TW201601233A - Laser machining device - Google Patents

Abstract

The object of the present invention is to provide a laser machining device capable of preventing a cross section of a groove from being in a V-shape and allowing an angle between a side wall and a bottom wall of the groove to be a right angle. The solution relates to a laser machining device which includes a workpiece holding means for holding a workpiece, a laser beam irradiation means for irradiating the workpiece held on the workpiece holding means with laser beams, an X-axis direction feeding means for allowing the workpiece holding means and the laser beam irradiation means to move relatively along a machining feeding direction (X-axis direction), and a Y-axis direction feeding means for allowing the workpiece holding means and the laser beam irradiation means to be fed for machining along a Y-axis direction perpendicular to the X-axis direction. Wherein, the laser beam irradiation means has a laser beam oscillation means for generating a laser beam through oscillation, a condenser lens for condensing the laser beam generated through oscillation by the laser beam oscillation means and irradiating the workpiece held on a chuck table with the laser beam, and an optical axis inclining means arranged between the laser beam oscillation means and the condenser lens for enabling an optical axis of the laser beam to be eccentric in relation to a central axis of the condenser lens and inclining the optical axis of the laser in relation to the central axis of the condenser lens.

Description

Laser processing device Field of invention

The present invention relates to a laser processing apparatus that applies laser processing to a workpiece such as a semiconductor wafer.

Background of the invention

In the manufacturing process of the semiconductor device, a plurality of regions are divided by a predetermined dividing line arranged in a lattice shape on the surface of the substantially disk-shaped semiconductor wafer, and ICs, LSIs, and the like are formed in the divided regions. Device. Further, by cutting the semiconductor wafer along the dividing line, the region in which the device is formed is divided to manufacture a single device.

As a method of dividing the semiconductor wafer by dividing the predetermined semiconductor line along the dividing line, there has been an ablation process by irradiating a pulsed laser beam having a wavelength that is absorptive to the wafer along a dividing line to form a laser processing groove. And the method of breaking along this laser processing groove was proposed.

The laser processing apparatus for performing laser processing includes a workpiece holding means for holding a workpiece, and a laser beam irradiation means for irradiating the workpiece to be held by the workpiece holding means a processing feeding means for moving the workpiece holding means and the laser beam irradiation means relatively in the processing feed direction, and the workpiece holding means and The indexing means for moving the laser beam irradiation means relatively in the indexing feed direction orthogonal to the machining feed direction (see, for example, Patent Document 1).

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2006-253432

Summary of invention

However, when the laser beam is irradiated to the workpiece to form a laser processing groove, the cross section of the groove is V-shaped, and the processing cannot be continued.

Further, since the groove width cannot be uniformly formed from the incident side of the laser beam toward the groove bottom, there is a problem that the boundary between the side wall of the groove and the bottom wall does not form a right angle when the groove is formed.

The present invention has been made in view of the above circumstances, and a main technical object thereof is to provide a laser processing apparatus which can form a cross-section of a groove and a V-shape, and can form a right angle between an edge of a groove and a bottom wall.

In order to solve the above-mentioned main technical problems, the laser processing apparatus according to the present invention includes a workpiece holding means for holding a workpiece, and irradiates the workpiece to be held by the workpiece holding means with laser light. The laser beam irradiation means, the X-axis direction feeding means for relatively moving the workpiece holding means and the laser beam irradiation means in the machining feed direction (X-axis direction), and the workpiece holding means and the laser Light exposure a Y-axis direction feeding means for processing a feed in a Y-axis direction orthogonal to the X-axis direction, the laser processing apparatus characterized in that the laser beam irradiation means is provided with a laser beam oscillating means for oscillating to generate a laser beam And a collecting lens that illuminates the laser beam generated by the oscillation of the laser beam oscillating means to illuminate the workpiece held on the working table, and the laser beam oscillating means and the concentrating light The optical axis between the lenses is such that the optical axis of the laser beam is eccentric with respect to the central axis of the condensing mirror, and the optical axis of the laser beam is tilted with respect to the central axis of the condensing lens on the condensing side.

The optical axis tilting means is constituted by a Y-axis direction tilting unit for causing an optical axis of a laser beam oscillated from a laser beam oscillating means to be opposite to a central axis of the collecting lens at Y Move in the direction of the axis.

