WO2020090907A1

WO2020090907A1 - Laser machining device

Info

Publication number: WO2020090907A1
Application number: PCT/JP2019/042614
Authority: WO
Inventors: 剛志坂本; 惇治奥間
Original assignee: 浜松ホトニクス株式会社
Priority date: 2018-10-30
Filing date: 2019-10-30
Publication date: 2020-05-07
Also published as: KR20210082485A; JP7108517B2; CN112955278B; TWI825210B; JP2020069486A; TW202035055A; CN112955278A

Abstract

This laser machining device executes: first scanning processing in which, in a first state in which a control unit of the laser machining device, a first laser machining head and a second machining head are arranged in a line, a laser beam from the first laser machining head is scanned in a first direction with respect to the line, while the focal point of the laser beam from the first laser machining head is positioned in a first position in a third direction; and second scanning processing in which, in the first state, a laser beam from the second laser machining head is scanned in the first direction with respect to the line, while the focal point of the laser beam from the second laser machining head is positioned in a second position in the third direction.

Description

Laser processing equipment

The present disclosure relates to a laser processing device.

Patent Document 1 describes a laser processing apparatus that includes a holding mechanism that holds a work, and a laser irradiation mechanism that irradiates the work held by the holding mechanism with laser light. In the laser processing device described in Patent Document 1, a laser irradiation mechanism having a condenser lens is fixed to a base, and movement of a work along a direction perpendicular to the optical axis of the condenser lens is performed by a holding mechanism. Be implemented.

Japanese Patent No. 5456510

By the way, in the above laser processing apparatus, in order to improve the throughput, for example, it is possible to increase the moving speed of the work by the holding mechanism. However, even if an attempt is made to increase the moving speed of the work, the acceleration time required for the movement of the work to reach the uniform speed movement at the target speed also increases. Therefore, it is difficult to improve the throughput above a certain level by increasing the moving speed of the work. Thus, in the above technical field, improvement of throughput is desired.

On the other hand, in the above technical field, there is a case where a modified region is formed inside the work by irradiation with laser light and the work is cut using the modified region and a crack extending from the modified region. In particular, a plurality of rows of modified regions may be formed in the thickness direction of the work in order to sufficiently propagate cracks extending from the modified region. Even in such processing, improvement in throughput is also desired.

The present disclosure aims to provide a laser processing apparatus capable of improving throughput.

A laser processing apparatus according to the present disclosure is movable along a first direction, and a support portion for supporting an object along a first direction and a second direction intersecting the first direction, and a first direction. First laser processing head and second laser processing head for irradiating at least the inside of the object supported by the supporting portion with laser light to form a modified region, and a first laser processing head And a second laser processing head attached to the first mounting portion that is movable along a third direction that intersects the first direction and the second direction, and is movable along the third direction. A second mounting part, a first mounting part and a second mounting part, or a moving part that moves at least one of the supporting parts along the second direction, a supporting part, a moving part, a first mounting part, and The movement of the second mounting portion, the first laser processing head, and the second A laser beam is emitted from the laser processing head, and a control unit that controls the laser beam irradiation is provided, and a plurality of lines extending in the first direction and arranged in the second direction are set on the object. In the first state in which the first laser processing head and the second laser processing head are arranged on one of the plurality of lines, the control unit collects the laser light from the first laser processing head. A first scanning process of scanning the laser beam from the first laser processing head in the first direction with respect to one line while locating the light spot at the first position in the third direction; A second scan process of scanning the laser light from the second laser processing head in the first direction with respect to one line while locating the condensing point of the laser light from the laser processing head at the second position in the third direction. And run The second position is a position closer to the incident surface side of the laser light of the object than the first position in the third direction, and the control unit performs the first processing in the third processing. 2 The first scanning process and the laser beam focusing point of the laser beam from the laser processing head are separated from the laser beam focusing point of the first laser processing head by a distance L or more in the direction opposite to the first direction. The second scan process is executed.

In this device, the first laser processing head and the second laser processing head can be arranged along the first direction. Then, the control unit uses the first scan processing using the first laser processing head and the second laser processing head in the first state in which the first laser processing head and the second laser processing head are arranged on the line. Then, the second scan process is performed. In the first scan processing, the control unit scans the laser light from the first laser processing head in the first direction while setting the focal point of the laser light from the first laser processing head to the first position in the third direction. .. In the second scan processing, the control unit sets the converging point of the laser light from the second laser processing head to the second position in the third direction, and first controls the laser light from the second laser processing head with respect to the line. Scan in the direction. Accordingly, two lines of modified regions can be formed at least inside the object at substantially the same time by using two laser processing heads for one line.

Here, according to the knowledge of the present inventors, when one laser processing head is used, the position of the object is changed in the depth direction (third direction), and a plurality of scans are performed to change each position. The crack extending from the quality region can be sufficiently propagated. However, in this case, the throughput cannot be improved. On the other hand, when two rows of modified regions are formed inside the object using the two laser processing heads, the converging points of the laser beams from the respective laser processing heads coincide with each other in the first direction. If so, the crack extending from the modified region is unlikely to propagate. On the other hand, in this device, the condensing point of the laser light from the second laser processing head is located at a distance L or more from the converging point of the laser light from the first laser processing head in the direction opposite to the first direction. The first scan process and the second scan process are executed while being separated from each other. According to this, the laser from the second laser processing head that is scanned so as to follow the distance L while forming the modified region of the first row by scanning the laser beam from the preceding first laser processing head. The light can sufficiently propagate the crack while forming the modified region in the second row. Therefore, according to this device, the throughput can be improved.

In the laser processing apparatus according to the present disclosure, the control unit is configured such that, after the first processing, the first laser processing head and the second laser processing head are positioned on another line adjacent to one of the plurality of lines. In the arrayed second state, the laser beam from the first laser processing head is moved in the direction opposite to the first direction with respect to the line while the condensing point of the laser beam from the first laser processing head is located at the second position. In the third scanning process of scanning and in the second state, the laser light from the second laser processing head is positioned on the first position while the condensing point of the laser light from the second laser processing head is positioned at the first position. A fourth scanning process of scanning in a direction opposite to the first direction and a second processing process of executing the second processing process are performed. In the second processing process, the control unit condenses a laser beam from the first laser processing head. To While a position spaced apart in the first direction or the distance L than the focal point of the laser light from the second laser processing head may perform a third scan processing and the fourth scanning process. In this case, the first laser processing head and the second laser processing head are the first laser processing head and the second laser processing head in the forward path (first processing process) and the backward path (second processing process) with respect to the object by the first laser processing head and the second laser processing head. Laser processing can be preferably performed without changing the positions of the directions.

In the laser processing apparatus according to the present disclosure, the control unit may alternately and repeatedly execute the first processing and the second processing according to the number of lines. In this case, for example, the laser processing along all the lines can be performed by the reciprocating movement of the support portion along the first direction and the sequential movement of the first laser processing head and the second laser processing head in the second direction. It will be possible.

In the laser processing apparatus according to the present disclosure, the distance L may be 300 μm. According to the knowledge of the present disclosure, by setting the distance L to 300 μm in this way, the crack can be more sufficiently propagated.

In the laser processing apparatus according to the present disclosure, the first mounting portion and the second mounting portion are collectively mounted on the moving portion, and the moving portion moves the first mounting portion and the second mounting portion in the second direction. You may move. In this case, it becomes easy to move the first laser processing head and the second laser processing head in the second direction.

According to the present disclosure, it is possible to provide a laser processing device capable of improving throughput.

