How to inspect chips

Abstract

To provide an inspection method that makes it possible to properly evaluate chips formed by dividing a workpiece.SOLUTION: The inspection method for chips includes the steps of: dividing a workpiece into a plurality of chips by processing the workpiece under predetermined dividing processing conditions; acquiring a side image representing a side surface of a chip by imaging the side surface of the chip; and inspecting the state of the chip by comparing an evaluation value extracted from the side image with a threshold value.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a chip inspection method for inspecting chips formed by dividing a workpiece. [Background technology]

[0002] The device chip manufacturing process uses a wafer in which devices are formed in multiple areas defined by multiple intersecting streets (planned division lines). By dividing this wafer along the streets, multiple device chips, each equipped with a device, are obtained. The device chips are incorporated into various electronic devices, such as mobile phones and personal computers.

[0003] A cutting device, for example, is used to divide the wafer. The cutting device includes a chuck table that holds the workpiece and a cutting unit that cuts the workpiece. The cutting unit has a built-in spindle, and an annular cutting blade is attached to the tip of the spindle. The wafer is held on the chuck table, and the cutting blade is rotated to cut into the wafer, cutting the wafer and dividing it into multiple device chips.

[0004] In recent years, developments have also been made in processes for dividing wafers using laser processing. For example, a laser beam that is transparent to the wafer is focused inside the wafer and scanned along the streets, forming a modified layer inside the wafer along the streets. The area of ​​the wafer where the modified layer is formed becomes more fragile than other areas. Therefore, when an external force is applied to a wafer with a modified layer formed, the modified layer acts as a dividing point, dividing the wafer along the streets.

[0005] After the wafer is divided, an inspection is conducted to check whether the die strength (bending strength) of each device chip meets a predetermined standard, and only device chips that meet the standard are mounted on products. Furthermore, if a device chip that does not meet the predetermined standard is formed, the wafer processing conditions are reviewed so that the die strength of device chips manufactured thereafter is maintained at a certain level or above.

[0006] When measuring the die strength of device chips, after dividing a wafer into multiple device chips, an operator must manually pick up each device chip using tweezers or similar and transport them repeatedly to a measuring device that measures the die strength. This makes device chip inspection time-consuming. Furthermore, manually transporting device chips can lead to variations in the placement of device chips or to the risk of accidentally damaging the device chips.

[0007] Therefore, a dedicated inspection device may be used to measure the flexural strength of a device chip. For example, Patent Document 1 discloses an inspection device (test device) that automatically performs a series of operations (pickup, transport, measurement, etc.) for measuring the flexural strength of a device chip. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent Publication No. 2021-5678 Summary of the Invention [Problem to be solved by the invention]

[0009] When chips obtained by dividing a workpiece such as a wafer are inspected by the above-mentioned inspection device, the chips are evaluated based on whether the value of the flexural strength measured by the inspection device is within a predetermined tolerance range. Chips whose flexural strength value is outside the tolerance range are excluded as defective chips from the chips to be used in products.

[0010] However, simply checking the die strength measured by an inspection device may not be sufficient to evaluate the actual die strength. For example, if the processing conditions for dividing the workpiece are not set appropriately, unintended processing marks may remain inside the die even if the die strength value is within the allowable range. Then, during the subsequent chip mounting process or after the die is incorporated into a product, the reduction in die strength due to the processing marks may become apparent, and the processing marks may cause the die to break when subjected to a sudden impact.

[0011] The present invention has been made in view of the above problems, and has as its object to provide a chip inspection method that enables appropriate evaluation of chips formed by dividing a workpiece. [Means for solving the problem]

[0012] According to one aspect of the present invention, the method includes a dividing step of dividing a workpiece into a plurality of chips by processing the workpiece under predetermined dividing processing conditions, an imaging step of capturing an image of the side surface of each chip to obtain a side image representing the side surface of each chip, and an inspection step of inspecting the state of each chip by comparing an evaluation value extracted from the side image with a threshold value. The dividing step includes a modified layer forming step of forming a modified layer inside the workpiece along the streets by irradiating a laser beam that is transparent to the workpiece along the streets, and an external force applying step of dividing the workpiece along the streets starting from the modified layer by applying an external force to the workpiece, and the evaluation value is a value corresponding to a gradation in a region representing the modified layer in the side image, or a value corresponding to a position of the modified layer shown in the side image. A method for testing a chip is provided.

[0013] According to another aspect of the present invention, there is provided a method for manufacturing a plurality of first workpieces under a plurality of processing conditions, thereby dividing the first workpieces into a plurality of first chips, a first imaging step for imaging the side surfaces of the first chips to obtain first side images representing the side surfaces of the first chips, a measuring step for measuring the bending strength of the first chips, a dividing processing condition setting step for setting the machining conditions among the plurality of processing conditions that can form the first chips with the highest bending strength as dividing processing conditions, and a method for manufacturing the first workpieces under the dividing processing conditions. A chip inspection method is provided, including a reference image setting step of setting the first side image representing the side of the chip as a reference image; a threshold setting step of setting a threshold for an evaluation value extracted from the reference image; a second division step of dividing a second workpiece into a plurality of second chips by processing the second workpiece under the division processing conditions; a second imaging step of acquiring a second side image representing the side of the second chip by imaging the side of the second chip; and an inspection step of inspecting the state of the second chip by comparing the evaluation value extracted from the second side image with the threshold. [Effects of the Invention]

[0015] In a chip inspection method according to one aspect of the present invention, the state of a chip is inspected based on an evaluation value extracted from a side image representing the side surface of the chip. This allows for a more detailed understanding of the state of the chip, which cannot be fully evaluated by measuring only the die strength of the chip, and enables appropriate quality evaluation of the chip obtained by dividing the workpiece. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1(A) is a perspective view showing a workpiece, and FIG. 1(B) is a perspective view showing the workpiece divided into a plurality of chips. [Figure 2] FIG. [Figure 3] FIG. 2 is a perspective view showing the inspection device with some of its components omitted. [Figure 4] FIG. 2 is a perspective view showing a pickup mechanism. [Figure 5] FIG. 5(A) is a perspective view showing a bottom surface observation mechanism, and FIG. 5(B) is a perspective view showing a bottom surface observation mechanism that holds the second support part of the arm. [Figure 6] FIG. 6(A) is a front view showing an imaging unit that images the bottom surface of a chip, and FIG. 6(B) is a front view showing an imaging unit that images the side surface of a chip. [Figure 7] FIG. 7(A) is a partial cross-sectional front view showing the imaging unit of the bottom surface observation mechanism, and FIG. 7(B) is a schematic diagram showing an interference objective lens. [Figure 8] FIG. 8(A) is a perspective view showing the chip inversion mechanism, FIG. 8(B) is a perspective view showing the chip inversion mechanism holding the chip, and FIG. 8(C) is a perspective view showing the chip inversion mechanism with the chip inverted. [Figure 9] FIG. 2 is a perspective view showing a measurement unit. [Figure 10] FIG. 2 is a perspective view showing a support unit. [Figure 11] FIG. [Figure 12] FIG. 2 is a cross-sectional view showing the measurement unit in a state where a tip is supported by a support unit. [Figure 13] FIG. 10 is a cross-sectional view showing the measurement unit in a state where the tip is in contact with the support portion of the support base. [Figure 14] FIG. 10 is a cross-sectional view showing the measurement unit in a state where the tip is broken. [Figure 15] 10 is a flowchart showing a first chip inspection method. [Figure 16] FIG. 2 is a partial cross-sectional front view showing the laser processing device. [Figure 17] FIG. 17(A) is a partial cross-sectional front view showing an expansion device, and FIG. 17(B) is a partial cross-sectional front view showing an expansion device for expanding a tape. [Figure 18] FIG. 10 is an image showing a side view of a chip. [Figure 19] 10 is a flowchart showing a second chip inspection method. [Figure 20]FIG. 20(A) is a perspective view showing a first workpiece used in the evaluation condition setting step, and FIG. 20(B) is a perspective view showing a second workpiece used in the evaluation step. [Figure 21] FIG. 2 is a block diagram showing an inspection device and a laser processing device. DETAILED DESCRIPTION OF THE INVENTION

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the accompanying drawings. First, an example of the structure of a workpiece and an inspection device that can be used in the chip inspection method according to this embodiment will be described.

[0018] <Example of workpiece configuration> 1(A) is a perspective view showing a workpiece 11. For example, the workpiece 11 is a disk-shaped wafer made of a semiconductor material such as single crystal silicon, and has a front surface (first surface) 11a and a back surface (second surface) 11b that are generally parallel to each other.

[0019] The workpiece 11 is divided into a plurality of rectangular regions by a plurality of streets (planned division lines) 13 arranged in a grid pattern so as to intersect with one another. Furthermore, devices 15 such as ICs (Integrated Circuits), LSIs (Large Scale Integration), LEDs (Light Emitting Diodes), MEMS (Micro Electro Mechanical Systems) devices, etc. are formed in each of the regions divided by the streets 13 on the front surface 11a of the workpiece 11.

[0020] However, there are no limitations on the material, shape, structure, size, etc. of the workpiece 11. For example, the workpiece 11 may be a substrate (wafer) made of a semiconductor other than silicon (GaAs, InP, GaN, SiC, etc.), glass, ceramics, resin, metal, etc. Furthermore, there are no limitations on the type, number, shape, structure, size, arrangement, etc. of the devices 15.

[0021] The workpiece 11 is processed by various processing devices such as a cutting device or a laser processing device, and divided along the streets 13. When the workpiece 11 is processed by the processing device, the workpiece 11 is supported by an annular frame 17 for ease of handling (transporting, holding, processing, etc.) the workpiece 11. The frame 17 is made of a metal such as SUS (stainless steel), and has a circular opening 17a at the center of the frame 17 that penetrates the frame 17 in the thickness direction. The diameter of the opening 17a is larger than the diameter of the workpiece 11.

[0022] Tape 19 is attached to workpiece 11 and frame 17. Tape 19 includes a circular film-like substrate and an adhesive layer (glue layer) provided on the substrate. For example, the substrate is made of a resin such as polyolefin, polyvinyl chloride, or polyethylene terephthalate, and the adhesive layer is made of an epoxy-, acrylic-, or rubber-based adhesive.

[0023] With the workpiece 11 placed inside the opening 17a of the frame 17, the center of the tape 19 is attached to the back surface 11b of the workpiece 11, and the outer periphery of the tape 19 is attached to the frame 17. As a result, the workpiece 11 is supported by the frame 17 via the tape 19, and a workpiece unit (frame unit) including the workpiece 11, the frame 17, and the tape 19 is formed.

[0024] 1(B) is a perspective view showing the workpiece 11 divided into a plurality of chips 21. By dividing the workpiece 11 along the streets 13, a plurality of chips 21 (device chips) each including a device 15 are manufactured. Specific examples of methods for dividing the workpiece 11 will be described later (see FIGS. 16, 17(A), and 17(B)).

[0025] Each of the multiple chips 21 will be peeled off from the tape 19 and picked up in a later process. For this reason, it is preferable that the tape 19 has a property that its adhesive strength decreases when subjected to a predetermined treatment. For example, the tape 19 includes an adhesive layer made of an ultraviolet-curable resin. In this case, by irradiating the tape 19 with ultraviolet light, the adhesive strength of the tape 19 to the chips 21 decreases, making it easier to peel the chips 21 from the tape 19.

[0026] <Example of inspection device configuration> Next, an example of the configuration of an inspection device (measuring device, testing device) that inspects chips 21 formed by dividing workpiece 11 will be described. FIG. 2 is a perspective view showing inspection device 2. FIG. 3 is a perspective view showing inspection device 2 with some of its components (a pickup mechanism 70 and a collet moving mechanism 80, which will be described later) omitted for ease of explanation. In FIGS. 2 and 3, the X-axis direction (first horizontal direction, left-right direction) and the Y-axis direction (second horizontal direction, front-rear direction) are mutually perpendicular. Furthermore, the Z-axis direction (vertical direction, height direction, up-down direction) is a direction perpendicular to the X-axis direction and the Y-axis direction.

[0027] The inspection device 2 includes a base 4 that supports the various components that make up the inspection device 2. As shown in FIG. 3, a rectangular opening 4a is provided at a corner on the front end side of the base 4. A cassette mounting table 6 that is raised and lowered by a lifting mechanism (not shown) is disposed inside the opening 4a. A cassette 8 that can accommodate a plurality of workpieces 11 is placed on the upper surface of the cassette mounting table 6. Note that in FIGS. 2 and 3, only the outline of the cassette 8 is shown by a dashed line.

[0028] The workpiece 11 (see FIG. 1(B)) divided into a plurality of chips 21 is accommodated in the cassette 8 while being supported by the frame 17. Before accommodating the workpiece 11 in the cassette 8, a process (such as irradiation with ultraviolet light) for reducing the adhesive strength of the tape 19 may be performed as necessary.

