TW201341097A - Laser machining apparatus - Google Patents

Abstract

The present invention provides a laser machining apparatus having the function of correcting offset of an irradiation position of a laser ray emitted by oscillation of a laser ray oscillator. The laser machining apparatus has a chuck workbench, a laser ray irradiation member and a machining feed member. The laser ray irradiation member comprises: a laser ray oscillator used for oscillating to emit the laser ray; a condenser having a condensing lens for condensing the laser ray and irradiating the laser ray to a machined object; an optical path adjusting member arranged between the laser ray oscillator and the condenser and used for adjusting an optical path of the laser ray; a reflecting mirror used for reflecting the laser ray towards the condenser; a detection ray condensing lens used for condensing a few of detection rays transmitting the reflecting mirror; a camera shooting member used for shooting condensed light spot of the detection ray; and a control member used for calculating offset and direction of the condensed light spot of the detection ray relative to a proper position, and controlling the optical path adjusting member according to the offset and direction to locate the condensed light spot at the proper position.

Description

Laser processing device Field of invention

The present invention is a laser processing apparatus that applies laser processing to a workpiece by irradiating laser light.

Background of the invention

In the semiconductor element manufacturing step, the surface of the semiconductor wafer having a substantially disk shape is divided into a plurality of regions in accordance with a predetermined dividing line called a scribe line arranged in a lattice shape, and ICs are formed in the regions to be partitioned. , LSI and other components. Further, the semiconductor wafer is cut along the dicing street, thereby dividing the region in which the element is formed, thereby forming each semiconductor element.

In the above method of dividing a wafer such as a semiconductor wafer along a scribe line, an attempt is made to illuminate a pulsed laser beam by aligning a condensed spot with a pulsed laser beam having transparency to the inside of the region to be divided. Injection processing method. The laser processing method is a method in which a laser beam is directed from one side of the wafer to align the inside of the wafer to illuminate a pulsed laser beam having a wavelength transparent to the wafer, and is continuously continuous along the scribe line inside the wafer. The reforming layer is formed in the ground, and an external force is applied along the scribe line in which the strength is lowered by forming the reforming layer, thereby dividing the wafer.

Further, a method of dividing a wafer such as a semiconductor wafer or an optical element wafer has been proposed to irradiate a pulsed laser beam having a wavelength that is absorptive to a wafer along a scribe line formed on the wafer. Thereby forming a laser processing groove along which the mechanical processing device is used for mechanically breaking the device Cut off.

The laser processing apparatus for performing the above laser processing comprises: a chuck table having a holding surface capable of holding a workpiece; and a laser beam irradiation device for irradiating the laser beam to the chuck table to be processed. Object. Further, the laser light illuminating device comprises: a laser ray oscillator for oscillating the laser beam; and an optical transmission device for transmitting the laser ray oscillated by the laser ray oscillator; the concentrator is The laser light transmitted by the optical transmission device is condensed and irradiated to the workpiece held by the chuck table; and the calibration device is used to detect the area where the laser light should be irradiated.

Advanced technical literature Patent literature

Patent Document 1: Japanese Invention Publication No. 2005-138143

Invention

However, the laser beam oscillated from the laser beam illuminating device constituting the laser processing apparatus and oscillating the laser beam, the irradiation position is slightly rounded as time passes. Deviation. Therefore, even if the region where the laser beam should be irradiated is appropriately detected by the calibration device, there is a problem that the laser beam cannot be appropriately irradiated to the region where the laser beam should be irradiated.

The present invention is based on the above facts, the main technical lessons The problem is to provide a laser processing apparatus having a function of correcting the deviation of the position of the laser beam oscillated by the laser ray oscillator.

