Manufacturing method for molded product

Abstract

To provide a manufacturing method for a molded product that can provide a molded product in a desired shape in a short time.SOLUTION: A manufacturing method for a molded product includes: a shield tunnel forming step 1 of forming a shield tunnel including a pore extending from a first surface side to a predetermined depth in a thickness direction and a modified region surrounding the pore, by positioning a condensing region of a first laser beam, inside a work-piece and emitting the laser beam along a desired shape; a separating layer forming step 2 of forming a separating layer including a modified part that is parallel to a first surface and a crack extending from the modified part, by positioning a condensing point of a second laser beam, in a depth corresponding to a thickness of a molded product whose first surface should be manufactured first and also emitting the second laser beam while relatively moving the condensing point and the work-piece; a separating step 3 of separating the work-piece into a first work-piece and a second work-piece, with the separating layer as a starting point; and a driving step 5 of dividing the molded product by applying predetermined processing to the first work-piece.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for producing a molded article. [Background technology]

[0002] In recent years, with the diversification of mobile device designs, non-rectangular and curved display panels have appeared. The shapes of the materials used for housings are also diversifying in line with the diversification of display panel shapes. There is also a demand for cutting materials into a wide variety of shapes, such as cover glass to protect cameras and optical components installed in smartphones.

[0003] However, many of the materials used in the above applications are known to be hard, brittle, and difficult to process, such as glass, quartz, and SiC (silicon carbide), and it is not easy to process them into the desired shape. Therefore, a method has been proposed in which a laser beam is irradiated onto such materials to form a modified region called a shield tunnel, which has a pore and an altered region surrounding the pore, and thereby molded products of the desired shape are produced (see Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-132476 [Patent Document 2] Japanese Patent Publication No. 2020-110830 Summary of the Invention [Problem to be solved by the invention]

[0005] The above method can produce molded products with fine shapes, but has the problem of being time-consuming because it requires irradiating each substrate with a laser beam to mold it into the desired shape.

[0006] The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for producing a molded article, which can obtain a molded article of a desired shape in a short time. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, the method for manufacturing a molded product of the present invention is a method for manufacturing a molded product in a desired shape from a workpiece having a first surface and a second surface opposite to the first surface, and includes a shield tunnel forming step of positioning a focal point of a first laser beam having a wavelength that is transparent to the workpiece inside the workpiece and irradiating the first laser beam along the desired shape to form a shield tunnel along the desired shape, the shield tunnel including a pore extending from the first surface side of the workpiece to a predetermined depth in the thickness direction of the workpiece and a modified region surrounding the pore; and a shield tunnel forming step of positioning a focal point of a second laser beam having a wavelength that is transparent to the workpiece inside the workpiece and irradiating the second laser beam along the desired shape to form a shield tunnel along the desired shape, the shield tunnel including a pore extending from the first surface side of the workpiece to a predetermined depth in the thickness direction of the workpiece and a modified region surrounding the pore. and a separation layer forming step of forming a separation layer including a modified portion parallel to the first surface and a crack extending from the modified portion by positioning the focal point at a depth corresponding to the first surface and relatively moving the focal point and the workpiece to irradiate the workpiece with the second laser beam; a separation step of separating the workpiece into a first workpiece having the first surface and a second workpiece having the second surface, starting from the separation layer, after performing the shield tunnel forming step and the separation layer forming step; and a division step of dividing a molded product from the first workpiece along the shield tunnel formed along the desired shape by subjecting the first workpiece to a predetermined treatment.

[0008] In the method for producing a molded article of the present invention, the separation layer forming step is preferably carried out after the shield tunnel forming step is carried out.

[0009] In addition, it is preferable that the method for manufacturing a molded product of the present invention further includes a planarization step of flattening the separation surfaces of the first workpiece and the second workpiece separated in the separation step by grinding or polishing the separation surfaces.

[0010] In addition, in the method for manufacturing a molded product of the present invention, the dividing step may involve grinding or polishing the dividing surface of the first workpiece to flatten the dividing surface, and applying an external force to the first workpiece to divide the molded product from the first workpiece.

[0011] In addition, in the method for manufacturing a molded product of the present invention, the dividing step may involve applying an external force to the first workpiece to divide the molded product from the first workpiece along the shield tunnel.

[0012] In addition, in the method for manufacturing a molded product of the present invention, the dividing step may involve etching the first workpiece with an etching agent to divide the molded product from the first workpiece along the shield tunnel.

[0013] Furthermore, in the method for manufacturing a molded product of the present invention, the shield tunnel forming step preferably includes a parting auxiliary line setting step of setting a parting auxiliary line between the outer peripheral edge of the workpiece and the molded product, and a parting auxiliary starting point forming step of positioning a focusing region of a third laser beam having a wavelength that is transparent to the workpiece inside the workpiece and irradiating the third laser beam along the parting auxiliary line, thereby forming a shield tunnel along the parting auxiliary line inside the workpiece, the shield tunnel including a pore and a modified region surrounding the pore.

[0014] Furthermore, in the method for manufacturing a molded product of the present invention, the shield tunnel formation step may involve controlling the intensity distribution of the first laser beam irradiated inside the workpiece, and irradiating the workpiece with the first laser beam having the controlled intensity distribution to form a shield tunnel inside the workpiece that includes a pore and a modified region surrounding the pore, and forming a crack parallel to the first surface at a depth corresponding to the thickness of the molded product to be manufactured.

