KR101819074B1 - Laser machining apparatus - Google Patents

Abstract

An object of the present invention is to improve processing productivity in a laser processing apparatus.
A laser machining apparatus according to the present invention is a laser machining apparatus for performing laser machining by relatively transferring and indexing a workpiece W held by a holding means and a laser irradiating means, The workpiece W is relatively processed and transferred, and the workpiece W is irradiated with a laser beam to perform laser processing on the workpiece. When the laser beam passes the workpiece W, the processing and feeding means is stopped, And control means for operating the indexing conveying means using the time of deceleration necessary for stopping. It is possible to start the next laser machining by using the deceleration time of the machining feed, so that the time required for the actual indexing feed can be set to zero, and the productivity of the laser machining can be improved.

Description

[0001] LASER MACHINING APPARATUS [0002]

The present invention relates to a laser machining apparatus for performing laser machining of a workpiece by relatively moving a holding means holding a workpiece and a laser irradiating means for irradiating the laser beam.

A wafer in which a plurality of devices such as ICs, LSIs, and LEDs are partitioned by the line to be divided and the wafer is formed on the surface is broken along the line to be divided after the laser beam is irradiated to the dividing line to perform grooving or internal processing , And they are used in various electronic devices and the like (see, for example, Patent Documents 1 and 2).

A laser processing apparatus for performing laser processing by irradiating a laser beam onto a wafer includes holding means for holding a workpiece and laser irradiation means for irradiating the workpiece held by the holding means with a laser beam to perform processing, The desired processing can be performed on the line to be divided of the wafer and the wafer can be divided into individual devices by moving the means and the laser irradiation means relatively in the processing transfer direction (X axis direction) and the indexing transfer direction (Y axis direction) 3).

In the laser machining apparatus, laser irradiation can be performed in both the forward path and the backward path when the holding means and the laser irradiation means are reciprocated relatively in the machining direction, There is an advantage that the machining efficiency is higher than that in the case of using a cutting device capable of machining only when moving in one direction.

Patent Publication No. Hei 10-305420 Patent No. 3408805 Patent Publication No. 2010-284671

However, even if it is intended to irradiate a laser beam through a condenser (irradiation head) to one line to be divided and stop the machining feed after the machining of the line to be divided is ended, there is an overrun until the machining feed is completely stopped So, it takes extra time. Further, after the machining feed is stopped, it takes time to perform the indexing feed for aligning the position of the concentrator to the next machining line to be machined. For example, when the overrun takes about one second, and the indexing transfer takes about 0.5 seconds, an extra time of about 1.5 seconds is required in addition to the machining time when machining one planned line to be divided have. Therefore, for example, for a wafer having 300 lines to be divided, a time of 450 seconds is required in addition to the machining time, and further improvement in productivity is demanded.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to further improve the productivity in the laser processing apparatus.

According to the present invention, there is provided a laser processing apparatus comprising: holding means for holding a workpiece; laser beam irradiating means for irradiating a laser beam to the workpiece held by the holding means to perform laser machining; Indexing means for indexing and transferring the holding means and the laser beam irradiating means relative to each other, and means for moving the holding means and the laser beam irradiating means Wherein the machining means includes a machining means for machining a workpiece to be machined, a machining means for machining the workpiece to be machined, a machining means for machining the workpiece, And to stop the machining feed from the stop command of the operation of the machining and feeding means There is provided a laser processing apparatus including control means for operating the indexing feeding means to perform indexing feed by using a time of deceleration.

In the present invention, the control means controls to perform the indexing feed in parallel with the deceleration at the time of deceleration from the end of the laser machining to the end of the machining feed for the one line to be divided, and the deceleration time So that the laser processing for the next line to be divided is started. Therefore, it is possible to substantially zero the time required for the indexing transfer, thereby improving the productivity of the laser processing.

1 is a perspective view showing an example of a laser machining apparatus;
2 is a plan view showing an example of a work piece;
3 is a perspective view showing a state in which laser processing is performed on a line to be divided of a workpiece;
4 is a plan view showing a change in the relative positional relationship between the irradiation head and the workpiece;

One. Laser processing  Configuration of the device

The laser machining apparatus 1 shown in Fig. 1 irradiates a laser beam from a laser irradiating means 3 to a work (work) W held by a holding means 2, .

The holding means 2 includes a holding surface 20 for holding the workpiece W by suction and a fixing portion 21 for fixing the frame 101 supporting the workpiece W via the tape 100 ). The fixing portion 21 is provided with a clamp 210 for pressing the frame 101 from above.

The holding means 2 is supported by the processing and conveying means 4 so as to be movable in the processing and conveying direction (X-axis direction), and is conveyed by the indexing conveying means 5, Direction (Y-axis direction). The processing transfer means 4 and the indexing transfer means 5 are controlled by the control means 6.

