TWI658016B - Processing method of brittle material substrate - Google Patents

Abstract

The method for processing a brittle material substrate according to the present invention can suppress chipping of the substrate when cutting the brittle material substrate.

The invention provides a substrate processing method including the following steps: laser processing is performed on the surface of the brittle material substrate to a certain depth along a guide line provided at a certain distance from the processing line of the brittle material substrate; and, along the brittle material substrate The processing line performs laser processing on the brittle material substrate from the back surface to the surface of the substrate; it has the ability to suppress the occurrence of chipping of the brittle material substrate when cutting the brittle material substrate, reduce the defect rate, and produce. The effect of increased efficiency.

Description

Processing method of brittle material substrate

The present invention relates to a method for processing a brittle material substrate, and more specifically, it relates to a method for processing a brittle material substrate capable of suppressing chipping of the substrate when cutting the brittle material substrate.

Generally, when cutting a fragile material substrate such as a glass substrate or a semiconductor wafer, there is a problem that an irregular shape generally called a chip is generated along the edge of the cutting line.

On the other hand, a processing method that uses a laser beam in a non-contact processing method when cutting a brittle material substrate has been used recently.

In a substrate processing method using a laser beam, a substrate is processed by irradiating a substrate with a laser beam oscillated from a laser oscillation device through a laser optical system. The processing method of a brittle material substrate using a laser beam, because a beam spot is formed at a portion where the substrate is to be processed, and thermal energy is applied to process the substrate, so that precise processing can be performed and the processing step time can be reduced.

However, even in the processing method of a brittle material substrate using such a laser beam, when cutting the brittle material substrate, there are cases where chipping occurs at the edge of the substrate and at the place where the cutting process is completed. Crumbs.

The present invention is to solve the above-mentioned problems, and an object thereof is to provide a processing method of a brittle material substrate capable of suppressing chipping of the substrate when cutting the brittle material substrate.

The method for processing a brittle material substrate of the present invention to achieve the above-mentioned object includes the following steps: along a guide line that is arranged at a certain interval from the processing line of the brittle material substrate, and mine the surface of the brittle material substrate at a certain depth Laser processing; and, along the processing line of the brittle material substrate, laser processing is performed on the brittle material substrate from the back surface to the surface direction of the brittle material substrate.

The method for processing a brittle material substrate may further include the following steps: after the step of laser processing the surface of the brittle material substrate at a certain depth along the guide line, the laser beam spot is directed toward the brittleness The back of the material substrate moves.

In the step of performing the laser processing, the brittle material substrate may be processed by moving the beam spot of the laser by a laser optical system in a state where the brittle material substrate is fixed.

The laser used in this laser processing can be a nanosecond pulsed laser.

The guide line can be set according to the size of the beam spot of the laser and separated from the processing line at a distance of 40-100 μm.

The processing depth of the guide wire can be set to 40 ~ 60μm.

A pair of the guide lines can be provided on both sides of the processing line with a certain interval.

According to the method for processing a brittle material substrate of the present invention, it is possible to suppress the occurrence of chipping of the substrate when cutting the brittle material substrate.

This has the effect of reducing the defective rate and improving the production efficiency during the cutting process of the brittle material substrate.

10‧‧‧ substrate

11‧‧‧Processing Line

12‧‧‧ Guide

FIG. 1 is a view showing a surface of a substrate processed by a method for processing a brittle material substrate according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG. 1.

FIG. 3 is a diagram for explaining the effect of preventing crack diffusion in the substrate of FIG. 1.

FIG. 4 is a flowchart of a method for processing a brittle material substrate according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, when reference numerals are given to constituent elements of each drawing, the same constituent elements are set to have the same symbol as much as possible even if they are shown on different drawings. In addition, although a preferred embodiment of the present invention is described below, the technical idea of the present invention is not limited or limited thereto, and it is of course possible to be modified and variously implemented by a general skilled person.

FIG. 1 is a view showing a surface of a substrate processed by a method for processing a brittle material substrate according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along a line II-II in FIG. 1.

1 to 2 in this way are for conceptually and clearly understanding the present invention, and only the main features are conceptually shown.

