Processing device

Abstract

Provided is a machining device capable of accurately measuring the shape of a machined workpiece. The processing apparatus includes: a table that holds a workpiece on a holding surface orthogonal to a Z axis; a processing unit that processes the workpiece on the table; an imaging unit that images the surface of the workpiece in a light interference manner; a drive unit that moves the imaging unit relative to the table in the Z-axis direction; and an imaging control unit that controls the drive unit and the imaging unit to scan and image the surface of the workpiece on the table in the Z-axis direction. When scanning and imaging the surface of the workpiece in the Z-axis direction, the imaging control unit performs imaging in accordance with imaging conditions determined for each imaged site.

Description

Technical Field

[0001] The present invention relates to a processing apparatus, and more particularly to a processing apparatus including an imaging unit that performs imaging by optical interference. Background Art

[0002] As a processing apparatus that uses a blade (ultra-thin outer peripheral edge) attached to a high-speed rotating spindle to perform cutting processing on a workpiece, a cutting apparatus (blade cutter) is known. In Patent Document 1, a cutting apparatus including a white interferometer inside the apparatus is described. According to the cutting apparatus described in Patent Document 1, the shape of a cutting groove (cut) can be measured inside the apparatus using the white interferometer.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-084201 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In a shape measurement apparatus using an optical interference method such as a white interferometer, measurement is performed by capturing a so-called interference image. The light irradiated from a light source is split into two, one is irradiated onto a reference surface, the other is irradiated onto the surface of an object to be measured, and a reflected light from both is received by an image sensor to capture an interference image.

[0008] When measuring a groove using a shape measurement apparatus using an optical interference method, there are cases where the reflected light from the inside of the groove becomes weak, the S / N ratio becomes small, and noise misidentification occurs. In addition, when measuring a groove using a shape measurement apparatus using an optical interference method, there are cases where false interference fringes are generated due to the reflected light inside the groove. These false interference fringes become unstable factors and false detection factors when extracting the original shape.

[0009] The present invention has been made in view of such circumstances, and an object thereof is to provide a processing apparatus capable of accurately measuring the shape of a processed workpiece.

[0010] Means for Solving the Problems

[0011] To solve the above problems, the processing apparatus according to the first aspect includes: a worktable that holds a workpiece on a holding surface orthogonal to the Z-axis; a processing unit that processes the workpiece on the worktable; an imaging unit that images the surface of the workpiece by optical interference; a driving unit that relatively moves the imaging unit relative to the worktable in the direction of the Z-axis; and an imaging control unit that controls the driving unit and the imaging unit, scans and images the surface of the workpiece on the worktable in the direction of the Z-axis, and the imaging control unit images according to the imaging conditions determined for each imaged part when scanning and imaging the surface of the workpiece in the direction of the Z-axis.

[0012] On the basis of the processing apparatus according to the first aspect, in the processing apparatus according to the second aspect, the imaging control unit irradiates illumination light with a light amount determined for each part and images the surface of the workpiece.

[0013] On the basis of the processing apparatus according to the first aspect, in the processing apparatus according to the third aspect, the imaging control unit performs gain adjustment with a setting determined for each part and images the surface of the workpiece.

[0014] On the basis of the processing apparatus according to the first aspect, in the processing apparatus according to the fourth aspect, the imaging control unit controls the exposure time with a setting determined for each part and images the surface of the workpiece.

[0015] On the basis of the processing apparatus according to the first aspect, in the processing apparatus according to the fifth aspect, the imaging control unit performs grayscale correction with a setting determined for each part and images the surface of the workpiece.

[0016] On the basis of the processing apparatus according to the first aspect, in the processing apparatus according to the sixth aspect, the imaging control unit outputs pixel values from each pixel within an output range determined for each part and images the surface of the workpiece.

[0017] On the basis of the processing apparatus according to the first aspect, in the processing apparatus according to the seventh aspect, when imaging a groove formed on the surface of the workpiece, it is divided into a first part including the surface of the workpiece, a third part including the bottom surface of the groove, and a second part between the first part and the third part, and imaging conditions are determined for each divided part.

[0018] On the basis of the processing apparatus according to the first aspect, the processing apparatus according to the eighth aspect further includes an image processing unit that processes the image obtained by scanning and imaging the surface of the workpiece in the direction of the Z-axis to measure the shape of the surface of the workpiece.

[0019] On the basis of the processing apparatus according to any one of the first to eighth aspects, the processing apparatus according to the ninth aspect further includes: a workpiece information acquisition unit that acquires workpiece information including information on the shape of a cross-section of the workpiece; and a imaging condition setting unit that sets imaging conditions based on the workpiece information.

[0020] The processing apparatus according to the tenth aspect further includes an output range setting unit that sets the output range of an image based on the information on the shape of the cross section of the workpiece, and the shooting control unit extracts and outputs an image of the range set by the output range setting unit from the captured image.

[0021] The processing apparatus according to the eleventh aspect further includes an output range setting unit that analyzes the captured image to set the output range, and the shooting control unit extracts and outputs an image of the range set by the output range setting unit from the captured image, based on the processing apparatus according to any one of the first to eighth aspects.

[0022] The processing apparatus according to the twelfth aspect, based on the processing apparatus according to the eleventh aspect, the output range setting unit analyzes the captured image to identify the interface of the workpiece, and sets the identified interface and a specified range as the output range.

[0023] The processing apparatus according to the thirteenth aspect, based on the processing apparatus according to the twelfth aspect, when shooting a groove formed on the surface of the workpiece, the output range setting unit identifies the surface of the workpiece, the inner wall surface of the groove, and the bottom surface of the groove, and sets a specified range including the identified surfaces as the output range.

[0024] The processing apparatus according to the fourteenth aspect, based on the processing apparatus according to any one of the first to eighth aspects, the imaging unit images the surface of the workpiece by white light interference.

[0025] Advantages of the Invention

[0026] According to the present invention, the shape of the machined workpiece can be measured with good accuracy. Brief Description of the Drawings

[0027] Figure 1 is a front view showing an embodiment of a cutting apparatus to which the present invention is applied.

[0028] Figure 2 is a diagram showing a schematic structure of a worktable.

[0029] Figure 3 is a diagram showing a schematic structure of a first imaging unit.

[0030] Figure 4 is a diagram showing a schematic structure of a second imaging unit.

[0031] Figure 5 is a block diagram of a control system of the cutting apparatus.

[0032] Figure 6 is a block diagram of functions of an image processing unit.

[0033] Figure 7 is a block diagram of an electrical structure of the first imaging unit.

[0034] Figure 8 It is a block diagram of the electrical structure of the second imaging unit.

[0035] Figure 9 It is a conceptual diagram of the light quantity control of illumination light.

[0036] Figure 10 It is a block diagram of the functions of the second camera control unit related to the control of the light quantity of illumination light.

[0037] Figure 11 It is a flowchart showing the sequence of processes for measuring the shape of a grooved part.

[0038] Figure 12 It is a flowchart showing the sequence of processes for capturing an interference image.

[0039] Figure 13 It is a block diagram of the functions of the second camera control unit related to the control of gain.

[0040] Figure 14 It is a flowchart showing the sequence of processes for capturing an interference image.

[0041] Figure 15 It is a block diagram of the functions of the second camera control unit related to the control of exposure time.

[0042] Figure 16 It is a flowchart showing the sequence of processes for capturing an interference image.

[0043] Figure 17 It is a block diagram of the functions of the second camera control unit related to the control of grayscale correction.

[0044] Figure 18 It is a diagram showing an example of the setting of grayscale correction.

[0045] Figure 19 It is a flowchart showing the sequence of processes for capturing an interference image.

[0046] Figure 20 It is a block diagram of the functions of the second camera control unit related to the control of pixel value output.

[0047] Figure 21 It is a flowchart showing the sequence of processes for capturing an interference image.

[0048] Figure 22 It is a diagram showing an example of the measurement result of the grooved part of a wafer measured by a white light interferometer.

[0049] Figure 23 It is a conceptual diagram of the setting of the output range of an image.

[0050] Figure 24 It is a block diagram of the functions of the second camera control unit related to the control of the output of an image.

[0051] Figure 25 It is a conceptual diagram of the setting of the output range of an image.

[0052] Figure 26 It is a conceptual diagram of the setting of a frame.

[0053] Figure 27 It is a block diagram of the control system for image output.

[0054] Figure 28 It is a diagram showing an example of the case where the output range of an image is set using a multi-joint frame setting.

[0055] Figure 29 It is a diagram showing another example of the frame for setting the output range of an image. Detailed implementation mode

[0056] Hereinafter, preferred implementation modes of the present invention will be described with reference to the accompanying drawings.

[0057] [First implementation mode]

[0058] Here, the case where the present invention is applied to a cutting device will be described as an example. As described above, the cutting device is a device that cuts a wafer using a blade attached to a high-speed rotating spindle. The wafer to be processed is, for example, a semiconductor wafer. On the surface of the semiconductor wafer, a plurality of ICs (Integrated Circuits) etc. are formed in a lattice-like region divided by scribe lines. The cutting device cuts the wafer along the scribe lines to individualize the ICs etc. one by one. The cutting device is an example of a processing device. The wafer is an example of a workpiece.

[0059] [Device structure]

[0060] Figure 1 It is a front view showing an implementation mode of the cutting device to which the present invention is applied. In Figure 1 , the X-axis, Y-axis, and Z-axis are mutually orthogonal axes. The plane including the X-axis and Y-axis constitutes a horizontal plane.

[0061] Figure 1The cutting device 1 shown is a so-called dual-spindle cutter. A dual-spindle cutter is a cutting device equipped with a pair of spindles. The dual-spindle cutter can adopt processing methods such as dual cut and step cut. Dual cut refers to a processing method in which a pair of blades perform full cut or half cut simultaneously on two lines. Full cut refers to a processing method in which the cutter penetrates a fixed material such as a cutting tape and completely cuts off the processing object. Half cut refers to a grooving process in which the cutter penetrates to the middle of the thickness of the processing object. Step cut refers to a processing method in which half cut and full cut are carried out in two stages.

[0062] As Figure 1 shown, the cutting device 1 has a base 2 that serves as a pedestal. On the base 2, a worktable 10 for holding the wafer W and an X-axis feed mechanism 30X for feeding the worktable 10 in the X-axis direction are provided, etc.

[0063] Figure 2 is a diagram showing the schematic structure of the worktable.

[0064] As Figure 2 shown, the worktable 10 has a disk shape and holds the wafer W on a horizontal holding surface 10A. As an example, the worktable 10 holds the wafer W by vacuum adsorption.

[0065] The wafer W as the processing object is held on the worktable 10 in a state of being mounted on a cutting frame DF as Figure 2 shown. The wafer W has a disk shape and is mounted on the cutting frame DF via a cutting tape DT.

[0066] The worktable 10 is driven by a worktable drive unit 11 to rotate about a θ-axis. The θ-axis is an axis passing through the center of the worktable 10 and parallel to the Z-axis. The worktable drive unit 11 includes a motor (not shown) and a rotational position detector. The rotational position detector is constituted by, for example, a rotary encoder and detects the rotational position of the worktable 10.

