JP2020001072A - Dividing method and dividing device for bonded substrate - Google Patents

Abstract

To facilitate operation by which a bonded substrate is divided along a scribe line.SOLUTION: A dividing method for a bonded substrate W includes: a first laser light irradiating step in which a first scribe line S1 is formed by forming first processed traces 33 positioned between an outside surface 35 of a first substrate W1 and a position away from an inside surface 36 of the substrate in a thickness direction, continuously in a plane direction, by emitting laser light from the first substrate W1 side; and a second laser light irradiating step in which a second scribe line S2 is formed by forming second processed traces 35 positioned between an inside surface 38 of a second substrate W1 and a position P2 away from an outside surface 37 of the substrate in a thickness direction, continuously in the plane direction along the first processed traces 33, by emitting laser light with a laser intensity distribution different from that in the first laser light irradiating step from the second substrate side.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method and an apparatus for cutting a bonded substrate, and more particularly to a method for forming a scribe line by intermittently performing internal processing of a bonded substrate by a pulse using a laser device in a planar direction.

As a method for scribing a glass substrate, laser processing is known. In laser processing, for example, an infrared picosecond laser is used. In this case, there is known a method of forming a scribe line by forming a plurality of laser filaments by intermittently performing internal processing by a laser in a planar direction (for example, see Patent Document 1).
In the technique disclosed in US Pat. No. 6,037,097, a focused laser beam is composed of pulses having an energy and a pulse duration selected to create a filament in a substrate. A scribe line is formed by forming a plurality of filaments side by side in the plane direction.

JP-T-2013-536081

Generally, when scribe line processing is performed by forming a filament by laser processing, a large force is required to separate the glass substrate along the scribe line. Therefore, at the time of separation along the scribe line, chipping, chipping, cracking, and the like are likely to occur, and the yield is reduced.
In particular, when the target is a bonded substrate, it is desired to cut the scribe lines of the two substrates at the same time. The bonded substrate is, for example, a mother substrate in which a substrate on which a thin film transistor (TFT) is formed and a substrate on which a color filter (CF) is formed are bonded via a sealant. By dividing the mother substrate, individual liquid crystal panels are obtained.
However, depending on the position of the processing mark in the thickness direction of the scribe line, it may not be easy to simultaneously cut the bonded substrate.

  An object of the present invention is to facilitate an operation of cutting a bonded substrate along a scribe line.

  Hereinafter, a plurality of modes will be described as means for solving the problems. These embodiments can be arbitrarily combined as needed.

According to one aspect of the present invention, a method for cutting a bonded substrate having a first substrate and a second substrate includes the following steps.
◎ By irradiating the laser beam from the first substrate side, the first processing mark located between the outer surface of the first substrate and the position away from the inner surface in the thickness direction is continuously formed in the plane direction. A first laser beam irradiating step of forming a first scribe line by applying a laser beam having a laser intensity distribution different from that of the first laser beam irradiating step from the side of the second substrate; A second laser beam irradiation for forming a second scribe line by continuously forming a second processing mark located between the inner side surface and a position distant from the outer side surface in a planar direction along the first processing mark. Step ◎ A dividing step of dividing the first substrate and the second substrate along the first scribe line and the second scribe line by applying a force to the first substrate and the second substrate. Thickness direction "Is located between the outer surface of the first substrate and a position distant from the inner surface." Means that the first processing trace extends from the outer surface of the first substrate toward the inner surface. It means that it ends at a remote position.
Further, “the second processing mark is located between the inner surface of the second substrate and the position away from the outer surface in the thickness direction” means that the second processing mark is from the inner surface of the second substrate to the outer surface. Extending towards, but terminating away from the outer surface.

