Centering method

Abstract

A center positioning method is provided, which can easily determine the actual positional relationship between the imaging component and the detection component. The center positioning method consists of the following steps: a first center coordinate detection step (ST1), which calculates the coordinates (X1, Y1) of the center of the chuck stage based on the image captured by the imaging unit; a second center coordinate detection step (ST2), which calculates the coordinates (X2, Y2) of the center of the chuck stage based on the detection result of the detection unit; a coordinate distance calculation step (ST3), which calculates the distance α between the centers as (X1-X2) and the distance β between the centers as (Y1-Y2); and a center alignment step (ST4), which, when the imaging center of the imaging unit is positioned at the coordinates X0, Y0, the detection center of the detection unit is positioned at the coordinates X0-α, Y0-β, so that the imaging center of the imaging unit and the detection center of the detection unit are aligned.

Description

Technical Field

[0001] This invention relates to a center positioning method. Background Technology

[0002] A cutting device is used to divide a workpiece such as a semiconductor wafer into individual chips (see, for example, Patent Document 1 and Patent Document 2).

[0003] The conventional cutting apparatuses shown in Patent Documents 1 and 2 above include an imaging member for photographing the workpiece and a detection member for measuring the height of the workpiece. In these conventional cutting apparatuses, the relative positional relationship between the imaging member and the detection member is predetermined as a design value.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2015-112698

[0005] Patent Document 2: Japanese Patent Application Publication No. 2005-093710

[0006] However, the cutting device used in the past has installation errors in the installation position of at least one of the imaging component and the detection component, and the positional relationship determined by the design value is different from the actual positional relationship.

[0007] Therefore, the following problem exists: even if the cutting device used in the past detects the height of the position identified by the image captured by the imaging component and performs cutting, it is not possible to accurately perform the processing corresponding to the height detected by the imaging component.

[0008] To address this problem, Patent Document 1 proposes a method for determining the actual positional relationship between the imaging component and the detection component using a virtual chip. However, the method described in Patent Document 1 requires a virtual chip, which is rather cumbersome. Summary of the Invention

[0009] The present invention was made in view of the above-mentioned problems, and its object is to provide a center positioning method that can easily grasp the actual positional relationship between the imaging component and the detection component.

[0010] To address the aforementioned issues and achieve the objective, the center positioning method of the present invention positions the detection center of a detection member at the imaging center of an imaging member within an apparatus. This apparatus includes: a circular chuck stage for holding a workpiece; an X-axis moving member for moving the chuck stage in the X-axis direction; the imaging member for imaging the workpiece held by the chuck stage; a first Y-axis moving member for moving the imaging member in the Y-axis direction; a detection member for detecting the height of the workpiece held by the chuck stage; and a second Y-axis moving member for moving the detection member in the Y-axis direction. The center positioning method is characterized by comprising the following steps: a first center coordinate detection step, in which the X-axis moving member and the first Y-axis moving member are activated and the coordinates (X1, Y1) of the center of the chuck stage are determined based on the image captured by the imaging member; a second center coordinate detection step, in which the X-axis moving member and the second Y-axis moving member are activated and the first Y-axis moving member are activated and the first Y-axis moving member is moved in the Y-axis direction; and a second center coordinate detection step, in which the X-axis moving member and the first Y-axis moving member are activated and the first Y-axis moving member are moved in the Y-axis direction; and a second Y-axis moving member is activated and the second Y-axis moving member is moved in the Y-axis direction. The Y-axis moving component moves and calculates the coordinates (X2, Y2) of the center of the chuck stage based on the detection result of the detection component; the coordinate distance calculation step sets the X coordinate of the center of the chuck stage, calculated based on the image captured by the imaging component, as X1, and the X coordinate of the center of the chuck stage, calculated based on the detection result of the detection component, as X2, and calculates the distance α between the centers as (X1-X2); the Y coordinate of the center of the chuck stage, calculated based on the image captured by the imaging component, as Y1, and the Y coordinate of the center of the chuck stage, calculated based on the detection result of the detection component, as Y2, and calculates the distance β between the centers as (Y1-Y2); and the center alignment step, when the imaging center of the imaging component is positioned at the coordinates X0, Y0, the detection center of the detection component is positioned at the coordinates X0-α, Y0-β to make the imaging center of the imaging component and the detection center of the detection component consistent.

[0011] In the center positioning method, the first center coordinate detection step can be as follows: the imaging component compares the feature point on the outer periphery of the center of the chuck table with the feature point and takes a picture to obtain the coordinates (X11, Y11). The chuck table is rotated at any angle to take a picture of the feature point and obtain the coordinates (X12, Y12). The coordinates of the center of the chuck table are obtained by taking the coordinates of the point at a position that is half the distance between the two coordinates on a linear function that passes through the center of the center of the obtained coordinates (X11, Y11) and the center of the feature point (X12, Y12). The second center coordinate detection step detects the coordinates of three or more points of the detection component on the outer periphery of the chuck table where the detection result changes drastically. The coordinates (X2, Y2) of the center of the chuck table are obtained based on the coordinates of the three or more detected points.

[0012] In the center positioning method, the first center coordinate detection step may involve taking a picture of the area including the outer periphery of the chuck table, detecting the coordinates of three or more points of the center of the imaging component located on the outer periphery based on the captured image, and calculating the coordinates (X1, Y1) of the center of the chuck table based on the detected coordinates of the three or more points. The second center coordinate detection step may involve detecting the coordinates of three or more points of the detection component located on the outer periphery of the chuck table where the detection result changes drastically, and calculating the coordinates (X2, Y2) of the center of the chuck table based on the detected coordinates of the three or more points.

[0013] In the center positioning method, the imaging component may be disposed on a first processing component connected to the first Y-axis moving component, and the detection component may be disposed on a second processing component connected to the second Y-axis moving component.

[0014] In the center positioning method, the first Y-axis moving member and the second Y-axis moving member may be a single Y-axis moving member, and the imaging member and the detection member may be disposed on a processing member connected to the Y-axis moving member.

