JP7219590B2 - Laser processing equipment - Google Patents

Description

The present invention relates to a laser processing apparatus.

Patent Literature 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 a laser beam. In the laser processing apparatus described in Patent Document 1, a laser irradiation mechanism having a condenser lens is fixed to a base, and movement of the workpiece along the direction perpendicular to the optical axis of the condenser lens is controlled by the holding mechanism. be implemented.

Japanese Patent No. 5456510

By the way, in order to improve the throughput of the laser processing apparatus as described above, it is conceivable, for example, to increase the moving speed of the workpiece by the holding mechanism. However, even if an attempt is made to increase the movement speed of the work, the acceleration time required for the movement of the work to reach uniform movement at the target speed also increases. For this reason, it is difficult to improve the throughput beyond a certain level by increasing the moving speed of the workpiece. Thus, in the above technical field, an improvement in throughput is desired. On the other hand, there is also a demand for non-destructive confirmation of the success or failure of laser processing.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a laser processing apparatus capable of non-destructively confirming the success or failure of laser processing while improving throughput.

A laser processing apparatus according to the present invention includes: a support section that is movable along a first direction and supports an object along the first direction and a second direction that intersects the first direction; A first laser processing head and a second laser processing head for irradiating a laser beam to an object supported by a support portion, and a first laser processing head are attached so as to face each other along the A first mounting portion movable along each of a third direction and a second direction intersecting the first direction and the second direction, and a second laser processing head are mounted, and the second direction and the third direction are mounted. and an imaging unit attached to the first mounting portion for capturing an image of an object using light passing through the object.

In this apparatus, a first laser processing head and a second laser processing head are arranged so as to face each other on a support that supports an object. The first laser processing head and the second laser processing head are independently movable in two mutually intersecting directions via the first mounting portion and the second mounting portion, respectively. Therefore, it is possible to perform laser processing by scanning laser beams independently of each other at two locations on the object. Therefore, throughput can be improved.

Further, an image pickup unit that picks up an image of an object using light that passes through the object is further attached to the first attachment portion responsible for moving the first laser processing head. Therefore, for example, while laser processing is being performed by the second laser processing head, it is possible to image another part of the object with the imaging unit. Therefore, it is possible to check the state of laser processing in a non-destructive manner while suppressing a decrease in throughput. In other words, according to this device, it is possible to confirm the success or failure of laser processing in a non-destructive manner while improving the throughput.

The laser processing apparatus according to the present invention includes movements of a support portion, a first mounting portion, and a second mounting portion, irradiation of laser light from the first laser processing head and the second laser processing head, and movement of an object by an imaging unit. a plurality of lines extending in the first direction and arranged in the second direction are set on the object; and the control unit includes a plurality of A first scanning process of scanning the laser beam from the first laser processing head in the first direction with respect to one line of the lines, and a second laser processing head with respect to another line of the plurality of lines A second scanning process for scanning a laser beam in a first direction overlaps at least part of the time, and an object including a line that has been processed while only the second scanning process is being performed and an image capturing process of capturing an image of the area by the image capturing unit. By performing the first scan process and the second scan process in duplicate in this manner, the throughput can be improved. Moreover, at the timing when only the second scanning process is being performed, the imaging process can be performed by controlling the imaging unit movable together with the first laser processing head. Therefore, it is possible to confirm the success or failure of laser processing in a non-destructive manner while improving the throughput more reliably.

In the laser processing apparatus according to the present invention, the control unit determines whether or not the modified region and/or cracks are formed in the object in the region according to the regulations, based on the image obtained by the imaging process. Along with making a judgment, as a result of the judgment, if it is judged that the modified region and / or cracks are not formed according to the regulations, at least the auxiliary processing to scan the laser light along the line again may be executed. In this case, the auxiliary machining process compensates for the machining error.

In the laser processing apparatus according to the present invention, the control unit sequentially performs a first scan from a line located at one end of the object in the second direction among the plurality of lines toward a line inside the second direction. a main processing process of sequentially executing a second scan process from a line positioned at the other end of the object in the second direction among the plurality of lines toward lines inside the second direction while executing the process; may be executed. In this way, in the main processing, by executing the first scanning process and the second scanning process in order from the line of the symmetrical position of the object in the second direction, The waste of relative movement along one direction is eliminated, and the throughput is further improved.

In the laser processing apparatus according to the present invention, the control unit retracts the first laser processing head when the first laser processing head and the second laser processing head are closest in the second direction in the main processing. While continuing the second scanning process, the imaging process may be executed. In this case, it is possible to check the success or failure of laser processing in a non-destructive manner while improving the throughput by maximally utilizing the first laser processing head and the second laser processing head.

ADVANTAGE OF THE INVENTION According to this invention, the laser processing apparatus which can confirm the success or failure of laser processing nondestructively can be provided, improving a throughput.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view of the laser processing apparatus of one Embodiment. 2 is a front view of a portion of the laser processing apparatus shown in FIG. 1; FIG. FIG. 2 is a front view of a laser processing head of the laser processing apparatus shown in FIG. 1; 4 is a side view of the laser processing head shown in FIG. 3; FIG. 4 is a configuration diagram of an optical system of the laser processing head shown in FIG. 3; FIG. It is a block diagram of the optical system of the laser processing head of a modification. It is a partial front view of the laser processing apparatus of a modification. It is a typical top view which shows operation|movement of a laser processing apparatus. It is a typical top view which shows operation|movement of a laser processing apparatus. It is a typical top view which shows operation|movement of a laser processing apparatus. It is a typical top view which shows operation|movement of a laser processing apparatus. It is a typical top view which shows operation|movement of a laser processing apparatus. It is a typical 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 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.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations are omitted.
[Configuration of laser processing device]

As shown in FIG. 1, the laser processing apparatus 1 includes a plurality of moving mechanisms 5 and 6, a support portion 7, and a pair of laser processing heads (first laser processing head and second laser processing head) 10A and 10B. , 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 and Y directions are horizontal and the Z direction is vertical.

