JP2000237889A - Laser beam machining method and equipment therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam machining method and equipment therefor capable of high machining, hardly generating thermal strains and micro cracks and reducing thermal damage. SOLUTION: When laser beam machining an object 10 to be machined, by conducting rapid heating by a CO laser beam 3-4 and rapid cooling by a rapid cooling agent in adjoining, rapid cooling of the object 10 to be machined can be done without using water. As a result, high speed machining is made possible, thus, thermal strains as well as micro cracks are hardly generated, thermal damage is reduced as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for processing a workpiece, and more particularly to a laser processing method and an apparatus therefor.

[0002]

_2. Description of the Related Art In recent years, CO ₂ lasers, YAG lasers, or excimer lasers have been used to cut metal materials and non-metal materials, to form grooves and holes, to weld, and to further modify the material surface. Technology is gradually being put to practical use.

FIGS. 13 and 14 are conceptual diagrams of a conventional laser processing method.

[0004] A laser processing method shown in FIG. 13 applies a CO ₂ laser beam 5 to a substrate (metal or non-metallic material substrate) 51.
The substrate 51 is cut by irradiating 0. That is, the CO ₂ laser beam 50 is condensed by the condensing lens 56, and the condensed CO ₂ laser beam 50-1 having a small spot diameter is transferred to the substrate 51 moving in the arrow 55 direction.
Of the substrate 51 while forming a cutting groove 57 while irradiating the surface of the substrate 51 and also blowing the assist gas 54 onto the surface of the substrate 51.
Is divided into two, which is a so-called evaporative cutting method. In this method, the focused CO ₂ laser beam 50-1 is used.
Is irradiated so as to focus on the surface of the substrate 51 with a beam spot diameter of about 100 μm.
_{2. The} cutting groove 57 is formed while evaporating the material by the thermal energy of the laser beam 50-1.

In the laser processing method shown in FIG. 14, the surface of a moving substrate 51 is irradiated with a CO ₂ laser beam 50-1 having a beam spot diameter of 500 μm or more.
A crack 58 is generated by thermal stress in the
This is a so-called splitting method in which the substrate 51 is split into two by extending along the irradiation locus of the O ₂ laser beam 50-1.

However, the above-mentioned two conventional laser processing methods include 1) a low processing speed, 2) a heat-strained layer or a microcrack is easily generated for non-metallic materials, and 3) formation on a substrate. There is a problem that the electronic circuit, the optical circuit, the electric wiring and the like are easily damaged by heat.

Therefore, as a laser processing method for solving the above problems, the present inventor has previously proposed a method shown in FIG. 15 (Japanese Patent Application No. 7-168912 and Japanese Patent Application Laid-Open No. 9-19787). This is because water 52 is sprayed in the direction of arrow 52-1 behind the CO ₂ laser beam 50-1 irradiated on the substrate 51 to rapidly cool the substrate surface heated by the CO ₂ laser beam 50-1. Is the way. FIG. 15 is an explanatory diagram of the optical processing method on which the present invention is based.

[0008]

By the way, when the laser processing method shown in FIG. 15 is used, the processing speed can be improved, the occurrence of thermal strain and micro cracks can be reduced, and the laser formed on the substrate can be reduced. It has been found that thermal damage to electronic circuits and optical circuits can be reduced.

However, the method shown in FIG. 15 has the following problems.

(1) Since it is a wet cooling method, a drying step is required after processing, which is expensive.

(2) The characteristics of an electronic circuit, an optical circuit, and the like formed on the substrate are changed or deteriorated by getting wet with water.

(3) Particles tend to remain on the substrate because of the wet type.

(4) Since the cooling is performed by water, the rapid cooling effect is small.

An object of the present invention is to solve the above-mentioned problems, to provide a laser processing method and apparatus which can perform high-speed processing, hardly generate thermal distortion and microcracks, and have small thermal damage. .

