Cutting device and cutting method

Abstract

This improves the precision of the groove depth formed on the substrate during dicing. [Solution] A cutting device for cutting a substrate into individual pieces, the substrate comprising a glass substrate and a laminate laminated on the glass substrate, including an insulating layer and a wiring layer, the device comprising: a first driving means for rotating a first cutting tool that forms a groove extending in the cutting direction in the laminate; a second driving means for rotating a second cutting tool that has a narrower width than the groove and cuts the sheet substrate along the groove; and a first moving means for moving the sheet substrate, the first driving means and the second driving means relative to each other, wherein the rotation axis direction of the first driving means is in the thickness direction of the sheet substrate, and the first cutting tool is an end mill.

Description

Technical Field

[0001] The present invention relates to a substrate cutting technique.

Background Art

[0002] Package substrates and interposers for electronic components and the like are manufactured by dicing a large-sized sheet substrate in which a wiring layer and an insulating layer are laminated on a core substrate into individual pieces. Since the core substrate and each layer have different linear expansion coefficients, it is known that stress is generated in the outer peripheral portion of the core substrate due to temperature changes. When a glass substrate is used as the core substrate, minute cracks may occur on the cutting surface during dicing. Depending on the temperature change after dicing, these cracks may spread. In Patent Document 1, a technique has been proposed in which, during dicing, a groove is formed in the laminate and then the sheet substrate is cut along the groove. Since a thin insulating layer remains in the shape of a core substrate near the cutting surface where the groove is formed, it is effective in preventing the spread of cracks.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] If the groove formed in the laminate is too deep, the cutting tool may reach the core substrate and damage the core substrate. If the groove is too shallow, the effect of suppressing the spread of cracks due to temperature changes is reduced. In the method of Patent Document 1, a dicing blade is used for forming the groove, and it is not easy to ensure the accuracy of the groove depth. Further, the shape of the groove may vary due to the progress of wear of the dicing blade.

[0005] An object of the present invention is to improve the accuracy of the depth of a groove formed in a substrate during dicing.

Means for Solving the Problems

[0006] According to the present invention, A cutting apparatus for cutting a sheet substrate into individual pieces, the sheet substrate having a glass substrate and a laminate laminated on the glass substrate, which includes an insulating layer and a wiring layer, A first driving means for rotating a first cutting tool that forms grooves extending in the cutting direction in the laminate, A second driving means for rotating a second cutting tool having a narrower width than the groove and cutting the sheet substrate along the groove, The device comprises the sheet substrate, the first driving means and the second driving means, and a first moving means that moves them relative to each other. The rotation axis direction of the first driving means is in the thickness direction of the sheet substrate, The first cutting tool is an end mill. A cutting device characterized by the above is provided. [Effects of the Invention]

[0007] According to the present invention, the accuracy of the depth of the grooves formed in the substrate during dicing can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] A plan view of a cutting device according to one embodiment of the present invention. [Figure 2] Side view of the cutting device shown in Figure 1. [Figure 3] (A) is a diagram showing an example of a sheet substrate to be cut, and (B) is a block diagram of the control unit of the cutting device in Figure 1. [Figure 4] Figure 1 is an explanatory diagram of the operation of the cutting device. [Figure 5] Figure 1 is an explanatory diagram of the operation of the cutting device. [Figure 6] (A) is a diagram showing an example of measurement of the formation surface of the substrate, (B) is a diagram showing the groove formation process, and (C) is a diagram showing an example of controlling the cutting depth of the cutting tool. [Figure 7] Figure 1 is an explanatory diagram of the operation of the cutting device. [Figure 8]Operation explanatory diagram of the cutting device of FIG. 1. [Figure 9] Operation explanatory diagram of the cutting device of FIG. 1. [Figure 10] Operation explanatory diagram of the cutting device of FIG. 1. [Figure 11] Diagram showing the cutting operation. [Figure 12] Diagram showing a comparative example of the groove forming operation.

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are necessary, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0010] <First Embodiment> (Outline of the device) FIG. 1 is a plan view schematically showing a cutting device 1 according to an embodiment of the present invention, FIG. 1 is a side view of the cutting device 1, and FIG. 3(A) is a perspective view of a sheet substrate 200 to be cut. In each figure, arrows X, Y, and Z indicate directions intersecting each other, and in the case of this embodiment, they are orthogonal. The X direction and the Y direction are horizontal directions, and the Z direction is a vertical direction.

