Processing device

Abstract

To reduce an investigation time required to determine whether defects occurring in a processed workpiece after processing are caused by processing in a processing device.SOLUTION: A processing device includes a holding unit, a processing unit, a processing feed unit, a first imaging unit, a second imaging unit, and a controller. A first imaging area captured by the first imaging unit is positioned on the opposite side to a second imaging area captured by the second imaging unit in a processing feed direction with a processing area as a center. When processing a workpiece, the controller causes one of the first imaging unit and the second imaging unit whose imaging area is located at a front of a moving direction of the processing area, to image a target area including an unprocessed area of the workpiece before processing to obtain a pre-processing image of the target area, and causes the other imaging unit whose imaging area is located at a rear of the moving direction of the processing area, to image the target area after processing to obtain a post-processing image of the target area.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a processing device that is capable of processing a workpiece and capturing an image of the workpiece. [Background technology]

[0002] In order to manufacture semiconductor device chips, a semiconductor wafer on which a plurality of devices are formed is divided into individual devices. A plurality of division lines are usually set in a grid pattern on the surface of the semiconductor wafer, and the above-mentioned devices are provided in each of the rectangular regions defined by the division lines.

[0003] One method for dividing a semiconductor wafer into device units is to irradiate a laser beam having a wavelength that is absorbed by the semiconductor wafer along each intended dividing line, and divide the semiconductor wafer into device units by ablation processing (see, for example, Patent Document 1).

[0004] Another method involves irradiating a laser beam having a wavelength that can pass through the semiconductor wafer along each planned dividing line to form a modified layer with relatively weak mechanical strength inside the semiconductor wafer, and then applying an external force to the semiconductor wafer to divide the semiconductor wafer into device units (see, for example, Patent Document 2).

[0005] Such laser processing is usually performed using a laser processing device, but the semiconductor wafer may already have defects in some areas before being processed by the laser processing device. For example, a thin film formed on one surface of the semiconductor wafer may already have peeled off in some areas before the laser processing.

[0006] When such a defect is discovered after the laser processing step, it may be difficult to investigate after the fact whether the defect already occurred before the laser processing step or whether it is a processing defect caused by the laser processing step, and furthermore, since the investigation takes time, there is a problem that productivity decreases by conducting the investigation. Note that this is not limited to laser processing devices, but also applies to cutting devices that cut workpieces with an annular cutting blade. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-320466 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-192370 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the above problems, and aims to reduce the investigation time required to determine whether defects occurring in a workpiece after processing are caused by processing in a processing device. [Means for solving the problem]

[0009] According to one aspect of the present invention, a processing apparatus includes a holding unit that holds a workpiece, a processing unit that processes the workpiece held by the holding unit, a processing feed unit that moves the holding unit and the processing unit relatively along a processing feed direction, a first imaging unit having a first imaging element and moving together with the processing unit relative to the holding unit by the processing feed unit, a second imaging unit having a second imaging element and moving together with the processing unit and the first imaging unit relative to the holding unit by the processing feed unit, and a controller having a processor and a memory and controlling the operations of the processing unit, the processing feed unit, the first imaging unit, and the second imaging unit, is arranged on the opposite side in the processing feed direction to the second imaging area of ​​the second imaging unit, centered on a processing area where processing is performed on the workpiece by the processing unit, and when the workpiece is processed while the holding unit and the processing unit are moved relatively along the processing feed direction, the controller causes one of the first imaging unit and the second imaging unit, whose imaging area is located in front of the movement direction of the processing area, to image a target area including an unprocessed area of ​​the workpiece before processing, to obtain a pre-processing image of the target area, and causes the other of the first imaging unit and the second imaging unit, whose imaging area is located behind the movement direction of the processing area, to image the target area after processing, to obtain a post-processing image of the target area.

[0010] Preferably, the processing device further includes a display device for displaying an image, and the controller causes the display device to display at least one of the pre-processed image and the processed image.

[0011] Preferably, the processing apparatus further includes an input device for an operator to input instructions to the controller, and when one of a plurality of areas on one surface of the workpiece is selected via the input device, the controller simultaneously displays both the pre-processing image and the post-processing image of each selected area on the display device.

[0012] In addition, preferably, the processing apparatus further includes an input device for an operator to input instructions to the controller, and the controller causes the display device to not display the processed image but display the pre-processed image in response to a first instruction input via the input device, and causes the display device to not display the pre-processed image but display the processed image in response to a second instruction input via the input device.

[0013] Preferably, the controller analyzes the results of processing the workpiece by the processing unit in the target area based on the before-processing image and the after-processing image. [Effects of the Invention]

[0014] A controller of a processing device according to one aspect of the present invention causes one imaging unit, whose imaging area is located in front of the direction of movement of the processing area, to capture an image of a target area including an unprocessed area of ​​the workpiece before processing, to obtain a pre-processing image of the target area, and causes the other imaging unit, whose imaging area is located behind the direction of movement of the processing area, to capture an image of the target area after processing, to obtain a post-processing image of the target area.

[0015] By comparing the pre-processing image with the post-processing image, the processing device can determine whether or not a defect has occurred in the workpiece due to processing by the processing device.Therefore, the investigation time required to determine whether or not a defect has occurred in the processed workpiece due to processing by the processing device can be reduced compared to when the pre-processing image obtained by another device and the post-processing image obtained by the processing device are collected in a designated device such as a PC (Personal Computer) and then the two images are compared.