[0015] The present invention enables easy determination of the actual positional relationship between the imaging component and the detection component. Attached Figure Description

[0016] Figure 1 This is a perspective view showing a structural example of a processing apparatus for implementing the center positioning method of Embodiment 1.

[0017] Figure 2 It is shown schematically. Figure 1 A top view of the shooting center of the shooting unit of the processing device shown.

[0018] Figure 3 It is shown schematically. Figure 1 A top view of the detection center of the detection unit of the processing device shown.

[0019] Figure 4 It is shown Figure 1 A top view of the coordinate system of the shooting position of the shooting unit and the detection position of the detection unit of the processing device shown.

[0020] Figure 5 This is a flowchart illustrating the process of the center positioning method in Embodiment 1.

[0021] Figure 6 It is shown in Figure 5 The image shown is a top view of the state in which the imaging unit captures the feature points of the holding surface of the chuck table during the first center coordinate detection process.

[0022] Figure 7 It is shown in Figure 5 In the first center coordinate detection process shown, the imaging unit detects the coordinates from... Figure 6 The image shows a top view of the chuck table's retaining surface, which has been rotated at a specified angle, and the image is taken from a point on the surface.

[0023] Figure 8 It is shown schematically in Figure 5 The side view of the second center coordinate detection process of the positioning method shown, in which the detection unit moves along the holding surface of the chuck table.

[0024] Figure 9 It is shown Figure 8 The graph shows the detection results of the detection unit.

[0025] Figure 10 It shows the basis Figure 9 The top view shows three points on the outer periphery of the chuck table, determined by the detection results of the detection unit.

[0026] Figure 11 This is a top view schematically showing the state in which the imaging unit captures images of three points on the outer periphery of the chuck worktable during the first center coordinate detection step of the center positioning method in Embodiment 2.

[0027] Figure 12 This is a perspective view showing an example of the structure of a processing apparatus that implements the center positioning method of Embodiment 1 and Embodiment 2.

[0028] Label Explanation

[0029] 1. 1-1: Machining device; 10: Chuck table; 12: Center; 13: Feature point; 21: First cutting unit (first machining component); 21-1: Cutting unit (machining component); 22: Second cutting unit (second machining component); 30: Imaging unit (imaging component); 31: Image; 32: Imaging center; 40: Detection unit (detection component); 42: Detection center; 51: X-axis moving unit (X-axis moving component); 52: First Y-axis moving unit (first Y-axis moving component); 52-1: Y-axis moving unit (Y-axis moving component); 53: Second Y-axis moving unit (second Y-axis moving component); 200: Workpiece; ST1: First center coordinate detection process; ST2: Second center coordinate detection process; ST3: Coordinate distance calculation process; ST4: Center alignment process. Detailed Implementation

[0030] The embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the constituent elements described below include substantially the same constituent elements readily conceived by those skilled in the art. Moreover, the structures described below can be appropriately combined. Furthermore, various omissions, substitutions, or modifications to the structure can be made without departing from the spirit of the present invention.

[0031] [Implementation Method 1]

[0032] The center positioning method of Embodiment 1 of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a perspective view showing a structural example of a processing apparatus for implementing the center positioning method of Embodiment 1. Figure 2 It is shown schematically. Figure 1 A top view of the shooting center of the shooting unit of the processing device shown. Figure 3 It is shown schematically. Figure 1 A top view of the detection center of the detection unit of the processing device shown. Figure 4 It is shown Figure 1 A top view of the coordinate system of the shooting position of the shooting unit and the detection position of the detection unit of the processing device shown. Figure 5 This is a flowchart illustrating the process of the center positioning method in Embodiment 1.

[0033] (Processing equipment)

[0034] The center positioning method of Implementation 1 uses a device Figure 1 The processing is carried out using the processing apparatus 1 shown. Processing apparatus 1 is for... Figure 1 The cutting apparatus shown is used to cut the workpiece 200. In Embodiment 1, the workpiece 200 is a wafer such as a disc-shaped semiconductor wafer or optical device wafer made of silicon, sapphire, gallium, etc. The workpiece 200 has devices 203 formed in a grid-like region divided by multiple predetermined dividing lines 202 formed in a grid pattern on the front side 201.

[0035] Alternatively, the workpiece 200 of the present invention can also be a so-called TAIKO (registered trademark) wafer with a thinned central portion and a thick-walled portion formed on the outer periphery. Besides wafers, it can also be a rectangular packaging substrate having multiple resin-sealed devices, a ceramic substrate, a ferrite substrate, or a substrate containing at least one of nickel and iron. In Embodiment 1, the back surface 204 of the workpiece 200 is adhered to an adhesive tape 206 with an annular frame 205 mounted on its outer periphery and supported by the annular frame 205.

[0036] Figure 1The machining apparatus 1 shown is a cutting apparatus that uses a chuck table 10 to hold the workpiece 200 and uses a cutting tool 23 to perform cutting (equivalent to machining) along a predetermined dividing line 202. Figure 1 As shown, the processing apparatus 1 includes: a chuck table 10 with a circular planar shape, which holds a workpiece 200 by means of a holding surface 11; a first cutting unit 21 as a first processing member, which cuts the workpiece 200 held by the chuck table 10 by means of a cutting tool 23; a second cutting unit 22 as a second processing member, which cuts the workpiece 200 held by the chuck table 10 by means of a cutting tool 23; an imaging unit 30 as an imaging member, which takes a picture of the workpiece 200 held by the chuck table 10; an detection unit 40 as a detection member, which measures the height of the workpiece 200 held by the chuck table 10; and a control unit 100.

[0037] And, as Figure 1 As shown, the machining apparatus 1 includes a moving unit 50 that moves the chuck table 10 and the cutting unit 20 relative to each other. The moving unit 50 includes: an X-axis moving unit 51 that feeds the chuck table 10 along the X-axis direction parallel to the horizontal direction; a first Y-axis moving unit 52 that indexes the first cutting unit 21 and the imaging unit 30 along the Y-axis direction parallel to the horizontal direction and perpendicular to the X-axis direction; a second Y-axis moving unit 53 that indexes the first cutting unit 21 and the detection unit 40 along the Y-axis direction; a first Z-axis moving unit 54 that feeds the first cutting unit 21 along the Z-axis direction parallel to both the X-axis and Y-axis directions; a second Z-axis moving unit 55 that feeds the second cutting unit 22 along the Z-axis direction; and a rotational moving unit 56 that rotates the chuck table 10 about an axis parallel to the Z-axis direction. Figure 1 As shown, the processing device 1 is a device having a first cutting unit 21 and a second cutting unit 22, that is, a cutting machine with two spindles, a so-called facing dual type cutting device.