Further, the optical axis tilting means is constituted by a Y-axis direction tilting unit and an X-axis direction scanning unit for causing an optical axis of the laser beam oscillated from the laser beam oscillating means to be relative to the optical axis The central axis of the collecting lens moves in the X-axis direction.

In the laser processing apparatus of the present invention, the laser beam irradiation means is provided with a laser beam oscillating means for oscillating the laser beam, and the laser beam generated by the oscillation of the laser beam oscillating means is collected and held by a condensing lens that irradiates the workpiece on the working table, and is disposed between the laser beam illuminating means and the condensing lens to eccentrically align the optical axis of the laser beam with respect to a central axis of the condensing lens, and Converging side makes laser light The optical axis tilting means with respect to the central axis of the collecting lens, so that when the laser processing groove is to be formed in the X-axis direction, the optical axis of the laser light is processed relative to the laser to be formed The groove edge is formed by obliquely oscillating and oscillating in the Y-axis direction to form a laser processing groove which is parallel from the incident side of the laser beam toward the bottom wall.

Further, when the laser processing groove formed on the workpiece is formed (because the groove width cannot be uniformly formed from the incident side of the laser beam toward the bottom of the groove, the boundary between the side wall of the groove and the bottom wall is formed when the groove is formed. When the correction processing is performed, the side walls and the bottom wall of the laser processing groove can be irradiated by illuminating the optical axis of the laser light to illuminate the boundary between the side wall and the bottom wall forming the groove. The junction is formed at a substantially right angle.

2‧‧‧Standing abutment

3‧‧‧Working table mechanism

31, 322‧‧‧ rails

32‧‧‧1st slider

321,331‧‧‧guided ditch

33‧‧‧2nd slider

34‧‧‧Cylinder components

35‧‧‧Support table

36‧‧‧Working table

361‧‧‧Adsorption chuck

362‧‧‧ fixture

37‧‧‧X-axis feed means

371, 381‧‧‧ male screw

372, 382‧‧ ‧ pulse motor

38‧‧‧Y-axis feed means

383‧‧‧ bearing block

4‧‧‧Laser light irradiation unit

41‧‧‧Support members

42‧‧‧shells

5‧‧‧Laser light exposure

51‧‧‧Laser light oscillation

511‧‧‧YAG laser oscillator

512‧‧‧Repetition frequency setting means

52‧‧‧ Concentrating lens

520‧‧‧ concentrator

53‧‧‧ Optical axis tilting means

54‧‧‧Y-axis tilt unit

541‧‧‧1st galvanometer scanner

541a‧‧‧1st mirror

541b, 542b, 552b‧‧‧ Angle adjustment actuator

542‧‧‧2nd galvanometer scanner

542a‧‧‧2nd mirror

543‧‧‧ optical axis changing mirror

55‧‧‧X-axis direction scanning unit

551‧‧‧ Directional change mirror

552‧‧‧3rd galvanometer scanner

552a‧‧‧3rd mirror

6‧‧‧Photography

8‧‧‧Control means

81‧‧‧ central processing unit

82‧‧‧Read-only memory

83‧‧‧ Random access memory

84‧‧‧Input interface

85‧‧‧Output interface

10‧‧‧矽 substrate

101‧‧‧Processing line

110, 120‧‧ ‧ laser processing ditch

110a, 120a‧‧‧ bottom wall

110b, 110c, 120b, 120c‧‧‧ side walls

F‧‧‧Ring frame

P1, P2, P3, Pa, Pb, Pc‧‧‧ spotlights

T‧‧‧Protection tape

W‧‧‧Processed objects

X, Y, X1‧‧‧ arrows

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a laser processing apparatus constructed in accordance with the present invention.

Figure 2 is a block diagram showing the arrangement of laser light irradiation means provided on the laser processing apparatus shown in Figure 1.

Fig. 3 is a block diagram showing another embodiment of the laser beam irradiation means shown in Fig. 2.

Fig. 4 is a block diagram showing the configuration of an X-axis direction scanning unit equipped with the laser beam irradiation means shown in Fig. 2.