[0016] Furthermore, compared to capturing an image of the workpiece before processing by the processing device to capture a pre-processing image of the workpiece, then processing the workpiece along the planned division line using the processing device, and then capturing a post-processing image of the planned division line after processing, the pre-processing image can be captured, the workpiece is processed, and the post-processing image can be captured in a single operation, allowing the workpiece to be processed and the image to be captured efficiently. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 2 is a perspective view of the laser processing device. [Figure 2] FIG. [Figure 3] Figure 3(A) is a schematic diagram showing the position of the head unit etc. at time t1, Figure 3(B) is a schematic diagram showing the position of the head unit etc. at time t2, and Figure 3(C) is a schematic diagram showing the position of the head unit etc. at time t3. [Figure 4] FIG. 2 is a schematic diagram illustrating an example of a display screen of a touch panel display. [Figure 5] FIG. 10 is a schematic diagram showing an example of a display screen that simultaneously and separately displays both an unprocessed image and a processed image. [Figure 6] FIG. 6(A) is a schematic diagram showing an example of a display screen that selectively displays only the pre-processed image, and FIG. 6(B) is a schematic diagram showing an example of a display screen that selectively displays only the post-processed image. [Figure 7] Figure 7(A) is a schematic diagram showing an example of an image before processing, Figure 7(B) is a schematic diagram showing an example of an image after processing, and Figure 7(C) is a schematic diagram showing an example of an analysis image for analyzing the results of processing. [Figure 8] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] (First embodiment) An embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view of a laser processing device (processing device) 2. In Fig. 1, some of the components of the laser processing device 2 are shown in functional blocks.

[0019] 1, the X-axis (axis parallel to the machining feed direction), the Y-axis (axis parallel to the indexing feed direction), and the Z-axis (axis parallel to the height direction) are perpendicular to one another. The +X direction and the -X direction are both parallel to the X-axis but are opposite to one another. In this specification, the +X direction and the -X direction may be collectively referred to as the X-axis direction.

[0020] Similarly, the +Y direction and the -Y direction are both parallel to the Y axis but are opposite to each other, and the +Z direction and the -Z direction are both parallel to the Z axis but are opposite to each other. In this specification, the +Y direction and the -Y direction are sometimes collectively referred to as the Y axis direction, and the +Z direction and the -Z direction are sometimes collectively referred to as the Z axis direction.

[0021] The laser processing device 2 includes a base 4 that supports each component. The base 4 includes a rectangular parallelepiped base 6 and a wall 8 that extends upward from one end of the base 6. A disk-shaped chuck table (holding unit) 10 is provided on the base 6. The chuck table 10 has a disk-shaped frame.

[0022] A disk-shaped recess is provided in the radial center of the frame. A porous plate made of porous ceramics or the like and having an outer diameter approximately the same as that of the recess is fixed in this recess. The upper surface of the frame and the upper surface of the porous plate are flush with each other, forming a substantially flat holding surface 10a that is disposed approximately parallel to the XY plane.

[0023] When a negative pressure is transmitted from a suction source (not shown) such as a vacuum generator to the porous plate via the frame, the negative pressure is also transmitted to the holding surface 10a. Below the holding surface 10a, multiple pairs of beams (four pairs in this embodiment) are provided so as to extend outward from the center of the chuck table 10 in the radial direction.

[0024] The base end of each beam is fixed to the chuck table 10. The tip of each beam is provided with a clamp unit 10b for fixing an annular frame 19 (described later) to the chuck table 10.

[0025] A Y-axis movement unit 12 that moves the chuck table 10 in the Y-axis direction is provided below the chuck table 10. The Y-axis movement unit 12 has a pair of guide rails 14 that are fixed to the upper surface of the base 6 and arranged parallel to the Y-axis direction.

[0026] A Y-axis direction moving table 16 is slidably attached to the pair of guide rails 14. A nut portion (not shown) is provided on the underside of the Y-axis direction moving table 16, and a screw shaft 18, which is arranged substantially parallel to the Y-axis direction, is rotatably coupled to this nut portion via a plurality of balls (not shown).

[0027] A motor 20 such as a servo motor or a stepping motor is connected to one end of the screw shaft 18. When the screw shaft 18 is rotated by the motor 20, the Y-axis direction moving table 16 moves along the Y-axis direction.

[0028] An X-axis direction moving unit (processing feed unit) 22 is provided on the upper surface of the Y-axis direction moving table 16. The X-axis direction moving unit 22 includes a pair of guide rails 24 that are fixed to the upper surface of the Y-axis direction moving table 16 and arranged parallel to the X-axis direction.

[0029] An X-axis direction moving table 26 is slidably attached to the pair of guide rails 24. A nut portion (not shown) is provided on the underside of the X-axis direction moving table 26, and a screw shaft 28, which is arranged substantially parallel to the X-axis direction, is rotatably coupled to this nut portion via a plurality of balls (not shown).

[0030] A motor 30 such as a servo motor or a stepping motor is connected to one end of the screw shaft 28. When the screw shaft 28 is rotated by the motor 30, the X-axis direction moving table 26 moves along the X-axis direction.

[0031] A cylindrical support base 32 is provided on the upper surface of the X-axis direction moving table 26. The above-mentioned chuck table 10 is provided on the top of the support base 32. A rotary drive source (not shown) such as a motor is provided inside the support base 32, and the chuck table 10 can be rotated by this rotary drive source around a rotation axis that is approximately parallel to the Z-axis direction.

[0032] A workpiece 11 is held by suction on the chuck table 10. The workpiece 11 has a thickness (i.e., the length from the front surface 11a to the back surface 11b) of approximately 500 μm to 1000 μm. In this example, the workpiece 11 has a disk-shaped single crystal silicon substrate (i.e., a silicon wafer).

[0033] There are no limitations on the material, shape, structure, size, etc. of the workpiece 11. For example, the workpiece 11 may be a semiconductor wafer formed of a semiconductor material other than silicon, such as gallium nitride (GaN), gallium arsenide (GaAs), or silicon carbide (SiC), or may be a glass substrate, a metal substrate, or the like.

[0034] 2 is a top view of the workpiece 11. A plurality of planned division lines 13 (streets) are set in a grid pattern on the surface (one side) 11a of the workpiece 11. Each planned division line 13 is a strip-shaped region extending linearly.

