JP2020182960A - Laser processing device - Google Patents

Abstract

To enable a width of a split groove to be easily changed in subjecting a wafer to ablation processing.SOLUTION: Control means 51 changes positions of a first plate 63 and a second plate 64 to appropriately set a slit width of a slit S. The control means 51 controls the positions of the first plate 63 and the second plate 64 according to a value of the slit width so that a center of the slit S is matched with a center of an optic axis of laser light L. This can appropriately maintain a shape of a split groove even if changing the slit width of the slit S, namely a width of the split groove. Therefore, the width of the split groove can be changed easily and freely in subjecting a wafer to ablation processing.SELECTED DRAWING: Figure 2

Description

The present invention relates to a laser processing apparatus.

There is a laser processing apparatus that ablates a wafer to form a dividing groove by irradiating the wafer with a laser beam. Chips are obtained by splitting the wafer along the split groove. In such a laser processing apparatus, the width of the dividing groove is narrowed in order to produce a large number of chips.

For example, in the technique disclosed in Patent Document 1, a laser beam having a narrowed width passing through the slit is irradiated using a gap (slit) at a predetermined interval to narrow the width of the dividing groove.
That is, in the technique of this document, the slit has a width corresponding to the dividing groove, and this width is narrowed. By irradiating the wafer with a laser beam that has passed through such a narrow slit, a narrow split groove is formed.

JP-A-2010-158710

However, conventionally, with respect to the width of the slit, a plate (mask member) in which a slit having a predetermined width is formed has been used. Therefore, when changing the width of the slit, it is necessary to replace the plate, and after replacing the plate, it is necessary to adjust the position of the slit in order to match the center of the width of the slit with the center of the optical axis of the laser beam. , It is difficult to change the width of the slit.

As described above, conventionally, changing the width of the slit to change the width of the dividing groove reduces the productivity of the laser processing apparatus.

An object of the present invention is to easily change the width of the dividing groove when the wafer is ablated.
Another object of the present invention is to form a slit by aligning the center of the slit with the center of the optical axis of the laser beam.

The laser processing apparatus (the present processing apparatus) of the present invention includes a chuck table for holding a workpiece, a laser processing means for processing the workpiece held on the chuck table by irradiation with a laser beam, and the chuck table. A machining feed means that feeds the laser processing means in the X-axis direction and an index that feeds the chuck table in the Y-axis direction that is relatively orthogonal to the laser machining means in the X-axis direction. A laser processing apparatus including a feeding means, wherein the laser processing means includes a laser oscillator that oscillates a laser beam, a condenser that collects a laser beam oscillated from the laser oscillator, the laser oscillator, and the laser processing means. It is provided with an energy distribution correcting means for correcting the energy distribution in the W-axis direction, which is a direction perpendicular to the traveling direction of the laser beam, to a Gaussian distribution having a vertical base portion, which is arranged between the condenser and the energy. The distribution correcting means includes a first plate that shields one side of the laser beam in the W-axis direction, a second plate that faces the first plate and shields the other side of the laser beam in the W-axis direction, and the first plate. It is provided with a first moving mechanism for moving in the W-axis direction, a second moving mechanism for moving the second plate in the W-axis direction, and a control means for controlling the first moving mechanism and the second moving mechanism. The control means controls the first moving mechanism and the second moving mechanism to form a slit having a predetermined slit width in which the center and the center of the optical axis of the laser beam are aligned with the first plate and the second. It is configured to form with a plate.

Further, in the present processing apparatus, the control means includes a first storage unit that stores a standard energy amount, which is an energy amount measured by a power meter, of the first plate and a laser beam that is not shielded by the second plate. Measured by the power meter when either one of the first plate or the second plate is moved in the first direction approaching the other plate fixed in an open position that does not block the laser beam. The second storage unit that stores the intermediate position, which is the position of the one plate when the energy amount of the laser beam becomes half of the standard energy amount, and the one plate at the intermediate position are open. A third storage unit that stores the contact distance, which is the moving distance along the first direction until contact with the other plate at the position, and the one plate that is moved in the first direction. In a state of being in contact with the other plate in the open position, the first plate is placed in the opposite direction of the first direction so that the distance between the first plate and the second plate is the slit width. A first control unit that forms a slit having the slit width by moving in two directions,
In order to align the center of the slit formed by the first control unit with the center of the optical axis of the laser beam, the first plate and the second plate forming the slit are moved in the second direction. A second control unit that moves by (corresponding contact distance-the slit width / 2) may be provided.