[0015] Furthermore, in the method for producing a molded product of the present invention, the shield tunnel forming step includes: a first shield tunnel forming step of positioning the focusing region of the first laser beam in a first region inside the workpiece and irradiating it along the desired shape, thereby forming a first shield tunnel along the desired shape, the first shield tunnel including a pore extending along the thickness direction of the workpiece and a modified region surrounding the pore; and a second shield tunnel forming step of positioning the focusing region of the first laser beam in a second region inside the workpiece that is positioned differently in the thickness direction from the first region and irradiating it along the desired shape, thereby forming a second shield tunnel along the desired shape, the second shield tunnel including a pore extending along the thickness direction of the workpiece and a modified region surrounding the pore. At a depth corresponding to the thickness of the molded product to be produced, the first shield tunnel and the second shield tunnel may be set to overlap by a predetermined amount or more in the thickness direction, thereby forming a crack parallel to the first surface at a depth corresponding to the thickness of the molded product to be produced. [Effects of the Invention]

[0016] The present invention makes it possible to obtain a molded product of a desired shape in a short time. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view of a workpiece to be processed in a method for manufacturing a molded product according to an embodiment. [Figure 2] FIG. 2 is a side view of the workpiece shown in FIG. [Figure 3]FIG. 3 is a flowchart showing the flow of the method for manufacturing a molded product according to the embodiment. [Figure 4] FIG. 4 is a perspective view showing one state of the shield tunnel forming step shown in FIG. [Figure 5] FIG. 5 is an enlarged cross-sectional view of a portion of the workpiece after FIG. [Figure 6] FIG. 6 is a perspective view that schematically shows the structure of a shield tunnel. [Figure 7] FIG. 7 is a cross-sectional view illustrating a procedure for forming a multi-layer shield tunnel. [Figure 8] FIG. 8 is a cross-sectional view showing an example of an interlayer structure of a multi-layer shield tunnel. [Figure 9] FIG. 9 is a cross-sectional view showing another example of an interlayer structure of a multi-layer shield tunnel. [Figure 10] FIG. 10 is a top view of the workpiece for explaining the auxiliary dividing line setting step and the auxiliary dividing start point forming step. [Figure 11] FIG. 11 is a perspective view showing one state of the separation layer forming step shown in FIG. [Figure 12] FIG. 12 is a side view, partly in section, showing one state of the separation layer forming step shown in FIG. [Figure 13] FIG. 13 is a top view of the workpiece in FIGS. [Figure 14] FIG. 14 is a side view showing one state of the separation step shown in FIG. [Figure 15] FIG. 15 is a side view showing one state of the separation step shown in FIG. [Figure 16] FIG. 16 is a side view, partly in section, showing one state of the planarizing step shown in FIG. [Figure 17] FIG. 17 is a side view, partly in section, showing one state of the planarizing step shown in FIG. [Figure 18] FIG. 18 is a side view, partly in section, showing one state of the first example of the dividing step shown in FIG. [Figure 19]FIG. 19 is a side view, partly in section, showing one state of the first example of the dividing step shown in FIG. [Figure 20] 20 is a side view, partly in section, showing a state of the second example of the dividing step shown in FIG. 3. FIG. [Figure 21] FIG. 21 is a side view, partly in section, showing one state of the second example of the dividing step shown in FIG. [Figure 22] FIG. 22 is a cross-sectional view of a workpiece for illustrating the shield tunnel forming step according to the first modified example. [Figure 23] FIG. 23 is a flowchart showing the flow of the shield tunnel forming step according to the second modification. [Figure 24] FIG. 24 is a cross-sectional view of a workpiece for illustrating the shield tunnel forming step according to the second modified example. DETAILED DESCRIPTION OF THE INVENTION

[0018] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the configuration can be made within the scope of the gist of the present invention.

[0019] [Embodiment] A method for producing a molded product 21 according to an embodiment of the present invention will be described with reference to the drawings. The method for producing a molded product 21 according to the embodiment is a method for obtaining a molded product 21 having a desired shape from a workpiece 10.

[0020] (Workpiece) First, the configuration of a workpiece 10 to be processed in a manufacturing method for a molded product 21 according to an embodiment of the present invention will be described. Fig. 1 is a perspective view of the workpiece 10 to be processed in a manufacturing method for a molded product 21 according to an embodiment. Fig. 2 is a side view of the workpiece 10 shown in Fig. 1.

[0021] 1 and 2 is an ingot made of silicon carbide (SiC), silicon (Si), lithium tantalate (LT), gallium nitride (GaN), gallium oxide (GaO), or the like, and formed into a cylindrical shape as a whole. In this embodiment, the thickness of the workpiece 10 is 350 μm. The workpiece 10 has a first surface 11, a second surface 12, a peripheral surface 13, a first orientation flat 14, and a second orientation flat 15.

[0022] The first surface 11 is circular and is one end surface of the cylindrical workpiece 10. The second surface 12 is circular and is the end surface of the cylindrical workpiece 10 opposite to the first surface 11. The second surface 12 corresponds to the bottom surface of the workpiece 10. The peripheral surface 13 is a surface that connects the outer edge of the first surface 11 and the outer edge of the second surface 12.

[0023] The first orientation flat 14 is a flat surface formed on a portion of the peripheral surface 13 to indicate the crystal orientation of the workpiece 10. The second orientation flat 15 is a flat surface formed on a portion of the peripheral surface 13 to indicate the crystal orientation of the workpiece 10. The second orientation flat 15 is perpendicular to the first orientation flat 14. The length of the first orientation flat 14 is longer than the length of the second orientation flat 15.

[0024] The workpiece 10 also has a c-axis 18 inclined at an off angle 20 in an inclination direction 17 toward the second orientation flat 15 with respect to a normal 16 to the first surface 11, and a c-plane 19 perpendicular to the c-axis 18. The inclination direction 17 of the c-axis 18 from the normal 16 is perpendicular to the extension direction of the second orientation flat 15 and is parallel to the first orientation flat 14. The c-plane 19 is inclined at the off angle 20 with respect to the first surface 11 of the workpiece 10.

