JP2015080799A - Laser processing device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser processing device and a laser processing method, capable of increasing processing speed and reducing cost.SOLUTION: A laser processing device 1 comprises: a forming mask 212 disposed between a light focusing body 200 and a substrate 2, through which a tapered hole 211 becoming narrower continuously as coming close to the substrate 2 in a direction along a light axis is formed, and irradiating a focused laser beam to the substrate 2 for forming an irradiation shape while reflecting a part of the focused laser beam on a side surface of the tapered hole 211; and a mechanism part 213 disposed at at least one of the light focusing body 200 and the forming mask 212, and changing a relative position between the light focusing body 200 and the forming mask 212 so that the irradiation shape becomes a desired shape by reflecting the part of the focused laser beam on the side surface of the tapered hole 211 and irradiating the remnant to the substrate 2.

Description

  The present invention relates to a laser processing apparatus that performs processing such as cutting on a substrate using laser light, and a laser processing method.

  Conventionally, a laser light oscillator that emits laser light, a focus adjustment lens that forms an image of the emitted laser light on the processing surface, and the shape of the laser light imaged on the processing surface is an arbitrary rectangular shape There is known a laser processing apparatus having a mask for shaping and a galvano scanner for scanning the shaped laser beam on a machining surface. This mask has four slit plates, and laser light is shaped into an arbitrary rectangular shape by these slit plates (see, for example, Patent Document 1).

  Moreover, in order to make the laser spot imaged on the substrate which is the processing surface into an elliptical shape, a cylindrical lens is used for the condensing optical system for condensing on the substrate without using the mask disclosed in Patent Document 1. Conventional scribing apparatuses are also known (see, for example, Patent Document 2).

JP 2009-45626 A JP 2011-104633 A

However, the prior art has the following problems.
In the conventional laser processing apparatus disclosed in Patent Document 1, a part of the laser light is shielded by a mask when shaping the laser light. For this reason, there is a problem that the energy of the shielded laser beam does not contribute to processing and leads to a decrease in processing speed.

  Further, the laser light shielded by the mask has a component to be reflected and a component to be absorbed as heat by the slit plate. Therefore, it is necessary to take measures against reflection from the slit plate and measures against heat load on the slit plate, and there is a problem that costs increase.

  Moreover, in the conventional scribing apparatus shown in Patent Document 2, the cylindrical lens is made of a transmissive optical element. For this reason, the influence of the thermal lens is greater than that of a reflective optical element such as a mirror, which may increase the instability of processing. As a result, there is a problem that the processing speed is reduced.

  Furthermore, the shape of the laser spot must always be constant with respect to the processing direction. For this reason, a separate device for rotating the cylindrical lens in accordance with the processing direction is required, which increases the cost. Further, when adjusting the ellipticity of the laser beam, it is necessary to replace the cylindrical lens itself. Therefore, a plurality of cylindrical lenses are required, and this is also expensive.

  The present invention has been made to solve the above-described problems, and an object thereof is to obtain a laser processing apparatus and a laser processing method capable of increasing the processing speed and reducing the cost. .

  A laser processing apparatus according to the present invention includes a laser light oscillator that emits laser light, a light collector that condenses the laser light toward a substrate to be processed, and a light collector disposed between the light collector and the substrate. A tapered hole is formed that narrows continuously as it approaches the substrate in the direction along the optical axis of the laser beam collected by, and a part of the laser beam collected by the collector is reflected by the side surface of the tapered hole. A portion of the laser beam condensed by the condensing body is provided on at least one of a shaping mask, a condensing body, and a shaping mask that shapes the irradiation shape on the substrate by irradiating the substrate. A mechanism that allows the relative position of the condenser and the shaping mask to be changed so that the irradiation shape on the substrate shape is reflected by irradiating the substrate with reflection from the side surface of the tapered hole. , And shaped by a mask for shaping And the laser beam comprises irradiating unit for irradiating the substrate.

  A laser processing method according to the present invention includes a laser light oscillator that emits laser light, a light collector that condenses the laser light toward a substrate to be processed, a light collector that is disposed between the light collector and the substrate, A tapered hole is formed that narrows continuously as it approaches the substrate in the direction along the optical axis of the laser beam collected by, and a part of the laser beam collected by the collector is reflected by the side surface of the tapered hole. It is provided on at least one of the shaping mask, the condensing body, and the shaping mask that shapes the irradiation shape on the substrate by irradiating the substrate, and the relative position between the condensing body and the shaping mask can be changed. A laser processing method applied to a laser processing apparatus including a mechanism unit, an irradiation unit that irradiates a substrate with laser light shaped by a shaping mask, and a movement amount control unit that performs position control of the mechanism unit. , Movement amount control In this case, the irradiation position irradiated onto the substrate has a desired intensity distribution by changing the relative position according to the processing content of the substrate and changing the amount of laser light reflected on the side surface of the tapered hole and irradiating the substrate. So that the position of the mechanism is controlled.

