Method for removing a carrier plate

Abstract

The present application provides a method for removing a carrier plate from a workpiece. The method is used when the carrier plate is peeled off and removed from a workpiece that is a disc-shaped composite substrate provided with the workpiece on the front surface of the carrier plate by means of a temporary adhesive layer. The method includes the following steps: a step difference forming step, in which the outer peripheral portion of the workpiece, the outer peripheral portion of the temporary adhesive layer, and the outer peripheral portion of the front surface side of the carrier plate are removed to form a step difference portion in which the back surface side of the carrier plate protrudes sideways compared to the front surface side of the carrier plate; a starting point area forming step, in which a starting point area that becomes the starting point when the carrier plate is peeled off from the workpiece is formed; a holding step, in which the workpiece is held from above using a holding unit after the step difference portion and the starting point area are formed; and a carrier plate removing step, in which, after the workpiece is held using the holding unit, a downward force is applied to the step difference portion to move the carrier plate in a direction away from the workpiece, thereby peeling off and removing the carrier plate from the workpiece.

Description

TECHNICAL FIELD

[0001] The present application relates to a removal method of a carrier plate used when removing the carrier plate from a workpiece provided on the front surface of the carrier plate by means of a temporary adhesive layer. BACKGROUND

[0002] In electronic devices typified by mobile phones or personal computers, a device chip having a device such as an electronic circuit becomes a necessary constituent element. For the device chip, for example, a front surface of a wafer formed of a semiconductor material such as silicon is divided into a plurality of regions by using a division predetermined line (a separation line), and a device is formed in each region, and then the wafer is divided along the division predetermined line, thereby obtaining the device chip.

[0003] The device chip obtained by the above-described method is, for example, fixed to a mother substrate for CSP (Chip Size Package), and electrically connected to a terminal or the like of the mother substrate by a wire bonding or the like, and then sealed with a molding resin. In this way, a package device is formed by sealing the device chip with the molding resin, and thus the device chip can be protected from external causes such as impact, light, heat, water, and the like.

[0004] In recent years, a packaging technology called FOWLP (Fan-Out Wafer Level Package) has been adopted: a redistribution technology at the wafer level is used to form a package terminal outside the region of the device chip (for example, refer to Patent Literature 1). In addition, a packaging technology called FOPLP (Fan-Out Panel Level Packaging) has been proposed: a package device is manufactured using a panel (typically, a glass substrate for manufacturing a liquid crystal panel) larger in size than a wafer.

[0005] In the FOPLP, for example, a wiring layer (RDL: Redistribution Layer) is formed on the front surface of a carrier plate serving as a temporary substrate by means of a temporary adhesive layer, and a device chip is bonded on the wiring layer. Next, the device chip is sealed with a molding resin, and a package panel is obtained. Then, the package panel is thinned by grinding or the like, and the package panel is divided, thereby completing a package device.

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2016-201519

[0007] In the above-described FOPLP, for example, after the package panel is divided into package devices, the carrier plate is removed from the package devices. Specifically, each package device is picked up from the carrier plate. However, when the size of the package device is small, it is difficult to pick up the package device from the carrier plate.

[0008] On the other hand, peeling and removing the carrier sheet from the packaging panel before the packaging panel is divided into packaged devices is also considered. However, the temporary adhesive layer has a certain level of adhesive strength, and thus it is difficult to peel the carrier sheet from the packaging panel without damaging the packaging panel or the carrier sheet. SUMMARY

[0009] The present application has been achieved in view of such a point, and aims to provide a carrier sheet removal method capable of easily removing a carrier sheet from a work such as a packaging panel.

[0010] According to one embodiment of the present application, a carrier sheet removal method is provided, which is used when a carrier sheet is peeled and removed from a work of a disc-shaped composite substrate provided with the work on a front surface of the carrier sheet by means of a temporary adhesive layer, and which includes a step of: a step of forming a step difference portion, in which an outer peripheral portion of the work, an outer peripheral portion of the temporary adhesive layer, and an outer peripheral portion of the front surface side of the carrier sheet are removed, and a step difference portion in which a back surface side of the carrier sheet protrudes laterally from the front surface side of the carrier sheet is formed; a step of forming a starting point region, in which a region of a portion of the work adjacent to the outer peripheral portion of the work is removed, and a starting point region that becomes a starting point when the carrier sheet is peeled from the work is formed; a holding step of holding the work from above using a holding unit in a state in which the work is positioned above the carrier sheet after the step difference portion and the starting point region are formed; and a carrier sheet removal step of moving the carrier sheet in a direction away from the work by applying a downward force to the step difference portion using a pushing member after the work is held using the holding unit, and thereby peeling and removing the carrier sheet from the work.

