Processing device and processing method of workpiece

Abstract

To provide a processing device and a processing method in which the cost and labor required to select a processing condition are reduced and an operation of selecting the processing condition is simplified.SOLUTION: A laser processing device 2 for processing a workpiece 11 in which a plurality of division lines are set and a plurality of structures are provided on the division lines includes: a processing unit 48 for performing laser processing on the workpiece 11; and a controller connected to a temporary placement mechanism 12, a transport unit 16, a movement unit 20, a holding unit 40, a clamp 42, a processing unit 48, an imaging unit 54, a cleaning unit 56, a display unit 62, and the like. The controller includes: a unit area storage part that stores a plurality of unit areas included in the workpiece 11 and having a common arrangement of structures; a processing condition storage part that stores the processing condition set for a unit area; and a processing control part that controls the processing unit such that the unit area is processed under the processing condition and a processing mark are formed in the unit area.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a processing apparatus used for processing a workpiece having a structure provided on a planned dividing line, and a method for processing a workpiece. [Background technology]

[0002] In the device chip manufacturing process, a wafer is used, on which devices are formed in multiple regions defined by planned division lines (streets) set in a grid pattern. This wafer is divided along the planned division lines to obtain device chips each including a device. Furthermore, a package substrate is formed by mounting multiple device chips on a predetermined substrate and covering and sealing the mounted device chips with a resin layer (mold resin). This package substrate is divided along the predetermined planned division lines to produce a packaged device each including multiple packaged device chips. Device chips and packaged devices are incorporated into various electronic devices, such as mobile phones and personal computers.

[0003] A cutting device is used to divide workpieces such as wafers and package substrates. The cutting device is equipped with a processing unit (cutting unit) that performs cutting on the workpiece, and an annular cutting blade is attached to the cutting unit. The workpiece is divided by rotating the cutting blade and cutting into the workpiece (see Patent Document 1).

[0004] In recent years, development has also been underway for processes for dividing workpieces by laser processing using a laser processing device. The laser processing device is equipped with a processing unit (laser irradiation unit) that irradiates the workpiece with a laser beam. For example, by irradiating the workpiece with a laser beam from the laser irradiation unit, a laser-processed groove or modified layer is formed in the workpiece along a planned dividing line. When an external force is then applied to the workpiece, the workpiece breaks starting from the laser-processed groove or modified layer, and the workpiece is divided along the planned dividing line (see Patent Documents 2 and 3). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-50214 [Patent Document 2] Japanese Patent Application Publication No. 10-305420 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-192370 Summary of the Invention [Problem to be solved by the invention]

[0006] When processing a workpiece using a processing device (such as a cutting device or a laser processing device) as described above, processing conditions are set according to the material of the workpiece, etc., so that the desired processing is performed on the workpiece. Furthermore, structures such as TEGs (Test Element Groups), electrodes, wiring, terminals, and circuits may be provided on the planned dividing lines of the workpiece. In this case, processing conditions are selected so that the workpiece can be divided along the planned dividing lines while appropriately removing the structures on the planned dividing lines.

[0007] However, the presence, placement, dimensions, material, etc. of structures may differ for each division line, and the machinability of the workpiece may differ depending on the presence or absence of structures. Therefore, processing the workpiece under the same processing conditions without considering the presence or absence of structures for each division line may result in processing defects and reduced processing efficiency. For example, if processing is performed up to a division line with structures under processing conditions suitable for processing a division line without structures, the structures may not be properly removed, which may result in processing defects. On the other hand, if processing is performed up to a division line without structures under processing conditions suitable for processing a division line with structures, excessive processing may be performed on the workpiece, resulting in large amounts of processing debris and processing defects, or a longer processing time may result in reduced processing efficiency.

[0008] Therefore, when selecting processing conditions, the workpiece is test-processed along multiple planned dividing lines, and the state of the workpiece after processing (presence and degree of processing defects, etc.) is checked. This makes it possible to set appropriate processing conditions for each planned dividing line that do not cause processing defects, even if the presence or absence of structures, etc., differs depending on the planned dividing line. However, using the above-mentioned method increases the amount of processing required to select processing conditions, and also widens the range of workpieces to be checked after processing. This increases the cost spent on selecting processing conditions, and the test processing takes time and effort.

[0009] The present invention has been made in consideration of such problems, and aims to provide a processing device and a method for processing a workpiece that can simplify the selection of processing conditions when processing a workpiece that has a structure provided on a planned division line. [Means for solving the problem]

[0010] According to one aspect of the present invention, there is provided a processing device for processing a workpiece on which a plurality of planned division lines are set and a plurality of structures are provided on the planned division lines, the processing device comprising: a processing unit for processing the workpiece; and a controller, the controller having a unit area memory section for storing a plurality of unit areas included in the workpiece and having a common arrangement of the structures; a processing condition memory section for storing processing conditions set for the unit areas; and a processing control section for controlling the processing unit so that the unit areas are processed under the processing conditions and processing marks are formed in the unit areas.

[0011] Preferably, the machining device further includes an imaging unit that images the workpiece, and the controller further includes an evaluation image storage unit that stores an evaluation image acquired by imaging the machining marks with the imaging unit. Also, preferably, the controller further includes a machining evaluation unit that evaluates the machining marks based on the evaluation image. Also, preferably, the machining condition storage unit stores a plurality of different machining conditions set for a plurality of unit areas, the machining control unit controls the machining unit so that the plurality of unit areas are machined under the different machining conditions, the machining evaluation unit evaluates the machining marks formed in each of the plurality of unit areas, and the controller further includes a machining condition selection unit that selects machining conditions for machining the workpiece with the machining unit based on the evaluation by the machining evaluation unit.

[0012] Preferably, the processing device further includes an imaging unit for imaging the workpiece, and the controller further includes a unit area setting section for setting the unit area to be stored in the unit area memory section, and the unit area setting section extracts multiple areas from the workpiece in which the structures have a common arrangement based on a detection image obtained by imaging the multiple structures provided on the workpiece with the imaging unit, and sets the areas as the unit areas.

[0013] According to another aspect of the present invention, there is provided a method for processing a workpiece on which a plurality of planned division lines are set and a plurality of structures are provided on the planned division lines, the method comprising: a unit area setting step for setting a plurality of unit areas included in the workpiece and having a common arrangement of the structures; a processing condition setting step for setting processing conditions for the unit areas; and a processing step for processing the unit areas under the processing conditions to form processing marks in the unit areas. [Effects of the Invention]

[0014] In a processing device and a method for processing a workpiece according to one aspect of the present invention, processing conditions are set for a unit area, which is a part of the workpiece, and processing the unit area under those processing conditions leaves a processing mark in the unit area. This makes it possible to significantly reduce the area of ​​the workpiece that is processed on a trial basis when selecting processing conditions. As a result, the cost and labor required for selecting processing conditions are reduced and the process of selecting processing conditions is simplified. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing a laser processing device. [Figure 2] FIG. [Figure 3] 10 is a flowchart showing a method for selecting processing conditions. [Figure 4] 10 is a cross-sectional view showing the laser processing device in a unit area setting step and a processing condition setting step. FIG. [Figure 5] FIG. 2 is a plan view showing a plurality of unit areas included in a workpiece. [Figure 6] FIG. 3 is a cross-sectional view showing the laser processing device in a processing step. [Figure 7] FIG. 7(A) is a plan view showing a unit area in the first half of processing, and FIG. 7(B) is a plan view showing a unit area in the second half of processing. [Figure 8] FIG. 2 is a cross-sectional view showing the laser processing apparatus when processing conditions are selected. [Figure 9] FIG. 2 is a plan view showing a unit area imaged by an imaging unit. [Figure 10] Figure 10(A) is an image diagram showing a first evaluation image obtained by imaging the first evaluation area, and Figure 10(B) is an image diagram showing a second evaluation image obtained by imaging the second evaluation area. [Figure 11] 10 is a graph showing processing mark information and evaluation results. DETAILED DESCRIPTION OF THE INVENTION

[0016] An embodiment according to one aspect of the present invention will be described below with reference to the accompanying drawings. First, a configuration example of a processing device according to this embodiment will be described. FIG. 1 is a perspective view showing a laser processing device 2 that performs laser processing on a workpiece 11. In FIG. 1, the X-axis direction (processing feed direction, first horizontal direction, left-right direction) and the Y-axis direction (indexing feed direction, second horizontal direction, front-back direction) are perpendicular to each other. Furthermore, the Z-axis direction (height direction, up-down direction, vertical direction) is perpendicular to the X-axis direction and the Y-axis direction.