  According to the laser processing apparatus and the laser processing method of the present invention, the laser beam reflected on the tapered hole formed in the shaping mask is all emitted to the irradiation unit side, so that the irradiation shape of the laser beam on the processing surface can be reduced. A shaping mask with a tapered shape of the tapered hole is used so as to have an elliptical shape extending backward in the processing direction, and a function of adjusting the relative position between the shaping mask and the laser beam is provided. As a result, the intensity distribution of the laser beam energy irradiated on the processing surface is made stronger at the front side in the processing direction, and all the energy of the laser beam can be contributed to the processing of the workpiece, resulting in a high processing speed. Can be achieved. Furthermore, since the shape of the laser light irradiated onto the workpiece can be changed with one shaping mask, the cost can be reduced.

It is a schematic diagram which shows the laser processing apparatus by Embodiment 1 of this invention. It is an enlarged view which shows the process head main body of FIG. FIG. 3 is an enlarged view showing an example in which the central axis of the tapered hole is decentered with respect to the light collection optical axis by moving the shaping mask in FIG. 2. It is process drawing which shows the irradiation shape of the laser beam along the AA line of FIG. 3, BB line, and CC line, and intensity distribution of laser beam energy. It is an enlarged view which shows the process head main body of the laser processing apparatus by Embodiment 2 of this invention. It is an enlarged view which shows the process head main body of the laser processing apparatus by Embodiment 3 of this invention. It is a top view of the lens moving mechanism part shown in FIG. It is a schematic diagram which shows the injection of the processing gas when the optical axis is decentered by moving the processing lens by the lens movement amount control unit in the second embodiment of the present invention. It is an enlarged view which shows the process head main body of the laser processing apparatus by Embodiment 4 of this invention. It is an expanded sectional view which shows the irradiation part of FIG.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram showing a laser processing apparatus according to Embodiment 1 of the present invention. The laser processing apparatus 1 according to the first embodiment is an apparatus that melts and processes a workpiece (substrate) 2 with laser light. As shown in FIG. 1, the laser processing apparatus 1 includes a laser beam oscillator 3 that emits laser light, a transmission optical system 4 that transmits the emitted laser beam, and a laser beam that is transmitted. It has a processing head main body 10 that irradiates a workpiece (substrate) 2 and a gas supply device 5 that supplies a processing gas that is ejected together with a laser beam irradiated to the workpiece 2. Here, a metal is used for the workpiece 2.

In the laser oscillator 3, for example, the type and output of the laser are properly used depending on the thickness and type of the workpiece 2 to be processed. In general, a gas laser light source such as a CO ₂ laser or a solid-state laser light source such as a YAG laser is used for the laser light oscillator 3. In this example, a laser beam oscillator 3 in which the shape of the laser beam emitted from the laser beam oscillator 3 is approximately circular is used.

  The transmission optical system 4 transmits the laser light emitted from the laser light oscillator 3 to the processing head main body 10. In this example, the laser beam emitted from the laser beam oscillator 3 is reflected and transmitted by the reflection mirror 4a. Although FIG. 1 illustrates the case where one reflection mirror 4a is used, a plurality of reflection mirrors 4a may be used depending on the positional relationship between the laser light oscillator 3 and the processing head body 10. . When a solid-state laser light source such as a YAG laser is used as the laser light oscillator 3, the laser light may be transmitted through an optical fiber.

  The laser beam transmitted by the transmission optical system 4 is applied to the workpiece 2 from the processing head body 10. At this time, it is necessary to blow away the molten metal of the work 2 melted by the laser beam. Therefore, the processing gas supplied from the gas supply device 5 is jetted from the processing head body 10 to the workpiece 2 together with the laser beam.

  The gas supply device 5 includes a gas cylinder 5 a and a gas pipe 5 b having one end connected to the gas cylinder 5 a and the other end connected to the processing head body 10. The processing gas output from the gas cylinder 5a is supplied to the processing head main body 10 through the gas pipe 5b, and is jetted from the processing head main body 10 toward the workpiece 2 together with the laser beam.

  FIG. 2 is an enlarged view showing the processing head body 10 of FIG. As shown in FIG. 2, the processing head main body 10 irradiates the workpiece 2 with the processing head unit 20 that condenses the laser light transmitted by the transmission optical system 4 and the laser light condensed by the processing head unit 20. And an irradiating unit 30.

  Further, the processing head unit 20 includes a processing lens (condenser) 200 that condenses the laser light transmitted by the transmission optical system 4 toward the work 2, and the laser light condensed by the processing lens 200. 2 has a laser shape shaping section 210 (hereinafter simply referred to as “shaping section 210”) for shaping into a shape to be irradiated.