[0025] Countless c-planes 19 are set in the workpiece 10 at the molecular level of the workpiece 10. In the embodiment, the workpiece 10 has an off-angle 20 set to 1°, 4°, or 6°, but in the present invention, the workpiece 10 may be manufactured with the off-angle 20 set freely within the range of 1° to 6°, for example. After the first surface 11 of the workpiece 10 is ground by a grinding device, the workpiece 10 is polished by a polishing device to form the first surface 11 into a mirror finish.

[0026] (Method of manufacturing molded product 21) Next, a method for manufacturing a molded article 21 according to an embodiment of the present invention will be described. Fig. 3 is a flowchart showing the flow of the method for manufacturing a molded article 21 according to an embodiment. The method for manufacturing a molded article 21 includes a shield tunnel forming step 1, a separation layer forming step 2, a separation step 3, a flattening step 4, and a division step 5.

[0027] <Shield tunnel formation step 1> FIG. 4 is a perspective view showing one state of the shield tunnel forming step 1 shown in FIG. 3. FIG. 5 is an enlarged cross-sectional view showing a portion of the workpiece 10 after FIG. 4. FIG. 6 is a perspective view showing a schematic structure of the shield tunnel 30. The shield tunnel forming step 1 is a step of forming the shield tunnel 30 along a desired shape, the shield tunnel 30 including a pore 31 extending from the first surface 11 side of the workpiece 10 to a predetermined depth in the thickness direction of the workpiece 10 and a modified region 32 surrounding the pore 31. The desired shape is the shape of the molded product 21 to be manufactured.

[0028] In the shield tunnel forming step 1 of the embodiment, a shield tunnel 30 is formed in a workpiece 10 by a laser processing apparatus 100 shown in Fig. 4. The laser processing apparatus 100 includes a holding table 110, a laser beam irradiation unit 120, an imaging unit 130, and a moving unit (not shown) that moves the holding table 110 and the laser beam irradiation unit 120 relative to each other.

[0029] The holding table 110 suction-holds the workpiece 10 on a holding surface 111. The holding surface 111 is a disk-shaped member made of porous ceramic or the like, and is connected to a vacuum suction source, for example, via a vacuum suction path. The laser beam irradiation unit 120 includes, for example, an oscillator that emits a laser beam, a condenser that focuses the laser beam toward the workpiece 10 held on the holding table 110, and various optical components that guide the laser beam from the oscillator to the condenser.

[0030] In shield tunnel forming step 1, first, the second surface 12 side of the workpiece 10 is suction-held on the holding surface 111 of the holding table 110. Next, the workpiece 10 is aligned with the condenser of the laser beam irradiation unit 120. Specifically, the holding table 110 is moved to the processing area below the laser beam irradiation unit 120 by a moving unit (not shown).

[0031] Next, the workpiece 10 is photographed by the imaging unit 130, and alignment is performed to align a predetermined processing position where the shield tunnel 30 is to be formed with the irradiation portion of the laser beam irradiation unit 120. After the irradiation portion of the laser beam irradiation unit 120 is vertically opposed to the first surface 11 of the workpiece 10, the focused region 122 of the first laser beam 121 is positioned inside the workpiece 10. The first laser beam 121 is a laser beam with a wavelength that is transparent to the workpiece 10.

[0032] In the shield tunnel forming step 1, the first pulsed laser beam 121 is then irradiated into the inside of the workpiece 10 while the holding table 110 and the laser beam irradiation unit 120 are moved relative to each other so that the first laser beam 121 is irradiated along a desired shape. In the embodiment, the processing conditions for the first laser beam 121 are a wavelength of 1064 nm, an output of 0.25 W, a repetition frequency of 1 kHz, a feed rate of 25 mm / s, and the number of passes is 7.

[0033] The workpiece 10 and the light-focusing region 122 positioned inside the workpiece 10 are moved relative to each other, and the first laser beam 121 is irradiated along a desired shape, thereby forming shield tunnels 30 that extend from the first surface 11 side of the workpiece 10 to a predetermined depth in the thickness direction of the workpiece 10. The shield tunnels 30 are formed along the desired shape at predetermined intervals by irradiating the pulsed first laser beam 121.

[0034] In this embodiment, the desired shape is a plurality of circles, as shown in Fig. 4. That is, the molded article 21 to be produced is a disk shape, and a plurality of molded articles 21 are produced in the horizontal direction.

[0035] 5, the shield tunnel 30 is preferably formed from the first surface 11 to the second surface 12, but there may be some areas where the shield tunnel 30 is not formed, for example, at the top, bottom, or center. The shield tunnel 30 is formed to a depth at least equal to or greater than the thickness 22 (see FIG. 17) of the molded product 21 to be manufactured, and is preferably formed to a depth at least twice the thickness 22 of the molded product 21 to be manufactured.

[0036] 6, the shield tunnel 30 has a pore 31 extending from the first surface 11 to the second surface 12 of the workpiece 10, and a cylindrical modified region 32 surrounding the pore 31. The modified region 32 is an amorphous region. The inner diameter 36 of the pore 31 is approximately 1 μm, the outer diameter 37 of the modified region 32 is approximately 5 μm, and the distance between adjacent modified regions 32 is approximately 10 μm.

[0037] As described above, the processing conditions of the embodiment involve seven passes. That is, multiple layers of shield tunnels 30 are formed. Here, the procedure for forming the multiple layers of shield tunnels 30 will be described. FIG. 7 is a cross-sectional view illustrating the procedure for forming the multiple layers of shield tunnels 30. FIG. 8 is a cross-sectional view showing an example of the interlayer structure of multiple layers of shield tunnels 30. FIG. 9 is a cross-sectional view showing another example of the interlayer structure of multiple layers of shield tunnels 30. In the following explanation, the number of passes will be omitted and a case where processing is performed in three passes will be described.

