JP2006248075A - Method and apparatus for working substrate using laser beam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for working a substrate which can demonstrate stable substrate-parting performance by using laser beams without leaving micro cracks, cutting powder, etc. , in a parting place. <P>SOLUTION: A laser beam generating means 11 generating laser beams and an optical means 15 forming a focus S by converging the laser beams 12 from the means 11 are provided. The focus position of the laser beams is reciprocated in the thickness direction (Z-Z' direction) of the substrate 17 and simultaneously moved along a parting schedule line (X direction) of the substrate. A channel (scribe line) 17a is formed along the parting schedule line by the heat energy of the laser beams. By the reciprocation in the Z-Z' direction of the focus S, the channel 17a can be formed to a deeper position from the surface of the substrate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  According to the present invention, for example, a substrate to be processed is formed by irradiating a substrate to be processed such as a glass substrate with a laser beam along a surface of a line to be cut, thereby dividing the substrate or forming a cutting groove in the substrate. The present invention relates to a processing method and a processing apparatus.

  For example, in liquid crystal display devices and organic EL (electroluminescence) display panels, semiconductor elements such as wiring and TFTs made of ITO corresponding to a plurality of panels on a large glass substrate are used in order to increase mass productivity. Each is formed. Then, a so-called multi-cavity means for dividing the glass substrate in correspondence with each display panel is employed.

  As described above, a scribe line is formed on the substrate using a disk-shaped diamond cutter as one means for dividing the large glass substrate to obtain individual display panels, and along the scribe line. By applying external force, it is possible to adopt a means for individually dividing.

  FIG. 1 schematically shows such a state. Reference numeral 1 in FIG. 1 (A) denotes a disk-shaped diamond cutter that rotates in the direction of arrow a, and this cutter 1 is a glass substrate as a substrate to be processed. 2 is moved in the direction of the arrow b along the planned dividing line. As a result, the surface of the glass substrate 2 is cut into a linear shape by the diamond cutter 1, whereby a scribe line 2 a is formed on the planned cutting line of the glass substrate 2. Then, as shown in FIG. 1B, by applying an external force in the direction of arrow c with the scribe line 2a as a boundary, the substrate can be divided to obtain individual display panels.

  Further, as another means for dividing a glass substrate as a substrate to be processed, a method using laser light has been proposed. FIG. 2 schematically shows an example thereof, which is provided with a lens 3 as an optical means for condensing laser light to form a focal point. By moving the optical means in the direction of arrow d, glass is provided. A scribe line 2 a is formed on the planned cutting line on the surface of the substrate 2. Then, as in the example shown in FIG. 1B, by applying an external force in the direction of arrow c with the scribe line 2a as a boundary, the substrate is divided to obtain individual display panels.

  In the case of using the laser beam shown in FIG. 2, by adopting a higher-power laser beam, the melt cutting action by the laser beam is promoted, and the substrate is immediately divided along the division line. Means are also conceivable.

  Further, as another means for dividing a glass substrate as a substrate to be processed, a method using a laser beam and a cooling medium in combination has been proposed. FIG. 3 schematically shows an example thereof, which is also provided with a lens 3 as optical means for condensing laser light to form a focal point, and by moving the optical means in the direction of arrow d, A part of the substrate is heated by a laser beam along a predetermined dividing line on the surface of the glass substrate 2.

  Immediately after that, by discharging a cooling medium such as water to the heated portion as indicated by an arrow e, the substrate can be divided by generating a crack due to thermal strain stress in the heated portion. .

As described above, for example, for a glass substrate, the means for dividing the substrate according to the embodiment described in FIGS. 1 to 3 is disclosed in Patent Document 1 and Patent Document 2 shown below.
Japanese Patent Application Laid-Open No. 2002-346995 JP 2004-042423 A

  By the way, according to the glass substrate dividing means using the diamond cutter 1 as shown in FIG. 1, microcracks (minute chips) are likely to occur in the cut grooves (scribe lines 2a) cut by the cutter 1, There arises a problem that glass powder is generated by cutting and adheres to the glass substrate. Further, since the diamond cutter 1 has a lifetime, there is a problem in maintenance that it is necessary to periodically exchange and adjust the diamond cutter 1.

