Processing quality measuring device

Abstract

To provide a processing quality measurement device capable of accurately measuring processing quality of a processed portion formed on a workpiece.SOLUTION: A processing quality measurement device comprises: a white light interferometer 24 that is provided integrally with a processing head, the white light interferometer 24 emitting white light toward a processed portion formed on a workpiece W and detects an interference signal of the white light reflected at the processed portion and the white light reflected at a reference surface; a scanning control unit (movement control unit 72) that drives a relative movement mechanism 49 to perform vertical scanning of the processing head and the white light interferometer 24 so as to vary an optical path length of the white light reflected at the processed portion; and a processing quality measurement unit 82 that measures the processing quality of the processed portion on the basis of the interference signal output from the white light interferometer 24 during the vertical scanning.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a workpiece processing apparatus for processing a workpiece, a control method for the workpiece processing apparatus, and a server connected to the workpiece processing apparatus.

Background Art

[0002] A dicing apparatus (workpiece processing apparatus) that cuts a workpiece such as a wafer with a disk-shaped blade rotated at high speed by a spindle is known. Since the blade of this dicing apparatus wears out during use, chipping may occur on the cut surface of the workpiece by the blade. Further, due to the influence of thermal deformation of the blade, the position of the groove (kerf) formed in the workpiece by the blade may deviate from the center of the street. Therefore, in the dicing apparatus, a kerf check of the blade is performed at a preset timing. For example, in a dicing apparatus, a groove formed in a workpiece by a blade is photographed with a camera (such as a microscope for alignment), and based on the photographed image of this camera, the kerf position, kerf width, and presence or absence of chipping of the groove are measured (see Patent Document 1).

[0003] By the way, as a dicing apparatus, a twin spindle dicer having two spindles on which blades are mounted is known. And, as a method of cutting or severing a workpiece with a twin spindle dicer, a meeting cutting method and a step cut method are known. The meeting cutting method is a method of cutting two streets at once with two blades. Further, the step cut method is a method of cutting a wafer along a street by cutting a groove having a predetermined depth along the street with a first blade and then cutting the bottom of the groove with a second blade.

[0004] Two methods are known for performing kerf checks on the two blades of a twin-spindle dicer employing a step-cutting method. In the first method, the first blade cuts the wafer to a predetermined depth along the street, and the cut groove is photographed with a camera. Based on the image of this groove, a kerf check of the first blade is performed. Next, the bottom of the groove cut by the first blade is cut with the second blade, and the groove cut by the second blade is photographed with a camera. Based on the image of this groove, a kerf check of the second blade is performed.

[0005] In the second method, an uncut portion of the workpiece is cut with the first blade, and another uncut portion of the workpiece is cut with the second blade. Based on the images captured by a camera of the two grooves formed by each blade, a calf check of each blade is performed (see Patent Document 2). This calf check in the second method is also called a step calf check or overtake calf check. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2011-165826 [Patent Document 2] Japanese Patent Publication No. 2001-129822 [Overview of the project] [Problems that the invention aims to solve]

[0007] Figure 34 is an explanatory diagram illustrating the challenges of the calf check in the first method described above. As shown in Figure 34, when performing a calf check using the first method, the groove 25B formed in the workpiece W by the second blade overlaps with the groove 25A formed in the workpiece W by the first blade, making it difficult to determine the processing quality of groove 25B (calf position, calf width, etc.) based on the captured image of groove 25B. As a result, there is a drawback that calf checks of the second blade are extremely difficult.

[0008] Figure 35 is an explanatory diagram illustrating the challenges of the kerf check in the second method described above. As shown in Figure 35, when performing a kerf check using the second method, it is necessary to cut the uncut areas of the workpiece W with the second blade. However, since the second blade is thinner than the first blade, cutting the uncut areas with the second blade places a large load on it. Furthermore, because the processing conditions of the workpiece by the second blade differ between step cutting and kerf checking, for example, the second blade may twist during kerf checking, potentially forming a groove 25B in a different position than during step cutting. In other words, there is a possibility that the groove 25B will not be formed in the same position during step cutting and kerf checking, and as a result, it may not be possible to accurately measure the processing quality of the groove 25B during step cutting.

[0009] This invention has been made in view of these circumstances, and aims to provide a workpiece processing device that can accurately measure the processing quality of a workpiece formed on a workpiece, a control method for this workpiece processing device, and a server connected to this workpiece processing device. [Means for solving the problem]

[0010] A workpiece processing apparatus for achieving the object of the present invention comprises: a table for holding a flat workpiece; a processing head for processing the workpiece held on the table; a relative movement mechanism for moving the processing head relative to the table; a white light interferometer provided integrally with the processing head, which emits white light toward a workpiece formed on the workpiece and detects interference signals between the white light reflected by the workpiece and the white light reflected by a reference plane for each pixel; a scanning control unit that drives the relative movement mechanism to perform a vertical scan that moves the processing head and the white light interferometer together in a direction perpendicular to the table; and a processing quality measuring unit that measures the processing quality of the workpiece based on the interference signals for each pixel output from the white light interferometer during the vertical scan.

[0011] This workpiece processing device allows for accurate measurement of the processing quality of the workpiece using a white light interferometer integrated with the processing head.

[0012] In another aspect of the present invention, a workpiece processing apparatus includes a processing control unit that drives a processing head and a relative movement mechanism to form a workpiece on the workpiece using the processing head, and a first measurement control unit that operates a white light interferometer and a scanning control unit at a position where white light can be irradiated onto the workpiece, wherein the processing quality measurement unit measures at least one of the processing position and processing shape of the workpiece as processing quality. This makes it possible to accurately measure at least one of the processing position and processing shape of the workpiece using a white light interferometer.

[0013] In another aspect of the present invention, a workpiece processing apparatus is provided, which includes a correction value determination unit that determines a correction value to correct at least one of the processing position and processing shape of the workpiece based on the measurement results of a processing quality measurement unit, and a processing control unit drives a processing head and a relative movement mechanism to form a workpiece on the workpiece based on the correction value determined by the correction value determination unit. By feeding the correction value back to the processing of the next workpiece by the processing head, the processing accuracy of the next workpiece can be further improved.

[0014] In another aspect of the present invention, a workpiece processing apparatus has a first processing head and a second processing head as processing heads, and a processing control unit drives a relative movement mechanism and the first processing head to perform a first processing process in which a first groove is formed in the workpiece as a workpiece portion, and a second processing process in which the relative movement mechanism and the second processing head are driven to form a second groove at the bottom of the first groove as a workpiece portion and cut the workpiece, and a processing quality measuring unit measures the processing positions of the first groove and the second groove. As a result, even when the second groove is formed at the bottom of the first groove, as in a step-cut method, the processing position (processing quality) of this second groove can be measured with high accuracy.

[0015] In another aspect of the present invention, when the workpiece is a groove, the processing quality measuring unit measures the depth of the groove as the processed shape. This allows for accurate measurement of the groove depth.

[0016] In another aspect of the present invention, a workpiece processing apparatus is provided, which includes a second measurement control unit that operates a white light interferometer and a scanning control unit at a position where white light can be irradiated onto a first groove, which is a workpiece portion formed in advance on the workpiece by the processing head, before the workpiece is processed by the processing head. A processing quality measurement unit measures the processing position of the first groove as processing quality, and based on the measurement results of the processing quality measurement unit, a processing control unit drives the processing head and a relative movement mechanism to form a second groove at the bottom of the first groove and cut the workpiece. As a result, the processing position of the first groove can be measured with high accuracy, and the processing accuracy of the second groove by the processing head can be improved.

[0017] In another aspect of the present invention, a workpiece processing apparatus operates a second measurement control unit at a position where white light can be irradiated onto the first groove formed by the irradiation of a laser beam onto the workpiece. This allows for accurate measurement of the processing position of the first groove (laser groove) formed by the laser processing.

[0018] In another aspect of the present invention, a workpiece processing apparatus is provided, in which a processing head cuts a workpiece using a rotating disc-shaped blade.

[0019] In another aspect of the present invention, a workpiece processing apparatus includes a processing head that cuts a workpiece with a rotating disc-shaped blade, a processing control unit that drives the processing head and a relative movement mechanism to form a workpiece with the blade, and a processing quality measuring unit that measures the cross-sectional shape of the workpiece as processing quality, and a blade shape measuring unit that measures the tip shape of the blade based on the measurement result of the cross-sectional shape by the processing quality measuring unit. This allows for accurate measurement of the tip shape of the blade using a white light interferometer.

[0020] In another aspect of the present invention, a workpiece processing apparatus drives a relative movement mechanism and a processing head to form a groove in the workpiece as the workpiece portion, a processing quality measuring unit measures the cross-sectional shape of the groove, and a blade shape measuring unit measures the tip shape of the blade based on the measurement result of the cross-sectional shape by the processing quality measuring unit. This allows for accurate measurement of the tip shape of the blade.

[0021] In another aspect of the present invention, a workpiece processing apparatus is provided, which includes a rotational drive mechanism that rotates the table about the rotation axis of the table, and a processing control unit drives the processing head, relative movement mechanism, and rotational drive mechanism to cut and remove the outer periphery of the workpiece from one side of the workpiece to a predetermined depth, thereby forming a stepped portion on the outer periphery of the workpiece as the processed portion, a processing quality measuring unit measures the cross-sectional shape of the stepped portion, and a blade shape measuring unit measures the tip shape of the blade based on the measurement result of the cross-sectional shape by the processing quality measuring unit. This makes it possible to measure the tip shape of the blade with high accuracy.

[0022] A control method for a workpiece processing apparatus to achieve the object of the present invention comprises: a scanning control step of performing a vertical scan in which a white light interferometer, which emits white light toward a workpiece formed on a flat workpiece held on a table and detects interference signals between the white light reflected from the workpiece and the white light reflected from a reference surface for each pixel, is moved relative to the table in a direction perpendicular to the table, together with the processing head that processes the workpiece; and a processing quality measurement step of measuring the processing quality of the workpiece based on the interference signals for each pixel output from the white light interferometer during the vertical scan.

[0023] In another aspect of the present invention, a control method for a workpiece processing apparatus includes a processing quality measurement step in which the cross-sectional shape of the workpiece formed on the workpiece by a processing head having a rotating disc-shaped blade is measured, and a blade shape measurement step in which the tip shape of the blade is measured based on the measurement result of the cross-sectional shape of the workpiece in the processing quality measurement step.

[0024] The server for achieving the object of the present invention includes a communication interface connected to a white interferometer that emits white light toward a machined portion formed on a flat workpiece held on a table and detects, for each pixel, an interference signal between the white light reflected by the machined portion and the white light reflected by a reference surface, a machining head that performs machining on the workpiece, and an interference signal acquisition unit that acquires, via the communication interface, the interference signal for each pixel from the white interferometer while the machining head and the white interferometer are integrally and relatively moved in a direction perpendicular to the table by a relative movement mechanism, and a machining quality measurement unit that measures the machining quality of the machined portion based on the interference signal for each pixel acquired by the interference signal acquisition unit.