Figure 5 is a block diagram showing the control means of the laser processing apparatus shown in Figure 1.

Fig. 6 is a perspective view showing a state in which a ruthenium substrate as a workpiece is adhered to a surface of a dicing tape attached to an annular frame.

(a) to (c) of FIG. 7 are explanatory views of a laser processing groove forming step performed on a crucible substrate as a workpiece using the laser processing apparatus shown in FIG. 1.

Fig. 8 is a cross-sectional view showing a laser processing groove formed by a conventional laser processing.

9(a) to 9(c) are explanatory views of a laser processing groove correction step performed by using the laser processing apparatus shown in Fig. 1.

Form for implementing the invention

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

Figure 1 shows a laser processing apparatus constructed in accordance with the present invention. Stereogram. The laser processing apparatus shown in Fig. 1 is provided with a stationary base 2, which is arranged to be movable on the stationary base 2 in a machining feed direction (X-axis direction) indicated by an arrow X and used for holding a workpiece. The working chuck mechanism 3 and the laser light irradiation unit 4 disposed on the base 2 as a laser beam irradiation means.

The above-described work clamping mechanism 3 includes a pair of guide rails 31 and 31 which are arranged in parallel along the X-axis direction on the stationary base 2, and a first slider which is disposed to be movable in the X-axis direction on the guide rails 31 and 31. 32. The second slider 33 that is movable in the machining feed direction (Y-axis direction) indicated by the arrow Y orthogonal to the X-axis direction on the first slider 32, and the cylindrical member 34 The support table 35 supported by the second slider 33 and the work chuck 36 as a workpiece holding means. The working chuck 36 is provided with an adsorption chuck 361 formed of a porous material, and is formed to be capable of being taken by a suction means not shown. The wafer-like semiconductor wafer of the workpiece is held on the holding surface which is the upper surface of the chuck 13 to be chucked. The working chuck 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 that supports a workpiece such as a semiconductor wafer through a protective tape is disposed on the work chuck 36.

The first slider 32 is provided with a pair of guided grooves 321 and 321 fitted to the pair of guide rails 31 and 31 on the lower surface thereof, and is formed on the upper surface thereof in parallel along the Y-axis direction. A pair of guide rails 322, 322. The first slider 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 fitting the guided grooves 321 and 321 to the pair of guide rails 31 and 31. The work clamping mechanism 3 in the illustrated embodiment includes an X-axis direction feeding means 37 for moving the first slider 32 along the pair of rails 31, 31 in the X-axis direction. The X-axis direction feeding means 37 includes a male screw 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 371. The male screw 371 is rotatably supported at one end by a bearing block 373 fixed to the stationary base 2, and the other end thereof is driven and coupled by an output shaft of the pulse motor 372. Further, the male screw 371 is screwed into the through screw hole formed in the female nut which is not shown and which is provided on the lower surface of the central portion of the first slider 32. Therefore, the first slider block 32 can be moved in the X-axis direction along the guide rails 31 and 31 by the forward rotation of the pulse motor 372 and the reverse rotation of the male screw 371.

The second slider 33 is provided on the lower surface thereof with a pair of guided grooves 331 and 331 which are engageable with a pair of guide rails 322 and 322 provided on the upper surface of the first slider 32, and The guided grooves 331 and 331 are fitted to one The guide rails 322 and 322 are configured to be movable in the Y-axis direction. The work clamping mechanism 3 in the illustrated embodiment is provided with a Y-axis direction for moving the second slider 33 along the pair of guide rails 322 and 322 provided on the first slider 32 in the Y-axis direction. Means 38. The Y-axis direction feeding means 38 includes a male screw 381 which is disposed in parallel between the pair of guide rails 322 and 322, and a drive source for a pulse motor 382 or the like for rotationally driving the male screw 381. The male screw 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 thereof is coupled to the output shaft of the pulse motor 382. Further, the male screw 381 is screwed into a through screw hole formed in a female nut (not shown) which is protruded from the lower surface of the central portion of the second slider 33. Therefore, the second slider 33 can be moved in the Y-axis direction along the guide rails 322 and 322 by the forward rotation of the pulse motor 382 and the reverse rotation of the male screw 381.