It is a perspective view of the laser processing apparatus of one embodiment. It is a front view of a part of laser processing apparatus shown by FIG. It is a front view of the laser processing head of the laser processing apparatus shown by FIG. 4 is a side view of the laser processing head shown in FIG. 3. FIG. It is a block diagram of the optical system of the laser processing head shown in FIG. It is a block diagram of the optical system of the laser processing head of a modification. It is a front view of a part of laser processing apparatus of a modification. It is a schematic top view which shows operation | movement of a laser processing apparatus. It is a schematic top view which shows operation | movement of a laser processing apparatus. It is a typical sectional view showing operation of a laser processing device. It is a graph which shows the amount of cracks. It is a figure which shows the modification of an attachment part and a laser processing head. It is a figure which shows the modification of an attachment part and a laser processing head. It is a figure which shows the modification of an attachment part and a laser processing head. It is a figure which shows the modification of an attachment part and a laser processing head.

Hereinafter, one embodiment will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts will be denoted by the same reference symbols and redundant description will be omitted.
[Configuration of laser processing equipment]

As shown in FIG. 1, the laser processing apparatus 1 includes a plurality of moving

mechanisms

5 and 6, a supporting portion 7, and a pair of laser processing heads (first laser processing head, second laser processing head) 10A and 10B. And a light source unit 8 and a control unit 9. Hereinafter, the first direction will be referred to as the X direction, the second direction perpendicular to the first direction will be referred to as the Y direction, and the third direction perpendicular to the first and second directions will be referred to as the Z direction. In this embodiment, the X direction and the Y direction are horizontal directions, and the Z direction is a vertical direction.

The moving mechanism 5 has a fixed portion 51, a moving portion 53, and a mounting portion 55. The fixed portion 51 is attached to the device frame 1a. The moving unit 53 is attached to a rail provided on the fixed unit 51, and can move along the Y direction. The attachment portion 55 is attached to a rail provided on the moving portion 53 and can move along the X direction.

The moving mechanism 6 includes a fixed part 61, a pair of moving parts (first moving part, second moving part) 63, 64, and a pair of mounting parts (first mounting part, second mounting part) 65, 66. And have. The fixed portion 61 is attached to the device frame 1a. Each of the pair of moving

portions

63 and 64 is attached to a rail provided on the fixed portion 61, and each of them can move independently along the Y direction. The attachment portion 65 is attached to a rail provided on the moving portion 63 and can move along the Z direction. The attachment portion 66 is attached to a rail provided on the moving portion 64 and can move along the Z direction. That is, with respect to the device frame 1a, each of the pair of mounting

portions

65 and 66 can move along the Y direction and the Z direction.

The support portion 7 is attached to a rotary shaft provided on the attachment portion 55 of the moving mechanism 5, and can rotate about an axis parallel to the Z direction as a center line. That is, the support part 7 can move along each of the X direction and the Y direction, and can rotate about the axis parallel to the Z direction as the center line. The support unit 7 supports the object 100 along the X direction and the Y direction. The object 100 is, for example, a wafer.

As shown in FIGS. 1 and 2, the laser processing head 10A (for example, the first laser processing head) is attached to the attachment portion 65 of the moving mechanism 6. The laser processing head 10A is for irradiating the object 100 supported by the support 7 with laser light (first laser light) L1 while facing the support 7 in the Z direction. The laser processing head 10B (for example, the second laser processing head) is attached to the attachment portion 66 of the moving mechanism 6. The laser processing head 10B is for irradiating the object 100 supported by the support 7 with laser light (second laser light) L2 while facing the support 7 in the Z direction.

The light source unit 8 has a pair of

light sources

81 and 82. The light source 81 outputs laser light L1. The laser light L1 is emitted from the emitting portion 81a of the light source 81 and guided to the laser processing head 10A by the optical fiber 2. The light source 82 outputs laser light L2. The laser light L2 is emitted from the emitting portion 82a of the light source 82, and is guided to the laser processing head 10B by another optical fiber 2.

The control unit 9 controls each unit of the laser processing apparatus 1 (a plurality of moving

mechanisms

5, 6, a pair of laser processing heads 10A, 10B, a light source unit 8, etc.). The control unit 9 is configured as a computer device including a processor, a memory, a storage, a communication device, and the like. In the control unit 9, the software (program) read into the memory or the like is executed by the processor, and the reading and writing of data in the memory and the storage and the communication by the communication device are controlled by the processor. Thereby, the control unit 9 realizes various functions.

An example of processing by the laser processing apparatus 1 configured as above will be described. An example of the processing is an example in which a modified region is formed inside the object 100 along each of a plurality of lines set in a grid pattern in order to cut the object 100, which is a wafer, into a plurality of chips. is there.

First, the moving mechanism 5 moves the supporting portion 7 along the X direction and the Y direction so that the supporting portion 7 supporting the object 100 faces the pair of laser processing heads 10A and 10B in the Z direction. To move. Then, the moving mechanism 5 rotates the support part 7 with the axis line parallel to the Z direction as the center line so that the plurality of lines extending in one direction on the object 100 are along the X direction.

Next, the moving mechanism 6 moves the laser processing head 10A along the Y direction so that the focus point of the laser beam L1 is located on one line extending in one direction. On the other hand, the moving mechanism 6 moves the laser processing head 10B along the Y direction so that the focal point of the laser light L2 is located on the other line extending in one direction. Then, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the focusing point of the laser beam L1 is located inside the object 100. On the other hand, the moving mechanism 6 moves the laser processing head 10B along the Z direction so that the focal point of the laser beam L2 is located inside the object 100.

Subsequently, the light source 81 outputs the laser light L1 and the laser processing head 10A irradiates the object 100 with the laser light L1, and the light source 82 outputs the laser light L2 and the laser processing head 10B lasers the object 100. The light L2 is emitted. At the same time, the condensing point of the laser light L1 relatively moves along one line extending in one direction (the laser light L1 is scanned), and the laser beam extends along another line extending in one direction. The moving mechanism 5 moves the support portion 7 along the X direction so that the focal point of the light L2 moves relatively (the laser light L2 is scanned). In this way, the laser processing apparatus 1 forms the modified region inside the object 100 along each of the plurality of lines extending in one direction on the object 100.

Then, the moving mechanism 5 rotates the support part 7 with the axis line parallel to the Z direction as the center line so that the plurality of lines extending in the other direction orthogonal to the one direction in the object 100 are along the X direction. ..

Subsequently, the moving mechanism 6 moves the laser processing head 10A along the Y direction so that the focus point of the laser light L1 is located on one line extending in the other direction. On the other hand, the moving mechanism 6 moves the laser processing head 10B along the Y direction so that the focus point of the laser light L2 is located on another line extending in the other direction. Then, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the focusing point of the laser beam L1 is located inside the object 100. On the other hand, the moving mechanism 6 moves the laser processing head 10B along the Z direction so that the focal point of the laser beam L2 is located inside the object 100.

Subsequently, the light source 81 outputs the laser light L1 and the laser processing head 10A irradiates the object 100 with the laser light L1, and the light source 82 outputs the laser light L2 and the laser processing head 10B lasers the object 100. The light L2 is emitted. At the same time, the focal point of the laser light L1 relatively moves along one line extending in the other direction (the laser light L1 is scanned), and the laser beam extends along the other line extending in the other direction. The moving mechanism 5 moves the support portion 7 along the X direction so that the focal point of the light L2 moves relatively (the laser light L2 is scanned). In this way, the laser processing apparatus 1 forms the modified region inside the object 100 along each of the plurality of lines extending in the other direction orthogonal to the one direction in the object 100.

