TWI881652B - Laser processing device, semiconductor chip and method for manufacturing semiconductor chip - Google Patents

Abstract

The laser processing device of the present invention comprises: a laser light irradiation unit, which irradiates a wafer on which a plurality of semiconductor chips are provided with laser light; a first imaging unit, which photographs the wafer; a second imaging unit, which is provided separately from the first imaging unit and photographs the wafer; and a lens switching unit, which is provided in the second imaging unit and switches a plurality of lenses with different magnifications.

Description

Laser processing device, semiconductor chip and method for manufacturing semiconductor chip

The present invention relates to a laser processing device, a semiconductor chip and a method for manufacturing a semiconductor chip, and more particularly to a laser processing device for processing a wafer having a plurality of semiconductor chips formed thereon, a semiconductor chip and a method for manufacturing a semiconductor chip.

Previously, there is a known cutting device for cutting a wafer having a plurality of semiconductor chips. For example, Japanese Patent Publication No. 2020-131335 discloses such a cutting device.

The above-mentioned Japanese Patent Publication No. 2020-131335 discloses a cutting device for cutting a wafer formed with a plurality of semiconductor chips. The cutting device is equipped with: a worktable that holds the wafer; a blade that cuts the wafer held on the worktable; and a camera that is arranged at a position opposite to the worktable to photograph the wafer for aligning the wafer. The camera is composed of a microscope and a camera, and the wafer is photographed at a high or low magnification by switching the lens of the microscope.

However, it is conceivable that the cutting device described in the above-mentioned Japanese Patent Publication No. 2020-131335 will cause position error when switching the lens of the microscope. Therefore, there is a problem that it is difficult to suppress the influence of the position error caused by switching the lens of the microscope.

The present invention is completed to solve the above-mentioned problems. One of the purposes of the present invention is to provide a laser processing device, a semiconductor chip and a method for manufacturing a semiconductor chip that can suppress the influence of position errors caused by switching multiple lenses.

In order to achieve the above-mentioned purpose, the laser processing device of the first aspect of the present invention comprises: a laser light irradiation unit, which irradiates laser light to a wafer on which a plurality of semiconductor chips are arranged; a first imaging unit, which photographs the wafer; a second imaging unit, which is arranged separately from the first imaging unit, photographs the wafer; and a lens switching unit, which is arranged in the second imaging unit, and switches a plurality of lenses with different magnifications.

In the laser processing device of the first aspect of the present invention, as described above, there are provided: a first imaging unit that photographs a wafer; a second imaging unit that is provided separately from the first imaging unit and photographs a wafer; and a lens switching unit that is provided in the second imaging unit and switches a plurality of lenses having different magnifications. In this way, the first imaging unit without the risk of position error due to switching a plurality of lenses and the second imaging unit that can switch a plurality of lenses can be used in combination. As a result, unlike the case where only the second imaging unit is provided, the influence of position error caused by switching a plurality of lenses can be suppressed.

In the laser processing device of the first aspect, it is preferred that the second imaging unit is configured to shoot at least at a lower magnification than the first imaging unit by switching a plurality of lenses using a lens switching unit. If so configured, the second imaging unit that shoots at a lower magnification than the first imaging unit can be used as an alignment imaging unit for rough alignment of the wafer, and the first imaging unit that shoots at a higher magnification than the second imaging unit can be used as an alignment imaging unit for high-precision alignment of the wafer. As a result, the wafer can be efficiently aligned in two stages.

In this case, it is preferable that the second imaging unit is configured to shoot at a lower magnification than the first imaging unit and a higher magnification than the first imaging unit by switching a plurality of lenses using a lens switching unit. If configured in this way, the second imaging unit that shoots at a higher magnification than the first imaging unit can be used as an inspection imaging unit for wafer inspection (inspection of laser processing results, etc.). In addition, the second imaging unit can be used as both an alignment imaging unit and an inspection imaging unit.

In the laser processing device of the first aspect, it is preferred to further include a control unit, which corrects the position error caused by the lens switching unit switching multiple lenses based on the images obtained by the first camera unit and the second camera unit respectively shooting the same shooting object. If so configured, the position error caused by the lens switching unit switching multiple lenses can be corrected, so the influence of the position error caused by the lens switching unit switching multiple lenses can be effectively suppressed.

In this case, it is preferred that the photographing object includes an alignment mark set on the wafer, and the control unit is configured to perform a photographing action of the alignment mark to correct the position error caused by the lens switching unit switching multiple lenses in parallel with the photographing action of the alignment mark by the first imaging unit or the second imaging unit for aligning the wafer. If configured in this way, there is no need to perform a dedicated photographing action to correct the position error caused by the lens switching unit switching multiple lenses, so that the time required for photographing can be shortened and the influence of the position error caused by the lens switching unit switching multiple lenses can be suppressed.

In the laser processing device of the first aspect, the lens switching unit preferably includes a motor for moving the plurality of lenses and an encoder for outputting information related to the positions of the plurality of lenses, and is configured to drive the motor based on the output of the encoder to position the plurality of lenses. If configured in this way, the plurality of lenses can be positioned with better accuracy than when the plurality of lenses are positioned mechanically by grooves, so that the position error caused by the lens switching unit switching the plurality of lenses can be suppressed.

In this case, it is preferred that the motor includes a direct drive motor. If so configured, unlike the case where the motor is connected to a plurality of lenses via an intermediate mechanism such as a conveyor belt or gear, position errors will not be generated by the intermediate mechanism, so the positioning of the plurality of lenses can be performed with better accuracy. As a result, the position error generated by the lens switching unit switching a plurality of lenses can be more easily suppressed.

In the laser processing device of the first aspect, it is preferred that the lens switching unit is configured to switch a plurality of lenses by rotation. If configured in this way, a plurality of lenses can be switched by simply rotating the plurality of lenses, so that a plurality of lenses can be switched with a compact structure.

In the laser processing device of the first aspect, it is preferred that the second imaging unit is disposed above the lens closest to the laser light irradiation unit among the plurality of lenses, and the lens switching unit is configured to change the magnification by switching the lens located below the second imaging unit. If so configured, the second imaging unit can be disposed near the laser light irradiation unit, so that the laser light irradiation unit and the second imaging unit can be integrated and configured smaller and more compactly.

The semiconductor chip of the second aspect of the present invention is manufactured by a laser processing device, which comprises: a laser light irradiation unit, which irradiates a wafer on which a plurality of semiconductor chips are arranged with laser light; a first imaging unit, which photographs the wafer; a second imaging unit, which is arranged separately from the first imaging unit, photographs the wafer; and a lens switching unit, which is arranged in the second imaging unit, and switches a plurality of lenses with different magnifications.

