KR102685373B1 - laser processing device - Google Patents

Abstract

In a first state in which the control unit of the laser processing device, the first laser processing head, and the second laser processing head are arranged on a line, the converging point of the laser light from the first laser processing head is set to a first position in the third direction. A first scanning process of scanning the laser light from the first laser processing head in a first direction with respect to the line while positioning the laser processing head in a first direction, and condensing the laser light from the second laser processing head in the first state. A second scan process is performed to scan the laser light from the second laser processing head in the first direction with respect to the line while positioning the point at the second position in the third direction.

Description

laser processing device

This disclosure relates to a laser processing device.

Patent Document 1 describes a laser processing device that includes a holding mechanism for holding a workpiece and a laser irradiation mechanism for irradiating laser light to the workpiece held in the holding mechanism. In the laser processing device described in Patent Document 1, a laser irradiation mechanism having a condensing lens is fixed to a base, and movement of the workpiece along a direction perpendicular to the optical axis of the condensing lens is performed by a holding mechanism.

Patent Document 1: Japanese Patent No. 5456510

However, in the laser processing apparatus described above, in order to improve throughput, for example, it is considered to increase the moving speed of the workpiece by the holding mechanism. However, even if the movement speed of the work is attempted to be increased, the acceleration time required for the work to move at a constant speed at the target speed also increases. For this reason, it is difficult to improve throughput beyond a certain level by increasing the moving speed of the workpiece. In this way, in the above technical fields, improvement in throughput is desired.

On the other hand, in the above technical field, there are cases where a modified region is formed inside a workpiece by irradiation of laser light, and the workpiece is cut using the modified region and a crack extending from the modified region. In particular, in order to sufficiently advance cracks extending from the modified region, there are cases where multiple rows of modified regions are formed in the thickness direction of the work. In such processing, improvement in throughput is similarly desired.

The purpose of this disclosure is to provide a laser processing device capable of improving throughput.

The laser processing device according to the present disclosure is movable along a first direction, has a support portion for supporting an object along a first direction and a second direction intersecting the first direction, and is arranged along the first direction, A first laser processing head and a second laser processing head for forming a modified area by irradiating laser light to at least the inside of the object supported on the support, the first laser processing head is mounted, and the first laser processing head is installed in a first direction and A first mounting portion capable of moving along a third direction intersecting the second direction, a second mounting portion equipped with a second laser processing head, and capable of moving along a third direction, the first mounting portion and the second mounting portion , or, a moving part that moves at least one of the support parts along the second direction, a movement of the support part, the moving part, the first mounting part, and the second mounting part, and the movement of the first laser processing head and the second laser processing head. It is provided with a control part which controls the irradiation of a laser beam, A plurality of lines extending along a 1st direction and arranged along a 2nd direction are set to an object, The control part is comprised of a 1st laser processing head and a 2nd laser. In the first state in which the processing heads are arranged on one of the plurality of lines, the converging point of the laser light from the first laser processing head is positioned at the first position in the third direction, and the A first scan process of scanning a laser beam in a first direction with respect to one line, and, in the first state, positioning the convergence point of the laser beam from the second laser processing head at a second position in the third direction, 2 A first processing process is performed to perform a second scanning process in which the laser light from the laser processing head is scanned in a first direction with respect to one line, and the second position is located at a position closer to the object than the first position with respect to the third direction. is a position on the side of the incident surface of the laser beam, and in the first processing, the control unit sets the convergence point of the laser beam from the second laser processing head in the first direction at a distance L or more than the convergence point of the laser beam from the first laser processing head. The first scan process and the second scan process are performed while maintaining positions spaced apart in opposite directions.

In this device, the first laser processing head and the second laser processing head may be arranged along the first direction. And, the control unit performs a first scan process using the first laser processing head and a second scan using the second laser processing head in a first state in which the first laser processing head and the second laser processing head are arranged on a line. Execute processing. In the first scan process, the control unit scans the laser light from the first laser processing head in the first direction while setting the converging 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 scans the laser light from the second laser processing head in the first direction with respect to the line while setting the converging point of the laser light from the second laser processing head to the second position in the third direction. . As a result, two rows of modified regions can be formed almost simultaneously within at least the interior of the object using two laser processing heads for one line.

Here, according to the present inventors' knowledge, when using one laser processing head, cracks extending from each modified region can be sufficiently removed by performing multiple scans at different positions in the depth direction (third direction) of the object. progress can be made. However, in this case, improvement in throughput is not achieved. In contrast, when two rows of modified regions are formed inside an object using two laser processing heads, if the converging points of the laser light from each laser processing head are aligned with respect to the first direction, the modified regions expand from the modified regions. It is difficult for cracks to progress. In contrast, in this device, the first scan is performed while positioning the convergence point of the laser light from the second laser processing head at a distance L or more in the opposite direction to the first direction than the convergence point of the laser light from the first laser processing head. Execute processing and second scan processing. According to this, the first row of modified regions is formed by scanning the laser light from the preceding first laser processing head, and the second row is formed by the laser light from the second laser processing head that is scanned so as to follow it by a distance L. It is possible to sufficiently advance the crack while forming a reformed zone. Therefore, with this device, throughput can be improved.

In the laser processing device according to the present disclosure, the control unit, after the first processing, is in a second state in which the first laser processing head and the second laser processing head are arranged on another line adjacent to one line among the plurality of lines. , a third scan process of scanning the laser light from the first laser processing head in a direction opposite to the first direction with respect to the line while positioning the converging point of the laser light from the first laser processing head at the second position, and a second state. In this, a fourth scan process is performed to scan the laser light from the second laser processing head in a direction opposite to the first direction with respect to another line while positioning the converging point of the laser light from the second laser processing head at the first position. Performing the second processing, the control unit moves the converging point of the laser beam from the first laser processing head in the first direction by a distance L or more from the converging point of the laser beam from the second laser processing head. It is okay to perform the third scan process and the fourth scan process while maintaining one position. In this case, on the outbound route (first processing) and return route (second processing) to the object of the first laser processing head and the second laser processing head, the first laser processing head and the second laser processing head Laser processing is preferably possible without changing the position of the laser processing head in the first direction.

In the laser processing device according to the present disclosure, the control unit may alternately and repeatedly execute the first processing and the second processing as many times as the number of lines corresponds to the number of lines. In this case, for example, laser processing along all lines is possible by reciprocating motion of the support portion along the first direction and sequential movement of the first laser processing head and the second laser processing head in the second direction. It becomes.