[0035] Devices 15 such as ICs (Integrated Circuits) and MEMS (Micro Electro Mechanical Systems) are formed in each of the rectangular regions defined by the planned dividing lines 13. There are no restrictions on the type, number, shape, structure, size, arrangement, etc. of the devices 15. The workpiece 11 does not necessarily have to have any devices 15 formed thereon.

[0036] 1, the workpiece 11 is processed by the laser processing device 2 while being integrated with the resin tape 17 and the metal annular frame 19. When integrating these, the workpiece 11 is placed in the opening of the annular frame 19, and tape 17, which has a larger diameter than the workpiece 11, is attached to the back surface 11b of the workpiece 11 and one surface of the annular frame 19.

[0037] This forms a workpiece unit 21 in which the workpiece 11 is supported by the annular frame 19 via the tape 17. After the workpiece unit 21 is placed on the holding surface 10a, the workpiece 11 is suction-held by the holding surface 10a via the tape 17, and the annular frame 19 is held by clamping one surface and the other surface between the clamp units 10b. At this time, the surface 11a is exposed upward.

[0038] A laser beam irradiation unit 34 (that is, a processing unit) is provided above the chuck table 10. The laser beam irradiation unit 34 has a laser oscillator (not shown) fixed to the base 4.

[0039] The laser oscillator has, for example, a crystal such as Nd:YAG as a laser medium, and emits a pulsed laser beam having a wavelength (1064 nm in this example) that passes through the workpiece 11 (a silicon single crystal substrate in this example) by irradiating the crystal with excitation light from a light source such as a flash lamp or a laser diode.

[0040] The pulsed laser beam emitted from the laser oscillator is converted into a predetermined harmonic (for example, a third harmonic with a wavelength of 355 nm) by a wavelength conversion element (not shown) having a nonlinear optical crystal, and then irradiated approximately perpendicularly onto the holding surface 10a from a head portion 36 provided at the tip of the beam-shaped support arm 8a.

[0041] In this embodiment, the workpiece 11 is processed by ablation processing, so a pulsed laser beam L having a wavelength (e.g., 355 nm) that is absorbed by the workpiece 11 is irradiated from the head unit 36 ​​(see Figure 3(A), etc.).

[0042] However, the workpiece 11 may be processed by irradiating it from the head unit 36 ​​with a pulsed laser beam L having a wavelength (for example, 1064 nm) that is transparent to the workpiece 11. In this case, the pulsed laser beam L is irradiated from the head unit 36 ​​without being subjected to wavelength conversion after being emitted from the laser oscillator.

[0043] The head unit 36 ​​has a condensing lens (not shown) that condenses the laser beam L. The position of the head unit 36 ​​in the Z-axis direction is configured to be adjustable by an actuator (not shown), and the position of the condensing point of the laser beam L in the Z-axis direction is adjusted according to the position of the head unit 36.

[0044] For example, with the focal point of the pulsed laser beam L positioned at a predetermined height on or near the surface 11a of the workpiece 11, the chuck table 10 is moved along the X-axis direction by the X-axis direction moving unit 22. In this manner, the chuck table 10 and the head portion 36 (i.e., the processing unit) are moved relatively along the X-axis direction, whereby laser processing of the workpiece 11 is performed.

[0045] A first imaging unit 38 is provided at the tip of the support arm 8a, adjacent to the head unit 36 ​​in the +X direction. The first imaging unit 38 is a so-called microscope camera unit, and is an area sensor camera that can capture an image of a predetermined range of several hundred μm to several mm square. The position of the first imaging unit 38 in the Z-axis direction is configured to be adjustable by an actuator (not shown).

[0046] The first imaging unit 38 has a light source including an LED (Light Emitting Diode) for irradiating light such as visible light onto the subject, a predetermined optical system including a lens, and a solid-state imaging element (first imaging element) 38a for photoelectrically converting reflected light from the subject that is captured via the predetermined optical system.

[0047] A second imaging unit 40 is provided at the tip of the support arm 8a, adjacent to the head unit 36 ​​in the -X direction. The second imaging unit 40 is also a so-called microscope camera unit, and is an area sensor camera that can capture an image of a predetermined range of several hundred μm to several mm square.

[0048] The position of the second imaging unit 40 in the Z-axis direction is adjustable by an actuator (not shown). The second imaging unit 40 can capture an image of the same size and at the same magnification as the first imaging unit 38.

[0049] Similar to the first imaging unit 38, the second imaging unit 40 also has a light source including an LED, a predetermined optical system including a lens, a solid-state imaging element (second imaging element) 40a, etc. The first imaging unit 38 and the second imaging unit 40 are fixed to the tip of the support arm 8a together with the head portion 36.

[0050] That is, in the XY plane, the relative positions of the head portion 36, the first imaging unit 38, and the second imaging unit 40 are fixed. Therefore, when the chuck table 10 is moved by the X-axis direction moving unit 22, the first imaging unit 38 and the second imaging unit 40 move relative to the chuck table 10 together with the head portion 36.

[0051] Exterior panels (not shown) are provided on the sides and above the base 4, and these exterior panels form the side and top surfaces of the laser processing device 2. A touch panel display 42 is provided on one side of the laser processing device 2.

[0052] The touch panel display 42 functions as an input device for the operator to input instructions to the controller 44 described later, and also functions as a display device that displays a GUI (Graphical User Interface), images obtained by the first imaging unit 38 and the second imaging unit 40, processing conditions, the results of image analysis by the controller 44, etc.

[0053] Note that instead of the touch panel display 42, a display device that does not have the function of an input device may be provided in the laser processing device 2. In this case, however, an input device (keyboard, mouse, trackball, touchpad, digitizer, etc.) for the operator to input instructions to the controller 44 is separately provided.

[0054] The operation of the Y-axis direction moving unit 12, the X-axis direction moving unit 22, the rotational drive source in the support base 32, the laser beam irradiation unit 34, the first imaging unit 38, the second imaging unit 40, the clamp unit 10b, etc., as well as whether or not negative pressure is transmitted to the holding surface 10a, are controlled by a controller 44.