[0067] The X-axis feed mechanism 30X is a mechanism for moving the worktable 10 in the X-axis direction. As Figure 1 shown, the X-axis feed mechanism 30X is constituted by an X-axis guide rail 31X, an X-axis worktable 32X, an X-axis actuator 33X, and an X-axis position detector (not shown), etc. The X-axis guide rail 31X is provided on the base 2 along the X-axis direction. The X-axis worktable 32X is arranged to be movable on the X-axis guide rail 31X. The X-axis actuator 33X moves the X-axis worktable 32X along the X-axis guide rail 31X. The X-axis actuator 33X is constituted by, for example, a linear motor. The X-axis position detector (not shown) detects the position of the X-axis worktable 32X. The X-axis position detector is constituted by, for example, a linear scale.

[0068] The workbench 10 and the workbench drive unit 11 are arranged on the X-axis workbench 32X. By driving the X-axis actuator 33X, the X-axis workbench 32X is moved in the X-axis direction, and thus the workbench 10 is moved in the X-axis direction. In addition, by detecting the position of the X-axis workbench 32X using an X-axis position detector (not shown), the position of the workbench 10 in the X-axis direction is detected.

[0069] As Figure 1 shown, a gantry-type column 3 is provided across the X-axis guide rail 31X on the base 2. On the column 3, a first processing unit 40A and a second processing unit 40B for processing the wafer W on the workbench 10, a first imaging unit 50 and a second imaging unit 60 for photographing the wafer W on the workbench 10, a first Y-axis feeding mechanism 30YA for feeding the first processing unit 40A and the first imaging unit 50 in the Y-axis direction, a second Y-axis feeding mechanism 30YB for feeding the second processing unit 40B and the second imaging unit 60 in the Y-axis direction, a first Z-axis feeding mechanism 30ZA for feeding the first processing unit 40A and the first imaging unit 50 in the Z-axis direction, a second Z-axis feeding mechanism 30ZB for feeding the second processing unit 40B and the second imaging unit 60B in the Z-axis direction, etc. are provided.

[0070] The first processing unit 40A performs cutting processing on the wafer W using a blade 41 that rotates at high speed. The first processing unit 40A includes a first main shaft 42A for mounting the blade 41, a first main shaft motor 43A for rotating the first main shaft 42A, etc. The first main shaft 42A is arranged parallel to the Y-axis. The first main shaft 42A has a blade mounting portion at its front end. The blade 41 is detachably mounted on the blade mounting portion. By driving the first main shaft motor 43A, the first main shaft 42A rotates at high speed, and thus the blade 41 mounted on the first main shaft 42A rotates around the axis at high speed.

[0071] The second processing unit 40B performs cutting processing on the wafer W using a blade 41 that rotates at high speed. The second processing unit 40B includes a second main shaft 42B for mounting the blade 41, a second main shaft motor 43B for rotating the second main shaft 42B, etc. The second main shaft 42B is arranged parallel to the Y-axis. The second main shaft 42B has a blade mounting portion at its front end. The blade 41 is detachably mounted on the blade mounting portion. By driving the second main shaft motor 43B, the second main shaft 42B rotates at high speed, and thus the blade 41 mounted on the second main shaft 42B rotates around the axis at high speed.

[0072] The first imaging unit 50 is an imaging unit for alignment. The first imaging unit 50 magnifies and photographs a part of the surface of the wafer W on the workbench 10 from directly above.

[0073] Figure 3 is a diagram showing the schematic structure of the first imaging unit.

[0074] The first imaging unit 50 includes a first microscope unit 51 and a first camera unit 56. The first imaging unit 50 uses the first camera unit 56 to image the magnified image formed by the first microscope unit 51.

[0075] The first microscope unit 51 includes an illumination unit 52, a beam splitter 53, an objective lens 54, an imaging lens 55, etc.

[0076] The illumination unit 52 includes an illumination light source 52A and an illumination lens 52B. The illumination unit 52 emits the light (illumination light) emitted from the illumination light source 52A through the illumination lens 52B. As the illumination light source 52A, for example, a halogen lamp, a metal halide lamp, a mercury lamp, a xenon lamp, a light emitting diode (LED), etc. are used.

[0077] The light emitted from the illumination unit 52 is irradiated onto the wafer W on the worktable 10 through the beam splitter 53 and the objective lens 54. Then, the light reflected by the wafer W enters the first camera unit 56 through the objective lens 54, the beam splitter 53, and the imaging lens 55.

[0078] The first camera unit 56 includes an imaging element 56A, and electronically images the magnified image formed by the first microscope unit 51. As the imaging element 56A, for example, an area image sensor such as a CMOS image sensor (complementary metal oxide semiconductor image sensor) or a CCD image sensor (charge - coupled device image sensor) is used. The image captured by the first camera unit 56 is output to the image processing unit 110.

[0079] The second imaging unit 60 is an imaging unit for measurement. The second imaging unit 60 images the surface of the wafer W by optical interference. In particular, in the present embodiment, the surface of the wafer W is imaged by white light interference using white light as the light source. By scanning and imaging the surface of the wafer W in the Z - axis direction (height direction) by white light interference, the shape of the surface of the wafer W can be measured. Since the surface of the wafer W is imaged by white light interference, the second imaging unit 60 substantially constitutes a white light interferometer.

[0080] Figure 4 This is a diagram showing the schematic structure of the second imaging unit.

[0081] The second imaging unit 60 includes a second microscope unit 61 and a second camera unit 68. The second imaging unit 60 uses the second camera unit 68 to image the image (interference image) observed by the second microscope unit 61. The second imaging unit 60 images the surface of the wafer W from above the worktable 10 along the Z - axis direction.

[0082] The second microscope unit 61 is constituted by a white interference microscope. In the present embodiment, the second microscope unit 61 is constituted by a so-called Mirau interference type white interference microscope. As Figure 4 shown, the second microscope unit 61 includes an illumination unit 62, a first beam splitter 63, an objective lens 64, a glass plate 65, a second beam splitter 66, an imaging lens 67, etc. The glass plate 65 has a reference mirror 65A in the central portion. The objective lens 64, the glass plate 65, and the second beam splitter 66 constitute an interference optical system.

[0083] The illumination unit 62 has an illumination light source 62A and an illumination lens 62B. The illumination unit 62 emits white light emitted from the illumination light source 62A via the illumination lens 62B. For example, a halogen lamp, an LED, etc. can be used as the illumination light source 62A.

[0084] The white light emitted from the illumination unit 62 is incident on the second beam splitter 66 via the first beam splitter 63, the objective lens 64, and the glass plate 65. The white light incident on the second beam splitter 66 is separated by the second beam splitter 66 into measurement light and reference light.

[0085] The measurement light passes through the second beam splitter 66 and is incident on the surface of the wafer W. And, the measurement light reflected by the surface of the wafer W is incident on the second camera unit 68 via the second beam splitter 66, the glass plate 65, the objective lens 64, the first beam splitter 63, and the imaging lens 67.

[0086] The reference light is reflected by the second beam splitter 66 and is incident on the glass plate 65. The reference light incident on the glass plate 65 is reflected by the reference mirror 65A and is incident on the second beam splitter 66 again. And, it is reflected by the second beam splitter 66 again and is incident on the second camera unit 68 via the glass plate 65, the objective lens 64, the first beam splitter 63, and the imaging lens 67.

[0087] The measurement light incident on the second camera unit 68 after being reflected by the surface of the wafer W overlaps with the reference light incident on the second camera unit 68 after being reflected by the reference mirror 65A to generate interference light. The interference optical system constituted by the objective lens 64, the glass plate 65, and the second beam splitter 66 is designed such that the optical path lengths of the measurement light and the reference light are equal when the focus is aligned with the measurement object.

[0088] The second camera unit 68 has an imaging element 68A and electronically captures an image (interference image) generated by the second microscope unit 61. In the imaging element 68A, for example, an area image sensor such as a CMOS image sensor or a CCD image sensor is used. The image (interference image) captured by the second camera unit 68 is output to the image processing unit 110.

[0089] When the second imaging unit 60 is moved in the Z-axis direction (height direction), the optical path length of the measurement light reflected from the surface of the wafer W changes. The interference intensity of the interference light incident on the imaging element 68A becomes maximum when the optical path lengths thereof match each other. Therefore, by reading the position in the Z-axis direction where the interference intensity becomes maximum for each pixel, the positions of the unevenness on the surface of the wafer W can be measured.

[0090] The first Y-axis feed mechanism 30YA is a mechanism that moves the first processing unit 40A and the first imaging unit 50 in the Y-axis direction. As Figure 1 shown, the first Y-axis feed mechanism 30YA includes a first Y-axis guide rail 31YA, a first Y-axis table 32YA, a first Y-axis actuator 33YA, and a first Y-axis position detector (not shown), etc. The first Y-axis guide rail 31YA is laid along the Y-axis direction on the column 3. The first Y-axis table 32YA is arranged to be movable freely on the first Y-axis guide rail 31YA. The first Y-axis actuator 33YA moves the first Y-axis table 32YA along the first Y-axis guide rail 31YA. The first Y-axis actuator 33YA is constituted by a linear motor, for example. The first Y-axis position detector (not shown) detects the position of the first Y-axis table 32YA. The first Y-axis position detector is constituted by a linear scale, for example.

[0091] The second Y-axis feed mechanism 30YB is a mechanism that moves the second processing unit 40B and the second imaging unit 60 in the Y-axis direction. As Figure 1 shown, the second Y-axis feed mechanism 30YB includes a second Y-axis guide rail 31YB, a second Y-axis table 32YB, a second Y-axis actuator 33YB, and a second Y-axis position detector (not shown), etc. The second Y-axis guide rail 31YB is laid along the Y-axis direction on the column 3. The second Y-axis table 32YB is arranged to be movable freely on the second Y-axis guide rail 31YB. The second Y-axis actuator 33YB moves the second Y-axis table 32YB along the second Y-axis guide rail 31YB. The second Y-axis actuator 33YB is constituted by a linear motor, for example. The second Y-axis position detector (not shown) detects the position of the second Y-axis table 32YB. The second Y-axis position detector is constituted by a linear scale, for example.

[0092] The first Z-axis feed mechanism 30ZA is a mechanism that moves the first processing unit 40A and the first imaging unit 50 in the Z-axis direction. The first Z-axis feed mechanism 30ZA includes a first Z-axis guide rail 31ZA, a first Z-axis table 32ZA, a first Z-axis actuator 33ZA, and a first Z-axis position detector (not shown), etc. The first Z-axis guide rail 31ZA is laid along the Z-axis direction on the first Y-axis table 32YA. The first Z-axis table 32ZA is arranged to be movable freely on the first Z-axis guide rail 31ZA. The first Z-axis actuator 33ZA moves the first Z-axis table 32ZA along the first Z-axis guide rail 31ZA. The first Z-axis actuator 33ZA is composed of a linear motor, for example. The first Z-axis position detector (not shown) detects the position of the first Z-axis table 32ZA. The first Z-axis position detector is composed of a linear scale, for example.

[0093] The second Z-axis feed mechanism 30ZB is a mechanism that moves the second processing unit 40B and the second imaging unit 60 in the Z-axis direction. The second Z-axis feed mechanism 30ZB includes a second Z-axis guide rail 31ZB, a second Z-axis table 32ZB, a second Z-axis actuator 33ZB, and a second Z-axis position detector (not shown), etc. The second Z-axis guide rail 31ZB is laid along the Z-axis direction on the second Y-axis table 32YB. The second Z-axis table 32ZB is arranged to be movable freely on the second Z-axis guide rail 31ZB. The second Z-axis actuator 33ZB moves the second Z-axis table 32ZB along the second Z-axis guide rail 31ZB. The second Z-axis actuator 33ZB is composed of a linear motor, for example. The second Z-axis position detector (not shown) detects the position of the second Z-axis table 32ZB. The second Z-axis position detector is composed of a linear scale, for example.

