Wafer grooving double-light-path laser structure and cutting method

Abstract

According to the wafer slotting double-light-path laser structure and the cutting method, the structure is simple, double thin light beams and wide laser can work at the same time, and the independent laser modules can be adjusted to complete double thin light beam and wide laser cutting. The device comprises a double-fine laser module and a wide laser module, the double-fine laser module comprises a first laser device, the first laser device is matched with a machined part on an external moving carrier through a first wave plate, a first beam expander, a first optical shutter, a beam splitting prism and a first focus lens, and the wide laser module comprises a second laser device. The second laser is matched with a workpiece on the external moving carrier through a second wave plate, a second beam expander, a second optical shutter, a photomask, an optical lens module and a second focus lens respectively; the cutting method comprises the steps that the double-fine-light laser module conducts double-fine-light laser cutting, the wide laser module conducts wide laser cutting synchronously, and laser adjustment is conducted when a single laser breaks down. The invention is applied to the technical field of product laser cutting.

Description

Technical Field

[0001] The present invention is applied to the technical field of laser cutting, and particularly relates to a wafer slotting dual-light path laser structure and a cutting method. Background Art

[0002] Among the various multi-processes in the semiconductor field, the removal of the lowk dielectric layer in the dicing road of the high-integration, high-performance and lightweight lowk wafer adopts laser ablation technology. Through different laser beam morphologies, a half-cut groove with a specific morphology is ablated to complete a U-shaped groove. The current process is to first complete a type of double fine light processing, and then switch the laser parameters and optical path module, and then perform another type of wide laser beam processing to complete the U-shaped groove in the dicing road (specified area). The current laser cutting method mainly has the problem of processing efficiency. The double fine beam and the wide laser beam cannot work at the same time. Only one type of beam can be completed first, and then switch to call other shaped beams for processing (one laser can not work with different types of beams with different parameters at the same time); secondly, because the equipment is equipped with only one laser device, when the laser fails and needs to be disassembled and repaired, the machine is in a downtime state and cannot continue production. If a wafer grooving dual-optical path laser structure and cutting method with a simple structure, dual fine beams and wide lasers that can operate simultaneously, and an independent laser module that can be adjusted to complete dual fine beams and wide laser cutting can be designed, the above problems can be solved. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a wafer grooving dual-light path laser structure and cutting method with a simple structure, dual fine beams and wide lasers that can operate simultaneously, and an independent laser module that can be adjusted to complete dual fine beams and wide laser cutting.

[0004] The technical solution adopted by the present invention is: the present invention includes a double-thin laser module and a wide laser module, the double-thin laser module includes a first laser, the first laser is respectively matched with the processing part on the external moving stage through a first wave plate, a first beam expander, a first optical gate, a beam splitter prism and a first focusing mirror, the wide laser module includes a second laser, the second laser is respectively matched with the processing part on the external moving stage through a second wave plate, a second beam expander, a second optical gate, a light cover, an optical lens module and a second focusing mirror.

[0005] Furthermore, a polarization beam splitter prism is arranged between the rear end of the first wave plate and the rear end of the second wave plate.

[0006] Furthermore, the optical lens module includes a plano-convex optical lens and a plano-concave optical lens, both ends of the plano-convex optical lens cooperate with the light cover and the plano-concave optical lens, and both ends of the plano-concave optical lens cooperate with the plano-convex optical lens and the second focusing lens.

[0007] Furthermore, the first laser cooperates with the first wave plate through a first reflector, the polarization beam splitter prism cooperates with the first beam expander through a second reflector, the first beam expander cooperates with the first light gate through a third reflector, and the beam splitter prism cooperates with the first focusing mirror through a fourth reflector and a fifth reflector.

[0008] Furthermore, the second laser cooperates with the second beam expander through the second wave plate and the polarization beam splitter prism, the light mask cooperates with the optical lens module through the sixth reflector and the seventh reflector, and the optical lens module cooperates with the second focusing mirror through the eighth reflector.

[0009] Further, the first wave plate and the second wave plate are configured as half wave plates.

