Peeling method of resin sheet

Abstract

The present application provides a resin sheet peeling method capable of easily forming a peeling starting point of a resin sheet closely adhered to a plate-shaped object. The resin sheet peeling method peels a resin sheet from a plate-shaped object to which the resin sheet is adhered, wherein the resin sheet peeling method includes a resin sheet heating step of heating an end portion of the resin sheet of the plate-shaped object to which the resin sheet is adhered to cause the resin sheet to turn up from the end portion to form a peeling starting point, and a resin sheet removing step of peeling the resin sheet from the peeling starting point to remove the resin sheet from the plate-shaped object.

Description

TECHNICAL FIELD

[0001] The present application relates to a resin sheet peeling method. BACKGROUND

[0002] There is known a processing technique of thinning a board-shaped work such as a semiconductor wafer, a resin package substrate, a glass substrate, a ceramic substrate, or the like by grinding with a grinding wheel or dividing by a cutting tool or a laser beam. At the time of such processing, an adhesive sheet for protecting a surface of the work on which a device is formed is attached to the front surface of the work. The adhesive sheet is strongly attached by a strong adhesive layer so as not to be peeled off during the processing. At the time of peeling the adhesive sheet, a technique of strongly fixing a heat staking sheet for peeling to the adhesive sheet and pulling the heat staking sheet to peel the adhesive sheet from the work is used (see Patent Literature 1).

[0003] Patent Literature 1: Japanese Patent Application Laid-Open No. 2012-028478

[0004] However, in the above-described method, other consumables such as the heat staking sheet are required, which leads to an increase in cost. Although a technique of peeling by inserting a claw portion between the resin sheet and the work without using the heat staking sheet has been developed, there is a problem that it is difficult to make the claw enter to form a peeling starting point in the case where the resin sheet is strongly attached. SUMMARY

[0005] According to the present application, it is possible to easily form a peeling starting point of a resin sheet strongly attached to a board-shaped object.

[0006] According to the present application, there is provided a resin sheet peeling method of peeling a resin sheet from a board-shaped object to which the resin sheet is attached, the resin sheet peeling method including: a resin sheet heating step of heating an end portion of the resin sheet of the board-shaped object to which the resin sheet is attached to turn up the resin sheet from the end portion to form a peeling starting point; and a resin sheet removing step of peeling the resin sheet from the peeling starting point to remove the resin sheet from the board-shaped object.

[0007] It is preferable that the resin sheet be a resin sheet having no adhesive material layer.

[0008] It is preferable that the resin sheet have a region having no adhesive material layer in a region attached to the board-shaped object.

[0009] It is preferable that, in the resin sheet heating step, the resin sheet be heated through the board-shaped object.

[0010] According to the present application, it is possible to easily form a peeling starting point of a resin sheet strongly attached to a board-shaped object. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 is an exploded perspective view of the sheet-equipped board used in the resin sheet peeling method of the embodiment of the present application.

[0012] Figure 2 is Figure 1 is a perspective view of the sheet-equipped board.

[0013] Figure 3 is a cross-sectional view showing a part of Figure 2

[0014] Figure 4 is a side view of a processing example of the sheet-equipped board shown in Figure 1

[0015] Figure 5 is a flowchart showing the flow of the resin sheet peeling method of the embodiment.

[0016] Figure 6 is a side view of an example of the resin sheet heating step of the resin sheet peeling method shown in Figure 5

[0017] is a side view of another example of the resin sheet heating step of the resin sheet peeling method shown in Figure 7 Figure 5

[0018] Figure 8 is a side view of an example of the resin sheet removing step of the resin sheet peeling method shown in Figure 5

[0019] is a side view of another example of the resin sheet removing step of the resin sheet peeling method shown in Figure 9 Figure 5

[0020] Figure 10 is a side view of yet another example of the resin sheet removing step of the resin sheet peeling method shown in Figure 5

[0021] Explanation of Reference Numerals

[0022] 10: board; 12: front surface; 15: back surface; 18: resin sheet; 19: adhesive surface; 20: sheet-equipped board; 21: peeling starting point; 50: heating table; 55: work table; 57: warm air dryer; 60: removing unit; 65: air jetting unit; 70: peeling tape; 72: removing unit; ST1: resin sheet heating step; ST2: resin sheet removing step. DETAILED DESCRIPTION

[0023] ​​​​​​​Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the constituent elements described below include contents that are readily conceived by those skilled in the art and substantially the same. Additionally, the structures described below can be appropriately combined. Furthermore, various omissions, substitutions, or modifications to the structure can be made without departing from the spirit of the present invention.

