Method for manufacturing chips, and cutting apparatus
The described method and apparatus for cutting substrates like β-Ga2O3 use ultrasonic vibration and staged cutting to prevent chipping and reduce cutting time by forming a cutting groove and then removing the remaining portion, addressing the inefficiencies of traditional cutting methods.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- DISCO CORP
- Filing Date
- 2025-10-29
- Publication Date
- 2026-07-07
AI Technical Summary
Existing methods for cutting substrates like β-gallium oxide (β-Ga2O3) with a cutting blade result in chipping due to its cleavage properties, and reducing the feed rate to prevent chipping prolongs the cutting time.
A method involving a cutting apparatus with a holding table and a cutting unit that vibrates the cutting blade ultrasonically in a down-cut direction to form a cutting groove on one surface without reaching the other, followed by an up-cut direction to remove the remaining portion, allowing for faster cutting while minimizing chipping.
This approach effectively suppresses chipping and reduces cutting time by allowing higher feed rates during the cutting process, particularly when dividing substrates prone to cleavage along specific planes.
Smart Images
Figure 2026113403000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for manufacturing chips by dividing a substrate into a plurality of chips and a cutting device for dividing the substrate.
Background Art
[0002] As a method for dividing a plurality of devices formed on the surface of a substrate such as a semiconductor wafer into chips, a method of cutting the substrate with a cutting blade along a planned cutting line (street) of the substrate is known.
[0003] In cutting with a cutting blade, chipping (chipping) may occur on the cut end face of the substrate. In order to suppress such chipping, for example, in Patent Document 1, after forming a cutting groove that does not reach the other surface by cutting from one surface of the substrate with a cutting blade, the remaining portion is cut from the other surface to divide the substrate. A technique is described.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] By the way, when cutting a substrate having a cleavage property that is easy to cleave along a specific surface such as β-gallium oxide (β-Ga2O3) with a cutting blade, in order to prevent chipping due to cleavage, a means of reducing the feed rate of cutting may be adopted. However, with this means, the cutting time becomes long, and there is a problem.
[0006] One of the objects of the present invention is to provide a method for manufacturing chips and a cutting device that can shorten the cutting time while suppressing chipping.
Means for Solving the Problems
[0007] The present invention A method for manufacturing chips, comprising dividing a substrate having a first surface and a second surface opposite to the first surface along a plurality of division lines set in a grid pattern, thereby manufacturing a plurality of chips, A holding step of holding the second surface of the substrate with a holding table so that the first surface of the substrate is exposed, A cutting groove forming step, in which the cutting blade is rotated in a down-cut direction from the first surface toward the second surface while vibrating the cutting blade at a frequency in the ultrasonic band, thereby cutting the substrate along the planned division line and forming a cutting groove on the first surface that does not reach the second surface, The method includes a first dividing step, in which, after the cutting groove forming step, the cutting blade is rotated in an up-cut direction from the second surface toward the first surface to cut away the remaining portion of the dividing line in which the cutting groove has been formed.
[0008] Furthermore, the present invention is A cutting apparatus for manufacturing multiple chips by dividing a substrate having a first surface and a second surface opposite to the first surface along a plurality of division lines set in a grid pattern, A holding table that holds the second surface of the substrate so that the first surface of the substrate is exposed, A cutting unit having a cutting blade, which cuts the substrate by moving the cutting blade relatively along the planned division line, The system comprises a controller for controlling the holding table and the cutting unit, The cutting unit further comprises an ultrasonic transducer capable of vibrating the cutting blade at a frequency in the ultrasonic band, The aforementioned controller, By vibrating the cutting blade at an ultrasonic frequency and rotating the cutting blade in a down-cut direction from the first surface to the second surface, the substrate is cut along the planned division line, and a cutting groove that does not reach the second surface is formed on the first surface. After the cutting groove is formed, the cutting blade is rotated in an up-cut direction from the second surface toward the first surface to cut away the remaining portion of the planned division line in which the cutting groove was formed. Execute the process. [Effects of the Invention]
[0009] According to the present invention, chipping can be suppressed while shortening the cutting time. [Brief explanation of the drawing]
[0010] [Figure 1] Figure 1 is a perspective view of the substrate. [Figure 2] Figure 2 is a front view of the substrate to illustrate each side of the substrate. [Figure 3] Figure 3 is a perspective view of the circuit board unit. [Figure 4] Figure 4 is a perspective view of a cutting machine according to one embodiment of the present invention. [Figure 5] Figure 5 is an exploded perspective view of the cutting unit of the cutting machine. [Figure 6] Figure 6 is a partial cross-sectional side view of the cutting unit. [Figure 7] Figure 7 is a perspective view showing the cutting process of a substrate by a cutting unit. [Figure 8] Figure 8 is a flowchart of the chip manufacturing method. [Figure 9] Figure 9 is a diagram illustrating the holding step. [Figure 10] Figures 10(A) and (B) illustrate the cutting groove formation step. [Figure 11] Figure 11 illustrates the cutting groove and fractured layer formed by the cutting groove formation step. [Figure 12](A) and (B) of FIG. 12 are diagrams for explaining the first division step. [Figure 13] FIG. 13 is a partial cross-sectional view of the substrate after the first division step. [Figure 14] (A) and (B) of FIG. 14 are diagrams for explaining the second division step. [Figure 15] FIG. 15 is a top view of a plurality of chips manufactured through the first division step and the second separation step. [Figure 16] FIG. 16 is a top view of a cutting device 20 of a modified example in which two cutting units 40 are provided. [Figure 17] FIG. 17 is a side view of the cutting device 20 of the modified example. [Embodiments for Carrying Out the Invention]
[0011] Hereinafter, an embodiment of a method for manufacturing a chip and a cutting device of the present invention will be described based on the accompanying drawings. The method for manufacturing a chip of the present invention is a method for manufacturing a plurality of chips by dividing a substrate. First, the substrate will be described with reference to FIGS. 1 and 2.
