JP-2026075619-A - Laser processing apparatus and laser processing method using the same, which enable various processing patterns.

Abstract

[Problem] To provide a laser processing apparatus and a laser processing method that include an optical unit configured to realize various processing patterns. [Solution] An optical unit including a first optical group containing multiple first diffractive optical elements that transform the shape of a laser beam in order to realize various processing patterns with a single optical unit, a second optical group containing multiple second diffractive optical elements that split the laser beam into multiple beams, an optical element holder that selects diffractive optical elements from the first optical group and the second optical group respectively, and combines the selected diffractive optical elements by arranging them in series with respect to the optical axis of the laser beam, and a lens unit that focuses the laser beam onto the surface of the workpiece, and a controller that receives processing pattern data, determines processing parameters according to the input processing pattern data, and controls the optical element holder to select a combination of first and second diffractive optical elements corresponding to the determined processing parameters. [Selection Diagram] Figure 1

Inventors

• リー， ジョン ジュン
• リー， ボン ドン

Assignees

• メーレカンパニー インコーポレイテッド

Dates

Publication Date

20260508

Application Date

20251021

Priority Date

20241022

Claims (20)

1. In a laser processing apparatus configured to achieve various processing patterns with a single optical unit, A laser oscillator that generates a laser beam, The laser beam is adjusted, and the adjusted laser beam is irradiated onto the surface of the workpiece. A first optical group including a plurality of first diffractive optical elements that change the shape of the laser beam, A second optical group including multiple second diffractive optical elements that split the aforementioned laser beam into multiple beams, An optical unit including an optical element holder which selects diffractive optical elements from the first optical group and the second optical group, and combines the selected diffractive optical elements by arranging them in series with respect to the optical axis of the laser beam, and a lens unit which focuses the laser beam onto the surface of the workpiece, A processing table for moving the workpiece in the processing direction, A controller that receives processing pattern data, determines processing parameters according to the input processing pattern data, and controls the optical element holder to select a combination of the first diffractive optical element and the second diffractive optical element corresponding to the determined processing parameters, Laser processing equipment, including...
2. The laser processing apparatus according to claim 1, further comprising a laser attenuator for adjusting the output intensity of the laser beam.
3. The first optical group further includes a blank through which the laser beam passes directly, The laser processing apparatus according to claim 1, wherein the plurality of first diffractive optical elements include top-hat diffractive optical elements that convert the laser beam into at least one shape from a line shape, a rectangular shape, and a square shape.
4. The second optical group further includes a blank through which the laser beam passes directly, The laser processing apparatus according to claim 1, wherein the plurality of second diffractive optical elements include multi-spot diffractive optical elements that split the laser beam into multiple beams and realize a different number of multiple beams.
5. The laser processing apparatus according to claim 1, wherein the optical element holder includes a rotary turret or sliding mechanism capable of selectively positioning the diffractive optical elements of the first optical group and the second optical group.
6. The aforementioned lens unit includes a plurality of objective lenses, each with a different magnification. The laser processing apparatus further includes a lens holder that arranges and combines the objective lens selected by the lens unit with the selected diffractive optical element in series with respect to the optical axis, The laser processing apparatus according to claim 1, wherein the controller controls the lens holder to select an objective lens corresponding to the determined processing parameters.
7. The laser processing apparatus according to claim 6, wherein the plurality of objective lenses include an objective lens having at least 5x magnification and an objective lens having 10x magnification.
8. The aforementioned processing pattern data includes the processing line width and processing depth. The laser processing apparatus according to claim 1, wherein the processing parameters include at least the shape of the laser beam and the number of multiple beams.
9. The laser processing apparatus according to claim 1, wherein the controller determines the rotation angle of a first diffractive optical element selected according to the input processing pattern data, and controls the first diffractive optical element to rotate according to the determined rotation angle with respect to a rotation axis parallel to the normal of the plane of the workpiece.
10. The system further includes a beam limiting element disposed between the first optical group and the lens unit, which blocks a portion of the laser beam. The beam limiting element is a slit or aperture. The laser processing apparatus according to claim 9, wherein the controller determines the cutoff range of the laser beam based on the rotation angle and controls the beam limiting element based on the determined cutoff range of the laser beam.
11. The laser processing apparatus according to claim 1, further comprising a camera that acquires real-time video via the same path through which the laser beam is irradiated.
12. In a laser processing method using the laser processing apparatus described in claim 1, a) A step in which processing pattern data is input to the controller and processing parameters are determined, b) The controller controls the combination of the first diffractive optical element and the second diffractive optical element according to the processing parameters. c) A laser processing method comprising the steps of the controller controlling the laser oscillator to output a laser beam and irradiate the surface of a workpiece with the laser beam adjusted via a selected first diffractive optical element and a selected second diffractive optical element, thereby forming a processing pattern on the workpiece.
13. In step a), if first machining pattern data for machining a first machining pattern with a first machining line width and a first machining depth is input to the controller, The laser processing method according to claim 12, wherein in step b), the controller controls the optical element holder to combine a first top-hat diffractive optical element that converts a laser beam into a line beam of a first length as the first diffractive optical element, and a first multi-spot diffractive optical element that splits the line beam into a first number of multiple beams as the second diffractive optical element, and the multiple beams are arranged in parallel in the processing direction.
14. In step a), if second machining pattern data for machining a second machining pattern having a first machining line width and a second machining depth different from the first machining depth is input to the controller, In step b), the controller controls the optical element holder to combine a first top-hat diffractive optical element that converts a laser beam into a line beam of a first length as the first diffractive optical element, and a second multi-spot diffractive optical element that splits the line beam into a second number of multiple beams as the second diffractive optical element, wherein the second number is different from the first number, the laser processing method according to claim 13.
15. In step a), if third machining pattern data for machining a third machining pattern having a second machining line width and a first machining depth different from the first machining line width is input to the controller, In step b), the controller controls the optical element holder so that the first diffractive optical element selects a second top-hat diffractive optical element that converts the laser beam into a line beam of a second length, and the second diffractive optical element selects a first multi-spot diffractive optical element that splits the line beam into a first number of multiple beams, wherein the second length is different from the first length, the laser processing method according to claim 13.
16. In step a), if the controller receives fourth machining pattern data for machining a fourth machining pattern having a third machining line width smaller than the first machining line width and a third machining depth greater than the first machining depth, The laser processing method according to claim 13, wherein in step b), the controller selects a blank in the first optical group through which the laser beam passes directly, and the second diffractive optical element controls the optical element holder to select and combine with a first multi-spot diffractive optical element that splits the line beam into a first number of multiple beams.
17. The lens unit includes multiple objective lenses, each with a different magnification. The aforementioned laser processing apparatus is The lens unit further includes a lens holder that arranges the objective lens selected in the aforementioned lens unit in series with the selected diffractive optical element with respect to the optical axis, The method according to claim 12, further comprising controlling the controller to select an objective lens in accordance with the processing parameters in step b).
18. The laser processing method according to claim 12, further comprising the steps of the controller determining the rotation angle of a first diffractive optical element selected according to input processing pattern data, and controlling the first diffractive optical element to rotate with respect to a rotation axis parallel to the normal of the plane of the workpiece according to the determined rotation angle.
19. The laser processing apparatus further includes a beam limiting element positioned between the first optical group and the lens unit, which blocks a portion of the laser beam. The laser processing method according to claim 18, further comprising the steps of the controller determining a cutoff range of the laser beam based on the rotation angle and controlling the beam limiting element based on the determined cutoff range of the laser beam.
20. The laser processing apparatus further includes a camera that acquires real-time images via the same path through which the laser beam is irradiated. The laser processing method according to claim 12, further comprising the step of the controller confirming the alignment of the first diffractive optical element and the second diffractive optical element in real time.

