JP2012030268A - Laser machining apparatus and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser machining apparatus for laser machining capable of restricting the generation of cracks inside a workpiece.SOLUTION: The laser machining apparatus 1 is an apparatus for executing laser machining for a workpiece 50 made of glass or crystal and includes: a laser light source 12 for emitting a laser beam; a control means 10 for controlling the emission conditions of the laser beam; and light collecting means 16, 19 for collecting the laser beam into the workpiece. The control means 10 controls the emission conditions of the laser beam so that (i) when the workpiece is glass, pulse peak output of the laser beam is made at least 25 times larger than a mean output, and (ii) when the workpiece is crystal, the pulse peak output of the laser beam is made at least six times larger than the mean output.

Description

  The present invention relates to a technical field of a laser processing apparatus and method for processing a workpiece by using, for example, laser light.

  As this type of apparatus, a processing apparatus that focuses a laser beam on the surface or inside of a processing object such as a substrate made of a material such as glass or quartz, and forms a chemically or physically modified region by multiphoton absorption. It has been known. An electronic component such as a chip can be formed by dividing the substrate by applying a procedure such as cleavage with the modified region as a starting point after processing by the processing apparatus. In such a laser processing apparatus, various ideas have been made in order to improve processing accuracy.

  The presence of cracks formed in the object to be processed by laser light can be cited as a cause of deterioration in processing accuracy. It is known that the modification mode in the modified region changes depending on the output of the laser beam absorbed by the workpiece and the emission time. Progresses and unnecessary cracks may occur. In addition, the crack generation conditions change due to brittle changes in accordance with the material of the workpiece.

  Prior art documents to be described later describe a technique that suppresses excessive heating and makes it difficult to generate cracks by providing a non-irradiation period of pulsed laser light when condensing laser light inside a workpiece. Has been.

JP-A-11-123777

  In laser processing using a brittle material such as glass or quartz as a processing target, cracks are likely to occur due to the emission of laser light as described above, and therefore processing accuracy is low. The factors include the fact that cracks extend to a region outside the laser light emission region within the workpiece due to brittleness, and that the accuracy of the action of thermal stress during the cutting process is low.

  The present invention has been made in view of the above-mentioned problems, for example, and a laser processing apparatus and method capable of improving processing accuracy in laser processing when a brittle material such as glass or quartz is used as a processing target. It is an issue to provide.

  In order to solve the above-described problems, a first laser processing apparatus of the present invention is a laser processing apparatus that performs laser processing using glass or quartz as an object to be processed, and includes a laser light source that emits laser light, A control means for controlling emission conditions; and a condensing means for condensing the laser light onto the workpiece, wherein the control means (i) when the glass is used as the workpiece, When the pulse peak output is 25 times or more with respect to the average output, and (ii) quartz is used as the object to be processed, the laser beam is set so that the pulse peak output of the laser light is 6 times or more with respect to the average output. The emission conditions are controlled.

  In order to solve the above problems, a second laser processing apparatus of the present invention is a laser processing apparatus that performs laser processing using glass or quartz as an object to be processed, and includes a laser light source that emits laser light, Control means for controlling the emission conditions; condensing means for condensing the laser beam on the workpiece; and splitting means for dividing the workpiece using a modified region formed by the laser beam; And (i) when glass is used as the processing object, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) crystal is used as the processing object. In this case, the laser beam emission conditions are controlled so that the pulse peak output of the laser beam is 6 times or more of the average output, and the dividing means branches the laser beam and the branched laser beam 0.5 millimeters or more, is converged to a position corresponding to the modified region in the beam diameter 5 millimeters or less is formed on the workpiece.

  In order to solve the above problems, a first laser processing method of the present invention is a laser processing method for laser processing using glass or quartz as an object to be processed, and controls emission conditions of a laser light source that emits laser light. A control step, and a condensing step of condensing the laser beam on the workpiece, wherein the control step (i) when using glass as the workpiece, the pulse peak output of the laser beam, More than 25 times the average output, and (ii) when using quartz as the workpiece, the laser beam emission conditions are controlled so that the pulse peak output of the laser light is 6 times or more the average output. To do.

  In order to solve the above problems, a second laser processing method of the present invention is a laser processing method for laser processing using glass or quartz as an object to be processed, and controls the emission conditions of a laser light source that emits laser light. A control step, a condensing step of condensing the laser beam on the workpiece, and a dividing step of dividing the workpiece using a modified region formed by the laser beam, the control In the step (i), when glass is used as the processing object, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) when the crystal is used as the processing object, the laser light The laser beam emission conditions are controlled so that the pulse peak output of the laser beam becomes 6 times or more of the average output. In the dividing step, the laser beam is branched, and the branched laser beam is reduced to 0.5. Millime Torr or higher, is converged to a position corresponding to the modified region in the beam diameter 5 millimeters or less is formed on the workpiece.