[0011] The cutting device 1 is a device that cuts the sheet substrate 200 along the grid-like division planned lines 203 and 204 to individualize it. The sheet substrate 200 has a glass substrate 201 and a laminate 202, and in the case of this embodiment, its outer shape is rectangular, particularly square. The sheet substrate 200 assumed in this embodiment has laminates 202 laminated on both surfaces of the glass substrate 201. However, the laminate 202 may be laminated only on one side of the glass substrate 201.

[0012] The glass substrate 201 is formed of, for example, borosilicate glass, alkali-free glass, quartz glass, or the like. The laminate 202 includes wiring layers made of conductors such as metal and insulating layers made of insulators such as resin, and adjacent wiring layers are insulated from each other by the insulating layers. The glass substrate 201 has, for example, through holes penetrating in the thickness direction, and electrodes made of conductors such as metal are embedded in the through holes. The wiring layers on the front and back surfaces of the glass substrate 201 are connected via these electrodes.

[0013] Note that in the portions corresponding to the planned division lines 203 and 204, the laminate 202 has no wiring layer and only an insulating layer. Further, when arranging the above-described electrodes on the glass substrate 201, the electrodes are arranged at positions different from the portions corresponding to the planned division lines 203 and 204.

[0014] The sheet substrate 200 is cut along the planned division lines 203 and 204, and is thereby separated into, for example, a plurality of package substrates or a plurality of interposers.

[0015] The cutting device 1 includes a stage unit 2 on which the sheet substrate 200 is placed. The stage unit 2 includes a stage 21 and a rotation unit 22 that rotates the stage 21 around a rotation axis Z1 in the Z direction. The stage 21 has a horizontal placement surface on which the sheet substrate 200 is placed. On the placement surface, a large number of suction holes for vacuum-sucking the sheet substrate 200 are formed, for example, and during the cutting operation, the sheet substrate 200 is held by the stage 21. Further, a slit 21a (see FIGS. 6(B) and 11) that allows the entry of a cutting tool 60 described later is formed on the placement surface. The slit 21a is formed at positions corresponding to each of the planned division lines 203 and 204.

[0016] The rotating unit 22 is positioned below the stage 21 and rotates the stage 21 around the Z1 axis by a mechanism, for example, a motor as the drive source. By rotating the stage 21 by 90 degrees, the orientation of the sheet substrate 200 on the stage 21 can be changed so that the division line 203 of the mutually orthogonal division lines 203 and 204 is oriented in the Y direction, and the division line 204 is oriented in the Y direction.

[0017] The cutting device 1 includes a stage moving unit 3 that moves the sheet substrate 200 in the Y direction. The moving unit includes a pair of rail members 31. Each rail member 31 extends in the Y direction, and the pair of rail members 31 are spaced apart from each other in the X direction. The stage unit 2 is provided with a plurality of sliding members 23 that engage with the rail members 31 and slide in the Y direction. The stage unit 2 is capable of reciprocating horizontally in the Y direction guided by the pair of rail members 31.

[0018] The stage moving unit 3 includes a pair of support members 32 that support a pair of rail members 31. Each support member 32 extends in the Y direction, and the pair of support members 32 are spaced apart from each other in the X direction. A drive unit 33 is positioned between the pair of support members 32. In this embodiment, the drive unit 33 is a ball screw mechanism and includes a motor 331, which is the drive source, and a ball screw shaft 332 that extends in the Y direction. A nut unit 333 having a ball nut that screws onto the ball screw shaft 332 is fixed to the stage unit 2. The rotation of the ball screw shaft 332 around its axis in the Y direction by the drive of the motor 331 allows the stage unit 2 to be moved in the Y direction.

[0019] The cutting device 1 includes a drive unit 4 that rotates a cutting tool 40 using a motor as the driving source. The drive unit 4 rotates the cutting tool 40 around a rotation axis Z2 in the Z direction, allowing the sheet substrate 200 to be cut by the cutting tool 40. The drive unit 4 is supported by a movement unit 9 via a tool movement unit 5. The tool movement unit 5 is a lifting mechanism that moves the drive unit 4 in the Z direction using a motor as the driving source. By changing the height of the cutting tool 40 using the tool movement unit 5, the cutting depth of the cutting tool 40 in the sheet substrate 200 can be changed.

[0020] The cutting device 1 includes a drive unit 6 that rotates a cutting tool 60 using a motor as the driving source. The drive unit 6 rotates the cutting tool 60 around the rotation axis X1 in the X direction, and the sheet substrate 200 can be cut by the cutting tool 60 with the Y direction as the cutting direction. The drive unit 6 is supported by a movement unit 9 via a tool movement unit 7. The tool movement unit 7 is a lifting mechanism that moves the drive unit 6 in the Z direction using a motor as the driving source. By changing the height of the cutting tool 60 with the tool movement unit 7, the position of the cutting tool 60 can be changed between a cutting position for cutting the sheet substrate 200 and an upper retracted position.

