JP5546924B2 - Laser processing method and laser processing apparatus - Google Patents

Description

  The present invention relates to a laser processing method and a laser processing apparatus.

  A technique for forming grooves for forming lines (patterns) and pads on the surface of a substrate by laser light, so-called trench processing technique is known. FIG. 9 is a diagram illustrating a configuration of an optical system of a laser processing apparatus that performs trench processing.

  In the figure, a laser beam 5 emitted from a laser oscillation source 1 is shaped by passing through a window 10a formed in an aperture 10 disposed on the optical axis of the laser beam 5, and a galvanometer mirror 23, 24 is incident. The laser beam 5 incident on the galvanometer mirrors 23 and 24 is deflected in two horizontal axes by the mirrors 23 and 24, is incident on the Fθ lens 25, is condensed by the Fθ lens 25, and is incident on the workpiece 28 on the table. To do. The size of the processing region 26 on the workpiece 28 is determined by the size of the Fθ lens 25, and the laser light 5 is positioned at an arbitrary position in the processing region 26 by positioning the galvanometer mirrors 23 and 24 in the rotation direction. Can do.

  FIG. 10 is a diagram for explaining a connecting portion between the line groove L and the pad groove P (hereinafter, the line groove is referred to as “line groove” and the pad groove is referred to as “pad groove”). FIG. 4A shows a case where the tip of the laser beam 5 for processing the line groove L is a part of an arc, and FIG. 4B shows a case where the tip of the laser beam 5 for processing the line groove L is a straight line. The upper stage is a plan view, and the lower stage is a sectional view taken along line AA and BB in the plan view.

  The line groove L and the pad groove P cannot be processed simultaneously. For this reason, in the process overlap part 9 and 38 where a process area | region overlaps, after processing by one side, it processes by the other side further. As a result, the processing depth of the processing overlapping portions 9 and 38 becomes deeper than other portions. Since the pad groove P is circular, the shape of the window 10a of the aperture 10 when the pad groove P is processed is a circle. Also, the window 10a when processing the line groove L is often a circle. Hereinafter, the shape of the window 10a of the aperture 10 is simply referred to as “window 10a”.

  As shown in FIGS. 10 (a) and 10 (b), when the machining overlap portions 9 and 38 are generated, the reliability of the workpiece may be lowered. Therefore, for example, in Patent Document 1, by providing a filter that covers a part of the window 10a, a laser beam 5 having an energy distribution whose circular center part can process a workpiece and a ring-shaped outer peripheral part that cannot be processed is formed. And the technique which irradiated a ring-shaped outer peripheral part to a process overlap part is disclosed.

JP-A-64-75191

  However, even with the technique described in Patent Document 1, the ring-shaped outer peripheral portion cannot be processed without overlapping processing. For this reason, it is impossible to prevent the grooves from being excessively processed in the overlapped portion and deepening the groove.

  Therefore, the problem to be solved by the present invention is to make the depth of the line groove and the pad groove uniform in all the processing regions.

The first means for solving the above-described problem is to process the line groove by the first scanning of the laser beam, and process the pad groove by the second scanning of the laser beam to form the line groove and the pad groove. In the laser processing method for connection, the processing region of the pad groove is divided into a first processing region and a second processing region in contact with the first region, and the first processing is performed by the first scanning. The second processed region is processed by the second scan, and the line groove processed by the first scan and the region processed by the second scan are within the pad groove . In the present invention, they are in contact with each other.

The second means processes the line groove by the first scanning of the laser beam, processes the circular pad groove by the second scanning of the laser beam, and connects the line groove and the pad groove. in the the first scan, until the width matches the chord of the pad, processing the line groove, the through second scanning, the pad excluding the processing region by the first scan A region in the groove is processed, and the line groove processed by the first scan and the region processed by the second scan are in contact with each other in the pad groove .

A third means is a laser processing method of processing a line groove by a first scan of laser light, processing a circular pad groove by a second scan of laser light, and connecting the line groove and the pad groove. In step 2, the region in the pad groove is processed by the second scan, and the tip portion is formed in a concave shape equal to the curvature of the pad groove until the tip portion comes into contact with the outer periphery of the pad. The line groove is processed, and the line groove processed by the first scanning and the region processed by the second scanning are in contact with each other on the outer periphery of the pad.

The fourth means is a laser processing apparatus for shaping the outer shape of the laser beam by a window provided in the aperture, condensing the laser beam by a condenser lens and irradiating the workpiece, and the adjacent region of the pad groove and the line groove is in contact with each other, and the outer edge shape of the window for shaping the outer shape of the laser beam for forming the pad grooves, and said pad groove side of the distal end shape of the window for shaping the outer shape of the laser beam for forming the line groove Characterized by matching.