It is a block diagram which shows the basic composition of the laser processing apparatus of an Example. It is a figure which shows a pulsed laser beam. It is a block diagram which shows the basic composition of the laser processing apparatus of a modification.

  1st Embodiment of the laser processing apparatus of this invention is a laser processing apparatus which laser-processes glass or quartz as a processing target object, Comprising: Control which controls the laser light source which radiate | emits a laser beam, and the emission conditions of the said laser beam Means, and a condensing means for condensing the laser beam on the workpiece, the control means (i) when using glass as the workpiece, the pulse peak output of the laser beam is averaged More than 25 times the output, and (ii) when using quartz as the workpiece, the laser beam emission conditions are controlled so that the pulse peak output of the laser beam is 6 times or more the average output. .

  According to the first embodiment of the laser processing apparatus of the present invention, the processing object is irradiated with laser light, and the laser light is condensed on the surface or inside of the processing object, so that it is near the condensing unit. It causes physical or chemical modification such as by heating. Since the modified region in the object to be processed is generally brittle as compared with other parts, it is possible to easily perform processing such as division by using the modified region as a starting point.

  More specifically, in the laser light irradiation region (specifically, near the condensing portion) of the workpiece, during the laser light irradiation, after being vaporized by a short rapid heating, A series of state changes occur. At this time, due to a series of state changes, rapid thermal expansion occurs in the heated state, and rapid convergence in the supercooled state forms portions with different volumes or densities in the irradiated region, and the solidified state in the irradiated region. The part which becomes becomes. Due to the solidification, the laser light irradiation region is modified, and the workpiece becomes more brittle. Also, cracks may occur due to stress concentration due to convergence.

  In particular, when a brittle material such as glass or quartz is used as an object to be processed, there is a possibility that cracks may extend outside the irradiation region when the above-described series of state changes occur due to laser irradiation in the irradiation region. Are known. This is due to the increase in the laser beam absorption energy in the workpiece due to the increase in the laser beam output and irradiation time, and the surplus after vaporizing the workpiece in the vicinity of the condensing part. This is because energy is accumulated as heat in the peripheral portion. The heat accumulated in this manner causes thermal expansion inside the workpiece, and causes unintentional cracks (that is, in regions other than the modified region formed by laser light irradiation). Inside a brittle material such as glass or quartz, a crack easily propagates inside the brittle material even with a relatively small force. Therefore, when such an unintended crack extends into the workpiece, the strength of the brittle material is reduced. This significantly reduces the processing accuracy.

  In the first embodiment of the laser processing apparatus of the present invention, the emission conditions in the laser light source that emits the laser light are controlled by the control means. Specifically, the control means determines the average output of the pulsed laser beam and the output at the peak of the pulse according to the material of the workpiece (in other words, parameters related to the machining accuracy such as brittleness of the workpiece). The drive of the laser light source is controlled so that the ratio of the above satisfies a predetermined standard.

  For example, when the workpiece is glass, the control means sets the output at the peak of the pulsed laser beam to 25 times or more of the average output. Further, when the object to be processed is quartz, the output at the peak of the pulsed laser beam is set to 6 times or more than the average output.

  In such a setting, in the laser light irradiation region, the surface of the workpiece or the internal irradiation region is modified by vaporization or the like due to the high-power peak laser light with relatively high energy. , Suitable processing becomes possible. On the other hand, at the non-peak time, the amount of energy absorbed by the laser beam in the workpiece is relatively low compared to the peak time, so that the heat accumulated in the irradiation region is released and the temperature rise is suitably performed. It can be prevented.

  By setting the output of the pulsed laser beam as described above, it is possible to suitably release the heat accumulated inside the workpiece, and it is possible to suppress the generation and extension of cracks due to thermal expansion. By performing such laser processing, it is possible to limit the region where the modification including cracks or the like occurs according to the laser light irradiation region and the emission condition, leading to improvement in processing accuracy. In addition, when further processing such as parting of the workpiece is performed starting from such a modified region, high-accuracy cutting is possible by modification including cracks that occur intensively in the restricted region. It becomes. For this reason, it is possible to prevent deterioration of processing accuracy due to cracks generated in an unintended region, and it is possible to suitably realize various processings starting from a modified region formed with high accuracy.

  In one aspect of the first embodiment of the laser processing apparatus of the present invention, the control means controls the average output of the laser beam to 0.01 W or more and 4 W or less when glass is used as the processing object.

  According to this aspect, it is possible to appropriately set the emission condition of the pulsed laser beam when performing laser processing using glass as a processing object. Therefore, it is possible to suppress the deterioration of the processing accuracy due to the unintended crack progress and realize high-precision processing.