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

The support portion 7 is attached to a rotation shaft provided in the attachment portion 55 of the moving mechanism 5, and can rotate around an axis line parallel to the Z direction. That is, the support portion 7 can move along each of the X direction and the Y direction, and can rotate about an axis line parallel to the Z direction. The support section 7 supports the target object 100 along the X direction and the Y direction. 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. As shown in FIG. The laser processing head 10A is for irradiating the target object 100 supported by the support portion 7 with a laser beam (first laser beam) L1 while facing the support portion 7 in the Z direction. A laser processing head 10</b>B (for example, a 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 target object 100 supported by the support portion 7 with a laser beam (second laser beam) L2 while facing the support portion 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 beam 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. As shown in FIG. The light source 82 outputs laser light L2. The laser beam L2 is emitted from the emitting portion 82a of the light source 82 and guided to the laser processing head 10B by another optical fiber 2. As shown in FIG.

The controller 9 controls each part of the laser processing apparatus 1 (a plurality of moving mechanisms 5 and 6, a pair of laser processing heads 10A and 10B, a light source unit 8, and the like). The control unit 9 is configured as a computer device including a processor, memory, storage, communication device, and the like. In the control unit 9, the software (program) loaded into the memory or the like is executed by the processor, and the reading and writing of data in the memory and storage and the communication by the communication device are controlled by the processor. Thereby, the control part 9 implement|achieves 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 of forming modified regions 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. be.

First, the moving mechanism 5 moves the support part 7 along each of the X direction and the Y direction so that the support part 7 supporting the object 100 faces the pair of laser processing heads 10A and 10B in the Z direction. to move. Subsequently, the moving mechanism 5 rotates the support part 7 around an axis line parallel to the Z direction so that a plurality of lines extending in one direction on 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 focal point of the laser beam L1 is positioned 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 beam L2 is positioned on another line extending in one direction. Subsequently, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the focal point of the laser beam L1 is located inside the object 100. FIG. On the other hand, the movement 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. FIG.

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

Subsequently, the moving mechanism 5 rotates the support part 7 about an axis line parallel to the Z direction so that a plurality of lines extending in the other direction orthogonal to the one direction on 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 focal point of the laser beam L1 is positioned 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 focal point of the laser beam L2 is positioned on another line extending in the other direction. Subsequently, the moving mechanism 6 moves the laser processing head 10A along the Z direction so that the focal point of the laser beam L1 is located inside the object 100. FIG. On the other hand, the movement 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. FIG.

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

In the example of processing described above, the light source 81 outputs a laser beam L1 having transparency to the object 100 by, for example, a pulse oscillation method, and the light source 82 emits laser light L1 to the object 100 by, for example, a pulse oscillation method. A laser beam L2 having transparency to the laser beam is output. When such laser light is focused inside the object 100 , the laser light is particularly absorbed in a portion corresponding to the focal point of the laser light, and a modified region is formed inside the object 100 . A modified region is a region that differs in density, refractive index, mechanical strength, or other physical properties from the surrounding unmodified region. Modified regions include, for example, a melting process region, a crack region, a dielectric breakdown region, a refractive index change region, and the like.

When the object 100 is irradiated with the laser beam output by the pulse oscillation method, and the focal point of the laser beam is relatively moved along the line set on the object 100, a plurality of modified spots are formed into a line. are arranged in a row along the One modified spot is formed by one pulse of laser light irradiation. A row of modified regions is a set of a plurality of modified spots arranged in a row. Adjacent modified spots may be connected to each other or separated from each other depending on the relative moving speed of the focal 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 housing (e.g., first housing) 11, an incident section 12, an adjusting section 13, and a condensing section (e.g., first condensing section). 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 the distance between the fifth wall portion 25 and the sixth wall portion may be the same. It may be larger than the distance from the portion 26 .

In the laser processing head 10</b>A, the first wall portion 21 is positioned on the fixed portion 61 side of the moving mechanism 6 , and the second wall portion 22 is positioned on the opposite side of 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 portion 63 (see FIG. 2). The mounting plate 65b is erected at the end of the base plate 65a on the side of the laser processing head 10B (see FIG. 2). The housing 11 is attached to the mounting portion 65 by screwing the bolt 28 into the mounting plate 65b via the pedestal 27 while the third wall portion 23 is in contact with the mounting plate 65b. The pedestal 27 is provided on each of the first wall portion 21 and the second wall portion 22 . The housing 11 can be attached to and detached from the attachment portion 65 .