  The processing lens 200 is a condensing lens that can condense laser light. Since the substantially circular laser light is emitted from the laser light oscillator 3, the shape of the laser light condensed by the processing lens 200 is also substantially circular. Further, the processing lens 200 is held by a lens movement control device (not shown), and the direction along the optical axis direction of the laser beam transmitted by the transmission optical system 4 (the vertical direction shown in FIG. 2). It can be displaced in the double arrow. Thereby, the processing lens 200 can change the focal length of the laser light irradiated to the processing surface 2a on the workpiece 2. The substantially circular laser beam condensed by the processing lens 200 is shaped into an irradiation shape by the shaping unit 210.

  The laser beam is shaped by the shaping unit 210 in order to prevent processing defects. For example, taking the process of cutting the workpiece 2 as an example, the cutting proceeds by melting by laser light irradiation and discharging of the melt by the processing gas. At this time, the laser beam ahead in the machining direction plays a role of melting the workpiece 2, and the laser beam behind the machining direction plays a role of supplying heat to the workpiece 2.

  As the cutting of the workpiece 2 proceeds, the discharge trace of the melt of the workpiece 2 becomes a drag line and appears on the processed cut surface. Since the viscosity of the workpiece 2 has a negative correlation with the temperature, the viscosity of the workpiece 2 increases when a sufficient amount of heat cannot be supplied to the workpiece 2. Along with this, the time required for discharging the melt of the workpiece 2 increases, so that the drag line is delayed with respect to the processing direction as it goes to the lower part of the cut surface. When this delay exceeds a certain level, processing defects and cutting defects occur.

  Further, as the processing speed increases, the irradiation time of the laser beam behind the processing direction necessary for maintaining the temperature of the workpiece 2 is shortened. In this case, the viscosity of the workpiece 2 is increased, the drag line is delayed, and machining failure occurs. In order to prevent this, it is necessary to shape the shape of the laser light applied to the workpiece 2 to an optimum shape according to the processing of the workpiece 2.

  Therefore, the shaping unit 210 according to the first embodiment includes a shaping mask 212 including a tapered hole 211, a mask moving mechanism unit 213 provided in the shaping mask 212, and a mask for shaping into an optimal irradiation shape. A mask movement amount control unit 214 that controls the position of the movement mechanism unit 213 is provided.

  The shaping mask 212 has a plate shape, and a processing lens is provided at the center of the shaping mask 212 in the direction along the optical axis (condensing optical axis) of the laser light collected by the processing lens 200. A tapered hole 211 that is continuously narrowed from the 200 side toward the irradiation unit 30 side (work 2 side) (work 2) is provided. In this example, the hole shape of the taper hole 211 is substantially circular, and as the material of the shaping mask 212, a highly reflective material that reflects laser light is used. In addition, the shaping mask 212 can be changed in relative position with the processing lens 200 by the mask moving mechanism unit 213.

  The mask moving mechanism unit 213 is attached to the shaping mask 212. The mask moving mechanism unit 213 changes a relative position between the shaping mask 212 and the processing lens 200 to reflect a part of the laser light collected from the processing lens 200 at the tapered hole side surface 211a. Thereby, the shape of the laser beam irradiated on the board | substrate 2 is changed so that it may become a desired shape.

  A mask movement amount control unit 214 is connected to the mask movement mechanism unit 213, and the position of the mask movement mechanism unit 213 is controlled. The position at which all the laser light condensed by the processing lens 200 passes through the tapered hole 211 to the irradiation unit 30 side between the processing lens 200 and the irradiation unit 30 by the position control by the mask movement amount control unit 214. Can be adjusted.

  Specifically, the mask movement amount control unit 214 controls the mask movement mechanism unit 213 attached to the shaping mask 212 to thereby make a direction (shown in FIG. 2) orthogonal to the laser beam condensing optical axis direction. In addition, the shaping mask 212 can be moved in the left-right direction). Accordingly, the mask movement amount control unit 214 changes the relative position between the shaping mask 212 and the processing lens 200 according to the processing content of the substrate 2.

  As a result, the mask movement amount control unit 214 can control the amount of eccentricity of the central axis of the tapered hole 211 of the shaping mask 212 (corresponding to the movement amount of the shaping mask 212) with respect to the converging optical axis. The amount of laser light applied to the substrate 2 can be changed, and an irradiation shape having a desired intensity distribution can be formed on the processed surface.

  That is, the mask movement amount control unit 214 moves the position of the shaping mask 212 on a plane orthogonal to the condensing optical axis, so that a part of the laser light is applied to the tapered hole side surface 211a and irradiated. It can be pulled out to the part side.

  The mask movement amount control unit 214 sets the central axis of the tapered hole 211 and the condensing optical axis according to the processing content of the workpiece 2 with reference to the state where the central axis of the tapered hole 211 and the condensing optical axis coincide with each other. Determine the amount of eccentricity. It should be noted that the amount of eccentricity is such that even if a part of the laser light hits the tapered hole side surface 211a and is reflected by the central axis of the tapered hole 211 being decentered from the condensing optical axis, the reflected laser light is directed to the processing lens 200 side. It is determined within a range where it can escape to the irradiation unit 30 side without returning.