  In another aspect of the first embodiment of the laser processing apparatus of the present invention, when the condensing means uses glass as the processing target, the beam diameter of the laser light on the processing target is 40 micrometers or more, The laser beam is condensed so as to be 140 micrometers or less.

  According to this aspect, it is possible to appropriately set the emission condition of the pulsed laser beam when performing laser processing using glass as a processing object. Therefore, it is possible to suppress the deterioration of the processing accuracy due to the unintended crack progress and realize high-precision processing.

  In another aspect of the first embodiment of the laser processing apparatus of the present invention, the laser processing apparatus further includes moving means for moving the object to be processed relative to the laser beam, and the moving means includes glass as the object to be processed. In this case, the object to be processed is moved relative to the laser light at a speed of 0.01 millimeter / second or more and 3 millimeter / second or less.

  According to this aspect, it is possible to appropriately set the moving condition of the processing object when performing laser processing using glass as the processing object. Therefore, it is possible to suppress the deterioration of the processing accuracy due to the unintended crack progress and realize high-precision processing.

  In another aspect of the first embodiment of the laser processing apparatus of the present invention, the control means controls the average output of the laser beam to 0.1 W or more and 10 W or less when crystal is the processing object. The laser processing apparatus according to claim 1.

  According to this aspect, it is possible to appropriately set the emission condition of the pulsed laser beam when performing laser processing using quartz as a processing object. Therefore, it is possible to suppress the deterioration of the processing accuracy due to the unintended crack progress and realize high-precision processing.

  In another aspect of the first embodiment of the laser processing apparatus of the present invention, when the condensing means uses quartz as the processing target, the beam diameter of the laser light on the processing target is 40 micrometers or more, The laser beam is focused so as to be 300 micrometers or less.

  According to this aspect, it is possible to appropriately set the emission condition of the pulsed laser beam when performing laser processing using quartz as a processing object. Therefore, it is possible to suppress the deterioration of the processing accuracy due to the unintended crack progress and realize high-precision processing.

  In another aspect of the first embodiment of the laser processing apparatus of the present invention, the laser processing apparatus further includes moving means for moving the object to be processed relative to the laser beam, and the moving means includes a crystal as the object to be processed. In this case, the workpiece is moved relative to the laser light at a speed of 0.01 millimeter / second or more and 50 millimeter / second or less.

  According to this aspect, it is possible to appropriately set the moving condition of the processing object when performing laser processing using quartz as the processing object. Therefore, it is possible to suppress the deterioration of the processing accuracy due to the unintended crack progress and realize high-precision processing.

  In another aspect of the first embodiment of the laser processing apparatus of the present invention, the laser light source is a carbon dioxide laser light source.

  Compared to the processing of hard glass and the like that require an expensive laser with a relatively high pulse repetition frequency, such as a conventional FS (Femto Second) laser or PS (Pico Second) laser, by satisfying the above emission conditions. An inexpensive carbon dioxide laser can be used. Further, according to this aspect, the above-described laser light pulse control and output control can be realized relatively easily.

  The second embodiment of the laser processing apparatus of the present invention is a laser processing apparatus that performs laser processing using glass or quartz as an object to be processed, and includes a laser light source that emits laser light and a control that controls the emission conditions of the laser light. Means for condensing the laser beam on the object to be processed, and dividing means for dividing the object to be processed using a modified region formed by the laser beam, the control means (I) When glass is used as the object to be processed, the pulse peak output of the laser light is 25 times or more of the average output. (Ii) When quartz is used as the object to be processed, The laser beam emission conditions are controlled so that the pulse peak output is 6 times or more of the average output, and the dividing means divides the laser beam and the branched laser beam is 0.5 mm. Le or condenses at a position corresponding to the modified region in the beam diameter 5 millimeters or less is formed on the workpiece.

  According to the second embodiment of the laser processing apparatus of the present invention, similarly to the first embodiment of the laser processing apparatus of the present invention described above, the processing for forming the modified region is performed on the workpiece. I can do it.

  The dividing means of the second embodiment of the laser processing apparatus branches the laser light emitted from the processing laser light source and condenses it along the divided section in the modified region of the processing object. The dividing means generates thermal stress due to heating in the minute volume in the modified region of the workpiece by the light collection, and performs thermal stress separation starting from the modified region by the thermal stress.

  According to the second embodiment of the laser processing apparatus, by using an apparatus having one laser light source, the first processing for forming the modified region on the object to be processed, and the processing using the modified region. A second process for dividing the object can be performed.

  Incidentally, in response to the various aspects that the laser processing apparatus of the first embodiment can take, the laser processing apparatus of the second embodiment can also adopt various aspects.

  In one aspect of the second embodiment of the laser processing apparatus of the present invention, the dividing means is formed on the processing object when the condensing means condenses the laser light on the processing object. The branched laser beam is condensed at a position corresponding to the modified region.

