JPH0691388A - Laser beam machine - Google Patents

Abstract

PURPOSE:To eliminate the need for special pre- and post-treatments at the time of executing laser beam processing by using a laser beam which is hardly absorbed. CONSTITUTION:A computer causes an aq. copper sulfate soln. to be discharged to a point P so that the soln. is applied like a spot on this point upon recognition of the positioning of a soln. discharge point 5a at the point P which is the processing start point of a substrate 1. The computer, then, moves an X-Y-Z stage to align an optical axis 18 and the point P and instructs, at the point of this time, a laser oscillator to output the laser beam. The laser beam 23 cast to the point P is absorbed in the aq. copper sulfate soln. to raise the soln. to a high temp. and the substrate 1 in the lower part thereof is made into a molten state. The subsequent laser beam processing is well executed even if the aq. copper sulfate soln. is not applied. Namely, the cutting processing from the point P to the point Q is well executed without the application of the aq. copper sulfate soln. A cutting groove 1a is consequently formed on the substrate 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus for irradiating a processing object with laser light for laser processing, and more particularly to a laser processing apparatus for processing a material such as glass or ceramic which hardly absorbs laser light.

[0002]

2. Description of the Related Art Conventionally, in laser processing of glass, ceramics, etc., a wavelength of 10.6 having good absorption for these materials is used.
Although a carbon dioxide laser of μm has been used, good processing performance cannot be obtained with this carbon dioxide laser due to a large thermal effect due to long wavelength and poor controllability of the laser beam.

This carbon dioxide laser has a wavelength of 1.06
The μm YAG laser is excellent in shortening the pulse and controlling the waveform, and has the advantage of being able to suppress the thermal effect to some extent, but it is difficult to be absorbed by glass and ceramics, and efficient processing is possible. Could not be done. For this reason, a pretreatment such as applying a solvent that easily absorbs laser light (laser light absorbing solution) to the entire surface of the object to be processed or roughening the surface by etching is performed to make it easier for the laser light to be absorbed. (See, for example, JP-A-60-152390). by this,
It becomes possible to melt by laser light on the surface of the workpiece,
The desired laser processing can be performed.

[0004]

However, the above-mentioned conventional method requires pretreatment such as coating, drying, and etching of the laser light absorbing solution on the object to be processed, and post-treatment such as cleaning after processing. It was necessary to add steps. In addition, depending on the object to be processed, it may be difficult to perform processing such as coating, etching, and cleaning, and in such a case, laser processing itself could not be performed.

The present invention has been made in view of the above points, and an object thereof is to provide a laser processing apparatus which does not require a special pre-processing and post-processing for laser processing. Another object of the present invention is to provide a laser processing apparatus capable of performing laser processing on materials, shapes, etc., which have been difficult to perform laser processing in the past.

[0006]

In order to solve the above problems, in the present invention, in a laser processing apparatus for irradiating a laser beam on a processing object to perform laser processing, a laser beam is applied to a processing start point of the processing object. Ejection means for ejecting the absorbing solution,
A laser processing device is provided, which comprises: a laser processing means for performing laser processing by irradiating a laser beam to the processing start point to which the laser light absorbing solution is attached.

[0007]

The discharging means discharges the laser light absorbing solution to the processing start point of the object to be processed, and the laser processing means irradiates the laser beam to the processing start point to which the laser light absorbing solution adheres to perform the laser processing. . Since the laser light absorbing solution is attached to the processing start point, the laser light is absorbed at the processing start point and melting by the laser light starts. Once the melting starts, the laser light absorption rate improves, and even when processing is performed while scanning the laser light, the melting points are sequentially traced. Therefore, even if the laser light absorbing solution does not exist in the processing path, good laser processing proceeds with small energy.

Further, since the laser light absorbing solution is simply attached to the processing starting point, pretreatment such as coating and etching is unnecessary. Furthermore, most of the adhered laser light absorbing solution evaporates at the time of the first laser light irradiation, so that post-treatment such as cleaning is unnecessary. Therefore, laser processing can be easily performed even when a laser beam that is difficult to be absorbed is used. Further, it becomes possible to apply to materials, shapes, assembled workpieces and the like which could not be carried out due to the adverse effects of these pre- and post-treatments.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is an overall configuration diagram of the laser processing apparatus of the present invention. In the figure, a computer 100 is mainly composed of a processor (not shown), and based on a predetermined control program, a laser oscillator 7 and a stage controller 4 are provided.
And outputs a command signal to control the operation of the entire laser processing apparatus.

