Inspection method

Abstract

To provide an inspection method which can suitably inspect whether the orientation of an imaging unit deviates with respect to the X-axis direction of a device.SOLUTION: An inspection method for inspecting the orientation of an imaging unit in a device including a holding table, the imaging unit which images a workpiece 100 held by the holding table, an X-axis direction moving unit which moves the holding table and the imaging unit relatively in the X-axis direction, comprises: a holding table rotation step of rotating the holding table such that a street 102 of the workpiece 100 and the X-axis direction of the imaging unit become in parallel to each other; and a deviation determination step of moving the imaging unit and the holding table relatively in the X-axis direction to image the street 102 after execution of the holding table rotation step and determining that the orientation of the imaging unit 20 deviates in a case where the street 102 moves by a prescribed amount or greater in the Y-axis direction orthogonal to the X-axis direction.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an inspection method for checking whether the orientation of an imaging unit is misaligned with respect to the X-axis direction of a device.

Background Art

[0002] An imaging unit connected to a lens (microscope, objective lens) by screwing or the like so as to be parallel to the X-axis direction of a device such as a processing device for processing a workpiece is used (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, if the screw loosens while the device is operating, the orientation of the imaging unit will shift with respect to the X-axis direction of the device, and the cutting groove (kerf) after the workpiece has been cut will be imaged obliquely, resulting in a problem that the width of the kerf, chipping, etc. cannot be accurately measured.

[0005] The present invention has been made in view of such problems, and an object thereof is to provide an inspection method capable of suitably inspecting whether the orientation of an imaging unit is misaligned with respect to the X-axis direction of a device.

Means for Solving the Problems

[0006] In order to solve the above-described problems and achieve the object, the inspection method of the present invention is an apparatus including a holding table, an imaging unit that images a workpiece held on the holding table, and an X-axis direction moving unit that relatively moves the holding table and the imaging unit in the X-axis direction. The orientation of the imaging unit is the orientation of a reference line set inside the imaging unit, which changes according to the rotation of the imaging unit around the Z-axis.An inspection method for checking the orientation of the imaging unit, comprising: an inspection step of imaging a street formed on a workpiece, or a machined groove or arbitrary pattern formed along the street, and using the acquired image, rotating the holding table so that the street on the workpiece and the X-axis direction of the imaging unit are parallel; and after the holding table rotation step, moving the imaging unit and the holding table relative to each other in the X-axis direction, and imaging the street, or the machined groove or arbitrary pattern formed along the street, and if the street, or the machined groove or pattern formed along the street has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction, then the orientation of the imaging unit is In the X-axis direction The system includes a misalignment detection step that determines that there is a misalignment.

[0007] Furthermore, in order to solve the above-mentioned problems and achieve the objective, the inspection method of the present invention comprises a holding table, an imaging unit for imaging a workpiece held on the holding table, and an X-axis movement unit for moving the holding table and the imaging unit relative to each other in the X-axis direction, The orientation of the imaging unit is the orientation of a reference line set inside the imaging unit, which changes according to the rotation of the imaging unit around the Z-axis. An inspection method for checking the orientation of the imaging unit, comprising: an imaging step of moving the imaging unit and the holding table relative to each other in the X-axis direction to image an arbitrary mark formed on the workpiece in a first imaging area including the mark and a second imaging area including the mark; and a misalignment determination step of determining that the orientation of the imaging unit is misaligned with respect to the X-axis direction if the mark imaged in the second imaging area has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction relative to the mark imaged in the first imaging area. [Effects of the Invention]

[0008] The present invention allows for a suitable inspection of whether the orientation of the imaging unit is misaligned with respect to the X-axis direction of the device. This is achieved by moving the imaging unit and the holding table relatively in the X-axis direction to image a street, and determining if the amount of movement of the street in the Y-axis direction, which is perpendicular to the X-axis direction, is greater than or equal to a predetermined amount set in the storage unit beforehand, or by moving the imaging unit and the holding table relatively in the X-axis direction to image the same mark, and determining if the mark is shifted in the Y-axis direction in the captured image. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a perspective view showing an example of the configuration of a processing apparatus for implementing the inspection method according to Embodiment 1. [Figure 2] Figure 2 is a perspective view showing an example of the configuration of the main parts of the processing apparatus shown in Figure 1. [Figure 3] Figure 3 is an exploded perspective view showing an example of the configuration of the main parts of the processing apparatus shown in Figure 1. [Figure 4] Figure 4 is a flowchart showing the processing procedure of the inspection method according to Embodiment 1. [Figure 5] Figure 5 is a top view illustrating the holding table rotation step in Figure 4. [Figure 6] Figure 6 is a top view illustrating the holding table rotation step in Figure 4. [Figure 7] Figure 7 is a top view illustrating the imaging step and displacement determination step shown in Figure 4. [Figure 8] Figure 8 is a top view illustrating the imaging step and displacement determination step of the inspection method according to Embodiment 2. [Figure 9] Figure 9 is a top view illustrating the imaging step and displacement determination step of the inspection method according to Embodiment 2. [Modes for carrying out the invention]

[0010] Embodiments for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by those skilled in the art, and those that are substantially the same. In addition, the components described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the present invention.