[0015]

In order to achieve the above object, a laser processing method of the present invention irradiates a laser beam spot on a surface of a workpiece moving at a constant speed,
By spraying a quenching agent behind the portion heated by the irradiation of the laser beam spot, rapid heating and rapid cooling are performed side by side.

Further, according to the laser processing method of the present invention, a surface of a workpiece moving at a constant speed is irradiated with a laser beam spot, and a quenching agent and a desired gas are provided behind a portion heated by the irradiation of the laser beam spot. Spraying, rapid heating and rapid cooling are performed side by side.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable that the laser beam spot has a substantially circular or substantially elliptical cross section or a linear shape having a width W and a length L.

In the laser processing method of the present invention, in addition to the above configuration, it is preferable that the quenching agent is sprayed in a substantially elliptical shape so that the major axis is parallel to the processing direction.

In the laser processing method of the present invention, in addition to the above-described structure, it is preferable that the quenching agent is transported by a Freon gas which does not destroy the ozone layer.

In addition to the above configuration, the laser processing method of the present invention preferably uses a CO ₂ laser beam as a laser beam spot.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable to use a nonmetallic material substrate as the workpiece.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable that the quenching agent is obliquely sprayed onto the surface of the workpiece from the nozzle outlet having an inner diameter of 1 mmφ or less through the introduction pipe.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable that the laser beam spot and the quenching agent applied to the surface of the workpiece pass through a nozzle whose inner diameter of the ejection port is tapered.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable that the distance between the center position of the laser beam spot and the center position where the quenching agent is sprayed is at least 100 μm.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable that the ejection port of the nozzle is formed in an elliptical shape long in the processing direction.

In addition to the above configuration, in the laser processing method of the present invention, it is preferable that the processing of the workpiece is performed in a box provided with forced exhaust equipment.

A laser processing apparatus according to the present invention comprises a laser oscillator, an optical system for converging a parallel laser beam from the laser oscillator and irradiating the laser beam to a workpiece, and a laser beam spot irradiating the surface of the workpiece. It is provided with a spraying means for transporting and spraying a quenching agent to the vicinity, and a stage for moving the workpiece.

In addition to the above configuration, in the laser processing apparatus of the present invention, it is preferable that the laser beam spot and the quenching agent pass through a nozzle that has a substantially elliptical and tapered tapered outlet.

The laser processing apparatus according to the present invention comprises a laser oscillator, an optical system for converging a parallel laser beam from the laser oscillator and irradiating the laser beam to the workpiece, and a laser beam spot irradiating the surface of the workpiece. It is provided with a spraying means for conveying and blowing a quenching agent together with a desired gas to the vicinity, and a stage for moving a workpiece.

In addition to the above configuration, in the laser processing apparatus of the present invention, it is preferable that the laser beam spot, the desired gas, and the quenching agent pass through a nozzle having a substantially elliptical and tapered nozzle.

In addition to the above configuration, in the laser processing apparatus of the present invention, it is preferable that the optical system converts the cross-sectional shape of the laser beam spot irradiated on the surface of the workpiece into a substantially circular, substantially elliptical or substantially linear shape.

In addition to the above configuration, in the laser processing apparatus of the present invention, it is preferable that the processing of the workpiece is performed in a box provided with a forced exhaust equipment.

According to the present invention, when the workpiece is laser-processed, rapid heating of the workpiece is performed without using water by performing rapid heating by a laser and rapid cooling by a quenching agent side by side. be able to. In particular, by blowing assist gas (N ₂ , O ₂ , air, etc.) onto the laser irradiation surface, the temperature rise of the workpiece can be suppressed even slightly, and as a result, quenching by the heat of vaporization due to the spray of the quenching agent The effect can be enhanced. Further, since vaporization can be further promoted, rapid cooling can be performed in a shorter time. As a result, high-speed processing can be performed, thermal distortion and microcracks are less likely to occur, and thermal damage is reduced.

[0034]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a conceptual diagram showing an embodiment of an apparatus to which the laser processing method of the present invention is applied.