In order to solve the above-mentioned main technical problems, according to the present invention, there is provided a laser processing apparatus comprising: a chuck table for holding a workpiece; and a laser beam irradiation device for irradiating the laser beam to the clip The workpiece of the headstock; and the processing feed device, wherein the chuck table is moved relative to the laser beam irradiation device in the machining feed direction (X-axis direction), and the laser processing device The laser light illuminating device comprises: a laser ray oscillator for oscillating a laser beam; and a concentrator having a condensing lens for oscillating the laser by the laser ray oscillator The light is concentrated and irradiated to the workpiece held by the chuck table; the optical path adjusting device is disposed between the laser beam oscillator and the concentrator, and the laser light can be adjusted by the laser beam The optical path of the laser beam oscillated by the oscillator; the mirror is such that the laser beam whose optical path is adjusted by the optical path adjusting device is reflected to the concentrator; the detecting condensing lens is slightly Detecting light concentrating through the mirror a photographing device for photographing a spotlight of the detected light collected by the detecting light collecting lens; and a control mechanism for determining a spotlight of the detecting light captured by the photographing device with respect to The amount of deviation and the direction of the appropriate position are controlled according to the amount and direction of the deviation, so that the light collecting point of the detected light collected by the detecting light collecting lens is positioned at an appropriate position.

A light reduction device should be disposed between the detection light collecting lens and the photographing device.

Further, it is preferable that the focal length of the condensing lens of the concentrator and the focal length of the detecting light condensing lens are set to be the same distance.

In the laser processing apparatus of the present invention, the laser light illuminating device comprises: a laser ray oscillator for oscillating the laser beam; and a concentrator having a condensing lens for oscillating by the laser beam. The laser light oscillated by the device is condensed and irradiated to the workpiece held by the chuck table; the optical path adjusting device is disposed between the laser ray oscillator and the concentrator, and is adjustable The optical path of the laser beam oscillated by the laser ray oscillator; the mirror is such that the laser beam adjusted by the optical path adjusting device adjusts the optical path to the concentrator; The light lens is a light concentrating light that is slightly transmitted through the mirror; the photographing device is a person who photographs the light collected by the light condensing lens; and the control mechanism Controlling, by the amount of deviation and direction of the condensed spot of the detected light taken by the photographing device with respect to the appropriate position, controlling the optical path adjusting device according to the amount of deviation and the direction, so that the condensing lens is condensed by the detecting light Detecting the spotlight of the light is positioned appropriately Therefore, when the condensing point of the detecting light photographed by the photographing device is deviated from the appropriate position, the optical path adjusting device can be controlled to position the condensing point of the detecting light in an appropriate position, so that According to the correction, the laser beam irradiated by the collecting lens and irradiated onto the workpiece held by the chuck holding surface can be irradiated to an appropriate position perpendicular to the holding surface on the upper surface of the chuck table.

Simple illustration

Figure 1 is a perspective view of a laser processing apparatus constructed in accordance with the present invention. Figure.

Fig. 2 is a block diagram showing the arrangement of a laser beam irradiation apparatus equipped with the laser processing apparatus shown in Fig. 1.

3(a) and 3(b) are a side view and a plan view showing another embodiment of the optical path adjusting device constituting the laser beam irradiation apparatus shown in Fig. 2.

Fig. 4 is an explanatory diagram of a photographing signal taken by a photographing apparatus constituting the laser beam irradiation apparatus shown in Fig. 2.

Form for implementing the invention

Hereinafter, preferred embodiments of the laser processing apparatus of the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view showing a laser processing apparatus for carrying out the laser light output setting method of the present invention. The laser processing apparatus 1 shown in Fig. 1 includes a stationary base 2, and a collet table device 3 that is movable to a stationary basis in a machining feed direction (X-axis direction) indicated by an arrow X. The table 2 is held by the workpiece; the laser beam irradiation unit supporting mechanism 4 is movable in an index feeding direction (Y-axis direction) indicated by an arrow Y orthogonal to the X-axis direction. The laser beam irradiation unit 5 and the laser beam irradiation unit 5 are arranged to be disposed on the laser beam irradiation unit support mechanism 4 in the direction of the spot position adjustment (Z-axis direction) indicated by the arrow Z. By.