Further, in the present processing apparatus, the control means includes a first storage unit that stores a standard energy amount, which is an energy amount measured by a power meter, of the first plate and a laser beam that is not shielded by the second plate. Measured by the power meter when either one of the first plate or the second plate is moved in the first direction approaching the other plate fixed in an open position that does not block the laser beam. A second storage unit that stores an intermediate position that is the position of one of the plates so that the amount of energy of the laser beam is half of the standard amount of energy, and a state in which the one plate is in the intermediate position. A third control unit that moves the other plate in the second direction opposite to the first direction and makes contact with the one plate, and the first plate and the second plate that are contacted by the third control unit. By moving the plates by half the distance of the slit width, one plate in the second direction and the other plate in the first direction, and separated from each other, they coincide with the center of the optical axis of the laser beam. A fourth control unit that has a center and forms a slit having the slit width may be provided.

In this processing apparatus, the control means appropriately sets the slit width by changing the positions of the first plate and the second plate, and makes the center of the slit coincide with the center of the optical axis of the laser beam. As a result, in this processing apparatus, even if the slit width, that is, the width of the dividing groove formed on the workpiece by the laser beam is changed, the center of the slit and the center of the optical axis of the laser beam are aligned with each other to form the dividing groove. The shape can be maintained properly. Therefore, when the work piece is ablated, the width of the dividing groove can be easily and freely changed.

Further, since the shape of the dividing groove can be appropriately maintained even if the width of the dividing groove is changed, the depth of the dividing groove can be made uniform. Therefore, it is possible to suppress the division failure of the workpiece.

It is a perspective view which shows the structure of the laser processing apparatus. It is explanatory drawing which shows the structure of the energy distribution correction means. It is explanatory drawing which shows the measurement state of the standard energy. It is explanatory drawing which shows the state which shielded the laser beam by the 1st plate. It is explanatory drawing which shows the state in which the 1st plate and the 2nd plate are in contact with each other. It is explanatory drawing which shows the state which made the width of the slit formed by the 1st plate and 2nd plate a predetermined slit width. It is explanatory drawing which shows the state which the center of the said slit coincides with the center of the optical axis of a laser beam. It is explanatory drawing which shows the other structure of the energy distribution correction means. It is explanatory drawing which shows the measurement state of the standard energy. It is explanatory drawing which shows the state which shielded the laser beam by the 1st plate. It is explanatory drawing which shows the state in which the 1st plate and the 2nd plate are in contact with each other. It is explanatory drawing which shows the state which made the width of the slit formed by the 1st plate and 2nd plate a predetermined slit width, and made the center of the slit coincide with the center of the optical axis of a laser beam.

[Embodiment 1]
The laser processing apparatus 10 shown in FIG. 1 forms a dividing groove in the wafer 1 by ablation processing with a laser beam.
The laser processing device 10 includes a rectangular parallelepiped base 11, a vertical wall portion 13 erected at one end of the base 11, and a control means 51 for controlling each member of the laser processing device 10.

A chuck table moving mechanism 14 for moving the chuck table 43 is provided on the upper surface of the base 11. The chuck table moving mechanism 14 processes and feeds the chuck table 43 in the X-axis direction and index feeds in the Y-axis direction orthogonal to the X-axis direction.

The chuck table moving mechanism 14 includes a chuck table portion 40 provided with a chuck table 43, an index feeding means 20 for moving the chuck table 43 in the index feeding direction, and a machining feeding means 30 for moving the chuck table 43 in the machining feed direction. I have.

The index feeding means 20 indexes the chuck table 43 in the Y-axis direction relative to the laser processing means 12.
The index feeding means 20 includes a pair of guide rails 23 extending in the Y-axis direction, a Y-axis table 24 mounted on the guide rails 23, a ball screw 25 extending parallel to the guide rail 23, and a drive motor 26 for rotating the ball screw 25. Includes.