[0094] The first processing unit 40A and the first imaging unit 50 are mounted on the first Z-axis table 32ZA via a bracket 44A. Thus, when the first Z-axis table 32ZA is moved, the first processing unit 40A and the first imaging unit 50 move in the Z-axis direction (height direction). In addition, when the first Y-axis table 32YA is moved, the first processing unit 40A and the first imaging unit 50 move in the Y-axis direction (lateral direction). Further, by detecting the position of the first Z-axis table 32ZA in the Z-axis direction using the first Z-axis position detector (not shown), the position of the blade 41 mounted on the first spindle 42A in the Z-axis direction and the position of the first imaging unit 50 in the Z-axis direction are detected. In addition, by detecting the position of the first Y-axis table 32YA in the Y-axis direction using the first Y-axis position detector (not shown), the position of the blade 41 mounted on the first spindle 42A in the Y-axis direction and the position of the first imaging unit 50 in the Y-axis direction are detected.

[0095] The second processing unit 40B and the second imaging unit 60 are mounted on the second Z-axis table 32ZB via a bracket 44B. Thus, when the second Z-axis table 32ZB is moved, the second processing unit 40B and the second imaging unit 60 move in the Z-axis direction (height direction). Further, when the second Y-axis table 32YB is moved, the second processing unit 40B and the second imaging unit 60 move in the Y-axis direction (lateral direction). Further, the Z-axis direction position of the second Z-axis table 32ZB is detected by a second Z-axis position detector (not shown), thereby detecting the Z-axis direction position of the blade 41 mounted on the second spindle 42B and the Z-axis direction position of the second imaging unit 60. Further, the Y-axis direction position of the second Y-axis table 32YB is detected by a second Y-axis position detector (not shown), thereby detecting the Y-axis direction position of the blade 41 mounted on the second spindle 42B and the Y-axis direction position of the second imaging unit 60.

[0096] Figure 5 is a block diagram of a control system of the cutting device.

[0097] The cutting device 1 includes a system controller 100 that functions as an overall control unit, an image processing unit 110 that processes images captured by the first imaging unit 50 and the second imaging unit 60, an operation unit 120 for an operator to perform various operations, a display unit 130 for displaying various information, a communication unit 140 for communicating with an external device, and the like. The communication method is not particularly limited. It may be wired communication, or it may be wireless communication. Further, it may be a communication method via a network.

[0098] The system controller 100 is composed of a computer including a processor and a memory, etc. That is, the computer functions as the system controller 100 by executing a prescribed program. The processor is, for example, a CPU (Central Processing Unit), etc. In the memory, in addition to a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, etc. are also included.

[0099] Regarding the operation of the table 10, the system controller 100 controls the table drive unit 11 and controls the rotation of the table 10. Further, the system controller 100 controls the X-axis feed mechanism 30X and controls the X-axis direction feed of the table 10. More specifically, based on the output of an X-axis position detector (not shown), the X-axis actuator 33X is controlled and the X-axis direction feed of the table 10 is controlled.

[0100] Regarding the operation of the first processing unit 40A, the system controller 100 controls the first Y-axis feed mechanism 30YA and controls the feed (indexing feed) of the first processing unit 40A in the Y-axis direction. More specifically, based on the output of a first Y-axis position detector (not shown), the first Y-axis actuator 33YA is controlled, and the feed of the first processing unit 40A in the Y-axis direction is controlled. In addition, the system controller 100 controls the first Z-axis feed mechanism 30ZA and controls the feed of the first processing unit 40A in the Z-axis direction. More specifically, based on the output of a first Z-axis position detector (not shown), the first Z-axis actuator 33ZA is controlled, and the feed of the first processing unit 40A in the Z-axis direction is controlled. Also, the system controller 100 controls the first spindle motor 43A and controls the drive of the first spindle 42A.

[0101] Regarding the operation of the second processing unit 40B, the system controller 100 controls the second Y-axis feed mechanism 30YB and controls the feed of the second processing unit 40B in the Y-axis direction. More specifically, based on the output of a second Y-axis position detector (not shown), the second Y-axis actuator 33YB is controlled, and the feed of the second processing unit 40B in the Y-axis direction is controlled. In addition, the system controller 100 controls the second Z-axis feed mechanism 30ZB and controls the feed of the second processing unit 40B in the Z-axis direction. More specifically, based on the output of a second Z-axis position detector (not shown), the second Z-axis actuator 33ZB is controlled, and the feed of the second processing unit 40B in the Z-axis direction is controlled. Also, the system controller 100 controls the second spindle motor 43B and controls the drive of the second spindle 42B.

[0102] By controlling the feed of the table 10 in the X-axis direction, the feed in the cutting direction (cutting feed) is controlled. In addition, by controlling the feeds of the first processing unit 40A and the second processing unit 40B in the Y-axis direction, the feed in the direction orthogonal to the cutting direction (indexing feed) is controlled. Also, by controlling the feeds of the first processing unit 40A and the second processing unit 40B in the Z-axis direction, the feed in the plunge direction (plunge feed) is controlled. And by controlling the feed in the plunge direction, the plunge depth is controlled.

[0103] In addition, the system controller 100 controls the first imaging unit 50 and the second imaging unit 60 and controls the imaging of the wafer W. The control regarding imaging will be described later.

[0104] The image processing unit 110 is composed of a computer including a processor, a memory, and the like. That is, the computer functions as the image processing unit 110 by executing a prescribed program. It should be noted that the computer constituting the image processing unit 110 may be the same as the computer constituting the system controller 100. That is, the same computer may function as the system controller 100 and the image processing unit 110.

[0105] Figure 6 It is a block diagram of the functions of the image processing unit.

[0106] As Figure 6 shown, the image processing unit 110 has functions such as an alignment unit 110A, a notch inspection unit 110B, and a notch shape measurement unit 110C.

[0107] The alignment unit 110A performs alignment processing in cooperation with the system controller 100. Alignment is an operation to calculate the position of the scribe lane. The position of the scribe lane is calculated, for example, based on an alignment mark. The alignment mark is a mark (also referred to as an alignment target) marked on the surface of the wafer W for alignment. The scribe lane is an area where cutting on the wafer W can be performed. The image captured by the first imaging unit 50 is processed to detect the alignment mark from within the image. It should be noted that such a technique is well-known, and thus detailed description thereof is omitted.

[0108] The notch inspection unit 110B performs notch inspection based on the image captured by the first imaging unit 50. Notch inspection is a process of confirming whether the blade 41 processes the correct position on the wafer W in an appropriate state. Notch inspection includes detection of cutting offset, detection of chipping, detection of notch width, and the like. Notch inspection is performed at a preset position at a preset frequency. It should be noted that notch inspection using an image itself is a well-known technique, and thus detailed description thereof is omitted.

[0109] The notch shape measurement unit 110C processes the image (interference image) captured by the second imaging unit 60 and measures the notch shape. Specifically, it processes a set of images (for example, a set of images with different focal planes with respect to the object) obtained by scanning and imaging the second imaging unit 60 in the Z-axis direction, and measures the three-dimensional shape of the measurement object. The measurement object is a grooved portion (notch) formed on the surface of the wafer W. As described above, the second imaging unit 60 is composed of a white light interferometer. Therefore, by scanning and imaging the measurement object in the Z-axis direction using the second imaging unit 60, the three-dimensional shape of the measurement object can be measured from the obtained set of images. It should be noted that the process of obtaining the three-dimensional shape of the measurement object from the set of images captured by the white light interferometer itself is a well-known technique. Therefore, the detailed description thereof is omitted. The notch shape measurement unit 110C generates and outputs the three-dimensional shape data of the measurement object.

[0110] Figure 7 is a block diagram of the electrical structure of the first imaging unit.

[0111] As Figure 7 shown, the first camera unit 56 includes an imaging element 56A, an analog signal processing unit 56B, an ADC (Analog to Digital Converter) 56C, a digital signal processing unit 56D, and a first camera control unit 56E.

[0112] The analog signal processing unit 56B performs prescribed analog signal processing such as correlated double sampling processing and gain adjustment on the image signal output from the imaging element 56A.

[0113] The ADC 56C converts the analog image signal obtained by performing prescribed signal processing by the analog signal processing unit 56B into a digital image signal.

[0114] The digital signal processing unit 56D performs various signal processes. Among the processes performed by the digital signal processing unit 56D, there is a process of generating image data based on the signal output from the imaging element 56A. The process of generating image data includes processes such as grayscale correction.

[0115] The first camera control unit 56E controls each part of the first camera unit 56 and the first microscope unit 51, and controls the imaging performed by the first imaging unit 50. The first camera control unit 56E is composed of a computer including a processor and a memory, etc.

[0116] Among the controls performed by the first camera control unit 56E, there is AF (Autofocus) control. The AF control is carried out in cooperation with the system controller 100. That is, scanning is performed in the Z-axis direction to detect the position (focus position) of the surface of the wafer W where the focus is aligned. The detection of the focus position is performed, for example, in a contrast method (so-called contrast AF). By detecting the focus position with respect to the surface of the wafer W, the height position (position in the Z-axis direction) of the surface of the wafer W can be detected.

[0117] The control of the first microscope unit 51 performed by the first camera control unit 56E is the control of the illumination unit 52. More specifically, it is the control of the illumination light source 52A of the illumination unit 52. The first camera control unit 56E controls the light amount (brightness) of the illumination light irradiated from the illumination light source 52A.

[0118] Figure 8 It is a block diagram of the electrical structure of the second imaging unit.

[0119] As Figure 8 shown, the second camera unit 68 includes an imaging element 68A, an analog signal processing unit 68B, an ADC 68C, a digital signal processing unit 68D, and a second camera control unit 68E.

[0120] The analog signal processing unit 68B performs prescribed analog signal processing such as correlated double sampling processing and gain adjustment on the image signal output from the imaging element 68A.

[0121] The ADC 68C converts the analog image signal obtained by performing prescribed signal processing by the analog signal processing unit 68B into a digital image signal.

[0122] The digital signal processing unit 68D performs various signal processes. Among the processes performed by the digital signal processing unit 68D, there is a process of generating image data based on the signal output from the imaging element 68A. The process of generating image data includes processes such as grayscale correction.

[0123] The second camera control unit 68E controls each part of the second camera unit 68 and the second microscope unit 61, and controls the imaging performed by the second imaging unit 60. The second camera control unit 68E is composed of a computer including a processor and a memory, etc.

[0124] The control of the imaging is carried out in cooperation with the system controller 100. As described above, the imaging performed by the second imaging unit 60 is carried out by scanning in the Z-axis direction. Therefore, the movement in the Z-axis direction is controlled by the system controller 100, and the imaging at each position is controlled by the second camera control unit 68E. Therefore, in the present embodiment, the second camera control unit 68E and the system controller 100 constitute an imaging control unit.