[0038] The X-axis moving unit 51 is an X-axis moving member that moves the chuck table 10 in the X-axis direction, which is the machining feed direction, to perform relative machining feed along the X-axis direction. The first Y-axis moving unit 52 is a first Y-axis moving member that moves the first cutting unit 21 and the imaging unit 30 in the indexing feed direction, i.e., the Y-axis direction, to perform relative indexing feed along the Y-axis direction. The second Y-axis moving unit 53 is a second Y-axis moving member that moves the second cutting unit 22 and the detection unit 40 in the indexing feed direction, i.e., the Y-axis direction, to perform relative indexing feed along the Y-axis direction.

[0039] The first Z-axis moving unit 54 is a first Z-axis moving member that moves the first cutting unit 21 and the imaging unit 30 in the cutting feed direction (i.e., the Z-axis direction) to perform relative cutting feed along the Z-axis direction. The second Z-axis moving unit 55 is a second Z-axis moving member that moves the second cutting unit 22 and the detection unit 40 in the cutting feed direction (i.e., the Z-axis direction) to perform relative cutting feed along the Z-axis direction.

[0040] The X-axis moving unit 51, Y-axis moving units 52, 53 and Z-axis moving units 54, 55 have a known ball screw that is rotatable about an axis, a known electric motor that rotates the ball screw about an axis, and a known guide rail that supports the chuck table 10 or the cutting unit 20 so that it can move freely in the X-axis direction, Y-axis direction or Z-axis direction.

[0041] The chuck table 10 is disc-shaped, and the holding surface 11 for holding the workpiece 200 is formed of porous ceramic or the like. Furthermore, the chuck table 10 is configured to move freely along the X-axis in the entire range of the machining area below the cutting unit 20 and the loading / unloading area where the workpiece 200 is moved in and out from below the cutting unit 20 via the X-axis moving unit 51, and is also configured to rotate freely about an axis parallel to the Z-axis via the rotary moving unit 56. The chuck table 10 is connected to a vacuum suction source (not shown), and is attracted and held by the vacuum suction source to hold the workpiece 200 placed on the holding surface 11. In Embodiment 1, the chuck table 10 attracts and holds the back side 204 of the workpiece 200 via the adhesive tape 206.

[0042] The first cutting unit 21 and the second cutting unit 22 are cutting components in which the cutting tool 23, which cuts the workpiece 200 held on the chuck table 10, is mounted and detachable. The first cutting unit 21 is connected to the first Y-axis moving unit 52 and is configured to move freely in the Y-axis direction via the first Y-axis moving unit 52 relative to the workpiece 200 held on the chuck table 10, and is configured to move freely in the Z-axis direction via the first Z-axis moving unit 54. The first cutting unit 21 is mounted on a column of a portal-shaped support frame 3 erected from the main body 2 via the first Y-axis moving unit 52, the first Z-axis moving unit 54, etc.

[0043] The second cutting unit 22 is connected to the second Y-axis moving unit 53 and is configured to move freely in the Y-axis direction via the second Y-axis moving unit 53 and in the Z-axis direction via the second Z-axis moving unit 55 relative to the workpiece 200 held on the chuck table 10. The second cutting unit 22 is mounted on another column of the support frame 3 via the second Y-axis moving unit 53, the second Z-axis moving unit 55, etc. In addition, the upper ends of the columns of the support frame 3 are connected to each other by a horizontal beam. The first cutting unit 21 and the second cutting unit 22 can position the cutting tool 23 at any position on the holding surface 11 of the chuck table 10 via the Y-axis moving units 52, 53 and the Z-axis moving units 54, 55.

[0044] Each cutting unit 21, 22 has: an extremely thin cutting tool 23 as a cutting abrasive, having a generally annular shape; a spindle housing 24, which is configured to move freely in the Y-axis direction and the Z-axis direction via Y-axis moving units 52, 53 and Z-axis moving units 54, 55; and a spindle, which is rotatably disposed in the spindle housing 24 about an axis and serves as a rotating axis on which the cutting tool 23 is mounted.

[0045] The imaging unit 30 is disposed in the first cutting unit 21. In Embodiment 1, the imaging unit 30 is fixed to the first cutting unit 21 in a manner that allows it to move integrally with the first cutting unit 21. The imaging unit 30 has multiple imaging elements that capture images of the area to be divided of the workpiece 200 held on the chuck table 10 before cutting. The imaging elements are, for example, CCD (Charge-Coupled Device) imaging elements or CMOS (Complementary MOS) imaging elements. The imaging unit 30 captures images of the workpiece 200 held on the chuck table 10 to obtain images used for alignment, etc., of the workpiece 200 and the cutting tool 23. Figure 2 Image 31 is shown as an example. The obtained image 31 is output to the control unit 100.

[0046] Additionally, in implementation method 1, such as Figure 2 As shown, the image 31 captured by the imaging unit 30 is a rectangle whose longer side is parallel to the Y-axis and whose shorter side is parallel to the X-axis. Furthermore, the imaging center 32 of the imaging unit 30 refers to the center of image 31 along both the X-axis and Y-axis. The position of the imaging unit 30 relative to the imaging center 32, i.e., the center of image 31, along the Z-axis is also relative to the position of the imaging unit 30.