[0021] The cutting device 1 includes a measuring unit 8 supported by a moving unit 9. The measuring unit 8 measures the shape of the upper surface of the sheet substrate 200 held by the stage unit 2. In this embodiment, the measuring unit 8 is a laser displacement meter and measures the distance between the upper surface of the sheet substrate 200 and the measuring unit 8. The measuring unit 8 may be another sensor capable of measuring the shape of the upper surface of the sheet substrate 200, such as a camera.

[0022] The moving unit 9 is a mechanism for moving the tool moving units 5 and 7 and the measuring unit 8 in the X direction. The moving unit 9 includes a beam member 90 that is positioned to traverse the stage moving unit 3 by a pair of support columns 10 spaced apart in the X direction. The tool moving units 5 and 7 are each independently supported by the beam member 90 so as to be movable in the X direction.

[0023] The beam member 90 is provided with drive mechanisms 91 to 93. Drive mechanism 91 independently moves the tool moving unit 5, drive mechanism 92 independently moves the measuring unit 8, and drive mechanism 93 independently moves the tool moving unit 7 in the X direction. Each of the drive mechanisms 91 to 93 is, for example, a ball screw mechanism driven by a motor.

[0024] The cutting device 1 includes a reversal unit 11 that determines the front and back sides of the sheet substrate 200. The reversal unit 11 includes a support column 12. A pair of rail members 13 are supported on the Y-direction side of the support column 12. Each rail member 13 extends in the Z-direction, and the pair of rail members 13 are spaced apart from each other in the X-direction.

[0025] The inversion unit 11 includes a suction unit 19 for temporarily holding the sheet substrate 200. The suction unit 19 comprises a rectangular frame 191 and a plurality of suction parts 192 supported by the frame 191. The frame 191 is supported so as to be suspended from a support member 120 extending in the Y direction. The suction parts 192 are, for example, vacuum pads that vacuum-suction the upper surface of the sheet substrate 200. The suction parts 192 may also be adhesive sheets called die attach films (DAFs).

[0026] The reversing unit 11 includes a U-shaped substrate holding frame 16 in plan view. The substrate holding frame 16 includes a pair of arm portions 16a spaced apart in the X direction and a connecting portion 16b connecting the pair of arm portions 16a. Each arm portion 16a is a plate-shaped member on the YZ plane, and a holding unit 17 is positioned inside it. The holding unit 17 has a clamping mechanism that clamps the edge of the sheet substrate 200 in the X direction and is supported by the arm portion 16a via a rotating unit 171. The rotating unit 171 is equipped with a motor as a drive source and rotates the holding unit 17 around a rotation axis X2 in the X direction. The connecting portion 16b is a plate-shaped member on the XZ plane. The connecting portion 16b is provided with a plurality of sliding members 14 that engage with a rail member 13 and slide in the Z direction. The substrate holding frame 16 can reciprocate in the Z direction guided by the pair of rail members 13.

[0027] The support column 12 also has a drive unit 18 built into it. The drive unit 18 is a mechanism for raising and lowering the substrate holding frame 16, and is, for example, a ball screw mechanism driven by a motor.

[0028] (Control unit) Figure 3(B) is a block diagram of the control unit 100 of the cutting device 1. The control unit 100 is an electronic circuit including a processing unit 101, a storage unit 102, and an interface (I / F) 103. The processing unit 101 is a processor, such as a CPU, and executes programs stored in the storage unit 102. The storage unit 102 is a storage device such as a semiconductor memory. The input / output I / F 103 includes input / output interfaces and communication interfaces with external devices. The storage unit 102 stores programs executed by the processing unit 101 and data used by the processing unit 101 for processing. The processing unit 101 controls the actuator 105 based on instructions from a higher-level device and detection results from the sensor 104. The sensor 104 includes sensors provided by the measurement unit 8 (a laser displacement meter in this embodiment) and sensors that detect the rotation amount of each motor. The actuator 105 includes the motor 331, the motors of drive units 4 and 6, the motors of tool moving units 5 and 7, the motors of drive mechanisms 91 to 94, the motor of drive unit 18, and pumps and valves that drive the suction part 192.

[0029] (Cutting tools) While the use of glass substrates in packaging substrates and interposers offers advantages in terms of electrical properties, it presents a challenge in preventing cracking. The impact generated during dicing of glass substrates, which are prone to cracking, can cause microscopic cracks to form on the cut surface of the glass substrate. These microscopic cracks, combined with temperature changes immediately after dicing or in subsequent processes, release internal stress accumulated within the glass substrate, potentially causing the cracks to spread in a direction that leads to the glass substrate splitting.