[0010] A cutting method for a wafer slotting dual-light path laser structure, the cutting method is as follows: Step A, double-thin laser module performs double-thin laser cutting; Step B, the wide laser module performs wide laser cutting synchronously; Step C: perform laser adjustment when a single laser fails; The double fine beam laser cutting in step A includes the following subdivision steps: Step A1, a first laser emits a laser beam and injects it into a first wave plate through a first reflector, and the first wave plate adjusts the angle of the laser beam. The first wave plate vertically passes the laser beam through a polarization beam splitter prism and injects it into a first beam expander through a second reflector; Step A2, the light beam passes through the first beam expander, the third reflector and the first optical gate and enters the beam splitting prism to generate two parallel light beams; Step A3, two parallel light beams are incident on the first focusing mirror through the fourth reflecting mirror and the fifth reflecting mirror to form double fine light beams, and double fine light beam ablation is formed on the workpiece; The wide laser cutting in step B includes the following subdivision steps: Step B1, the second laser synchronously emits a laser beam and adjusts the angle through the second wave plate, and the beam propagates horizontally through the polarization beam splitter prism and enters the second beam expander; Step B2, the second beam expander injects the light beam into the sixth reflector and the seventh reflector through the second optical gate and the optical mask and injects the light beam into the optical lens module for beam shaping; Step B3, the shaped light beam is incident on the second focusing mirror through the eighth reflecting mirror, and forms a wide beam ablation on the workpiece; When the double thin laser modules fail in step C, the adjustment of the wide laser module includes the following subdivision steps: Step C1, the second laser emits laser light into the second wave plate, the second wave plate adjusts the beam angle and the beam is emitted into the second reflector through the polarization beam splitter prism, and the double fine beam ablation of the workpiece is achieved through step A; Step C2, after completing the ablation of the double thin beams, adjusting the angle of the second wave plate, and implementing the ablation of the workpiece with the wide beam through step B; When the wide laser module fails in step C, the adjustment of the double thin laser modules includes the following subdivision steps: Step C3, the dual-fine laser module realizes ablation of the workpiece with dual-fine beams through step A; Step C4, after completing the ablation of the double thin beams, the first reflector injects the beam into the first wave plate, adjusts the angle through the first wave plate and injects the beam into the second beam expander through the polarization beam splitter prism, and realizes the ablation of the wide beam of the workpiece through step B.

[0011] The beneficial effects of the present invention are as follows: dual laser heads respectively perform dual fine laser cutting and wide laser cutting, so that dual fine beams and wide lasers can operate simultaneously, and there is no need to separate independent workstations for partitioned cutting, which greatly improves work efficiency. When any one of the lasers fails to maintain, there will be no downtime. If any one fails, the remaining laser can continue to complete the grooving task, and can complete the dual fine light processing first, and then the coarse beam processing, which solves the problem that one laser cannot continue the urgently needed production task due to laser failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 yes Figure 1 Enlarged view of middle D; Figure 3 is a schematic diagram of a double thin beam and a wide beam; Figure 4 is a schematic diagram of a cutting path of the workpiece; Figure 5 It is a schematic diagram of ablation of a cutting path; Figure 6 It is a schematic diagram of the cutting interface between the external motion platform and the workpiece. DETAILED DESCRIPTION

[0013] like Figures 1 to 6As shown, in this embodiment, the present invention includes a double fine laser module and a wide laser module, the double fine laser module includes a first laser 1, the first laser 1 is matched with a processing piece 8 on an external moving stage 7 through a first wave plate 2, a first beam expander 3, a first light gate 4, a beam splitter prism 5 and a first focusing mirror 6, and the wide laser module includes a second laser 9, the second laser 9 is matched with the processing piece 8 on the external moving stage 7 through a second wave plate 10, a second beam expander 11, a second light gate 12, a light mask 13, an optical lens module 14 and a second focusing mirror 15. It can be seen that the double laser heads respectively perform cutting of the double fine laser and the wide laser, so that the double fine beam and the wide laser can operate at the same time, without the need to separate independent stations for partition cutting, which greatly improves the work efficiency.

[0014] like Figure 1 As shown, in this embodiment, a polarization beam splitter prism 16 is provided between the rear end of the first wave plate 2 and the rear end of the second wave plate 10. It can be seen that when any one of the lasers fails to be repaired, there will be no downtime. If any one fails, the remaining laser can continue to complete the slotting processing task. The polarization beam splitter prism 16 achieves the effect of two laser beams passing vertically and parallelly respectively, and can complete the double fine light processing first, and then complete the coarse light beam processing, which solves the problem that one laser cannot continue the urgent production task due to laser failure.

[0015] like Figure 2 As shown, in this embodiment, the optical lens module 14 includes a plano-convex optical lens 141 and a plano-concave optical lens 142, and the two ends of the plano-convex optical lens 141 cooperate with the light cover 13 and the plano-concave optical lens 142, and the two ends of the plano-concave optical lens 142 cooperate with the plano-convex optical lens 141 and the second focusing lens 15.