[0011] In one embodiment of the present application, in the carrier sheet removal step, a downward force is applied to the step difference portion after a fluid is blown against the temporary adhesive layer exposed between the work and the carrier sheet, or a downward force is applied to the step difference portion while a fluid is blown against the temporary adhesive layer exposed between the work and the carrier sheet, and the carrier sheet is peeled and removed from the work.

[0012] In addition, in one embodiment of the present application, in the carrier sheet removal step, a downward force can be applied to the step difference portion in a state in which the work and the carrier sheet are sunk into a liquid. In addition, a surfactant can be contained in the liquid.

[0013] In addition, in one embodiment of the present application, in the carrier sheet removal step, a downward force can be applied to the step difference portion in a state in which the work and the carrier sheet are sunk into the liquid, while imparting vibration to the pushing member.

[0014] Further, in one embodiment of the present application, the step of removing the carrier sheet can be performed while the workpiece and the carrier sheet are immersed in the liquid and a downward force is applied to the stepped portion while imparting vibration to the liquid.

[0015] In the method of removing the carrier sheet according to one embodiment of the present application, the outer peripheral portion of the workpiece, the outer peripheral portion of the temporary adhesive layer, and the outer peripheral portion of the front surface side of the carrier sheet are removed, a stepped portion in which the back surface side of the carrier sheet protrudes laterally more than the front surface side of the carrier sheet is formed, and a region of a portion of the workpiece adjacent to the outer peripheral portion of the workpiece is removed, thereby forming a starting point region that becomes a starting point when the carrier sheet is peeled from the workpiece. Thus, the workpiece is held from above by the holding unit, and a downward force is applied to the stepped portion, so that the carrier sheet can be easily peeled from the workpiece and removed with the starting point region as a starting point. Further, the gravitational force acting on the carrier sheet is used together with the downward force applied to the stepped portion, so that a large force is not required when the carrier sheet is removed from the workpiece. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a perspective view showing a structure example of a disc-shaped composite substrate including a carrier sheet and a workpiece.

[0017] Figure 2 (A) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate, Figure 2 (B) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate, Figure 2 (A) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate,

[0018] Figure 3 (A) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate, Figure 3 (B) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate,

[0019] Figure 4 (A) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate, Figure 4 (B) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate,

[0020] Figure 5 is a cross-sectional view showing a structure example of a composite substrate,

[0021] Figure 6 (A) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate, Figure 6 (B) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate, Figure 6 (C) of FIG. 1 is a cross-sectional view showing a structure example of a composite substrate,

[0022] Figure 7is a plan view showing a starting point region formed by a removal method of a carrier sheet of a first modification example.

[0023] Figure 8 (A) of FIG. 1 is a sectional view showing a case where the carrier sheet is peeled from the workpiece by a removal method of the carrier sheet of a second modification example, Figure 8 (B) of FIG. 1 is a sectional view showing a case where the carrier sheet is peeled from the workpiece by a removal method of the carrier sheet of a third modification example.

[0024] Explanation of Reference Numerals

[0025] 1: composite substrate; 3: carrier sheet; 3a: first surface (front surface); 3b: second surface (back surface); 3c: stepped portion; 5: temporary adhesive layer; 5a: central portion; 5b: outer peripheral portion; 5c: first portion; 5d: second portion; 7: workpiece; 7a: first surface (front surface); 7b: starting point region; 7c: starting point region; 9: device chip; 11: molded resin layer; 2: cutting device; 4: chuck table; 6: frame; 6a: flow path; 8: holding plate; 8a: holding surface; 10: valve; 12: suction source; 14: cutting unit; 16: spindle; 18: cutting tool; 22: peeling device; 24: holding unit; 24a: holding surface; 26: push member; 32: nozzle; 34: fluid; 42: groove; 44: liquid. DETAILED DESCRIPTION

[0026] An embodiment of one mode of the present application will be described with reference to the drawings. Figure 1 is a perspective view showing a structure example of a disc-shaped composite substrate 1 used in a removal method of a carrier sheet of the present embodiment, Figure 2 (A) of FIG. 1 is a sectional view showing a structure example of the composite substrate 1, Figure 2 (B) of FIG. 1 is a sectional view showing a structure example of the composite substrate 1, Figure 2 (A) of FIG. 1 is a sectional view showing a structure example of the composite substrate 1,

[0027] The composite substrate 1 includes, for example, a carrier sheet 3 formed of an insulator material such as soda lime glass, borosilicate glass, quartz glass, or the like. The carrier sheet 3 has a substantially flat first surface (front surface) 3a and a second surface (back surface) 3b on the side opposite to the first surface 3a, and is configured in a disc shape in which the shape as viewed from the first surface 3a side or the second surface 3b side is circular. The thickness of the carrier sheet 3 is, for example, 2 mm or less, and is typically 1.1 mm.