In the laser processing device according to the present disclosure, the distance L may be 300 μm. According to the present initiator's knowledge, by setting the distance L to 300 μm in this way, the crack can grow more sufficiently.

In the laser processing device 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 may move the first mounting portion and the second mounting portion in the second direction. In this case, movement of the first laser processing head and the second laser processing head in the second direction becomes easy.

According to the present disclosure, a laser processing device capable of improving throughput can be provided.

1 is a perspective view of a laser processing device according to one embodiment.
FIG. 2 is a front view of a portion of the laser processing device shown in FIG. 1.
FIG. 3 is a front view of the laser processing head of the laser processing device shown in FIG. 1.
FIG. 4 is a side view of the laser processing head shown in FIG. 3.
FIG. 5 is a configuration diagram of the optical system of the laser processing head shown in FIG. 3.
Figure 6 is a configuration diagram of the optical system of a laser processing head of a modified example.
Fig. 7 is a front view of a portion of a laser processing device of a modified example.
Figure 8 is a schematic top view showing the operation of the laser processing device.
Figure 9 is a schematic top view showing the operation of the laser processing device.
Figure 10 is a schematic cross-sectional view showing the operation of the laser processing device.
Figure 11 is a graph showing the amount of cracking.
12 is a diagram showing a modified example of the mounting portion and the laser processing head.
Figure 13 is a diagram showing a modified example of the mounting portion and laser processing head.
Figure 14 is a diagram showing a modified example of the mounting portion and the laser processing head.
Figure 15 is a diagram showing a modified example of the mounting portion and laser processing head.

Hereinafter, one embodiment will be described in detail with reference to the drawings. In addition, in each drawing, identical or equivalent parts are assigned the same reference numerals, and overlapping descriptions are omitted.

[Configuration of laser processing equipment]

As shown in FIG. 1, the laser processing device 1 includes a plurality of moving mechanisms 5 and 6, a support portion 7, and a pair of laser processing heads (a first laser processing head and a second laser processing head). heads) (10A, 10B), a light source unit (8), and a control unit (9). Hereinafter, the first direction is referred to as the X direction, the second direction perpendicular to the first direction is referred to as the Y direction, and the third direction perpendicular to the first and second directions is referred to as the Z direction. In this embodiment, the X direction and Y direction are horizontal directions, and the Z direction is a vertical direction.

The moving mechanism 5 has a fixing part 51, a moving part 53, and a mounting part 55. The fixing portion 51 is mounted on the device frame 1a. The moving part 53 is mounted on a rail provided on the fixed part 51 and can move along the Y direction. The mounting portion 55 is mounted on 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 (a first moving part, a second moving part) 63, 64, and a pair of mounting parts (a first mounting part, a second mounting part). It has (65, 66). The fixing portion 61 is mounted on the device frame 1a. Each of the pair of moving parts 63 and 64 is mounted on a rail provided on the fixed part 61, and each can move independently along the Y direction. The mounting portion 65 is mounted on a rail provided on the moving portion 63 and can move along the Z direction. The mounting portion 66 is mounted on 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, respectively.

The support portion 7 is mounted on a rotation shaft provided in the mounting portion 55 of the moving mechanism 5 and can rotate with the axis parallel to the Z direction as the center line. That is, the support portion 7 can move along each of the X and Y directions, and can rotate with the axis parallel to the Z direction as the center line. The support portion 7 supports the object 100 along the X and Y directions. The object 100 is, for example, a wafer.

1 and 2, the laser processing head 10A (for example, the first laser processing head) is mounted on the mounting portion 65 of the moving mechanism 6. The laser processing head 10A is for irradiating a laser beam (first laser beam) L1 to the object 100 supported by the support part 7 in a state facing the support part 7 in the Z direction. The laser processing head 10B (for example, the second laser processing head) is mounted on the mounting portion 66 of the moving mechanism 6. The laser processing head 10B is for irradiating a laser beam (second laser beam) L2 to the object 100 supported by the support part 7 in a state facing the support part 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 emission portion 81a of the light source 81 and is 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 emission 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 part of the laser processing device 1 (a plurality of moving mechanisms 5 and 6, a pair of laser processing heads 10A and 10B, and a light source unit 8, etc.). Control. The control unit 9 is configured as a computer device including a processor, memory, storage, and communication devices. In the control unit 9, software (program) read into memory, etc. is executed by a processor, and reading and writing of data from memory and storage, and communication by communication devices are controlled by the processor. Thereby, the control unit 9 realizes various functions.

An example of processing using the laser processing device 1 configured as above will be described. An example of this processing is an example of forming a modified area inside the object 100 along each of a plurality of lines set in a grid shape in order to cut the object 100, which is a wafer, into a plurality of chips.

First, the moving mechanism 5 moves the support portion (7) supporting the object 100 along each of the 7) Move it. Next, the moving mechanism 5 rotates the support portion 7 with the axis parallel to the Z direction as the center line so that a plurality of lines extending in one direction from the object 100 follow the X direction.

Next, the moving mechanism 6 moves the laser processing head 10A along the Y direction so that the condensing point of the laser light 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 condensing point of the laser light L2 is located on another line extending in one direction. Next, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the condensing 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 condensing point of the laser beam L2 is located inside the object 100.

Next, the light source 81 outputs the laser light L1, and the laser processing head 10A irradiates the laser light L1 to the object 100, and the light source 82 outputs the laser light L2. Thus, the laser processing head 10B irradiates the laser light L2 to the object 100. At the same time, the converging point of the laser light L1 moves relatively along one line extending in one direction (the laser light L1 is scanned), and the laser light L2 moves along another line extending in one direction. The moving mechanism 5 moves the support portion 7 along the X direction so that the converging point moves relatively (so that the laser beam L2 is scanned). In this way, the laser processing device 1 forms a modified region inside the object 100 along each of a plurality of lines extending in one direction from the object 100.

Next, the moving mechanism 5 rotates the support portion 7 with the axis parallel to the Z direction as the center line so that a plurality of lines extending from the object 100 in one direction and the other direction orthogonal to the other direction follow the X direction. .

Next, the moving mechanism 6 moves the laser processing head 10A along the Y direction so that the condensing 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 condensing point of the laser light L2 is located on another line extending in the other direction. Next, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the condensing 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 condensing point of the laser beam L2 is located inside the object 100.