In the semiconductor chip of the second aspect of the present invention, as described above, there are provided: a first imaging unit that photographs the wafer; a second imaging unit that is provided separately from the first imaging unit and photographs the wafer; and a lens switching unit that is provided in the second imaging unit and switches a plurality of lenses having different magnifications. In this way, the first imaging unit without the risk of position error due to switching a plurality of lenses and the second imaging unit that can switch a plurality of lenses can be used in combination. As a result, unlike the case where only the second imaging unit is provided, the influence of position error caused by switching a plurality of lenses can be suppressed.

The manufacturing method of the semiconductor chip of the third aspect of the present invention includes the following steps: irradiating a wafer with a plurality of semiconductor chips with laser light by a laser light irradiation unit; photographing the wafer by a first imaging unit; photographing the wafer by a second imaging unit provided separately from the first imaging unit; and switching a plurality of lenses with different magnifications by a lens switching unit provided in the second imaging unit.

In the semiconductor chip manufacturing method of the third aspect of the present invention, as described above, there are provided: a first imaging unit that photographs the wafer; a second imaging unit that is provided separately from the first imaging unit and photographs the wafer; and a lens switching unit that is provided in the second imaging unit and switches a plurality of lenses having different magnifications. In this way, the first imaging unit without the risk of position error due to switching a plurality of lenses and the second imaging unit that can switch a plurality of lenses can be used in combination. As a result, unlike the case where only the second imaging unit is provided, the influence of position error caused by switching a plurality of lenses can be suppressed.

1: Slotting device

2: Tape attachment device

3: Cutting device (laser processing device)

4: Grinding device

5: Tape changing device

6: Expansion device

11: Box section

12: Laser irradiation unit

13: Electrical surface coating cleaning section

21: Box storage area

22: Robotic arm

23: Transportation organization

24: Protective tape attachment area

30: Cutting section

30a: Laser light irradiation unit

30b: Clamping table

30c: 1st camera unit

30d: Second camera unit

30e: Lens

30f: Lens

30g: Lens switching unit

31: Box section

31a: ontology

31b: Up and down movement mechanism

32: Wafer transport department

32a: Clamping the hand

32b: Y-direction moving mechanism

32c:Track section

32d: Adsorb hands

33: Control Department

41: First box section

42: Robotic arm

43: Adsorption and holding part

44: Grinding Department

44a: Rough grinding section

44b: Lapping and cutting section

44c: Fine grinding department

45: Fine grinding department

46: Crystal defect formation part

47: Second box section

48: Rotating table

51: Box storage section

52: Robotic arm

53:Transportation mechanism

54: Expansion tape attachment part

55: Ultraviolet irradiation part

100:Semiconductor wafer processing system

301b: Rotating mechanism

301c: Imaging components

301d: Imaging device

301g: Rotating body

301ga: Lens holding part

301gb:Connection

302b: Y-direction moving mechanism

302g: Motor

303b: X-direction moving mechanism

303g: Encoder

601: Box section

602: Lifting the hands

603: Adsorption of hands

604: Air conditioning supply department

605: Cooling unit

606: Expansion Department

607: Expansion and maintenance components

608: Heat shrinkage part

609: Ultraviolet irradiation unit

610: Extrusion unit

611: Clamping part

Ar: Alignment mark

Ar1: Alignment mark

Ar2: Alignment mark

Ax: rotation axis

Ch:Semiconductor chip

Dx1: Position offset

Dx2: Position offset

Dy1: Position offset

Dy2: Position offset

Im1:Image

Im2:Image

Im3:Image

Im4:Image

Im5:Image

Ld: Laser light

Lg: Laser light

Rf:Framework

S1: Steps

S2: Step

S3: Step

S4: Step

S5: Step

S6: Step

Ta: Shooting subject

Tb: Protective tape

Te: expansion tape

We: Wafer

Ws: cutting path

X: Direction

X1: Direction

X2: Direction

Y: Direction

Y1: Direction

Y2: Direction

Z: Direction

Z1: Direction

Z2: Direction

FIG1 is a schematic diagram showing an overview of a semiconductor wafer processing system equipped with a cutting device and an expanding device according to an embodiment.

FIG2 is a top view of a slotting device of a semiconductor wafer processing system according to an embodiment.

FIG3 is a top view of a tape attaching device of a semiconductor wafer processing system according to an embodiment.

FIG4 is a top view of a cutting device of a semiconductor wafer processing system according to an embodiment.

FIG5 is a top view of a polishing device of a semiconductor wafer processing system according to an embodiment.

FIG6 is a top view of a tape replacement device of a semiconductor wafer processing system according to an embodiment.

FIG. 7 is a side view of a tape replacement device of a semiconductor wafer processing system according to an embodiment.

FIG8 is a top view of an expansion device of a semiconductor wafer processing system according to an embodiment.

FIG. 9 is a side view showing an expansion device of a semiconductor wafer processing system according to an embodiment.

FIG. 10 is a flow chart showing a semiconductor chip manufacturing process of a semiconductor wafer processing system according to an embodiment.

FIG11 is a schematic top view showing a cutting device of an implementation method.

FIG12 is a schematic top view of a wafer in one embodiment.

FIG13 is a schematic diagram of the laser light irradiation unit, the first imaging unit, and the second imaging unit of an embodiment viewed from the Y2 direction.

FIG14 is a schematic diagram of the second imaging unit and the lens switching unit of an implementation method observed from the Y2 direction side.

Figure 15 is a schematic diagram of the second imaging unit and the lens switching unit of an implementation method observed from the Z1 direction side.

FIG. 16 is a schematic diagram for explaining a method for correcting position errors caused by switching lenses in one implementation.

FIG. 17 is a schematic diagram (1) for explaining an implementation method of shooting in parallel with the shooting action of the alignment mark to correct the position error caused by switching lenses.

FIG. 18 is a schematic diagram (2) used to illustrate an implementation method of shooting in parallel with the shooting action of the alignment mark to correct the position error caused by switching lenses.

The following is a description of the implementation method for embodying the present invention based on the drawings.

Referring to FIG. 1 to FIG. 18 , the structure of the semiconductor wafer processing system 100 according to the embodiment of the present invention is described.

(Semiconductor wafer processing system)

As shown in FIG. 1 , the semiconductor wafer processing system 100 is a device for processing a wafer We. The semiconductor wafer processing system 100 is configured to form a modified portion on the wafer We, and to divide the wafer We along the modified portion to form a plurality of semiconductor chips Ch. Here, the wafer We is a circular thin plate formed by a crystal of a semiconductor substance that is a material for a semiconductor integrated circuit. A modified portion is formed inside the wafer We, and the modified portion is formed by modifying the inside along a dividing line by processing in the semiconductor wafer processing system 100. That is, the wafer We is processed to be divisible along a dividing line. Here, the so-called modified portion refers to cracks and pores formed inside the wafer We by laser light Ld.

Specifically, the semiconductor wafer processing system 100 has a slotting device 1, a tape attaching device 2, a cutting device 3, a grinding device 4, a tape replacing device 5, and an expanding device 6. Furthermore, the cutting device 3 is an example of a "laser processing device" in the scope of the patent application.