[0012] [Substrate] FIG. 1 is a perspective view of a substrate 1. FIG. 2 is a front view of the substrate 1 for explaining each surface of the substrate 1. The substrate 1 is a wafer having a disk shape and is formed of, for example, a semiconductor material. The substrate 1 is, for example, a gallium oxide (Ga2O3) substrate, and more specifically, a β-type gallium oxide (β-Ga2O3) substrate.
[0013] As shown in FIG. 1, the substrate 1 has a front surface 1a and a back surface 1b opposite to the front surface 1a. Further, an orientation flat OF indicating a crystal orientation is formed on the outer peripheral portion of the substrate 1.
[0014] As shown in Figure 2, the substrate 1, formed from β-type gallium oxide which has a monoclinic crystal structure, has a surface 1a that is the (001) plane, a plane parallel to the direction in which the orientation flat OF extends that is the (100) plane, and a plane perpendicular to the direction in which the orientation flat OF extends that is the (010) plane. The direction perpendicular to the (010) plane is the
[0010] direction, and the direction perpendicular to the (100) plane is the
[0100] direction. In the following explanation, equivalent planes may be represented collectively using curly braces {}, and equivalent directions may be represented collectively using angle brackets <>.
[0015] The substrate 1 has cleavage planes at the (100) plane and the (001) plane. Therefore, when the cutting device 20 (see Figure 4), which will be described later, cuts the substrate 1 along the (010) plane perpendicular to these cleavage planes, the substrate 1 is prone to cleavage along the (100) plane and the (001) plane, resulting in chipping on the cut end surface.
[0016] Returning to Figure 1, multiple division lines (also called streets) 3 are set in a grid pattern on surface 1a. The grid-like division lines 3 are formed by multiple division lines 3 extending in the
[0100] direction and multiple division lines 3 extending in the
[0010] direction. Devices 5 such as MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) and IGBTs (Insulated Gate Bipolar Transistors) are provided in each of the rectangular regions demarcated by the multiple division lines 3.
[0017] The type, quantity, shape, structure, size, and arrangement of device 5 are not particularly limited. A predetermined key pattern (not shown) is formed on the surface 1a side of substrate 1, which is used to identify the position of the planned division line 3.
[0018] [Circuit board unit] Figure 3 is a perspective view of the substrate unit 10. When processing the substrate 1, the substrate 1 is integrated with a metal, annular frame 13 by a circular tape (dicing tape) 11 made of a material such as resin. In other words, the substrate unit 10 is constructed by integrating the substrate 1 with the frame 13 via the tape 11.
[0019] The frame 13 has a circular opening 13a that is larger than the diameter of the substrate 1. In the substrate unit 10, tape 11 is attached to the back surface 1b of the substrate 1, which is placed in the opening 13a so that its surface 1a is exposed, and to one side of the frame 13.
[0020] The tape 11 has a diameter larger than the opening 13a of the frame 13. The tape 11 is a resin film, for example, in which an adhesive layer is laminated on a base layer made of resin, and is a substantially transparent film that transmits visible light and ultraviolet light substantially. The base layer is made of a resin such as polyolefin (PO), polyvinyl chloride (PVC), or polyethylene terephthalate (PET), and the adhesive layer is made of a resin such as acrylic or epoxy. The adhesive layer is, for example, an ultraviolet-curable resin and is provided over the entire surface of one side of the base layer. The ultraviolet-curable resin has relatively strong adhesive strength before being irradiated with ultraviolet light, but once irradiated with ultraviolet light (UV), the adhesive strength decreases.
[0021] Furthermore, the tape 11 does not necessarily need to have an adhesive layer in the area that is in contact with the substrate 1. In this case, the substrate 1 is attached to the tape 11 by thermal bonding or the like without using an adhesive layer.
[0022] [Cutting equipment] Next, a cutting apparatus according to one embodiment of the present invention will be described with reference to Figures 4 to 7.
[0023] Figure 4 is a perspective view of a cutting apparatus 20 according to one embodiment of the present invention. Figure 5 is an exploded perspective view of the cutting unit 40 of the cutting apparatus 20. Figure 6 is a partial cross-sectional side view of the cutting unit 40. Figure 7 is a perspective view showing the cutting of the substrate 1 by the cutting unit 40.
[0024] The substrate unit 10 is transported to the cutting device 20 and then cut along each planned division line 3. As shown in Figure 4, the X-axis direction (machining feed direction), Y-axis direction (indexing feed direction), and Z-axis direction (height direction, up and down direction, cutting feed direction) are orthogonal to each other.
[0025] The cutting apparatus 20 comprises a base 21 that supports each component, a chuck table (holding table) 30 that holds the substrate 1, a cutting unit 40 that cuts the substrate 1 held by the chuck table 30, and a controller 90 that controls the chuck table 30 and the cutting unit 40.
[0026] A ball screw type X-axis movement unit 23 is provided on the upper surface of the base 21. The X-axis movement unit 23 has a pair of guide rails 231 arranged substantially parallel to each other in the X-axis direction.
[0027] A movable table 24 is slidably mounted on a pair of guide rails 231. A nut portion (not shown) is provided on the underside (bottom) of the movable table 24, and a screw shaft 232, which is positioned parallel to the X-axis direction, is rotatably connected to this nut portion.