The processing and transfer means 4 includes a ball screw 40 disposed on a flat base 53 and having an axis in the X axis direction and a pair of guide rails A pulse motor 42 connected to one end of the ball screw 40 and a slide portion 42 having an inner nut threadedly engaged with the ball screw 40 and a lower portion slidably contacting with the guide rail 41 43). This machining and conveying means 4 is driven by the pulse motor 42 under the control of the control means 6 so that the slide portion 43 is moved on the guide rail 41 And the holding means 2 is moved in the X-axis direction by sliding in the X-axis direction.

The holding means 2 and the processing and conveying means 4 are supported by the indexing and conveying means 5 so as to be movable in the Y-axis direction. The indexing and conveying means 5 includes a ball screw 50 having an axis in the Y axis direction, a pair of guide rails 51 arranged in parallel with the ball screw 50, A connected pulse motor 52 and a base 53, which is not shown in the figure, is screwed to the ball screw 50 and the lower part thereof is in sliding contact with the guide rail 51. The indexing and conveying means 5 is driven by the pulse motor 52 under the control of the control means 6 so that the base 53 rotates on the guide rail 51 in the Y So that the holding means 2 and the machining transfer means 4 are moved in the Y-axis direction by sliding in the axial direction.

The laser irradiation means 3 includes a casing 30 fixed to the wall portion 10 and an irradiation head 31 fixed to the distal end portion of the casing 30. [ The irradiation head 31 has a function of irradiating a laser beam in a vertical direction. In the casing 30, a laser oscillator for oscillating a YAG laser or a YVO4 laser, a repetition frequency setting means, a pulse width adjusting means, and a power adjusting means are accommodated.

In the laser machining apparatus 1 shown in Fig. 1, the processing transfer means 4 and the indexing transfer means 5 move the holding means 2 in the X-axis direction and the Y- However, the present invention is not limited to the example shown in Fig. 1, provided that the holding means 2 and the laser irradiating means 3 are relatively moved in the X-axis direction and fed indexed in the Y-axis direction, For example, the holding means 2 may move in the X-axis direction and the laser irradiating means 3 may move in the Y-axis direction. Alternatively, the holding means 2 may not move, Axis direction and the Y-axis direction.

2. Laser-machined  Control

L22, L23, ... in the longitudinal direction are formed on the surface W1 of the work W shown in Fig. 2 by the dividing lines Lll, L12, L13, ... in the lateral direction and the dividing lines L21, So that a plurality of devices 102 are formed. In the following description, the line to be divided is simply referred to as a line.

The coordinates of both ends of each planned line to be divided in the X-Y coordinate system are recognized in advance by the control means 6. For example, the coordinates of the end portions A and B of the line L11 are (x1, y1) and (x2, y1), the coordinates of the end portions C and D of the line L12 are (x3, y2) (X5, y3) and (x6, y3), respectively. As shown in Fig. 3, based on these coordinate information, the control means 6 controls the work W held by the holding means 2 to reciprocate in the X1 direction and the X2 direction, Rays 310 are inspected.

In this laser processing, ablation processing for forming a groove by condensing a laser beam of a wavelength having an absorbing property with respect to the work W on the surface of the work W, It is possible to perform internal processing for condensing a laser beam having a transmittance wavelength and forming a modified layer therein.

In the ablation process, processing is performed under the following conditions, for example.

Light source: YAG laser or YV04 laser

Wavelength: 355 nm

Condensing spot diameter:? 1 占 퐉

Average power: 5 W

Repetition frequency: 100 ㎑

Scan speed: 100 mm / s

On the other hand, in the internal machining, machining is performed under the following conditions, for example.

Light source: YAG laser or YVO4 laser

Wavelength: 1064 nm

Condensing spot diameter:? 1 占 퐉

Average power: 1 W

Repetition frequency: 100 ㎑

Scan speed: 400 mm / s

Hereinafter, the control of the relative movement of the work W and the irradiation head 31 when the work W is laser-processed will be described. The processing described below is applicable to both ablation processing and internal processing.

(1) Step 1

For example, lines L11, L12, L13, ... The indexing and conveying means 5 shown in Fig. 1 is operated so that the Y coordinate y1 of the line L11 and the Y coordinate of the irradiation head 31 coincide with each other, So that the irradiation head 31 is positioned.

