c.

  In this manner, the entire back surface 3 b of the electrode plate 3 and the sheet 5 are brought into contact with the holding surface 141, and the package substrate 1 is sucked and held by the chuck table 14. At this time, since the entire holding surface 141 of the chuck table 14 is covered with the entire back surface 3 b of the electrode plate 3 and the sheet 5, air does not leak from the outer peripheral edge 3 c side of the electrode plate 3. Even if the inner peripheral portion 5b of the sheet 5 cannot sufficiently press the outer peripheral edge 3c of the electrode plate 3, a sealed space surrounded by the sheet 5, the electrode plate 3, and the holding surface 141 is formed. Therefore, air does not leak. Accordingly, the entire back surface 3b of the electrode plate 3 is sucked, and the warp of the package substrate 1 is corrected.

  When the chuck table 14 sucks and holds, for example, a disk-shaped plate-like workpiece, the plate-like workpiece can be directly sucked and held by the holding surface 141 of the chuck table 14. Further, when a rectangular package substrate having a different size from the package substrate 1 shown in FIG. 1 or the like is held, the size of the opening of the sheet may be changed in accordance with the shape of the package substrate. That is, it is possible to deal with package substrates having different sizes by simply adjusting the size of the opening.

(4) Grinding Step After the holding step, the package substrate 1 held on the chuck table 14 is ground using the grinding means 16 shown in FIG. Specifically, the chuck table 14 shown in FIG. 1 is moved below the grinding means 16. Resin sealing of the package substrate 1 with the rotating grinding wheel 165 while the grinding means 16 rotates the grinding wheel 164 and the grinding feed means 17 lowers the grinding means 16 in a direction approaching the holding surface 141 of the chuck table 14. The layer 2 is ground to the finished thickness of the package substrate 1. After the grinding process is performed, the package substrate 1 is unloaded from the holding surface 141 of the chuck table 14 using a conveying means (not shown).

Thus, in the grinding method of the package substrate of the present invention, the holding surface sealing process is performed after the mounting process, and the resin sealing layer 2 is formed from the opening 5a of the sheet 5 constituting the sheet jig 4. Since the holding step is performed after the outer peripheral edge 3c of the warped electrode plate 3 is covered with the inner peripheral portion 5b of the sheet 5 so as to be exposed, the chuck is formed according to the type of the package substrate to be ground. There is no need to replace the table itself, and the height of the holding surface 141 does not change. Therefore, for example, the rectangular package substrate 1 or the disk-shaped silicon wafer can be sucked and held using the same chuck table 14.
When carrying out the holding step, only the resin sealing layer 2 is exposed from the opening 5a of the sheet 5 according to the shape and size of the package substrate 1, and the electrode plate 3 and the sheet 5 are sucked by the holding surface 141. By doing so, since the inner peripheral portion 5b of the sheet 5 presses against the outer peripheral edge 3c of the electrode plate 3, it is possible to prevent the suction force from leaking from the holding surface 141 while correcting the warp of the electrode plate 3, and the chuck The package substrate 1 can be securely held by the table 14.

  A sheet jig 20 shown in FIGS. 6 and 7 is a second example of a sheet jig, and a plate-like member 23 is bonded to the lower surface of the sheet 5 constituting the sheet jig 4 described above. Specifically, the sheet jig 20 is attached to the periphery of the sheet 21 having the opening 21a corresponding to the shape and size of the package substrate, and the upper surface opposite to the contact surface 210 of the sheet 21 with which the package substrate contacts. The ring ring 22 is attached, and the plate member 23 is attached to the contact surface 210 of the seat 21. The opening 21 a of the sheet 21 is formed smaller than the electrode plate 3 of the package substrate 1 shown in FIG. 8 and larger than the resin sealing layer 2.

