JPH0919787A - Working method of non-metallic material and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an edge part of a cut surface smooth and uniform without generating cracks, to prevent fine powders of a non-metallic material generated during cutting from sticking and to correctly work into a desired pattern in the case of working the non-metallic material. SOLUTION: In a working method wherein the non-metallic material 10 is worked with the non-metallic material 10 transfered while allowing an assist gas 12 to flow along the propagating direction of a CO2 laser beam 11 and irradiating on the surface of the non-metallic material 10 with the CO2 laser beam 11, the surface of the non-metallic material 10 is worked while getting it wet with a water 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention irradiates a surface of a non-metallic material with carbon dioxide laser light while flowing an assist gas along the direction of propagation of carbon dioxide laser light, and moves the non-metal material to remove the non-metal material. The present invention relates to a method of processing a non-metallic material to be processed and a processing apparatus therefor.

[0002]

2. Description of the Related Art In recent years, on and in substrates of non-metal materials such as glass materials, magnetic materials, semiconductor materials and dielectric materials,
Product development of integrated circuits, optical integrated circuits having optical circuits mounted therein, or electric / optical integrated circuits in which electric circuits and optical circuits are integrated has become active.

This type of integrated circuit is densely integrated in a range of several tens to several tens of thousands on a circular or square substrate having a size of 3 inches to 10 and several inches. For example, as shown in FIG. 5, the substrate 701 is cut and separated into n × m integrated circuit 702 chips. As a method of cutting and separating the substrate 701, the substrate 701 is defined by alternate long and short dash lines 703a to 703.
n, 704a to 704m, diamond blade dicing is performed or scribing is performed by irradiating a laser beam.

FIG. 6 is a schematic view of an apparatus to which the method of processing a substrate material proposed by the present inventor has been applied (Japanese Patent Application No. 6-
247436).

[0005] This is on the base 803 while blowing the assist gas G through the assist gas introduction pipe 802 around the laser light L which is emitted from the carbon dioxide gas (CO ₂ ) laser 801 and then condensed by the condenser lens Le. The glass substrate 804 fixed by vacuum suction is irradiated and cut into two pieces A and B. Reference numeral 805 is a through hole.

[0006]

By the way, it has been found that the following problems occur when a non-metallic material substrate having a large coefficient of thermal expansion is cut or a slit is formed using the apparatus shown in FIG. .

(1) When a non-alkali glass substrate (thickness: 1.1 mm) for a liquid crystal display is cut, innumerable micro cracks 2-1 due to thermal deformation strain are formed on the edges of the cut substrates 1-1, 1-2. 2-2 occurs and breaks, resulting in cutting at a cutting margin width Wr (1 mm or more) much wider than a desired cutting margin width Wd (100 μm or less).

(2) Uneven irregularities are also generated on both side surfaces of the cut substrates 1-1 and 1-2 and both edge portions 3-1 and 3-2 (when cutting is completed (FIG. 7A)). After cutting for several tens of seconds (Fig. 7
(B))).

(3) Fine powder of non-metallic material generated during cutting adheres to the cut surface and the front and back surfaces of the substrate.

(4) The non-alkali glass substrate for liquid crystal display may be satisfactorily cut, but the yield is very low, and if left for a while after the cutting, cracks occur at the edge of the cut substrate, As a result, it cracks unevenly.

(5) Since it is not easy to accurately control the moving direction and the position of the beam spot of the carbon dioxide laser beam applied to the non-metallic material, it is difficult to control the linear shape or the curved shape, or the combination of the straight line and the curved line. It is not easy to accurately process the desired pattern.

[0012]

In order to achieve the above object, the present invention is directed to irradiating a surface of a non-metallic material with carbon dioxide laser light while flowing an assist gas along the direction of propagation of carbon dioxide laser light, In a method of processing a non-metal material, which moves a material to process a non-metal material, the surface of the non-metal material is processed while being wet with water.

In addition to the above configuration, the present invention is one in which the assist gas is sprayed in a concentrated manner on the spot surface on the substrate irradiated with the laser beam.

In addition to the above configuration, the present invention is one in which water is sprayed toward a spot surface irradiated with laser light.

In addition to the above structure, the present invention uses a carbon dioxide gas laser beam having a wavelength of 9.0 μm to 1 depending on the type of non-metallic material.
A single wavelength laser beam selected using a grating from the range of up to 1.3 μm may be used.