The chuck mechanism 3 includes a pair of guide rails 31 and 31 which are disposed in parallel with the stationary base 2 along the X-axis direction, and the first slider 32 is movable in the X-axis direction. On the guide rails 31, 31; the second slider 33 is movable in the indexing feed direction indicated by the arrow Y. The first sliding block 32 is provided on the first sliding block 32; the covering base 35 is supported by the second sliding block 33 by the cylindrical member 34; and the chucking table 36 is used as a workpiece holding device. The chuck table 36 is provided with an adsorption chuck 361 formed of a porous material, and the upper surface (holding surface) of the suction chuck 361 is held by a suction device (not shown), for example, in the form of a disk. Semiconductor wafers. The chuck table 36 configured as described above is rotated by a pulse motor (not shown) disposed in the cylindrical member 34. Further, a clamp 362 for fixing an annular frame to be described later is disposed on the chuck table 36.

The first slider 32 is provided on the lower surface thereof with a pair of guided grooves 321 and 321 which are fitted to the pair of guide rails 31 and 31, and a pair of guide rails formed in parallel along the Y-axis direction are provided thereon. 322, 322. The first slide block 32 configured as described above is configured to be movable in the X-axis direction along the pair of guide rails 31 and 31 by the guide grooves 321 and 321 being fitted to the pair of guide rails 31 and 31. The chuck stage mechanism 3 in the illustrated embodiment includes a machining feed device 37 for moving the first slider 32 along the pair of guide rails 31 and 31 in the X-axis direction. The machining feed device 37 includes a male screw group 371 disposed in parallel between the pair of guide rails 31 and 31, and a drive source such as a pulse motor 372 for rotationally driving the male screw group 371. The male thread set 371 has one end rotatably supported by a bearing block 373 fixed to the stationary base 2, and the other end of which is coupled to an output shaft of the pulse motor 372. Further, the male screw group 371 is screwed into a through female screw hole formed in a female screw block (not shown), and the female screw block is protruded from the lower surface of the central portion of the first slide block 32. Therefore, by rotating the male screw group 371 forward and reverse by the pulse motor 372, the first slider 32 can be moved along the guide rails 31, 31 in the X-axis direction.

The second sliding block 33 is provided on the lower surface thereof and is provided on the first The pair of guided grooves 331 and 331 in which the pair of guide rails 322 and 322 on the upper surface of the slider 32 are fitted are fitted to the pair of guide rails 322 and 322 by the guide grooves 331 and 331. It can be moved in the indexing feed direction indicated by arrow Y. The chuck stage mechanism 3 in the illustrated embodiment is provided with a first index feed for moving the second slider 33 along the one of the first sliders 32 to the guide rails 322 and 322 in the Y-axis direction. Device 38. The first indexing feed device 38 includes a male screw group 381 disposed in parallel between the pair of guide rails 322 and 322, and a drive source such as a pulse motor 382 for rotationally driving the male screw group 381. The male screw group 381 is rotatably supported at one end by a bearing block 383 fixed to the upper surface of the first slider 32, and the other end is coupled to an output shaft of the pulse motor 382. Further, the male screw group 381 is screwed into a through female screw hole formed in a female screw block (not shown), and the female screw block is protruded from the lower surface of the central portion of the second slide block 33. Therefore, by rotating the male screw group 381 forward and reverse by the pulse motor 382, the second slider 33 can be moved along the guide rails 322 and 322 in the Y-axis direction.