  Therefore, the shaping mask 212 is disposed at a position where all of the laser light condensed by the processing lens 200 including the laser light reflected by the tapered hole side surface 211 a passes through the tapered hole 211. Note that the mask movement amount control unit 214 can appropriately change the amount of eccentricity between the central axis of the tapered hole 211 and the converging optical axis even during processing so as to be in an optimum state for processing the workpiece 2.

  Here, a method in which the laser light is deformed into a shape suitable for processing the workpiece 2 by the shaping unit 210 will be specifically described with reference to the drawings. FIG. 3 is an enlarged view showing an example in which the central axis of the tapered hole 211 is decentered with respect to the light collection optical axis by moving the shaping mask 212 in FIG. FIG. 4 is an explanatory diagram showing the irradiation shape of the laser light and the intensity distribution of the laser light energy along the lines AA, BB, and CC in FIG.

  In FIG. 3, the shaping mask 212 has a processing direction indicated by an arrow D with respect to a reference state in which the central axis of the tapered hole 211 coincides with the converging optical axis by the mask moving mechanism unit 213. Is moved in the opposite direction (rear in the processing direction, left direction in FIG. 3). Therefore, the central axis of the tapered hole 211 is shifted rearward in the processing direction with respect to the light collecting optical axis. Thereby, a part of the laser beam condensed by the processing lens 200 on the front side in the processing direction hits and is reflected by the tapered hole side surface 211a. At this time, the reflected laser light is reflected rearward in the processing direction by the inclined tapered hole side surface 211a and exits to the irradiation unit 30 side.

  Since the AA line in FIG. 3 is a position above the shaping mask 212, as shown in FIG. 4A, the shape of the laser light remains a substantially circular shape condensed by the processing lens 200. It is. At this time, the intensity distribution of the laser beam energy is strong at the center of the circle, and the intensity decreases as it goes in the radial direction of the circle.

  Further, in FIGS. 4B and C corresponding to the BB line and the CC line in FIG. 3, the laser light has passed through the tapered hole 211 of the shaping mask 212, respectively. Therefore, the laser beam ahead in the processing direction is reflected on the tapered hole side surface 211a. Thereby, the shape of the laser beam becomes an ellipse extending backward in the processing direction. The shape of the laser beam is an elliptical shape extending backward in the processing direction as the distance from the shaping mask 212 increases. At this time, the intensity distribution of the laser beam energy has a steep gradient of the intensity distribution on the front side in the processing direction, and it can be seen that the intensity on the front side in the processing direction is strong.

  As described above, the laser light shaped by the shaping unit 210 is irradiated toward the workpiece 2 from the irradiation unit 30 together with the processing gas.

  Next, a method in which the laser beam emitted from the laser beam oscillator 3 is irradiated from the irradiation unit 30 will be described. The laser light emitted from the laser light oscillator 3 is transmitted to the processing head main body 10 via the transmission optical system 4. The laser beam transmitted through the transmission optical system 4 is collected by the processing lens 200.

  At this time, the mask movement amount control unit 214 controls the mask movement mechanism unit 213 so as to make the irradiation shape of the laser light optimal for processing the workpiece 2. Specifically, the mask movement amount control unit 214 changes the relative position of the shaping mask 212 and the processing lens 200 to decenter the central axis of the tapered hole 211 and the condensing optical axis. The unit 213 is controlled.

  When the laser beam condensed by the processing lens 200 passes through the shaping mask 212 moved by the mask moving mechanism unit 213, a part of the laser beam is reflected by the tapered hole 211 and irradiated onto the substrate 2. Can be changed. At the same time, the laser beam condensed by the processing lens 200 is transformed into an irradiation shape having a desired intensity distribution. Thereby, the irradiation shape of the laser beam is shaped into an optimum shape for processing the workpiece 2. The laser beam transformed into a shape suitable for processing the workpiece 2 by the shaping unit 210 is irradiated from the irradiation unit 30 onto the processing surface 2a of the workpiece 2 together with the processing gas.

  As described above, the laser processing apparatus according to the first embodiment has a configuration in which even if the laser light hits the tapered hole side surface 211a and is reflected, all the reflected laser light can escape to the irradiation unit 30 side. . As a result, it is possible to eliminate blocking of a part of the energy of the laser beam during the laser beam shaping as in the prior art. As a result, the energy of all the laser beams emitted from the laser beam oscillator 3 can be contributed to the processing of the workpiece 2. Furthermore, since all the energy of the laser beam contributes to the machining of the workpiece 2, the machining speed can be increased.