[0028] In the present embodiment, the carrier sheet 3 formed of an insulator material such as soda lime glass, borosilicate glass, quartz glass, or the like is used, but there is no particular limitation on the material, configuration, size, or the like of the carrier sheet 3. For example, a sheet formed of a material such as a semiconductor, ceramic, resin, metal, or the like can also be used as the carrier sheet 3.

[0029] A workpiece 7 is disposed on the first surface 3a side of the carrier plate 3 by means of a temporary adhesive layer 5. The temporary adhesive layer 5 is formed on the substantially whole of the first surface 3a by overlapping metal films or insulating films, for example, and has the function of bonding the carrier plate 3 and the workpiece 7. In addition, the temporary adhesive layer 5 is sometimes also composed of a resin film or the like that, which functions as an adhesive.

[0030] The thickness of the temporary adhesive layer 5 is, for example, 20 μm or less, typically 5 μm. This temporary adhesive layer 5 includes: a central portion 5a that bonds the carrier plate 3 and the workpiece 7; and an outer peripheral portion 5b that covers the first surface 3a of the outer periphery of the carrier plate 3. Furthermore, the outer peripheral portion 5b of the temporary adhesive layer 5 is firmly bonded to the carrier plate 3 and is not easily peeled off.

[0031] When the carrier plate 3 is peeled off from the workpiece 7, the central portion 5a of the temporary adhesive layer 5 separates into a first portion 5c that is tightly attached to the side of the carrier plate 3 (see reference). Figure 6 (C) and the second part 5d that is closely attached to the side of workpiece 7 (refer to) Figure 6 (C)). Before peeling the carrier plate 3 from the workpiece 7, it is preferable to remove the outer peripheral portion 5b that is adhered to the carrier plate 3 in a manner that properly separates the central portion 5a.

[0032] The workpiece 7, also referred to as a packaged panel or packaged wafer, includes: a wiring layer (RDL) (not shown) in contact with the central portion 5a of the temporary adhesive layer 5; a plurality of device chips 9 bonded to the wiring layer; and a molding resin layer 11 sealing each device chip 9. The workpiece 7 is configured, for example, in a disk shape similar to the carrier plate 3. Furthermore, the thickness of the workpiece 7 is, for example, 1.5 mm or less, typically 0.6 mm.

[0033] Furthermore, the first surface (front) 7a side of the workpiece 7 (the side opposite to the temporary adhesive layer 5) can be processed by methods such as grinding. Additionally, predetermined dividing lines are set in the area between adjacent device chips 9 within the workpiece 7. For example, the workpiece 7 can be cut along any predetermined dividing line, thereby dividing the workpiece 7 into multiple workpiece pieces, each containing one or more device chips 9.

[0034] Furthermore, if the workpiece 7 (or workpiece sheet) is cut along all the predetermined dividing lines, multiple packaged devices corresponding to each device chip 9 are obtained. However, there are no particular restrictions on the material, structure, size, etc. of the workpiece 7. For example, the workpiece 7 may sometimes be mainly composed of wiring layers and does not contain device chips 9 or molding resin layers 11, etc.

[0035] In the carrier plate removal method of this embodiment, the outer periphery of the first surface 3a side of the carrier plate 3 is first removed together with the outer periphery of the workpiece 7 and the outer periphery 5b of the temporary adhesive layer 5, forming a stepped difference portion on the outer periphery of the carrier plate 3 (step difference portion forming process).Figure 3 (A) is a cross-sectional view showing the case where the composite substrate 1 is held on the carrier plate 3 side. Figure 3 (B) is a cross-sectional view showing the case where a stepped difference is formed in the carrier plate 3.

[0036] When forming a stepped difference portion on the outer periphery of the carrier plate 3, use Figure 3 (A) and Figure 3 The cutting device 2 shown in (B) has a chuck stage 4 for holding the composite substrate 1. The chuck stage 4 includes, for example, a cylindrical frame 6 made of a metal material, such as stainless steel, and a holding plate 8 made of a porous material and disposed on the upper part of the frame 6.

[0037] The upper surface of the holding plate 8 serves as a holding surface 8a for attracting and holding the carrier plate 3 of the composite substrate 1. The lower surface of the holding plate 8 is connected to the attraction source 12 via a flow path 6a and a valve 10 disposed inside the frame 6. Therefore, if the valve 10 is opened, the negative pressure of the attraction source 12 can be applied to the holding surface 8a.