  According to this aspect, the first processing for forming the modified region by the processing laser beam and the second processing for dividing the workpiece by thermal stress starting from the modified region are performed in parallel. Can be implemented. Accordingly, it is possible to reduce the tact time required for a series of dividing processes including the formation and dividing of the modified region when dividing the workpiece.

  1st Embodiment of the laser processing method of this invention is a laser processing method which laser-processes glass or quartz as a processing target object, Comprising: The control process which controls the emission conditions of the laser light source which radiate | emits a laser beam, and said laser beam A light condensing step for condensing the laser beam on the object to be processed, and the control step (i) when using glass as the object to be processed, the pulse peak output of the laser beam is 25 times the average output. As described above, (ii) in the case where quartz is used as the workpiece, the laser beam emission conditions are controlled so that the pulse peak output of the laser beam is 6 times or more the average output.

  According to the first embodiment of the laser processing method of the present invention, using the laser processing apparatus, it is possible to obtain the same effect as that of the first embodiment of the laser processing apparatus of the present invention described above. In addition, also about 1st Embodiment of the laser processing method of this invention, you may employ | adopt the various aspects similar to the various aspects of 1st Embodiment of the laser processing apparatus of this invention mentioned above.

  A second embodiment of the laser processing method of the present invention is a laser processing method for laser processing using glass or quartz as an object to be processed, the control step for controlling the emission conditions of a laser light source for emitting laser light, and the laser A condensing step of condensing light on the workpiece, and a dividing step of dividing the workpiece using a modified region formed by the laser beam, the control step comprising (i) When glass is the processing object, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) when quartz is the processing object, the pulse peak output of the laser light is The laser beam emission conditions are controlled so that the average output is 6 times or more. In the dividing step, the laser beam is branched, and the branched laser beam is 0.5 mm or more and 5 mm or more. Toru is converged at a position corresponding to the modified region formed in the workpiece by the following beam diameter.

  According to the second embodiment of the laser processing method of the present invention, using the laser processing apparatus, it is possible to obtain the same effect as that of the above-described second embodiment of the laser processing apparatus of the present invention. In addition, also about 2nd Embodiment of the laser processing method of this invention, you may employ | adopt the various aspects similar to the various aspects of 1st Embodiment of the laser processing apparatus of this invention mentioned above.

  As described above, the first embodiment of the laser processing apparatus of the present invention includes the laser light source, the condensing unit, and the control unit. The second embodiment of the laser processing apparatus of the present invention includes a laser light source, a condensing unit, a control unit, and a dividing unit. 1st Embodiment of the laser processing method of this invention is provided with a condensing process and a control process. 2nd Embodiment of the laser processing method of this invention is equipped with a condensing process, a control process, and a cutting process.

  For this reason, in laser processing in the case where a brittle material such as glass or quartz is used as a processing object, it is possible to suitably suppress the occurrence of unintended cracks and improve processing accuracy.

  Embodiments of the present invention will be described below with reference to the drawings.

(1) Configuration of Laser Processing Apparatus First, a basic configuration of a laser processing apparatus 1 that is an example of the laser processing apparatus of the present invention will be described with reference to FIG.

  As shown in FIG. 1, the laser processing apparatus 1 includes a control unit 10, a laser power source 11, a laser light source 12, a mirror 13, a half-wave plate 14, a mirror 15, and a beam expander 16. A beam combiner 17, a lens block 18, and a condenser lens 19. The laser processing apparatus 1 includes a guide laser diode (LD) 21 and a guide optical system 22.

  The control unit 10 is an example of a control unit of the present invention, and includes a CPU that controls the operation of each unit of the laser processing apparatus 1. The control unit 10 controls the operations of the laser power source 11 and the laser light source 12 so as to emit laser light L1 that is pulse-like and satisfies emission conditions such as a predetermined repetition frequency, average output, and pulse peak output. Further, the control unit 10 controls the operation of the lens block 18 so as to change the beam diameter of the condensing unit F1 of the laser light L1 in accordance with the processing of the workpiece 50 by the emission of the laser light L1. Moreover, the control part 10 performs control which moves the stage 40 which mounts the workpiece 50 in the surface orthogonal to the optical axis direction of the laser beam L1, etc. with the emission of the laser beam L1.

  The laser power source 11 includes a power source for supplying power for driving the laser light source 12 and a pulse control device. For example, the laser power source 11 receives an instruction input by a user and supplies current to the laser light source in a desired manner. Do and drive.

  The laser light source 12 is an example of the laser light source of the present invention, and includes a laser generation unit, a concentrating element, a phase modulator, a resonator, and the like, and generates laser light L1 according to a current supplied from the laser power source 11. , Exits in the direction of the mirror 13. The laser light source 12 is preferably a light source excellent in pulse control and output control, for example, a carbon dioxide laser light source that adds circularly polarized light or linearly polarized light having a maximum output of about 100 W.