[0029] 3, a temporary placement mechanism 10 on which a workpiece 11 is temporarily placed is provided behind the cassette placement table 6. The temporary placement mechanism 10 includes a pair of guide rails 12 arranged generally parallel to each other. Each of the pair of guide rails 12 includes a first support surface 12a and a second support surface 12b that are generally parallel to the horizontal plane (XY plane).

[0030] Each of the first support surfaces 12a is disposed above the second support surfaces 12b so as to overlap the corresponding second support surfaces 12b. The pair of first support surfaces 12a and the pair of second support surfaces 12b each support the lower surface of the frame 17 that supports the workpiece 11. For example, the pair of first support surfaces 12a supports the workpiece 11 that has been carried out of the cassette 8, and the pair of second support surfaces 12b supports the workpiece 11 that is being carried into the cassette 8.

[0031] A frame fixing mechanism 14 is provided behind the temporary placement mechanism 10 to fix a frame 17 that supports the workpiece 11. The frame fixing mechanism 14 includes a frame support part 16 that supports the underside of the frame 17, and a frame presser part 18 that is arranged above the frame support part 16. The frame support part 16 and the frame presser part 18 are formed in an annular shape corresponding to the shape of the frame 17, and are arranged so as to overlap each other.

[0032] The frame support part 16 is configured to be movable (up and down) along the Z-axis direction. When the frame support part 16 is moved upward while the frame 17 is supported by the frame support part 16, the upper surface of the frame 17 comes into contact with the frame retainer part 18. As a result, the frame 17 is sandwiched and fixed between the frame support part 16 and the frame retainer part 18. At this time, by determining whether the frame support part 16 and the frame retainer part 18 are electrically connected via the frame 17, it can be confirmed whether the frame 17 is properly fixed by the frame fixing mechanism 14.

[0033] A transport mechanism 20 is provided above the temporary placement mechanism 10 and the frame support part 16 to transport the workpiece 11 between the cassette 8 and the frame fixing mechanism 14. The transport mechanism 20 is configured to be movable along the Y-axis direction and the Z-axis direction, and includes a first gripping part 22a and a second gripping part 22b that grip the frame 17 from above and below. The first gripping part 22a is provided at the front end of the transport mechanism 20, and the second gripping part 22b is provided at the rear end of the transport mechanism 20.

[0034] When carrying out the workpiece 11 from the cassette 8, the transfer mechanism 20 is moved along the Y-axis direction toward the temporary placement mechanism 10 while the first gripping parts 22a grip the end of the frame 17 housed in the cassette 8. This causes the workpiece 11 to be pulled out of the cassette 8 and placed on the pair of first support surfaces 12a. Thereafter, the frame 17 is released from the gripping by the first gripping parts 22a.

[0035] Next, with the end of the frame 17 being gripped by the second gripping portion 22b, the transport mechanism 20 is moved along the Y-axis direction toward the frame fixing mechanism 14. As a result, the frame 17 is transported between the frame support portion 16 and the frame pressing portion 18 and is supported by the frame support portion 16.

[0036] A notch 18a (see FIG. 3) is provided at the front end of the frame retainer 18. The notch 18a is sized to allow the transport mechanism 20 to pass through. This prevents contact between the transport mechanism 20 and the frame retainer 18 when the frame 17 is transported to the frame fixing mechanism 14.

[0037] Thereafter, the frame 17 is released from the grip of the second gripping portion 22b, and the frame support portion 16 is moved upward, whereby the frame 17 is sandwiched and fixed between the frame support portion 16 and the frame pressing portion .

[0038] A movement mechanism 30 that adjusts the position of the frame fixing mechanism 14 is connected to the frame fixing mechanism 14. The movement mechanism 30 includes an X-axis movement mechanism 32 that moves the frame fixing mechanism 14 along the X-axis direction, and a Y-axis movement mechanism 42 that moves the frame fixing mechanism 14 along the Y-axis direction. The X-axis movement mechanism 32 and the Y-axis movement mechanism 42 adjust the position of the frame fixing mechanism 14 in the horizontal direction.

[0039] The X-axis movement mechanism 32 includes a pair of X-axis guide rails 34 arranged along the X-axis direction on the base 4. An X-axis ball screw 36 is provided between the pair of X-axis guide rails 34 and arranged generally parallel to the X-axis guide rails 34. An X-axis pulse motor 38 that rotates the X-axis ball screw 36 is connected to the end of the X-axis ball screw 36.

[0040] A moving plate 40 is slidably mounted on the pair of X-axis guide rails 34. A nut portion (not shown) is provided on the lower surface (back surface side) of the moving plate 40, and an X-axis ball screw 36 is threadedly engaged with this nut portion. When the X-axis pulse motor 38 rotates the X-axis ball screw 36, the moving plate 40 moves in the X-axis direction along the X-axis guide rails 34.

[0041] The Y-axis movement mechanism 42 includes a pair of Y-axis guide rails 44 arranged along the Y-axis direction on the moving plate 40. A Y-axis ball screw 46 is provided between the pair of Y-axis guide rails 44 and arranged generally parallel to the Y-axis guide rails 44. A Y-axis pulse motor 48 that rotates the Y-axis ball screw 46 is connected to the end of the Y-axis ball screw 46.

[0042] A frame fixing mechanism 14 is slidably mounted on a pair of Y-axis guide rails 44. A nut portion (not shown) is provided on the underside of the frame fixing mechanism 14, and a Y-axis ball screw 46 is threadedly engaged with this nut portion. When the Y-axis ball screw 46 is rotated by a Y-axis pulse motor 48, the frame fixing mechanism 14 moves in the Y-axis direction along the pair of Y-axis guide rails 44.

[0043] A rectangular opening 4b is provided on the upper surface of the base 4 between the pair of X-axis guide rails 34. A cylindrical push-up mechanism 50 is provided inside the opening 4b to push up chips 21 (see FIG. 1(B)) formed by dividing the workpiece 11. An elevating mechanism (not shown), such as an air cylinder, is connected to the push-up mechanism 50 to move (lift) the push-up mechanism 50 along the Z-axis direction.

[0044] With the frame 17 fixed by the frame fixing mechanism 14, the frame fixing mechanism 14 is moved along the X-axis direction by the moving mechanism 30, thereby positioning the workpiece 11 directly above the opening 4b. When the push-up mechanism 50 is raised in this state, the tip 21 positioned at a position overlapping the push-up mechanism 50 is pushed up. This makes it easier to tip up a specific tip 21. The dimensions of the push-up mechanism 50 are adjusted appropriately depending on the size of the tip 21.

[0045] An imaging unit 60 that images the workpiece 11 is provided above the push-up mechanism 50. The imaging unit 60 is disposed in a position where it can image the entire workpiece 11 placed above the opening 4b. Based on the image acquired by imaging the workpiece 11 with the imaging unit 60, the position of the frame fixing mechanism 14 is adjusted so that a predetermined tip 21 is positioned directly above the push-up mechanism 50. This allows the tip 21 and the push-up mechanism 50 to be aligned.

[0046] The chip 21 pushed up by the push-up mechanism 50 is picked up by a pickup mechanism 70 shown in Fig. 2. The pickup mechanism 70 includes a collet 76 that picks up the chip 21 pushed up by the push-up mechanism 50. In addition, a collet moving mechanism 80 that adjusts the position of the collet 76 is connected to the pickup mechanism 70.

[0047] 4 is a perspective view showing the pickup mechanism 70. The pickup mechanism 70 includes a moving block 72 coupled to the collet moving mechanism 80, and a columnar arm 74 connecting the collet 76 and the collet moving mechanism 80. The arm 74 is disposed along the X-axis direction from the moving block 72 toward the opposite side from the collet moving mechanism 80. The arm 74 also includes a columnar first support portion 74a connected to the collet moving mechanism 80 via the moving block 72, and a second support portion 74b protruding downward from the tip of the first support portion 74a.

[0048] The first support portion 74a and the second support portion 74b are configured to be connectable and separable to each other. For example, the first support portion 74a and the second support portion 74b are detachably connected to each other via an attachment / detachment mechanism such as a tool changer.

[0049] A collet 76 that holds the tip 21 (see FIG. 1(B)) is fixed to the lower end side of the second support portion 74b. The lower surface of the collet 76 is a flat surface that is roughly parallel to the horizontal plane (XY plane) and constitutes a suction surface 76a that sucks the tip 21. For example, the suction surface 76a is connected to a suction source (not shown) such as an ejector via a suction path (not shown) formed inside the collet 76. With the tip 21 in contact with the suction surface 76a, the suction force (negative pressure) of the suction source is applied to the suction surface 76a, whereby the tip 21 is sucked and held by the collet 76.

[0050] 2, the collet moving mechanism 80 includes a Y-axis moving mechanism 82 that moves the pickup mechanism 70 along the Y-axis direction, and a Z-axis moving mechanism 92 that moves the pickup mechanism 70 along the Z-axis direction. The Y-axis moving mechanism 82 and the Z-axis moving mechanism 92 adjust the position of the collet 76 in the Y-axis direction and the Z-axis direction.

[0051] The Y-axis movement mechanism 82 includes a pair of Y-axis guide rails 84 arranged along the Y-axis direction. A Y-axis ball screw 86 is provided between the pair of Y-axis guide rails 84 and arranged generally parallel to the Y-axis guide rails 84. A Y-axis pulse motor 88 that rotates the Y-axis ball screw 86 is connected to the end of the Y-axis ball screw 86.

[0052] A moving plate 90 is slidably mounted on the pair of Y-axis guide rails 84. A nut portion (not shown) is provided on the moving plate 90, and a Y-axis ball screw 86 is threadedly engaged with this nut portion. When the Y-axis ball screw 86 is rotated by a Y-axis pulse motor 88, the moving plate 90 moves in the Y-axis direction along the Y-axis guide rails 84.

[0053] The Z-axis movement mechanism 92 includes a pair of Z-axis guide rails 94 arranged along the Z-axis direction on the surface of the moving plate 90. A Z-axis ball screw 96 is provided between the pair of Z-axis guide rails 94 and arranged generally parallel to the Z-axis guide rails 94. A Z-axis pulse motor 98 that rotates the Z-axis ball screw 96 is connected to the end of the Z-axis ball screw 96.

[0054] A moving block 72 of the pickup mechanism 70 is slidably mounted on a pair of Z-axis guide rails 94. A nut portion (not shown) is provided on the moving block 72, and a Z-axis ball screw 96 is threadedly engaged with this nut portion. When the Z-axis ball screw 96 is rotated by a Z-axis pulse motor 98, the moving block 72 moves in the Z-axis direction along the Z-axis guide rails 94.

[0055] The chip 21 (see FIG. 1(B)) pushed up by the push-up mechanism 50 is picked up by the collet 76 of the pickup mechanism 70. Specifically, first, the workpiece 11 fixed by the frame fixing mechanism 14 is moved by the moving mechanism 30 and placed on the push-up mechanism 50. Then, based on the image acquired by the imaging unit 60, the position of the frame fixing mechanism 14 is adjusted so that the specific chip 21 to be picked up and the push-up mechanism 50 overlap. Then, the collet 76 is placed in a position overlapping the upper surface of the push-up mechanism 50.

[0056] Next, the push-up mechanism 50 is moved upward, and the lower surface of the chip 21 is pushed upward via the tape 19. Furthermore, the pickup mechanism 70 is moved downward, and the suction surface 76a (see FIG. 4) of the collet 76 is brought into contact with the upper surface of the chip 21 pushed up by the push-up mechanism 50. Then, with the suction surface 76a of the collet 76 and the chip 21 in contact, a negative pressure is applied to the suction surface 76a. As a result, the chip 21 is sucked and held by the collet 76. When the pickup mechanism 70 is moved upward in this state, the chip 21 is peeled off from the tape 19 and picked up by the collet 76.

[0057] If the tape 19 has a property such that its adhesive strength is weakened by irradiation with ultraviolet light, a light source for irradiating ultraviolet light may be provided on the upper surface of the push-up mechanism 50. In this case, when the push-up mechanism 50 is brought into contact with the tape 19, ultraviolet light is irradiated only onto the area of ​​the tape 19 located below the chip 21 to be picked up, thereby partially weakening the adhesive strength of the tape 19. This makes it easier to pick up the desired chip 21, and the arrangement of the other chips 21 is maintained by the adhesive strength of the area of ​​the tape 19 that is not irradiated with ultraviolet light.

[0058] Furthermore, the push-up mechanism 50 or the collet 76 may be provided with a load cell for measuring the load applied to the tip 21. In this case, the load applied to the tip 21 when the tip 21 is picked up can be measured by the load cell. Based on the load measured by the load cell, it becomes possible to, for example, check whether the tip 21 was damaged when being picked up, or appropriately change the pick-up conditions (such as the height of the collet 76 when picking up the tip 21).