The above-described laser beam irradiation unit support mechanism 4 is provided with: a pair of guide rails 41 and 41 arranged in parallel along the indexing feed direction indicated by the arrow Y on the base 2, and movable support disposed on the guide rails 41 and 41 in the Y-axis direction Abutment 42. The movable support base 42 is composed of a movement support portion 421 movably disposed on the guide rails 41, 41, and a mounting portion 422 attached to the movement support portion 421. The mounting portion 422 is provided with a pair of guide rails 423, 423 extending in the Z-axis direction in parallel on one side. The laser beam irradiation unit support mechanism 4 in the illustrated embodiment is provided to enable movable support The base 42 moves along the pair of guide rails 41, 41 in the second index feeding device 43 in the Y-axis direction. The second indexing feed device 43 includes a male screw group 431 disposed in parallel between the pair of guide rails 41 and 41, and a drive source such as a pulse motor 432 for rotationally driving the male screw group 431. The male screw group 431 is rotatably supported at one end by a bearing block (not shown) fixed to the stationary base 2, and the other end is coupled to an output shaft of the pulse motor 432. Further, the male screw group 431 is screwed into a female screw hole formed in a female screw block (not shown), and the female screw block is protruded from the lower surface of the center portion of the movement support portion 421 constituting the movable support base 42. Therefore, by rotating the male screw group 431 forward and reverse by the pulse motor 432, the movable support base 42 can be moved along the guide rails 41, 41 in the Y-axis direction.

The illustrated laser beam irradiation unit 5 is provided with a unit support device 51. And a laser light irradiation device 6 mounted on the unit support device 51. The unit support member 51 is provided with a pair of guided grooves 511 and 511 slidably fitted to the pair of guide rails 423 and 423 provided in the mounting portion 422, and the guided grooves 511 and 511 are fitted to the above-mentioned guide grooves 511 and 511. The guide rails 423, 423 are supported to be movable in the Z-axis direction.

The illustrated laser beam irradiation unit 5 is provided to make the unit branch The holding point 51 moves along the Z-axis direction to the condensed spot position adjusting device 53 of the pair of guide rails 423, 423. The condensing point position adjusting device 53 includes a male screw group (not shown) disposed between the pair of guide rails 423 and 423, and a driving source such as a pulse motor 532 for rotationally driving the male screw group, by pulse The motor 532 drives the male screw group (not shown) to rotate forward and reverse, and moves the unit support 51 and the laser beam irradiation device 6 along the guide rails 423 and 423 in the Z-axis direction. In addition, In the embodiment shown in the figure, by rotating the pulse motor 532 forwardly, the laser beam irradiation device 6 is moved upward, and the pulse motor 532 is driven in reverse to move the laser beam irradiation device 6 downward.

The illustrated laser beam illumination device 6 includes a fixed to the above single The cylindrical support case 61 having a member 51 and extending substantially horizontally is supported. This laser light irradiation device 6 will be described with reference to Fig. 2 .

The illustrated laser beam irradiation device 6 is provided with a pulsed laser beam ray oscillating device 62 disposed in the casing 61, and a concentrator 63 having a condensing lens 631 capable of using the pulse ray The pulsed laser light oscillated by the light ray oscillating device 62 is condensed and irradiated onto the workpiece W held on the holding surface of the chuck table 36. The pulsed laser ray oscillating device 62 is composed of a pulsed laser ray oscillator 621 which is an oscillating pulse laser ray LB, and a repetition frequency setting device 622 which is set to oscillate by the pulsed laser ray oscillator 621. The repetition frequency of the pulsed laser light. The concentrator 63 has a condensing lens 631 having a focal length (f1) and is attached to the front end of the casing 61 as shown in FIG.

The illustrated laser beam irradiation device 6 is provided with: a direction changing mirror 64, is disposed between the pulsed laser ray oscillating device 62 and the concentrator 63, and changes the direction of the pulsed laser ray oscillated by the laser ray oscillating device 62; the optical path adjusting device 65 The optical path of the pulsed laser light whose direction is changed by the direction changing mirror 64 is adjusted; the mirror 66 is such that the pulsed laser light of the optical path adjusted by the optical path adjusting device 65 is reflected toward the concentrator 63. The detecting light collecting lens 67 is configured to slightly illuminate the detecting light LBa of the mirror 66 (about 1%); the light reducing device 68 will borrow The detecting light condensed by the detecting light collecting lens 67 is light-reducing; the photographing device 69 is for capturing the light-collecting point of the detecting light dimmed by the light-reducing device 68; and the control device 7.

