JP2013091087A - Laser beam machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam machining device capable of suppressing reduction in working efficiency by decreasing a downtime in machining as much as possible.SOLUTION: The laser beam machining device 1 includes a chuck table 10 for holding a workpiece W, a laser beam irradiation means 20 for irradiating laser beam to a surface of the workpiece W, and a powder dust discharge means 60 arranged at an end part of a condenser 22 for sucking/discharging powder dust generated near a machining point. The device 1 also includes an output measurement means 50 for measuring output of laser beam, a powder dust processing device for catching powder dust contained in exhaust gas and discharging only the exhaust gas, an opening/closing valve arranged between the powder dust discharge means 60 and the powder dust processing device, and a control means 90. When measuring the output of the laser beam, the control means 90 closes the opening/closing valve. When performing laser machining of the workpiece W, the opening/closing valve is opened.

Description

  The present invention relates to a laser processing apparatus that performs ablation processing by irradiating a workpiece held on a chuck table with a laser beam.

  As a method of dividing a wafer, such as a semiconductor wafer or an optical device wafer, along a street, a laser processing groove is formed by irradiating a laser beam along the street formed on the wafer. A method of breaking along the line has been put into practical use. However, when the laser beam is irradiated along the street of the wafer, the thermal energy concentrates on the irradiated area, debris is generated, and this debris adheres to a bonding pad or the like connected to the circuit to reduce the quality of the chip. New problems arise. In order to solve such problems, there has been proposed a laser processing method in which a processing surface of a wafer is coated with a protective coating such as polyvinyl alcohol and the wafer is irradiated with a laser beam through the protective coating (for example, a patent) Reference 1).

JP 2004-188475 A

  As described above, when a laser beam is irradiated onto a wafer that is a workpiece, debris is generated, and dust containing the debris is scattered, so the laser processing apparatus sucks and discharges the scattered dust. It has. However, when dust accumulates in the suction duct of the dust discharging means and high temperature debris scattered on the accumulated dust adheres, there is a problem that heat is generated. In particular, when a laser processing method is applied in which the wafer processing surface is coated with a protective coating such as polyvinyl alcohol and the wafer is irradiated with a laser beam through the protective coating, the accumulated dust is more likely to generate heat. There's a problem.

  On the other hand, the laser processing apparatus needs to periodically determine whether or not the output of the laser beam used for processing exceeds a predetermined output, and is provided with a so-called thermal output measuring means for measuring the output of the laser beam. Yes. When measuring the output of the laser beam with this thermal output measuring means, the blower for suction of the dust discharging means is stopped in order to accurately measure the output of the laser beam.

  The blower for suction of the dust discharge means takes time until it can be stably suctioned from the start. For this reason, when the laser processing apparatus performs laser processing on the workpiece after measuring the output of the laser beam by the thermal output measuring means, it starts driving the blower after the measurement is completed, and the blower is stabilized. After the dust can be sucked, the workpiece is laser processed. The time required for the blower to stably suck dust becomes a downtime of laser processing, and the laser processing apparatus has a problem that work efficiency is lowered.

  This invention is made | formed in view of the said fact, The main technical subject is to provide the laser processing apparatus which can suppress the down time at the time of a process as much as possible, and can suppress the fall of work efficiency.

  In order to solve the above main technical problems, according to the present invention, a chuck table for holding a workpiece and a laser processing groove formed by ablation by irradiating the surface of the workpiece held on the chuck table with a laser beam. Laser beam irradiating means provided with a concentrator for forming, and processing by the laser beam disposed on the downstream end of the concentrator in the direction of laser beam irradiation and irradiated to the workpiece by the concentrator A dust discharging means for sucking and discharging dust generated near the point, an output measuring means for measuring the output of the laser beam irradiated from the condenser, and the dust A dust treatment device connected to the discharge means via a discharge pipe and capturing dust contained in the exhaust and discharging only the exhaust to the duct; the dust discharge means and the dust treatment; An on-off valve disposed between the devices, and a control means for controlling the on-off valve, and when measuring the output of the laser beam with the output measuring means before processing the workpiece, The control means closes the opening / closing valve, the dust processing device and the dust discharging means are disconnected from each other, and when the workpiece is processed by the laser beam irradiation means, the opening / closing valve is opened to open the dust processing device. There is provided a laser processing apparatus characterized in that a suction force acts near the processing point and the dust generated by the processing is discharged.