  Further, when the diamond cutter 1 is used, the scribe line 2a generally has to be formed linearly, and it is impossible to divide the substrate with a free curve. In addition, there is a problem that innumerable scratches are left on the dividing end surface of the substrate in the dividing (breaking) process after the scribe line is formed.

  On the other hand, according to the glass substrate dividing means using laser light as shown in FIG. 2, the above-mentioned several problems can be solved, but the dividing (breaking) process after the scribe line is formed. However, the problem that innumerable scratches are left on the cut end face of the substrate is similarly left. Further, when the power of the laser beam is increased in order to increase the depth of the groove in the scribe line 2a, there is a problem that microcracks are generated at both side portions of the groove.

  Further, in the glass substrate dividing means shown in FIG. 2, when the high-power laser beam is used to promote the melt cutting action by the laser beam, the substrate is immediately divided along the planned dividing line. In this case, under the influence of high-power laser light, there may be a problem that the periphery of the cut portion is thermally affected and stress is applied to TFTs already formed on the glass substrate surface.

  Further, as shown in FIG. 3, the substrate dividing means due to the thermal strain stress by the combined use of the laser beam and the cooling medium requires a cooling mechanism, which complicates the apparatus. Further, since the dividing direction is determined by the positional relationship between the focal position of the laser beam and the cooling mechanism, it is difficult to perform a reciprocating operation for dividing or an oblique dividing process. In addition, it is difficult to adjust the balance between heat administration by laser light and the degree of cooling, and there is a problem that the cutting performance due to thermal strain stress is unstable.

  The present invention has been made paying attention to the conventional problems as described above, and does not leave a microcrack or glass powder at the parting position, and can be used for stable parting performance of the substrate or by using laser light. It is an object of the present invention to provide a substrate processing method and a processing apparatus capable of forming a groove.

  A preferred first aspect of the substrate processing method according to the present invention made to solve the above-described problems is that, as described in claim 1, the laser beam is irradiated along the surface of the line to be cut of the substrate to be processed. Thus, there is provided a substrate processing method for dividing the substrate or forming a dividing groove in the substrate, wherein the focal position of the laser beam is relatively reciprocated in the thickness direction of the substrate. The method is characterized in that the substrate is relatively moved along a planned dividing line of the substrate.

  Moreover, the 2nd preferable aspect in the processing method of the board | substrate concerning this invention is a parting | dividing said board | substrate by irradiating a laser beam along the surface of the parting plan line of a to-be-processed substrate as described in Claim 3. Alternatively, a substrate processing method for forming a dividing groove on the substrate, wherein the focal position of the laser beam is relatively moved along a division line of the substrate, and at the same time in the surface direction of the substrate. It is characterized in that it is reciprocated relatively in a direction orthogonal to the planned dividing line.

  Furthermore, a preferable third aspect of the substrate processing method according to the present invention is that, as described in claim 5, the substrate is divided by irradiating a laser beam along the surface of the line to be divided of the substrate to be processed. Alternatively, a substrate processing method for forming a dividing groove in the substrate, wherein the focal position of the laser light is reciprocated relatively in the plate thickness direction of the substrate, and at the same time in the surface direction of the substrate. The present invention is characterized in that it is relatively reciprocated in a direction perpendicular to the planned dividing line, and at the same time, is relatively moved along the planned dividing line of the substrate.

  On the other hand, a first preferred embodiment of the substrate processing apparatus according to the present invention, which has been made to solve the above-mentioned problems, is the laser beam along the surface of the line to be cut of the substrate to be processed as described in claim 9. Is a substrate processing apparatus that divides the substrate or forms a groove for dividing in the substrate, a laser light generating means for generating laser light, and a laser light from the laser light generating means. Optical means for focusing to form a focal point, and relatively moving the focal position of the laser beam reciprocally in the thickness direction of the substrate, and at the same time, relatively moving along the planned dividing line of the substrate It is characterized by being configured.