[0036] This device, while irradiating the CO ₂ laser beam on the surface of the substrate 10 to be moved in one direction at a desired speed, rapid heating while blowing quenching agent behind the irradiated CO ₂ laser beam, rapid cooling In this way, the substrate 10 as a workpiece is subjected to evaporative cutting, division by cutting, digging of slits and shallow grooves, and drilling.

This device comprises a laser oscillator 1 and parallel laser beams 3-1, 3-2, 3-3 from the laser oscillator 1.
Optical system for condensing and irradiating the substrate 10 with the quenching agent, and a quenching agent introduction pipe 8 and a quenching agent supply as blowing means for conveying and blowing the quenching agent near the laser beam spot 3-4 irradiated on the surface of the substrate 10 An apparatus 7 and an XYZθ stage (hereinafter referred to as “stage”) 11 for rotating and moving a substrate 10
It is composed of 2 is a total reflection mirror 4-1 inside,
4-2 is a hood for guiding the parallel laser beams 3-1, 3-2, 3-2 emitted from the CO ₂ laser oscillator 1 to the condenser lens 5.

A non-metallic material (quartz glass,
Multi-component glass, ceramics, sapphire, LiNb
O ₃ , quartz, LiTaO ₅ , Si with an oxide film, crystallized glass, etc.) and metal materials can be used. The substrate 10 is fixed on a movable portion 12 having a substrate fixing function. The movable portion 12 is attached to a stage 11 that can move in the X-axis, Y-axis, Z-axis, and θ-axis directions. (Not shown), it is moved at a desired speed in the direction of arrow 13. The surface of the substrate 10 has a CO ₂ laser beam 3-4
And a quenching agent is also sprayed.

The CO ₂ laser beam 3-4 guides the parallel laser beam 3-1 emitted from the CO ₂ laser oscillator 1 to the condenser lens 5 through the total reflection mirrors 4-1 and 4-2, and collects the collimated laser beam 3-1. The laser beam is focused by the lens 5.

CO ₂ laser beams 3-1, 3-2, 3-
Numerals 3, 3-4 propagate in the hood 2, exit from the tip of the nozzle 6, and irradiate the surface of the substrate 10. On the surface of the substrate 10 heated by the CO ₂ laser beam 3-4, the quenching agent guided from the quenching agent supply device 7 propagates in the quenching agent introduction pipe 8 in the direction of arrow 9 to heat the substrate 10. Sprayed on the surface.

Examples of the quenching agent include Freon gas (hydrofluorocarbon, trade name: HF) which does not destroy the ozone layer.
C134a, hydrochloroalkane, trade name HFA1
34a) are preferred. When these quenching agents are used, a gas having a temperature of -30 ° C to -55 ° C can be instantaneously blown onto the heated surface.

The portion of the surface of the substrate 10 immediately after the heating is completed only by spraying the quenching agent is instantaneously-
An instant freezing spray (trade name: minus 96, Freeze It 2000, etc.) that cools from 60 ° C. to about −50 ° C. may be used.

By spraying the quenching agent, the heat of vaporization is used to activate, for example, an evaporative cutting portion or a crack generating portion due to the cracking, thereby providing an effect of increasing the cutting speed and the crack growth speed. Moreover, since the quenching agent is sprayed onto the substrate 10 in a dry state and in a clean state, it is possible to prevent particles from adhering to the substrate 10 and to adhere impurities (dust, particles, etc.) to the condenser lens 5. It also has a preventive action.

The quenching agent introduction pipe 8 is provided only on one side of the nozzle 6 so that the quenching agent can be sprayed on a portion immediately after the surface of the substrate 10 has been heated by laser irradiation.

The CO ₂ laser oscillator 1 has a wavelength of 9.1 μm.
Those that oscillate in the range of m to 11.3 μm can be used. Further, the CO ₂ laser oscillator 1 which oscillates at several wavelengths or one wavelength from the above wavelength range may be used.

FIG. 2A is a side sectional view showing another embodiment near the nozzle used in the laser processing method of the present invention, and FIG. 2B is a sectional view of the nozzle shown in FIG. 2A. It is a bottom view.