[0017] The laser processing apparatus 2 includes a base 4 that supports the various components that make up the laser processing apparatus 2. A columnar protrusion 6 that protrudes upward from the base 4 is provided at a corner on the front end side of the base 4. A cassette setting table 8 is provided inside the protrusion 6. An elevation mechanism (not shown) that raises and lowers the cassette setting table 8 along the Z-axis direction is connected to the cassette setting table 8.

[0018] A cassette 10 is placed on the cassette setting table 8. The cassette 10 is a box-shaped container that can accommodate a plurality of workpieces 11, which are objects to be processed by the laser processing device 2. When processing the workpieces 11 with the laser processing device 2, the cassette 10 accommodating the plurality of workpieces 11 is set on the cassette setting table 8. The lifting mechanism adjusts the position (height position) of the cassette 10 in the Z-axis direction so that the workpieces 11 can be appropriately carried out from and carried into the cassette 10.

[0019] 2 is a plan view showing a workpiece 11. For example, the workpiece 11 is a disk-shaped wafer made of a semiconductor material such as single crystal silicon, and has a front surface (first surface) 11a and a back surface (second surface) 11b (see FIG. 4, etc.) that are generally parallel to each other. The workpiece 11 is partitioned into a plurality of rectangular regions by a plurality of planned division lines (streets) 13 that are arranged in a grid pattern so as to intersect with each other. Devices 15, such as ICs (Integrated Circuits), LSIs (Large Scale Integration), LEDs (Light Emitting Diodes), and MEMS (Micro Electro Mechanical Systems) devices, are formed on the front surface 11a side of each of the plurality of regions partitioned by the planned division lines 13.

[0020] The workpiece 11 has, on its surface 11a side, a substantially circular device region 17A in which a plurality of devices 15 are formed, and an annular peripheral surplus region 17B surrounding the device region 17A. The peripheral surplus region 17B corresponds to a strip-shaped region of a predetermined width (e.g., approximately 2 mm) that includes the outer periphery of the surface 11a. No devices 15 are formed in the peripheral surplus region 17B, or only devices (dummy devices) that will not be used in the product are formed therein. Note that in FIG. 2, the imaginary boundary between the device region 17A and the peripheral surplus region 17B is indicated by a dashed line.

[0021] Structures 19 are provided on some or all of the planned dividing lines 13. For example, the structures 19 correspond to TEGs for inspecting the devices 15, or electrodes, wiring, terminals, circuits, etc. formed on the front surface 11a of the workpiece 11. Furthermore, parts of thin films (conductive films, insulating films) constituting the devices 15 may remain as structures 19 on the planned dividing lines 13. FIG. 2 illustrates a case where a structure pattern consisting of four structures 19 arranged in a substantially cross shape is provided near the intersection of the planned dividing lines 13. However, the number, shape, arrangement, etc. of the structures 19 vary depending on the specifications of the workpiece 11.

[0022] By dividing the workpiece 11 along the planned dividing lines 13, a plurality of device chips each including a device 15 are obtained. When the workpiece 11 is divided, the structures 19 provided on the planned dividing lines 13 are processed and removed together with the workpiece 11.

[0023] However, there are no limitations on the type, material, shape, structure, size, etc. of workpiece 11. For example, workpiece 11 may be a substrate (wafer) made of a semiconductor other than silicon (GaAs, InP, GaN, SiC, etc.), sapphire, glass, ceramics, resin, metal, etc. Furthermore, there are no limitations on the type, number, shape, structure, size, arrangement, etc. of devices 15, and workpiece 11 does not necessarily have to have devices 15 formed thereon.

[0024] Furthermore, the workpiece 11 may be a package substrate such as a CSP (Chip Size Package) substrate or a QFN (Quad Flat Non-leaded package) substrate. For example, a package substrate is formed by mounting multiple device chips on a predetermined substrate and then covering and sealing the mounted device chips with a resin layer (mold resin). By dividing the package substrate along predetermined division lines, multiple package devices each including multiple packaged device chips are manufactured.

[0025] 1, when a workpiece 11 is processed by a laser processing device 2, the workpiece 11 is supported by an annular frame 21 for ease of handling (transporting, holding, etc.) the workpiece 11. The frame 21 is made of a metal such as stainless steel (SUS), and has a circular opening 21a at the center thereof that penetrates the frame 21 in the thickness direction. The diameter of the opening 21a is larger than the diameter of the workpiece 11.

[0026] A circular sheet 23 is fixed to the workpiece 11 and the frame 21. For example, a tape including a film-like base material and an adhesive layer (glue layer) provided on the base material is used as the sheet 23. However, the sheet 23 may be a sheet (thermocompression sheet) that does not include an adhesive layer (glue layer) and can be thermocompressed to the workpiece 11 and the frame 21.

[0027] With the workpiece 11 placed inside the opening 21a, the sheet 23 is fixed to the workpiece 11 and the frame 21 so as to cover the opening 21a. At this time, the center of the sheet 23 is attached to the back surface 11b of the workpiece 11, and the outer periphery of the sheet 23 is attached to the underside of the frame 21. As a result, the workpiece 11 is supported by the frame 21 via the sheet 23. Then, the workpiece 11 is accommodated in the cassette 10 while being supported by the frame 21.

[0028] A temporary placement mechanism 12 on which the workpiece 11 is temporarily placed is provided behind the protrusion 6. The temporary placement mechanism 12 includes a pair of guide rails 14A, 14B. The guide rails 14A, 14B move toward and away from each other along the X-axis direction while maintaining a state generally parallel to the Y-axis direction. Each of the guide rails 14A, 14B includes a support surface that supports the underside of the frame 21, and a side surface that is generally perpendicular to the support surface and contacts the outer periphery of the frame 21. The workpiece 11 and the frame 21 are aligned by sandwiching the frame 21 between the guide rails 14A, 14B.

[0029] A transport unit (transport mechanism) 16 that transports the workpiece 11 is provided above the temporary placement mechanism 12. The transport unit 16 includes a holding unit (holding mechanism) 18 that holds the workpiece 11, and a movement mechanism (not shown) that moves the holding unit 18 along the X-axis, Y-axis, and Z-axis directions.

[0030] For example, the holding unit 18 includes a plurality of suction pads that hold the frame 21 that supports the workpiece 11. The lower surfaces of the suction pads form a holding surface that suction-holds the upper surface of the frame 21. The holding surface of the suction pad is connected to a suction source (not shown) such as an ejector via a flow path (not shown), a valve (not shown), and the like formed inside the suction pad. In addition, a gripping portion (gripping mechanism) 18a that grips the frame 21 is provided at the end of the holding unit 18 on the protrusion 6 side (cassette 10 side).

[0031] The holding unit 18 moves along the Y-axis direction away from the cassette 10 while gripping the end of the frame 21 housed in the cassette 10 with the gripping portions 18a. As a result, the workpiece 11 together with the frame 21 is carried out of the cassette 10 and placed on the guide rails 14A, 14B. Furthermore, the holding unit 18 moves along the Y-axis direction toward the cassette 10 while gripping the frame 21 placed on the guide rails 14A, 14B with the gripping portions 18a. As a result, the workpiece 11 together with the frame 21 is carried into and housed in the cassette 10.

[0032] A moving unit (moving mechanism) 20 is provided on the side of the protrusion 6. The moving unit 20 includes a Y-axis moving unit (Y-axis moving mechanism) 22 provided on the base 4, and an X-axis moving unit (X-axis moving mechanism) 32 connected to the Y-axis moving unit 22.

