A wafer grooving dual-light-path laser structure and cutting method

Abstract

The present invention aims to provide a wafer grooving dual-light-path laser structure and cutting method with a simple structure, capable of simultaneously operating with two thin light beams and a wide laser, and an independent laser module that can be adjusted to complete the cutting of two thin light beams and a wide laser. The present invention includes a dual-thin laser module and a wide laser module. The dual-thin laser module includes a first laser, and the first laser is respectively cooperated with a workpiece on an external moving stage through a first wave plate, a first beam expander, a first shutter, a beam splitting prism, and a first focusing lens. The wide laser module includes a second laser, and the second laser is respectively cooperated with a workpiece on an external moving stage through a second wave plate, a second beam expander, a second shutter, a photomask, an optical lens module, and a second focusing lens. The cutting method includes performing dual-thin light laser cutting by the dual-thin laser module, synchronously performing wide laser cutting by the wide laser module, and performing laser adjustment when a single laser fails. The present 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 grooving dual-light-path laser structure and a cutting method. Background Art

[0002] In various multi-channel processes in the semiconductor field, for the removal of the low-k dielectric layer in the scribe lane of the high-integration, high-performance, and thin-and-light low-k wafers, a laser ablation technique is adopted. Different laser beam morphologies are used to ablate semi-cut grooves with a specific morphology to complete a groove with a U-shaped structure. The current process is to first complete a type of double-fine-beam processing, then switch the laser parameters and the optical path module, and then perform another type of wide-laser-beam processing to complete the U-shaped groove in the scribe lane (specified area). Currently, the main problem of the laser cutting method is the processing efficiency. The double-fine beam and the wide laser beam cannot operate simultaneously. Only one type of beam can be completed first, and then other shaped beams need to be switched and retrieved for processing (mainly because one laser cannot operate different types and different parameter beams simultaneously). Secondly, since the equipment is only equipped with one laser device, when the laser breaks down and needs to be disassembled and repaired, the machine is in a downtime state and cannot continue production. If a wafer grooving dual-light-path laser structure and a cutting method with a simple structure, where the double-fine beam and the wide laser can operate simultaneously, and an independent laser module can be adjusted to complete the cutting of the double-fine beam and the wide laser, 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 deficiencies of the prior art and provide a wafer grooving dual-light-path laser structure and a cutting method with a simple structure, where the double-fine beam and the wide laser can operate simultaneously, and an independent laser module can be adjusted to complete the cutting of the double-fine beam and the wide laser.

[0004] The technical solution adopted by the present invention is as follows: The present invention includes a double-fine laser module and a wide-laser module. The double-fine laser module includes a first laser, and the first laser is respectively cooperated with a workpiece on an external moving stage through a first wave plate, a first beam expander, a first shutter, a beam splitting prism, and a first focusing lens. The wide-laser module includes a second laser, and the second laser is respectively cooperated with the workpiece on the external moving stage through a second wave plate, a second beam expander, a second shutter, a reticle, an optical lens module, and a second focusing lens.

[0005] Further, a polarization beam splitting prism is provided between the rear ends of the first wave plate and the second wave plate.

[0006] Further, the optical lens module includes a plano-convex optical lens and a plano-concave optical lens. Both ends of the plano-convex optical lens are matched with the optical mask and the plano-concave optical lens, and both ends of the plano-concave optical lens are matched with the plano-convex optical lens and the second focusing lens.

[0007] Further, the first laser is matched with the first wave plate through the first mirror; the polarization beam splitter prism is matched with the first beam expander through the second mirror; the first beam expander is matched with the first shutter through the third mirror; and the split beam prism is matched with the first focusing lens through the fourth mirror and the fifth mirror.

[0008] Further, the second laser is matched with the second beam expander through the second wave plate and the polarization beam splitter prism; the optical mask is matched with the optical lens module through the sixth mirror and the seventh mirror; and the optical lens module is matched with the second focusing lens through the eighth mirror.

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

[0010] A cutting method for a wafer grooving double-light-path laser structure is as follows:

[0011] Step A: The double-fine laser module performs double-fine laser cutting.

[0012] Step B: The wide laser module synchronously performs wide laser cutting.

[0013] Step C: Laser adjustment is performed when a single laser fails.

[0014] Among them, the double-fine laser cutting in step A includes the following sub-steps:

[0015] Step A1: The first laser emits a laser beam, which enters the first wave plate through the first mirror, and the angle is adjusted by the first wave plate. The first wave plate makes the beam vertically pass through the polarization beam splitter prism and enter the first beam expander through the second mirror.

[0016] Step A2: The beam enters the split beam prism through the first beam expander, the third mirror and the first shutter, generating two parallel beams of light.

[0017] Step A3: The two parallel beams of light enter the first focusing lens through the fourth mirror and the fifth mirror to form double-fine light beams, and double-fine light beam ablation is formed on the workpiece.

