Processing device and processing method for a workpiece

Abstract

Provided is a processing device and a processing method for a workpiece, which enable observation of the lower surface side of a workpiece held by a chuck table and which enable downsizing of the device. The processing device includes: a chuck table that holds a workpiece with a holding surface; a processing unit that processes the workpiece held by the chuck table; a moving mechanism that moves the chuck table and the processing unit in opposite directions in a direction parallel to the holding surface of the chuck table; an angle control mechanism that is provided on the moving mechanism and on the lower side of the chuck table and that controls the angle of the chuck table; and a photographing unit that photographs the workpiece held by the chuck table. The chuck table includes a holding member that is composed of a transparent body and that holds the workpiece, and a support member that is connected to the angle control mechanism and that supports a portion of the holding member.

Description

TECHNICAL FIELD

[0001] The present application relates to a processing apparatus that processes a workpiece, and a processing method of a workpiece using the processing apparatus. BACKGROUND

[0002] In a manufacturing process of a device chip, a wafer in which devices such as ICs (Integrated Circuits), LSIs (Large Scale Integrations), and the like are respectively formed in a plurality of regions divided by a division predetermined line (a street) is used. By dividing the wafer along the division predetermined line, a plurality of device chips each having a device are obtained.

[0003] In the division of the wafer, for example, a cutting apparatus is used, which has a chuck table that holds the wafer, and a processing unit (a cutting unit) that is provided with a ring-shaped cutting tool that cuts the wafer held by the chuck table. The wafer is divided into a plurality of device chips by rotating the cutting tool to cut into the wafer.

[0004] In recent years, however, a method of dividing the wafer using a laser processing apparatus is also adopted. The laser processing apparatus has a chuck table that holds the wafer, and a processing unit (a laser irradiation unit) that processes the wafer by irradiating a laser beam toward the wafer held by the chuck table.

[0005] For example, a method is proposed in which a laser beam that is transmissive to the wafer is converged to the inside of the wafer, and a modified region (a modified layer) is formed in the inside of the wafer along the division predetermined line. The region in which the modified layer is formed is brittle compared to other regions of the wafer. Therefore, when an external force is applied to the wafer in which the modified layer is formed, the wafer is divided along the division predetermined line starting from the modified layer.

[0006] When the wafer is processed by the processing apparatus typified by the above-described cutting apparatus or the laser processing apparatus, after the wafer is arranged on the holding surface of the chuck table, the front surface side of the wafer in which the device is formed is imaged by an imaging unit such as a camera, so that the position of the region to be processed (a processed region) of the wafer is detected. Further, based on the position of the processed region detected, alignment that adjusts the positional relationship between the wafer and the processing unit is performed.

[0007] In addition, depending on the content of the processing, sometimes the processing is performed in a state in which the front surface side of the wafer is opposed to the holding surface of the chuck table, and the back surface side of the wafer is exposed upward. In this case, the front surface side (the lower surface side) of the wafer is covered by the holding surface of the chuck table, so it is difficult to image the front surface side of the wafer by the imaging unit. As a result, it is not possible to detect the processed region based on the position of the device formed on the front surface side of the wafer and the like.

[0008] Therefore, a processing apparatus is proposed which enables observation of the front surface side of a wafer even in a state where the front surface side of the wafer on which devices are formed is covered by the holding surface of the chuck table. A cutting apparatus having an infrared lamp which irradiates infrared rays which pass through the wafer is disclosed, for example, in Patent Document 1. In the cutting apparatus, infrared rays which are irradiated from the infrared lamp to the back surface side of the wafer pass through the wafer and reach the front surface side of the wafer. Further, the pattern of the front surface side of the wafer is observed by detecting infrared rays which are reflected from the front surface side of the wafer.

[0009] In addition, a laser processing apparatus is disclosed in Patent Document 2 and Patent Document 3, which has a chuck table which is a transparent member and a photographing unit which is disposed on the lower side of the chuck table. In the laser processing apparatus, even in a case where the front surface side of the wafer is covered by the holding surface of the chuck table, the front surface side of the wafer can be photographed from the lower side of the wafer through the transparent chuck table.

[0010] Patent Document 1: Japanese Patent Application Publication No. H6-232255

[0011] Patent Document 2: Japanese Patent Application Publication No. 2010-82644

[0012] Patent Document 3: Japanese Patent Application Publication No. 2010-87141

[0013] When the above-described cutting apparatus having an infrared lamp is used, even in a case where the front surface side of the wafer is covered by the holding surface of the chuck table, the front surface side (lower surface side) of the wafer can be photographed, and the processed region can be detected in accordance with the position of the devices formed on the front surface side of the wafer. However, in a case where, for example, a layer (metal layer or the like) which does not transmit infrared rays is formed on the back surface side or inside of the wafer, the photographing of the front surface side of the wafer can be hindered.

[0014] On the other hand, in the laser processing apparatus having the transparent chuck table, the photographing unit which is disposed on the lower side of the chuck table photographs the front surface side of the wafer through the chuck table. Therefore, even in a case where a metal layer or the like is formed on the back surface side or inside of the wafer, the devices or the like formed on the front surface side of the wafer can be photographed.

[0015] However, in the laser processing apparatus, a moving mechanism which controls the position in the horizontal direction of the photographing unit is provided, or a rotating mechanism which rotates the chuck table is provided on the side of the chuck table. Therefore, a region in which the moving mechanism or the rotating mechanism is disposed needs to be ensured inside the processing apparatus, and the size of the apparatus increases. SUMMARY

[0016] The present application has been achieved in view of the problem, and has an object to provide a processing apparatus and a processing method of a processed object using the processing apparatus, which can observe the lower surface side of a processed object held by a chuck table and can realize reduction in size of the apparatus.

[0017] According to one embodiment of the present application, there is provided a processing apparatus including: a chuck table that holds a processed object with a holding surface; a processing unit that processes the processed object held by the chuck table; a moving mechanism that relatively moves the chuck table and the processing unit in a direction parallel to the holding surface of the chuck table; an angle control mechanism that is provided on the moving mechanism and on the lower side of the chuck table and controls the angle of the chuck table; and a photographing unit that photographs the processed object held by the chuck table, the chuck table including: a holding member that is composed of a transparent body and holds the processed object; and a support member that is connected to the angle control mechanism and supports a part of the holding member, in a state where the photographing unit is positioned on the lower side of the holding member and does not overlap with the support member by moving the chuck table by the moving mechanism, the processed object is photographed by the photographing unit through the holding member.

[0018] In addition, it is preferable that the angle control mechanism be a rotation mechanism that rotates the chuck table. In addition, it is preferable that the chuck table further include a peripheral holding member that holds the outer periphery of the holding member, the peripheral holding member being supported by the support member. In addition, it is preferable that the processing apparatus further include an upper photographing unit that photographs the processed object held by the chuck table from the upper side of the holding member. In addition, it is preferable that the processing apparatus further include an alignment member on which a target for aligning the photographing unit and the upper photographing unit is attached, the target being photographed by the photographing unit positioned on the lower side of the holding member and the upper photographing unit positioned on the upper side of the holding member. In addition, it is preferable that the processing apparatus further include a moving mechanism that moves the photographing unit in a direction perpendicular to the holding surface of the chuck table.

[0019] Further, according to one embodiment of the present application, there is provided a method of processing a workpiece, the workpiece being processed by a processing apparatus, the processing apparatus including: a chuck table that holds the workpiece by a holding surface; a processing unit that processes the workpiece held by the chuck table; a moving mechanism that relatively moves the chuck table and the processing unit in a direction parallel to the holding surface of the chuck table; an angle control mechanism that is provided on the moving mechanism and on a lower side of the chuck table and controls an angle of the chuck table; and a photographing unit that photographs the workpiece held by the chuck table, the chuck table including: a holding member that is composed of a transparent body and holds the workpiece; and a support member that is connected to the angle control mechanism and supports a part of the holding member, the method of processing the workpiece including: a tape attaching step of attaching a tape to a front side of the workpiece; a holding step of holding the workpiece through the tape by the chuck table after the tape attaching step; a determining step of determining a region to be processed of the workpiece by photographing the front side of the workpiece through the holding member using the photographing unit positioned on a lower side of the holding member and not overlapping with the support member after the holding step; a processing step of cutting the workpiece along the region to be processed by the processing unit after the determining step; a detecting step of detecting a difference between a position of the region to be processed and a position of a processing mark formed in the processing step by photographing the front side of the workpiece through the holding member using the photographing unit positioned on the lower side of the holding member and not overlapping with the support member after the processing step; and a position correcting step of correcting a position to be processed by the processing unit according to the difference between the position of the region to be processed and the position of the processing mark.

