JP3052931B2 - Laser processing apparatus and processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser drilling machine for printed circuit boards.

[0002]

2. Description of the Related Art A conventional technique will be described below. FIG. 6 shows an example of a conventional laser drilling machine. FIG.
In the figure, 101 is a laser oscillator, 102 is a collimator, 103 is a mask, 104 is a transfer lens, and 105 is a workpiece, for example, a resin substrate containing glass fiber.

Next, the operation of the conventional technique will be described. The laser beam output from the laser oscillator 101 is enlarged and reduced in beam diameter by a collimator 102 and a mask 103
Is irradiated. The irradiated laser light is partially shielded by the mask 103, and the laser light passes only through the central hole,
An image is formed on the workpiece 105 by the transfer lens 104. Therefore, the shape of the mask 103 is imaged and processed on the workpiece 105.

[0004]

However, in the above-mentioned conventional configuration, a short pulse (about 1 μS) of laser light is used in order to reduce the energy applied to the mask in order to prevent burning of the mask. When the material or the mask diameter changes, the glass fiber remains due to the difference in the energy transmittance or the processing threshold value, the processing bottom surface is damaged, and the processing quality cannot be maintained. Was.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a stable processing quality when laser drilling various kinds of substrate materials using masks having various diameters. I do.

[0006]

In order to achieve the above object, a first means of the present invention is to provide a laser emitting a laser beam.
Processed by the vibrator, the laser oscillator and the laser beam
A mask disposed between the workpieces;
Transfer lens and laser disposed between workpieces
Two or more collimators are provided between the oscillator and the mask.
And at least one of the lenses constituting the collimator
One lens is fixedly placed on the laser beam, and the remaining
Move the lens over the laser beam and collimate
A moving means for moving the whole data in the optical axis direction is provided.

A second means is a laser for outputting a laser beam.
An oscillator, processed by the laser oscillator and the laser light.
A mask disposed between the workpieces,
A transfer lens disposed between the workpieces and the laser beam;
Two or more collimators between the oscillator and the mask
One is configured to emit laser light, and the other is
A collimator configured to converge light is arranged, and
When one of the collimators is moved over the laser beam
In addition, movement for moving the entire collimator in the optical axis direction
Means are provided.

The third means is a laser for outputting a laser beam.
An oscillator, processed by the laser oscillator and the laser light.
A mask disposed between the workpieces,
A transfer lens disposed between the workpieces and the laser beam;
Two or more collimators between the oscillator and the mask
And at least one of the lenses constituting the collimator
One lens is fixedly placed on the laser beam, and the remaining
Move the lens over the laser beam and collimate
Moving means for moving the whole data in the optical axis direction, at least
A control means for controlling the moving means is provided.

A fourth means is a laser for outputting a laser beam.
An oscillator, processed by the laser oscillator and the laser light.
A mask disposed between the workpieces,
A transfer lens disposed between the workpieces and the laser beam;
Two or more collimators between the oscillator and the mask
One is configured to emit laser light, and the other is
A collimator configured to converge light is arranged, and
Moving one of the collimator on the prior SL laser beam DOO
In addition, movement for moving the entire collimator in the optical axis direction
Means and control means for controlling at least the moving means .

The fifth means is a laser for outputting a laser beam.
An oscillator, processed by the laser oscillator and the laser light.
A mask disposed between the workpieces,
A transfer lens disposed between the workpieces and the laser beam;
Two or more collimators between the oscillator and the mask
One is configured to emit laser light, and the other is
A collimator configured to converge light is arranged, and
When one of the collimators is moved over the laser beam
In particular, when the entire collimator is moved in the optical axis direction,
In addition, movement for moving the entire collimator in the optical axis direction
Means and control means for controlling at least the moving means .

Sixth means is a laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, and a mask disposed between the mask and the workpiece. By using a laser processing apparatus provided with two or more collimators between the transfer lens and the laser oscillator and the mask disposed, a small number of the collimators are used.
Move at least one over the laser beam and
It has a step of moving the entire remeter in the optical axis direction .