[0011] [Embodiment 1] An inspection method according to Embodiment 1 of the present invention will be described with reference to the drawings. Figure 1 is a perspective view showing an example of the configuration of a processing apparatus 1 that implements the inspection method according to Embodiment 1. Figure 2 is a perspective view showing an example of the configuration of the main parts of the processing apparatus 1 of Figure 1. Figure 3 is an exploded perspective view showing an example of the configuration of the main parts of the processing apparatus 1 of Figure 1. As shown in Figure 1, the processing apparatus 1 includes a holding table 10, an imaging unit 20, a processing unit 40, an X-axis movement unit 51, a Y-axis movement unit 52, a Z-axis movement unit 53, a display unit 60, and a control unit 70.

[0012] The workpiece 100, which is the target of processing by the processing apparatus 1 that implements the inspection method according to Embodiment 1, is, as shown in Figure 1, a disc-shaped semiconductor wafer or optical device wafer made of silicon, sapphire, silicon carbide (SiC), gallium arsenide, glass, etc. as the base material. As shown in Figure 1, the workpiece 100 has chip-sized devices 103 formed in areas demarcated by a plurality of streets (planned division lines) 102 formed in a grid pattern on a flat surface 101. The workpiece 100 may have a characteristic key pattern 110 (see Figures 8 and 9) formed on the surface 101. In Embodiment 1, as shown in Figure 1, an adhesive tape 105 is attached to the back surface 104 of the back side of the surface 101, and an annular frame 106 is attached to the outer edge of the adhesive tape 105, but the present invention is not limited to this. In addition, the workpiece 100 in the present invention may be a rectangular package substrate having a plurality of resin-sealed devices, a ceramic plate, or a glass plate, etc.

[0013] The holding table 10 includes a disk-shaped frame body in which a concave portion is formed, and a disk-shaped suction portion fitted into the concave portion. The suction portion of the holding table 10 is formed of a porous ceramic or the like having a large number of porous holes, and is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown). As shown in FIG. 1, the upper surface of the suction portion of the holding table 10 is a holding surface 11 on which the workpiece 100 is placed and the placed workpiece 100 is sucked and held by the negative pressure introduced from the vacuum suction source. In the first embodiment, the holding surface 11 has the workpiece 100 placed with the surface 101 facing upward, and the placed workpiece 100 is sucked and held from the back surface 104 side via the adhesive tape 105. The holding surface 11 and the upper surface of the frame body of the holding table 10 are arranged on the same plane and are formed parallel to the XY plane, which is a horizontal plane.

[0014] Further, as shown in FIG. 1, the holding table 10 includes clamps 12, which are a plurality (two in the example shown in FIG. 1) of frame holding portions that are arranged on the outer peripheral portion of the frame body and hold and fix a frame 106 adhered to the workpiece 100 via the adhesive tape 105.

[0015] The holding table 10 is provided so as to be movable in the X-axis direction parallel to the horizontal direction by an X-axis direction moving unit 51. By moving in the X-axis direction along with the X-axis direction moving unit 51, the holding table 10 moves the positions of the imaging unit 20 and the processing unit 40 on the surface 101 of the workpiece 100 held by the holding table in the X-axis direction (the direction opposite to the moving direction of the holding table 10). The holding table 10 is provided so as to be rotatable about a Z-axis parallel to the vertical direction and orthogonal to the XY plane by a rotation drive source 15.

[0016] The imaging unit 20 images the workpiece 100 held on the holding table 10. In Embodiment 1, as shown in FIG. 1, the imaging unit 20 is fixed adjacent to the processing unit 40 and, integrally with the processing unit 40, moves relative to the workpiece 100 held on the holding table 10 along the Y-axis direction and the Z-axis direction by the Y-axis direction moving unit 52 and the Z-axis direction moving unit 53, respectively. As shown in FIGS. 2 and 3, the imaging unit 20 includes a microscope unit 21, an imaging unit 22, and a connecting member 23.

[0017] The microscope unit 21 forms an enlarged image of the workpiece 100 held on the holding table 10. As shown in FIGS. 2 and 3, the microscope unit 21 includes a cylindrical lens barrel 24 provided above the holding table 10 so as to face the workpiece 100 held on the holding table 10 in the Z-axis direction, and a rectangular prism-shaped housing 25 provided above the lens barrel 24. The lens barrel 24 is arranged such that its axial direction is along the Z-axis direction. In Embodiment 1, the lens barrel 24 houses, for example, an objective lens inside, and the objective lens forms an enlarged image (workpiece enlarged image) of the workpiece 100 held on the holding table 10.

[0018] The housing 25 has a cavity formed therein that penetrates in the Z-axis direction on the inside. As shown in FIG. 3, an opening 31 and a plurality (three in the example shown in FIG. 3) of screw holes 32 arranged at equal intervals in the circumferential direction along the outer periphery of the opening 31 are formed facing upward. The housing 25 enables the imaging unit 22 to image the workpiece enlarged image formed by the lens barrel 24 from above through the inner cavity. Also, as shown in FIG. 3, the housing 25 receives the insertion of the connecting portion 26 of the imaging unit 22 from the opening 31 through the connecting member 23, and when the connecting member 23 is attached to the screw holes 32, the imaging unit 22 is connected via the connecting member 23 upward.