[0025] In the server according to another aspect of the present invention, the machining quality measurement unit measures a cross-sectional shape of a machined portion formed on a workpiece by a machining head having a rotating disk-shaped blade, and includes a blade shape measurement unit that measures a tip shape of the blade based on a measurement result of the cross-sectional shape by the machining quality measurement unit.

Effect of the Invention

[0026] The present invention can accurately measure the machining quality of a machined portion formed on a workpiece.

Brief Description of the Drawings

[0027] [Figure 1] It is a perspective view of a dicing device according to the first embodiment. [Figure 2] It is an external perspective view of a machining portion. [Figure 3] It is an enlarged front view of the white interferometer shown in FIG. 2. [Figure 4] It is a cross-sectional view of the white interferometer. [Figure 5] It is a functional block diagram of an overall control unit of the dicing device according to the first embodiment. [Figure 6] It is an explanatory diagram for explaining a meeting cutting method. [Figure 7] It is an explanatory diagram for explaining a step cut method. [Figure 8]This is a cross-sectional view of a portion of a workpiece that was cut using a step-cut method. [Figure 9] This is an explanatory diagram illustrating the measurement of the three-dimensional shape of a groove by the processing quality measurement unit. [Figure 10] This is an explanatory diagram illustrating the shape measurement of the cross-sectional shape of the groove along the Y-axis direction by the processing quality measurement unit. [Figure 11] This is an explanatory diagram illustrating an example of kerf checking of grooves formed by a step-cut method, that is, measuring the machining position of the grooves within the workpiece. [Figure 12] This is an explanatory diagram illustrating the determination of correction values ​​Δy1 and Δy2 for the machining position of grooves formed by a step-cut method using a correction value determination unit. [Figure 13] This flowchart shows the flow of the cutting process of a workpiece using the dicing apparatus of the first embodiment, particularly the flow of the measurement process for the machining quality (machining position) of the grooves. [Figure 14] This is an explanatory diagram illustrating the cutting process of a workpiece using a dicing apparatus of the second embodiment and the back surface grinding of a workpiece using a grinding (polishing) apparatus (not shown). [Figure 15] This is an explanatory diagram illustrating a chop cutter set, which is an example of a conventional method for adjusting the cutting depth of a blade. [Figure 16] This is an explanatory diagram illustrating the shape measurement of the cross-sectional shape of a half-cut groove along the Y-axis direction by the processing quality measurement unit of the second embodiment. [Figure 17] This is an explanatory diagram illustrating a workpiece after laser-cut grooves have been formed by a laser processing device (not shown) and the cutting process of a workpiece by a dicing device of the third embodiment. [Figure 18] This is an explanatory diagram illustrating the measurement of the three-dimensional shape of a laser-processed groove by the processing quality measurement unit of the third embodiment. [Figure 19] This is an explanatory diagram illustrating the shape measurement of the cross-sectional shape along the Y-axis direction of a laser-processed groove by the processing quality measurement unit of the third embodiment. [Figure 20] This is an explanatory diagram illustrating the shape of the blade tip. [Figure 21] This is an explanatory diagram illustrating the problems that arise when a workpiece is cut using an unevenly worn blade. [Figure 22] This is an explanatory diagram for demonstrating the measurement of the tip shape of conventional blades. [Figure 23] This is an explanatory diagram to illustrate the third problem. [Figure 24] This is a functional block diagram of the central control unit of the dicing apparatus according to the fourth embodiment. [Figure 25] This is an explanatory diagram illustrating the calculation result of the cross-sectional shape along the Y-axis direction of the half-cut groove by the processing quality measurement unit of the fourth embodiment. [Figure 26] This flowchart shows the flow of the blade tip shape measurement process using the dicing apparatus of the fourth embodiment. [Figure 27] This is an explanatory diagram illustrating the problems that arise from back surface grinding of the workpiece W after the formation of the half-cut groove described in the second and fourth embodiments. [Figure 28] This is an explanatory diagram illustrating the trimming process of the edge portion of a workpiece using a blade. [Figure 29] These are side views of the workpiece after trimming and after back grinding. [Figure 30] This is a magnified cross-sectional view of the stepped portion at the edge of the workpiece. [Figure 31] This is an enlarged view of the blade of the dicing device according to the sixth embodiment. [Figure 32] This is an explanatory diagram illustrating the calculation result of the axial cross-sectional shape of the half-cut groove formed by the blade of the sixth embodiment. [Figure 33] This is a functional block diagram of the server according to the seventh embodiment. [Figure 34] This is an explanatory diagram illustrating the calf check task of the first method. [Figure 35] This is an explanatory diagram illustrating the calf check task of the second method. [Modes for carrying out the invention]

[0028] [First Embodiment] Figure 1 is a perspective view of the dicing apparatus 10 according to the first embodiment. Note that the XYZ axes in the figure are mutually orthogonal axes, with the XY axes being parallel to the horizontal direction and the Z axis being perpendicular to the horizontal direction.

[0029] The dicing apparatus 10 corresponds to the workpiece processing apparatus of the present invention and cuts a flat workpiece W such as a semiconductor wafer. This dicing apparatus 10 includes a load port 12, a transport mechanism 14, a processing section 16, and a cleaning section 18.

[0030] A cassette containing numerous workpieces W mounted on a frame F is placed on the load port 12. The transport mechanism 14 transports the workpieces W. The processing unit 16 performs dicing of the workpieces W. The cleaning unit 18 spin-cleans the diced workpieces W. Inside the housing 10A of the dicing device 10, there is a control unit 60 (see Figure 5) that controls the operation of each part of the dicing device 10. The control unit 60 may be located outside the housing 10A.

[0031] The unprocessed (uncut) workpiece W stored in the cassette placed on the load port 12 is transported to the processing section 16 by the transport mechanism 14, where it is cut or grooved to separate into individual chips. The processed workpiece W from the processing section 16 is then transported to the cleaning section 18 by the transport mechanism 14, where it is cleaned, and then transported back to the load port 12 by the transport mechanism 14 and stored in the cassette.

[0032] Figure 2 is an external perspective view of the processing unit 16. As shown in Figure 2 and Figure 1 described above, the processing unit 16 is the twin spindle dicer described above and comprises a pair of blades 21A, 21B, a blade cover (not shown), a pair of spindles 22A, 22B, a microscope 23, a white light interferometer 24, and a table 31.

[0033] Blades 21A and 21B are formed in a disc shape. The tip shape of blades 21A and 21B, that is, the cross-sectional shape of the outer circumference (cutting edge) of the blades along the radial direction of blades 21A and 21B, is rectangular. Blades 21A and 21B are arranged opposite each other in the Y-axis direction and are held on spindles 22A and 22B so as to be rotatable around blade rotation axes parallel to the Y-axis direction.

[0034] The spindles 22A and 22B have built-in high-frequency motors that rotate the blades 21A and 21B at high speed around the blade rotation axis. As a result, the workpiece W is cut from its front side by the blades 21A and 21B. For this reason, the blade 21A and spindle 22A correspond to the first machining head (machining head) of the present invention. The blade 21B and spindle 22B correspond to the second machining head (machining head) of the present invention.

[0035] A groove 25A (see Figures 6 and 7), corresponding to the workpiece portion of the present invention, is formed in the workpiece W by cutting with blade 21A. In addition, a groove 25B (see Figures 6 and 7), corresponding to the workpiece portion of the present invention, is formed in the workpiece W by cutting with blade 21B.

[0036] The microscope 23 is mounted on the Z carriage 44 integrally with the spindle 22A and is held by the Y carriage 43 and Z carriage 44 so as to be movable in the YZ axis direction integrally with the spindle 22A. The microscope 23 is an imaging device having an imaging optical system and an image sensor (for example, a COMS (Complementary Metal Oxide Semiconductor) camera), although it is not shown in the figure. The microscope 23 may be composed of a high-magnification microscope and a low-magnification microscope with different imaging magnifications. The microscope 23 photographs the front surface of the workpiece W during the cutting process of the workpiece W. The image of the workpiece W taken by the microscope 23 is used for alignment between the workpiece W and the blades 21A and 21B.

[0037] Figure 3 is an enlarged front view of the white light interferometer 24 shown in Figure 2. As shown in Figure 3 and Figure 2 described above, the white light interferometer 24 is mounted on the Z carriage 44 integrally with the spindle 22B and is held so as to be movable in the YZ axis direction by the Y carriage 43 and the Z carriage 44. The white light interferometer 24 is used to measure the machining quality of grooves 25A and 25B (see Figures 6 and 7) formed in the workpiece W by the blades 21A and 21B. In addition, the white light interferometer 24 is vertically scanned (hereinafter simply referred to as vertical scanning) in the Z axis direction perpendicular to the table 31 (workpiece W) via the Z carriage 44 when measuring this machining quality.

[0038] The table 31 has a workpiece holding surface 31a formed in a porous manner, and this workpiece holding surface 31a holds the workpiece W by suction from its back side. The table 31 is held so as to be movable in the X-axis direction by the X carriage 36 described later, and is also held so as to be rotatable about the rotation axis CA by the rotation unit 37 described later.

[0039] The machining section 16 is provided with an X-base 32, an X-guide 34, an X-drive unit 35, an X-carriage 36, and a rotary unit 37. The X-base 32 has a flat plate shape extending in the X-axis direction, and the X-guide 34 is provided on its upper surface in the Z-axis direction. The X-guide 34 has a shape extending in the X-axis direction and guides the X-carriage 36 along the X-axis direction. The X-drive unit 35 uses an actuator such as a linear motor to move (drive) the X-carriage 36 in the X-axis direction along the X-guide 34.

[0040] The rotating unit 37 is provided on the upper surface of the X carriage 36. A table 31 is also provided on the upper surface of the rotating unit 37. The rotating unit 37 is rotationally driven by a rotational drive unit 38 (see Figure 5), which consists of a motor and gears. As a result, the rotating unit 37 rotates the table 31 in the θ direction about its rotation axis CA. The rotational drive unit 38 corresponds to the rotational drive mechanism of the present invention.

[0041] The workpiece W, transported from the load port 12 by the transport mechanism 14, is held by the table 31 through suction, and moves and rotates together with the table 31.

[0042] The machining section 16 is also provided with a Y-base 41, a Y-guide 42, a pair of Y-carriages 43, and a pair of Z-carriages 44. The Y-base 41 has a gate-like shape that straddles the X-base 32 in the Y-axis direction. A Y-guide 42 is provided on the X-axis side of the Y-base 41. The Y-guide 42 has a shape that extends in the Y-axis direction and guides the pair of Y-carriages 43 along the Y-axis direction. The pair of Y-carriages 43 are driven independently along the Y-guide 42 by a Y-drive unit 46 (see Figure 5), which is an actuator composed of, for example, a stepping motor and a ball screw.

[0043] Each of the pair of Y carriages 43 is provided with a Z carriage 44 that is movable in the Z-axis direction via a Z drive unit 48 (see Figure 5) which is composed of an actuator such as a stepping motor. One of the Z carriages 44 is equipped with a spindle 22A and a microscope 23, and the other Z carriage 44 is equipped with a spindle 22B and a white light interferometer 24.