[0125] The control of the second microscope unit 61 performed by the second camera control unit 68E is the control of the illumination unit 62. More specifically, it is the control of the illumination light source 62A of the illumination unit 62. The second camera control unit 68E controls the light amount (brightness) of the illumination light irradiated from the illumination light source 62A. In particular, in the present embodiment, the measurement object is divided into a plurality of parts along the scanning direction, and the light amount of the illumination light is changed according to the photographed parts. A part is a portion that occupies a certain position within the entire scanning range. Each part is set as a part that can be photographed under the same conditions. In the present embodiment, the measurement object is divided into a plurality of parts along the scanning direction as parts that can be photographed with the same light amount of the illumination light.

[0126] Hereinafter, the control of the light amount of the illumination light corresponding to the photographed part (photographing part) will be described.

[0127] When measuring a groove using a shape measurement device based on an optical interference method such as a white interferometer, the reflected light from the inside of the groove becomes weak, and there is a case where the S / N ratio of the interference fringes to be obtained and the noise becomes small. As a result, there is a case where misidentification of noise occurs.

[0128] Therefore, in the present embodiment, when performing scanning and photographing in the Z-axis direction, photographing is performed while changing the light amount of the illumination light according to the photographing part (measurement part).

[0129] Figure 9 It is a conceptual diagram of the light amount control of the illumination light. Figure 9 It is an example of the case of measuring the shape of the grooved part C formed on the surface of the wafer W.

[0130] Consider the case where the second photographing unit 60 is moved downward in the vertical direction (Z-axis scanning) with respect to the wafer W on the workbench 10 to photograph the grooved part C. The photographing starts from the photographing start position Z0. The photographing start position Z0 is set at a position that is a predetermined height H from the surface of the wafer W. It should be noted that in Figure 9 , the position Z1 is the position of the surface of the wafer W. In addition, the position Z2 is the position of the bottom surface of the grooved part C. The position ZE is the photographing end position. The photographing end position is set at a position that is a predetermined distance from the position of the bottom surface of the grooved part C.

[0131] In the present embodiment, the measurement object is divided into three parts along the scanning direction, and the light amount of the illumination light is set for each part. Specifically, the part up to the surface of the wafer W is set as the first part Pz1 (Z1 ≤ Pz1 ≤ Z0), the part from the surface of the wafer W to the bottom surface of the grooved part C is set as the second part Pz2 (Z2 < Pz2 < Z1), and the part after the bottom surface of the grooved part C is set as the third part Pz3 (Pz3 ≤ Z2), and the light amount of the illumination light is set for each part.

[0132] The light quantity of the illumination light when photographing the first part Pz1 is set as the first light quantity LV1, the light quantity of the illumination light when photographing the second part Pz2 is set as the second light quantity LV2, and the light quantity of the illumination light when photographing the third part Pz3 is set as the third light quantity LV3.

[0133] The photographing of the first part Pz1 is not changed compared to the case of photographing a measurement object in normal air. Therefore, the first light quantity LV1 is set to the same light quantity as in the case of photographing a measurement object in normal air.

[0134] The photographing of the second part Pz2 is the photographing inside the grooving C. Therefore, the second light quantity LV2 is set to a value higher than the first light quantity LV1 (LV1 < LV2).

[0135] The third part Pz3 is the photographing of the bottom surface of the grooving C. Therefore, the third light quantity LV3 is preferably set according to the state of the bottom surface of the grooving C. When the bottom surface is a smooth surface, there is a case where reflected light is obtained from the bottom surface. Therefore, in this case, the third light quantity LV3 is set to a value between the first light quantity LV1 and the second light quantity LV2 (LV1 < LV3 < LV2). When the bottom surface is not a smooth surface (the case where there is almost no reflected light from the bottom surface, or the case where it is darker than the inner wall surface of the grooving C), or even when it is a smooth surface but the depth is relatively deep (the case above the threshold value), the amount of reflected light is lower than that of the second part Pz2. Therefore, in this case, it is set to a value higher than the second light quantity LV2 (LV2 < LV3).

[0136] The second camera control unit 68E acquires information (workpiece information) including information on the processed shape of the grooving C (information on the shape of the cross-section of the grooving C) and information on the state of the bottom surface of the grooving C, and based on the acquired workpiece information, performs the setting of parts and the setting of the light quantity of the illumination light for each part. And based on the set parts and light quantity, the illumination unit 52 is controlled.

[0137] Figure 10 It is a block diagram of the functions of the second camera control unit related to the control of the light quantity of the illumination light.

[0138] As Figure 10 shown, the second camera control unit 68E has the functions of a workpiece information acquisition unit 68E1, a photographing condition setting unit 68E2, and an illumination control unit 68E3.

[0139] The workpiece information acquisition unit 68E1 acquires workpiece information. As described above, the workpiece information includes information on the machining shape of the grooving C and information on the state of the bottom surface of the grooving C. The workpiece information acquisition unit 68E1 acquires the workpiece information from the system controller 100. The system controller 100 acquires the workpiece information from the operator. The operator inputs the workpiece information via the operation unit 120 or the communication unit 140.

[0140] Regarding the information on the machining shape of the grooving C (so-called cross-sectional profile), for example, the information obtained by simulation or the like is used. If the used blade 41 and the cutting depth are known, the cross-sectional shape (theoretical cross-sectional shape) of the machined grooving C is also known. Therefore, the machining shape of the grooving C is obtained by simulation or the like, and this information is used as the information on the machining shape.

[0141] It should be noted that the system controller 100 can also be configured to acquire the information on the used blade 41 and the cutting depth from the operator, and automatically calculate the information on the machining shape of the grooving C based on the acquired information.

[0142] In addition, it can also be configured to measure the grooving C machined under the same conditions, and use the result as the information on the machining shape of the object.

[0143] Alternatively, it can be that the workpiece surface is obtained by AF, and the vicinity of the third part Pz3 is scanned using the third light quantity LV3, the third part Pz3 is obtained initially, and the interval of the second part Pz2 is determined.

[0144] The shooting condition setting unit 68E2 sets shooting conditions based on the workpiece information. In the present embodiment, for each part to be shot, the light quantity of the illumination light irradiated from the illumination unit 62 is set. Specifically, the grooving C is divided into three parts (the first part Pz1, the second part Pz2, and the third part Pz3) along the Z-axis direction, and the light quantity of the illumination light during shooting (the first light quantity VL1, the second light quantity VL2, and the third light quantity VL3) is set for each part.

[0145] The information on the setting conditions of the light quantity determined for each part is stored in the memory, for example.

[0146] The illumination control unit 68E3 controls the light quantity of the illumination light irradiated from the illumination unit 62 according to the light quantity setting conditions set by the shooting condition setting unit 68E2. More specifically, it controls the illumination light source 62A of the illumination unit 62 and controls the light quantity of the illumination light irradiated from the illumination light source 62A. The illumination control unit 68E3 controls the illumination light source 62A based on the shooting position information so as to irradiate the illumination light according to the light quantity set for each part.

[0147] The illumination control unit 68E3 acquires the shooting position information from the system controller 100. The system controller 100 detects the shooting position based on the detection result of the second Z-axis position detector. It should be noted that, in the present embodiment, the shooting position is the position where the focus is aligned with the measurement object (focus position). The shooting position is synonymous with the measurement position. Structurally, since the focus position is known, the shooting position can be obtained from the position in the Z-axis direction of the second shooting unit 60.

[0148] [Function]

[0149] [Processing of wafer]

[0150] The wafer W is singulated by cutting along the scribe lanes.

[0151] First, alignment is performed. As described above, alignment is an operation for estimating the position of the scribe lane. After alignment, processing is started.

[0152] First, the blade 41 is set at a prescribed height position, and the blade 41 is rotated at high speed. The height position of the blade 41 is set to a position where a prescribed cutting depth is achieved. After the setting of the blade 41, a cutting feed (feed in the X-axis direction) is applied to the wafer W. Thereby, the wafer W is cut along the scribe lane. After cutting, an indexing feed (feed in the Y-axis direction) is applied to the blade 41. Thereby, cutting of the next scribe lane can be performed. In this way, the cutting feed and the indexing feed are alternately performed to cut the wafer W. After the cutting of all the scribe lanes in the first direction is completed, the wafer W is rotated by 90°, and the scribe lanes in the second direction are cut.

[0153] The dicing apparatus 1 of the present embodiment includes two spindles (first spindle 42A and second spindle 42B), and thus two parts can also be processed simultaneously.

[0154] The cutting method is not particularly limited. It can be processed by any method such as full cutting (processing of cutting into the dicing tape DT and completely cutting the wafer) or half cutting (notching processing of cutting into the middle of the thickness of the wafer).

[0155] [Measurement of grooving shape]

[0156] Next, the case of measuring the shape of the grooving (notch) obtained by processing will be described.

[0157] Figure 11 is a flowchart showing the sequence of the process for measuring the shape of the grooving.

[0158] First, workpiece information is acquired (step S1). As described above, the workpiece information includes information on the processed shape of the grooving C and information on the state of the bottom surface of the grooving C.

[0159] Next, based on the acquired workpiece information, shooting conditions are set (step S2). In the present embodiment, the light quantity of the illumination light when shooting each part (the first part Pz1, the second part Pz2, and the third part Pz3) is set.

[0160] Next, an interference image is shot under the set shooting conditions (step S3).

[0161] Figure 12 It is a flowchart showing the order of the shooting process of the interference image.

[0162] First, the part to be measured of the grooved part to be measured moves to the measurement position (step S3_A0). That is, it moves to directly below the second photographing unit 60 (on the photographing optical axis).

[0163] Next, the second photographing unit 60 moves to the shooting start position (step S3_A1). As described above, the shooting start position Z0 is set to a position at a predetermined height H from the surface of the wafer W (refer to Figure 9 ). It should be noted that the position of the surface of the wafer W is measured during the alignment process.

[0164] After moving to the shooting start position, the light quantity of the illumination light is set to the first light quantity LV1 (step S3_A2). After that, the shooting of the interference image starts (step S3_A3). That is, while moving the second photographing unit 60 vertically downward at a constant pitch, the interference image is shot at constant intervals. More specifically, the movement at a constant pitch and the shooting are alternately repeated to shoot the interference image.

[0165] After the shooting starts, it is determined whether the shooting position has reached the second part Pz2 (step S3_A4). When it is determined that the second part Pz2 has not been reached, the shooting continues with the first light quantity LV1. On the other hand, when it is determined that the second part Pz2 has been reached, the light quantity of the illumination light is switched to the second light quantity (step S3_A5). Thereafter, the shooting is performed with the second light quantity LV2.

[0166] After the light quantity of the illumination light is switched to the second light quantity LV2, it is determined whether the shooting position has reached the third part Pz3 (step S3_A6). When it is determined that the third part Pz3 has not been reached, the shooting continues with the second light quantity LV2. On the other hand, when it is determined that the third part Pz3 has been reached, the light quantity of the illumination light is switched to the third light quantity (step S3_A7). Thereafter, the shooting is performed with the third light quantity LV3.

[0167] Thereafter, it is determined whether the shooting position has reached the shooting end position (step S3_A8). When it is determined that the shooting end position has not been reached, shooting continues with the third light quantity LV3. On the other hand, when it is determined that the shooting end position has been reached, the shooting ends (step S3_A9).

[0168] The shooting of the interference image by the second shooting unit 60 ends through the above series of processes. The interference image obtained by shooting is sequentially output to the system controller 100.

