JP2020037130A - Laser processing device and laser processing method - Google Patents

Abstract

To enhance circularity of a processed hole while enhancing drilling efficiency.SOLUTION: A laser processing device that performs drilling is provided with: first and second AODs 2 and 3 in which laser beams are sequentially incident and which respectively deflect the beams at angles corresponding to frequencies of input ultrasonic and emit the beams; first and second galvano-scanners 6 and 7, combined to each other so that galvano mirrors turn around shaft lines perpendicular to each other, in which laser beams from the second AOD are incident sequentially and which respectively deflect the beams by the galvano mirrors; a first lens optical system 12 that positions a scanning focal point of the first AOD of the lase beams from the first AOD at a position of the second AOD; a second lens optical system 5 that positions the scanning focal point of the first AOD of the laser beams from the second AOD and the scanning focal point of the second AOD in the vicinities respectively of the first and second galvano scanners; and a fθ lens 8 that makes the laser beams from the second galvano scanner converge to an object to be processed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laser processing apparatus and a laser processing method for performing fine drilling by irradiating a processing target with a laser beam.

  In recent years, in the technical field of printed wiring boards, in order to meet the demand for higher density of electronic circuits, forming a multilayer printed wiring board by laminating a plurality of build-up layers on a core substrate or a support plate. Has been proposed.

  The build-up layer is usually composed of an interlayer insulating layer and a conductive layer thereover.In a multilayer printed wiring board, the conductive layer between the core substrate and the build-up layer and the conductive layer between the build-up layers are electrically connected. Is formed in the interlayer insulating layer, and a via-hole conductor is provided in the through-hole by plating or the like.

  The through-holes for via-hole conductors are extremely small in diameter and large in number, and the formation of the through-holes has recently been performed by laser beam irradiation by a laser processing apparatus as described in Patent Document 1, for example. .

  The upper part of FIG. 6 schematically shows a configuration of an image forming optical system of a conventional laser processing apparatus of this kind. This laser processing apparatus has a flat processing object to be an interlayer insulating layer of a printed wiring board. The object W is irradiated with a laser beam B of carbon dioxide gas to perform fine drilling. The laser beam B from a laser light source such as a carbon dioxide laser is passed through the opening of the first aperture grill 1 to form a beam. A first and second AOD (acousto-optical deflector) 2 for shaping the cross-sectional shape and then deflecting the laser beam B in two axial directions orthogonal to each other at an angle corresponding to the frequency of the inputted ultrasonic wave. 3 and sequentially deflects two-dimensionally to scan the minute rectangular area with the laser beam B. At this time, a half-wave plate (not shown) located between the first and second AODs 2 and 3 But from the first AOD2 The polarization direction of shines laser beam B is rotated by 90 degrees to match the incident to the second AOD3.

  Next, the laser beam B that scans within the minute rectangular area is enlarged in diameter by the lens optical system 5 while blocking the zero-order light from the second AOD 3 by the mask 4, and then the aperture of the second aperture grill (not shown) is opened. To form a cross-sectional shape of the beam, and then sequentially passes the laser beam B to first and second galvanometer scanners 6 and 7 for rotating a galvanometer mirror with a motor around support shafts extending at right angles to each other. The laser beam B is used to deflect two-dimensionally by the reflection of the galvanomirror, and the small rectangular area scanned by the laser beam B is moved in a larger small rectangular area. Scan with beam B.

  Next, the laser beam B that scans the entire small rectangular area is passed through the fθ lens 8 to irradiate the surface of the object W perpendicularly and converge at a position near the surface of the object W. Then, a table (not shown) supporting the workpiece W is moved two-dimensionally, and the small rectangular area scanned by the laser beam B is moved over the entire drilling processing area on the surface of the workpiece W.

  A conventional laser processing apparatus forms a minute through hole in a processing object with a laser beam by the above configuration, so that a very small diameter and a large number of through holes can be formed over the entire processing range of the surface of the processing object. Drilling is performed in a short time, and high throughput of drilling is achieved.