[0020] According to one aspect of the present invention, a method for processing a workpiece is provided, wherein a processing apparatus is used to process the workpiece, the processing apparatus comprising: a chuck table holding the workpiece using a holding surface; a processing unit processing the workpiece held by the chuck table; a moving mechanism moving the chuck table and the processing unit relative to each other in a direction parallel to the holding surface of the chuck table; an angle control mechanism disposed on the moving mechanism and below the chuck table for controlling the angle of the chuck table; and a first imaging unit and a second imaging unit for processing the workpiece held by the chuck table. The chuck table includes: a holding member made of a transparent body for holding the workpiece; and a support member connected to the angle control mechanism for supporting a portion of the holding member. The processing method of the workpiece includes the following steps: a holding step in which the workpiece is held by the chuck table with its front side facing the upper surface of the holding member; and a determination step in which, after the holding step, a first imaging unit located on the lower side of the holding member and not overlapping with the support member is used to capture images of the front side of the workpiece through the holding member to determine the area of ​​the workpiece to be processed.

[0021] The processing steps include: a processing step, after the determination step, forming a processing groove on the back side of the workpiece along the area to be processed by the processing unit; a detection step, after the processing step, taking a picture of the processing groove using the second imaging unit positioned above the holding member, and detecting the difference between the position of the area to be processed and the position of the processing groove; and a position correction step, correcting the position to be processed by the processing unit based on the difference between the position of the area to be processed and the position of the processing groove.

[0022] One aspect of the processing apparatus of the present invention enables the imaging unit to photograph the workpiece over the holding member while the imaging unit is positioned below the holding member and does not overlap with the support member by moving the chuck table via a moving mechanism. Therefore, the imaging unit and the holding member can be aligned without the need for a separate moving mechanism for moving the imaging unit horizontally, thus enabling a miniaturization of the processing apparatus. Furthermore, in the above-described processing apparatus, the angle control mechanism is located below the chuck table, thus reducing the overall area of ​​the processing apparatus compared to configurations where the angle control mechanism is located to the side of the chuck table. Attached Figure Description

[0023] Figure 1 This is a three-dimensional view showing a laser processing device.

[0024] Figure 2(A) is a perspective view showing a workpiece, Figure 2 (B) is a perspective view showing a workpiece supported to a frame.

[0025] Figure 3 (A) is a plan view showing a chuck table, Figure 3 (B) is a partially cutaway side view showing a chuck table.

[0026] Figure 4 (A) is a plan view showing a chuck table, Figure 4 (B) is a partially cutaway side view showing a chuck table.

[0027] Figure 5 is a partially cutaway side view showing a chuck table on which a positioning member is mounted.

[0028] Figure 6 (A) is a partially cutaway side view showing a workpiece held by a chuck table, Figure 6 (B) is an image view showing an image acquired by a photographing unit.

[0029] Figure 7 (A) is a partially cutaway side view showing a workpiece held by a chuck table, Figure 7 (B) is an image view showing an image acquired by a photographing unit.

[0030] Figure 8 (A) is a plan view showing a back surface side of a workpiece photographed by a photographing unit, Figure 8 (B) is a bottom view showing a front surface side of a workpiece photographed by a photographing unit, Figure 8 (C) is a bottom view showing a front surface side of a workpiece processed along a division predetermined line.

[0031] Figure 9 (A) is a bottom view showing a front surface side of a workpiece photographed by a photographing unit in a first outer peripheral region, Figure 9 (B) is a bottom view showing a front surface side of a workpiece photographed by a photographing unit in a second outer peripheral region.

[0032] Explanation of Reference Signs

[0033] 11: workpiece; 11a: front surface; 11b: back surface; 11c: processing mark (cutting groove); 11d: processing groove; 13: division intended line (interval groove); 15: device; 17: tape; 19: frame; 19a: opening; 21: pattern layer (functional layer); 23: metal layer; 2: laser processing apparatus; 4: base; 4a: front surface (upper surface); 6: support structure; 8: moving mechanism (moving unit); 10: Y-axis guide rail; 12: Y-axis moving table; 14: Y-axis ball screw; 16: Y-axis pulse motor; 18: X-axis guide rail; 20: X-axis moving table; 22: X-axis ball screw; 24: X-axis pulse motor; 26: chuck table (holding table); 26a: holding surface; 28: angle control mechanism (angle control unit); 30: support arm; 32: processing unit (laser irradiation unit); 34: moving mechanism (moving unit); 36: Z-axis guide rail; 38: Z-axis moving plate; 40: Z-axis ball screw; 42: Z-axis pulse motor; 44: support arm; 46: imaging unit (lower imaging unit, first imaging unit); 46a: low magnification camera; 46b: high magnification camera; 48: imaging unit (upper imaging unit, second imaging unit); 50: control section (control unit); 60: holding member; 60a: upper surface; 60b: lower surface; 60c: recessed portion; 62: support member; 64: porous member; 66: valve; 68: suction source; 70: region; 80: chuck table (holding table); 82: holding member; 82a: upper surface; 82b: lower surface; 82c: recessed portion; 84: peripheral holding member; 86: upper member; 86a: upper surface; 86b: lower surface; 86c: opening; 86d: suction hole; 88: lower member; 88a: upper surface; 88b: lower surface; 88c: opening; 88d: support portion; 88e: recessed portion; 90: support member; 90a: upper surface; 92: porous member; 94a, 94b, 94c: valve; 96a, 96b, 96c: suction source; 98: region; 110: alignment member; 110a: upper surface; 110b: lower surface; 112: target (alignment mark); 114: connecting member; 120, 122, 124: image; 130: peripheral region; 132: target (alignment mark); 134: peripheral region; 136a: first peripheral region; 136b: second peripheral region. DETAILED DESCRIPTION

[0034] Hereinafter, an embodiment of one mode of the present application will be described with reference to the drawings. Figure 1 is a perspective view showing a structure example of a laser processing apparatus 2 as a processing apparatus of the present embodiment.

[0035] The laser processing apparatus 2 has a base 4 that supports each of the components that make up the laser processing apparatus 2. The front surface (upper surface) 4a of the base 4 is formed substantially parallel to the X-axis direction (first horizontal direction) and the Y-axis direction (second horizontal direction). In addition, a cuboid-shaped support structure 6 is disposed in the rear of the base 4 in the Z-axis direction (vertical direction, up-down direction).

[0036] A moving mechanism (moving unit) 8 is provided on the front surface 4a of the base 4. The moving mechanism 8 has a pair of Y-axis rails 10 disposed substantially parallel to the Y-axis direction. A Y-axis moving table 12 is installed on the pair of Y-axis rails 10 in a state in which it is able to slide along the Y-axis rails 10.

[0037] A nut portion (not shown) is provided on the back surface (lower surface) side of the Y-axis moving table 12. A Y-axis ball screw 14 is screwed into the nut portion, the Y-axis ball screw 14 being disposed substantially parallel to the pair of Y-axis rails 10. In addition, a Y-axis pulse motor 16 is connected to one end of the Y-axis ball screw 14. When the Y-axis ball screw 14 is rotated by the Y-axis pulse motor 16, the Y-axis moving table 12 moves in the Y-axis direction along the pair of Y-axis rails 10.

[0038] A pair of X-axis rails 18 is disposed on the front surface (upper surface) side of the Y-axis moving table 12 substantially parallel to the X-axis direction. An X-axis moving table 20 is installed on the pair of X-axis rails 18 in a state in which it is able to slide along the X-axis rails 18.

