WO2017135543A1

WO2017135543A1 - Laser processing method using inclination angle of laser beam

Info

Publication number: WO2017135543A1
Application number: PCT/KR2016/010233
Authority: WO
Inventors: 김병철; 이정용; 장의순; 공태원
Original assignee: (주)이오테크닉스
Priority date: 2016-02-05
Filing date: 2016-09-12
Publication date: 2017-08-10
Also published as: KR101789185B1; TWI636844B; KR20170093509A; TW201728393A

Abstract

Disclosed is a laser processing method using the inclination angle of a laser beam. The disclosed laser processing method is to remove an edge portion of a workpiece loaded on a stage by irradiating the laser beam to the edge portion. The method comprises the steps of: passing the laser beam through a focusing lens; and irradiating the edge of the workpiece with a tilted beam including an outer surface inclined with respect to the central axis of the focusing lens among the laser beams having passed through the focusing lens. The edge portion of the workpiece is processed to be oblique so as to correspond to the outer surface of the inclined beam.

Description

Laser processing method using the tilt angle of the laser beam

The present invention relates to a laser processing method using the inclination angle of the laser beam, and more particularly, to a laser processing method for processing the object by using the inclination angle of the laser beam passing through the focusing lens.

The laser processing apparatus irradiates a laser beam emitted from a laser light source to an object by using an optical system, and marking, exposure, etching, and punching (processing) of the object by the irradiation of the laser beam. Machining operations such as punching, scribing, dicing and the like are performed.

When processing the workpiece, a telecentric lens is mainly used to make the cutting plane vertical. In this case, since the laser beam is vertically incident on the surface of the object to be processed, the cutting is made vertically, and since the laser beam is vertically incident, damage to the lower material may occur when only the upper member is to be processed in the laminated member.

In addition, in the case of forming a trench in a workpiece, since the intensity of the laser beam is usually a Gaussian beam, an area that is optically out of the depth of field (DOF) is formed. Inclination may occur in the cut surface when machining the object having the thickness present. The inclination of the cut surface may cause problems due to dimensions in a process such as assembly later.

One embodiment of the present invention provides a laser processing method capable of removing only the edge portion of the upper member from the object to be formed in a stacked form.

In addition, an embodiment of the present invention provides a laser processing method capable of processing the cut surface perpendicular to the stage when the trench processing on the object to be processed.

According to an aspect of the present invention, there is provided a laser processing method including: irradiating a laser beam to an edge portion of an object to be loaded on a stage to remove the edge portion, the laser processing method comprising: passing the laser beam through a focusing lens; And irradiating an edge of the object to be processed with an inclined beam including an outer surface which is inclined with respect to a central axis of the focusing lens among the laser beams passing through the focusing lens. It is processed to be inclined in correspondence with the outer surface of the inclined beam.

According to the embodiment of the present invention, by using the inclined beam generated by passing the laser beam through the focusing lens, the lower member in the laminated member can remove only the edge portion of the upper member without damaging it.

In addition, by adjusting the angle of incidence of the laser beam incident on the focusing lens, the trench may be vertically processed with respect to the stage when trenching the workpiece.

Figure 1 schematically shows a laser processing apparatus according to an embodiment of the present invention.

2A and 2B schematically illustrate a process of processing an object by using a laser beam passing through a telecentric lens in the object in which the glass substrate and the film layer are sequentially stacked.

3A schematically illustrates a first tilt beam and a second tilt beam generated by passing a laser beam through a focusing lens.

3b and 3c schematically show a state in which only the edge portion of the film layer is processed by using an inclined beam in a processing object in which the glass substrate and the film layer are sequentially stacked.

4A and 4B schematically illustrate a process of processing a workpiece by using a laser beam passing through a telecentric lens in a workpiece having a flexible printed circuit board, a printed circuit board, and a mold layer sequentially stacked. It is shown as.

5A and 5B schematically illustrate a process of processing only an edge portion of a printed circuit board using an inclined beam in a process object in which a flexible printed circuit board, a printed circuit board, and a mold layer are sequentially stacked.

6A and 6B schematically illustrate the formation of a trench in a workpiece by using a laser beam passing through a focusing lens.

7A to 7C schematically illustrate a process of forming a trench in an object by obliquely injecting a laser beam into a focusing lens.

The focusing lens may include an F-theta lens.

The object to be processed may include first and second members sequentially stacked on the stage.

The second member may be provided to cover the first member, and the second member may have a size larger than that of the first member.

The inclined beam may be irradiated to an edge portion of the second member.

The first member may not be exposed to the laser beam passing through the focusing lens.

The first and second members may include a glass substrate and a film layer attached to the glass substrate.

The first and second members may include a flexible printed circuit board (FPCB) and a printed circuit board provided on the flexible printed circuit board.

The output of the laser beam may be 1W ~ 4W.