4, the holding means 2 and the laser irradiating means (not shown) are moved by moving the holding means 2 in the X-axis direction by operating the processing and conveying means 4 under the control of the control means 6 3 is relatively moved in the X1 direction and irradiation of the laser beam is started at the time when the irradiation head 31 is located at the irradiation head position 31a located immediately above the end A. When the end A is machined, I do. During the machining, the laser beam is continuously irradiated until the irradiation head 31 moves to the irradiation head position 31b located immediately above the end portion B,

(2) Step 2

The irradiation of the laser beam from the irradiation head 31 is stopped at the time when the processing of the line L11 is finished and the irradiation head 31 passes the work W and the irradiation of the laser beam is stopped by the processing means 4 under the control of the control means 6. [ To stop the machining feed. Although the holding means 2 is decelerated by the processing and conveying means 4, it takes time to completely stop after passing under the irradiation head position 31b. For example, it takes about 1 second to start the deceleration and completely stop.

(3) Step 3

The indexing and conveying means 5 is operated in the meantime by using the time of deceleration required for stopping the processing of the processing so that the holding means 2 and the laser irradiation means 3 are relatively indexed And the irradiation head 31 is positioned above the line L12. That is, the indexing transfer and the processing transfer are performed in parallel. For example, if it takes 0.5 seconds to carry out the indexing, as shown in Fig. 4, the irradiation head 31 reaches the irradiation head position 31c in 0.5 second, and thereafter is irradiated And moves to the head position 31d. The irradiation head position 31d is a starting position of machining feed for machining the line L12.

Normally, since the time required for deceleration of the machining feed is longer than the time required for the indexing feed, the indexing feed for machining the next line can be completed during the deceleration of the machining feed, .

Then, returning to the first step, the processing and transfer means 4 is operated to laser-process the line L12. At this time, the machining transfer means 4 moves the holding means 2 in the X2 direction, that is, in the direction opposite to the machining of the line L11. Laser irradiation is started when the irradiation head 31 is located at the position immediately above the end portion C and laser processing is performed until the irradiation head position 31e located just above the end portion D is reached.

Next, at the second step, the irradiation head 31 stops the irradiation of the laser beam from the irradiation head 31 at the time when the irradiation head 31 passes over the work W, and under the control of the control means 6, ) To stop the machining feed. During the deceleration of the holding means 2, the indexing feed and the processing feed are performed in parallel by the third step, the irradiation head 31 moves to the irradiation head position 31f, and thereafter, (31) moves to the irradiation head position 31g. Then, the process returns to the first step, and the irradiation head position 31g is set as the dawn start position of the machining feed and the line L13 is machined in the same manner. The first to third steps are repeated.

In this manner, the first to third steps are repeated, and laser processing is performed on all the lines while the holding means 2 is reciprocated. After the machining of the horizontal lines is completed, the holding means 2 is rotated by 90 degrees, and the laser processing is repeated for the vertical lines by repeating the first to third steps.

As described above, the control means 6 carries out the indexing feed in parallel with the deceleration at the time of the deceleration from the end of laser machining to the end of the machining feed, It is possible to start the laser processing for the line to be divided, so that the time required for actually carrying out the indexing can be made zero, and the productivity of the laser machining can be improved. In the conventional control which takes 1 second to decelerate the machining feed and 0.5 seconds to feed the indexing, 450 seconds have been consumed in addition to the machining time required for machining a workpiece having 300 lines to be divided, It can be shortened to 300 seconds, and productivity can be further improved.

1: Laser processing device 2: Holding means
20: maintaining surface 21:
3: laser processing means 30: casing
31: irradiation head 4: processing transfer means
40: ball screw 41: guide rail
42: motor 43:
5: Indexing conveying means 50: Ball screw
51: guide rail 52: motor
53: Base 6: Control means
10: wall portion
W: Work W1: Surface
L11 to L13, L21 to L23:
A to F: End portions 31a to 31f: irradiation head position
100: Tape 101: Frame
102:

Claims (1)

1. A laser processing apparatus for processing a circular workpiece having a plurality of lines to be divided, the surface of which is formed by irradiating a laser beam,
A laser irradiating means for irradiating the workpiece held by the holding means with a laser beam from an irradiation head to perform machining; and a processing device for relatively carrying out the processing for transferring the holding means and the laser irradiating means And an indexing conveying means for relatively indexing the holding means and the laser irradiating means,
A step of operating the machining and conveying means to relatively move and feed the holding means and the laser irradiating means to irradiate a laser beam to the line to be divided of the workpiece held by the holding means to perform machining, And stopping the machining feed operation by operating the machining feed means when the laser beam exceeds the workpiece; and operating the indexing feed means by using the time of deceleration necessary for stopping the machining feed to perform indexing feed And control means for performing the step of performing the step
Wherein the time of deceleration is longer than the time required for the indexing feed to complete the indexing feed for machining the next line to be divided within the time of the deceleration and after the completion of the indexing feed, And is located at a starting position of machining transfer on an extension line of the line to be divided.

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