[0038] When the first laser beam 121 is irradiated from the first surface 11 side as in the embodiment, first, as shown in Fig. 7, a first shield tunnel 30-1 is formed in the first pass from the inside of the workpiece 10 to the second surface 12. Next, a second shield tunnel 30-2 is formed in the inside of the workpiece 10 on the first surface 11 side of the first shield tunnel 30-1. Then, a third shield tunnel 30-3 is formed in the third pass from the first surface 11 to the inside of the workpiece 10 on the first surface 11 side of the second shield tunnel 30-2.

[0039] In this case, the first shield tunnel 30-1 and the second shield tunnel 30-2 may be spaced apart as shown in Fig. 8, or may partially overlap as shown in Fig. 9. Similarly, the second shield tunnel 30-2 and the third shield tunnel 30-3 may be spaced apart or may partially overlap.

[0040] <Steps for setting auxiliary division lines and steps for forming auxiliary division starting points> The shield tunnel forming step 1 preferably includes a parting auxiliary line setting step and a parting auxiliary start point forming step. Fig. 10 is a top view of the workpiece 10 for explaining the parting auxiliary line setting step and the parting auxiliary start point forming step. The parting auxiliary line setting step is a step of setting a parting auxiliary line 34 between the outer periphery of the workpiece 10 and the parting line 33.

[0041] The division line 33 corresponds to the outline of the molded product 21 and corresponds to the boundary line along which the molded product 21 to be manufactured is divided from the first workpiece 10-1 (see Figures 18 and 19, etc., described later). The division auxiliary line 34 may be set between a predetermined position on the outer periphery of the workpiece 10 and a different position without passing through the division line 33. The division auxiliary line 34 may be connected to the division line 33, but it is preferable that it be slightly spaced apart.

[0042] The auxiliary dividing starting point forming step is a step of forming a shield tunnel 30 including a pore 31 and a modified region 32 surrounding the pore 31 inside the workpiece 10 along an auxiliary dividing line 34. The procedure of the auxiliary dividing starting point forming step is the same as the procedure of forming the shield tunnel 30 along the shape of the molded product 21. The auxiliary dividing starting point forming step may be performed as part of the shield tunnel forming step 1 as in the embodiment, or may be performed separately before or after the shield tunnel forming step 1.

[0043] When forming the shield tunnel 30 along the shape of the molded article 21, a focused region 122 of a first laser beam 121 having a wavelength that is transparent to the workpiece 10 is positioned inside the workpiece 10, and the first laser beam 121 is irradiated along the dividing line 33, thereby forming the shield tunnel 30 inside the workpiece 10 along the dividing line 33. In contrast, in the dividing auxiliary starter forming step, a focused region of a third laser beam having a wavelength that is transparent to the workpiece 10 is positioned inside the workpiece 10, and the third laser beam is irradiated along the dividing auxiliary line 34, thereby forming the shield tunnel 30 inside the workpiece 10 along the dividing auxiliary line 34. Because the dividing auxiliary starter forming step divides the region other than the region that will become the molded article 21 into multiple regions, the molded article 21 can be divided by expanding in the dividing step 5 described below.

[0044] The processing conditions for the third laser beam may be the same as or different from the processing conditions for the first laser beam 121. Furthermore, when the step of forming an auxiliary starting point for division is separately performed before or after the step of forming a shield tunnel 1, the laser processing device used in the step of forming an auxiliary starting point for division may be the same as or different from the laser processing device 100 used in the step of forming a shield tunnel 1.

[0045] <Separation layer formation step 2> Figure 11 is a perspective view showing one state of separation layer formation step 2 shown in Figure 3. Figure 12 is a side view, partially in cross section, showing one state of separation layer formation step 2 shown in Figure 3. Figure 13 is a top view of workpiece 10 in Figures 11 and 12. Separation layer formation step 2 is a step of forming separation layer 40 including modified portions 41 parallel to first surface 11 and cracks 42 extending from modified portions 41. Separation layer formation step 2 is preferably performed after shield tunnel formation step 1 is performed.

[0046] In the separation layer forming step 2 of the embodiment, the separation layer 40 is formed on the workpiece 10 by a laser processing apparatus 100 shown in Fig. 11. The laser processing apparatus 100 used in the separation layer forming step 2 may be the same as or a different apparatus from the laser processing apparatus 100 used in the shield tunnel forming step 1.

[0047] In separation layer formation step 2, first, the second surface 12 side of the workpiece 10 is suction-held on the holding surface 111 of the holding table 110. Next, the workpiece 10 is aligned with the condenser of the laser beam irradiation unit 120. Specifically, the holding table 110 is moved to the processing area below the laser beam irradiation unit 120 by a moving unit (not shown). Note that if the same laser processing apparatus 100 used in shield tunnel formation step 1 is used, the above procedure can be omitted.

[0048] In separation layer formation step 2, the second orientation flat 15 of the workpiece 10 is adjusted to be parallel to the processing feed direction (X-axis direction). Next, the focal point 124 of the second laser beam 123 is positioned at a depth corresponding to the thickness 22 (see FIG. 12) of the molded product 21 to be produced from the first surface 11 side of the workpiece 10. The second laser beam 123 is a laser beam with a wavelength that is transparent to the workpiece 10.

[0049] In separation layer forming step 2, the condenser of laser beam irradiation unit 120 and holding table 110 are then moved relatively. That is, the focal point 124 and workpiece 10 are moved relatively to irradiate second laser beam 123 onto workpiece 10. In this embodiment, the processing conditions for second laser beam 123 are a wavelength of 1064 nm, an output of 1.5 W, a repetition frequency of 120 kHz, a feed rate of 785 mm / s, and an index of 250 to 400 μm.