  According to a second preferred embodiment of the substrate processing apparatus of the present invention, the substrate is divided by irradiating a laser beam along the surface of the line to be divided of the substrate to be processed as defined in claim 11. Alternatively, a substrate processing apparatus for forming a dividing groove in the substrate, wherein the laser light generating means for generating laser light and the optical means for forming a focal point by condensing the laser light from the laser light generating means The focal position of the laser beam is relatively moved along the planned division line of the substrate, and at the same time, is relatively reciprocated in the direction of the surface of the substrate and perpendicular to the planned division line. It is configured as described above.

  Furthermore, in a preferred third embodiment of the substrate processing apparatus according to the present invention, as set forth in claim 13, the substrate is divided by irradiating a laser beam along the surface of the line to be divided of the substrate to be processed. Alternatively, a substrate processing apparatus for forming a dividing groove in the substrate, wherein the laser light generating means for generating laser light and the optical means for forming a focal point by condensing the laser light from the laser light generating means The focal position of the laser beam is relatively reciprocated in the plate thickness direction of the substrate, and at the same time, the laser beam is reciprocated relatively in the surface direction of the substrate and in a direction orthogonal to the planned dividing line. And at the same time, the substrate is relatively moved along the planned dividing line of the substrate.

Hereinafter, a processing apparatus for realizing the above-described substrate processing method according to the present invention will be described based on embodiments shown in the drawings. FIG. 4A schematically shows the first embodiment, and reference numeral 11 indicates a laser oscillator as laser light generating means. The laser oscillator 11 generates laser light 12 by pulse oscillation of 20 kHz to 50 KHz, for example, and is selected to correspond to the absorption wavelength of the material constituting the substrate to be processed such as CO ₂ laser or YAG laser. The laser beam is configured such that its optical path is bent vertically downward through a vent mirror 13 constituting the optical means 15, and the laser beam 12 is collected and incident on a lens 14 that forms a focal point S. ing.

  On the other hand, a processing substrate mounting table 16 is disposed immediately below the optical means 15, and a glass substrate 17 as a processing substrate is placed on the table 16. In addition, the glass substrate 17 shown to a figure is shown in the state fractured | ruptured along the dividing line of a board | substrate for convenience of explanation. The optical means 15 including the bent mirror 13 and the lens 14 is moved along the X direction, which is the planned dividing line of the substrate 17, while moving the lens 14 on the substrate 17. An operation of reciprocating in the thickness direction (Z-Z ′ direction) is performed.

  In this case, the substrate to be processed is a glass substrate, and as described above, by using a pulsed laser beam of 20 kHz to 50 KHz, a dent (scribe line) having a depth of several tens of microns by projection of 10 to 100 pulses. Can be formed on a glass substrate. The operation of reciprocating the focal point S in the plate thickness direction (Z-Z ′ direction) is preferably set to about 1/10 to / 100 of the pulse oscillation frequency.

  FIG. 4B is a schematic diagram showing an enlarged part of the glass substrate 17 processed by the configuration shown in FIG. As described above, the position of the focal point S of the laser beam moves in the X direction, which is a line to be divided of the substrate 17, and simultaneously operates so as to reciprocate in the plate thickness direction of the substrate 17, that is, the ZZ ′ direction. A groove 17a for dividing the substrate by the thermal energy of the laser light is formed in the planned dividing line. Moreover, the groove 17a can be formed from the substrate surface to a deeper position by reciprocating the focal point S in the ZZ ′ direction.

  According to the scribe line forming means having the above-described action, the dividing groove 17a can be formed to a deeper position while using a laser beam having a relatively low power. The degree of leaving cracks and the like can be reduced. In addition, in the process of dividing (breaking) the substrate after the formation of the groove 17a, it is possible to reliably reduce the incidence of defects that cause cracks in parts other than the line to be divided, and innumerable to the dividing end surface of the substrate. The degree of leaving scratches can also be reduced.

  The above description is based on the premise that a groove for cutting is formed along the planned cutting line of the substrate and then the substrate is cut. According to the apparatus shown in FIG. By further increasing the stroke of the reciprocating movement of the focal point S of the laser beam in the plate thickness direction (Z-Z ′ direction), the substrate to be processed can be immediately divided.