[0039] A nut portion (not shown) is provided on the back surface (lower surface) side of the X-axis moving table 20. An X-axis ball screw 22 is screwed into the nut portion, the X-axis ball screw 22 being disposed substantially parallel to the pair of X-axis rails 18. In addition, an X-axis pulse motor 24 is connected to one end of the X-axis ball screw 22. When the X-axis ball screw 22 is rotated by the X-axis pulse motor 24, the X-axis moving table 20 moves in the X-axis direction along the pair of X-axis rails 18.

[0040] A chuck table (holding table) 26 that holds the workpiece 11 (refer to (A) of FIG. 1) is disposed on the front surface (upper surface) side of the X-axis moving table 20. The upper surface of the chuck table 26 constitutes a holding surface 26a that holds the workpiece 11. The holding surface 26a is connected to a suction source (not shown) via a suction path (not shown) formed in the interior of the chuck table 26. In a state in which the workpiece 11 is disposed on the holding surface 26a of the chuck table 26, negative pressure of the suction source is applied to the holding surface 26a, and thus the workpiece 11 is held by suction by the chuck table 26. Figure 2

[0041] Figure 2 ​(A) is a perspective view showing the workpiece 11. The workpiece 11 is, for example, a wafer formed from silicon or the like and shaped into a disk shape, having a front side 11a and a back side 11b. The workpiece 11 is divided into multiple regions by predetermined dividing lines (spacers) 13 arranged in a grid pattern in an intersecting manner, and devices 15 such as ICs (Integrated Circuits), LSIs (Large Scale Integrations), and LEDs (Light Emitting Diodes) are formed on the front side 11a of these regions, respectively.

[0042] Furthermore, there are no restrictions on the material, shape, structure, or size of the workpiece 11. For example, the workpiece 11 can be a wafer of any shape and size formed from materials other than silicon, such as semiconductors (GaAs, InP, GaN, SiC, etc.), sapphire, glass, ceramics, resin, or metal. Additionally, there are no restrictions on the type, quantity, shape, structure, size, or arrangement of the devices 15.

[0043] In addition, for ease of processing or transport, the workpiece 11 can be supported by a ring-shaped frame. Figure 2 (B) is a perspective view showing the workpiece 11 supported on a ring-shaped frame 19. A circular strip 17 with a diameter larger than that of the workpiece 11 is attached to the front 11a side of the workpiece 11. Thus, the front 11a side of the workpiece 11 is covered by the strip 17, and multiple devices 15 are protected by the strip 17.

[0044] Furthermore, there are no restrictions on the materials with the 17 designation. For example, the 17 designation is a flexible film obtained by forming a rubber-based or acrylic adhesive layer (paste layer) on a substrate made of resins such as polyolefins, polyvinyl chloride, and polyethylene terephthalate.

[0045] The outer periphery of the belt 17 is attached to the annular frame 19, which has a circular opening 19a at its center with a diameter larger than that of the workpiece 11. Thus, the workpiece 11 is supported by the frame 19 by means of the belt 17 while positioned inside the opening 19a.

[0046] like Figure 1 As shown, an angle control mechanism (angle control unit) 28 is provided on the lower side of the chuck table 26 to control the angle of the chuck table 26 in the horizontal direction (XY plane direction). The angle control mechanism 28 is provided on the X-axis moving stage 20 of the moving mechanism 8, and the lower end of the chuck table 26 is connected to the angle control mechanism 28.

[0047] The angle control mechanism 28 is constituted by a rotation mechanism (rotation unit) that rotates the chuck table 26, for example. The rotation mechanism has a rotation drive source such as a motor, and rotates the chuck table 26 about a rotation axis that is substantially parallel to the Z-axis direction. Thereby, the angle of the chuck table 26 in the horizontal direction is controlled.

[0048] The movement mechanism 8 controls the positions of the chuck table 26 and the angle control mechanism 28 in a direction (horizontal direction) parallel to the holding surface 26a of the chuck table 26. Specifically, when the X-axis moving stage 20 is moved in the X-axis direction, the chuck table 26 and the angle control mechanism 28 are moved in the X-axis direction. In addition, when the Y-axis moving stage 12 is moved in the Y-axis direction, the chuck table 26 and the angle control mechanism 28 are moved in the Y-axis direction.

[0049] In addition, in the movement mechanism 8, an X-axis detection unit (not shown) that detects the position of the X-axis moving stage 20 in the X-axis direction, and a Y-axis detection unit (not shown) that detects the position of the Y-axis moving stage 12 in the Y-axis direction are provided. The position of the chuck table 26 in the horizontal direction is determined by the X-axis detection unit and the Y-axis detection unit.

[0050] In addition, the laser processing apparatus 2 has a columnar support arm 30 that protrudes toward the front from the front surface side of the support structure 6. A processing unit (laser irradiation unit) 32 that irradiates a laser beam to the workpiece 11 held by the chuck table 26 to process the workpiece 11 is disposed at the front end portion of the support arm 30. The processing unit 32 has a laser oscillator (not shown) such as a YAG laser, a YVO4 laser, and a condenser (not shown) that condenses the laser beam oscillated from the laser oscillator.

[0051] In addition, the wavelength of the laser beam irradiated from the processing unit 32 is not limited, and is appropriately set according to the purpose of the laser processing. For example, when performing ablation processing on the workpiece 11, the wavelength of the laser beam is set in such a manner that at least a part of the laser beam is absorbed by the workpiece 11. In this case, a laser beam having absorbency with respect to the workpiece 11 is irradiated. In addition, the condenser condenses the laser beam oscillated from the laser oscillator to a prescribed position of the workpiece 11 held by the chuck table 26.

[0052] In a state where the workpiece 11 is held by the chuck table 26, a laser beam is irradiated toward the chuck table 26 from the machining unit 32, and thus laser machining is performed on the workpiece 11. In addition, the movement and the angle of the chuck table 26 at the time of irradiating the laser beam are controlled in accordance with the shape of the region (machined region) of the workpiece 11 to be machined. Specifically, the movement mechanism 8 relatively moves the chuck table 26 and the machining unit 32 in a direction parallel to the holding surface 26a of the chuck table 26. In addition, the angle control mechanism 28, for example, rotates the chuck table 26, and thus adjusts the angle of the chuck table 26.

[0053] The workpiece 11 is, for example, divided along the division predetermined line 13 by using the machining unit 32 for ablation machining. In this case, a machining mark (cut groove) 11c (refer to (A) of FIG. 10) from the front surface 11a to the back surface 11b is formed on the workpiece 11 along the division predetermined line 13. In addition, by the ablation machining, a machining groove 11d (refer to (A) of FIG. 11) having a depth smaller than the thickness of the workpiece 11 can also be formed on the back surface 11b side of the workpiece 11 along the division predetermined line 13. Figure 6 Figure 7

[0054] In addition, a movement mechanism (movement unit) 34 fixed to the front surface side of the support structure 6 is provided below the support arm 30. The movement mechanism 34 has a pair of Z-axis rails 36 disposed substantially in parallel to the Z-axis direction, and a plate-shaped Z-axis moving plate 38 is installed in a slidable state on the pair of Z-axis rails 36.

[0055] A nut portion (not shown) is provided on the rear surface side (back surface side) of the Z-axis moving plate 38. A Z-axis ball screw 40 disposed substantially in parallel to the pair of Z-axis rails 36 is screwed into the nut portion. A Z-axis pulse motor 42 is connected to one end portion of the Z-axis ball screw 40. When the Z-axis ball screw 40 is rotated by the Z-axis pulse motor 42, the Z-axis moving plate 38 moves in the Z-axis direction along the pair of Z-axis rails 36.

[0056] A columnar support arm 44 protruding forward from the Z-axis moving plate 38 is fixed to the front surface side (front surface side) of the Z-axis moving plate 38. In addition, a photographing unit (lower photographing unit, first photographing unit) 46 photographing the workpiece 11 held by the chuck table 26 from the lower side is provided on the upper surface side of the front end portion (front end portion) of the support arm 44.