The plate-like member 23 has a thickness equivalent to that of the electrode plate 3 constituting the package substrate 1, that is, substantially the same thickness as the electrode plate 3. Further, as shown in FIG. 7, the plate-like member 23 attached to the contact surface 210 of the sheet 21 is larger than the opening 21 a of the sheet 21 and at least as large as the electrode plate 3, that is, An opening 23 a having the same size as the electrode plate 3 or slightly larger than the electrode plate 3 is provided. Thus, since the opening part 23a of the plate-shaped member 23 becomes a structure matched with the magnitude | size of the electrode plate 3, it is possible to accommodate the electrode plate 3 in the opening part 23a.

  The sheet jig 20 can be used in the above grinding method. As shown in FIG. 8, the mounting step and the holding surface sealing step are performed, the ring frame 22 is fixed by the magnetic force of the frame holding portion 142, and the outer peripheral edge 3 c of the electrode plate 3 is moved by the inner peripheral portion 21 b of the sheet 21. After the covering, a holding step of sucking and holding the package substrate 1 with the chuck table 14 using the sheet jig 20 is performed. With only the resin sealing layer 2 exposed from the opening 21a and the sheet jig 20 placed on the holding surface 141 of the chuck table 14, the suction force of the suction source 15 is applied to the holding surface 141, and the sheet 21, plate The member 23 and the electrode plate 3 are sucked by the holding surface 141.

  When the plate-like member 23 is pulled downward by the suction force, the plate-like member 23 pulls the sheet 21 toward the holding surface 141, and the inner peripheral portion 21 b of the sheet 21 presses the outer peripheral edge 3 c of the electrode plate 3. Correct 23 warpage. In this way, the entire surface of the back surface 3 b of the electrode plate 3, the plate-like member 3 and the sheet 21 are brought into contact with the holding surface 141, and the package substrate 1 is sucked and held by the chuck table 14. At this time, since the entire surface of the holding surface 141 is covered with the back surface 3b of the electrode plate 3, the plate-like member 23, and the sheet 21, air does not leak.

As described above, the sheet jig 20 is configured by providing the opening 23 a that can accommodate the electrode plate 3 on the contact surface 210 of the sheet 21 and attaching the plate-like member 23, and thus the holding surface 141 of the chuck table 14. By sucking the sheet 21, the plate-like member 23, and the electrode plate 3, the plate-like member 23 pulls the sheet 21 toward the holding surface 141, and the sheet 21 can press the outer peripheral edge 3 c of the electrode plate 3. Thereby, the warp of the electrode plate 3 can be effectively corrected, and the package substrate 1 can be sucked and held more securely by the chuck table 14.
Further, by providing the plate-like member 23, it is possible to prevent the inner peripheral portion 21b of the sheet 21 from rolling up. That is, by providing the plate-like member 23 having the same thickness as the electrode plate 3, the sheet 21 can be made flat even when the package substrate 1 is sucked and held, and the suction force inside the inner peripheral portion 21b does not reach. The possibility that the grinding water is sprayed on the portion and the sheet 21 is rolled up is eliminated.
The plate member 23 and the ring frame 22 may be attached to the same surface of the sheet 21. The opening 23 may be formed by sticking a plurality of plate-like members 23 to the sheet 21.

  The sheet jig 30 shown in FIGS. 9 and 10 is a third example of the sheet jig, and a plate-like member is attached to the lower surface of the sheet in accordance with the size of the chuck table without using a ring frame. Is. Specifically, as shown in FIG. 10, the sheet jig 30 includes a sheet 31 having an opening 31 a corresponding to the size of the package substrate 1 and a plate-like member attached to the contact surface 310 of the sheet 31. 32. The opening 31 a of the sheet 31 is formed smaller than the electrode plate 3 of the package substrate 1 shown in FIG. 11 and larger than the resin sealing layer 2.

  The plate-like member 32 has an outer diameter that is the same as or slightly larger than the outer diameter of the holding surface 141 of the chuck table 14. The plate-like member 32 has the same thickness as the electrode plate 3, that is, substantially the same thickness as the electrode plate 3, and is at least as large as the electrode plate 3, ie, the same size as the electrode plate 3 or the electrode plate. An opening 32 a having a size slightly larger than 3 is provided. Similarly to the sheet jig 20, the sheet jig 30 can accommodate the electrode plate 3 in the opening 32a.