[0033] The Y-axis movement unit 22 includes a pair of Y-axis guide rails 24 arranged along the Y-axis direction on the upper surface of the base 4. A flat Y-axis movement table 26 is mounted on the pair of Y-axis guide rails 24 so as to be slidable along the Y-axis guide rails 24.

[0034] A nut portion (not shown) is provided on the rear surface (lower surface) side of the Y-axis moving table 26. A Y-axis ball screw 28, which is disposed along the Y-axis direction between a pair of Y-axis guide rails 24, is threadedly engaged with this nut portion. A Y-axis pulse motor 30 is connected to an end of the Y-axis ball screw 28. When the Y-axis pulse motor 30 rotates the Y-axis ball screw 28, the Y-axis moving table 26 moves in the Y-axis direction along the Y-axis guide rails 24.

[0035] The X-axis movement unit 32 includes a pair of X-axis guide rails 34 arranged along the X-axis direction on the front (upper) surface side of the Y-axis movement table 26. A flat X-axis movement table 36 is mounted on the pair of X-axis guide rails 34 so as to be slidable along the X-axis guide rails 34.

[0036] A nut portion (not shown) is provided on the rear surface (lower surface) side of the X-axis moving table 36. An X-axis ball screw 38, which is disposed along the X-axis direction between a pair of X-axis guide rails 34, is threadedly engaged with this nut portion. An X-axis pulse motor (not shown) is also connected to the end of the X-axis ball screw 38. When the X-axis pulse motor rotates the X-axis ball screw 38, the X-axis moving table 36 moves in the X-axis direction along the X-axis guide rails 34.

[0037] A holding unit 40 that holds the workpiece 11 is connected to the moving unit 20. For example, the holding unit 40 is configured by a chuck table (holding table) and is installed on the surface (upper surface) of the X-axis moving table 36.

[0038] The upper surface of the holding unit 40 is a flat surface that is roughly parallel to the horizontal plane (XY plane) and constitutes a holding surface 40a that holds the workpiece 11. The holding surface 40a is connected to a suction source (not shown) such as an ejector via a flow path (not shown), a valve (not shown), and the like formed inside the holding unit 40. In addition, a plurality of clamps 42 that grip and fix the frame 21 that supports the workpiece 11 are provided around the periphery of the holding unit 40.

[0039] When the Y-axis moving table 26 is moved along the Y-axis direction, the holding unit 40 and the clamp 42 move along the Y-axis direction. When the X-axis moving table 36 is moved along the X-axis direction, the holding unit 40 and the clamp 42 move along the X-axis direction. Furthermore, the holding unit 40 is connected to a rotation drive source (not shown), such as a motor, that rotates the holding unit 40 and the clamp 42 around a rotation axis that is approximately parallel to the Z-axis direction.

[0040] The workpiece 11 is transported between the temporary placement mechanism 12 and the holding unit 40 by the transport unit 16. Specifically, the transport unit 16 transports the workpiece 11 and the frame 21 from the temporary placement mechanism 12 to the holding unit 40, or transports them from the holding unit 40 to the temporary placement mechanism 12, while holding the upper surface of the frame 21 by suction with a plurality of suction pads provided in the holding unit 18.

[0041] A rectangular parallelepiped support structure 44 is provided at the rear end of the base 4 (rear of the moving unit 20 and the holding unit 40). The support structure 44 is formed so as to protrude upward from the base 4, and the surface (front surface) of the support structure 44 is arranged along the XZ plane.

[0042] A columnar support member 46 that protrudes forward from the surface of the support structure 44 is connected to the support structure 44. The support member 46 supports components of a processing unit (laser irradiation unit) 48 mounted on the laser processing device 2.

[0043] The processing unit 48 performs laser processing on the workpiece 11 held by the holding unit 40 by irradiating the workpiece 11 with a laser beam. For example, the processing unit 48 includes a laser oscillator (not shown) such as a YAG laser, a YVO4 laser, or a YLF laser, and an optical system (not shown) that guides the laser beam emitted from the laser oscillator to the workpiece 11 held by the holding unit 40. The optical system includes various optical elements such as lenses, mirrors, and a condenser, and the condenser includes a condenser lens that condenses the laser beam.

[0044] The processing unit 48 also includes a laser processing head 50 attached to the tip of the support member 46. The laser processing head 50 houses optical elements such as a condenser. A laser beam 52 (see FIG. 6) emitted from the laser processing head 50 is irradiated onto the workpiece 11, thereby performing laser processing on the workpiece 11.

[0045] An imaging unit 54 is attached to the tip of the support member 46. The imaging unit 54 includes an image sensor such as a CCD (Charged-Coupled Devices) sensor or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor, and captures an image of the workpiece 11 held by the holding unit 40. There are no limitations on the type of imaging unit 54, and a visible light camera or an infrared camera, for example, may be used.

[0046] For example, the imaging unit 54 is installed adjacent to the laser processing head 50 in the X-axis direction. The alignment of the workpiece 11 with the laser processing head 50 is performed based on the image acquired by capturing an image of the workpiece 11 with the imaging unit 54. As will be described later, the image acquired by the imaging unit 54 is also used to set unit areas of the workpiece 11 (see FIG. 4) and to evaluate the workpiece 11 after processing (see FIG. 8).

[0047] The support member 46 may be connected to the support structure 44 via a Z-axis movement unit (not shown) that moves the support member 46 along the Z-axis direction. For example, a ball screw type movement mechanism is installed as the Z-axis movement unit on the front side of the support structure 44. In this case, the positions of the laser processing head 50 and the imaging unit 54 in the Z-axis direction can be adjusted by moving (raising and lowering) the support member 46 along the Z-axis direction with the Z-axis movement unit. This makes it possible to adjust the height position of the focal point of the laser beam 52 and to focus the imaging unit 54.

[0048] A cleaning unit 56 for cleaning the workpiece 11 is provided behind the temporary placement mechanism 12. For example, the cleaning unit 56 includes a spinner table 58 that holds and rotates the workpiece 11, and a fluid supply unit 60 that supplies a cleaning fluid to the workpiece 11.

[0049] The upper surface of spinner table 58 is a flat surface that is roughly parallel to the horizontal plane (XY plane) and constitutes a holding surface that holds workpiece 11. The holding surface of spinner table 58 is connected to a suction source (not shown) such as an ejector via a flow path (not shown), a valve (not shown), and the like formed inside spinner table 58.

[0050] A rotation drive source (not shown), such as a motor, is connected to the spinner table 58 to rotate the spinner table 58 around a rotation axis that is approximately parallel to the Z-axis direction. In addition, a plurality of clamps are provided around the periphery of the spinner table 58 to grip and fix the frame 21 that supports the workpiece 11.

[0051] The fluid supply unit 60 includes a nozzle that supplies a cleaning fluid for cleaning the workpiece 11. The cleaning fluid may be a liquid such as pure water or a mixed fluid obtained by mixing a liquid (such as pure water) with a gas (such as air). The nozzle is connected to a cleaning fluid supply source (not shown) that supplies the cleaning fluid to the nozzle, and a rotating arm (not shown) that rotates the nozzle along a horizontal plane (XY plane) above the spinner table 58.

[0052] The workpiece 11 is held by the spinner table 58, and while the spinner table 58 is rotating, a cleaning fluid is supplied to the workpiece 11 from the nozzle of the fluid supply unit 60, thereby cleaning the workpiece 11. This removes foreign matter such as machining chips adhering to the workpiece 11. The workpiece 11 is carried into and out of the fluid supply unit 60 by, for example, the transport unit 16.

[0053] The laser processing apparatus 2 also includes a display unit (display section, display device) 62 that displays various information related to the laser processing apparatus 2. For example, a touch panel display is used as the display unit 62. In this case, an operation screen for inputting information into the laser processing apparatus 2 is displayed on the display unit 62, and the operator can input information into the laser processing apparatus 2 by touching the display unit 62. In other words, the display unit 62 also functions as an input unit (input section, input device) for inputting information into the laser processing apparatus 2, and is used as a user interface. However, the input unit may be an electronic device such as a mouse, keyboard, transceiver, or the like that is provided separately and independently from the display unit 62.