[0059] The workpiece 11 after the chips 21 have been picked up may be stored again in the cassette 8. In this case, first, the frame fixing mechanism 14 is moved to the rear of the temporary placement mechanism 10, and the fixing of the frame 17 by the frame fixing mechanism 14 is released. Next, the frame 17 is gripped by the second gripping part 22b of the transport mechanism 20, and the frame 17 is transported onto the pair of second support surfaces 12b. Thereafter, the end of the frame 17 is gripped by the first gripping part 22a of the transport mechanism 20, and the workpiece 11 is stored in the cassette 8.

[0060] Meanwhile, the chip 21 picked up by the collet 76 is transported forward by the collet moving mechanism 80. In front of the push-up mechanism 50, a chip observation mechanism (chip observation unit) 100 for observing the chip 21 picked up by the collet 76 is provided.

[0061] The chip observation mechanism 100 includes a bottom surface observation mechanism 102 that observes the bottom surface of the chip 21, and a side surface observation mechanism 112 that observes the side surface of the chip 21. The bottom surface observation mechanism 102 and the side surface observation mechanism 112 each include an imaging unit (camera) for capturing an image of the chip 21.

[0062] 5(A) is a perspective view showing the bottom surface observation mechanism 102. The bottom surface observation mechanism 102 includes a rectangular parallelepiped support base 104 and a columnar support structure 106 arranged upward from the upper surface of one end of the support base 104. An imaging unit (bottom surface imaging unit) 108 for imaging the bottom surface of the chip 21 is provided on the upper surface of the other end of the support base 104.

[0063] Between the base 4 (see FIGS. 2 and 3) and the support base 104, a vibration-isolating member 110 made of a vibration-isolating material such as vibration-isolating rubber is provided, and the imaging unit 108 is placed on the vibration-isolating member 110. The vibration-isolating member 110 suppresses the transmission of vibrations from the base 4 to the imaging unit 108.

[0064] As described above, the first support portion 74a and the second support portion 74b of the arm 74 are configured to be connectable to and separable from each other. The upper surface of the support structure 106 is a flat surface that is roughly parallel to the horizontal plane (XY plane), and forms a holding surface 106a that holds the second support portion 74b separated from the first support portion 74a.

[0065] 5(B) is a perspective view showing the bottom surface observation mechanism 102 holding the second support part 74b of the arm 74. The bottom surface 74c of the second support part 74b separated from the first support part 74a is supported by the holding surface 106a. This fixes the second support part 74b to the bottom surface observation mechanism 102.

[0066] For example, the holding surface 106a is connected to a suction source (not shown) such as an ejector via a flow path (not shown) formed inside the support structure 106, and holds the second support portion 74b by attracting the lower surface 74c of the second support portion 74b. However, there is no limitation on the method for holding the second support portion 74b. For example, the holding surface 106a may be formed of a magnet, and the lower surface 74c of the second support portion 74b, which is made of a magnetic material, may be held by magnetic force.

[0067] With the second support portion 74b held by the holding surface 106a, the imaging unit 108 images the underside of the chip 21 held by the collet 76. This prevents vibrations of the first support portion 74a caused by driving the collet moving mechanism 80, etc., from being transmitted to the chip 21, and improves the accuracy of the imaging of the chip 21 by the imaging unit 108.

[0068] 6(A) is a front view showing the imaging unit 108 that images the underside of the chip 21. The chip 21 held by the collet 76 is positioned so as to overlap with the imaging unit 108, and the underside of the chip 21 is imaged by the imaging unit 108. As a result, an image (underside image) representing the underside of the chip 21 is acquired. This makes it possible to check the condition of the underside of the chip 21 in advance before measuring the strength of the chip 21 with the measuring unit 200, which will be described later.

[0069] The imaging unit 108 is installed at a position that overlaps with the movement path of the collet 76. Therefore, by adjusting the position of the collet 76, the chip 21 can be placed directly above the imaging unit 108 while being held by the collet 76.

[0070] 2 and 3, a side surface observation mechanism 112 is provided in front of the bottom surface observation mechanism 102. The side surface observation mechanism 112 includes a columnar chip support base 114 that supports the chip 21, and an imaging unit (side surface imaging unit) 116 that images the side surface of the chip 21.

[0071] The upper surface of the chip support base 114 is a flat surface roughly parallel to the horizontal plane (XY plane) and constitutes a support surface 114a that supports the chip 21. A rotation drive source (not shown), such as a motor, is connected to the chip support base 114 to rotate the chip support base 114 around a rotation axis roughly parallel to the Z-axis direction. The imaging unit 116 is disposed in a position where it can capture an image of the side surface of the chip 21 placed on the support surface 114a.

[0072] 6(B) is a front view showing the imaging unit 116 that images the side surface of the chip 21. The chip 21 held by the collet 76 is placed on the support surface 114a of the chip support base 114. The side surface of the chip 21 is then imaged by the imaging unit 116. As a result, an image (side surface image) representing the side surface of the chip 21 is acquired. This makes it possible to check the condition of the side surface of the chip 21 in advance before measuring the strength of the chip 21 with the measuring unit 200, which will be described later.

[0073] The chip support base 114 is installed at a position that overlaps with the movement path of the collet 76. Therefore, the chip 21 can be placed on the chip support base 114 by adjusting the position of the collet 76.

[0074] Furthermore, two or more side images can be acquired by imaging the chip 21 multiple times with the imaging unit 116 while rotating the chip support base 114. For example, after imaging one side of the chip 21 supported by the chip support base 114 with the imaging unit 116, the chip support base 114 is rotated by 90° and the other side of the chip 21 is imaged with the imaging unit 116. By repeating this procedure, four side faces of the chip 21 are imaged.

[0075] Furthermore, after the imaging unit 116 captures an image of the chip 21, the orientation of the chip 21 transferred from the chip support base 114 to the measuring unit 200 (see FIGS. 2 and 3) described below can be adjusted by controlling the rotation angle of the chip support base 114. This allows the chip 21 to be placed in the measuring unit 200 in any orientation.

[0076] The bottom surface and side surface of the chip 21 picked up by the collet 76 are observed by the bottom surface observation mechanism 102 and the side surface observation mechanism 112. The imaging unit 116 that images the side surface of the chip 21 may be provided in a position where it can image the side surface of the chip 21 (see FIG. 6(A)) while it is held by the collet 76. In this case, the bottom surface and side surface of the chip 21 can be simultaneously imaged by the imaging units 108 and 116.

[0077] The type of imaging units 108, 116 is appropriately selected depending on the required resolution of the bottom and side images, the material of the chip 21, and the like. For example, the imaging units 108, 116 can be a camera (visible light camera, infrared camera, etc.) equipped with an optical microscope and an imaging element such as a CCD (Charged-Coupled Devices) sensor or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor. The imaging units 108, 116 may also be configured with an interferometer equipped with an interference objective lens, etc. This makes it possible to detect minute irregularities formed on the chip 21.

[0078] 7(A) is a partial cross-sectional front view showing the imaging unit 108. The imaging unit 108 includes a box-shaped housing 120, an imaging element 122 provided in the upper part of the housing 120, and an interference objective lens 124 provided in the lower part of the housing 120. The housing 120 contains a light irradiation unit 126 such as a white LED, and a half mirror 128 arranged between the imaging element 122 and the interference objective lens 124. The light irradiation unit 126 is arranged in a position where it can irradiate light toward the half mirror 128.

[0079] A piezoelectric element 130 whose length changes in response to a voltage supplied from a power supply 132 is provided between the housing 120 and the interference objective lens 124. By controlling the voltage supplied from the power supply 132 to the piezoelectric element 130, the position (height) of the interference objective lens 124 in the Z-axis direction is adjusted.

[0080] 7(B) is a schematic diagram showing the interference objective lens 124. The interference objective lens 124 includes an objective lens 134, a reference mirror 138 provided on a glass plate 136, and a half mirror 140. The reference mirror 138 is disposed at a position symmetrical to the focal position of the objective lens 134 with respect to the half mirror 140.

[0081] The white light emitted from the light irradiation unit 126 is reflected by the half mirror 128 and enters the interference objective lens 124. Then, the light that passes through the half mirror 140 and is reflected by the underside of the chip 21 interferes with the light that is reflected by the half mirror 140 and the reference mirror 138. The light obtained by this interference is detected by the image sensor 122.

[0082] The light obtained by interference produces interference fringes according to the distance between the interference objective lens 124 and the bottom surface of the chip 21. Based on the intensity of these interference fringes, minute irregularities on the bottom surface of the chip 21 are detected.

[0083] Although Fig. 7(B) shows a Mirau-type interference objective lens 124, there is no limitation on the structure of the interference objective lens 124. For example, the imaging unit 108 may be equipped with a Michelson-type or Linnik-type interference objective lens. The configuration of the imaging unit 108 shown in Figs. 7(A) and 7(B) can also be applied to the imaging unit 116.

[0084] 2 and 3, a chip inversion mechanism 150 that turns the chip 21 upside down is provided above the chip support base 114 of the side observation mechanism 112. The chip inversion mechanism 150 is configured to be able to rotate the chip 21 by 180° around a rotation axis that is approximately parallel to the X-axis direction while holding the chip 21 at its tip.

[0085] 8(A) is a perspective view showing the chip inversion mechanism 150. The chip inversion mechanism 150 includes a plate-like base 150a arranged generally parallel to the YZ plane, and a plate-like connection part 150b arranged from the surface of the base 150a along the X-axis direction toward the chip support base 114 and the imaging unit 116.

[0086] A rectangular tip holder 150c that protrudes upward from the upper surface of the connecting portion 150b is provided at the tip of the connecting portion 150b. The tip holder 150c is formed in a rectangular shape corresponding to the shape of the tip 21. The upper surface of the tip holder 150c is a flat surface that is roughly parallel to the horizontal plane (XY plane) and forms a holding surface 150d that holds the tip 21. For example, the holding surface 150d is connected to a suction source (not shown) such as an ejector via a flow channel (not shown) formed inside the tip holder 150c.

[0087] The base portion 150a is configured to be rotatable by 180° around a rotation axis that is approximately parallel to the X-axis direction. Furthermore, the chip holding portion 150c is positioned so as to face (overlap) the support surface 114a of the chip support base 114 when the base portion 150a is rotated and the chip holding portion 150c is positioned below the connection portion 150b (see FIG. 8(B)).

[0088] When flipping the orientation of the chip 21 upside down, first, the base 150a is rotated 180° in a first direction (counterclockwise when viewed from the imaging unit 116 side) to flip the chip inverting mechanism 150 upside down. As a result, the chip holding part 150c faces the chip 21 supported by the chip support base 114 and comes into contact with the upper surface of the chip 21. Then, the suction force (negative pressure) of the suction source is applied to the holding surface 150d of the chip holding part 150c, and the chip 21 is sucked and held by the chip holding part 150c. FIG. 8(B) is a perspective view showing the chip inverting mechanism 150 holding the chip 21.

[0089] When the base portion 150a is rotated 180° in the second direction (clockwise as viewed from the imaging unit 116 side) while the tip 21 is held by the tip holding portion 150c, the tip inversion mechanism 150 is turned upside down. As a result, the lower surface side of the tip 21 (corresponding to the back surface 11b side of the workpiece 11) becomes exposed upward, and the tip 21 is turned upside down. FIG. 8(C) is a perspective view showing the tip inversion mechanism 150 with the tip 21 inverted.

[0090] When the lower surface side of the chip 21 exposed upward is held by a collet 76 (see FIG. 4, etc.), the chip 21 can be transported to the measuring unit 200 (described later) with the lower surface side of the chip 21 facing upward. In this way, the chip inverting mechanism 150 changes the up-down orientation of the chip 21 transported to the measuring unit 200.

[0091] 2 and 3, a measurement unit (measurement mechanism) 200 for measuring the strength of the chips 21 is provided in front of the chip observation mechanism 100 and the chip inversion mechanism 150. The measurement unit 200 measures the flexural strength (bending strength) of the chips 21 obtained by dividing the workpiece 11.

[0092] The chip 21 pushed up by the push-up mechanism 50 is transported from above the push-up mechanism 50 to the measurement unit 200 by the pickup mechanism 70 and the collet moving mechanism 80. The bottom surface observation mechanism 102 and the side surface observation mechanism 112 are disposed in an area overlapping with the movement path of the collet 76 heading from above the push-up mechanism 50 toward the measurement unit 200. Therefore, while the chip 21 is being transported to the measurement unit 200, the chip 21 can be observed by the chip observation mechanism 100.

[0093] 9 is a perspective view showing the measuring unit 200. The measuring unit 200 includes a box-shaped lower container (receiving section) 204 formed in a rectangular parallelepiped shape. The lower container 204 has a rectangular parallelepiped opening 204b that opens upward on the upper surface 204a side of the lower container 204. A support unit 206 is provided inside the opening 204b to support a chip 21 (see FIG. 1(B)) whose strength is to be measured by the measuring unit 200. The chip 21 picked up by the collet 76 (see FIG. 2, etc.) is transported to the measuring unit 200 and placed on the support unit 206.