[0055] The controller 44 is configured by a computer including a processor 44a, such as a CPU (Central Processing Unit), and a memory 44b. The memory 44b includes a main storage device such as a DRAM (Dynamic Random Access Memory), and an auxiliary storage device such as a flash memory, a hard disk drive, or a solid state drive.

[0056] The auxiliary storage device stores software including a predetermined program. The functions of the controller 44 are realized by operating the processor 44a and the like in accordance with this software. Next, laser processing of the workpiece 11 will be described with reference to FIGS. 2 and 3.

[0057] When performing laser processing on the workpiece 11, first, the first imaging unit 38 or the second imaging unit 40 is used to image the surface 11a of the workpiece 11 (for example, an alignment mark (not shown) located near the planned division line 13) held by suction on the chuck table 10.

[0058] Then, using the image obtained by imaging, the orientation of the chuck table 10 is adjusted by rotating the chuck table 10 with a rotary drive source in the support base 32 so that the planned division line 13 along the first direction is approximately parallel to the X-axis direction.

[0059] Next, the focal point of the laser beam L is positioned at a height near the surface 11a, and the chuck table 10 is moved in the -X direction so that the focal point moves from one end to the other end in the X-axis direction at the intended division line 13 located at the end in the -Y direction.

[0060] At this time, the focal point moves relatively in the +X direction (see the movement locus L1 in FIG. 2). P The movement direction of the object (see FIG. 3(A) etc.) is the +X direction.

[0061] Next, the chuck table 10 is indexed and fed in the -Y direction by a predetermined index amount, so that the light condensing point is positioned on an extension of the dividing line 13 adjacent in the +Y direction to the dividing line 13 located at the end in the -Y direction.

[0062] Then, the chuck table 10 is moved in the +X direction so that the focal point moves from one end to the other end in the X-axis direction along the planned division line 13. At this time, the focal point moves relatively in the -X direction (see the movement locus L2 in FIG. 2). P The movement direction is the -X direction.

[0063] Similarly, the focal point is moved alternately in the +X direction and the −X direction along each of the division lines 13, and laser processing is performed along all the remaining division lines 13 along the first direction (movement locus L3 to L4 in FIG. 2). 11 reference).

[0064] Next, after rotating the chuck table 10 by 90 degrees, laser processing is similarly performed on all of the division lines 13 along a second direction perpendicular to the first direction. An example of processing conditions is shown below.

[0065] Wavelength: 355nm Average power: 5.0W Repetition frequency: 100kHz Processing feed rate: 500mm / s Defocus amount: +10 μm (i.e., the focal point is 10 μm above the surface 11 a)

[0066] In this embodiment, simultaneously with laser processing, the first imaging unit 38 and the second imaging unit 40 capture images of the surface 11a of the workpiece 11 at a predetermined period T. The period T may be determined as appropriate, but in this embodiment, the period T is set to 200 ms.

[0067] As described above, the first imaging unit 38 and the second imaging unit 40 are located at opposite positions in the X-axis direction across the head unit 36. Therefore, the first imaging region R1 captured by the first imaging unit 38 is located at a larger area than the processing region R2 captured by the second imaging unit 40. P are located on the opposite side in the X-axis direction with respect to the center.

[0068] Next, referring to Figures 3(A) to 3(C), we will explain how the first imaging unit 38 and the second imaging unit 40 acquire images of the surface 11a when laser processing the workpiece 11 while moving the chuck table 10 and the head unit 36 ​​relatively along the X-axis direction.

[0069] In the description of FIGS. 3A to 3C, when the head part 36, the first imaging unit 38, and the second imaging unit 40 move in the +X direction relative to the surface 11a, that is, when the second imaging area R2 by the second imaging unit 40 is within the processing area R P The first imaging unit 38 is positioned in front of the processing area R PThis section describes the case where the robot is positioned behind the robot in the direction of movement.

[0070] 3A is a schematic diagram showing the positions at time t1 of the head portion 36, the first imaging unit 38, and the second imaging unit 40. The position of the second imaging unit 40 in the X-axis direction at time t1 is x1.

[0071] At time t1, the controller 44 causes the second imaging unit 40 to acquire an image. Position x1 at time t1 is an unprocessed area of ​​the workpiece 11 before laser processing, where the head unit 36 ​​irradiating the laser beam L has not yet passed. The controller 44 causes the second imaging unit 40 to capture an image of the target area including this unprocessed area.

[0072] 3B is a schematic diagram showing the positions of the head portion 36, the first imaging unit 38, and the second imaging unit 40 at time t2. Time t2 is the point in time when the period T has elapsed since time t1.

[0073] At time t2, the position of the first imaging unit 38 in the X-axis direction is the above-mentioned x1, and the position of the second imaging unit 40 in the X-axis direction is x2, which is located in the +X direction from x1. In this example, (x2 - x1) is 100 mm (= processing feed rate 500 mm / s × period T 200 ms). However, of course, the processing feed rate and period T may be changed as appropriate.

[0074] At time t2, the controller 44 also causes the second imaging unit 40 to capture an image. The position x2 at time t2 is also before the head unit 36 ​​irradiating the laser beam L passes through, and is an unprocessed area of ​​the workpiece 11 before laser processing.

[0075] 3(B) shows a schematic diagram of a pre-processing image 46A of the target area obtained by the second imaging unit 40. This pre-processing image 46A captures a defective area 23 where the thin film has partially peeled off outside the width direction (+Y direction) of the planned division line 13.

[0076] At time t2, the controller 44 also causes the first imaging unit 38 to capture an image. At time t2, the head 36 irradiating the laser beam L has passed position x1, so position x1 is in the post-machining area of ​​the workpiece 11. The controller 44 causes the first imaging unit 38 to capture an image of this post-machining target area.

[0077] 3C is a schematic diagram showing the positions of the head portion 36, the first imaging unit 38, and the second imaging unit 40 at time t3. Time t3 is the point in time when a further period T has elapsed since time t2.