The incidence section 12 is attached to the fifth wall section 25 . The incident part 12 causes the laser beam L<b>1 to enter the housing 11 . The incident portion 12 is biased toward the second wall portion 22 (one wall portion) in the X direction, and biased toward the fourth wall portion 24 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 distance between the incident portion 12 and the fourth wall portion 24 in the Y direction is smaller. is smaller than the distance between the entrance 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 2a of the optical fiber 2 is provided with a collimator lens for collimating the laser light L1 emitted from the output end of the fiber, and is not provided with an isolator for suppressing return light. The isolator is provided in the middle of the fiber on the light source 81 side of the connection end 2a. Thereby, miniaturization of the connecting end portion 2a, and further miniaturization of the incident portion 12 is achieved. An isolator may be provided at the connection end portion 2a of the optical fiber 2. FIG.

The adjustment unit 13 is arranged inside the housing 11 . The adjuster 13 adjusts the laser beam L1 incident from the incident part 12 . Details of the adjustment unit 13 will be described later.

The condensing portion 14 is arranged on the sixth wall portion 26 . Specifically, the condensing portion 14 is arranged on the sixth wall portion 26 while being inserted through a hole 26 a formed in the sixth wall portion 26 . The light collecting unit 14 emits the laser light L1 adjusted by the adjusting unit 13 to the outside of the housing 11 while collecting the laser light L1. The condensing portion 14 is biased toward the second wall portion 22 (one wall portion) in the X direction, and biased toward the fourth wall portion 24 in the Y direction. In other words, the condensing section 14 is arranged so as to be biased toward the fourth wall section (opposing wall section) 24 of the housing 11 when viewed in the Z direction. That is, the distance between the condensing part 14 and the second wall part 22 in the X direction is smaller than the distance between the condensing part 14 and the first wall part 21 in the X direction, and the distance between the condensing part 14 and the fourth wall part 21 in the Y direction The distance to 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 adjustment section 13 has an attenuator 31 , a beam expander 32 and a mirror 33 . The incident section 12 and the attenuator 31, beam expander 32 and mirror 33 of the adjusting section 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 beam L1 incident from the incident portion 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 beam L1 whose diameter has been expanded by the beam expander 32 .

The adjusting section 13 further has 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 adjusting section 13, and the condensing section 14 are arranged on a straight line (second straight line) A2 extending along the Z direction. A 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 imaging optical system 35 constitutes a double-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 section 14 are in an imaging relationship. The imaging optical system 35 is composed of three or more lenses.

The straight lines A1 and A2 are positioned 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 portion 12, travels along the straight line A1, is reflected by the mirror 33 and the reflective spatial light modulator 34 in sequence, and then travels along the straight line A2. The light travels upward and exits from the housing 11 through the condensing section 14 . The order of arrangement of the attenuator 31 and the beam expander 32 may be reversed. Also, the attenuator 31 may be arranged between the mirror 33 and the reflective spatial light modulator 34 . Also, the adjustment unit 13 may have other optical components (for example, a steering mirror or the like arranged in front of the beam expander 32).

The laser processing head 10</b>A further includes a dichroic mirror 15 , a measuring section 16 , an observing section 17 , a driving section 18 and a circuit section 19 .

The dichroic mirror 15 is arranged between the imaging optical system 35 and the condenser 14 on the straight line A2. In other words, the dichroic mirror 15 is arranged inside the housing 11 between the adjusting section 13 and the condensing section 14 . The dichroic mirror 15 is attached to the optical base 29 on the fourth wall 24 side. The dichroic mirror 15 transmits the laser beam L1. From the viewpoint of suppressing astigmatism, the dichroic mirror 15 is preferably, for example, a cube type or two plate types arranged to have a twisted relationship.

The measurement unit 16 is arranged in the housing 11 on the first wall portion 21 side (the side opposite to the one wall portion side) with respect to the adjustment portion 13 . The measuring section 16 is attached to the optical base 29 on the fourth wall section 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 which the laser beam L1 is incident) and the light collecting unit 14, and outputs the measurement light L10 through the light collecting unit 14. , the measuring 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 irradiated onto the surface of the object 100 via the light condensing unit 14, and the measurement light L10 reflected by the surface of the object 100 is transmitted through the light condensing unit 14. 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 fourth wall 24 side, and is emitted from the light collection unit 14. The light is emitted outside the housing 11 . The measurement light L10 reflected by the surface of the object 100 enters the housing 11 from the light collecting unit 14, is sequentially reflected by the dichroic mirror 15 and the beam splitter 20, enters the measurement unit 16, and reaches the measurement unit 16. detected by

The observation unit 17 is arranged in the housing 11 on the first wall portion 21 side (the side opposite to the one wall portion side) with respect to the adjustment portion 13 . The observation section 17 is attached to the optical base 29 on the fourth wall section 24 side. The observation unit 17 outputs observation light L20 for observing the surface of the object 100 (for example, the surface on which the laser beam L1 is incident), which is reflected by the surface of the object 100 via the light collecting unit 14 . The observed light L20 is detected. That is, the observation light L20 output from the observation unit 17 is irradiated onto the surface of the object 100 via the light collecting unit 14, and the observation light L20 reflected by the surface of the object 100 is transmitted through the light collecting unit 14. is detected by the observation unit 17.

More specifically, the observation light L20 output from the observation unit 17 is transmitted through the beam splitter 20, reflected by the dichroic mirror 15, and emitted from the light collection unit 14 to the outside of the housing 11. FIG. The observation light L20 reflected by the surface of the object 100 enters the housing 11 from the light collecting unit 14, is reflected by the dichroic mirror 15, passes through the beam splitter 20, enters the observation unit 17, and enters the observation unit 17. 17 is detected. Note that the wavelengths of the laser light L1, the measurement light L10, and the observation light L20 are different from each other (at least their center wavelengths are shifted from each other).

