JP2013202685A - Laser processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser processing apparatus of a compact configuration, capable of efficiently removing a remnant produced during substrate division through a gap on the outside of a table without being affected by laser beam penetrated below the table.SOLUTION: A laser processing apparatus A processes a substrate by relatively moving a beam spot of a laser beam emitted from a laser radiation part 10 along a division scheduled line of a substrate M placed on a table 1. The table 1 is provided with a gap 2 which allows a remnant Ma produced at the time of substrate division to fall below the table 1. Below the table 1, there are provided a reflecting plate 13 which causes the laser beam penetrating the gap 2 to be reflected toward a sidewall 12 enclosing a lower space S of the table, and a cooling mechanism 14 for cooling the reflecting plate 13.

Description

The present invention processes a scribe line for cutting on a substrate by relatively moving a beam spot of a laser beam emitted from a laser light source along a planned cutting line of a brittle material substrate placed on a table. The present invention relates to a laser processing apparatus that divides directly. In particular, the present invention relates to a laser processing apparatus for a brittle material substrate provided with a mechanism for removing unnecessary end material (cut pieces) generated at the end of the brittle material substrate at the time of cutting.
The brittle material substrate includes glass, silicon, ceramic, semiconductor, and the like.

Conventionally, a scribe line (referred to as a kerf made of a crack that has been formed before the substrate is completely cut and does not reach the back surface) is formed on the substrate using thermal stress due to laser beam irradiation, or is scheduled to be cut There is known a method of completely dividing along a line.
For example, in Patent Document 1, a laser beam spot is relatively moved along a dividing line of a substrate placed on a table and heated locally, and following this, a coolant is discharged from a nozzle of a cooling unit. Spray. Using the compressive stress generated by heating at this time and the thermal stress distribution due to the tensile stress generated by rapid cooling, starting from the initial crack (trigger) that has been formed at the edge of the substrate in advance, the crack is directed in the direction of the line to be divided. A method for developing and forming a scribe line is disclosed. In order to completely divide the substrate on which the scribe line is formed, the substrate is completely divided through a break process.

  Further, in Patent Document 2, a scribe line that is not completely divided by the first laser irradiation is formed along a planned dividing line that divides the end material region, and a second laser whose condition is changed on the scribe line is formed. A method is shown in which, by irradiating, the crack formed in the previous scribe line is infiltrated and divided so as to reach the back surface of the substrate.

On the other hand, if the end material generated when the substrate is divided is left on the table, it causes trouble in subsequent processing. However, since the end material remaining on the table is small in width, it is difficult to remove by suction with a robot arm provided with a suction cup. In addition, when the liquid refrigerant enters between the end material and the table during laser scribing, it adheres strongly to the table surface, so it is not easy to remove even if air is blown, and it is very difficult to remove, Fine dust such as cullet generated at the time of division by air blowing rises and deteriorates the working environment.
Therefore, as shown in Patent Document 3 and the like, a method of grasping and removing an end material by a chuck has been proposed, but the mechanism of the chuck is complicated, and the entire mechanism of the chuck takes a considerable space. As a result, there is a problem that the whole cutting apparatus becomes large and expensive.

JP 2004-182530 A JP 2005-263578 A JP 2009-001484 A

Therefore, as shown in FIG. 5, a gap 17 for dropping the end material is provided outside the table 16 of the laser processing apparatus, a laser irradiation unit 18 is provided above the end material region of the substrate M to be processed in the gap 17. It is efficient to scan the laser beam from the laser irradiation unit 18 along the line to be divided and to drop the end material generated when it is divided downward from the gap 17 each time. It is.
However, if such a gap is provided outside the table 16 by the laser processing apparatus, the laser beam is transmitted through the gap below the table when the laser beam is irradiated, and reflection, scattering, and light leakage from an unexpected location occur. At the same time, the lower part of the table may be heated to adversely affect the drive part of the apparatus and the end material after dropping.

  Therefore, the present invention provides a laser having a function for removing offcuts, which can efficiently remove offcuts generated at the time of dividing the substrate from the gaps outside the table without being adversely affected by the laser beam transmitted from the gap below the table. It aims at providing a processing apparatus with a compact composition.