A seventh means is a laser for outputting a laser beam.
An oscillator, processed by the laser oscillator and the laser light.
A mask disposed between the workpieces,
A transfer lens disposed between the workpieces and the laser beam;
Two or more collimators between the oscillator and the mask
Laser light diverges on one side using the laser processing equipment
And the other is configured to converge the laser beam.
A meter and place one of the collimators in the
While moving on the ray, the entire collimator
While moving in the optical axis direction, the entire collimator
It has a step of moving in the optical axis direction .

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the above configuration, the two or more
A moving means for moving at least one of the collimators on the laser beam and moving the entire collimator in the optical axis direction is provided so that the beam diameter irradiated on the mask can be adjusted, and the brightness and the intensity of the beam passing through the mask can be adjusted. The energy can be controlled, and the processing quality such as the shape and shape of the inner wall of the processing hole due to the change of the material or the mask diameter can be stabilized.

Further , as in the prior art, a gas laser is provided with 1 μS.
Laser pulse waveform is unstable when near short pulse output
However, using the present invention, the laser pulse is relatively stable
For example, while maintaining the waveform around 10 μS
Control of the energy passing through the
Energy can be stabilized, and stable processing quality
Can be obtained.

In the above configuration, one side emits a laser beam.
And the other is configured to converge the laser beam.
Place a remeter and connect one of the collimators to the
And collimator as a whole
A moving means for moving the light in the optical axis direction is provided, and the mask is irradiated.
Beam diameter is adjustable, and the beam passing through the mask is adjusted.
Control the brightness and energy of the
The shape and shape of the inner wall of the machined hole due to the change and the change of the mask diameter
Processing quality such as shape can be stabilized.

Further , as in the conventional case, the gas laser is provided with 1 μS.
Laser pulse waveform is unstable when near short pulse output
However, using the present invention, the laser pulse is relatively stable
For example, while maintaining the waveform around 10 μS
Control of the energy passing through the
Energy can be stabilized, and stable processing quality
Can be obtained.

Reference Example 1 Hereinafter, a reference example relating to the present invention will be described with reference to the drawings. FIG. 1 shows a reference example of a laser processing apparatus and a processing method. In FIG. 1A, 1 is a laser oscillator, 2 and 3 are lenses constituting a collimator,
In the case of this example, a Kepler-type collimator is configured, 2 is a fixed lens, and 3 is a movable lens. Reference numeral 4 denotes a mask, 5 denotes a transfer lens, 6 denotes a workpiece, 7 denotes a driving device for the movable lens 3, and 8 denotes a driver. FIG. 1B shows the state of laser light when the distance between the fixed lens 2 and the movable lens 3 is reduced, as an example of moving the movable lens 3.

Hereinafter, the operation of the reference example will be described. In this figure, a Kepler-type collimator is configured, and a fixed lens 2
It is possible to control the diameter of the beam irradiated on the mask 4 by changing the distance between the lens 4 and the movable lens 3.

As shown in FIG. 1B, the fixed lens 2
When the movable lens 3 is moved closer to the beam, the beam tends to spread to the diverging side. Conversely, when the beam is moved farther away, a beam that tends to converge is obtained, and the beam diameter applied to the mask 4 can be controlled. Since the diameter of the mask 4 is determined by the diameter required for processing, a beam diameter suitable for the mask diameter can be obtained.

FIG. 2 shows the luminance distribution of a single mode laser beam. As is clear from FIG. 2, the beam has a distribution in which the luminance is high at the center and the luminance decreases toward the periphery. Therefore, when the mask is irradiated with a laser beam having a beam diameter appropriate for the mask diameter, it is possible to control the brightness of the laser beam passing therethrough and the energy passing through the mask, and as a result, the shape and shape of the hole wall surface processed For example, a difference in processing quality due to a change in mask diameter or material can be reduced, and stable processing quality can be ensured.

The driving device 7 can save power by controlling the position of the movable lens 3 in accordance with the driver 8 instructed by the controller. Reference Example 2 FIG. 3 shows a second reference example of the present invention .