[0024] The method for peeling off the resin sheet 18 according to the embodiments will be described with reference to the accompanying drawings. First, the structure of the sheet-like material 20 used in the method for peeling off the resin sheet 18 according to the embodiments will be described. Figure 1 This is an exploded perspective view of the plate-like object 20 with a sheet used in the peeling method of the resin sheet 18 in the embodiment. Figure 2 yes Figure 1 A perspective view of the plate-like object 20 with sheets shown. Figure 3 It is Figure 2 A partially enlarged cross-sectional view is shown. The plate-like structure 20 with the sheet has a plate-like structure 10 and a resin sheet 18.

[0025] The plate-shaped object 10 is a wafer such as a semiconductor wafer or optical device wafer with a substrate 11 made of silicon, sapphire, SiC (silicon carbide), or gallium arsenide. The plate-shaped object 10 has multiple predetermined dividing lines 13 formed on the front side 12 of the substrate 11 and devices 14 formed in each region divided by the multiple predetermined dividing lines 13 in a grid pattern. The side of the substrate 11 opposite to the front side 12 where the devices 14 are formed is designated as the back side 15. The plate-shaped object 10 is divided along the predetermined dividing lines 13 to form chips 16. In an embodiment, as... Figure 3 As shown, the plate-shaped object 10 has a plurality of electrode bumps 17 mounted on its front side 12, but in this invention, the electrode bumps 17 may not be mounted. The electrode bumps 17 protrude from the front side 12 of the device 14. The plate-shaped object 10 has irregularities on the front side 12 of the device 14 by mounting the electrode bumps 17.

[0026] The resin sheet 18 is adhered to the front surface 12 of the plate-shaped object 10 with one side serving as the adhesive surface 19, thereby protecting the device 14. The resin sheet 18 is formed into a circular plate with the same diameter as the plate-shaped object 10. The resin sheet 18 is a thermoplastic synthetic resin. The resin sheet 18 is, for example, made of polyolefin resin. In this embodiment, the resin sheet 18 is a resin sheet without a layer of adhesive material such as paste in the area where it is adhered to the plate-shaped object 10. In this embodiment, the resin sheet 18 is a resin sheet without a layer of adhesive material such as paste. When the resin sheet 18 does not have an adhesive layer such as paste, for example, by using a roller or pressing member to apply a radial tension in the surface direction to the resin sheet 18, it is stretched and pressed tightly against the plate-shaped object 10, thereby adhering it to the plate-shaped object 10.

[0027] In the embodiment, the resin sheet 18 is composed of only a base material layer composed of a thermoplastic resin such as a polyolefin resin, but in the present application, it is also possible to have a base material layer and an adhesive material layer. The resin sheet 18 can have, for example, an adhesive material layer and a base material layer provided outside the region to be attached to the plate-shaped object 10, or can have an adhesive material layer and a base material layer attached to the plate-shaped object 10.

[0028] Next, an example of processing of the sheet-equipped plate-shaped object 20 as a processing target will be described. Figure 4 is a side view of the sheet-equipped plate-shaped object processing example shown in Figure 1 is a side view of the sheet-equipped plate-shaped object processing example shown in Figure 4 An example shown in is a grinding processing of thinning the plate-shaped object 10 to a prescribed thickness by grinding the plate-shaped object 10 from the back surface 15 by the grinding unit 40.

[0029] In the grinding processing, first, the sheet-equipped plate-shaped object 20 is placed in a manner that the front surface 12 side of the plate-shaped object 10 opposes the holding surface 31 of the chuck table 30. The plate-shaped object 10 is suction-held to the holding surface 31 of the chuck table 30 with the resin sheet 18 attached to the front surface 12 interposed therebetween. The device 14 formed on the front surface 12 of the plate-shaped object 10 is protected from damage due to attachment or contact of foreign matter by the resin sheet 18.

