Laser precision machining device and method for dynamically adjusting beam shaping based on light field imaging

Abstract

The invention relates to the technical field of laser precision machining, and discloses a laser precision machining device and method for dynamically adjusting beam shaping based on light field imaging, and the device comprises a laser emission unit, an X-axis movable laser reflector, an X-axis and Y-axis movable laser reflector, a dynamic shaping module and a focusing galvanometer system. The laser emitting unit, the X-axis movable laser reflecting mirror, the X-axis and Y-axis movable laser reflecting mirror, the dynamic shaping module and the focusing galvanometer system are all fixed to a support at the top of the supporting table. According to the invention, based on a specially designed laser, laser beam phase space distribution is adjusted by using a variable optical path to realize beam shaping, a laser beam can be changed into a rectangular flat-topped light spot, and the size of the rectangular light spot is adjusted through the size of the optical path. And the focal length of the laser beam and the size of the flat-topped light spot can be dynamically adjusted, and uniform machining on microelectronic device packaging, wafer surfaces and optical element surfaces is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser precision machining, and in particular to a laser precision machining device and method based on dynamic adjustment of beam shaping based on light field imaging. Background Art

[0002] Current beam shaping technology plays a key role in the field of laser precision processing, providing core support for various high-precision manufacturing applications. Especially in precision processing applications such as laser debonding, laser lift-off, laser annealing, laser cutting, laser grooving, and laser precision coating removal, optimization of uniformly distributed beam shape is a key factor in ensuring processing quality. Traditional laser processing systems rely on Gaussian or flat-top beams to achieve material processing, but these methods are often limited by insufficient beam uniformity, limited dynamic adjustment capabilities, and uneven energy distribution. Especially in large-area processing scenarios, traditional fixed beam shaping systems find it difficult to achieve uniform energy density across the entire processing plane, resulting in insufficient processing of edge areas or excessive processing of the center area.

[0003] Most existing beam shaping solutions use static optical elements to pre-shape the beam. However, these methods struggle to adjust parameters such as beam size in real time to meet optimal processing conditions when faced with varying material properties, processing shapes, and environmental changes. Furthermore, the accumulation of optical aberrations during long-distance beam transmission can significantly affect the uniformity of the processing area, a problem that is particularly prominent in large-field-of-view processing scenarios. In laser debonding, laser lift-off, laser annealing, laser cutting, laser grooving, and laser precision coating removal processes, insufficient beam uniformity can lead to uneven processing areas, impacting product yield.

[0004] The light field imaging dynamic adjustment beam shaping system can change the optical path in real time during the processing process through the dynamic focusing unit. By changing the spatial phase distribution of the laser beam through the optical path, the size of the flat-top rectangular spot can be adjusted to ensure that the spot is evenly distributed on the processing plane. Traditional laser debonding, laser peeling, laser annealing, laser cutting, laser grooving, and laser precision coating removal processing systems have a short optical path and cannot flexibly change the size of the laser flat-top spot. At the same time, they cannot compensate for optical path deviations caused by temperature changes or mechanical vibrations. Therefore, a laser precision processing device and method that can combine light field imaging and dynamic beam shaping technology to solve the shortcomings of existing technologies in beam uniformity, dynamic adaptability, and processing accuracy has become a key point in technological development. Summary of the Invention

[0005] The purpose of the present invention is to provide a laser precision processing device and method based on light field imaging to dynamically adjust beam shaping. The device can achieve the output of a flat-top rectangular light spot evenly distributed on a large-scale plane. By innovatively introducing a variable optical path beam shaping system, it ensures high uniformity and precision processing without energy density gradient when processing large-area planar materials with a maximum size of 400mm×400mm.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a laser precision processing device for dynamically adjusting beam shaping based on light field imaging, comprising a laser emitting unit, an X-axis movable laser reflector, an XY-axis movable laser reflector, a dynamic shaping module and a focusing galvanometer system, wherein the laser emitting unit, the X-axis movable laser reflector, the XY-axis movable laser reflector, the dynamic shaping module and the focusing galvanometer system are all fixed on a bracket on the top of a support platform, a real-time monitoring unit is fixed to the bottom of the focusing galvanometer system, and an object platform is provided on the top of the support platform.

[0007] Preferably, the real-time monitoring unit consists of a CCD camera and a rangefinder.

[0008] A laser precision machining method for dynamically adjusting beam shaping based on light field imaging comprises the following steps:

[0009] S1. Place the workpiece accurately on the workbench and ensure that it is fixed and stable. Then start the device to activate the entire laser precision machining system based on dynamic adjustment of beam shaping based on light field imaging.

[0010] S2. The laser emitting unit generates laser beams of different pulse widths and wavelengths. The laser beams first pass through the X-axis movable laser reflector and the XY-axis movable laser reflector to adjust the incident angle, propagation path, and optical path of the laser beams;

[0011] S3, through the dynamic shaping module, using laser lenses combined with advanced optical control technology, dynamically and finely adjust the magnification according to processing requirements to ensure the stability and uniformity of the beam, adjust the size of the flat-top rectangular spot to make it evenly distributed, and combine with the focusing galvanometer system to shape the beam;

[0012] S4. The adjusted laser beam is dynamically focused by the focusing galvanometer system on the workpiece surface on a large plane up to 400mm×400mm, and begins high-precision laser processing such as laser debonding, laser lift-off, laser annealing, laser cutting, laser grooving, and laser precision coating removal.