  In the embodiment shown in FIG. 4, the optical means 15 including the vent mirror 13 and the lens 14 is moved in the X direction, and the lens 14 is moved in the Z direction. Even if the optical means 15 is fixed and the table 16 on which the substrate to be processed is mounted is moved in the X and Z directions, the same effect can be obtained.

  Next, FIG. 5 schematically shows a second embodiment according to the present invention. In FIG. 5, parts that perform the same functions as those shown in FIG. 4 are denoted by the same reference numerals, and therefore detailed description thereof is omitted. In the embodiment shown in FIG. 5, the optical means 15 including the vent mirror 13 and the lens 14 is moved along the planned dividing line of the substrate, and at the same time, in the surface direction of the substrate and orthogonal to the planned dividing line. It is comprised so that it may reciprocate in the direction to do.

  That is, as shown in FIG. 5A, the optical means 15 including the vent mirror 13 and the lens 14 moves the position of the focal point S of the laser light along the X direction that is a planned dividing line of the substrate 17. Then, an operation of reciprocating in the surface direction of the substrate and in a direction (YY ′ direction) perpendicular to the planned dividing line is performed.

  FIG. 5B illustrates the movement operation of the focal point S described above, and this is shown in an enlarged view of the glass substrate 17 as the substrate to be processed, as viewed from above along the line to be cut (X direction). ing. As described above, the operation of reciprocating in the Y-Y 'direction is repeated at the same time as the position of the focal point S of the laser beam moves in the X direction, so that the substrate is divided by the thermal energy of the laser beam in the planned dividing line. The grooves 17a are processed so as to gradually become deeper.

  In the scribe line forming means having the above-described action, the dividing groove 17a can be formed to a deeper position while using a laser beam having a relatively small power, so that the embodiment shown in FIG. The same effect can be obtained.

  In the embodiment shown in FIG. 5, the optical means 15 including the bent mirror 13 and the lens 14 is configured to move in the X and Y directions. Even if the table 16 on which the substrate to be processed is mounted is configured to move in the X and Y directions, the same effect can be obtained.

  In the substrate processing apparatus according to the present invention, a configuration in which the laser beam focal point movement operations shown in FIGS. 4 and 5 described above are combined can be suitably employed. That is, the optical means 15 including the vent mirror 13 and the lens 14 is moved in the X direction along the planned dividing line of the substrate as shown in FIG.

  At this time, as shown in FIG. 4, the focal position of the laser beam is reciprocated in the plate thickness direction (Z direction) of the substrate, and at the same time, in the plane direction of the substrate as shown in FIG. An operation of reciprocating in the direction perpendicular to the line (Y direction) is accompanied. By executing such a complex operation, a groove for dividing the substrate can be effectively formed. Even in this case, the same effect can be obtained even if the optical means is fixed and the table on which the substrate to be processed is mounted is moved in the X, Y, and Z directions.

  In the above description, a glass substrate is taken as an example of a substrate to be processed. However, in the above-described processing apparatus according to the present invention, it is suitable for cutting a ceramic substrate, a sapphire substrate, a semiconductor wafer, etc. in addition to the glass substrate. Can be adopted.

It is a schematic diagram explaining the conventional parting means of a board | substrate using a diamond cutter. It is a schematic diagram explaining the conventional parting means of a board | substrate using a laser beam. It is a schematic diagram explaining the conventional parting means of the board | substrate by the thermal strain stress which used a laser beam and a cooling medium together. It is the schematic diagram which showed 1st Embodiment in the processing apparatus of the board | substrate concerning this invention. It is the schematic diagram which similarly showed 2nd Embodiment.

Explanation of symbols

11 Laser oscillator (laser light generating means)
12 Laser light 13 Vent mirror 14 Lens 15 Optical means 16 Table 17 Substrate 17a Groove (scribe line)
S Focus of laser light

Claims (16)