[0047] The detection unit 40 is disposed in the second cutting unit 22. In Embodiment 1, the imaging unit 30 is fixed to the second cutting unit 22 in a manner that allows it to move integrally with the second cutting unit 22. In Embodiment 1, the detection unit 40 is a back pressure sensor that detects the height, i.e., the position in the Z-axis direction, of the workpiece 200 held on the chuck table 10. However, in this invention, it is not limited to a back pressure sensor; it can also be a laser displacement gauge or a contact sensor. The detection unit 40 detects... Figure 3 The height of the detection center 42 within the detection range 41 shown is the position in the Z-axis direction, and the detection result is output to the control unit 100.

[0048] Additionally, in implementation method 1, such as Figure 3 As shown, the detection range 41 of the detection unit 40 is circular. Furthermore, the detection center 42 of the detection unit 40 refers to the center of the detection range 41 along both the X-axis and Y-axis directions. The detection unit 40 is positioned relative to the detection center 42 along the Z-axis direction.

[0049] Furthermore, the processing device 1 includes: an X-axis position detection unit 61 for detecting the X-axis position of the chuck table 10; a first Y-axis position detection unit 62 for detecting the Y-axis positions of the first cutting unit 21 and the imaging unit 30; a second Y-axis position detection unit 63 for detecting the Y-axis positions of the second cutting unit 22 and the imaging unit 40; a first Z-axis position detection unit 64 for detecting the Z-axis positions of the first cutting unit 21 and the imaging unit 30; and a second Z-axis position detection unit 65 for detecting the Z-axis positions of the second cutting unit 22 and the imaging unit 40.

[0050] The X-axis position detection unit 61 and Y-axis position detection units 62 and 63 can be composed of a linear scale and a reading head parallel to the X-axis or Y-axis direction. The Z-axis position detection units 64 and 65 detect the Z-axis position of the cutting units 21 and 22 by pulses from the motors of the Z-axis movement units 54 and 55. The X-axis position detection units 61, Y-axis position detection units 62 and 63, and Z-axis position detection units 64 and 65 output the X-axis position of the chuck table 10, the Y-axis position of the cutting unit 20, the imaging unit 30, and the detection unit 40 to the control unit 100.

[0051] Furthermore, in Embodiment 1, the position in the Z-axis direction is determined based on the height from the holding surface 11 of the chuck table 10, using the holding surface 11 as a reference position. Also, in Embodiment 1, the coordinate system 301 (hereinafter referred to as the first coordinate system) determined by the X-axis and Y-axis directions of the first cutting unit 21 and the imaging unit 30, and the coordinate system 302 (hereinafter referred to as the second coordinate system) determined by the X-axis and Y-axis directions of the second cutting unit 22 and the detection unit 40 are as follows: Figure 4 As shown, the X-axis directions are the same, while the Y-axis directions are different.

[0052] In embodiment 1, the X-axis and Y-axis positions of the first cutting unit 21 and the imaging unit 30 are determined from a reference position 301-1 predetermined in the first coordinate system 301 (in... Figure 4 As shown in the example, the distance from the reference position (hereinafter referred to as the first reference position) parallel to the horizontal directions of the X-axis and Y-axis is determined. Furthermore, the positions of the second cutting unit 22 and the detection unit 40 in the X-axis and Y-axis directions are determined from the reference position 302-1 (predetermined in the second coordinate system 302) in the second coordinate system 302. Figure 4 As shown in the example, the distance from the horizontal direction parallel to the X-axis and Y-axis directions (hereinafter referred to as the second reference position) is used to determine the position.

[0053] The control unit 100 controls each structural element of the processing apparatus 1 to enable the processing apparatus 1 to perform processing actions on the workpiece 200. Furthermore, the control unit 100 is a computer, which includes: an arithmetic processing unit, having a microprocessor such as a CPU (central processing unit); a storage device, having a memory such as ROM (read-only memory) or RAM (random access memory); and an input / output interface device. The arithmetic processing unit of the control unit 100 performs arithmetic processing according to the computer program stored in the storage device, and outputs control signals for controlling the processing apparatus 1 to each structural element of the processing apparatus 1 via the input / output interface device.

[0054] The control unit 100 is connected to a display unit (not shown) consisting of a liquid crystal display device or the like that displaying the status of the processing action, images, etc., and an input unit (not shown) used by the operator to register processing information. The input unit consists of at least one of an external input device such as a touch panel or a keyboard provided on the display unit.

[0055] In addition, such as Figure 1 As shown, the control unit 100 includes a center coordinate detection unit 101, a coordinate system matching unit 102, and a machining control unit 103. The center coordinate detection unit 101 and the coordinate system matching unit 102 determine the relative relationship between the first coordinate system 301 and the second coordinate system 302.

[0056] The center coordinate detection unit 101 uses the image 31 captured by the imaging unit 30 in the first coordinate system 301 to determine the center 12 of the chuck table 10. Figure 4 The coordinates (X1, Y1) of the chuck table 10 are shown. The center coordinate detection unit 101 uses the detection result of the detection unit 40 in the second coordinate system 302 to determine the coordinates (X2, Y2) of the center 12 of the chuck table 10, which is located in the first coordinate system 301 at the position where the coordinates (X1, Y1) of the center 12 have been determined.

[0057] The coordinate system matching unit 102 determines the relationship between the first coordinate system 301 and the second coordinate system 302 based on the coordinates (X1, Y1) of the center 12 of the chuck table 10 obtained in the first coordinate system 301 and the coordinates (X2, Y2) of the center 12 of the chuck table 10 obtained in the second coordinate system 302.

[0058] The machining control unit 103 stores the relative positions of the imaging center 32 and the lower ends of the cutting edges of the cutting tools 23 of the first cutting unit 21, and the relative positions of the detection center 42 and the lower ends of the cutting edges of the cutting tools 23 of the second cutting unit 22. Using the relationship between the first coordinate system 301 and the second coordinate system 302 obtained by the coordinate system matching unit 102, and the pre-stored relative positions, the machining control unit 103 controls each component in a manner that ensures the imaging center 32 and the detection center 42 are aligned, or in a manner that ensures the position captured by the imaging unit 30 is aligned with the position detected by the detection unit 40, thereby controlling the machining operation of the machining device 1.

[0059] Furthermore, the functions of the center coordinate detection unit 101, the coordinate system matching unit 102, and the machining control unit 103 are realized by the arithmetic processing device executing the computer program stored in the storage device.