The laser beam irradiation unit 4 includes a support member 41 disposed on the stationary base 2, a casing 42 supported by the support member 41 and extending substantially horizontally, and laser light disposed on the casing 42. The means 5 and the imaging means 6 disposed at the front end portion of the casing 42 and capable of detecting the processing area for laser processing. Further, in the embodiment shown in the drawing, in addition to the general imaging element (CCD) that images by visible light, the imaging means 6 can capture the infrared illumination by means of an infrared illumination means that can irradiate the workpiece with infrared rays. An optical system for infrared rays to be irradiated by the means, and an imaging element (infrared CCD) capable of outputting an electrical signal corresponding to infrared rays captured by the optical system, and the captured image signal can be transmitted to a control to be described later. means.

The above-described laser beam irradiation means 5 will be described with reference to Fig. 2 .

The laser beam irradiation means 5 includes a pulsed laser beam oscillating means 51 for oscillating the pulsed laser beam, and a pulsed laser beam oscillated by the pulsed laser ray oscillating means 51 for concentrating and holding the laser beam a concentrator 520 of the condensing lens 52 that irradiates the workpiece W on the gantry 36, and a ray concentrating lens 51 and a condensing lens 52 disposed between the pulsed laser beam illuminating means 51 and the condensing lens 52. The central axis of the optical lens 52 is eccentric, and the optical axis tilting means 53 for tilting the optical axis of the laser beam with respect to the central axis of the collecting lens 52 on the collecting side. The pulsed laser beam oscillating means 51 is constituted by a YAG laser oscillator 511 and a repetition frequency setting means 512 attached thereto.

The optical axis tilting means 53 is constituted by a Y-axis direction tilting unit 54 which can cause laser light oscillated from the pulsed laser beam oscillating means 51 in the embodiment shown in FIG. The optical axis moves in the Y-axis direction with respect to the central axis of the collecting lens. The Y-axis direction tilting unit 54 is composed of a first galvano scanner 541, a second galvanometer scanner 542, and an optical axis changing mirror 543. The first galvanometer scanner 541 is composed of a first mirror 541a and an angle adjustment actuator 541b that adjusts an installation angle of the first mirror 541a, and the angle adjustment actuator 541b is controlled by a control means to be described later. . The first galvanometer scanner 541 configured as described above can illuminate the pulsed laser beam oscillated by the pulsed laser ray oscillating means 51 toward the second galvanometer scanner 542. The second galvanometer scanner 542 is composed of a second mirror 542a and an angle adjustment actuator 542b that adjusts the installation angle of the second mirror 542a, and the angle adjustment actuator 542b is rearward. Controlled by the control means described. The second galvanometer scanner 542 configured as described above can reflect the pulsed laser beam oscillated by the pulsed laser beam oscillating means 51 and reflected by the first galvanometer scanner 541 toward the optical axis changing mirror 543. The optical axis changing mirror 543 can illuminate the pulsed laser beam that is oscillated by the pulsed laser beam oscillating means 51 and transmitted through the first galvanometer scanner 541 and the second galvanometer scanner 542 toward the condensing lens 52. Perform direction change. Further, the concentrator 520 including the condensing lens 52 is disposed at the front end portion of the casing 42 as shown in FIG. Further, the concentrator 520 is formed to be movable in the condensed spot position adjustment direction (Z-axis direction) by a condensed spot position adjusting means (not shown).

The Y-axis direction tilting unit 54 of the illustrated embodiment is configured as described above, and the operation thereof will be described below.

The first mirror 541a and the second mirror 542a of the first galvanometer scanner 541 and the second galvanometer scanner 542 are positioned at positions indicated by solid lines in FIG. 2, and pulsed laser rays are used. The pulsed laser beam oscillated by the oscillating means 51 is collected by the optical axis changing mirror 543 and the condensing lens 52 as indicated by a solid line to be collected at the condensing point P1. Further, the first mirror 541a and the second mirror 542a of the first galvanometer scanner 541 and the second galvanometer scanner 542 are rotated in one direction from the solid line position as shown by a broken line in Fig. 2, respectively. In the state of the same angle, the pulsed laser light oscillated by the pulsed laser ray oscillating means 51 passes through the optical axis changing mirror 543 and the condensing lens 52 as indicated by the broken line so that the optical axis is opposite to the center of the condensing lens 52. The axis is inclined to be concentrated to the light collecting point P1. Further, the first mirror 541a and the second mirror 542a of the first galvanometer scanner 541 and the second galvanometer scanner 542 are respectively a two-point chain in FIG. The pulsed laser beam oscillated by the pulsed laser beam oscillating means 51 is transmitted through the optical axis changing mirror 543 as indicated by a 2-point chain line in a state where the line is rotated by the same angle from the solid line position to the other direction. The condensing lens 52 converges the optical axis with respect to the central axis of the condensing lens 52 to be concentrated to the condensing point P1.