Description

This invention relates to a laser processing apparatus used for semiconductor or display processing, and a laser processing method using the same. When processing semiconductor substrates or display elements, laser patterning can be performed by selectively removing material from the surface of the workpiece using laser ablation, thereby precisely forming a desired pattern. Furthermore, in semiconductor chip dicing, chip packaging, or display substrate separation processes, laser grooving can be performed to form precise grooves in the workpiece. In laser processing equipment that performs such laser processing, the laser beam pattern irradiated onto the workpiece must change depending on the type of workpiece, the specifications and shape of the processing, and the processing method. Therefore, the type and size of the optical unit included in the laser processing equipment must also change accordingly. However, changing the optical unit according to various processing specifications presents not only technical limitations but also problems such as reduced yield, decreased processing quality, increased processing defects, and cost issues. The configuration of an optical unit is very complex, but changing the multiple elements contained in the optical unit to meet various processing specifications results in aberrations caused by the multiple elements contained in the optical unit, leading to a decrease in processing quality and processing defects, which in turn results in a low yield. Figure 1 shows a laser processing apparatus according to one embodiment of the present invention. Figure 2 shows an optical unit according to one embodiment of the present invention. Figure 3 is a flowchart illustrating the laser processing method using the laser processing apparatus shown in Figure 1. Figure 4 illustrates one embodiment of a laser processing method that achieves various processing patterns using the laser processing apparatus shown in Figure 1. Figure 5 illustrates another embodiment of a laser processing method that uses the laser processing apparatus of Figure 1 to achieve various processing patterns. Figure 6 illustrates another embodiment of a laser processing method that uses the laser processing apparatus shown in Figure 1 to achieve various processing patterns. Figure 7 shows a laser processing apparatus according to another embodiment of the present invention. Figure 8 is a flowchart illustrating the laser processing method using the laser processing apparatus shown in Figure 7. Figure 9 illustrates one embodiment of a laser processing method that realizes various processing patterns using the laser processing apparatus shown in Figure 7. Figure 10 is an image showing the rotation of the laser beam produced by the laser processing apparatus shown in Figure 7. Figure 11 shows a laser processing apparatus according to another embodiment of the present invention. Figure 12 is a flowchart illustrating the laser processing method using the laser processing apparatus shown in Figure 11. Figure 13 illustrates one embodiment of a laser processing method that realizes various processing patterns using the laser processing apparatus shown in Figure 11. Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings, so that those with ordinary skill in the art to which the present invention pertains can easily implement it. However, the present invention can be realized in a variety of different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention in the drawings, parts unrelated to the description have been omitted, and similar parts throughout the specification are denoted by similar reference numerals. In the following embodiments, terms such as "first," "second," etc., are used not in a restrictive sense, but rather to distinguish one component from another. In the following embodiments, a singular expression includes plural expressions unless the context clearly indicates otherwise. In the following embodiments, terms such as "includes" or "has" mean that the features or components described herein are present, and do not preclude the possibility of the addition of one or more other features or components. In the following embodiments, when we say that a part such as a membrane, region, or component is on or above another part, this includes not only cases where it is directly above the other part, but also cases where another membrane, region, or component is interposed between them. In drawings, for illustrative purposes, the size of components may be exaggerated or reduced. For example, the dimensions and thicknesses of each component shown in the drawings are arbitrarily shown for illustrative purposes, and therefore the present invention is not necessarily limited to those shown. In the following embodiments, DR1, DR2, and DR3 are not limited to the three axes on the Cartesian coordinat