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

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

Like the laser processing head 10A, the laser processing head 10B includes a housing (for example, a second housing) 11, an incident section 12, an adjusting section 13, a light collecting section (for example, a second light collecting section) 14, A dichroic mirror 15 , a measuring section 16 , an observing section 17 , a driving section 18 and a circuit section 19 are provided. However, each configuration of the laser processing head 10B is, as shown in FIG. (this is an example as will be described later).

For example, the housing 11 of the laser processing head 10A has the fourth wall portion 24 located on the laser processing head 10B side with respect to the third wall portion 23 and the sixth wall portion 26 supported from the fifth wall portion 25. It is attached to the attachment portion 65 so as to be positioned on the portion 7 side. On the other hand, 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 with respect to the fifth wall portion 25. It is attached to the attachment portion 66 so as to be positioned 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 condensing portion 14 is arranged 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 66 a is attached to rails provided on the moving portion 63 . The mounting plate 66b is erected at the end of the base plate 66a on the side of the laser processing head 10A. 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 is attachable to and detachable from the mounting portion 66 .
[Action and effect of laser processing head]

In the laser processing head 10A, since the light source for outputting the laser beam L1 is not provided inside the housing 11, the housing 11 can be made smaller. 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 assembly attached to the sixth wall portion 26 The light portion 14 is biased toward the fourth wall portion 24 in the Y direction. As a result, when the housing 11 is moved along the direction perpendicular to the optical axis of the light collecting unit 14, for example, if there is another configuration (for example, the laser processing head 10B) on the side of the fourth wall 24, Also, the condensing unit 14 can be brought closer to the other configuration. Therefore, the laser processing head 10A is suitable for moving the condensing section 14 along the direction perpendicular to its optical axis.

In addition, in the laser processing head 10A, the incident portion 12 is provided on the fifth wall portion 25 and is biased toward the fourth wall portion 24 in the Y direction. As a result, it is possible to effectively utilize the region by arranging other components (for example, the circuit section 19) in the region on the third wall portion 23 side with respect to the adjustment portion 13 in the region within the housing 11. can.

Further, in the laser processing head 10A, the condensing portion 14 is biased toward the second wall portion 22 in the X direction. As a result, when the housing 11 is moved along the direction perpendicular to the optical axis of the condensing section 14, for example, even if there is another configuration on the side of the second wall section 22, the other configuration is focused. The optical section 14 can be brought closer.

In addition, in the laser processing head 10A, the incident portion 12 is provided on the fifth wall portion 25, is biased toward the fourth wall portion 24 side in the Y direction, and is biased toward the second wall portion 22 side in the X direction. ing. As a result, it is possible to effectively utilize the region by arranging other components (for example, the circuit section 19) in the region on the third wall portion 23 side with respect to the adjustment portion 13 in the region within the housing 11. can. Furthermore, in the area inside the housing 11, the area on the first wall part 21 side with respect to the adjustment part 13 can be used effectively by arranging other components (for example, the measurement part 16 and the observation part 17). can do.

In the laser processing head 10A, the measurement unit 16 and the observation unit 17 are arranged in a region on the first wall 21 side with respect to the adjustment unit 13 in the region inside the housing 11, and the circuit unit 19 is The dichroic mirror 15 is arranged on the third wall portion 23 side with respect to the adjustment portion 13 in the area inside the housing 11 , and the dichroic mirror 15 is arranged between the adjustment portion 13 and the light collecting portion 14 in the housing 11 . ing. As a result, the area inside the housing 11 can be effectively used. Furthermore, in the laser processing apparatus 1, processing based on the measurement result of the distance between the surface of the object 100 and the condensing section 14 is possible. Moreover, in the laser processing apparatus 1, processing based on the observation result of the surface of the target object 100 becomes possible.

Further, in the laser processing head 10A, the circuit section 19 controls the driving section 18 based on the signal output from the measuring section 16. FIG. Thereby, 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 condensing section 14 .

In the laser processing head 10A, the incident portion 12 and the attenuator 31, the beam expander 32 and the mirror 33 of the adjustment portion 13 are arranged on a straight line A1 extending along the Z direction. are arranged on a straight line A2 extending along the Z direction. Thereby, the adjustment section 13 having 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 on the second wall portion 22 side with respect to the straight line A2. As a result, another optical system (for example, the measurement unit 16 and the observation unit 17) using the light collecting unit 14 is installed in the area on the first wall unit 21 side with respect to the adjustment unit 13 in the area inside the housing 11. When configured, the degree of freedom in configuration of the other optical system can be improved.

The actions and effects described above 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 condensing section 14 may be arranged on a straight line A extending along the Z direction. According to this, the adjustment part 13 can be configured compactly. In that case, the adjusting section 13 may not have the reflective spatial light modulator 34 and the imaging optical system 35 . Also, the adjustment unit 13 may have an attenuator 31 and a beam expander 32 . According to this, the adjustment section 13 having 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.