  The laser processing apparatus of the present invention is disposed between the dust processing apparatus and the dust discharging means by operating the dust processing apparatus from beginning to end even when measuring the output of the laser beam by the thermal output measuring means. By closing the open / close valve, the output measuring means can accurately measure the output of the laser beam.

  In addition, when the dust treatment device is in operation all the time, after closing the open / close valve and measuring the output of the laser beam by the thermal output measuring means, opening the open / close valve and starting laser processing, immediately the dust by the dust discharge means Starts to be discharged. For this reason, even when measuring the laser beam output by the thermal output measuring means, the dust processing device can be driven stably, and the dust can be discharged immediately after the laser beam output measurement, and laser processing can be performed. Can do. Therefore, the downtime at the time of a process can be reduced as much as possible, and the fall of work efficiency can be suppressed.

FIG. 1 is a diagram illustrating a schematic configuration example of a laser processing apparatus according to an embodiment. FIG. 2 is a diagram showing the dust discharging means and the dust processing device. FIG. 3 is a diagram illustrating a flow of an output measurement operation of the laser processing apparatus according to the embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the structures described below can be combined as appropriate. Various omissions, substitutions, or changes in the configuration can be made without departing from the scope of the present invention.

  FIG. 1 is a diagram illustrating a schematic configuration example of a laser processing apparatus according to an embodiment. FIG. 2 is a diagram showing the dust discharging means and the dust processing device.

  The laser processing apparatus 1 according to the present embodiment performs ablation processing on the workpiece W by relatively moving the laser beam irradiation means 20 and the chuck table 10 holding the workpiece W, and the workpiece W A laser processing groove (not shown) is formed. As shown in FIG. 1, the laser processing apparatus 1 includes a chuck table 10, a laser beam irradiation means 20, a Y-axis movement means 30, an X-axis movement means 40, an output measurement means 50, a dust discharge means 60, A dust processing device 70 (shown in FIG. 2), an on-off valve 80 (shown in FIG. 2), and a control means 90 are configured. The laser processing apparatus 1 is provided with a column 3 erected upward from the outer edge of the apparatus main body 2.

  The chuck table 10 holds the workpiece W on a horizontal surface. In this embodiment, the chuck table 10 holds the workpiece W by sucking it from the back surface of the workpiece W. The portion constituting the surface of the chuck table 10 has a disk shape made of porous ceramic or the like, and is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown). A pair of clamp portions 11 are provided around the chuck table 10. The clamp unit 11 is driven by an air actuator and clamps the frame F around the workpiece W.

  The Y-axis moving unit 30 moves the workpiece W held with respect to the laser beam irradiation unit 20 relative to the Y-axis direction. The Y-axis moving unit 30 includes a Y-axis ball screw 31, a Y-axis pulse motor 32, and a pair of Y-axis guide rails 33. The Y-axis ball screw 31 is disposed on the apparatus body 2 in the Y-axis direction, is screwed with a nut (not shown) provided at the lower portion of the first slide block 34, and has a Y-axis pulse motor 32 at one end. Are connected. The pair of Y-axis guide rails 33 are disposed on the apparatus main body 2 in parallel with the Y-axis ball screw 31, and the first slide block 34 is slidably mounted thereon. The Y-axis moving means 30 rotates and drives the Y-axis ball screw 31 by the rotational force generated by the Y-axis pulse motor 32 so that the first slide block 34 and the second slide block 44 described later, that is, the chuck table 10 are paired. The apparatus body 2 is moved in the Y-axis direction while being guided by the Y-axis guide rail 33.

  The X-axis moving unit 40 moves the workpiece W held with respect to the laser beam irradiation unit 20 relative to the X-axis direction. The X-axis moving means includes an X-axis ball screw 41, an X-axis pulse motor 42, and a pair of X-axis guide rails 43. The X-axis ball screw 41 is disposed on the first slide block 34 in the X-axis direction, is screwed with a nut (not shown) provided at the lower portion of the second slide block 44, and has an X-axis pulse at one end. A motor 42 is connected. The pair of X-axis guide rails 43 are disposed on the first slide block 34 in parallel with the X-axis ball screw 41, and the second slide block 44 is slidably mounted thereon. The X-axis moving means 40 rotates and drives the X-axis ball screw 41 by the rotational force generated by the X-axis pulse motor 42, thereby guiding the second slide block 44, that is, the chuck table 10 by the pair of X-axis guide rails. Move in the X-axis direction with respect to the apparatus body 2.