The pair of guide rails 23 are arranged on the upper surface of the base 11 in parallel with the Y-axis direction. The Y-axis table 24 is slidably installed on the pair of guide rails 23 along the guide rails 23. The machining feed means 30 and the chuck table portion 40 are placed on the Y-axis table 24.

The ball screw 25 is screwed into a nut portion (not shown) provided on the lower surface side of the Y-axis table 24. The drive motor 26 is connected to one end of the ball screw 25 and rotationally drives the ball screw 25. When the ball screw 25 is rotationally driven, the Y-axis table 24, the machining feed means 30, and the chuck table portion 40 move in the index feed direction (Y-axis direction) along the guide rail 23.

The machining feed means 30 processes and feeds the chuck table 43 in the X-axis direction relative to the laser machining means 12.
The machining feed means 30 includes a pair of guide rails 31 extending in the X-axis direction, an X-axis table 32 mounted on the guide rail 31, a ball screw 33 extending parallel to the guide rail 31, and a drive motor for rotating the ball screw 33. It has 35.

The pair of guide rails 31 are arranged on the upper surface of the Y-axis table 24 in parallel with the X-axis direction. The X-axis table 32 is slidably installed on the pair of guide rails 31 along the guide rails 31. A chuck table portion 40 and a power meter 80 are placed on the X-axis table 32.

The ball screw 33 is screwed into a nut portion (not shown) provided on the lower surface side of the X-axis table 32. The drive motor 35 is connected to one end of the ball screw 33 and rotationally drives the ball screw 33. When the ball screw 33 is rotationally driven, the X-axis table 32 and the chuck table portion 40 move along the guide rail 31 in the machining feed direction (X-axis direction).

The chuck table portion 40 is used to hold the wafer 1 as an example of the workpiece. As shown in FIG. 1, the wafer 1 is held by the chuck table portion 40 as a work set WS including a ring frame F, an adhesive tape T, and a wafer 1.

The chuck table portion 40 has a chuck table 43 for holding the wafer 1, a clamp portion 45 provided around the chuck table 43, and a θ table 47 for supporting the chuck table 43. The θ table 47 is rotatably provided on the upper surface of the X-axis table 32 in the XY plane. The chuck table 43 is a member for sucking and holding the wafer 1. The chuck table 43 is formed in a disk shape and is provided on the θ table 47.

A holding surface containing a porous ceramic material is formed on the upper surface of the chuck table 43. This holding surface is communicated with a suction source (not shown). Four clamp portions 45 including a support arm are provided around the chuck table 43. The four clamp portions 45 are driven by an air actuator (not shown) to clamp and fix the ring frame F around the wafer 1 held on the chuck table 43 from all sides.

The vertical wall portion 13 of the laser processing device 10 is erected behind the chuck table moving mechanism 14. A laser processing means 12 is provided on the front surface of the vertical wall portion 13.

The laser processing means 12 processes the wafer 1 held on the chuck table 43 by irradiating the wafer 1 with a laser beam. In the present embodiment, the laser processing means 12 forms a dividing groove in the wafer 1 by ablating the wafer 1 with a laser beam.
The laser processing means 12 has a processing head 18 that irradiates the wafer 1 with a laser beam, and an arm portion 17 that supports the processing head 18.

The arm portion 17 projects from the standing wall portion 13 in the direction of the chuck table moving mechanism 14. The processing head 18 is supported by the tip of the arm portion 17 so as to face the chuck table 43 or the power meter 80 of the chuck table portion 40 in the chuck table moving mechanism 14.

The optical system of the laser processing means 12 is provided inside the arm portion 17 and the processing head 18.

As shown in FIG. 2, the laser processing means 12 includes a laser oscillator 61 that oscillates the laser beam L and an energy distribution corrector 62 that corrects the energy distribution of the laser beam L in the arm portion 17.

Further, the laser processing means 12 has a reflection mirror 65 that reflects the laser beam L and a condensing lens (condenser) 66 that condenses and outputs the laser beam L in the processing head 18.

The laser oscillator 61 is, for example, a solid-state laser light source. The laser oscillator 61 oscillates a laser beam in the −Y direction in the arm portion 17. The energy distribution of the laser beam L can be approximated by the Gaussian distribution. Therefore, the energy of the laser beam L has a distribution as shown by arrow A in the cross section in the W-axis direction.