The laser oscillator 7 is an Nd: YAG laser oscillator and outputs a continuous wave laser beam having a wavelength of 1064 nm in response to a command signal from the computer 100.
The output of the laser light is attenuated by the laser power adjuster 8. The attenuation rate in the laser power adjuster 8 can be controlled by a command from the computer 100. The laser light that has passed through the laser power adjuster 8 is split by the beam splitter 9, and a part of it is power-monitored by the power meter 10. The monitor signal is fed back to the computer 100. The laser light reflected by the beam splitter 9 is introduced into the microscope 11 and the objective lens 12 having a magnification of 50 times, and is focused and irradiated on the surface of the substrate 1.

The substrate 1 is, for example, a glass substrate, and XY
It is fixed to the Z stage 3 via the substrate mounting jig 2.
The substrate 1 can be independently moved in the X, Y, and Z axis directions orthogonal to each other by the stage controller 4 that controls the XYZ stage 3.

A monitor camera 13 provided on the microscope 11.
Captures an image of the laser light irradiation portion of the substrate 1. The imaged data is output to the monitor 15 and displayed as an image, and is also output to the autofocus unit 14. From the imaged data, the autofocus unit 14 detects the distance between the substrate 1 and the objective lens 12 so that the laser beam is always focused on the surface of the substrate 1, and outputs the detected electric signal to the stage controller 4. To do. The stage controller 4 controls the XYZ stage 3 based on the detected electric signal to move the substrate 1 in the Z-axis direction.

A rotary stage 17 is provided at the lower end side of the microscope 11.
A solution ejector 5 is provided via the above. The solution ejector 5 is for ejecting the laser light absorbing solution locally or continuously to the substrate 1, and its ejection amount is controlled by a solution ejection controller 6 which operates in response to a command from the computer 100. It Solution discharge controller 6
The container contains a container for accumulating the laser light absorbing solution, a pump for feeding the laser light absorbing solution, and a valve for adjusting the discharge amount of the laser light absorbing solution. As the laser light absorbing solution, for example, a copper sulfate aqueous solution that highly absorbs Nd: YAG laser light is used. The details of the solution ejector 5 will be described below with reference to FIG.

FIG. 3 is an enlarged view of the solution ejector. As shown in the figure, a linear stage 19 and a piezo element 21 are provided on the outer peripheral portion of the rotary stage 17 on the lower end side of the microscope 11.
The solution ejector 5 is provided on the piezo element 21.
The solution ejector 5 can be rotated about the optical axis 18 of the laser light by 360 ° by the rotary stage 17 having a DC motor 17a and a gear (not shown). Further, the linear movement stage 19 equipped with the DC motor 19a enables the solution ejection port 5a of the solution ejection device 5 to move in the Z-axis direction, and the distance between the optical axis 18 and the solution ejection port 5a can be adjusted by the piezo element 21. Becomes The rotary stage 17, the rectilinear stage 19 and the piezo element 21 are controlled by the stage controller 4 (FIG. 2) which operates in response to a command from the computer 100.

FIG. 1 is an explanatory view of a processing procedure by the laser processing apparatus of the present invention, and (A), (B) and (C) show first, second and third steps, respectively. In the figure,
A case where the substrate 1 is cut from point P to point Q will be described. First, as shown in FIG. 1 (A), the tip of the solution discharge port 5a is attached to the rotary stage 17 (FIG. 3), the linear stage 19 (FIG. 3), the piezo element 21 (FIG. 3) or the XYZ stage 3 (FIG. 2) is moved and controlled so that it is positioned at a point P which is a machining start point. The movement control and the machining operation described later are performed according to a program preset in the computer 100. When the computer 100 recognizes that the solution discharge port 5a is located at the point P, the computer 100 issues a command to the solution discharge controller 6 to apply (adhere) the copper sulfate aqueous solution which is the laser light absorbing solution to the point P, and the copper sulfate is discharged. The aqueous solution is discharged and applied on the substrate 1 in spots. When the processing paths are not continuous, the spotwise application is similarly performed at the starting point of each processing path.