[0044] By driving the X carriage 36, the rotating unit 37, each Y carriage 43, and each Z carriage 44, the blades 21A, 21B, the microscope 23, and the white light interferometer 24 can be moved relative to the table 31 and the workpiece W in the XYZ axis direction and the θ direction.

[0045] Figure 4 is a cross-sectional view of the white light interferometer 24. As shown in Figure 4, the white light interferometer 24 is a so-called Mirau-type white light interferometer and comprises a housing 50, a white light source 51, a first beam splitter 52, an objective lens 53, a glass plate 54, a second beam splitter 55, and an imaging unit 56.

[0046] The housing 50 houses the first beam splitter 52, the objective lens 53, the glass plate 54, and the second beam splitter 55. Within the housing 50, the second beam splitter 55, the glass plate 54, the objective lens 53, and the first beam splitter 52 are arranged from the lower side to the upper side in the Z-axis direction. A white light source 51 is mounted on the side of the housing 50 and on the side of the first beam splitter 52. Furthermore, an imaging unit 56 is mounted on the top surface of the housing 50 and above the first beam splitter 52.

[0047] The white light source 51 emits white light L1 (light mixed with light from various wavelength ranges of visible light) toward the first beam splitter 52 while the white light interferometer 24 is scanned vertically once (or multiple times). The first beam splitter 52 reflects a portion of the white light L1 incident from the white light source 51 toward the objective lens 53. The first beam splitter 52 also transmits a portion of the interference signal L4 incident from the objective lens 53 and emits this portion toward the imaging unit 56.

[0048] The objective lens 53 focuses the white light L1 incident from the first beam splitter 52 onto the focal point P of the workpiece W. The diameter of the focal point P (focused spot) is not particularly limited.

[0049] The glass plate 54 is equipped with a mirror 54a in its center that functions as a reference surface. The glass plate 54 (excluding the mirror 54a) transmits the white light L1 incident from the objective lens 53 directly and emits it towards the second beam splitter 55.

[0050] The second beam splitter 55 splits the white light L1 focused by the objective lens 53 into measurement light L2 and reference light L3. It transmits the measurement light L2 to the workpiece W and reflects the reference light L3 toward the mirror 54a. The measurement light L2 that irradiates the workpiece W is reflected by the workpiece W and incident on the second beam splitter 55. The reference light L3 reflected by the mirror 54a is incident on the second beam splitter 55 and a portion of it is reflected by the second beam splitter 55. This generates an interference signal L4 (interference light) between the measurement light L2 and the reference light L3. This interference signal L4 is incident on the imaging unit 56 via the glass plate 54, the objective lens 53, and the first beam splitter 52.

[0051] The optical path length of the reference light L3 is constant, but the optical path length of the measurement light L2 changes according to the vertical scanning of the white light interferometer 24. As is well known, when the difference in optical path lengths between the measurement light L2 and the reference light L3 is zero (including nearly zero), the interference between the measurement light L2 and the reference light L3 across all wavelength ranges of visible light reinforces each other, resulting in the maximum signal intensity of the interference signal L4 (see, for example, Japanese Patent Application Publication No. 2017-106860).

[0052] The imaging unit 56 is equipped with a two-dimensional image sensor of the CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) type, in which multiple pixels (photodetectors) are arranged in a two-dimensional array in the XY axis direction. While the white light interferometer 24 is performing one vertical scan (or multiple scans), the imaging unit 56 captures the interference signal L4 incident from the first beam splitter 52 for each pixel, thereby detecting (acquiring) the interference signal L4 for each pixel and outputting the interference signal L4 for each pixel to the control unit 60 (see Figure 5).

[0053] [Functions of the General Control Unit] Figure 5 is a functional block diagram of the central control unit 60 of the dicing apparatus 10 according to the first embodiment. As shown in Figure 5, the central control unit 60 includes an arithmetic circuit composed of various processors and memory. The various processors include CPUs (Central Processing Units), GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), and programmable logic devices [e.g., SPLDs (Simple Programmable Logic Devices), CPLDs (Complex Programmable Logic Devices), and FPGAs (Field Programmable Gate Arrays)]. The various functions of the central control unit 60 may be realized by a single processor, or by multiple processors of the same or different types.

[0054] In addition to the previously described spindles 22A, 22B, microscope 23, white light interferometer 24, X drive unit 35, rotation drive unit 38, Y drive unit 46, and Z drive unit 48, the control unit 60 is connected to an operation unit 62, a memory unit 64, a display unit 66, and the like.

[0055] The operation unit 62 uses a keyboard, mouse, control panel, and operation buttons to receive input from the operator for various operations. The storage unit 64 stores the control program (not shown) for the dicing device 10, as well as measurement results from the processing quality measurement unit 82, which will be described later. The display unit 66 uses various known monitors, such as a liquid crystal display. This display unit 66 displays the measurement results from the processing quality measurement unit 82, as well as various setting screens for the dicing device 10.

[0056] The integrated control unit 60 functions as the blade drive control unit 70, the movement control unit 72, the imaging control unit 74, the detection control unit 76, the processing control unit 78, the measurement control unit 80, the processing quality measurement unit 82, and the correction value determination unit 84 by executing a control program (not shown) stored in the memory unit 64. Note that the "~unit" in the integrated control unit 60 (and the server 200 described later) may also be referred to as a "~circuit," "~device," or "~equipment." In other words, the "~unit" may consist of firmware, software, hardware, or a combination thereof.

[0057] The blade drive control unit 70 controls the rotational drive of the blades 21A and 21B by the spindles 22A and 22B.

[0058] The movement control unit 72 drives a relative movement mechanism 49, which includes an X drive unit 35 (X carriage 36), a rotation drive unit 38 (rotation unit 37), a Y drive unit 46 (Y carriage 43), and a Z drive unit 48 (Z carriage 44), to move the blades 21A, 21B, the microscope 23, and the white light interferometer 24 relative to the table 31 and the workpiece W.

[0059] For example, before aligning the workpiece W with the blades 21A and 21B, the movement control unit 72 drives the relative movement mechanism 49 to adjust the position of the microscope 23 to a position where a predetermined alignment reference of the workpiece W can be photographed. The alignment reference here is a reference for the dicing device 10 to recognize the position of the street C (see Figure 6, etc., also called the planned division line) of the workpiece W, and for example, a recognition mark may be used.

[0060] Furthermore, when aligning the workpiece W with the blades 21A and 21B, the movement control unit 72 drives the relative movement mechanism 49 to align the blades 21A and 21B with the machining start position of the workpiece W.

[0061] Furthermore, when the workpiece W is being cut by the blades 21A and 21B, the movement control unit 72 drives the relative movement mechanism 49 to perform cutting feed of the workpiece W in the X direction, and index feed of the blades 21A and 21B in the Y direction and depth of cut feed in the Z direction.

[0062] Furthermore, when measuring the machining quality of grooves 25A and 25B (see Figures 6 and 7) formed in the workpiece W by blades 21A and 21B, the movement control unit 72 drives the relative movement mechanism 49 to perform position adjustment and vertical scanning of the white light interferometer 24. For this reason, the movement control unit 72 functions as a scanning control unit of the present invention.

[0063] The imaging control unit 74 controls the imaging of the workpiece W by the microscope 23. After the position adjustment of the microscope 23 as described above, the imaging control unit 74 causes the microscope 23 to take images of the workpiece W. As a result, the image of the workpiece W is output from the microscope 23 to the detection control unit 76.

[0064] The detection control unit 76 performs alignment detection by detecting the position of the workpiece W on street C (see Figures 6 and 7) based on the image of the workpiece W input from the microscope 23, using a known image recognition method to detect the alignment reference within the image. The detection control unit 76 then outputs the alignment detection result to the machining control unit 78.

[0065] Based on the alignment detection result from the detection control unit 76, the machining control unit 78 drives the spindles 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 to perform cutting with blades 21A, 21B for each street C (see Figure 6) of the workpiece W. Here, since the dicing device 10 in this embodiment is a so-called twin-spindle dicer, the machining control unit 78 selectively executes, for example, a meeting cutting method and a step cutting method as the cutting method for the workpiece W. The selection of the cutting method is performed by the operation unit 62.

[0066] Figure 6 is an explanatory diagram illustrating the meeting cutting method. As shown in Figure 6, in the meeting cutting method, blades 21A and 21B of the same shape (same thickness) are mounted on spindles 22A and 22B. Based on the alignment detection result by the detection control unit 76, the machining control unit 78 drives the spindles 22A and 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 to repeatedly perform simultaneous machining for each of the two streets C.

[0067] Simultaneous machining is a process in which two streets C are cut at once using two blades 21A and 21B of the same shape, simultaneously forming groove 25A with blade 21A and groove 25B with blade 21B. The grooves 25A and 25B formed by the meeting cutting method are so-called full-cut grooves with substantially the same shape. In the meeting cutting method, the cutting range of the workpiece W can be divided into two, and each range can be assigned to a different blade 21A and 21B, thereby shortening the machining time of the workpiece W.

[0068] Figure 7 is an explanatory diagram illustrating the step-cut method. Figure 8 is a cross-sectional view of a portion of the workpiece W cut using the step-cut method. As shown in Figures 7 and 8, the step-cut method is selected when the workpiece W is a laminate in which a low-dielectric constant insulating film (Low-k film) and a functional film that forms a circuit are laminated on the surface of a substrate such as silicon. In this step-cut method, blades 21A and 21B of different thicknesses (blades 21A and 21B of the same shape are also acceptable) are mounted on spindles 22A and 22B. Then, in the step-cut method, grooves 25A and 25B are formed for each street C by the blades 21A and 21B.

[0069] Specifically, the machining control unit 78 drives the spindles 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72, respectively, based on the alignment detection result from the detection control unit 76, and repeatedly executes the first machining process and the second machining process for each street C.

[0070] The first processing step involves cutting the street C with a wide blade 21A, for example, with a width of approximately 50 μm, to form a groove 25A (corresponding to the first groove of the present invention) of a predetermined depth along the street C. In the step-cut method, the groove 25A becomes a so-called half-cut groove. This removes the low-k film and the like on the street C.

[0071] The second machining process involves cutting the bottom of groove 25A with a narrow blade 21B, for example, with a width of approximately 30 μm, to form groove 25B. In the step-cut method, groove 25B becomes a so-called full-cut groove, which is narrower than groove 25A. This divides the workpiece W along the street C.

[0072] The measurement control unit 80 corresponds to the first measurement control unit of the present invention, and activates the movement control unit 72 and the white light interferometer 24 when measuring the processing quality of grooves 25A and 25B formed in the workpiece W by the blades 21A and 21B.

[0073] When the aforementioned meeting cutting method is selected, the measurement control unit 80 first drives the relative movement mechanism 49 via the movement control unit 72 to perform a position adjustment to move the white light interferometer 24 relative to the groove 25A of the workpiece W that is to be measured, so that the measurement light L2 can be irradiated onto it. Here, the positions of the grooves 25A and 25B formed in the workpiece W by the blades 21A and 21B are known. Therefore, the measurement control unit 80 drives the relative movement mechanism 49 to adjust the position of the white light interferometer 24 relative to the groove 25A based on the known position of the groove 25A. This eliminates the need to search for the groove 25A. However, if the groove 25A is located within the irradiation range (spot) of the measurement light L2 emitted from the white light interferometer 24 for reasons such as the spot diameter of the measurement light L2 emitted from the white light interferometer 24 being sufficiently large, this position adjustment may be omitted.