  Further, the position of the mask moving mechanism unit 213 is controlled by the mask moving amount control unit 214 so that the amount of eccentricity between the central axis of the tapered hole 211 and the converging optical axis becomes an optimum state for processing the workpiece 2. It can be changed as appropriate even during processing. As a result, the irradiation shape of the laser light can be changed to an optimum shape for processing the workpiece 2 according to the processing content.

  For example, when performing the piercing process (drilling process) of the workpiece 2, the cutting process is performed by using a normal substantially circular laser beam in which the central axis of the tapered hole 211 coincides with the converging optical axis. In this case, the center axis of the tapered hole 211 and the condensing optical axis are decentered, and it becomes possible to perform using an elliptical laser beam extending in the processing direction.

  As another example, in the same machining process, the amount of eccentricity between the central axis of the tapered hole 211 and the converging optical axis can be reduced in the corner portion where the speed decreases. Thereby, the reduction | decrease of a processing speed can be suppressed by suppressing the ratio extended | stretched back to a process direction, and concentrating energy in a narrow range. On the other hand, in the straight portion where the processing speed is high, the amount of eccentricity between the central axis of the tapered hole 211 and the converging optical axis can be increased. Thereby, the irradiation time which hits the workpiece | work 2 can be lengthened by increasing the ratio extended | stretched back to a process direction. As a result, processing defects of the workpiece 2 can be suppressed even when the processing speed is increased.

  In addition, a configuration is provided in which the relative position of the shaping mask 212 formed of a highly reflective material with respect to the processing lens can be variably controlled so that all of the laser light reflected by the tapered hole side surface 211a passes to the irradiation unit 30 side. As a result, it is not necessary to take a countermeasure against reflection and a countermeasure against the thermal load of the shaping mask 212 as in the prior art. As a result, the cost can be reduced.

  Further, the position control of the shaping mask so that the amount of eccentricity between the central axis of the tapered hole 211 and the converging optical axis is optimized in accordance with the processing of the workpiece 2 is executed by changing the amount of eccentricity appropriately even during processing. It is possible. By realizing such position control, the irradiation shape of the laser light can be easily changed without replacing the lens itself as in the prior art. As a result, the cost can be reduced by using a plurality of lenses, and the labor of exchanging lenses by an operator can be saved.

  Further, as described above, the technical feature of the present application that makes it possible to appropriately change the amount of eccentricity can be used for applications other than setting an appropriate amount of eccentricity according to the type of processing or the speed during the same processing. . For example, the amount of eccentricity can be adjusted to an appropriate value depending on the material of the workpiece 2 or the mode and intensity distribution of the laser beam emitted from the laser beam oscillator 3.

  As described above, according to the first embodiment, there is provided a configuration in which the relative position of the shaping mask having a tapered hole with respect to the processing lens is variably controlled on a plane orthogonal to the converging optical axis. By providing such a configuration, the energy of all the laser beams can be used for processing, and the irradiation shape of the laser beams on the processing surface can be appropriately changed according to the processing content. As a result, the processing speed can be increased and the cost can be reduced.

Embodiment 2. FIG.
In the first embodiment, the case where the shaping mask 212 can be moved only on a plane orthogonal to the converging optical axis when adjusting the relative position between the processing lens 200 and the shaping mask 212 has been described. On the other hand, in the second embodiment, a case will be described in which the shaping mask 212 is movable in the direction along the condensed optical axis.

  FIG. 5 is an enlarged view showing the processing head body 10 of the laser processing apparatus 1 according to the second embodiment of the present invention. As shown in FIG. 5, in addition to the configuration of the first embodiment, the mask moving mechanism unit 213 according to the second embodiment can move the shaping mask 212 in the direction along the converging optical axis. It further has an axial movement mechanism 213a. Note that the movement amount in the direction along the condensed optical axis is also controlled by the mask movement amount control unit 214. Other configurations are the same as those of the first embodiment.

  As described above, the second embodiment includes the axial movement mechanism 213a that can move the shaping mask 212 also in the direction along the condensed optical axis. Thereby, the distance of the shaping mask 212 with respect to the processing lens 200 (that is, corresponding to the relative position of the processing lens 200 and the shaping mask 212 in the light collecting optical axis direction) can be adjusted. As a result, the distance between the shaping mask 212 and the processed surface 2a of the workpiece 2 is also changed.

  As a result, when the distance between the shaping mask 212 and the processing surface 2a of the workpiece 2 is wider than the distance between the shaping mask 212 of the first embodiment and the processing surface 2a of the workpiece 2, the tapered hole 211 The position of the laser beam that is reflected and reaches the processing surface 2a is further shifted backward in the processing direction. As a result, the laser beam irradiated onto the processed surface 2a of the workpiece 2 can be expanded in a wider range.

  On the other hand, when the distance between the shaping mask 212 and the processed surface 2a of the workpiece 2 is narrower than the distance between the shaping mask 212 of the first embodiment and the processed surface 2a of the workpiece 2, the tapered hole 211 is provided. Therefore, the position of the laser beam reflected by the laser beam and reaching the processing surface 2a is shifted further forward in the processing direction. As a result, the laser beam irradiated onto the processing surface 2a of the workpiece 2 can be concentrated in a narrower range.