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

In addition, in an example of the above-described processing, the light source 81 outputs a laser light L1 that has transparency to the object 100 by, for example, a pulse oscillation method, and the light source 82 outputs, for example, a laser light L1 that has transparency to the object 100. For example, laser light L2 having transparency to the object 100 is output by a pulse oscillation method. When such laser light is concentrated inside the object 100, the laser light is particularly absorbed in a portion corresponding to the convergence point of the laser light, and a modified area is formed inside the object 100. The modified region is a region in which density, refractive index, mechanical strength, and other physical properties are different from the surrounding unmodified region. Examples of modified regions include melt processing regions, crack regions, dielectric breakdown regions, and refractive index change regions.

When the laser light output by the pulse oscillation method is irradiated to the object 100 and the converging point of the laser light is relatively moved along the line set on the object 100, a plurality of modified spots are formed in a row along the line. do. One modified spot is formed by irradiation of one pulse of laser light. A row of reformed areas is a set of a plurality of reformed spots arranged in a 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 converging point of the laser light with respect to the object 100 and the repetition frequency of the laser light.

［Configuration of the laser processing head］

As shown in FIGS. 3 and 4, the laser processing head 10A includes a case 11 (for example, a first case), an incident portion 12, an adjustment portion 13, and a light converging portion 14. ) (for example, a first light condensing part).

The case 11 has a first wall 21 and a second wall 22, a third wall 23 and a fourth wall 24, and a fifth wall 25 and a sixth wall 26. there is. 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. Additionally, the distance between the first wall portion 21 and the second wall portion 22 may be the same as the distance between the fifth wall portion 25 and the sixth wall portion 26, or the distance between the fifth wall portion 25 and the sixth wall portion 26 may be the same as the distance between the fifth wall portion 25 and the sixth wall portion 26. It is okay to be larger than the distance from (26).

In the laser processing head 10A, the first wall portion 21 is located on the side of the fixed portion 61 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 side of the mounting portion 65 of the moving mechanism 6, and the fourth wall portion 24 is located on the side of the laser processing head 10B on the opposite side from the mounting portion 65 (Fig. 2). That is, the fourth wall portion 24 is an opposing wall portion that opposes the case (second case) of the laser processing head 10B along the Y direction. The fifth wall portion 25 is located on the opposite side to the support portion 7, and the sixth wall portion 26 is located on the support portion 7 side.

The case 11 is configured so that the case 11 is mounted on the mounting portion 65 with the third wall portion 23 disposed 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 mounted on a rail provided on the moving part 63 (see FIG. 2). The mounting plate 65b stands on the end of the base plate 65a on the laser processing head 10B side. It is provided (see Figure 2). The case 11 is provided with a mounting portion 65 by screwing the bolt 28 to the mounting plate 65b via the base 27 while the third wall portion 23 is in contact with the mounting plate 65b. ) is installed. The base 27 is provided on each of the first wall portion 21 and the second wall portion 22. The case 11 is removable from the mounting portion 65.

The entrance portion 12 is mounted on the fifth wall portion 25. The incident unit 12 makes the laser light L1 enter the case 11. The incident portion 12 is biased toward the second wall portion 22 (one wall portion) in the X direction, and toward the fourth wall portion 24 in the Y direction. That is, the distance between the incident portion 12 and the second wall 22 in the X direction is smaller than the distance between the incident portion 12 and the first wall 21 in the ) and the fourth wall portion 24 is smaller than the distance between the incident portion 12 and the third wall portion 23 in the X direction.

The entrance portion 12 is configured so that the connection end 2a of the optical fiber 2 can be connected. At the connection end 2a of the optical fiber 2, a collimator lens is provided for collimating the laser light L1 emitted from the exit end of the fiber, and an isolator is provided to suppress the return light. There is not. The isolator is provided in the middle of the fiber closer to the light source 81 than the connection end 2a. As a result, miniaturization of the connection end portion 2a and, by extension, miniaturization of the entrance portion 12 are achieved. Additionally, an isolator may be provided at the connection end 2a of the optical fiber 2.

The adjustment unit 13 is disposed within the case 11. The adjustment unit 13 adjusts the laser light L1 incident from the incident unit 12. Each component of the adjustment unit 13 is mounted on the optical base 29 provided in the case 11. The optical base 29 is mounted on the case 11 so as to divide the area inside the case 11 into an area on the third wall 23 side and an area on the fourth wall 24 side. The optical base 29 is integrated with the case 11. Each component of the adjustment unit 13 is mounted on 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 condensing portion 14 is disposed on the sixth wall portion 26 . Specifically, the light condensing portion 14 is disposed on the sixth wall portion 26 while being inserted into the hole 26a formed in the sixth wall portion 26 . The light condensing unit 14 condenses the laser light L1 adjusted by the adjusting unit 13 and emits it out of the case 11. The light condensing portion 14 is biased toward the second wall portion 22 (one wall portion) in the X direction, and toward the fourth wall portion 24 in the Y direction. That is, the light condensing portion 14 is disposed with a bias toward the fourth wall portion (opposite wall portion) 24 of the case 11 when viewed from the Z direction. That is, the distance between the light collecting part 14 and the second wall 22 in the X direction is smaller than the distance between the light collecting part 14 and the first wall 21 in the ) and the fourth wall portion 24 is smaller than the distance between the light condensing portion 14 and the third wall portion 23 in the X direction.

As shown in FIG. 5 , the adjustment unit 13 has an attenuator 31, a beam expander 32, and a mirror 33. The incident unit 12 and the attenuator 31, beam expander 32, and mirror 33 of the adjustment 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 portion 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 has been adjusted by the attenuator 31. The mirror 33 reflects the laser light L1 whose diameter has been expanded by the beam expander 32.

The adjustment unit 13 further includes a reflective spatial light modulator 34 and an imaging optical system 35. The reflective spatial light modulator 34 and imaging optical system 35 of the adjustment unit 13, and the light 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 from the mirror 33. The reflective spatial light modulator 34 is, for example, a spatial light modulator (SLM: Spatial Light Modulator) of reflective liquid crystal (LCOS: Liquid Crystal on Silicon). The imaging optical system 35 constitutes a bilateral telecentric optical system in which the reflection surface 34a of the reflective spatial light modulator 34 and the entrance pupil surface 14a of the light collection unit 14 are in an imaging relationship. The imaging optical system 35 is comprised of three or more lenses.