  The laser light L1 emitted from the laser light source 12 is adjusted in phase difference (or polarization state) in the half-wavelength plate 14 via the mirror 13 and then enters the beam expander 16 via the mirror 15. .

  The beam expander 16 is an example of a component of the light condensing unit of the present invention, and is a mechanism that expands the beam diameter of the laser light L1 that is incident in the form of parallel light. Specifically, the beam expander 16 adjusts so that the beam diameter of the condensing part F1 in the processing target object 50 of the laser light L1 is within a predetermined range together with the condensing by the condensing lens 19 described later. . The expansion ratio of the beam diameter by the beam expander 16 is set according to the aperture of the condenser lens 19 described later.

  The beam combiner 17 is a half mirror or the like that combines the laser beam L1 on the same optical path by transmitting the laser beam L1 and reflecting the laser beam L2 for guide.

  The guide laser beam L2 is a laser beam emitted from the guide LD 21, and is incorporated in the same optical path as the laser beam L1 by the beam combiner 17, and is condensed on the workpiece 50 by the condenser lens 19. Laser light for distance measurement or servo drive. On the optical path of the laser beam L2, a guide optical system 22 corresponding to the application, such as a beam forming lens, a condenser lens, or a cylindrical lens, is disposed.

  The lens block 18 is a lens unit that holds the condenser lens 19 and includes a slide mechanism that moves the condenser lens 19 in the optical axis direction of the laser light L1.

  The condensing lens 19 is a lens that mainly condenses the laser light L1 on the surface or inside of the workpiece 50 and typically forms the condensing part F1 at the focal position. The aperture of the condenser lens 19 is preferably set in accordance with the beam diameter of the condenser part F1. The lens block 18 is formed at a desired position on the surface of the workpiece 50 or inside by moving the condenser lens 19 in the optical axis direction of the laser light L1 in accordance with a control signal from the control unit 10, for example. The beam diameter of the condensing part F1 is adjusted.

  The stage 40 is a mounting table on which the workpiece 50 is placed, and includes a mechanism that can move the workpiece 50 in a plane orthogonal to the optical axis direction of the laser light L1. For example, the stage 40 moves the workpiece 50 relative to the condensing unit F1 of the laser light L1 at a speed according to the control signal supplied from the control unit 10.

(2) Processing conditions The control part 10 of the laser processing apparatus 1 grasps | ascertains the material of the processing target object 50 (as a result, the property depending on the material of the processing target object 50, such as brittleness), for example according to the input from a user. Then, the mode of operation of each part is set so as to satisfy the processing conditions according to the material.

  In the laser processing apparatus 1, the control unit 10 responds to at least two processing conditions, that is, a processing condition A when the glass is the processing target 50 and a processing condition B when the crystal is the processing target 50. The mode of operation of each part can be set. As will be described below, the mode of operation of each main part to be controlled by the control unit 10 includes (1) a pulse peak output ratio with respect to the average output of the pulsed laser light L1, and (2) an average of the laser light L1. Output, (3) relative speed when moving the stage 40 (and hence the workpiece 50) with respect to the condensing part F1 of the laser light L1 during processing, and (4) the beam diameter of the condensing part F1 of the laser light L1. It is.

  Processing conditions A when the material of the processing object 50 is glass will be described. The control unit 10 controls the mode of operation of each unit so as to satisfy any of conditions A1 to A4 described below or an appropriately combined processing condition during laser processing using glass as the processing object 50.

  The controller 10 preferably controls the operation of the laser light source 12 so that the output at the time of the pulse peak of the laser light L1 is 25 times or more of the average output (condition A1).

  More preferably, the control unit 10 controls the operation of the laser light source 12 so that the average output of the laser light L1 is 0.01 W or more and 4 W or less (Condition A2). Here, the average output is an average value of outputs per one cycle of the pulsed laser beam L1. FIG. 2 shows an example of time-series changes in the output of the pulsed laser beam L1.

  More preferably, the control unit 10 is configured so that the relative movement speed of the stage 40 with respect to the light condensing unit F1 is 0.01 millimeter / second or more and 3 millimeter / second or less when the workpiece 50 is processed by irradiation with the laser beam L1. The operation of the stage 40 is controlled (condition A3).

  More preferably, the control unit 10 further preferably uses the beam expander 16 so that the beam diameter of the condensing unit F1 formed on the surface or inside of the workpiece 50 of the laser light L1 is 40 micrometers or more and 140 micrometers or less. And the operation of the lens block 18 is controlled (condition A4).