[0057] In Figure 1 ​​An example of the photographing unit 46 composed of the low magnification camera 46a and the high magnification camera 46b is shown in FIG. 6. The photographing unit 46 can perform photographing using one of the low magnification camera 46a and the high magnification camera 46b, or can perform photographing using both of them. The low magnification camera 46a and the high magnification camera 46b are composed of, for example, a visible light camera or an infrared camera, or the like, respectively.

[0058] The moving mechanism 34 moves the photographing unit 46 in the direction perpendicular to the holding surface 26a of the chuck table 26 (Z-axis direction). Thereby, the height (position in the Z-axis direction) of the photographing unit 46 is controlled.

[0059] In addition, a photographing unit (upper photographing unit, second photographing unit) 48 that photographs the workpiece 11 held by the chuck table 26 from the upper side is provided at a position adjacent to the processing unit 32 at the front end of the support arm 30. The photographing unit 48 is composed of, for example, a visible light camera or an infrared camera, or the like.

[0060] In addition, the support arm 30 can be connected to a moving mechanism (not shown) that moves the support arm 30 in the horizontal direction or the vertical direction. In this case, the positions of the processing unit 32 and the photographing unit 48 are controlled by the moving mechanism.

[0061] In addition, the laser processing apparatus 2 has a control section (control unit) 50 that controls the operation of each of the constituent elements that constitute the laser processing apparatus 2. The constituent elements (the moving mechanism 8, the chuck table 26, the angle control mechanism 28, the processing unit 32, the moving mechanism 34, the photographing unit 46, the photographing unit 48, and the like) of the laser processing apparatus 2 are connected to the control section 50, respectively, and their operations are controlled by the control section 50.

[0062] The laser processing apparatus 2 performs the alignment of the workpiece 11 and the processing unit 32 by the photographing unit 46 disposed at the lower side of the chuck table 26 photographing the workpiece 11. In addition, the chuck table 26 is configured to be able to perform photographing of the workpiece 11 by the photographing unit 46 disposed at the lower side of the chuck table 26.

[0063] Figure 3 (A) of FIG. 6 is a plan view showing the chuck table 26, Figure 3 (B) of FIG. 6 is a partially cutaway side view showing the chuck table 26. In addition, the workpiece 11 held by the chuck table 26 is also shown in (B) of FIG. 6. Figure 3

[0064] ​The chuck table 26 has a disc-shaped holding member 60 made of a transparent body that holds the workpiece 11, and a cylindrical support member 62 that supports the holding member 60 from the lower side. The support member 62 protrudes downward from the central portion of the holding member 60, and the lower end side of the support member 62 is connected to the angle control mechanism 28. In addition, the holding member 60 and the support member 62 are, for example, arranged in a top view as concentric circles.

[0065] The holding member 60 has an upper surface 60a and a lower surface 60b that are formed substantially parallel to each other. The upper surface 60a of the holding member 60 corresponds to the holding surface 26a (see FIG. 1) of the chuck table 26. The lower surface 60b of the holding member 60 is connected to the upper end side of the support member 62. When the support member 62 is rotated by the angle control mechanism 28, the holding member 60 rotates around an axis of rotation that is substantially parallel to the Z-axis direction. Figure 1 ) The lower surface 60b of the holding member 60 is connected to the upper end side of the support member 62. When the support member 62 is rotated by the angle control mechanism 28, the holding member 60 rotates around an axis of rotation that is substantially parallel to the Z-axis direction.

[0066] A recess 60c in the shape of a circle in a top view is formed in the central portion of the upper surface 60a side of the holding member 60. A porous member 64 made of porous ceramics or the like is fitted in this recess 60c. In addition, the recess 60c is connected to a suction source 68 via a suction passage and a valve 66 provided inside the holding member 60, the support member 62, and the angle control mechanism 28.

[0067] The workpiece 11 is, for example, arranged on the holding member 60 in a manner such that the front surface 11a side faces the upper surface 60a of the holding member 60, and the back surface 11b side is exposed upward. In addition, when the front surface 11a side of the workpiece 11 on which the device 15 (see (A) of FIG. 1) is formed is held by the chuck table 26, a protective member (protective sheet) made of resin or the like can be attached to the front surface 11a side of the workpiece 11. Thus, the front surface 11a side of the workpiece 11 is covered with the protective member, and the device 15 is protected. Figure 2

[0068] When the valve 66 is opened in a state in which the workpiece 11 is arranged on the holding member 60, a negative pressure is applied to the upper surface 60a side of the holding member 60 via the porous member 64, and the workpiece 11 is suction-held by the chuck table 26. In Figure 3 (A) and Figure 3 (B), an example in which the holding member 60 is formed in the shape of a circle in a top view in correspondence with the shape of the workpiece 11 is shown, but the shape of the holding member 60 can be appropriately changed in accordance with the shape of the workpiece 11.

[0069] Here, the diameter of the support member 62 is smaller than the diameter of the holding member 60. Therefore, a region 70 that overlaps with the holding member 60 and does not overlap with the support member 62 is formed below the holding member 60. In Figure 3 ​As shown in (B) of FIG. 6, the region 70 is formed around the support member 62 so as to at least overlap the outer peripheral portion of the workpiece 11.

[0070] The position of the chuck table 26 and the angle control mechanism 28 is controlled by the moving mechanism 8 (refer to Figure 1 ) so as to dispose the imaging unit 46 in the region 70. Then, the workpiece 11 is imaged by the imaging unit 46 through the holding member 60. As shown in (B) of FIG. 6, in a case where the front surface 11a side of the workpiece 11 opposes the upper surface 60a of the holding member 60, the front surface 11a side of the workpiece 11 is imaged by the imaging unit 46. Figure 3

[0071] When the workpiece 11 is imaged by the imaging unit 46, the imaging unit 46 is moved in the vertical direction by the moving mechanism 34 so as to adjust the distance between the imaging unit 46 and the workpiece 11. Thus, the imaging unit 46 is focused, and a clear image can be obtained.

[0072] In addition, the material of the holding member 60 is appropriately selected according to the kind of the imaging unit 46. For example, in a case where the imaging unit 46 is constituted by a visible light camera, the holding member 60 is constituted by a member that transmits visible light. In addition, in a case where the imaging unit 46 is constituted by an infrared camera, the holding member 60 is constituted by a member that transmits infrared light. As a specific example of the material of the holding member 60, there are quartz glass, borosilicate glass, sapphire, calcium fluoride, lithium fluoride, magnesium fluoride, and the like.

[0073] As described above, the workpiece 11 is imaged by the imaging unit 46 through the holding member 60 from the lower side of the holding member 60, so that the front surface 11a side of the workpiece 11 covered by the upper surface 60a of the holding member 60 can be imaged. Thus, for example, in a case where a metal layer or the like is formed on the back surface 11b side or the inside of the workpiece 11, the front surface 11a side of the workpiece 11 can also be observed.

[0074] In addition, the upper surface 60a side of the holding member 60 can be formed in a pear skin shape having irregularities. Or a fine groove that is connected to the recess 60c can be formed on the upper surface 60a side of the holding member 60. In this case, when the workpiece 11 is disposed on the holding member 60, a gap is formed between the workpiece 11 and the upper surface 60a of the holding member 60, and the negative pressure of the suction source 68 acts on the entire front surface 11a side of the workpiece 11 through the gap. Thus, the workpiece 11 can be reliably sucked by the chuck table 26.

[0075] ​However, the concave-convex and the groove described above can not be formed on the entire upper surface 60a side of the holding member 60. That is, the holding member 60 can have a region (flat region) on which the concave-convex and the groove described above are not formed. The flat region is provided in a band shape, for example, from the center of the holding member 60 toward the outer periphery. More specifically, four band-shaped flat regions are provided substantially at equal intervals along the circumferential direction of the holding member 60 (cross shape in plan view).

[0076] When the front surface 11a side of the workpiece 11 is imaged by the imaging unit 46, the imaging unit 46 is positioned in a manner so as to overlap the flat region of the holding member 60. Thereby, when the workpiece 11 is imaged by the imaging unit 46 through the holding member 60, it is possible to prevent the imaging from being hindered by the concave-convex or the fine groove, and it is possible to acquire a clear image.