The CO ₂ laser beam 3 shown in FIG.
The focus of 4 is set so as to be connected to the surface 22 of the substrate 10, and the quenching agent that has proceeded in the direction of arrow 9 through the quenching agent introduction pipe 8 attached to the nozzle 6 at an angle α is applied to the substrate 10.
Is set so as to be sprayed onto the surface 22 at a position separated by a distance d from the focal position of the CO ₂ laser beam 3-4.

Here, the beam spot diameter at the focal point of the CO ₂ laser beam 3-4 is usually 100 μm to 200 μm.
The value of the distance d is at least 100
A value larger than μm is preferred.

The shape of the nozzle 14 of the nozzle 6 is shown in FIG.
As shown in FIG. 2, if the elliptical shape is used, the rapid heating portion and the rapid cooling portion on the surface 22 of the substrate 10 can be adjacent to each other. Distortion and micro cracks can be suppressed quickly. Further, thermal damage to electronic circuits and optical circuits formed on the substrate 10 can be prevented.
Further, by passing through the rapid heating and rapid cooling processes, cracks due to thermal stress are promoted.
Cutting speed and cutting speed can be increased. Therefore,
The value of the interval d is preferably smaller. However, when the value of the interval d is 100 μm or less, the temperature of the heating portion irradiated with the laser is lowered.

FIG. 3 is a side sectional view showing another embodiment near the nozzle used in the laser processing method of the present invention.

This is to irradiate the surface 22 of the substrate 10 with a non-focused laser beam of a CO ₂ laser beam 3-4. In other words, the CO ₂ laser beam shown in FIG. 2 is suitable for evaporating and cutting a nonmetallic material or a metal material, performing groove processing or slitting by evaporation, or performing hole drilling. The case of the CO ₂ laser beam shown in FIG. 3 is suitable for cutting a nonmetallic material.

Therefore, on the surface 22 of the substrate 10, the diameter of the irradiation surface 15 of the CO ₂ laser beam 3-4 is set to a value larger than several hundred μm. Further, the area of the spray surface 16 of the quenching agent to the surface of the substrate 10 also increases. In this configuration,
It is also suitable for cleaving quartz-based glass substrates, multi-component glass substrates, ceramic substrates, sapphire substrates, etc., at higher speeds, in a dry process, in a clean atmosphere, without thermal distortion or microcracks, and without thermal damage. Processing can be performed with less.

FIG. 4 is an explanatory view showing another embodiment of the laser processing method of the present invention.

In this method, the substrate 10 made of a nonmetallic material moving at a desired speed in the direction of arrow 13 is irradiated onto the surface of the substrate 10 at the time of cutting (or evaporating and cutting) along a predetermined cutting (or evaporating and cutting) line 17. ₂ shows the shape of the CO ₂ laser beam irradiation surface 15 and the shape of the quenching agent spraying surface 16 to be sprayed. The shape of the irradiation surface 15 of the CO ₂ laser beam is substantially circular, whereas the shape of the spray surface 16 of the quenching agent sprayed behind the heated portion is formed into an elongated elliptical shape. Promote 18 more. Note that the center of the CO ₂ laser beam irradiation surface 15 and the center of the quenchant spraying surface 16 are located on the expected cutting (or evaporating) line.

FIG. 5 is an explanatory view showing another embodiment of the laser processing method of the present invention.

In this embodiment, the shape of the irradiation surface 15 of the CO ₂ laser beam is converted into an elliptical shape so that the surface of the substrate 10 is irradiated, and the processing is performed at a higher speed than the embodiment shown in FIG. be able to.

FIG. 6 is an explanatory view showing another embodiment of the laser processing method of the present invention.