[0038] The chuck table 4 (frame 6) is connected to a rotary drive source (not shown) such as an electric motor, and rotates about a rotation axis that is substantially perpendicular to the holding surface 8a by the force generated by the rotary drive source. In addition, the chuck table 4 (frame 6) is supported by a machining feed mechanism (not shown) and moves in a machining feed direction that is substantially parallel to the holding surface 8a.

[0039] like Figure 3 As shown in (B), a cutting unit 14 is arranged above the chuck table 4. The cutting unit 14 has a spindle 16 that serves as a rotation axis substantially parallel to the holding surface 8a. An annular cutting tool 18, formed by dispersing abrasive grains in a binder, is mounted on one end of the spindle 16.

[0040] A rotary drive source (not shown) such as an electric motor is connected to the other end of the spindle 16. The cutting tool 18, mounted on one end of the spindle 16, rotates by the force generated by this rotary drive source. The cutting unit 14 is supported, for example, by a lifting mechanism (not shown) and an indexing feed mechanism (not shown), and moves in a vertical direction that is approximately perpendicular to the holding surface 8a and in an indexing feed direction that is approximately perpendicular to both the vertical direction and the machining feed direction.

[0041] When a stepped difference is formed on the outer periphery of the carrier plate 3, the carrier plate 3 of the composite substrate 1 is first held so that the workpiece 7 is exposed upwards. That is, as Figure 3After the second surface 3b of the carrier plate 3 is brought into contact with the holding surface 8a of the chuck table 4 as shown in (A) of FIG. 6, the valve 10 is opened to apply the negative pressure of the suction source 12 to the holding surface 8a. Thus, the carrier plate 3 of the composite substrate 1 is held by the chuck table 4, and the workpiece 7 is exposed upward.

[0042] Next, the cutting tool 18 is made to cut into the outer peripheral portion of the composite substrate 1, and the outer peripheral portion of the workpiece 7, the outer peripheral portion 5b of the temporary adhesive layer 5, and the outer peripheral portion on the first surface 3a side of the carrier plate 3 are removed. Specifically, as shown in (A) of FIG. 5, the relative positions of the chuck table 4 and the cutting unit 14 are adjusted so that the cutting tool 18 is made to cut into the outer peripheral portion of the composite substrate 1. Then, the chuck table 4 is rotated. Figure 3 (B) of FIG. 5 shows the state in which the cutting tool 18 is made to cut into the outer peripheral portion of the composite substrate 1. Then, the chuck table 4 is rotated.

[0043] In the present embodiment, the relative positions of the chuck table 4 and the cutting unit 14 are adjusted so that the lower end of the cutting tool 18 is positioned at a position lower than the first surface 3a and higher than the second surface 3b of the carrier plate 3. In the present embodiment, the amount of rotation of the chuck table 4 is set to one revolution or more.

[0044] Thus, the outer peripheral portion of the workpiece 7, the outer peripheral portion 5b of the temporary adhesive layer 5, and the outer peripheral portion on the first surface 3a side of the carrier plate 3 are removed along the entire circumference of the composite substrate 1, respectively. Further, the second surface 3b side of the carrier plate 3 is formed with a stepped portion 3c that protrudes laterally (outward in the radial direction of the carrier plate 3) from the first surface 3a side (see (A) of FIG. 6, (B) of FIG. 6, and the like). Figure 4 (A) of FIG. 6, Figure 4 (B) of FIG. 6, and the like).

[0045] Further, in the present embodiment, the stepped portion 3c is formed on the carrier plate 3 by the method in which the cutting tool 18 is made to cut, but the stepped portion 3c can also be formed by another method. For example, the stepped portion 3c can also be formed on the carrier plate 3 by laser ablation processing using a laser beam of a wavelength that is absorbed by the workpiece 7. In this case, instead of the cutting device 2 (cutting unit 14), a laser processing device (laser processing unit) capable of irradiating a laser beam of a wavelength that is absorbed by the carrier plate 3 or the like is used.

[0046] Figure 4 (A) of FIG. 6 is a plan view showing the state in which the stepped portion 3c is formed on the entire outer peripheral portion of the carrier plate 3, Figure 4 (B) of FIG. 6 is a cross-sectional view showing the state in which the stepped portion 3c is formed on the entire outer peripheral portion of the carrier plate 3. Further, in the present embodiment, the stepped portion 3c is formed on the entire outer peripheral portion of the carrier plate 3, but the stepped portion of the present application can be formed on only a part of the outer peripheral portion of the carrier plate.