[0013] S5. During the processing, the processing is monitored in all directions by a real-time monitoring unit, including the position of the laser focus and the size of the laser spot. Closed-loop control is achieved through a feedback system. When it is detected that the laser focus is misaligned with the workpiece surface, the adaptive adjustment control system automatically adjusts the laser parameters of the laser emitting unit according to the feedback signal, controls the laser incident angle and orientation as well as the laser focus position, and dynamically adjusts the workpiece posture on the object platform so that the laser beam always enters the various areas of the workpiece to be processed at the optimal angle. Once the processing task is completed, the entire complex curved surface multi-axis laser precision processing system stops working, which includes shutting down the laser emitting unit, stopping the operation of each device, and shutting down the monitoring system. Subsequently, the workpiece being processed can be inspected.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. This laser precision processing device, which dynamically adjusts beam shaping based on light field imaging, achieves beam shaping by adjusting the spatial distribution of the laser beam phase using a specially designed laser with a variable optical path. The laser beam can be converted into a rectangular flat-top spot, and the size of the rectangular spot can be adjusted by adjusting the optical path length. The device is equipped with a laser reflector group and a dynamic focusing control system, which can dynamically adjust the focal length of the laser beam and the size of the flat-top spot, achieving uniform processing on the surfaces of microelectronic device packages, semiconductor wafers, and optical components. In combination with a high-precision CCD camera for real-time monitoring and an automatic position correction system, it ensures high precision and high repeatability of the processing process.

[0016] 2. This laser precision processing device, which dynamically adjusts beam shaping based on light field imaging, has a flexible design and is easy to adjust. It is suitable for precise laser processing scenarios of various materials, especially in precision processing fields such as laser debonding, laser lift-off, laser annealing, laser cutting, laser grooving, and laser precision coating removal. The invention provides an innovative solution for upgrading semiconductor packaging processes and precision optical manufacturing, and has broad market prospects and technological leadership. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a left-side perspective structural diagram of the present invention;

[0018] Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention from the right side;

[0019] Figure 3 It is a schematic diagram of the top structure of the present invention.

[0020] In the figure: 1. Laser emitting unit; 2. X-axis movable laser reflector; 3. XY-axis movable laser reflector; 4. Dynamic shaping module; 5. Focusing galvanometer system; 6. Real-time monitoring unit; 7. Object platform. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0022] See also Figure 1-Figure 3 The present invention provides a technical solution: a laser precision processing device for dynamically adjusting beam shaping based on light field imaging, comprising a laser emitting unit 1, an X-axis movable laser reflector 2, an XY-axis movable laser reflector 3, a dynamic shaping module 4 and a focusing galvanometer system 5. The laser emitting unit 1, the X-axis movable laser reflector 2, the XY-axis movable laser reflector 3, the dynamic shaping module 4 and the focusing galvanometer system 5 are all fixed on a bracket on the top of a support platform.

[0023] The laser emitting unit 1 can generate femtosecond, nanosecond, and picosecond laser beams of different wavelengths with specific powers, and perform precision machining on the workpiece surface through the entire dynamically adjusted beam shaping laser precision machining device.

[0024] The X-axis movable laser reflector 2 and the XY-axis movable laser reflector 3 can accurately adjust the propagation path and laser propagation optical path of the laser beam, adjust the phase spatial distribution of the laser beam, and then change the spot size to achieve beam shaping.

[0025] The dynamic shaping module 4 uses a laser lens combined with advanced optical control technology. Through the synergy of variable optical path design and beam shaping elements, it breaks through the limitations of spot shape and energy distribution in traditional laser processing. This module can adjust the spatial distribution and energy density of the laser beam in real time to achieve precise control of the processing process. By changing the optical path length of the laser beam and adjusting its spatial phase distribution, the incident laser is shaped into a flat-top rectangular spot, ensuring uniform energy distribution, avoiding the edge overheating problem of traditional Gaussian spot, and ensuring processing consistency.

[0026] The focusing galvanometer system 5 realizes dynamic focusing and adjusts the laser focus position in real time during the processing process, realizing real-time adjustment of the laser beam focus position, and providing core technical support for high-precision and high-efficiency laser processing.

[0027] A real-time monitoring unit 6 is fixed to the bottom of the focusing galvanometer system 5, and an object platform 7 is provided on the top of the support table. The object platform 7 undertakes the important functions of carrying the workpiece and realizing precise positioning and motion control. This object platform 7 adopts advanced mechanical design and motion control technology, and has the characteristics of high precision, high speed and high stability, which can meet the needs of various laser processing tasks.

[0028] In this embodiment, Figure 1 、 Figure 2 and Figure 3 As shown, the real-time monitoring unit 6 is composed of a CCD camera 601 and a rangefinder 602. Through the coordinated work of the CCD camera 601 and the rangefinder 602, the real-time monitoring unit 6 realizes real-time monitoring of the processing process and the distance between the laser focus and the processed surface, as well as monitoring the status of the workpiece and the laser spot during laser processing, realizing the recording of all parameters of the processing process and supporting process playback and quality traceability.