  As described above, according to the laser processing apparatus in the second embodiment, in addition to the configuration in the first embodiment, the shaping mask can be moved in the direction along the converging optical axis. Yes. By providing such a configuration, the distance between the shaping mask and the work surface of the workpiece can be adjusted. As a result, the irradiation shape of the laser beam can be expanded / contracted. Furthermore, since the expansion / contraction range of the irradiation shape of the laser light can be changed, the shape of the laser light can be changed to an optimum state according to the processing content of the workpiece. As a result, the processing speed can be further increased.

Embodiment 3 FIG.
In the first embodiment, the case where the position of the shaping mask 212 can be adjusted on a plane orthogonal to the light collection optical axis has been described. In the second embodiment, the case where the position of the shaping mask 212 can be further adjusted in the direction along the converging optical axis has been described. On the other hand, in the third embodiment, the case where the position of the shaping mask is fixed and the position of the processing lens 200 is variably controlled will be described.

  FIG. 6 is an enlarged view showing the processing head body 10 of the laser processing apparatus 1 according to the third embodiment of the present invention. As shown in FIG. 6, the shaping mask 212 is fixed in the processing head unit 20 by a fixing material (not shown). On the other hand, the processing lens 200 is provided with a lens movement mechanism unit 203 and a lens movement amount control unit (condenser movement amount control unit) 204 that controls the position of the lens movement mechanism unit 203.

  In the third embodiment, the lens moving mechanism unit 203 can move the processing lens 200 in a direction orthogonal to the condensing optical axis direction of the laser light (see the left and right arrows shown in FIG. 6). . In addition, it further includes an axial movement mechanism 203a that allows the processing lens to move in the direction along the converging optical axis.

  FIG. 7 is a top view of the lens moving mechanism unit 203 shown in FIG. As shown in FIG. 7, the lens moving mechanism unit 203 includes a plurality (four in this example) of piezoelectric elements 203b. The piezoelectric elements 203b are arranged at a distance from each other around the processing lens 200. In this example, the piezoelectric elements 203b are arranged at intervals of 90 degrees around the processing lens 200. Thereby, the processing lens 200 is movable on a plane orthogonal to the condensing optical axis.

  The lens moving mechanism 203 is provided with an axial moving mechanism 203a, similar to the axial moving mechanism 213a provided on the shaping mask 212 described in the second embodiment. Thereby, the processing lens 200 is movable also in the direction along the condensing optical axis. The lens movement mechanism unit 203 including the axial direction movement mechanism 213a and the piezoelectric element 203b is connected to the lens movement amount control unit 204 as in the second embodiment.

  The lens movement amount control unit 204 uses a state in which the condensing optical axis and the central axis of the processing lens coincide with each other as a reference to determine whether the condensing optical axis and the central axis of the processing lens 200 correspond to the processing content of the workpiece 2 Determine the amount of eccentricity. The amount of decentering is such that even if a part of the laser beam whose optical axis is shifted due to the center axis of the processing lens 200 being decentered from the converging optical axis hits the side surface 211a of the tapered hole and is reflected, the reflected laser beam is processed. It is determined within a range in which it can escape to the irradiation unit 30 side without returning to the lens 200 side.

  The lens movement amount control unit 204 can be appropriately changed even during processing so that the amount of eccentricity between the condensing optical axis and the center axis of the processing lens becomes an optimum state for processing the workpiece 2. Other configurations are the same as those of the first embodiment.

  As described above, in the third embodiment, instead of fixing the position of the shaping mask 212, the processing lens 200 is processed in a plane perpendicular to the converging optical axis and in a direction along the converging optical axis. The lens 200 can be moved. As a result, the condensed optical axis is decentered with respect to the central axis of the tapered hole 211, and the same effect as when the shaping mask 212 is moved can be obtained.

  FIG. 8 is a schematic diagram showing the injection of the processing gas when the optical axis is decentered by moving the processing lens 200 by the lens movement amount control unit 204 in the second embodiment of the present invention. As described in the first and second embodiments, the mask moving amount control unit 214 moves the shaping mask 212 as shown in FIG.

  In FIG. 8A, when the central axis of the tapered hole 211 coincides with the converging optical axis, the laser beam is irradiated from the central portion of the irradiation unit 30. At this time, the shape of the laser light applied to the workpiece 2 is substantially circular as shown in FIG. 4A of the first embodiment. Accordingly, the energy at the center of the circle is increased. Thereby, the workpiece | work 2 of the area | region ahead of a process direction rather than the center part of a laser beam is a state which is not processed. At this time, a part of the processing gas hits the workpiece 2 that has not been processed and is diffused forward in the processing direction. That is, since the processing gas diffused forward in the processing direction does not contribute to the processing, the processing gas is wasted.