[0074] Next, the measurement control unit 80 operates the white light interferometer 24 (white light source 51 and imaging unit 56) at a position where the measurement light L2 can be irradiated onto the groove 25A. As a result, the measurement light L2 is irradiated onto the groove 25A from the white light interferometer 24, and the interference signal L4 for each pixel is output from the imaging unit 56. Furthermore, while the white light interferometer 24 is irradiating with measurement light L2 and outputting the interference signal L4 for each pixel, the measurement control unit 80 drives the relative movement mechanism 49 via the movement control unit 72 to vertically scan the white light interferometer 24.

[0075] Similarly, the measurement control unit 80 controls the movement control unit 72 and the white light interferometer 24 to perform positional adjustment of the white light interferometer 24 relative to the groove 25B, as well as operation and vertical scanning of the white light interferometer 24.

[0076] On the other hand, if the step-cut method described above is selected, the measurement control unit 80 controls the movement control unit 72 and the white light interferometer 24 to adjust the position of the white light interferometer 24 with respect to grooves 25A and 25B along the same street C, and to operate and vertically scan the white light interferometer 24.

[0077] The machining quality measurement unit 82 acquires interference signals L4 for one vertical scan per pixel of the imaging unit 56 from the white light interferometer 24 via a communication interface (not shown). As a result, when the aforementioned meeting cutting method is selected, the machining quality measurement unit 82 acquires the aforementioned interference signals L4 for one vertical scan per pixel (hereinafter simply abbreviated as "interference signal L5A") from the white light interferometer 24 for each groove 25A, 25B. Furthermore, when the aforementioned step-cut method is selected, the machining quality measurement unit 82 acquires the aforementioned interference signals L4 for one vertical scan per pixel (hereinafter simply abbreviated as "interference signal L5B") from the white light interferometer 24 that correspond to grooves 25A, 25B along the same street C.

[0078] The machining quality measurement unit 82 then performs a so-called kerf check to measure the machining quality (also called machining state) of the grooves 25A and 25B formed in the workpiece W, based on the interference signal L5A or L5B acquired from the white light interferometer 24. In the first embodiment, the machining quality of the grooves 25A and 25B refers to the machining position of the grooves 25A and 25B, i.e., the Y-axis position.

[0079] Figure 9 is an explanatory diagram illustrating the three-dimensional shape measurement of grooves 25A and 25B by the processing quality measurement unit 82. Figure 10 is an explanatory diagram illustrating the cross-sectional shape measurement of grooves 25A and 25B along the Y-axis direction by the processing quality measurement unit 82. In Figures 9 and 10, the shape measurement (kerf check) of grooves 25A and 25B formed by the step-cut method described in Figure 7, etc., is used as an example for explanation.

[0080] As shown in Figures 9, 10, and Figure 5 described above, the machining quality measurement unit 82 calculates the height of each pixel of the imaging unit 56 based on the interference signal L5B, that is, the height in the Z-axis direction of the corresponding position on the workpiece W (inner surfaces of grooves 25A and 25B, and the outer surface of workpiece W) corresponding to each pixel. Since this method of calculating the height position is a known technique, a detailed explanation is omitted here. As a result, the machining quality measurement unit 82 can generate three-dimensional shape information 86 showing the three-dimensional shape of grooves 25A and 25B as shown in Figure 9. The machining quality measurement unit 82 can also generate cross-sectional shape information 88 showing the cross-sectional shape of grooves 25A and 25B along the Y-axis direction as shown in Figure 10.

[0081] Furthermore, the positional relationship between the workpiece W and the white light interferometer 24 is known based on the alignment detection result by the detection control unit 76. Therefore, the processing quality measurement unit 82 can simultaneously calculate the positional coordinates in the XY axis direction of the corresponding position on the workpiece W corresponding to each pixel of the imaging unit 56 (hereinafter abbreviated as workpiece corresponding position coordinates) based on the positional coordinates of the white light interferometer 24 in the XY axis direction during vertical scanning. As a result, the processing positions of the grooves 25A and 25B within the workpiece W can be individually determined based on at least one of the three-dimensional shape information 86 and the cross-sectional shape information 88, and the workpiece corresponding position coordinates.

[0082] Figure 11 is an explanatory diagram illustrating an example of kerf checking of grooves 25A and 25B formed by a step-cut method, that is, measuring the machining position of grooves 25A and 25B within the workpiece W. As shown in Figure 11, the machining quality measurement unit 82 calculates the groove center position CL1 in the Y-axis direction of groove 25A within the workpiece W, and the groove center position CL2 in the Y-axis direction of groove 25B, based on at least one of the three-dimensional shape information 86 and the cross-sectional shape information 88, and the workpiece corresponding position coordinates. Groove center position CL1 corresponds to the machining position of groove 25A, and groove center position CL2 corresponds to the machining position of groove 25B.

[0083] The machining quality measurement unit 82 then outputs the measurement results of the machining position of groove 25A (groove center position CL1) and the machining position of groove 25B (groove center position CL2) to the correction value determination unit 84, the storage unit 64, and the display unit 66. As a result, the measurement results of the machining positions of grooves 25A and 25B are stored in the storage unit 64 and displayed in the display unit 66.

[0084] Figure 12 is an explanatory diagram illustrating the determination of correction values ​​Δy1 and Δy2 for the machining positions of grooves 25A and 25B formed by the step-cut method using the correction value determination unit 84.

[0085] As shown in Figure 12 and Figure 5 described above, the correction value determination unit 84 determines a correction value Δy1 that corrects the machining position of groove 25A by blade 21A in the Y-axis direction, and a correction value Δy2 that corrects the machining position of groove 25B by blade 21B in the Y-axis direction.

[0086] Specifically, the correction value determination unit 84 has pre-set target values ​​for the machining positions of grooves 25A and 25B corresponding to the type of workpiece W, for example, the Y-axis position of street C within the workpiece W. Based on this, the correction value determination unit 84 determines the correction value Δy1 based on the measurement result of the machining position of groove 25A (groove center position CL1) by the machining quality measurement unit 82 and the target value of the machining position of groove 25A. The correction value determination unit 84 also determines the correction value Δy2 based on the measurement result of the machining position of groove 25B (groove center position CL2) by the machining quality measurement unit 82 and the target value of the machining position of groove 25B.

[0087] The correction value determination unit 84 then outputs the determined correction values ​​Δy1 and Δy2 to the machining control unit 78 described above. Based on the correction values ​​Δy1 and Δy2 input from the correction value determination unit 84, the machining control unit 78 corrects the machining position (Y-axis position) of the grooves 25A and 25B that are formed in the new street C of the workpiece W by the blades 21A and 21B.

[0088] The method for measuring the machining position (machining quality) of grooves 25A and 25B formed by the meeting cutting method, and the method for determining the correction values ​​Δy1 and Δy2, are basically the same as those for the step cutting method described above. In this case, the machining quality measurement unit 82 measures the machining position (groove center positions CL1 and CL2) for each groove 25A and 25B based on the interference signal L5A, and the correction value determination unit 84 determines the correction values ​​Δy1 and Δy2 based on the measurement results.

[0089] [Operation of the First Embodiment] Figure 13 is a flowchart showing the flow of the cutting process of a workpiece W by the dicing apparatus 10 of the first embodiment, which corresponds to the control method of the workpiece processing apparatus of the present invention, and in particular the flow of the measurement process of the processing quality (processing position) of grooves 25A and 25B.

[0090] As shown in Figure 13, when the workpiece W is held by suction on the table 31, the movement control unit 72, the image capture control unit 74, and the detection control unit 76 of the overall control unit 60 are activated. As a result, the movement control unit 72 drives the relative movement mechanism 49 to adjust the position of the microscope 23, and after this position adjustment, the microscope 23 captures an alignment reference of the workpiece W under the control of the image capture control unit 74, and furthermore, the detection control unit 76 performs alignment detection based on the image of the alignment reference captured by the microscope 23 (step S1).

[0091] Once alignment detection is complete, the movement control unit 72 drives the relative movement mechanism 49 based on the alignment detection results to align the street C of the workpiece with the blades 21A and 21B.

[0092] Next, the machining control unit 78 drives each spindle 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 to cut the street C with the blades 21A, 21B using either a meeting cutting method (see Figure 6) or a step cutting method (see Figure 7) (step S2). This forms grooves 25A, 25B along the street C. Step S2 is then repeated until measurement of the machining quality (in this case, machining position) of the grooves 25A, 25B is started (NO in step S3). Alternatively, after forming the first grooves 25A, 25B, the process may proceed immediately to step S4.

[0093] When measuring the machining quality of grooves 25A and 25B is initiated (YES in step S3), the measurement control unit 80 first drives the relative movement mechanism 49 via the movement control unit 72 based on the known positions of grooves 25A and 25B to adjust the position of the white light interferometer 24 to a position where measurement light L2 can be irradiated onto grooves 25A and 25B (step S4). This allows for quick adjustment of the position of the white light interferometer 24. After this adjustment, the measurement control unit 80 activates the white light interferometer 24 (step S5). As a result, measurement light L2 is irradiated onto grooves 25A and 25B from the white light interferometer 24, and the interference signal L4 for each pixel is output from the imaging unit 56 to the machining quality measurement unit 82.

[0094] Furthermore, while the white light interferometer 24 is irradiating with measurement light L2 and outputting interference signal L4, the measurement control unit 80 drives the relative movement mechanism 49 via the movement control unit 72 to vertically scan the white light interferometer 24 (step S6, corresponding to the scanning control step of the present invention). As a result, the processing quality measurement unit 82 acquires interference signal L5A (meeting cutting method) or interference signal L5B (step cutting method) (step S7).

[0095] Then, the processing quality measurement unit 82 generates either three-dimensional shape information 86 or cross-sectional shape information 88 of the grooves 25A and 25B, as shown in Figures 9 and 10, based on the interference signal L5A or L5B acquired from the white light interferometer 24. In addition, the processing quality measurement unit 82 calculates the workpiece corresponding position coordinates based on the alignment detection result by the detection control unit 76 and the position coordinates of the white light interferometer 24 in the XY axis direction during vertical scanning.

[0096] Next, the machining quality measurement unit 82 calculates the machining position (groove center positions CL1, CL2) of grooves 25A and 25B as the machining quality of grooves 25A and 25B, as shown in Figure 11, based on at least one of the three-dimensional shape information 86 and the cross-sectional shape information 88 and the workpiece corresponding position coordinates. This completes the measurement (kerf check) of the machining position of grooves 25A and 25B (step S8, corresponding to the machining quality measurement step of the present invention). The machining quality measurement unit 82 then outputs the measurement results of the machining position of grooves 25A and 25B to the correction value determination unit 84, the storage unit 64, and the display unit 66.