  The sheet jig 30 can be used in the above grinding method. After performing the placing step and the holding surface sealing step, as shown in FIG. 11, a holding step of sucking and holding the package substrate 1 with the chuck table 14 using the sheet jig 30 is performed. With only the resin sealing layer 2 exposed from the opening 31a and the sheet jig 30 placed on the holding surface 141 of the chuck table 14, the suction force of the suction source 15 is applied to the holding surface 141, and the sheet 31, plate The member 32 and the electrode plate 3 are sucked by the holding surface 141.

  By pulling the plate-like member 32 downward, the plate-like member 32 pulls the sheet 31 toward the holding surface 141, whereby the inner peripheral portion 31 b of the sheet 31 presses the outer peripheral edge 3 c of the electrode plate 3, and the electrode plate 3. To correct the warp. In this way, the entire surface of the back surface 3 b of the electrode plate 3 and the plate-like member 32 are brought into contact with the holding surface 141, and the package substrate 1 is sucked and held by the chuck table 14. At this time, since the entire surface of the holding surface 141 is covered with the back surface 3b of the electrode plate 3 and the entire surface of the plate-like member 32, air does not leak.

  As described above, the sheet jig 30 is configured such that the entire lower surface of the plate-like member 31 having the opening 32 a that can accommodate the electrode plate 3 is sucked and held by the holding surface 141 of the chuck table 14. It is not necessary to fix the frame to the frame holding part 142, and the work load is reduced. In the sheet jig 30 as well, the sheet member 32 can press the outer peripheral edge 3c of the electrode plate 3 by pulling the sheet 31 to the holding surface 141 side as in the above-described sheet jig 20. In addition, the warping of the electrode plate 3 can be effectively corrected, and the package substrate 1 can be sucked and held more securely by the chuck table 14.

  The sheet jig 40 shown in FIGS. 12 and 13 is a fourth example of the sheet jig, and is configured by forming an opening 45 corresponding to the shape and size of the package substrate in the plate-like member 41. . The plate-like member 41 has an outer diameter that is the same as or slightly larger than the outer diameter of the holding surface 141 of the chuck table 14, and is thicker than the electrode plate 3 and has a finished thickness of the package substrate 1. It has a thinner thickness.

  An opening 45 is formed in the center of the plate-like member 41. The opening 45 has a small opening 42 that is smaller than the electrode plate 3 of the package substrate 1 shown in FIG. 14 and larger than the resin sealing layer 2. Further, below the small opening 42, the electrode has a thickness larger than that of the small opening 42 and equivalent to that of the electrode plate 3, and at least as large as the electrode plate 3, that is, as large as the electrode plate 3. A large opening 43 having a size slightly larger than that is provided. On the inner periphery of the opening 45, a step 46 is formed between the small opening 42 and the large opening 43. The large opening 43 can accommodate the electrode plate 3.

  The sheet jig 40 can be used in the above grinding method. After performing the placing step and the holding surface sealing step, as shown in FIG. 14, a holding step of sucking and holding the package substrate 1 with the chuck table 14 using the sheet jig 40 is performed. In a state where only the resin sealing layer 2 is exposed from the small opening 42 and the sheet jig 40 is placed on the holding surface 141 of the chuck table 14, the suction force of the suction source 15 is applied to the holding surface 141, and the plate-like member 41 and the electrode plate 3 are sucked by the holding surface 141.

  The plate-like member 41 is sucked and pulled downward, and the projecting portion 44 constituting the step 46 presses the outer peripheral edge 3 c of the electrode plate 3 to correct the warp of the electrode plate 3. In this way, the entire surface of the back surface 3 b of the electrode plate 3 and the plate-like member 41 are brought into contact with the holding surface 141, and the package substrate 1 is sucked and held by the chuck table 14. Similarly to the sheet jig 30, the sheet jig 40 also covers the entire holding surface 141 with the entire back surface 3 b of the electrode plate 3 and the entire plate-like member 41, so that air does not leak.