Also, the laser beam L1 is guided from the emission portion 81a of the light source unit 8 to the incident portion 12 of the laser processing head 10A, and the laser beam L2 is guided from the emission 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 partial front view of the laser processing apparatus 1 in which the laser beam L1 is guided by a mirror. In the configuration shown in FIG. 7, the mirror 3 that reflects the laser beam L1 is moved so as to face the emission part 81a of the light source unit 8 in the Y direction and the incidence part 12 of the laser processing head 10A in the Z direction. It is attached to the moving part 63 of the mechanism 6 .

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 state in which the mirror 3 faces the emitting portion 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 beam L1 emitted from the emission portion 81a of the light source unit 8 can be reliably made incident on the incidence 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 guide through the optical fiber 2 .

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

Also, 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 emission part 81a and the remaining part of the laser light from the emission part 82a.
[Regarding the operation of the laser processing device, etc.]

Next, operations 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 subsequent figures, the insides of the laser processing heads 10A and 10B are schematically shown. As shown in FIG. 8 , the supporting portion 7 supports an object 100 . Note that the symbol S in the drawing 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 an alignment camera AC and an imaging unit IR. Alignment camera AC and imaging unit IR are attached to attachment portion 65 together with laser processing head 10A. Alignment camera AC captures, for example, a device pattern using light that passes through object 100 . The image thus obtained is used for alignment of the irradiation positions of the laser beams L1 and L2 with respect to the object 100 .

The imaging unit IR images the object 100 with light that passes through the object 100 . For example, if the object 100 is a wafer containing silicon, light in the near-infrared region is used in the imaging unit IR. The imaging unit IR has a light source (not shown), an objective lens (not shown), and a photodetector (not shown). The light source outputs light that is transmissive to the object 100 . The light source is composed of, for example, a halogen lamp and a filter, and outputs light in the near-infrared region, for example. The light output from the light source is guided by an optical system such as a mirror, passes through the objective lens, and irradiates the object 100 .

The objective lens allows the light reflected by the surface of the object 100 opposite to the light incident surface to pass therethrough. That is, the objective lens allows the light propagated (transmitted) through the object 100 to pass therethrough. The numerical aperture (NA) of the objective lens is, for example, 0.45 or more. The objective lens has a correction ring. The correction ring corrects aberrations occurring in the light within the object 100, for example, by adjusting the distances between the lenses that constitute the objective lens. The photodetector detects light that has passed through the objective lens. The photodetector is composed of, for example, an InGaAs camera, and detects light in the near-infrared region. The imaging unit IR can image the modified region formed inside the object 100 and the tip of the crack extending from the modified region. That is, in the laser processing apparatus 1, the success or failure of laser processing can be confirmed non-destructively using the imaging unit IR.

A plurality of lines C extending along the X direction and arranged along the Y direction are set on the object 100 . 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 on the object 100, the illustration thereof is omitted.

The laser processing apparatus 1 carries out laser processing along each line C under the control of the controller 9 . The control unit 9 here controls the movement of the support unit 7, the mounting unit 65, and the mounting unit 66, and the irradiation of the laser beams L1 and L2 from the laser processing head 10A and the laser processing head 10B. In the laser processing apparatus 1, the controller 9 executes the first scanning process and the second scanning process. The first scanning process is a process of scanning one line C of a plurality of lines C with the laser beam L1 from the laser processing head 10A in the X direction. The second scanning process is a process of scanning another line C of the plurality of lines C with the laser beam L2 from the laser processing head 10B in the X direction.

When the controller 9 scans the laser beams L1 and L2 in the X 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 laser beams L1 and L2 are scanned. The focal points are positioned on the respective lines C and inside the object 100 . Then, in this state, by moving the supporting portion 7 in the X direction, the focal points of the laser beams L1 and L2 are moved in the X direction along the line C within the object 100 .

In particular, here, the control unit 9 executes the first scanning process and the second scanning process so as to overlap at least part of the time. That is, the control unit 9 is configured to simultaneously realize a state in which the laser light L1 is scanned along one line C and a state in which the laser light L2 is scanned along another line C. do. That is, the controller 9 simultaneously operates the laser processing head 10A and the laser processing head 10B. As a result, the throughput is clearly improved as compared with processing using one laser processing head.

When the scanning of the laser beams L1 and L2 along one line C is completed, the controller 9 independently moves the laser processing heads 10A and 10B by the distance of the line C in the Y direction (or in the Z direction if necessary). direction), and the scanning of the laser beams L1 and L2 along the next line C (that is, the first scanning process and the second scanning process) is continued. The control unit 9 forms modified regions along all the lines C by performing this operation continuously for approximately the number of lines C. FIG.

As shown in FIGS. 9 and 10, here, the control unit 9 controls the line C inside the Y direction from the line C located at one end of the object 100 in the Y direction among the plurality of lines C. , the first scan process is executed in order. Along with this, the control unit 9 sequentially executes the second scanning process from the line C located at the other end of the object 100 in the Y direction among the plurality of lines C toward the inner line in the Y direction ( This is called the main processing). The line C positioned at one end in the Y direction and the line C positioned at the other end in the Y direction have the same length in the X direction.

This point will be described in more detail. In the main processing, first, the control unit 9 moves the laser processing head 10A via the mounting unit 65 to position the focal point of the laser beam L1 at one end of the object 100 in the Y direction. It is assumed that the object 100 is positioned on the line C and inside the object 100 . At the same time, by moving the laser processing head 10B via the mounting portion 66, the controller 9 moves the focal point of the laser beam L2 to the line C located at the other end of the object 100 in the Y direction. The object 100 is positioned inside the object 100 . At this time, the position of the focal point of the laser beam L1 in the X direction and the position of the focal point of the laser beam L2 in the X direction match.