[0094] 10 is a perspective view showing the support unit 206. The support unit 206 includes a pair of support stages 208 that support the chip 21. The pair of support stages 208 are each formed in a rectangular parallelepiped shape and are arranged spaced apart from each other so that a gap 210 is provided between the pair of support stages 208. Furthermore, the support stage 208 includes a rectangular upper surface 208a, and is arranged so that the longitudinal direction of the upper surface 208a is along the Y-axis direction. The chip 21 whose strength is to be measured is placed on the pair of support stages 208.

[0095] On the upper surface 208a side of each of the pair of support bases 208, a columnar (rod-shaped) support portion 208b is formed, protruding upward from the upper surface 208a. The support portion 208b is made of a metal such as stainless steel, and is disposed adjacent to the gap 210 so that its length direction is along the Y-axis direction. The pair of support portions 208b are disposed spaced apart from each other across the gap 210, and support the lower surface side of the chip 21. Note that FIG. 10 shows a support portion 208b with a curved upper surface.

[0096] Furthermore, plate-shaped contact members 212 made of a material (such as rubber sponge) that is softer than the support portions 208b are provided on the upper surfaces 208a of the pair of support bases 208, respectively. The pair of contact members 212 are formed in a rectangular shape in a plan view, and are provided on both sides of the pair of support portions 208b. In other words, the contact members 212 are each disposed on the opposite side of the gap 210 of the support portions 208b, and the pair of support portions 208b are disposed between the pair of contact members 212.

[0097] The upper surface of the contact member 212 forms a rectangular contact surface 212a that comes into contact with and supports the chip 21. The contact member 212 is provided so that the contact surface 212a is located above the upper ends of the support portions 208b (for example, about 1 mm above the upper ends of the support portions 208b). Therefore, when the chip 21 is placed on the pair of support bases 208, the lower surface of the chip 21 does not come into contact with the support portions 208b, but comes into contact with the contact surface 212a of the contact member 212. The contact between the support portions 208b and the contact member 212 and the chip 21 will be described in detail later (see FIGS. 12 to 14).

[0098] A support table moving mechanism 214 that moves each of the pair of support tables 208 along the X-axis direction is provided on the rear side of the pair of support tables 208 (on the front side of the inspection device 2). The support table moving mechanism 214 includes a rectangular parallelepiped support structure 216. A pair of guide rails 218 are fixed at a predetermined interval along the X-axis direction on the front side of the support structure 216 (on the rear side of the inspection device 2).

[0099] A pair of ball screws 220 are provided between the pair of guide rails 218 and are arranged generally parallel to the guide rails 218. Pulse motors 222 that rotate the ball screws 220 are connected to the ends of the pair of ball screws 220, respectively.

[0100] Furthermore, the support base movement mechanism 214 includes a pair of moving plates 224 fixed to the rear sides of the pair of support bases 208, respectively. The moving plates 224 are each slidably mounted on the pair of guide rails 218. Furthermore, a nut portion (not shown) is provided on the rear side of each of the pair of moving plates 224. One ball screw 220 is threadedly engaged with the nut portion provided on one of the moving plates 224, and the other ball screw 220 is threadedly engaged with the nut portion provided on the other moving plate 224.

[0101] When the ball screw 220 is rotated by the pulse motor 222, the moving plate 224 screwed onto the ball screw 220 moves in the X-axis direction along the guide rail 218. This adjusts the positions of the pair of support bases 208 in the X-axis direction and the width of the gap 210.

[0102] 9, the support unit 206 and the support platform moving mechanism 214 are housed in the opening 204b of the lower container 204. The shapes and sizes of the lower container 204 and the opening 204b are set appropriately depending on the shapes and sizes of the support unit 206 and the support platform moving mechanism 214.

[0103] A pressing unit 226 is provided above the lower container 204. The pressing unit 226 presses the chip 21 supported by the support unit 206, and measures the load acting on the pressing unit 226 when pressing the chip 21.

[0104] 11 is a perspective view showing the pressing unit 226. The pressing unit 226 includes a movable base 228 connected to a moving mechanism 240. A cylindrical first support member 230 is connected to the lower surface of the movable base 228 and is disposed downward from the lower surface of the movable base 228. A load measuring device 232 constituted by a load cell or the like is fixed to the lower end side of the first support member 230.

[0105] A clamping member 236 is connected to the underside of the load measuring instrument 232 via a cylindrical second support member 234. The clamping member 236 is formed in a generally gate-like shape when viewed from the front, and has a pair of clamping surfaces 236a facing each other. An indenter 238 that presses the chip 21 supported by the support unit 206 is fixed between the pair of clamping surfaces 236a.

[0106] The tip (lower end) of the indenter 238 is formed in a tapered shape that narrows downward. That is, both side surfaces of the tip of the indenter 238 are inclined with respect to the vertical direction. The tip (lower end) of the indenter 238 is also formed in a rounded shape (R-shape) (see FIG. 12, etc.). However, the shape of the indenter 238 is not limited to the above.

[0107] The indenter 238 is supported by the clamping member 236 so that its lower end is aligned along the Y-axis direction. That is, the lower end of the indenter 238 and the pair of support portions 208b (see FIG. 10) provided on the support unit 206 are disposed approximately parallel to each other.

[0108] Furthermore, a movement mechanism 240 that moves the pressing unit 226 along the Z-axis direction is provided on the back side of the pressing unit 226 (the front side of the inspection device 2). The movement mechanism 240 includes a rectangular parallelepiped support structure 242. A pair of guide rails 244 are fixed at a predetermined interval along the Z-axis direction on the front side of the support structure 242 (the rear side of the inspection device 2).

[0109] A ball screw 246 is provided between the pair of guide rails 244 and is arranged generally parallel to the guide rails 244. A pulse motor 248 that rotates the ball screw 246 is connected to the end of the ball screw 246.

[0110] The back side of the movable base 228 is slidably mounted on a pair of guide rails 244. A nut portion (not shown) is provided on the back side of the movable base 228, and a ball screw 246 is threadedly engaged with this nut portion. When the ball screw 246 is rotated by the pulse motor 248, the movable base 228 moves in the Z-axis direction along the guide rails 244. This controls the position of the pressing unit 226 in the Z-axis direction. When the pressing unit 226 is moved along the Z-axis direction by the movement mechanism 240, the indenter 238 moves closer to and away from the support unit 206.

[0111] 9, a pair of plate-shaped connecting members 250 are fixed to both side surfaces of movable base 228. Connecting members 250 are provided downward from the side surfaces of movable base 228, and the lower ends of connecting members 250 are located lower than the lower ends of clamping members 236.

[0112] A pair of upper container support parts 250a that protrude toward the indenter 238 are formed at the lower ends of the pair of connecting members 250. A rectangular parallelepiped upper container (cover) 252 that covers the tip of the indenter 238 is fixed between the pair of upper container support parts 250a. The upper container 252 is disposed above the lower container 204, and both side surfaces of the upper container 252 are supported by the pair of upper container support parts 250a.

[0113] The upper container 252 is a box-shaped member made of, for example, a transparent material (glass, plastic, etc.). The upper container 252 has a rectangular parallelepiped opening 252b (see FIG. 12, etc.) that opens downward on the lower surface 252a side of the upper container 252. Furthermore, an indenter insertion hole 252d is formed on the upper surface 252c side of the upper container 252, and the tip of the indenter 238 is inserted into the indenter insertion hole 252d. Therefore, the tip of the indenter 238 is covered by the upper container 252. Note that in FIG. 9, a part of the indenter 238 that is covered by the upper container 252 is shown by a dashed line.

[0114] The upper container 252 is formed to a size that allows it to be inserted into the opening 204b of the lower container 204, and is disposed inside the opening 204b of the lower container 204 in a plan view. Furthermore, the opening 252b of the upper container 252 (see FIG. 12, etc.) is formed to a size that allows it to house the support unit 206. Therefore, when the pressing unit 226 is moved downward by the movement mechanism 240, the upper container 252 is inserted into the opening 204b of the lower container 204, and the upper side of the support unit 206 is covered by the upper container 252.

[0115] A nozzle insertion hole 252f is provided in a side wall 252e of the upper container 252. A gas supply unit 254 that blows gas such as air onto the tip of the indenter 238 is connected to the nozzle insertion hole 252f.

[0116] The gas supply unit 254 includes a nozzle 256 that sprays gas toward the indenter 238. One end of the nozzle 256 is inserted into the upper container 252 through a nozzle insertion hole 252f, and the other end of the nozzle 256 is connected to a gas supply source 260 through a valve 258. A tip 256a (see FIG. 12, etc.) on one end of the nozzle 256 opens toward the side surface of the tip of the indenter 238.

[0117] Gas such as air supplied from gas supply source 260 to nozzle 256 via valve 258 is sprayed onto the side surface of the tip of indenter 238. This removes foreign matter adhering to the tip of indenter 238, support portion 208b, contact surface 212a (see FIG. 10), etc. Details of the operation of gas supply unit 254 will be described later.

[0118] An outlet 204d is formed in the bottom of the lower container 204, penetrating from the bottom of the opening 204b of the lower container 204 to the lower surface (bottom surface) 204c of the lower container 204. A discharge unit 262 is connected to the outlet 204d, which discharges foreign matter such as broken pieces of the chips 21 present inside the lower container 204.

[0119] The discharge unit 262 includes a discharge path 264 that forms a path for discharging foreign matter. For example, the discharge path 264 is formed of a pipe, a tube, or the like. One end of the discharge path 264 is connected to the discharge port 204d. The other end of the discharge path 264 is connected via a valve 266 to a suction source 268 such as an ejector.

[0120] Furthermore, a collection unit 270 that collects foreign matter is provided in the discharge path 264. The collection unit 270 is configured with a filter or the like, and captures foreign matter passing through the discharge path 264. When the valve 266 is opened, pieces of chips 21 scattered inside the opening 204b of the lower container 204 are sucked through the discharge port 204d and collected by the collection unit 270. The operation of the discharge unit 262 will be described in detail later.

[0121] Furthermore, an imaging unit 272 and a light source 274 that irradiates light toward the imaging unit 272 are provided at the front and rear of the lower container 204, facing each other across the upper part of the support unit 206. The positions of the imaging unit 272 and the light source 274 are adjusted so that the imaging unit 272 can capture images of the tip 21 and the tip of the indenter 238 supported by the support unit 206, etc.

[0122] By capturing an image of the tip of the indenter 238 with the imaging unit 272 while irradiating it with light from the light source 274, it is possible to observe how the chip 21 is being pressed by the indenter 238 and the state of the tip of the indenter 238 (presence or absence of foreign matter, presence or absence of chipping, etc.). However, if the imaging by the imaging unit 272 is performed in a sufficiently bright environment, the light source 274 may be omitted.

[0123] By using the above-described measuring unit 200, it is possible to perform a three-point bending test on the chip 21. The three-point bending test measures the flexural strength (bending strength) of the chip 21. An example of the operation of the measuring unit 200 when measuring the strength of the chip 21 will be described below.

[0124] Fig. 12 is a cross-sectional view showing the measurement unit 200 in a state in which the tip 21 is supported by the support unit 206. As shown in Fig. 12, the indenter 238 is disposed above the pair of supports 208b so as to overlap with the region (gap 210) between the pair of supports 208b. The indenter 238 is also disposed so that its tip (lower end) is aligned along the length direction (Y-axis direction) of the support 208b.

[0125] When measuring the strength of the chip 21, first, the positions of the pair of support bases 208 in the X-axis direction are adjusted by the support base moving mechanism 214 (see FIG. 10). The positions of the pair of support bases 208 are adjusted so that a gap 210 of an appropriate width is formed according to the dimensions of the chip 21, etc. Then, the chip 21 is placed on the pair of support bases 208. Specifically, with the chip 21 held by the collet 76 (see FIG. 2, etc.) positioned on the pair of support bases 208, the suction of the chip 21 by the collet 76 is released. At this time, the chip 21 is placed so that both end portions are supported by the pair of support bases 208 and the center portion overlaps the gap 210.

[0126] When placing chip 21 on the pair of supports 208, if the underside of chip 21 comes into contact with support portion 208b, the underside of chip 21 may be damaged by the impact during placement. In this case, the strength of chip 21 changes, which may make it difficult to measure the strength of multiple chips 21 under the same conditions.

[0127] However, a flexible contact member 212 is provided on the upper surface 208a side of the support base 208. Furthermore, the contact surface 212a of the contact member 212 is located higher than the upper end of the support portion 208b. Therefore, when the chip 21 is placed on the pair of support bases 208, the chip 21 comes into contact with the contact surface 212a of the contact member 212 without coming into contact with the support portion 208b, and is supported by the contact surface 212a. This makes it possible to prevent the lower surface side of the chip 21 from coming into contact with the support portion 208b and being damaged when the chip 21 is placed.