As shown in FIG. 1 , in the semiconductor wafer processing system 100, the wafer We is processed in the order of the slotting device 1, the tape attaching device 2, the cutting device 3, the grinding device 4, the tape replacing device 5 and the expanding device 6.

〈Slotting device〉

The slotting device 1 is configured to irradiate the cutting road Ws between the semiconductor chips Ch along the electrical path of the wafer We without the frame Rf and the protective tape Tb installed, and separate the insulating film and the inspection pattern before the modified part is formed on the wafer We by the cutting device 3. Here, the laser light Lg is a light with a wavelength shorter than the infrared region. In addition, the so-called insulating film refers to the interlayer insulating film of the wafer We. The insulating film is formed of a Low-k material with a relatively low dielectric constant as an interlayer insulating film material. In addition, the so-called inspection pattern refers to a test conductive pattern used for functional testing of the semiconductor chip Ch of the wafer We. The inspection pattern is the so-called Teg (Test Element Group).

Specifically, as shown in FIG. 2 , the slotting device 1 includes a cassette section 11, a laser irradiation section 12, and a circuit surface film cleaning section 13. The cassette section 11 is configured to accommodate a wafer We without a frame Rf and a protective tape Tb installed. The laser irradiation section 12 is configured to irradiate a laser light Lg for separating the insulating film and the inspection pattern of the wafer We. The circuit surface film cleaning section 13 is configured to cover the circuit surface of the wafer We before separating the insulating film and the inspection pattern, and to clean the circuit surface of the wafer We after separating the insulating film and the inspection pattern.

〈Tape attaching device〉

The tape attaching device 2 is configured to attach the protective tape Tb to the electrical path of the wafer We (refer to FIG. 1 ).

Specifically, as shown in FIG3 , the tape attaching device 2 includes a cassette storage portion 21, a robot 22, a conveying mechanism 23, and a protective tape attaching portion 24. The cassette storage portion 21 is configured to accommodate a frame Rf, a wafer We, and a wafer We attached to the frame Rf. The robot 22 is configured to transport the frame Rf and the wafer We from the cassette storage portion 21 to the conveying mechanism 23, respectively. The robot 22 is configured to transport the wafer We attached to the frame Rf from the conveying mechanism 23 to the cassette storage portion 21. The conveying mechanism 23 is configured to transport the wafer We to a position where the protective tape attaching portion 24 can attach the protective tape Tb. The protective tape attaching section 24 is configured to attach the protective tape Tb to the wafer We transported by the transport mechanism 23, and to attach the frame Rf to the protective tape Tb.

〈Cutting device〉

The cutting device 3 is configured to form a modified portion inside the wafer We for dividing the wafer We (refer to FIG. 1 ).

Specifically, as shown in FIG. 4 , the cutting device 3 includes a cutting section 30, a cassette section 31, and a wafer conveying section 32. The cutting section 30 is configured to form a modified section by irradiating the wafer We with a laser light Ld (refer to FIG. 1 ) having a wavelength that is transparent along the cutting path Ws (dividing line). Here, the laser light Ld is a light with a wavelength in the near-infrared region. The cassette section 31 is configured to accommodate a plurality of wafers We attached to the protective tape Tb together with the frame Rf. The wafer conveying section 32 is configured to convey the wafer We attached to the protective tape Tb together with the frame Rf between the cassette section 31 and the cutting section 30.

〈Grinding device〉

The polishing device 4 is configured to remove the modified portion of the wafer We formed by the cutting device 3 by grinding the wafer We from the surface opposite to the electrical path surface side (see FIG. 1 ).

Specifically, as shown in FIG5 , the polishing device 4 includes a first cassette section 41, a robot 42, a plurality of adsorption holding sections 43, a plurality of grinding sections 44, a fine polishing section 45, a crystal defect forming section 46, a second cassette section 47, and a single rotary table section 48.

The first cassette section 41 is configured to accommodate the wafer We having the modified portion formed by the cutting device 3. The robot 42 is configured to transport the wafer We with the frame Rf attached thereto from the first cassette section 41 to the adsorption holding section 43 at the position closest to the first cassette section 41 among the plurality of adsorption holding sections 43. Furthermore, the robot 42 is configured to transport the wafer We with the modified portion removed and attached to the protective tape Tb together with the frame Rf from the adsorption holding section 43 at the position closest to the second cassette section 47 among the plurality of adsorption holding sections 43 to the second cassette section 47. The plurality of adsorption holding sections 43 are configured to adsorb and hold the wafer We attached to the protective tape Tb together with the frame Rf.

The plurality of grinding parts 44 are configured to grind the back side of the wafer We opposite to the electrical path surface in stages. The plurality of grinding parts 44 have a rough grinding part 44a, a fine grinding part 44b and a fine grinding part 44c. The rough grinding part 44a is configured to grind the back side of the wafer We by a first grinding material of a first particle size. The fine grinding part 44b is configured to grind the back side of the wafer We by a second grinding material of a second particle size smaller than the first particle size. The fine grinding part 44c is configured to grind the back side of the wafer We by a third grinding material of a third particle size smaller than the second particle size.

The fine grinding section 45 is configured to grind the back of the wafer We after being ground by the plurality of grinding sections 44. The crystal defect forming section 46 is configured to form tiny crystal defects on the back of the wafer We after being ground by the fine grinding section 45. The crystal defect forming section 46 is configured to perform a so-called gettering operation. The second cassette section 47 is configured to accommodate the wafer We with crystal defects formed by the crystal defect forming section 46. The single rotating table section 48 is configured to rotate and move the plurality of adsorption holding sections 43 to positions corresponding to the plurality of grinding sections 44, the fine grinding section 45 and the crystal defect forming section 46, respectively.

〈Tape changing device〉

The tape replacement device 5 is configured to attach the expansion tape Te to the surface of the wafer We opposite to the electrical path surface after the modified portion is removed from the wafer We by the polishing device 4, and to tear off the protective tape Tb attached to the electrical path surface of the wafer We (refer to FIG. 1).

Specifically, as shown in FIG6 , the tape replacement device 5 includes a cassette storage unit 51, a robot 52, a conveying mechanism 53, an expansion tape attachment unit 54, an ultraviolet irradiation unit 55 (see FIG7 ) and a protective tape stripping unit (not shown).

The cassette storage section 51 is configured to store a wafer We attached to the protective tape Tb together with the frame Rf, and a wafer We attached to the expansion tape Te together with the frame Rf.

The robot 52 is configured to transport the wafer We attached to the protective tape Tb together with the frame Rf from the cassette storage section 51 to the transport mechanism 53. The transport mechanism 53 is configured to transport the wafer We attached to the protective tape Tb together with the frame Rf to the expansion tape attachment section 54. The expansion tape attachment section 54 is configured to attach the frame Rf and the wafer We to both the protective tape Tb and the expansion tape Te by attaching the expansion tape Te to the surface of the frame Rf opposite to the surface to which the protective tape Tb is attached.