In the example of the above-described processing, the light source 81 outputs the laser light L1 that is transmissive to the target object 100, for example, by the pulse oscillation method, and the light source 82 outputs the laser light L1 to the target object 100, for example, by the pulse oscillation method. On the other hand, the laser beam L2 having transparency is output. When such laser light is condensed inside the object 100, the laser light is particularly absorbed in a portion corresponding to the condensing point of the laser light, and a modified region is formed inside the object 100. The modified region is a region where the density, refractive index, mechanical strength, and other physical properties are different from the surrounding unmodified region. The modified region includes, for example, a melt-processed region, a crack region, a dielectric breakdown region, and a refractive index change region.

When the object 100 is irradiated with the laser light output by the pulse oscillation method and the condensing point of the laser light is relatively moved along the line set on the object 100, a plurality of modified spots are lined up. Are formed so as to be lined up in a row along the line. One modified spot is formed by irradiation with one pulse of laser light. The one-row reforming region is a set of a plurality of reforming spots arranged in one row. Adjacent modified spots may be connected to each other or may be separated from each other depending on the relative moving speed of the condensing point of the laser light with respect to the object 100 and the repetition frequency of the laser light.
[Configuration of laser processing head]

As shown in FIGS. 3 and 4, the laser processing head 10A includes a casing (for example, a first casing) 11, an incident unit 12, an adjusting unit 13, and a condensing unit (for example, a first condensing unit). 14 and.

The housing 11 has a first wall portion 21 and a second wall portion 22, a third wall portion 23 and a fourth wall portion 24, and a fifth wall portion 25 and a sixth wall portion 26. The first wall portion 21 and the second wall portion 22 face each other in the X direction. The third wall portion 23 and the fourth wall portion 24 face each other in the Y direction. The fifth wall portion 25 and the sixth wall portion 26 face each other in the Z direction.

The distance between the third wall portion 23 and the fourth wall portion 24 is smaller than the distance between the first wall portion 21 and the second wall portion 22. The distance between the first wall portion 21 and the second wall portion 22 is smaller than the distance between the fifth wall portion 25 and the sixth wall portion 26. The distance between the first wall portion 21 and the second wall portion 22 may be equal to the distance between the fifth wall portion 25 and the sixth wall portion 26, or alternatively, the fifth wall portion 25 and the sixth wall portion 26. It may be larger than the distance to the portion 26.

In the laser processing head 10A, the first wall portion 21 is located on the fixed portion 61 side of the moving mechanism 6, and the second wall portion 22 is located on the opposite side to the fixed portion 61. The third wall portion 23 is located on the mounting portion 65 side of the moving mechanism 6, and the fourth wall portion 24 is located on the side opposite to the mounting portion 65 and on the laser processing head 10B side (FIG. 2). That is, the fourth wall portion 24 is a facing wall portion that faces the housing (second housing) of the laser processing head 10B along the Y direction. The fifth wall portion 25 is located on the side opposite to the support portion 7, and the sixth wall portion 26 is located on the support portion 7 side.

The housing 11 is configured such that the housing 11 is attached to the mounting portion 65 with the third wall portion 23 arranged on the mounting portion 65 side of the moving mechanism 6. Specifically, it is as follows. The mounting portion 65 has a base plate 65a and a mounting plate 65b. The base plate 65a is attached to a rail provided on the moving unit 63 (see FIG. 2). The mounting plate 65b is erected on the end of the base plate 65a on the laser processing head 10B side (see FIG. 2). The casing 11 is attached to the attachment portion 65 by screwing the bolt 28 to the attachment plate 65b via the pedestal 27 while the third wall portion 23 is in contact with the attachment plate 65b. The pedestal 27 is provided on each of the first wall portion 21 and the second wall portion 22. The housing 11 is attachable to and detachable from the mounting portion 65.

The incident part 12 is attached to the fifth wall part 25. The incident unit 12 causes the laser light L1 to enter the housing 11. The incident portion 12 is offset to the second wall portion 22 side (one wall portion side) in the X direction and is offset to the fourth wall portion 24 side in the Y direction. That is, the distance between the incident portion 12 and the second wall portion 22 in the X direction is smaller than the distance between the incident portion 12 and the first wall portion 21 in the X direction, and the incident portion 12 and the fourth wall portion 24 in the Y direction. Is smaller than the distance between the incident portion 12 and the third wall portion 23 in the X direction.

The incident portion 12 is configured so that the connection end portion 2a of the optical fiber 2 can be connected. The connection end portion 2a of the optical fiber 2 is provided with a collimator lens that collimates the laser light L1 emitted from the emission end of the fiber, and is not provided with an isolator that suppresses return light. The isolator is provided in the middle of the fiber on the light source 81 side with respect to the connection end portion 2a. As a result, the connection end portion 2a is downsized, and the incident portion 12 is downsized. An isolator may be provided at the connection end 2a of the optical fiber 2.

The adjusting unit 13 is arranged in the housing 11. The adjusting unit 13 adjusts the laser light L1 incident from the incident unit 12. Each component of the adjusting unit 13 is attached to an optical base 29 provided inside the housing 11. The optical base 29 is attached to the housing 11 so as to partition the area inside the housing 11 into an area on the third wall portion 23 side and an area on the fourth wall portion 24 side. The optical base 29 is integrated with the housing 11. The components included in the adjusting unit 13 are attached to the optical base 29 on the fourth wall 24 side. Details of each configuration of the adjustment unit 13 will be described later.

The light collector 14 is arranged on the sixth wall 26. Specifically, the light collecting section 14 is arranged in the sixth wall section 26 in a state of being inserted into the hole 26 a formed in the sixth wall section 26. The condensing unit 14 condenses the laser light L1 adjusted by the adjusting unit 13 and emits it to the outside of the housing 11. The light collecting section 14 is offset to the second wall section 22 side (one wall section side) in the X direction and is biased to the fourth wall section 24 side in the Y direction. That is, the light condensing unit 14 is arranged so as to be biased toward the fourth wall portion (opposing wall portion) 24 side of the housing 11 when viewed from the Z direction. That is, the distance between the light collecting section 14 and the second wall section 22 in the X direction is smaller than the distance between the light collecting section 14 and the first wall section 21 in the X direction, and the light collecting section 14 and the fourth wall in the Y direction are fourth. The distance from the wall portion 24 is smaller than the distance between the light collecting portion 14 and the third wall portion 23 in the X direction.

As shown in FIG. 5, the adjusting unit 13 has an attenuator 31, a beam expander 32, and a mirror 33. The incident unit 12, the attenuator 31, the beam expander 32, and the mirror 33 of the adjusting unit 13 are arranged on a straight line (first straight line) A1 extending along the Z direction. The attenuator 31 and the beam expander 32 are arranged between the incident part 12 and the mirror 33 on the straight line A1. The attenuator 31 adjusts the output of the laser light L1 incident from the incident unit 12. The beam expander 32 expands the diameter of the laser light L1 whose output is adjusted by the attenuator 31. The mirror 33 reflects the laser light L1 whose diameter has been expanded by the beam expander 32.

The adjusting unit 13 further includes a reflective spatial light modulator 34 and an image forming optical system 35. The reflective spatial light modulator 34 of the adjustment unit 13, the imaging optical system 35, and the condensing unit 14 are arranged on a straight line (second straight line) A2 extending along the Z direction. The reflective spatial light modulator 34 modulates the laser light L1 reflected by the mirror 33. The reflective spatial light modulator 34 is, for example, a reflective liquid crystal (LCOS: Liquid Crystal on Silicon) spatial light modulator (SLM: Spatial Light Modulator). The image forming optical system 35 constitutes a double-sided telecentric optical system in which the reflecting surface 34a of the reflective spatial light modulator 34 and the entrance pupil surface 14a of the condensing unit 14 are in an image forming relationship. The image forming optical system 35 is composed of three or more lenses.