[0060] (Center-based localization method)

[0061] The center positioning method is implemented when at least one of the chuck table 10, the imaging unit 30, and the detection unit 40 is newly installed, or when at least one of the chuck table 10, the imaging unit 30, and the detection unit 40 is replaced due to wear and tear or malfunction. The center positioning method is a method of positioning the detection center 42 of the detection unit 40 to the imaging center 32 of the imaging unit 30, that is, a method of determining the relationship between the first coordinate system 301 and the second coordinate system 302, and a method of making the position captured by the imaging unit 30 consistent with the position detected by the detection unit 40. When the control unit 100 receives a start instruction from the operator regarding the center positioning method, the processing device 1 begins the center positioning method. Figure 5 As shown, the center positioning method consists of a first center coordinate detection process ST1, a second center coordinate detection process ST2, a coordinate distance calculation process ST3, and a center alignment process ST4.

[0062] (First center coordinate detection process)

[0063] Figure 6 It is shown in Figure 5 The image shown is a top view of the state in which the imaging unit captures the feature points of the holding surface of the chuck table during the first center coordinate detection process. Figure 7 It is shown in Figure 5 In the first center coordinate detection process shown, the imaging unit detects the coordinates from... Figure 6 The image shows a top view of the chuck table's retaining surface, which has been rotated to a specified angle, and the image is taken from a point on the surface.

[0064] The first center coordinate detection step ST1 is a process in which the X-axis movement unit 51 and the first Y-axis movement unit 52 are activated to determine the coordinates (X1, Y1) of the center 12 of the chuck table 10 in the first coordinate system 301 based on the image 31 captured by the imaging unit 30. In the first center coordinate detection step ST1, the operator operates the input unit to activate the X-axis movement unit 51 and the first Y-axis movement unit 52, so that the feature point 13, which can be identified with other parts of the holding surface 11 and is located on the outer periphery of the center 12, is opposite to the imaging unit 30 in the Z-axis direction.

[0065] In the first center coordinate detection process ST1, the operator operates the input unit, such as... Figure 6 As shown, feature point 13 is captured by the imaging unit 30. Then, in the first center coordinate detection process ST1, the center coordinate detection unit 101 of the control unit 100 calculates the coordinates (X11, Y11) of feature point 13 in the first coordinate system 301 based on the detection results of the X-axis position detection unit 61 and the first Y-axis position detection unit 62.

[0066] In the first center coordinate detection process ST1, the operator manipulates the input unit to cause the rotation and movement unit 56 to move, such as... Figure 7 As shown, the chuck table 10 can be rotated around its axis by any predetermined angle θ. Furthermore, in Embodiment 1, the predetermined angle θ is 90 degrees, but this is not limited to 90 degrees in this invention.

[0067] In the first center coordinate detection step ST1, the operator operates the input unit to move the X-axis movement unit 51 and the first Y-axis movement unit 52, so that the feature point 13 of the holding surface 11 is opposite to the imaging unit 30 in the Z-axis direction. In the first center coordinate detection step ST1, the operator operates the input unit to capture the feature point 13 through the imaging unit 30. Then, in the first center coordinate detection step ST1, the center coordinate detection unit 101 of the control unit 100 calculates the coordinates (X12, Y12) of the feature point 13 in the first coordinate system 301 based on the detection results of the X-axis position detection unit 61 and the first Y-axis position detection unit 62.

[0068] In the first center coordinate detection process ST1, the center coordinate detection unit 101 of the control unit 100 uses the following formula 1 to calculate the distance d between the two coordinates (X11, Y11) and coordinates (X12, Y12) of the feature point 13.

[0069]

[0070] In the first center coordinate detection process ST1, the center coordinate detection unit 101 of the control unit 100 uses the following formula 2 to calculate the distance r between the position specified by the coordinates (X11, Y11) and the center 12 of the chuck table 10.

[0071]

[0072] In the first center coordinate detection process ST1, the center coordinate detection unit 101 of the control unit 100 uses the following formulas 3 and 4 to calculate the coordinates (X1, Y1) of the center 12 of the chuck table 10 in the first coordinate system 301.

[0073]

[0074]

[0075] Thus, in the first center coordinate detection step ST1 of the center positioning method of Embodiment 1, the coordinates of the position of the line 15 through the center 12 and each coordinate (X11, Y11) and coordinate (X12, Y12) at an angle θ are obtained as the coordinates (X1, Y1) of the center 12 of the chuck table 10. The line 15 passes through the center 16 of the coordinates (X11, Y11) of the obtained feature point 13 and the coordinates (X12, Y12) of the feature point 13 and is perpendicular to the line 14 connecting the coordinates (X11, Y11) and the coordinates (X12, Y12). Thus, the first center coordinate detection step ST1 of the center positioning method of Embodiment 1 will determine the coordinates (X1, Y1) of the center 12 of the chuck table 10 as half the distance d between the center and the coordinates (X11, Y11) and (X12, Y12) of the feature point 13, which are perpendicular to the center 12 of the feature point 13.

[0076] (Second center coordinate detection process)

[0077] Figure 8 It is shown schematically in Figure 5 The side view of the second center coordinate detection process of the positioning method shown, in which the detection unit moves along the holding surface of the chuck table. Figure 9 It is shown Figure 8 The graph shows the detection results of the detection unit. Figure 10 It shows the basis Figure 9 The top view shows three points on the outer periphery of the chuck table, determined by the detection results of the detection unit.

[0078] The second center coordinate detection process ST2 is a process in which the X-axis moving unit 51 and the second Y-axis moving unit 53 are activated, and the coordinates (X2, Y2) of the center 12 of the chuck table 10 in the second coordinate system 302 are determined based on the detection results of the detection unit 40. In the second center coordinate detection process ST2, the operator operates the input unit to activate the X-axis moving unit 51 and the second Y-axis moving unit 53, such as... Figure 8 As shown, while moving the detection unit 40 along the holding surface 11, the position of the holding surface 11 in the Z-axis direction is detected by the detection unit 40.