Then, the XYZ stage 3 is moved to
As shown in FIG. 1B, the optical axis 18 and the point P are made to coincide with each other, and at that time, the laser oscillator 7 is instructed to emit the laser light 23.
Is output. The laser beam 23 irradiated to the point P is absorbed by the copper sulfate aqueous solution and becomes high temperature, and the substrate 1 therebelow is brought into a molten state. When the melting starts, the absorption characteristics of the substrate 1 improve, and the melting region becomes a region slightly wider than the laser beam diameter. For this reason, when the irradiation area of the laser beam moves continuously, it follows sequentially where it melts and the absorption characteristics are improved, so in subsequent laser processing, the copper sulfate aqueous solution is not applied. Even if done well. That is, the cutting process from the point P to the point Q in FIG. 1 (C) is satisfactorily performed without applying the copper sulfate aqueous solution, and as a result, the cutting groove 1a is formed in the substrate 1.

As described above, according to this embodiment, it is possible to perform the laser processing without spotting the copper sulfate aqueous solution by spot-wise coating the copper sulfate aqueous solution only at the processing start point. Further, since only the copper sulfate aqueous solution is attached to the processing starting point, the pretreatment such as coating and etching which has been conventionally required is unnecessary. Furthermore, most of the attached copper sulfate aqueous solution evaporates at the time of the first laser light irradiation, so that post-treatment such as cleaning is unnecessary. Therefore, it is possible to easily perform laser processing even on glass, ceramics or the like that hardly absorb the YAG laser. Further, it becomes possible to apply to materials, shapes, assembled workpieces and the like which could not be carried out due to the adverse effects of these pre- and post-treatments.

In the above description, the positioning of the solution discharge port 5a and the application of the copper sulfate aqueous solution are automatically performed, but they may be manually performed. Also,
Although the copper sulfate aqueous solution is used as the laser light absorbing solution that absorbs the Nd: YAG laser light, a graphite aqueous solution or a suspension of carbon, nickel, copper, or the like may be used instead of the copper sulfate aqueous solution. .

Further, the present invention can be similarly applied to the case where the absorption characteristics are further improved in the carbon dioxide laser, and the laser light absorbing solution in that case is, for example, a suspension of titanium carbide powder. A liquid can also be used.

Although the glass substrate is used as the substrate, a ceramic substrate or the like may be used.

[0021]

As described above, according to the present invention, the laser beam absorbing solution is discharged to the processing starting point of the object to be processed, and the laser beam is irradiated to the processing starting point to which the laser beam absorbing solution adheres to perform laser processing. Configured to do. Since the laser light absorbing solution is attached to the processing start point, the laser light is absorbed at the processing start point and melting by the laser light starts. Once the melting starts, the laser light absorption characteristic rate is improved, and even when processing is performed while scanning the laser light, the melting points are sequentially traced. Therefore, even if the laser light absorbing solution does not exist in the processing path, good laser processing can be advanced with small energy.

Further, since the laser light absorbing solution is simply attached to the processing start point, pretreatment such as coating and etching is unnecessary. Furthermore, most of the adhered laser light absorbing solution evaporates at the time of the first laser light irradiation, so that post-treatment such as cleaning is unnecessary. Therefore, laser processing can be easily performed even when a laser beam that is difficult to be absorbed is used. Further, it becomes possible to apply to materials, shapes, assembled workpieces and the like which could not be carried out due to the adverse effects of these pre- and post-treatments.

[Brief description of drawings]

FIG. 1 is an explanatory view of a processing procedure by a laser processing apparatus of the present invention.

FIG. 2 is an overall configuration diagram of a laser processing apparatus of the present invention.

FIG. 3 is an enlarged view of a solution ejector.

[Explanation of symbols]

 1 Substrate 3 XYZ Stage 4 Stage Controller 5 Solution Discharger 6 Solution Discharge Controller 7 Laser Oscillator 13 Monitor Camera 14 Auto Focus Unit 17 Rotating Stage 19 Straight Stage 21 Piezo Element 100 Computer

Claims (2)

[Claims] 1. A laser processing apparatus for irradiating a processing object with laser light to perform laser processing, comprising: a discharging unit configured to discharge a laser light absorbing solution to a processing start point of the processing object; and the laser light absorbing solution. A laser processing device, comprising: laser processing means for performing laser processing by irradiating the attached processing start point with laser light. 2. The laser processing apparatus according to claim 1, wherein the object to be processed is made of glass or ceramics.