On the other hand, the first mirror 541a and the second mirror 542a of the first galvanometer scanner 541 and the second galvanometer scanner 542 are second reflected from the state of FIG. 2 to the second galvanometer scanner 542. When the rotation angle of the mirror 542a is slightly shifted, as shown in FIG. 3, the pulsed laser beam oscillated by the pulsed laser beam oscillating means 51 passes through the optical axis changing mirror 543 and the collecting lens 52 in the state of the broken line. The optical axis is slanted to the condensing point P2 with respect to the central axis of the condensing lens 52, and passes through the optical axis changing mirror 543 and the condensing lens 52 in the state of the two-dot chain line so that the optical axis is opposed to the condensing lens. The central axis of 52 is inclined to be concentrated to the light collecting point P3. By appropriately adjusting the installation angles of the first mirror 541a and the second mirror 542a of the first galvanometer scanner 541 and the second galvanometer scanner 542, the pulsed laser ray oscillating means 51 can be used. The pulsed laser light generated by the oscillation is concentrated at an arbitrary inclination angle in the Y-axis direction to an arbitrary position.

Next, another embodiment of the optical axis tilting means 53 will be described with reference to Fig. 4 .

The optical axis tilting means 53 shown in Fig. 4 is disposed between the Y-axis direction tilting unit 54 and the collecting lens 52 and allows the optical axis of the laser beam generated by the oscillation of the pulsed laser beam oscillating means 51 to be relatively opposed. The X-axis direction scanning unit 55 that moves the central axis of the condensing lens in the X-axis direction is constituted. The X-axis direction scanning unit 55 is changed by the optical axis of the above-described Y-axis direction tilting unit 54. a direction changing mirror 551 for performing direction change in the horizontal direction of the pulsed laser light reflected by the mirror 543, and an optical axis of the pulsed laser light having undergone direction change by the direction changing mirror 551 with respect to the collecting lens The third oscilloscope scanner 552 whose central axis of 52 moves in the X-axis direction is constituted. The third galvanometer scanner 552 is constituted by a third mirror 552a and an angle adjustment actuator 552b that adjusts the installation angle of the third mirror 552a, and the angle adjustment actuator 552b is controlled by a control means to be described later. In the X-axis direction scanning unit 55 configured as described above, the third mirror 552a of the third galvanometer scanner 552 is positioned at a position indicated by a solid line in FIG. 4, and the transmission direction changing mirror 551 can be used. The guided pulsed laser light is collected by the collecting lens 52 as shown by a solid line to the light collecting point Pa. Further, in a state where the third mirror 552a of the third galvanometer scanner 552 is positioned at a position indicated by a broken line in FIG. 4, the pulsed laser beam guided by the transmission direction changing mirror 551 can be guided as a broken line. The condensing lens 52 is concentrated to the condensing point Pb as shown. Further, in a state where the third mirror 552a of the third galvanometer scanner 552 is positioned at a position indicated by a two-dot chain line in FIG. 4, a pulse laser guided by the direction changing mirror 551 can be guided. The light is collected by the condensing lens 52 to the condensing point Pc as indicated by a 2-point chain line. In this manner, the optical axis of the pulsed laser beam oscillated by the pulsed laser beam oscillating means 51 can be made to be in the X-axis direction with respect to the central axis of the collecting lens 52 by controlling the operation of the angle adjusting actuator 552b. Shake.