The straight lines A1 and A2 are located on a plane perpendicular to the Y direction. The straight line A1 is located on the second wall 22 side (one wall side) with respect to the straight line A2. In the laser processing head 10A, the laser light L1 enters the case 11 from the incident unit 12 and travels along a straight line A1, and passes through the mirror 33 and the reflective spatial light modulator 34. After being reflected sequentially, it travels along the straight line A2 and is emitted from the light collection unit 14 to the outside of the case 11. Additionally, the order of arrangement of the attenuator 31 and the beam expander 32 may be reversed. Additionally, the attenuator 31 may be disposed between the mirror 33 and the reflective spatial light modulator 34. Additionally, the adjustment unit 13 may have other optical components (for example, a steering mirror disposed before the beam expander 32, etc.).

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 disposed between the imaging optical system 35 and the light condensing unit 14 on the straight line A2. That is, the dichroic mirror 15 is disposed within the case 11 between the adjustment unit 13 and the light condensing unit 14. The dichroic mirror 15 is mounted on the optical base 29 on the fourth wall 24 side. The dichroic mirror 15 transmits the laser light L1. From the viewpoint of suppressing astigmatism, the dichroic mirror 15 can be, for example, shaped like a cube or shaped like two plates arranged in a torsional relationship.

The measurement unit 16 is disposed within the case 11 on the first wall 21 side (opposite to one wall side) with respect to the adjustment unit 13. The measurement unit 16 is mounted on the optical base 29 on the fourth wall 24 side. The measurement unit 16 outputs measurement light L10 to measure the distance between the surface of the object 100 (for example, the surface on the side where the laser light L1 is incident) and the light collection unit 14. , the measurement light L10 reflected from the surface of the object 100 is detected through the light condenser 14. That is, the measurement light L10 output from the measurement unit 16 is irradiated onto the surface of the object 100 through the light condenser 14, and the measurement light L10 reflected from the surface of the object 100 is, It is detected in the measurement unit 16 via the light condensing unit 14.

More specifically, the measurement light L10 output from the measurement unit 16 is connected to the beam splitter 20 and the dichroic mirror 15 mounted on the optical base 29 on the fourth wall 24 side. It is sequentially reflected and emitted from the light collection unit 14 to the outside of the case 11. The measurement light L10 reflected from the surface of the object 100 enters the case 11 from the light collection unit 14 and is sequentially reflected by the dichroic mirror 15 and the beam splitter 20, and is sequentially reflected by the measurement unit 10. It is incident on (16) and detected by the measuring unit (16).

The observation unit 17 is disposed within the case 11 on the first wall 21 side (opposite to one wall side) with respect to the adjustment unit 13. The observation unit 17 is mounted on the optical base 29 on the fourth wall 24 side. The observation unit 17 outputs observation light L20 for observing the surface of the object 100 (e.g., the surface on the side where the laser light L1 is incident) and passes through the light converging unit 14, Observation light L20 reflected from the surface of the object 100 is detected. That is, the observation light L20 output from the observation unit 17 is irradiated onto the surface of the object 100 through the light condenser 14, and the observation light L20 reflected from the surface of the object 100 is collected. It is detected in the observation unit 17 via the light emitter 14.

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 exits the case 11 from the light condenser 14. do. The observation light L20 reflected from the surface of the object 100 enters the case 11 from the light collection unit 14, is reflected by the dichroic mirror 15, and passes through the beam splitter 20 to the observation unit ( 17) and is detected in the observation unit 17. In addition, the wavelengths of the laser light L1, the measurement light L10, and the observation light L20 are different from each other (at least the center wavelengths of each are offset from each other).

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

The circuit portion 19 is disposed within the case 11 on the third wall portion 23 side with respect to the optical base 29. That is, the circuit portion 19 is disposed within the case 11 on the third wall portion 23 side with respect to the adjustment portion 13, the measurement portion 16, and the observation portion 17. The circuit portion 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 is configured to maintain a constant distance between the surface of the object 100 and the light collecting unit 14 based on the signal output from the measuring unit 16 (i.e., the distance between the surface of the object 100 and the light collecting unit 14 is maintained constant). The driver 18 is controlled so that the distance between the surface and the converging point of the laser light (L1) is maintained constant. Additionally, the case 11 is provided with a connector (not shown) to which wiring is connected to electrically connect the circuit section 19 to the control section 9 (see FIG. 1), etc.

Like the laser processing head 10A, the laser processing head 10B includes a case 11 (for example, a second case), an incident part 12, an adjustment part 13, and a light converging part (for example, It is provided with a second light condensing unit (14), a dichroic mirror (15), a measuring unit (16), an observation unit (17), a driving unit (18), and a circuit unit (19). However, as shown in FIG. 2, each configuration of the laser processing head 10B is a virtual plane that passes through the midpoint between the pair of mounting portions 65 and 66 and is perpendicular to the Y direction. It is arranged so as to have a plane symmetry relationship with each configuration of (10A) (this is an example as will be described later).

For example, in the case 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 located on the third wall portion 23. 5 It is mounted on the mounting portion 65 so as to be located on the support portion 7 side with respect to the wall portion 25. In contrast, in the case 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 located on the third wall portion 23. 5 It is mounted on the mounting portion 66 so as to be located on the support portion 7 side with respect to the wall portion 25. That is, also in the laser processing head 10B, the fourth wall portion 24 is an opposing wall portion that opposes the case of the laser processing head 10A along the Y direction. Also, in the laser processing head 10B, the light condensing portion 14 is disposed with a bias toward the fourth wall portion (opposite wall portion) 24 of the case 11 when viewed from the Z direction.

The case 11 of the laser processing head 10B is configured so that the case 11 is mounted on the mounting portion 66 with the third wall portion 23 disposed 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 mounted on a rail provided on the moving part 63. The mounting plate 66b is provided standing at the end of the base plate 66a on the laser processing head 10A side. The case 11 of the laser processing head 10B is mounted on the mounting portion 66 with the third wall portion 23 in contact with the mounting plate 66b. The case 11 of the laser processing head 10B is detachable from the mounting portion 66.