The robot 52 is configured to transport the wafer We attached to both the protective tape Tb and the expansion tape Te together with the frame Rf from the transport mechanism 53 to the ultraviolet irradiation unit 55. The ultraviolet irradiation unit 55 is configured to be located inside a closed structure with a door at the entrance and exit. After nitrogen is blown to remove oxygen in the ambient gas and the interior is filled with nitrogen (nitrogen is supplied to the interior, while oxygen is discharged and nitrogen is filled), ultraviolet rays are irradiated to the surface of the frame Rf attached with the protective tape Tb. In this way, the adhesive layer of the protective tape Tb is hardened. The robot 52 is configured to return the wafer We attached to both the protective tape Tb and the expansion tape Te together with the frame Rf from the ultraviolet irradiation unit 55 to the conveying mechanism 53.

The conveying mechanism 53 is configured to convey the wafer We attached to both the protective tape Tb and the expansion tape Te together with the frame Rf to the protective tape peeling section. The protective tape peeling section is configured to tear off the protective tape Tb (refer to FIG. 1 ). The robot 52 is configured to store the wafer We attached to the expansion tape Te together with the frame Rf in the cassette storage section 51 from the conveying mechanism 53.

〈Expansion device〉

The expansion device 6 is configured to adhere the expansion tape Te to the surface of the wafer We opposite to the electrical path surface, and then expand the expansion tape Te to divide the wafer We into a plurality of semiconductor chips Ch (refer to FIG. 1 ).

Specifically, as shown in FIG8 and FIG9, the expansion device 6 includes a box portion 601, a lifting hand portion 602, an adsorption hand portion 603, a cold air supply portion 604 (refer to FIG9), a cooling unit 605, an expansion portion 606, an expansion holding member 607, a heat shrinking portion 608 (refer to FIG9), an ultraviolet irradiation portion 609 (refer to FIG9), a squeezing portion 610 and a clamping portion 611.

The cassette section 601 is configured to accommodate a wafer ring structure W formed by attaching a frame Rf and a wafer We to an expansion tape Te. The lifting hand 602 is configured to take out the wafer ring structure W from the cassette section 601. The lifting hand 602 is configured to accommodate the wafer ring structure W in the cassette section 601. The suction hand 603 is configured to suction the frame Rf of the wafer ring structure W from above. The cold air supply section 604 is configured to supply cold air to the expansion tape Te from above when the expansion tape Te is expanded by the expansion section 606.

The cooling unit 605 is configured to cool the expansion tape Te from below. The expansion portion 606 is configured to divide the wafer We along the dicing line Ws (refer to FIG. 1 ) by expanding the expansion tape Te of the wafer ring structure W. The expansion holding member 607 is configured to press the expansion tape Te from above to prevent the expansion tape Te near the wafer We from shrinking due to the heating of the heat shrinking portion 608. The heat shrinking portion 608 is configured to shrink the expansion tape Te expanded by the expansion portion 606 by heating in a state where the gaps between the plurality of semiconductor chips Ch are maintained. The ultraviolet irradiation part 609 is configured to irradiate the expansion tape Te with ultraviolet rays so as to reduce the adhesive force of the adhesive layer of the expansion tape Te.

The squeezing part 610 is configured to further divide the wafer We along the modified part by squeezing the wafer We partially from the bottom side after the expansion tape Te is expanded. The clamping part 611 is configured to move the wafer ring structure W in the up and down directions while holding the frame Rf holding the wafer ring structure W. The clamping part 611 is configured to move the wafer ring structure W in the direction from the cooling unit 605 to the expansion part 606 and in the direction from the expansion part 606 to the cooling unit 605 while holding the frame Rf holding the wafer ring structure W.

(Semiconductor chip manufacturing process)

Below, referring to FIG. 10 , the overall operation of the semiconductor wafer processing system 100 is described.

In step S1, the insulating film and the inspection pattern are separated by the groove opening device 1. That is, the laser light irradiation unit 12 irradiates the laser light Lg along the cutting line Ws between the semiconductor chips Ch of the electrical path of the wafer We that is not attached to the protective tape Tb together with the frame Rf, and separates the insulating film and the inspection pattern. In step S2, the wafer We and the frame Rf are attached to the protective tape Tb by the tape attaching device 2. That is, the protective tape attaching unit 24 attaches the protective tape Tb to the wafer We transported by the transport mechanism 23, and attaches the frame Rf to the protective tape Tb.

In step S3, a modified portion is formed on the wafer We by the cutting device 3. That is, the cutting portion 30 forms the modified portion by irradiating the wafer We with laser light Ld (refer to FIG. 1 ) along the cutting path Ws. In step S4, the modified portion is removed from the wafer We by the grinding device 4. That is, the back side of the wafer We opposite to the electric path surface is ground in stages by a plurality of grinding portions 44, thereby removing the modified portion of the wafer We. In step S5, the expansion tape Te is attached to the wafer We and the frame Rf by the tape changing device 5, and then the protective tape Tb is torn off. That is, the expansion tape attaching portion 54 attaches the expansion tape Te to the frame Rf. The protective tape stripping section tears off the protective tape Tb from the wafer We attached to the frame Rf after the bonding layer of the protective tape Tb is hardened by the ultraviolet irradiation section 55.

In step S6, the expansion tape Te is expanded by the expansion device 6 to divide the wafer We into a plurality of semiconductor chips Ch. That is, the expansion tape Te abutting against the expansion part 606 is stretched downward by lowering the clamping part 611 while maintaining the frame Rf, thereby expanding the expansion tape Te. In this way, the wafer We is divided along the tortoise crack formed on the cutting path Ws of the wafer We by the tensile force generated by the expansion tape Te due to the expansion, thereby dividing a plurality of semiconductor chips Ch.

After step S6, the semiconductor chip manufacturing process is completed.

(Detailed structure of cutting device)

Referring to Figures 11 to 18, the structure of the cutting device 3 is described in detail.

As shown in FIG11 , the cutting device 3 includes a cutting unit 30, a cassette unit 31, a wafer conveying unit 32, and a control unit 33.

The cutting unit 30 includes a laser irradiation unit 30a, a fixture table unit 30b, a first imaging unit 30c, and a second imaging unit 30d. The second imaging unit 30d is provided separately from the first imaging unit 30c.

As shown in FIG. 11 and FIG. 12 , the laser irradiation unit 30a is configured to irradiate the laser light Ld to the wafer We provided with a plurality of semiconductor chips Ch (refer to FIG. 1 ). Specifically, the laser irradiation unit 30a is configured to irradiate the laser light Ld along each of the plurality of scribe lines Ws of the wafer We. More specifically, the laser irradiation unit 30a is configured to irradiate the laser light Ld along each of the plurality of scribe lines Ws of the wafer We by moving the wafer We relative to the laser irradiation unit 30a using the fixture table unit 30b.