  Here, the chuck table 10 is mounted on the second slide block 44 via a cylindrical support member 45 provided with a chuck table rotating means for rotating the chuck table 10. The chuck table 10 can be moved in the Y-axis direction and the X-axis direction by the Y-axis moving unit 30 and the X-axis moving unit 40.

  The laser beam irradiation means 20 irradiates the surface of the workpiece W held on the chuck table 10 with a laser beam to form a laser processing groove by ablation processing. The laser beam irradiation means 20 irradiates the laser beam oscillation means 21 supported by the column 3 erected from the apparatus main body 2 and the laser beam oscillated by the laser beam oscillation means 21 onto the surface of the workpiece W held on the chuck table 10. Then, a condenser 22 for forming a laser processing groove on the surface of the workpiece W by ablation processing is provided.

  The laser beam oscillating means 21 of the laser beam irradiating means 20 can be appropriately selected according to the type of workpiece W, the processing form, etc. For example, a YAG laser oscillator or a YVO laser oscillator can be used. The condenser 22 condenses the laser beam oscillated by the laser beam oscillation means 21, guides it to the surface of the workpiece W, performs ablation processing for sublimating a part of the workpiece W, and forms the laser processing groove. Form. The condenser 22 includes a total reflection mirror (not shown) for changing the traveling direction of the laser beam oscillated by the laser beam oscillating means 21 and a condenser lens (not shown) for correcting the chromatic aberration for condensing the laser beam. It only has to be.

  The output measuring unit 50 is a so-called thermal output measuring unit that measures the output of the laser beam emitted from the condenser 22 of the laser beam irradiating unit 20. In the present embodiment, the output measuring unit 50 receives the laser beam from the laser beam irradiating unit 20 and is heated according to the output of the laser beam to indicate the temperature difference before and after heating by the laser beam or the temperature after heating by the laser beam. Information is output to the control means 90. The output measuring means 50 is provided on the upper end surface of the small diameter cylindrical support member 46 erected from above the second slide block 44 and is adjacent to the chuck table 10.

  The dust discharge means 60 is disposed at the downstream end of the laser beam irradiation means 20 in the laser beam irradiation direction of the condenser 22. As shown in FIG. 2, the dust discharge means 60 is sucked by the blower of the dust processing device 70, so that the workpiece W is irradiated by the laser beam applied to the workpiece W from the condenser 22 of the laser beam irradiation means 20. Dust generated near the processing point (point where the laser beam is irradiated) is sucked and discharged. As shown in FIG. 2, the dust discharging means 60 includes an annular bottom portion 62 having a fitting hole 61 that fits outside the case 23 of the light collector 22, and a cylindrical mounting portion erected from the bottom portion 62. 63 and a cylindrical suction part 64 that hangs down from the outer peripheral edge of the annular bottom part 62. The inside of the suction part 64 is opened so as not to block the laser beam irradiated from the condenser 22. One end of a discharge pipe 65 is connected to the mounting portion 63 of the dust discharge means 60.

  The dust treatment device 70 is connected to the dust discharge means 60 via the discharge pipe 65, captures dust contained in the exhaust, and discharges only the exhaust, that is, the atmosphere, to the duct 71. The dust processing apparatus 70 includes a processing tank 72 whose interior is partitioned into an introduction chamber and a separation chamber (not shown), a blower (not shown) that discharges the atmosphere in the separation chamber of the processing tank 72 to the duct 71, and the like. The other end of the discharge pipe 65 is connected to the upper part of the introduction chamber of the treatment tank 72, and water is sprayed into the introduction chamber. Further, in the processing tank 72, a communication port (not shown) is provided which communicates the lower end portion of the introduction chamber and the lower end portion of the separation chamber and is located below the level of the water sprayed into the introduction chamber. One end of the duct 71 is connected to the upper end of the separation chamber, and the blower discharges the atmosphere in the separation chamber to the duct 71. The blower sucks the atmosphere in the vicinity of the opening 64 a of the dust discharge means 60 through the introduction chamber and the discharge pipe 65 by discharging the atmosphere in the separation chamber to the duct 71. In the dust treatment apparatus 70, the blower sucks the atmosphere in the vicinity of the opening 64a of the dust discharge means 60 while water is sprayed into the introduction chamber, and separates and captures the dust from the exhaust gas containing the dust sucked by the dust discharge means 60. Thus, only the exhaust is discharged into the duct 71.