In this method, the shape of the CO ₂ laser beam is further converted into a linear light beam to irradiate the surface of the substrate 10. This linear light beam can be realized by providing, for example, a cylindrical rod (or circular tube) of ZnSe after the condenser lens. The length L of the light beam and the width W of the light beam are defined as the distance between the condenser lens and the cylindrical rod (or the cylindrical tube), the outer diameter of the cylindrical rod (or the cylindrical tube), and the distance between the cylindrical rod (or the cylindrical tube) and the substrate 10. It can be controlled by the distance to the surface, the diameter of the parallel laser beam incident on the condenser lens, and the like. With such a linear light beam, higher-speed processing can be realized than in the case shown in FIG.

FIG. 7 is a conceptual diagram showing another embodiment of the apparatus to which the laser processing method of the present invention is applied.

In this apparatus, the substrate being processed is covered with a box 19 together with the nozzle, and the inside of the box 19 is evacuated by an exhaust duct 2.
By performing forced exhaust by the forced exhaust device 21 through 0, processing is performed in a cleaner and dry process.

FIG. 8 is a conceptual diagram showing another embodiment of the apparatus to which the laser processing method of the present invention is applied.

This device comprises a laser oscillator 1 and parallel laser beams 3-1, 3-2, 3-3 from the laser oscillator 1.
Optical system for condensing light and irradiating the substrate 10 with the gas introduction pipe 3
Assist gas flowing in the direction of arrow 31 through
A quenching agent introducing pipe 8 and a quenching agent supply device 7 as blowing means for conveying and blowing a quenching agent near the laser beam spot 3-4 irradiated on the surface of the substrate 10; Stage 1 for rotating and moving 10
1 and 1.

The surface of the substrate 10 is irradiated with a CO ₂ laser beam 3-4 maintained in an assist gas atmosphere, and a quenching agent is also sprayed.

CO ₂ laser beams 3-1, 3-2, 3-
Numerals 3, 3-4 propagate in the hood 2, exit from the tip of the nozzle 6, and irradiate the surface of the substrate 10. The assist gas flows in the gas introduction pipe 30 in the direction of arrow 31 and
To reduce the ambient temperature of the surface of the substrate 10 and its surroundings. On the surface of the substrate 10 heated by the CO ₂ laser beam 3-4, the quenching agent guided from the quenching agent supply device 7 propagates in the quenching agent introduction pipe 8 in the direction of arrow 9 to heat the substrate 10. Sprayed on the surface.

The quenching agent supply device 7 and the quenching agent introduction pipe 8
An electromagnetic valve (not shown) is provided between the control unit and the electronic control unit. By electrically controlling the electromagnetic valve, the injection and stop of the quenching agent can be performed.

The smaller the inner diameter of the nozzle injection port of the quenching agent introduction pipe 8, the more rapidly the quenching agent can be injected. Its inner diameter is 1 mmφ or less, preferably 0.5 mmφ or less.

FIG. 9A is a side sectional view showing another embodiment near the nozzle used in the laser processing method of the present invention, and FIG. 9B is a sectional view of the nozzle shown in FIG. 9A. It is a bottom view.

The CO ₂ laser beam 3 shown in FIG.
The focus of 4 is set so as to be connected to the surface 22 of the substrate 10, and the quenching agent that has proceeded in the direction of arrow 9 through the quenching agent introduction pipe 8 attached to the nozzle 6 at an angle α is applied to the substrate 10.
Is set so as to be sprayed onto the surface 22 at a position separated by a distance d from the focal position of the CO ₂ laser beam 3-4.

By guiding the assist gas flowing in the direction of arrow 31 into the nozzle 6, the temperature of the surface 22 of the substrate 10 and its surroundings can be lowered even a little, so that the quenching effect by spraying the quenching agent can be promoted. .

Here, the beam spot diameter at the focal point of the CO ₂ laser beam 3-4 is usually 100 μm to 200 μm.
The value of the distance d is at least 100
A value larger than μm is preferred.