[Action 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 case 11, the case 11 can be miniaturized. Moreover, in the case 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 is disposed on the sixth wall portion 26. The light condensing portion 14 is biased toward the fourth wall portion 24 in the Y direction. As a result, when moving the case 11 along the direction perpendicular to the optical axis of the light converging portion 14, for example, another configuration (for example, a laser processing head) is placed on the fourth wall portion 24 side. Even if 10B)) was present, the light concentrator 14 could be brought close to the other configuration. Accordingly, the laser processing head 10A may be suitable for moving the light collecting portion 14 along a direction perpendicular to its optical axis.

Moreover, in the laser processing head 10A, the incident part 12 is provided in the 5th wall part 25, and is biased toward the 4th wall part 24 side in the Y direction. As a result, the area within the case 11 can be effectively used, such as by arranging another component (e.g., the circuit section 19) in the area on the third wall 23 side with respect to the adjustment section 13. You can.

Moreover, in the laser processing head 10A, the light condensing part 14 is biased toward the second wall part 22 in the X direction. As a result, when the case 11 is moved along the direction perpendicular to the optical axis of the light converging portion 14, for example, even if a different configuration exists on the second wall portion 22 side, the other configuration The light condensing part 14 can be brought closer.

Moreover, in the laser processing head 10A, the incident part 12 is provided in the 5th wall part 25, and is biased toward the 2nd wall part 22 in the X direction. As a result, other components (for example, the measurement unit 16 and the observation unit 17) are arranged in the area within the case 11 on the side of the first wall 21 with respect to the adjustment unit 13, etc. The area can be used effectively.

Moreover, in the laser processing head 10A, the measurement unit 16 and the observation unit 17 are arranged in an area on the side of the first wall 21 with respect to the adjustment unit 13 among the areas within the case 11, and the circuit section (19) is disposed on the third wall portion 23 side with respect to the adjusting portion 13 in the area within the case 11, and the dichroic mirror 15 is positioned between the adjusting portion 13 and the adjusting portion 11 within the case 11. It is arranged between the light condensing part 14. As a result, the area within the case 11 can be effectively used. Furthermore, in the laser processing apparatus 1, processing is possible based on the measurement result of the distance between the surface of the object 100 and the light converging portion 14. Additionally, in the laser processing device 1, processing based on the observation results of the surface of the object 100 is possible.

Moreover, in the laser processing head 10A, the circuit unit 19 controls the drive unit 18 based on the signal output from the measurement unit 16. As a result, the position of the converging point of the laser light L1 can be adjusted based on the measurement result of the distance between the surface of the object 100 and the light condensing portion 14.

In addition, in the laser processing head 10A, the incident unit 12, and the attenuator 31, beam expander 32, and mirror 33 of the adjustment unit 13 form a straight line A1 extending along the Z direction. It is disposed on a straight line A2 in which the reflective spatial light modulator 34 of the adjustment unit 13, the imaging optical system 35, and the light condensing unit 14, and the condensing unit 14 extend along the Z direction. It is placed on the table. As a result, the adjustment 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.

Moreover, in the laser processing head 10A, the straight line A1 is located on the second wall portion 22 side with respect to the straight line A2. As a result, in the area within the case 11 on the side of the first wall 21 with respect to the adjustment unit 13, another optical system (for example, the measurement unit 16 and the observation unit) using the light condensing unit 14 is used. 17)), the degree of freedom in configuring other optical systems can be improved.

The above actions and effects are equally exhibited by the laser processing head 10B.

[Variation example of laser processing head]

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

In addition, the light guide of the laser light L1 from the emission part 81a of the light source unit 8 to the incident part 12 of the laser processing head 10A, and the emission part 82a of the light source unit 8 ), at least one of the light guides of the laser light L2 from ) to the incident portion 12 of the laser processing head 10B may be performed by a mirror. Fig. 7 is a front view of a portion of the laser processing device 1 in which the laser light L1 is guided by a mirror. In the configuration shown in FIG. 7, the mirror 3 that reflects the laser light L1 faces the emitting portion 81a of the light source unit 8 in the Y direction and faces the laser processing head 10A in the Z direction. It is mounted on the moving part 63 of the moving mechanism 6 so as to face the entrance part 12.

In the configuration shown in Fig. 7, even if the moving portion 63 of the moving mechanism 6 is moved along the Y direction, the mirror 3 faces the emitting portion 81a of the light source unit 8 in the Y direction. is maintained. Moreover, 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 is maintained in the Z direction. 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 is surely incident on the incident portion 12 of the laser processing head 10A. You can do it. In addition, a light source such as a high-output long/short pulse laser that is difficult to guide light through the optical fiber 2 can also be used.

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

Additionally, the light source unit 8 may have one light source. In that case, the light source unit 8 may be configured to emit a part of the laser light output from one light source from the emitter 81a and to emit the remainder of the laser light from the emitter 82a.

［About the operation of laser processing equipment, etc.］

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

Additionally, the laser processing device 1 is equipped with a pair of alignment cameras (AC) with different magnifications. The alignment camera AC is mounted on the mounting portion 66 together with the laser processing head 10B. The alignment camera AC captures, for example, a device pattern using light passing through the object 100. The image thus obtained is used for alignment of the irradiation position of the laser beams L1 and L2 with respect to the object 100.

Moreover, 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, mounting portions 65 and 66 are provided on their second wall portions 22. And the mounting parts 65 and 66 are collectively mounted on the extension member (moving part) EM via the moving parts 63 and 64. The extension member EM is mounted on the fixing portion 61. The extension member EM is mounted on a rail provided on the fixing portion 61 and can move along the Y direction. That is, here, while the laser processing head 10A and the laser processing head 10B can move independently of each other in the Z direction, they are configured to move collectively in the Y direction.

The object 100 is provided with a plurality of lines C extending along the X direction and arranged along the Y direction. Line (C) is an imaginary line, but it may also be an actual drawn line. Additionally, on the object 100, a plurality of lines extending along the Y direction and arranged along the

The laser processing device 1 performs laser processing along each line C under the control of the control unit 9. According to the laser processing apparatus 1, various types of laser processing are possible, but here, laser processing in which a modified region is formed at least inside the object 100 is exemplified. That is, the laser processing heads 10A and 10B are used here to form a modified region by irradiating the laser light L1 and L2 to at least the inside of the object 100 supported on the support portion 7.

Here, the control unit 9 controls the movement of the support part 7, the mounting part 65, the mounting part 66, and the extension member EM, and the movement of the support part 7, the mounting part 65, the mounting part 66, and the extension member EM, and Controls the irradiation of laser light (L1, L2). In the laser processing device 1, the control unit 9 executes the first processing and the second processing. The first processing includes a first scan process and a second scan process. The second processing includes a third scan process and a fourth scan process.