The present invention also provides a carbon dioxide gas laser device,
An optical system for guiding and condensing laser light emitted from a carbon dioxide laser device to a non-metallic material for processing, a gas introduction system for flowing an assist gas along the propagation direction of the laser light, and a non-metallic material A stage for holding, a moving device for moving the stage in a direction perpendicular to the propagation direction of the laser light, a mechanism for vacuum-adsorbing the non-metallic material on the stage, and for wetting the surface of the non-metallic material with water. And a water introduction system.

In addition to the above-mentioned structure, the present invention includes a monitor device for previously monitoring a cut portion of a substrate with a CCD camera, and an image processing device for image-processing a monitor signal from the monitor device.
A control device that controls the movement of the moving device by a signal from the image processing device may be provided.

According to the above structure, a carbon dioxide laser beam is irradiated onto a very small area on the surface of the non-metal material made of a non-metal material wetted with water, and an assist gas is blown to the carbon dioxide laser of the non-metal material. An extremely small area exposed by the beam spot of light is exposed. For this reason, the surface of the non-metallic material is directly irradiated with the beam spot, and the light energy of the carbon dioxide laser light is absorbed by the water in the area wetted by the water. Therefore, the light energy (thermal stress) is applied only to the extremely small area of the non-metallic material.
Are concentrated, the non-metallic material is cut or cleaved without the occurrence of cracks, and the edges of the cut surface are smooth and uniform. Further, since the surface of the non-metal material is wet with water, the fine powder of the non-metal material generated during cutting floats in the water and is unlikely to adhere to the non-metal material.

When the water is sprayed toward the spot surface irradiated with the laser beam, the fine powder of the non-metal material generated at the time of cutting is forcibly washed out and does not adhere.

When the carbon dioxide gas laser beam is a single wavelength laser beam selected by using a grating from the wavelength range of 9.0 μm to 11.3 μm depending on the type of non-metallic material, it is smoother. A uniform machined surface is formed.

[0021] The cutting point of the non-metallic material is C in advance in the processing device.
When a monitor device for monitoring with a CD camera, an image processing device for image-processing a monitor signal from the monitor device, and a control device for controlling the movement of the moving device by a signal from the image processing device are provided, a non-metal Since the moving direction and the position of the spot of the laser beam on the material can be accurately controlled, it is processed into a desired pattern.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION When the present invention is applied to the processing of a non-metallic material, carbon dioxide laser light is applied to an extremely small area on the surface of the non-metallic material which is wetted with water. An assist gas is sprayed so that a very small area portion irradiated with a beam spot of a carbon dioxide gas laser beam of a non-metal material is exposed. The surface of the non-metallic material is directly irradiated with the beam spot, and the light energy of the carbon dioxide laser light is absorbed by the water in the surrounding area wet with water. For this reason, light energy (thermal stress) is concentrated only on the extremely small area of the non-metallic material, so that the non-metallic material is cut or cleaved without causing cracks, and the edge of the cut surface is smooth and uniform. Become. Since the surface of the non-metallic material is wet with water, the fine powder of the non-metallic material generated during cutting floats in the water and is prevented from adhering to the non-metallic material.

As the non-metal material, brittle materials such as glass and ceramics are suitable. As assist gas,
O ₂ , Ar, N ₂ , air or a mixed gas thereof is used.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a diagram showing the principle of the method for processing a non-metallic material according to the present invention.

As shown in the figure, the surface of the substrate 10 made of a non-metallic material is irradiated with carbon dioxide (CO ₂ ) laser light (hereinafter referred to as “laser beam”) 11 and the propagation direction of the laser beam 11 (arrow). 11-1), an assist gas (N ₂ , O ₂ , Ar or air) 12 is blown along the surface of the substrate 10 to evaporate a very small area portion (hereinafter referred to as “spot surface”) of the beam spot of the substrate 10. Is a method of wetting the surface of the substrate 10 with water when cutting (or cleaving by generating cracks 13 due to thermal stress).

The substrate 10 is cut or cleaved by moving a substrate fixing XY stage (hereinafter referred to as "stage") 15 in the X and Y directions.

The stage 15 is formed in accordance with the size of the substrate 10 and has a substantially concave cross section. Recess 15
A concave portion 15-2 is further formed at the center of -1.
A ZnSe light-transmitting plate 16 is fitted in the recess 15-2. A laser beam through hole 1 is provided at the center of the recess 15-2.
5-3 is formed. The substrate 10 is placed on the concave portion 15-1 of the stage 15 and is closely fixed on the stage 15 by the vacuum suction device 17. The substrate 10 is made of glass,
Brittle materials such as ceramics are suitable. A water film 14 is formed on the surface of the substrate 10. In addition, 18 is a gas nozzle.