[0078] That is, time t3 is (t1+2T). At time t3, the position of the first imaging unit 38 in the X-axis direction is x2, and the position of the second imaging unit 40 in the X-axis direction is x3. (x3-x2) is also 100 mm.

[0079] At time t3, the controller 44 also causes the second imaging unit 40 to acquire an unprocessed image 46A of the target area including position x3, and causes the first imaging unit 38 to acquire an processed image 46B of the target area including position x2.

[0080] The right side of Figure 3(C) shows a schematic diagram of a processed image 46B of the target area obtained by the first imaging unit 38. In addition to the defective area 23, this processed image 46B captures the processed groove 25 formed by the ablation process.

[0081] The width of the groove 25 (i.e., the length in the +Y direction) is narrower than the width of the planned division line 13. A plurality of chippings (i.e., notches) 27 are formed discretely on both sides of the groove 25 along the longitudinal direction of the groove 25.

[0082] By comparing the before-processing image 46A with the after-processing image 46B in the laser processing device 2, the laser processing device 2 can determine whether or not a defect has occurred in the workpiece 11 due to the laser processing in the laser processing device 2.

[0083] Therefore, the investigation time required to determine whether defects occurring in the workpiece 11 after processing are caused by processing by the laser processing device 2 can be reduced compared to when the pre-processing image 46A obtained by another device and the post-processing image 46B obtained by the laser processing device 2 are collected in a designated device such as a PC and then the two images are compared.

[0084] Furthermore, compared to capturing an image of the planned division line 13 before processing with the laser processing device 2 to obtain a pre-processing image 46A of the workpiece 11, then performing laser processing on the planned division line 13 of the workpiece 11 with the laser processing device 2, and then obtaining a post-processing image 46B of the planned division line 13 after laser processing, the acquisition of the pre-processing image 46A, laser processing of the workpiece 11, and acquisition of the post-processing image 46B can be achieved in a single operation, allowing the processing of the workpiece 11 and image acquisition to be carried out efficiently.

[0085] In the above example, the processing area R P In the above description, the movement direction of the head 36 and the like is in the +X direction. However, the head 36 and the like move in the -X direction relative to the surface 11a (i.e., the processing area R P When the movement direction of the first imaging unit 38 is the -X direction, the first imaging region R1 of the first imaging unit 38 is located in the processing region R P The second imaging area R2 of the second imaging unit 40 is located in front of the processing area R P The robot will be positioned behind the robot in the direction of movement.

[0086] Next, a method for displaying a pre-processing image 46A and a post-processing image 46B and a method for analyzing the results of processing will be described with reference to Figures 4 to 7. Figure 4 is a schematic diagram showing an example of the display screen of the touch panel display 42 that displays the entire processing surface (surface 11a in this embodiment) of the workpiece 11 that has been subjected to laser processing.

[0087] In the example shown in Fig. 4, the entire surface 11a is divided into a plurality of rectangular regions (i.e., a plurality of regions) 29 each of which is substantially in the normal direction. For the sake of convenience, two rectangular regions 29 are highlighted in Fig. 4. However, the actual rectangular regions 29 are not highlighted.

[0088] When the worker selects one of the rectangular areas 29 via the touch panel display 42, the controller 44 causes the touch panel display 42 to display at least one of the pre-processed image 46A and the post-processed image 46B of the selected rectangular area 29.

[0089] The area of ​​each rectangular area 29 is usually larger than the imaging areas of the first imaging unit 38 and the second imaging unit 40. The size of each rectangular area 29 is, for example, 30 mm square, but this size can be changed as appropriate.

[0090] In this embodiment, as described above, images are captured at a pitch of 100 mm, so that for every three consecutive rectangular areas 29 in a direction parallel to the planned division line 13, one rectangular area 29 contains a set of pre-processing image 46A and post-processing image 46B.

[0091] However, the pitch of the imaging positions may be adjusted so that each rectangular area 29 contains one set of pre-processed image 46A and post-processed image 46B, or the pitch of the imaging positions may be adjusted so that each rectangular area 29 contains multiple sets of pre-processed image 46A and post-processed image 46B.

[0092] Instead of dividing the entire surface 11a into a plurality of rectangular regions 29, a plurality of rectangular regions 29 each including at least one set of an unprocessed image 46A and an processed image 46B may be displayed discretely on the surface 11a.

[0093] When the worker selects any of the rectangular areas 29 via the touch panel display 42, the controller 44 simultaneously displays both the pre-processed image 46A and the post-processed image 46B of each selected rectangular area 29 on the touch panel display 42, as shown in, for example, FIG. 5.

[0094] Fig. 5 is a schematic diagram showing an example of a display screen that simultaneously and separately displays both a pre-processing image 46A and a post-processing image 46B. In the example shown in Fig. 5, the processing conditions used in the laser processing are also displayed.

[0095] This display mode allows the worker to immediately and clearly understand whether or not a defect occurring in the workpiece 11 after processing is caused by processing by the laser processing device 2. Note that the display mode when the rectangular area 29 is selected is not limited to this.

[0096] For example, both the pre-processing image 46A and the post-processing image 46B can be displayed superimposed simultaneously. In this case, one of the pre-processing image 46A and the post-processing image 46B is displayed superimposed on the other, which has been processed into a semi-transparent image. In this case, a portion of the superimposed images may be highlighted so that the non-overlapping area (e.g., the processing groove 25) is emphasized.

[0097] Figure 6(A) is a schematic diagram showing an example of a display screen that selectively displays only the pre-processed image 46A in the rectangular area 29, and Figure 6(B) is a schematic diagram showing an example of a display screen that selectively displays only the post-processed image 46B in the rectangular area 29.

[0098] In the examples shown in FIGS. 6(A) and 6(B), switching between the pre-processed image 46A and the post-processed image 46B can be performed by radio buttons 50a and 50b displayed on the screen as a GUI.