Here, the W-axis direction is orthogonal to the traveling direction of the laser beam L and is orthogonal to the X-axis direction (direction perpendicular to the paper surface of FIG. 2) which is the processing feed direction. Therefore, the W-axis direction coincides with the Z-axis direction in the arm portion 17, and coincides with the Y-axis direction in the processing head 18.

The energy distribution corrector 62 is configured to be able to block a part of the laser beam L, and contributes to the correction of the energy distribution in the W-axis direction in the laser beam L.

The laser beam L that has passed through the energy distribution corrector 62 is reflected in the −Z direction by the reflection mirror 65 in the processing head 18 and guided to the condenser lens 66. The condensing lens 66 condenses the laser beam L and irradiates it toward the outside of the processing head 18 in the −Z direction.

The laser beam L focused by the condenser lens 66 irradiates the wafer 1 on the chuck table 43 when the wafer 1 shown in FIG. 1 is processed.
On the other hand, when the energy distribution in the laser beam L is corrected, the laser beam L irradiates the power meter 80 as shown in FIG.

The energy distribution correction means in the laser processing apparatus 10 will be described below. The energy distribution correcting means corrects the energy distribution in the W-axis direction of the laser beam L to a Gaussian distribution having a vertical base portion as shown by an arrow B. As a result, the width (length in the W-axis direction) of the laser beam L is set.

The energy distribution correcting means in the laser machining apparatus 10 includes the control means 51 and the power meter 80 shown in FIG. 2 in addition to the optical system of the laser machining means 12 built in the arm portion 17 and the machining head 18 described above.

As shown in FIG. 2, the energy distribution corrector 62 of the laser processing means 12 includes a first plate 63 arranged on the + W side of the laser beam L. Further, the energy distribution corrector 62 includes a second plate 64 arranged on the −W side of the laser beam L so as to face the first plate 63.
Further, the energy distribution corrector 62 includes a first moving mechanism 631 that moves the first plate 63 in the W-axis direction, and a second moving mechanism 641 that moves the second plate 64 in the W-axis direction.

Then, in the present embodiment, the first plate (upper blade) 63 is moved by the first moving mechanism 631 in the W1 direction (direction from the + W side to the −W side) as the first direction shown in FIG. This makes it possible to block one side (+ W side) of the laser beam L in the W-axis direction.

On the other hand, the second plate (lower blade) 64 is moved in the W2 direction (direction from the −W side to the + W side) as the second direction shown in FIG. 2 by the second moving mechanism 641, so that the laser beam L It is possible to block light from the other side (−W side) in the W-axis direction.

Further, the energy distribution corrector 62 includes a W-axis direction moving means 67 for moving the first plate 63 and the second plate 64 together along the W-axis direction. That is, the W-axis direction moving means 67 simultaneously moves the first plate 63 and the second plate 64 in the same direction and by the same distance along the W-axis direction.

The power meter 80 is arranged downstream of the condenser lens 66 in the traveling direction of the laser beam L. The power meter 80 is irradiated with the laser beam L focused by the condenser lens 66. As a result, the power meter 80 measures the amount of energy of the irradiated laser beam L.

The control means 51 controls each member of the laser machining apparatus 10 to perform machining on the wafer 1.

Further, the control means 51 controls the first moving mechanism 631, the second moving mechanism 641 and the W-axis direction moving means 67 shown in FIG. 2, and the width and shape of the cutting groove formed in the wafer 1 by ablation processing. The energy distribution of the laser beam L is corrected in order to adjust.

That is, the control means 51 controls the first moving mechanism 631, the second moving mechanism 641, and the W-axis direction moving means 67, and the slit through which the laser beam L is transmitted between the first plate 63 and the second plate 64. Form S.
The laser beam L passing through the slit S is focused by the condenser lens 66 and irradiated to the outside. The width (length in the W-axis direction) of the laser beam L irradiated to the outside becomes a value corresponding to the width of the slit S. Further, the width of the laser beam L corresponds to the width of the dividing groove formed in the wafer 1.