[0077] In addition, in a region in which the support member 62 is provided, the imaging unit 46 cannot be disposed, and it is difficult to image the region of the workpiece 11 overlapping the support member 62 by the imaging unit 46. Therefore, the concave-convex and the groove can be formed in the region of the holding member 60 overlapping the support member 62 without providing the flat region. In this case, the region of the workpiece 11 overlapping the support member 62 is reliably attracted. For example, the band-shaped flat region along the first direction (for example, the X-axis direction) and the band-shaped flat region along the second direction (for example, the Y-axis direction) intersecting the first direction can be provided on the holding member 60 in a manner so as not to overlap the support member 62.

[0078] In addition, when the workpiece 11 is imaged by the imaging unit 46, the chuck table 26 is moved by the moving mechanism 8 (refer to Figure 1 ), and thereby the imaging unit 46 can be positioned in the region 70. Therefore, it is possible to perform the alignment of the imaging unit 46 and the holding member 60 without additionally providing a moving mechanism for moving the imaging unit 46 in the horizontal direction, and thereby it is possible to realize the downsizing of the laser processing apparatus 2.

[0079] In addition, in the laser processing apparatus 2, as shown in (B) of Figure 2 , the angle control mechanism 28 is disposed so as to overlap the chuck table 26 on the lower side of the chuck table 26. Therefore, compared to a case in which a rotating mechanism that rotates the chuck table 26 is provided on the side of the chuck table 26, or the like, the setting area of the laser processing apparatus 2 is downsized.

[0080] In addition, the configuration of the chuck table 26 can be appropriately changed within a range in which the workpiece 11 can be imaged by the imaging unit 46. Figure 4 (A) of FIG. 8 is a plan view showing a chuck table (holding table) 80, Figure 4(A) is a partial cross-sectional side view showing a chuck table 80. This chuck table 80 can also be used in the laser processing apparatus 2 instead of the chuck table 26 shown in (B) of FIG. 6. Figure 3 (A) and Figure 3 (B) of FIG. 6.

[0081] The chuck table 80 has a disc-shaped holding member 82 made of a transparent body that holds the workpiece 11, an outer peripheral holding member 84 that holds at least an outer peripheral portion of the holding member 82, and a support member 90 that supports the outer peripheral holding member 84 from the lower side.

[0082] The holding member 82 has an upper surface 82a and a lower surface 82b, and a recessed portion 82c formed in a central portion on the upper surface 82a side, and a porous member 92 is embedded in the recessed portion 82c. In addition, the shape, material, and the like of the holding member 82 are the same as those of the holding member 60 of the chuck table 26 (refer to (A) and (B) of FIG. 6). Figure 3 (A) and Figure 3 (B) of FIG. 6). The recessed portion 82c of the holding member 82 is connected to a suction source 96a via a suction passage formed in the inner portions of the outer peripheral holding member 84, the support member 90, and the angle control mechanism 28, and a valve 94a.

[0083] The outer peripheral holding member 84 has an annular upper member 86, and an annular lower member 88 that is formed to have substantially the same diameter as the upper member 86 and is disposed on the lower side of the upper member 86. In addition, the upper member 86 and the lower member 88 can be integrally formed, or can be separately formed.

[0084] The upper member 86 has an opening 86c that penetrates the upper member 86 from an upper surface 86a to a lower surface 86b. The opening 86c is formed to be able to accommodate the holding member 82 inside, and is, for example, formed in a circular shape having substantially the same diameter as the holding member 82. In addition, the thickness of the upper member 86 is set to be substantially the same as the thickness of the holding member 82.

[0085] The lower member 88 has an opening 88c that penetrates the lower member 88 from an upper surface 88a to a lower surface 88b. The diameter of the opening 88c is set to be smaller than the diameter of the holding member 82 and the diameter of the opening 86c of the upper member 86. In addition, the lower member 88 has a plate-shaped support portion 88d from the outer peripheral portion to the central portion of the lower member 88. For example, the support portion 88d is formed in a planar fan shape in a manner that the width thereof narrows from the outer peripheral portion toward the central portion of the lower member 88.

[0086] The support member 90 is connected to the lower surface 88b side of the lower member 88, and supports at least a portion of the outer peripheral portion of the outer peripheral holding member 84 (lower member 88). For example, the upper surface 90a of the support member 90 is formed in a sector shape corresponding to the lower surface of the support portion 88d of the lower member 88, and the support member 90 supports a sector-shaped region from the center to the outer peripheral portion of the outer peripheral holding member 84 (lower member 88).

[0087] The lower end side of the support member 90 is connected to the angle control mechanism 28. In addition, the support member 90 is formed in a shape in which the width (diameter) decreases from the upper surface 90a side toward the lower side. In addition, the support member 90 is formed in a shape in which the thickness (length in the height direction) increases from the outer peripheral portion toward the center portion.

[0088] In addition, the suction hole 86d that is annular and penetrates the upper member 86 in the up-down direction is formed in the outer peripheral portion of the upper member 86 (region in which the opening 86c is not formed). The suction hole 86d is connected to the suction source 96b via a suction passage formed in the inside of the lower member 88, the support member 90, and the angle control mechanism 28, and the valve 94b. In addition, a plurality of recesses 88e are formed in the upper surface 88a side of the support portion 88d of the lower member 88. The recesses 88e are connected to the suction source 96c via a suction passage formed in the lower member 88, the support member 90, and the angle control mechanism 28, and the valve 94c.

[0089] When the valve 94c is opened in a state in which the holding member 82 is fitted into the opening 86c of the upper member 86, the negative pressure of the suction source 96c acts on the lower surface 82b side of the holding member 82. Thus, the holding member 82 is held by the outer peripheral holding member 84 in a state in which at least the outer peripheral portion is supported by the upper surface 88a of the lower member 88. In addition, when the support member 90 is rotated by the angle control mechanism 28, the holding member 82 and the outer peripheral holding member 84 are rotated around the rotation axis that is substantially parallel to the Z-axis direction.

[0090] In addition, when the holding member 82 is held by the outer peripheral holding member 84, the support portion 88d overlaps a portion of the holding member 82, and supports the holding member 82. In addition, a portion of the lower surface 82b side of the holding member 82 is exposed downward via the opening 88c of the lower member 88.

[0091] The chuck table 80 holds the workpiece 11 (refer to Figure 2The processed object 11 is arranged on the holding member 82 in a manner that the front surface 11a side (the tape 17 side) opposes the upper surface 82a of the holding member 82 and the back surface 11b side is exposed upward, for example. At this time, the processed object 11 overlaps the recessed portion 82c of the holding member 82 through the tape 17, and the frame 19 overlaps the suction hole 86d of the upper member 86 through the tape 17.

[0092] When the valves 94a and 94b are opened in this state, the negative pressure of the suction sources 96a and 96b acts on the tape 17. Thus, the processed object 11 and the frame 19 are suction-held by the chuck table 80 through the tape 17.

[0093] In addition, a region 98 that overlaps the holding member 82 and does not overlap the support member 90 is formed below the holding member 82. Also, the shooting unit 46 is arranged in the region 98 by controlling the positions of the chuck table 80 and the angle control mechanism 28 with the moving mechanism 8 (refer to Figure 1 ).

[0094] The front surface 11a side of the outer peripheral portion of the processed object 11 is shot by the shooting unit 46, for example. Also, the control section 50 (refer to Figure 1 ) performs the alignment of the processed object 11 held by the chuck table 26 or the chuck table 80 and the processing unit 32 based on the image acquired by the shooting unit 46.

[0095] In addition, as shown in Figure 1 , the laser processing apparatus 2 has the shooting unit 48 in addition to the shooting unit 46. The alignment of the processed object 11 and the processing unit 32 can also be performed using both the shooting unit 46 and the shooting unit 48. In the case where the alignment is performed using the shooting unit 46 and the shooting unit 48, the alignment of the shooting unit 46 and the shooting unit 48 is performed first.