[0047] The width of the stepped portion 3c (the width of the carrier plate 3 overlapping the cutting tool 18) is arbitrarily set, for example, within a range that does not affect the package device or the like cut out from the workpiece 7. The width of the stepped portion 3c is preferably set to be, for example, 0.2 mm or more and 5 mm or less when considering the easiness of removal of the carrier plate 3 or the like.

[0048] After the stepped portion 3c is formed in the outer peripheral portion of the carrier plate 3, a region of a portion (i.e., a region of a portion of the workpiece 7 adjacent to the outer peripheral portion of the workpiece 7 removed when the stepped portion 3c is formed) in contact with a new outer periphery of the workpiece 7 is further removed, and a starting point region (starting point region forming step) that becomes a starting point when the carrier plate 3 is peeled from the workpiece 7 is formed. Figure 5 is a plan view showing a state in which the starting point region 7b is formed in the workpiece 7.

[0049] When the starting point region 7b is formed in the workpiece 7, for example, the cutting device 2 described above is used. Specifically, first, the carrier plate 3 side is held by the chuck table 4 in a manner that the workpiece 7 side of the composite substrate 1 is exposed upward. Also, the chuck table 4 and the cutting unit 14 are relatively moved while the rotating cutting tool 18 is cut into the workpiece 7 (and the temporary adhesive layer 5).

[0050] Thus, the starting point region 7b that becomes a starting point when the carrier plate 3 is peeled from the workpiece 7 can be formed by further removing a region of a portion of the workpiece 7. In the present embodiment, as shown in Figure 5 the workpiece 7 is cut in a straight line at a position corresponding to a chord of a circle constituting the outline of the workpiece 7, and the starting point region 7b having a corner portion at both end portions is formed.

[0051] In this case, the force when the carrier plate 3 is peeled concentrates on the corner portion of the starting point region 7b, and thus the carrier plate 3 is easily peeled from the workpiece 7. That is, unlike the case where the starting point region 7b is not formed, the force when the carrier plate 3 is peeled is not dispersed in the curved (arc-shaped) outer periphery of the workpiece 7 and thus does not act properly.

[0052] In addition, in the present embodiment, the starting point region 7b is formed by the method of cutting the cutting tool 18 into the workpiece 7, but the starting point region 7b can also be formed by other methods. For example, the starting point region 7b can also be formed by laser ablation processing using a laser beam of a wavelength absorbed by the workpiece 7.

[0053] After the starting point region 7b is formed, the workpiece 7 of the composite substrate 1 is held from above (holding step). Figure 6 (A) of is a cross-sectional view showing a case where the workpiece 7 is held from above. When the workpiece 7 is held from above, the chuck table 4 is used. Figure 6The peeling device 22 shown in (A) and others. The peeling device 22 has a holding unit 24 for holding the workpiece 7 of the composite substrate 1 from above.

[0054] A holding surface 24a, having the same size as the first surface 7a of the workpiece 7, is formed at the lower part of the holding unit 24. An attraction source (not shown) is connected to this holding surface 24a via a flow path (not shown) and a valve (not shown). Therefore, if the valve is opened, a negative pressure from the attraction source is applied to the holding surface 24a. Furthermore, the holding unit 24 is supported by a lifting mechanism (not shown) and moves in the vertical direction.

[0055] When holding workpiece 7 from above, such as Figure 6 As shown in (A), for example, with the workpiece 7 positioned above the carrier plate 3, the holding surface 24a of the holding unit 24 is brought into contact with the first surface 7a of the workpiece 7. Furthermore, the valve is opened, causing a negative pressure from the suction source to act on the holding surface 24a. Thus, the workpiece 7 of the composite substrate 1 is held from above by the holding unit 24.

[0056] In this embodiment, the first surface 7a of the workpiece 7 is in direct contact with the holding surface 24a of the holding unit 24. However, a porous sheet or the like can also be sandwiched between the first surface 7a of the workpiece 7 and the holding surface 24a of the holding unit 24. This prevents damage or contamination of the workpiece 7 caused by contact with the holding surface 24a.

[0057] Furthermore, the end material removed from the workpiece 7 during the formation of the starting region 7b remains on the composite substrate 1. Therefore, when holding the workpiece 7 using the holding unit 24, it is sufficient to hold only the portion of the workpiece 7 other than the end material. Of course, the holding unit 24 can also be used to hold the entire workpiece 7, including the end material.

[0058] After holding the workpiece 7 from above, a downward force is applied to the stepped difference portion 3c, thereby peeling the carrier plate 3 off the workpiece 7 and removing it (carrier plate removal process). Figure 6 (B) is a cross-sectional view showing the application of a downward force to the stepped difference section 3c. Figure 6 (C) is a cross-sectional view showing the state in which the carrier plate 3 has been peeled off from the workpiece 7. The peeling device 22 is used while peeling the carrier plate 3 off the workpiece 7.