As shown in FIG. 12 , a plurality of semiconductor chips Ch are arranged on the wafer We. The plurality of semiconductor chips Ch are arranged in a matrix on the wafer We. In addition, a straight-line cutting path Ws is provided between adjacent semiconductor chips Ch. The cutting path Ws includes a plurality of cutting paths Ws extending longitudinally and a plurality of cutting paths Ws extending transversely. In addition, alignment marks Ar for aligning the wafer We are provided on the plurality of semiconductor chips Ch, respectively.

As shown in FIG. 11 , the jig table portion 30b is configured to hold the wafer We. Specifically, the jig table portion 30b is configured to hold the wafer We attached to the frame Rf by adsorption, and the wafer We attached to the frame Rf is embedded in the wafer We of the frame Rf by adhering a protective tape Tb. The jig table portion 30b is configured to rotate or move in the horizontal direction in a state where the wafer We attached to the frame Rf is adsorbed. The jig table portion 30b has a rotating mechanism 301b, a Y-direction moving mechanism 302b, and an X-direction moving mechanism 303b. The jig table portion 30b is configured to move the wafer We relative to the laser light irradiation portion 30a when the laser light Ld is irradiated to the wafer We by the laser light irradiation portion 30a. Furthermore, the fixture table 30b is configured to move the wafer We relative to the first imaging unit 30c and the second imaging unit 30d when the wafer We is photographed by the first imaging unit 30c and the second imaging unit 30d.

The first imaging unit 30c and the second imaging unit 30d are respectively configured to photograph the wafer We held on the fixture table 30b from above (Z1 direction side). The first imaging unit 30c and the second imaging unit 30d are both near-infrared imaging cameras. The first imaging unit 30c and the second imaging unit 30d can move in the Z1 direction or the Z2 direction. In addition, the details of the first imaging unit 30c and the second imaging unit 30d will be described below.

The cassette section 31 is configured to store the wafer We attached to the frame Rf. Specifically, the cassette section 31 is configured to store a plurality of wafer We attached to the frame Rf. The cassette section 31 includes a main body 31a for storing a plurality of wafer boxes, and an up-and-down movement mechanism 31b for moving the main body 31a in the up-and-down direction (Z direction).

The wafer conveying unit 32 is configured to convey the wafer We with the frame Rf between the cassette unit 31 and the cutting unit 30. Specifically, the wafer conveying unit 32 has a clamping hand 32a, a Y-direction moving mechanism 32b, a rail unit 32c, and an adsorption hand 32d.

The clamping hand 32a is configured to transport the wafer We with the frame Rf between the cassette part 31 and the suction hand 32d. Specifically, the clamping hand 32a is configured to clamp the wafer We with the frame Rf to transport the wafer We with the frame Rf. The clamping hand 32a is configured to take out the wafer We with the frame Rf before laser processing from the cassette part 31 and transport it to the position of the suction hand 32d. In addition, the clamping hand 32a is configured to transport the wafer We with the frame Rf after laser processing from the position of the suction hand 32d to the cassette part 31.

The Y-direction moving mechanism 32b is configured to move the clamping hand 32a in the Y-direction. The clamping hand 32a is configured to transport the wafer We with the frame Rf by moving the Y-direction moving mechanism 32b in the Y-direction. The Y-direction moving mechanism 32b has, for example, a linear conveyor module or a drive unit, and the drive unit has a ball screw and a motor with an encoder.

The rail portion 32c is configured to support the wafer We with the frame Rf transported by the clamping hand 32a from below (Z2 direction side).

The suction hand 32d is configured to transfer the wafer We with the frame Rf before laser processing from the track portion 32c to the fixture table portion 30b. In addition, the suction hand 32d is configured to transfer the wafer We with the frame Rf after laser processing from the fixture table portion 30b to the track portion 32c. The suction hand 32d is configured to transfer the wafer We with the frame Rf by suction.

The control unit 33 is composed of various parts that control the cutting device 3. The control unit 33 includes a CPU (Central Processing Unit), and a memory unit having a ROM (Read Only Memory), a RAM (Random Access Memory), and an SSD (Solid State Drive). The control program for controlling the cutting device 3 is stored in the memory unit.

(Composition of the first imaging unit and the second imaging unit)

The first imaging unit 30c and the second imaging unit 30d are both alignment cameras. The first imaging unit 30c and the second imaging unit 30d are both configured to photograph the alignment mark Ar provided on the wafer We from above (Z1 direction side) when aligning the wafer We. Based on the image of the alignment mark Ar photographed by the second imaging unit 30d, the rough alignment (position correction) of the wafer We is performed. Furthermore, in a state where the rough alignment (position correction) of the wafer We has been performed, based on the image of the alignment mark Ar photographed by the first imaging unit 30c, the high-precision alignment (position correction) of the wafer We is performed. The alignment of the wafer We includes, for example, the alignment of the rotation direction of the wafer We, the alignment of the X direction and the Y direction of the wafer We, and the alignment of the Z direction of the wafer We.

As shown in FIG. 13 , the first imaging unit 30c is disposed on the X1 direction side relative to the laser light irradiation unit 30a. Furthermore, the second imaging unit 30d is disposed on the X2 direction side relative to the laser light irradiation unit 30a. The first imaging unit 30c and the second imaging unit 30d are disposed in the X direction across the laser light irradiation unit 30a. Furthermore, the first imaging unit 30c and the second imaging unit 30d both have imaging elements 301c and 301d. Furthermore, a lens 30e of a specified magnification is disposed in the first imaging unit 30c. The first imaging unit 30c is configured to shoot at a specified magnification (20 times, etc.) by using the lens 30e.

Here, in this embodiment, as shown in FIG. 13 to FIG. 15 , a lens switching unit 30g is provided in the second imaging unit 30d with a plurality of (4) lenses 30f having different switching magnifications.

Furthermore, the semiconductor chip Ch manufactured using the cutting device 3 is manufactured by the cutting device 3, and the cutting device 3 has: a laser irradiation unit 30a, which irradiates the laser light Ld to the wafer We on which the plurality of semiconductor chips Ch are arranged; a first imaging unit 30c, which photographs the wafer We; a second imaging unit 30d, which is separately arranged from the first imaging unit 30c, photographs the wafer We; and a lens switching unit 30g, which is arranged in the second imaging unit 30d, and switches a plurality of lenses 30f with different magnifications.

Furthermore, the manufacturing method of the semiconductor chip Ch using the cutting device 3 includes the following steps: irradiating the wafer We on which the plurality of semiconductor chips Ch are provided with laser light Ld by the laser light irradiation unit 30a; photographing the wafer We by the first imaging unit 30c; photographing the wafer We by the second imaging unit 30d provided separately from the first imaging unit 30c; and switching the plurality of lenses 30f having different magnifications by the lens switching unit 30g provided in the second imaging unit 30d.