[0019] The imaging unit 22 captures a magnified image of the workpiece formed by the microscope unit 21. As shown in Figures 2 and 3, the imaging unit 22 has a cylindrical connecting portion 26 and a rectangular prism-shaped housing 27 provided above the connecting portion 26. The connecting portion 26 is positioned so that its axial direction is aligned with the Z-axis direction. The connecting portion 26 has a cavity formed through its interior in the Z-axis direction, which allows the magnified image of the workpiece formed by the microscope unit 21 to be captured from above. Furthermore, as shown in Figure 3, the connecting portion 26 is inserted into the opening 31 of the housing 25 via a connecting member 23, and the connecting member 23 is fitted into a screw hole 32, thereby connecting the microscope unit 21 to the top of the housing 25 via the connecting member 23.

[0020] The housing 27 contains an image sensor that captures a magnified image of the workpiece formed by the microscope unit 21. The image sensor is, for example, a CCD (Charge-Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor. The image sensor inside the housing 27 is electrically connected to the display unit 60 and the control unit 70 via wiring 28, enabling information communication, and outputs the captured magnified image of the workpiece to the display unit 60 and the control unit 70.

[0021] The connecting member 23 has a disc-shaped flange portion 33 and a cylindrical boss portion 34 that protrudes downward from the flange portion 33. The central axes of the flange portion 33 and the boss portion 34 of the connecting member 23 overlap each other, and these central axes are arranged along the Z-axis direction. The connecting member 23 has an insertion hole 35 that penetrates through the flange portion 33 and the boss portion 34 along the Z-axis direction, and the connecting portion 26 of the imaging unit 22 is inserted into and fitted into the inside of the insertion hole 35. The outer diameter of the boss portion 34 is the same as or slightly smaller than the inner diameter of the opening 31 of the housing 25 of the microscope unit 21, and the boss portion 34 is inserted into and fitted into the opening 31 of the housing 25 of the microscope unit 21.

[0022] The flange portion 33 has multiple through holes 36 that penetrate in the Z-axis direction, arranged at equal intervals in the circumferential direction along the outer circumference of the insertion hole 35 at positions corresponding to the screw holes 32 of the housing 25 (three locations in the example shown in Figure 3). The flange portion 33 has multiple screw holes 37 formed on its outer surface that reach the inner insertion hole 35 (two locations in the example shown in Figure 3).

[0023] The connecting member 23 is mounted above the housing 25 of the microscope unit 21 by inserting the boss portion 34 into the opening 31 of the housing 25 of the microscope unit 21 and fitting it together, and then inserting screws 38 into each through hole 36 of the flange portion 33 and screwing them into each screw hole 32 of the housing 25. After the connecting member 23 is mounted above the housing 25 of the microscope unit 21, the connecting portion 26 of the imaging unit 22 is inserted into the insertion hole 35 and fitted together, and then screws 39 are inserted into each screw hole 37 of the flange portion 33 and tightened, thereby connecting the imaging unit 22 and the microscope unit 21 and fixing them so that they do not rotate relative to each other around the Z axis.

[0024] The connecting member 23 allows for adjustment of the relative positional relationship between the imaging unit 22 and the microscope unit 21 in the rotational direction of the Z axis by loosening all the screws 39, rotating the imaging unit 22 and the microscope unit 21 relative to each other around the Z axis, and then tightening all the screws 39 again. This allows for adjustment of the orientation of the imaging unit 20. Here, the orientation of the imaging unit 20 is the orientation of the reference line 29 of the imaging unit 20 (see Figure 2), that is, the orientation of the reference line set inside the imaging unit 20, specifically the orientation of the image sensor inside the housing 27, and it rotates in accordance with the rotation of the imaging unit 22 relative to the microscope unit 21 around the Z axis. In Embodiment 1, the orientation of the imaging unit 20 is adjusted to be parallel to the X axis.

[0025] The imaging unit 20 captures an image of the magnified workpiece formed by the microscope unit 21 using the imaging unit 22, obtains an image of the magnified workpiece, associates the obtained image with information on the orientation of the reference line 29 of the imaging unit 20, and outputs it to the display unit 60 and the control unit 70. The imaging unit 20 captures images for performing the holding table rotation step 1001 (see Figure 4) of the inspection method according to Embodiment 1 described later, and images for performing the misalignment determination step 1003 (see Figure 4) of the inspection method according to Embodiment 1. The imaging unit 20 also captures images for performing alignment to position the workpiece 100 and the processing unit 40, and images for performing a processing check to automatically confirm whether the processing on the workpiece 100 was performed within a normal range. The processing check is, for example, a kerf check to check the processing grooves formed by cutting or laser processing. Here, kerf check is the process of detecting the machined groove based on images taken of the groove, and detecting the width of the groove, the chipping associated with the groove, the meandering of the groove, and the discrepancy between the position of the groove and the position to be machined.

[0026] As shown in Figure 1, the machining unit 40 is a cutting unit that has a spindle with a cutting blade attached to its tip and cuts the workpiece 100 held on the holding table 10. The machining unit 40 has a cutting blade attached to the tip of the spindle that rotates around an axis parallel to one horizontal direction (the Y-axis direction in Figure 1) due to the rotational movement of the spindle, and cuts the workpiece 100 held on the holding table 10 along a street 102 oriented parallel to the X-axis direction.