In this state, the control unit 9 moves the focal points of the laser beams L1 and L2 along the lines C in the object 100 in the X direction by moving the support unit 7 in the X direction. As a result, the first scanning process and the second scanning process for each line C are started and completed at the same time. That is, here, the first scanning process and the second scanning process overlap as a whole. Thereby, a modified region M is formed inside the object 100 along the pair of lines C. As shown in FIG.

Subsequently, the control unit 9 moves the laser processing head 10A via the mounting unit 65 to position the condensing point of the laser beam L1 inward by one from one end of the object 100 in the Y direction. It is assumed that the object 100 is positioned on the line C and inside the object 100 . At the same time, by moving the laser processing head 10B via the mounting portion 66, the control portion 9 moves the focal point of the laser beam L2 to a line located inside by one from the other end of the object 100 in the Y direction. C and inside the object 100 . At this time, the position of the focal point of the laser beam L1 in the X direction and the position of the focal point of the laser beam L2 in the X direction match.

In this state, the control unit 9 moves the support unit 7 in the X direction (in the case of reciprocating motion, the direction opposite to the X direction) to move the inside of the object 100 along each line C in the X direction (reciprocating motion). In the case of operation, the focal points of the laser beams L1 and L2 are moved in the direction opposite to the X direction. Thus, again, the first and second scanning processes for each line C are started and completed at the same time. That is, here too, the first scanning process and the second scanning process overlap as a whole. Thereby, a modified region M is formed inside the object 100 along a pair of lines C. As shown in FIG. By repeating the operation of the control unit 9, the laser processing head 10A and the laser processing head 10B can be operated simultaneously up to the inner line C of the object 100, and laser processing can be performed without waste.

In the top views of FIG. 9 and subsequent drawings, the modified region M is shown as a solid line for the sake of explanation, but it is not required that the modified region M is actually visible from the surface of the object 100. .

Here, as shown in FIG. 11, as the above operation is repeated, the positional relationship between the laser processing head 10A and the laser processing head 10B in the inner region of the object 100 is such that the distance between them in the Y direction becomes , and an unprocessed line C remains in the area of the object 100 corresponding to the distance D between the condensing parts 14. There may be In this case, it becomes difficult to simultaneously execute the first scanning process and the second scanning process as described above. Therefore, the control unit 9 executes the following processing in this case.

That is, as shown in FIG. 12, when the laser processing head 10A and the laser processing head 10B are closest to each other in the Y direction as a result of the main processing, the control unit 9 causes the laser processing head 10A to retract and move to the first position. 2 Continue the scan process. That is, henceforth, only the 2nd scanning process using the laser processing head 10B will be performed. Here, as an example, among the lines C remaining unprocessed, the second scanning process is sequentially performed outward in the Y direction (in the direction of arrow R1) from the line C closest to the laser processing head 10A in the Y direction. may be executed. While executing only the second scanning process, the control section 9 moves the imaging unit IR onto the processed line C via the mounting section 65 as shown in FIG. Imaging processing is performed for imaging the area of the object 100 including the line C by the imaging unit IR.

Then, based on the image obtained by the imaging process, the control unit 9 determines whether the modified region M and/or the crack extending from the modified region M is formed in the target object 100 in the relevant region according to regulations. judgment is made. Here, the control unit 9 may check the modified region M itself to make the determination, or may check the presence or absence or position of the tip of the crack extending from the modified region M to make the determination. As an example, as shown in FIG. 14, the control unit 9 detects that an unprocessed region RS is generated in the image along the line C where the modified region M should be formed. Then, it can be determined that the modified region M is not formed according to the regulation. In this case, the control unit 9 executes an auxiliary processing process for scanning the laser beam L1 along the line C again. Thereby, the modified region M is formed along the line C where the unprocessed region RS was generated.

In this way, when the control unit 9 determines that the modified region M and/or the crack is not formed in accordance with the regulation as a result of the determination, at least the laser beam L1 along the line C Execute auxiliary processing to scan again. Note that the control unit 9 can perform imaging processing at least at one location on the line C of the object 100 .
[Action and effect of laser processing device]

The laser processing apparatus 1 is movable along the X direction, and is arranged to face the support section 7 for supporting the target object 100 along the X direction and the Y direction and along the Y direction, Laser processing heads 10A and 10B for irradiating the object 100 supported by the support portion 7 with the laser beams L1 and L2 are provided. In addition, the laser processing apparatus 1 has a mounting portion 65 to which the laser processing head 10A is mounted and is movable along the Y direction and the Z direction, and a laser processing head 10B to which the laser processing head 10B is mounted. and a mounting portion 66 movable along each of the . The laser processing apparatus 1 is attached to the attachment portion 65 and includes an imaging unit IR that captures an image of the object 100 with light that passes through the object 100 .

In this laser processing apparatus 1, a laser processing head 10A and a laser processing head 10B are arranged on a support portion 7 that supports an object 100 so as to face each other. The laser processing head 10A and the laser processing head 10B are independently movable in two mutually intersecting directions via mounting portions 65 and 66, respectively. Therefore, it is possible to independently perform laser processing at two locations on the object 100 by scanning with the laser beams L1 and L2. Therefore, throughput can be improved.