[0169] The system controller 100 outputs the image obtained by shooting to the image processing unit 110 and performs image processing on the image (step S4). That is, three-dimensional shape data of the object is generated.

[0170] As described above, according to the cutting device 1 of the present embodiment, when shooting an interference image, the light quantity of the illumination light is changed according to the part to be shot. Thereby, the interference image can be shot with an appropriate brightness. In addition, thereby, the shape of the cutting groove can be measured with good accuracy.

[0171] It should be noted that in the above example, the case where the part to be shot is divided into three parts is described, but the division scheme of the part to be shot is not limited thereto. It can also be set to a more detailed division structure. By dividing more detailedly, the light quantity of the illumination light can be controlled more detailedly.

[0172] In addition, when measuring the cutting groove C, it is preferable to set the light quantity of the illumination light according to the width (cutting width) of the cutting groove C.

[0173] [Second Embodiment]

[0174] In the present embodiment, when shooting an interference image using the second shooting unit 60, the gain is automatically adjusted according to the part to be shot.

[0175] It should be noted that except for the difference in the shooting conditions of the interference image, the structure is the same as that of the cutting device 1 of the first embodiment described above. Therefore, hereinafter, only the points related to the control of the shooting of the interference image will be described.

[0176] The gain adjustment is performed by the analog signal processing unit 68B. The second camera control unit 68E controls the analog signal processing unit 68B so as to adjust the gain according to the setting determined for each part.

[0177] Figure 13 It is a block diagram of the functions of the second camera control unit related to the control of the gain.

[0178] As Figure 13As shown, the second camera control unit 68E has the functions of a workpiece information acquisition unit 68E1, a shooting condition setting unit 68E2, and a gain control unit 68E4.

[0179] The function of the workpiece information acquisition unit 68E1 is the same as that in the above-described first embodiment. That is, it acquires workpiece information.

[0180] The shooting condition setting unit 68E2 sets shooting conditions based on the workpiece information. In the present embodiment, for each part to be shot, the setting of gain adjustment is determined. The setting of the part is the same as that in the above-described first embodiment (refer to Figure 9 )

[0181] The setting of gain adjustment when shooting the first part Pz1 is set to "gain setting 1", the setting of gain adjustment when shooting the second part Pz2 is set to "gain setting 2", and the setting of gain adjustment when shooting the third part Pz3 is set to "gain setting 3".

[0182] The shooting of the first part Pz1 does not change compared to shooting a measurement object in normal air. Therefore, the gain setting 1 is set to the same value as the gain when shooting a measurement object in normal air.

[0183] The shooting of the second part Pz2 is the shooting inside the grooving C. Therefore, the gain setting 2 is set to a value higher than the gain setting 1 (gain setting 1 < gain setting 2).

[0184] The third part Pz3 is the shooting of the bottom surface of the grooving C. Therefore, the gain setting 3 is preferably set according to the state of the bottom surface of the grooving C. In the case where the bottom surface is a smooth surface (when there is reflected light from the bottom surface), the gain setting 3 is set to a value between the gain setting 1 and the gain setting 2 (gain setting 1 < gain setting 3 < gain setting 2). On the other hand, in the case where the bottom surface is not a smooth surface (when there is almost no reflected light from the bottom surface, or when it is darker than the inner wall surface of the grooving C), or in the case where the depth of the grooving C is relatively deep (above the threshold), it is set to a value higher than the gain setting 2 (gain setting 2 < gain setting 3).

[0185] The information of the gain setting determined for each part is stored in a memory, for example.

[0186] The gain control unit 68E4 controls the analog signal processing unit 68B according to the gain setting set by the shooting condition setting unit 68E2. That is, it controls the analog signal processing unit 68B in such a way as to perform gain adjustment according to the gain setting determined for each part.

[0187] Figure 14 It is a flowchart showing the order of the shooting process of the interference image.

[0188] First, the part of the grooving to be measured moves to the measurement position (step S3_B0).

[0189] Next, the second imaging unit 60 moves to the imaging start position (step S3_B1).

[0190] After moving to the imaging start position, the setting of gain adjustment is set to "gain setting 1" (step S3_B2), and the imaging of the interference image starts (step S3_B3).

[0191] After the imaging starts, it is determined whether the imaging position has reached the second part Pz2 (step S3_B4). When it is determined that the second part Pz2 has not been reached, the gain setting 1 is maintained and the imaging of the interference image continues. That is, the interference image is imaged with the gain adjustment of the gain setting 1. On the other hand, when it is determined that the second part Pz2 has been reached, the setting of the gain adjustment is switched to "gain setting 2" (step S3_B5). Thereafter, the interference image is imaged with the gain adjustment of the gain setting 2.

[0192] After the setting of the gain adjustment is switched to the gain setting 2, it is determined whether the imaging position has reached the third part Pz3 (step S3_B6). When it is determined that the third part Pz3 has not been reached, the gain setting 2 is maintained and the imaging of the interference image continues. That is, the interference image is imaged with the gain adjustment of the gain setting 2. On the other hand, when it is determined that the third part Pz3 has been reached, the setting of the gain adjustment is switched to "gain setting 3" (step S3_B7). Thereafter, the interference image is imaged with the gain adjustment of the gain setting 3.

[0193] Thereafter, it is determined whether the imaging position has reached the imaging end position (step S3_B8). When it is determined that the imaging end position has not been reached, the gain setting 3 is maintained and the imaging of the interference image continues. That is, the interference image is imaged with the gain adjustment of the gain setting 3. On the other hand, when it is determined that the imaging end position has been reached, the imaging ends (step S3_B9).

[0194] As described above, according to the cutting device 1 of the present embodiment, the setting of the gain adjustment is switched according to the imaged part. Thereby, an image with appropriate brightness can be obtained. In addition, thereby, the shape of the grooving can be measured with high accuracy.

[0195] It should be noted that, in this example, a structure for performing gain adjustment on an analog signal (so-called analog gain adjustment) is provided, but a structure for performing gain adjustment on a digital signal (so-called digital gain adjustment) may also be provided.

[0196] In addition, in the above example, the case where the photographed part is divided into three parts is taken as an example for explanation, but the division scheme of the photographed part is not limited to this. It can also be set to a more detailed division structure. By dividing more detailedly, the gain can be adjusted more detailedly.

[0197] In addition, when measuring the grooved part C, it is preferable to set the gain according to the width of the grooved part C.

[0198] [Third Embodiment]

[0199] In the present embodiment, when the second photographing unit 60 photographs an interference image, the exposure time is automatically adjusted according to the photographed part.

[0200] It should be noted that except for the difference in the photographing conditions of the interference image, the structure of the cutting device 1 in the above first embodiment is the same. Therefore, in the following, only the points related to the control of the photographing of the interference image will be described.

[0201] As an example, in the present embodiment, the photographing element 68A has a function of a so-called electronic shutter. The second camera control unit 68E controls the photographing element 68A so as to photograph according to the exposure time determined for each part.

[0202] Figure 15 It is a block diagram of the function of the second camera control unit related to the control of the exposure time.

[0203] As Figure 15 shown, the second camera control unit 68E has the functions of a workpiece information acquisition unit 68E1, a photographing condition setting unit 68E2, and an exposure control unit 68E5.

[0204] The function of the workpiece information acquisition unit 68E1 is the same as that in the above first embodiment. That is, it acquires workpiece information.

[0205] The photographing condition setting unit 68E2 sets photographing conditions based on the workpiece information. In the present embodiment, the exposure time at the time of photographing is determined for each photographed part. The setting of the part is the same as that in the above first embodiment (refer to Figure 9 ).

[0206] Let the exposure time when photographing the first part Pz1 be "first time T1", the exposure time when photographing the second part Pz2 be "second time T2", and the exposure time when photographing the third part Pz3 be "third time T3".

[0207] The photographing of the first part Pz1 remains unchanged compared to the case of photographing a measurement object in normal air. Therefore, the first time T1 is set to the same time as the exposure time in the case of photographing a measurement object in normal air.

[0208] The photographing of the second part Pz2 is the photographing inside the cut groove C. Therefore, the second time T2 is set to a time longer than the first time T1 (the first time T1 < the second time T2).

[0209] The third part Pz3 is the photographing of the bottom surface of the cut groove C. Therefore, the third time T3 is preferably set according to the state of the bottom surface of the cut groove C. In the case where the bottom surface is a smooth surface (when there is reflected light from the bottom surface), the third time T3 is set to a time between the first time T1 and the second time T2 (the first time T1 < the third time T3 < the second time T2). On the other hand, in the case where the bottom surface is not a smooth surface (when there is almost no reflected light from the bottom surface, or when it is darker than the inner wall surface of the cut groove C), or in the case where the depth of the cut groove C is relatively deep (above the threshold value), etc., it is set to a time longer than the second time T2 (the second time T2 < the third time T3).

[0210] The setting information of the exposure time determined for each part is stored in a memory, for example.

[0211] The exposure control unit 68E5 controls the driving of the imaging element 68A according to the setting of the exposure time set by the photographing condition setting unit 68E2. That is, it controls the driving of the imaging element 68A so as to expose according to the exposure time determined for each part.

[0212] Figure 16 It is a flowchart showing the sequence of the photographing process of the interference image.

[0213] First, the part of the cut groove to be the measurement object moves to the measurement position (step S3_C0).

[0214] Next, the second photographing unit 60 moves to the photographing start position (step S3_C1).

[0215] After moving to the photographing start position, the exposure time is set to the first time T1 (step S3_C2), and the photographing of the interference image starts (step S3_C3).

[0216] After the start of shooting, it is determined whether the shooting position has reached the second part Pz2 (step S3_C4). When it is determined that the second part Pz2 has not been reached, the exposure time is maintained at the first time T1 and the interference image is continuously shot. On the other hand, when it is determined that the second part Pz2 has been reached, the exposure time is switched to the second time T2 (step S3_C5). Thereafter, the exposure time is set to the second time T2, and the interference image is shot.

[0217] After the exposure time is switched to the second time T2, it is determined whether the shooting position has reached the third part Pz3 (step S3_C6). When it is determined that the third part Pz3 has not been reached, the exposure time is maintained at the second time T2 and the interference image is continuously shot. On the other hand, when it is determined that the third part Pz3 has been reached, the exposure time is switched to the third time T3 (step S3_C7). Thereafter, the exposure time is set to the third time T3, and the interference image is shot.

[0218] Thereafter, it is determined whether the shooting position has reached the shooting end position (step S3_C8). When it is determined that the shooting end position has not been reached, the third time T3 is maintained and the interference image is continuously shot. On the other hand, when it is determined that the shooting end position has been reached, the shooting ends (step S3_C9).

[0219] As described above, according to the cutting device 1 of the present embodiment, the exposure time is switched according to the part to be shot. Thereby, an image with appropriate brightness can be obtained. In addition, thereby, the shape of the cutting groove can be accurately measured.

[0220] It should be noted that, in the above example, the case where the part to be shot is divided into three parts is taken as an example for description, but the division scheme of the part to be shot is not limited thereto. It can also be set to a more detailed division structure. By dividing more detailedly, the exposure time can be controlled more detailedly.

[0221] In addition, when measuring the cutting groove C, it is preferable to set the exposure time according to the width of the cutting groove C.