[0030] In the grinding processing, next, the chuck table 30 is rotated around the shaft center 32 and the grinding wheel 41 of the grinding unit 40 is rotated around the shaft center 42. In the grinding processing, next, the grinding tool 43 of the grinding wheel 41 is brought close to the chuck table 30 at a prescribed feed rate while the grinding water 46 is supplied by the grinding water supply unit 45. When the grinding tool 43 comes into contact with the back surface 15 of the plate-shaped object 10, the grinding tool 43 grinds the back surface 15 side of the plate-shaped object 10. When the plate-shaped object 10 is thinned to a prescribed thickness by the grinding unit 40, the suction holding of the chuck table 30 is released and the grinding processing is ended.

[0031] Next, a peeling method of the resin sheet 18 of the embodiment will be described. Figure 5 is a flowchart showing a flow of the peeling method of the resin sheet 18 of the embodiment. The peeling method of the resin sheet 18 is a method of peeling the resin sheet 18 from the plate-shaped object 10 to which the resin sheet 18 is attached Figure 2 and Figure 3 The method of peeling the plate-shaped object 10 shown in Figure 5 The method shown in includes a resin sheet heating step ST1 and a resin sheet removal step ST2.

[0032] First, the resin sheet heating step ST1 will be explained. The resin sheet heating step ST1 is a step of heating the end of the resin sheet 18 of the plate-shaped object 10 to which the resin sheet 18 is attached, so that the resin sheet 18 is flipped up from the end to form a peeling start point 21.

[0033] Figure 6 Shown in partial cross-section Figure 5 A side view of an example of the resin sheet heating step ST1 in the method for peeling resin sheet 18 shown. Figure 6 In one example shown, during the resin sheet heating step ST1, the plate-shaped object 20 with the sheet is first placed on the mounting surface 51 of the heating stage 50. At this time, the plate-shaped object 20 with the sheet is positioned such that the back side 15 of the plate-shaped object 10 contacts the mounting surface 51, and the resin sheet 18 is the upper surface side. The heating stage 50 is provided with a heating element 52 at a position where at least the outer peripheral portion of the plate-shaped object 20 with the sheet can be heated. Figure 6 In one example shown, the heating element 52 is disposed along the entire surface of the plate-like object 20 on which the sheet is placed.

[0034] exist Figure 6 In one example shown, in the resin sheet heating step ST1, the heating element 52 of the heating stage 50 is then heated by applying voltage or the like. Heating of the heating element 52 heats the mounting surface 51 of the heating stage 50. The heating stage 50 heats the plate-shaped object 20 with the sheet by the temperature rise of the mounting surface 51. The heating stage 50 heats the resin sheet 18 through the plate-shaped object 10. The front surface temperature of the mounting surface 51 is 80°C or higher when the resin sheet 18 is a polyolefin resin sheet, preferably 110°C or higher.

[0035] The resin sheet 18 with the plate-like structure 20 is thermoplastic and therefore softens and deforms upon heating. In contrast, the plate-like structure 10, which is a wafer, has a lower coefficient of linear expansion than the resin sheet 18, and therefore undergoes less deformation upon heating. As a result, the resin sheet 18, deformed by heating, folds up relative to the plate-like structure 10 from its outer peripheral end. A peeling start point 21 is formed at the end of the resin sheet 18.

[0036] Figure 7 Shown in partial cross-section Figure 5 A side view of another example of the resin sheet heating step ST1 in the method for peeling resin sheet 18 shown. Figure 7 In one example shown, during the resin sheet heating step ST1, the plate-shaped object 20 with the sheet is first placed on the mounting surface 56 of the worktable 55. At this time, the plate-shaped object 20 with the sheet is placed such that the back side 15 of the plate-shaped object 10 is in contact with the mounting surface 56 and the resin sheet 18 is the upper surface side.

[0037] exist Figure 7In the example shown, in the resin sheet heating step ST1, the sheet-attached plate 20 is heated by the hot air 58 of the warm air dryer 57. In the resin sheet heating step ST1, it is preferable to direct the hot air 58 of the warm air dryer 57 toward the end portion of the sheet-attached plate 20 as the outer peripheral portion. The heated end portion of the resin sheet 18 is softened and deformed. The heated and deformed end portion of the resin sheet 18 is turned up with respect to the plate 10. A peeling starting point 21 is formed at the end portion of the resin sheet 18.