[0028] A drive source 233, such as a stepping motor, is connected to one end of the screw shaft 232. By rotating the screw shaft 232 with the drive source 233, the movable table 24 moves in the X-axis direction. A cylindrical support base 24a is provided approximately in the center of the upper surface of the movable table 24.
[0029] A rectangular table cover 24b is provided above the support base 24a, and a chuck table 30 is provided on the upper surface of the table cover 24b. A drive source such as a motor is provided inside the support base 24a, and when the drive source is operated, the chuck table 30 rotates around a rotation axis that is substantially parallel to the Z-axis direction.
[0030] The chuck table 30 has a disc-shaped frame made of a metal material such as stainless steel. A disc-shaped recess, smaller in diameter than the frame, is formed on the upper part of the frame. A disc-shaped porous plate made of porous ceramics is fixed to the recess of the frame.
[0031] Negative pressure is transmitted to the porous plate from a suction source (not shown), such as a vacuum pump, through a predetermined channel (not shown) formed in the frame. The upper surface of the frame and the upper surface of the porous plate are substantially flush, forming a substantially flat holding surface 31.
[0032] The holding surface 31 is positioned approximately parallel to the XY plane. When the substrate unit 10 is placed on the chuck table 30, the substrate 1 is held in place by suction at the holding surface 31 via the tape 11.
[0033] Multiple clamp units 34 (four in the illustrated example) are arranged at equal intervals around the chuck table 30, along the circumferential direction of the chuck table 30. Each clamp unit 34 secures the frame 13 of the substrate unit 10 placed on the chuck table 30.
[0034] A ball screw type Y-axis movement unit 25 is further provided on the upper surface of the base 21. The Y-axis movement unit 25 has a pair of guide rails 251 arranged substantially parallel to each other in the Y-axis direction.
[0035] A movable block 26 is slidably mounted on a pair of guide rails 251. The movable block 26 has a horizontal plate portion 26a adjacent to the pair of guide rails 251. A nut portion (not shown) is provided on the lower side of the horizontal plate portion 26a.
[0036] A screw shaft 252, positioned approximately parallel to the Y-axis, is rotatably connected to the nut portion. A drive source 253, such as a stepping motor, is connected to one end of the screw shaft 252. By rotating the screw shaft 252 with the drive source 253, the moving block 26 moves in the Y-axis direction.
[0037] A vertical plate section 26b is provided on the upper surface of the horizontal plate section 26a. A Z-axis movement unit 27 is provided on one side of the vertical plate section 26b that is substantially parallel to the YZ plane. The Z-axis movement unit 27 has a pair of guide rails 271 arranged substantially parallel to the Z-axis direction. Note that only one guide rail 271 is shown in Figure 3.
[0038] A holder 28 is slidably mounted on a pair of guide rails 271. A nut portion (not shown) is provided on the back side of the holder 28, and a screw shaft (not shown) positioned approximately parallel to the Z-axis direction is rotatably connected to this nut portion.
[0039] A drive source 273, such as a stepping motor, is connected to the upper end of the screw shaft. By rotating the screw shaft with the drive source 273, the holder 28 moves in the Z-axis direction.
[0040] The cutting unit 40 includes a spindle housing 41 fixed to the holder 28, a spindle 42, a cutting blade 43 mounted on the tip of the spindle 42, and the aforementioned Y-axis movement unit 25 and Z-axis movement unit 27.
[0041] The spindle housing 41 has a cylindrical shape, with its longitudinal portion positioned approximately parallel to the Y-axis direction. The tip of the spindle housing 41 is open, and the tip 42a of the spindle 42 protrudes from it.
[0042] An imaging device 80 capable of imaging the substrate 1 is provided on the side of the spindle housing 41. Although not shown in the figures, the imaging device 80 is, for example, an infrared camera capable of imaging the substrate 1 using infrared light, and comprises one or more lenses, a light source such as an LED (Light Emitting Diode) that emits infrared light, and a solid-state image sensor capable of photoelectric conversion of infrared light.
[0043] The spindle 42 has a cylindrical shape, with its longitudinal portion positioned approximately parallel to the Y-axis direction. The spindle 42 is rotatably housed in the spindle housing 41. A rotational drive source, such as a motor, is provided near the base end of the spindle 42.
[0044] As shown in Figure 5, the tip 42a of the spindle 42 protrudes from the spindle housing 41. A cutting blade 43 is mounted on the tip 42a of the spindle 42.
[0045] The cutting blade 43 is configured as a hubless (washer-type) blade consisting of an annular cutting edge. However, the cutting blade 43 is not limited to a hubless type; it may also be a hub blade.
[0046] A circular through-hole 43c is formed in the radial center of the cutting blade 43. In the cutting blade 43, abrasive grains made of diamond, CBN (cubic boron nitride), etc. are fixed with a binder such as metal, ceramics, or resin.
[0047] A male thread is formed on the outer peripheral side of the tip 42a of the spindle 42. The through hole 44a of the mount 44 is inserted into the tip 42a of the spindle 42. After inserting the through hole 44a of the mount 44 into the tip 42a of the spindle 42, the mount 44 is fixed to the spindle 42 by fastening an annular fixing nut 52 to the male thread of the tip 42a of the spindle 42. The cutting blade 43 is mounted on the spindle 42 via the mount 44.
[0048] The mount 44 has a disc-shaped flange portion 46. The flange portion 46 has an annular projection 46a located on the outer circumference of the flange portion 46. The projection 46a protrudes to one side in the thickness direction of the flange portion 46.
[0049] A cylindrical first boss portion 48, smaller in diameter than the flange portion 46, is provided on one side of the flange portion 46 in the thickness direction. A cutting blade 43 or the like is positioned on the outer surface of the first boss portion 48.