An imaging unit IR that captures an image of the object 100 using light that passes through the object 100 is further attached to the mounting portion 65 that moves the laser processing head 10A. Therefore, for example, while laser processing is being performed by the laser processing head 10B, another part of the object 100 can be imaged by the imaging unit IR. Therefore, it is possible to check the state of laser processing in a non-destructive manner while suppressing a decrease in throughput. That is, according to the laser processing apparatus 1, it is possible to confirm the success or failure of laser processing in a non-destructive manner while improving the throughput.

In addition, the laser processing apparatus 1 moves the support portion 7, the mounting portion 65, and the mounting portion 66, irradiates the laser beams L1 and L2 from the laser processing head 10A and the laser processing head 10B, and moves the object by the imaging unit IR. A control unit 9 for controlling imaging of the object 100 is further provided. A plurality of lines C extending along the X direction and arranged along the Y direction are set on the object 100 . Then, the control unit 9 performs a first scanning process for scanning one line C of the plurality of lines C with the laser beam L1 from the laser processing head 10a in the X direction, and another line among the plurality of lines C. A second scanning process of scanning C in the X direction with the laser beam L2 from the laser processing head 10B is performed at least part of the time. Furthermore, the control unit 9 executes imaging processing for imaging the area of the target object 100 including the line C for which processing has been completed by the imaging unit IR while only the second scanning processing is being executed.

By performing the first scan process and the second scan process in duplicate in this manner, the throughput can be improved. Moreover, at the timing when only the second scanning process is being performed, the imaging process can be performed by controlling the imaging unit IR movable together with the laser processing head 10A. Therefore, it is possible to confirm the success or failure of laser processing in a non-destructive manner while improving the throughput more reliably.

Further, in the laser processing apparatus 1, the control unit 9 determines whether or not the modified region M and/or cracks are formed in the object 100 in accordance with the regulations based on the image obtained by the imaging process. If it is determined that the modified region M and / or cracks are not formed according to the regulation as a result of the determination, at least the scanning of the laser beam L1 along the line C is performed again. Execute the auxiliary machining process. Therefore, the auxiliary machining process compensates for the machining error.

In the laser processing apparatus 1, the controller 9 sequentially moves from the line C located at one end of the object 100 in the Y direction among the plurality of lines C toward the inner line C in the second direction. While performing the first scanning process, the second scanning process is sequentially performed from the line C located at the other end of the object 100 in the Y direction among the plurality of lines C toward the inner line C in the Y direction. Execute the main machining process. In this way, in the main processing, by executing the first scanning process and the second scanning process in order from the line C at the symmetrical position of the object 100 in the Y direction, the focal points of the laser beams L1 and L2 are The waste of the relative movement along the X direction with respect to the object 100 is eliminated, and the throughput is further improved.

Furthermore, in the laser processing apparatus 1, when the laser processing head 10A and the laser processing head 10B are closest to each other in the Y direction in the main processing, the control unit 9 retracts the laser processing head 10A from the area. While continuing the second scanning process, the imaging process is executed. In this case, the laser processing head 10A and the laser processing head 10B can be utilized to the maximum to improve the throughput, and the success or failure of the laser processing can be confirmed non-destructively.
[Modification]

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

15 to 18 are diagrams showing modifications of the mounting portion and the laser processing head. As shown in FIG. 15(a), the mounting portion 65 is provided on the first wall portion 21 of the housing 11 of the laser processing head 10A, and the mounting portion 66 is mounted on the first wall of the housing 11 of the laser processing head 10B. It may be provided in the portion 21 . Further, as shown in FIG. 15B, the mounting portion 65 is provided on the third wall portion 23 of the housing 11 of the laser processing head 10A, and the mounting portion 66 is mounted on the housing 11 of the laser processing head 10B. In the aspect provided on the third wall portion 23, the positions of the moving portions 63 and 64 on the mounting portions 65 and 66 may be alternated in the X direction. Further, as shown in FIG. 15(c), the mounting portion 65 is provided on the second wall portion 22 of the housing 11 of the laser processing head 10A, and the mounting portion 66 is provided on the second wall portion 22 of the housing 11 of the laser processing head 10B. It may be provided on the second wall portion 22 .

Further, as shown in FIG. 16A, the mounting portion 65 is provided on the fifth wall portion 25 of the housing 11 of the laser processing head 10A, and the mounting portion 66 is provided on the fifth wall portion 25 of the housing 11 of the laser processing head 10B. 5 may be provided on the wall portion 25 . Further, as shown in FIG. 16B, the mounting portion 65 is provided on the sixth wall portion 26 of the housing 11 of the laser processing head 10A, and the mounting portion 66 is provided on the sixth wall portion 26 of the housing 11 of the laser processing head 10B. 6 wall portion 26 may be provided. As described above, the attachment portions 65 and 66 may be attached to walls different from the fourth wall portion 24 facing each other along the Y direction. Furthermore, as shown in (c) of FIG. 16, while enlarging the distance between the first wall portion 21 and the second wall portion 22, the light condensing portion 14 is provided in the central portion of the housing 11 in the X direction. good too.