[0054] Furthermore, the laser processing apparatus 2 includes a controller (control unit, control section, control device) 64 that controls the laser processing apparatus 2. The controller 64 is connected to each component (temporary placement mechanism 12, transport unit 16, moving unit 20, holding unit 40, clamp 42, processing unit 48, imaging unit 54, cleaning unit 56, display unit 62, etc.) that constitutes the laser processing apparatus 2. The controller 64 outputs control signals to each component of the laser processing apparatus 2, thereby controlling the operation of each component and operating the laser processing apparatus 2.

[0055] For example, the controller 64 is configured by a computer and includes a processing unit that executes processes such as calculations required for the operation of the laser processing device 2, and a storage unit that stores various information (data, programs, etc.) used for the operation of the laser processing device 2. The processing unit includes a processor such as a CPU (Central Processing Unit), and the storage unit includes memories such as a ROM (Read Only Memory) and RAM (Random Access Memory).

[0056] In this embodiment, the workpiece 11 is processed on a trial basis using the laser processing device 2, and then, based on the processing results, processing conditions for processing the workpiece 11 are selected. A specific example of a method for selecting processing conditions will be described below.

[0057] 3 is a flowchart showing a method for selecting processing conditions. In the method for selecting processing conditions according to this embodiment, a unit area setting step S1, a processing condition setting step S2, and a processing step S3 are performed to test-process the workpiece 11, an evaluation image acquisition step S4 and a processing evaluation step S5 are performed to evaluate the processing results of the workpiece 11, and a processing condition selection step S6 is performed to select processing conditions for processing the workpiece 11 based on the evaluation results. The process including the unit area setting step S1, the processing condition setting step S2, and the processing step S3 corresponds to the method for processing a workpiece according to this embodiment. Each step will be described in detail below.

[0058] Fig. 4 is a cross-sectional view showing the laser processing device 2 in the unit area setting step S1 and the processing condition setting step S2. Fig. 4 also shows a block diagram showing the functional configuration of the controller 64 (similar to Figs. 6 and 8). The controller 64 includes a processing unit 70 that executes processing required for processing the workpiece 11 and selecting the processing conditions, and a storage unit (memory) 72 that stores various information (data, programs, etc.) used for processing the workpiece 11 and selecting the processing conditions.

[0059] When setting the processing conditions, first, a unit area setting step S1 is performed to set a plurality of unit areas that are included in the workpiece 11 and have a common arrangement of structures 19. Then, a processing condition setting step S2 is performed to set the processing conditions for the unit areas.

[0060] 5 is a plan view showing a plurality of unit areas 25 included in the workpiece 11. The workpiece 11 can be divided into a plurality of unit areas 25 that have a common arrangement of structures 19 provided on the planned division lines 13. For example, a plurality of sets of structure patterns each consisting of four structures 19 arranged in a substantially cross shape are provided on the front surface 11a side of the workpiece 11. In this case, the smallest unit of the periodically arranged structure pattern can be considered as a unit area 25, and each of the plurality of unit areas 25 includes four structures 19.

[0061] The shape, size, and orientation of the structures 19 are generally the same among the multiple unit areas 25. However, even if the shape, size, or orientation of the structures 19 differs slightly among the multiple unit areas 25, the arrangement of the structures 19 can be considered to be common as long as the difference is within a predetermined tolerance range.

[0062] 5 shows an example in which 21 rectangular unit areas 25, each including four structures 19, are arranged in 5 rows and 5 columns along the length direction of the mutually intersecting planned division lines 13. However, the number, shape and arrangement of the unit areas 25 can be set appropriately depending on the arrangement of the planned division lines 13 and the structures 19.

[0063] If other structures are formed in areas outside the dividing lines 13 on the front surface 11a of the workpiece 11, the arrangement of the structures may differ among the multiple unit areas 25. Furthermore, the unit area 25 does not necessarily have to be the smallest unit of the structure pattern. That is, an area including multiple smallest units may also be considered as a unit area 25.

[0064] As shown in FIG. 4, in the unit area setting step S1, the workpiece 11 is imaged by the imaging unit 54 to obtain a detection image. Specifically, first, the workpiece 11 is held by the holding unit 40. The workpiece 11 is placed on the holding surface 40a so that the front surface 11a (the structure 19 side) faces upward and the back surface 11b (the sheet 23 side) faces the holding surface 40a. In addition, the frame 21 is fixed by a plurality of clamps 42. In this state, the suction force (negative pressure) of the suction source is applied to the holding surface 40a, so that the workpiece 11 is suction-held by the holding unit 40 via the sheet 23.

[0065] Next, the holding unit 40 is moved by the moving unit 20 (see FIG. 1 ), and the workpiece 11 is positioned so as to overlap with the imaging unit 54 in the Z-axis direction. Then, while the holding unit 40 is being moved, the imaging unit 54 captures images of the workpiece 11 multiple times. As a result, multiple detection images showing the structures 19 formed on the surface 11a side of the workpiece 11 are acquired. That is, each of the multiple detection images includes an image of the structures 19. The detection images acquired by the imaging unit 54 are input to the controller 64.

[0066] Next, a plurality of unit areas 25 (see FIG. 5) are set by the controller 64. Specifically, the processing unit 70 of the controller 64 includes a unit area setting unit 70a that sets the unit areas 25. Then, the unit area setting unit 70a sets the number, shape, dimensions, arrangement, etc. of the unit areas 25 based on the detection image input from the imaging unit 54.

[0067] For example, a structure pattern consisting of four structures 19 (see FIG. 5) arranged in a substantially cross shape is set as a landmark (key pattern). Then, the unit area setting unit 70a identifies the pitch of the structure pattern and sets unit areas 25 corresponding to the repeating units of the structure pattern.

[0068] Specifically, the workpiece 11 is imaged multiple times by the imaging unit 54, and multiple detection images showing the structure pattern (four structures 19) are obtained together with imaging position information. The imaging position information is information indicating the positional relationship between the workpiece 11 and the imaging unit 54 when the workpiece 11 is imaged, and for example, the XY coordinates of the holding unit 40 are used as the imaging position information. In addition, the memory unit 72 has reference images corresponding to the structure pattern stored in advance.

[0069] The unit area setting unit 70a performs pattern matching to compare each detection image input from the imaging unit 54 with a reference image read from the storage unit 72, and identifies the positions of each of the multiple structure patterns present on the workpiece 11 based on the pattern matching results and the imaging position information. The unit area setting unit 70a also calculates the pitch of the structure patterns and identifies areas corresponding to repeating units of the structure patterns. The unit area setting unit 70a then sets the identified areas as unit areas 25 and arranges the unit areas 25 as shown in FIG. 5.

[0070] In this way, the unit area setting unit 70a extracts a plurality of areas having a common arrangement of structures 19 from the workpiece 11 based on the detection image, and sets the areas as unit areas 25. Then, the unit areas 25 set by the unit area setting unit 70a are stored in a unit area storage unit 72a included in the storage unit 72. For example, the unit area storage unit 72a stores identification information (identification numbers, etc.), shapes, dimensions, arrangements, etc. of the plurality of unit areas 25.

[0071] The above-described unit area setting step S1 automatically sets a plurality of unit areas 25. However, the procedure for setting the plurality of unit areas 25 is not limited to the above. For example, the imaging unit 54 may acquire a single detection image showing the entire surface 11a side of the workpiece 11. In this case, the unit area setting section 70a sets a plurality of unit areas 25 based on the single detection image.

[0072] Alternatively, all or part of the unit area setting step S1 may be performed by an operator. For example, one or more detection images acquired by the imaging unit 54 are displayed on the display unit 62 (see FIG. 1) or transmitted to the outside. The operator then visually checks the detection images and sets the number, shape, dimensions, arrangement, etc. of the multiple unit areas 25 at his or her own discretion. In this case, information on the multiple unit areas 25 set by the operator is input to the unit area storage unit 72a, which then stores the multiple unit areas 25 set by the operator in the unit area storage unit 72a.

[0073] Next, a processing condition setting step S2 is performed to set processing conditions for the unit area 25. Below, an example will be described in which different processing conditions are set for each of the multiple unit areas 25 (see FIG. 5) set in the unit area setting step S1.