[0097] As described above, in this embodiment, the cross-sectional shape of grooves 25A and 25B can be obtained using the white light interferometer 24. Therefore, the processing position (processing quality) of grooves 25A and 25B can be measured without analyzing images of grooves 25A and 25B taken by the microscope 23, as in the conventional method. This makes it possible to accurately measure the processing position of groove 25B even when groove 25B is formed at the bottom of groove 25A, such as in a step-cut method, that is, when it is difficult to determine the processing position of groove 25B based on images taken by the microscope 23.

[0098] Furthermore, in this embodiment, a kerf check of the groove 25B formed by the actual step-cut method can be performed without performing a so-called step-kerf check, which involves forming a groove 25B with a narrow blade 21B on the uncut portion of the workpiece W as shown in Figure 35. Therefore, the machining position of the groove 25B can be measured with high accuracy.

[0099] Once the measurement of the machining positions of grooves 25A and 25B (kerf check) is complete, the correction value determination unit 84 determines the correction values ​​Δy1 and Δy2 for the machining positions of each groove 25A and 25B based on the measurement results of the machining positions of grooves 25A and 25B (groove center positions CL1 and CL2) and the target values ​​of those machining positions (step S9). Next, the correction value determination unit 84 outputs the determination results of the correction values ​​Δy1 and Δy2 to the machining control unit 78.

[0100] Then, the machining control unit 78 drives the spindles 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 based on the correction values ​​Δy1 and Δy2 to perform cutting of the next and subsequent streets C using either a meeting cutting method or a step cutting method (step S100). As a result, for each blade 21A, 21B, cutting can be performed at a position shifted by the correction values ​​Δy1 and Δy2 in the Y-axis direction from the target position (design position) of the next and subsequent streets C. As a result, grooves 25A and 25B can be formed with high precision along the next and subsequent streets C.

[0101] [Effects of the First Embodiment] As described above, in the dicing apparatus 10 of the first embodiment, the cross-sectional shape of grooves 25A and 25B can be accurately measured using the white light interferometer 24, and the processing position (processing quality) of grooves 25A and 25B can be accurately measured based on the measurement results of this cross-sectional shape. In particular, even when groove 25B is formed at the bottom of groove 25A, as in the step-cut method, the processing position (processing quality) of groove 25B can be accurately measured.

[0102] Furthermore, in the first embodiment, vertical scanning of the white light interferometer 24 can be performed using the relative movement mechanism 49 of the blade 21B (Z carriage 44 and Z drive unit 48), eliminating the need to provide a separate dedicated scanning mechanism and thus reducing costs. Moreover, in the first embodiment, by integrally mounting the blade 21B and the white light interferometer 24 on the Z carriage 44, the position adjustment of the white light interferometer 24 relative to the grooves 25A and 25B (workpiece) of the workpiece W can be performed using a conventional alignment detection method.

[0103] [Second Embodiment] Figure 14 is an explanatory diagram illustrating the cutting of a workpiece W by a dicing device 10 of the second embodiment and the back surface grinding of a workpiece W by a grinding (polishing) device (not shown). In the first embodiment described above, each street C is completely cut (separated) by the cutting of the workpiece W by the dicing device 10. In contrast, as shown by the reference numeral XIVA in Figure 14, in the cutting of the workpiece W by the dicing device 10 of the second embodiment, the blades 21A and 21B do not completely cut each street C, but instead perform a so-called half-cut, leaving a certain amount of each street C uncut, thereby forming half-cut grooves 90A and 90B (corresponding to the workpiece portion). The half-cut groove 90A formed by blade 21A and the half-cut groove 90B formed by blade 21B are substantially the same shape.

[0104] Then, as shown by the symbol XIVB in Figure 14, the back surface of the workpiece W is ground using a grinding device separate from the dicing device 10 to remove any remaining material, thereby completely cutting each street C as shown by the symbol XIVC in Figure 14.

[0105] When the dicing device 10 performs a half-cut of each street C in this manner, if the machining depth (also called the cutting depth or cutting depth) of street C by blades 21A and 21B is insufficient, even if the back surface of the workpiece W is ground, the workpiece W cannot be cut, resulting in a cutting defect. Conversely, if street C is cut too deeply by blades 21A and 21B, the workpiece W will crack before the back surface is ground. Therefore, if the accuracy of the cutting depth of blades 21A and 21B is low, the yield will deteriorate, especially in the production of thin devices (machining of thin workpieces W).

[0106] Furthermore, the diameter of blades 21A and 21B changes due to wear, and their height in the Z-axis direction changes due to temperature changes. Therefore, high-precision control of the machining depth in the Z-axis direction of blades 21A and 21B for each street C (workpiece W) is important.

[0107] Figure 15 is an explanatory diagram illustrating a chop cutter set (see, for example, Japanese Patent Publication No. 2017-164843), which is an example of a conventional method for adjusting the machining depth of blades 21A and 21B. As shown in Figure 15, in the chop cutter set, a dummy workpiece WA is placed near the workpiece W held on the table 31, and the relative height between the dummy workpiece WA and the workpiece W is measured with a high-precision sensor (such as an air microgauge). Then, the blades 21A and 21B perform a chop cut (chop processing) on ​​the dummy workpiece WA to form a chop cut mark 92 (kerf).

[0108] Then, based on the images captured by the microscope 23 of the chop cut marks 92 formed on each blade 21A and 21B, the length cx of each chop cut mark 92 is measured. Next, the machining depth of blades 21A and 21B is calculated based on the length cx of each chop cut mark 92 and the known diameters of blades 21A and 21B, and the machining depth of blades 21A and 21B is corrected (adjusted) based on this calculation result.

[0109] However, this chop cutter set has the following two problems. The first problem is that the chop cutter set does not directly measure the machining depth of each chop cut mark 92, so minute errors between the chop cutter set and the actual cutting process cumulatively affect the accuracy of the machining depth of blades 21A and 21B. In this case, if the error in the machining depth of blades 21A and 21B is repeatable, it can be fixedly corrected, but if there is variation in the error, it will negatively affect the absolute accuracy of the machining depth of blades 21A and 21B (the correction limit will be lowered).

[0110] The second problem is that the chop cutter set does not cut the actual workpiece W with blades 21A and 21B, and therefore does not measure the machining depth of the half-cut grooves 90A and 90B formed on the actual workpiece W. For this reason, in order to feed back the correction value for the machining depth of blades 21A and 21B to the dicing device 10, it was necessary to chop-cut another dummy workpiece WA after the machining of workpiece W was completed, and to input the result of measuring the length cx with a separate inspection device into the dicing device 10.

[0111] Therefore, in the dicing apparatus 10 of the second embodiment, the machining depths cz1 and cz2 (see Figure 16) of the half-cut grooves 90A and 90B formed in the workpiece W are measured using a white light interferometer 24. In the second embodiment, the machining widths cy1 and cy2 of the half-cut grooves 90A and 90B are also measured simultaneously with the machining depths cz1 and cz2. Here, the machining widths cy1 and cy2 and machining depths cz1 and cz2 of the half-cut grooves 90A and 90B correspond to the machining quality (machined shape) of the workpiece in the present invention.

[0112] Since the dicing apparatus 10 of the second embodiment has basically the same configuration as the dicing apparatus 10 of the first embodiment, parts that are functionally or structurally identical to those of the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0113] In the second embodiment, the machining control unit 78 drives each spindle 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 to cut each street C of the workpiece W by simultaneous machining with blades 21A, 21B using a meeting cutting method. As a result, half-cut grooves 90A, 90B are formed for every two streets C.

[0114] In the second embodiment, the measurement control unit 80 controls the white light interferometer 24 and the relative movement mechanism 49 to perform position adjustment of the white light interferometer 24, operation of the white light interferometer 24, and vertical scanning for each half-cut groove 90A, 90B. As a result, the processing quality measurement unit 82 of the second embodiment acquires interference signals L5A from the imaging unit 56 for each half-cut groove 90A, 90B.

[0115] Figure 16 is an explanatory diagram illustrating the measurement of the cross-sectional shape of the half-cut grooves 90A and 90B along the Y-axis direction by the machining quality measurement unit 82 of the second embodiment. As shown in Figure 16, the machining quality measurement unit 82 of the second embodiment generates cross-sectional shape information 88 of the half-cut grooves 90A and 90B based on the interference signal L5A for each half-cut groove 90A and 90B acquired from the white light interferometer 24, similar to the first embodiment.

[0116] Next, the machining quality measurement unit 82 calculates the machining width cy1 and machining depth cz1 of the half-cut groove 90A and 90B, as well as the machining width cy2 and machining depth cz2 of the half-cut groove 90B, based on the cross-sectional shape information 88 of the half-cut grooves 90A and 90B, as the machining quality (machining shape) of the half-cut grooves 90A and 90B. Here, the machining depths cz1 and cz2 are the depths in the Z-axis direction of the half-cut grooves 90A and 90B at the center positions of the machining widths cy1 and cy2, respectively. Alternatively, the machining depths cz1 and cz2 may be defined as the depth to the lowest point in the Z-axis direction of the half-cut grooves 90A and 90B. The machining quality measurement unit 82 then outputs the measurement results of the machining depths cz1 and cz2 for each half-cut groove 90A and 90B to the correction value determination unit 84, the storage unit 64, and the display unit 66.

[0117] In the second embodiment, the correction value determination unit 84 determines a correction value Δz1 for the machining depth cz1 corresponding to the blade 21A and a correction value Δz2 for the machining depth cz2 corresponding to the blade 21B, based on the measurement results of the machining depth cz1 and cz2 by the machining quality measurement unit 82 and the target values ​​tz for the machining depth cz1 and cz2 of the half-cut grooves 90A and 90B corresponding to the type of workpiece W.

[0118] Furthermore, the correction value determination unit 84 outputs the determined correction values ​​Δz1 and Δz2 to the machining control unit 78. Based on the correction values ​​Δz1 and Δz2 input from the correction value determination unit 84, the machining control unit 78 controls the relative movement mechanism 49 and the like to correct the machining depths cz1 and cz2 of the half-cut grooves 90A and 90B formed in the new street C of the workpiece W by the blades 21A and 21B.

[0119] Furthermore, the cutting process of the workpiece W by the dicing device 10 in the second embodiment, and in particular the measurement process of the machining quality (machining depth cz1, cz2) of the half-cut grooves 90A and 90B, are basically the same as the cutting process of the first embodiment shown in Figure 13, so a detailed explanation will be omitted here.

[0120] As described above, in the dicing apparatus 10 of the second embodiment, the cross-sectional shape of the half-cut grooves 90A and 90B can be accurately measured using the white light interferometer 24, and based on these measurement results, the machining depth cz1 and cz2 (machining quality) can be accurately measured. Furthermore, since the machining depth cz1 and cz2 can be measured during the cutting process of the workpiece W by the blades 21A and 21B, accurate correction values ​​Δz1 and Δz2 can be immediately applied to the cutting process of subsequent streets C. In addition, since the correction values ​​Δz1 and Δz2 can be determined each time the cutting process of one line of street C is performed, the machining accuracy of the machining depth cz1 and cz2 for each blade 21A and 21B can be further improved.