  A fifth means is characterized in that, in the fourth means, the pad groove side of the adjacent region is formed in a concave shape and the line groove side is formed in a convex shape, and the outer width of the line groove coincides with the chord of the pad groove. And

  Sixth means is that in the fourth means, the pad groove side of the adjacent region is formed in a straight line and the line groove side is formed in a straight line, and the outer width of the line groove coincides with the chord of the pad groove. Features.

Seventh means, in the fourth means, the pad groove side of the adjacent region is formed in a shape that line groove side arc of the outer peripheral portion in contact with the outer periphery of the circular arc, chord of the outer width of the pad grooves of the line groove The shape of the window is set to a shape that coincides with.

  According to an eighth means, in any one of the fourth to seventh means, the outer edge shape of the window is provided on a circular window and the outer edge of the window, and a plurality of the window can be advanced and retracted in the diameter direction of the window. It is set by a protrusion part, It is characterized by the above-mentioned.

  In the embodiment described later, the laser beam is denoted by reference numeral 5, the line groove is denoted by reference numeral L, the pad groove is denoted by reference numeral P, and the first processing region is formed in a portion indicated by the pad groove in FIG. 4 is a portion of the connecting portion between the pad groove and the line groove in FIG. 4 that has digged into the pad groove side of the line groove, the aperture is indicated by reference numerals 10, 50, and the windows are indicated by reference numerals 10a1-9, 10b1-16, 10c. 10 c 1 to 6, the condenser lens corresponds to the Fθ lens 25, the workpiece corresponds to 28, and the protrusion corresponds to the mask 62.

  According to the present invention, since there is no overlapped portion of processing, the depth of the line groove and the pad groove can be made uniform in all the processing regions.

It is a block diagram of the optical system of the laser processing apparatus which concerns on this invention. It is a front view of the aperture which concerns on this invention. It is a top view of the process part by this invention. It is a figure which shows the example of a combination of the window for line grooves, and the window for pad grooves. It is a figure which shows the example of a process in case two lines are connected to a pad. It is a figure which shows the modification of an aperture. It is a front view of the aperture which concerns on this invention. It is a front view of the other aperture which concerns on this invention. It is a block diagram of the optical system of the laser processing apparatus which performs trench processing. It is a figure explaining the connection part of the groove | channel L for the conventional lines, and the groove | channel P for pads.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of an optical system of the laser processing apparatus according to the first embodiment, and FIG. 2 is a front view of the aperture. In addition, the same reference numerals are given to the same parts as those in the conventional example shown in FIG.

  As shown in the figure, the laser processing apparatus according to the first embodiment is the same as the conventional laser processing apparatus except that the configuration of the aperture is different.

  In other words, the first to ninth windows 10a1 to 10a9 are formed in the aperture 50 according to the first embodiment. The first 10a1 has a crescent shape in which a part of a circle with a diameter d indicated by a dotted line is cut out from a circle with a diameter D. The length of the chord in the portion where the outer shape is cut out is d. The second to eighth windows 10a2 to 10a8 are obtained by rotating the first window 10a1 around the center O by 45 degrees. The ninth window 10a9 is a circle having a diameter d. The aperture 50 is installed in a linear guide device (not shown), and is moved and positioned by a driving means (not shown) in a direction perpendicular to the optical axis of the laser beam 5.

  FIG. 3 is a plan view of the processing portion. In the figure, the processing when the diameter of the pad groove P is kD and the width of the line groove L is kd is executed in the following procedure. In the example of FIG. 3, the line groove L is connected vertically upward to the pad groove P.

  First, the center O of the ninth window 10 a 9 is positioned on the optical axis of the laser beam 5. The laser beam 5 that has passed through the ninth window 10a9 is shaped into a circle having a diameter d and then reduced to a circle having a diameter kd by the Fθ lens 25. Note that k is a proportional constant. Similarly to the conventional method, the line groove L having a width kd is processed using the laser beam 5 having a diameter kd (first scanning of the laser beam). When the line groove L intersects the pad groove P, the processing is finished at a point where the chord length of the pad groove P is kd. As a result, a region surrounded by the arc (the chord length is kd) of the pad groove P intersecting the line groove L and the semicircular portion at the tip of the line groove L indicated by a two-dot chain line in FIG. It is processed as a line groove L.

  Next, after the center O of the fifth window 10a5 is positioned on the optical axis of the laser beam 5, the laser beam 5 is oscillated. The laser beam 5 is shaped into a crescent shape having an outer diameter D by the fifth window 10a5, and the outer diameter is reduced to kD by the Fθ lens 25, and the line groove L is not processed, and is hatched in FIG. The crescent-shaped portion shown is processed (second scan of laser light). As a result, the pad groove P is processed to a uniform depth without generating a processing overlap portion.