[0099] In other words, in response to a first instruction input by the worker via the touch panel display 42 (i.e., pressing the radio button 50a corresponding to "before processing image"), the controller 44 causes the touch panel display 42 to display the before processing image 46A without displaying the after processing image 46B.

[0100] Similarly, in response to a second instruction input by the worker via the touch panel display 42 (i.e., pressing the radio button 50b corresponding to "processed image"), the controller 44 causes the touch panel display 42 to not display the pre-processed image 46A but to display the processed image 46B.

[0101] This type of switching display also allows the operator to understand whether or not defects occurring in the workpiece 11 after processing are caused by processing by the laser processing device 2. The processing conditions used in the laser processing may also be displayed on the display screen.

[0102] In addition to the function of displaying the before-processing image 46A, the after-processing image 46B, etc. on the touch panel display 42, the controller 44 also has the function of analyzing the results of laser processing by the laser beam irradiation unit 34 in the target area from which the before-processing image 46A and the after-processing image 46B were obtained based on the before-processing image 46A and the after-processing image 46B.

[0103] The function for analyzing the results of laser processing is stored as a predetermined program in the auxiliary storage area. The predetermined program has at least an image processing function. For example, the predetermined program calculates the difference between a pre-processing image 46A (see FIG. 7(A)) and a post-processing image 46B (see FIG. 7(A)), and then displays an analysis image 46C reflecting the difference between the two on the touch panel display 42 (see FIG. 7(C)).

[0104] Furthermore, for example, a predetermined program extracts the first processing groove 25a, defective area 23, etc., which are each previously included in the pre-processing image 46A (see Figure 7(A)) by image processing, removes the first processing groove 25a, defective area 23, etc. from the post-processing image 46B (see Figure 7(B)) by masking processing, and then displays an analysis image 46C, which has only the second processing groove 25b in the post-processing image 46B, on the touch panel display 42 (see Figure 7(C)).

[0105] Figure 7(A) is a schematic diagram showing an example of a pre-processing image 46A, Figure 7(B) is a schematic diagram showing an example of a post-processing image 46B, and Figure 7(C) is a schematic diagram showing an example of an analysis image 46C for analyzing the results of processing.

[0106] In Figure 7(C), (i) the protrusion amount 27a of the chipping 27 that protrudes outward in a direction perpendicular to the linear edge 31 of the machining groove 25b along the machining feed direction, (ii) the width 33 of the machining groove 25b including the protrusion amount 27a of the chipping 27, (iii) the number of chippings 27, (iv) the maximum value of the protrusion amount 27a of the chipping 27, etc. are analyzed by the controller 44 using image processing.

[0107] The controller 44 may compare the results of the analysis with the predetermined allowable values ​​of (i) the value of the protrusion amount 27a, (ii) the value of the width 33, (iii) the number of chippings 27, and (iv) the maximum value of the protrusion amount 27a, and determine whether the results of the laser processing when forming the processing groove 25b are good or bad.

[0108] Second Embodiment Next, a second embodiment will be described with reference to Fig. 8. In the second embodiment, a cutting device (processing device) 52 is used instead of the laser processing device 2 to acquire a pre-processing image 46A and a post-processing image 46B, and the two images are compared in the cutting device 52.

[0109] Fig. 8 is a perspective view of the cutting device 52. In Fig. 8, some of the components of the cutting device 52 are shown in functional blocks. The cutting device 52 includes a base 54 that supports the components. An opening 54a is formed in a corner of the base 54, and a cassette elevator 56 that moves up and down by an elevating mechanism (not shown) is provided within this opening 54a.

[0110] A cassette 58 containing the above-described plurality of workpiece units 21 is placed on the upper surface of cassette elevator 56. An opening 54b is formed in the −Y direction of cassette elevator 56, with its longitudinal direction aligned with the X-axis direction.

[0111] An X-axis direction moving unit (i.e., a processing feed unit) substantially the same as the above-described X-axis direction moving unit 22 is provided below the opening 54b (not shown in FIG. 8). An X-axis direction moving table of the X-axis direction moving unit is provided with a support base (not shown) similar to the above-described support base 32.

[0112] The chuck table 64 can be moved along the X-axis direction by an X-axis direction moving unit, and can be rotated around a rotation axis approximately parallel to the Z-axis direction by a rotary drive source provided on the support base.

[0113] A rectangular table cover 60 is provided above the support stand. In the X-axis direction, an expandable and contractible bellows-shaped cover member 62 is provided between the table cover 60 and the opening 54b. The table cover 60 and cover member 62 cover the X-axis direction movement unit of the cutting device 52.

[0114] A disk-shaped chuck table (holding unit) 64 is provided on the table cover 60. The chuck table 64 is substantially the same as the above-described chuck table 10, so a detailed description will be omitted. A plurality of (four in this example) clamp units 64b are provided on the outer periphery of the chuck table 64.

[0115] A cantilevered support structure 66 is provided at a position adjacent to the opening 54b. A Y-axis direction moving unit 70 that moves a cutting unit (processing unit) 68 along the Y-axis direction is provided on one surface of the support structure 66.

[0116] The Y-axis direction movement unit 70 has a pair of guide rails 72 that are arranged substantially parallel to the Y-axis direction on one surface of the support structure 66. A Y-axis direction movement table 74 is slidably attached to the pair of guide rails 72.

[0117] A nut portion (not shown) is provided on the back surface of the Y-axis direction moving table 74, and a screw shaft 76 arranged approximately parallel to the Y-axis direction is rotatably connected to this nut portion via multiple balls (not shown).

[0118] A motor (not shown), such as a servo motor or a stepping motor, is connected to one end of the screw shaft 76. When the screw shaft 76 is rotated by the motor, the Y-axis direction moving table 74 moves along the Y-axis direction.

[0119] A Z-axis direction moving unit 78 is provided on the surface of the Y-axis direction moving table 74. The Z-axis direction moving unit 78 has a pair of guide rails 80 arranged substantially parallel to the Z-axis direction. A Z-axis direction moving table 82 is slidably attached to the pair of guide rails 80.