  In order to solve the above problems, the present invention takes the following technical means. That is, the laser processing apparatus of the present invention is a laser for processing the substrate by relatively moving the beam spot of the laser beam emitted from the laser irradiating unit along the planned dividing line of the substrate placed on the table. In the processing apparatus, a gap is provided on the outside of the table to drop the end material generated when the substrate is divided below the table, and below the table, the laser beam that has passed through the gap is placed below the table. A reflection plate that reflects toward the side wall that surrounds the space and a cooling mechanism that cools the reflection plate are provided.

  According to the laser processing apparatus of the present invention, it is possible to efficiently remove the end material from the table surface by dropping the end material generated when the substrate is divided from the gap formed outside the table to the lower side of the table. In addition, the laser beam transmitted below the table from the gap during laser processing is reflected toward the inner surface of the side wall surrounding the lower space of the table by the reflecting plate, so that the reflection direction of the laser beam is constant inside the lower space of the table. Irregular diffuse reflection can be eliminated by controlling the direction, and light leakage from an unexpected location can be prevented. In addition, since the reflecting plate that reflects the laser beam is cooled by the cooling mechanism, the temperature rise of the reflecting plate and the lower space in which the reflecting plate is stored can be suppressed, and the adverse effect on the substrate due to the temperature rise can be prevented. effective.

In the present invention, it is preferable that the reflecting plate is formed at an inclination angle at which the end material falling from the gap can be slid downward.
Thereby, the end material dropped from the gap can be received by the inclined surface of the reflecting plate and accumulated on the inclined lower portion, and can be efficiently and collectively taken out to the outside.

In the present invention, the beam spot of the laser beam is configured to be relatively movable in the XY direction along the planned dividing line, and the gap is formed around the outer periphery of the table. Good.
Thereby, the end material regions in the four-side periphery of the substrate are arranged so as to protrude into the gaps, and laser scribing in the XY directions can effectively divide the four end materials in the substrate.

1 is a schematic perspective view of a laser processing apparatus according to the present invention. Sectional drawing which shows a part of parting process by the laser processing apparatus of FIG. Sectional drawing which shows a part of other parting process by the laser processing apparatus of FIG. The top view which shows a table part. The figure explaining the subject of this invention.

The details of the present invention will be described below with reference to the drawings showing embodiments thereof.
FIG. 1 is a schematic perspective view of a laser processing apparatus A according to the present invention, FIG. 2 is a cross-sectional view showing a part of the processing state, and FIG. 3 is a cross-section showing another part of the processing state. FIG. 4 is a plan view showing a table portion.

  The laser processing apparatus A includes a horizontal table 1 on which a substrate M to be processed is placed. The table 1 includes a holding mechanism so that the substrate M placed thereon can be held at a fixed position. In the present embodiment, as the holding mechanism, the substrate is sucked and held through a large number of small air suction holes (not shown) opened in the table 1. Further, a gap 2 for dropping the end material extending in the X direction and the Y direction is provided outside the table 1. In this embodiment, the gap 2 is formed with a continuous quadrangular outline so as to go around the outer periphery of the table 1 as shown in FIG. The table 1 separated from the periphery by the gap 2 around the outer periphery is fixed to the frame 4 of the apparatus by the support material 3 on the lower surface thereof.

A bridge 7 provided with support columns 5 and 5 on both sides of the table 1 and a guide bar 6 extending horizontally in the X direction so as to connect the columns 5 and 5 extends over the table 1. Is provided.
The guide bar 6 is provided with a guide 8 extending horizontally in the X direction, and a scribe head 9 is attached to the guide 8 so as to be movable along the guide 8 in the X direction. The scribe head 9 follows a laser irradiation unit 10 in which an optical path is formed so that a laser beam from a laser light source (not shown) is emitted to the substrate M, and a heating region (laser spot) of the substrate by the laser irradiation unit 10. And the refrigerant | coolant injection part which cools immediately after a heating area | region is provided so that it may mutually rank. Note that the optical system and the refrigerant injection unit that send the laser beam from the laser light source to the laser irradiation unit 10 are omitted in order to avoid complication of the drawing.

  Further, the bridge 7 that holds the scribe head 9 is such that the lower ends of the left and right columns 5 and 5 are engaged with the rails 11 and 11, and along the rails 11 and 11 in the Y direction perpendicular to the X direction. It is formed so that it can move. Thus, the laser irradiation unit 10 can perform laser processing on the substrate M placed on the table 1 in the XY directions.

  As shown in FIG. 2, below the table 1, a reflecting plate 13 that reflects the laser beam that has passed through the gap 2 toward the side walls 12 and 12 that surround the lower space S of the table 1, and the reflecting plate 13. A cooling mechanism 14 is provided.