[0074] In the processing condition setting step S2, processing conditions for processing the unit areas 25 of the workpiece 11 with the laser beam 52 (see FIG. 6) irradiated from the processing unit 48 are set for each of the plurality of unit areas 25. Specifically, the processing unit 70 of the controller 64 includes a processing condition setting unit 70b that sets processing conditions for the unit areas 25. The processing condition setting unit 70b then reads out information on the plurality of unit areas 25 stored in the unit area storage unit 72a, and sets processing conditions for each of the plurality of unit areas 25.

[0075] Specifically, the processing condition setting unit 70b sets values ​​of processing condition items when processing the unit area 25 with the laser beam 52 along the planned division lines 13. Examples of the processing condition items include the focusing position of the laser beam 52, wavelength, average output, repetition frequency, processing feed speed, the number of planned division lines 13, etc.

[0076] The processing condition setting unit 70b sets the processing conditions according to predetermined conditions set in advance so that the values ​​of at least one or more processing condition items differ among the plurality of unit areas 25. For example, when 21 unit areas 25 are set as shown in Fig. 5, the processing condition setting unit 70b can assign the average output of the laser beam (minimum 1.0 W, maximum 3.0 W) to the plurality of unit areas 25 so that each output differs by 0.1 W.

[0077] However, the method for setting the items of processing conditions that differ between unit areas 25 and their values ​​can be freely set according to the type, material, etc. of the workpiece 11 and the structure 19. For example, processing conditions may be set for multiple unit areas 25 so that the processing feed rate or the repetition frequency of the laser beam 52 differs by a predetermined value between multiple unit areas 25.

[0078] The processing conditions set by the processing condition setting unit 70b are stored in a processing condition storage unit 72b included in the storage unit 72. In particular, when different processing conditions are set for multiple unit areas 25, the processing conditions are stored in the processing condition storage unit 72b in a state linked to the identification information of the unit areas 25.

[0079] In the above-described machining condition setting step S2, machining conditions are automatically set for the plurality of unit areas 25. However, the machining condition setting step S2 may also be performed by an operator. For example, the operator selects, at his / her own discretion, the machining conditions for each of the plurality of unit areas 25 set in the unit area setting step S1 and inputs them into the controller 64. In this case, the machining conditions set by the operator are input into the machining condition setting unit 70b, and the machining condition setting unit 70b stores the machining conditions set by the operator in the machining condition memory unit 72b.

[0080] Next, a processing step S3 is performed in which the unit area 25 is processed under the processing conditions set in the processing condition setting step S2 to form processing marks in the unit area 25. The processing of the unit area 25 is controlled by the controller 64.

[0081] 6 is a cross-sectional view showing the laser processing device 2 in processing step S3. The processing unit 70 of the controller 64 includes a processing control unit 70c that controls processing of the unit area 25. The processing control unit 70c controls the components (processing unit 48, etc.) of the laser processing device 2 so that the unit area 25 is processed under the processing conditions set in processing condition setting step S2 and processing marks are formed in the unit area 25.

[0082] Specifically, first, the machining conditions for each unit area 25 stored in the machining condition storage unit 72b are read out. Then, the machining control unit 70c outputs control signals to the moving unit 20 (see FIG. 1), the machining unit 48, etc. so that the unit area 25 is machined in accordance with the read-out machining conditions. As a result, the machining conditions are switched for each unit area 25, and the laser beam 52 is irradiated onto each of the multiple unit areas 25 along the planned division lines 13. As a result, machining marks 11c are formed on the workpiece 11 along the planned division lines 13.

[0083] For example, the irradiation conditions of the laser beam 52 are set so that ablation processing is performed on the unit area 25 of the workpiece 11. Specifically, the wavelength of the laser beam 52 is set so that at least a portion of the laser beam 52 is absorbed by the workpiece 11 and the structure 19. In other words, the laser beam 52 is a laser beam that is absorbable by the workpiece 11 and the structure 19. In addition, other irradiation conditions of the laser beam 52 are also set appropriately so that ablation processing is appropriately performed on the workpiece 11 and the structure 19. For example, when the workpiece 11 is a single crystal silicon wafer, the irradiation conditions of the laser beam 52 can be set as follows: Wavelength: 355nm Average output power: 1.0W~3.0W Repetition frequency: 200kHz Processing feed rate: 500mm / s

[0084] 6 illustrates a case where the processing mark 11c is a kerf extending from the front surface 11a to the back surface 11b of the workpiece 11, but the form of the processing mark 11c is not limited to this. For example, the processing mark 11c may be a groove (laser-processed groove) formed on the front surface 11a side of the workpiece 11 and having a depth less than the thickness of the workpiece 11.

[0085] 7(A) and 7(B) show how processing marks 11c are formed in a unit area 25 by irradiation with the laser beam 52. Here, as an example, a case will be described in which one unit area 25 includes parts of four planned division lines 13.

[0086] 7(A) is a plan view showing the unit area 25 in the first half of processing. When processing the unit area 25, first, the holding unit 40 (see FIG. 6) is rotated to adjust the angle of the workpiece 11 so that the length direction of the first planned dividing line 13 is along the X-axis direction. In addition, the positional relationship between the holding unit 40 and the laser processing head 50 (see FIG. 6) is adjusted so that the position where the laser beam 52 (see FIG. 6) is irradiated is positioned on an extension of the first planned dividing line 13.

[0087] Then, the laser processing head 50 irradiates the workpiece 11 with the laser beam 52 so that the unit area 25 is irradiated with the laser beam 52 under the processing conditions set in the processing condition setting step S2, and the holding unit 40 and the laser beam 52 move relatively along the X-axis direction (processing feed). As a result, the unit area 25 is processed along the first planned division line 13, and linear processing marks 11c are formed along the first planned division line 13.

[0088] Next, the holding unit 40 and the laser processing head 50 move relatively along the Y-axis direction by the distance of the planned dividing line 13 (indexing feed). Then, in the same procedure, the laser beam 52 is irradiated onto the unit area 25. As a result, the unit area 25 is processed along the second planned dividing line 13 that is parallel to the first planned dividing line 13, and linear processing marks 11c are formed along the second planned dividing line 13.

[0089] 7(B) is a plan view showing the unit area 25 in the latter half of processing. After processing marks 11c are formed along the first and second planned division lines 13, the holding unit 40 is rotated by 90°. As a result, the third and fourth planned division lines 13 that intersect with the first and second planned division lines 13 are arranged along the X-axis direction. Then, the laser beam 52 is irradiated onto the unit area 25 according to the procedure described above. As a result, linear processing marks 11c are formed sequentially along the third and fourth planned division lines 13.

[0090] When one unit area 25 includes a plurality of planned division lines 13, the unit area 25 may be processed under different processing conditions for each planned division line 13. In this case, in the above-mentioned processing condition setting step S2 (see FIG. 4), the processing condition setting unit 70b sets different processing conditions for each planned division line 13. Then, in processing step S3 (see FIG. 6), the processing control unit 70c controls the components of the laser processing device 2 so that the unit area 25 is processed under different processing conditions for each planned division line 13.

[0091] For example, the unit area 25 shown in FIGS. 7A and 7B includes a portion of two division lines 13 (division lines 13A) on which structures 19 are provided, and a portion of two division lines 13 (division lines 13B) on which no structures 19 are provided. In this case, the processing conditions (processing conditions A) used to process the unit area 25 along the division lines 13A may be different from the processing conditions (processing conditions B) used to process the unit area 25 along the division lines 13B. For example, the average power of the laser beam 52 under processing condition A is set to a value higher by a predetermined amount (e.g., 0.5 W) than the average power of the laser beam 52 under processing condition B so that the structures 19 present on the division lines 13A are appropriately removed. Furthermore, the processing feed rate under processing condition A may be set to a value lower than the processing feed rate under processing condition B.

[0092] Furthermore, a plurality of processing conditions can be set for one planned division line 13. For example, if one planned division line 13 includes an area where structures 19 are provided and an area where no structures 19 are provided, different processing conditions can be set for both areas. In this case, in the above-mentioned processing condition setting step S2 (see FIG. 4), the processing condition setting unit 70b sets a plurality of processing conditions for one planned division line 13. Then, in processing step S3 (see FIG. 6), the processing control unit 70c controls the components of the laser processing device 2 so that the unit area 25 is processed along one planned division line 13 under different processing conditions.