  The on-off valve 80 is disposed at the center of the discharge pipe 65, that is, between the dust discharge means 60 and the dust processing device 70. The open / close valve 80 can freely open and close the flow path in the discharge pipe 65. In the present invention, the closing of the flow path in the discharge pipe 65 by the opening / closing valve 80 means that the flow path is completely closed and the flow measurement means does not affect the measurement result of the output measuring means practically. Including narrowing the path (closing most of the flow path with a very small gap in part).

  The control means 90 controls each component of the laser processing apparatus 1. That is, the control means 90 controls the open / close valve 80. The control means 90 causes the laser processing apparatus 1 to perform ablation processing on the workpiece W. Moreover, the control means 90 controls the quality determination of the output of the laser beam irradiated by the laser beam irradiation means 20 as the output measurement operation of the laser processing apparatus 1. The control means 90 is mainly composed of an arithmetic processing unit constituted by, for example, a CPU or the like and a microprocessor (not shown) provided with a ROM, a RAM, etc. It is connected to operating means used when registering content information and the like.

  Next, the processing operation of the laser processing apparatus 1 according to this embodiment will be described. Here, the workpiece W to be processed by the laser processing apparatus 1 is a wafer such as a semiconductor wafer or an optical device wafer whose base material is silicon, sapphire, gallium or the like in the present embodiment. The workpiece W has a back surface opposite to the device W3 side surface on which a plurality of devices W3 are formed attached to the dicing tape T, and the dicing tape T attached to the workpiece W is attached to the frame F. By being worn, it is fixed to the frame F. Further, a plurality of first streets W1 parallel to each other and a plurality of second streets W2 parallel to each other are formed on the surface of the workpiece W so as to be orthogonal to each other. A device W3 is formed in an area partitioned by two streets W2.

  First, when the operator registers the machining content information and receives an instruction to start the machining operation, the machining operation is started. In the processing operation, the blower of the dust treatment device 70 starts to be driven, and the atmosphere near the opening 64a of the suction part 64 of the dust discharge means 60 is sucked through the discharge pipe 65 and the like. Then, since the sucked atmosphere is discharged to the duct 71 of the dust treatment device 70, the vicinity of the opening 64a of the suction portion 64 becomes a negative pressure. The workpiece W is placed on the chuck table 10 by unloading / unloading means (not shown). The workpiece W held on the chuck table is sucked onto the chuck table 10, and the frame F is fixed by the clamp portion 11 and held on the chuck table 10.

  The workpiece W held on the chuck table 10 is moved below the imaging means (not shown) supported by the column 3 by the Y-axis moving means 30 and the X-axis moving means 40 and is imaged by the imaging means. In addition to a normal imaging device (CCD) that captures an image with visible light, the imaging unit includes an infrared irradiation unit that irradiates the workpiece W with infrared rays, an optical system that captures infrared rays emitted by the infrared irradiation unit, and the optical system. Infrared imaging means including an infrared imaging device such as an infrared CCD that outputs an electrical signal corresponding to infrared rays captured by the system is included, and the captured image signal is output to the control means 90.

  The control means 90 performs alignment between the streets W1 and W2 of the workpiece W held on the chuck table 10 and the condenser 22 of the laser beam irradiation means 20 that irradiates laser beams along the streets W1 and W2. Image processing such as pattern matching is executed, and alignment of the laser beam irradiation means 20 is performed.

  Then, the chuck table 10 holding the workpiece W is moved to the laser beam irradiation region below the condenser 22 of the laser beam irradiation unit 20 supported by the column 3 by the Y-axis moving unit 30 and the X-axis moving unit 40. Then, one end of the predetermined streets W1 and W2 is positioned immediately below the condenser 22. At this time, since the time has elapsed since the blower of the dust treatment device 70 was driven, the atmosphere near the opening 64a of the dust discharge means 60 can be stably sucked. The chuck table 10 holding the workpiece W while irradiating the laser beam from the condenser 22 of the laser beam irradiation means 20 in a state where the blower of the dust processing device 70 is driven is predetermined along predetermined streets W1 and W2. Move at a machining feed rate of.