[0050] A male thread is formed on the outer circumferential surface of the tip of the first boss portion 48. On the other side in the thickness direction of the flange portion 46, a cylindrical second boss portion 49 is provided, which has a smaller diameter than the flange portion 46 and a larger diameter than the first boss portion 48.
[0051] The through hole 44a of the mount 44 is formed across the flange portion 46, the first boss portion 48, and the second boss portion 49, and fits into the spindle 42.
[0052] A disc-shaped retaining flange 50 is attached to the first boss portion 48. The retaining flange 50 has a protrusion 50a having approximately the same inner and outer diameter as the protrusion 46a of the flange portion 46.
[0053] The retaining flange 50 has an opening 50c in its radial center. The cutting blade 43 is sandwiched between the protrusion 50a of the retaining flange 50 and the protrusion 46a of the flange portion 46 of the mount 44, and the through portion 43c of the cutting blade 43 and the opening 50c of the retaining flange 50 are inserted into the first boss portion 48.
[0054] With the cutting blade 43 and retaining flange 50 positioned on the outer circumferential surface of the first boss portion 48, an annular fixing nut 54 is fastened to the male thread of the first boss portion 48. As a result, the cutting blade 43 is sandwiched between the flange portion 46 and the retaining flange 50 and fixed to the tip of the spindle 42.
[0055] The cutting unit 40 further includes an ultrasonic transducer 60 capable of vibrating the cutting blade 43 at a frequency in the ultrasonic band (for example, 20 kHz to 500 kHz). The ultrasonic transducer 60 has an annular shape and is provided inside the radial protrusion 46a of the flange portion 46 of the mount 44, and inside the radial protrusion 50a of the retaining flange 50.
[0056] Each ultrasonic transducer 60 in this embodiment is electrostrictive and has an annular piezoelectric body 61. The piezoelectric body 61 is made of a piezoelectric ceramic such as barium titanate or lead zirconate titanate. A pair of electrodes 63 and 64 are provided on both sides of the annular piezoelectric body 61 so as to sandwich the piezoelectric body 61. In addition to electrical contact between the pair of electrodes 63 and 64, an insulating film 65 is provided to prevent electrical contact between the pair of electrodes 63 and 64 and the flange portion 46.
[0057] Inside the mount 44, wiring 68 and 69 are provided and connected to the electrodes 63 and 64 of the ultrasonic transducer 60, respectively, via lead wires 66. Power is supplied to the wiring 68 and 69 inside the mount 44 from the AC power supply unit 78 via the rotary transformer 70. The rotary transformer 70 has a power receiving unit 72 provided on the second boss portion 49 of the mount 44 and a power supply unit 74 provided on the tip of the spindle housing 41.
[0058] The power receiving unit 72 includes an annular core and a coil wound around the core. One end of the coil is connected to wiring 68, and the other end of the coil is connected to wiring 69. The power supply unit 74 also includes an annular core and a coil.
[0059] The power supply unit 74 is connected to an AC power supply unit 78, such as a high-speed bipolar power supply, via wiring 75 and 76. A signal generator 79 that controls the frequency of the supplied AC voltage is also connected to the AC power supply unit 78. When power is supplied from the AC power supply unit 78 to the pair of electrodes 63 and 64 via the rotary transformer 70, the piezoelectric body 61 vibrates so as to expand and contract along the radial direction of the mount 44 and the retaining flange 50.
[0060] In Figure 6, there is a gap between the ultrasonic transducer 60 and the cutting blade 43, but in reality, the ultrasonic transducer 60 and the cutting blade 43 are in contact via a component not shown. The mount 44, the retaining flange 50, and the cutting blade 43 all vibrate due to the vibration of the piezoelectric element 61.
[0061] In particular, the piezoelectric element 61 of this embodiment vibrates in the radial direction of the cutting blade 43, rather than in the thickness direction of the cutting blade 43. The amplitude of the cutting blade 43 is set to, for example, 5.0 μm.
[0062] The controller 90 controls the operation of the chuck table 30, cutting unit 40, X-axis movement unit 23, Y-axis movement unit 25, Z-axis movement unit 27, imaging device 80, AC power supply unit 78, and signal generator 79, etc.
[0063] The controller 90 is composed of a computer that includes a processor (processing unit), such as a CPU (Central Processing Unit), and memory (storage device). The memory includes main memory such as DRAM (Dynamic Random Access Memory), SRAM (Static Random Access Memory), and ROM (Read Only Memory), and auxiliary storage such as flash memory, hard disk drive, and solid-state drive. Software containing predetermined programs is stored in the auxiliary storage device. The functions of the controller 90 are realized by operating the processor and other components according to this software.
[0064] [How to manufacture chips] Next, a method for manufacturing a chip according to one embodiment of the present invention will be described with reference to Figures 8 to 15.
[0065] Figure 8 is a flowchart of the chip manufacturing method. The chip manufacturing method comprises a holding step S1, a cutting groove forming step S2, a first division step S3, and a second division step S4. The cutting device 20 divides the substrate 1 into a plurality of chips 7 (see Figure 15) through each step. Each of these steps is carried out by the controller 90 controlling the chuck table 30 and the cutting unit 40.
[0066] (Holding step S1) As shown in Figure 9, the holding step S1 involves holding the substrate 1 with the chuck table 30 so that the surface surface 1a is exposed. Specifically, in the holding step S1, the substrate unit 10 is placed on the chuck table 30. The back surface 1b of the substrate 1 is then held by suction on the holding surface 30a of the chuck table 30 via the tape 11, and the frame 13 is fixed by the clamp unit 34.