[0050] A focal point 124 positioned at a depth corresponding to the thickness 22 of the molded article 21 to be produced from the first surface 11 side of the workpiece 10 and the workpiece 10 are moved relative to each other, and a second laser beam 123 is irradiated along a direction parallel to the first surface 11, thereby forming a modified region 41 along a direction parallel to the first surface 11. Then, a crack 42 extending from the modified region 41 along the c-plane 19 is formed. In the embodiment, the crack 42 extends in the indexing feed direction (Y-axis direction). In this way, in the separation layer formation step 2, a separation layer 40 is formed that includes the modified region 41 and the crack 42 formed from the modified region 41 along the c-plane 19.

[0051] <Separation step 3> 14 and 15 are side views showing one state of the separation step 3 shown in Fig. 3. The separation step 3 is performed after the shield tunnel formation step 1 and the separation layer formation step 2. The separation step 3 is a step of separating the workpiece 10 into a first workpiece 10-1 having a first surface 11 and a second workpiece 10-2 having a second surface 12, starting from the separation layer 40.

[0052] In separation step 3 of the embodiment, the workpiece 10 is separated into a first workpiece 10-1 and a second workpiece 10-2 by a separation device 200 shown in Figures 14 and 15. The separation device 200 includes a holding table 210, a separation unit 220, and a moving unit (not shown) that moves the holding table 210 and the separation unit 220 relative to each other.

[0053] The holding table 210 suction-holds the second surface 12 of the workpiece 10 with a holding surface 211. The holding surface 111 is disc-shaped and made of porous ceramic or the like, and is connected to a vacuum suction source via a vacuum suction path, for example. The peeling unit 220 suction-holds the first surface 11 of the workpiece 10 with a holding surface 221 that faces the holding surface 211 of the holding table 210. The holding surface 211 is disc-shaped and made of porous ceramic or the like, and is connected to a vacuum suction source via a vacuum suction path, for example. The peeling unit 220 can be moved toward and away from the holding table 210 by a moving unit (not shown).

[0054] 14, first, the second surface 12 of the workpiece 10 is suction-held by the holding surface 211 of the holding table 210. Next, in the separation step 3, the peeling unit 220 is moved close to the holding table 210, and the first surface 11 of the workpiece 10 is suction-held by the holding surface 221.

[0055] 15, the peeling unit 220 is moved away from the holding table 210. As a result, the workpiece 10, which has been pulled vertically, is separated at the separation layer 40 as an interface into a first workpiece 10-1 having a first surface 11 and a second workpiece 10-2 having a second surface 12.

[0056] <Flattening step 4> 16 and 17 are side views, partially in cross section, showing one state of planarization step 4 shown in Fig. 3. Planarization step 4 is a step in which separation surface 23 of first workpiece 10-1 and separation surface 24 of second workpiece 10-2 separated in separation step 3 are ground or polished to planarize separation surfaces 23, 24.

[0057] In the planarization step 4 of the embodiment, the separation surface 23 of the first workpiece 10-1 is ground and planarized by a grinding apparatus 300 shown in Figures 16 and 17. The grinding apparatus 300 includes a holding table 310, a grinding unit 320, a grinding fluid supply unit (not shown), and a moving unit (not shown) that moves the holding table 310 and the grinding unit 320 relative to each other.

[0058] Holding table 310 suction-holds first surface 11 of first workpiece 10-1 with holding surface 311. Holding surface 311 is disk-shaped and made of porous ceramic or the like, and is connected to a vacuum suction source via a vacuum suction path, for example. Grinding unit 320 has spindle 321, which is a rotating shaft member, wheel base 322 attached to the lower end of spindle 321, and grinding wheel 323 attached to the lower surface of wheel base 322. Spindle 321 and wheel base 322 rotate on a rotation axis parallel to the axis of holding table 310.

[0059] In the flattening step 4, first, the first surface 11 of the first workpiece 10-1 is suction-held on the holding surface 311 of the holding table 310. Next, while the holding table 310 is rotated about its axis, the wheel base 322 is rotated about its axis via the spindle 321. A grinding fluid supply unit (not shown) supplies grinding fluid to the processing point, and the grinding wheel 323 of the wheel base 322 is moved toward the holding table 310 at a predetermined feed rate. This causes the grinding wheel 323 to grind the separation surface 23 of the first workpiece 10-1, thinning it to a predetermined thickness 22 shown in FIG. 17 . The predetermined thickness 22 is the thickness 22 of the molded product 21 to be manufactured.

[0060] Although the above describes the case where separation surface 23 of first workpiece 10-1 is ground, the same procedure can be used to grind separation surface 24 of second workpiece 10-2. In this case, the first workpiece 10-1 is replaced with second workpiece 10-2, separation surface 23 is replaced with separation surface 24, and first surface 11 is replaced with second surface 12.

[0061] <Split Step 5> 18 and 19 are side views, partially in cross section, showing one state of a first example of dividing step 5 shown in Fig. 3. Dividing step 5 is a step in which a predetermined process is performed on first workpiece 10-1, thereby dividing molded product 21 from first workpiece 10-1 along shield tunnel 30 formed along the desired shape.

[0062] In the dividing step 5 of the first example, an expansion device 400 shown in Figures 18 and 19 applies an external force to the first workpiece 10-1 to divide the molded product 21 from the first workpiece 10-1 along the shield tunnel 30. The expansion device 400 includes a holding table 410, a clamping member 420, and a lifting unit 430.