[0059] like Figure 6 As shown in (B), a rod-shaped pushing member 26 is disposed on the side of the holding unit 24 at a position corresponding to the stepped difference portion 3c of the composite substrate 1 held by the holding unit 24. The pushing member 26 is supported, for example, by a lifting mechanism (not shown) that is different from the lifting mechanism that moves the holding unit 24, and moves independently in the vertical direction relative to the holding unit 24.

[0060] When the carrier sheet 3 is removed from the workpiece 7, the holding unit 24 and the pressing member 26 are first moved upward together, and the composite substrate 1 held by the holding unit 24 is lifted. That is, the second surface 3b side of the carrier sheet 3 is exposed downward. Next, the pressing member 26 is moved downward while holding the position of the holding unit 24, and the lower end of the pressing member 26 is brought into contact with the stepped portion 3c. That is, the pressing member 26 applies a downward force to the stepped portion 3c of the carrier sheet 3.

[0061] As described above, the workpiece 7 of the composite substrate 1 is held from above by the holding unit 24. Therefore, when a downward force is applied to the stepped portion 3c of the carrier sheet 3 by the pressing member 26, the carrier sheet 3 is peeled off and falls from the workpiece 7 with the temporary adhesive layer 5 as a boundary. That is, the carrier sheet 3 moves in a direction away from the workpiece 7. In the present embodiment, the outer peripheral portion 5b of the temporary adhesive layer 5 adhered to the carrier sheet 3 is removed when the stepped portion 3c is formed, and thus the carrier sheet 3 can be easily peeled off and removed from the workpiece 7.

[0062] In addition, in the present embodiment, the starting region 7b having a corner portion is formed on the workpiece 7, and thus the force at the time of peeling off the carrier sheet 3 is concentrated on the corner portion of the starting region 7b. Thus, the carrier sheet 3 can be easily peeled off from the workpiece 7. In addition, in order to make the force at the time of peeling off the carrier sheet 3 act more strongly on the corner portion of the starting region 7b, it is sufficient to apply a downward force to the portion of the stepped portion 3c adjacent to the starting region 7b (the portion located on the outer side of the starting region 7b in the radial direction) by the pressing member 26. Thus, the carrier sheet 3 can be more easily peeled off from the workpiece 7.

[0063] As described above, in the removal method of the carrier sheet in the present embodiment, the outer peripheral portion of the workpiece 7, the outer peripheral portion 5b of the temporary adhesive layer 5, and the outer peripheral portion on the first surface (front surface) 3a side of the carrier sheet 3 are removed to form the stepped portion 3c in which the second surface 3b side of the carrier sheet 3 protrudes laterally more than the first surface 3a side of the carrier sheet 3, and a region of a portion in contact with the new outer periphery of the workpiece 7 (that is, a region of a portion of the workpiece 7 adjacent to the outer peripheral portion of the workpiece 7 removed when the stepped portion 3c is formed) is removed to form the starting region 7b that becomes a starting point at the time of peeling off the carrier sheet 3 from the workpiece 7.

[0064] Thus, the workpiece 7 is held from above by the holding unit 24 and a downward force is applied to the stepped portion 3c, and thus the carrier sheet 3 can be easily peeled off and removed from the workpiece 7 with the starting region 7b as a starting point. In addition, the gravitational force acting on the carrier sheet 3 is used together with the downward force applied to the stepped portion 3c, and thus a large force is not required when the carrier sheet 3 is removed from the workpiece 7.

[0065] In addition, the present application is not limited to the above-described embodiments, and various modifications can be made and implemented. For example, in the above-described embodiments, the step of forming the stepped portion 3c in the outer peripheral portion of the carrier sheet 3 is performed after the step of forming the starting point region 7b in the workpiece 7, but the step of forming the starting point region 7b in the workpiece 7 can be performed after the step of forming the stepped portion 3c in the outer peripheral portion of the carrier sheet 3. In this case, the region of a portion of the workpiece 7 adjacent to the outer peripheral portion of the workpiece 7 to be removed when the stepped portion 3c is formed is removed to form the starting point region 7b.

[0066] In addition, in the above-described embodiments, the starting point region 7b having a corner portion is formed by cutting the workpiece 7 in a straight line at a position corresponding to a chord of a circle constituting the outline of the workpiece 7, but the shape and the like of the starting point region of the present application can be modified within a range in which a force at the time of peeling the carrier sheet acts appropriately. Figure 7 FIG. 7 is a plan view showing a starting point region 7c formed using a carrier sheet removal method of a first modified example.