Since the assist gas 12 is blown into the gas nozzle 18 along the propagation direction of the laser beam 11, the water film 14 is partially blown by the blow of the assist gas near the spot surface of the substrate 10 irradiated with the laser beam 11. Are removed to expose the substrate 10. Therefore, the laser beam 11 is directly irradiated on the inside of the spot surface on the substrate 10, so that the light energy density becomes high (the light energy distribution becomes narrow and steep).

On the other hand, the outside of the spot surface on the substrate 10 is covered with the water film 14, and the carbon dioxide laser light that is easily absorbed by water is emitted, so that the light energy density becomes small on the outside of the spot surface. The transfer of heat to the substrate 10 due to light energy is suppressed. That is, the light energy is concentrated only on the spot surface of the substrate 10. Therefore, generation of microcracks in the substrate 10 due to thermal strain is suppressed, and the cutting margin is reduced. Further, in the case of cleaving, the progress of cracks due to thermal stress can be promoted by wetting with water, and cleaving is faithfully performed along the locus irradiated with laser light. Further, since the fine powder of the substrate 10 generated during the processing floats inside the water film 14, it does not adhere to the non-metallic material.

In the above, the surface of the substrate is wetted with water, and when the laser beam is irradiated onto the substrate, the assist gas is caused to flow to the outer periphery of the spot, so that the spot irradiated with the laser beam on the substrate. Light energy is concentrated only on the surface, and the generation of microcracks due to the heat distribution around the spot is suppressed. Further, the width of cutting margin is narrowed and a uniform cut surface can be obtained.

FIG. 2 is a diagram showing an embodiment of a processing apparatus to which the method for processing a non-metallic material of the present invention is applied.

In the figure, reference numeral 20 is a carbon dioxide laser device, and an external grating portion 2 is provided in a box 21.
2 and a carbon dioxide laser tube 23 are provided. An internal mirror 24 and a Brewster window 25 are provided at both ends of the carbon dioxide laser tube 23, respectively. Carbon dioxide laser tube 2
3 is a mixed gas (CO ₂ , N ₂ and He at a mixing ratio of 8: 1).
Gas mixed in a ratio of 8:74) 26 is enclosed. A pair of electrodes 2 is provided near the end of the carbon dioxide laser tube 23.
7-1, 27-2 are provided, and both electrodes 27-1,
27-2 are connected to the drive power supply 28, respectively.

A monitor light detecting mirror 29, which is a half mirror for taking out a part L2 of the emitted laser light L1, is provided at the emission opening (on the side of the internal mirror 24) of the carbon dioxide laser device 20. The laser light L2 reflected by the monitor light detecting mirror 29 is monitored by a monitor light detector 30 and is taken out as a monitor signal 31. A feedback signal 32 based on the monitor signal 31 is fed back to the drive power source 28, and the laser light L
The output of 1 is kept constant.

The laser light L3 transmitted through the monitor light detecting mirror 29 is reflected by the total reflection mirror 34 to the side of the substrate 35 to be processed (lower side in the figure) via the optical shutter opening / closing adjusting section 33. The laser light L3 reflected by the total reflection mirror 34 is condensed by the condenser lens 36 to be a laser beam.

These total reflection mirror 34 and condenser lens 36
An optical system 37 is formed by the optical system 37, and the optical system 37 includes a monitor light detection mirror 29, an optical shutter 38 of the optical shutter opening / closing adjuster 33, and a casing 39 formed of a tubular body having an L-shaped cross section.
Housed within.

A gas introduction system 42 including a gas supply port 40 and a gas nozzle 41 for blowing the assist gas G1 along the propagation direction of the laser beam L3 is provided at the laser beam emission port of the housing 39 of the optical system 37. ing. Gas introduction system 4
A substrate holding / moving device 43 is arranged below 2.

The substrate holding and moving device 43 comprises a stage 44 for holding the substrate and a moving device 45 for moving the stage 44 in at least the X and Y directions. The stage 44 is provided with a vacuum suction device 46 for vacuum-adsorbing the substrate 35 on the stage 44, and a water introduction system (not shown) for forming a water film 47 on the surface of the substrate 35.
Is provided. Incidentally, 48 is a ZnSe transparent plate,
49 is a laser beam through hole.