The optical path adjusting device 65 described above is in the illustrated embodiment. The scanning mirror formed by a Galvano Scanner is controlled by a control device to be described later, and the pulsed laser beam whose direction is changed by the direction changing mirror 64 is swung in the X-axis direction and the Y-axis direction. Adjust the optical path. Here, another embodiment of the optical path adjusting device 65 will be described with reference to FIGS. 3(a) and 3(b). The optical path adjusting device 650 shown in FIGS. 3(a) and (b) is composed of the following members: a rectangular supporting base 651; a mirror 653 supported by the supporting base 651 with a fulcrum 652; and 2 The piezoelectric element 654 is disposed diagonally between the support base 651 and the mirror 653, and varies in amplitude depending on the applied voltage. In the illustrated embodiment, the piezoelectric element 654 has one surface fixed to the support base 651 and the other surface fixed to the mirror 653. Therefore, by controlling the voltage value applied to the piezoelectric element 654, the mounting angle of the mirror 653 can be changed, and the optical path of the pulsed laser light in the direction in which the direction changing mirror 64 is switched can be adjusted.

In the illustrated embodiment, the mirror 66 is made by optical path The adjusting device 65 adjusts 99% of the pulsed laser light of the optical path toward the concentrator 63, and transmits about 1%.

Detection of condensed light passing through the mirror 66 The light condensing lens 67 is set to (f1) like the condensing lens 631 of the concentrator 63 described above. The dimming device 68 that diffracts the detection light collected by the detection light collecting lens 67 is constructed by an ND filter in the illustrated form. to make. Further, the imaging device 69 is constituted by a CCD camera and is positioned at a position of the focal length (f1) of the detection light collecting lens 67. The control device 7 determines the amount and direction of deviation of the condensed point of the detected ray captured by the imaging device 69 with respect to the appropriate position, and controls the optical path adjusting device 65 to modulate the detected light according to the amount and direction of the deviation. The condensed spot of the detected light collected by the optical lens 67 is positioned at an appropriate position.

Returning to Figure 1, the illustrated laser processing apparatus has a calibration. The quasi-equipment 8, which is disposed at the front end of the casing 61 and photographs a processing area to be subjected to laser processing by the above-described laser beam irradiation apparatus 6. The calibration device 8 is constituted by an optical device such as a microscope or a CCD camera, and sends the captured image signal to the control device 7.

The laser processing apparatus in the embodiment shown in the figure is as above The pulsed laser beam oscillated by the pulsed laser ray oscillating device 62 and condensed by the concentrator 63 must be perpendicular to the holding surface on the upper surface of the chuck table 36. However, the laser light oscillated by the pulsed laser ray oscillating device 62 will slightly deviate from the optical path over time, and the illumination position will deviate slightly from the appropriate position. Therefore, the deviation must be corrected.

Hereinafter, mainly referring to FIG. 2, the correction is made by pulsed laser light. A method of shifting the optical path of the laser beam oscillated by the oscillating device 62.