  The processing performed by the inventors of the present application when processing hard glass (optical glass) by irradiating with laser light L1 in a setting satisfying the processing conditions defined in the above-described conditions A1 to A4. The evaluation will be described. With respect to the processing object 50, those that do not cause cracks outside the irradiation region due to irradiation with the laser light L1 are classified as good processing, and those that cause cracks outside the modified region are classified as defective processing. For condition A1, good machining is observed in the region where the output at the pulse peak is 25 times or more of the average output, while good machining is observed in the region where the output at the pulse peak is less than 25 times the average output. Not observed.

  Regarding condition A2, good processing was observed in the region where the average output of the laser beam L1 was 4 W or less, but good processing was not observed in the region where the average output exceeded 4 W. In addition, in the region where the average output of the laser beam L1 is less than 0.01 W, the workpiece 50 was not modified.

  Regarding condition A3, good processing is observed in the region where the relative movement speed of the stage 40 is 3 millimeters per second or less, while good processing is not observed in the region where the relative movement speed of the stage 40 exceeds 3 millimeters per second. It was. Further, in the region where the relative movement speed of the stage 40 is 0.01 millimeter per second or less, the processing takes a long time, which is not preferable as a processing machine.

  Regarding condition A4, good processing is observed in the range where the beam diameter of the condensing part F1 is 40 micrometers or more and 140 micrometers or less, but in the processing where the beam diameter is out of the range, good processing is observed. Was not.

  Processing conditions when the material of the processing object 50 is quartz will be described. The control unit 10 controls the mode of operation of each unit so as to satisfy any of the conditions B1 to B4 described below or a combination of processing conditions as appropriate during laser processing using quartz as the processing object 50.

  Preferably, the control unit 10 controls the operation of the laser light source 12 so that the output at the pulse peak of the laser light L1 is 6 times or more the average output (Condition B1).

  More preferably, the control unit 10 controls the operation of the laser light source 12 so that the average output of the laser light L1 is not less than 0.1 W and not more than 10 W (condition B2).

  More preferably, the control unit 10 causes the relative movement speed of the stage 40 to the condensing unit F1 to be 0.01 millimeter / second or more and 50 millimeter / second or less when the workpiece 50 is processed by irradiation with the laser beam L1. The operation of the stage 40 is controlled (condition B3).

  More preferably, the control unit 10 sets the beam expander 16 so that the beam diameter of the condensing unit F1 formed on the surface or inside of the workpiece 50 of the laser light L1 is 40 micrometers or more and 300 micrometers or less. And the operation of the lens block 18 is controlled (condition B4).

  An explanation will be given of the evaluation of the processing performed by the inventors of the present application when processing is performed by irradiating the laser beam L1 on the crystal with the setting satisfying the processing conditions defined in the above-described conditions B1 to B4. With respect to the processing object 50, those that do not cause cracks outside the irradiation region due to irradiation with the laser light L1 are classified as good processing, and those that cause cracks outside the modified region are classified as defective processing. Regarding condition B1, good machining is observed in the region where the output at the pulse peak is 6 times or more of the average output, while good machining is observed in the region where the output at the pulse peak is less than 6 times the average output. Not observed.

  Regarding condition B2, good processing was observed in the region where the average output of the laser beam L1 was 10 W or less, but good processing was not observed in the region where the average output exceeded 10 W. In addition, in the region where the average output of the laser beam L1 is less than 0.1 W, the workpiece 50 was not modified.

  Regarding condition B3, good machining is observed in the region where the relative movement speed of the stage 40 is 50 millimeters per second or less, while good machining is not observed in the region where the relative movement speed of the stage 40 exceeds 50 millimeters per second. It was. Further, in the region where the relative movement speed of the stage 40 is 0.01 millimeter per second or less, the processing takes a long time, which is not preferable as a processing machine.

  Regarding condition B4, good processing is observed in the range where the beam diameter of the condensing part F1 is 40 micrometers or more and 300 micrometers or less, while in the processing where the beam diameter is out of the range, good processing is observed. Was not.

  Here, (1) the peak output ratio 133 with respect to the average output of the laser beam L1, (2) the average output of the laser beam L1 is 0.56 W, (3) the relative movement speed of the stage 40 is 0.1 millimeter per second, and (4) The results obtained will be described by taking as an example the case of irradiating the hard glass with the laser light L1 under the condition of a beam diameter of 68 micrometers (design value) in the condensing part F1. At this time, a modified region having a width of 100 micrometers was formed along the condensing region of the laser beam L1, and a plurality of cracks were observed in the modified region. On the other hand, the development of cracks of 100 micrometers or more outside the modified region was not observed. When the hard glass was divided from the formed modified region as a starting point, a sectional surface that became a mirror surface along the irradiated region was obtained, and the outer dimension tolerance was less than 60 micrometers.

  Further, since the modified region is brittle, the modified glass remaining on the sectional surface after the division can be removed relatively easily. For example, traces such as cracks can be eliminated by removing an area of about 100 micrometers from the sectional surface after cutting by polishing or the like.