As shown in FIG. 3B, the shape of the ejection ports 14-1 and 14-2 of the nozzle 6 is such that one of the ejection ports 14-1 flows with the CO ₂ laser beam 3-4 in the direction of the arrow 31. It has a large circular shape so that the assist gas can pass through, and the other ejection port 14-2 has a diameter of 0.5 m to increase the ejection pressure.
If a circle with an inner diameter of mφ or less or an elliptical shape is used,
Since the rapid heating portion and the rapid cooling portion on the surface 22 of the substrate 10 can be adjacent to each other, it is possible to quickly suppress thermal distortion and micro cracks that are generated in the rapid heating portion. Further, thermal damage to electronic circuits and optical circuits formed on the substrate 10 can be prevented. Further, by passing through the rapid heating and rapid cooling processes, cracks due to thermal stress are promoted, so that the cutting speed and the cutting speed of the substrate 10 can be increased. Therefore, it is preferable that the value of the interval d is smaller.
However, when the value of the interval d is 100 μm or less, the temperature of the heating portion irradiated with the laser is lowered.

FIG. 10 is a side sectional view showing another embodiment of the vicinity of the nozzle used in the laser processing method of the present invention.

In this case, the surface 22 of the substrate 10 is irradiated with a non-condensing laser beam of the CO ₂ laser beam 3-4. In other words, the CO ₂ laser beam shown in FIG. 2 is suitable for evaporating and cutting a nonmetallic material or a metal material, performing groove processing or slitting by evaporation, or performing hole drilling. The case of the CO ₂ laser beam shown in FIG. 3 is suitable for cutting a nonmetallic material. In this case, since the distance h from the tip of the nozzle to the surface of the substrate 10 becomes large, the quenching agent introduction pipe 8 is separated from the nozzle 6 and arranged near the surface of the substrate 10 as shown in FIG. I have.

FIG. 11 is a side sectional view showing another embodiment near the nozzle used in the laser processing method of the present invention.

The CO ₂ laser beam 3-4, the assist gas flowing in the direction of arrow 31, and the quenching agent flowing in the direction of arrow 9 are passed through a nozzle 6 having a jet outlet with a tapered inner diameter. is there. In this case, there is an effect that the vaporization of the quenching agent is promoted by the assist gas atmosphere.

FIG. 12 is a conceptual diagram showing another embodiment of the apparatus to which the laser processing method of the present invention is applied.

In this apparatus, the substrate being processed is covered with the nozzle 19 together with the nozzle, and the inside of the box 19 is exhausted by the exhaust duct 2.
By performing forced exhaust by the forced exhaust device 21 through 0, processing is performed in a cleaner and dry process.

The present invention is not limited to the above embodiment.

First, in addition to the CO ₂ laser oscillator, a CO laser oscillator, an excimer laser oscillator,
Various laser oscillators such as a YAG laser oscillator and a copper vapor laser oscillator can be used. Further, the laser oscillator may oscillate continuously or pulse. The output power of the laser oscillator is preferably several tens W to several kW.

In the laser processing apparatus shown in FIGS. 1, 7, 8 and 12, C is used without using the total reflection mirror 4-1.
The O ₂ laser oscillator 1 may be installed so as to lie on an extension of the optical axis of the CO ₂ laser beam 3-2.

In the embodiment shown in FIGS. 4 to 6, a scribe line is previously put on the cut (or evaporative cut) scheduled line 17 with a diamond cutter, a laser or the like, and CO is cut along the scribe line. ₍₂₎ Irradiation with a laser beam and spraying of a quenching agent, or spraying using a combination of a quenching agent and an assist gas may be performed. 4 to 6
In the embodiment shown in the above, it is natural that the cutting or the evaporative cutting includes processing the substrate 10 into a lattice so as to divide the substrate 10 into a plurality.

[0082]

The present invention will be described with reference to specific numerical values, but the present invention is not limited thereto.

In the laser processing apparatus shown in FIGS. 1 and 2A and 2B, quartz glass (1 mm thick, 4 inches in diameter) was used as the substrate 10 and the CO (power continuous oscillation) output of 200 W was used. _{(2) The} cutting process is performed with the laser beam 3-4. The quenching agent 134a (trade name) was used as the quenching agent.
As a result, the substrate 10 could be cut at a processing speed of 300 mm / sec. On the other hand, when the quenching agent was not sprayed, the processing speed was 50 mm / sec, and a thermally damaged layer of about 100 μm was formed on the cross section.