In such a processing apparatus, when the substrate 35 is cut by evaporation, the value of (f + g) is set to the focal length value of the condenser lens 36. When the substrate 35 is broken by cutting, the value of (f + g) is equal to that of the condenser lens 35.
A value obtained by adding 5 to 12 mm to the focal length of is preferable. The oscillation wavelength of the laser light output from the carbon dioxide gas laser device 20 is 9.0 μm by adjusting the angle θ by rotating the angle adjusting unit 22-1 of the grating unit 22 in the arrow direction 22-2. A single oscillation wavelength is selected from the range of 11.3 μm. The selection of this wavelength can be changed depending on the type of the substrate 35. For example, in the case of a glass or ceramic substrate, the wavelength is about 10.
6 μm is preferable, but about 9.1 μm in case of Si substrate
Is preferred.

Specific examples of processing a non-metallic material using such a processing apparatus will be shown below using numerical values, but the numerical values are not limited.

(Specific Example 1) A substrate 35 made of non-alkali glass having a thickness of 1.1 mm is irradiated with a laser beam having an output of 70 W from the carbon dioxide laser device 20, and the substrate 35 is moved in the X direction at a speed of 10 mm / sec. Let A water film 47 having a thickness of about 1 mm was formed on the substrate 35. Assist gas G
N ₂ gas was used as the gas, and the pressure at the outlet of the gas nozzle 41 was set to 3 Kg / cm ² . Further, the laser beam was focused and focused on the surface of the substrate 35 to perform cutting. As a result, it was possible to perform cutting processing with a cutting margin width of 100 μm or less and without microcracks. On the other hand, when the water film 47 on the substrate 35 is removed and the same cutting process is performed, microcracks are generated on the cut surface of the substrate 35, and the microcracks cause cracks in the glass near the cut surface. The cut surface was deformed into a non-uniform shape.

(Specific Example 2) Under the conditions of Specific Example 1, the focal position of the laser beam is set to be located 9 mm above the upper surface of the substrate 35, and the substrate 35 is set to 12 mm / in the X direction.
The substrate 35 could be cut by moving at a speed of sec. In this case as well, in order to compare with the conventional method,
The water film 47 on the substrate 35 was removed and the same cleaving process was performed. However, cracks due to thermal stress did not occur on the surface of the substrate 35, and the substrate 35 was not cleaved. Then, it was found that when the moving speed of the substrate 35 was slowed down to 7 mm, the fracturing was performed for a while, but microcracks were generated on the fracturing surface.

(Specific Example 3) In the specific example 2, the substrate 35 is used.
Instead of non-alkali glass substrate, the thickness is 1.5
mm alumina substrate, substrate 35 in the X direction 5 mm
When the fracturing process was performed while changing the cutting speed in the range of 10 sec / sec to 10 mm / sec, a uniform fracture surface without microcracks could be obtained. The cutting process could be performed even with the water film 47 removed, but the moving speed in the X direction was 3
The range was from mm / sec to 7 mm / sec. That is, it was found that by forming the water film 47 on the substrate 35, the crack progresses at a higher speed.

FIG. 3 is a view showing the concept of another embodiment of the method for processing a non-metal material according to the present invention.

This is a method in which water 52 is cut or cleaved while spraying water 52 in the direction of arrow 52-1 on the surface of the substrate 51 irradiated with the laser beam 50. The substrate 51 moves in a direction (arrow 51-1 direction) substantially equal to the water spraying direction. In the figure, 53 is a gas nozzle and 54 is an assist gas.

While the substrate 51 is being irradiated with the laser beam while the assist gas 54 is flowing along the propagation direction of the laser beam 50, the substrate 51 is moved and the water 5
According to the method in which 2 is blown to cut or cleave the substrate 51, dust attached to the cut or cleaved surface or the surface of the substrate 51 and fine particles of the substrate 51 are forcibly washed away.
The direction of spraying the water 52 is opposite to the direction shown in FIG.
That is, it may be opposite to the moving direction 51-1 of the substrate 51.

FIG. 4 is a diagram showing another embodiment of a processing apparatus to which the method for processing a non-metallic material of the present invention is applied. The same reference numerals are used for the same members as those in the embodiment shown in FIG.