[0027] The machining unit 40 is provided with a Y-axis movement unit 52 so as to be movable in the Y-axis direction, which is parallel to the horizontal direction and perpendicular to the X-axis direction, and a Z-axis movement unit 53 so as to be movable in the Z-axis direction. The machining unit 40 moves relative to the workpiece 100 held on the holding table 10 along the Y-axis direction and the Z-axis direction, respectively, by the Y-axis movement unit 52 and the Z-axis movement unit 53.

[0028] The processing unit 40 is not limited to this in the present invention, and may also be a laser processing unit that irradiates one side of the workpiece 100 held on the holding table 10 with a laser beam and laser processes the workpiece 100 along a street 102 oriented parallel to the X-axis direction with the laser beam.

[0029] The X-axis movement unit 51, the Y-axis movement unit 52, and the Z-axis movement unit 53 move the holding table 10, the imaging unit 20, and the processing unit 40 relative to each other in the X-axis, Y-axis, and Z-axis directions, respectively. In Embodiment 1, the X-axis movement unit 51 moves the holding table 10 relative to the imaging unit 20 and the processing unit 40 along the X-axis direction. In Embodiment 1, the Y-axis movement unit 52 and the Z-axis movement unit 53 move the imaging unit 20 and the processing unit 40 relative to the holding table 10 along the Y-axis and Z-axis directions, respectively. The X-axis movement unit 51, the Y-axis movement unit 52, and the Z-axis movement unit 53 are each configured to include, for example, a well-known ball screw rotatably mounted around the axes of the X, Y, and Z axes, a well-known pulse motor for rotating the ball screw around its axis, and a well-known guide rail for supporting the holding table 10 or the imaging unit 20 and processing unit 40 so that they can move in the X-axis, Y-axis, or Z-axis direction.

[0030] The X-axis movement unit 51, the Y-axis movement unit 52, and the Z-axis movement unit 53 include encoders that read the rotational position of pulse motors. Based on the rotational position of pulse motors read by the encoders, they detect the relative positions of the holding table 10, the imaging unit 20, and the processing unit 40 in the X-axis, Y-axis, and Z-axis directions, and output the detected relative positions to the control unit 70. Here, the relative positions in the X-axis, Y-axis, and Z-axis directions are determined using the device's Cartesian coordinate system (XYZ coordinates) installed in the processing device 1. For example, the origin of the device's Cartesian coordinate system is set to the center of the holding surface 11 of the holding table 10. Furthermore, the X-axis movement unit 51, Y-axis movement unit 52, and Z-axis movement unit 53 are not limited to a configuration in which encoders detect the relative positions of the holding table 10, the imaging unit 20, and the processing unit 40. They may also be configured with linear scales parallel to the X-axis, Y-axis, and Z-axis directions, and reading heads that are movable in the X-axis, Y-axis, and Z-axis directions by the X-axis movement unit 51, Y-axis movement unit 52, and Z-axis movement unit 53, respectively, and read the markings on the linear scales.

[0031] The display unit 60 is mounted on a cover (not shown) of the processing device 1, with its display surface facing outwards. The display unit 60 displays to the operator, in a visible manner, the processing conditions of the processing device 1, the imaging conditions of the imaging unit 20, various conditions for performing the inspection method according to Embodiment 1, the screen for setting various conditions such as alignment and processing checks, images captured by the imaging unit 20 for performing the inspection method according to Embodiment 1, images for performing alignment and processing checks, the judgment results when performing the inspection method according to Embodiment 1, and the confirmation results from processing checks. The display unit 60 is composed of a liquid crystal display device or the like. The display unit 60 is equipped with an input unit (not shown) that the operator uses to input information regarding the various conditions of the processing device 1 and information regarding the display of images. The input unit provided on the display unit 60 is composed of at least one of a touch panel provided on the display unit 60 and a keyboard or the like. Note that the display unit 60 is not fixed to the processing device 1, but can be provided on any communication device, and any communication device may be connected to the processing device 1 wirelessly or wired.

[0032] In Embodiment 1, the display unit 60 displays the reference line 29 of the imaging unit 20 in the image to be displayed. The reference line 29 of the imaging unit 20 is set by the control unit 70 to be parallel to the horizontal direction of the display unit 60's screen. By displaying the reference line 29 of the imaging unit 20, the display unit 60 can visually display to the operator the relationship between the reference line 29 of the imaging unit 20 and the street 102 in the image of the workpiece 100 to be displayed, for example, as shown in Figure 2.

[0033] The processing apparatus 1 is equipped with a notification unit (not shown). The notification unit is, for example, located above a cover (not shown) of the processing apparatus 1. In Embodiment 1, the notification unit is, for example, a light-emitting unit composed of light-emitting diodes, or a sound unit composed of a speaker, which emits sound. The light-emitting unit, as a notification unit, notifies the operator of errors that occur during imaging by the imaging unit 20 or during processing by the processing unit 40, or the results of confirmation by processing checks, through the illumination, flashing, or color of the light-emitting unit. The sound unit, as a notification unit, notifies the operator of errors that occur or the results of confirmation by processing checks, etc., through the sound of the sound unit. The notification unit is not fixed to the processing apparatus 1, but can be provided in any communication device, and any communication device may be connected to the processing apparatus 1 wirelessly or by wire.