[0120] A nut portion (not shown) is provided on the back surface of the Z-axis direction moving table 82, and a screw shaft 84 arranged approximately parallel to the Z-axis direction is rotatably connected to this nut portion via multiple balls (not shown).

[0121] A motor 86 such as a servo motor or a stepping motor is connected to the upper end of the screw shaft 84. When the motor 86 rotates the screw shaft 84, the Z-axis direction moving table 82 moves along the Z-axis direction.

[0122] A spindle housing 88 that constitutes the cutting unit 68 is fixed to the lower end of the Z-axis direction moving table 82. The spindle housing 88 is a rectangular pillar-shaped case whose longitudinal side is arranged along the Y-axis direction, and a part of a cylindrical spindle (not shown) is rotatably accommodated inside the spindle housing 88.

[0123] A motor (not shown) that rotates the spindle is provided inside the spindle housing 88. The spindle is disposed so that its longitudinal direction is along the Y-axis direction, and the tip of the spindle protrudes from the spindle housing 88 along the Y-axis direction.

[0124] A cutting blade 90 having an annular cutting edge is attached to the tip of the spindle. By rotating the spindle at high speed, the cutting blade 90 rotates at high speed. The lower end of the cutting blade 90 rotating at high speed forms a processing area R where cutting is performed on the workpiece 11. P (not shown in FIG. 8).

[0125] The lower end of the cutting blade 90, which is rotating at high speed, is positioned in the Z-axis direction between the surface 11a of the workpiece 11, which is held by suction on the holding surface 64a of the chuck table 64, and the tape 17, and the cutting unit 68 and the chuck table 64 are moved relatively along the X-axis direction by the X-axis movement unit, thereby cutting the workpiece 11.

[0126] The above-mentioned first imaging unit 38 is provided at a position adjacent to the cutting unit 68 in the +X direction, and the above-mentioned second imaging unit 40 is provided at a position adjacent to the cutting unit 68 in the -X direction.

[0127] That is, the first imaging region R1 captured by the first imaging unit 38 and the second imaging region R2 captured by the second imaging unit 40 are located within the processing region R of the workpiece 11. P 8, the solid-state imaging elements of the first imaging unit 38 and the second imaging unit 40 are not shown.

[0128] The cutting unit 68, the first imaging unit 38, and the second imaging unit 40 are fixed to the Z-axis moving table 82, so that the first imaging unit 38 and the second imaging unit 40, together with the cutting unit 68, move relative to the chuck table 64 by the X-axis moving unit.

[0129] An opening 54c is provided on the opposite side of the opening 54b from the opening 54a in the -Y direction. A spinner cleaning device 92 for cleaning the workpiece 11 after cutting is provided inside the opening 54c.

[0130] An exterior panel (not shown) is provided above the base 54, and the exterior panel located on the side in the +Y direction is provided with a touch panel display 94 that functions as an input device and a display device, similar to the touch panel display 42 described above.

[0131] The operations of the X-axis direction moving unit, the Y-axis direction moving unit 70, the Z-axis direction moving unit 78, the rotational drive source in the support base, the cutting unit 68, the first imaging unit 38, the second imaging unit 40, the clamp unit 64b, etc., as well as whether or not negative pressure is transmitted to the holding surface 64a, are controlled by a controller 96.

[0132] The controller 96 is configured by a computer including, for example, a processor 96a represented by a CPU (Central Processing Unit) and a memory 96b. The memory 96b includes a main storage device such as a DRAM (Dynamic Random Access Memory) and an auxiliary storage device such as a flash memory, a hard disk drive, or a solid state drive.

[0133] The auxiliary storage device stores software including a predetermined program. The processor 96a and other components are operated in accordance with this software to implement the functions of the controller 96. The cutting device 52 of this embodiment can also achieve substantially the same effects as the laser processing device 2 described above.

[0134] That is, by comparing the before-processing image 46A and the after-processing image 46B, it is possible to determine at the cutting device 52 whether or not a defect has occurred in the workpiece 11 due to the cutting process at the cutting device 52. Therefore, the investigation time required to determine whether or not a defect occurring in the workpiece 11 after processing is due to the cutting process at the cutting device 52 can be reduced compared to when the before-processing image 46A obtained by another device and the after-processing image 46B obtained by the cutting device 52 are collected in a predetermined device such as a PC and then the two images are compared.

[0135] Furthermore, compared to capturing an image of the planned division line 13 before processing by the cutting device 52 to obtain a pre-processing image 46A of the workpiece 11, then performing cutting processing on the planned division line 13 of the workpiece 11 by the cutting device 52, and then obtaining a post-processing image 46B of the planned division line 13 after cutting processing, the acquisition of the pre-processing image 46A, cutting processing of the workpiece 11, and obtaining the post-processing image 46B can be achieved in a single operation, so the processing of the workpiece 11 and image acquisition can be carried out efficiently.

[0136] 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.

[0137] In the above-described embodiment, the first imaging unit 38 and the second imaging unit 40 are area sensor cameras (area scan cameras) having solid-state imaging elements 38a, 40a in which a plurality of photoelectric conversion elements are arranged two-dimensionally.

[0138] However, the first imaging unit 38 and the second imaging unit 40 may be line sensor cameras (line scan cameras) having solid-state imaging elements 38a, 40a in which a plurality of photoelectric conversion elements are arranged in a one-dimensional manner.

[0139] In the solid-state imaging element of the line sensor camera, multiple photoelectric conversion elements are arranged over a wider range along the width direction than the length (i.e., the width of the planned division line 13) of the planned division line 13, which is perpendicular to the longitudinal direction (i.e., the direction parallel to the processing feed direction) of the planned division line 13.