[0018] Among them, the wide laser cutting in step B includes the following sub-steps;

[0019] Step B1: The second laser synchronously emits a laser beam and adjusts the angle through a second waveplate. The beam propagates horizontally through a polarization beam splitter prism and enters a second beam expander.

[0020] Step B2: The second beam expander injects the beam into a sixth mirror and a seventh mirror through a second shutter and a mask, and then into an optical lens module for beam shaping.

[0021] Step B3: The beam after shaping enters a second focusing lens through an eighth mirror and forms a wide-beam ablation on the workpiece.

[0022] When the double-fine laser module described in step C fails, the adjustment of the wide-laser module includes the following sub-steps:

[0023] Step C1: The second laser emits a laser beam into the second waveplate. The beam angle is adjusted through the second waveplate, and then the beam passes through the polarization beam splitter prism and enters the second mirror. The double-fine beam ablation of the workpiece is achieved through step A.

[0024] Step C2: After the double-fine beam ablation is completed, the angle of the second waveplate is adjusted, and the wide-beam ablation of the workpiece is achieved through step B.

[0025] When the wide-laser module described in step C fails, the adjustment of the double-fine laser module includes the following sub-steps:

[0026] Step C3: The double-fine laser module achieves the double-fine beam ablation of the workpiece through step A.

[0027] Step C4: After the double-fine beam ablation is completed, the first mirror injects the beam into the first waveplate. The beam angle is adjusted through the first waveplate, and then the beam passes through the polarization beam splitter prism and enters the second beam expander. The wide-beam ablation of the workpiece is achieved through step B.

[0028] The beneficial effects of the present invention are as follows: The double laser heads respectively perform the cutting of double-fine laser and wide laser, enabling the double-fine beam and the wide laser to operate simultaneously, without the need for separate independent workstations for zoning cutting, greatly improving the work efficiency. When any one of the lasers fails and is under repair, there will be no downtime. With any one of the faults, the remaining laser can continue to complete the grooving processing task. It is possible to first complete the double-fine light processing and then complete the thick-beam processing, solving the problem that a single laser cannot continue the urgent production task due to the failure of the laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic structural diagram of the present invention;

[0030] Figure 2 isFigure 1 Enlarged view of D;

[0031] Figure 3 Schematic diagram of double thin beams and wide beam;

[0032] Figure 4 Schematic diagram of the cutting track of the workpiece to be processed;

[0033] Figure 5 Schematic diagram of ablation of the cutting track;

[0034] Figure 6 Schematic diagram of the cutting interface between the external moving stage and the workpiece to be processed. Detailed implementation manners

[0035] As Figures 1 to 6 shown, in this embodiment, the present invention includes a double thin laser module and a wide laser module. The double thin laser module includes a first laser 1, and the first laser 1 is respectively cooperated with a workpiece 8 on an external moving stage 7 through a first wave plate 2, a first beam expander 3, a first shutter 4, a beam splitting prism 5 and a first focusing lens 6. The wide laser module includes a second laser 9, and the second laser 9 is respectively cooperated with the workpiece 8 on the external moving stage 7 through a second wave plate 10, a second beam expander 11, a second shutter 12, a mask 13, an optical lens module 14 and a second focusing lens 15. Thus, it can be seen that the double laser heads respectively perform cutting of double thin laser and wide laser, enabling the double thin beams and the wide laser to work simultaneously, without the need to separate into independent workstations for partition cutting, greatly improving the working efficiency.

[0036] As Figure 1 shown, in this embodiment, a polarization beam splitting prism 16 is disposed between the rear ends of the first wave plate 2 and the second wave plate 10. Thus, it can be seen that when any one of the lasers fails and needs to be repaired, there will be no downtime. For any one of the faults, the remaining laser can continue to complete the grooving processing task. The polarization beam splitting prism 16 realizes the effect that two beams of laser pass through perpendicularly and parallelly respectively, and can realize the completion of double thin light processing first, and then the completion of thick beam processing, solving the problem that a laser cannot continue the urgent production task due to the failure of the laser.

[0037] As Figure 2 shown, in this embodiment, the optical lens module 14 includes a plano-convex optical lens 141 and a plano-concave optical lens 142. The two ends of the plano-convex optical lens 141 are cooperated with the mask 13 and the plano-concave optical lens 142, and the two ends of the plano-concave optical lens 142 are cooperated with the plano-convex optical lens 141 and the second focusing lens 15.