  In addition, when using the processing conditions mentioned above, even if it is a case where irradiation area | regions cross | intersect by irradiation of the laser beam L1 several times, the influence of the progress of the crack in the formed modification | reformation area | region, etc. does not arise. For this reason, the freedom degree of a process can be guaranteed.

(3) Modification A laser processing apparatus 1 ′, which is a modification of the laser processing apparatus 1, will be described. FIG. 3 is a diagram showing a configuration of the laser processing apparatus 1 ′. In FIG. 3, the same reference numerals as those in FIG. 1 may have the same configuration as that of the laser processing apparatus 1 shown in FIG. For example, similarly to the laser processing apparatus 1, the laser processing apparatus 1 ′ includes a control unit 10, a laser power source 11, a laser light source 12, a mirror 13, a half-wave plate 14, a beam expander 16, and a beam. A combiner 17, a lens block 18, a condenser lens 19, a guide laser diode (LD) 21, and a guide optical system 22 are provided.

  Further, the laser processing apparatus 1 ′ includes a polarization beam splitter 31 as a configuration replacing the mirror 15. The polarization beam splitter 31 reflects a part of the laser light L1 that has passed through the half-wave plate 14 in the direction of the beam expander 16, while branching a part of the laser light L1 as a splitting laser light L3. The light is transmitted in the direction of the mirror 32. The mirror 32 reflects the laser light L3 so as to enter the beam expander 33.

  The beam expander 33 is a structural example of the dividing means in the second embodiment of the laser beam of the present invention, and adjusts and emits the beam diameter of the laser beam L3 incident in a parallel light mode. Specifically, the beam expander 33 adjusts so that the beam diameter of the condensing part F3 in the processing object 50 of the laser light L3 is within a predetermined range, together with the condensing by the condensing lens 19. The expansion ratio of the beam diameter of the laser beam L3 by the beam expander 33 is set according to the aperture of the condenser lens 19 described later.

  The laser beam L3 emitted from the beam expander 33 is transmitted through the splitting optical system 34 according to the application such as a beam forming lens, a condensing lens, or a cylindrical lens disposed on the optical path in the polarization beam splitter 36. It is synthesized on the same optical path as the laser beam L1. The polarization beam splitter 36 transmits the laser beam L3, while being emitted from the beam expander 16, reflects the laser beam L1 whose optical axis is adjusted by the mirror 35, and synthesizes them on the same optical path.

  The laser light L1 and the laser light L3 traveling on the same optical path are condensed on the surface or inside of the workpiece 50 by the condenser lens 19 to form the condenser parts F1 and F3, respectively. In the condensing part F1, the modified region is formed by vaporization or the like on the surface or inside of the workpiece 50 due to the energy absorption of the laser beam L1. On the other hand, in the condensing part F3, the inside of the modified region formed on the surface or inside of the workpiece 50 is heated by the energy absorption of the laser beam L3, and stress due to thermal expansion occurs. At this time, due to the stress concentrated in the embrittled modified region, the workpiece 50 is divided starting from the modified region.

  The output and the beam diameter of the laser beam L1 in the condensing unit F1 are controlled by the control unit 10 according to the material of the workpiece 50. Specifically, the output and the beam diameter of the laser beam L1, and the relative movement speed of the stage 40 with respect to the condensing part F1 satisfy the above-described processing conditions.

  Similarly, the output and beam diameter of the laser beam L3 in the condensing unit F3 are under the control of the control unit 10 according to the material of the workpiece 50. In order to generate stress on the surface or the inside of the workpiece 50, the control unit 10 preferably sets, for example, the laser beam L3 for cutting in a range of an average output of 20 W or more and 100 W or less, and a beam in the light collecting unit F3. The diameter is set in the range of 0.5 mm to 5 mm. In addition, the division | segmentation of the process target object 50 which is a hard glass or a crystal | crystallization is confirmed on the above-mentioned conditions by the experiment of the process performed by this inventor.

  As described above, the laser processing apparatus 1 ′ forms the modified region on the surface or inside of the workpiece 50 by irradiating the processing laser beam L <b> 1. In addition, the laser processing apparatus 1 ′ irradiates the modified region with a laser beam L3 for splitting that is branched from the laser beam L1, thereby generating stress due to thermal expansion in the modified region, thereby forming the modified region. Divide from the starting point. Therefore, the laser processing apparatus 1 ′ maintains the same processing accuracy as the laser processing apparatus 1 described above, and the first processing for forming the modified region on the surface or inside of the processing target object 50 and the embrittled It becomes possible to perform the 2nd process which divides the process target object 50 with a thermal stress from the modification | reformation area | region as a starting point. This is beneficial in terms of device arrangement at the site where the workpiece 50 is processed.