[0222] [Fourth Embodiment]

[0223] In the present embodiment, when the second photographing unit 60 photographs the interference image, the gradation is automatically corrected according to the part to be photographed.

[0224] It should be noted that, except for the difference in the shooting conditions of the interference image, the structure is the same as that of the cutting device 1 of the first embodiment described above. Therefore, in the following, only the points related to the control of the shooting of the interference image will be described.

[0225] The gray-scale correction is performed by the digital signal processing unit 68D. The second camera control unit 68E controls the digital signal processing unit 68D so as to perform gray-scale correction according to the settings determined for each part.

[0226] Figure 17 It is a block diagram of the functions of the second camera control unit related to the control of gray-scale correction.

[0227] As Figure 17 shown, the second camera control unit 68E has the functions of a workpiece information acquisition unit 68E1, a shooting condition setting unit 68E2, and a gray-scale control unit 68E6.

[0228] The function of the workpiece information acquisition unit 68E1 is the same as that in the above-described first embodiment. That is, it acquires workpiece information.

[0229] The shooting condition setting unit 68E2 sets shooting conditions based on the workpiece information. In the present embodiment, for each part to be shot, the setting of gray-scale correction is determined. The setting of the part is the same as that in the above-described first embodiment (refer to Figure 9 ).

[0230] The setting of gray-scale correction when shooting the first part Pz1 is set to "gray-scale setting 1", the setting of gray-scale correction when shooting the second part Pz2 is set to "gray-scale setting 2", and the setting of gray-scale correction when shooting the third part Pz3 is set to "gray-scale setting 3".

[0231] Figure 18 It is a diagram showing an example of the setting of gray-scale correction. Figure 18 It is an example showing the case where the captured image is an 8-bit image (8-bit image). That is, it is an example showing the case where the gray-scale of the image is expressed in 256 gray-scales.

[0232] The shooting of the first part Pz1 remains unchanged compared to the case of shooting a measurement object in normal air. Therefore, the gray-scale setting 1 is set to the same setting as the setting of gray-scale correction when shooting a measurement object in normal air. Figure 18 (A) shows an example of the gray-scale transformation characteristic of the gray-scale setting 1. In this example, it is set to a setting where the input and output have a linear relationship.

[0233] The shooting of the second part Pz2 is the shooting inside the cut groove C. Therefore, the gray-scale setting 2 is set to the setting for shooting a darker area. Specifically, it is set to a setting that amplifies darker input data. Figure 18 (B) shows an example of the gray-scale transformation characteristic of the gray-scale setting 2. In this example, it is set to a relationship that amplifies darker input data. In Figure 18In the example shown in (B), it is set that the input 100 becomes the maximum (255).

[0234] The third part Pz3 is the photographing of the bottom surface of the grooving C. Therefore, the gray scale setting 3 is preferably set according to the state of the bottom surface of the grooving C. In the case where the bottom surface is a smooth surface (when there is reflected light from the bottom surface), it is set to a setting intermediate between the gray scale setting 1 and the gray scale setting 2. Figure 18 (C) shows an example of the gray scale conversion characteristic of the gray scale setting 3 in this case. In the example shown in this figure, it is set that the input 150 becomes the maximum (255). On the other hand, in the case where the bottom surface is not a smooth surface (when there is almost no reflected light from the bottom surface, or when it is darker than the inner wall surface of the grooving C), or in the case where the depth of the grooving C is relatively deep (above the threshold), etc., it is set to the setting when photographing a region darker than the gray scale setting 2. Figure 18 (D) shows an example of the gray scale conversion characteristic of the gray scale setting 3 in this case. In the example shown in this figure, it is set that the input 50 becomes the maximum (255).

[0235] Figure 18 This is an example for the case where the photographed image is an 8-bit image. However, in the case where the photographed image is a 14-bit image (14-bit image), the image is expressed in 16384 gray scales (0 to 16383).

[0236] Gray scale correction is performed, for example, using a table (gray scale conversion table) such as a lookup table (LUT). In this case, the gray scale conversion table to be used is determined for each photographed part.

[0237] Information on the setting of gray scale correction (setting of the gray scale conversion table to be used) determined for each part is stored in a memory, for example.

[0238] The gray scale control unit 68E6 controls the digital signal processing unit 68D in such a way that gray scale correction is performed for each part according to the setting of gray scale correction determined by the photographing condition setting unit 68E2.

[0239] Figure 19 This is a flowchart showing the order of the photographing process of the interference image.

[0240] First, it is assumed that the part of the grooving to be measured of the object to be measured moves to the measurement position (step S3_D0).

[0241] Next, the second photographing unit 60 moves to the photographing start position (step S3_D1).

[0242] After moving to the shooting start position, the grayscale correction setting is set to "Grayscale Setting 1" (step S3_D2), and the shooting of the interference image is started (step S3_D3).

[0243] After the start of shooting, it is determined whether the shooting position has reached the second part Pz2 (step S3_D4). When it is determined that the second part Pz2 has not been reached, the grayscale setting 1 is maintained and the shooting of the interference image is continued. That is, the interference image is shot with the grayscale correction performed with the grayscale setting 1. On the other hand, when it is determined that the second part Pz2 has been reached, the grayscale correction setting is switched to "Grayscale Setting 2" (step S3_D5). Thereafter, the interference image is shot with the grayscale correction performed with the grayscale setting 2.

[0244] After the grayscale correction setting is switched to the grayscale setting 2, it is determined whether the shooting position has reached the third part Pz3 (step S3_D6). When it is determined that the third part Pz3 has not been reached, the grayscale setting 2 is maintained and the shooting of the interference image is continued. That is, the interference image is shot with the grayscale correction performed with the grayscale setting 2. On the other hand, when it is determined that the third part Pz3 has been reached, the grayscale correction setting is switched to "Grayscale Setting 3" (step S3_D7). Thereafter, the interference image is shot with the grayscale correction performed with the grayscale setting 3.

[0245] Thereafter, it is determined whether the shooting position has reached the shooting end position (step S3_D8). When it is determined that the shooting end position has not been reached, the grayscale setting 3 is maintained and the shooting of the interference image is continued. That is, the interference image is shot with the grayscale correction performed with the grayscale setting 3. On the other hand, when it is determined that the shooting end position has been reached, the shooting ends (step S3_D9).

[0246] As described above, according to the cutting device 1 of the present embodiment, the grayscale correction setting is switched according to the part to be shot. Thereby, an image with appropriate brightness can be obtained. In addition, thereby, the shape of the cutting groove can be accurately measured.

[0247] It should be noted that, in the above example, the case where the part to be shot is divided into three parts is described as an example, but the division scheme of the part to be shot is not limited thereto. It is also possible to adopt a structure in which the division is made in more detail. By dividing in more detail, the grayscale of the shot image can be adjusted in more detail.

[0248] In addition, when measuring the cutting groove C, it is preferable to change the output range of the pixel value (brightness value) according to the width of the cutting groove C.

[0249] [Fifth Embodiment]

[0250] In the present embodiment, when the second photographing unit 60 photographs the interference image, the output range of the pixel value (brightness value) is switched according to the part to be photographed.

[0251] It should be noted that, except for the different shooting conditions of the interference image, the structure is the same as that of the cutting device 1 of the above first embodiment. Therefore, hereinafter, only the points related to the control of the shooting of the interference image will be described.

[0252] The process of adjusting the output range of the pixel values is performed by the digital signal processing unit 68D. The second camera control unit 68E controls the digital signal processing unit 68D so as to output pixel values according to the output range determined for each part.

[0253] Figure 20 It is a block diagram of the functions of the second camera control unit related to the control of the output of pixel values.

[0254] As Figure 20 shown, the second camera control unit 68E has the functions of a workpiece information acquisition unit 68E1, a shooting condition setting unit 68E2, and a pixel output control unit 68E7.

[0255] The function of the workpiece information acquisition unit 68E1 is the same as that of the above first embodiment. That is, it acquires workpiece information.

[0256] The shooting condition setting unit 68E2 sets shooting conditions based on the workpiece information. In this embodiment, for each part to be shot, the output range of the pixel values is determined. The setting of the part is the same as that of the above first embodiment (refer to Figure 9 ).

[0257] The setting of the output range when shooting the first part Pz1 is set as "output setting 1", the setting of the output range when shooting the second part Pz2 is set as "output setting 2", and the setting of the output range when shooting the third part Pz3 is set as "output setting 3".

[0258] The shooting of the first part Pz1 does not change compared to shooting a measurement object in normal air. Therefore, the output setting 1 is set to the same setting as shooting a measurement object in normal air. For example, in the case of an 8-bit image (an image with pixel values from 0 to 255), it is set to output pixel values of 100 or more (pixels with pixel values less than 100 output pixel values as 0 or a null value).).

[0259] The shooting of the second part Pz2 is the shooting inside the cutting groove C. Therefore, the output setting 2 is set to the setting for shooting a darker area. For example, in the case of an 8-bit image, it is set to output pixel values of 0 or more and less than 100 (pixels with pixel values of 100 or more output pixel values as 0 or a null value).).

[0260] The third part Pz3 captures the bottom surface of the grove C. Therefore, the output setting 3 is preferably set according to the state of the bottom surface of the grove C. When the bottom surface is a smooth surface (when there is reflected light from the bottom surface), it is set to a value intermediate between the output setting 1 and the output setting 2. For example, in the case of an 8-bit image, it is set to output pixel values of 50 or more and less than 150 (pixel values less than 50 and 150 or more are output as 0 or NULL). On the other hand, when the bottom surface is not a smooth surface (when there is almost no reflected light from the bottom surface, or when it is darker than the inner wall surface of the grove C), or when the depth of the grove C is relatively deep (above the threshold value), etc., it is set to the setting for capturing a region darker than the output setting 2. For example, in the case of an 8-bit image, it is set to output pixel values of 0 or more and less than 50 (pixel values of 50 or more are output as 0 or NULL).

[0261] The output range of the pixel values is controlled, for example, by filtering processing. In this case, the filter used is set for each part. Information on the setting of the output range of the pixel values determined for each part (the setting of the filter used) is stored in a memory, for example.

[0262] The pixel output control unit 68E7 controls the digital signal processing unit 68D to output pixel values according to the setting determined by the shooting condition setting unit 68E2. By restricting the output range of the pixel values, image data is generated in which the pixel values of the restricted pixels become 0 or NULL.

[0263] Figure 21 It is a flowchart showing the order of the shooting process of the interference image.

[0264] First, the part of the grove to be measured is moved to the measurement position (step S3_E0).

[0265] Next, the second shooting unit 60 is moved to the shooting start position (step S3_E1).

[0266] After moving to the shooting start position, the output range setting is set to "output setting 1" (step S3_E2), and the shooting of the interference image is started (step S3_E3).

[0267] After the start of shooting, it is determined whether the shooting position has reached the second part Pz2 (step S3_E4). When it is determined that the second part Pz2 has not been reached, the output setting 1 is maintained and the interference image is continuously shot. That is, the pixel values are output within the output range determined by the output setting 1. On the other hand, when it is determined that the second part Pz2 has been reached, the setting of the output range is switched to "output setting 2" (step S3_E5). Thereafter, the pixel values are output within the output range determined by the output setting 2.