[0140] When a line sensor camera is used, the first imaging unit 38 and the second imaging unit 40 rapidly capture images of the workpiece 11 at a predetermined period T (e.g., 1 msec, 0.1 msec, etc.) that is sufficiently shorter than when an area camera is used.

[0141] In other words, when a line sensor camera is used, it is possible to obtain pre-processing images 46A and post-processing images 46B from one end to the other end of all the planned division lines 13 in a more seamless manner than when an area camera is used. Therefore, it is possible to capture changes before and after processing more completely than when an area camera is used.

[0142] Furthermore, when a line sensor camera is used, the controller 44 may set the size of the rectangular area 29 more finely (i.e., the mesh size smaller). By specifying the rectangular area 29, the worker can compare the pre-processing image 46A and the post-processing image 46B at any position on the planned division line 13.

[0143] In the above-described embodiment, the positions of the head portion 36 and the cutting unit 68 in the X-axis direction are fixed, and the chuck tables 10, 64 are moved in the X-axis direction to perform processing feed. Alternatively, the positions of the chuck tables 10, 64 in the X-axis direction may be fixed, and the head portion 36 and the cutting unit 68 may each be moved along the X-axis direction.

[0144] In the above-described embodiment, the chuck tables 10, 64 are arranged so that the holding surfaces 10a, 64a face upward (i.e., in the +Z direction), but the chuck tables 10, 64 may be arranged so that the holding surfaces 10a, 64a face downward (i.e., in the -Z direction). In this case, the workpiece 11 is suction-held by the chuck tables 10, 64 so that the surface 11a is exposed downward.

[0145] In the above-described embodiment, the workpiece unit 21 including the workpiece 11 is held by suction on the holding surfaces 10a, 64a, but the workpiece unit 21 may be held only by the clamp units 10b, 64b (holding units) without suction by negative pressure. [Explanation of symbols]

[0146] 2: Laser processing device (processing device), 4: Base 6: base, 8: wall, 8a: support arm 10: chuck table (holding unit), 10a: holding surface, 10b: clamp unit 11: Workpiece, 11a: Front (one side), 11b: Back side 13: Planned division line, 15: Device, 17: Tape, 19: Annular frame 12: Y-axis direction moving unit, 14: guide rail, 16: Y-axis direction moving table 18: screw shaft, 20: motor 21: Workpiece unit 22: X-axis direction movement unit (processing feed unit) 24: Guide rail, 26: X-axis moving table 23: Defective part, 25, 25a, 25b: Machined groove 27: Chipping, 27a: Protrusion amount, 29: Rectangular area (area), 31: Edge, 33: Width 28: screw shaft, 30: motor, 32: support base 34: Laser beam irradiation unit, 36: Head part 38: First imaging unit, 38a: Solid-state imaging element (first imaging element) 40: second imaging unit, 40a: solid-state imaging element (second imaging element) 42: Touch panel display 44: Controller, 44a: Processor, 44b: Memory 46A: Image before processing, 46B: Image after processing, 46C: Image for analysis 50a: Radio button, 50b: Radio button 52: Cutting device (processing device), 54: Base, 54a, 54b, 54c: Opening 56: Cassette elevator, 58: Cassette 60: table cover, 62: cover member 64: chuck table (holding unit), 64a: holding surface, 64b: clamp unit 66: Support structure, 68: Cutting unit (processing unit) 70: Y-axis direction moving unit, 72: guide rail, 74: Y-axis direction moving table 76: Screw shaft 78: Z-axis direction moving unit, 80: guide rail, 82: Z-axis direction moving table 84: screw shaft, 86: motor 88: Spindle housing, 90: Cutting blade 92: Spinner cleaning device 94: Touch panel display 96: Controller, 96a: Processor, 96b: Memory L: Laser beam L1, L2, L3, L4, L5, L6, L7, L8, L9, L 10 ,L 11 :Travel trajectory R1: first imaging region, R2: second imaging region, R P :Processing area T: period

Claims

1. a holding unit for holding the workpiece; a processing unit that processes the workpiece held by the holding unit; a processing feed unit that moves the holding unit and the processing unit relatively along a processing feed direction; a first imaging unit having a first imaging element and moving together with the processing unit relative to the holding unit by the processing feed unit; a second imaging unit having a second imaging element and moving together with the processing unit and the first imaging unit relative to the holding unit by the processing feed unit; a controller having a processor and a memory, and controlling operations of the processing unit, the processing feed unit, the first imaging unit, and the second imaging unit; Equipped with a first imaging area captured by the first imaging unit is disposed on the opposite side of a second imaging area captured by the second imaging unit in the processing feed direction with a processing area in which processing is performed on the workpiece by the processing unit as the center; When the workpiece is machined while the holding unit and the machining unit are relatively moved along the machining feed direction, the controller one of the first and second imaging units, whose imaging area is located forward in the direction of movement of the processing area, is caused to image a target area including an unprocessed area of ​​the workpiece before processing, thereby obtaining a pre-processing image of the target area; A processing device characterized in that the other of the first imaging unit and the second imaging unit, whose imaging area is located behind the direction of movement of the processing area, is caused to image the target area after processing, thereby obtaining a processed image of the target area.

2. Further comprising a display device for displaying an image, 2. The processing device according to claim 1, wherein the controller causes the display device to display at least one of the pre-processed image and the post-processed image.

3. further comprising an input device for an operator to input instructions to the controller; The processing device described in claim 2, characterized in that when any of a plurality of areas on one surface of the workpiece is selected via the input device, the controller causes both the pre-processing image and the post-processing image of each selected area to be displayed simultaneously on the display device.

4. further comprising an input device for an operator to input instructions to the controller; The processing device described in claim 2, characterized in that the controller does not display the processed image on the display device but displays the pre-processed image in response to a first instruction input via the input device, and does not display the pre-processed image on the display device but displays the processed image in response to a second instruction input via the input device.

5. 5. The processing device according to claim 1, wherein the controller analyzes the results of processing the workpiece in the target area by the processing unit based on the before-processing image and the after-processing image.

Images