The stage may move in a direction horizontal or perpendicular to the surface of the workpiece.

In a laser processing method according to an embodiment of the present invention, in a laser processing method of forming a trench by irradiating a laser beam to a workpiece loaded on a stage, the laser beam is directed from a central axis of the focusing lens in a first direction. Incident inclinedly; Forming a first inclined beam including a first vertical plane formed by the laser beam perpendicular to the object to be processed by passing through the focusing lens; Irradiating the first oblique beam onto the object to form a portion of the trench; Inclining the laser beam in a second direction from a central axis of the focusing lens; Forming a second inclined beam including a second vertical surface formed perpendicularly to the object by passing the laser beam through the focusing lens; And completing the trench by irradiating the second oblique beam to the object to be processed.

The second direction may be opposite to the first direction.

The trench may include a first trench surface corresponding to the first vertical plane of the first sloped beam and a second trench surface corresponding to the second vertical plane of the second sloped beam.

The first and second directions may be inclined 5 ° to 10 ° with respect to the central axis of the focusing lens.

The focusing lens may include an F-theta lens.

The object to be processed may include a substrate and a mold layer stacked on the substrate, and the trench may be formed in the mold layer.

The stage may move in a horizontal or vertical direction with respect to the surface of the workpiece.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "electrically connected" with another element in between. . In addition, when a part is said to "include" a certain component, which means that it may further include other components, except to exclude other components unless otherwise stated.

1 schematically shows a laser processing apparatus 100 according to an embodiment of the present invention.

Referring to FIG. 1, the laser processing apparatus 100 processes the workpiece W loaded on the stage S using the laser beam L. FIG. The laser processing apparatus 100 includes a laser light source 110, a beam delivery system 120, a scanner 130, and a focusing lens 140.

The laser light source 110 refers to a means for emitting the laser beam (L), the laser light source 110 is a gas, a liquid, a solid laser light source according to the type of material generating the laser beam (L) Can be classified. In addition, the laser light source 110 may emit, for example, a pulsed laser beam, but is not limited thereto, and may emit a continuous wave laser beam according to the type of processing operation. In addition, the output of the laser beam (L) emitted by the laser light source 110 may be about 1W ~ 4W.

The beam delivery system 120 transmits the laser beam L emitted from the laser light source 110 along a predetermined path, and may include, for example, a plurality of mirrors or an optical cable. .

The scanner 130 performs a predetermined machining operation on the object to be processed by scanning the laser beam L on the object to be processed. For example, a 2D galvanometer for scanning the laser beam L in the x-axis and y-axis directions parallel to and perpendicular to the surface of the workpiece W may be used. The 2D galvanometer can improve the precision of the laser processing operation by finely controlling the scan point of the laser beam (L). The scanner 130 may position the laser beam L in the processing area and control the linear motion of the laser beam L. FIG. In addition, the scanner 130 may adjust an incident angle of the laser beam L incident on the focusing lens 140.

In order to perform a predetermined machining operation on the workpiece W, the stage S may also move in the x-axis and y-axis directions. Not only the scan of the laser beam L by the scanner 130 but also the movement of the stage S may be performed on a wider range of areas. In addition, the scanner 130 may perform a machining operation on the workpiece W while the workpiece W is moved by the stage S. FIG. In this case, a position tracking unit (not shown) may be connected to the scanner 130 and the stage S, and the position tracking unit tracks the position of the workpiece W loaded on the stage S and the scanner 130. Position information of the object (W) can be transmitted to.

A focusing lens 140 may be provided between the scanner 130 and the workpiece W. The focusing lens 140 may serve to adjust the focus of the laser beam L so that the laser beam L passing through the scanner 130 may be focused at a desired position of the processing object W. In addition, the focusing lens 140 may include an F-theta lens.

2A and 2B illustrate a process of processing an object W using a laser beam La passing through a telecentric lens in the object W in which a glass substrate and a film layer are sequentially stacked. It is a schematic illustration.

Referring to FIG. 2A, in the case of a device such as a liquid crystal display (LCD) or an organic light emitting diode (OLED), the film layer 220 may be attached to the glass substrate 210. Can be. The film layer 220 may include a polarizing plate or the like. The film layer 220 may be provided to cover the glass substrate 210, and the film layer 220 may have a larger size than the glass substrate 210. Therefore, the edge portion of the film layer 220 may be exposed to the outer portion of the glass substrate 210 surface, the edge portion of the exposed film layer 220 may need to be cut. The laser beam La passing through the telecentric lens may be incident on the edge portion of the film layer 220 exposed to the outer portion of the surface of the glass substrate 210.