[0096] The alignment of the shooting unit 46 and the shooting unit 48 is performed by making the position in the horizontal direction (the XY plane direction) of the region shot by the shooting unit 46 coincide with the position in the horizontal direction of the region shot by the shooting unit 48. In the alignment of the shooting unit 46 and the shooting unit 48, an alignment member to which an alignment target (an alignment mark) is attached can be used, for example.

[0097] Figure 5 is a partial cross-sectional side view showing the chuck table 26 to which the alignment member 110 is attached. In Figure 5 , the alignment member 110 is attached to the chuck table 26 by means of the connecting member 114.

[0098] The alignment member 110 is, for example, a rectangular parallelepiped-shaped transparent body fixed to the side of the holding member 60. The material of the alignment member 110 is, for example, the same as that of the holding member 60. A target (alignment mark) 112 as a mark for alignment of the imaging units 46 and 48 is attached to the upper surface 110a side of the alignment member 110. The target 112 can be imaged by the imaging units 46 and 48, and is, for example, a colored region on the upper surface 110a side of the alignment member 110.

[0099] In addition, the method of attaching the target 112 is not limited as long as the target 112 can be imaged by the imaging units 46 and 48. For example, the target 112 can be a member composed of metal or the like formed on the upper surface 110a side of the alignment member 110, or a through-hole penetrating the upper surface 110a to the lower surface 110b of the alignment member 110. In addition, the target 112 can be attached to the upper surface 110a side and the lower surface 110b side of the alignment member 110 in a manner of overlapping each other.

[0100] The target 112 is imaged by the imaging unit 46 from the lower side, and by the imaging unit 48 from the upper side. Then, the alignment of the imaging units 46 and 48 is performed in a manner that the position of the target 112 displayed in the image acquired by the imaging unit 46 coincides with the position of the target 112 displayed in the image acquired by the imaging unit 48. This alignment is performed by, for example, the control section 50 of the laser processing apparatus 2 (refer to Figure 1 ).

[0101] The alignment of the imaging units 46 and 48 can be performed by adjusting the position of the imaging unit 48 using a moving mechanism (not shown) connected to the imaging unit 48, or by controlling the optical systems of the imaging units 46 and 48. In addition, this alignment can be performed on software. In this case, for example, the coordinates of the image acquired by the imaging unit 46 and the coordinates of the image acquired by the imaging unit 48 are corrected according to the amount of shift of the position of the target 112.

[0102] Next, a specific example of a processing method of the workpiece 11 using the laser processing apparatus 2 will be described. Hereinafter, a processing of cutting and dividing the workpiece 11 by irradiation of a laser beam will be described.

[0103] First, a tape 17 is attached to the front surface 11a side of the workpiece 11 (refer to (B) of Figure 2 ) (tape attaching step). Next, the workpiece 11 is held by the chuck table 26 through the tape 17 (holding step). Figure 6 (A) of

[0104] In the holding step, the work 11 is arranged on the chuck table 26 in a manner that the front surface 11a side opposes the upper surface 60a of the holding member 60 and the back surface 11b side is exposed upward. In addition, a pattern layer (functional layer) 21 including various functional films (conductive film, insulating film, etc.) that constitute the plurality of devices 15 (refer to (B) of FIG. 6) is formed on the front surface 11a side of the work 11. In addition, the work 11 in which the metal layer 23 is formed on the back surface 11b side is shown in (A) of FIG. 6. Figure 2 Figure 6

[0105] Next, the front surface 11a side of the work 11 is imaged through the holding member 60 by the imaging unit 46 positioned in a region of the holding member 60 that does not overlap the support member 62 (determination step). In the determination step, first, the imaging unit 46 is positioned by the moving mechanism 34 (refer to FIG. 3, etc.) to a position lower than the support member 62. Then, the chuck table 26 and the angle control mechanism 28 are moved in the horizontal direction by the moving mechanism 8 (refer to FIG. 3, etc.) to position the imaging unit 46 at a position overlapping the holding member 60 and not overlapping the support member 62. Figure 1 Figure 1

[0106] Next, the front surface 11a side of the work 11 is imaged through the holding member 60 by the imaging unit 46. Thereby, for example, an enlarged image of the division intended line 13 and the device 15 (refer to (B) of FIG. 6) is acquired. From this image, the region of the work 11 to be processed by the processing unit 32 (refer to FIG. 3, etc.) is determined. This region is set, for example, along the center of the division intended line 13. Figure 2 Figure 1

[0107] Next, the work 11 is cut along the region to be processed (processed region) by the processing unit 32 (processing step). In the processing step, first, the length direction of the division intended line 13 of the work 11 is aligned with the X-axis direction. In addition, the positional relationship of the processing unit 32 and the chuck table 26 is adjusted in a manner that a laser beam is irradiated to the processed region of the work 11. Then, the chuck table 26 is moved in the X-axis direction while irradiating the laser beam from the processing unit 32 to the back surface 11b side of the work 11. Thereby, the laser beam is irradiated along the division intended line 13.

[0108] In addition, the irradiation conditions (position of the focal point, power, spot diameter, repetition frequency, number of irradiations, etc.) of the laser beam are set to be able to cut the work 11 along the division intended line 13. As a result, a processing mark (cut groove) 11c from the back surface 11b to the front surface 11a of the work 11 is formed on the work 11. ​​​​​​

[0109] Next, the front surface 11a side of the work 11 is imaged by the imaging unit 46 positioned in a region of the holding member 60 that does not overlap with the support member 62, through the holding member 60, and the difference between the position of the region to be processed and the position of the processed mark 11c is detected (detection step). In the detection step, first, the imaging unit 46 is disposed at a position overlapping with the holding member 60 and not overlapping with the support member 62 by the same procedure as the determination step described above.

[0110] Also, the front surface 11a side of the work 11 is imaged by the imaging unit 46. Figure 6 The (B) is an image view showing the image 120 acquired by the imaging unit 46. In the image 120, the device 15 formed on the front surface 11a side of the work 11 and the linear processed mark 11c formed by the processing unit 32 (refer to Figure 1 ) are displayed.

[0111] Next, the position Al of the region to be processed and the position A2 of the processed mark 11c are detected. For example, the position of the center in the width direction of the division intended line 13, that is, the position at which the distance to the adjacent two devices 15 is equal, is detected as the position Al. Also, for example, the position of the center in the width direction of the processed mark 11c is detected as the position A2.

[0112] Also, the difference ΔA between the position Al of the region to be processed and the position A2 of the processed mark 11c is detected by the control section 50 (refer to Figure 1 ). This ΔA is stored in the storage section possessed by the control section 50 as correction information for correcting the position of the region to be processed in the correction step later. By this detection step, the amount of deviation of the position of the region to be processed from the position of the region actually processed is confirmed.

[0113] Next, the position of the work 11 to be processed by the processing unit 32 is corrected based on the difference ΔA between the position Al of the region to be processed and the position A2 of the processed mark 11c (position correction step). This position correction step is performed, for example, after a prescribed number of processed marks 11c are formed, or after the processing of one work 11 is completed and before the processing of another work 11 is started, and the like.

[0114] In the position correction step, the positions of the chuck table 26 and the processing unit 32 are offset by the amount of ΔA with reference to ΔA acquired as correction information in the detection step. Thereby, the difference between the position of the region to be processed and the position of the region actually processed is reduced. Also, when the processed mark 11c is formed along all of the division intended lines 13, the work 11 is divided into a plurality of device chips each having the device 15.

[0115] In addition, in the above embodiment, the case where the machining position is corrected in accordance with the position of the machining mark 11c generated by the cutting of the work 11 is described. However, the machining position can also be corrected in accordance with the position of the machining groove 11d (refer to FIG. 10(A)) formed on the back surface 11b side of the work 11 to a depth that does not reach the front surface 11a. Hereinafter, the method of correcting the machining position in accordance with the machining groove 11d will be described. Figure 7

[0116] First, the work 11 is held by the chuck table 26 (holding step). Figure 7 FIG. 10(A) is a partial cross-sectional side view showing the work 11 held by the chuck table 26. In the holding step, the work 11 is arranged on the chuck table 26 in such a manner that the front surface 11a side opposes the upper surface 60a of the holding member 60 and the back surface 11b side is exposed upward. Then, the above-described determination step is performed to determine the region of the work 11 to be machined.