[0030] In this embodiment, a cutting tool 40 is used to form grooves in the sheet substrate 200 along the planned division lines 203 and 204, and then the sheet substrate 200 is cut along the grooves using a cutting tool 60. In forming the grooves, grooves are formed in the laminate 202 that do not reach the glass substrate 201. A thin insulating layer remains near the cut surface of the glass substrate 201, which solves the crack problem described above.

[0031] The groove depth varies depending on the thickness of the laminate 202, but the thickness of the laminate 202 remaining on the glass substrate 201 is preferably 10 μm or more and 100 μm or less. More preferably, it is desirable to have a thickness of 20 μm or more and 60 μm or less. By setting the thickness of the laminate 202 remaining on the glass substrate 201 to 100 μm or less, the probability of delamination occurring at the interface between the laminate 202 and the glass substrate 201, or of crack propagation in the glass substrate 201, due to differences in the coefficient of linear expansion can be reduced, and this probability can be reduced more reliably by setting it to 60 μm or less. By setting the thickness of the laminate 202 remaining on the glass substrate 201 to 10 μm or more, the possibility of the cutting tool 40 coming into contact with the glass substrate 201 can be reduced, and the possibility of contact can be reduced more reliably by setting it to 20 μm or more.

[0032] In this embodiment, the cutting tool 40 is an end mill, and the cutting tool 60 is a dicing blade. By using an end mill to form the groove, the accuracy of the groove depth can be improved compared to when using a dicing blade, thereby enabling such precision machining. For example, in this embodiment, the groove depth can be adjusted by the position of the end mill in the rotation axis direction. When controlling the groove depth with a dicing blade, the adjustment is made by the position of the dicing blade in the diametrical direction, which is disadvantageous in terms of accuracy.

[0033] In terms of wear, end mills are also more advantageous than dicing blades. Figure 12 is a schematic diagram showing the wear of the dicing blade and the change in the cross-sectional shape of the groove when a groove is machined using a dicing blade as a comparative example.

[0034] Immediately after truing, as shown in state ST101, the peripheral edge of the dicing blade 400 has a gently sloping cross-sectional shape, and therefore the cross-sectional shape of the groove 202a formed in the laminate 202 of the sheet substrate 200' is also gently formed. However, as wear of the dicing blade 400 progresses, as shown in state ST102, the peripheral edge of the dicing blade 400 changes to a tapered cross-sectional shape, and the cross-sectional shape of the groove 202b formed in the laminate 202 of the sheet substrate 200' also becomes narrower in the deeper parts. As wear of the dicing blade 400 progresses further, as shown in state ST103, the peripheral edge of the dicing blade 400 changes to a triangular cross-sectional shape, and the cross-sectional shape of the groove 202c formed in the laminate 202 of the sheet substrate 200' also becomes closer to a triangular shape. Subsequently, when the glass substrate 201 is cut with a dicing blade, the stress of the laminate 202 acts strongly on the cut portion of the glass substrate 201, causing the glass substrate 201 to crack or the laminate 202 and glass substrate 201 to separate.

[0035] The end mill does not experience the same level of wear as a dicing blade 400, and by using an end mill as the cutting tool 40 for forming grooves, as in this embodiment, grooves can be formed with a stable shape.

[0036] The end mill used as the cutting tool 40 can be selected according to the material, shape, groove width, and depth of the laminate 202. The laminate 202 is a ductile material mainly composed of resin and copper, and is resistant to chipping. In this respect, suitable end mill materials include, for example, ultrafine grain cemented carbide or CBN. Suitable end mill shapes include, for example, square end mills capable of machining grooves with a nearly square cross-section (e.g., RSE230 from Nisshin Tool Co., Ltd.) and radius end mills capable of machining grooves with a small R shape at the bottom (e.g., SHPR230 from Nisshin Tool Co., Ltd.).

[0037] The dicing blade used as the cutting tool 60 is a dicing blade that is narrower than the groove formed by the cutting tool 40. A resin-bonded dicing blade using resin as a binder is preferred. The blade width is generally in the range of 0.1 mm to 0.5 mm, and in the case of a resin-bonded blade, a width in the range of 0.2 mm to 0.4 mm is even more preferred. The average particle size of the abrasive grains is preferably between 5 μm and 40 μm.