Therefore, in the energy distribution correction according to the present embodiment, the control means 51 moves the first moving mechanism 631, the second moving mechanism 641, and the W-axis direction so that the width of the slit S becomes an appropriate width desired by the operator. Control means 67.

Further, the control means 51 controls the first moving mechanism 631, the second moving mechanism 641, and the W-axis direction moving means 67 so that the center of the slit S (the center of the width) coincides with the center of the optical axis of the laser beam L. To do.
When the center of the slit S coincides with the center of the optical axis of the laser beam L in this way, the energy distribution of the laser beam L transmitted through the slit S becomes an appropriate Gaussian distribution having a vertical base portion. As a result, the shape of the cutting groove formed on the wafer 1 can be made into a desired shape.

The operation of energy distribution correction by the energy distribution correction means will be described below.
As shown in FIG. 3, in the energy distribution correction, the control means 51 first interposes between the first plate 63 and the second plate 64 so that the laser beam L is not shielded by the first plate 63 and the second plate 64. Open wide. Further, the control means 51 controls the chuck table moving mechanism 14 to arrange the power meter 80 directly under the condenser lens 66 in the processing head 18.

After that, the control means 51 controls the laser oscillator 61 to oscillate the laser beam L. The oscillated laser beam L is applied to the power meter 80 via the energy distribution corrector 62, the reflection mirror 65, and the condenser lens 66 shown in FIG. The power meter 80 measures the amount of energy of the laser beam L and transmits it to the control means 51.
In FIG. 3 and the like, for simplification of the description, the width of the laser beam L that is focused by the condenser lens 66 and irradiates the power meter 80 is the same as the width of the laser beam L that has passed through the slit S. ..

The control means 51 stores in the first storage unit 52 the amount of energy transmitted from the power meter 80, that is, the amount of energy of the laser beam L not shaded by the first plate 63 and the second plate 64, as a standard energy amount. To do.

As shown in FIG. 2, the control means 51 includes a first control unit 55 that controls the first movement mechanism 631 and a second control unit 56 that controls the W-axis direction movement means 67.
After storing the standard energy amount, the first control unit 55 of the control means 51 controls the first movement mechanism 631 to move the first plate 63 in the W1 direction as shown in FIG. 4, and causes the laser beam L. Bring it closer to the second plate 64, which is fixed in the open position, which is a position that does not block light.

At this time, the first control unit 55 moves the first plate 63 in the W1 direction until the measured value of the energy amount of the laser beam L by the power meter 80 becomes half of the standard energy amount. Then, the first control unit 55 acquires the position of the first plate 63 when the measured value of the energy amount of the laser beam L by the power meter 80 becomes half of the standard energy amount. The first control unit 55 stores the position of the first plate 63 in the second storage unit 53 as an intermediate position P1.

Further, the first control unit 55 controls the first moving mechanism 631 to bring the first plate 63 at the intermediate position P1 into contact with the second plate 64 fixed at the open position, as shown in FIG. Move in the W1 direction until For example, the first control unit 55 can electrically detect the contact between the first plate 63 and the second plate 64.

Then, the first control unit 55 acquires the moving distance along the W1 direction until the first plate 63 at the intermediate position P1 comes into contact with the second plate 64 at the open position as the contact distance D1. The first control unit 55 stores the acquired contact distance D1 in the third storage unit 54.

After that, in the state where the first plate 63 is in contact with the second plate 64 in the open position, the first control unit 55 has a distance between the first plate 63 and the second plate 64 as shown in FIG. The first plate 63 is moved in the W2 direction so as to have a predetermined slit width D0. As a result, the first control unit 55 forms the slit S having the slit width D0 by the first plate 63 and the second plate 64. The slit width D0 is an appropriate width of the slit S desired by the operator.

Next, the second control unit 56 of the control means 51 controls the W-axis direction moving means 67 to form the first plate 63 and the second plate 64 forming the slit S, as shown in FIG. They are moved together in the W2 direction by (contact distance D1-slit width D0 / 2). As a result, the center of the slit S formed by the first control unit 55 coincides with the center L1 of the optical axis of the laser beam L.