4 is a flowchart of a method for processing a brittle material substrate according to an embodiment of the present invention. Referring to FIG. 4, a method for processing a brittle material substrate according to an embodiment of the present invention includes: guiding lines arranged at a certain interval from the processing line of the brittle material substrate, and Step (S100) for laser processing at a certain depth; Step (S200) for moving the laser beam spot toward the back of the substrate; along the processing line of the substrate, laser processing of the substrate from the back of the substrate to the surface Step (S300).

In the step (S100) of performing laser processing on the surface of the substrate at a certain depth along the guide line, a groove with a certain depth is formed on the surface of the substrate along the guide line by a laser processing device.

Referring to FIG. 1 and FIG. 2, the guide line is provided at a certain interval from the processing line. The processing line is a line for actually processing the substrate, and the guide line is a line for forming a groove at a certain depth at a certain distance from the processing line.

The processing line shown in FIG. 1 is a line formed by performing a hole processing on a part of the substrate.

A laser processing apparatus (not shown) used in this embodiment processes a substrate by passing a laser beam oscillated from a laser oscillation section onto a substrate through a laser optical system. The control unit of the laser processing device controls the laser optical system so that the laser beam spot is formed on a portion of the substrate to be processed to process the substrate.

In other words, the laser processing device processes the substrate by controlling the laser optical system and moving the beam spot along the guide line while the brittle material substrate to be processed is fixed at a predetermined position.

In the laser processing apparatus, the beam spot can also be moved in the X-, Y-, and Z-axis directions (the thickness direction of the substrate) shown in FIGS. 1 and 2 by the laser optical system. Therefore, the laser processing device moves the beam spot in the X and Y axis directions along the guide line to process the substrate, and also moves in the Z axis direction to process the surface of the substrate with a certain depth.

In the step (S200) of moving the laser beam spot toward the back surface of the substrate, after the groove processing is performed on the surface of the substrate along the guide line, the laser processing device is controlled in a state where the laser output is turned off The laser optical system moves the position where the beam spot is formed toward the processing line on the back surface of the substrate. Also at this time, since the substrate is moved only by the position of the beam spot by the laser optical system in a fixed state, precise processing can be performed without causing errors due to substrate movement.

In the step (S300) of performing laser processing on the substrate from the back surface of the substrate to the surface along the processing line of the substrate, cutting processing is performed from the back surface of the substrate to the surface by the laser processing device along the processing line.

Also in this step (S300), the substrate is maintained in a fixed state, and the substrate is processed while the beam spot is moved along the processing line on the rear surface of the substrate by the laser optical system of the laser processing device. While moving the beam spot along the processing line, the substrate is cut along the processing line because it moves from the back surface of the substrate toward the surface at a certain speed and moves in the Z-axis direction.

Next, the effect of a method for processing a brittle material substrate having such a structure will be described.

A groove of a certain depth formed along the guide line on the surface of the substrate is used to prevent the part along the cutting line from finishing along the cutting line when the substrate is cut along the processing line when the substrate is cut The resulting debris or cracks spread.

FIG. 3 is a diagram illustrating the effect of preventing crack diffusion in the substrate of FIG. 1. FIG.

Referring to FIG. 3, a guide wire formed by processing a surface of a substrate in advance is used to prevent cracks generated along the edge of the processing portion of the surface of the substrate from cutting off the substrate from spreading to the outside of the guide wire.

This has the effect of minimizing debris and reducing the rate of defective products.

Debris generated at the edge of the cutting line when the substrate is cut by laser is mainly generated at the place where the cutting process is completed due to heat conduction energy and the like. Therefore, the guide wire that has been processed in advance is formed with a groove in advance on the surface portion of the substrate cutting process, which can prevent the chip from spreading when such a chip is generated and reduce the product defect rate.

The guide line is set at a certain distance from the processing line in consideration of the size of the laser beam spot. In the case where the guide line is too close to the processing line, there may be a case where a groove portion formed in advance along the guide line is processed by laser in the step of processing along the processing line. In addition, when the guide line is too far away from the processing line, there is a case where the effect of preventing the debris generated at the edge of the processing line from spreading is not provided. Therefore, in consideration of such conditions, the guide line is preferably spaced from the processing line by 40 to 100 μm.