[0038] (Warping of the sheet substrate) The demand for higher frequencies and speeds has become significant due to the demand for AI-related products, and there is a need to increase the size of sheet substrates to ensure sufficient capacity. In addition, with the increasing density of wiring boards, some sheet substrates have 10 or more wiring layers, and the stress on the glass substrate is increasing in proportion to the number of wiring layers. As a result, the problem of warping in sheet substrates is becoming more pronounced. In particular, glass substrates are used not only as package substrates and interposers, but also as semiconductor support substrates and support carriers for wiring boards. In these substrates, the laminate is formed on only one side of the glass substrate. When the laminate is formed on only one side of the glass substrate, the stress from the laminate is applied to only one side of the glass substrate, so the warping of the sheet substrate becomes more pronounced.

[0039] In this embodiment, the shape of the upper surface (groove formation surface) of the sheet substrate 200 can be measured by the measurement unit 8. Furthermore, an end mill is used as the cutting tool 40 for forming the groove, and the cutting depth of the cutting tool 40 into the sheet substrate 200 can be adjusted by the tool movement unit 5. Therefore, the cutting depth of the cutting tool 40 can be adjusted in response to the warping of the sheet substrate 200, and the groove depth can be controlled with higher precision.

[0040] (Control example) An example of the operation of the cutting device 1 controlled by the processing unit 101 will be explained with reference to Figures 4, 5, and 7-11. These figures are explanatory diagrams of the operation of the cutting device 1.

[0041] State ST1 in Figure 4 shows the state in which the sheet substrate 200 to be cut is placed on the stage unit 2. The sheet substrate 200 is attracted and held by the stage 21 of the stage unit 2. First, grooves are formed on the sheet substrate 200 along each planned division line 203. As a result, the sheet substrate 200 is held on the stage unit 2 in a position in which the planned division lines 203 are oriented in the Y direction.

[0042] When the sheet substrate 200 is held by the stage unit 2, the shape of the upper surface (groove formation surface) of the sheet substrate 200 is measured. The drive mechanism 92 of the moving unit 9 moves the measurement unit 8 to the measurement position in the X direction as shown in state ST2 of Figure 1. In this embodiment, the measurement position is the center of the sheet substrate 200 in the X direction, and the measurement result at the center position is used as a representative value of the shape in the Y direction over the entire area of ​​the sheet substrate 200 in the X direction. As another example, the shape of the upper surface of the sheet substrate 200 may be measured by the measurement unit 8 at each planned division line 203.

[0043] Next, as shown in state ST3, the stage unit 2 is moved in the Y direction by the stage movement unit 3, causing the sheet substrate 200 to pass below the measurement unit 8. The measurement unit 8 measures the distance in the Z direction between the measurement unit 8 and the upper surface of the sheet substrate 200, corresponding to the position of the sheet substrate 200 in the Y direction. Once the measurement is complete, the measurement unit 8 is returned to its original position by the drive mechanism 92 of the movement unit 9.

[0044] Figure 6(A) is a schematic diagram showing the measurement results. As an example, the upper surface of the stage unit 2 (the mounting surface of the stage 21) is set as the reference height Zref, and the measurement result of the measurement unit 8 is obtained as height Z(y) relative to the reference height Zref. Height Z(y) is information about the position in the Z direction of the upper surface of the sheet substrate 200 corresponding to a part of the sheet substrate 200 in the Y direction. Z(y) may also be a function. In the illustrated example, it is assumed that the sheet substrate 200 is curved so as to be convex upward in the center in the Y direction. Z(y) is maximum in the center of the sheet substrate 200 in the Y direction and minimum at both ends.

[0045] Next, the groove formation process using the cutting tool 40 begins. As shown in state ST4 in Figure 5, the drive mechanism 91 of the moving unit 9 moves the drive unit 4, together with the tool moving unit 5, in the X direction to the first groove formation position corresponding to the position of one of the planned division lines 203. As shown in state ST5 in Figure 5, the tool moving unit 5 lowers the drive unit 4, moving the cutting tool 40 to the first cutting position in the Z direction. The cutting position in the Z direction is set by the measurement results of the measurement unit 8.

[0046] Next, the cutting of the groove begins. The drive unit 4 is driven to start the rotation of the cutting tool 40, and the stage moving unit 3 moves the stage unit 2 in the Y direction. The stage unit 2 is moved so that the sheet substrate 200 passes over the cutting tool 40. While the stage unit 2 is moving, the tool moving unit 5 is controlled so that the cutting position of the cutting tool 40 in the Z direction changes based on the Y direction of the sheet substrate 200 and the measurement results of the measurement unit 8.

[0047] Figure 6(B) is a cross-sectional view showing the formation of groove 202a by the cutting tool 40. The cutting tool 40 has its rotation axis Z2 in the direction of the thickness direction (normal direction) of the sheet substrate 200 and cuts into the laminate 202 at a position that does not reach the glass substrate 201. As the sheet substrate 200 moves continuously in the Y direction, groove 202a extending in the Y direction is formed. The groove 202a is formed on the slit 21a corresponding to the planned division line 203 of the stage 21.