[0079] Therefore, in the detection results of detection unit 40, such as Figure 9 As shown, position 19 exhibits a sharp change in the Z-axis direction. Additionally, Figure 9 The horizontal axis represents the distance from the specified position in a direction parallel to the holding surface 11. Figure 9The vertical axis represents the position in the Z-axis direction detected by the detection unit 40. Additionally, Figure 9 The vertical axis represents the direction as Figure 9 It is located on the upper side of the chuck table 10. In addition, when the detection result changes drastically, the position 19 of the detection unit 40 is positioned at a position closer to the outer periphery than the outer edge of the chuck table 10.

[0080] In the second center coordinate detection step ST2, the center coordinate detection unit 101 of the control unit 100 determines the positions 19-1, 19-2, and 19-3 of the detection unit 40 when the detection result changes drastically, based on the detection result of the detection unit 40. In Embodiment 1, in the second center coordinate detection step ST2, as... Figure 10 As shown, the center coordinate detection unit 101 of the control unit 100 determines the three points 19-1, 19-2, and 19-3 of the detection unit 40 when the detection result changes drastically. However, in this invention, the determined points 19-1, 19-2, and 19-3 are not limited to three points.

[0081] In the second center coordinate detection process ST2, the center coordinate detection unit 101 of the control unit 100 calculates the coordinates (X21, Y21) of the position 19-1, the coordinates (X22, Y22) of the position 19-2, and the coordinates (X22, Y22) of the position 19-3 of the determined three points in the second coordinate system 302 based on the detection results of the X-axis position detection unit 61 and the second Y-axis position detection unit 63.

[0082] Here, when the coordinates of the center 12 of the chuck table 10 in the second coordinate system 302 are set to (X2, Y2), and the radius of the circle passing through the three points 19-1, 19-2, and 19-3 is set to R, the following equation 5 holds.

[0083] (X-X2) 2 +(Y-Y2) 2 =R 2 …(Equation 5)

[0084] In the second center coordinate detection process ST2, the center coordinate detection unit 101 of the control unit 100 substitutes each coordinate (X21, Y21), (X22, Y22) and (X22, Y22) into X and Y in Equation 5 to calculate the coordinates (X2, Y2) of the center 12 of the chuck table 10 in the second coordinate system 302.

[0085] Thus, in the second center coordinate detection step ST2 of the center positioning method of Embodiment 1, the coordinates (X21, Y21), (X22, Y22), and (X22, Y22) of three or more points 19-1, 19-2, and 19-3 of the detection unit 40 located on the outer periphery of the chuck table 10 where the detection result changes drastically are detected. Based on the detected coordinates (X21, Y21), (X22, Y22), and (X22, Y22) of the three or more points 19-1, 19-2, and 19-3, the coordinates (X2, Y2) of the center 12 of the chuck table 10 in the second coordinate system 302 are calculated.

[0086] (Calculation process for distance between coordinates)

[0087] The coordinate distance calculation step ST3 is as follows: The X-coordinate of the center 12 of the chuck stage 10 in the first coordinate system 301, obtained based on the image 31 captured by the imaging unit 30, is set as X1. The X-coordinate of the center 12 of the chuck stage 10 in the second coordinate system 302, obtained based on the detection result of the detection unit 40, is set as X2. The distance α between the centers 12 is calculated as (X1-X2). The Y-coordinate of the center 12 of the chuck stage 10 in the first coordinate system 301, obtained based on the image 31 captured by the imaging unit 30, is set as Y1. The Y-coordinate of the center of the chuck stage 10 in the second coordinate system 302, obtained based on the detection result of the detection unit 40, is set as Y2. The distance β between the centers 12 is calculated as (Y1-Y2). In the coordinate distance calculation step ST3, the coordinate system matching unit 102 of the control unit 100 calculates X1-X2 to calculate the distance α, and calculates Y1-Y2 to calculate the distance β.

[0088] (Center Consistency Process)

[0089] The center alignment process ST4 is a process in which the shooting center 32 of the shooting unit 30 is positioned at the coordinates X0, Y0, and the detection center 42 of the detection unit 40 is positioned at the coordinates X0-α, Y0-β, so that the shooting center 32 of the shooting unit 30 and the detection center 42 of the detection unit 40 are aligned. In the center alignment process ST4, when the coordinates of the shooting center 32 of the shooting unit 30 in the first coordinate system 301 are set to (X0, Y0), and the coordinates of the detection center 42 of the detection unit 40 in the second coordinate system are set to (X02, Y02), the coordinate system matching unit 102 of the control unit 100 uses the following equations 6 and 7 to transform the coordinate system of the detection center 42 of the detection unit 40 from the second coordinate system 302 to the first coordinate system 301.

[0090] X02=X0-α…(Equation 6)

[0091] Y02=Y0-β…(Formula 7)

[0092] Thus, in the center alignment process ST4, when the coordinate system matching unit 102 of the control unit 100 transforms the coordinate system of the detection center 42 of the detection unit 40 from the second coordinate system 302 to the first coordinate system 301 and positions the shooting center 32 of the shooting unit 30 at the position as coordinate (X0, Y0), the detection center 42 of the detection unit 40 is positioned at the position as coordinate (X0-α, Y0-β), thereby making the shooting center 32 of the shooting unit 30 in the first coordinate system 301 consistent with the detection center 42 of the detection unit 40 in the second coordinate system 302. Furthermore, in the center alignment process ST4, the coordinate system matching unit 102 of the control unit 100 uses Equations 6 and 7 to set either coordinate (X0, Y0) or coordinate (X02, Y02) as arbitrary coordinates, thereby determining the relationship between arbitrary coordinates (X0, Y0) of the first coordinate system 301 and arbitrary coordinates (X02, Y02) of the second coordinate system 302 as shown in Equations 6 and 7, and ending the positioning method.

[0093] (Processing actions of the processing device)

[0094] In the machining apparatus 1, the operator registers the machining content information in the control unit 100 and places the workpiece 200, before cutting, on the holding surface 11 of the chuck table 10. Then, the machining apparatus 1 begins the machining operation upon receiving a start instruction from the operator. When the machining operation begins, the machining apparatus 1 holds the back side 204 side on the holding surface 11 of the chuck table 10 through the adhesive tape 206.