The processing depth of the guide line is determined by considering the area where the debris is mainly generated. In addition, when the substrate has a reinforcing layer, since debris is likely to be generated in the reinforcing layer, it is processed at a depth capable of penetrating the reinforcing layer. Generally speaking, considering the processing efficiency, it is preferred that the guide wire be processed at a depth of 40 to 60 μm.

The method for processing a brittle material substrate according to the present invention has the following effects.

First, as described above, during cutting of a brittle material substrate, it is possible to prevent the spread of chips or cracks generated along the edge of the cutting line, reduce the defective rate of the product, and improve productivity.

Second, since the laser optical system is controlled in a state where the substrate is fixed, and only the laser beam spot is moved for processing, the processing accuracy is high.

Third, in laser processing of brittle material substrates, nanosecond pulse lasers can be used to save production costs. In order to reduce thermal damage to the substrate and reduce chipping and cracks during laser processing of a brittle material substrate, a picosecond pulsed laser can be used. However, the processing equipment using the picosecond pulse laser is extremely expensive compared to the processing equipment using the nanosecond pulse laser, and there is a problem that the manufacturing unit price becomes higher. However, in the case of using the processing method of the present invention, the defect rate can also be reduced in a processing device using a nanosecond pulse laser, which has the effect of saving production costs.

On the other hand, although in the above-mentioned embodiment, the present invention has been described with reference to a processing line for performing a hole-cutting process on a certain region of a brittle material substrate, the present invention can be variously modified.

For example, in the case where a hole is not processed in a certain region of the substrate, but the substrate is simply cut and processed, the processing method of the present invention can also be used. In this case, guide wires may be provided at a certain interval on both sides of the processing line of the substrate. That is, in the hole-cutting process, although the hole-opening portion is discarded, it is not necessary to form a guide line in the hole-opening portion. However, if the processing line is used as a reference and both sides are used portions, then Guide lines are formed on both sides of the processing line for processing.

The above description is merely illustrative of the technical idea of the present invention. If it is a person with ordinary knowledge in the technical field to which the present invention pertains, various modifications, Changes and replacements. Therefore, the embodiments and drawings disclosed in the present invention are not intended to limit the technical idea of the present invention, but are used as examples for illustration, and are not intended to limit the present invention by such embodiments and drawings. The scope of rights. The scope of the right of the present invention should be interpreted in terms of the scope of patent application, and should be within the scope equivalent to that of the present invention. Technical ideas should be construed as being included in the scope of rights of the present invention.

Claims (7)

A method for processing a brittle material substrate is characterized in that it comprises the steps of: following a guide line arranged at a certain distance from a processing line of a brittle material substrate having a front surface and a back surface; 1 laser processing; and along the processing line of the brittle material substrate, a second laser processing is performed on the brittle material substrate from the back surface of the brittle material substrate to the surface direction; the second laser processing is a cutting process; When the cutting process is performed along the processing line, the process reaches the substrate surface. For example, the method for processing a brittle material substrate according to item 1 of the patent application scope further includes the following steps: after the step of laser processing the surface of the brittle material substrate at a certain depth along the guide line, the laser is made The beam spot moves toward the back of the brittle material substrate. For example, the method for processing a brittle material substrate according to item 1 or 2 of the patent application scope, wherein in the step of performing the first laser processing and the second laser processing, in a state where the brittle material substrate is fixed, borrow The laser beam system moves the laser beam spot to process the brittle material substrate. For example, the method for processing a brittle material substrate according to item 1 or 2 of the patent application scope, wherein the laser used in the first laser processing and the second laser processing is a nanosecond pulse laser. For example, the processing method of a brittle material substrate according to item 1 or 2 of the patent application scope, wherein the guide wire can be separated from the processing line into a space of 40 to 100 μm according to the size of the laser beam spot. Way setting. For example, the processing method of a brittle material substrate according to item 1 or 2 of the patent application scope, wherein the processing depth of the guide wire is 40 to 60 μm. For example, a method for processing a brittle material substrate according to item 1 or 2 of the patent application scope, wherein a pair of guide wires are provided on both sides of the processing line with a certain interval.