[0067] In addition, the steps and the like of the carrier sheet removal method of the first modified example are the same as those of the carrier sheet removal method of the above-described embodiments except for the steps and the like of forming the starting point region 7c. Therefore, hereinafter, the steps and the like of forming the starting point region 7c will mainly be described, and detailed description of other steps and the like will be omitted.

[0068] Figure 7 The starting point region 7c shown is formed, for example, by laser ablation processing using a laser beam of a wavelength absorbed by the workpiece 7. That is, the workpiece 7 is cut in such a manner that a region of a portion of the workpiece 7 adjacent to the outer peripheral portion of the workpiece 7 to be removed when the stepped portion 3c is formed (or the outer peripheral portion of the workpiece 7 to be removed when the stepped portion 3c is formed) is removed from the workpiece 7.

[0069] Thus, the region of a portion of the workpiece 7 can be removed to form the starting point region 7c that becomes a starting point at the time of peeling the carrier sheet 3 from the workpiece 7. In the first modified example, as shown in FIG. 7, the workpiece 7 is cut in such a manner that a semicircular region is removed from the workpiece 7 to form the starting point region 7c having a corner portion. In addition, in this first modified example, the starting point region 7c is formed by laser ablation processing using a laser beam, but the starting point region 7c can be formed by other methods. Figure 7

[0070] In addition, in the above-described embodiments, the starting point region 7b having a corner portion is formed by cutting the workpiece 7 in a straight line at a position corresponding to a chord of a circle constituting the outline of the workpiece 7, but the shape and the like of the starting point region of the present application can be modified within a range in which a force at the time of peeling the carrier sheet acts appropriately.

[0071] ​Further, the pushing member 26 of the above embodiment is configured to be able to move independently of the holding unit 24 in the vertical direction, but the pushing member 26 can move relatively to the holding unit 24 at least.

[0072] Therefore, for example, the pushing member 26 can be fixed to a housing (not shown) of the peeling device 22 or the like, and only the holding unit 24 can be moved, so that the pushing member 26 moves relatively to the holding unit 24. Further, in the above embodiment, one pushing member 26 is used, but a plurality of pushing members 26 can be used.

[0073] Further, when the carrier plate 3 is removed by peeling from the workpiece 7, the temporary adhesive layer 5 exposed between the carrier plate 3 and the workpiece 7 can be blown with fluid. Figure 8 (A) is a cross-sectional view showing a case where the carrier plate 3 is peeled from the workpiece 7 by the carrier plate removal method of the second modification.

[0074] Further, most of the carrier plate removal method of the second modification is the same as the carrier plate removal method of the above embodiment. Therefore, hereinafter, only the different points will be described, and the detailed description of the same parts will be omitted. As shown in (A) of the above embodiment, Figure 8 As shown in (A), a nozzle 32 is arranged on the side of the holding unit 24 of the peeling device 22 used in the second modification. A supply source (not shown) of fluid 34 is connected to the nozzle 32 via a flow path (not shown) and a valve (not shown) or the like.

[0075] After the fluid 34 is blown from the nozzle 32 to the temporary adhesive layer 5 exposed between the carrier plate 3 and the workpiece 7, a downward force is applied to the step difference portion 3c, or the fluid 34 is blown to the temporary adhesive layer 5 exposed between the carrier plate 3 and the workpiece 7 while a downward force is applied to the step difference portion 3c by the pushing member 26, so that the carrier plate 3 can be more easily peeled from the workpiece 7. As the fluid 34 blown between the carrier plate 3 and the workpiece 7, for example, air or water or the like can be used. However, the kind of the fluid 34 or the like is not particularly limited.

[0076] Further, when the carrier plate 3 is removed by peeling from the workpiece 7, the carrier plate 3 and the workpiece 7 can be sunk into a liquid. Figure 8 (B) is a cross-sectional view showing a case where the carrier plate 3 is peeled from the workpiece 7 by the carrier plate removal method of the third modification. Further, most of the carrier plate removal method of the third modification is the same as the carrier plate removal method of the above embodiment. Therefore, hereinafter, only the different points will be described, and the detailed description of the same parts will be omitted.

[0077] As shown in (A) of the above embodiment, Figure 8As shown in (B), a groove 42 capable of accommodating the size of the carrier sheet 3 and the workpiece 7 is provided below the holding unit 24 of the peeling device 22 used in this third modification. A liquid 44 such as water is stored in the groove 42.

[0078] When the carrier sheet 3 is peeled from the workpiece 7 by applying a downward force to the stepped portion 3c with the push member 26 in a state where the carrier sheet 3 and the workpiece 7 are sunk into the liquid 44 in the groove 42, the carrier sheet 3 peeled from the workpiece 7 falls in the liquid 44. As a result, compared to a case where the carrier sheet 3 falls in the air, the impact of the fall is reduced, and damage to the carrier sheet 3, vibration of the peeling device 22, and the like can be prevented.