The laser beam LB oscillated by the pulsed laser ray oscillator 621 of the pulsed laser ray oscillating device 62 is guided to the concentrator 63 through the direction changing mirror 64, the optical path adjusting device 65, and the mirror 66, and The condensing lens 631 collects light and irradiates the workpiece W held on the holding surface of the chuck table 36. On the other hand, a portion of the detection light ray LBa transmitted through the mirror 66 is condensed by the detection light condensing lens 67, and is dimmed by the dimming device 68 to reach the imaging device 69. As shown in FIG. 4, the photographing device 69 takes a spot S of the detection light ray LBa and sends the photographing signal to the control device 7. The control device 7 obtains the X-axis direction deviation amount Δx and the Y-axis direction deviation of the light-converging point S with respect to the appropriate position 0 as shown in FIG. 4, based on the image pickup signal shown in FIG. 4 transmitted from the image pickup device 69. The amount Δy (the deviation amount detecting step). In this way, when the X-axis direction deviation amount Δx and the Y-axis direction deviation amount Δy of the detection spot ray LBa with respect to the appropriate position 0 are obtained, the control device 7 determines the condensed point S with respect to X. The inclination angle of the shaft (α) and the inclination angle (β) of the condensed point S with respect to the Y-axis. That is, if the distance from the optical path adjusting device 65 to the imaging device 69 is L, sin α = Δx / L, α = sin ^-1 (Δx / L). Further, if the distance from the optical path adjusting device 65 to the imaging device 69 is L, sin β = Δy / L, β = sin ^-1 (Δy / L). Thus, when the inclination angle (α) of the focused spot S with respect to the X axis and the inclination angle (β) of the focused spot S with respect to the Y axis are obtained, the amount of deviation Δx and the Y-axis direction of the control device 7 according to the X-axis direction is obtained. The deviation amount Δy, and the inclination angle (α) with respect to the X axis and the inclination angle (β) with respect to the Y axis, control the optical path adjusting device 65 to position the condensed spot S at an appropriate position 0. As a result, the optical path of the pulsed laser LB oscillated by the pulsed laser ray oscillator 621 of the pulsed laser ray oscillating device 62 is corrected by the optical path adjusting device 65, and the illuminating light of the detecting light LBa transmitted through the mirror 66 is condensed. Point S will be positioned at the appropriate position 0 (optical path correction step). By correcting the optical path as described above, the transmission mirror 66 is guided to the condenser 63, and condensed by the condensing lens 631 to illuminate the pulsed laser beam of the workpiece W held on the holding surface of the chuck table 36. It will be perpendicular to the holding surface on the upper surface of the chuck table 36 and irradiated in place. Therefore, the pulsed laser light can be appropriately irradiated to the processing area which is detected by the calibration device 8 and which should be subjected to laser processing by the laser beam irradiation device 6. Further, in the illustrated embodiment, since the focal length (f1) of the detecting light collecting lens 67 and the focal length (f1) of the collecting lens 631 of the concentrator 63 are set to the same distance, the light ray of the detecting light LBa is detected. The point S is substantially the same as the spot position of the pulsed laser beam irradiated to the workpiece W held by the holding surface of the chuck table 36 by the condensing lens 631, and is substantially the same as the chuck. The retaining surface above the table 36 is in a vertical position for proper positioning. Further, in the illustrated form, since a portion of the detection light LBa transmitted through the mirror 66 is condensed by the detection light collecting lens 67 and is dimmed by the dimming device 68 to reach the photographing device 69, The photographing device 69 is damaged.