JP 2008-049383 A

  By the way, the above-mentioned conventional laser processing apparatus sequentially scans and scans a minute rectangular area by sequentially passing the laser beam B through first and second AODs 2 and 3 which deflect the laser beam B in two orthogonal directions orthogonal to each other. Since the drilling is performed, as shown in the lower part of FIG. 6 with respect to the scanning optical system of the apparatus, for example, the X-ray of the laser beam emitted from the first AOD 2 is deflected in the X-axis direction as shown in association with the imaging optical system. Axial scanning focal point (deflection center point of laser beam deflected in the X-axis direction) FX and Y-axis scanning focal point (laser beam deflected in the Y-axis direction) of the laser beam that has exited the second AOD 3 to be deflected in the Y-axis direction, for example 6 is shifted in the front-rear direction on the optical axis (scanning center optical axis) of the undeflected laser beam indicated by the broken line in FIG. 6, and in particular, the first AOD2 and the second AOD3 1/2 in between Since the long plate is arranged, the first AOD 2 and the second AOD 3 are separated from each other by at least the thickness of the half-wave plate, so that the X-axis scanning focus FX and the Y-axis scanning focus FY Deviation is inevitable.

  For example, the X-axis scanning focal point FX of the laser beam emitted from the first AOD2 that deflects in the X-axis direction and the Y-axis scanning focal point FY of the laser beam emitted from the second AOD3 that deflects in the Y-axis direction are large. If it is deviated, even if the first and second galvanometer scanners 6 and 7 are arranged in the middle between the X-axis scanning focal point FX and the Y-axis scanning focal point FY, the X- and Y-axis scanning focal points FX and FY cannot be used. The distance increases.

  Thus, as shown on the left side of FIG. 7, the deflected laser beam from the swing axis of the galvanometer mirrors of the first and second galvanometer scanners 6 and 7 arranged on the optical axis of the undeflected laser beam. As shown in the right side of FIG. 7, a part of the cross section of the laser beam B deviates from the reflection surface of the galvanometer mirrors of the first and second galvanometer scanners 6 and 7, and the processing shifts. The intensity of the laser beam B applied to the object W decreases, and the beam cross-sectional shape is deformed from a perfect circle. To avoid this, if the galvanometer mirror is enlarged, the inertia of the galvanometer mirror increases and the galvanometer scanner 6, 7, there is a problem that the scanning speed of the laser beam B is reduced and the machining efficiency of the drilling is reduced.

  If the X-axis scanning focal point FX of the laser beam that has exited the first AOD 2 and the Y-axis scanning focal point FY of the laser beam that has exited the second AOD 3 are significantly deviated, as shown in FIG. Each of the X-axis scanning focal point FX and the Y-axis scanning focal point FY from the center of the opening of the second aperture grill indicated by reference numeral 9 in FIG. 8 is located between the AOD 3 and the first galvano scanner 6. Since the center shift amounts ASX and ASY increase and the laser beam B at least partially deviates from the opening of the second aperture grill 9, the roundness of the laser beam B incident on the fθ lens 8 decreases. Further, there is a problem that the roundness of a through hole to be drilled by the laser beam B incident on the surface of the workpiece W from the fθ lens 8 is reduced.

The laser processing apparatus of the present invention performs a fine drilling process by irradiating a laser beam to a processing target,
The laser beams emitted from the laser light source are arranged in series on the optical path of the laser beam, and the laser beams are sequentially incident, and deflected in two axial directions orthogonal to each other at an angle according to the frequency of the inputted ultrasonic wave. A first AOD and a second AOD;
While being arranged in series with each other, the galvanomirrors are combined so as to rotate around axes perpendicular to each other, and laser beams emitted from the second AOD are sequentially incident, and the laser beams are respectively applied by the galvanomirrors. A first galvano scanner and a second galvano scanner, which are deflected by the reflection of
The laser beam emitted from the first AOD is disposed on the optical path of the laser beam between the first AOD and the second AOD, and the scanning focus of the laser beam emitted from the first AOD in the deflection direction of the first AOD is set to the position of the second AOD. Or a first lens optical system located in the vicinity thereof,
The laser beam emitted from the second AOD is arranged on the optical path of the laser beam between the second AOD and the first galvano scanner, and the scanning focal point of the laser beam emitted from the second AOD in the deflection direction of the first AOD and the second AOD. A second lens optical system that positions a scanning focal point in a deflection direction at or near one of the first galvano scanner and the second galvano scanner;
An fθ lens that causes a laser beam emitted from the second galvano scanner to be perpendicularly incident on a processing object and converge at a position of the processing object;
It is equipped with.