The straight line A1 and the straight line A2 are located on a plane perpendicular to the Y direction. The straight line A1 is located on the second wall portion 22 side (one wall portion side) with respect to the straight line A2. In the laser processing head 10A, the laser beam L1 enters the housing 11 from the incident part 12, travels on the straight line A1, is sequentially reflected by the mirror 33 and the reflective spatial light modulator 34, and then the straight line A2. The light travels upward and is emitted from the light collecting unit 14 to the outside of the housing 11. The order of arrangement of the attenuator 31 and the beam expander 32 may be reversed. Further, the attenuator 31 may be arranged between the mirror 33 and the reflective spatial light modulator 34. Further, the adjusting unit 13 may have other optical components (for example, a steering mirror arranged in front of the beam expander 32).

The laser processing head 10A further includes a dichroic mirror 15, a measurement unit 16, an observation unit 17, a drive unit 18, and a circuit unit 19.

The dichroic mirror 15 is arranged on the straight line A2 between the imaging optical system 35 and the condensing unit 14. That is, the dichroic mirror 15 is arranged in the housing 11 between the adjusting unit 13 and the light collecting unit 14. The dichroic mirror 15 is attached to the optical base 29 on the side of the fourth wall portion 24. The dichroic mirror 15 transmits the laser light L1. From the viewpoint of suppressing astigmatism, the dichroic mirror 15 may be, for example, a cube type or two plate types arranged so as to have a twist relationship.

The measuring unit 16 is arranged inside the housing 11 with respect to the adjusting unit 13 on the first wall 21 side (the side opposite to the one wall side). The measuring unit 16 is attached to the optical base 29 on the fourth wall 24 side. The measurement unit 16 outputs measurement light L10 for measuring the distance between the surface of the object 100 (for example, the surface on the side on which the laser light L1 is incident) and the light condensing unit 14, and through the light condensing unit 14. The measurement light L10 reflected by the surface of the object 100 is detected. That is, the measurement light L10 output from the measurement unit 16 is applied to the surface of the object 100 via the light condensing unit 14, and the measurement light L10 reflected on the surface of the object 100 passes through the light condensing unit 14. And is detected by the measuring unit 16.

More specifically, the measurement light L10 output from the measurement unit 16 is sequentially reflected by the beam splitter 20 and the dichroic mirror 15 attached to the optical base 29 on the side of the fourth wall 24, and then the light collection unit 14 outputs the light. It goes out of the housing 11. The measurement light L10 reflected on the surface of the object 100 enters the housing 11 from the light condensing unit 14, is sequentially reflected by the dichroic mirror 15 and the beam splitter 20, enters the measuring unit 16, and then the measuring unit 16 Detected in.

The observing unit 17 is arranged in the housing 11 on the first wall 21 side (the side opposite to the one wall side) with respect to the adjusting unit 13. The observation section 17 is attached to the optical base 29 on the side of the fourth wall section 24. The observation unit 17 outputs the observation light L20 for observing the surface of the object 100 (for example, the surface on the side where the laser light L1 is incident), and is reflected by the surface of the object 100 via the light condensing unit 14. The observation light L20 thus generated is detected. That is, the observation light L20 output from the observation unit 17 is applied to the surface of the object 100 via the light condensing unit 14, and the observation light L20 reflected by the surface of the object 100 passes through the light condensing unit 14. And is detected by the observation unit 17.

More specifically, the observation light L20 output from the observation unit 17 passes through the beam splitter 20, is reflected by the dichroic mirror 15, and is emitted from the condensing unit 14 to the outside of the housing 11. The observation light L20 reflected on the surface of the object 100 enters the housing 11 from the light condensing unit 14, is reflected by the dichroic mirror 15, passes through the beam splitter 20, and enters the observation unit 17, Detected at 17. The wavelengths of the laser light L1, the measurement light L10, and the observation light L20 are different from each other (at least the respective central wavelengths are deviated from each other).

The drive section 18 is attached to the optical base 29 on the side of the fourth wall section 24. The driving unit 18 moves the condensing unit 14 arranged on the sixth wall unit 26 along the Z direction by the driving force of the piezoelectric element, for example.

The circuit portion 19 is arranged on the third wall portion 23 side with respect to the optical base 29 in the housing 11. That is, the circuit unit 19 is arranged on the third wall 23 side with respect to the adjustment unit 13, the measurement unit 16, and the observation unit 17 in the housing 11. The circuit unit 19 is, for example, a plurality of circuit boards. The circuit unit 19 processes the signal output from the measurement unit 16 and the signal input to the reflective spatial light modulator 34. The circuit unit 19 controls the drive unit 18 based on the signal output from the measurement unit 16. As an example, the circuit unit 19 maintains the distance between the surface of the object 100 and the light condensing unit 14 constant based on the signal output from the measurement unit 16 (that is, the surface of the object 100). The drive unit 18 is controlled so that the distance from the condensing point of the laser light L1 is kept constant). The housing 11 is provided with a connector (not shown) to which wiring for electrically connecting the circuit unit 19 to the control unit 9 (see FIG. 1) and the like is connected.

Similar to the laser processing head 10A, the laser processing head 10B includes a housing (for example, a second housing) 11, an incident unit 12, an adjusting unit 13, and a light collecting unit (for example, a second light collecting unit) 14. A dichroic mirror 15, a measurement unit 16, an observation unit 17, a drive unit 18, and a circuit unit 19 are provided. However, each configuration of the laser processing head 10B is, as shown in FIG. 2, each configuration of the laser processing head 10A with respect to a virtual plane that passes through the midpoint between the pair of mounting

portions

65 and 66 and is perpendicular to the Y direction. Are arranged so as to have a plane symmetry relationship with (this is an example as described later).

For example, in the housing 11 of the laser processing head 10A, the fourth wall portion 24 is located on the laser processing head 10B side with respect to the third wall portion 23, and the sixth wall portion 26 is supported with respect to the fifth wall portion 25. It is attached to the attachment portion 65 so as to be located on the side of the portion 7. On the other hand, in the housing 11 of the laser processing head 10B, the fourth wall portion 24 is located on the laser processing head 10A side with respect to the third wall portion 23, and the sixth wall portion 26 is with respect to the fifth wall portion 25. Is attached to the attachment portion 66 so as to be located on the support portion 7 side. That is, also in the laser processing head 10B, the fourth wall portion 24 is a facing wall portion that faces the housing of the laser processing head 10A along the Y direction. Also in the laser processing head 10B, the light converging portion 14 is arranged so as to be biased toward the fourth wall portion (opposing wall portion) 24 side of the housing 11 when viewed from the Z direction.

The housing 11 of the laser processing head 10B is configured such that the housing 11 is attached to the mounting portion 66 with the third wall portion 23 arranged on the mounting portion 66 side. Specifically, it is as follows. The mounting portion 66 has a base plate 66a and a mounting plate 66b. The base plate 66a is attached to a rail provided on the moving unit 63. The mounting plate 66b is erected at the end of the base plate 66a on the laser processing head 10A side. The housing 11 of the laser processing head 10B is attached to the attachment portion 66 with the third wall portion 23 in contact with the attachment plate 66b. The housing 11 of the laser processing head 10B can be attached to and detached from the mounting portion 66.
[Operation and effect of laser processing head]

In the laser processing head 10A, since the light source that outputs the laser light L1 is not provided in the housing 11, the housing 11 can be downsized. Further, in the housing 11, the distance between the third wall portion 23 and the fourth wall portion 24 is smaller than the distance between the first wall portion 21 and the second wall portion 22, and the collection disposed on the sixth wall portion 26. The light portion 14 is biased toward the fourth wall portion 24 side in the Y direction. Thereby, when moving the housing 11 along the direction perpendicular to the optical axis of the light condensing unit 14, for example, it is assumed that another configuration (for example, the laser processing head 10B) is present on the fourth wall 24 side. Also, the condensing unit 14 can be brought close to the other configuration. Therefore, the laser processing head 10A may be suitable for moving the condensing unit 14 along the direction perpendicular to its optical axis.