1‧‧‧ Laser processing equipment

2‧‧‧Standing abutment

3‧‧‧chate table mechanism

4‧‧‧Laser light irradiation unit support mechanism

5‧‧‧Laser light irradiation unit

6‧‧‧Laser light irradiation equipment

7‧‧‧Control equipment

8‧‧‧ calibration equipment

31‧‧‧ Guide track

32‧‧‧1st sliding block

33‧‧‧2nd sliding block

34‧‧‧Cylinder components

35‧‧‧ Coverage

36‧‧‧ chuck table

37‧‧‧Processing feed equipment

38‧‧‧1st indexing equipment

41‧‧‧ Guide track

42‧‧‧ movable support abutment

43‧‧‧2nd indexing feeding device

51‧‧‧Unit support

53‧‧‧ Spot position adjustment equipment

61‧‧‧Shell

62‧‧‧Pulse laser ray oscillating equipment

63‧‧‧ concentrator

64‧‧‧ Directional change mirror

65, 650‧ ‧ optical path adjustment equipment

66‧‧‧Mirror

67‧‧‧Detection concentrating lens

68‧‧‧Light reduction equipment

69‧‧‧Photographing equipment

321‧‧‧Guided ditch

322‧‧‧Guidance track

331‧‧‧Guided ditch

361‧‧‧Adsorption chuck

362‧‧‧ fixture

371‧‧‧Male thread set

372‧‧‧pulse motor

373‧‧‧ bearing block

381‧‧‧A male thread set

382‧‧‧pulse motor

383‧‧‧ bearing block

421‧‧‧Mobile Support Department

422‧‧‧Installation Department

423‧‧‧ Guide rail

431‧‧‧A male thread set

432‧‧‧pulse motor

511‧‧‧guided ditch

532‧‧‧pulse motor

621‧‧‧pulse laser ray oscillator

622‧‧‧Repetition frequency setting device

631‧‧‧ Concentrating lens

LB‧‧‧pulse laser light

LBa‧‧‧Detecting light

S‧‧‧ spotlight

W‧‧‧Processed objects

X, Y, Z‧‧‧ arrows

1 is a perspective view of a laser processing apparatus constructed in accordance with the present invention.

Fig. 2 is a block diagram showing the arrangement of a laser beam irradiation apparatus equipped with the laser processing apparatus shown in Fig. 1.

3(a) and 3(b) are a side view and a plan view showing another embodiment of the optical path adjusting device constituting the laser beam irradiation apparatus shown in Fig. 2.

Fig. 4 is an explanatory diagram of a photographing signal taken by a photographing apparatus constituting the laser beam irradiation apparatus shown in Fig. 2.

7‧‧‧Control equipment

36‧‧‧ chuck table

62‧‧‧Pulse laser ray oscillating equipment

63‧‧‧ concentrator

64‧‧‧ Directional change mirror

65‧‧‧Light path adjustment equipment

66‧‧‧Mirror

67‧‧‧Detection concentrating lens

68‧‧‧Light reduction equipment

69‧‧‧Photographing equipment

621‧‧‧pulse laser ray oscillator

622‧‧‧Repetition frequency setting device

631‧‧‧ Concentrating lens

LB‧‧‧pulse laser light

LBa‧‧‧Detecting light

W‧‧‧Processed objects

Claims (3)

A laser processing apparatus comprising: a chuck table for holding a workpiece; a laser beam irradiation device for irradiating laser light to a workpiece held by the chuck table; and a processing feed device And moving the chuck table relative to the laser beam irradiation device in a machining feed direction (X-axis direction), wherein the laser processing device is characterized in that: the laser beam irradiation device includes: a ray ray oscillator for oscillating a laser beam; a concentrator having a condensing lens for concentrating the laser beam oscillated by the laser ray oscillator and illuminating and holding the gantry The object to be processed; the optical path adjusting device is disposed between the laser beam oscillator and the concentrator, and can adjust the optical path of the laser beam oscillated by the laser ray oscillator; a mirror for reflecting a laser beam whose optical path is adjusted by the optical path adjusting device is reflected to the concentrator; and detecting a condensing lens for illuminating the light through the mirror; the photographing device , the filming is gathered by the detection light collecting lens And a control unit for determining a deviation amount and a direction of a condensed spot of the detected ray detected by the photographing device with respect to an appropriate position, and controlling the amount according to the amount and direction of the deviation The optical path adjusting device positions the condensed spot of the detected light collected by the detecting light collecting lens in an appropriate position By. The laser processing apparatus of claim 1, wherein the detecting light collecting lens and the photographing apparatus are provided with a light reducing device. The laser processing apparatus according to claim 1 or 2, wherein a focal length of the condensing lens of the concentrator and a focal length of the detecting condensing lens are set at the same distance.