  The reflection plate 13 is formed in a roof shape having a ridge line along the Y direction by a metal plate material such as aluminum. The inclination angle of the reflection surface of the reflecting plate 13 reflects the laser beam that has passed through the gap 2 toward the side walls 12 and 12 that surround the lower space of the table 1 and slides the end material falling from the gap 2 downwardly. Can be formed at an angle. The angle is preferably about 30 to 60 degrees.

  The cooling mechanism 14 includes a nozzle 14 a, and the nozzle 14 a is disposed above the reflecting plate 13 and jets a coolant toward the reflecting plate 13. As the coolant, a liquid such as water or a gas such as air can be used.

2 and 3 show a step of cutting off the end material along the Y direction of the substrate M with a laser beam. As shown in FIG. 2, the substrate M is placed on the table 1 in a state where an end material equivalent portion protrudes into a gap 2 extending in the Y direction outside the table 1. In this state, the bridge 7 is moved in the Y direction along the rail 11 to scan the laser beam from the laser irradiation unit 10 to divide the end material, and to drop downward from the gap 2. As shown in FIG. 3, the dropped end material Ma slides down the inclined surface of the reflecting plate 13 and accumulates in the inclined lower portion. In this case, by arranging a tray (not shown) that can be pulled out at a portion where the end material is accumulated, the accumulated end material can be easily taken out.
Further, when cutting off the end material along the X direction of the substrate, the substrate M is placed on the table 1 with a portion corresponding to the end material protruding into a gap 2 (see FIG. 1) extending in the X direction outside the table 1. Place. Then, the scribing head 9 is moved along the guide 8 in the X direction.
In this embodiment, since the gap 2 is formed with a rectangular outline so as to go around the outer periphery of the table 1, as shown in FIG. 4, the end material in the four-side peripheral portion of the substrate M previously formed with standard dimensions. By arranging the regions so as to protrude into the rectangular gaps 2 and performing laser scribing in the XY directions, the four end materials of the substrate can be effectively divided.

  The complete cutting of the end material by the laser beam can be performed by a single laser processing by devising the laser beam irradiation optical system, increasing the output, or slowing the scanning speed. As described above, a scribe line that becomes a kerf is formed by the first laser irradiation, and the second scribe line is formed by scanning the second laser beam while changing the irradiation condition on the scribe line. The crack can be penetrated and divided until it reaches the back surface of the substrate.

At the time of scribing the laser beam, the laser beam that has passed through the gap 2 below the table is reflected by the reflector 13 toward the inner surfaces of the side walls 12, 12 surrounding the lower space of the table 1. As a result, the reflection direction of the laser beam that has passed through the gap 2 is controlled in a constant direction inside the space below the table, so that irregular irregular reflection can be eliminated and light leakage from an unexpected location can be prevented. Can do.
Further, since the reflecting plate 13 that is irradiated with the laser beam is cooled by the cooling mechanism 14, the temperature rise of the reflecting plate 13 and the lower space S that accommodates the reflecting plate 13 can be suppressed. Can be prevented.

  As mentioned above, although the typical Example of this invention was described, this invention is not necessarily specified to said embodiment, The objective is achieved and it corrects and changes suitably within the range which does not deviate from a claim. Is possible.

  INDUSTRIAL APPLICABILITY The present invention can be used for a laser processing apparatus that processes or divides a scribe line for cutting on a brittle material substrate using a laser beam.

A Laser processing apparatus M Brittle material substrate Ma End material S Lower space of table 1 Table 2 Gap 10 Laser irradiation part 12 Side wall 13 of lower space Reflecting plate 14 Cooling device

Claims (3)

A laser processing apparatus for processing a substrate by relatively moving a beam spot of a laser beam emitted from a laser irradiation unit along a planned dividing line of a substrate placed on a table,
On the outside of the table, there is provided a gap for dropping the end material generated when the substrate is divided below the table,
Below the table, a reflection plate that reflects the laser beam that has passed through the gap toward a side wall that surrounds the space below the table, and a cooling mechanism that cools the reflection plate are provided. Laser processing equipment.   The laser processing apparatus according to claim 1, wherein the reflecting plate is formed at an inclination angle at which an end material falling from the gap can be slid downward. The beam spot of the laser beam is movable relative to the X-Y direction along the line to be divided,
The laser processing apparatus according to claim 1, wherein the gap is formed around an outer periphery of the table.

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