Further, in the laser processing head 10A, the incident portion 12 is provided on the fifth wall portion 25 and is offset to the fourth wall portion 24 side in the Y direction. As a result, it is possible to effectively use the region such as disposing another configuration (for example, the circuit unit 19) in a region on the third wall 23 side with respect to the adjustment unit 13 in the region inside the housing 11. it can.

Further, in the laser processing head 10A, the condensing portion 14 is offset to the second wall portion 22 side in the X direction. Accordingly, when the housing 11 is moved along the direction perpendicular to the optical axis of the light condensing unit 14, for example, even if another configuration exists on the second wall 22 side, the other configuration is collected. The light unit 14 can be brought closer.

Further, in the laser processing head 10A, the incident portion 12 is provided on the fifth wall portion 25 and is offset to the second wall portion 22 side in the X direction. As a result, other regions (for example, the measuring unit 16 and the observing unit 17) are arranged in the region on the first wall 21 side with respect to the adjusting unit 13 in the region in the housing 11, and the region is effectively used. Can be used.

Further, in the laser processing head 10A, the measuring unit 16 and the observing unit 17 are arranged in the region on the first wall 21 side with respect to the adjusting unit 13 in the region inside the housing 11, and the circuit unit 19 is The dichroic mirror 15 is arranged on the side of the third wall portion 23 with respect to the adjustment unit 13 in the area inside the housing 11, and the dichroic mirror 15 is arranged between the adjustment unit 13 and the light collection unit 14 in the housing 11. ing. Thereby, the area in the housing 11 can be effectively used. Further, the laser processing apparatus 1 can perform processing based on the measurement result of the distance between the surface of the object 100 and the light condensing unit 14. Further, the laser processing apparatus 1 can perform processing based on the observation result of the surface of the object 100.

In the laser processing head 10A, the circuit section 19 controls the drive section 18 based on the signal output from the measuring section 16. Thereby, the position of the condensing point of the laser beam L1 can be adjusted based on the measurement result of the distance between the surface of the object 100 and the condensing unit 14.

Further, in the laser processing head 10A, the incident section 12, the attenuator 31, the beam expander 32, and the mirror 33 of the adjusting section 13 are arranged on the straight line A1 extending along the Z direction, and the adjusting section 13 is provided. The reflective spatial light modulator 34, the imaging optical system 35, the condensing unit 14, and the condensing unit 14 are arranged on a straight line A2 extending along the Z direction. Accordingly, the adjusting unit 13 including the attenuator 31, the beam expander 32, the reflective spatial light modulator 34, and the imaging optical system 35 can be configured compactly.

Further, in the laser processing head 10A, the straight line A1 is located closer to the second wall portion 22 than the straight line A2. As a result, another optical system (for example, the measuring unit 16 and the observing unit 17) using the light condensing unit 14 is provided in the region on the first wall 21 side with respect to the adjusting unit 13 in the region in the housing 11. When configured, the degree of freedom in the configuration of the other optical system can be improved.

The above-described actions and effects are similarly exhibited by the laser processing head 10B.
[Modification of laser processing head]

As shown in FIG. 6, the incident section 12, the adjusting section 13, and the light collecting section 14 may be arranged on a straight line A extending along the Z direction. According to this, the adjusting unit 13 can be configured compactly. In that case, the adjusting unit 13 may not include the reflective spatial light modulator 34 and the imaging optical system 35. Further, the adjusting unit 13 may include an attenuator 31 and a beam expander 32. According to this, the adjusting unit 13 including the attenuator 31 and the beam expander 32 can be configured compactly. The order of arrangement of the attenuator 31 and the beam expander 32 may be reversed.

Further, the laser light L1 is guided from the emitting portion 81a of the light source unit 8 to the incident portion 12 of the laser processing head 10A, and the laser light L2 from the emitting portion 82a of the light source unit 8 to the incident portion 12 of the laser processing head 10B. At least one of the light guides may be implemented by a mirror. FIG. 7 is a front view of a part of the laser processing apparatus 1 in which the laser light L1 is guided by the mirror. In the configuration shown in FIG. 7, the mirror 3 that reflects the laser light L1 moves so as to face the emitting portion 81a of the light source unit 8 in the Y direction and face the incident portion 12 of the laser processing head 10A in the Z direction. It is attached to the moving portion 63 of the mechanism 6.

In the configuration shown in FIG. 7, even if the moving unit 63 of the moving mechanism 6 is moved along the Y direction, the state in which the mirror 3 faces the emitting unit 81a of the light source unit 8 in the Y direction is maintained. Further, even if the mounting portion 65 of the moving mechanism 6 is moved along the Z direction, the state in which the mirror 3 faces the incident portion 12 of the laser processing head 10A in the Z direction is maintained. Therefore, regardless of the position of the laser processing head 10A, the laser light L1 emitted from the emitting portion 81a of the light source unit 8 can be reliably incident on the incident portion 12 of the laser processing head 10A. Moreover, it is possible to use a light source such as a high output long / short pulse laser, which is difficult to be guided by the optical fiber 2.

Further, in the configuration shown in FIG. 7, the mirror 3 may be attached to the moving unit 63 of the moving mechanism 6 so that at least one of the angle adjustment and the position adjustment can be performed. According to this, the laser light L1 emitted from the emission portion 81a of the light source unit 8 can be more reliably incident on the incidence portion 12 of the laser processing head 10A.

The light source unit 8 may have one light source. In that case, the light source unit 8 may be configured so that a part of the laser light output from one light source is emitted from the emitting portion 81a and the rest of the laser light is emitted from the emitting portion 82a.
[About operation of laser processing equipment]

Next, the operation of the laser processing apparatus 1 will be described. FIG. 8 is a schematic top view showing the operation of the laser processing apparatus. In the following figures, a schematic interior of the laser processing heads 10A and 10B is shown. As shown in FIG. 8, the object 100 is supported by the support portion 7. The symbol S in the figure represents an optical system other than the optical system related to the irradiation of the laser beams L1 and L2 for forming the modified region, such as the measurement unit 16 and the observation unit 17 described above. ing.

The laser processing apparatus 1 also includes a pair of alignment cameras AC having different magnifications. The alignment camera AC is attached to the attachment portion 66 together with the laser processing head 10B. The alignment camera AC images, for example, a device pattern or the like using light transmitted through the object 100. The image obtained by this is used for alignment of the irradiation positions of the laser beams L1 and L2 with respect to the object 100.

Incidentally, here, the laser processing head 10A and the laser processing head 10B are arranged along the X direction. In the laser processing head 10A and the laser processing head 10B, the mounting

portions

65 and 66 are provided on the second wall portion 22 of the laser processing head 10A and the laser processing head 10B. The mounting

portions

65 and 66 are collectively mounted on the extension member (moving portion) EM via the moving

portions

63 and 64. The extension member EM is attached to the fixed portion 61. The extension member EM is attached to a rail provided on the fixed portion 61 and can move along the Y direction. That is, here, the laser processing head 10A and the laser processing head 10B are configured to be movable in the Z direction independently of each other, while being configured to be collectively moved in the Y direction.