Further, the laser processing method of the present invention is a method of performing a fine drilling process by irradiating a laser beam to the workpiece,
Laser beams emitted from the laser light source are arranged in series on the optical path of the laser beam, and the laser beams are sequentially incident on the first AOD and the second AOD. Deflecting and emitting at an angle corresponding to the frequency of each input ultrasonic wave,
Scanning of the laser beam emitted from the first AOD in the deflection direction of the first AOD by a first lens optical system disposed on the optical path of the laser beam between the first AOD and the second AOD. Placing the focal point at or near the position of the second AOD;
The laser beams emitted from the second AOD are arranged in series on the optical path of the laser beam emitted from the second AOD, and are combined so that the galvanomirrors rotate about axes perpendicular to each other. The first and second galvano-scanners and the second galvano-scanner that irradiate the laser beam by deflecting the laser beam by reflection on a galvanomirror, and emitting the laser beam;
The second lens optical system disposed on the optical path of the laser beam between the second AOD and the first galvanometer scanner allows the laser beam emitted from the second AOD to be deflected in the direction of deflection of the first AOD. The scanning focal point and the scanning focal point in the deflection direction of the second AOD are set at or near one of the first galvano scanner and the second galvano scanner, respectively, preferably the first galvano scanner and the second galvano scanner. To be located between
Making the laser beam emitted from the second galvano scanner perpendicularly incident on the object to be processed by the fθ lens, and converging the laser beam at the position of the object to be processed;
Contains.

  According to the embodiment of the present invention, the laser beam emitted from the laser light source and two-dimensionally deflected by the first and second AODs is incident on the first and second galvano scanners, and these galvano scanners are used. The laser beam is two-dimensionally deflected and emitted in a larger range by the galvanomirror, and the laser beam is perpendicularly incident on the object by the fθ lens and converges at the position of the object. Thereby, fine through holes can be formed in the object to be processed, and fine holes are formed in a short time over a whole area of the surface of the object W to be drilled with a small number of through holes. be able to.

  In addition, according to the embodiment of the present invention, the first lens optical system disposed between the first and second AODs serves to change the direction of deflection of the laser beam emitted from the first AOD in the direction of deflection of the first AOD. Since the scanning focal point is located at or near the position of the second AOD, the laser beam emitted from the second AOD is transmitted to the first galvano scanner and the second galvano scanner by the second lens optical system. The scanning focal point in the deflection direction of the first AOD together with the scanning focal point in the deflection direction of the second AOD is placed at or near one of the positions, preferably between the first galvano scanner and the second galvano scanner. Will have.

  Therefore, the amount of deviation of the laser beam from the rotation axis of each of the galvanometer mirrors of the first and second galvanometer scanners is reduced, and the laser beam can be transmitted to the first and second galvanometers without expanding the galvanometer mirror. Since each of the scanners falls within the reflection surface of each galvanometer mirror without deviating from the reflection surface, the first and second galvanometer scanners can be operated at the same time while avoiding a decrease in the operation speed of the first and second galvanometer scanners due to an increase in the inertial mass of the galvanometer mirror. The maximum deflection angle by each of the second AODs can be effectively used to improve the drilling processing efficiency, and the roundness of the cross-sectional shape of the laser beam incident on the fθ lens can be improved, and the fθ While maintaining the intensity of the laser beam incident on the surface of the workpiece from the lens, the roundness of the through hole drilled with the laser beam is increased. Can be

  Further, when the aperture grill is located on the optical path of the laser beam between the second AOD and the first galvano scanner, the scanning focal point in the deflection direction of the second AOD and the deflection direction of the first AOD are changed. Since the amount of shift of the scanning focal point from the aperture of the aperture grille becomes small and the laser beam falls within the aperture of the aperture grille, the roundness of the cross-sectional shape of the laser beam incident on the fθ lens is improved. Thus, while maintaining the intensity of the laser beam incident on the surface of the object to be processed from the fθ lens, it is possible to increase the roundness of the through hole to be drilled with the laser beam.