According to this method, it is easy to simultaneously break two bonded substrates. This is because the first processing mark on the first substrate and the second processing mark on the second substrate extend in the thickness direction from the same surface in the thickness direction (the outer surface of the first substrate and the inner surface of the second substrate). This is because the first scribe line and the second scribe line are opened from the same side. Accordingly, when a force is applied to the bonded substrate so that the outer surface of the first substrate is opened along the first scribe line, the first substrate and the second substrate are easily formed along the first scribe line and the second scribe line. Divided into
In addition, since the first processing trace is formed only up to a position distant from the inner surface of the first substrate, the thermal influence on the sealing material between the first substrate and the second substrate is suppressed.

  The first laser light irradiation step and the second laser light irradiation step may be performed by spatial light phase modulation.

An apparatus for cutting a bonded substrate having a first substrate and a second substrate according to another aspect of the present invention includes a laser device and a substrate cutting apparatus.
By irradiating a laser beam from the first substrate side, the laser device continuously connects a first processing mark located between an outer surface of the first substrate and a position away from the inner surface in the thickness direction in a plane direction. A first laser beam irradiation step of forming a first scribe line by forming the first scribe line;
By irradiating a laser beam having a laser intensity distribution different from that of the first laser beam irradiating step from the second substrate side, the second laser beam located between the inner surface and the position remote from the outer surface of the second substrate in the thickness direction A second laser beam irradiation step of forming a second scribe line by forming two processing marks continuously in a planar direction along the first processing mark.
The substrate cutting device executes a cutting step of cutting the first substrate and the second substrate along the first scribe line and the second scribe line by applying a force to the first substrate and the second substrate.
With this apparatus, it is easy to simultaneously break two bonded substrates. This is because the first processing mark on the first substrate and the second processing mark on the second substrate extend in the thickness direction from the same surface in the thickness direction (the outer surface of the first substrate and the inner surface of the second substrate). This is because the first scribe line and the second scribe line are opened from the same side. Accordingly, when a force is applied to the bonded substrate so that the outer surface of the first substrate is opened along the first scribe line, the first substrate and the second substrate are easily formed along the first scribe line and the second scribe line. Divided into
In addition, since the first processing trace is formed only up to a position distant from the inner surface of the first substrate, the thermal influence on the sealing material between the first substrate and the second substrate is suppressed.

  In the method and the apparatus for cutting a bonded substrate according to the present invention, an operation of cutting the bonded substrate along a scribe line is facilitated.

FIG. 1 is a schematic diagram of a laser processing apparatus according to a first embodiment of the present invention. FIG. 4 is a schematic operation explanatory diagram of the spatial light phase modulator. 5 is a schematic cross section of a substrate in a scribe line forming step. FIG. 3 is a schematic diagram illustrating the configuration and operation of a substrate cutting device. FIG. 3 is a schematic diagram illustrating the configuration and operation of a substrate cutting device. FIG. 9 is a schematic diagram illustrating the configuration and operation of a substrate cutting device according to a second embodiment. FIG. 9 is a schematic diagram illustrating the configuration and operation of a substrate cutting device according to a second embodiment.

1. First Embodiment (1) Overall Configuration The overall configuration of a laser processing apparatus 1 will be described with reference to FIGS. FIG. 1 is a schematic diagram of a laser processing apparatus according to a first embodiment of the present invention. FIG. 2 is a schematic diagram illustrating the operation of the spatial light phase modulator.

The laser processing apparatus 1 is an apparatus that forms a scribe line on a bonded substrate W (hereinafter, “substrate W”). The substrate W has a first substrate W1 and a second substrate W2. The substrate W is, for example, a liquid crystal glass substrate.
As shown in FIG. 2, the first substrate W1 and the second substrate W2 are bonded together by a sealant 40. The first substrate W1 has an outer side surface 35 and an inner side surface 36. The second substrate W2 has an outer surface 37 and an inner surface 38. A seal member 40 is disposed between the inner side surface 36 and the inner side surface 38.

  The laser processing device 1 has a first laser device 3A. The first laser device 3A is a device that forms a first scribe line S1 on a first substrate W1.