The target object 100 has a plurality of lines C extending along the X direction and arranged along the Y direction. The line C is a virtual line, but may be an actually drawn line. Although a plurality of lines extending along the Y direction and arranged along the X direction are also set in the object 100, the illustration thereof is omitted.

The laser processing device 1 performs laser processing along each line C under the control of the control unit 9. The laser processing apparatus 1 can perform various kinds of laser processing, but here, the laser processing for forming the modified region at least inside the object 100 will be exemplified. That is, the laser processing heads 10A and 10B are used here to irradiate at least the inside of the object 100 supported by the support 7 with the laser beams L1 and L2 to form the modified region.

Here, the control section 9 moves the support section 7, the mounting section 65, the mounting section 66, and the extension member EM and irradiates the laser beams L1 and L2 from the laser processing head 10A and the laser processing head 10B. Control. In the laser processing device 1, the control unit 9 executes the first processing process and the second processing process. The first processing process includes a first scan process and a second scan process. The second processing process includes a third scanning process and a fourth scanning process.

The first scanning process is a process of scanning one line C of the plurality of lines C with the laser light L1 from the laser processing head 10A in the X direction. The second scanning process is a process of scanning the one line C with the laser beam L2 from the laser processing head 10B in the X direction. The third scan process is a process of scanning another line C of the plurality of lines C with the laser beam L1 from the laser processing head 10A in a direction opposite to the X direction (X negative direction in the drawing). The fourth scan process is a process of scanning the other line C with the laser beam L2 from the laser processing head 10B in a direction opposite to the X direction.

When the control unit 9 scans the laser beams L1 and L2 in the X direction (or the opposite direction), first, the laser processing heads 10A and 10B are moved in the Y direction and the Z direction via the mounting

portions

65 and 66 and the extension member EM. The laser light L1 and the laser light L2 are moved so that the focal points of the laser lights L1 and L2 are positioned on the respective lines C at positions inside the object 100. Then, in that state, by moving the support portion 7 in the X direction, the condensing points of the laser lights L1 and L2 are moved in the object 100 along the line C in the X direction (or the opposite direction). Is.

Particularly, here, the control unit 9 executes the first scan process and the second scan process, and the third scan process and the fourth scan process so that they overlap at least in part of the time. That is, the control unit 9 causes the state in which the laser beam L1 is scanned and the state in which the laser beam L2 is scanned to be realized at least partially at the same time. That is, the control unit 9 operates the laser processing head 10A and the laser processing head 10B in an overlapping manner. Thereby, the throughput can be clearly improved as compared with the processing using one laser processing head.

Next, the operation of the laser processing apparatus 1 will be specifically described. Here, the control unit 9 first moves the laser processing heads 10A and 10B in the Y direction from the state shown in FIG. 8 to move the laser processing heads 10A and 10A. The laser processing head 10B is in the first state in which it is arranged on one line C of the plurality of lines C. Here, as an example, one line C is a line C that is located at one end of the object 100 in the second direction among the plurality of lines C. In FIG. 9, the modified region M is shown as a solid line for the sake of explanation, but it is not necessary that the modified region M is actually visible from the surface of the object 100.

In the first state, the control unit 9 moves the laser processing head 10A in the Z direction as necessary, so that the condensing point P1 of the laser beam L1 from the laser processing head 10A is at the first position in the Z direction. Position it. Further, in the first state, the control unit 9 moves the laser processing head 10B in the Z direction as necessary, so that the condensing point P2 of the laser beam L2 from the laser processing head 10B is at the second position in the Z direction. Located in. The second position is a position closer to the incident surface 100a side of the laser light L1 and L2 of the object 100 than the first position in the Z direction.

After setting the converging points P1 and P2 as described above, the control unit 9 moves the support unit 7 in the direction opposite to the X direction to cause the laser beam L1 from the laser processing head 10A to move to the one line C. A first scanning process for scanning in the X direction and a second scanning process for scanning the laser beam L2 from the laser processing head 10B in the X direction with respect to the one line C. To execute. As a result, inside the object 100, the modified region M1 is formed in the region corresponding to the first position, and the modified region M2 is formed in the region corresponding to the second position.

Here, in the first processing, the control unit 9 sets the focus point P2 of the laser light L2 from the laser processing head 10B to a distance L or more from the focus point P1 of the laser light L1 from the laser processing head 10A. The first scan process and the second scan process are performed while keeping the position (distance L in this case) away from the X direction (X negative direction: downstream side). Therefore, the modified region M1 is formed ahead of the modified region M2 by the distance L in the X direction. In other words, the modified region M2 is formed so as to follow the modified region M1 by the distance L. As shown in FIG. 11, in this way, a sufficient amount of cracks are propagated due to the formation of the modified region M2.

When the laser processing on the one line C is completed, the control unit 9 executes the second processing, which is the laser processing on another line C adjacent to the one line C among the plurality of lines C. That is, after the first processing, the control unit 9 first moves the laser processing heads 10A and 10B in the Y direction, so that the laser processing head 10A and the laser processing head 10B cause the laser processing head 10A and the laser processing head 10B to move among the plurality of lines C. The second state is arranged on another line C.

In the second state, the control unit 9 moves the laser processing head 10A in the Z direction to position the condensing point P1 of the laser beam L1 from the laser processing head 10A at the second position. In the second state, the control unit 9 moves the laser processing head 10B in the Z direction to position the condensing point P2 of the laser beam L2 from the laser processing head 10B at the first position. That is, in the second processing, the positions of the converging points P1 and P2 in the Z direction are exchanged with each other with respect to the first processing.

After setting the converging points P1 and P2 as described above, the control unit 9 moves the support unit 7 in the X direction (the direction opposite to the first processing process), so that the laser beam L1 from the laser processing head 10A. Scan processing for scanning the other line C in the opposite direction to the X direction, and scanning the laser beam L2 from the laser processing head 10B in the opposite direction to the other line C for the third line. The fourth scan process and the second processing process for executing the process are executed. As a result, the modified region M is formed inside the object 100 in the regions corresponding to the first position and the second position.

Here, in the second processing, the control unit 9 sets the focus point P1 of the laser beam L1 from the laser processing head 10A at a distance L or more from the focus point P2 of the laser beam L2 from the laser processing head 10B. The third scan processing and the fourth scan processing are executed while the positions are separated in the X direction (upstream side) (here, the distance L). Therefore, the modified region M2 is formed ahead of the modified region M1 by the distance L in the X direction. In other words, the modified region M1 is formed so as to follow the modified region M2 by the distance L. By doing so, the amount of cracks developed by forming the modified region M1 becomes sufficient.

The control unit 9 alternately and repeatedly executes the above-described first machining process and second machining process a number of times (for all lines C) according to the number of the plurality of lines C. As a result, the modified regions M1 and M2 are formed for all the lines C, and the cracks extending from the modified regions M1 and M2 can be sufficiently propagated. Thereafter, if necessary, the support portion 7 is rotated to set a line intersecting the line C so as to be along the X direction, and the above operation can be repeated.
[Operation and effect of laser processing apparatus]

As described above, the laser processing apparatus 1 is movable along the X direction, and the support portion 7 for supporting the object 100 along the X direction and the Y direction intersecting the X direction, and the X direction. Laser processing heads 10A and 10B for forming the modified region M by irradiating at least the inside of the object 100 supported by the support portion 7 with the laser beams L1 and L2. Further, in the laser processing apparatus 1, the laser processing head 10A is attached and the mounting portion 65 which is movable along the Z direction and the laser processing head 10B which is mounted so that the laser processing head 10A is movable along the Z direction. A portion 66 and an extension member EM that moves the

attachment portions

65 and 66 along the Y direction are provided. Further, the laser processing apparatus 1 controls the movement of the support portion 7, the extension member EM, the mounting portion 65, and the mounting portion 66, and the irradiation of the laser beams L1 and L2 from the laser processing heads 10A and 10B. The controller 9 is provided.