[0067] At this time, the surface 1a of the substrate 1 is exposed upwards. In this state, the controller 90 obtains an image of the surface 1a by imaging the surface 1a with the imaging device 80. Since the distance from the key pattern on the surface 1a to the division line 3 is predetermined, the controller 90 uses the coordinates of the key pattern included in the image of the surface 1a to detect the position of the division line 3 in the XY plane.
[0068] (Cutting groove formation step S2) Figure 10(A) is a diagram illustrating the cutting groove formation step S2, and Figure 10(B) is a diagram illustrating the cutting direction of the substrate 1 in the cutting groove formation step S2. Figure 11 is a diagram illustrating the cutting groove 1c and crushed layer 1d formed by the cutting groove formation step S2.
[0069] After detecting the position of the planned division line 3, the controller 90, <100> The orientation of the substrate 1 is adjusted by rotating the chuck table 30 so that the planned division line 3, which extends in the direction, is parallel to the X-axis direction. <100> The directions include the
[0100] direction and the [-100] direction, which is opposite to the
[0100] direction. <100> The direction is perpendicular to the {100} plane, which is the cleavage plane of substrate 1.
[0070] The cutting groove forming step S2 involves rotating the cutting blade 43 in a down-cut direction from the surface 1a to the back surface 1b while vibrating the cutting blade 43 at an ultrasonic frequency, <100> The substrate 1 is cut along the planned division line 3 that extends in the direction, forming a cutting groove 1c on the surface 1a that does not reach the back surface 1b.
[0071] To explain in more detail, the controller 90 controls the cutting blade 43 <100> The cutting blade 43 is positioned on the extension of the planned division line 3 that extends in the direction, and its lower end is positioned at a predetermined depth between the surface 1a and the back surface 1b. The controller 90 then rotates and vibrates the cutting blade 43 while supplying a cutting fluid such as pure water, and moves the chuck table 30 along the X-axis direction. The relative feed rate of the cutting blade 43 with respect to the substrate 1 is, for example, 6 mm / s. As a result, the cutting blade 43 cuts the substrate 1 <100> Cutting is performed along the planned division line 3 in the direction. Note that in Figure 10 (B), the cutting blade 43 is <100> The example shown involves moving the cutting blade relatively along the
[0100] direction, but the cutting blade 43 may also be moved relatively along the [-100] direction.
[0072] Once cutting along one planned division line 3 is complete, the controller 90 moves the cutting blade 43 in the indexing feed direction and positions it on the extension of the adjacent planned division line 3 to perform the cutting groove formation step S2.
[0073] In the cutting groove formation step S2, a cutting groove 1c is formed in the substrate 1 while the cutting blade 43 is vibrated at an ultrasonic frequency. As shown in Figure 11, a crushed layer 1d is formed in the remaining portion 1e (the bottom of the cutting groove 1c).
[0074] (First division step S3) Figure 12(A) is a diagram illustrating the first division step S3, and Figure 12(B) is a diagram illustrating the cutting direction of the substrate 1. Figure 13 is a partial cross-sectional view of the substrate 1 after the first division step S3.
[0075] The first division step S3 is performed after the cutting groove forming step S2 by rotating the cutting blade 43 in an up-cutting direction from the back surface 1b to the front surface 1a of the substrate 1. <100> The remaining portion 1e of the planned division line 3, which extends in the direction, is cut.
[0076] To explain in more detail, the controller 90 controls the cutting blade 43 <100> The cutting blade 43 is positioned on the extension of the planned division line 3 that extends in the direction, and the lower end of the cutting blade 43 is positioned at a depth beyond the back surface 1b of the substrate 1. Then, the controller 90 rotates and vibrates the cutting blade 43 while supplying cutting fluid, and moves the chuck table 30 along the X-axis direction. The relative feed rate of the cutting blade 43 to the substrate 1 is, for example, 3 mm / s. As a result, the cutting blade 43 cuts the substrate 1 <100> Cut along the planned division line 3 that extends in the direction, <100> The substrate 1 is divided by cutting the remaining portion 1e of the planned division line 3 that extends in the direction. Note that in Figure 12 (B), the cutting blade 43 is <100> Although the example shown involves relative movement along the [-100] direction, the cutting blade 43 may also be moved relatively along the
[0100] direction. Furthermore, while the feed direction of the cutting blade 43 shown in Figure 12 is the opposite direction to the feed direction in the cutting groove formation step S2, it may also be the same direction as the feed direction in the cutting groove formation step S2.
[0077] Once cutting along one planned division line 3 is complete, the controller 90 moves the cutting blade 43 in the indexing feed direction and positions it on the extension of the adjacent planned division line 3 to perform the first division step S3.
[0078] In the first division step S3, the controller 90 positions the lower end of the cutting blade 43 at a depth slightly exceeding the back surface 1b of the substrate 1, so that the substrate 1 is cut without penetrating the tape 11.
[0079] (Second division step S4) Figure 14(A) is a diagram illustrating the second division step S4, and Figure 14(B) is a diagram illustrating the cutting direction of the substrate 1.
[0080] The second division step S4 is performed after the first division step S3, on substrate 1 <010> The substrate 1 is cut by rotating the cutting blade 43 in the up-cut direction while vibrating it at an ultrasonic frequency along the planned division line 3 that extends in the direction. <010> In directional cutting, the cutting blade 43 can be cut in one step without performing the cutting groove forming step S2. <100> The substrate 1 is cut along the planned division line 3 that extends in the direction. <010> The directions include the
[0010] direction and the [0-10] direction which is opposite to the
[0010] direction. <010> The direction is parallel to the {100} plane, which is the cleavage plane of substrate 1.