[0034] The control unit 70 controls the operation of each component of the processing apparatus 1 to cause the processing apparatus 1 to perform various processes on the workpiece 100, including the inspection method according to Embodiment 1. The control unit 70 includes a storage unit 71. The storage unit 71 stores information such as a predetermined amount and a predetermined angle, which are criteria for determining whether the street 102 has moved by a predetermined amount or more in the displacement determination step 1003 described later, and whether it is tilted by a predetermined angle or more with respect to the reference line 29 of the imaging unit 20; various images captured by the imaging unit 20; information about the street 102 of the workpiece 100 (such as the number of street 102s and the X and Y coordinates representing the position of each street 102 in the workpiece 100); information about the characteristic key pattern 110 of the workpiece 100 (for example, a reference image of the characteristic key pattern 110); XY coordinate information representing the position of the characteristic key pattern 110 in the workpiece 100; and processing information related to the processing of the workpiece 100. The processing information related to the processing of workpiece 100 includes processing conditions that are set in advance before processing workpiece 100 and referenced when processing workpiece 100, and processing data detected by any detectors provided on each component of the processing apparatus 1 during and after processing workpiece 100.

[0035] In Embodiment 1, the control unit 70 includes a computer system. The computer system included in the control unit 70 has an arithmetic processing unit having a microprocessor such as a CPU (Central Processing Unit), a storage device having memory such as ROM (Read Only Memory) or RAM (Random Access Memory), and an input / output interface device. The arithmetic processing unit of the control unit 70 performs arithmetic processing according to a computer program stored in the storage device of the control unit 70 and outputs control signals for controlling the processing device 1 to each component of the processing device 1 via the input / output interface device of the control unit 70. In Embodiment 1, the function of the storage unit 71 is realized by the storage device of the control unit 70.

[0036] Figure 4 is a flowchart showing the processing procedure of the inspection method according to Embodiment 1. The inspection method according to Embodiment 1 is an example of the operation process performed by the processing apparatus 1, and as shown in Figure 4, comprises a holding table rotation step 1001, an imaging step 1002, and a displacement determination step 1003.

[0037] In the inspection method according to Embodiment 1, the control unit 70 transports the workpiece 100 onto the holding table 10 using a transport unit (not shown) or the like before performing the holding table rotation step 1001, and the holding table 10 holds the workpiece 100 on the holding surface 11.

[0038] The holding table rotation step 1001 involves imaging the street 102 formed on the workpiece 100, and using the captured images 301, 302 (see Figures 5 and 6), rotating the holding table 10 so that the street 102 of the workpiece 100 is parallel to the X-axis direction of the processing device 1 and the imaging unit 20. In Embodiment 1, the holding table rotation step 1001 involves imaging the street 102, but the present invention is not limited to this. Alternatively, the holding table rotation step 1001 may involve imaging a processing groove formed along the street 102 by cutting or laser processing, or any pattern formed in the device area (for example, a characteristic key pattern 110), and using the captured image, the holding table 10 may be rotated so that the street 102 of the workpiece 100 is parallel to the X-axis direction of the processing device 1 and the imaging unit 20.

[0039] Figures 5 and 6 are top views illustrating the holding table rotation step 1001 of Figure 4. In the holding table rotation step 1001, as shown in Figures 5 and 6, the control unit 70 first aligns the imaging area of ​​the imaging unit 20 with a region 201 on the surface 101 of the workpiece 100 that includes an arbitrary street 102, and images the region 201 to obtain an image 301. Next, the imaging area of ​​the imaging unit 20 aligns with a region 202 that includes a street 102 that is different from region 201, and images the region 202 to obtain an image 302. In the holding table rotation step 1001, the control unit 70 moves the imaging unit 20 relative to the workpiece 100 held on the holding table 10 using the X-axis movement unit 51, the Y-axis movement unit 52, and the Z-axis movement unit 53, thereby aligning the imaging area of ​​the imaging unit 20 with each region 201, 202.

[0040] In the holding table rotation step 1001, the control unit 70 calculates the XY coordinates of the centers of regions 201 and 202, the XY coordinates of the center of street 102 in image 301 of region 201, and the XY coordinates of the center of the same street 102 in image 302 of region 202, and calculates the inclination angle of street 102 with respect to the X-axis direction in which it extends from the difference between these two XY coordinates of the centers of street 102. In the holding table rotation step 1001, the control unit 70 rotates the holding table 10 that holds the workpiece 100 with the rotation drive source 15 in a direction 17 (see Figure 6) that eliminates this inclination angle to 0, based on the calculated inclination angle of street 102 with respect to the X-axis direction in which it extends.

[0041] In the holding table rotation step 1001, if the direction in which the street 102 extends is inclined with respect to the X-axis direction, as shown in Figure 5, the control unit 70 rotates the holding table 10 to eliminate the inclination angle. When the holding table 10 is rotated to eliminate the inclination angle, the direction in which the street 102 extends becomes not inclined with respect to the X-axis direction, as shown in Figure 6. On the other hand, in the holding table rotation step 1001, if the direction in which the street 102 extends is not inclined with respect to the X-axis direction, as shown in Figure 6, the control unit 70 does not need to rotate the holding table 10.

[0042] Although the inspection method according to Embodiment 1 includes the holding table rotation step 1001, the present invention is not limited thereto, and the holding table rotation step 1001 may be omitted.

[0043] In Embodiment 1, the imaging step 1002 is a step in which the imaging unit 20 and the holding table 10 are moved relative to each other in the X-axis direction to image any street 102 of the workpiece 100 held on the holding table 10. In Embodiment 1, the imaging step 1002 images the street 102, but the present invention is not limited to this, and processing grooves formed along the street 102 by cutting or laser processing, or patterns formed in the device area may also be imaged.