Furthermore, in the present embodiment, the lens switching unit 30g is configured to switch the plurality of lenses 30f by rotating. Specifically, the lens switching unit 30g is configured to switch the plurality of lenses 30f by rotating the rotating body 301g including the plurality of lenses 30f around the rotation axis Ax extending in the up-down direction (Z direction) so that the plurality of lenses 30f are rotated as a whole. The rotating body 301g has a plurality of (4) lens holding units 301ga that respectively hold the lenses 30f, and a connecting unit 301gb that connects the plurality of lens holding units 301ga to each other.

In addition, in the present embodiment, the lens switching unit 30g includes a motor 302g that moves the plurality of lenses 30f, and an encoder 303g that outputs information related to the positions of the plurality of lenses 30f. The motor 302g includes a direct drive motor. Specifically, the output shaft of the motor 302g is directly connected to the connecting portion 301gb of the rotating body 301g without passing through an intermediate mechanism such as a gear or a conveyor belt. The motor 302g is configured to rotate the rotating body 301g around the rotation axis Ax under the control of the control unit 33.

The encoder 303g is configured to obtain information related to the rotational position of the motor 302g and output the obtained information. The information related to the rotational position of the motor 302g is information related to the position of the plurality of lenses 30f. The control unit 33 drives the motor 302g based on the output of the encoder 303g, thereby positioning (switching) the plurality of lenses 30f. Furthermore, in the lens switching unit 30g, there is no mechanical positioning mechanism such as a groove for positioning the plurality of lenses 30f at the switched position.

Furthermore, in this embodiment, the imaging element 301d of the second imaging unit 30d is arranged above (on the Z1 direction side) the lens 30f (the lens 30f closest to the X1 direction side) among the plurality of lenses 30f. The lens switching unit 30g is configured to change the magnification by switching the lens 30f located below (on the Z2 direction side) the imaging element 301d of the second imaging unit 30d.

The second imaging unit 30d is configured to shoot at least at a lower magnification than the first imaging unit 30c by switching the plurality of lenses 30f using the lens switching unit 30g. Specifically, the second imaging unit 30d is configured to shoot at a lower magnification than the first imaging unit 30c and a higher magnification than the first imaging unit 30c by switching the plurality of lenses 30f using the lens switching unit 30g. That is, the plurality of lenses 30f include lenses having a lower magnification than the lens 30e of the first imaging unit 30c and lenses having a higher magnification than the lens 30e of the first imaging unit 30c. For example, the plurality of (4) lenses 30f include a 2.5x lens, a 50x lens, a 100x lens, and a 200x lens.

The lens 30f with a lower magnification (2.5 times, etc.) than the lens 30e of the first imaging unit 30c can be used for the alignment of the wafer We. That is, when performing the rough alignment of the wafer We, the second imaging unit 30d is configured to photograph the alignment mark Ar of the wafer We at a lower magnification than the first imaging unit 30c by using the lens 30f with a lower magnification than the lens 30e of the first imaging unit 30c.

Furthermore, the lens 30f having a higher magnification (50 times, 100 times, 200 times, etc.) than the lens 30e of the first imaging unit 30c can be used for inspection of the wafer We (inspection of the laser processing result, etc.). That is, when inspecting the wafer We, the second imaging unit 30d is configured to photograph the inspection object of the wafer We at a higher magnification than the first imaging unit 30c by using the lens 30f having a higher magnification than the lens 30e of the first imaging unit 30c. The inspection object of the wafer We is not particularly limited, and for example, laser processing marks (cutting marks) formed along the cutting street Ws can be cited. The laser processing mark (about 1μm) is smaller than the alignment mark Ar (about 50μm), so it cannot be easily photographed using the magnification of the first imaging unit 30c that photographs the alignment mark Ar.

(Correction of position error caused by switching lenses)

In addition, in this embodiment, as shown in FIG16, the control unit 33 is configured to correct the position error caused by the lens switching unit 30g switching the plurality of lenses 30f based on the images obtained by the first imaging unit 30c and the second imaging unit 30d respectively capturing the same imaging object Ta. Furthermore, for the sake of convenience, FIG16 illustrates the imaging object Ta presented in each image with the same size, but in fact, since the magnification of each imaging unit is different, the size of the imaging object Ta presented in each image is actually different.

Specifically, the control unit 33 is configured to correct the position error caused by the lens switching unit 30g switching the plurality of lenses 30f based on the position of the photographed object Ta in the image Im1 obtained by photographing the photographed object Ta by the first imaging unit 30c and the position of the photographed object Ta in the image Im2 obtained by photographing the photographed object Ta by the second imaging unit 30d.

More specifically, the control unit 33 is configured to obtain the position offsets Dx1 and Dy1 of the photographed object Ta relative to the center of the image Im1 based on the image Im1. Furthermore, the position offset Dx1 indicates the position offset of the photographed object Ta relative to the center of the image Im1 in the X direction. Furthermore, the position offset Dy1 indicates the position offset of the photographed object Ta relative to the center of the image Im1 in the Y direction.

Furthermore, the control unit 33 is configured to obtain the position offsets Dx2 and Dy2 of the photographed object Ta relative to the center of the image Im2 based on the image Im2. Furthermore, the position offset Dx2 indicates the position offset of the photographed object Ta relative to the center of the image Im2 in the X direction. Furthermore, the position offset Dx2 includes, in addition to the position offset Dx1, the position offset caused by the position error caused by switching multiple lenses 30f. Furthermore, the position offset Dy2 indicates the position offset of the photographed object Ta relative to the center of the image Im2 in the Y direction. Furthermore, the position offset Dy2 includes, in addition to the position offset Dy1, the position offset caused by the position error caused by switching multiple lenses 30f.

The control unit 33 is configured to obtain the difference Dx2-Dx1 between the position offset Dx1 and the position offset Dx2, and to obtain the difference Dy2-Dy1 between the position offset Dy1 and the position offset Dy2. The difference Dx2-Dx1 represents the position offset in the X direction caused by the position error generated by switching the plurality of lenses 30f. Furthermore, the difference Dy2-Dy1 represents the position offset in the Y direction caused by the position error generated by switching the plurality of lenses 30f. Therefore, the control unit 33 is configured to obtain the difference Dx2-Dx1 as the correction value in the X direction, and to obtain the difference Dy2-Dy1 as the correction value in the Y direction. Furthermore, the control unit 33 is configured to correct the position error caused by the lens switching unit 30g switching the plurality of lenses 30f based on the difference Dx2-Dx1 and the difference Dy2-Dy1 as correction values.

In addition, in this embodiment, as shown in FIG. 17 , the photographed object Ta includes the alignment mark Ar provided on the wafer We. The control unit 33 is configured to perform a photographing operation of the alignment mark Ar for correcting the position error caused by the lens switching unit 30g switching the plurality of lenses 30f in parallel with the photographing operation of the alignment mark Ar photographed by the first imaging unit 30c or the second imaging unit 30d for aligning the wafer We.