[0016] like Figure 1 As shown, in this embodiment, the first laser 1 cooperates with the first wave plate 2 through the first reflector 17, the polarization beam splitter prism 16 cooperates with the first beam expander 3 through the second reflector 18, the first beam expander 3 cooperates with the first light gate 4 through the third reflector 19, and the beam splitter prism 5 cooperates with the first focusing mirror 6 through the fourth reflector 20 and the fifth reflector 21. It can be seen that the first reflector 17, the second reflector 18, the third reflector 19, the fourth reflector 20 and the fifth reflector 21 can realize the reflection of the first light path, reduce the overall volume of the device, and make the internal layout more reasonable.

[0017] like Figure 1As shown, in this embodiment, the second laser 9 cooperates with the second beam expander 11 through the second wave plate 10 and the polarization beam splitter prism 16, the light mask 13 cooperates with the optical lens module 14 through the sixth reflector 22 and the seventh reflector 23, and the optical lens module 14 cooperates with the second focusing mirror 15 through the eighth reflector 24. It can be seen that the sixth reflector 22, the seventh reflector 23 and the eighth reflector 24 realize the reflection of the second light path.

[0018] like Figure 1 As shown, in this embodiment, the first wave plate 2 and the second wave plate 10 are configured as half wave plates.

[0019] The working principle of the present invention is as follows: Step A, a double-fine laser module performs double-fine laser cutting; Step B, the wide laser module performs wide laser cutting synchronously; Step C: perform laser adjustment when a single laser fails; The double fine beam laser cutting in step A includes the following subdivision steps: Step A1, the first laser 1 emits a laser beam and injects it into the first wave plate 2 through the first reflector 17, and the angle is adjusted by the first wave plate 2. The first wave plate 2 makes the light beam pass vertically through the polarization beam splitter prism 16 and injects it into the first beam expander 3 through the second reflector 18; Step A2, the light beam passes through the first beam expander 3, the third reflector 19 and the first optical shutter 4 and enters the beam splitting prism 5 to generate two parallel light beams; Step A3, the two parallel light beams are incident on the first focusing mirror 6 through the fourth reflecting mirror 20 and the fifth reflecting mirror 21 to form double fine light beams, and double fine light beam ablation is formed on the workpiece 8; The wide laser cutting in step B includes the following subdivision steps: Step B1, the second laser 9 synchronously emits a laser beam and adjusts the angle through the second wave plate 10, and the beam propagates horizontally through the polarization beam splitter prism 16 and enters the second beam expander 11; Step B2, the second beam expander 11 injects the light beam into the sixth reflector 22 and the seventh reflector 23 through the second optical shutter 12 and the optical mask 13 and injects the light beam into the optical lens module 14 for beam shaping; Step B3, the shaped light beam is incident on the second focusing mirror 15 through the eighth reflector 24, and forms a wide beam ablation on the workpiece 8; When the double thin laser modules fail in step C, the adjustment of the wide laser module includes the following subdivision steps: Step C1, the second laser 9 emits laser light into the second wave plate 10, the second wave plate 10 adjusts the beam angle and the beam is emitted into the second reflector 18 through the polarization beam splitter prism 16, and the double fine beam ablation of the workpiece 8 is achieved through step A; Step C2, after completing the ablation of the double thin beams, the angle of the second wave plate 10 is adjusted, and the wide beam ablation of the workpiece 8 is achieved through step B; When the wide laser module fails in step C, the adjustment of the double thin laser modules includes the following subdivision steps: Step C3, the dual-fine laser module realizes ablation of the workpiece 8 with dual-fine beams through step A; Step C4, after completing the ablation of the double fine beams, the first reflector 17 injects the light beam into the first wave plate 2, adjusts the angle through the first wave plate 2 and injects the light beam into the second beam expander 11 through the polarization beam splitter prism 16, and realizes the ablation of the wide beam of the workpiece 8 through step B.

[0020] Although the embodiments of the present invention are described with practical solutions, they do not constitute limitations on the meaning of the present invention. For those skilled in the art, it is obvious to modify the implementation scheme and combine it with other solutions based on this description.

Claims

1. A wafer slotting dual-optical path laser structure, comprising a dual thin laser module and a wide laser module, characterized in that: The double-thin laser module comprises a first laser (1), the first laser (1) being matched with a processing piece (8) on an external moving platform (7) through a first wave plate (2), a first beam expander (3), a first optical gate (4), a beam splitter prism (5) and a first focusing mirror (6); the wide laser module comprises a second laser (9), the second laser (9) being matched with the processing piece (8) on the external moving platform (7) through a second wave plate (10), a second beam expander (11), a second optical gate (12), a light mask (13), an optical lens module (14) and a second focusing mirror (15).