[0044] Figure 7 is a top view illustrating the imaging step 1002 and displacement determination step 1003 of Figure 4. In the imaging step 1002, the control unit 70 moves the imaging unit 20 in the Y-axis direction and Z-axis direction relative to the workpiece 100 held on the holding table 10 using the Y-axis direction movement unit 52 and the Z-axis direction movement unit 53, thereby aligning the imaging area of ​​the imaging unit 20 with any street 102 on the surface 101 of the workpiece 100. The imaging unit 70 then moves the imaging unit 20 in the X-axis direction relative to the workpiece 100 held on the holding table 10 using the X-axis direction movement unit 51, thereby aligning the imaging area of ​​the imaging unit 20 with one or more areas including the street 102, and the imaging unit 20 images the imaging area to obtain one or more images.

[0045] In the imaging step 1002, the control unit 70, as shown in Figure 7, images the first region 211, the second region 212, and the third region 213, which include the street 102 imaged in the holding table rotation step 1001, and acquires images 311, 312, and 313, respectively. The first region 211 is the region on the workpiece 100 corresponding to the region 201 mentioned above, the second region 212 is the region on the workpiece 100 corresponding to the region 202 mentioned above, and the third region 213 is the region intermediate between the first region 211 and the second region 212.

[0046] In Embodiment 1, the displacement determination step 1003 is a step in which, if the street 102 captured in the imaging step 1002 has moved by a predetermined amount set in the storage unit 71 in the Y-axis direction which is perpendicular to the X-axis direction, the orientation of the imaging unit 20 is determined to be shifted with respect to the X-axis direction.

[0047] If the orientation of the imaging unit 20 is shifted with respect to the X-axis direction, in the imaging step 1002, the imaging unit 20 is moved in the X-axis direction relative to the workpiece 100 held on the holding table 10, and the street 102, which is oriented parallel to the X-axis direction, is imaged. As a result, the street 102 is tilted with respect to the reference line 29 of the imaging unit 20 by the amount of the shift, and the image is obtained by moving the imaging area along the street 102. Therefore, for any images 311, 312, 313 captured in the imaging step 1002, the amount of movement 315, 316, 317, which is the amount that the street 102 moves in the Y-axis direction perpendicular to the X-axis direction, can be calculated to quantitatively determine the shift in the orientation of the imaging unit 20 with respect to the X-axis direction.

[0048] In the displacement determination step 1003, as shown in Figure 7, the control unit 70 calculates the amount of movement 315, 316, and 317 of the street 102 in the Y-axis direction perpendicular to the X-axis direction for any images 311, 312, and 313 captured in the imaging step 1002. If the amount of movement 315, 316, and 317 is less than a predetermined amount set in the storage unit 71 beforehand, it is determined that the orientation of the imaging unit 20 is not shifted with respect to the X-axis direction. If the amount of movement 315, 316, and 317 is greater than or equal to a predetermined amount set in the storage unit 71 beforehand, it is determined that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction.

[0049] In the displacement determination step 1003, as shown in Figure 7, the control unit 70 calculates the amount of movement 315, 316, and 317 of the street 102 in the Y-axis direction perpendicular to the X-axis direction for any images 311, 312, and 313 captured in the imaging step 1002. If the amount of movement 315, 316, and 317 is less than a predetermined amount set in the storage unit 71 beforehand, it is determined that the orientation of the imaging unit 20 is not shifted with respect to the X-axis direction. If the amount of movement 315, 316, and 317 is greater than or equal to a predetermined amount set in the storage unit 71 beforehand, it is determined that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction.

[0050] In Embodiment 1, the displacement determination step 1003 is performed by determining whether the street 102 captured in the imaging step 1002 has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction, as set in the storage unit 71 beforehand. However, the present invention is not limited to this, and instead, if the inclination θ1 of the imaging unit 20 with respect to the reference line 29 of the street 102 captured in the imaging step 1002 is greater than or equal to a predetermined angle set in the storage unit 71 beforehand, it may be determined that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction.

[0051] Furthermore, by calculating the inclination θ1 of the imaging unit 20 on street 102 with respect to the reference line 29 for any images 311, 312, and 313 captured in imaging step 1002, the deviation of the orientation of the imaging unit 20 with respect to the X-axis can be quantitatively determined.

[0052] In the displacement determination step 1003, as shown in Figure 7, the control unit 70 calculates the inclination θ1 of the imaging unit 20 of street 102 with respect to the reference line 29 for any images 311, 312, 313 captured in the imaging step 1002. If the inclination θ1 is less than a predetermined angle set in the storage unit 71 beforehand, it is determined that the orientation of the imaging unit 20 is not shifted with respect to the X-axis direction. If the inclination θ1 is greater than or equal to a predetermined angle set in the storage unit 71 beforehand, it is determined that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction.