[0095] During the machining process, the X-axis movement unit 51 of the machining apparatus 1 moves the chuck table 10 toward the machining area, and the imaging unit 30 captures an image of the workpiece 200. Alignment is then performed based on the image 31 captured by the imaging unit 30. Additionally, the detection unit 40 detects the position of the workpiece 200 in the Z-axis direction.

[0096] While moving the workpiece 200 and the cutting unit 20 relative to each other along the predetermined dividing lines 202, the processing device 1 cuts the workpiece 200 into individual components 203 by inserting the cutting tool 23 into each predetermined dividing line 202. When the processing device 1 performs cutting on the workpiece 200 along the predetermined dividing lines 202, the processing control unit 103 of the control unit 100 uses Equations 6 and 7 to control each component in a manner that matches the position captured by the imaging unit 30 with the position detected by the detection unit 40, thereby controlling the processing operation of the processing device 1. The processing device 1 cuts along all the predetermined dividing lines 202, and the processing operation ends when the workpiece 200 is divided into individual components 203.

[0097] As explained above, the center positioning method of Embodiment 1, based on the image 31 captured by the imaging unit 30, the detection results of the detection unit 40, and the detection results of each position detection unit 61, 62, and 63, can determine the relationship between the coordinates (X0, Y0) of the imaging center 32 of the imaging unit 30 and the coordinates (X02, Y02) of the detection center 42 of the detection unit 40 in the first coordinate system 301. This allows the positional relationship between the imaging unit 30 and the detection unit 40 to be determined even when nothing is loaded on the chuck table 10. As a result, the center positioning method of Embodiment 1 effectively allows for easy determination of the actual positional relationship between the imaging unit 30 and the detection unit 40.

[0098] [Implementation Method 2]

[0099] The center positioning method of Embodiment 2 of the present invention will be described with reference to the accompanying drawings. Figure 11 This is a top view schematically showing the state in which the imaging unit captures images of three points on the outer periphery of the chuck worktable during the first center coordinate detection step of the center positioning method in Embodiment 2. Additionally, in Figure 11 In this document, parts identical to those in Embodiment 1 are labeled with the same reference numerals and their descriptions are omitted. The center positioning method in Embodiment 2 is identical to that in Embodiment 1, except for the first center coordinate detection step ST1.

[0100] In the first center coordinate detection step ST1 of Embodiment 2, the operator operates the input unit to move the X-axis movement unit 51 and the first Y-axis movement unit 52, thereby positioning the outer periphery of the chuck table 10 opposite the imaging unit 30 in the Z-axis direction. In the first center coordinate detection step ST1 of Embodiment 2, the operator operates the input unit to intermittently rotate the chuck table 10 by a predetermined angle using the rotation movement unit 56. During the periods when the chuck table 10 is stationary, the imaging unit 30 takes three or more images of the area 33, including the outer periphery of the chuck table 10. In Embodiment 2, the imaging unit 30 takes three images of the area 33, but this invention is not limited to three images.

[0101] In the first center coordinate detection process ST1 of Embodiment 2, the center coordinate detection unit 101 of the control unit 100 calculates the coordinates (X13, Y13) of the position 32-1, the coordinates (X14, Y14) of the position 32-2, and the coordinates (X15, Y15) of the position 32 of the shooting center 32 when the shooting unit 30 shoots each region 33, based on the detection results of the X-axis position detection unit 61 and the first Y-axis position detection unit 62.

[0102] In the first center coordinate detection process ST1 of Embodiment 2, the center coordinate detection unit 101 of the control unit 100 substitutes each coordinate (X13, Y13), (X14, Y14) and (X15, Y15) into X and Y in Equation 5 to calculate the coordinates (X1, Y1) of the center 12 of the chuck table 10 in the first coordinate system 301.

[0103] Thus, the first center coordinate detection step ST1 of the center positioning method of Embodiment 2 takes pictures of the area including the outer periphery of the chuck worktable 10. Based on the captured image 31, the coordinates (X13, Y13), (X14, Y14), and (X15, Y15) of three or more points of the shooting center 32 of the shooting unit 30 located on the outer periphery are detected. Based on the detected coordinates (X13, Y13), (X14, Y14), and (X15, Y15), the coordinates (X1, Y1) of the center 12 of the chuck worktable 10 are calculated.

[0104] The center positioning method of Embodiment 2 can determine the positional relationship between the imaging unit 30 and the detection unit 40 based on the image 31 captured by the imaging unit 30, the detection results of the detection unit 40, and the detection results of each position detection unit 61, 62, and 63. As a result, similar to Embodiment 1, the center positioning method of Embodiment 1 can easily determine the actual positional relationship between the imaging unit 30 and the detection unit 40.

[0105] [Variation Example]

[0106] The center positioning method of the modified embodiments of Embodiments 1 and 2 of the present invention will be described with reference to the accompanying drawings. Figure 12 This is a perspective view showing a structural example of a processing apparatus implementing the center positioning methods of Embodiment 1 and Embodiment 2. Additionally, in Figure 12 In this document, parts that are the same as those in Embodiment 1 are labeled with the same reference numerals and their descriptions are omitted.

[0107] The center positioning method in the modified example is the same as in embodiment 1, except that it is implemented by the processing device 1-1, wherein, as Figure 12 As shown, the machining device 1-1 is a device that has only one cutting unit 21-1, one Y-axis moving unit 52-1, one Z-axis moving unit 54-1, one Y-axis position detection unit 62-1, and one Z-axis position detection unit 64-1, and the detection unit 40 is disposed in the cutting unit 21-1.

[0108] Figure 12The structure of the cutting unit 21-1 of the processing device 1-1 shown is the same as that of the first cutting unit 21 in Embodiment 1, the structure of the Y-axis moving unit 52-1 is the same as that of the first Y-axis moving unit 52 in Embodiment 1, the structure of the Z-axis moving unit 54-1 is the same as that of the first Z-axis moving unit 54 in Embodiment 1, the structure of the Y-axis position detection unit 62-1 is the same as that of the first Y-axis position detection unit 62 in Embodiment 1, and the structure of the Z-axis position detection unit 64-1 is the same as that of the first Z-axis position detection unit 64 in Embodiment 1.