[0128] Next, the pressing unit 226 is lowered by the moving mechanism 240 (see FIG. 11). As the pressing unit 226 is lowered, the tip of the indenter 238 comes into contact with the upper surface side of the chip 21, and the chip 21 is pressed by the indenter 238. In addition, the load (force in the Z-axis direction) applied to the indenter 238 by the pressing of the chip 21 is measured by the load measuring device 232 (see FIG. 11).

[0129] When pressing unit 226 is further lowered, chip 21 is further pressed by indenter 238, causing chip 21 to bend and contact member 212 supporting chip 21 to deform. As a result, the lower surface side of chip 21 comes into contact with support portion 208b of support base 208. Depending on the flexibility of contact member 212, there may be cases where only contact member 212 deforms and chip 21 does not bend.

[0130] 13 is a cross-sectional view showing measurement unit 200 in a state where tip 21 is in contact with support portions 208b of support base 208. When tip 21 comes into contact with the pair of support portions 208b, tip 21 is supported by the pair of support portions 208b, and the load on indenter 238 pressing against tip 21 increases. Furthermore, when pressing unit 226 is further lowered, tip 21 is further pressed by indenter 238 while being supported by the pair of support portions 208b. When the pressing force applied to tip 21 by indenter 238 exceeds a predetermined value, tip 21 is destroyed.

[0131] 14 is a cross-sectional view showing the measurement unit 200 in a state where the tip 21 has been broken. When the tip 21 is broken, the load measured by the load measuring instrument 232 decreases from its maximum value to zero. Therefore, the timing at which the tip 21 has been broken can be detected from the change in the value of the load measured by the load measuring instrument 232. Furthermore, the maximum value of the load measured by the load measuring instrument 232 corresponds to the strength of the tip 21.

[0132] Specifically, the value of the bending stress of the chip 21 is calculated based on the maximum value of the load applied to the indenter 238, the distance between the upper ends of the pair of support portions 208b, and the dimensions of the chip 21. If the maximum value of the load applied to the indenter 238 pressing the chip 21 is W [N], the distance between the upper ends of the pair of support portions 208b is L [mm], the width of the chip 21 (the length of the chip 21 in the direction perpendicular to the line connecting the pair of support portions 208b (Y-axis direction)) is b [mm], and the thickness of the chip 21 is h [mm], then the bending stress value σ of the chip 21 is σ=3WL / 2bh 2 It is expressed as:

[0133] If the tip 21 is broken, fragments 23 of the tip 21 will scatter. However, when the tip 21 is pressed by the indenter 238, the upper container 252 is positioned so as to cover the upper side of the tip 21 and the support unit 206. This makes it possible to prevent fragments 23 of the tip 21 from scattering outside the measurement unit 200.

[0134] When the indenter 238 presses the chip 21, foreign matter (such as fragments 23 of the chip 21) may adhere to the indenter 238. This foreign matter may affect the accuracy of the test, so it is preferable to remove it. Therefore, after testing the chip 21, it is preferable to blow gas onto the indenter 238 using the gas supply unit 254 to remove the foreign matter adhering to the indenter 238.

[0135] Specifically, valve 258 of gas supply unit 254 is opened, and gas such as air supplied from gas supply source 260 is sprayed from tip 256a of nozzle 256 toward the side surface of the tip of indenter 238. This causes foreign matter adhering to the tip of indenter 238 to be blown away and removed. There is no limit to the timing for removing foreign matter using gas supply unit 254. For example, foreign matter removal is performed as needed after the test of one chip 21 is completed and before the test of the next chip 21 is started.

[0136] Furthermore, the gas injected toward the tip of the indenter 238 flows inside the upper container 252 and is also sprayed onto the pair of support stands 208. As a result, foreign matter (such as chip fragments 23) adhering to the support part 208b and the contact surface 212a of the contact member 212 is blown away and removed by the gas. This makes it possible to prevent foreign matter from coming into contact with the underside of the chip 21 and damaging the chip 21 when the next test is performed.

[0137] If the tip 256a of the nozzle 256 is positioned toward the upper surface 208a of the support stand 208, the air ejected from the nozzle 256 will be strongly blown toward the upper surface 208a of the support stand 208. In this case, foreign matter adhering to the support portion 208b or the contact member 212 may be blown away by the air, float up inside the upper container 252, and then adhere again to the support portion 208b or the contact member 212. Therefore, it is difficult to properly remove the foreign matter from the upper surface 208a side of the support stand 208.

[0138] Therefore, in the measurement unit 200, the nozzle 256 is positioned so that the tip 256a of the nozzle 256 opens toward the side surface of the tip of the indenter 238. This appropriately weakens the force of the air blown onto the upper surface 208a of the support base 208. As a result, foreign matter is appropriately removed from the upper surface 208a side of the support base 208.

[0139] When the measurement of the strength of the chips 21 and the removal of foreign matter by the gas supply unit 254 are repeated, fragments 23 of the chips 21 accumulate inside the lower container 204. Therefore, the fragments 23 accumulated inside the lower container 204 are collected using the discharge unit 262 (see FIG. 9).

[0140] Specifically, the valve 266 of the discharge unit 262 is opened, and the debris 23 accumulated inside the opening 204b is sucked through the discharge port 204d provided in the lower container 204. The sucked debris 23 passes through the discharge path 264 and is collected by the collection unit 270. This allows the debris 23 to be quickly removed without having to manually clean the inside of the opening 204b of the lower container 204.

[0141] In the measurement unit 200, the upper container 252 is formed smaller than the opening 204b of the lower container 204, and an indenter insertion hole 252d into which the indenter 238 is inserted is formed in the upper container 252. Therefore, even if the upper container 252 is lowered toward the lower container 204, the opening 204b of the lower container 204 is not sealed by the upper container 252. As a result, when the fragments 23 of the tip 21 are aspirated through the outlet 204d, outside air is easily taken into the opening 204b, and the fragments 23 of the tip 21 can be aspirated smoothly.

[0142] 2 and 3, a display unit (display section, display device) 280 that displays information related to the inspection device 2 is provided on the front side of the measurement unit 200. The display unit 280 can be configured with various displays, and displays various information related to chip inspection (inspection conditions, inspection status, inspection results, etc.).

[0143] For example, a touch panel display is used as the display unit 280. In this case, the display unit 280 also functions as an input unit (input section, input device) for inputting information to the inspection device 2, and the operator can input information to the inspection device 2 by touching the display unit 280. In other words, the display unit 280 functions as a user interface.

[0144] The inspection device 2 also includes a control unit (controller, control device) 290 that controls the inspection device 2. The control unit 290 is connected to each of the components that make up the inspection device 2 (the cassette mounting table 6, the frame fixing mechanism 14, the transport mechanism 20, the moving mechanism 30, the push-up mechanism 50, the imaging unit 60, the pickup mechanism 70, the collet moving mechanism 80, the chip observation mechanism 100, the chip inverting mechanism 150, the measurement unit 200, the display unit 280, etc.).

[0145] For example, the control unit 290 is configured by a computer, and includes a processor such as a CPU (Central Processing Unit) that performs calculations necessary for the operation of the inspection device 2, and memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory) that store various information (data, programs, etc.) used for the operation of the inspection device 2. The control unit 290 outputs control signals to each component of the inspection device 2, thereby controlling the operation of each component and operating the inspection device 2.

[0146] <Chip inspection example 1> Next, a specific example of a chip inspection method for inspecting chips using the inspection device 2 shown in Figures 2 and 3 will be described. Figure 15 is a flowchart showing a first chip inspection method. The first chip inspection method includes a dividing step S1, an imaging step S2, and an inspection step S3. By sequentially performing the dividing step S1, the imaging step S2, and the inspection step S3, the workpiece 11 is divided into a plurality of chips 21 (see Figure 1(B)), and the state of the chips 21 is inspected.

[0147] First, the workpiece 11 is divided into a plurality of chips 21 by processing the workpiece 11 under predetermined dividing processing conditions (dividing step S1). In the dividing step S1, the workpiece 11 is divided into a plurality of chips 21 by processing the workpiece 11 using a processing device such as a cutting device or a laser processing device. Below, as an example, a case will be described in which the dividing step S1 includes a step of forming a modified layer inside the workpiece 11 (modified layer forming step) and a step of applying an external force to the workpiece 11 (external force applying step).

[0148] Fig. 16 is a partial cross-sectional front view showing the laser processing apparatus 300. In the modified layer forming step, the laser processing apparatus 300 performs laser processing on the workpiece 11 to form a modified layer inside the workpiece 11. In Fig. 16, the X-axis direction (processing feed direction, first horizontal direction) and the Y-axis direction (indexing feed direction, second horizontal direction) are perpendicular to each other. Furthermore, the Z-axis direction (vertical direction, up-down direction, height direction) is perpendicular to the X-axis direction and the Y-axis direction.

[0149] The laser processing apparatus 300 includes a chuck table (holding table) 302 that holds the workpiece 11. The upper surface of the chuck table 302 is a circular flat surface that is roughly parallel to the horizontal plane (XY plane), and constitutes a holding surface 302a that holds the workpiece 11. The holding surface 302a is connected to a suction source (not shown) such as an ejector via a flow path (not shown), a valve (not shown), and the like that are formed inside the chuck table 302.

[0150] A ball screw type moving mechanism (not shown) that moves the chuck table 302 along the X-axis and Y-axis directions is connected to the chuck table 302. A rotation drive source (not shown) such as a motor that rotates the chuck table 302 around a rotation axis that is approximately perpendicular to the holding surface 302a is also connected to the chuck table 302. Furthermore, a plurality of clamps 304 that grip and fix the frame 17 that supports the workpiece 11 are provided around the periphery of the chuck table 302.

[0151] The laser processing apparatus 300 also includes a laser irradiation unit 306 that irradiates a laser beam. The laser irradiation unit 306 includes a laser oscillator (not shown) such as a YAG laser, a YVO4 laser, or a YLF laser, and a laser processing head 308 disposed above the chuck table 302.

[0152] The laser processing head 308 has a built-in optical system that guides a pulsed laser beam emitted from a laser oscillator to the workpiece 11, and the optical system includes optical elements such as a condenser lens that condenses the laser beam. The workpiece 11 is processed by the laser beam 310 irradiated from the laser processing head 308.

[0153] Furthermore, the laser processing apparatus 300 includes a control unit (control section, control device) 312 that controls the laser processing apparatus 300. The control unit 312 is connected to each of the components that make up the laser processing apparatus 300 (such as the laser irradiation unit 306).

[0154] For example, the control unit 312 is configured by a computer, and includes a processor such as a CPU that performs calculations necessary for the operation of the laser processing apparatus 300, and memories such as a ROM and a RAM that store various information (data, programs, etc.) used for the operation of the laser processing apparatus 300. The control unit 312 outputs control signals to each component of the laser processing apparatus 300, thereby controlling the operation of each component and operating the laser processing apparatus 300.

[0155] When processing the workpiece 11 with the laser processing device 300, the workpiece 11 is first held by the chuck table 302. For example, the workpiece 11 is placed on the chuck table 302 so that the front surface 11a faces upward and the back surface 11b (the tape 19 side) faces the holding surface 302a. The frame 17 is also fixed by a plurality of clamps 304. In this state, when the suction force (negative pressure) of the suction source is applied to the holding surface 302a, the workpiece 11 is suction-held by the chuck table 302 via the tape 19.

[0156] Next, the chuck table 302 is rotated to align the length direction of a predetermined street 13 (see FIG. 1(A)) with the X-axis direction. The position of the chuck table 302 in the Y-axis direction is also adjusted so that the area irradiated with the laser beam 310 is positioned on an extension of the predetermined street 13. Furthermore, the position of the laser processing head 308 and the arrangement of the optical system are adjusted so that the focal point of the laser beam 310 is positioned at the same height (position in the Z-axis direction) as the interior of the workpiece 11 (between the front surface 11a and the back surface 11b).

[0157] Then, while irradiating the laser beam 310 from the laser processing head 308, the chuck table 302 is moved along the X-axis direction. This causes the chuck table 302 and the laser beam 310 to move relatively along the processing feed direction at a predetermined speed (processing feed speed). As a result, the laser beam 310 is irradiated along the street 13 from the front surface 11a side of the workpiece 11.

[0158] The laser processing device 300 processes the workpiece 11 under predetermined divided processing conditions registered in advance in the control unit 312. Specifically, the irradiation conditions of the laser beam 310 are set so that the area of ​​the workpiece 11 irradiated with the laser beam 310 is modified and altered by multiphoton absorption.