FIG. 2 is an explanatory diagram showing an image forming optical system and a scanning optical system of an embodiment of the present invention in an upper part and a lower part in association with each other. The position of the scanning focal point on the optical axis of the undeflected laser beam of the laser beam deflected by the first lens optical system of the laser processing apparatus of the embodiment shown in FIG. FIG. 9 is an explanatory diagram showing the relations between and. FIG. 2 is an explanatory diagram illustrating an example of a specific arrangement of each unit of the laser processing apparatus of the embodiment illustrated in FIG. 1. FIG. 2 is an explanatory diagram showing a positional relationship between a laser beam in the scanning optical system shown in FIG. 1 and a reflecting surface of a galvanomirror. FIG. 2 is an explanatory diagram showing a positional relationship between a laser beam in the scanning optical system shown in FIG. 1 and an opening of a second aperture grill. It is explanatory drawing which shows the image forming optical system and the scanning optical system of the conventional laser processing apparatus in upper part and lower part in connection with each other. FIG. 7 is an explanatory diagram showing a positional relationship between a laser beam in the scanning optical system shown in FIG. 6 and a reflecting surface of a galvanomirror. FIG. 7 is an explanatory diagram showing a positional relationship between a laser beam in a scanning optical system shown in FIG. 6 and an opening of a second aperture grill.

  Hereinafter, embodiments of a laser processing apparatus and a laser processing method according to the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing an imaging optical system and a scanning optical system of an laser processing apparatus according to an embodiment of the present invention in an upper part and a lower part in relation to each other.

  The laser processing apparatus of this embodiment performs a fine drilling process with a diameter of several tens of μm by irradiating a carbon dioxide laser beam B to a flat workpiece W to be an interlayer insulating layer of a printed wiring board. 6, a first aperture grill 1, a first AOD (acousto-optic deflector) 2 and a second AOD (acousto-optic deflector) 3 arranged in series with each other, as in the conventional laser processing apparatus shown in FIG. And a second lens optical system (here, for convenience, denoted by the same reference numeral as a lens optical system in a conventional laser processing apparatus) 5 as an optical system having a mask 4, and a second aperture grill 9, which are arranged in series with each other. A first galvano scanner 6 and a second galvano scanner 7 and a normal fθ lens 8.

  The first aperture grill 1 passes a laser beam B emitted from a laser light source (not shown) through an opening, forms the laser beam B into a cross-sectional shape corresponding to the shape of the opening, and then enters the first AOD 2.

  The first AOD 2 diffracts the incident laser beam B by a crystal in a predetermined plane including an incoming / outgoing optical path and emits a first-order diffracted light, and simultaneously converts the first-order diffracted light into the crystal in the predetermined plane. Is deflected to an angle corresponding to the frequency of the input ultrasonic wave, and is incident on the next second AOD 3. The second AOD 3, like the first AOD 2, includes the incident laser beam B by a crystal and includes an input / output optical path. A first-order diffracted light is emitted by diffracting the light in a predetermined plane, and the first-order diffracted light is emitted at a high speed and deflected in the predetermined plane at an angle corresponding to the frequency of the ultrasonic wave input to the crystal.

  Here, the first AOD2 and the second AOD3 are arranged such that their predetermined planes extend in the X-axis direction and the Y-axis direction, respectively, and the predetermined planes are positioned at right angles. The laser beam B is two-dimensionally deflected in the X-axis and Y-axis directions in the rectangular coordinate system of the laser processing apparatus, and scans a minute area on the surface of the workpiece W with the laser beam B.