The difference from the processing device shown in FIG. 2 is that it has a monitor device, an image processing device, and a control device.

This processing device is a CC as a monitor device.
The D camera 60 monitors the portion to be cut or cleaved in advance, and the monitor signal from the CCD camera 60 is sent to the image processing device 61.
The image is processed by inputting the image data to the input device, the computer 62 as a control device is operated based on the image processing signal, and the optical shutter drive circuit 63 and the XYZ stage controller 64 are operated.

With such a command system, it is possible to accurately process a desired portion of the substrate 35 into a straight line or a curved line, or a pattern in which a straight line and a curved line are combined.

In the present embodiment, the case of processing a glass substrate has been described, but the present invention is not limited to this, and Ga may be processed.
A semiconductor substrate such as As or InP, a substrate made of a magnetic material, a ferroelectric material, a polymer material or the like may be processed.

In this embodiment, the laser light is guided and condensed by the total reflection mirror and the condenser lens, but the invention is not limited to this, and the concave mirror may guide and condense the laser light.
Furthermore, in the processing method shown in FIG. 1 and the processing method shown in FIG.
The Se translucent plate may be replaced with one that reflects laser light like a metal plate or one that absorbs laser light like an insulating plate (in the case of cleaving, the laser light reaching the back surface of the substrate is weak). This is because). In this case, the laser beam through hole may be omitted.

[0053]

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

(1) Since carbon dioxide laser light is radiated while the surface of the non-metallic material is wet with water, cracks do not occur, the edges of the cut surface are smooth and uniform, and No adhesion of fine powder of metallic material.

(2) By providing the processing device with the monitor device, the image processing device, and the control device, the non-metallic material can be accurately processed into a desired pattern.

[Brief description of the drawings]

FIG. 1 is a principle diagram of a method for processing a non-metallic material according to the present invention.

FIG. 2 is a diagram showing an embodiment of a processing apparatus to which the method for processing a non-metallic material of the present invention is applied.

FIG. 3 is a view showing a conceptual diagram of another embodiment of the method for processing a non-metallic material of the present invention.

FIG. 4 is a diagram showing another embodiment of a processing apparatus to which the method for processing a non-metallic material of the present invention is applied.

FIG. 5 is a plan view of a substrate for explaining a method of cutting and separating an integrated circuit.

FIG. 6 is a schematic diagram of a method of processing a substrate material and an apparatus thereof, which the present inventor has previously proposed.

FIG. 7A is a plan view of the non-metallic material immediately after cutting by the processing device previously proposed by the present inventor, and FIG. 7B is a plan view of the non-metallic material several tens of seconds after the cutting. Is.

[Explanation of symbols]

 10 Non-Metallic Material (Substrate) 11 Carbon Dioxide Laser Light (Laser Beam) 12 Assist Gas 14 Water (Water Film)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B23K 26/18 B23K 26/18

Claims (6)

[Claims] 1. A non-metallic material is processed by moving the non-metallic material while irradiating the surface of the non-metallic material with the carbon dioxide laser light while flowing an assist gas along the propagation direction of the carbon dioxide laser light. A method of processing a non-metallic material, which comprises processing the surface of the non-metallic material while wetting it with water. 2. The method for processing a non-metal material according to claim 1, wherein the assist gas is sprayed in a concentrated manner onto a spot surface on the non-metal material irradiated with laser light. 3. The method for processing a non-metallic material according to claim 1, wherein the water is sprayed toward a spot surface irradiated with laser light. 4. The carbon dioxide laser light is a single wavelength laser light selected using a grating from a wavelength range of 9.0 μm to 11.3 μm according to the type of non-metallic material. 4. The method for processing a non-metallic material according to any one of 1 to 3. 5. A carbon dioxide gas laser device, an optical system for guiding and condensing laser light emitted from the carbon dioxide gas laser device to a non-metallic material for processing, and an assist gas along a propagation direction of the laser light. A gas introduction system for flowing,
A stage for holding the non-metallic material, a moving device for moving the stage in a direction perpendicular to the propagation direction of the laser light, a mechanism for vacuum-adsorbing the non-metallic material on the stage, the non-metallic material And a water introduction system for wetting the surface of the surface with water. 6. The cut portion of the non-metal material is CCD in advance.
The monitor device for monitoring with a camera, an image processing device for image-processing a monitor signal from the monitor device, and a control device for controlling the movement of the moving device by a signal from the image processing device. Equipment for processing non-metallic materials.