[0053] If the control unit 70 determines in the misalignment detection step 1003 that the orientation of the imaging unit 20 is misaligned with respect to the X-axis direction, it notifies an error. The control unit 70 displays an image on the display unit 60 in a manner recognizable to the operator indicating that the orientation of the imaging unit 20 was determined to be misaligned with respect to the X-axis direction in the misalignment detection step 1003, and the notification unit notifies the operator in a manner recognizable to that the orientation of the imaging unit 20 was determined to be misaligned with respect to the X-axis direction in the misalignment detection step 1003, prompting the operator to adjust the relative positional relationship of the imaging unit 22 and the microscope unit 21 in the rotational direction around the Z-axis by performing actions such as tightening the screw 39. The control unit 70 may also transmit a message to the display unit 60 or notification unit connected via any communication device indicating that the orientation of the imaging unit 20 was determined to be misaligned with respect to the X-axis direction in the misalignment detection step 1003.

[0054] If the control unit 70 determines in the displacement determination step 1003 that the orientation of the imaging unit 20 is not shifted with respect to the X-axis direction, it displays an image to that effect on the display unit 60 in a way that can be recognized by the operator.

[0055] Furthermore, if the control unit 70 determines in the displacement determination step 1003 that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction, it generates image data by rotating the image acquired by the imaging unit 20 for machining checks (kerf checks) by an angle equivalent to the movement amounts 315, 316, and 317 (by the amount of the inclination θ1), displays it on the display unit 60, and measures the width of the machining groove, etc., using the rotated image data.

[0056] The inspection method according to Embodiment 1, having the configuration described above, involves moving the imaging unit 20 and the holding table 10 relative to each other in the X-axis direction to image the street 102. If the amount of movement 315, 316, 317 of the street 102 in the Y-axis direction perpendicular to the X-axis direction is greater than or equal to a predetermined amount set in the storage unit 71 beforehand, or if the street 102 is tilted at a predetermined angle or more with respect to the reference line 29 of the imaging unit 20, it is determined that the orientation of the imaging unit 20 is misaligned. This method provides the advantage of being able to suitably check whether the orientation of the imaging unit 20 is misaligned with respect to the X-axis direction of the device.

[0057] [Embodiment 2] The inspection method according to Embodiment 2 of the present invention will be described with reference to the drawings. Figures 8 and 9 are top views illustrating the imaging step 1002 and the displacement determination step 1003 of the inspection method according to Embodiment 2. In Figures 8 and 9, the same reference numerals are used for the same parts as in the embodiment, and their descriptions are omitted.

[0058] The inspection method according to Embodiment 2 is the same as in Embodiment 1, except that the imaging step 1002 and the displacement determination step 1003 are modified, and the other configurations are the same as in Embodiment 1.

[0059] The imaging step 1002 of the inspection method according to Embodiment 2 is a step in which any identical mark formed on the workpiece 100 is imaged by moving the imaging unit 20 and the holding table 10 relative to each other in the X-axis direction, at a position where the imaging area of ​​the imaging unit 20 becomes the first imaging area 221 and at a position where the imaging area of ​​the imaging unit 20 becomes the second imaging area 222, as shown in Figures 8 and 9.

[0060] In the imaging step 1002 of Embodiment 2, the arbitrary mark is a characteristic key pattern 110 formed on the surface 101, as shown in Figures 8 and 9. However, the present invention is not limited to this, and may also be a characteristic trace of a processed groove formed along the street 102 by cutting, laser processing, or the like.

[0061] In the imaging step 1002 of Embodiment 2, the control unit 70 moves the imaging unit 20 in the X-axis direction, Y-axis direction, and Z-axis direction relative to the workpiece 100 held on the holding table 10 using the X-axis direction movement unit 51, the Y-axis direction movement unit 52, and the Z-axis direction movement unit 53, thereby aligning the imaging area of ​​the imaging unit 20 with a first imaging area 221 that includes an arbitrary mark (key pattern 110) on the surface 101 of the workpiece 100, and the imaging unit 20 images the first imaging area 221 to acquire an image 321. The X-axis direction movement unit 51 moves the imaging unit 20 in the X-axis direction relative to the workpiece 100 held on the holding table 10, aligning the imaging area of ​​the imaging unit 20 with a second imaging area 222 that is different from the first imaging area 221 that includes the same mark (key pattern 110), and the imaging unit 20 images the second imaging area 222 to acquire an image 322.

[0062] The displacement determination step 1003 of the inspection method according to Embodiment 2 is a step in which, if a mark captured in the second imaging area 222 has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction relative to a mark captured in the first imaging area 221, it is determined that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction.

[0063] If the orientation of the imaging unit 20 is shifted with respect to the X-axis direction, then in the imaging step 1002, when the imaging unit 20 is moved in the X-axis direction relative to the workpiece 100 held on the holding table 10 to image the key pattern 110, an image is obtained in which the key pattern 110 has moved in the Y-axis direction as the imaging area moves in the X-axis direction, according to the inclination of the street 102 with respect to the reference line 29 of the imaging unit 20, that is, according to the amount of the shift. For this reason, by calculating the amount of Y-axis movement 325 (see Figure 8) of the key pattern 110 for the images 321 and 322 captured in the imaging step 1002 of Embodiment 2, the shift in the orientation of the imaging unit 20 with respect to the X-axis direction can be quantitatively determined in effect.