  The second lens optical system 5 blocks the 0th-order diffracted light emitted together with the 1st-order diffracted light from the second AOD 3 with the mask 4 functioning as a damper, and also converges the laser beam B converged at the position of the workpiece W. Functioning as an expander for reducing the beam diameter of the laser beam of the first order diffracted light emitted from the second AOD 3 by a combination of two lenses having different focal lengths. Let it. Then, the second aperture grill 9 located between the second lens optical system 5 and the first galvano scanner 6 passes the laser beam B expanded in diameter by the second lens optical system 5 through the opening. After shaping the cross-sectional shape of the beam, the beam is incident on a galvanometer mirror of the first galvanometer scanner 6.

  The first galvano scanner 6 rotates the galvanomirror about a predetermined axis in response to the drive signal, deflects the incident laser beam B by reflection on the reflection surface of the galvanomirror, and performs the next second galvano mirror. The laser beam B is made incident on the scanner 7, and the second galvano scanner 7 rotates the galvanomirror about a predetermined axis in response to the drive signal in the same manner as the first galvano scanner 6, and the incident laser beam B is transmitted to the galvanomirror. The light is deflected by the reflection on the reflection surface and emitted.

  Here, the first galvano scanner 6 and the second galvano scanner 7 are arranged such that predetermined rotation axes of the galvanomirrors are at right angles to each other, so that the laser beam B is emitted from the laser processing apparatus. A small rectangle that is two-dimensionally deflected in the X-axis direction and the Y-axis direction in the rectangular coordinate system and is wider than the minute rectangle area on the surface of the workpiece W that is scanned by the first AOD2 and the second AOD3. The small rectangular area is moved within the area.

  lens 8 is arranged toward the workpiece W and emitted from the second galvano scanner 7 regardless of the position of the laser beam B on the reflecting surface of the galvanometer mirror of the second galvano scanner 7. The laser beam B is perpendicularly incident on the surface of the processing object W and converges at a position near the surface of the processing object W.

  Further, as shown in FIG. 1, the laser processing apparatus of this embodiment has a half wavelength intervening between the first AOD 2 and the second AOD 3 as shown in FIG. The half-wave plate 10 rotates the polarization direction of the laser beam B emitted from the first AOD 2 by 90 degrees so as to be suitable for incidence on the second AOD 3.

  Further, as shown in FIG. 1, the laser processing apparatus of this embodiment includes another mask 11 interposed between the first AOD 2 and the second AOD 3, and this mask 11 Like the mask 4, the first AOD 2 functions as a damper for blocking the 0th-order diffracted light emitted together with the 1st-order diffracted light.

  By the way, in the conventional laser processing apparatus, since at least the half-wave plate is provided between the first AOD 2 and the second AOD 3 as described above, as shown in the upper part of FIG. The distance DC between the first AOD 2 and the second AOD 3 is large. For this reason, as shown in the lower part of FIG. 6, between the X-axis scanning focal point FX and the Y-axis scanning focal point FY at the maximum deflection angle by each of the first AOD2 and the second AOD3 in FIG. 7, the distance DF of the undeflected laser beam in the direction of the optical axis (scanning center optical axis) of the undeflected laser beam increases, and the laser beam from the reflecting surfaces of the X and Y axis galvanometer mirrors 6 and 7 shown on the right side of FIG. The beam B deviates, and the laser beam B deviates from the opening of the second aperture grill 9 as shown on the right side of FIG.

  On the other hand, the laser processing apparatus of this embodiment includes a first lens optical system 12 between the first AOD 2 and the second AOD 3, as shown in FIG. The lens optical system 12 includes, for example, a first lens 13 and a second lens 13 formed of convex lenses having the same specifications as each other, as shown in the upper and lower parts of FIG. Are combined at a distance 2A that is twice as long as the focal length A of the lenses, and the first lens 13 is located at the rear side of the first AOD2 in the optical path direction from the first AOD2 to the focal length A of the first AOD2. The second lens 14 is arranged at a position on the optical path front side with respect to the second AOD 3 and at a focal distance A from the second AOD 3.