  On the predetermined streets W1 and W2 irradiated with the laser beam, a part of the workpiece W is sublimated to form a laser processing groove. When the other ends of the predetermined streets W1 and W2 reach directly below the condenser 22, the irradiation of the laser beam from the laser beam irradiation means 20 is stopped and the movement of the chuck table 10, that is, the workpiece W is stopped. As described above, the laser processing apparatus 1 sequentially irradiates the streets W1 and W2 with laser beams to form laser processing grooves on the streets W1 and W2, and thus, on all the streets W1 and W2 of the workpiece W. Form a laser processed groove.

  When a part of the workpiece W is sublimated by this laser beam irradiation, dust generated near the processing point of the workpiece W by the laser beam is sucked from the opening 64a of the dust discharge means 60 and It flows into the processing tank 72. Further, water is sprayed in the introduction chamber of the treatment tank 72. As a result, a part of the dust in the exhaust in the introduction chamber of the treatment tank 72 drops and falls to the water in the treatment tank 72 while the remaining dust flows into the separation chamber from the introduction chamber together with the exhaust. Water that has been lifted up in the separation chamber adheres. The dust adhered to the water in the exhaust gas in the separation chamber falls into the water as it is with water droplets, and also falls into the water through a water level stabilizer (not shown) provided in the separation chamber.

  In this way, when the dust with water droplets falls into the water, only the exhaust from which the dust has been removed is discharged from the treatment tank 72 to the duct 71. Thus, in the laser processing apparatus 1, when the workpiece W is processed by the laser beam irradiation means 20, the opening / closing valve 80 is opened, the dust processing apparatus 70 and the dust discharge means 60 are communicated by the discharge pipe 65, and the blower As a result of the suction, a suction force acts near the processing point, and dust generated by the processing is discharged.

  If laser processing grooves are formed in all the streets W1 and W2 of the workpiece W, the chuck table 10 holding the workpiece W is first moved by the Y-axis moving means 30 and the X-axis moving means 40. The workpiece W is returned to the position where the workpiece W is sucked and held, and the sucking and holding of the workpiece W is released here. Then, after the workpiece W after laser processing is taken out from the chuck table 10 by the loading / unloading means, the workpiece W before laser processing is placed on the chuck table 10 by the loading / unloading means. Even when the workpiece W after laser processing and the workpiece W before laser processing are exchanged, the blower of the dust processing device 70 continues to be driven.

  Next, the output measurement operation of the laser processing apparatus 1 according to this embodiment will be described. FIG. 3 is a diagram illustrating a flow of an output measurement operation of the laser processing apparatus according to the embodiment. The output measuring operation is an operation for determining whether or not the output of the laser beam emitted from the laser beam application means 20 exceeds a predetermined output.

  First, the control unit 90 determines whether the output of the laser beam irradiated from the laser beam irradiation unit 20 exceeds a predetermined output for each workpiece W immediately before the workpiece W is processed, for example. It is determined whether or not it is necessary to determine (step ST1). Whether or not it is necessary to judge the output of the laser beam emitted from the laser beam irradiation means 20 depends on the number of workpieces W subjected to laser processing by the laser beam irradiation means 20, the diameter of the workpiece W, the laser beam irradiation means. It is preferable to make a determination based on at least one such as 20 drive times.

  Next, when the control unit 90 determines that it is necessary to determine the output of the laser beam irradiated from the laser beam irradiation unit 20 (Yes in step ST1), the laser beam is being processed by the laser beam irradiated from the laser beam irradiation unit 20. It is determined whether or not (step ST2). If it is determined that it is not necessary to determine the output of the laser beam irradiated from the laser beam irradiation means 20 (No in step ST1), it is determined that the output determination of the laser beam irradiated from the laser beam irradiation means 20 needs to be performed. Until step ST1 is repeated.