The first laser device 3A has a first laser oscillator 15A and a first laser control unit 17A. The first laser oscillator 15A is, for example, a picosecond laser having a wavelength of 340 to 1100 nm. The first laser control unit 17A can control the drive and laser power of the first laser oscillator 15A.
The laser processing device 1 has a first transmission optical system 5A. The first transmission optical system 5A has a first spatial light phase modulator 21A that modulates the laser light emitted from the first laser device 3A. The first spatial light phase modulator 21A is, for example, a transmission type, and may be a transmission type spatial light transport modulator (SLM: Spatial Light Modulator). A first spatial light phase modulator may use a reflective spatial light transport modulator such as a reflective liquid crystal on silicon (LCOS) spatial light phase modulator instead of the transmission spatial light transport modulator. The modulator 21A modulates the laser beam and emits the first laser beam L1 by irradiating the laser beam downward. The first transmission optical system 5A has a first condenser lens 23A below the first spatial light phase modulator 21A.

The laser processing device 1 includes a second laser device 3B. The second laser device 3B is a device that forms a second scribe line S2 on the second substrate W2.
The second laser device 3B has a second laser oscillator 15B and a second laser control unit 17B. The second laser oscillator 15B is, for example, a picosecond laser having a wavelength of 340 to 1100 nm. The second laser control unit 17B can control the driving of the second laser oscillator 15B and the laser power.
The laser processing device 1 has a second transmission optical system 5B. The second transmission optical system 5B has a second spatial light phase modulator 21B that modulates the laser light emitted from the second laser device 3B. The second spatial light phase modulator 21B may be an SLM like the first spatial light phase modulator 21A. The second spatial light phase modulator 21B modulates the laser light and irradiates the second laser light L2 upward. The second transmission optical system 5B has a second condenser lens 23B above the second spatial light phase modulator 21B.

The laser processing device 1 has a drive unit 25. The driving unit 25 applies a predetermined voltage to each pixel electrode in the first spatial light phase modulator 21A and the second spatial light phase modulator 21B to display a predetermined modulation pattern on the liquid crystal layer. Modulation is performed as desired by the first spatial light phase modulator 21A and the second spatial light phase modulator 21B. Here, the modulation pattern displayed on the liquid crystal layer includes, for example, a position where a processing mark is to be formed, a wavelength of a laser beam to be irradiated, a material of an object to be processed, and a first transmission optical system 5A and a second transmission optical system. It is derived in advance based on 5B, the refractive index of the object to be processed, and the like, and is stored in the control unit 9.
As a result, as shown in FIG. 2, the first spatial light phase modulator 21A and the second spatial light phase modulator 21B can form an arbitrary number of beams, and can perform simultaneous processing with the number of beams. Become.

  The laser processing device 1 has a driving device 7 that holds and drives the substrate W. The driving device 7 is moved by the driving device operation unit 13. The drive device operation unit 13 moves the drive device 7 in the horizontal direction.

The laser processing device 1 includes a control unit 9. The control unit 9 has a processor (for example, CPU), a storage device (for example, ROM, RAM, HDD, SSD, etc.), and various interfaces (for example, A / D converter, D / A converter, communication interface, etc.). It is a computer system. The control unit 9 performs various control operations by executing a program stored in the storage unit (corresponding to part or all of the storage area of the storage device).
The control unit 9 may be configured by a single processor, or may be configured by a plurality of independent processors for each control.

The control unit 9 can control the first laser control unit 17A and the second laser control unit 17B. The control unit 9 can control the driving unit 25. The control unit 9 can control the drive device operation unit 13.
Although not shown, a sensor for detecting the size, shape and position of the substrate W, sensors and switches for detecting the state of each device, and an information input device are connected to the control unit 9.

(2) Scribing Method A scribing method using the laser processing apparatus 1 will be described with reference to FIG. FIG. 3 is a schematic cross section of the substrate in a scribe line forming step.