[0081] To explain in more detail, controller 90 is, <010> The orientation of the substrate 1 is adjusted by rotating the chuck table 30 by 90 degrees so that the planned division line 3 extending in the direction is parallel to the X-axis direction. Then the controller 90 moves the cutting blade 43 <010> The cutting blade 43 is positioned on the extension of the planned division line 3 that extends in the direction, and the lower end of the cutting blade 43 is positioned at a depth beyond the back surface 1b of the substrate 1. Then, the controller 90 rotates and vibrates the cutting blade 43 while supplying cutting fluid, and moves the chuck table 30 along the X-axis direction. The relative feed rate of the cutting blade 43 to the substrate 1 is, for example, 20 mm / s. As a result, the cutting blade 43 cuts the substrate 1 <010> Cutting is performed along the planned division line 3 that extends in the direction.
[0082] Once cutting along one planned division line 3 is complete, the controller 90 moves the cutting blade 43 in the indexing feed direction and positions it on the extension of the adjacent planned division line 3 to perform the second division step S4.
[0083] In the second division step S4, the controller 90 rotates the cutting blade 43 while activating the ultrasonic transducer 60, but it may also rotate the cutting blade 43 without activating the ultrasonic transducer 60.
[0084] In this way <100> Direction and <010> By cutting the substrate 1 along the planned division line 3 that extends in the direction, multiple chips 7 are manufactured, as shown in Figure 15.
[0085] Next, the effects and advantages of the manufacturing method of the chip 7 of this embodiment, as described above, will be explained.
[0086] As mentioned above, the substrate 1, formed from β-type gallium oxide which has a monoclinic crystal structure, has {100} and {001} planes as cleavage planes (see Figure 2). Therefore, the cutting blade 43 cuts along the {010} plane (in other words, <100> When the substrate 1 is divided along the direction, the substrate 1 is cleaved along the {100} plane and the {001} plane, making it prone to chipping on the cut edges.
[0087] If the cutting groove forming step S2 is not performed and the cutting blade 43 is cut in one go <100> When cutting the substrate 1 along the planned division line 3 that extends in the direction, the feed rate of the cutting blade 43 must be sufficiently slowed to prevent chipping. Specifically, the controller 90, <100> The cutting blade 43 is positioned on the extension of the planned division line 3 that extends in the direction, and the lower end of the cutting blade 43 is positioned at a depth beyond the back surface 1b of the substrate 1. The controller 90 then rotates and vibrates the cutting blade 43 while supplying cutting fluid to the cutting blade 43, and moves the chuck table 30 along the X-axis direction. <100> When cutting in a direction in a single operation, the relative feed rate of the cutting blade 43 to the substrate 1 must be sufficiently slow, for example, 1 mm / s, which results in a longer cutting time.
[0088] In the manufacturing method of the chip 7 of this embodiment, the cutting blade 43 <100> When cutting the substrate 1 along the planned division line 3 extending in the direction, the cutting groove formation step S2 and the first division step S3 are performed to cut the substrate 1 in stages. Since the first division step S3 cuts the remaining portion 1e after the cutting groove 1c is formed in the cutting groove formation step S2, not only is the occurrence of chipping suppressed, but the feed rate of the cutting blade 43 in each step S2 and S3 can be increased and the cutting time can be shortened compared to when the substrate 1 is cut in one go with the cutting blade 43.
[0089] Furthermore, although chipping is likely to occur when dividing the substrate 1 in the first division step S3, in the cutting groove formation step S2 performed in advance, the cutting blade 43 is vibrated at an ultrasonic frequency to form the cutting groove 1c, so a crushed layer 1d is formed in the remaining portion 1e, and the cutting resistance in the first division step S3 can be reduced. Moreover, in the first division step S3, the remaining portion 1e is cut with the rotation direction of the cutting blade 43 set to the up-cut direction, so the occurrence of chipping is further suppressed.
[0090] Thus, according to the manufacturing method of the chip 7 of this embodiment, even when cutting a substrate 1 that has cleavage that makes it easy to cleave along a specific surface, chipping can be suppressed and the cutting time can be shortened.
[0091] Here, it is preferable that the depth of the cutting groove 1c formed in the cutting groove formation step S2 is greater than half the thickness from the surface 1a to the back surface 1b of the substrate 1. By providing a sufficient depth for the cutting groove 1c, the runout of the cutting blade 43 in the cutting groove formation step S2 can be suppressed, and the machining accuracy can be improved.
[0092] Furthermore, it is preferable that the feed rate of the cutting blade 43 in the groove formation step S2 is faster than the feed rate in the first division step S3. Since the groove formation step S2 forms the groove 1c but does not divide the substrate 1, chipping is relatively less likely to occur. For this reason, the feed rate in the groove formation step S2 can be increased, thereby shortening the cutting time of the substrate 1. However, the feed rate of the cutting blade 43 in the groove formation step S2 is not limited to this, and may be equal to the feed rate in the first division step S3, or slower than the feed rate in the first division step S3.
[0093] Furthermore, in the first splitting step S3, it is preferable to rotate the cutting blade 43 without activating the ultrasonic transducer 60 to cut the substrate 1. This prevents excessive damage to the crystal of the substrate 1 due to the vibration of the cutting blade 43. However, in the first splitting step S3, the controller 90 may rotate the cutting blade 43 while activating the ultrasonic transducer 60.
[0094] Also, the substrate 1 <010> Since cutting in this direction is less likely to cause chipping, the second division step S4 is performed without forming cutting grooves. That is, the substrate 1 <010> In this method, the cutting groove formation step S2 is omitted, and the substrate 1 is cut and divided in one step in the second division step S4. This reduces the cutting time for the substrate 1.