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

That the control unit 9 scans the laser light (L1, L2) in the X direction (or the opposite direction) means that the laser processing head (10A, 10B) is moved in the Y direction and the Z direction so that the condensing point of the laser light L1 and L2 is located at a position inside the object 100 on each line C. Then, in that state, the support portion 7 is moved in the is to move .

In particular, here, the control unit 9 executes the first scan process, the second scan process, and the third scan process and the fourth scan process so that they overlap at least part of the time. That is, the control unit 9 ensures that the state in which the laser light L1 is scanned and the state in which the laser light L2 is scanned are realized at least partially simultaneously. That is, the control unit 9 operates the laser processing head 10A and the laser processing head 10B in overlap. This clearly improves throughput compared to processing using a single laser processing head.

Next, the operation of the laser processing device 1 will be described in detail. 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, as shown in FIGS. 9 and 10, thereby (10A) and the laser processing head 10B are set in a first state in which they are arranged on one line C among the plurality of lines C. Here, as an example, one line C is a line C located at one end of the plurality of lines C in the second direction of the object 100. Additionally, in FIG. 9 , for the sake of explanation, the modified area M is shown as a solid line, but it is not necessary for the modified area M to actually be 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 needed to move the laser processing head 10A to the converging point P1 of the laser light L1. Position it at the first position in the Z direction. Moreover, in the first state, the control unit 9 moves the laser processing head 10B in the Z direction as needed to create a convergence point P2 of the laser light L2 from the laser processing head 10B. is placed at the second position in the Z direction. The second position is a position closer to the incident surface 100a of the laser beams L1 and L2 of the object 100 than the first position in the Z direction.

After setting the condensing points P1 and P2 as described above, the control unit 9 moves the support unit 7 in a direction opposite to the A first scan process for scanning the laser beam L2 from the laser processing head 10B in the 2 Execute the first machining process that executes the scan process. 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 controls the condensing point P2 of the laser light L2 from the laser processing head 10B to converge the laser light L1 from the laser processing head 10A. The first scan process and the second scan process are performed while setting the position at a distance L or more (distance L here) and away from the point P1 in the direction opposite to the X direction (X negative direction: downstream). Accordingly, the modified region M1 is formed ahead of the modified region M2 by a distance L in the X direction. In other words, the modified region M2 is formed to follow the modified region M1 by a distance L. As shown in FIG. 11, if this is done, the amount of crack growth due to the formation of the modified region M2 becomes sufficient.

When the laser processing for the one line C is completed, the control unit 9 performs laser processing for another line C adjacent to the one line C among the plurality of lines C. 2 Execute processing. That is, the control unit 9 first moves the laser processing heads 10A and 10B in the Y direction after the first processing, so that the laser processing heads 10A and the laser processing heads 10B perform a plurality of operations. It is in the second state arranged on the corresponding other line (C) of the line (C).

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

After setting the condensing points P1 and P2 as described above, the control unit 9 moves the support unit 7 in the X direction (opposite direction to the first processing) from the laser processing head 10A. A third scanning process of scanning the laser light L1 in the direction opposite to the X direction with respect to the other line C, and scanning the laser light L2 from the laser processing head 10B to the other line C A second machining process is performed in which a fourth scan process is performed to scan in the direction opposite to the X direction. As a result, modified regions M are formed inside the object 100 in each region corresponding to the first position and the second position.

Here, in the second processing, the control unit 9 controls the condensing point P1 of the laser light L1 from the laser processing head 10A to converge the laser light L2 from the laser processing head 10B. The third and fourth scan processes are performed while setting the position at a distance L or more (distance L here) in the X direction (upstream side) from the point P2. Accordingly, the modified region M2 is formed ahead of the modified region M1 by a distance L in the X direction. In other words, the modified region M1 is formed to follow the modified region M2 by a distance L. In this way, the amount of crack growth caused by forming the modified region M1 becomes sufficient.

The control unit 9 alternately and repeatedly executes the above-mentioned first processing and second processing (for all lines C) a number of times according to the number of lines C. As a result, modified regions M1 and M2 are formed for all lines C, and cracks extending from the modified regions M1 and M2 can be sufficiently developed. Thereafter, by rotating the support portion 7 as necessary, the line intersecting the line C can be set to follow the X direction, and the above operation can be repeated.

［Action and effect of laser processing equipment］

As described above, the laser processing device 1 is movable along the X direction, and includes a support portion 7 for supporting the object 100 along the It is arranged along and is provided with laser processing heads (10A, 10B) for forming a modified region (M) by irradiating laser light (L1, L2) to at least the inside of the object (100) supported on the support portion (7). . In addition, the laser processing device 1 is equipped with a laser processing head 10A and is equipped with a mounting portion 65 capable of moving along the Z direction, and a laser processing head 10B is mounted and is capable of moving along the Z direction. It is provided with a mounting portion 66 and an extension member EM that moves the mounting portions 65 and 66 along the Y direction. In addition, the laser processing device 1 moves the support portion 7, the extension member EM, the mounting portion 65, and the mounting portion 66, and the laser light L1 from the laser processing heads 10A and 10B. , and a control unit 9 that controls the irradiation of L2).

The object 100 is provided with a plurality of lines C extending along the X direction and arranged along the Y direction. The control unit 9 controls the laser light L1 from the laser processing head 10A in a first state in which the laser processing heads 10A and 10B are arranged on one line C among the plurality of lines C. A first scan process of scanning the laser light L1 from the laser processing head 10A in the , In the first state, the laser light L2 from the laser processing head 10B is positioned at the second position in the Z direction while the condensing point P2 of the laser light L2 from the laser processing head 10B is positioned at the second position in the Z direction. The first machining process is executed by executing the second scan process to scan one line in the X direction. The second position is a position closer to the incident surface 100a of the laser beams L1 and L2 of the object 100 than the first position in the Z direction. And, in the first processing, the control unit 9 sets the condensing point P2 of the laser light L2 from the laser processing head to the converging 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 setting the positions away from each other in the direction opposite to the X direction by a distance L or more.