[0117] Next, the machining groove 11d is formed on the work 11 along the region to be machined by the machining unit 32 (refer to FIG. 10(B)) (machining step). In the machining step, first, the length direction of the division predetermined line 13 of the work 11 is aligned with the X-axis direction. In addition, the positional relationship between the machining unit 32 and the chuck table 26 is adjusted in such a manner that the laser beam can be irradiated to the region to be machined. Figure 1

[0118] Then, the chuck table 26 is moved in the X-axis direction while the laser beam is irradiated from the machining unit 32 toward the back surface 11b side of the work 11. Thus, the laser beam is irradiated along the division predetermined line 13. In addition, the irradiation conditions of the laser beam are set so that the machining groove 11d having a depth smaller than the thickness of the work 11 can be formed on the back surface 11b side of the work 11.

[0119] Next, the machining groove 11d is imaged by the imaging unit 48 positioned on the upper side of the holding member 60, and the difference between the position of the region to be machined and the position of the machining groove 11d is detected (detection step). In the detection step, the machining groove 11d is imaged from the back surface 11b side of the work 11 by the imaging unit 48.

[0120] Figure 7 FIG. 10(B) is an image diagram showing the image 122 acquired by the imaging unit 46 and the image 124 acquired by the imaging unit 48. In addition, the image 122 is an image acquired by imaging the front surface 11a side of the work 11 by the imaging unit 46 in the above-described determination step. However, the front surface 11a side of the work 11 can also be imaged again by the imaging unit 46 in this detection step. ​​

[0121] The device 15 formed on the front surface 11a side of the work 11 is displayed in the image 122. In addition, the processing groove 11d formed on the back surface 11b side (metal layer 23 side) of the work 11 is displayed in the image 124.

[0122] Next, the position Bl of the region to be processed and the position B2 of the processing groove 11d are detected. For example, the position of the center in the width direction of the division predetermined line 13, which is the position at which the distance to the adjacent two devices 15 is equal, is detected as the position Bl based on the image 122. In addition, for example, the position of the center in the width direction of the processing groove 11d is detected as the position B2 based on the image 124.

[0123] Further, the difference ΔB between the position Bl of the region to be processed and the position B2 of the processing groove 11d is detected by the control section 50 (refer to Figure 1 ). This ΔB is stored in the storage section possessed by the control section 50 as correction information for correcting the position of the region to be processed in the following correction step.

[0124] Next, the position of the work 11 to be processed by the processing unit 32 is corrected based on the difference ΔB between the position Bl of the region to be processed and the position B2 of the processing groove 11d (position correction step). In the position correction step, the positions of the chuck table 26 and the processing unit 32 are offset by the amount of ΔB with reference to ΔB acquired as the correction information in the detection step. Thus, it is possible to reduce the deviation of the position of the region to be processed from the position actually processed.

[0125] In addition, the alignment of the work 11 before processing and the processing unit 32 can be performed using the photographing unit 46 and the photographing unit 48. Hereinafter, a specific example of the alignment of the work 11 and the processing unit 32 will be described.

[0126] First, the back surface 11b side (upper surface side) of the work 11 held by the chuck table 26 is photographed by the photographing unit 48 provided on the upper side of the holding member 60. Figure 8 (A) of FIG. 10 is a plan view showing the back surface 11b side of the work 11 photographed by the photographing unit 48. For example, the photographing unit 48 photographs a plurality of outer peripheral regions 130 (four positions in Figure 8 (A) of FIG. 10) of the work 11.

[0127] When the image of the outer peripheral region 130 of the work 11 is acquired by the photographing unit 48, the control section 50 (refer to Figure 1The coordinates of the outer periphery (end portion) of the workpiece 11 at three or more locations (for example, four locations) are detected. The detection of the outer periphery of the workpiece 11 is performed, for example, by performing prescribed image processing (edge detection, etc.) on the image acquired by the imaging unit 48.

[0128] Then, the control section 50 detects the center coordinates or the diameter of the workpiece 11 based on the coordinates of the outer periphery of the workpiece 11. Thereby, the shape of the workpiece 11 is recognized. In addition, whether the workpiece 11 is arranged at the desired position on the chuck table 26 is confirmed based on the center coordinates or the coordinates of the outer periphery of the workpiece 11.

[0129] On the other hand, the front surface 11a side (lower surface side) of the workpiece 11 held by the chuck table 26 is imaged by the imaging unit 46 provided on the lower side of the holding member 60. Figure 8 (B) of FIG. 13 is a bottom view showing the front surface 11a side of the workpiece 11 imaged by the imaging unit 46. In addition, targets (alignment marks) 132 serving as marks at the time of alignment of the workpiece 11 and the machining unit 32 (refer to Figure 1 ) are attached to the front surface 11a side of the workpiece 11. Figure 8 An example in which a pair of targets 132 is attached is shown in (B) of FIG. 13 as an example.

[0130] For example, the imaging unit 46 images the outer peripheral region 134 of the front surface 11a side of the workpiece 11 from the lower side of the holding member 60. The device 15 and the targets 132 formed on the front surface 11a side of the workpiece 11 are shown in the image acquired by the imaging unit 46. Then, the control section 50 (refer to Figure 1 ) adjusts the position and the angle of the chuck table 26 based on the positions of the device 15 and the targets 132 shown in the image, thereby performing the alignment of the workpiece 11 and the machining unit 32.

[0131] For example, the angle of the chuck table 26 is adjusted in such a manner that the pair of targets 132 attached to the workpiece 11 is arranged on a straight line parallel to the X-axis direction (refer to Figure 1 ). In addition, the position of the chuck table 26 is adjusted in such a manner that the position of the division intended line 13 of the workpiece 11 coincides with the irradiation position of the laser beam. The angle of the chuck table 26 is controlled by the angle control mechanism 28 (refer to Figure 1 , etc.), and the position of the chuck table 26 is controlled by the moving mechanism 8 (refer to Figure 1 ).

[0132] Furthermore, the dimensions of the device 15 and the width of the pre-defined dividing line 13 can be measured based on the image acquired by the imaging unit 46. In this case, the interval of the laser irradiation area can be set according to the actual dimensions of the device 15 and the width of the pre-defined dividing line 13.

[0133] Then, a laser beam is irradiated from the processing unit 32 toward the back side 11b of the workpiece 11 to perform the prescribed processing on the workpiece 11. Figure 8 (C) is a bottom view showing the front 11a side of the workpiece 11 being processed along the predetermined dividing line 13. For example, the workpiece 11 is divided along the predetermined dividing line 13 by irradiation with a laser beam.

[0134] In addition, when aligning the workpiece 11 and the processing unit 32, the imaging unit 46 can capture images of multiple areas of the workpiece 11. Figure 9 (A) is a bottom view showing the front 11a side of the workpiece 11 captured by the imaging unit 46 in the first outer peripheral region 136a. Figure 9 (B) is a bottom view showing the front 11a side of the workpiece 11 photographed by the photographing unit 46 in the second peripheral region 136b.

[0135] First, the first outer peripheral region 136a of the workpiece 11 is photographed by the imaging unit 46. Then, the angle of the workpiece 11 is adjusted based on the image of the first outer peripheral region 136a acquired by the imaging unit 46 (refer to...). Figure 9 (A)).

[0136] Here, when the alignment of the workpiece 11 and the processing unit 32 is performed based on an image of the area other than the first outer peripheral region 136a of the workpiece 11, the angle control mechanism 28 (see reference) is used to control the alignment. Figure 1 (etc.) rotate the chuck table 26 90° in the first direction (e.g., clockwise) (refer to) Figure 9 (B) The imaging unit 46 captures an image of the second outer peripheral region 136b of the workpiece 11. This acquires an image of the second outer peripheral region 136b of the workpiece 11. Furthermore, based on the image of the second outer peripheral region 136b, the position of the chuck table 26 is adjusted to align the workpiece 11 with the processing unit 32.