  Next, when it is determined that the laser beam is not being processed by the laser beam irradiated from the laser beam irradiation unit 20 (No in step ST2), the control unit 90 performs output determination of the laser beam irradiated from the laser beam irradiation unit 20 (step ST3). ). Here, the laser beam irradiation means 20 is not currently laser processing, for example, when the laser processing apparatus 1 is started, when the workpiece W after laser processing is replaced with the workpiece W before laser processing, or laser processing. When laser processing of the workpiece W by the apparatus 1 is not performed, the laser beam output determination is executed. In addition, at the time of starting of the laser processing apparatus 1, the control means 90 drives the air blower of the dust processing apparatus 70 rapidly.

  In determining the output of the laser beam, first, the control unit 90 drives the output measuring unit 50 to the condenser of the laser beam irradiating unit 20 by the Y-axis moving unit 30 and the X-axis moving unit 40 while driving the blower of the dust processing device 70. Move to just below 22.

  Next, the control means 90 closes the open / close valve 80 to block communication between the dust treatment device 70 and the dust discharge means 60 through the discharge pipe 65. Then, the atmosphere in the vicinity of the opening 64 a of the dust discharging means 60 is not sucked (or hardly sucked) by the blower of the dust processing device 70, and no suction force is generated in the atmosphere in the vicinity of the opening 64 a of the dust discharging means 60. Then, the atmosphere around the output measuring means 50 is not sucked into the opening 64a of the dust discharging means 60 (almost not sucked), and the atmosphere around the output measuring means 50 does not flow (almost no flow). Thus, the control unit 90 closes the opening / closing valve 80 and regulates the flow of the atmosphere around the output measurement unit 50.

  The control unit 90 irradiates the laser beam from the laser beam irradiation unit 20 toward the output measurement unit 50. Then, the output measuring unit 50 is heated by the laser beam irradiated from the laser beam irradiation unit 20. Based on the information from the output measuring means 50, the control means 90 determines whether or not the output of the laser beam from the laser beam irradiation means 20 exceeds a predetermined output.

  Here, for example, the temperature before and after heating or the temperature after heating detected by the output measuring unit 50 after a predetermined time has elapsed from the start of irradiation of the laser beam from the laser beam irradiating unit 20 toward the output measuring unit 50 exceeds a predetermined value. The laser beam output from the laser beam irradiation means 20 is determined to exceed a predetermined value, and if the output is less than a predetermined value, the laser beam output from the laser beam irradiation means 20 is determined in advance. It is determined that the predetermined output is not exceeded.

  When the laser beam output from the laser beam irradiation unit 20 exceeds a predetermined output, the control unit 90 opens the opening / closing valve 80 immediately after performing laser processing on the workpiece W, After the workpiece W is sucked and held on the table 10, the workpiece W is ablated. Further, when the output of the laser beam from the laser beam irradiation unit 20 does not exceed a predetermined output, the control unit 90 displays it on a display unit or the like, and the operator outputs the predetermined output of the laser beam irradiation unit 20 to the operator. Informs that the output of is not exceeded. Thus, when measuring the output of the laser beam by the output measuring means 50 before processing the workpiece W, the control means 90 closes the opening / closing valve 80, and the dust processing device 70 and the dust discharging means 60 are in communication. Cut off.

  As described above, in the laser processing apparatus 1 according to the present embodiment, the opening / closing valve 80 is disposed between the dust discharging means 60 and the dust processing apparatus 70, and the control means 90 outputs the laser beam by the output measuring means 50. The open / close valve 80 is closed during measurement. For this reason, when measuring the output of the laser beam, even if the blower of the dust processing device 70 is operated, it is possible to restrict the atmosphere around the output measuring means 50 from flowing. Therefore, it is possible to suppress the output measuring unit 50 from being cooled by the flow of the surrounding atmosphere, and the laser beam irradiated from the laser beam irradiation unit 20 and received by the output measuring unit 50 is the atmosphere around the output measuring unit 50. Therefore, the output measuring means 50 can accurately measure the output of the laser beam. Therefore, even when measuring the output of the laser beam between the laser processing of the workpiece W, the open / close valve disposed between the dust processing device and the dust discharging means is operated from beginning to end. By closing 80, the output measuring means 50 can accurately measure the output of the laser beam.