In this laser processing device 1, the laser processing heads 10A and 10B can be arranged along the X direction. Then, the control unit 9 performs a first scan process using the laser processing head 10A and the laser processing head 10B in a first state in which the laser processing heads 10A and 10B are arranged on the line C. Execute the second scan process using . In the first scan process, the control unit 9 directs the laser light L1 in the Scan. In the second scan processing, the control unit 9 sets the condensing point P2 of the laser light L2 from the laser processing head 10B to the second position in the Z direction and sends the laser light ( Scan L2) in the X direction. As a result, two rows of modified regions M can be formed almost simultaneously within at least the interior of the object 100 using the two laser processing heads 10A and 10B for one line C.

Here, according to the present inventors' knowledge, when using one laser processing head, cracks extending from each modified region can be sufficiently advanced by performing multiple scans at different positions in the depth direction (Z direction) of the object. You can do it. However, in this case, improvement in throughput is not achieved. In contrast, when forming two rows of modified regions M inside the object 100 using two laser processing heads 10A and 10B, the laser from each laser processing head 10A and 10B If the converging points P1 and P2 of the light L1 and L2 are aligned with the X direction, it is difficult for a crack extending from the modified region M to develop.

In contrast, in this laser processing device 1, the condensing point P2 of the laser light L2 from the laser processing head 10B is the condensing point P2 of the laser light L1 from the laser processing head 10A. The first scan process and the second scan process are performed while positioning the objects in a direction opposite to the X direction by a distance L greater than (P1). According to this, the laser processing head 10B is scanned to follow by a distance L while forming the first row modified region M1 by scanning the laser light L1 from the preceding laser processing head 10A. By using the laser light L2 from , it is possible to sufficiently advance the crack while forming the second row modified region M2. Therefore, according to this laser processing device 1, throughput can be improved.

Moreover, in the laser processing apparatus 1, the control unit 9 controls the laser light L1 in a second state in which the laser processing heads 10A and 10B are arranged on different lines C after the first processing. A third scanning process of scanning the laser light L1 in a direction opposite to the A second processing process is performed in which a fourth scan process is performed in which the laser light L2 is scanned in a direction opposite to the X direction with respect to the line C while positioning the condensing point P2 at the first position. In the second processing, the control unit 9 sets the converging point P1 of the laser light L1 to a position further away from the converging point P2 of the laser beam L2 in the Execute 3 scan processing and fourth scan processing. For this reason, the position of the laser processing heads 10A, 10B in the Therefore, laser processing is preferably possible.

Moreover, in the laser processing apparatus 1, the control unit 9 alternately and repeatedly performs the first processing and the second processing as many times as the number of lines C is determined. For this reason, for example, laser processing along all lines C is possible by reciprocating motion of the support portion 7 along the X direction and sequential movement of the laser processing heads 10A, 10B in the Y direction. This becomes possible.

Additionally, in the laser processing device 1, the distance L is 300 μm. According to the present inventor's knowledge, by setting the distance L to 300 μm in this way, the crack can grow more sufficiently.

Furthermore, in the laser processing apparatus 1, the mounting parts 65 and 66 are collectively mounted on the extension member EM, and the extension member EM moves the mounting parts 65 and 66 in the Y direction. In this case, movement of the laser processing heads 10A, 10B in the Y direction becomes easy.

Moreover, in the laser processing device 1, the laser processing head 10A is provided in the case 11 and the sixth wall portion 26 on the support portion 7 side of the case 11, and the support portion 7 It has a light condenser 14 for concentrating the laser light L1 toward the object 100 supported on. In addition, the laser processing head 10B is also provided on the case 11 and the sixth wall portion 26 on the support portion 7 side of the case 11, and holds the object 100 supported on the support portion 7. It has a light condenser 14 for concentrating the laser light L2 toward the laser beam L2. In addition, the mounting portions 65 and 66 are respectively attached to the fourth wall portion 24 (opposite wall portion) and a different wall portion (here, the second wall portion 22) along the X direction in the case 11. It is equipped. And, the light condensing portions 14 are disposed with a bias toward the fourth wall portion 24 of the case 11 when viewed from the Z direction.

For this reason, 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 brought closer to each other in the Y direction. In addition, the light condensing portions 14 of each of the laser processing heads 10A and 10B are disposed with a bias toward the opposing fourth wall portion 24 of each case 11. For this reason, when the laser processing head 10A and the laser processing head 10B are brought close to each other, the distance between the light condensing portions 14 can be made smaller. As a result, the degree of freedom in setting the distance L is improved.

［Variation example］

The above embodiment exemplifies one embodiment of a laser processing device. Therefore, the laser processing device according to the present disclosure is not limited to the laser processing device 1 described above and may be arbitrarily modified.

12 to 15 are diagrams showing modifications of the mounting portion and the laser processing head. As shown in FIG. 12(a), the mounting portion 65 is provided on the first wall portion 21 of the case 11 of the laser processing head 10A, and the mounting portion 66 is attached to the laser processing head 10B. It may be provided on the first wall portion 21 of the case 11. In addition, as shown in FIG. 12(b), the mounting portion 65 is provided on the third wall portion 23 of the case 11 of the laser processing head 10A, and the mounting portion 66 is attached to the laser processing head. In the form provided on the third wall 23 of the case 11 of (10B), the positions of the moving parts 63 and 64 in the mounting parts 65 and 66 may be varied in the X direction. Furthermore, as shown in FIG. 12(c), the mounting portion 65 is provided on the third wall portion 23 of the case 11 of the laser processing head 10A, and the mounting portion 66 is attached to the laser processing head. In the form provided on the third wall portion 23 of the case 11 of (10B), the Y-direction positions of the moving portions 63 and 64 in the mounting portions 65 and 66 may be changed.

In addition, as shown in FIG. 13(a), the mounting portion 65 is provided on the fifth wall portion 25 of the case 11 of the laser processing head 10A, and the mounting portion 66 is attached to the laser processing head ( It may be provided on the fifth wall portion 25 of the case 11 of 10B). In addition, as shown in FIG. 13(b), the mounting portion 65 is provided on the sixth wall portion 26 of the case 11 of the laser processing head 10A, and the mounting portion 66 is attached to the laser processing head ( It may be provided on the sixth wall portion 26 of the case 11 of 10B). As described above, the mounting portions 65 and 66 may be mounted on a wall portion different from the fourth wall portion 24 that opposes each other along the X direction. Furthermore, as shown in (c) of FIG. 13, a light condensing portion 14 is provided at the center of the case 11 in the Y direction while expanding the gap between the first wall portion 21 and the second wall portion 22. It's okay to prepare it.