[0038] In the above description, two heating methods are exemplified, but the heating method in the resin sheet heating step ST1 is not particularly limited as long as it is at least capable of heating the end portion of the resin sheet 18. The heating method can use, for example, electromagnetic waves such as far infrared rays.

[0039] Next, the resin sheet removing step ST2 will be described. The resin sheet removing step ST2 is a step of peeling the resin sheet 18 from the peeling starting point 21 after the resin sheet heating step ST1 and removing the resin sheet 18 from the plate 10. In the following description, the resin sheet removing step ST2 is described as a step performed after the resin sheet heating step ST1 in the example shown, but it can be performed after the resin sheet heating step ST1 in the other example shown. Figure 6 Next, the resin sheet removing step ST2 will be described. The resin sheet removing step ST2 is a step of peeling the resin sheet 18 from the peeling starting point 21 after the resin sheet heating step ST1 and removing the resin sheet 18 from the plate 10. In the following description, the resin sheet removing step ST2 is described as a step performed after the resin sheet heating step ST1 in the example shown, but it can be performed after the resin sheet heating step ST1 in the other example shown. Figure 7 Next, the resin sheet removing step ST2 will be described. The resin sheet removing step ST2 is a step of peeling the resin sheet 18 from the peeling starting point 21 after the resin sheet heating step ST1 and removing the resin sheet 18 from the plate 10. In the following description, the resin sheet removing step ST2 is described as a step performed after the resin sheet heating step ST1 in the example shown, but it can be performed after the resin sheet heating step ST1 in the other example shown.

[0040] Figure 8 is a side view of an example of the resin sheet removing step ST2 of the peeling method of the resin sheet 18 shown in FIG. 1. In the example shown, the resin sheet removing step ST2 is performed after the resin sheet heating step ST1. Figure 5 is a side view of an example of the resin sheet removing step ST2 of the peeling method of the resin sheet 18 shown in FIG. 1. In the example shown, the resin sheet removing step ST2 is performed after the resin sheet heating step ST1. Figure 8 In the example shown, in the resin sheet removing step ST2, first, the end portion of the resin sheet 18 as the peeling starting point 21 formed by the resin sheet heating step ST1 is gripped by the gripping portion 61 of the removing unit 60.

[0041] In the example shown, in the resin sheet removing step ST2, first, the end portion of the resin sheet 18 as the peeling starting point 21 formed by the resin sheet heating step ST1 is gripped by the gripping portion 61 of the removing unit 60. Figure 8 In the example shown, in the resin sheet removing step ST2, next, the heating stage 50 is moved in the horizontal direction parallel to the placement surface 51 and in the direction indicated by the arrow in the drawing from the center of the placement surface 51 toward the portion gripped by the gripping portion 61 of the peeling starting point 21 by the moving unit 53. Figure 8 In the example shown, in the resin sheet removing step ST2, first, the end portion of the resin sheet 18 as the peeling starting point 21 formed by the resin sheet heating step ST1 is gripped by the gripping portion 61 of the removing unit 60.

[0042] Figure 9 is a side view of an example of the resin sheet removing step ST2 of the peeling method of the resin sheet 18 shown in FIG. 1. In the example shown, the resin sheet removing step ST2 is performed after the resin sheet heating step ST1. Figure 5A side view of another example of the resin sheet removal step ST2 of the method for peeling resin sheet 18 shown. Figure 9 In one example shown, in the resin sheet removal step ST2, air 66 from the air jet unit 65 is sprayed from the side of the sheet-like object 20 placed on the mounting surface 51 of the heating stage 50 toward the peeling starting point 21. The air jet unit 65 provides air 66 between the sheet-like object 10 and the resin sheet 18, thereby peeling the remaining adhesive surface 19 of the resin sheet 18 from the front surface 12 of the sheet-like object 10, starting from the peeling starting point 21. Thus, the resin sheet 18 is removed from the sheet-like object 10.