[0159] The wavelength of the laser beam 310 is set so that at least a portion of the laser beam 310 is transmitted through the workpiece 11. In other words, the laser beam 310 is a laser beam that is transparent to the workpiece 11. Other irradiation conditions of the laser beam 310 are also set so that the workpiece 11 is appropriately modified. For example, when the workpiece 11 is a single crystal silicon wafer, the irradiation conditions of the laser beam 310 can be set as follows: Wavelength: 1064nm Average power: 1W Repetition frequency: 100kHz Processing feed rate: 800mm / s

[0160] When the workpiece 11 is processed under the above-described dividing processing conditions, the inside of the workpiece 11 is modified and altered by multiphoton absorption, and modified layers (altered layers) 25 are formed along the streets 13 inside the workpiece 11. Thereafter, by repeating the same procedure, the laser beam 310 is irradiated along the other streets 13. As a result, multiple modified layers 25 are formed in a lattice pattern along each street 13 inside the workpiece 11.

[0161] The region of the workpiece 11 where the modified layer 25 is formed becomes more fragile than other regions of the workpiece 11. Therefore, when an external force is applied to the workpiece 11, the workpiece 11 is split along the streets 13 starting from the modified layer 25. In other words, the modified layer 25 functions as a splitting starting point (a trigger for splitting).

[0162] The modified layer 25 may be formed in multiple stages in the thickness direction of the workpiece 11. For example, if the workpiece 11 is a single crystal silicon wafer or the like having a thickness of 200 μm or more, forming two or more modified layers 25 makes it easier to properly divide the workpiece 11. When forming multiple modified layers 25, the laser beam 310 is irradiated multiple times along each street 13 while changing the height position of the focal point of the laser beam 310.

[0163] Next, an external force is applied to the workpiece 11, dividing the workpiece 11 along the streets 13 starting from the modified layer 25 (external force application step). For example, in the external force application step, the tape 19 attached to the workpiece 11 is pulled and expanded to apply an external force to the workpiece 11. The expansion of the tape 19 may be performed using a dedicated expansion device or may be performed manually by an operator.

[0164] 17(A) is a partial cross-sectional front view showing the expansion device 400. The expansion device 400 includes a drum 402 formed in a hollow cylindrical shape. At the upper end of the drum 402, a plurality of rollers 404 are arranged at approximately equal intervals along the circumferential direction of the drum 402. In addition, a plurality of columnar support members 406 are arranged on the outside of the drum 402. At the lower end of each of the support members 406, an air cylinder (not shown) is connected to move (raise and lower) the support member 406 in the vertical direction.

[0165] An annular table 408 is fixed to the upper ends of the multiple support members 406. A circular opening 408a is provided in the center of the table 408, penetrating the table 408 in the thickness direction. The diameter of the opening 408a is larger than the diameter of the drum 402, allowing the upper end of the drum 402 to be inserted into the opening 408a. In addition, multiple clamps 410 are arranged on the outer periphery of the table 408, which grip and secure the frame 17 supporting the workpiece 11.

[0166] When dividing the workpiece 11, first, the support member 406 is raised and lowered by an air cylinder (not shown) until the top surface of the table 408 is positioned at approximately the same height as the top ends of the rollers 404. Then, the frame 17 is placed on the table 408 and fixed with a plurality of clamps 410. At this time, the workpiece 11 is positioned so as to overlap the inside of the drum 402.

[0167] Next, the support member 406 is lowered by an air cylinder (not shown), and the table 408 and clamp 410 are pulled down. This pushes down the frame 17, and the tape 19 is pulled while being supported by the rollers 404. As a result, the tape 19 is stretched radially and expanded.

[0168] 17(B) is a partial cross-sectional front view showing an expansion device 400 that expands the tape 19. When the tape 19 is expanded, an external force directed radially outward is applied to the workpiece 11 fixed to the tape 19. As a result, the modified layer 25 functions as a splitting starting point, and the workpiece 11 is broken along the streets 13. This causes the workpiece 11 to be split into a plurality of chips 21, each of which includes a device 15 (see FIG. 1(B)).

[0169] The chip 21 includes a front surface (first surface) 21a and a back surface (second surface) 21b that are generally parallel to each other, and four side surfaces 21c connected to the front surface 21a and the back surface 21b. The front surface 21a corresponds to a part of the front surface 11a of the workpiece 11, and the back surface 21b corresponds to a part of the back surface 11b of the workpiece 11. The side surfaces 21c correspond to surfaces (divided surfaces, processed surfaces) newly formed by dividing the workpiece 11.

[0170] As described above, in the dividing step S1, the workpiece 11 is divided into a plurality of chips 21 by performing the modified layer forming step and the external force applying step. However, there are no limitations on the method for dividing the workpiece 11. For example, in the dividing step S1, the workpiece 11 may be subjected to laser ablation processing. In this case, a laser beam that is absorbable by the workpiece 11 is irradiated along the streets 13. This applies ablation processing to the workpiece 11, and laser-processed grooves extending from the front surface 11a to the back surface 11b of the workpiece 11 are formed along the streets 13. When the laser-processed grooves are formed along all of the streets 13, the workpiece 11 is divided into a plurality of chips 21.

[0171] Next, an image (side image) representing the side of the chip 21 is obtained by imaging the side of the chip 21 (imaging step S2). For example, in the imaging step S2, the side image of the chip 21 is obtained by the inspection device 2 (see FIGS. 2 and 3).

[0172] The workpiece 11 divided into a plurality of chips 21 in the dividing step S1 is stored in a cassette 8 (see FIGS. 2 and 3) and transported to the inspection device 2. Then, the inspection device 2 is operated, and the strength of the chips 21 is measured by the measurement unit 200.

[0173] As described above, while the chip 21 is being transported to the measurement unit 200 by the pickup mechanism 70 and the collet moving mechanism 80 (see FIG. 2), the chip 21 is observed by the chip observing mechanism 100. At this time, the side surface of the chip 21 is imaged by the imaging unit 116 provided in the side surface observing mechanism 112. As a result, an image representing the side surface of the chip 21 (side surface image) is acquired.

[0174] 18 is an image diagram showing a side image 500 of the chip 21. When the workpiece 11 is divided into a plurality of chips 21, the modified layer 25 that functioned as the division starting point remains as a processing mark on the side surface 21c of the chip 21. Therefore, when the side surface 21c of the chip 21 is imaged, a side image 500 including an image of the processing mark (modified layer 25) is acquired.

[0175] Next, the state of the chip 21 is inspected by comparing the evaluation value extracted from the side image 500 with a threshold value (inspection step S3). In inspection step S3, a predetermined value corresponding to the intensity of the chip 21 is extracted as an evaluation value from the side image 500. Then, by determining whether the evaluation value is within a predetermined allowable range, it is inspected whether the state of the chip 21 is normal or abnormal.

[0176] For example, a value corresponding to the gradation of a region 500a representing the modified layer 25 in the side image 500 is extracted as the evaluation value. The region where the modified layer 25 of the chip 21 remains has been modified by irradiation with the laser beam. Therefore, the region 500a in the side image 500 is expressed in a gradation different from that of the other regions of the side image 500. For example, as shown in FIG. 18 , the region 500a in the side image 500 is expressed in a darker color than the other regions.

[0177] Furthermore, the gradation of the region 500a of the side image 500 varies depending on the degree of modification of the chip 21. For example, the higher the average output of the laser beam 310 (see FIG. 16), the greater the degree of modification, and the region 500a of the side image 500 is displayed in a darker color. Also, the greater the degree of modification of the chip 21, the lower the intensity of the chip 21 tends to be. Therefore, the intensity of the chip 21 can be evaluated by extracting the gradation of the region 500a from the side image 500 and comparing the gradation of the region 500a with a predetermined threshold value.

[0178] Specifically, a threshold value that defines an allowable range of values ​​(gradation values) indicating the hue, saturation, brightness, etc. of the region 500a is set in advance before inspecting the chip 21. For example, an upper limit value of the gradation value is set as the threshold value. Then, image processing is performed on the side image 500 acquired by imaging the chip 21, and the gradation value of the region 500a is calculated. The range of the region 500a may be manually specified by an operator who visually checks the side image 500, or may be automatically identified by performing image processing on the side image 500.

[0179] Thereafter, the gradation value of the region 500a is compared with a threshold value to determine whether the gradation value of the region 500a is within an allowable range. For example, the average gradation value of each pixel included in the region 500a is compared with the threshold value. If the gradation value of the region 500a is equal to or less than the threshold value (upper limit), the intensity of the chip 21 meets the standard, and the chip 21 is determined to be normal. On the other hand, if the gradation value of the region 500a exceeds the threshold value (upper limit), the intensity of the chip 21 does not meet the standard, and the chip 21 is determined to be abnormal.

[0180] Furthermore, a value corresponding to the position of the modified layer 25 shown in the side image 500 may be extracted as the evaluation value. As shown in FIG. 18, the side image 500 shows the back surface 21b of the chip 21 and the processing marks (modified layer 25) remaining on the chip 21. The closer the modified layer 25 is to the back surface 21b of the chip 21, the more likely the chip 21 is to be damaged when an impact is applied to the chip 21, and the lower the strength of the chip 21. Therefore, for example, the distance S from the modified layer 25 to the back surface 21b of the chip 21 can be used as the evaluation value.

[0181] When the distance S is used as the evaluation value, a threshold value defining an allowable range of the distance S is set in advance before inspecting the chip 21. For example, a lower limit value of the distance S is set as the threshold value. Then, image processing is performed on the side image 500 acquired by imaging the chip 21, and the distance S is calculated. Note that the distance S may be calculated by an operator visually viewing the side image 500 and specifying the position of the modified layer 25 and the position of the back surface 21b, or may be calculated automatically by performing image processing on the side image 500.

[0182] Thereafter, by comparing the distance S with a threshold value, it is confirmed whether the value of the distance S is within an allowable range. Specifically, if the distance S is equal to or greater than the threshold value (lower limit value), the strength of the tip 21 meets the standard, and the tip 21 is determined to be normal. On the other hand, if the distance S is below the threshold value (lower limit value), the strength of the tip 21 does not meet the standard, and the tip 21 is determined to be abnormal.

[0183] However, the evaluation value extracted from the side image 500 is not limited to the gradation value of the region 500a or the distance S. For example, the distance from the modified layer 25 to the surface 21a of the chip 21, the thickness of the modified layer 25, etc. can also be used as the evaluation value.

[0184] If the chip 21 is determined to be abnormal, the cause of the abnormality is investigated, and the dividing and processing conditions for the workpiece 11 in the dividing step S1 (such as the laser beam irradiation conditions and the tape 19 expansion conditions) are changed as necessary. For example, if the gradation value of the region 500a exceeds a threshold (upper limit), the average output of the laser beam 310 (see FIG. 16) is lowered to reduce the degree of modification of the workpiece 11. If the distance S is below a threshold (lower limit), the height position of the focal point of the laser beam 310 (see FIG. 16) is adjusted. This maintains the intensity of the chips 21 formed thereafter at a constant level or higher.

[0185] Furthermore, when reviewing the dividing processing conditions of the workpiece 11, the operator checks the side image 500. This allows the operator to intuitively grasp the modified state of the tip 21, making it easier to determine the cause of the decrease in strength of the tip 21.

[0186] As described above, by inspecting the state of the chip 21 based on the evaluation value extracted from the side image 500, the state of the chip 21 (such as the degree of modification and the position of the modified layer 25) can be grasped in more detail, which cannot be fully evaluated by measuring only the bending strength using the measurement unit 200 (see FIGS. 2 and 3). This enables appropriate quality evaluation of the chip 21 obtained by dividing the workpiece 11.

[0187] <Chip inspection example 2> Next, a more detailed example of a chip inspection method using the inspection device 2 (see FIGS. 2 and 3), the laser processing device 300 (see FIG. 16), and the extension device 400 (see FIGS. 17(A) and 17(B)) will be described. FIG. 19 is a flowchart showing the second chip inspection method. In the second chip inspection method, an evaluation condition setting step S10 for setting evaluation conditions for the chip and an evaluation step S20 for evaluating the chip are performed.

[0188] 20(A) is a perspective view showing a workpiece (first workpiece) 31 used in the evaluation condition setting step S10, and FIG. 20(B) is a perspective view showing a workpiece (second workpiece) 41 used in the evaluation step S20. In the evaluation condition setting step S10, evaluation conditions for the chip are set using a chip (first chip) obtained by dividing the workpiece 31. In addition, in the evaluation step S20, a chip (second chip) obtained by dividing the workpiece 41 is evaluated.

[0189] The workpiece 31 has a front surface (first surface) 31a and a back surface (second surface) 31b that are generally parallel to each other, and is partitioned into a plurality of rectangular regions by a plurality of streets (planned division lines) 33 arranged in a grid pattern. Furthermore, a device 35 is formed in each of the plurality of regions partitioned by the streets 33. The workpiece 31 corresponds to a wafer used to set evaluation conditions for chips.

[0190] The workpiece 41 has a front surface (first surface) 41a and a back surface (second surface) 41b that are generally parallel to each other, and is partitioned into a plurality of rectangular regions by a plurality of streets (planned division lines) 43 arranged in a grid pattern. Furthermore, a device 45 is formed in each of the plurality of regions partitioned by the streets 43. The workpiece 41 corresponds to a wafer used in the manufacture of product chips.