In FIG. 3A, reference numeral 11 denotes a laser oscillator, 12, 13, and 14 denote lenses constituting a collimator. Two sets of Kepler type collimators in this embodiment are formed, and 12 is a fixed lens. Reference numerals 14 and 14 denote first and second movable lenses, respectively. The laser is incident on the second movable lens and irradiates the mask while converging. Reference numeral 15 denotes a mask, 16 denotes a transfer lens, 17 denotes a workpiece, 18 denotes a driving device for the movable lenses 13 and 14, and 19 denotes a driver.

FIG. 3B shows an example of moving the movable lenses 13 and 14 when the laser beam enters the first movable lens 13 and irradiates the mask while diverging. showed that.

The operation of this embodiment will now be described with reference to the drawings, taking a Kepler-type collimator as an example. The distance between the fixed lens 12 and the first movable lens 13 and the second movable lens 14 is different so that when a laser beam is incident on the first movable lens 13 shown in FIG. Then, the mask 15 is irradiated. On the other hand,
When a laser beam is incident on the second movable lens 14 shown in FIG. 3A, the laser beam is adjusted to a convergent beam and is irradiated on the mask 15.

By switching between the two sets of collimators adjusted to different characteristics as described above, it is possible to control the diameter of the beam irradiated on the mask 4. As is clear from FIG. 2, the beam has a distribution in which the luminance is high at the center and the luminance decreases toward the periphery. Therefore, when the mask is irradiated with a laser beam having a beam diameter appropriate for the mask diameter, it is possible to control the brightness of the laser beam passing therethrough and the energy passing through the mask, and as a result, the shape and shape of the hole wall surface processed For example, a difference in processing quality due to a change in mask diameter or material can be reduced, and stable processing quality can be ensured. In particular, in the case of a gas laser, the laser pulse waveform becomes unstable at the time of outputting a short pulse around 1 μS. Since the energy to be processed can be controlled, the energy reaching the processing point can be stabilized, and a stable processing quality can be obtained.

Further, the driving device 7 can save power by controlling the position of the movable lens 3 in accordance with the driver 8 instructed by the controller. Embodiment FIG. 4 shows an embodiment of the present invention .

In FIG. 4A, 21 is a laser oscillator, 22 and 23 are lenses forming a first collimator,
Reference numerals 24 and 25 denote lenses constituting a second collimator. In the case of this example, two sets of Galileo collimators are configured. In this figure, a laser beam is incident on a Galileo collimator composed of 24 and 25 lenses, and irradiates the mask while diverging. 26 is a mask, 27 is a galvano scanner that scans a laser beam at a predetermined location, 28 is an f-Θ lens having a transfer lens function, 29 is a workpiece, 30 is a driving device for switching between the two sets of collimators, 31 Is a driving device that moves the collimator in the optical axis direction,
32 is a driver.

FIG. 4B shows the state of the laser beam when the laser beam enters the first movable lens 13 and irradiates the mask while converging, as an example of moving two sets of collimators. Indicated.

The operation of this embodiment will now be described with reference to the drawings, taking a Galileo collimator as an example. The collimators are arranged so that the distance between the first collimator including the lenses 22 and 23 and the second collimator including the lenses 24 and 25 are different from each other. In the example shown in FIG. 4B, when a laser beam is incident on the first collimator, the laser beam is adjusted to a convergent beam and irradiated on the mask 26.

On the other hand, in the example shown in FIG. 4A, when a laser beam is incident on the second collimator, the laser beam is adjusted to a divergent beam and is irradiated on the mask 26. The diameter of the beam applied to the mask 26 is controlled by switching between the two sets of collimators adjusted to different characteristics as described above and further moving each collimator in the optical axis direction by the driving device 31 that moves in the optical axis direction. It is possible.

As is clear from FIG. 2, the beam has a distribution in which the brightness is high at the center and the brightness decreases toward the periphery. Therefore, when the mask is irradiated with a laser beam having an appropriate beam diameter with respect to the mask diameter, it is possible to control the brightness of the laser beam passing therethrough and the energy passing through the mask, and as a result, the shape and shape of the processed hole wall surface A difference in processing quality due to a change in mask diameter or material can be reduced, and stable processing quality can be secured.