[0093] As described above, the plurality of unit areas 25 included in the workpiece 11 are periodically arranged adjacent to one another (see FIG. 5). When processing the plurality of unit areas 25, the laser beam 52 is irradiated along the intended dividing line 13 while switching processing conditions at the boundary between adjacent unit areas 25. This allows the plurality of unit areas 25 to be processed continuously under different processing conditions.

[0094] However, if it is difficult to continuously process a plurality of unit areas 25 by switching processing conditions at the boundaries of adjacent unit areas 25, the workpiece 11 may be divided into a plurality of unit areas 25, and then each of the unit areas 25 may be processed. Specifically, before the processing step S3, a dividing step is performed in which the workpiece 11 is divided along the boundaries of the unit areas 25. To divide the workpiece 11, a cutting device that cuts the workpiece 11 with an annular cutting blade or a laser processing device 2 may be used. As a result, the workpiece 11 is divided into a plurality of chips corresponding to the unit areas 25. Thereafter, the above-mentioned processing step S3 is performed sequentially on the plurality of chips corresponding to the unit areas 25. As a result, the plurality of unit areas 25 can be individually processed.

[0095] After the processing step S3 is completed, the processing conditions used to process the unit area 25 can be evaluated for suitability by observing the processing marks 11c formed in the unit area 25. For example, if the processing marks 11c are formed in a straight line as shown in Figure 7(B), it is determined that the processing conditions were appropriate. On the other hand, if there are many chips (chipping) formed on the edge of the processing marks 11c, if the processing marks 11c are meandering, if the structures 19 on the planned division lines 13 have not been properly removed, or the like, it is determined that the processing conditions were inappropriate.

[0096] As described above, in the machining step S3, the unit areas 25 are machined under the machining conditions set for each unit area 25, and machining marks 11c are formed in the unit areas 25. As described above, the workpiece 11 is composed of a periodic arrangement of the unit areas 25 (see FIG. 5). Therefore, if the machining marks 11c formed in one unit area 25 are normal, it can be predicted that no machining defects will occur in the workpiece 11 even if the entire workpiece 11 is machined under the machining conditions used when machining that unit area 25. In other words, it is possible to select the machining conditions for the entire workpiece 11 by trial machining a unit area 25 corresponding to a portion of the workpiece 11.

[0097] As described above, in the processing device and workpiece processing method according to this embodiment, processing conditions are set for a unit area 25, which is a part of the workpiece 11, and the unit area 25 is processed under those processing conditions to form processing marks 11c in the unit area 25. This makes it possible to significantly reduce the area of ​​the workpiece 11 that is processed on a trial basis when selecting processing conditions. As a result, the cost and labor spent on selecting processing conditions are reduced, and the process of selecting processing conditions is simplified.

[0098] In the present embodiment, an example has been described in which the laser processing device 2 performs ablation processing on the workpiece 11. However, there are no limitations on the type of laser processing performed on the workpiece 11. For example, the laser processing device 2 can irradiate the workpiece 11 with a laser beam to form a modified layer (degraded layer) in the workpiece 11 that functions as a division starting point (a trigger for division).

[0099] Specifically, a laser beam that is transparent to the workpiece 11 is irradiated from the processing unit 48 (see FIG. 1 ) onto the workpiece 11 along the planned dividing lines 13. When this laser beam is focused inside the workpiece 11, the inside of the workpiece 11 is modified (altered) by multiphoton absorption. As a result, a modified layer is formed inside the workpiece 11 along the planned dividing lines 13. The area of ​​the workpiece 11 where the modified layer is formed becomes more fragile than other areas of the workpiece 11. Therefore, when an external force is applied to the workpiece 11 on which the modified layer has been formed along the planned dividing lines 13, the modified layer functions as a dividing starting point, and the workpiece 11 is divided along the planned dividing lines 13.

[0100] When the modified layer is formed in the unit area 25 in the above-mentioned processing step S3, cracks generated in the modified layer propagate inside the unit area 25 and reach the front or back surface of the unit area 25. Then, the cracks that appear on the front or back surface of the unit area 25 are observed and evaluated as processing marks 11c.

[0101] In addition, in this embodiment, a case has been described in which different machining conditions are set for each of the multiple unit areas 25. However, for example, when conducting a test to confirm that the already set machining conditions are appropriate, one unit area 25 may be machined under predetermined machining conditions and the machining marks 11c formed in the unit area 25 may be observed. This allows the appropriateness of one type of machining condition to be easily confirmed using one unit area 25.

[0102] After the workpiece 11 is processed by the workpiece processing method according to this embodiment (unit area setting step S1 to processing step S3), processing conditions suitable for processing the workpiece 11 may be selected based on the processing results. Hereinafter, a case where the processing results are evaluated and the processing conditions are selected using the laser processing device 2 will be described.

[0103] 8 is a cross-sectional view showing the laser processing apparatus 2 when selecting processing conditions. For example, the laser processing apparatus 2 selects new processing conditions for appropriately processing the workpiece 11 by sequentially executing an evaluation image acquisition step S4, a processing evaluation step S5, and a processing condition selection step S6.

[0104] Specifically, first, an evaluation image acquisition step S4 is performed in which an evaluation image is acquired by capturing an image of the processing marks 11c formed in the unit area 25 of the workpiece 11 with the imaging unit 54. In the evaluation image acquisition step S4, the front surface 11a side of the workpiece 11 is imaged by the imaging unit 54 in the same procedure as in the unit area setting step S1 (see FIG. 4) described above. As a result, the processing marks 11c formed on the front surface 11a side of the workpiece 11 are captured, and an evaluation image showing the processing marks 11c is acquired.

[0105] 9 is a plan view showing a unit area 25 imaged by the imaging unit 54. For example, two areas including the intersection of two processing marks 11c formed in the above-mentioned processing step S3 are set as evaluation areas (image capture areas) 80A, 80B used for evaluating the processing marks 11c. The evaluation areas 80A, 80B may be automatically designated by the controller 64 or may be designated by an operator. Then, in the evaluation image acquisition step S4, the evaluation areas 80A, 80B are imaged by the imaging unit 54, thereby acquiring images of the evaluation areas 80A, 80B.

[0106] 10(A) is an image diagram showing an evaluation image 82A acquired by imaging the evaluation area 80A, and FIG. 10(B) is an image diagram showing an evaluation image 82B acquired by imaging the evaluation area 80B. The evaluation image 82A displays two processing marks 11c formed to intersect with each other and four structures 19 with portions removed. On the other hand, the evaluation image 82B displays two processing marks 11c formed to intersect with each other, but does not display the structures 19.

[0107] Then, the above-described acquisition of evaluation images is performed for the other unit areas 25, and evaluation images 82A and 82B are acquired for all the unit areas 25. Then, the evaluation images 82A and 82B acquired by the imaging unit 54 are output to the controller 64.

[0108] The position, range, number, etc. of the evaluation areas imaged by the imaging unit 54 can be changed as appropriate depending on the state of the processing marks 11c, etc. For example, the entire unit area 25 or one area including the evaluation areas 80A and 80B may be set as the evaluation area. Furthermore, if there is an area where processing defects are particularly likely to occur, that area may be set as the evaluation area.

[0109] 8, the processing unit 70 of the controller 64 includes an evaluation image acquisition unit 70d that acquires evaluation images. Evaluation images 82A and 82B acquired by the imaging unit 54 are input to the evaluation image acquisition unit 70d, and the evaluation image acquisition unit 70d acquires the evaluation images 82A and 82B. The evaluation images 82A and 82B acquired by the evaluation image acquisition unit 70d are stored in an evaluation image storage unit 72c included in the storage unit 72.