  On the other hand, as shown in FIG. 8B, when the shaping unit 210 performs machining with the optical axis decentered forward in the machining direction, laser light is emitted from the front of the irradiation unit 30 in the machining direction. Thereby, the process of the workpiece | work 2 is started from the process direction front of the irradiation part 30. FIG. Therefore, the amount that the processing gas diffuses to the workpiece 2 that has not been processed can be reduced as compared with the case of FIG. 8A. In other words, the ratio of the processing gas that diffuses backward in the processing direction can be increased. it can. Thereby, the discharge | emission capability of a molten metal improves and it can also lead to the speeding-up of a process.

  As described above, the laser processing apparatus according to the third embodiment has a structure capable of adjusting the position of the processing lens. By providing this configuration, the condensing optical axis can be decentered with respect to the central axis of the tapered hole. As a result, it is possible to obtain the same effect as the case of adjusting the position of the shaping mask as described in the first and second embodiments.

  Further, since the laser beam can be brought closer to the front of the taper hole in the processing direction, waste of processing gas consumption can be reduced and the cost can be reduced. This effect can be obtained even when the position of the shaping mask as described in the first and second embodiments is adjusted.

  In the third embodiment, the shaping mask 212 is fixed. However, the position adjustment of the processing lens 200 and the position adjustment of the shaping mask 212 can be used in combination.

  In the third embodiment, the processing lens 200 can be moved on a plane perpendicular to the light collection optical axis by the lens moving mechanism 203. However, the moving method is not limited to this, and the processing is not limited to this. It is only necessary that the lens 200 be movable on a plane perpendicular to the light collection optical axis and in a direction along the light collection optical axis. For example, the processing lens 200 may be moved in the direction along the condensed optical axis by the lens movement control device used in the first embodiment.

  Further, in the third embodiment, the processing lens 200 is moved and decentered. However, by automating the alignment adjustment of the reflection mirror 4a of the transmission optical system 4, the optical axis of the laser light incident on the processing lens 200 is obtained. May be decentered.

Embodiment 4 FIG.
In the first to third embodiments, the case where the shaping mask 212 is provided in the processing head unit 20 has been described. On the other hand, in the fourth embodiment, a case where the shaping mask 212 is not provided in the processing head unit 20 but the shaping mask 212 is integrated with the irradiation unit 30 will be described.

  FIG. 9 is an enlarged view showing the processing head body 10 of the laser processing apparatus 1 according to the fourth embodiment of the present invention. FIG. 10 is an enlarged cross-sectional view showing the irradiation unit 30 of FIG. As shown in FIG. 9, the shaping mask 212 is not provided in the processing head unit 20. Instead, in the fourth embodiment, the shaping mask 212 is integrated with the irradiation unit 30 as shown in FIG. Therefore, a highly reflective material that reflects laser light is used for the irradiation unit 30.

  In addition, the irradiation unit 30 has a cylindrical shape having a tapered hole that continuously narrows from the processing lens 200 side toward the work 2 side in the direction along the condensing optical axis. Other configurations are the same as those of the third embodiment.

  When irradiating the irradiation unit 30 with high-intensity laser light, there is a concern that the irradiation unit 30 itself is processed. However, since the laser beam irradiated to the tapered hole side surface 211a inside the irradiation unit 30 is a skirt portion of the laser beam, the intensity is lowered and the irradiation unit 30 itself is not processed.

  As described above, according to the laser processing apparatus in the fourth embodiment, the injection unit and the shaping mask are integrated. By providing such a configuration, the trouble of separately manufacturing a shaping mask can be saved. As a result, the cost can be reduced and the processing head body can be reduced in weight.

  In each of the above embodiments, metal is used for the work 2, but is not limited thereto. For example, resin, ceramic, glass, or the like may be used.

  In each of the above embodiments, the shaping mask 212 is formed of a highly reflective material, but at least the tapered hole side surface 211a may be a highly reflective material. Therefore, the taper hole side surface 211a may be coated with a highly reflective material.

  Further, in each of the above-described embodiments, a condensing lens is used as the processing lens 200, but a reflective optical element such as a rectangular mirror may be used.

  In Embodiments 1 to 3, the shaping unit 210 is disposed between the processing lens 200 and the irradiation unit 30, but the shaping unit 210 is disposed between the laser light oscillator 3 and the processing lens 200. May be.

  Moreover, the mechanism part and control part which change the relative position of the shaping mask 212 and the process lens 200 should just be provided in at least any one of the shaping mask 212 and the process lens 200, and the combination is each said. The present invention is not limited to the embodiment.