[0048] Figure 6(C) schematically shows the change in the cutting position of the cutting tool 40 in the Z direction. The tool movement unit 5 is controlled in accordance with the height Z(y) exemplified in Figure 6(A), and the cutting position (depth of cut) of the cutting tool 40 in the Z direction is controlled. A groove 202a of uniform depth can be formed over the entire Y direction to accommodate the warping of the sheet substrate 200.

[0049] Once the formation of a groove 202a corresponding to one division line 203 is complete, a groove 202a corresponding to another division line 203 is formed. As shown in state ST7 in Figure 7, the drive mechanism 91 of the moving unit 9 moves the drive unit 4, together with the tool moving unit 5, in the X direction to a groove formation position corresponding to the next division line 203. Then, the cutting tool 40 is moved to the first cutting position in the Z direction. The drive unit 4 is driven to start the rotation of the cutting tool 40, and the stage moving unit 3 moves the stage unit 2 in the Y direction, as shown in state ST8 in Figure 7. While the stage unit 2 is moving, the tool moving unit 5 is controlled so that the cutting position of the cutting tool 40 in the Z direction changes based on the Y direction of the sheet substrate 200 and the measurement results of the measurement unit 8.

[0050] By repeating the above procedure, grooves 202a corresponding to all planned division lines 203 are formed.

[0051] Next, the process moves on to forming the groove 202a corresponding to the planned division line 204. As shown in state ST9 in Figure 7, the stage 21 is rotated 90 degrees together with the sheet substrate 200 by the rotation unit 22 of the stage unit 2. This positions the sheet substrate 200 so that the planned division line 204 is facing in the Y direction. Subsequently, the groove 202a corresponding to the planned division line 204 is formed by the cutting tool 40 in the procedure described in states ST2 to ST8 above.

[0052] Next, the process moves on to forming grooves 202a on the back side of the sheet substrate 200 corresponding to the planned division lines 203 and 204. First, the front and back sides of the sheet substrate 200 are reversed using the reversal unit 11. The operation of the reversal unit 11 will be explained with reference to the operation diagrams in Figures 8 and 9.

[0053] The drive unit 18 lowers the substrate holding frame 16 onto the stage unit 2 as shown in state ST10 of Figure 8, and the holding unit 17 holds both ends of the sheet substrate 200 in the X direction. After the suction of the sheet substrate 200 by the stage 21 is released, the drive unit 18 raises the substrate holding frame 16 as shown in state ST11 of Figure 8, and the sheet substrate 200 is separated from the stage unit 2.

[0054] Driven by the rotation unit 171, the holding unit 17 rotates together with the sheet substrate 200 as shown in state ST12 of Figure 8, and the front and back sides of the sheet substrate 200 are reversed. The drive unit 18 further raises the substrate holding frame 16 as shown in state ST13 of Figure 9, and the sheet substrate 200 reaches the suction unit 19. The suction part 192 holds the sheet substrate 200 in the suction unit 19. As shown in state ST14 of Figure 9, the holding unit 17 releases the sheet substrate 200, and then the holding unit 17 holds the sheet substrate 200 again (re-gripping).

[0055] The drive unit 18 lowers the substrate holding frame 16 onto the stage unit 2 as shown in state ST15 in Figure 9, and the sheet substrate 200 is placed back onto the stage 21. After the stage 21 picks up the sheet substrate 200 again, the holding unit 17 releases its grip on the sheet substrate 200.

[0056] This completes the process of reversing the front and back sides of the sheet substrate 200. Subsequently, grooves 202a corresponding to the planned division lines 203 and 204 are formed by the cutting tool 40 in the procedure described in states ST2 to ST9 above.

[0057] Next, the sheet substrate 200 is cut along the groove 202a using the cutting tool 60 to separate it into individual pieces. Figure 10 is an explanatory diagram of this operation.

[0058] As shown in state ST16 of Figure 10, the drive mechanism 93 of the moving unit 9 moves the drive unit 6 together with the tool moving unit 7 in the X direction to the first cutting position corresponding to the position of one of the planned division lines 204. As shown in state ST17 of Figure 10, the tool moving unit 7 lowers the drive unit 6, moving the cutting tool 60 to the cutting position in the Z direction. The cutting position in the Z direction is predetermined and is the position where the cutting tool 60 enters the slit 21a.