[0137] If the alignment of the workpiece 11 and the processing unit 32 is completed, the chuck table 26 is rotated 90° in a second direction opposite to the first direction (e.g., counterclockwise) to return the angle of the workpiece 11 to normal. Figure 9 The state shown in (A). Then, the workpiece 11 is irradiated with a laser beam, and the workpiece 11 is processed along the predetermined dividing line 13 (see reference). Figure 8 (C)).

[0138] In addition, in the above-described detection step, in a case where the machining mark 11c (refer to (A) of Figure 6 ) or the machining groove 11d (refer to (A) of Figure 7 ) is not formed in a range that can be imaged by the imaging unit 46 or the imaging unit 48, it is also possible to arrange the desired region of the workpiece 11 at the upper side of the imaging unit 46 by rotating the chuck table 26 as described above. Thereby, it is possible to detect the position of the machining mark 11c or the machining groove 11d at an arbitrary position of the workpiece 11.

[0139] As described above, the laser processing apparatus 2 of the present embodiment can image the workpiece 11 through the holding member 60 using the imaging unit 46 in a state where the imaging unit 46 is positioned at a region of the lower side of the holding member 60 and does not overlap with the support member 62 by moving the chuck table 26 by the moving mechanism 8. Thereby, it is possible to perform the alignment of the imaging unit 46 and the holding member 60 without additionally providing a moving mechanism for moving the imaging unit 46 in the horizontal direction, and it is possible to realize the downsizing of the laser processing apparatus 2.

[0140] In addition, in the laser processing apparatus 2, the angle control mechanism 28 is arranged at the lower side of the chuck table 26. Therefore, compared to a configuration in which the angle control mechanism 28 is provided at the side of the chuck table 26 or the like, the setting area of the laser processing apparatus 2 is reduced.

[0141] In addition, in the above-described Figure 1 , an example in which one set of the imaging unit 46 is provided at the rear of the moving mechanism 8 is shown, but two or more sets of the imaging unit 46 can be provided in the laser processing apparatus 2. For example, a moving mechanism 34, a support arm 44 provided from the moving mechanism 34 in the X-axis direction, and an imaging unit 46 fixed to the support arm 44 can be provided at the side of the moving mechanism 8. Thereby, it is possible to image two regions (for example, the first outer peripheral region 136a shown in (A) of Figure 9 and the second outer peripheral region 136b shown in (B) of Figure 9 ) of the workpiece 11 without rotating the chuck table 26.

[0142] In addition, in the above-described, the laser processing apparatus 2 that processes the workpiece 11 by irradiation of a laser beam is described, but there is no limitation to the kind of the processing apparatus of the present application. For example, the processing apparatus of the present application can be a cutting apparatus that cuts the workpiece 11.

[0143] The cutting apparatus has a chuck table that holds a workpiece 11, and a machining unit (cutting unit) that is provided with a ring-shaped cutting tool that cuts the workpiece 11 held by the chuck table. As the chuck table of the cutting apparatus, the chuck table 26 shown in (A) and (B) of Figure 3 Figure 3 the chuck table 80 shown in (A) and (B) of Figure 4 Figure 4 the chuck table 80 shown in (A) and (B) of

[0144] In addition, the configuration, method, and the like of the above-described embodiments can be appropriately changed and implemented within a range that does not depart from the object of the present application.​​

Claims

1. A processing apparatus, characterized in that, The processing device has the following features: A chuck table that uses a holding face to hold the workpiece. A processing unit that processes the workpiece held by the chuck table; A moving mechanism that moves the chuck table and the machining unit relative to each other in a direction parallel to the holding surface of the chuck table; An angle control mechanism, disposed on the moving mechanism and located below the chuck table, controls the angle of the chuck table; and The imaging unit takes pictures of the workpiece held on the chuck table. The chuck table includes: A holding component, made of a transparent body, holds the workpiece; and A support component, which is connected to the angle control mechanism, supports a portion of the retaining component. Without the need for a separate mechanism to move the imaging unit in a direction parallel to the holding surface of the chuck table, the imaging unit is positioned below the holding member and in an area that does not overlap with the support member by moving the chuck table through the moving mechanism, and the workpiece is photographed by the imaging unit through the holding member.

2. The processing apparatus according to claim 1, characterized in that, The angle control mechanism is a rotary mechanism that rotates the chuck table.

3. The processing apparatus according to claim 1 or 2, characterized in that, The chuck table also has an outer peripheral retaining member that retains the outer periphery of the retaining member. The outer peripheral retaining component is supported by the supporting component.

4. The processing apparatus according to claim 1 or 2, characterized in that, The processing device also has an upper imaging unit that takes pictures of the workpiece held by the chuck table from above the holding member.

5. The processing apparatus according to claim 4, characterized in that, The processing apparatus also includes an alignment component, on which a target for aligning the imaging unit with the upper imaging unit is attached. The target is photographed by the imaging unit located on the lower side of the holding member and the upper imaging unit located on the upper side of the holding member.

6. The processing apparatus according to claim 1 or 2, characterized in that, The processing apparatus also has a moving mechanism that moves the imaging unit along a direction perpendicular to the holding surface of the chuck table.

7. A method for processing a workpiece, comprising processing the workpiece using a processing apparatus, characterized in that, The processing device has the following features: A chuck table that holds the workpiece by using a holding face; A processing unit that processes the workpiece held by the chuck table; A moving mechanism that moves the chuck table and the machining unit relative to each other in a direction parallel to the holding surface of the chuck table; An angle control mechanism, disposed on the moving mechanism and located below the chuck table, controls the angle of the chuck table; and The imaging unit takes pictures of the workpiece held on the chuck table. The chuck table includes: A holding component, made of a transparent body, holds the workpiece; and A support component, which is connected to the angle control mechanism, supports a portion of the retaining component. The processing method for the workpiece includes the following steps: The adhesive step involves attaching the tape to the front side of the workpiece. The holding step involves holding the workpiece across the belt via the chuck table after the belt pasting step. The determination step involves, after the holding step, using the imaging unit located on the lower side of the holding member and not overlapping with the support member, to take a picture of the front side of the workpiece through the holding member, thereby determining the area of ​​the workpiece to be processed; The processing step involves cutting the workpiece along the area to be processed using the processing unit after the determination step. The inspection step, following the processing step, involves using an imaging unit positioned below the holding member and not overlapping with the support member to capture an image of the front side of the workpiece across the holding member, detecting the difference between the position of the area to be processed and the position of the processing mark formed by the processing step; and The position correction step corrects the position to be processed by the processing unit based on the difference between the position of the area to be processed and the position of the processing mark.

8. A method for processing a workpiece, comprising processing the workpiece using a processing apparatus, characterized in that, The processing device has the following features: A chuck table that holds the workpiece by using a holding face; A processing unit that processes the workpiece held by the chuck table; A moving mechanism that moves the chuck table and the machining unit relative to each other in a direction parallel to the holding surface of the chuck table; An angle control mechanism, disposed on the moving mechanism and located below the chuck table, controls the angle of the chuck table; and The first and second imaging units photograph the workpiece held by the chuck table. The chuck table includes: A holding component, made of a transparent body, holds the workpiece; and A support component, which is connected to the angle control mechanism, supports a portion of the retaining component. The processing method for the workpiece includes the following steps: The workpiece is held in a manner by the chuck table with the front side of the workpiece facing the upper surface of the holding member. After the holding step, the first imaging unit, located on the lower side of the holding member and not overlapping with the support member, takes a picture of the front side of the workpiece through the holding member to determine the area of ​​the workpiece to be processed. The processing step, after the determination step, involves forming a processing groove on the back side of the workpiece along the area to be processed by the processing unit; The detection step, following the processing step, involves using the second imaging unit positioned above the holding member to capture an image of the processing groove, and detecting the difference between the position of the area to be processed and the position of the processing groove; and The position correction step involves correcting the position of the processing unit based on the difference between the position of the area to be processed and the position of the processing slot.

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