The laser processing apparatus in the illustrated embodiment is provided with the control means 8 shown in FIG. The control means 8 is composed of a computer, and includes a central processing unit (CPU) 81 for performing calculation processing according to the control program, a read-only memory (ROM) 82 for storing a control program, etc., for storing the calculation result. A readable and writable random access memory (RAM) 83, an input interface 84, and an output interface 85 are provided. A detection signal from the imaging means 6 or the like can be input to the input interface 84 of the control means 8. Further, the control signal can be output from the output interface 85 of the control means 8 to the angles of the X-axis direction feeding means 37, the Y-axis direction feeding means 38, the pulsed laser beam oscillating means 51, and the first galvanometer scanner 541. The actuator 541b, the angle adjustment actuator 542b of the second galvanometer scanner 542, the angle adjustment actuator 552b of the third galvanometer scanner 552, and the like are adjusted.

The laser processing apparatus in the embodiment shown in the drawings is configured as described above, and the operation thereof will be described below.

Fig. 6 is a perspective view showing a substrate as a workpiece. The tantalum substrate 10 shown in Fig. 6 is formed into, for example, a circular shape having a thickness of 200 μm, and a processing line 101 is provided on the surface. The ruthenium substrate 10 is formed by adhering one of the faces to the surface of the protective tape T attached to the annular frame F.

A first embodiment in which laser processing is performed on the ruthenium substrate 10 as the above-described workpiece using the above-described laser processing apparatus will be described.

First, the protective tape T side of the ruthenium substrate 10 is placed on the work chuck 36 of the laser processing apparatus shown in FIG. Then, the crucible substrate 10 is sucked and held by the protective tape T via the protective tape T by the suction means not shown (the workpiece holding step).

As described above, the working chuck 36 that sucks and holds the 矽 substrate 10 is positioned directly below the imaging device 6 through the X-axis direction feeding means 37. In this manner, after the work chuck 36 is positioned directly below the image pickup device 6, the alignment operation for detecting the processing region for the laser processing of the ruthenium substrate 10 can be performed by the image pickup means 6 and the control means 8. . That is, camera The means 6 and the control means 8 perform the alignment of the processing line 101 formed on the crucible substrate 10 and the position of the concentrator 520 constituting the laser beam irradiation means 5 for irradiating the laser beam along the processing line 101. Image processing such as pattern matching to complete calibration of the position of the laser beam.

When the processing line 101 formed on the crucible substrate 10 held on the working chuck 36 is detected as described above and the laser light irradiation position is calibrated, it can be as shown in Fig. 7(a). It is shown that the working chuck 36 is moved to the laser light irradiation area where the concentrator 520 of the laser light irradiation means 5 irradiating the laser light is located, and one end of the predetermined processing line 101 is formed (in FIG. 7(a) The left side is positioned directly below the concentrator 520 of the laser beam illumination means 5. Then, the control means 8 controls the condensed spot position adjusting means not shown, and positions the condensed spot of the pulsed laser ray irradiated from the concentrator 520 to the vicinity of the upper surface of the cymbal substrate 10. Next, the control means 8 controls the pulsed laser beam oscillating means 51 to control the first galvanometer scanner 541 and the second when irradiating the pulsed laser beam having a wavelength which is absorbing from the concentrating substrate 10 from the concentrator 520. The angle adjustment actuator 541b and the angle adjustment actuator 542b of the galvanometer scanner 542 alternately change the first mirror 541a and the second mirror 542a to a dotted line state as shown in FIG. 2 or FIG. In the state of the two-point chain line, while the X-axis direction feeding means 37 is controlled, the work chuck 36 is moved at a predetermined feed speed in the direction indicated by the arrow X1 in Fig. 7 (a) (laser processing groove forming step) ). Therefore, as shown in FIG. 7(c), the laser beam irradiated to the crucible substrate 10 is shaken in the Y-axis direction in such a manner that the optical axis is in a state of a broken line and a state of a two-dot chain line. As a result, the tantalum substrate 10 is formed along the processing line 101 as shown in FIG. 7(c) from the incident side (upper surface) of the laser beam toward The laser processing groove 110 is formed such that the side walls 110b and 110c are parallel to the bottom wall 110a. Further, as shown in FIG. 7(b), when the irradiation position of the concentrator 520 reaches the other end of the processing line 101 (the right end in FIG. 7(b)), the irradiation of the pulsed laser light is stopped and the working clamp is stopped. The movement of the table 36. As a result, as shown in FIG. 7(b), the side walls 110b and 110c are formed parallel to the processing line 101 as shown in FIG. 7(c), and the side walls 110b and 110c are opposed to each other. 110a is a right angle laser processing groove 110.