[0191] The material, shape, structure, size, etc. of the workpieces 31 and 41 can be set in the same way as the workpiece 11 (see FIG. 1(A)). The type, number, shape, structure, size, arrangement, etc. of the devices 35 and 45 can be set in the same way as the device 15 (see FIG. 1(A)). The workpieces 31 and 41 are each supported by the frame 17 via the tape 19.

[0192] In this chip inspection method, evaluation conditions are selected using first chips obtained by dividing workpiece 31, and then second chips obtained by dividing workpiece 41 are evaluated based on the evaluation conditions. Therefore, it is preferable that the material, shape, structure, size, etc. of workpiece 31 be the same as those of workpiece 41. It is also preferable that the type, number, shape, structure, size, arrangement, etc. of devices 35 be the same as those of devices 45. However, workpiece 31 and workpiece 41, and the first chips and second chips may be slightly different within a range that does not result in a large difference in strength between the first chips and the second chips.

[0193] Fig. 21 is a block diagram showing the inspection device 2 and the laser processing device 300. In addition to blocks showing the functional configurations of the control unit 290 of the inspection device 2 and the control unit 312 of the laser processing device 300, Fig. 21 also shows blocks showing the imaging unit 116, measurement unit 200, and display unit 280 of the inspection device 2, and a block showing the laser irradiation unit 306 of the laser processing device 300.

[0194] The control unit 290 of the inspection device 2 includes a setting section 292 that executes processing required to set processing conditions for the workpiece and evaluation conditions for the chip, an inspection section 294 that executes processing required to inspect the chip, and a storage section 296 that stores information (data, programs, etc.) used for processing in the setting section 292 and the inspection section 294. The control unit 290 also includes a transmitting / receiving section 298 that transmits information to the outside of the inspection device 2 and receives information input from the outside of the inspection device 2.

[0195] The control unit 312 of the laser processing apparatus 300 includes a processing unit 314 that executes processing required for processing the workpiece, and a storage unit 316 that stores information (data, programs, etc.) used for the processing in the processing unit 314. The control unit 312 also includes a transmitting / receiving unit 318 that transmits information to the outside of the laser processing apparatus 300 and receives information input from the outside of the laser processing apparatus 300.

[0196] The transmitting / receiving unit 298 of the inspection device 2 and the transmitting / receiving unit 318 of the laser processing device 300 are connected by wire or wirelessly via a network. Therefore, information can be transmitted and received between the inspection device 2 and the laser processing device 300. For example, information stored in the memory unit 296 of the inspection device 2 can be transmitted from the transmitting / receiving unit 298 to the laser processing device 300, and information stored in the memory unit 316 of the laser processing device 300 can be transmitted from the transmitting / receiving unit 318 to the inspection device 2.

[0197] Next, a specific example of chip inspection will be described with reference to Figures 19 to 21. The inspection device 2 and the laser processing device 300 cooperate to carry out an evaluation condition setting step S10 and an evaluation step S20.

[0198] First, a plurality of workpieces 31 (first workpieces, see FIG. 20(A)) are processed under a plurality of processing conditions, thereby dividing each of the workpieces 31 into a plurality of first chips (first dividing step S11). In the first dividing step S11, a plurality of workpieces 31 are prepared, and each of the workpieces 31 is processed by the laser processing device 300.

[0199] Specifically, first, a processing condition setting unit 314a included in the processing unit 314 of the control unit 312 sets a plurality of processing conditions (such as laser beam irradiation conditions) used in laser processing of the workpiece 31. For example, an operator specifies a plurality of processing conditions, and the processing condition setting unit 314a writes the specified plurality of processing conditions into a processing condition storage unit 316a included in the storage unit 316.

[0200] Next, the drive control unit 314b included in the processing unit 314 reads out the first processing conditions stored in the processing condition storage unit 316a, and outputs control signals to the components (laser irradiation unit 306, etc.) of the laser processing device 300 so that the first workpiece 31 is processed under the first processing conditions. As a result, the first workpiece 31 is processed under the first processing conditions, and a modified layer is formed inside the first workpiece 31 along the streets 33 (see FIG. 16).

[0201] Next, the drive control unit 314b reads out the second processing conditions stored in the processing condition storage unit 316a, and outputs control signals to each component of the laser processing device 300 so that the second workpiece 31 is processed under the second processing conditions. As a result, the second workpiece 31 is processed under the second processing conditions, and a modified layer is formed inside the second workpiece 31 along the streets 33 (see FIG. 16).

[0202] By repeating the above process, the plurality of workpieces 31 are processed under different processing conditions, and modified layers are formed inside the plurality of workpieces 31. Thereafter, the plurality of workpieces 31 are transported to an expansion device 400 (see FIGS. 17(A) and 17(B)), and an external force is applied to the workpieces 31 by the expansion device 400. As a result, the plurality of workpieces 31 are each divided into a plurality of first chips.

[0203] The details of processing the workpiece 31 by the laser processing device 300 and the expansion device 400 are the same as those of processing the workpiece 11 in the above-mentioned division step S1 (see FIG. 15). Then, the workpiece 31 divided into a plurality of first chips is housed in a cassette 8 (see FIGS. 2 and 3) and transported to the inspection device 2. In addition, a plurality of processing conditions used in processing the workpiece 31 are transmitted from the transmission / reception unit 318 to the inspection device 2.

[0204] Next, the side surface of the first chip is imaged to obtain a first side image representing the side surface of the first chip (first imaging step S12). In the first imaging step S12, the workpiece 31 is carried out from the cassette 8 (see FIGS. 2 and 3) and placed above the push-up mechanism 50. The pickup mechanism 70 picks up the first chip from the workpiece 31 and transports the first chip to the side surface observation mechanism 112. The imaging unit 116 then images the side surface of the first chip, and a first side image representing the side surface of the first chip is obtained (see FIG. 18). Details of the imaging of the first chip by the imaging unit 116 are the same as those of the imaging of the chip 21 in the above-mentioned imaging step S2 (see FIG. 15).

[0205] The first side image acquired by the imaging unit 116 is input to an image registration unit 292a included in the setting unit 292 of the control unit 290. Furthermore, the image registration unit 292a receives as input the processing conditions (processing conditions of the workpiece 31 when the first chip is formed) transmitted from the laser processing device 300. Then, the image registration unit 292a registers the first side image of the first chip and the processing conditions used to form the first chip in an image storage unit 296a included in the storage unit 296. As a result, the first side image is stored in the image storage unit 296a in a state linked to the processing conditions.

[0206] Next, the bending strength of the first chip is measured (measurement step S13). In measurement step S13, the first chip whose side surface has been imaged by imaging unit 116 is transported to measuring unit 200 (see FIGS. 2 and 3), and the bending strength of the first chip is measured by measuring unit 200 (see FIGS. 12 to 14).

[0207] The flexural strength of the first tip measured by the measuring unit 200 is input to an intensity registration unit 292b included in the setting unit 292 of the control unit 290. Furthermore, the intensity registration unit 292b receives as input processing conditions (processing conditions of the workpiece 31 when the first tip is formed) transmitted from the laser processing device 300. The strength registration unit 292b then registers the flexural strength of the first tip and the processing conditions used to form the first tip in an intensity storage unit 296b included in the storage unit 296. As a result, the flexural strength of the first tip is stored in the strength storage unit 296b in a state linked to the processing conditions.

[0208] The first imaging step S12 and the measurement step S13 are performed on each of the plurality of workpieces 31 contained in the cassette 8 (see FIGS. 2 and 3). As a result, the image storage unit 296a stores a plurality of first side surface images for each processing condition, and the strength storage unit 296b stores the flexural strengths of the plurality of first chips for each processing condition.

[0209] Next, the processing conditions that can form the first chip with the highest bending strength among the plurality of processing conditions are set as the dividing processing conditions (dividing processing condition setting step S14). In dividing processing condition setting step S14, the processing conditions when processing the workpiece 41 (see FIG. 20(B)) by the laser processing device 300 in a later step are set based on the bending strength of the first chip stored in the strength memory unit 296b.

[0210] Specifically, first, the divided processing condition setting unit 292c included in the setting unit 292 of the control unit 290 reads out the bending strengths of the multiple first tips stored in the strength memory unit 296b for each processing condition. Then, the strength memory unit 296b compares the bending strengths of the multiple first tips and identifies the bending strength of the first tip with the highest bending strength.

[0211] Thereafter, the strength storage unit 296b selects the processing conditions used to form the first chip with the highest flexural strength as the dividing processing conditions, and writes the dividing processing conditions into the dividing processing condition storage unit 296c included in the storage unit 296. As a result, the dividing processing conditions for forming a chip with high flexural strength are registered in the dividing processing condition storage unit 296c.

[0212] Next, a first side image representing a side surface of a first chip formed by processing the first workpiece under the dividing processing conditions is set as a reference image (reference image setting step S15). In the reference image setting step S15, a first side image that serves as a reference for threshold setting, which will be described later, is selected from the plurality of first side images stored in the image storage unit 296a.

[0213] Specifically, first, a reference image setting unit 292d included in the setting unit 292 of the control unit 290 reads out a plurality of first side surface images stored in the image storage unit 296a for each processing condition. The reference image setting unit 292d also reads out the division processing conditions stored in the division processing condition storage unit 296c.

[0214] Thereafter, the reference image setting unit 292d identifies, from among the multiple first side surface images, a first side surface image that shows the side surface of a first chip (the first chip having the highest bending strength) formed by processing the workpiece 31 under the division processing conditions. Then, the reference image setting unit 292d writes the identified first side surface image as a reference image in a reference image storage unit 296d included in the storage unit 296. As a result, the first side surface image of the chip having the highest bending strength is registered as a reference image in the reference image storage unit 296d.

[0215] Next, a threshold value for the evaluation value extracted from the reference image is set (threshold setting step S16). In threshold setting step S16, an evaluation value that serves as a reference for chip evaluation is extracted from the reference image stored in the reference image storage unit 296d, and a threshold value for the evaluation value is set.

[0216] Specifically, first, the threshold setting unit 292e included in the setting unit 292 of the control unit 290 reads out the reference image stored in the reference image storage unit 296d. Then, the reference image storage unit 296d performs image processing on the reference image to extract a predetermined value corresponding to the strength of the chip as the evaluation value. Specific examples of the evaluation value are as described above. For example, a value corresponding to the gradation in the region representing the modified layer in the first side image or a value corresponding to the position of the modified layer represented in the first side image is extracted as the evaluation value (see FIG. 18).

[0217] Next, the threshold setting unit 292e writes the threshold that defines the allowable range of the extracted evaluation value to a threshold storage unit 296e included in the storage unit 296. As a result, the threshold used for evaluating the chip is registered in the threshold storage unit 296e.

[0218] For example, while visually checking the reference image displayed on the display unit 280, the operator selects a range of evaluation values ​​within which the strength of the chip is expected to be maintained at a certain level or higher, and inputs the range into the inspection device 2. Then, the threshold setting unit 292e writes the threshold selected by the operator into the threshold storage unit 296e. However, the threshold setting unit 292e may also write a threshold selected voluntarily in accordance with predetermined conditions into the threshold storage unit 296e.

[0219] The above evaluation condition setting step S10 (first division step S11 to threshold setting step S16) specifies the division processing conditions for obtaining chips with high bending strength, and selects a threshold value for inspecting the state of the chips. The division processing conditions stored in the division processing condition storage unit 296c are then transmitted from the transmitting / receiving unit 298 to the laser processing device 300, and stored in the processing condition storage unit 316a included in the storage unit 316 of the laser processing device 300.

[0220] Next, workpiece 41 (second workpiece, see FIG. 20(B)) is processed under dividing conditions to divide workpiece 41 into a plurality of second chips (second dividing step S21). Workpiece 41 is a product workpiece used to manufacture an actual product. That is, by dividing workpiece 41, second chips to be shipped as actual products are manufactured.

[0221] In the second division step S21, the workpiece 41 is processed by the laser processing device 300, and modified layers are formed inside the workpiece 41 along the streets 43 (see FIG. 16). At this time, the drive control unit 314b included in the processing unit 314 of the laser processing device 300 reads out the division processing conditions transmitted from the inspection device 2 and stored in the processing condition storage unit 316a. Then, the drive control unit 314b outputs control signals to each component of the laser processing device 300 (such as the laser irradiation unit 306) so that the workpiece 41 is processed under the division processing conditions. As a result, the workpiece 41 is processed under the division processing conditions selected to form chips with high strength.

[0222] The workpiece 41 on which the modified layer has been formed is transported to the expansion device 400 (see FIGS. 17(A) and 17(B)), and an external force is applied to the workpiece 41 by the expansion device 400. As a result, the workpiece 41 is divided into a plurality of second chips.