  Thus, since the sheet jig 40 is composed entirely of the plate-like member 41, the sheet jig 40 has higher rigidity and weight than the sheet jig of the type in which the sheet and the plate-like member are bonded together. The package substrate can be securely held on the table 14.

The materials of the sheets 5, 21 and 31 are not particularly limited, and may be formed of, for example, PET (polyethylene terephthalate) or plastic.
That is, the sheet 5 may be made of any material that has a certain degree of hardness so that the electrode plate 3 can be pressed and can prevent air leakage by contacting the electrode plate.

  Further, the material of the plate-like members 23, 32 and 41 is not particularly limited, but is made of, for example, SUS.

DESCRIPTION OF SYMBOLS 1: Package board | substrate 2: Resin sealing layer 3: Electrode board 3a: Front surface 3b: Back surface 3c: Outer peripheral edge 4: Sheet jig | tool 5: Sheet 5a: Opening part 5b: Inner peripheral part 6: Ring frame 10: Processing apparatus 11 : Device base 11a: upper surface 12: column 13: moving base 14: chuck table 140: holding unit 141: holding surface 142: frame holding unit 15: suction source 16: grinding means 160: spindle unit 161: holder 162: motor 163 : Mount 164: Grinding wheel 165: Grinding wheel 17: Grinding feed means 170: Ball screw 171: Motor 172: Guide rail 20: Sheet jig 21: Sheet 210: Contact surface 21 a: Opening 21 b: Inner peripheral part 22: Ring frame 23: plate-like member 23a: opening 30: sheet jig 31: sheet 310: contact surface 31 : Opening 31b: inner peripheral portion 32: plate member 32a: opening 40: sheet jig 41: plate-shaped member 42: small opening section 43: large opening 44: protruding portion 45: opening 46: step

Claims (5)

An electrode plate having a plurality of division lines formed on the surface, and a device is formed on the back surface of each region partitioned by the division lines, and a part of the electrode plate is exposed on the outer peripheral side to resin the plurality of devices. A package substrate grinding method for grinding the encapsulation resin layer of the package substrate having a warp to a desired thickness.
A mounting step of mounting the package substrate on the chuck table;
A holding surface sealing step for covering the outer peripheral side of the electrode plate so that the sealing resin layer is exposed by a sheet having an opening smaller than the electrode plate and larger than the sealing resin layer;
A holding step of sucking and holding the sheet and the package substrate on the chuck table;
A grinding step of thinning the package substrate to a finished thickness by grinding the sealing resin layer by a grinding means equipped with a grindstone;
A grinding method comprising: A sheet jig used in the grinding method according to claim 1,
Ring,
A sheet jig comprising: a sheet attached to the ring and having an opening smaller than the electrode plate of the package substrate and larger than the sealing resin layer.   A plate-like member having a thickness equivalent to that of the electrode plate and having at least an opening having a size equivalent to that of the electrode plate is attached to a surface of the sheet facing the chuck table. 2. The sheet jig according to 2. A sheet jig used in the grinding method according to claim 1,
A plate-like member having at least an outer diameter equivalent to the outer diameter of the holding surface of the chuck table and having a thickness equivalent to the electrode plate, and at least an opening having a size equivalent to the electrode plate;
A sheet jig, comprising: a sheet attached to the plate-like member and having an opening that is smaller than the electrode plate and larger than the sealing resin layer. A sheet jig used in the grinding method according to claim 1,
It has an outer diameter equivalent to at least the outer diameter of the holding surface of the chuck table, and is composed of a plate-like member that is thicker than the electrode plate and thinner than the finished thickness of the package substrate,
Having an opening in the center,
The opening is a small opening formed smaller than the electrode plate and larger than the sealing resin layer, and is formed larger than the small opening and the same size as the electrode plate. It consists of a large opening with a thickness,
A sheet jig in which a step is formed between the small opening and the large opening on the inner periphery of the opening.

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