[0079] In addition, a surfactant can be included in the liquid 44. As the surfactant included in the liquid 44, an anionic surfactant or a cationic surfactant that easily enters the temporary adhesive layer 5, or the like can be used. In this way, by including a surfactant that easily enters the temporary adhesive layer 5 in the liquid 44, the temporary adhesive layer 5 can be easily separated from the region where the surfactant has entered, and thus the carrier sheet 3 can be more easily peeled from the workpiece 7.

[0080] In addition, in the third modification, when a downward force is applied to the stepped portion 3c with the push member 26 after the carrier sheet 3 and the workpiece 7 are sunk into the liquid 44, the push member 26 can be given vibration such as ultrasonic waves. Specifically, while the push member 26 is given vibration such as ultrasonic waves, a downward force is applied to the stepped portion 3c with the push member 26. In this case, by the action of the vibration transmitted from the push member 26, the carrier sheet 3 can be more easily peeled from the workpiece 7.

[0081] Likewise, when a downward force is applied to the stepped portion 3c with the push member 26 after the carrier sheet 3 and the workpiece 7 are sunk into the liquid 44, the liquid 44 can be given vibration such as ultrasonic waves. Specifically, while the liquid 44 is given vibration such as ultrasonic waves, a downward force is applied to the stepped portion 3c with the push member 26. In this case, by the action of the vibration transmitted from the liquid 44, the carrier sheet 3 can be more easily peeled from the workpiece 7.

[0082] In addition, the second modification can be further combined with the third modification. That is, the fluid can be blown to the temporary adhesive layer 5 exposed between the carrier sheet 3 and the workpiece 7 before or after the carrier sheet 3 and the workpiece 7 are sunk into the liquid 44. In this case, the carrier sheet 3 can be more easily peeled from the workpiece 7.

[0083] In addition to the above, the configuration, method, and the like of the above-described embodiments can be appropriately changed and implemented without departing from the scope of the present application.

Claims

1. A method for removing a carrier plate, wherein the carrier plate is peeled off from the workpiece of a disc-shaped composite substrate on the front side of the carrier plate by means of a temporary adhesive layer, wherein, The method for removing the carrier plate includes the following steps: The step difference formation process removes the outer periphery of the workpiece, the outer periphery of the temporary adhesive layer, and the outer periphery of the front side of the carrier plate to form a step difference that protrudes laterally from the back side of the carrier plate compared to the front side of the carrier plate. The starting area forming process removes a portion of the workpiece that is adjacent to the outer periphery of the workpiece to form a starting area that becomes the starting point when the carrier plate is peeled off from the workpiece. In the holding process, after the stepped difference and the starting area are formed, the workpiece is held from above by a holding unit while it is positioned above the carrier plate. as well as In the carrier plate removal process, after the workpiece is held from above by the holding unit, the carrier plate is moved in a downward direction away from the workpiece by applying a downward force to the stepped difference section by the pushing member. Thus, the carrier plate is peeled off from the workpiece by the gravity acting on the carrier plate and the downward force applied to the stepped difference section.

2. The method for removing the carrier plate according to claim 1, wherein, In the carrier plate removal process, after blowing fluid onto the temporary adhesive layer exposed between the workpiece and the carrier plate, a downward force is applied to the stepped difference portion, or while blowing fluid onto the temporary adhesive layer exposed between the workpiece and the carrier plate, a downward force is applied to the stepped difference portion to peel the carrier plate off from the workpiece and remove it.

3. The method for removing the carrier plate according to claim 1, wherein, In the carrier plate removal process, while the workpiece and the carrier plate are submerged in the liquid, a downward force is applied to the stepped difference section.

4. The method for removing the carrier plate according to claim 3, wherein, The liquid contains surfactants.

5. The method for removing the carrier plate according to claim 2, wherein, In the carrier plate removal process, while the workpiece and the carrier plate are submerged in the liquid, a downward force is applied to the stepped difference section.

6. The method for removing the carrier plate according to claim 5, wherein, The liquid contains surfactants.

7. The method for removing the carrier plate according to any one of claims 3 to 6, wherein, In the carrier plate removal process, while the workpiece and the carrier plate are immersed in the liquid, a downward force is applied to the stepped section while the pushing member is vibrated.

8. The method for removing the carrier plate according to any one of claims 3 to 6, wherein, In the carrier plate removal process, while the workpiece and the carrier plate are immersed in the liquid, a downward force is applied to the stepped difference section while the liquid is vibrated.

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