  FIG. 4 is a diagram showing a combination example of a window for a line groove and a window for a pad groove. FIG. 4A shows the above combination, and FIG. 4B and FIG. FIG. 4D is a modification of FIG.

  FIG. 5B is a processing example in which the tip of the laser beam 5 for processing the line groove L is straightened by the half-moon shaped window 11a, and a straight portion is provided in the window 11b for processing the pad groove P. The straight line corresponds to the string. In FIG. 6C, the tip of the laser beam 5 for processing the line groove L is formed into a concave arc having a curvature equal to the curvature of the window 12b for processing the pad groove P by the window 12a, and the window 12b for processing the pad groove P is formed. This is an example of processing in a circle. Further, FIG. 4D shows the line groove L that is made to enter the pad groove P by a length a as compared with the case of FIG.

  When the window of the aperture 50 is formed in FIG. 2B, a window 11b group in which straight chords as shown by a one-dot chain line in FIG. 2 are formed, and when the window of the aperture 50 is formed in FIG. 2 can be configured as a circular window (circle having the same diameter as that of the first window 10a1) indicated by a one-dot chain line outside the ninth window 10a9. Further, in the same figure (d), the window in which the line groove L is entered into the pad groove P by the length a as compared with the case of (a) corresponds to the first to ninth windows in FIG. What is necessary is just to form.

In any case, as shown in FIG. 4, the window shape of each aperture for the pad groove and the line groove forms a line with the outer edge shape of the window for shaping the outer shape of the laser beam forming the pad groove. The tip of the window for shaping the outer shape of the laser beam coincides with the tip shape on the pad groove side, and the pad groove and the adjacent region of the line groove are in contact with each other. At that time, in FIG. 4A, the pad groove side of the adjacent region is formed in a concave shape and the line groove side is formed in a convex shape, and the outer width of the line groove is made to coincide with the chord of the pad groove. In FIG. 4C, the pad groove side of the adjacent region is formed linearly and the line groove side is also formed linearly, and the outer width of the line groove coincides with the chord of the pad groove. The pad groove side is formed in a curvature shape in contact with the outer periphery of the arc, and the line groove side is in contact with the outer periphery of the arc, and the outer width of the line groove is matched with the chord of the pad groove. Further, in FIG. 4D, the line groove is further advanced to the pad groove side from the relationship of FIG. 4A, and the outer width of the line groove is matched with the chord of the pad groove.

  FIG. 5 is a diagram showing a processing example when two lines are linearly connected to the pad. When two lines are connected to one pad, as shown in the figure, a window is formed so that the line groove L and the pad groove are in contact at two opposite positions. In the case of the connection configuration shown in FIG. 5 (a), the shape of the pad groove window shown in FIG. 4 (a) is circularly cut out at two locations where the line groove window shape is linearly opposed. In the case of the connection configuration shown in FIG. 5 (b), the pad groove window shown in FIG. 4 (b) is arced at two points where the line groove window shape is linearly opposed. Set to a shape that is notched in a straight line.

  In the example of FIG. 2, the aperture 50 is formed of a rectangular plate material, and the first to ninth windows 10a1 to 10a9 are formed in the plate material. However, as shown in FIG. 4A, a plurality of pad groove windows 10b1 to 10b16 as shown in FIG. 4 (a), 16 in this case, are drilled and arranged, and the aperture 51 is clockwise or counterclockwise with respect to the center thereof. The center of the desired window can be positioned on the optical axis of the laser beam 5 for processing. The windows 10b1 to 10b16 can be used instead of those illustrated in FIGS. 4B to 4D in addition to those illustrated in FIG.

  The second embodiment is intended to diversify the shape of the aperture.

  FIG. 7 is a front view of an aperture according to the second embodiment, and the optical system of the laser processing apparatus is the same as that of the first embodiment shown in FIG. 1 except for the aperture portion. In addition, the same reference numerals are given to the same parts as those in the conventional example shown in FIG.

  In FIG. 7, a plurality (eight in the illustrated example) of mask forming mechanisms 61 are arranged on the outer periphery of a circular window 10 at equal intervals on the circumference. Each of the mask forming mechanisms 61 includes a mask 62 and an actuator 64 such as a motor or a cylinder that moves the mask 62 back and forth toward the center O of the window 10. The tip of the mask 62 is semicircular, and can enter the inside of the window 10c from a position that does not overlap the window 10c to a specified distance, for example, a position indicated by a dotted line in the drawing. Then, any of the masks 62 is allowed to enter the window 10c, whereby windows equivalent to the windows 10a1 to 10a9 shown in FIG. 2 can be formed. Therefore, it is not necessary to provide a large number of windows in the aperture. In the case shown in the figure, when two adjacent masks 62 enter the window 10c, they interfere with each other. However, since the line grooves L are not arranged in this manner, such interference does not occur in practice.