  According to the first lens optical system 12, the laser beam B that has been deflected and emitted from the first AOD 2 is parallel to the optical axis (scanning center optical axis) of the undeflected laser beam by the first lens 13. The beam is directed to the second lens 14 and then enters the second AOD 3 at the focal position of the second lens 14, so that the X-axis scanning focal point FX by the first AOD 2 is shifted to the second AOD 3. Position.

  Therefore, as shown in FIG. 1, the undeflected laser beam between the X-axis scanning focal point FX and the Y-axis scanning focal point FY at the maximum deflection angle by each of the first AOD2 and the second AOD3. The distance DF in the direction of the optical axis (scanning center optical axis) becomes extremely small or substantially 0 (zero), so that the X-axis scanning focal point FX and the Y-axis scanning focal point FY coincide with each other. Both the focal point FX and the Y-axis scanning focal point FY are located in the vicinity of the first and second galvano scanners 6 and 7, or although not shown, both the X-axis scanning focal point FX and the Y-axis scanning focal point FY are both first and second. Since the laser beam B is located between the two galvano scanners 6 and 7, as shown in FIG. 4, the entire laser beam B fits within the reflection surface of the galvanometer mirrors of the X and Y axis galvano scanners 6 and 7. As shown in FIG. Entire laser beam B in the opening of the Chaguriru 9 is within.

  Therefore, according to the laser processing apparatus of this embodiment and the laser processing method of this embodiment in which the laser processing apparatus performs the boring as described above, the processing object W having an extremely small diameter and a large number of through holes is provided. The drilling can be performed in a short time over the entire hole drilling range on the surface of the lens, and the distance DF in the optical axis direction between the X-axis scanning focal point FX and the Y-axis scanning focal point FY becomes extremely small. Or substantially 0 (zero), and since both the X-axis scanning focal point FX and the Y-axis scanning focal point FY are located near the first and second galvano scanners 6 and 7, Since the laser beam B falls within the reflection surfaces of the first and second galvanometer scanners 6 and 7, the maximum deflection angle by each of the X-axis AOD2 and the Y-axis AOD3 is effectively used to improve the drilling processing efficiency. Can be In addition, since the laser beam B falls within the opening of the second aperture grill 9, the roundness of the laser beam B incident on the fθ lens 8 is improved, and the roundness of the through hole to be drilled is increased. be able to.

  FIG. 3 is an explanatory diagram showing an example of a specific arrangement of each part of the laser processing apparatus of the embodiment shown in FIG. 1. The laser processing apparatus of this example has the components shown in FIG. In addition, the laser processing apparatus of the present embodiment includes a reflecting mirror 15 disposed between the second lens optical system 5 and the second aperture grill 9. After the laser beam B, which has been emitted from the system 5 substantially horizontally, is reflected downward, dropped and passed through the opening of the second aperture grill 9, the laser beam B is sequentially transmitted to the first and second galvano scanners 6, 7. And then irradiates the surface of the workpiece W below the fθ lens 8 via the fθ lens 8.

  Note that the workpiece W here may be moved in a horizontal direction by a table (not shown), and in this case, an extremely small diameter and a large number of through holes are formed in a drilling processing area on the surface of the workpiece W. Fine drilling over the whole can be performed in a shorter time.

  The present invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the scope of the claims. For example, in the laser processing apparatus and the laser processing method of the embodiment, the X-axis scanning focal point FX and the Y-axis scanning focal point FY are both located near or between the first and second galvanometer scanners 6 and 7. Alternatively, both the X-axis scanning focal point FX and the Y-axis scanning focal point FY may be located on the rotation axis of the galvano mirror of the first galvano scanner 6 or the second galvano scanner 7. Alternatively, the X-axis scanning focal point FX may be located on the rotation axis of the galvanomirror of the first galvano scanner 6 and the Y-axis scanning focal point FY may be located on the rotation axis of the galvanomirror of the second galvano scanner 7. Good.