Further, as in the above example, in the laser processing apparatus 1, the laser processing head 10A and the laser processing head 10B may not be used as a pair of laser processing heads. That is, in the laser processing apparatus 1, as shown in FIG. 17(a), a pair (one type) of laser processing heads 10A are used, or as shown in FIG. A (another type of) laser processing head 10B can be used. In these cases, in a state in which the other laser processing head 10A, 10B is rotated 180° about the Z-axis direction with respect to the one laser processing head 10A, 10B, the X direction of each light condensing portion 14 is They are arranged so that their centers match. In these cases, there is no need to prepare two types of laser processing heads.

As described above, even when only the laser processing head 10A (or only the laser processing head 10B) is used, the wall portions on which the mounting portions 65 and 66 are provided can be variously changed. For example, as shown in (a) of FIG. 18, while providing the mounting portion 65 to the first wall portion 21 of the housing 11 of one laser processing head 10A, the first wall portion of the housing 11 of the one laser processing head 10A A mounting portion 66 may be provided on the two wall portions 22 . Further, as shown in FIG. 18B, while providing the mounting portion 65 on the second wall portion 22 of the housing 11 of one laser processing head 10B, the second wall portion of the housing 11 of one laser processing head 10B A mounting portion 66 may be provided on one wall portion 21 . That is, even in these cases, the mounting portions 65 and 66 may be mounted on walls different from the fourth wall portion 24 facing each other along the Y direction.

Further, in the above-described embodiment, the manner in which the imaging unit IR is attached to the attachment portion 65 to which the laser processing head 10A is attached has been described. However, the imaging unit IR may be attached to the attachment portion 66 to which the laser processing head 10B is attached, and the imaging process may be performed while only the first scanning process is being performed. In addition, the image pickup unit IR is not limited to being attached to the attachment portions 65 and 66, and is positioned so as to be movable in the Y and Z directions together with the laser processing head 10A (or the laser processing head 10B), and It can be provided at any position not interposed between the fourth wall portion 24 of the processing head 10A and the fourth wall portion 24 of the laser processing head 10B.

The control unit 9 processes the object 100 with the laser beam L1 from the laser processing head 10A and the laser beam L2 from the laser processing head 10B at mutually different wavelengths and converging positions in the Z direction. Processing (multi-wavelength processing) may be executed. Multi-wavelength processing is used, for example, when processing a wafer in which silicon (Si) and glass are bonded together (first case), or when part of the laser beams L1 and L2 incident from the back side is absorbed by the device. Therefore, it can be used in the case of processing a wafer (second case) in which the circuit may be damaged.

In the first case, both light with a wavelength for processing silicon (eg, 1064 nm) and light with a wavelength for processing glass (eg, 532 nm) need to reach the target material, so processing is performed from the glass side. The focus position of the laser beam L1 from the laser processing head 10A is aligned with the silicon through the glass, the focus position of the laser beam L2 from the laser processing head 10B is aligned with the glass, and processing is performed at the corresponding wavelength. do. In order to process a wafer on which two different types of substrates are bonded in this way by multi-wavelength processing, the wavelength for processing the description on the lower side among the wavelengths is the wavelength that transmits through the substrate on the upper side. there has to be Here, throughput is improved because multi-wavelength processing is performed using a pair of laser processing heads 10A and 10B.

On the other hand, 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 away from the device. do. The wavelength of the laser light L1 is set to a wavelength (for example, 1064 nm) that is more absorbed by the base material so that less light escapes to the device side. The wavelength (for example, 1342 nm) can be set longer than the wavelength of the laser light L1 suitable for processing the base material.

DESCRIPTION OF SYMBOLS 1... Laser processing apparatus, 7... Support part, 9... Control part, 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, IR... Imaging unit, L1, L2... Laser light.

Claims (4)

a supporter movable along a first direction for 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 to face each other along the second direction and for irradiating the object supported by the support portion with a laser beam;
a first mounting portion to which the first laser processing head is mounted and which is movable along a third direction and the second direction that intersect 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 each of the second direction and the third direction;
an imaging unit attached to the first attachment portion and configured to capture an image of the object using light that passes through the object;
Movement of the support portion, the first mounting portion, and the second mounting portion, irradiation of the laser beam from the first laser processing head and the second laser processing head, and the object by the imaging unit and a control unit that controls the imaging of
with
A plurality of lines extending along the first direction and arranged along the second direction are set on the object,
The control unit
a first scanning process of scanning the laser beam from the first laser processing head in the first direction with respect to one line of the plurality of lines; a second scanning process for scanning the laser beam from the second laser processing head in the first direction at least part of the time, and only the second scanning process is being performed; , performing an imaging process of imaging a region of the object including the processed line by the imaging unit;
Laser processing equipment. The control unit, based on the image obtained by the imaging process, determines whether or not the modified region and/or cracks are formed in the object in the region according to the regulations, and the determination As a result, if it is determined that the modified region and / or crack is not formed according to the regulation, at least the laser beam along the line is scanned again.
The laser processing apparatus according to claim 1 . The control unit sequentially performs the first scanning process from a line positioned at one end of the object in the second direction among the plurality of lines toward a line inside the second direction. main processing processing for sequentially executing the second scanning processing from a line positioned at the other end of the object in the second direction among the plurality of lines toward a line inside the second direction. run the
3. The laser processing apparatus according to claim 1 or 2 . In the main processing, when the first laser processing head and the second laser processing head are closest to each other in the second direction, the control unit retracts the first laser processing head while performing the second laser processing head. Continuing the scanning process and executing the imaging process;
The laser processing apparatus according to claim 3 .

Images