A substrate processing method for dividing a substrate or forming a dividing groove in the substrate by irradiating a laser beam along a surface of a division planned line of the substrate to be processed,
A method of processing a substrate, wherein the focal position of the laser beam is reciprocated relatively in the plate thickness direction of the substrate, and at the same time, is relatively moved along a predetermined dividing line of the substrate.   2. The optical means for condensing the laser light to form a focal point is reciprocated in the thickness direction of the substrate and simultaneously moved along a planned dividing line of the substrate. Method of processed substrate. A substrate processing method for dividing a substrate or forming a dividing groove in the substrate by irradiating a laser beam along a surface of a division planned line of the substrate to be processed,
The focal position of the laser beam is relatively moved along the planned dividing line of the substrate, and at the same time, is relatively reciprocated in the surface direction of the substrate and in a direction perpendicular to the planned dividing line. Substrate processing method.   The optical means for condensing the laser light to form a focal point is moved along the planned dividing line of the substrate, and at the same time, reciprocated in the surface direction of the substrate and in a direction orthogonal to the planned dividing line. The substrate processing method according to claim 3. A substrate processing method for dividing a substrate or forming a dividing groove in the substrate by irradiating a laser beam along a surface of a division planned line of the substrate to be processed,
The focal position of the laser beam is relatively reciprocated in the thickness direction of the substrate, and at the same time, is relatively reciprocated in the surface direction of the substrate and in a direction orthogonal to the division line, and at the same time, the substrate A method for processing a substrate, wherein the substrate is relatively moved along a predetermined dividing line.   The optical means for condensing the laser beam to form a focal point is reciprocated in the thickness direction of the substrate, and at the same time, reciprocated in the direction of the surface of the substrate and in the direction perpendicular to the division line, The substrate processing method according to claim 5, wherein the substrate is moved along a division line of the substrate.   7. The substrate processing method according to claim 1, wherein pulsed laser light is used.   The substrate processing method according to any one of claims 1 to 7, wherein the substrate is a glass substrate, a ceramic substrate, a sapphire substrate, or a semiconductor wafer. A substrate processing apparatus that divides the substrate or forms a dividing groove in the substrate by irradiating a laser beam along the surface of the division line of the substrate to be processed,
Laser light generating means for generating laser light, and optical means for focusing the laser light from the laser light generating means to form a focal point,
An apparatus for processing a substrate, wherein the focal position of the laser beam is relatively reciprocated in the thickness direction of the substrate, and at the same time, is relatively moved along a predetermined dividing line of the substrate.   The substrate processing apparatus according to claim 9, wherein the optical unit is configured to reciprocate in the plate thickness direction of the substrate and at the same time to move along the planned dividing line of the substrate. A substrate processing apparatus that divides the substrate or forms a dividing groove in the substrate by irradiating a laser beam along the surface of the division line of the substrate to be processed,
Laser light generating means for generating laser light, and optical means for focusing the laser light from the laser light generating means to form a focal point,
The focal position of the laser beam is relatively moved along the planned dividing line of the substrate, and at the same time, is relatively reciprocated in the surface direction of the substrate and in a direction perpendicular to the planned dividing line. A substrate processing apparatus.   12. The optical device according to claim 11, wherein the optical means is moved along a planned dividing line of the substrate, and at the same time, is reciprocated in the surface direction of the substrate and in a direction perpendicular to the planned dividing line. The described substrate processing apparatus. A substrate processing apparatus that divides the substrate or forms a dividing groove in the substrate by irradiating a laser beam along the surface of the division line of the substrate to be processed,
Laser light generating means for generating laser light, and optical means for focusing the laser light from the laser light generating means to form a focal point,
The focal position of the laser beam is relatively reciprocated in the thickness direction of the substrate, and at the same time, is relatively reciprocated in the surface direction of the substrate and in a direction orthogonal to the division line, and at the same time, the substrate An apparatus for processing a substrate, wherein the substrate processing apparatus is configured to move relative to each other along a predetermined dividing line.   The optical means is reciprocated in the thickness direction of the substrate, and at the same time, reciprocated in the surface direction of the substrate and in a direction perpendicular to the planned dividing line, and simultaneously moved along the planned dividing line of the substrate. 14. The substrate processing apparatus according to claim 13, wherein the substrate processing apparatus is configured as follows.   The substrate processing apparatus according to claim 9, wherein the laser light generating unit is configured to generate laser light by pulse oscillation.   The substrate processing apparatus according to any one of claims 9 to 15, wherein the substrate is a glass substrate, a ceramic substrate, a sapphire substrate, or a semiconductor wafer.

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