  Further, the two lenses 13 and 14 in the first lens optical system 12 are used in combination in the laser processing apparatus and the laser processing method of the above-described embodiment, with the same focal length. Two lenses having different focal lengths such as the system 5 may be used in combination.

1 First aperture grill 2 First AOD (acousto-optical deflector)
3 Second AOD (acousto-optic deflector)
Reference Signs List 4 mask 5 second lens optical system 6 first galvano scanner 7 second galvano scanner 8 fθ lens 9 second aperture grille 10 1/2 wavelength plate 11 mask 12 first lens optical system 13 first lens 14 Second lens 15 Reflecting mirror B Laser beam FX X-axis scanning focal point FY Y-axis scanning focal point W Workpiece

Claims (4)

A laser processing apparatus that performs a fine drilling process by irradiating a processing object with a laser beam,
The laser beams emitted from the laser light source are arranged in series on the optical path of the laser beam, and the laser beams are sequentially incident, and deflected in two axial directions orthogonal to each other at an angle according to the frequency of the inputted ultrasonic wave. A first AOD and a second AOD;
While being arranged in series with each other, the galvanomirrors are combined so as to rotate around axes perpendicular to each other, and laser beams emitted from the second AOD are sequentially incident, and the laser beams are respectively applied by the galvanomirrors. A first galvano scanner and a second galvano scanner, which are deflected by the reflection of
The laser beam emitted from the first AOD is disposed on the optical path of the laser beam between the first AOD and the second AOD, and the scanning focus of the laser beam emitted from the first AOD in the deflection direction of the first AOD is set to the position of the second AOD. Or a first lens optical system located in the vicinity thereof,
The laser beam emitted from the second AOD is arranged on the optical path of the laser beam between the second AOD and the first galvano scanner, and the scanning focal point of the laser beam emitted from the second AOD in the deflection direction of the first AOD and the second AOD. A second lens optical system that positions a scanning focal point in a deflection direction at or near one of the first galvano scanner and the second galvano scanner;
An fθ lens that causes a laser beam emitted from the second galvano scanner to be perpendicularly incident on a processing object and converge at a position of the processing object;
Equipped. The laser processing apparatus according to claim 1,
The second lens optical system sets a scanning focal point in the first AOD deflection direction and a scanning focal point in the second AOD deflection direction of the laser beam emitted from the second AOD to the first galvano scanner and the second galvano scanner, respectively. Between the two galvanometer scanners. A laser processing method of irradiating a laser beam to a processing target to perform fine drilling processing,
Laser beams emitted from a laser light source are arranged in series on the optical path of the laser beam by a first AOD and a second AOD, which are sequentially incident on the laser beam, in two axial directions orthogonal to each other. Deflecting and emitting at an angle corresponding to the frequency of each input ultrasonic wave,
Scanning of a laser beam emitted from the first AOD in a deflection direction of the first AOD by a first lens optical system disposed on an optical path of the laser beam between the first AOD and the second AOD. Placing the focal point at or near the position of the second AOD;
The laser beams emitted from the second AOD are arranged in series on the optical path of the laser beam emitted from the second AOD, and are combined so that the galvanomirrors rotate about axes perpendicular to each other. The first and second galvano-scanners and the second galvano-scanner that irradiate the laser beam by deflecting the laser beam by reflection on a galvanomirror, and emitting the laser beam;
The second lens optical system disposed on the optical path of the laser beam between the second AOD and the first galvanometer scanner allows the laser beam emitted from the second AOD to be deflected in the direction of deflection of the first AOD. Positioning the scanning focal point and the scanning focal point in the deflection direction of the second AOD at or near one of the first galvano scanner and the second galvano scanner, respectively;
Making the laser beam emitted from the second galvano scanner perpendicularly incident on the object to be processed by the fθ lens, and converging the laser beam at the position of the object to be processed;
Contains. The laser processing method according to claim 3, wherein
The second lens optical system sets the scanning focus in the deflection direction of the first AOD and the scanning focus in the deflection direction of the second AOD of the laser beam emitted from the second AOD to the first galvano scanner and the second galvano scanner, respectively. Between the two galvanometer scanners.