(2-1) First Laser Light Irradiation Step The first scribe line S1 is formed by irradiating the first laser light L1 from the first substrate W1 side. Specifically, a plurality of first processing traces 31 formed along the optical axis inside the first substrate W1 are continuously formed in a plane direction (in a direction orthogonal to the paper surface). The position where the first processing mark 31 is formed in the thickness direction is a region between the outer surface 35 of the first substrate W1 and a position P1 apart from the inner surface 36. That is, the first processing mark 31 is not formed near the inner side surface 36 of the first substrate W1.
In this embodiment, a plurality of first processing traces 31 are simultaneously formed in the thickness direction at one location of the first scribe line S1 in plan view.

(2-2) Second Laser Light Irradiation Step The second scribe line S2 is formed by irradiating the second laser light L2 from the second substrate W2 side. Specifically, a plurality of second processing marks 33 formed along the optical axis inside the second substrate W2 are formed continuously in a planar direction (in a direction orthogonal to the paper surface) along the first processing marks 31. You.
The laser intensity distribution at this time is different from the laser intensity distribution in the first laser light irradiation step. The formation position of the second processing mark 33 in the thickness direction is a region between the inner surface 38 of the second substrate W2 and a position P2 apart from the outer surface 37. That is, the second processing mark 33 is not formed near the outer surface 37 of the second substrate W2.
In this embodiment, at one location of the second scribe line S2 in plan view, the plurality of second processing marks 33 are formed simultaneously in the thickness direction.

(3) Board Cutting Apparatus The board cutting apparatus 101 will be described with reference to FIGS. 4 and 5 are schematic diagrams illustrating the configuration and operation of the substrate cutting device. Note that the substrate cutting device 101 may be controlled by the control unit 9 of the laser processing device 1 or may be controlled by another control unit.
The substrate cutting device 101 is a device that cuts out a product by dividing and removing offcuts from a substrate on which scribe lines are formed.
The substrate cutting apparatus 101 includes a first transport unit 103, a break unit 105, and a second transport unit 107 in order from the upstream.
The substrate W is transported with the first substrate W1 arranged on the upper side and the second substrate W2 arranged on the lower side. A first scribe line S1 is formed on the first substrate W1, and a second scribe line S2 is formed on the second substrate W2. The extending direction of the first scribe line S1 and the second scribe line S2 is a direction orthogonal to the substrate transport direction.
In this embodiment, the first scribe line S1 and the second scribe line S2 divide the product body and the scrap W3.

The first transport unit 103 is a device for transporting the substrate W toward the downstream side in the substrate transport direction, and is configured by, for example, a belt conveyor. Specifically, the first transport unit 103 has a pair of rollers 111 and a belt 113 wound around them. A belt 113 transports the substrate W downstream in the substrate transport direction by a drive motor (not shown) rotating each roller 111 clockwise.
The break unit 105 is installed downstream of the first transport unit 103 in the substrate transport direction. The break unit 105 has a first division unit 117 and a second division unit 119. The first division unit 117 and the second division unit 119 are arranged at positions facing each other in the vertical direction. More specifically, the first division unit 117 and the second division unit 119 are arranged at positions facing each other via the conveyance path of the substrate W, and the first division unit 117 is arranged above the conveyance path, The second division unit 119 is disposed below the transport path.

The first division unit 117 has a pair of break bars 127. The break bars 127 are arranged on the first substrate W1 side, and are arranged so as to be located on both sides of the first scribe line S1 in the substrate transport direction at the time of division. The break bar 127 extends in a direction parallel to the transfer surface 121 of the first transfer unit 103 and orthogonal to the substrate transfer direction. The lower portion of the break bar 127 is formed in a triangular prism shape extending in a direction parallel to the transfer surface 121 and orthogonal to the substrate transfer direction.
The break bar 127 is installed so as to be able to move up and down between an operation position and a non-operation position.