[0121] [Third Embodiment] Figure 17 is an explanatory diagram illustrating the workpiece W after the formation of laser-processed grooves 94 by a laser processing device (not shown) and the cutting process of the workpiece W by the dicing device 10 of the third embodiment. In the first embodiment described above, when the workpiece W is a laminate in which a low-k film or the like is laminated on a silicon substrate, the dicing device 10 performs cutting using a step-cut method to form grooves 25A and 25B for each street C (see Figure 7).

[0122] In contrast, as shown by the labels XVIIA and XVIIB in Figure 17, in the third embodiment, the workpiece W is subjected to laser processing with laser light for each street C using a laser processing device (not shown) in advance. This removes the Low-k film by forming laser-processed grooves 94 (laser grooves, corresponding to the first groove) for each street C.

[0123] Next, in the third embodiment, the dicing device 10 forms grooves 25B (corresponding to the second groove) shown in Figure 7 at the bottom of each laser-processed groove 94 of the workpiece W, thereby completely cutting through the street C. By removing the brittle and difficult-to-process Low-k film with laser processing, the processing stability of the workpiece W by the dicing device 10 is improved.

[0124] Here, the groove 25B is formed based on the position of street C, or based on the center position of the machining width cy in the Y-axis direction of the laser-machined groove 94. In the latter case, conventionally, the laser-machined groove 94 of the workpiece W is photographed using a microscope 23, and the center position of the machining width cy is determined based on the image taken by this microscope 23.

[0125] However, the laser-processed groove 94 may have a rough, black appearance, and the edges 94a on both sides of the laser-processed groove 94 may be raised. In this case, even if the image of the laser-processed groove 94 taken with a microscope 23 is analyzed, it is difficult to distinguish between the processing width cy of the laser-processed groove 94 and the processing width gy of the laser-processed groove 94 including the edges 94a. For this reason, the measurement accuracy of the center position of the processing width cy varies in the conventional method, which negatively affects the processing accuracy of the groove 25B.

[0126] Therefore, in the dicing apparatus 10 of the third embodiment, a white light interferometer 24 is used to measure the center position of the processing width cy, which is the processing position of the laser-processed groove 94 that has been pre-formed in the workpiece W (processing quality of the first groove).

[0127] Since the dicing apparatus 10 of the third embodiment has basically the same configuration as the dicing apparatus 10 of the first embodiment, parts that are functionally or structurally identical to those of the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0128] The measurement control unit 80 of the third embodiment corresponds to the second measurement control unit of the present invention. Before the cutting process of the workpiece W by the blades 21A and 21B, this measurement control unit 80 controls the white light interferometer 24 and the relative movement mechanism 49 to adjust the position of the white light interferometer 24 relative to the laser processing groove 94, and repeatedly performs operation and vertical scanning of the white light interferometer 24 for each laser processing groove 94. As a result, the processing quality measurement unit 82 of the third embodiment acquires an interference signal L5A for each laser processing groove 94 from the imaging unit 56.

[0129] Figure 18 is an explanatory diagram illustrating the measurement of the three-dimensional shape of the laser-processed groove 94 by the processing quality measurement unit 82 of the third embodiment. Figure 19 is an explanatory diagram illustrating the measurement of the cross-sectional shape of the laser-processed groove 94 along the Y-axis direction by the processing quality measurement unit 82 of the third embodiment.

[0130] As shown in Figures 18 and 19, the processing quality measurement unit 82 of the third embodiment generates at least one of three-dimensional shape information 86 and cross-sectional shape information 88 for each laser-processed groove 94 based on the interference signal L5A for each laser-processed groove 94 acquired from the white light interferometer 24, similar to the first embodiment.

[0131] Next, the processing quality measurement unit 82 measures the processing width cy and its center position for each laser-processed groove 94 based on at least one of the three-dimensional shape information 86 and cross-sectional shape information 88 for each laser-processed groove 94, and the position coordinates in the XY axis direction of the corresponding position of the workpiece W corresponding to each pixel of the imaging unit 56. The processing quality measurement unit 82 then outputs the measurement result of the center position of the processing width cy for each laser-processed groove 94 to the processing control unit 78, the storage unit 64, and the display unit 66.

[0132] In the third embodiment, the processing control unit 78 drives each spindle 22A, 22B and relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 based on the measurement result of the center position of the processing width cy for each laser processing groove 94, and cuts the bottom of each laser processing groove 94 by simultaneous processing with blades 21A, 21B using a meeting cutting method. As a result, grooves 25A, 25B, which are full-cut grooves, are formed for each laser processing groove 94.

[0133] In addition, the flow of the measurement process for the processing quality (center position of the processing width cy) of the laser-processed groove 94 of the workpiece W by the dicing device 10 in the third embodiment, and the flow of the cutting process for grooves 25A and 25B are basically the same as the flow from step S3 onwards of the cutting process in the first embodiment shown in Figure 13 described above. However, in the third embodiment, step S9 is omitted, and in step S10, cutting of grooves 25A and 25B is performed by blades 21A and 21B based on the measurement result of the center position of the processing width cy for each laser-processed groove 94.

[0134] As described above, in the dicing apparatus 10 of the third embodiment, the cross-sectional shape of each laser-processed groove 94 can be accurately measured using the white light interferometer 24. Based on these measurement results, the processing width cy and its center position (processing quality) of each laser-processed groove 94 can be accurately measured. As a result, the processing accuracy of grooves 25A and 25B within the laser-processed groove 94 can be improved by the dicing apparatus 10.

[0135] [Fourth Embodiment] In each of the above embodiments, the machining quality of various grooves such as grooves 25A, 25B, half-cut grooves 90A, 90B, and laser-cut groove 94 is measured, and the cutting of the workpiece W by blades 21A, 21B is corrected based on these measurement results. In contrast, in the fourth embodiment, the tip shape of blades 21A, 21B is measured based on the measurement results of the machining quality of various grooves by blades 21A, 21B.

[0136] Figure 20 is an explanatory diagram illustrating the tip shapes of blades 21A and 21B. As shown in Figure 20, the tip shape of blades 21A and 21B (the cross-sectional shape of the outer circumference of the blade along the radial direction) is ideally rectangular, as shown by symbol XXA, meaning that the edges E1 and E2 formed by the outer circumference (tip surface) and the side surface of blades 21A and 21B are sharp. However, in reality, the edges E1 and E2 are rounded, as shown by symbol XXB. Normally, the workpiece W is cut using blades 21A and 21B shown by symbol XXB, but abnormal wear (such as uneven wear) may occur on blades 21A and 21B, as shown by symbol XXC.

[0137] Figure 21 is an explanatory diagram illustrating the problems that arise when cutting a workpiece W with unevenly worn blades 21A and 21B. As shown in Figure 21, when blades 21A and 21B are unevenly worn, the way edge E1 and edge E2 of blades 21A and 21B contact the workpiece W becomes different from each other. As a result, the quality of the ends of the grooves 25A and 25B (half-cut grooves 90A and 90B) formed by edges E1 and E2 becomes different from each other. Therefore, it is important to measure the tip shape of blades 21A and 21B to determine the uneven wear state of blades 21A and 21B.

[0138] Figure 22 is an explanatory diagram illustrating the measurement of the tip shape of conventional blades 21A and 21B. As shown in Figure 22, conventionally, as described in the second embodiment above, chop cut marks 92 are formed on the workpiece W etc. by blades 21A and 21B, and the chop cut marks 92 for each blade 21A and 21B are photographed with a microscope 23. Then, the cross-sectional shape of the tip portion 92a of each chop cut mark 92 is measured based on the photographed image of each chop cut mark 92. Subsequently, the uneven wear state of blades 21A and 21B is determined by measuring the tip shape of blades 21A and 21B based on the cross-sectional shape of the tip portion 92a of each blade 21A and 21B. Note that the symbol XXIIA indicates a chop cut mark 92 formed by a normal blade 21A or 21B, and the symbol XXIIB indicates a chop cut mark 92 formed by an unevenly worn blade 21A or 21B.

[0139] However, when measuring the tip shape of blades 21A and 21B based on images of chop cut marks 92, the following three problems arise. The first problem is that the tip shape of blades 21A and 21B can only be measured by the shape of the tip portion 92a of the chop cut mark 92, so the uneven wear state of blades 21A and 21B cannot be determined unless the amount of uneven wear on blades 21A and 21B becomes sufficiently large. As a result, there is a risk that the processing quality of the workpiece W by blades 21A and 21B will fall below the acceptable level, resulting in defects.

[0140] The second problem is that, because the cutting process of the workpiece W needs to be temporarily interrupted during the cutting process to form and photograph the chop cut marks 92, the productivity of the cutting process of the workpiece W by the dicing device 10 is reduced.

[0141] Figure 23 is an explanatory diagram illustrating the third problem. As shown by the symbol XXIIIA in Figure 23, the third problem is that when the tip portion 92a is photographed by the microscope 23, if reflections such as stray light occur at the tip portion 92a, overexposure occurs in the tip portion image 93, which is the image of the tip portion 92a taken by the microscope 23. As a result, the tip portion image 93 does not accurately reflect the cross-sectional shape of the tip portion 92a, and as shown by the symbol XXIIIB in Figure 23, it is not possible to accurately measure the cross-sectional shape information 88A along the Y-axis of the chop cut marks 92 based on the tip portion image 93. Therefore, it becomes impossible to accurately measure the tip shapes of the blades 21A and 21B.

[0142] Therefore, in the dicing apparatus 10 of the fourth embodiment, the cross-sectional shape (processing quality) of the half-cut grooves 90A and 90B is measured using a white light interferometer 24 during the cutting process of the workpiece W, and the tip shape of the blades 21A and 21B is measured based on this cross-sectional shape.

[0143] Figure 24 is a functional block diagram of the central control unit 60 of the dicing apparatus 10 of the fourth embodiment. The dicing apparatus 10 of the fourth embodiment has basically the same configuration as the dicing apparatus 10 of each of the above embodiments, except that the central control unit 60 functions as a blade shape measuring unit 100 instead of a correction value determination unit 84. For this reason, components that are functionally or structurally identical to those in each of the above embodiments are denoted by the same reference numerals and their descriptions are omitted.

[0144] In the fourth embodiment, the machining control unit 78 drives each spindle 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72, similar to the second embodiment, to form half-cut grooves 90A, 90B (see Figure 14) for each street C.

[0145] In the fourth embodiment, the measurement control unit 80 controls the white light interferometer 24 and the relative movement mechanism 49, similar to the second embodiment, to perform position adjustment of the white light interferometer 24, operation of the white light interferometer 24, and vertical scanning for each half-cut groove 90A, 90B. As a result, the processing quality measurement unit 82 of the fourth embodiment acquires an interference signal L5A from the white light interferometer 24 for each half-cut groove 90A, 90B.

[0146] Figure 25 is an explanatory diagram illustrating the calculation results of the cross-sectional shape along the Y-axis direction of the half-cut grooves 90A and 90B by the machining quality measurement unit 82 of the fourth embodiment. As shown in Figure 25 and Figure 24 described above, the machining quality measurement unit 82 of the fourth embodiment generates cross-sectional shape information 88 for each half-cut groove 90A and 90B based on the interference signal L5A for each half-cut groove 90A and 90B acquired from the white light interferometer 24, similar to the second embodiment. The machining quality measurement unit 82 then outputs the measurement results (cross-sectional shape information 88), which represent the machining quality of each half-cut groove 90A and 90B, to the blade shape measurement unit 100.