[0268] After the setting of the output range is switched to the output setting 2, it is determined whether the shooting position has reached the third part Pz3 (step S3_E6). When it is determined that the third part Pz3 has not been reached, the output setting 2 is maintained and the interference image is continuously shot. That is, the pixel values are output within the output range determined by the output setting 2. On the other hand, when it is determined that the third part Pz3 has been reached, the setting of the output range is switched to "output setting 3" (step S3_E7). Thereafter, the pixel values are output within the output range determined by the output setting 3.

[0269] Thereafter, it is determined whether the shooting position has reached the shooting end position (step S3_E8). When it is determined that the shooting end position has not been reached, the output setting 3 is maintained and the interference image is continuously shot. That is, the pixel values are output within the output range determined by the output setting 3. On the other hand, when it is determined that the shooting end position has been reached, the shooting ends (step S3_E9).

[0270] As described above, according to the cutting device 1 of the present embodiment, the output range of the pixel values is restricted according to the part to be shot. Thereby, it is possible to suppress the inclusion of noise components in the image. In addition, thereby, the shape of the grooving can be accurately measured.

[0271] It should be noted that, in the above example, the case where the part to be shot is divided into three parts is described as an example, but the scheme of dividing the part to be shot is not limited thereto. It is also possible to adopt a structure in which the division is more detailed. By dividing more detailedly, the output range of the pixel values can be controlled more detailedly.

[0272] In addition, when measuring the grooving C, it is preferable to set the output range of the pixel values according to the width of the grooving C.

[0273] [Sixth Embodiment]

[0274] Figure 22 It is a diagram showing an example of the measurement result of the grooving of the wafer measured by the white interferometer. This diagram is a diagram obtained by projecting the three-dimensional shape data onto a two-dimensional cross section (the YZ cross section of the grooving C).

[0275] As Figure 22As shown, when measuring the grooved portion C formed on the surface of the wafer using a white light interferometer, noise may be generated near the surface of the wafer W. In addition, near the surface, interference fringes may be reflected inside the groove. Further, ghost-like interference fringes may be generated inside the groove.

[0276] These noises and interference fringes that do not originally occur in any region become factors of instability and false detection when extracting the original shape.

[0277] Therefore, in the present embodiment, only the region required for shape extraction is extracted from the captured interference image, and the extracted image is output to the system controller 100 as the captured image. That is, the regions that are not required for the measurement are cut off and output. Thereby, factors of instability and false detection when extracting the original shape can be eliminated.

[0278] Figure 23 It is a conceptual diagram of setting the output range of the image.

[0279] Figure 23 An example of measuring the shape of the grooved portion C is shown. In Figure 23 the thick line L shows the contour shape of the cross section (YZ cross section) of the grooved portion C. In addition, the region shown by the slanted lines (hatched region) shows an example of the set output range.

[0280] When measuring the grooved portion C, the positions of the surface Fa1 of the wafer, the inner wall surface Fa2 of the grooved portion C, and the bottom surface Fa3 of the grooved portion C are extracted from the image. Therefore, the range including these surfaces is set as the output range of the image. In Figure 23 the example shown, a range with a constant width centered on the position of the surface to be extracted is set as the output range. Thereby, only the region required for shape extraction can be extracted and output.

[0281] The setting of the output range of the image and its control are performed by, for example, the second camera control unit 68E. The second camera control unit 68E sets the output range of the image based on, for example, the workpiece information.

[0282] The process of adjusting the output range of the image is performed by the digital signal processing unit 68D. The second camera control unit 68E controls the digital signal processing unit 68D so as to output the image according to the setting.

[0283] Figure 24 It is a block diagram of the functions of the second camera control unit related to the control of the output of the image.

[0284] As Figure 24As shown, the second camera control unit 68E has the functions of a workpiece information acquisition unit 68E1, an image output range setting unit 68E8, and an image output control unit 68E9.

[0285] The function of the workpiece information acquisition unit 68E1 is the same as that of the first embodiment described above. That is, it acquires workpiece information.

[0286] Based on the workpiece information, the image output range setting unit 68E3 sets the output range of the image. The output range of the image is set for each shooting position in the Z-axis direction.

[0287] As described above, the output range of the image is set so as to include the extracted surfaces (the surface of the wafer W, the inner wall surface of the cut groove C, and the bottom surface of the cut groove C) (refer to Figure 23 ). For example, a range with a constant width is set as the output range of the image based on the position of the extracted surface. The output range of the image is set based on the information on the processing shape of the cut groove C (information on the shape of the cross section of the cut groove C).

[0288] The image output control unit 68E9 controls the digital signal processing unit 68D to output the image according to the output range set by the image output range setting unit 68E8. That is, it controls the digital signal processing unit 68D to output the image according to the output range determined for each shooting position in the Z-axis direction.

[0289] The digital signal processing unit 68D sets the pixel values of the pixels outside the output range to 0 or NULL and outputs the image. The output image is given to the image processing unit 110 for generating three-dimensional shape data.

[0290] In this way, according to the present embodiment, only the region required for shape extraction is extracted from the captured interference image, and the extracted image is output as the captured image. Thus, the regions that are not required for measurement are cut off and output. As a result, the unstable factors and false detection factors in extracting the original shape can be eliminated, and stable measurement can be performed.

[0291] It should be noted that in the above example, the structure is such that the process of adjusting the output range of the image is performed on the side of the second shooting unit 60, but it may also be a structure in which the same process is performed using a unit other than the second shooting unit 60. For example, it may be a structure using the system controller 100. Or, it may be a structure using an additionally provided unit, or it may be a structure using the image processing unit 110.

[0292] [Seventh Embodiment]

[0293] In the present embodiment, the output range of an image is automatically set based on the captured image. Specifically, the position of the interface of the measurement object (or a specified surface and the intersection points of this surface with other intersecting surfaces) is recognized from the captured interference image, and the output range is automatically set. In the case of the grooving C, the positions of the surface of the wafer W, the inner wall surface of the grooving C, and the bottom surface of the grooving C are recognized from the captured interference image, and the output range is set.

[0294] Figure 25 It is a conceptual diagram of the setting of the output range of the image.

[0295] Figure 25 It is an example showing the case of measuring the shape of the grooving C. In Figure 25 the thick line L shows the contour shape of the cross-section (YZ cross-section) of the grooving C.

[0296] In the case of the grooving C, the surface of the wafer, the inner wall surface of the grooving C, and the bottom surface of the grooving C are set as extraction objects. Therefore, a constant range including the surface of the wafer, the inner wall surface of the grooving C, and the bottom surface of the grooving C is set as the output range of the image. In the present embodiment, a range with a constant width centered on the position of each surface is set as the output range of the image.

[0297] In Figure 25 the ranges shown by the rectangular frames F1 and F5 are the output ranges of the image set for the surface of the wafer. In addition, the ranges shown by the rectangular frames F2 and F4 are the output ranges of the image set for the inner wall surface of the grooving C. In addition, the range shown by the rectangular frame F3 is the output range of the image set for the bottom surface of the grooving C. Each of the frames F1 to F5 has a structure in which adjacent frames are connected at their ends. For example, the frame F2 connects one end of the frame F1 to one end of the frame F3, and the frame F4 connects one end of the frame F5 to one end of the frame F3.

[0298] In the present embodiment, the frames F1 to F5 are set on each surface (the surface of the wafer, the inner wall surface of the grooving C, the bottom surface of the grooving C) recognized from the image, and the output range of the image is dynamically set.

[0299] Figure 26 It is a conceptual diagram of the setting of the frame.

[0300] Figure 26 The (A) of

[0301] shows the setting state of the frames F1 to F5 at the start of shooting. At the start of shooting, the frames F1 to F5 are in a state of being arranged in a horizontal row.

[0302] Figure 26(B) shows the setting states of frames F1 to F5 when the surface of the wafer is recognized. When the position of the surface of the wafer is recognized from the image, the movement of frames F1 and F5 stops. In addition, the position of the edge is adjusted. Thereby, the output range of the image set for the surface of the wafer is determined.

[0303] Figure 26 (C) shows the setting states of frames F1 to F5 during the process of photographing the inner wall surface of the cutting groove C. Frames F2 and F4 are configured as frames that can expand and contract (so-called rubber bands). As described above, when the position of the surface of the wafer is recognized, the movement of frames F1 and F5 stops. On the other hand, regarding frames F2 to F4, they continue to move in conjunction with the movement of the photographing position. At this time, frames F2 and F4 expand between frames F1, F5 and frame F3. At this time, frames F2 and F4 adjust the inclination based on the position of the inner wall surface of the cutting groove C recognized from the image and expand. Thereby, the output range of the image set for the inner wall surface of the cutting groove C is determined.

[0304] Figure 26 (D) shows the setting states of frames F1 to F5 when the bottom surface of the cutting groove C is recognized. When the position of the bottom surface of the cutting groove C is recognized from the image, the movement of frame F3 stops. Thereby, the output range of the image set for the bottom surface of the cutting groove C is determined.

[0305] Thus, in the present embodiment, each surface (the surface of the wafer, the inner wall surface of the cutting groove C, the bottom surface of the cutting groove C) of the extraction object is recognized from the image, frames F1 to F5 are set, and the output range of the image is dynamically set. In other words, the positions of the interfaces are tracked, frames F1 to F5 are set, and the output range of the image is set.

[0306] Figure 27 is a block diagram of the control system for image output.

[0307] The control of image output is carried out in cooperation with the second camera control unit 68E and the digital signal processing unit 68D. Regarding the control of image output, the second camera control unit 68E has the functions of an image output range setting unit 68E8 and an image output control unit 68E9. In addition, the digital signal processing unit 68D has the functions of a buffer processing unit 68D1, an image recognition unit 68D2, and an image output processing unit 68D3.

[0308] The buffer processing unit 68D1 performs buffer processing on the image data of the processing object. That is, it performs the process of temporarily storing in the memory. The image data is stored in the memory in time series.

[0309] The image recognition unit 68D2 analyzes the captured image and recognizes the surface of the extraction object. In this embodiment, since the grooved portion C is set as the measurement object, the surface of the wafer W, the inner wall surface of the grooved portion C, and the bottom surface of the grooved portion C are recognized. In image recognition, a known method can be adopted. For example, regarding the surface of the wafer W, a method can be adopted in which the time point when the number of points with a strong interference intensity inside the frames F1 and F5 becomes a state where it can be recognized as the surface (using feature quantities such as the number of points, area, and Hough approximation line) is recognized as the surface. Similarly, for the bottom surface of the grooved portion C, a method can be adopted in which the time point when the number of points with a strong interference intensity inside F3 becomes a state where it can be recognized as the bottom surface is recognized as the bottom surface. In addition, regarding the inner wall surface of the grooved portion C, the inclination angle is obtained from the perspective of the arrangement analysis region of the candidate points (for example, the inclination of the Hough line, the inclination of the least squares straight line, and the inclination of the major axis of the point sequence).

[0310] The image output range setting unit 68E8 sets the output range of the image based on the recognition result of the surface of the extraction object recognized by the image recognition unit 68D2. In this embodiment, the frames F1 to F5 are set, and the image output range at each surface (the surface of the wafer, the inner wall surface of the grooved portion C, and the bottom surface of the grooved portion C) is set.

[0311] The image output control unit 68E9 causes the image output processing unit 68D3 to perform image output processing based on the output range set by the image output range setting unit 68E8.