[0059] Next, cutting of the sheet substrate 200 is started. The drive unit 6 is driven to start the rotation of the cutting tool 60, and the stage unit 2 is moved in the Y direction by the stage moving unit 3, as shown in state ST18 in Figure 10. The stage unit 2 is moved so that the sheet substrate 200 passes over the cutting tool 60.

[0060] Figure 11 is a cross-sectional view showing the cutting of the sheet substrate 200 by the cutting tool 60. Grooves 202a have already been formed on both the front and back surfaces of the sheet substrate 200 by the procedure described above. The width of the dicing blade, which is the cutting tool 60, in the thickness direction is narrower than the width of the groove 202a in the X direction, and the position of the dicing blade in the X direction is at the center of the groove 202a in the X direction. The peripheral edge of the dicing blade enters the slit 21a. The remaining portion of each laminate 202 in the glass substrate 201 and groove 202a is cut by the cutting tool 60.

[0061] Once the sheet substrate 200 has been cut along one planned division line 204, the sheet substrate 200 is cut along another planned division line 204. This is similar to the groove formation process 202a. Specifically, the drive mechanism 93 of the moving unit 9 moves the drive unit 6, together with the tool moving unit 7, in the X direction to a cutting position corresponding to the next planned division line 204. The drive unit 6 is driven to start the rotation of the cutting tool 60, and the stage moving unit 3 moves the stage unit 2 in the Y direction. By repeating the above procedure, the sheet substrate 200 is cut along all planned division lines 204.

[0062] Next, the sheet substrate 200 is cut along the planned division lines 203 using the cutting tool 60. This is similar to the groove formation process 202a. Specifically, the stage 21 is rotated 90 degrees along with the sheet substrate 200 by the rotation unit 22 of the stage unit 2. This positions the sheet substrate 200 so that the planned division lines 203 are oriented in the Y direction. Subsequently, the sheet substrate 200 is cut along each planned division line 203 using the procedure described above.

[0063] As described above, according to this embodiment, by using an end mill as the cutting tool 40, the groove 202a can be formed with high precision, and by using a dicing blade as the cutting tool 60, the sheet substrate 200 can be cut along the groove 202a.

[0064] (Example test) A test was conducted to cut a sheet substrate using a device equivalent to cutting device 1. The conditions and results are described below.

[0065] • Test example 1 A 250mm square sheet substrate was cut into individual pieces to obtain nine 70mm square package substrates. The glass substrate constituting the sheet substrate was made of 1mm thick alkali-free glass. Through-holes were formed in the glass substrate to allow conductivity between the front and back surfaces. A laminate was laminated on each side of the glass substrate. The laminate has 10 insulating layers and 10 copper wiring layers. Along the planned division line, the laminate consists only of a 350μm thick insulating layer. The amount of warping was 1.2mm.

[0066] This section describes the groove machining conditions using an end mill. A groove with a width of 1 mm and a depth of 310 μm was formed in the laminate. To form a 20 μm radius at the bottom of the groove, a radius end mill with an outer diameter of 1 mm, a cutting edge length of 0.7 mm, a neck diameter of 0.95 mm, and 4 cutting edges was used. The end mill rotation speed was set to 3000 rpm, and the feed rate of the sheet substrate was set to 20 mm / s. Cutting fluid was applied during machining to prevent deformation of the end mill and sheet substrate due to heat generated during machining.

[0067] Next, the cutting conditions using the dicing blade will be described. A resin-bonded dicing blade with a thickness of 0.3 mm, an outer diameter of 80 mm, and diamond abrasive grains of #1000 was used. The rotation speed of the dicing blade was set to 3000 rpm, and the feed rate of the sheet substrate was set to 3 mm / s. The dicing blade and sheet substrate were cooled with water before cutting. The resulting pieces were in good condition with no chipping, peeling, or cracking.

[0068] • Test example 2 A 300mm square sheet substrate was cut into individual pieces to obtain 25 50mm square interposers. The glass substrate constituting the sheet substrate was made of 0.5mm thick alkali-free glass. Through-holes were formed in the glass substrate to allow conductivity between the front and back surfaces. Laminates were laminated on both sides of the glass substrate. Each laminate has three insulating layers and three copper wiring layers. Along the planned dividing line, the laminate consists only of an insulating layer approximately 100μm thick. The amount of warping was 1.0mm.

[0069] This section describes the groove machining conditions using an end mill. A groove with a width of 0.8 mm and a depth of 700 μm was formed in the laminate. A square end mill with an outer diameter of 0.8 mm, a cutting edge length of 2.4 mm, and 2 cutting edges was used. The end mill rotation speed was 200 rpm, and the feed rate of the sheet substrate was 20 mm / s. Cutting fluid was applied during machining to prevent deformation of the end mill and sheet substrate due to heat generated during machining.