[0110] The evaluation image used for evaluating the processing marks 11c is acquired by the evaluation image acquisition step S4. Although the above description has been given of the case where the workpiece 11 is imaged by the imaging unit 54, there are no limitations on the method for acquiring the evaluation image. For example, the workpiece 11 may be imaged by another imaging unit inside or outside the laser processing apparatus 2. In this case, the evaluation image showing the processing marks 11c is input to the evaluation image acquisition section 70d from the imaging unit that imaged the workpiece 11.

[0111] Next, a processing evaluation step S5 is performed to evaluate the processing marks 11c based on the evaluation images 82A and 82B. In the processing evaluation step S5, the state of the processing marks 11c is evaluated based on the information on the processing marks 11c shown in the evaluation images 82A and 82B.

[0112] FIG. 10(A) shows an example of information on the processing marks 11c. In FIG. 10(A), W p is the position P of one edge of the processing mark 11c in the width direction. p1 From the other edge position P p2 It indicates the distance to the p corresponds to the width of the processing mark 11c. pc indicates the center position of the processed mark 11c in the width direction. p and central position P pc This can be used to evaluate whether the position and dimensions of the processing mark 11c are appropriate.

[0113] Furthermore, when the processing mark 11c is formed, chipping (chipping) 11d may be formed at the edge of the processing mark 11c. c is the position P of the edge of the processing mark 11c p1 or P p2 Tip position P of chipping 11d ct It indicates the distance to the c corresponds to the chipping length. c is the position P of one end of the chipping 11d in the width direction. c1 From the other end position P c2 It indicates the distance to the c corresponds to the width of the chipping 11d. The number of chippings 11d and their length L c , width W c , area, etc. can be used to evaluate the processing quality.

[0114] The evaluation of the processing marks 11c is performed automatically by, for example, the controller 64. Specifically, as shown in Fig. 8, the processing unit 70 of the controller 64 includes a processing evaluation unit 70e that evaluates the processing marks 11c based on the evaluation images 82A and 82B. The processing evaluation unit 70e performs predetermined processing (image processing, etc.) on the evaluation images 82A and 82B to extract information used for evaluating the processing marks 11c from the evaluation images 82A and 82B.

[0115] For example, the processing evaluation unit 70e extracts the contours of the processing marks 11c and chippings 11d shown in the evaluation images 82A and 82B by performing image processing such as edge detection on the evaluation images 82A and 82B. Then, the processing evaluation unit 70e calculates the width W of the processing marks 11c based on the positions of the contours of the processing marks 11c and chippings 11d. p , central position P pc , number of chippings 11d, length L c , width W c The processing evaluation unit 70e also calculates the length L of the plurality of chippings 11d included in one unit area 25. c and width W cAlternatively, the machining evaluation unit 70e may calculate the maximum value of the center position P between the planned division line 13 and the machining marks 11c. pc The off-center, which is the amount of positional deviation between the processed mark 11c and the center line, may be calculated. These pieces of information are used as information (processing mark information) for evaluating the processed mark 11c.

[0116] Next, the processing evaluation unit 70e determines the state of the processing marks 11c based on the processing mark information. The processing evaluation unit 70e may determine the state of the processing marks 11c based on specific processing mark information extracted from the evaluation images 82A, 82B, or may determine the state of the processing marks 11c by comprehensively considering all of the processing mark information extracted from the evaluation images 82A, 82B.

[0117] 11 is a graph showing processing mark information and evaluation results. For example, the processing evaluation unit 70e uses the maximum value of the length of the chippings 11d (maximum chipping length), the total area of ​​the chippings 11d, off-center, and the number of chippings 11d extracted from the evaluation images 82A and 82B to evaluate the processing marks 11c. In addition, the storage unit 72 pre-stores a calculation formula for calculating a score representing the state of the processing marks 11c based on this processing mark information.

[0118] The processing evaluation unit 70e then calculates a score by applying the values ​​of the processing mark information extracted from the evaluation images 82A, 82B to the calculation formula read out from the storage unit 72. For example, the score represents the state of the processing marks 11c as a numerical value, with 100 representing the best state of the processing marks 11c and 0 representing the worst state of the processing marks 11c. Note that the specific content of the calculation formula can be freely set by the evaluator depending on the priority of each item included in the processing mark information.

[0119] Furthermore, the processing evaluation unit 70e may determine whether the state of the processing marks 11c is good or bad based on the processing mark information. For example, the storage unit 72 pre-stores reference values ​​(threshold values) that define the allowable ranges for each item included in the processing mark information (maximum length of chippings 11d, total area of ​​chippings 11d, off-center, number of chippings 11d). The processing evaluation unit 70e then compares the value of each item included in the processing mark information with the reference value to determine whether the state of the processing marks 11c is good or bad.

[0120] Specifically, the processing evaluation unit 70e determines whether the value of each item included in the processing mark information is within an allowable range defined by a respective reference value (for example, whether it is equal to or less than an upper limit value). If the values ​​of all items included in the processing mark information are within the allowable range (normal values), the processing evaluation unit 70e evaluates that the condition of the processing mark 11c is good. On the other hand, if the value of any item included in the processing mark information is outside the allowable range (abnormal value), the processing evaluation unit 70e evaluates that the condition of the processing mark 11c is bad.

[0121] The evaluation of the processing marks 11c as described above is performed for each of the multiple unit regions 25. However, there are no limitations on the method of evaluating the processing marks 11c. For example, the processing evaluation unit 70e may determine whether the processing marks 11c are good or bad by comparing a score calculated based on the processing mark information with a preset reference value (threshold value) of the score.

[0122] 8, the processing mark information extracted by the processing evaluation unit 70e and the results of the evaluation by the processing evaluation unit 70e (score, pass / fail, etc.) are stored in an evaluation result storage unit 72d included in the storage unit 72. As a result, the evaluation elements and evaluation results of the processing marks 11c for each of the multiple unit regions 25 are accumulated in the evaluation result storage unit 72d.

[0123] However, the evaluation of the processing marks 11c in the processing evaluation step S5 may be performed by an operator. For example, evaluation images 82A and 82B acquired by the imaging unit 54 are displayed on the display unit 62 (see FIG. 1) or transmitted to an external device. The operator then visually checks the evaluation images 82A and 82B and evaluates the state of the processing marks 11c at his or her own discretion. In this case, the results of the operator's evaluation (score, pass / fail, etc.) are input to the controller 64 and stored in the evaluation result storage unit 72d.

[0124] Furthermore, instead of referring to the evaluation images 82A and 82B, the operator may evaluate the state of the processing marks 11c by observing the unit area 25 of the workpiece 11 directly or using a microscope, etc. In this case, the above-mentioned evaluation image acquisition step S4 can be omitted.

[0125] Next, a processing condition selection step S6 is performed to select processing conditions for processing the workpiece 11. In the processing condition selection step S6, processing conditions are selected based on the evaluation in the processing evaluation step S5 so that the workpiece 11 is properly processed.

[0126] The selection of the machining conditions is automatically performed by, for example, the controller 64. Specifically, as shown in Fig. 8, the processing unit 70 of the controller 64 includes a machining condition selection unit 70f that selects the machining conditions. The machining condition selection unit 70f selects the machining conditions for machining the workpiece 11 with the machining unit 48 (see Fig. 1, etc.) based on the evaluation of the machining marks 11c by the machining evaluation unit 70e.

[0127] For example, the machining condition selection unit 70f refers to the machining mark information and the evaluation results (see FIG. 11) stored in the evaluation result storage unit 72d, and identifies the unit area 25 with the highest score. Then, the machining condition selection unit 70f selects the machining conditions used when the identified unit area 25 was machined in the above-mentioned machining step S3 (see FIG. 6) as the machining conditions for machining the workpiece 11.

[0128] However, the method for selecting the processing conditions is not limited to the above. For example, the processing condition selection unit 70f may extract processing conditions for a plurality of unit areas 25 that have been evaluated as having good processing marks 11c from the evaluation result shown in Fig. 11, and select processing conditions for processing the workpiece 11 by a predetermined method from the extracted plurality of processing conditions.