2A and 2B, after the laser beam La is incident on the edge portion of the film layer 220 exposed to the outer portion of the glass substrate 210 surface, the laser beam La is driven by driving the scanner (130 of FIG. 1). The edge portion of the film layer 220 may be cut by moving the laser beam La in the y-axis direction or moving the stage S in the y-axis direction. However, since the laser beam La is incident perpendicularly to the surface of the film layer 220, the laser beam La may also be incident on the glass substrate 210, thereby causing damage regions (eg, damage) on the glass substrate 210. D) may occur.

FIG. 3A schematically illustrates tilted beams L1 and L2 generated by passing the laser beam L through the focusing lens 140.

Referring to FIG. 3A, the laser beam L emitted from the scanner 130 of FIG. 1 is incident on the focusing lens 140. When the laser beam L passes through the focusing lens 140, the inclined beams L1 and L2 including an outer surface inclined with respect to the central axis A of the focusing lens 140 may be emitted. The inclination angle θ _{1 in} which the inclination beams L1 and L2 are inclined with respect to the central axis A of the focusing lens 140 may be about 5 ° to 10 °.

3B and 3C illustrate a process in which only the edge portion of the film layer 230 is processed using the inclined beam L1 in the processing target W in which the glass substrate 210 and the film layer 230 are sequentially stacked. It is shown schematically.

3B and 3C, the inclined beam focused by the focusing lens 140 (FIG. 3A) to cut the edge portion of the film layer 230 exposed to the outer portion of the glass substrate 210 surface ( One of the oblique beams L1 of L1 and L2 may be irradiated to the edge portion of the film layer 230. After the inclined beam L1 is incident on the edge portion of the film layer 230, the y-axis of the stage S or the movement in the y-axis direction of the inclined beam L1 driven by the scanner 130 (FIG. 1) is driven. The edge portion of the film layer 220 may be cut by moving in the direction. The cut surface of the cut film layer 230 may be inclined to correspond to the inclined outer surface of the inclined beam (L1).

Since the inclined beam L1 is inclined by a predetermined inclination angle θ ₁ with respect to the central axis A of the focusing lens 140, the glass substrate 210 may not be exposed to the inclined beam L1. Therefore, when the film layer 230 is cut by the inclined beam L1, the glass substrate 210 may not be damaged.

On the other hand, when the precision of the equipment is low, even after the inclination beam L1 is irradiated onto the glass substrate 210 after cutting the edge of the film layer 230, the size of the laser beam due to the inclination angle of the inclination beam L1 As the size increases, damage to the glass substrate 210 may be prevented. The output of the laser beam L may be about 1W to 4W. The laser beam L having an output in this range can cut the edge portion of the film layer 230 and does not damage the glass substrate 210 even when the inclined beam L1 is irradiated onto the glass substrate 210. You may not.

In addition, in order to irradiate the oblique beam L1 to the film layer 230, the stage S may move in a direction perpendicular to the surface of the object W, that is, the surface of the film layer 230, that is, in the z-axis direction. .

4A and 4B illustrate a laser passing through a telecentric lens in a workpiece W in which a flexible printed circuit board 310, a printed circuit board 320, and a mold layer 330 are sequentially stacked. It schematically shows a state of processing the object to be processed (W) using the beam (La).

Referring to FIG. 4A, a printed circuit board 320 and a mold layer 330 may be sequentially provided on the flexible printed circuit board 310. Due to the flexibility of the flexible printed circuit board 310, the edge portion of the printed circuit board 320 may need to be cut. The laser beam La passing through the telecentric lens may be incident on an edge portion of the printed circuit board 320.

4A and 4B, after the laser beam La is incident on the edge portion of the printed circuit board 320, the laser beam La is moved in the y-axis direction of the laser beam La by driving the scanner (130 of FIG. 1). The edge portion of the printed circuit board 320 may be cut by moving or moving in the y-axis direction of the stage S. FIG. However, since the laser beam La is incident perpendicularly to the surface of the printed circuit board 320, the laser beam La may also be incident on the flexible printed circuit board 310, thereby causing the flexible printed circuit board 310. Damaged areas D may occur on the image.

5A and 5B illustrate a printed circuit board using an inclined beam L1 in a workpiece W in which a flexible printed circuit board 310, a printed circuit board 340, and a mold layer 330 are sequentially stacked. It schematically shows how to process only the edge portion of the 340.

5A and 5B, one of the inclined beams (L1 and L2 in FIG. 3A) focused by the focusing lens (140 in FIG. 3A) to cut the edge portion of the printed circuit board 340. L1 may be irradiated to the edge portion of the printed circuit board 340. After the inclined beam L1 is incident on the edge portion of the printed circuit board 340, the inclination beam L1 is moved in the y-axis direction by the driving of the scanner (130 in FIG. 1) or in the y-axis direction of the stage. By moving the edge portion of the printed circuit board 340 may be cut. The cut surface of the cut printed circuit board 340 may be inclined to correspond to the inclined outer surface of the inclined beam (L1).