[0095] (modified version) Figure 16 is a top view of a modified cutting device 20 in which multiple cutting units 40 (two in this example) are provided. Figure 17 is a side view of the modified cutting device 20.
[0096] The cutting apparatus 20 of the embodiment described above comprises one cutting unit 40 (cutting blade 43), and the cutting groove formation step S2, the first division step S3, and the second division step S4 are performed with one cutting blade 43. In the case of a modified cutting apparatus 20, which comprises two cutting units 40 (cutting blades 43), the cutting groove formation step S2 and the first division step S3 (or the second division step S4) may be performed with different cutting blades 43. In this case, the thicknesses of the two cutting blades 43 may be the same or different.
[0097] Although one embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to this embodiment. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these are also understood to naturally fall within the technical scope of the present invention. Furthermore, the components of the above embodiment may be combined in any way without departing from the spirit of the invention.
[0098] For example, the chip manufacturing method of the embodiment described above was performed on a substrate 1 which is a gallium oxide substrate, but it may also be performed on a substrate made of a material other than gallium oxide that has cleavage properties that make it easy to cleave along a specific plane.
[0099] This specification includes at least the following: The components and other elements corresponding to those in the embodiments described above are shown in parentheses as examples, but are not limited thereto.
[0100] (1) A method for manufacturing a chip in which a substrate (substrate 1) having a first surface (front surface 1a) and a second surface (back surface 1b) opposite to the first surface is divided along a plurality of division lines (division lines 3) set in a grid pattern, thereby manufacturing a plurality of chips (chips 7), A holding step (holding step S1) is performed in which the second surface of the substrate is held by a holding table (chuck table 30) such that the first surface of the substrate is exposed, A cutting groove forming step (cutting groove forming step S2) is performed by rotating a cutting blade (cutting blade 43) in a down-cut direction from the first surface toward the second surface while vibrating the cutting blade at a frequency in the ultrasonic band, thereby cutting the substrate along the planned division line and forming a cutting groove (cutting groove 1c) on the first surface that does not reach the second surface, The device comprises a first division step (first division step S3) in which, after the cutting groove forming step, the cutting blade is rotated in an up-cut direction from the second surface toward the first surface to cut the remaining portion (remaining portion 1e) of the division line in which the cutting groove has been formed, A method for manufacturing chips.
[0101] When cutting a substrate from the first surface to the second surface in one go with a cutting blade, it is necessary to slow down the cutting feed rate in order to suppress chipping on the cutting edge. According to (1), since the substrate is cut in stages by performing the cutting groove formation step and the first division step, not only is the occurrence of chipping suppressed, but the cutting time can be shortened by increasing the feed rate of the cutting blade in each step compared to when the substrate is cut in one go with a cutting blade. Furthermore, although chipping is likely to occur in the first splitting step, in the cutting groove formation step, the cutting blade is vibrated at an ultrasonic frequency while forming the cutting groove, so a crushed layer is formed in the remaining material, reducing the cutting resistance in the first splitting step. Moreover, in the first splitting step, the rotation direction of the cutting blade is set to the up-cut direction. With this configuration, the occurrence of chipping in the first splitting step can be further suppressed. As a result, a chip manufacturing method is realized that can suppress chipping while shortening the cutting time.
[0102] (2) A method for manufacturing a chip as described in (1), The cutting groove forming step and the first division step involve cutting the substrate along the planned division line that extends in a direction perpendicular to the cleavage surface of the substrate. A method for manufacturing chips.
[0103] According to (2), even when cutting a substrate with cleavage properties, chipping can be suppressed and cutting time can be shortened.
[0104] (3) A method for manufacturing a chip as described in (2), The device further comprises a second division step (second division step S4) in which the cutting blade is rotated in the up-cut direction along the planned division line extending in a direction parallel to the cleavage plane of the substrate, thereby cutting the substrate from the first surface to the second surface. A method for manufacturing chips.
[0105] According to (3), cutting in a direction parallel to the cleavage plane of the substrate is less likely to cause chipping, so the substrate can be divided without forming cutting grooves. Therefore, the cutting time can be shortened.
[0106] (4) A method for manufacturing a chip as described in (1), The substrate is a gallium oxide substrate. A method for manufacturing chips.
[0107] According to (4), a gallium oxide substrate having cleavage properties that make it easy to cleave along a specific surface can be cut while suppressing chipping and shortening the cutting time.
[0108] (5) A method for manufacturing a chip as described in (4), The first surface of the substrate is the {001} surface, The cutting groove forming step and the first division step are performed on the substrate <100> Cutting along the planned division line extending in the direction, A method for manufacturing chips.
[0109] According to (5), in a gallium oxide substrate <100> Although cutting in a directional direction is prone to chipping, <100> Since the cutting groove formation step and the first splitting step are performed along the direction, the occurrence of chipping can be suppressed.
[0110] (6) A method for manufacturing a chip as described in (5), The aforementioned substrate <010> The device further includes a second division step (second division step S4) in which the cutting blade is rotated in the up-cut direction along the planned division line extending in the direction, thereby cutting the substrate from the first surface to the second surface. A method for manufacturing chips.
[0111] According to (6), in a gallium oxide substrate <010> Cutting in this direction is less prone to chipping, allowing the substrate to be divided without forming cutting grooves. Therefore, cutting time can be reduced.
[0112] (7) A method for manufacturing a chip according to any one of (1) to (6), The depth of the cutting groove formed by the cutting groove forming step is greater than half the thickness of the substrate from the first surface to the second surface. A method for manufacturing chips.