The second divided unit 119 has a backup bar 129. The backup bar 129 is arranged on the second substrate W2 side, and is arranged so as to coincide with the second scribe line S2 at the time of division. The backup bar 129 extends in a direction parallel to the transfer surface 121 of the first transfer unit 103 and orthogonal to the substrate transfer direction. The upper portion of the backup bar 129 is formed in a triangular prism shape extending in a direction parallel to the transfer surface 121 and orthogonal to the substrate transfer direction.
The backup bar 129 is installed so as to be able to move up and down between an operation position and a non-operation position.

  The second transport unit 107 transports the divided substrate W placed on the transport surface downstream. The second transport unit 107 has a pair of rollers 135, a belt 137 wound around them, and a second drive motor (not shown). The second transport unit 107 has a configuration similar to that of the first transport unit 103 described above, and a description thereof will be omitted.

(4) Break Operation First, the substrate W, on which the first and second scribe lines S1 and S2 are formed on both surfaces by the laser processing apparatus 1, is placed on the transport surface of the first transport unit 103. Next, the first transport unit 103 transports the substrate W to the downstream side in the substrate transport direction. As a result, the first scribe line S1 and the second scribe line S2 of the substrate W are arranged at the break positions of the break unit 105.
At this time, both the first divided unit 117 and the second divided unit 119 are vertically separated from the substrate W.

Next, as shown in FIG. 4, in the second divided unit 119, the backup bar 129 is moved to a position where the substrate W comes into contact with the second substrate W2. Thereby, the tip of the backup bar 129 contacts the position corresponding to the second scribe line S2.
Subsequently, as shown in FIG. 5, in the first division unit 117, the pair of break bars 127 are moved to a contact position where the break bar 127 contacts the substrate W. Specifically, the distal ends of the pair of break bars 127 abut on a position separated from the first scribe line S1 on both sides in the substrate transport direction. Thereby, the scrap W3 is broken from the product portion of the substrate W along the first scribe line S1 and the second scribe line S2.

In the above dividing operation, it is easy to simultaneously break two substrates W. This is because the first processing trace 31 of the first substrate W1 and the second processing trace 33 of the second substrate W2 are separated from the same surface in the thickness direction (the outer surface 35 of the first substrate and the inner surface 38 of the second substrate). It is because it extends in the direction. Thus, when a force is applied to the substrate W so that the outer surface 35 of the first substrate W1 opens along the first scribe line S1, the first scribe line S1 and the second scribe line S2 are easily separated.
Further, since the first processing mark 31 is formed only up to a position distant from the inner side surface 36 of the first substrate W1, the thermal influence on the sealing material 40 is suppressed.

2. Second Embodiment Another embodiment of the substrate cutting device will be described with reference to FIGS. 6 and 7 are schematic diagrams illustrating the configuration and operation of the substrate cutting device according to the second embodiment.
The substrate cutting device 201 is a device that cuts out a product by dividing and removing offcuts from a substrate on which scribe lines are formed.

The substrate cutting device 201 has a holding table 203. The holding table 203 has a horizontal suction surface 203a, on which a substrate W to be processed is placed. The suction surface 203a of the holding table 203 is provided with a number of air suction holes (not shown) for stably holding the substrate W.
The holding table 203 is an adsorption table for adsorbing and fixing the product portion of the substrate W, in particular. The substrate W is placed on the holding table 203 such that the second scribe line S2 coincides with the edge of the holding table 203.

The substrate cutting device 201 has a chuck mechanism 211. The chuck mechanism 211 is a device that grips the end material W3 that is one end of the substrate W protruding from the suction surface 203a of the holding table 203 so as to grip it.
The chuck mechanism 211 has a chuck member 213. The chuck member 213 is configured to be freely opened and closed.
The chuck mechanism 211 has a gripping operation mechanism (not shown) for driving the chuck member 213.
The substrate cutting device 201 further includes a pressing mechanism 215 for pressing and fixing the product portion of the substrate W (the portion on the opposite side to the scrap W3 across the first and second scribe lines S1 and S2) from above. ing.