[0070] Next, the cutting conditions using the dicing blade will be described. A resin-bonded dicing blade with a thickness of 0.3 mm, an outer diameter of 80 mm, and diamond abrasive grains of #1000 was used. The rotation speed of the dicing blade was set to 3000 rpm, and the feed rate of the sheet substrate was set to 6 mm / s. The dicing blade and sheet substrate were cooled with water before cutting. The resulting pieces were in good condition with no chipping, peeling, or cracking.

[0071] <Other Embodiments> In the first embodiment, an example was described in which a laminate 202 was laminated on both sides of a glass substrate 201 as a sheet substrate 200. When the laminate 202 is laminated on only one side of the glass substrate 201, the sheet substrate 200 does not need to be reversed by the reversing unit 11. Other operations are the same as in the first embodiment, and after forming each groove 202a with the cutting tool 40, the sheet substrate 200 is cut with the cutting tool 60. As described above, when the laminate 202 is formed on only one side of the glass substrate 201, stress from the laminate 202 is applied to only one side of the glass substrate 201, so the warping of the sheet substrate 200 becomes more pronounced. Therefore, as described in the first embodiment, the grooves 202a can be formed more appropriately by adjusting the cutting depth of the cutting tool 40 based on the measurement results of the measurement unit 8.

[0072] In the first embodiment, the sheet substrate 200 was moved in the Y direction by the stage moving unit 3 relative to the cutting tools 40 and 60. However, it is sufficient that they can be moved relative to each other. The position of the sheet substrate 200 may be fixed, and the cutting tools 40 and 60 may be moved in the Y direction. Alternatively, the sheet substrate 200 and the cutting tools 40 and 60 may be moved in opposite directions in the Y direction.

[0073] Furthermore, the present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0074] The technical ideas derived from this disclosure are not limited to the exemplary embodiments disclosed, but are intended to encompass various modifications of the exemplary embodiments, or substitutions with equivalent structures or functions. The scope of the following claims should be interpreted in the broadest way to encompass all such modifications and equivalent structures and functions. [Explanation of Symbols]

[0075] 1 cutting device, 200 sheet substrates, 201 glass substrates, 202 laminates, 40 cutting tools, 4 drive units, 60 cutting tools, 6 drive units, 3 stage moving units

Claims

1. A cutting apparatus for cutting a sheet substrate into individual pieces, the sheet substrate having a glass substrate and a laminate laminated on the glass substrate, which includes an insulating layer and a wiring layer, A first driving means for rotating a first cutting tool that forms grooves extending in the cutting direction in the laminate, A second driving means for rotating a second cutting tool having a narrower width than the groove and cutting the sheet substrate along the groove, The device comprises the sheet substrate, the first driving means and the second driving means, and a first moving means that moves them relative to each other. The rotation axis direction of the first driving means is in the thickness direction of the sheet substrate, The first cutting tool is an end mill. A cutting device characterized by the following features.

2. A cutting device according to claim 1, The rotation axis direction of the second driving means is perpendicular to the rotation axis direction of the first driving means. The second cutting tool is a dicing blade. A cutting device characterized by the following features.

3. A cutting device according to claim 1, The first driving means is moved in the direction of the rotation axis, The system includes a control means for adjusting the depth of the groove by controlling the second moving means, A cutting device characterized by the following features.

4. A cutting device according to claim 3, The system includes a measuring means for measuring the shape of the forming surface of the sheet substrate that forms the groove, The control means adjusts the depth of the groove based on the measurement result of the measuring means. A cutting device characterized by the following features.

5. A cutting device according to claim 1, The sheet substrate is equipped with a reversal means for reversing the front and back sides, The laminate is laminated on both sides of the sheet substrate, The grooves are formed on both sides of the sheet substrate. A cutting device characterized by the following features.

6. A cutting device according to claim 1, The end mill mentioned above is either a radius end mill or a square end mill. A cutting device characterized by the following features.

7. A cutting device according to claim 1, The aforementioned sheet substrate is a substrate that is separated into individual pieces for a package substrate or interposer. A cutting device characterized by the following features.

8. A cutting method for cutting a sheet substrate, which has a glass substrate and a laminate laminated on the glass substrate including an insulating layer and a wiring layer, into individual pieces, A groove forming step involves rotating a first cutting tool to form grooves extending in the cutting direction in the laminate by the first cutting tool, The cutting step includes rotating a second cutting tool having a narrower width than the groove, and cutting the sheet substrate along the groove with the second cutting tool, The rotation axis direction of the first cutting tool is in the thickness direction of the sheet substrate. The first cutting tool is an end mill. A cutting method characterized by the following features.

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