[0129] Specifically, the machining condition selection unit 70f may select, from the extracted plurality of machining conditions, the machining condition with the lowest average output of the laser beam 52 as the machining condition for machining the workpiece 11. In this case, the average output of the laser beam 52 can be kept low within a range in which the workpiece 11 is properly machined, thereby reducing the burden on the machining unit 48 (see FIG. 1, etc.) and suppressing the generation of machining chips (debris). Furthermore, the machining condition selection unit 70f may select, from the extracted plurality of machining conditions, the machining condition with the highest machining feed rate as the machining condition for machining the workpiece 11. In this case, the machining feed rate can be set high within a range in which the workpiece 11 is properly machined, improving machining efficiency.

[0130] The processing conditions selected by the processing condition selection unit 70f are stored in a processing condition storage unit 72e included in the storage unit 72. Then, when the workpiece 11 is subsequently processed by the laser processing device 2, a control signal is output from the processing control unit 70c to each component of the laser processing device 2 so that the workpiece 11 is processed under the processing conditions stored in the processing condition storage unit 72e.

[0131] The number of machining conditions selected in machining condition selection step S6 may be one or two or more. Specifically, when it is assumed that one workpiece 11 will be machined under one type of machining condition, one type of machining condition suitable for machining the workpiece 11 is selected. On the other hand, when it is assumed that one workpiece 11 will be machined under different machining conditions for each of the planned division lines 13A and 13B (see FIGS. 7(A) and 7(B)), for example, machining conditions suitable for machining the workpiece 11 along the planned division line 13A and machining conditions suitable for machining the workpiece 11 along the planned division line 13B may be selected individually.

[0132] Furthermore, the selection of the machining conditions in machining condition selection step S6 may be performed by an operator. For example, the machining mark information and evaluation results (see FIG. 11) stored in the evaluation result storage unit 72d are displayed on the display unit 62 (see FIG. 1) or transmitted to the outside. Then, the operator selects, at his own discretion, the machining conditions that are most suitable for machining the workpiece 11 based on the machining mark information and the evaluation results. In this case, the machining conditions selected by the operator are stored in the machining condition storage unit 72e.

[0133] As described above, by carrying out the steps from evaluation image acquisition step S4 to processing condition selection step S6, processing conditions for processing the workpiece 11 are selected based on the information acquired based on the workpiece processing method according to this embodiment (unit area setting step S1 to processing step S3). Thereafter, a new workpiece 11 is carried out from the cassette 10 (see FIG. 1) and processed under the selected processing conditions.

[0134] When the same type of workpiece 11 is processed by the laser processing device 2, after the processing conditions are selected using the above procedure, multiple workpieces 11 can be processed consecutively under those processing conditions. For example, a cassette 10 (see FIG. 1) set in the laser processing device 2 contains multiple workpieces 11 with the same arrangement of structures 19. In this case, the above-mentioned unit area setting step S1 to processing condition selection step S6 are performed using the first workpiece 11 to select the processing conditions, and then the second and subsequent workpieces 11 can be processed in order under the selected processing conditions.

[0135] As described above, the machining device and machining condition selection method according to this embodiment can machine one workpiece 11 under a plurality of machining conditions for each unit area 25, and select from these machining conditions specific machining conditions suitable for machining the workpiece 11. This makes it possible to perform test machining under a number of machining conditions using one workpiece 11, greatly simplifying the process of selecting machining conditions.

[0136] In the above embodiment, an example has been described in which the workpiece 11 is processed by the laser processing device 2. However, the processing device according to the present invention is not limited to the laser processing device 2. For example, the configuration and method according to the present invention can also be applied to a cutting device that cuts the workpiece 11 with an annular cutting blade.

[0137] The cutting device includes a holding unit that holds the workpiece 11, and a processing unit (cutting unit) that performs cutting on the workpiece 11. The cutting unit has a built-in spindle, and an annular cutting blade is attached to the tip of the spindle. The workpiece 11 is cut by holding the workpiece 11 with the holding unit and rotating the cutting blade to cut into the workpiece 11.

[0138] By applying the present invention to a cutting device, it is possible to efficiently select appropriate processing conditions when cutting the workpiece 11 with a cutting blade. Examples of processing conditions that are set when processing the workpiece 11 with a cutting device include the type of cutting blade (diameter, thickness, material, etc.), the rotation speed of the spindle (the rotation speed of the cutting blade), the processing feed rate, the number of planned division lines 13, etc.

[0139] In addition, the structures, methods, etc. according to the above-described embodiments can be modified as appropriate without departing from the scope of the object of the present invention. [Explanation of symbols]

[0140] 11 Workpiece 11a Surface (first side) 11b Back side (2nd side) 11c Machining marks 11d Chipping 13, 13A, 13B Planned division line (street) 15 devices 17A Device Area 17B Surplus outer area 19 Structures 21 frames 21a opening 23 seats 25 unit areas 2. Laser processing equipment 4 Foundation 6 Convex part 8 Cassette installation stand 10 cassettes 12 Temporary placement mechanism 14A, 14B guide rails 16 Transport unit (transport mechanism) 18 Holding unit (holding mechanism) 18a Gripping part (gripping mechanism) 20 Mobile unit (mobile mechanism) 22 Y-axis movement unit (Y-axis movement mechanism) 24 Y-axis guide rail 26 Y-axis moving table 28 Y-axis ball screw 30 Y-axis pulse motor 32 X-axis movement unit (X-axis movement mechanism) 34 X-axis guide rail 36 X-axis moving table 38 X-axis ball screw 40 Holding Unit 40a Holding surface 42 Clamp 44 Support structure 46 Support member 48 Processing unit (laser irradiation unit) 50 laser processing head 52 Laser Beam 54 Imaging unit 56 Cleaning Unit 58 Spinner Table 60 Fluid supply unit 62 Display unit (display unit, display device) 64 Controller (control unit, control section, control device) 70 Processing section 70a Unit area setting section 70b Machining condition setting section 70c Machining control unit 70d Evaluation image acquisition unit 70e Processing Evaluation Department 70f Machining condition selection section 72 Memory 72a Unit area memory section 72b Machining condition memory section 72c Evaluation image storage unit 72d Evaluation result storage unit 72e Machining condition memory section 80A, 80B Evaluation area (imaging area) 82A, 82B Evaluation images

Claims

1. A processing apparatus for processing a workpiece on which a plurality of planned dividing lines are set and a plurality of structures are provided on the planned dividing lines, a processing unit that processes the workpiece; a controller; The controller a unit area storage unit that stores a plurality of unit areas that are included in the workpiece and have a common arrangement of the structures; a processing condition storage unit that stores processing conditions set for the unit area; a machining control unit that controls the machining unit so that the unit area is machined under the machining conditions and machining marks are formed in the unit area.

2. Further provided is an imaging unit for imaging the workpiece, 2. The processing device according to claim 1, wherein the controller further comprises an evaluation image storage section that stores an evaluation image acquired by imaging the processing mark with the imaging unit.

3. The processing device according to claim 2 , wherein the controller further comprises a processing evaluation unit that evaluates the processing marks based on the evaluation image.

4. the processing condition storage unit stores a plurality of different processing conditions respectively set for a plurality of the unit areas; the machining control unit controls the machining unit so that the plurality of unit areas are machined under different machining conditions, the processing evaluation unit evaluates the processing marks formed in each of the plurality of unit areas; 4. The machining apparatus according to claim 3, wherein the controller further comprises a machining condition selection section that selects machining conditions for machining the workpiece with the machining unit based on the evaluation by the machining evaluation section.

5. Further provided is an imaging unit for imaging the workpiece, the controller further includes a unit area setting unit that sets the unit area to be stored in the unit area storage unit; The processing device according to claim 1, wherein the unit area setting unit extracts a plurality of areas from the workpiece in which the structures have a common arrangement based on a detection image obtained by capturing an image of the plurality of structures provided on the workpiece with the imaging unit, and sets the areas as the unit areas.

6. A method for processing a workpiece, in which a plurality of planned dividing lines are set and a plurality of structures are provided on the planned dividing lines, comprising: a unit area setting step of setting a plurality of unit areas that are included in the workpiece and have a common arrangement of the structures; a processing condition setting step for setting processing conditions for the unit area; a processing step of processing the unit area under the processing conditions to form a processing mark in the unit area.

Images