[0312] The image output processing unit 68D3 processes the image data stored in the memory based on the instruction of the image output control unit 68E9 and generates image data for output. That is, the image within the set output range is extracted and image data for output is generated. The generation of the image data for output generates an image in which the area outside the range set as the output range is set to 0 or NULL (empty).

[0313] In this way, in this embodiment, the captured image is recognized and the output range of the image is set. Thereby, the output range can be appropriately set.

[0314] In the above example, the frames F2 and F4 for setting the output range of the inner wall surface of the grooved portion C are constituted by a telescopic frame, but a so-called multi-joint frame can also be used for the constitution.

[0315] Figure 28 FIG. is an example showing a case where a multi-joint frame is used to set the output range of an image.

[0316] Figure 28 An example showing a case where the shape of a grooved portion subjected to stepped cutting is measured is shown. In stepped cutting, after semi-cutting, full cutting is performed inside the semi-cut portion. Therefore, the cross-section of the grooved portion C has a stepped portion.

[0317] The multi-jointed frames F2A and F4A are formed by continuously generating frames F2a and F4a having a constant length. Each of the frames F2a and F4a bendably connects the adjacent frames to each other. Thereby, it is possible to set the frames F2A and F4A that match the shape of the cross-section more. In particular, it is effective in the case where the inner wall surface is not linear (such as the case having a stepped portion, the case of a curved surface, etc.) like the cut groove C in this example.

[0318] Figure 29 It is a diagram showing another example of a frame for setting the output range of an image.

[0319] Figure 29 The example shown shows an example of the case where the frame is divided in pole units and set. Regarding the frames F2B and F4B for setting the output range of the inner wall surface of the cut groove C, it is set as a telescopic structure, while on the other hand, it is set as a structure that stops elongation at each pole and generates a new frame. In Figure 29 the example shown, at the end points of the stepped portion and the end points of the curved surface that become poles, the elongation of the frames F2b and F4b is stopped, and new frames F2b and F4b are generated. Thereby, it is possible to set the frames F2B and F4B that match the shape of the cross-section.

[0320] It should be noted that, in the above example, the width of the frame is set to be constant, but it may also be set as a structure that is set according to the inclination of the surface to be measured, etc.

[0321] In addition, in the case where workpiece information can be obtained, it is preferable to set each of the frames F1 to F5 using the workpiece information. For example, regarding the initial frames F1 to F5, it is preferable to set their width and length using the workpiece information. In addition, the identification of each surface is also preferably performed using the workpiece information.

[0322] Moreover, the image used in the image recognition is preferably an image captured by performing the above-described shooting control. Thereby, the image recognition becomes easy.

[0323] In addition, in the above example, it is set as a structure that performs the process of adjusting the output range of the image on the second photographing unit 60 side, but it may also be set as a structure that performs the same process using a unit other than the second photographing unit 60.

[0324] In addition, in the above, it is set as the output range of the image, but it is also possible to output the least squares line, the Hough line, and the main axis as the interface = cross-sectional shape region.

[0325] [Other Embodiments]

[0326] The above-described embodiments can be implemented by appropriate combination. That is, adjustment of the light amount of illumination light, gain adjustment, gradation correction, adjustment of exposure time, adjustment of the output range of pixel values, etc. can be appropriately combined and implemented. In addition, adjustment of the output range of an image can also be appropriately combined and implemented.

[0327] In addition, when scanning and photographing in the direction along the Z axis, the photographing conditions set for each part are not limited to the conditions of the above-described embodiments, and various conditions can be set.

[0328] In addition, in the above-described embodiment, a structure is adopted in which the generation process of three-dimensional shape data is performed by the image processing unit 110 other than the second photographing unit 60, but the second photographing unit 60 may have the function of the image processing unit 110.

[0329] In addition, in the above-described embodiment, the case where the second photographing unit 60 is constituted by a white interferometer has been described as an example, but the present invention can also be applied to the case where the second photographing unit 60 is constituted by a shape measurement device of other optical interference methods. In addition, regarding the interference optical system, in addition to the Mirau type, an interference optical system such as the Michelson type or the Fizeau type can also be adopted.

[0330] Moreover, the present invention can also be used in the case where the second photographing unit 60 is constituted by a laser microscope (an optical system microscope that uses a laser as an illumination light source and uses a confocal method in the optical system), and the case of performing photographing by the focus-variation method.

[0331] In addition, in the above-described embodiment, the case where the present invention is applied to a so-called double-spindle cutter has been described as an example, but the application of the present invention is not limited thereto. The number of spindles mounted on the device can be 1, or can also be 3 or more. In addition, in the above-described embodiment, the case of processing a semiconductor wafer has been described as an example, but the processing object is not limited thereto.

[0332] In addition, in the above-described embodiment, a structure is adopted in which the drive unit of the second photographing unit 60 and the drive unit of the second processing unit 40B are shared, but a structure having respective independent drive units can also be adopted. Or, a structure may be adopted in which a measurement unit is additionally provided in the device and measurement is performed using the measurement unit.

[0333] In addition, in the above-described embodiment, a structure is adopted in which the second photographing unit 60 side is moved when scanning and photographing in the Z-axis direction, but a structure in which the stage 10 side is moved can also be adopted. Or, a structure in which both are moved can also be adopted. That is, it is only necessary that the second photographing unit 60 can move relative to the workpiece on the stage 10 in the direction along the Z axis.

[0334] Explanation of reference numerals

[0335] 1: Cutting device, 2: Base, 3: Column, 10: Workbench, 10A: Holding surface, 11: Workbench drive unit, 30X: X-axis feed mechanism, 30YA: First Y-axis feed mechanism, 30YB: Second Y-axis feed mechanism, 30ZA: First Z-axis feed mechanism, 30ZB: Second Z-axis feed mechanism, 31X: X-axis guide rail, 31YA: First Y-axis guide rail, 31YB: Second Y-axis guide rail, 31ZA: First Z-axis guide rail, 31ZB: Second Z-axis guide rail, 32X: X-axis workbench, 32YA: First Y-axis workbench, 32YB: Second Y-axis workbench, 32ZA: First Z-axis workbench, 32ZB: Second Z-axis workbench, 33X: X-axis actuator, 33YA: First Y-axis actuator, 33YB: Second Y-axis actuator, 33ZA: First Z-axis actuator, 33ZB: Second Z-axis actuator, 40A: First processing unit, 40B: Second processing unit, 41: Blade, 42A: First main shaft, 42B: Second main shaft, 43A: First main shaft motor, 43B: Second main shaft motor, 44A: Bracket, 44B: Bracket, 50: First imaging unit, 51: First microscope unit, 52: Lighting unit, 52A: Lighting light source, 52B: Lighting lens, 53: Beam splitter, 54: Objective lens, 55: Imaging lens, 56: First camera unit, 56A: Imaging element, 56B: Analog signal processing unit, 56D: Digital signal processing unit, 56E: First camera control unit, 60: Second imaging unit, 60B: Second imaging unit, 61: Second microscope unit, 62: Lighting unit, 62A: Lighting light source, 62B: Lighting lens, 63: First beam splitter, 64: Objective lens, 65: Glass plate, 65A: Reference mirror, 66: Second beam splitter, 67: Imaging lens, 68: Second camera unit, 68A: Imaging element, 68B: Analog signal processing unit, 68D: Digital signal processing unit, 68D1: Buffer processing unit, 68D2: Image recognition unit, 68D3: Image output processing unit, 68E: Second camera control unit, 68E1: Workpiece information acquisition unit, 68E2: Shooting condition setting unit, 68E3: Lighting control unit, 68E4: Gain control unit, 68E5: Exposure control unit, 68E6: Gray scale control unit, 68E7: Pixel output control unit, 68E8: Image output range setting unit, 68E9: Image output control unit, 100: System controller, 110: Image processing unit, 110A: Alignment unit, 110B: Notch inspection unit, 110C: Notch shape measurement unit, 120: Operation unit, 130: Display unit, 140: Communication unit, C: Groove, DF: Cutting frame, DT: Cutting tape, F1: Frame, F2: Frame, F2A: Frame, F2B: Frame, F2a: Frame, F2b: Frame, F3: Frame, F4: Frame, F5: Frame, Fa1: Surface of wafer, Fa2: Inner wall surface of groove, Fa3: Bottom surface of groove, L: Contour shape of cross section of groove, W: Wafer,Z0: Starting position of shooting, Z1: Position of the surface of the wafer, Z2: Position of the bottom surface of the grooving, ZE: Ending position of shooting.

Claims

1. A processing device, wherein, The processing device includes: A worktable that holds a workpiece on a holding surface orthogonal to the Z-axis; A processing unit that processes the workpiece on the worktable; An imaging unit that images the surface of the workpiece by optical interference; A drive unit that relatively moves the imaging unit with respect to the worktable in the direction of the Z-axis; and An imaging control unit that controls the drive unit and the imaging unit to scan and image the surface of the workpiece on the worktable in the direction of the Z-axis. When scanning and imaging the surface of the workpiece in the direction of the Z-axis, the imaging control unit images according to imaging conditions determined for each imaged part.

2. The processing device according to claim 1, wherein, The imaging control unit irradiates illumination light with a light amount determined for each part and images the surface of the workpiece.

3. The processing device according to claim 1, wherein, The imaging control unit performs gain adjustment with a setting determined for each part and images the surface of the workpiece.

4. The processing device according to claim 1, wherein, The imaging control unit controls the exposure time with a setting determined for each part and images the surface of the workpiece.

5. The processing device according to claim 1, wherein, The imaging control unit performs grayscale correction with a setting determined for each part and images the surface of the workpiece.

6. The processing device according to claim 1, wherein, The imaging control unit outputs pixel values from each pixel within an output range determined for each part and images the surface of the workpiece.

7. The processing device according to claim 1, wherein, When imaging a groove machined on the surface of the workpiece, it is divided into a first part including the surface of the workpiece, a third part including the bottom surface of the groove, and a second part between the first part and the third part, and the imaging conditions are determined for each divided part.

8. The processing device according to claim 1, wherein, The processing device further includes an image processing unit that processes an image obtained by scanning and imaging the surface of the workpiece in the direction of the Z-axis to measure the shape of the surface of the workpiece.

9. The processing device according to any one of claims 1 to 8, wherein, The processing device further includes: A workpiece information acquisition unit that acquires workpiece information including information on the shape of the cross-section of the workpiece; and An imaging condition setting unit that sets the imaging conditions based on the workpiece information.

10. The processing device according to claim 9, wherein, The processing device further includes an output range setting unit that sets the output range of the image based on the information on the shape of the cross-section of the workpiece. The imaging control unit extracts and outputs an image within the range set by the output range setting unit from the captured image.

11. The processing device according to any one of claims 1 to 8, wherein, The processing device further includes an output range setting unit that analyzes the captured image to set the output range. The imaging control unit extracts and outputs an image within the range set by the output range setting unit from the captured image.

12. The processing device according to claim 11, wherein, The output range setting unit analyzes the captured image to identify the interface of the workpiece and sets a specified range including the identified interface as the output range.

13. The processing device according to claim 12, wherein, When imaging a groove machined on the surface of the workpiece, the output range setting unit identifies the surface of the workpiece, the inner wall surface of the groove, and the bottom surface of the groove, and sets a specified range including the identified surfaces as the output range.

14. The processing device according to any one of claims 1 to 8, wherein, The imaging unit images the surface of the workpiece by white light interference.

Images