[0063] The holding table 410 suction-holds the first surface 11 of the first workpiece 10-1 with a holding surface 411. The holding surface 411 is disk-shaped and made of porous ceramic or the like, and is connected to a vacuum suction source, for example, via a vacuum suction path. A cylindrical abutment member 412 is provided around the periphery of the holding table 410, and is coaxial with the outer periphery of the holding table 410. A roller member 413 is rotatably provided on the upper end of the abutment member 412, on the same plane as or slightly above the holding surface 411 of the holding table 410.

[0064] In the dividing step 5 of the first example, first, an expanding tape 51 is adhered to the ground surface 25 of the first workpiece 10-1 that was ground or polished in the flattening step 4 and to an annular frame 50. The frame 50 is formed of metal or resin and is an annular plate having an opening larger than the outer diameter of the first workpiece 10-1. The expanding tape 51 is, for example, in the form of a sheet including a base layer made of an expandable synthetic resin and an adhesive layer laminated on the base layer and made of an expandable and adhesive synthetic resin.

[0065] The expanding tape 51 is, for example, attached to the first surface 11 of the first workpiece 10-1 and the annular frame 50, and then cut to a shape and size that covers the opening of the frame 50. The first workpiece 10-1 is positioned at a predetermined position in the opening of the frame 50, and the first surface 11 side is attached to the expanding tape 51, thereby fixing the first workpiece 10-1 to the frame 50 and the expanding tape 51.

[0066] 18, in dividing step 5, the first surface 11 of the first workpiece 10-1 is then placed on the holding surface 411 of the holding table 410 via the expanding tape 51, and the outer periphery of the frame 50 is fixed with the clamp members 420. At this time, the roller members 413 abut against the expanding tape 51 between the inner edge of the frame 50 and the outer edge of the first workpiece 10-1.

[0067] 19 , in dividing step 5, next, the holding table 410 and the abutting member 412 are raised together by the lifting unit 430. At this time, since the outer periphery of the expanding tape 51 is fixed by the clamping member 420 via the frame 50, the portion between the inner edge of the frame 50 and the outer edge of the first workpiece 10-1 is expanded in the planar direction. Furthermore, roller members 413 provided at the upper end of the abutting member 412 reduce friction with the expanding tape 51.

[0068] In the dividing step 5, as a result of the expansion of the expanding tape 51, a radial tensile force acts on the expanding tape 51. When the radial tensile force acts on the expanding tape 51, the first workpiece 10-1 to which the expanding tape 51 is attached is divided with the shield tunnel 30 as the fracture starting point, and the molded article 21 is divided into individual pieces, as shown in Figures 18 and 19 .

[0069] 20 and 21 are side views, partially in cross section, showing one state of a second example of dividing step 5 shown in Fig. 3. In dividing step 5 of the second example, first workpiece 10-1 is etched with etching solution 520 to divide molded product 21 from first workpiece 10-1 along shield tunnel 30.

[0070] In dividing step 5 of the second example, as shown in Figures 20 and 21, first workpiece 10-1 is immersed for a predetermined time inside a liquid tank 500 that stores etching solution 520, thereby breaking first workpiece 10-1 along shield tunnel 30 and dividing molded article 21 into individual pieces. At this time, it is preferable that the first surface 11 side of first workpiece 10-1 is placed on a loading net 510 that is provided at a predetermined height from the bottom surface of liquid tank 500. As etching solution 520 corrodes first workpiece 10-1 from the first surface 11 side and the grinding surface 25 side along shield tunnel 30, first workpiece 10-1 corrodes along shield tunnel 30 and breaks.

[0071] The dividing step 5 is not limited to the method shown in the first and second examples, and may be performed simultaneously with the planarizing step 4, for example. That is, the dividing step 5 may involve grinding or polishing the separation surface 23 of the first workpiece 10-1 to planarize the separation surface 23, and applying an external force to the first workpiece 10-1 to divide the molded article 21 from the first workpiece 10-1. In this case, the molded article 21 is divided into individual pieces by a grinding stress acting via the grinding wheel 323, with the shield tunnel 30 serving as the fracture starting point.

[0072] 19 and 20, it is necessary to form the shield tunnel 30 along the dividing assist line 34 in the shield tunnel forming step 1. When the dividing step 5 is performed by using an etching solution or grinding stress as shown in FIGS. 21 and 22, it is not necessarily necessary to perform the dividing assist starting point forming step.

[0073] When dividing step 5 is completed, all the steps in the flowchart shown in FIG. 3 are completed. Thereafter, the steps in the flowchart shown in FIG. 3 are repeated until a predetermined number of molded products 21 are produced from the workpiece 10. If shield tunnels 30 corresponding to the thickness of the molded products 21 to be produced have already been formed, shield tunnel forming step 1 is omitted, and the steps from separation layer forming step 2 to dividing step 5 are repeated. The second workpiece 10-2 separated in separating step 3 is treated as the next workpiece 10, and the surface obtained after the separation surface 24 has been ground in flattening step 4 is treated as the first surface 11. After the first workpiece 10-1 is separated in separating step 3, while flattening step 4 and dividing step 5 are being performed on the first workpiece 10-1, the second workpiece 10-2 may be used as a new workpiece 10 and the separation layer forming step 2 and shield tunnel forming step 1 may be performed in parallel.

[0074] The holding tables 110, 210, and 310 may be shared at least in successive steps. For example, the workpiece 10 on which the shield tunnel 30 and the separation layer 40 have been formed by the laser beam irradiation unit 120 may be transported on the holding table 110 to a position facing the peeling unit 220. Furthermore, the second workpiece 10-2 from which the first workpiece 10-1 has been separated by the peeling unit 220 may be transported on the holding table 210 to a position facing the grinding unit 320.

[0075] [First Modification] A method for manufacturing a molded product 21 according to a first modified example of the present invention will be described with reference to the drawings. In the method for manufacturing a molded product 21 according to the first modified example, in the shield tunnel forming step 1, the intensity distribution of a first laser beam 121 irradiated inside the workpiece 10 is controlled.