[0043] Figure 10 Shown in partial cross-section Figure 5 A side view of yet another example of the resin sheet removal step ST2 of the method for peeling off resin sheet 18 shown. Figure 10 In one example shown, in the resin sheet removal step ST2, a peeling tape 70 is first attached to the end of the resin sheet 18 that serves as the peeling starting point 21, formed by the resin sheet heating step ST1. At this time, one end 71 of the peeling tape 70 is attached in a manner that extends from the outer periphery of the resin sheet 18 to the outside. Figure 10 In one example shown, in the resin sheet removal step ST2, the holding part 73 of the removal unit 72 then holds one end 71 of the stripping tape 70.

[0044] exist Figure 10 In one example shown, in the resin sheet removal step ST2, the heating stage 50 is then moved by the moving unit 53 to a horizontal direction parallel to the mounting surface 51, and to the portion held by the holding part 73 from the center of the mounting surface 51 toward the peeling start point 21. Figure 10 The removal unit 72 moves in the direction indicated by the middle arrow, and moves upward in a direction perpendicular to the mounting surface 51. The holding portion 73 of the removal unit 72 moves relative to the holding portion of the resin sheet 18 toward the center of the plate-shaped object 20 with the sheet, thereby peeling the remaining adhesive surface 19 of the resin sheet 18 from the front surface 12 of the plate-shaped object 10 with the peeling starting point 21 by means of the peeling tape 70. Thus, the resin sheet 18 is removed from the plate-shaped object 10.

[0045] In the above description, three removal methods are illustrated, but the removal method in resin sheet removal step ST2 is not particularly limited as long as it can grasp and peel the resin sheet 18 from the peeling point 21 or promote the peeling of the resin sheet 18 from the peeling point 21. In resin sheet removal step ST2, the heating of the resin sheet 18 can continue from the resin sheet heating step ST1.

[0046] As explained above, in the peeling method of the resin sheet 18 of the embodiment, the resin sheet 18 is peeled from the peeling starting point 21 formed at the end portion of the resin sheet 18, thereby removing the resin sheet 18 from the plate-like article 10. The peeling starting point 21 is formed by heating the end portion of the resin sheet 18. Due to the thermoplasticity of the resin sheet 18 and the difference in the linear expansion coefficient from the plate-like article 10, when the resin sheet 18 is heated, a phenomenon of naturally turning up from the end portion occurs. That is, by heating at least the end portion of the resin sheet 18, the end portion as the outer periphery of the resin sheet 18 can be turned up, and thus even the resin sheet 18 firmly adhered to the plate-like article 10 can be easily formed with the peeling starting point 21. By forming the peeling starting point 21, the remaining adhered surface 19 of the resin sheet 18 can be easily peeled from the front surface 12 of the plate-like article 10 with the peeling starting point 21 as a starting point.

[0047] In addition, in the case of the resin sheet 18 without the adhesive layer such as a paste, when the resin sheet 18 is adhered, a tension in the surface direction and radially is given, and thus by heating, an effect that the end portion of the resin sheet 18 is more easily turned up is exerted. In addition, the resin sheet 18 without the adhesive layer such as a paste is difficult to control the adhering force, for example, compared with an adhesive sheet having a UV-hardening-type paste layer that is hardened by UV, and the like, and thus the peeling method of the resin sheet of the present application is more useful.

[0048] In addition, the present application is not limited to the above-described embodiments. That is, various modifications can be made and implemented within the scope of the gist of the present application.

Claims

1. A method for peeling a resin sheet from a plate to which the resin sheet is adhered, wherein the resin sheet has no adhesive material layer in at least the area where it is adhered to the plate, wherein, The coefficient of linear expansion of the plate is lower than that of the resin sheet, and the deformation of the plate due to heating is smaller. The method for peeling off the resin sheet comprises the following steps: In the resin sheet heating step, the end of the resin sheet of the plate to which the resin sheet is attached is heated, so that the resin sheet is deformed and flipped up from the end relative to the plate to form a peeling start point. The resin sheet is given a surface-direction and radial tension, and is stretched and tightly attached to the plate while being attached to the plate. as well as The resin sheet removal step involves peeling the resin sheet off from the plate-like material from the peeling starting point.

2. The method for peeling off the resin sheet according to claim 1, wherein, In the resin sheet heating step, the resin sheet is heated through the plate-like object.

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