  For example, the laser processing apparatus 1 ′ may perform the first processing and the second processing at the same time. In this case, in addition to the above-described advantages, a series of processing for dividing the processing object 50 is required. It has the further advantage of reduced tact time.

  The first process and the second process may be performed at different timings. In this case, the laser processing apparatus 1 ′ applies a shutter to the optical path of each laser beam so that one of the processing laser beam L1 and the splitting laser beam L3 is irradiated to the workpiece 50 while the other is not irradiated. You may have.

  The present invention is not limited to the above-described embodiments, and can be changed as appropriate without departing from the scope or spirit of the invention that can be read from the claims and the entire specification. And the method are also included in the technical scope of the present invention.

1 Laser processing equipment,
10 control unit,
11 Laser power source 12 Laser light source,
13, 15 mirror,
14 1/2 wavelength plate,
16 beam expander,
17 Beam combiner,
18 Lens block,
19 Condensing lens,
40 stages,
50 processing object,
L1 (for processing) laser light,
L2 (for guide) laser light,
L3 (for cutting) laser light.

Claims (12)

A laser processing apparatus for laser processing glass or quartz as a processing object,
A laser light source for emitting laser light;
Control means for controlling the laser light emission conditions;
Condensing means for condensing the laser beam on the workpiece,
When the control means is (i) glass as the processing object, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) when crystal is the processing object, A laser processing apparatus, wherein the laser beam emission condition is controlled so that a pulse peak output of the laser beam is 6 times or more of an average output.   2. The laser processing apparatus according to claim 1, wherein the control unit controls an average output of the laser light to 0.01 W or more and 4 W or less when glass is used as the processing object.   The condensing means condenses the laser light so that a beam diameter of the laser light on the processing object is 40 micrometers or more and 140 micrometers or less when glass is used as the processing object. The laser processing apparatus according to claim 1 or 2. A moving means for moving the workpiece relative to the laser beam;
The moving means moves the processing object relative to the laser light at a speed of 0.01 millimeter / second or more and 3 millimeter / second or less when glass is used as the processing object. The laser processing apparatus according to any one of claims 1 to 3.   2. The laser processing apparatus according to claim 1, wherein the control unit controls an average output of the laser beam to be 0.1 W or more and 10 W or less when quartz is used as the processing object.   The condensing means condenses the laser light so that a beam diameter of the laser light on the processing object is not less than 40 micrometers and not more than 300 micrometers when quartz is used as the processing object. The laser processing apparatus according to claim 1 or 6. A moving means for moving the workpiece relative to the laser beam;
The moving means moves the processing object relative to the laser light at a speed of not less than 0.01 millimeters per second and not more than 50 millimeters per second when quartz is used as the processing target. The laser processing apparatus as described in any one of Claims 1, 5, and 6.   The laser processing apparatus according to claim 1, wherein the laser light source is a carbon dioxide laser light source. A laser processing apparatus for laser processing glass or quartz as a processing object,
A laser light source for emitting laser light;
Control means for controlling the laser light emission conditions;
Condensing means for condensing the laser beam on the workpiece;
Using a modified region formed by the laser beam, and a dividing means for dividing the workpiece.
When the control means is (i) glass as the processing object, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) when crystal is the processing object, Controlling the laser beam emission conditions so that the pulse peak output of the laser beam is 6 times or more of the average output;
The dividing means branches the laser light, and the branched laser light is positioned at a position corresponding to the modified region formed on the workpiece with a beam diameter of 0.5 mm or more and 5 mm or less. A laser processing apparatus characterized by collecting light. When the condensing unit condenses the laser light on the object to be processed,
The laser processing apparatus according to claim 9, wherein the branched laser light is condensed at a position corresponding to the modified region formed on the processing object. A laser processing method for laser processing glass or quartz as a processing object,
A control step of controlling an emission condition of a laser light source that emits laser light, and a condensing step of condensing the laser light on the workpiece,
In the control step, (i) when glass is the processing target, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) when quartz is the processing target, A laser processing method, wherein the laser beam emission condition is controlled so that a pulse peak output of the laser beam is 6 times or more of an average output. A laser processing method for laser processing glass or quartz as a processing object,
A control process for controlling emission conditions of a laser light source that emits laser light;
A condensing step of condensing the laser beam on the workpiece;
Using a modified region formed by the laser beam, and a dividing step of dividing the workpiece.
In the control step, (i) when glass is the processing target, the pulse peak output of the laser light is 25 times or more of the average output, and (ii) when quartz is the processing target, Controlling the laser beam emission conditions so that the pulse peak output of the laser beam is 6 times or more of the average output;
In the dividing step, the laser beam is branched, and the branched laser beam is positioned at a position corresponding to the modified region formed on the workpiece with a beam diameter of 0.5 mm or more and 5 mm or less. The laser processing method characterized by condensing.

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