In particular, in the case of a gas laser, the laser pulse waveform becomes unstable at the time of outputting a short pulse near 1 μS. However, according to the present invention, the laser pulse is relatively stable, for example, while maintaining a waveform near 10 μS. Since the energy passing through the mask can be controlled, the energy reaching the processing point can be stabilized, and stable processing quality can be obtained.

Further, a driving device 30 for switching between two sets of collimators and a driving device 31 for moving each collimator in the optical axis direction control the position of each collimator with respect to the mask 26 according to a driver 32 commanded by a controller. Can save labor.

[0034] The (Reference Example 3) Figure 5 shows a third reference example of the present invention. FIG.
4A, reference numeral 41 denotes a laser oscillator, reference numeral 42 denotes a fixed lens, reference numeral 43 denotes a first movable lens, reference numeral 44 denotes a second movable lens. In this example, two sets of Kepler-type collimators are configured. In this figure, a laser beam is incident on a Kepler-type collimator composed of 42 and 44 lenses, and irradiates the mask while diverging. 45 is a mask, 46 is a transfer lens, 47 is a workpiece, 48 is a driving device for switching the movable lens, 49 is a driving device for moving the movable lenses 43 and 44 in the optical axis direction, and 50 is a driver.
FIG. 5B shows the state of the laser beam when the laser beam enters the first movable lens 43 and irradiates the mask while converging, as an example of moving the movable lens.

Next, the operation of this embodiment will be described with reference to the drawings, taking a Kepler-type collimator as an example. First composed of a fixed lens 42 and a lens movable lens 43
The collimators are arranged such that the distance between the lenses differs between the second collimator including the collimator, the fixed lens 42, and the movable lens 44. In the example shown in FIG. 5B, when a laser beam is incident on the first collimator, the laser beam is adjusted to a convergent beam and irradiated on the mask 45. On the other hand, FIG.
In the example shown in (a), when a laser beam is incident on the second collimator, the beam is adjusted to a divergent beam and is irradiated on the mask 45.

By switching between the two sets of collimators adjusted to different characteristics as described above, and further moving each collimator in the optical axis direction by the driving device 49 for moving in the optical axis direction, the beam diameter to be irradiated on the mask 45 is obtained. Can be controlled.

As is clear from FIG. 2, the beam has a distribution in which the luminance is high at the center and the luminance decreases toward the periphery. Therefore, when the mask is irradiated with a laser beam having an appropriate beam diameter with respect to the mask diameter, it is possible to control the brightness of the laser beam passing therethrough and the energy passing through the mask, and as a result, the shape and shape of the processed hole wall surface A difference in processing quality due to a change in mask diameter or material can be reduced, and stable processing quality can be secured.

In particular, in the case of a gas laser, the laser pulse waveform becomes unstable at the time of outputting a short pulse of about 1 μS. However, when the present invention is used, the laser pulse maintains a relatively stable waveform of, for example, about 10 μS while maintaining the waveform. Since the energy passing through the mask can be controlled, the energy reaching the processing point can be stabilized, and stable processing quality can be obtained.

Further, a driving device 48 for switching between two sets of collimators and a driving device 49 for moving each collimator in the optical axis direction control the position of each collimator with respect to the mask 26 according to a driver 50 commanded by a controller. Can save labor.

As described above, by providing a mechanism for switching the collimator or moving the position of the lens constituting the collimator, and by controlling means including a driving device of the moving mechanism, when the material or the mask diameter changes, the energy transmittance or the processing is changed. It is possible to solve the problem that the glass fiber remains due to a difference in threshold value, the processing bottom surface is damaged, and the processing quality cannot be maintained.

[0041]

As described above, according to the present invention, by providing the moving mechanism or the switching mechanism in the collimator, the processing quality such as the form and shape of the processing wall surface can be ensured.
Further, at the time of outputting a short pulse near 1 μS peculiar to a gas laser, the laser pulse waveform avoids an unstable portion, and the energy passing through the mask can be controlled while maintaining a stable waveform of, for example, about 10 μS. And an excellent laser processing apparatus and a processing method capable of obtaining stable processing quality can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a reference example according to the present invention.