In addition, as in the above example, in the laser processing device 1, it is not necessary to use the laser processing head 10A and the laser processing head 10B as a pair of laser processing heads. That is, in the laser processing device 1, as shown in FIG. 14, a pair (one type) of laser processing heads 10A is used, or as shown in FIG. 15, a pair (the other one) is used. type) can be used or a laser processing head (10B) can be used. In these cases, with respect to one laser processing head 10A, 10B, the other laser processing head 10A, 10B is rotated 180° around the Z-axis direction, and the The positions of the centers of directions are arranged to coincide. In these cases, there is no need to prepare two types of laser processing heads. In addition, even in these cases, as shown in each drawing of FIG. 14 and FIG. 15, the mounting portions 65 and 66 are provided on the first wall portion 21 or the second wall portion 22, or on the third wall portion. It is okay to prepare it in (23).

In addition, in the above example, the converging 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, and the control unit 9 mechanically performs the laser processing. An example was given of moving the heads (10A, 10B) in the Z direction. However, in the laser processing device 1, the control unit 9 controls the adjustment unit 13 (e.g., the reflective spatial light modulator 34) to optically adjust the condensing points P1 and P2 to Z Even a configuration that moves it in one direction is okay.

In addition, in the above example, as an example of a moving part that moves at least one of the mounting parts 65, 66 and the support part 7 along the Y direction, an extension member EM on which the mounting parts 65, 66 are mounted together is used. heard. However, the moving part 53 of the moving mechanism 5 that moves the support part 7 in the Y direction may be used.

In addition, the control unit 9 operates at different wavelengths and at condensing positions in the Z direction by the laser light L1 from the laser processing head 10A and the laser light L2 from the laser processing head 10B. , it is okay to perform processing (multi-wavelength processing) to process the object 100. Multi-wavelength processing is, for example, when processing a wafer made by bonding silicon (Si) and glass (case 1), or when part of the laser light (L1, L2) incident from the back side is absorbed by the device. It can be used when processing wafers that may cause damage to the circuit (second case).

In the first case, processing is performed from the glass side because both light with a wavelength for processing silicon (e.g., 1064 nm) and light with a wavelength for processing glass (e.g., 532 nm) need to reach the target material. . The focusing position of the laser light L1 from the laser processing head 10A is aligned beyond the glass into the silicon, and the focusing position of the laser light L2 from the laser processing head 10B is aligned within the glass, and processing is performed with the corresponding wavelength. Conduct. In order to process a wafer in which two different types of substrates are bonded in this way through multi-wavelength processing, the wavelength for processing the lower substrate among the wavelengths must be a wavelength that transmits the upper substrate. Here, since multi-wavelength processing is performed using a pair of laser processing heads 10A and 10B, throughput is improved.

Meanwhile, in the second case, the condensing position of the laser beam L1 from the laser processing head 10A is set near the device, and the condensing position of the laser beam L2 from the laser processing head 10B is set near the device. Set it to a location away from The wavelength of the laser light (L1) is set to a wavelength that is more absorbed by the substrate (e.g., 1064 nm) to reduce leakage light to the device side, and the wavelength of the laser light (L2) is set to a wavelength that is more absorbable by the substrate, even if some leakage light occurs. , it can be set to a longer wavelength (for example, 1342 nm) than the wavelength of the laser light L1, which is more suitable for processing the substrate.

[Industrial applicability]

A laser processing device capable of improving throughput is provided.

1 - Laser processing device
7 - support
9 - Control unit
10A - Laser processing head (first laser processing head)
10B - Laser processing head (second laser processing head)
65 - Mounting part (first mounting part)
66 - Mounting part (second mounting part)
100 - object
C - line
L1, L2 - Laser light
P1, P2 - concentrating point

Claims (5)

a support portion capable of moving 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 arranged along the first direction and configured to form a modified region by irradiating laser light to at least the inside of the object supported on the support;
a first mounting portion on which the first laser processing head is mounted and capable of moving along a third direction intersecting the first direction and the second direction;
a second mounting portion on which the second laser processing head is mounted and capable of moving along the third direction;
a moving part that moves at least one of the first mounting part, the second mounting part, or the support part along the second direction;
A control unit that controls movement of the support unit, the moving unit, the first mounting unit, and the second mounting unit, and the irradiation of the laser light from the first laser processing head and the second laser processing head,
A plurality of lines extending along the first direction and arranged along the second direction are set on the object,
The control unit,
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, the convergence point of the laser light from the first laser processing head is located in the third direction. A first scan process of scanning the laser light from the first laser processing head in the first direction with respect to the one line while positioning the laser processing head at a first position,
In the first state, the laser light from the second laser processing head is directed to the one line while positioning the converging point of the laser light from the second laser processing head at the second position in the third direction. executing a first machining process that performs a second scan process for scanning in the first direction,
The second position is a position closer to the incident surface of the laser beam of the object than the first position with respect to the third direction,
In the first processing, the control unit sets the converging point of the laser beam from the second laser processing head in a direction opposite to the first direction at a distance L or more than the converging point of the laser beam from the first laser processing head. A laser processing device that performs the first scan process and the second scan process while maintaining the positions spaced apart from each other. In claim 1,
The control unit, after the first processing, in a second state in which the first laser processing head and the second laser processing head are arranged on another line adjacent to the one line among the plurality of lines, 1 A third scan process of scanning the laser light from the first laser processing head in a direction opposite to the first direction with respect to the line while positioning the converging point of the laser light from the laser processing head at the second position; ,
In the second state, the laser light from the second laser processing head is positioned in the first position in the opposite direction of the first direction with respect to the other line. Executing a second machining process that executes a fourth scan process that scans in the direction,
In the second processing, the control unit separates the converging point of the laser beam from the first laser processing head in the first direction by a distance L or more from the converging point of the laser beam from the second laser processing head. A laser processing device that performs the third scan process and the fourth scan process while positioning. In claim 2,
The control unit is a laser processing device that alternately and repeatedly performs the first processing and the second processing a number of times according to the number of lines. The method according to any one of claims 1 to 3,
A laser processing device where the distance L is 300 μm. The method according to any one of claims 1 to 3,
The first mounting part and the second mounting part are collectively mounted on the moving part,
The moving unit moves the first mounting unit and the second mounting unit in the second direction.

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