[0076] 22 is a cross-sectional view of workpiece 10 illustrating shield tunnel forming step 1 according to the first modified example. In shield tunnel forming step 1 of the first modified example, a first laser beam 121 having a controlled intensity distribution is irradiated onto workpiece 10 to form a shield tunnel 30 inside workpiece 10, the shield tunnel 30 including a pore 31 and a modified region 32 surrounding the pore 31, and also form a crack 35 parallel to first surface 11 at a depth corresponding to thickness 22 of molded article 21 to be manufactured.

[0077] The intensity distribution of the first laser beam 121 includes the intensity distribution in the thickness direction of the workpiece 10. The intensity distribution is controlled, for example, by adjusting a pattern in a spatial light modulator (LCOS; Liquid Crystal On Silicon). If aberration is formed by arranging glass after the condenser of the laser beam irradiation unit 120, the intensity distribution may be controlled by changing the thickness of this glass.

[0078] Usually, when forming the shield tunnel 30, it is preferable to form a focused region 122 having a longitudinal direction in the thickness direction of the workpiece 10, and to irradiate the first laser beam 121 so that the intensity is uniform in the thickness direction. In the shield tunnel forming step 1 according to the second modification, the intensity is increased at a depth corresponding to the thickness 22 of the molded product 21 to be manufactured, thereby promoting the propagation of the crack 35 at that depth.

[0079] [Second Modification] A method for manufacturing a molded product 21 according to a second modified example of the present invention will be described with reference to the drawings. Fig. 23 is a flowchart showing the flow of shield tunnel forming step 1 according to the second modified example. In the method for manufacturing a molded product 21 according to the second modified example, shield tunnel forming step 1 includes a first shield tunnel forming step 1-1 and a second shield tunnel forming step 1-2.

[0080] 24 is a cross-sectional view of the workpiece 10 for explaining the shield tunnel forming step 1 according to the second modified example. In the shield tunnel forming step 1 of the second modified example, the first shield tunnel 30-4 formed on the second surface 12 side and the second shield tunnel 30-5 formed closer to the first surface 11 side than the first shield tunnel 30-4 are formed at different positions in the thickness direction of the workpiece 10.

[0081] First, in a first shield tunnel forming step 1-1, a focusing region 122 of a first laser beam 121 having a wavelength that is transparent to the workpiece 10 is positioned in a first region inside the workpiece 10, and the first laser beam 121 is irradiated along the desired shape, thereby forming a first shield tunnel 30-4 along the desired shape inside the workpiece 10. Next, in a second shield tunnel forming step 1-2, a focusing region 122 of the first laser beam 121 is positioned in a second region inside the workpiece 10, and the first laser beam 121 is irradiated along the desired shape, thereby forming a second shield tunnel 30-5 along the desired shape inside the workpiece 10.

[0082] The first region is a predetermined region extending in the thickness direction inside the workpiece 10. The second region is a predetermined region extending in the thickness direction inside the workpiece 10, and is a region at a different position in the thickness direction from the first region. In the embodiment, the first shield tunnel 30-4 extends from the second surface 12 into the workpiece 10. The second shield tunnel 30-5 extends from the inside of the workpiece 10 to the first surface 11. In the embodiment shown in FIG. 24 , the first shield tunnel 30-4 and the second shield tunnel 30-5 are formed alternately along a desired shape in a plan view, but it is preferable that they overlap, and more preferably that they are in the same position.

[0083] The first shield tunnel 30-4 and the second shield tunnel 30-5 are set to overlap by a predetermined amount or more in the thickness direction at a depth corresponding to the thickness 22 of the molded article 21 to be manufactured. The predetermined amount is preferably 70% or more, and more preferably 85% or more, of the light-collecting area. This allows a crack 35 parallel to the first surface 11 to be formed at a depth corresponding to the thickness 22 of the molded article 21 to be manufactured.

[0084] As described above, in the manufacturing method of the molded article 21 of the embodiment and each modified example, the shield tunnels 30 are formed in the thickness direction along the outline of the planar view shape of the molded article 21 to be manufactured, spanning multiple sheets, and then the separation layer 40 is formed to peel off the substrates one by one in the thickness direction. This eliminates the need to irradiate each substrate with the first laser beam 121 to manufacture the molded article 21, and makes it possible to obtain a molded article 21 of the desired shape in a short time.

[0085] Furthermore, as shown in the first and second modified examples, in the shield tunnel forming step 1, by adjusting the irradiation of the first laser beam 121, it is possible to form a crack 35 parallel to the first surface 11 at a depth corresponding to the thickness 22 of the molded article 21 to be manufactured. This can assist in the formation of the separation layer 40 in the separation layer forming step 2.

[0086] The present invention is not limited to the above-described embodiment, and can be implemented in various modifications without departing from the gist of the present invention.

[0087] For example, there are no limitations on the incident plane of the first laser beam 121 in the shield tunnel formation step 1 and the second laser beam 123 in the separation layer formation step 2. That is, in the shield tunnel formation step 1 and the separation layer formation step 2, the first laser beam 121 and the second laser beam 123 may be irradiated from the same plane (first plane 11) as in the embodiment, or the first laser beam 121 and the second laser beam 123 may be irradiated from different planes.

[0088] In the separation step 3, the separation layer 40 may be peeled off starting from the separation point by applying ultrasonic waves, or an external force may be applied by inserting a wedge from the peripheral surface of the workpiece 10 to peel off starting from the separation layer 40. Furthermore, after applying ultrasonic waves, the first surface 11 and the second surface 12 may be separated by suction, as in the embodiment. When the separation layer 40 is peeled off starting from the separation point by applying ultrasonic waves, it is preferably performed simultaneously with the dividing step 5, in which the molded product 21 is divided starting from the shield tunnel 30. In this case, the flattening step 4 is performed after the separation step 3 and the dividing step 5, and the separation surfaces 23, 24 of the already divided molded product 21 are ground or polished.