A plurality of lines C extending along the X direction and arranged along the Y direction are set on the object 100. In the first state in which the laser processing heads 10A and 10B are arranged on one line C of the plurality of lines C, the control unit 9 sets the focus point P1 of the laser light L1 from the laser processing head 10A in the Z direction. In the first state, the laser beam L1 from the laser processing head 10A is scanned in the X direction with respect to the one line C, and the laser beam from the laser processing head 10B is in the first state. A second scan process of scanning the laser beam L2 from the laser processing head 10B in the X direction with respect to one line while locating the condensing point P2 of the light L2 at the second position in the Z direction. 1 Perform processing. The second position is a position closer to the incident surface 100a side of the laser light L1 and L2 of the object 100 than the first position in the Z direction. Then, in the first processing, the control unit 9 sets the focus point P2 of the laser beam L2 from the laser processing head to a distance L or more in the X direction from the focus point P1 of the laser beam L1 from the laser processing head 10A. The first scan process and the second scan process are executed while the positions are separated in the opposite direction.

In this laser processing apparatus 1, the laser processing heads 10A and 10B can be arranged along the X direction. Then, the control unit 9 performs the first scan processing using the laser processing head 10A and the second scanning processing using the laser processing head 10B in the first state in which the laser processing heads 10A and 10B are arranged on the line C. And execute. In the first scan processing, the control unit 9 scans the laser light L1 in the X direction while setting the focal point P1 of the laser light L1 from the laser processing head 10A at the first position in the Z direction. In the second scan process, the control unit 9 scans the laser beam L2 in the X direction with respect to the line C while setting the focal point P2 of the laser beam L2 from the laser processing head 10B to the second position in the Z direction. As a result, two rows of the modified regions M can be formed at least inside the object 100 at substantially the same time by using the two laser processing heads 10A and 10B for one line C.

Here, according to the knowledge of the present inventors, when one laser processing head is used, the position of the object is changed in the depth direction (Z direction) and scanning is performed a plurality of times, so that each modification is performed. A crack extending from the area can be sufficiently propagated. However, in this case, the throughput cannot be improved. On the other hand, when the two rows of modified regions M are formed inside the object 100 using the two laser processing heads 10A and 10B, the laser beams L1 from the respective laser processing heads 10A and 10B. When the converging points P1 and P2 of L2 are aligned in the X direction, the crack extending from the modified region M is unlikely to propagate.

On the other hand, in the laser processing apparatus 1, the focus point P2 of the laser beam L2 from the laser processing head 10B is located at a distance L or more in the X direction from the focus point P1 of the laser beam L1 from the laser processing head 10A. The first scan process and the second scan process are executed while being spaced apart in the opposite direction. According to this, the laser from the laser processing head 10B that is scanned so as to follow the distance L while forming the modified region M1 in the first row by scanning the laser beam L1 from the preceding laser processing head 10A. The light L2 can sufficiently propagate the crack while forming the modified region M2 in the second row. Therefore, according to the laser processing device 1, the throughput can be improved.

Further, in the laser processing apparatus 1, the control unit 9 in the second state in which the laser processing heads 10A and 10B are arranged on another line C after the first processing is in the second state, and the converging point P1 of the laser light L1. Scanning process in which the laser beam L1 is scanned in the direction opposite to the X direction with respect to the line C while the laser beam L1 is positioned at the second position, and the condensing point P2 of the laser beam L2 is positioned at the first position in the second state. While performing the above, the fourth processing for scanning the laser beam L2 in the direction opposite to the X direction with respect to the line C and the second processing for executing the second processing are performed. In the second processing, the control unit 9 sets the condensing point P1 of the laser light L1 at a position separated from the condensing point P2 of the laser light L2 by a distance L or more in the X direction, while performing the third scanning process and the third 4 Scan processing is executed. Therefore, the laser processing heads 10A and 10B can be suitably used without switching the positions of the laser processing heads 10A and 10B in the X direction in the forward path (first processing process) and the backward path (second processing process) with respect to the object 100. Laser processing becomes possible.

Further, in the laser processing apparatus 1, the control unit 9 alternately and repeatedly executes the first processing and the second processing according to the number of the plurality of lines C. Therefore, for example, the reciprocating operation of the support portion 7 along the X direction and the sequential movement of the laser processing heads 10A and 10B in the Y direction enable laser processing along all the lines C.

Moreover, in the laser processing apparatus 1, the distance L is 300 μm. According to the knowledge of the present inventor, by setting the distance L to 300 μm in this way, the crack can be more sufficiently propagated.

Further, in the laser processing apparatus 1, the mounting

portions

65 and 66 are collectively mounted on the extension member EM, and the extension member EM moves the mounting

portions

65 and 66 in the Y direction. In this case, the laser processing heads 10A and 10B can be easily moved in the Y direction.

In the laser processing apparatus 1, the laser processing head 10A is provided on the housing 11 and the sixth wall portion 26 of the housing 11 on the side of the support portion 7 and faces the object 100 supported by the support portion 7. And a condenser 14 for condensing the laser light L1. Further, the laser processing head 10B is also provided on the housing 11 and the sixth wall portion 26 of the housing 11 on the side of the support portion 7 and focuses the laser light L2 toward the object 100 supported by the support portion 7. And a light condensing unit 14 for Further, the

attachment portions

65 and 66 are attached to the wall portions (here, the second wall portion 22) different from the fourth wall portion 24 (opposing wall portion) facing each other along the X direction in the housing 11. ing. Then, the light collecting units 14 are arranged so as to be biased toward the fourth wall portion 24 side of the housing 11 when viewed from the Z direction.

Therefore, the mounting

portions

65 and 66 are not interposed between the laser processing head 10A and the laser processing head 10B. Therefore, the laser processing head 10A and the laser processing head 10B can be closer to each other in the Y direction. Further, the light converging portions 14 of the laser processing heads 10A and 10B are arranged so as to be biased toward the fourth wall portions 24 of the respective casings 11 facing each other. Therefore, when the laser processing head 10A and the laser processing head 10B are brought close to each other, the distance between the condensing sections 14 can be further reduced. As a result, the degree of freedom in setting the distance L is improved.
[Modification]

The above embodiment illustrates one embodiment of the laser processing apparatus. Therefore, the laser processing apparatus according to the present disclosure is not limited to the laser processing apparatus 1 described above, and can be arbitrarily modified.

12 to 15 are views showing modified examples of the mounting portion and the laser processing head. As shown in FIG. 12A, the mounting portion 65 is provided on the first wall portion 21 of the housing 11 of the laser processing head 10A, while the mounting portion 66 is mounted on the first wall of the housing 11 of the laser processing head 10B. You may provide in the part 21. Further, as shown in FIG. 12B, while the mounting portion 65 is provided on the third wall portion 23 of the housing 11 of the laser processing head 10A, the mounting portion 66 is mounted on the housing 11 of the laser processing head 10B. In the aspect provided in the third wall portion 23, the positions of the moving

portions

63 and 64 in the

attachment portions

65 and 66 may be staggered in the X direction. Further, as shown in FIG. 12C, the mounting portion 65 is provided on the third wall portion 23 of the housing 11 of the laser processing head 10A, while the mounting portion 66 is mounted on the housing 11 of the laser processing head 10B. In the aspect of providing the third wall portion 23, the positions of the moving

portions

63 and 64 in the

attachment portions

65 and 66 in the Y direction may be changed.