[0147] The blade shape measuring unit 100 measures the tip shapes of blades 21A and 21B based on the measurement results (cross-sectional shape information 88) of the cross-sectional shape of each half-cut groove 90A and 90B input from the processing quality measuring unit 82. Since the tip shapes of blades 21A and 21B are transferred to the bottom of the half-cut grooves 90A and 90B, the tip shapes of blades 21A and 21B can be measured from the cross-sectional shapes of the half-cut grooves 90A and 90B. The measurement results of the tip shapes of blades 21A and 21B by the blade shape measuring unit 100 are stored in the storage unit 64 and displayed in the display unit 66.

[0148] [Operation of the fourth embodiment] Figure 26 is a flowchart showing the flow of the measurement process for the tip shapes of blades 21A and 21B by the dicing device 10 of the fourth embodiment, which corresponds to the control method of the workpiece processing device of the present invention. As shown in Figure 26, similar to the first embodiment (see Figure 13), alignment detection (step S1) and cutting of each street C using the meeting cutting method (step S2) are performed, and half-cut grooves 90A and 90B are formed along each street C.

[0149] When measurement of the tip shape of blades 21A and 21B is initiated (YES in step S3A), the processes from step S4 to step S7 are executed in the same manner as in the first embodiment described above. Specifically, for each half-cut groove 90A and 90B, the following are performed: position adjustment of the white light interferometer 24 (step S4), operation and vertical scanning of the white light interferometer 24 (steps S5 and S6), and acquisition of the interference signal L5A by the processing quality measurement unit 82 (step S7).

[0150] Next, the processing quality measurement unit 82 generates cross-sectional shape information 88 for each half-cut groove 90A, 90B based on the interference signal L5A for each half-cut groove 90A, 90B acquired from the white light interferometer 24. This allows for accurate measurement of the cross-sectional shape of the half-cut grooves 90A, 90B without the formation of chop-cut marks 92 or imaging of the chop-cut marks 92 using a microscope 23 (step S11). The processing quality measurement unit 82 then outputs the cross-sectional shape information 88 for each half-cut groove 90A, 90B to the blade shape measurement unit 100.

[0151] The blade shape measuring unit 100, having received cross-sectional shape information 88 for each half-cut groove 90A, 90B, measures the tip shape of blades 21A, 21B based on each cross-sectional shape information 88 (step S12, corresponding to the blade shape measurement step of the present invention). The blade shape measuring unit 100 then outputs the measurement results of the tip shapes of blades 21A, 21B to the storage unit 64 and the display unit 66. As a result, the measurement results of the tip shapes of blades 21A, 21B are stored in the storage unit 64 and displayed in the display unit 66.

[0152] The operator determines the wear condition of each blade 21A and 21B based on the measurement results of the tip shapes of the blades 21A and 21B displayed on the display unit 66, and determines whether or not replacement of the blades 21A and 21B is necessary. Alternatively, the wear condition of each blade 21A and 21B, and the determination of whether or not replacement is necessary, may be performed automatically by the central control unit 60.

[0153] As described above, in the dicing apparatus 10 of the fourth embodiment, the cross-sectional shape of the half-cut grooves 90A and 90B can be accurately measured using the white light interferometer 24, and based on this measurement result, the tip shape of the blades 21A and 21B can be accurately measured. As a result, the uneven wear state of the tip shape of the blades 21A and 21B and its progression can be accurately determined. This allows the operator to be prompted to replace the blades 21A and 21B, or to truing (shape correction of the blades 21A and 21B), or dressing (sharpening and resharpening the blades 21A and 21B) before the processing quality of the workpiece W falls below the acceptable level and defects occur.

[0154] Furthermore, in the dicing apparatus 10 of the fourth embodiment, the tip shape of the blades 21A and 21B can be measured during the cutting process of the workpiece W by the blades 21A and 21B without forming and photographing the chop cut marks 92. As a result, the productivity of the dicing apparatus 10 can be improved compared to the conventional model.

[0155] In the fourth embodiment described above, half-cut grooves 90A and 90B are formed in each street C by simultaneous machining using blades 21A and 21B. However, grooves 25A and 25B (meeting cutting method), which are full-cut grooves as described in the first embodiment and the like, may also be formed. Even in this case, if the uneven wear of blades 21A and 21B progresses, the uneven wear state of the tip shape of blades 21A and 21B can be determined based on the cross-sectional shape of each groove 25A and 25B (cross-sectional shape information 88).

[0156] [Fifth Embodiment] Figure 27 is an explanatory diagram illustrating the problems that arise from back surface grinding of the workpiece W after the formation of the half-cut grooves 90A and 90B described in the second and fourth embodiments.

[0157] As shown by the symbol XXVIIA in Figure 27, the edge portion 110, which is the outer circumference of the workpiece W, has a shape that protrudes convexly in the radial direction of the workpiece W. Therefore, if the back surface of the workpiece W is ground after forming half-cut grooves 90A and 90B (not shown in Figure 27) for each street C of the workpiece W, the edge portion 110 becomes thin and sharply angled, as shown by the symbol XXVIIB in Figure 27. As a result, a problem arises in which cracks are likely to occur starting from this edge portion 110.

[0158] Therefore, in the dicing apparatus 10 of the fifth embodiment, the edge portion 110 of the workpiece W is trimmed using blades 21A and 21B. Furthermore, the dicing apparatus 10 of the fifth embodiment measures the tip shape of the blades 21A and 21B based on the stepped portions 112A and 112B (see Figure 29) formed on the edge portion 110 by the trimming process. Since the dicing apparatus 10 of the fifth embodiment has basically the same configuration as the dicing apparatus 10 of the fourth embodiment, components that are functionally or structurally identical to those of the fourth embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0159] Figure 28 is an explanatory diagram illustrating the trimming process of the edge portion 110 of the workpiece W using blades 21A and 21B. Figure 29 is a side view of the workpiece W after trimming and after back grinding.

[0160] As shown by reference numeral XXIXA in Figures 28 and 29, the machining control unit 78 of the fourth embodiment drives each spindle 22A, 22B and the relative movement mechanism 49 via the blade drive control unit 70 and the movement control unit 72 to control the execution of the trimming process of the edge portion 110.

[0161] Specifically, during trimming, the machining control unit 78 drives the relative movement mechanism 49 (rotation drive unit 38) via the movement control unit 72 to rotate the table 31 around its rotation axis CA. At the same time, the machining control unit 78 drives the relative movement mechanism 49 via the movement control unit 72 to adjust the posture and position of the blades 21A and 21B. In posture adjustment, the posture of the blades 21A and 21B is adjusted so that the blade rotation axis is parallel to the radius (diameter) of the workpiece W. In position adjustment, the relative position of the blades 21A and 21B with respect to the workpiece W is adjusted so that the cutting edges of the blades 21A and 21B contact the edge portion 110 from the front side (one side) of the workpiece W.

[0162] Next, the machining control unit 78 drives the spindles 22A and 22B via the blade drive control unit 70 to rotate the blades 21A and 21B, and simultaneously drives the relative movement mechanism 49 (Z drive unit 48) via the movement control unit 72 to move the blades 21A and 21B downward by a predetermined amount in the Z-axis direction. As a result, a trimming process is performed in which the edge portion 110 is cut away from the front surface of the workpiece W to a predetermined depth by the blades 21A and 21B, and stepped portions 112A and 112B (corresponding to the workpiece portion) are formed on the edge portion 110. The stepped portion 112A is formed by blade 21A, and the stepped portion 112B is formed by blade 21B.

[0163] By performing backside grinding on the workpiece W after trimming, the edge portion 110 is formed on a surface perpendicular to the front and back surfaces of the workpiece W, as shown by the reference numeral XXIXB in Figure 29, thereby preventing the occurrence of cracks originating from this edge portion 110.

[0164] Figure 30 is an enlarged cross-sectional view of the stepped portions 112A and 112B of the edge portion 110 of the workpiece W. As shown by the reference numeral XXXA in Figure 30, when the edges E1 and E2 of the blades 21A and 21B are in an upright position (see reference numeral XXA in Figure 20), the cross-sectional shape of the stepped portions 112A and 112B becomes a right-angle shape.

[0165] On the other hand, as shown by the reference numeral XXXB in Figure 30, when the edges E1 and E2 become rounded (R-shaped: see reference numeral XXB in Figure 20) due to wear of the blades 21A and 21B, the cross-sectional shape of the stepped portions 112A and 112B also becomes R-shaped, so the edge portion 110 is formed in a nearly acute angle. As a result, there is a risk of cracks occurring starting from this edge portion 110. Therefore, in the dicing apparatus 10 of the fifth embodiment, the tip shape of the blades 21A and 21B is measured and monitored by measuring the processing quality (cross-sectional shape) of the stepped portions 112A and 112B formed by the trimming process.

[0166] In the fifth embodiment, the measurement control unit 80 controls the white light interferometer 24 and the relative movement mechanism 49, similar to the fourth embodiment, to perform position adjustment of the white light interferometer 24, operation of the white light interferometer 24, and vertical scanning for each stepped section 112A, 112B. As a result, the processing quality measurement unit 82 of the fifth embodiment acquires an interference signal L5A from the white light interferometer 24 for each stepped section 112A, 112B.

[0167] In the fifth embodiment, the processing quality measurement unit 82 generates cross-sectional shape information 88 for each stepped section 112A, 112B based on the interference signal L5A for each stepped section 112A, 112B acquired from the white light interferometer 24, similar to the fourth embodiment. The processing quality measurement unit 82 then outputs the measurement results (cross-sectional shape information 88), which represent the processing quality of each stepped section 112A, 112B, to the blade shape measurement unit 100.

[0168] In the fifth embodiment, the blade shape measuring unit 100 measures the tip shapes of the blades 21A and 21B based on the measurement results (cross-sectional shape information 88) of the cross-sectional shape of each stepped portion 112A and 112B input from the processing quality measuring unit 82.

[0169] The trimming process of the workpiece W by the dicing device 10 in the fifth embodiment, particularly the measurement process of the cross-sectional shape (processing quality) of the stepped portions 112A and 112B and the measurement process of the tip shape of the blades 21A and 21B, are basically the same as those of the fourth embodiment shown in Figure 26. However, in the fifth embodiment, the trimming process is performed in step S2 of Figure 26, and the cross-sectional shape of the stepped portions 112A and 112B is measured in step S11.

[0170] As described above, the dicing apparatus 10 of the fifth embodiment can accurately measure the cross-sectional shape (processing quality) of the stepped portions 112A and 112B, similar to the fourth embodiment. As a result, the tip shape of the blades 21A and 21B can be accurately measured based on the cross-sectional shape of the stepped portions 112A and 112B. This allows monitoring whether the tip shape (edges E1 and E2) of the blades 21A and 21B is R-shaped during the trimming process of the edge portion 110, thereby preventing the occurrence of cracks.