In the above-described laser processing groove forming step, the third mirror is moved by controlling the operation of the angle adjusting actuator 552b of the third galvanometer scanner 552 constituting the X-axis direction scanning unit 55 shown in FIG. 552a is alternately positioned at a position indicated by a broken line and a position indicated by a 2-point chain line, and the laser beam can be irradiated while the optical axis of the laser beam is oscillated in the X-axis direction with respect to the central axis of the collecting lens 52. Light rays can thus promote the formation of the above-described laser processing grooves 110.

Further, the processing conditions of the above-described laser processing groove forming step are set under the following conditions, for example.

Laser light wavelength: 355nm

Repeat frequency: 50kHz

Average output: 3W

Spot point diameter: φ10μm

Processing feed rate: 100mm / sec

Next, a second embodiment in which laser processing is performed on the crucible substrate 10 as the above-described workpiece using the above-described laser processing apparatus will be described.

As shown in FIG. 8, this second embodiment is a modification processing of the laser processing groove 120 formed on the cymbal substrate 10 along the processing line 101. If general laser processing is performed, as shown in Fig. 8, the side walls 120b, 120c are not formed in parallel, but are tapered, and the boundary between the side walls 120b, 120c and the bottom wall 120a does not form a right angle. In the second embodiment, the side walls 120b and 120c of the laser processing groove 120 are processed as shown by broken lines to correct the boundary between the side walls 120b and 120c and the bottom wall 120a at a right angle.

In order to perform the processing of correcting the boundary between the side walls 120b, 120c and the bottom wall 120a of the laser processing groove 120 formed on the above-described ruthenium substrate 10 at right angles, first, the laser processing groove 120 is formed as shown in FIG. 9(a). The vicinity of the boundary between the side wall 120b and the bottom wall 120a is positioned below the collecting lens 52. Then, the control means 8 controls the condensed spot position adjusting means not shown, and positions the irradiation position of the pulsed laser light irradiated from the concentrator 520 in the laser processing groove as shown in FIG. 9(a). Near the boundary between the side wall 120b of 120 and the bottom wall 120a. Next, the control means 8 controls the pulsed laser beam oscillating means 51 to illuminate the pulsed laser beam having a wavelength which is absorptive to the ruthenium substrate 10 from the concentrator 520, and controls the first galvanometer scanner 541 and the second oscillating light. The angle adjustment actuator 541b and the angle adjustment actuator 542b of the mirror scanner 542 alternately change the first mirror 541a and the second mirror 542a to a dotted line state and 2 as shown in FIG. 2 or FIG. In the state of the dotted line, the X-axis direction feeding means 37 is controlled to move the working chuck 36 at a predetermined feed speed in the X-axis direction (the direction perpendicular to the paper surface in FIG. 9(a)) (1st) Laser processing groove correction step). As a result, the boundary between the side wall 120b of the laser processing groove 120 and the bottom wall 120a is formed to be substantially a right angle as shown in Fig. 9(b).

Next, a process of correcting the boundary between the side wall 120c of the laser processing groove 120 and the bottom wall 120a to a right angle is performed. The control means 8 can control the Y-axis direction feeding means 38 to position the side wall 120c and the bottom wall of the laser processing groove 120 as shown in Fig. 9(b) from the state in which the first laser processing groove correction step has been performed. The vicinity of the boundary of 120a is positioned below the collecting lens 52. Then, the control means 8 controls the concentrating point position adjusting means not shown, and positions the irradiation position of the pulsed laser light irradiated from the concentrator 520 in the laser processing groove as shown in FIG. 9(b). The vicinity of the boundary between the side wall 120c of 120 and the bottom wall 120a. Next, the control means 8 controls the pulsed laser beam oscillating means 51 to illuminate the pulsed laser beam having a wavelength which is absorptive to the ruthenium substrate 10 from the concentrator 520, and controls the first galvanometer scanner 541 and the second. The angle adjustment actuator 541b and the angle adjustment actuator 542b of the galvanometer scanner 542 alternately change the first mirror 541a and the second mirror 542a to a dotted line state as shown in FIG. 2 or FIG. The state of the two-point chain line is controlled by the X-axis direction feeding means 37 to move the work chuck 36 at a predetermined feed speed in the X-axis direction (the direction perpendicular to the paper surface in FIG. 9(b)). 2 laser processing groove correction step). As a result, the boundary between the side wall 120c of the laser processing groove 120 and the bottom wall 120a is formed to be substantially a right angle as shown in Fig. 9(c).