  Even if the blower of the dust processing device 70 is operated during the measurement of the output of the laser beam, the output measuring unit 50 can accurately measure the output of the laser beam by closing the opening / closing valve 80. To this end, after operating the blower of the dust processing apparatus 70 from beginning to end, closing the opening / closing valve 80 and measuring the output of the laser beam by the thermal output measuring means, opening the opening / closing valve 80 and starting laser processing, Immediately, the discharge of dust by the dust discharge means 60 is started. For this reason, when measuring the output of the laser beam by the output measuring means 50, the blower of the dust processing device 70 can be driven stably, and the dust can be discharged immediately after measuring the output of the laser beam, and laser processing can be performed. Can be done. Therefore, the downtime at the time of laser processing can be reduced as much as possible, and a decrease in work efficiency can be suppressed. Therefore, the output of the laser beam can be accurately measured, and laser processing can be performed immediately after the measurement.

  Further, the dust treatment device 70 sucks the exhaust gas containing dust into the treatment tank 72 partitioned into an introduction chamber in which water is sprayed and a separation chamber communicated with the introduction chamber. Can be captured in the treatment tank 72. Moreover, since the dust heated by the laser beam irradiation is cooled by the water in the treatment tank 72, it is possible to suppress the dust accumulated in the treatment tank 72 from generating heat.

  In the above embodiment, an open / close valve is provided for communicating and blocking between the dust discharge means 60 and the dust treatment device 70. However, in the present invention, one opening / closing port communicates with the dust discharge means 60 as the open / close valve. Alternatively, a three-way valve may be used in which one inlet / outlet communicates with the treatment tank 72 of the dust treatment apparatus 70 and the remaining inlet / outlet is open to the atmosphere. In this case, when measuring the output of the laser beam, the control means 90 connects either the doorway opened to the atmosphere or the remaining two doorways to block the communication between the dust discharge means 60 and the dust treatment device 70. To do. When laser processing of the workpiece W is performed by the laser beam irradiation means 20, the dust discharge means 60 and the dust treatment device 70 may be communicated with each other by connecting two entrances other than the entrance / exit opened to the atmosphere. As described above, in the present invention, the opening / closing valve 80 is referred to as communication between the dust discharging means 60 and the dust processing device 70, and the communication between the dust discharging means 60 and the dust processing device 70 is blocked. It is said that the valve 80 is closed.

  Moreover, in the said embodiment, the dust processing apparatus 70 which attracts | sucks the exhaust gas containing dust in the processing tank 72 divided into the introduction chamber in which water is sprayed and the separation chamber connected to the introduction chamber as a dust processing apparatus. However, the present invention is not limited to this. In the present invention, for example, a dust treatment device in which a blower provided between filters provided at intervals is connected to the discharge pipe 65 may be used.

  Furthermore, in the above-described embodiment, a so-called thermal output measuring unit is used as the output measuring unit 50, but the present invention is not limited to this. That is, as the output measuring unit, an output measuring unit that measures the output of the laser beam irradiated from the condenser 22 of the laser beam irradiating unit 20 by outputting information corresponding to the amount of the received laser beam may be used.

DESCRIPTION OF SYMBOLS 1 Laser processing apparatus 10 Chuck table 20 Laser beam irradiation means 22 Condenser 50 Output measurement means 60 Dust discharge means 65 Discharge pipe 70 Dust processing apparatus 71 Duct 80 On-off valve 90 Control means W Workpiece

Claims (1)

A chuck table for holding a workpiece, and a laser beam irradiation means including a condenser for irradiating the surface of the workpiece held on the chuck table with a laser beam to form a laser processing groove by ablation processing; Dust disposed at the end of the light collector on the downstream side in the direction of laser beam irradiation and for sucking and discharging dust generated near the processing point by the laser beam irradiated onto the workpiece by the light collector A laser processing apparatus comprising a discharging means,
Output measuring means for measuring the output of the laser beam emitted from the condenser;
A dust treatment device connected to the dust discharge means via a discharge pipe and capturing dust contained in the exhaust and discharging only the exhaust into the duct;
An on-off valve disposed between the dust discharge means and the dust treatment device;
Control means for controlling the open / close valve,
When measuring the output of the laser beam with the output measuring means before processing the workpiece, the control means closes the open / close valve and the dust treatment device and the dust discharge means shut off communication,
When the workpiece is processed by the laser beam irradiation means, the opening / closing valve opens and the dust treatment device and the dust discharge means communicate with each other, and a suction force acts near the processing point to discharge dust generated by the processing. A laser processing device characterized by that.

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