As shown in FIG. 13A, the mounting portion 65 is provided on the fifth wall portion 25 of the housing 11 of the laser processing head 10A, while the mounting portion 66 is mounted on the housing 11 of the laser processing head 10B. It may be provided on the five wall portion 25. Further, as shown in FIG. 13B, the mounting portion 65 is provided on the sixth wall portion 26 of the housing 11 of the laser processing head 10A, while the mounting portion 66 is mounted on the sixth wall portion of the housing 11 of the laser processing head 10B. It may be provided on the six wall portion 26. As described above, the

attachment portions

65 and 66 may be attached to the wall portions different from the fourth wall portion 24 facing each other along the X direction. Further, as shown in (c) of FIG. 13, while increasing the distance between the first wall portion 21 and the second wall portion 22, the condensing portion 14 is provided in the central portion of the housing 11 in the Y direction. Good.

Further, as in the above example, the laser processing apparatus 1 does not have to use the laser processing head 10A and the laser processing head 10B as the pair of laser processing heads. That is, in the laser processing apparatus 1, as shown in FIG. 14, a pair (one type) of laser processing head 10A is used, or as shown in FIG. 15, a pair of (another type) laser is used. The processing head 10B can be used. In these cases, the laser processing heads 10A and 10B on one side are rotated by 180 ° about the Z-axis direction with respect to the laser processing heads 10A and 10B on the other side, respectively. They are arranged so that their center positions coincide with each other. In these cases, it is not necessary to prepare two types of laser processing heads. Even in these cases, as shown in the drawings of FIG. 14 and the drawings of FIG. 15, the mounting

portions

65 and 66 are provided on the first wall portion 21 and the second wall portion 22, and the third wall portion is provided. You may provide in the wall part 23.

In the above example, the control unit 9 mechanically operates the laser processing heads 10A and 10B as a mode in which the focus points P1 and P2 of the laser beams L1 and L2 from the laser processing heads 10A and 10B are moved in the Z direction. An example was given in which the is moved in the Z direction. However, in the laser processing apparatus 1, the control unit 9 controls the adjustment unit 13 (for example, the reflective spatial light modulator 34) to optically move the focal points P1 and P2 in the Z direction. It may be.

Further, in the above example, as an example of the moving portion that moves at least one of the mounting

portions

65 and 66 and the support portion 7 along the Y direction, the extension member EM to which the mounting

portions

65 and 66 are collectively attached is used. Listed. However, the moving unit may be the moving unit 53 of the moving mechanism 5 that moves the support unit 7 in the Y direction.

The control unit 9 processes the object 100 at the wavelengths different from each other by the laser beam L1 from the laser processing head 10A and the laser beam L2 from the laser processing head 10B, and at the converging position in the Z direction. You may make it perform a process (multi-wavelength processing). The multi-wavelength processing is performed, for example, when processing a wafer in which silicon (Si) and glass are bonded (first case) or when a part of the laser beams L1 and L2 incident from the back surface side is absorbed by the device. This can be used, for example, when processing a wafer in which circuit damage may occur (second case).

In the first case, both the light with a wavelength for processing silicon (for example, 1064 nm) and the light with a wavelength for processing glass (for example, 532 nm) need to reach the target material, so processing is performed from the glass side. The converging position of the laser beam L1 from the laser processing head 10A is aligned in the silicon through the glass, and the converging position of the laser beam L2 from the laser processing head 10B is aligned in the glass, and processing is performed at the corresponding wavelength. To do. In order to process a wafer in which two different kinds of base materials are bonded together by multi-wavelength processing, the wavelength for processing the lower part of the wavelength is the wavelength that transmits the upper base material. Need to be Here, since the multi-wavelength processing is performed using the pair of laser processing heads 10A and 10B, the throughput can be improved.

On the other hand, in the second case, the focus position of the laser beam L1 from the laser processing head 10A is set near the device, and the focus position of the laser beam L2 from the laser processing head 10B is set at a position away from the device. To do. The wavelength of the laser light L1 is set to a wavelength (for example, 1064 nm) at which the base material has more absorption so that the amount of light passing to the device side is reduced, and the wavelength of the laser light L2 is set to a value even if some light is emitted. The wavelength (for example, 1342 nm) longer than the wavelength of the laser beam L1 suitable for processing the base material can be set.

A laser processing device that can improve throughput is provided.

DESCRIPTION OF SYMBOLS 1 ... Laser processing device, 7 ... Support part, 9 ... Control part, 10A ... Laser processing head (1st laser processing head), 10B ... Laser processing head (2nd laser processing head), 65 ... Mounting part (1st mounting) Part), 66 ... Mounting part (second mounting part), 100 ... Object, C ... Line, L1, L2 ... Laser light, P1, P2 ... Focus point.

Claims

A support unit configured to be movable along a first direction and supporting an object along the first direction and a second direction intersecting the first direction;
A first laser processing head and a second laser processing head, which are arranged along the first direction and irradiate at least the inside of the object supported by the support portion with laser light to form a modified region; ,
A first mounting portion to which the first laser processing head is mounted and which is movable along a third direction intersecting the first direction and the second direction;
A second mounting portion to which the second laser processing head is mounted and which is movable along the third direction;
A moving part that moves at least one of the first mounting part and the second mounting part, or the supporting part along the second direction;
Control of movement of the support portion, the moving portion, the first mounting portion, and the second mounting portion, and irradiation of the laser light from the first laser processing head and the second laser processing head. And a control unit for performing,
In the object, a plurality of lines extending along the first direction and arranged along the second direction are set,
The control unit is
In a first state in which the first laser processing head and the second laser processing head are arranged on one line of the plurality of lines, a converging point of the laser light from the first laser processing head is set. A first scanning process of scanning the laser beam from the first laser processing head in the first direction with respect to the one line while locating the laser beam at a first position in the third direction;
In the first state, while the condensing point of the laser light from the second laser processing head is located at the second position in the third direction, the laser light from the second laser processing head is moved to the first position. A second scanning process for scanning the line in the first direction, and a first processing process for executing the second scanning process,
The second position is a position closer to the incident surface side of the laser light of the object than the first position in the third direction,
In the first processing, the control unit sets the focus point of the laser light from the second laser processing head to a distance L or more from the focus point of the laser light from the first laser processing head. The first scan process and the second scan process are performed while the positions are separated from each other in the direction opposite to the first direction.
Laser processing equipment.
The control unit is configured such that, after the first processing, the first laser processing head and the second laser processing head are arranged on another line adjacent to the one line of the plurality of lines. In the second state, while the condensing point of the laser light from the first laser processing head is located at the second position, the laser light from the first laser processing head is moved in the first direction with respect to the line. A third scan process that scans in the opposite direction,
In the second state, the laser beam from the second laser processing head is moved to the another line while the focal point of the laser beam from the second laser processing head is positioned at the first position. A fourth scanning process of scanning in a direction opposite to the first direction, and a second processing process of performing
In the second processing, the control unit sets the focus point of the laser light from the first laser processing head to a distance L or more from the focus point of the laser light from the second laser processing head. The third scan process and the fourth scan process are performed while the positions are separated in the first direction.
The laser processing apparatus according to claim 1.
The control unit alternately and repeatedly executes the first processing processing and the second processing processing a number of times corresponding to the number of the plurality of lines.
The laser processing apparatus according to claim 2.
The distance L is 300 μm,
The laser processing apparatus according to any one of claims 1 to 3.
The first mounting portion and the second mounting portion are collectively mounted on the moving portion,
The moving part moves the first mounting part and the second mounting part in the second direction,
The laser processing apparatus according to any one of claims 1 to 4.