By performing the first laser processing groove correction step and the second laser processing groove correction step as described above, the laser processing groove 120 formed on the ruthenium substrate 10 is corrected as shown in FIG. 9(c). The boundary between the side walls 120b, 120c and the bottom wall 120a is substantially at right angles.

Furthermore, when the first laser processing groove correction step and the second laser processing groove correction step are performed, the control may be configured as shown in FIG. The angle adjustment actuator 552b of the third galvanometer scanner 552 of the X-axis direction scanning unit 55 operates to interactively position the third mirror 552a to the position indicated by the broken line and the 2-point chain as shown in FIG. At the position indicated by the line, the laser beam is irradiated while the optical axis of the laser beam is oscillated in the X-axis direction with respect to the central axis of the condensing lens 52. Therefore, the formation of the laser processing groove 110 can be promoted.

The present invention has been described with reference to the embodiments shown in the drawings. However, the present invention is not limited to the embodiments, and various modifications may be made within the scope of the invention. For example, in the above-described embodiment, the Y-axis direction tilting unit 54 and the X-axis direction scanning unit 55 as the optical axis tilting means 53 are shown as an example using a galvanometer scanner, but the optical axis tilting means may also use sound. Optical element (AOE), electro-optical element (EOD), polygon mirror, etc.

5‧‧‧Laser light exposure

51‧‧‧Laser light oscillation

511‧‧‧YAG laser oscillator

512‧‧‧Repetition frequency setting means

52‧‧‧ Concentrating lens

520‧‧‧ concentrator

53‧‧‧ Optical axis tilting means

54‧‧‧Y-axis tilt unit

541‧‧‧1st galvanometer scanner

541a‧‧‧1st mirror

541b, 542b‧‧‧ Angle adjustment actuator

542‧‧‧2nd galvanometer scanner

542a‧‧‧2nd mirror

543‧‧‧ optical axis changing mirror

36‧‧‧Working table

P1, P2, P3‧‧‧ spotlights

W‧‧‧Processed objects

Y‧‧‧ arrow

Claims (3)

A laser processing apparatus including a workpiece holding means for holding a workpiece, a laser beam irradiation means for irradiating a laser beam to a workpiece held by the workpiece holding means, and a workpiece holding means and The X-axis direction feeding means for relatively moving the laser beam irradiation means in the machining feed direction (X-axis direction), and the Y-axis direction for causing the workpiece holding means and the laser beam irradiation means to be orthogonal to the X-axis direction a Y-axis direction feeding means for processing feed, characterized in that the laser beam irradiation means is provided with a laser beam oscillating means for oscillating to generate a laser beam, and the laser beam oscillating means a collecting lens that illuminates the generated laser light to illuminate the workpiece held on the working chuck, and a light disposed between the laser beam oscillating means and the collecting lens to cause the laser beam The axis is eccentric with respect to the central axis of the condensing mirror, and the optical axis of the laser beam is inclined on the condensing side with respect to the optical axis of the condensing lens. The laser processing apparatus of claim 1, wherein the optical axis tilting means is constituted by a tilting unit in a Y-axis direction for causing a laser beam oscillated from the laser beam oscillating means The optical axis moves in the Y-axis direction with respect to the central axis of the collecting lens. The laser processing apparatus of claim 2, wherein the optical axis tilting means is constituted by the Y-axis direction tilting unit and the X-axis direction scanning unit, and the X-axis direction scanning unit is configured to oscillate the laser light from the laser beam Oscillating The optical axis of the generated laser light moves in the X-axis direction with respect to the central axis of the collecting lens.