  DESCRIPTION OF SYMBOLS 1 Laser processing apparatus, 2 Workpiece | work (board | substrate), 2a Processing surface, 3 Laser light oscillator, 4 Transmission optical system, 4a Reflection mirror, 5 Gas supply apparatus, 5a Gas cylinder, 5b Gas pipe, 10 Processing head main body, 20 Processing head part, 30 irradiation unit, 200 processing lens (condenser), 203 lens movement mechanism unit, 203a axial movement mechanism, 203b piezoelectric element, 204 lens movement amount control unit, 210 laser shape shaping unit, 211 taper hole, 211a side surface of taper hole , 212 Shaping mask, 213 Mask moving mechanism, 213a Axial moving mechanism, 214 Mask moving amount controller.

Claims (9)

A laser oscillator that emits laser light,
A condenser for condensing the laser beam toward a substrate to be processed;
A tapered hole is formed which is disposed between the light collector and the substrate and continuously narrows as it approaches the substrate in the direction along the optical axis of the laser light collected by the light collector, A shaping mask for shaping the irradiation shape on the substrate by reflecting a part of the laser beam condensed by the condenser on the side surface of the tapered hole and irradiating the substrate;
A part of the laser beam, which is provided on at least one of the light collector and the shaping mask and is condensed by the light collector, is reflected by the side surface of the tapered hole and irradiated onto the substrate. A mechanism part capable of changing a relative position between the light collector and the shaping mask so that the irradiation shape irradiated on the substrate has a desired intensity distribution; and the shaping mask A laser processing apparatus comprising: an irradiation unit configured to irradiate the substrate with the laser beam shaped by step (b). Irradiated on the substrate by changing the relative position according to the processing content of the substrate and changing the amount of laser light reflected on the side surface of the tapered hole and irradiated on the substrate. The laser processing apparatus according to claim 1, further comprising a movement amount control unit that performs position control of the mechanism unit so that the irradiation shape has a desired intensity distribution. The mechanism part is a mask moving mechanism part provided on the shaping mask and configured to be movable on a plane orthogonal to the optical axis of the laser beam condensed by the condenser. Yes,
The movement amount control unit controls the position of the mask movement mechanism unit so that the irradiation shape irradiated on the substrate has a shape having the desired intensity distribution, thereby removing the shaping mask. Move on a plane,
The laser processing apparatus according to claim 2. The mask moving mechanism unit further includes an axial direction moving mechanism that enables the shaping mask to be displaced in an axial direction that is a direction along the optical axis of the laser beam collected by the light collector,
The movement amount control unit controls the position of the mask movement mechanism unit so that the irradiation shape irradiated on the substrate has a shape having the desired intensity distribution, thereby removing the shaping mask. The laser processing apparatus according to claim 3, wherein the laser processing apparatus is moved on a plane and in the axial direction. The mechanism unit is a lens moving mechanism unit that is provided on the light collector and is movable on a plane orthogonal to the optical axis of the laser beam condensed by the light collector. Yes,
The movement amount control unit controls the position of the lens moving mechanism unit so that the irradiation shape irradiated on the substrate has a shape having the desired intensity distribution, thereby allowing the condenser to The laser processing apparatus according to any one of claims 1 to 4, wherein the laser beam is moved on a plane and the optical axis of the laser beam condensed by the condenser is shifted. The lens moving mechanism unit further includes an axial moving mechanism that enables the shaping mask to be displaced in an axial direction that is a direction along the optical axis of the laser light condensed by the condenser.
The movement amount control unit controls the position of the lens moving mechanism unit so that the irradiation shape irradiated on the substrate has a shape having the desired intensity distribution, thereby allowing the condenser to The laser processing apparatus according to claim 5, wherein the laser beam is moved in a plane and in the axial direction, and the optical axis of the laser beam condensed by the condenser is shifted. The laser processing apparatus according to any one of claims 1 to 6, wherein the shaping mask is integrated with the irradiation unit. The laser processing apparatus according to any one of claims 1 to 7, wherein the shaping mask has the tapered hole formed of a highly reflective material. A laser oscillator that emits laser light,
A condenser for condensing the laser beam toward a substrate to be processed;
A tapered hole is formed which is disposed between the light collector and the substrate and continuously narrows as it approaches the substrate in the direction along the optical axis of the laser light collected by the light collector, A shaping mask for shaping the irradiation shape on the substrate by reflecting a part of the laser beam condensed by the condenser on the side surface of the tapered hole and irradiating the substrate;
A mechanism that is provided on at least one of the light collector and the shaping mask, and that allows a relative position between the light collector and the shaping mask to be changed;
A laser processing method applied to a laser processing apparatus including an irradiation unit that irradiates the substrate with the laser light shaped by the shaping mask, and a movement amount control unit that performs position control of the mechanism unit,
In the movement amount control unit, the relative position is changed according to the processing content of the substrate, and the amount of laser light irradiated to the substrate by being reflected by the side surface of the tapered hole is changed to be irradiated onto the substrate. The laser processing method which has the step which performs the said position control of the said mechanism part so that the said irradiation shape may become a shape which has desired intensity distribution.

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