For example, it is conceivable that a low-magnification lens 30f is used to photograph the alignment mark Ar1 by the second imaging unit 30d for rough alignment, and the first imaging unit 30c photographs the alignment marks Ar1 and Ar2 for high-precision alignment.

In this case, as shown in Figures 17 and 18, first, the control unit 33 controls the second imaging unit 30d to shoot the alignment mark Ar1. Then, the control unit 33 controls the first imaging unit 30c to shoot the alignment mark Ar1. Then, the control unit 33 obtains the difference between the detection position of the alignment mark Ar1 in the image Im3 of the alignment mark Ar1 shot by the second imaging unit 30d and the detection position of the alignment mark Ar1 in the image Im4 of the alignment mark Ar1 shot by the first imaging unit 30c, and uses it as a correction value for correcting the position error caused by the lens switching unit 30g switching the plurality of lenses 30f.

Then, the control unit 33 performs the following control: the obtained correction value is added to determine the moving target position of the first imaging unit 30c for photographing the alignment mark Ar2 by the first imaging unit 30c. In this way, the alignment mark Ar2 can be photographed by the first imaging unit 30c at a position where the position error caused by the lens switching unit 30g switching the plurality of lenses 30f has been corrected. As a result, in the image Im5 of the alignment mark Ar2 photographed by the first imaging unit 30c, the alignment mark Ar2 can be presented at a position closer to the center of the image Im5. Furthermore, the correction values obtained thereafter are valid until the lens is switched again, so the first imaging unit 30c can continue to shoot the alignment mark Ar at the position where the position error caused by the lens switching unit 30g switching multiple lenses 30f has been corrected.

(Effects of this implementation method)

In this implementation method, the following effects can be obtained.

In this embodiment, as described above, there are provided: a first imaging unit 30c, which photographs the wafer We; a second imaging unit 30d, which is provided separately from the first imaging unit 30c, and photographs the wafer We; and a lens switching unit 30g, which is provided in the second imaging unit 30d, and switches a plurality of lenses 30f having different magnifications. In this way, the first imaging unit 30c, which is free from the risk of position error caused by switching a plurality of lenses 30f, and the second imaging unit 30d, which can switch a plurality of lenses 30f, can be used in combination. As a result, unlike the case where only the second imaging unit 30d is provided, the influence of the position error caused by switching a plurality of lenses 30f can be suppressed.

Furthermore, in the present embodiment, as described above, the second imaging unit 30d is configured to shoot at least at a lower magnification than the first imaging unit 30c by switching a plurality of lenses 30f using the lens switching unit 30g. In this way, the second imaging unit 30d that shoots at a lower magnification than the first imaging unit 30c can be used as an alignment imaging unit for rough alignment of the wafer We, and the first imaging unit 30c that shoots at a higher magnification than the second imaging unit 30d can be used as an alignment imaging unit for high-precision alignment of the wafer We. As a result, the alignment of the wafer We can be efficiently performed in two stages.

Furthermore, in the present embodiment, as described above, the second imaging unit 30d is configured to shoot at a lower magnification than the first imaging unit 30c and a higher magnification than the first imaging unit 30c by switching a plurality of lenses 30f using the lens switching unit 30g. In this way, the second imaging unit 30d that shoots at a higher magnification than the first imaging unit 30c can be used as an inspection imaging unit for inspecting the wafer We (inspection of laser processing results, etc.). Furthermore, the second imaging unit 30d can be used as both an alignment imaging unit and an inspection imaging unit.

In addition, in the present embodiment, as described above, a control unit is further provided, and the control unit corrects the position error caused by the lens switching unit 30g switching the plurality of lenses 30f based on the images obtained by the first imaging unit 30c and the second imaging unit 30d respectively capturing the same imaging object. In this way, the position error caused by the lens switching unit 30g switching the plurality of lenses 30f can be corrected, so the influence of the position error caused by the lens switching unit 30g switching the plurality of lenses 30f can be effectively suppressed.

Furthermore, in the present embodiment, as described above, the photographing object includes the alignment mark Ar provided on the wafer We, and the control unit is configured to perform a photographing action of the alignment mark Ar for correcting the position error caused by the lens switching unit 30g switching a plurality of lenses 30f in parallel with the photographing action of the alignment mark Ar photographed by the first imaging unit 30c or the second imaging unit 30d for aligning the wafer We. In this way, there is no need to perform a dedicated shooting operation to correct the position error caused by the lens switching unit 30g switching multiple lenses 30f, so the time required for shooting can be shortened and the influence of the position error caused by the lens switching unit 30g switching multiple lenses 30f can be suppressed.

Furthermore, in the present embodiment, as described above, the lens switching unit 30g includes a motor 302g for moving the plurality of lenses 30f, and an encoder 303g for outputting information related to the positions of the plurality of lenses 30f, and is configured to drive the motor 302g based on the output of the encoder 303g, thereby positioning the plurality of lenses 30f. In this way, the plurality of lenses 30f can be positioned with good accuracy compared to the case where the plurality of lenses 30f are positioned mechanically by a groove, so that the position error caused by the lens switching unit 30g switching the plurality of lenses 30f can be suppressed.

Furthermore, in the present embodiment, as described above, the motor 302g includes a direct drive motor. Thus, unlike the case where the motor 302g is connected to the plurality of lenses 30f via an intermediate mechanism such as a conveyor belt or a gear, position errors will not be generated due to the intermediate mechanism, so the plurality of lenses 30f can be positioned with better accuracy. As a result, the position errors generated by the lens switching unit 30g switching the plurality of lenses 30f can be more easily suppressed.

Furthermore, in the present embodiment, as described above, the lens switching unit 30g is configured to switch a plurality of lenses 30f by rotation. In this way, a plurality of lenses 30f can be switched by simply rotating the plurality of lenses 30f, so a plurality of lenses 30f can be switched with a compact structure.

Furthermore, in the present embodiment, as described above, the second imaging unit 30d is disposed above the lens 30f closest to the laser light irradiation unit among the plurality of lenses 30f, and the lens switching unit 30g is configured to change the magnification by switching the lens 30f located below the second imaging unit 30d. In this way, the second imaging unit 30d can be disposed near the laser light irradiation unit, so that the laser light irradiation unit and the second imaging unit 30d can be integrated and disposed in a smaller and more compact manner.

[Example of changes]

Furthermore, the embodiments disclosed this time should be regarded as illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the scope of the patent application, not by the description of the above embodiments, and includes all changes (variations) within the meaning and scope equivalent to the scope of the patent application.

For example, in the above-mentioned embodiment, an example of applying the present invention to a cutting device as a laser processing device is shown, but the present invention is not limited to this. The present invention can also be applied to a slotting device as a laser processing device.