[0113] According to (7), by providing a sufficient depth for the cutting groove, the runout of the cutting blade during the cutting groove formation step can be suppressed, thereby improving machining accuracy.
[0114] (8) A method for manufacturing a chip according to any one of (1) to (7), The feed rate of the cutting blade in the cutting groove forming step is faster than the feed rate in the first division step. A method for manufacturing chips.
[0115] According to (8), the cutting time of the substrate can be shortened by increasing the feed rate of the cutting groove formation step, in which chipping is relatively less likely to occur.
[0116] (9) A cutting device (cutting device 20) for manufacturing a plurality of chips (chips 7) by dividing a substrate (substrate 1) having a first surface (front surface 1a) and a second surface (back surface 1b) opposite to the first surface, along a plurality of division lines (division lines 3) set in a grid, A holding table (chuck table 30) that holds the second surface of the substrate so that the first surface of the substrate is exposed, A cutting unit (cutting unit 40) having a cutting blade (cutting blade 43), which cuts the substrate by moving the cutting blade relatively along the planned division line, The system includes a controller (controller 90) that controls the holding table and the cutting unit, The cutting unit further includes an ultrasonic transducer (ultrasonic transducer 60) capable of vibrating the cutting blade at a frequency in the ultrasonic band, The aforementioned controller, By vibrating the cutting blade at an ultrasonic frequency and rotating the cutting blade in a down-cut direction from the first surface to the second surface, the substrate is cut along the planned division line, and a cutting groove (cutting groove 1c) that does not reach the second surface is formed on the first surface. After the cutting groove is formed, the cutting blade is rotated in an up-cut direction from the second surface toward the first surface to cut the remaining portion (remaining portion 1e) of the planned division line in which the cutting groove has been formed. The process (cutting groove formation step S2, first division step S3) is performed. cutting equipment.
[0117] According to (9), similar to (1) above, chipping can be suppressed while shortening the cutting time. [Explanation of Symbols]
[0118] 1 circuit board 1a Surface (first surface) 1b Reverse side (second side) 1c cutting groove 1e Remaining portion Planned division into 3 lines 7 chips 20 Cutting equipment 30 Chuck Table (Holding Table) 40 cutting units 43 Cutting blades 60 Ultrasonic transducers 90 Controllers S1 Holding step S2 Cutting groove forming step S3 First split step S4 Second division step
Claims
1. A method for manufacturing chips, comprising dividing a substrate having a first surface and a second surface opposite to the first surface along a plurality of division lines set in a grid pattern, thereby manufacturing a plurality of chips, A holding step of holding the second surface of the substrate with a holding table so that the first surface of the substrate is exposed, A cutting groove forming step, in which the cutting blade is rotated in a down-cut direction from the first surface toward the second surface while vibrating the cutting blade at a frequency in the ultrasonic band, thereby cutting the substrate along the planned division line and forming a cutting groove on the first surface that does not reach the second surface, The process includes a first dividing step in which, after the cutting groove forming step, the cutting blade is rotated in an up-cut direction from the second surface toward the first surface to cut away the remaining portion of the dividing line in which the cutting groove has been formed. A method for manufacturing chips.
2. A method for manufacturing a chip according to claim 1, The cutting groove forming step and the first division step involve cutting the substrate along the planned division line that extends in a direction perpendicular to the cleavage surface of the substrate. A method for manufacturing chips.
3. A method for manufacturing a chip according to claim 2, The method further comprises a second division step of cutting the substrate from the first surface to the second surface by rotating the cutting blade in the up-cut direction along the planned division line extending in a direction parallel to the cleavage plane of the substrate. A method for manufacturing chips.
4. A method for manufacturing a chip according to claim 1, The substrate is a gallium oxide substrate. A method for manufacturing chips.
5. A method for manufacturing a chip according to claim 4, The first surface of the substrate is the {001} surface, The cutting groove forming step and the first division step are performed by cutting along the planned division line extending in the <100> direction of the substrate. A method for manufacturing chips.
6. A method for manufacturing a chip according to claim 5, The second division step further comprises rotating the cutting blade in the up-cut direction along the planned division line extending in the <010> direction of the substrate, thereby cutting the substrate from the first surface to the second surface. A method for manufacturing chips.
7. A method for manufacturing a chip according to any one of claims 1 to 6, The depth of the cutting groove formed by the cutting groove forming step is greater than half the thickness of the substrate from the first surface to the second surface. A method for manufacturing chips.
8. A method for manufacturing a chip according to any one of claims 1 to 6, The feed rate of the cutting blade in the cutting groove forming step is faster than the feed rate in the first division step. A method for manufacturing chips.
9. A cutting apparatus for manufacturing multiple chips by dividing a substrate, which has a first surface and a second surface opposite to the first surface, along a plurality of division lines set in a grid pattern, A holding table that holds the second surface of the substrate so that the first surface of the substrate is exposed, A cutting unit having a cutting blade, which cuts the substrate by moving the cutting blade relatively along the planned division line, The system comprises a controller for controlling the holding table and the cutting unit, The cutting unit further comprises an ultrasonic transducer capable of vibrating the cutting blade at a frequency in the ultrasonic band, The aforementioned controller, By vibrating the cutting blade at an ultrasonic frequency and rotating the cutting blade in a down-cut direction from the first surface toward the second surface, the substrate is cut along the planned division line, and cutting grooves that do not reach the second surface are formed on the first surface. After the cutting groove is formed, the cutting blade is rotated in an up-cut direction from the second surface toward the first surface to cut the remaining portion of the planned division line in which the cutting groove has been formed. Execute the process cutting equipment.