As described above, in the present embodiment, the control means 51 (first control unit 55 and second control unit 56) changes the positions of the first plate 63 and the second plate 64 to change the slit width of the slit S. Set D0 appropriately. Further, the control means 51 controls the positions of the first plate 63 and the second plate 64 according to the value of the slit width D0 so that the center of the slit S coincides with the center of the optical axis of the laser beam L. ..

As a result, in the present embodiment, even if the slit width D0 of the slit S, that is, the width of the dividing groove is changed, the center of the slit S and the center L1 of the optical axis of the laser beam L are made to match, and the shape of the dividing groove is formed. Can be maintained properly. Therefore, in the present embodiment, when the wafer 1 is ablated, the width of the dividing groove can be easily and freely changed.

Further, in the present embodiment, the shape of the dividing groove can be appropriately maintained even if the width of the dividing groove is changed, so that the depth of the dividing groove can be made uniform. Therefore, it is possible to suppress the division failure of the wafer 1.

[Embodiment 2]
In the present embodiment, the configuration of the energy distribution correcting means is different in the above-described first embodiment.
As shown in FIG. 8, the energy distribution correction means according to the present embodiment has an energy distribution correction device 62a instead of the energy distribution correction device 62 in the configuration of the energy distribution correction means shown in FIG. 2, and is a control means. It has control means 51a instead of 51.

The energy distribution corrector 62a does not include the W-axis direction moving means 67 in the configuration of the energy distribution corrector 62. Further, the control means 51a includes a third control unit 57 and a fourth control unit 58 in place of the first control unit 55 and the second control unit 56 in the configuration of the control means 51.

The third control unit 57 of the control means 51a controls the second movement mechanism 641 to move the second plate 64 along the W-axis direction. The fourth control unit 58 controls the first moving mechanism 631 and the second moving mechanism 641 to move the first plate 63 and the second plate 64 in opposite directions to each other.

In the energy distribution correction in the present embodiment, the control means 51a, as shown in FIG. 9, determines the amount of energy of the laser beam L that is not shielded by the first plate 63 and the second plate 64, as shown in the first embodiment. It is stored in the first storage unit 52 as a standard energy amount.

Next, the control means 51a controls the first movement mechanism 631 to move the first plate 63 in the W1 direction as shown in FIG. 10, and is fixed at an open position where the laser beam L is not shielded from light. Bring it closer to the 2 plate 64. The control means 51a moves the first plate 63 in the W1 direction until the measured value of the energy amount of the laser beam L by the power meter 80 becomes half of the standard energy amount. Then, the control means 51a acquires the position of the first plate 63 when the measured value of the energy amount of the laser beam L by the power meter 80 becomes half of the standard energy amount, and sets the intermediate position P1 in the second storage unit 53. Remember.

Next, in a state where the first plate 63 is in the intermediate position P1, the third control unit 57 of the control means 51a controls the second moving mechanism 641 to obtain the second plate 64 as shown in FIG. It is moved in the W2 direction and brought into contact with the first plate 63. For example, the third control unit 57 can electrically detect the contact between the first plate 63 and the second plate 64.

After that, the fourth control unit 58 of the control means 51a controls the first movement mechanism 631 and the second movement mechanism 641, and slits the first plate 63 and the second plate 64 contacted by the third control unit 57. Separate each other by half the width D0.
That is, the fourth control unit 58 controls the first movement mechanism 631 to move the first plate 63 in the W2 direction by D0 / 2, as shown in FIG. Further, the fourth control unit 58 controls the second moving mechanism 641 to move the second plate 64 in the W1 direction by D0 / 2. As a result, a slit S is formed between the first plate 63 and the second plate 64, and the center of the slit S coincides with the center L1 of the optical axis of the laser beam L.

Also in such an embodiment, the control means 51a (third control unit 57 and fourth control unit 58) changes the positions of the first plate 63 and the second plate 64 to reduce the slit width D0 of the slit S. It can be set appropriately and the center of the slit S can be aligned with the center of the optical axis of the laser beam L.
Thereby, even in the present embodiment, the shape of the dividing groove can be appropriately maintained according to the change of the slit width D0 of the slit S (that is, the change of the width of the dividing groove). Therefore, when the wafer 1 is ablated, the width of the dividing groove can be easily and freely changed.