[0064] In the displacement determination step 1003 of Embodiment 2, as shown in Figures 8 and 9, the control unit 70 calculates the amount of movement 325 of the key pattern 110 in the Y-axis direction relative to the amount of movement 326 in the X-axis direction of the imaging region for the images 321 and 322 captured in the imaging step 1002 of Embodiment 2. In the displacement determination step 1003 of Embodiment 2, as shown in Figure 9, the control unit 70 determines that the orientation of the imaging unit 20 is not shifted in the X-axis direction if this amount of movement 325 is less than a predetermined amount set in the storage unit 71 beforehand, and determines that the orientation of the imaging unit 20 is shifted in the X-axis direction if this amount of movement 325 is greater than or equal to a predetermined amount set in the storage unit 71 beforehand, as shown in Figure 8.

[0065] Furthermore, by calculating the Y-axis movement 325 of the key pattern 110 relative to the X-axis movement 326 of the imaging region for the images 321 and 322 captured in the imaging step 1002 of Embodiment 2, the inclination of the imaging unit 20 with respect to the reference line 29 in the X-axis direction can be calculated, and this also allows for the quantitative determination of the deviation of the orientation of the imaging unit 20 with respect to the X-axis direction.

[0066] In the inspection method according to Embodiment 2, the deviation determination step 1003 is determined by whether the mark captured in the second imaging area 222 has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction relative to the mark captured in the first imaging area 221. However, the present invention is not limited to this, and instead, if the mark captured in the second imaging area 222 is tilted by a predetermined angle or more relative to the mark captured in the first imaging area 221, it may be determined that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction. Here, the tilt of the mark captured in the second imaging area 222 relative to the mark captured in the first imaging area 221 represents the amount of movement of the mark in the Y-axis direction 325 relative to the amount of movement of the imaging area in the X-axis direction 326, that is, the value obtained by dividing the amount of movement of the mark in the Y-axis direction 325 by the amount of movement of the imaging area in the X-axis direction 326.

[0067] In this case, in the displacement determination step 1003 of Embodiment 2, as shown in Figures 8 and 9, the control unit 70 calculates the amount of movement 325 of the key pattern 110 in the Y-axis direction relative to the amount of movement 326 in the X-axis direction of the imaging area for the images 321 and 322 captured in the imaging step 1002 of Embodiment 2, and calculates the inclination of the imaging unit 20 of the device with respect to the reference line 29 in the X-axis direction based on this. In the displacement determination step 1003 of Embodiment 2, as shown in Figure 9, the control unit 70 determines that the orientation of the imaging unit 20 is not shifted with respect to the X-axis direction if this inclination is less than a predetermined angle set in the storage unit 71 beforehand, and determines that the orientation of the imaging unit 20 is shifted with respect to the X-axis direction if this inclination is greater than or equal to a predetermined angle set in the storage unit 71 beforehand, as shown in Figure 8.

[0068] The inspection method according to Embodiment 2, having the configuration described above, involves moving the imaging unit 20 and the holding table 10 relative to each other in the X-axis direction to image the same mark (key pattern 110), and determining that the orientation of the imaging unit 20 is misaligned if the mark (key pattern 110) in the image is shifted in the Y-axis direction. This method effectively allows for checking whether the orientation of the imaging unit 20 is misaligned with respect to the X-axis direction of the apparatus.

[0069] It should be noted that the present invention is not limited to the embodiments described above. That is, it can be implemented with various modifications without departing from the core principles of the present invention. [Explanation of symbols]

[0070] 1 Processing equipment 10 Retention Table 20 Imaging Unit 29. Reference Line 51 X-axis movement unit 100 Work 102 Street 110 Key Patterns 211 First area 212 Second area 213 Third area 221 First imaging area 222 Second imaging area Images 301, 302, 311, 312, 313, 321, 322 315, 316, 317, 325, 326 Displacement

Claims

1. The holding table and An imaging unit for imaging a workpiece held on the holding table, In a device comprising a holding table, an imaging unit, and an X-axis movement unit for moving them relative to each other in the X-axis direction, The orientation of the imaging unit is the orientation of a reference line set inside the imaging unit, which changes according to the rotation of the imaging unit around the Z-axis. An inspection method for checking the orientation of the imaging unit, A holding table rotation step involves imaging a street formed on a workpiece, or a machined groove or any pattern formed along said street, and using the captured image, rotating the holding table so that the street on the workpiece and the X-axis direction of the imaging unit are parallel. After the holding table rotation step is performed, the imaging unit and the holding table are moved relative to each other in the X-axis direction to image the street, or a machined groove or any pattern formed along the street, and if the street, or the machined groove or pattern formed along the street has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction, the orientation of the imaging unit is determined to be shifted with respect to the X-axis direction (a shift determination step). An inspection method that includes the following features.

2. The holding table and An imaging unit for imaging a workpiece held on the holding table, In a device comprising a holding table, an imaging unit, and an X-axis movement unit for moving them relative to each other in the X-axis direction, The orientation of the imaging unit is the orientation of a reference line set inside the imaging unit, which changes according to the rotation of the imaging unit around the Z-axis. An inspection method for checking the orientation of the imaging unit, An imaging step in which an arbitrary mark formed on the workpiece is imaged by moving the imaging unit and the holding table relative to each other in the X-axis direction, thereby imaging the mark in a first imaging region including the mark and a second imaging region including the mark. A displacement determination step is performed to determine that the orientation of the imaging unit is shifted with respect to the X-axis direction if, with respect to the mark captured in the first imaging area, the mark captured in the second imaging area has moved by a predetermined amount or more in the Y-axis direction perpendicular to the X-axis direction, and An inspection method that includes the following features.

Images