2. The wafer slotting dual-light path laser structure according to claim 1, characterized in that: A polarization beam splitting prism (16) is provided between the rear end of the first wave plate (2) and the rear end of the second wave plate (10).

3. The wafer slotting dual-light path laser structure according to claim 2, characterized in that: The optical lens module (14) comprises a plano-convex optical lens (141) and a plano-concave optical lens (142); two ends of the plano-convex optical lens (141) cooperate with the light cover (13) and the plano-concave optical lens (142); and two ends of the plano-concave optical lens (142) cooperate with the plano-convex optical lens (141) and the second focusing lens (15).

4. The wafer slotting dual-light path laser structure according to claim 3, characterized in that: The first laser (1) cooperates with the first wave plate (2) via a first reflector (17), the polarization beam splitter prism (16) cooperates with the first beam expander (3) via a second reflector (18), the first beam expander (3) cooperates with the first light gate (4) via a third reflector (19), and the beam splitter prism (5) cooperates with the first focusing mirror (6) via a fourth reflector (20) and a fifth reflector (21).

5. The wafer slotting dual-light path laser structure according to claim 4, characterized in that: The second laser (9) cooperates with the second beam expander (11) via the second wave plate (10) and the polarization beam splitter prism (16); the light mask (13) cooperates with the optical lens module (14) via a sixth reflector (22) and a seventh reflector (23); and the optical lens module (14) cooperates with the second focusing lens (15) via an eighth reflector (24).

6. The wafer slotting dual-light path laser structure according to claim 5, characterized in that: The first wave plate (2) and the second wave plate (10) are configured as half wave plates.

7. A cutting method for a wafer slotting dual-light path laser structure as claimed in claim 6, characterized in that: The cutting method is as follows: Step A, double-thin laser module performs double-thin laser cutting; Step B, the wide laser module performs wide laser cutting synchronously; Step C: perform laser adjustment when a single laser fails; The double fine beam laser cutting in step A includes the following subdivision steps: Step A1, a first laser (1) emits a laser beam and injects the laser beam into a first wave plate (2) through a first reflector (17), and the first wave plate (2) adjusts the angle of the laser beam. The first wave plate (2) directs the laser beam vertically through a polarization beam splitter prism (16) and injects the laser beam into a first beam expander (3) through a second reflector (18); Step A2, the light beam passes through the first beam expander (3), the third reflector (19) and the first optical gate (4) and enters the beam splitting prism (5), thereby generating two parallel light beams; Step A3, the two parallel light beams are incident on the first focusing mirror (6) through the fourth reflecting mirror (20) and the fifth reflecting mirror (21) to form a double fine light beam, and double fine light beam ablation is formed on the workpiece (8); The wide laser cutting in step B includes the following subdivision steps: Step B1, the second laser (9) synchronously emits a laser beam and adjusts the angle through the second wave plate (10), and the beam propagates horizontally through the polarization beam splitter prism (16) and enters the second beam expander (11); Step B2, the second beam expander (11) injects the light beam into the sixth reflector (22) and the seventh reflector (23) through the second optical shutter (12) and the optical mask (13), and then injects the light beam into the optical lens module (14) for beam shaping; Step B3, the shaped light beam is incident on the second focusing mirror (15) through the eighth reflecting mirror (24), and forms a wide beam ablation on the workpiece (8); When the double thin laser modules fail in step C, the adjustment of the wide laser module includes the following subdivision steps: Step C1, the second laser (9) emits laser light into the second wave plate (10), the beam angle is adjusted by the second wave plate (10) and the beam is emitted into the second reflector (18) through the polarization beam splitter prism (16), and the double fine beam ablation of the workpiece (8) is achieved through step A; Step C2, after completing the ablation of the double fine beams, adjusting the angle of the second wave plate (10), and implementing the ablation of the workpiece (8) with a wide beam through step B; When the wide laser module fails in step C, the adjustment of the double thin laser modules includes the following subdivision steps: Step C3, the dual-fine laser module realizes ablation of the workpiece (8) with dual-fine beams through step A; Step C4: After the ablation of the double thin beams is completed, the first reflector (17) injects the light beams into the first wave plate (2), adjusts the angle through the first wave plate (2) and injects the light beams into the second beam expander (11) through the polarization beam splitter prism (16), and ablation of the wide beam of the workpiece (8) is achieved through step B.

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