The substrate cutting device 201 has a rotating mechanism (not shown). The rotation mechanism holds the chuck member 213 so that the chuck member 213 can rotate by a predetermined angle around a shaft extending in a direction orthogonal to the paper surface. The rotation mechanism has, for example, a rotation motor.
The substrate cutting device 201 has a lifting mechanism (not shown). The elevating mechanism is an apparatus for elevating the chuck member 213 and a rotating mechanism (not shown). The elevating mechanism has, for example, a pressure cylinder.

As shown in FIG. 6, the substrate cutting device 201 grips the scrap W3 with the chuck member 213.
Next, the substrate cutting device 201 separates the scrap W3 from the product by lifting and lowering the chuck member 213 as shown in FIG. At this time, the pressing mechanism 215 holds the product portion of the substrate W between the holding table 203 and the product portion so as not to float from the holding table 203.
As a result, the cutting is performed along the first scribe line S1 of the first substrate W1 and the second scribe line S2 of the second substrate W2.
In this embodiment, the same effects as in the first embodiment can be obtained.

3. Other Embodiments A plurality of embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the invention. In particular, a plurality of embodiments and modifications described in this specification can be arbitrarily combined as needed.
The substrate is not particularly limited as long as it is a substrate made of a brittle material such as glass, a semiconductor wafer, and ceramics.
In the above-described embodiment, the substrate cutting device is a device for removing offcuts of the substrate, but may be another substrate cutting device.

  INDUSTRIAL APPLICATION This invention can be widely applied to the method and apparatus which form a scribe line by performing internal processing of a board | substrate by the pulse using a laser apparatus intermittently in a plane direction.

1: laser processing device 3A: first laser device 3B: second laser device 5A: first transmission optical system 5B: second transmission optical system 7: drive device 9: control unit 13: drive device operation unit 15A: first laser Oscillator 15B: second laser oscillator 17A: first laser controller 17B: second laser controller 21A: first spatial light phase modulator 21B: second spatial light phase modulator 23: drive unit 31: first processing mark 33 : Second processing mark 35: outer surface 36: inner surface 37: outer surface 38: inner surface 40: sealing material 101: substrate cutting device 201: substrate cutting device S1: first scribe line S2: second scribe line W1: first 1 substrate W2: 2nd substrate

Claims (3)

A method for cutting a bonded substrate having a first substrate and a second substrate,
By irradiating a laser beam from the first substrate side, a first processing mark located between an outer surface and a position away from an inner surface of the first substrate in a thickness direction is continuously formed in a plane direction. Performing a first laser beam irradiation step of forming a first scribe line,
By irradiating a laser beam having a laser intensity distribution different from the first laser beam irradiating step from the second substrate side, between the inner surface and the position apart from the outer surface of the second substrate in the thickness direction. A second laser beam irradiation step of forming a second scribe line by forming a second processing mark located continuously in a planar direction along the first processing mark;
A dividing step of dividing the first substrate and the second substrate along the first scribe line and the second scribe line by applying a force to the first substrate and the second substrate,
A method for cutting a bonded substrate comprising:   2. The method according to claim 1, wherein the first laser light irradiation step and the second laser light irradiation step are performed by spatial light phase modulation. 3. An apparatus for cutting a bonded substrate having a first substrate and a second substrate,
By irradiating a laser beam from the first substrate side, a first processing mark located between an outer surface and a position away from an inner surface of the first substrate in a thickness direction is continuously formed in a plane direction. A first laser light irradiating step of forming a first scribe line, and irradiating a laser light having a laser intensity distribution different from the first laser light irradiating step from the second substrate side in the thickness direction. A second scribe line is formed by continuously forming a second processing mark located between an inner surface of the second substrate and a position distant from the outer surface in a planar direction along the first processing mark. A laser device that executes a second laser light irradiation step of
By applying a force to the first substrate and the second substrate, a substrate dividing step for performing a dividing step of dividing the first substrate and the second substrate along the first scribe line and the second scribe line, respectively. Equipment and
For cutting a bonded substrate.

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