[0109] Thus, in the modified example, the first Y-axis moving unit 52 and the second Y-axis moving unit 53 are Y-axis moving units 52-1 as a Y-axis moving unit, and the imaging unit 30 and the detection unit 40 are disposed on the machining component, i.e., the cutting unit 21-1, which is connected to the Y-axis moving unit 52-1.

[0110] The modified center positioning method, based on the image 31 captured by the imaging unit 30, the detection results of the detection unit 40, and the detection results of each position detection unit 61, 62, and 63, can determine the positional relationship between the imaging unit 30 and the detection unit 40. As a result, similar to Embodiment 1, the center positioning method of Embodiment 1 achieves the effect of easily determining the actual positional relationship between the imaging unit 30 and the detection unit 40.

[0111] Furthermore, the present invention is not limited to the embodiments described above. That is, various modifications can be made without departing from the spirit of the present invention.

Claims

1. A center positioning method, wherein the detection center of a detection component is positioned at the imaging center of an imaging component in a device, the device comprising: A circular chuck table that holds the workpiece in place; X-axis moving component, which moves the chuck table in the X-axis direction; The imaging component is used to image the workpiece held by the chuck table. A first Y-axis moving component moves the imaging component in the Y-axis direction; The detection component detects the height of the workpiece held by the chuck table; and The second Y-axis moving component moves the detection component in the Y-axis direction. in, The center positioning method comprises the following steps: The first center coordinate detection process involves moving the X-axis moving component and the first Y-axis moving component, and determining the coordinates (X1, Y1) of the center of the chuck table based on the image captured by the imaging component. The second center coordinate detection process involves moving the X-axis moving component and the second Y-axis moving component, and determining the coordinates (X2, Y2) of the center of the chuck table based on the detection result of the detection component. In the coordinate distance calculation process, the X-coordinate of the center of the chuck stage, determined based on the image captured by the imaging component, is set as X1; the X-coordinate of the center of the chuck stage, determined based on the detection result of the detection component, is set as X2; and the distance α between the centers is calculated as (X1-X2). Similarly, the Y-coordinate of the center of the chuck stage, determined based on the image captured by the imaging component, is set as Y1; the Y-coordinate of the center of the chuck stage, determined based on the detection result of the detection component, is set as Y2; and the distance β between the centers is calculated as (Y1-Y2). In the center alignment process, when the imaging center of the imaging component is positioned at the coordinates X0, Y0, the detection center of the detection component is positioned at the coordinates X0-α, Y0-β, so that the imaging center of the imaging component is aligned with the detection center of the detection component.

2. The center positioning method according to claim 1, wherein, The first center coordinate detection process uses an imaging component to photograph a feature point on the outer periphery of the chuck table's center, determining the coordinates (X11, Y11). Then, the chuck table is rotated at any angle to photograph the feature point again, determining its coordinates (X12, Y12). The coordinates of the center of the chuck table (X1, Y12) are then determined by using the coordinates of a point located on a linear function perpendicular to the center of the calculated feature point coordinates (X11, Y11) and (X12, Y12), at a distance half the distance between the two coordinates. The second center coordinate detection process detects the coordinates of more than three points of the detection component located on the outer periphery of the chuck table where the detection result changes drastically. Based on the detected coordinates of more than three points, the coordinates (X2, Y2) of the center of the chuck table are determined.

3. The center positioning method according to claim 1, wherein, The first center coordinate detection process takes pictures of the area including the outer periphery of the chuck table. Based on the captured images, it detects the coordinates of three or more points of the center of the imaging component located on the outer periphery. Based on the detected coordinates of the three or more points, it calculates the coordinates (X1, Y1) of the center of the chuck table. The second center coordinate detection process detects the coordinates of more than three points of the detection component located on the outer periphery of the chuck table where the detection result changes drastically. Based on the detected coordinates of more than three points, the coordinates (X2, Y2) of the center of the chuck table are determined.

4. The center positioning method according to claim 1, wherein, The imaging component is mounted on a first machining component that is connected to the first Y-axis moving component. The detection component is mounted on a second processing component that is connected to the second Y-axis moving component.

5. A center positioning method, wherein the detection center of a detection component is positioned at the imaging center of an imaging component in a device, the device comprising: A circular chuck table that holds the workpiece in place; X-axis moving component, which moves the chuck table in the X-axis direction; The imaging component is used to image the workpiece held by the chuck table. The detection component detects the height of the workpiece held by the chuck table; and A Y-axis moving component is provided, wherein the imaging component and the detection component are disposed on a machining component connected to the Y-axis moving component, and the Y-axis moving component causes the imaging component and the detection component to move in the Y-axis direction. in, The center positioning method comprises the following steps: The first center coordinate detection process involves moving the X-axis moving component and the Y-axis moving component, and determining the coordinates (X1, Y1) of the center of the chuck table based on the image captured by the imaging component. The second center coordinate detection process involves moving the X-axis moving component and the Y-axis moving component, and determining the coordinates (X2, Y2) of the center of the chuck table based on the detection result of the detection component. In the coordinate distance calculation process, the X-coordinate of the center of the chuck stage, determined based on the image captured by the imaging component, is set as X1; the X-coordinate of the center of the chuck stage, determined based on the detection result of the detection component, is set as X2; and the distance α between the centers is calculated as (X1-X2). Similarly, the Y-coordinate of the center of the chuck stage, determined based on the image captured by the imaging component, is set as Y1; the Y-coordinate of the center of the chuck stage, determined based on the detection result of the detection component, is set as Y2; and the distance β between the centers is calculated as (Y1-Y2). In the center alignment process, when the imaging center of the imaging component is positioned at the coordinates X0, Y0, the detection center of the detection component is positioned at the coordinates X0-α, Y0-β, so that the imaging center of the imaging component is aligned with the detection center of the detection component.

Images