[0089] Also, tape may be attached to the first surface 11 side before the separation step 3. Furthermore, tape may be attached to the first surface 11 side before the shield tunnel formation step 1 or the separation layer formation step 2, and the first laser beam 121 and the second laser beam 123 may be irradiated through the tape. By attaching tape to the first workpiece 10-1 side in the separation step 3, the first workpiece 10-1 can be ground or polished in the flattening step 4 while being fixed to the tape, and the workpiece can be prevented from falling apart during division. The tape may be, for example, the expandable tape 51 used in the first example of the division step 5. [Explanation of symbols]

[0090] 10 Workpiece 10-1 First workpiece 10-2 Second workpiece 11 First Side 12 The Second Side 21 Molded products 22 Thickness 23, 24 separation plane 25 Grinding surface 30 Shield Tunnel 31 pores 32 Modification Area 40 separation layer 41 Reforming section 42 Crack 50 frames 51 Expanding Tape 100 Laser processing equipment 110 Holding table 120 Laser beam irradiation unit 121 First Laser Beam 122 Focusing area 123 Second Laser Beam 124 Focusing point 130 Imaging unit 200 Peeling device 210 Holding table 220 Peeling Unit 300 Grinding Equipment 310 Holding Table 320 Grinding Unit 400 Expansion Unit 410 Holding Table 420 Clamping member 430 Lifting Unit 500 liquid tank 510 Loading Net 520 Etching solution

Claims

1. A method for manufacturing a molded product, which obtains a molded product having a desired shape from a workpiece having a first surface and a second surface opposite to the first surface, a shield tunnel forming step of positioning a focused region of a first laser beam having a wavelength that is transparent to the workpiece inside the workpiece and irradiating the first laser beam along the desired shape, thereby forming a shield tunnel along the desired shape, the shield tunnel including a pore extending from the first surface side of the workpiece to a predetermined depth in the thickness direction of the workpiece and a modified region surrounding the pore; a separation layer forming step in which a focal point of a second laser beam having a wavelength that is transparent to the workpiece is positioned at a depth corresponding to the thickness of the molded product to be manufactured from the first surface side, and the focal point and the workpiece are moved relatively to irradiate the workpiece with the second laser beam, thereby forming a separation layer including a modified portion parallel to the first surface and cracks extending from the modified portion; a separation step of separating the workpiece into a first workpiece having the first surface and a second workpiece having the second surface, starting from the separation layer after the shield tunnel forming step and the separation layer forming step are performed; a dividing step of dividing a molded product from the first workpiece along a shield tunnel formed along the desired shape by subjecting the first workpiece to a predetermined treatment; Contains A method for producing a molded article, comprising:

2. The separation layer forming step is performed after the shield tunnel forming step is performed. A method for producing a molded article according to claim 1.

3. The method further includes a planarizing step of flattening the separation surfaces of the first workpiece and the second workpiece separated in the separation step by grinding or polishing the separation surfaces. A method for producing a molded article according to claim 1 or 2.

4. In the division step, The separation surface of the first workpiece is flattened by grinding or polishing the separation surface, and an external force is applied to the first workpiece to separate the molded product from the first workpiece. A method for producing a molded article according to claim 1 or 2.

5. In the division step, An external force is applied to the first workpiece to separate a molded product from the first workpiece along the shield tunnel. A method for producing a molded article according to claim 1 or 2.

6. In the division step, Separating a molded product from the first workpiece along the shield tunnel by etching the first workpiece with an etching agent. A method for producing a molded article according to claim 1 or 2.

7. The shield tunnel forming step includes: a parting assist line setting step of setting a parting assist line between the outer periphery of the workpiece and the molded product; a dividing assist starting point forming step of positioning a focused region of a third laser beam having a wavelength that is transparent to the workpiece inside the workpiece and irradiating the third laser beam along the dividing assist line, thereby forming a shield tunnel including a pore and a modified region surrounding the pore inside the workpiece along the dividing assist line; Contains A method for producing a molded article according to claim 1 or 2.

8. In the shield tunnel forming step, The intensity distribution of the first laser beam irradiated inside the workpiece is controlled, and the first laser beam having the controlled intensity distribution is irradiated onto the workpiece, thereby forming a shield tunnel inside the workpiece, the shield tunnel including a pore and a modified region surrounding the pore, and forming a crack parallel to the first surface at a depth corresponding to the thickness of the molded product to be manufactured. A method for producing a molded article according to claim 1 or 2.

9. The shield tunnel forming step includes: a first shield tunnel forming step of positioning a focused region of the first laser beam in a first region inside the workpiece and irradiating the first laser beam along the desired shape, thereby forming a first shield tunnel along the desired shape, the first shield tunnel including a pore extending along the thickness direction of the workpiece and a modified region surrounding the pore; a second shield tunnel forming step of positioning a focused region of the first laser beam in a second region inside the workpiece that is positioned differently in a thickness direction from the first region, and irradiating the first laser beam along the desired shape, thereby forming a second shield tunnel along the desired shape, the second shield tunnel including a pore extending along the thickness direction of the workpiece and a modified region surrounding the pore; and At a depth corresponding to the thickness of the molded product to be manufactured, the first shield tunnel and the second shield tunnel are set to overlap by a predetermined amount or more along the thickness direction, thereby forming a crack parallel to the first surface at a depth corresponding to the thickness of the molded product to be manufactured. A method for producing a molded article according to claim 1 or 2.

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