Sapphire substrate (1 mm thick, 50 mm thick)
With regard to (corner), it was possible to machine in a half-cut state at a machining speed of 900 mm / sec, and thereafter, it was possible to easily and accurately divide by applying a slight stress. On the other hand, when the quenching agent was not sprayed, the processing speed was reduced to 1/3, and a large number of thermally strained layers were generated at the divided edge portions.

In the laser processing apparatus shown in FIGS. 1 and 7, the quenching agent does not pass through the
May be separated and sprayed behind the heated portion.

In the laser processing apparatus shown in FIGS. 8 and 9A and 9B, quartz glass (thickness: 1 mm, diameter: 4 inches) was used as the substrate 10, and a CO (power continuous oscillation) output of 200 W was used. ₂ N ₂ assist gas is sprayed with a laser beam 3-4 at a pressure of 0.5 kg / cm ² to perform a cutting process. The quenching agent 134a (trade name) was used as the quenching agent. As a result, the substrate 10 was processed at a processing speed of 320 mm / sec.
Was able to be divided. On the other hand, when the quenching agent was not sprayed, the processing speed was 50 mm / sec, and a thermally damaged layer of about 100 μm was formed on the cross section.

Sapphire substrate (1 mm thick, 50 mm thick)
With regard to (corner), it was possible to machine into a half-cut state at a machining speed of 940 mm / sec, and thereafter, it was possible to easily and accurately divide by applying a slight stress. On the other hand, when the quenching agent was not sprayed, the processing speed was reduced to 1/3, and a large number of thermally strained layers were generated at the divided edge portions.

In the laser processing apparatus shown in FIGS. 8 and 12, the quenching agent does not pass through the nozzle 6 but uses the structure shown in FIG. May be sprayed.

As described above, in the laser processing method and apparatus according to the present invention, (1) high-speed processing can be performed by performing dry clean quick heating and rapid cooling side by side, and heat distortion and micro cracks are generated. And thermal damage is extremely small.

(2) Since no drying step is required, cost reduction can be achieved.

(3) Particles adhere to the substrate,
It does not remain.

(4) There is no deterioration in characteristics of electronic circuits, optical circuits, and the like formed on the substrate.

(5) Since no water is used, the processing place can be freely selected.

(6) Since heat distortion and microcracks do not occur, an electronic or optical device that is stable for a long time and has a long life can be realized.

(7) In addition to promoting the vaporization of the quenching agent by spraying the quenching agent and the assist gas together,
The vaporization can be performed in a shorter time by lowering the ambient temperature, and the quenching effect can be further enhanced.

[0096]

In summary, according to the present invention, the following excellent effects are exhibited.

[0097] It is possible to provide a laser processing method and apparatus capable of high-speed processing, less likely to generate thermal distortion and microcracks, and having small thermal damage.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an embodiment of an apparatus to which a laser processing method according to the present invention is applied.

FIG. 2A is a side cross-sectional view showing another embodiment near a nozzle used in the laser processing method of the present invention,
(B) is a bottom view of the nozzle shown in (a).

FIG. 3 is a side sectional view showing another embodiment in the vicinity of a nozzle used in the laser processing method of the present invention.

FIG. 4 is an explanatory view showing another embodiment of the laser processing method of the present invention.

FIG. 5 is an explanatory view showing another embodiment of the laser processing method of the present invention.

FIG. 6 is an explanatory view showing another embodiment of the laser processing method of the present invention.

FIG. 7 is a conceptual diagram showing another embodiment of an apparatus to which the laser processing method of the present invention is applied.

FIG. 8 is a conceptual diagram showing another embodiment of the apparatus to which the laser processing method of the present invention is applied.

FIG. 9A is a side sectional view showing another embodiment near a nozzle used in the laser processing method of the present invention,
(B) is a bottom view of the nozzle shown in (a).