FIG. 2 is a luminance distribution diagram of a laser beam in a radial direction in a single mode laser.

FIG. 3 is a configuration diagram showing a second reference example of the present invention.

FIG. 4 is a configuration diagram showing an embodiment of the present invention.

FIG. 5 is a configuration diagram showing a third reference example of the present invention.

FIG. 6 is a configuration diagram showing a conventional laser processing apparatus.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 laser oscillator 2 fixed lens 3 movable lens 4 mask 5 transfer lens 6 workpiece 7 drive device for movable lens 3 8 driver 11 laser oscillator 12 fixed lens 13 first movable lens 14 second movable lens 15 mask 16 transfer lens 17 Workpiece 18 Driving device for the movable lenses 13 and 14 19 Driver 21 Laser oscillator 22, 23 First collimator 24, 25 Second collimator 26 Mask 27 Galvano scanner that scans laser light at a predetermined location 28 f-Θ Lens 29 Workpiece 30 Driving device for switching the two sets of collimators 31 Driving device for moving the collimator in the optical axis direction 32 Driver 41 Laser oscillator 42 Fixed lens 43 First movable lens 44 Second movable lens 45 Mask 46 Transfer lens 47 Processing 48 drive device 50 driver for moving the driving device 49 movable lenses 43 and 44 for switching the movable lens in the optical axis direction

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-327394 (JP, A) JP-A-1-313195 (JP, A) JP-A-2-32390 (JP, U) JP-A-4-327394 64481 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B23K 26/00-26/073 B23K 26/38 G02B 27/09

Claims (7)

(57) [Claims] 1. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, and a transfer disposed between the mask and the workpiece. A lens and at least two collimators between the laser oscillator and the mask, at least one of the lenses constituting the collimator is fixedly arranged on a laser beam, and the remaining lenses are arranged on the laser beam. And a moving means for moving the entire collimator in the optical axis direction. 2. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, and a transfer disposed between the mask and the workpiece. A lens and at least two collimators between the laser oscillator and the mask, one of which has a configuration in which one of the collimators has a configuration in which the laser light diverges and the other has a configuration in which the laser light converges; A laser processing apparatus provided with a moving means for moving the collimator on the laser beam and moving the entire collimator in the optical axis direction. 3. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, and a transfer disposed between the mask and the workpiece. A lens and at least two collimators between the laser oscillator and the mask, at least one of the lenses constituting the collimator is fixedly arranged on a laser beam, and the remaining lenses are arranged on the laser beam. And a moving means for moving the entire collimator in the optical axis direction, and a control means for controlling at least the moving means. 4. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, and a transfer disposed between the mask and the workpiece. A collimator having at least two collimators between the lens and the laser oscillator and the mask, one of which has a configuration in which laser light diverges and the other has a configuration in which laser light converges, and one of the collimators; A laser processing apparatus provided with a moving means for moving the laser beam on the laser beam and moving the entire collimator in the optical axis direction, and a control means for controlling at least the moving means. 5. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, and a transfer disposed between the mask and the workpiece. A collimator having at least two collimators between the lens and the laser oscillator and the mask, one of which has a configuration in which laser light diverges and the other has a configuration in which laser light converges, and one of the collimators; Moving the laser beam on the laser beam, moving the entire collimator in the optical axis direction, and moving the entire collimator in the optical axis direction, and laser processing provided with control means for controlling at least the moving unit. apparatus. 6. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, a transfer lens disposed between the mask and the workpiece, and Using a laser processing apparatus provided with two or more collimators between the laser oscillator and the mask, at least one of the collimators on a laser beam
Move and move the entire collimator in the optical axis direction
A laser processing method comprising the steps of: 7. A laser oscillator for outputting a laser beam, a mask disposed between the laser oscillator and a workpiece processed by the laser beam, a transfer lens disposed between the mask and the workpiece, and Using a laser processing apparatus having two or more collimators between the laser oscillator and the mask, one is configured to diverge the laser light, and the other is arranged with a collimator configured to converge the laser light, and A laser processing method comprising moving one of the collimators onto the laser beam and moving the entire collimator in the optical axis direction.