Furthermore, in the above-mentioned embodiment, an example of 4 lenses being provided relative to the second imaging unit is shown, but the present invention is not limited thereto. In the present invention, 2, 3, or 5 or more lenses may also be provided relative to the second imaging unit.

Furthermore, in the above-mentioned embodiment, the second imaging unit is configured to shoot at a lower magnification than the first imaging unit and a higher magnification than the first imaging unit by switching a plurality of lenses using the lens switching unit, but the present invention is not limited to this. In the present invention, the second imaging unit may also be configured to shoot only at a lower magnification than the first imaging unit by switching a plurality of lenses using the lens switching unit. In this case, the plurality of lenses switched by the lens switching unit may also include a low magnification lens for alignment and a low magnification lens for inspection. If a low-magnification lens is included for inspection, a larger area of the wafer can be captured, so a larger area of the wafer can be roughly inspected at one time.

Furthermore, in the above-mentioned embodiment, an example is shown in which the photographing object used to correct the position error caused by the lens switching unit switching multiple lenses includes an alignment mark, but the present invention is not limited to this. In the present invention, the photographing object used to correct the position error caused by the lens switching unit switching multiple lenses may also include objects other than alignment marks. For example, the photographing object used to correct the position error caused by the lens switching unit switching multiple lenses may also be a correction-specific mark set in the device.

Furthermore, in the above-mentioned embodiment, an example is shown in which the photographing object used to correct the position error caused by the lens switching unit switching a plurality of lenses includes a dedicated alignment mark respectively set on a plurality of semiconductor chips, but the present invention is not limited to this. In the present invention, the photographing object used to correct the position error caused by the lens switching unit switching a plurality of lenses may also include an alignment mark as the corner of each of the plurality of semiconductor chips.

Furthermore, in the above-mentioned embodiment, an example is shown in which a mechanical positioning mechanism is not provided in the lens switching part, but the present invention is not limited to this. In the present invention, a mechanical positioning mechanism can also be provided in the lens switching part.

Furthermore, in the above-mentioned embodiment, an example is shown in which the motor includes a direct drive motor, but the present invention is not limited to this. In the present invention, the motor can also be connected to a rotating body including a plurality of lenses via an intermediate mechanism such as a gear or a conveyor belt.

Furthermore, in the above-mentioned embodiment, an example is shown in which the lens switching unit is configured to switch multiple lenses by rotation, but the present invention is not limited to this. In the present invention, the lens switching unit can also be configured to switch multiple lenses by sliding movement.

Furthermore, in the above-mentioned embodiment, an example is shown in which the second imaging unit is arranged above the lens closest to the laser light irradiation unit among the plurality of lenses, but the present invention is not limited to this. In the present invention, the second imaging unit can also be arranged above any lens among the plurality of lenses.

Furthermore, in the above-mentioned embodiment, an example is shown in which the first imaging unit and the second imaging unit move relative to the wafer by moving the wafer, but the present invention is not limited to this. In the present invention, the first imaging unit and the second imaging unit may also move relative to the wafer by moving the first imaging unit and the second imaging unit.

In addition, in the above-mentioned embodiment, for the convenience of explanation, an example of using a process-driven flowchart in which processing is performed sequentially according to the processing flow is shown to explain the control processing, but the present invention is not limited to this. In the present invention, control processing can also be performed by event-driven (event-driven) processing in which processing is performed in units of events. In this case, a complete event-driven type can be used, or a combination of event-driven and process-driven can be used.

30a: Laser light irradiation unit

30c: 1st camera unit

30d: Second camera unit

30e: Lens

30f: Lens

30g: Lens switching unit

301c: Imaging components

301d: Imaging device

301g: Rotating body

301ga: Lens holding part

301gb:Connection

302g: Motor

303g: Encoder

X: Direction

X1: Direction

X2: Direction

Y: Direction

Y1: Direction

Y2: Direction

Z: Direction

Z1: Direction

Z2: Direction

Claims (10)

A laser processing device comprises: a laser irradiation unit for irradiating a wafer on which a plurality of semiconductor chips are disposed with laser light; a first imaging unit for photographing the wafer; a second imaging unit for photographing the wafer separately from the first imaging unit; a lens switching unit for switching a plurality of lenses having different magnifications provided in the second imaging unit; and a control unit for correcting position errors caused by the lens switching unit switching the plurality of lenses based on images obtained by the first imaging unit and the second imaging unit photographing the same object. As in claim 1, the laser processing device, wherein the second imaging unit is configured to shoot at a magnification lower than that of the first imaging unit by switching the plurality of lenses using the lens switching unit. As in claim 2, the laser processing device, wherein the second imaging unit is configured to shoot at a lower magnification than the first imaging unit and at a higher magnification than the first imaging unit by switching the plurality of lenses using the lens switching unit. As in claim 1, the laser processing device, wherein the photographing object includes an alignment mark provided on the wafer, and the control unit is configured to perform a photographing action of the alignment mark to correct the position error caused by the lens switching unit switching the plurality of lenses in parallel with the photographing action of the alignment mark photographed by the first imaging unit or the second imaging unit for aligning the wafer. As in claim 1, the laser processing device, wherein the lens switching unit includes a motor for moving the plurality of lenses, and an encoder for outputting information related to the positions of the plurality of lenses, and is configured to drive the motor based on the output of the encoder, thereby positioning the plurality of lenses. As in claim 5, the laser processing device, wherein the motor includes a direct drive motor. As in claim 1, the laser processing device, wherein the lens switching unit is configured to switch the plurality of lenses by rotation. As in claim 1, the laser processing device, wherein the second imaging unit is disposed above the lens closest to the laser light irradiation unit among the plurality of lenses, and the lens switching unit is configured to change the magnification by switching the lens located below the second imaging unit. A semiconductor chip is manufactured by a laser processing device, wherein the laser processing device comprises: a laser irradiation unit, which irradiates a wafer on which a plurality of semiconductor chips are disposed, with laser light; a first imaging unit, which photographs the wafer; a second imaging unit, which is disposed separately from the first imaging unit, and photographs the wafer; a lens switching unit, which is disposed in the second imaging unit, and switches a plurality of lenses having different magnifications; and a control unit, which corrects position errors caused by the lens switching unit switching the plurality of lenses based on images obtained by the first imaging unit and the second imaging unit respectively photographing the same object. A method for manufacturing a semiconductor chip comprises the following steps: irradiating a wafer on which a plurality of semiconductor chips are disposed with laser light by a laser light irradiation unit; photographing the wafer by a first imaging unit; photographing the wafer by a second imaging unit disposed separately from the first imaging unit; switching a plurality of lenses having different magnifications by a lens switching unit disposed in the second imaging unit; and correcting position errors caused by switching the plurality of lenses by the lens switching unit based on images obtained by photographing the same object by the first imaging unit and the second imaging unit, respectively.