1: Wafer, F: Ring frame, T: Adhesive tape, W: Workset,
10: Laser machining equipment, 20: Index feed means, 30: Machining feed means,
40: Chuck table, 43: Chuck table,
12: Laser processing means, 17: Arm part, 18: Processing head,
61: Laser oscillator, 62: Energy distribution corrector, 80: Power meter,
63: 1st plate, 64: 2nd plate, 65: Reflective mirror, 66: Condensing lens,
67: W-axis direction moving means, 631: 1st moving mechanism, 641: 2nd moving mechanism,
51: Control means, 52: 1st storage unit, 53: 2nd storage unit, 54: 3rd storage unit,
55: 1st control unit, 56: 2nd control unit 56, 57: 3rd control unit, 58: 4th control unit L: laser beam, L1: center of optical axis S: slit, D0: predetermined slit width, D1: Contact distance, P1: Intermediate position

Claims (3)

A chuck table that holds the work piece, a laser processing means that processes the work piece held on the chuck table by irradiation with a laser beam, and a chuck table that is relative to the laser processing means in the X-axis direction. A laser processing apparatus including a processing feed means for processing and feeding and an index feeding means for index feeding the chuck table in the Y-axis direction perpendicular to the X-axis direction with respect to the laser processing means. ,
The laser processing means is
A laser oscillator that oscillates a laser beam and
A condenser that collects the laser beam oscillated from the laser oscillator,
An energy distribution correcting means, which is arranged between the laser oscillator and the concentrator and corrects the energy distribution in the W-axis direction, which is the direction perpendicular to the traveling direction of the laser beam, to the Gaussian distribution whose base portion is vertical. With
The energy distribution correction means
The first plate that blocks one side of the laser beam in the W-axis direction,
A second plate that faces the first plate and blocks the other side of the laser beam in the W-axis direction.
A first moving mechanism that moves the first plate in the W-axis direction,
A second moving mechanism that moves the second plate in the W-axis direction,
A control means for controlling the first moving mechanism and the second moving mechanism is provided.
The control means controls the first moving mechanism and the second moving mechanism to form a slit having a predetermined slit width in which the center and the center of the optical axis of the laser beam are aligned with the first plate and the second. It is configured to form between the boards,
Laser processing equipment. The control means
A first storage unit that stores a standard energy amount, which is an energy amount measured by a power meter, of the first plate and a laser beam that is not shielded by the second plate.
With the power meter when either one of the first plate or the second plate is moved in the first direction approaching the other plate fixed in the open position which is the position where the laser beam is not blocked. A second storage unit that stores an intermediate position that is the position of one of the plates when the energy amount of the laser beam to be measured becomes half of the standard energy amount.
A third storage unit that stores the contact distance, which is the moving distance along the first direction until the one plate in the intermediate position comes into contact with the other plate in the open position.
In a state where the one plate is moved in the first direction and is in contact with the other plate in the open position, the distance between the first plate and the second plate is the slit width. A first control unit that forms a slit having the slit width by moving the first plate in a second direction opposite to the first direction.
In order to align the center of the slit formed by the first control unit with the center of the optical axis of the laser beam, the first plate and the second plate forming the slit are moved in the second direction. The second control unit that moves by (corresponding contact distance-the slit width / 2) and
To prepare
The laser processing apparatus according to claim 1. The control means
A first storage unit that stores a standard energy amount, which is an energy amount measured by a power meter, of the first plate and a laser beam that is not shielded by the second plate.
With the power meter when either one of the first plate or the second plate is moved in the first direction approaching the other plate fixed in the open position which is the position where the laser beam is not blocked. A second storage unit that stores an intermediate position that is the position of one of the plates so that the energy amount of the laser beam to be measured is half of the standard energy amount.
With the one plate in the intermediate position, the third control unit that moves the other plate in the second direction opposite to the first direction and makes contact with the one plate.
The first plate and the second plate contacted by the third control unit are placed at a distance of half the slit width, one plate in the second direction and the other plate in the first direction. A fourth control unit that has a center that coincides with the center of the optical axis of the laser beam and forms a slit with the slit width by moving and separating from each other.
To prepare
The laser processing apparatus according to claim 1.

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