FIG. 10 is a side sectional view showing another embodiment near the nozzle used in the laser processing method of the present invention.

FIG. 11 is a side sectional view showing another embodiment near the nozzle used in the laser processing method of the present invention.

FIG. 12 is a conceptual diagram showing another embodiment of the apparatus to which the laser processing method of the present invention is applied.

FIG. 13 is a conceptual diagram of a conventional laser processing method.

FIG. 14 is a conceptual diagram of a conventional laser processing method.

FIG. 15 is an explanatory diagram of an optical processing method on which the present invention is based.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser oscillator 4-1 and 4-2 Total reflection mirror 5 Condensing lens 6 Nozzle 7 Quenchant supply device 8 Quenchant introduction pipe 10 Substrate (workpiece) 11 XYZθ movement stage (stage)

Claims (18)

[Claims] 1. A rapid heating and rapid cooling by irradiating a laser beam spot on a surface of a workpiece moving at a constant speed and spraying a quench agent behind a portion heated by the irradiation of the laser beam spot. And a laser processing method. 2. A rapid heating by irradiating a laser beam spot on a surface of a workpiece moving at a constant speed and spraying a quench agent together with a desired gas behind a portion heated by the irradiation of the laser beam spot. And performing rapid cooling side by side. 3. The laser processing method according to claim 1, wherein the laser beam spot has a substantially circular or substantially elliptical cross section or a linear shape having a width W and a length L. 4. The cooling agent according to claim 1, wherein the quenching agent is sprayed in a substantially elliptical shape such that a major axis thereof is parallel to a processing direction.
The laser processing method according to any one of the above. 5. The laser processing method according to claim 1, wherein the quenching agent is transported by a Freon gas that does not destroy the ozone layer. 6. The laser beam spot as CO
6. The laser processing method according to claim 1, wherein _two laser beams are used. 7. The laser processing method according to claim 1, wherein a non-metallic material substrate is used as the workpiece. 8. The quenching agent passes through an introduction pipe and has an inner diameter of 1%.
The laser processing method according to any one of claims 1 to 7, wherein the nozzle is blown obliquely onto a surface of the workpiece from a nozzle outlet having a diameter of not more than mmφ. 9. The laser processing according to claim 1, wherein the laser beam spot and the quenching agent applied to the surface of the workpiece pass through a nozzle having an inner diameter of a jet port tapered in a tapered shape. Method. 10. The laser processing method according to claim 1, wherein an interval between a center position of the laser beam spot and a center position to which the quenching agent is sprayed is at least 100 μm. 11. The laser processing method according to claim 9, wherein an ejection port of the nozzle is formed in an elliptical shape long in a processing direction. 12. The processing of the workpiece is performed in a box provided with a forced exhaust system.
The laser processing method according to any one of the above. 13. A laser oscillator, an optical system for converging a parallel laser beam from the laser oscillator to irradiate a workpiece, and a quenching agent near the laser beam spot irradiating the surface of the workpiece. Spraying means for conveying and blowing
A laser processing apparatus comprising: a stage for moving the workpiece. 14. The laser processing apparatus according to claim 13, wherein the laser beam spot and the quenching agent pass through a nozzle having an approximately elliptical and tapered tapered outlet. 15. A laser oscillator, an optical system for converging a parallel laser beam from the laser oscillator to irradiate a workpiece, and a desired gas near a laser beam spot irradiating the surface of the workpiece. A laser processing device comprising: a spraying means for conveying and blowing a quenching agent; and a stage for moving the workpiece. 16. The laser processing apparatus according to claim 15, wherein the laser beam spot, the desired gas, and the quenching agent pass through a nozzle having an approximately elliptical tapered shape. 17. The laser according to claim 13, wherein the optical system converts the cross-sectional shape of the laser beam spot irradiated on the surface of the workpiece into a substantially circular shape, a substantially elliptical shape, or a substantially linear shape. Processing equipment. 18. The laser processing apparatus according to claim 13, wherein the processing of the workpiece is performed in a box provided with a forced exhaust system.