  Since the processing procedure is substantially the same as that of the first embodiment, description thereof is omitted.

  Although not shown in the drawings, if the tip of the mask 62 is replaced with the pad groove aperture shown in FIGS. 4B to 4D, the pad groove shown in FIGS. It is possible to form a window equivalent to the window for use, and in this case also, since there is no overlapping portion, the groove depth becomes uniform.

  FIG. 8 is an example corresponding to the diversity of windows and masks. In this example, the center of the movement locus of the mask 62 of the mask forming mechanism 61 shown in FIG. 7 is positioned on the optical axis of the laser beam 5, and the windows 10c1 and 10c2 having different diameters drilled in the aperture 10 at the position. , 10c3, 10c4, 10c5, 10c6 can be selected and processed. Thus, a window may be selected based on the size of the pad groove L, the center of the window may be positioned on the optical axis of the laser beam 5, and the mask 62 may be advanced by a desired distance.

  Also in this case, the combination of the shape of the line groove L and the pad groove P as shown in FIG. 4 makes it possible to prevent the processing overlapping portion from occurring, and the groove depth becomes uniform.

  Further, if the aperture 10 is replaced with the annular plate shown in FIG. 6 and the windows 10b1 to 16b are arranged in circles having different diameters, the center of the window is aligned with the optical axis of the laser beam 5 as shown in FIG. By rotating the annular plate member, it is possible to select circular openings having different diameters. Accordingly, a desired combination of the line groove L and the pad groove P can be realized by driving the mask forming mechanism 61 through the opening.

  In the above description, the pad groove P is processed after the line groove L is processed. However, even if the line groove L is processed after the pad groove P is processed, overlapping portions are formed. The same processing result can be obtained because it is not performed.

DESCRIPTION OF SYMBOLS 1 Laser oscillation source 5 Laser beam 10,50 Aperture 10a1-9, 10b1-16, 10c, 10c1-6 Window Galvanometer mirror 23,24
25 Fθ lens 28 Work 62 Mask L Line groove P Pad groove

Claims (8)

In a laser processing method of processing a line groove by a first scan of laser light, processing a pad groove by a second scan of laser light, and connecting the line groove and the pad groove,
Dividing the processing region of the pad groove into a first processing region and a second processing region in contact with the first region;
Processing the first processing region by the first scanning and processing the second processing region by the second scanning;
A laser processing method, wherein the line groove processed by the first scanning and the region processed by the second scanning are in contact with each other in the pad groove . In a laser processing method of processing a line groove by a first scan of laser light, processing a circular pad groove by a second scan of laser light, and connecting the line groove and the pad groove,
By the first scanning, the line groove is processed until the width matches the chord of the pad groove ,
Wherein the second scanning, and processing the area in the pad grooves excluding the processing region by the first scan,
A laser processing method, wherein the line groove processed by the first scanning and the region processed by the second scanning are in contact with each other in the pad groove . In a laser processing method of processing a line groove by a first scan of laser light, processing a circular pad groove by a second scan of laser light, and connecting the line groove and the pad groove,
Processing the region in the pad groove by the second scanning,
By the first scan the tip was recessed equal to the curvature of the pad grooves, processing the line groove to the tip in contact with the outer periphery of the pad grooves,
A laser processing method, wherein the line groove processed by the first scanning and the region processed by the second scanning are in contact with each other on an outer periphery of the pad groove . In the laser processing apparatus that shapes the outer shape of the laser beam by the window provided in the aperture, condenses the laser beam by the condenser lens, and irradiates the workpiece,
As flanking regions of the pad grooves and line groove are in contact with each other, and the outer edge shape of the window for shaping the outer shape of the laser beam for forming the pad groove, said window shaping the outer shape of the laser beam for forming the line groove laser processing apparatus is characterized in that is matched with the said pad groove side of the tip shape. The laser processing apparatus according to claim 4,
The laser processing apparatus according to claim 1, wherein the pad groove side of the adjacent region is concave and the line groove side is convex, and the outer width of the line groove coincides with the chord of the pad groove. The laser processing apparatus according to claim 4,
The laser processing apparatus according to claim 1, wherein the pad groove side of the adjacent region is formed in a straight line and the line groove side is formed in a straight line, and an outer width of the line groove coincides with a chord of the pad groove. The laser processing apparatus according to claim 4,
The pad groove side of the adjacent region is formed in a shape that line groove side arc of the outer peripheral portion in contact with the outer periphery of the circular arc, the shape of the window is set to shape the outer width of the line groove coincides with the chord of the pad grooves The laser processing apparatus characterized by the above-mentioned. The laser processing apparatus according to any one of claims 4 to 7,
An outer edge shape of the window is set by a circular window and a plurality of protrusions that are provided on the outer edge of the window and can be advanced and retracted in the diameter direction of the window .

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