[0029] According to another aspect of the present invention, a laser precision machining method for dynamically adjusting beam shaping based on light field imaging is provided, comprising the following steps:

[0030] S1. Place the workpiece accurately on the workbench and ensure that it is fixed and stable. Then start the device to activate the entire laser precision machining system based on dynamic adjustment of beam shaping based on light field imaging.

[0031] S2. The laser emitting unit 1 generates a laser beam with specific parameters. The laser beam first passes through the X-axis movable laser reflector 2 and the XY-axis movable laser reflector 3 to adjust the incident angle, propagation path, and optical path of the laser beam;

[0032] S3: Dynamic shaping module 4 uses laser lenses combined with advanced optical control technology to dynamically and finely adjust the magnification according to processing requirements to ensure the stability and uniformity of the beam, adjust the size of the flat-top rectangular spot to make it evenly distributed, and combine with the focusing galvanometer system 5 to shape the beam;

[0033] S4. The adjusted laser beam is dynamically focused by the focusing galvanometer system 5 on the workpiece surface on a large plane area of ​​up to 400mm×400mm, and begins high-precision laser processing such as laser debonding, laser lift-off, laser annealing, laser cutting, laser grooving, and laser precision coating removal.

[0034] S5. During the processing, the processing is monitored in all directions by the real-time monitoring unit 6, including the position of the laser focus and the size of the laser spot. Closed-loop control is achieved through the feedback system. When it is detected that the laser focus is misaligned with the workpiece surface, the adaptive adjustment control system automatically adjusts the laser parameters of the laser emitting unit 1 according to the feedback signal, controls the laser incident angle and orientation as well as the laser focus position, and the object platform 7 dynamically adjusts the workpiece posture so that the laser beam always enters the various areas of the workpiece to be processed at the optimal angle. Once the processing task is completed, the entire complex curved surface multi-axis laser precision processing system stops working, which includes shutting down the laser emitting unit 1, stopping the operation of each device, and shutting down the monitoring system. Subsequently, the processed workpiece can be inspected.

[0035] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A laser precision machining device for dynamically adjusting beam shaping based on light field imaging, comprising a laser emitting unit (1), an X-axis movable laser reflector (2), an XY-axis movable laser reflector (3), a dynamic shaping module (4) and a focusing galvanometer system (5), characterized in that: The laser emitting unit (1), the X-axis movable laser reflector (2), the XY-axis movable laser reflector (3), the dynamic shaping module (4) and the focusing galvanometer system (5) are all fixed on a bracket on the top of the support platform; a real-time monitoring unit (6) is fixed to the bottom of the focusing galvanometer system (5); and an object platform (7) is provided on the top of the support platform.

2. The laser precision machining device for dynamically adjusting beam shaping based on light field imaging according to claim 1, characterized in that: The real-time monitoring unit (6) is composed of a CCD camera (601) and a rangefinder (602).

3. A laser precision machining method for dynamically adjusting beam shaping based on light field imaging, applied to a laser precision machining device for dynamically adjusting beam shaping based on light field imaging according to any one of claims 1-2, characterized in that: The following steps are involved: S1. Place the workpiece accurately on the workbench and ensure that it is fixed and stable. Then start the device to activate the entire laser precision machining system based on dynamic adjustment of beam shaping based on light field imaging. S2, the laser emitting unit (1) generates laser beams of different wavelengths, and the laser beams first pass through the X-axis movable laser reflector (2) and the XY-axis movable laser reflector (3) to adjust the incident angle, propagation path, and optical path of the laser beams; S3, through the dynamic shaping module (4), using the laser lens combined with advanced optical control technology, the magnification is finely adjusted dynamically according to the processing requirements to ensure the stability and uniformity of the light beam, adjust the size of the flat-top rectangular spot to make it evenly distributed, and combine with the focusing galvanometer system (5) to shape the light beam; S4, the adjusted laser beam is dynamically focused by the focusing galvanometer system (5) on the workpiece surface on a large plane area of ​​up to 400mm×400mm, and starts high-precision laser debonding, laser peeling, laser annealing, laser cutting, laser grooving and laser precision coating removal. S5. During the processing, the processing is monitored in all directions by the real-time monitoring unit (6), including the position of the laser focus and the size of the laser spot. Closed-loop control is achieved through the feedback system. When it is detected that the laser focus is misaligned with the workpiece surface, the adaptive adjustment control system automatically adjusts the laser parameters of the laser emitting unit (1) according to the feedback signal, controls the laser incident angle and orientation and the laser focus position, and the object platform (7) dynamically adjusts the workpiece posture so that the laser beam always enters the various areas of the workpiece to be processed at the optimal angle. Once the processing task is completed, the entire complex curved surface multi-axis laser precision processing system stops working, which includes shutting down the laser emitting unit (1), stopping the work of each device, and shutting down the monitoring system. Subsequently, the workpiece being processed can be inspected.

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