[0038] As Figure 1As shown in the figure, in this embodiment, the first laser 1 cooperates with the first wave plate 2 through the first mirror 17. The polarization beam splitter prism 16 cooperates with the first beam expander 3 through the second mirror 18. The first beam expander 3 cooperates with the first shutter 4 through the third mirror 19. The beam splitting prism 5 cooperates with the first focusing lens 6 through the fourth mirror 20 and the fifth mirror 21. Thus, it can be seen that the first mirror 17, the second mirror 18, the third mirror 19, the fourth mirror 20, and the fifth mirror 21 can realize the reflection of the first optical path, reducing the overall volume of the device and making the internal layout more reasonable.

[0039] As Figure 1 shown in the figure, 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 reticle 13 cooperates with the optical lens module 14 through the sixth mirror 22 and the seventh mirror 23. The optical lens module 14 cooperates with the second focusing lens 15 through the eighth mirror 24. Thus, it can be seen that the sixth mirror 22, the seventh mirror 23, and the eighth mirror 24 realize the reflection of the second optical path.

[0040] As Figure 1 shown in the figure, in this embodiment, the first wave plate 2 and the second wave plate 10 are set as half-wave plates.

[0041] The working principle of the present invention: Step A, the double-fine laser module performs double-fine laser cutting;

[0042] Step B, the wide laser module synchronously performs wide laser cutting;

[0043] Step C, laser adjustment is performed when a single laser fails;

[0044] Among them, the double-fine laser cutting in step A includes the following sub-steps:

[0045] Step A1, the first laser 1 emits a laser beam and enters the first wave plate 2 through the first mirror 17. Angle adjustment is performed through the first wave plate 2. The first wave plate 2 makes the beam vertically pass through the polarization beam splitter prism 16 and enter the first beam expander 3 through the second mirror 18;

[0046] Step A2, the beam enters the beam splitting prism 5 through the first beam expander 3, the third mirror 19, and the first shutter 4, generating two parallel beams of light;

[0047] Step A3, the two parallel beams of light enter the first focusing lens 6 through the fourth mirror 20 and the fifth mirror 21 to form a double-fine beam, and double-fine beam ablation is formed on the workpiece 8;

[0048] Among them, the wide laser cutting in step B includes the following sub-steps;

[0049] Step B1: The second laser 9 synchronously emits a laser beam and adjusts the angle through the second wave plate 10. The beam propagates horizontally through the polarization beam splitter prism 16 and enters the second beam expander 11.

[0050] Step B2: The second beam expander 11 injects the beam into the sixth mirror 22 and the seventh mirror 23 through the second shutter 12 and the mask 13, and then into the optical lens module 14 for beam shaping.

[0051] Step B3: The beam after shaping enters the second focusing mirror 15 through the eighth mirror 24, and a wide beam ablation is formed on the workpiece 8.

[0052] Among them, when the double-fine laser module fails in step C, the adjustment of the wide laser module includes the following sub-steps:

[0053] Step C1: The second laser 9 emits a laser into the second wave plate 10, adjusts the beam angle through the second wave plate 10, passes through the polarization beam splitter prism 16, and injects the beam into the second mirror 18, and realizes the ablation of the double-fine beam on the workpiece 8 through step A.

[0054] Step C2: After completing the ablation of the double-fine beam, adjust the angle of the second wave plate 10, and realize the ablation of the wide beam on the workpiece 8 through step B.

[0055] Among them, when the wide laser module fails in step C, the adjustment of the double-fine laser module includes the following sub-steps:

[0056] Step C3: The double-fine laser module realizes the ablation of the double-fine beam on the workpiece 8 through step A.

[0057] Step C4: After completing the ablation of the double-fine beam, the first mirror 17 injects the beam into the first wave plate 2, adjusts the angle through the first wave plate 2, passes through the polarization beam splitter prism 16, and injects the beam into the second beam expander 11, and realizes the ablation of the wide beam on the workpiece 8 through step B.

[0058] Although the embodiments of the present invention are described with actual solutions, they do not constitute a limitation to the meaning of the present invention. For those skilled in the art, the modifications of its implementation solutions according to this specification and the combinations with other solutions are obvious.

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), an optical mask (13), an optical lens module (14) and a second focusing mirror (15); a polarization beam splitter prism (16) is arranged between the rear end of the first wave plate (2) and the rear end of the second wave plate (10); the optical lens module (14) comprises a The invention comprises a plano-convex optical lens (141) and a plano-concave optical lens (142), wherein 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); the first laser (1) cooperates with the first wave plate (2) through a first reflector (17), the polarization beam splitter prism (16) cooperates with the first beam expander (3) through a second reflector (18), the first beam expander (3) cooperates with the first light gate (4) through a third reflector (19), and the beam splitter prism (5) cooperates with the first focusing lens (6) through a fourth reflector (20) and a fifth reflector (21).

2. The wafer slotting dual-light path laser structure according to claim 1, 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).

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

4. A cutting method for a wafer slotting dual-light path laser structure as claimed in claim 3, 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 in step C fail, 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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