[0223] The details of processing the workpiece 31 by the laser processing device 300 and the expansion device 400 are the same as those of processing the workpiece 11 in the above-mentioned dividing step S1 (see FIG. 15). Then, the workpiece 41 divided into a plurality of second chips is stored in a cassette 8 (see FIGS. 2 and 3) and transported to the inspection device 2.

[0224] Next, the side surface of the second chip is imaged to obtain a second side image representing the side surface of the second chip (second imaging step S22). In the second imaging step S22, the side surface of the second chip is imaged by the imaging unit 116 of the side surface observation mechanism 112. As a result, a second side image representing the side surface of the second chip is obtained (see FIG. 18). Note that the details of the imaging of the second chip by the imaging unit 116 are the same as those of the chip 21 in the imaging step S2 (see FIG. 15) described above.

[0225] Next, the state of the second chip is inspected by comparing the evaluation value extracted from the second side image with a threshold value (inspection step S23). In inspection step S23, a predetermined value corresponding to the intensity of the second chip is extracted from the second side image as an evaluation value. Then, by determining whether the evaluation value is within a predetermined allowable range, it is inspected whether the state of the second chip is normal or abnormal. Note that the details of the inspection of the second chip are the same as those of the chip 21 in the above-mentioned inspection step S3 (see FIG. 15).

[0226] Specifically, the second side image acquired by the imaging unit 116 is input to a side surface inspection unit 294a included in the inspection unit 294 of the control unit 290. Then, the side surface inspection unit 294a extracts an evaluation value from the second side surface image by performing predetermined image processing on the second side surface image. For example, similar to the above-mentioned inspection step S3 (see FIG. 15), a value corresponding to the gradation in the region representing the modified layer in the second side surface image and a value corresponding to the position of the modified layer represented in the second side surface image are extracted as the evaluation value.

[0227] The side surface inspection unit 294a also reads out the threshold value stored in the threshold value storage unit 296e and compares the evaluation value with the threshold value. This determines whether the evaluation value is within a predetermined allowable range. If the evaluation value is within the allowable range, the second chip is determined to be normal, and if the evaluation value is outside the allowable range, the second chip is determined to be abnormal.

[0228] Thereafter, notification unit 294c included in inspection unit 294 outputs a control signal to display unit 280, causing information corresponding to the inspection result to be displayed on display unit 280. In this way, the inspection result of the second chip is notified to the operator (notification step S24).

[0229] If the second chip is determined to be abnormal as a result of the inspection by inspection unit 294, notification unit 294c outputs a control signal to display unit 280 to display error information notifying the abnormality of the second chip. As a result, a warning message notifying the user that the evaluation value is an abnormal value is displayed on display unit 280, for example.

[0230] Furthermore, in addition to the display unit 280, the inspection device 2 may also be provided with an alarm unit (alarm section, alarm device) that notifies the operator of information. For example, an indicator light (warning light) may be provided as the alarm unit. In this case, the notification section 294c notifies the operator of an error by turning on or blinking the indicator light. Furthermore, a speaker may also be provided as the alarm unit. In this case, the notification section 294c notifies the operator of an error by causing the speaker to emit a sound or voice that notifies the operator of an abnormality.

[0231] Furthermore, the results of the inspection by the inspection unit 294 may be transmitted from the transmitting / receiving unit 298 to the laser processing device 300. In this case, the laser processing device 300 may notify the operator of the inspection results of the second chip. For example, the laser processing device 300 is provided with a display unit similar to the inspection device 2, and the control unit 312 causes the display unit to display error information informing the operator of an abnormality in the second chip. This allows the display unit of the laser processing device 300 to display a warning message informing the operator that the evaluation value is an abnormal value, an instruction message prompting the operator to change the processing conditions (laser irradiation conditions, etc.), etc.

[0232] The second chips are inspected through the above evaluation step S20 (second division step S21 to notification step S24). Then, the second chips whose evaluation values ​​are outside the allowable range are excluded as defective chips from the chips for the product.

[0233] In addition to determining the second side image, the second chip may be subjected to measurement of its flexural strength in inspection step S23. In this case, the second chip whose side surface has been imaged by imaging unit 116 is transported to measuring unit 200 (see FIGS. 2 and 3), and measuring unit 200 measures the flexural strength of the second chip (see FIGS. 12 to 14).

[0234] The flexural strength of the second chip measured by the measuring unit 200 is input to a strength inspection unit 294b included in the inspection unit 294 of the control unit 290. Then, the strength inspection unit 294b compares the measured flexural strength of the second chip with a threshold value stored in advance in the memory unit 296, thereby determining whether the flexural strength of the second chip is within a predetermined allowable range.

[0235] Thereafter, the notification unit 294c included in the inspection unit 294 outputs a control signal to, for example, the display unit 280, causing information corresponding to the inspection result of the bending strength by the strength inspection unit 294b to be displayed on the display unit 280. In this way, the inspection result of the second chip is notified to the operator (notification step S24).

[0236] As described above, in the chip inspection method according to this embodiment, the state of the chip is inspected based on the evaluation value extracted from the side image representing the side surface of the chip. This allows for a more detailed understanding of the state of the chip, which cannot be fully evaluated by measuring only the die strength of the chip, and enables appropriate quality evaluation of the chip obtained by dividing the workpiece.

[0237] In the above embodiment, an example in which the workpiece is divided using the laser processing device 300 has been described (see FIG. 16), but the workpiece can also be divided using other processing devices. For example, the workpiece 11 may be divided by cutting the workpiece with a cutting device.

[0238] The cutting device includes a chuck table that holds the workpiece and a cutting unit that cuts the workpiece. The cutting unit has a built-in spindle with an annular cutting blade attached to the tip of the spindle. The workpiece is held on the chuck table, and the cutting blade is rotated while cutting into the workpiece, cutting the workpiece along the streets and dividing it into multiple chips.

[0239] When a workpiece is cut with a cutting blade, chipping remains on the side surface of the chip (the surface to be divided, the surface to be cut). This chipping affects the strength of the chip. Therefore, in inspection step S3 (see FIG. 15) and inspection step S23 (see FIG. 19), values ​​indicating the length, width, position, etc. of the chipping remaining on the chip may be extracted from the side image as evaluation values ​​and used to evaluate the chip.

[0240] Furthermore, in the above embodiment, the case where the side surface of the chip is imaged by the imaging unit 116 provided in the inspection device 2 has been described, but the laser processing device 300 (see FIG. 16) or the extension device 400 (see FIGS. 17(A) and 17(B)) may also be provided with an imaging unit capable of imaging the side surface of the chip. In this case, the laser processing device 300 or the extension device 400 can also be used to inspect the chip.

[0241] In addition, the structures, methods, etc. according to the above-described embodiments can be modified as appropriate without departing from the scope of the object of the present invention. [Explanation of symbols]

[0242] 11 Workpiece 11a Surface (first side) 11b Back side (2nd side) 13th Street (Planned division line) 15 devices 17 frames 17a aperture 19 Tape 21 chips 21a Surface (first side) 21b Back side (2nd side) 21c side 23 Debris 25 Modified layer (degenerated layer) 31 Workpiece (1st workpiece) 31a Surface (first side) 31b Back side (2nd side) 33rd Street (Planned division line) 35 devices 41 Workpiece (second workpiece) 41a Surface (first side) 41b Back side (2nd side) 43rd Street (Planned division line) 45 devices 2. Inspection equipment (measuring equipment, test equipment) 4 Foundation 4a aperture 4b aperture 6 Cassette stand 8 cassettes 10 Temporary placement mechanism 12 Guide rail 12a 1st support surface 12b Second support surface 14 Frame fixing mechanism 16 Frame support 18 Frame holder 18a Notch 20 Transport mechanism 22a 1st grip part 22b Second grip part 30 Moving mechanism 32 X-axis movement mechanism 34 X-axis guide rail 36 X-axis ball screw 38 X-axis pulse motor 40 Moving Plate 42 Y-axis movement mechanism 44 Y-axis guide rail 46 Y-axis ball screw 48 Y-axis pulse motor 50 Push-up mechanism 60 Imaging unit 70 Pickup mechanism 72 Moving Blocks 74 Arm 74a 1st support part 74b Second support part 74c bottom surface 76 Colette 76a Suction surface 80 Collet moving mechanism 82 Y-axis movement mechanism 84 Y-axis guide rail 86 Y-axis ball screw 88 Y-axis pulse motor 90 Moving Plate 92 Z-axis movement mechanism 94 Z-axis guide rail 96 Z-axis ball screw 98 Z-axis pulse motor 100 Chip observation mechanism (chip observation unit) 102 Bottom observation mechanism 104 Support base 106 Support structure 106a Holding surface 108 Imaging unit (bottom imaging unit) 110 Vibration-proof member 112 Side observation mechanism 114 Chip support stand 114a Support surface 116 Imaging unit (side imaging unit) 120 Housing 122 Image sensor 124 Interference Objective Lens 126 Light irradiation unit 128 Half Mirror 130 Piezoelectric element 132 Power supply 134 Objective Lens 136 Glass Plate 138 Reference Mirror 140 Half Mirror 150 Chip inversion mechanism 150a base 150b connection 150c chip holder 150d retaining surface 200 Measurement unit (measuring mechanism) 204 Lower container (container) 204a Top side 204b aperture 204c Lower surface (bottom surface) 204d outlet 206 Support Unit 208 Support stand 208a Top side 208b Support part 210 Gap 212 Contact member 212a Contact surface 214 Support platform movement mechanism 216 Support structure 218 Guide Rail 220 ball screw 222 Pulse motor 224 Moving Plate 226 Pressing unit 228 Mobile Base 230 first support member 232 Load measuring instrument 234 Second support member 236 Clamping member 236a Clamping surface 238 Indenter 240 Moving mechanism 242 Support structure 244 Guide Rail 246 Ball Screw 248 Pulse motor 250 connecting members 250a Upper container support 252 Upper container (cover) 252a Bottom side 252b aperture 252c top surface 252d Indenter insertion hole 252e side wall 252f Nozzle insertion hole 254 Gas Supply Unit 256 nozzles 256a Tip 258 Valve 260 Gas Supply Source 262 Discharge Unit 264 Exhaust channel 266 Valve 268 Suction source 270 Recovery Department 272 Imaging unit 274 Light source 280 Display unit (display unit, display device) 290 Control unit (control unit, control device) 292 Settings 292a Image Registration Section 292b Strength registration section 292c Split processing condition setting section 292d Reference image setting section 292e Threshold setting unit 294 Inspection Department 294a Side Inspection Department 294b Strength Inspection Department 294c Notification Department 296 Memory section 296a Image storage unit 296b Strength memory section 296c Split processing condition storage section 296d Reference image storage unit 296e Threshold memory unit 298 Transmitter / Receiver 300 Laser Processing Equipment 302 Chuck table (holding table) 302a retaining surface 304 Clamp 306 Laser irradiation unit 308 Laser Processing Head 310 Laser Beam 312 Control unit (control unit, control device) 314 Processing Unit 314a Machining condition setting section 314b Drive control unit 316 Storage section 316a Machining condition memory section 318 Transmitter / Receiver 400 Expansion Unit 402 Drums 404 Coro 406 Support member 408 Table 408a aperture 410 Clamp 500 side images 500a area

Claims

1. a dividing step of dividing the workpiece into a plurality of chips by processing the workpiece under predetermined dividing processing conditions; an imaging step of imaging a side surface of the chip to obtain a side image representing the side surface of the chip; an inspection step of inspecting the state of the chip by comparing an evaluation value extracted from the side image with a threshold value; The dividing step includes a modified layer forming step of forming a modified layer inside the workpiece along the street by irradiating a laser beam that is transparent to the workpiece along the street, and an external force applying step of dividing the workpiece along the street starting from the modified layer by applying an external force to the workpiece, A chip inspection method characterized in that the evaluation value is a value corresponding to the gradation in the area representing the modified layer in the side image, or a value corresponding to the position of the modified layer represented in the side image.

2. a first dividing step of dividing a plurality of first workpieces into a plurality of first chips by machining the plurality of first workpieces under a plurality of machining conditions; a first imaging step of capturing an image of a side surface of the first chip to obtain a first side image representing the side surface of the first chip; a measuring step of measuring the flexural strength of the first chip; a dividing processing condition setting step of setting a processing condition that can form the first tip having the highest bending strength among the plurality of processing conditions as a dividing processing condition; a reference image setting step of setting the first side image representing a side surface of the first chip formed by processing the first workpiece under the dividing processing conditions as a reference image; a threshold setting step of setting a threshold for the evaluation value extracted from the reference image; a second dividing step of dividing the second workpiece into a plurality of second chips by machining the second workpiece under the dividing machining conditions; a second imaging step of capturing an image of a side surface of the second chip to obtain a second side image representing the side surface of the second chip; and an inspection step of inspecting the state of the second chip by comparing the evaluation value extracted from the second side image with the threshold value.

Images