[0171] [Sixth Embodiment] Figure 31 is an enlarged view of the blades 21A and 21B of the dicing apparatus 10 of the sixth embodiment. Figure 32 is an explanatory diagram for illustrating the calculation results of the cross-sectional shape along the Y-axis of the half-cut grooves 90A and 90B formed by the blades 21A and 21B of the sixth embodiment.

[0172] In each of the above embodiments, the tip shape of the blades 21A and 21B is rectangular when viewed from a direction perpendicular to the Y-axis direction (blade rotation axis). However, as shown in Figure 31, in the sixth embodiment, the tip shape of the blades 21A and 21B is V-shaped when viewed from a direction perpendicular to the Y-axis direction (blade rotation axis).

[0173] Furthermore, the dicing apparatus 10 of the sixth embodiment has basically the same configuration as the dicing apparatus 10 of the fourth embodiment, except that the tip shape of the blades 21A and 21B is formed in a V shape. Therefore, parts that are functionally or structurally identical to those of the fourth embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0174] As in the sixth embodiment, by using V-shaped blades 21A and 21B, chamfering can be performed on the workpiece W at any angle. This allows the angle of light reflection to be adjusted when the workpiece W is an optical device.

[0175] In this case, the V-shaped blades 21A and 21B also wear down with use, causing their tips to become rounded, making it impossible to cut (chamfer) the workpiece W at the design angle. Therefore, conventionally, the operator would determine the lifespan of the blades 21A and 21B by checking the cutting angle made by the blades 21A and 21B from the cross-section of the optical device (tip) after cutting.

[0176] In contrast, in the dicing apparatus 10 of the sixth embodiment, as shown in Figure 32, the tip shape of the blades 21A and 21B, more specifically the tip angle α of the blades 21A and 21B, can be accurately measured based on the measurement results of the cross-sectional shape (cross-sectional shape information 88) measured for each half-cut groove 90A and 90B, similar to the fourth embodiment. As a result, the operator can determine the lifespan of the blades 21A and 21B based on the measurement results of the tip angle α of the blades 21A and 21B without having to check the cross-section of the optical device after cutting. This determination may be performed automatically by the control unit 60.

[0177] [Seventh Embodiment] Figure 33 is a functional block diagram of the server 200 in the seventh embodiment. In each of the above embodiments, the central control unit 60 of the dicing device 10 performs the following processes: measuring the processing quality of various parts of the workpiece W, determining correction values ​​Δy1, Δy2, Δz1, Δz2 (hereinafter abbreviated as various correction values), and measuring the tip shapes of the blades 21A and 21B. In contrast, in the seventh embodiment, the server 200 performs the above processes.

[0178] As shown in Figure 33, the server 200 is connected to one or more dicing devices 10 (white light interferometer 24 and central control unit 60) via a communication interface 202. The dicing device 10 of the seventh embodiment has basically the same configuration as the dicing device 10 described in each of the above embodiments, but its central control unit 60 does not necessarily have to function as a processing quality measurement unit 82, a correction value determination unit 84, and a blade shape measurement unit 100.

[0179] The server 200 exchanges various information (data) with the dicing device 10 via its communication interface 202. The server 200 acquires interference signals L4 (interference signals L5A, L5B) from the white light interferometer 24 of the dicing device 10 via the communication interface 202. The server 200 also outputs various correction values ​​and measurement results of the tip shapes of blades 21A and 21B to the control unit 60 of the dicing device 10 via the communication interface 202.

[0180] The server 200 functions as at least an interference signal acquisition unit 204, a processing quality measurement unit 206, a correction value determination unit 208, and a blade shape measurement unit 210 by executing a control program (not shown).

[0181] The interference signal acquisition unit 204 acquires the aforementioned interference signals L5A and L5B from the white light interferometer 24 via the communication interface 202, and outputs these interference signals L5A and L5B to the processing quality measurement unit 206.

[0182] The machining quality measurement unit 206, similar to the machining quality measurement unit 82 in each of the above embodiments, measures the machining quality (machining position and machining shape) of various workpieces cut by blades 21A and 21B based on interference signals L5A and L5B acquired from the interference signal acquisition unit 204, and outputs the measurement results to the correction value determination unit 208 and the blade shape measurement unit 210.

[0183] The correction value determination unit 208, similar to the correction value determination unit 84 in the first to third embodiments described above, determines various correction values ​​based on the measurement results of the processing quality by the processing quality measurement unit 206, and outputs the various correction values ​​to the overall control unit 60 via the communication interface 202. This performs so-called feedback control, in which the processing position and shape (processing depth) of various workpieces cut by the dicing device 10 are corrected.

[0184] The blade shape measuring unit 210 measures the tip shapes of blades 21A and 21B based on the measurement results of the processing quality (cross-sectional shape) by the processing quality measuring unit 206, similar to the blade shape measuring unit 100 in the fourth to sixth embodiments described above. The measurement results of the tip shapes of blades 21A and 21B are stored in the server 200 for each dicing device 10 and are displayed on a monitor (not shown) connected to the server 200.

[0185] Furthermore, the blade shape measuring unit 210 outputs the measurement results of the tip shapes of blades 21A and 21B to the control unit 60 via the communication interface 202. As a result, the measurement results of the tip shapes of blades 21A and 21B are stored in the storage unit 64 and displayed on the display unit 66 in the dicing device 10.

[0186] As described above, in the seventh embodiment, the server 200 performs the processing of measuring the machining quality of various parts of the workpiece W, determining various correction values, and measuring the tip shapes of the blades 21A and 21B, thus achieving the same effects as in the above embodiments.

[0187] Furthermore, each process corresponding to multiple dicing devices 10 can be performed collectively by the server 200 (a high-performance computing device). As a result, the functions of the dicing devices 10 can be reduced, that is, the programs (analysis software) that execute each process can be reduced, thereby lowering the cost of the dicing devices 10.

[0188] Furthermore, the server 200 can store various data for each of the multiple dicing devices 10 (interference signals L5A, L5B, processing quality of the workpiece, various correction values, and tip shapes of blades 21A and 21B). As a result, based on the stored data, various correction values ​​can be determined (feedback control), or the tip shapes of blades 21A and 21B can be measured. Moreover, by having the server 200 perform machine learning, the measurement accuracy of the processing quality of various workpieces, the determination accuracy of various correction values, and the measurement accuracy of the tip shapes of blades 21A and 21B can be further improved.

[0189] [others] In each of the above embodiments, the dicing device 10 is provided with a pair of blades 21A, 21B and a pair of spindles 22A, 22B, but the number of blades and spindles (i.e., the number of processing heads of the present invention) may be 1 or 3 or more.

[0190] In the embodiments described above, a twin-spindle dicer (a pair of blades 21A, 21B and a pair of spindles 22A, 22B) was used as an example of the processing head of the present invention. However, the present invention can also be applied when one or more laser processing heads for performing laser processing (including ablation groove processing) on ​​the workpiece W are provided in the dicing device 10.

[0191] In each of the above embodiments, a white light interferometer 24 is provided on one of the pair of Z carriages 44 (one of the twin spindles) and a microscope 23 is provided on the other of the pair of Z carriages 44 (the other of the twin spindles). However, a white light interferometer 24 may also be provided on the other Z carriage 44 (the other of the twin spindles). Similarly, a microscope 23 may also be provided on one of the Z carriages 44. That is, a microscope 23 and a white light interferometer 24 may be provided for each of the multiple Z carriages 44. Furthermore, in each of the above embodiments, the vertical scanning described above is performed by moving the white light interferometer 24 in the Z-axis direction using the Z carriage 44, but vertical scanning may also be performed by moving the table 31 in the Z-axis direction.

[0192] In the embodiments described above, the white light interferometer 24 is mounted on the Z carriage 44, allowing the blade 21B and the white light interferometer 24 to be scanned together in the Z-axis direction. However, the white light interferometer 24 may be mounted separately from the blade 21B and the Z carriage 44. In this case, a separate actuator (carriage) capable of scanning the white light interferometer 24 in the Z-axis direction is provided.

[0193] In each of the above embodiments, the dicing apparatus 10 is provided with a Mirau-type white light interferometer 24, but any known type of white light interferometer 24, such as a Michelson-type or Fizeau-type, may be provided.

[0194] The dicing apparatus 10 of each of the above embodiments may be combined as appropriate. For example, the dicing apparatus 10 of the first embodiment and the dicing apparatus 10 of the second embodiment may be combined to simultaneously measure both the processing position and the processing shape as processing quality of various workpieces. Alternatively, the dicing apparatus 10 of the first to third embodiments and the dicing apparatus 10 of the fourth to sixth embodiments may be combined as appropriate to enable both processing quality measurement of various workpieces and measurement of the tip shape of the blades 21A and 21B.

[0195] In the embodiments described above, the measurement of the processing quality of various workpiece parts such as grooves 25A, 25B, half-cut grooves 90A, 90B, laser-processed groove 94, and stepped parts 112A, 112B was used as an example to explain the present invention. However, the present invention can also be applied to measuring the processing quality of various workpiece parts formed on the workpiece W by the dicing device 10 or other devices. [Explanation of Symbols]

[0196] 10…Dicing device, 21A,21B…Blade, 22A,22B…Spindle, 23…Microscope, 24…White light interferometer, 25A,25B…Groove, 31…Table, 49…Relative movement mechanism, 51…White light source, 56…Imaging unit, 60…General control unit, 70…Blade drive control unit, 72…Movement control unit, 74…Imaging control unit, 76…Detection control unit, 78…Processing control unit, 80…Measurement control unit, 82…Processing quality measurement unit, 84…Correction value determination unit, 86…Three-dimensional shape information, 88…Cross-sectional shape information, 90A,90B…Half-cut groove, 94…Laser processing Groove, 100...Blade shape measurement unit, 110...Edge unit, 112A, 112B...Step unit, 200...Server, 202...Communication interface, 204...Interference signal acquisition unit, 206...Processing quality measurement unit, 208...Correction value determination unit, 210...Blade shape measurement unit, C...Street, CL1, CL2...Groove center position, cy, cy1, cy2...Processing width, cz1, cz2...Processing depth, E1, E2...Edge, L1...White light, L2...Measurement light, L3...Reference light, L4, L5A, L5B...Interference signal, W...Workpiece, Δy1, Δy2, Δz1, Δz2...Correction value

Claims

[Claim 1] A table that holds the workpiece, A machining head for machining the workpiece held in the table, A relative movement mechanism for moving the machining head relative to the table, A processing quality measuring device for measuring the processing quality of a workpiece formed on a workpiece by a workpiece processing device, A white light interferometer provided integrally with the processing head, which emits white light toward a workpiece formed on the workpiece and detects an interference signal between the white light reflected by the workpiece and the white light reflected by a reference plane, A scanning control unit drives the relative movement mechanism to perform a vertical scan that moves the processing head and the white light interferometer together in a direction perpendicular to the table, thereby changing the optical path length of the white light reflected from the workpiece, A processing quality measuring unit that measures the processing quality of the workpiece based on the interference signal output from the white light interferometer during the vertical scanning, A processing quality measuring device equipped with the following features.

Images