Since the inclined beam L1 is inclined by a predetermined inclination angle (θ _{1 in} FIG. 3A) with respect to the central axis (A in FIG. 3A) of the focusing lens 140 of FIG. 3A, the flexible printed circuit board 310 may be inclined beam ( May not be exposed to L1). Therefore, when the printed circuit board 340 is cut by the inclined beam L1, the flexible printed circuit board 310 may not be damaged.

On the other hand, when the precision of the equipment is low, even after the inclination beam L1 is irradiated to the flexible printed circuit board 310 after cutting the edge of the printed circuit board 340, due to the inclination angle of the inclination beam L1 Damage to the flexible printed circuit board 310 may be prevented by increasing the size of the beam. The output of the laser beam L may be about 1W to 4W. The laser beam L having an output in this range can cut an edge portion of the printed circuit board 340, and the flexible printed circuit board even when the inclined beam L1 is irradiated to the flexible printed circuit board 310 310 may not be damaged.

Also, in order to irradiate the inclined beam L1 to the printed circuit board 340, the stage may move in a direction perpendicular to the surface of the object W, that is, the surface of the printed circuit board 340, that is, in the z-axis direction.

6A and 6B schematically illustrate the formation of a trench in a workpiece by using a laser beam passing through the focusing lens 140.

6A and 6B, a substrate 410 and a mold layer 420 sequentially stacked on the stage S are provided, and the laser beam L emitted from the scanner 130 of FIG. 1 is focused. Pass through the lens 140. When the laser beam L passes through the focusing lens 140, an inclined beam Lb including an outer surface inclined with respect to the central axis A of the focusing lens 140 may be emitted.

After irradiating the inclined beam Lb to the mold layer 420 provided on the substrate 410, the stage S moves or moves in the y-axis direction of the inclined beam Lb by driving the scanner 130 (FIG. 1). The trench may be formed in the mold layer 420 by moving in the y-axis direction. The outer surface of the trench formed by the inclined beam Lb may not be perpendicular to the surface of the substrate 410 and may have an inclination angle. After the trench is formed in the mold layer 420, the trench may be coated with a conductive material or a conductive coating may be formed through sputtering, and in some cases, the outer surface of the processed trench may be perpendicular to the surface of the substrate 410. There is a need.

7A to 7C schematically illustrate a process of forming a trench in the workpiece W by inclining the laser beam L into the focusing lens 140.

Referring to FIG. 7A, a substrate 410 and a mold layer 430 sequentially stacked on the stage S are provided.

Referring to FIG. 7B, the laser beam L is inclined in the first direction from the central axis A of the focusing lens 140 by driving the scanner 130 (see FIG. 1). The first direction may be a positive direction of the x-axis, and the inclination angle θ ₂ formed by the obliquely incident laser beam L with the central axis A may be 5 ° to 10 °.

When the laser beam L passes through the focusing lens 140, a first oblique beam L ′ including a first vertical plane formed perpendicular to the surface of the mold layer 430 may be formed. After irradiating the first tilted beam L 'to the mold layer 430 provided on the substrate 410, the first tilted beam L' is driven in the y-axis direction by the driving of the scanner (130 of FIG. 1). The trench may be formed in the mold layer 430 by moving or moving in the y-axis direction of the stage S. FIG. The surface processed in the mold layer 430a may be the first trench surface 435. The first trench surface 435 may be formed to correspond to the first vertical surface of the first inclined beam L ', and the first trench surface 435 may be perpendicular to the surface of the substrate 410.

Referring to FIG. 7C, the laser beam L is inclined in the second direction from the central axis A of the focusing lens 140 by driving the scanner 130 (see FIG. 1). The second direction may be opposite to the first direction, and the second direction may be a negative direction of the x-axis. In addition, the inclination angle θ _{2 of the} obliquely incident laser beam L and the central axis A may be 5 ° to 10 °.

When the laser beam L passes through the focusing lens 140, a second oblique beam L ″ including a second vertical plane formed perpendicular to the surface of the mold layer 430 may be formed. After irradiating the second oblique beam L ″ to the mold layer 430 provided on the substrate 410, the second oblique beam L ″ is driven in the y-axis direction by the driving of the scanner 130 (FIG. 1). The trench may be formed in the mold layer 430 by moving or moving in the y-axis direction of the stage S. FIG. The surface processed in the mold layer 430b may be the second trench surface 436. The second trench surface 436 may be formed to correspond to the second vertical plane of the second oblique beam L ″, and the second trench surface 436 may be perpendicular to the surface of the substrate 410.

In the laser processing method using the inclination angle of the laser beam according to the above embodiment, by using the inclined beam generated by passing the laser beam through the focusing lens, the lower member of the laminated member can be removed without damaging the edge of the upper member. have. In addition, by adjusting the angle of incidence of the laser beam incident on the focusing lens, the trench may be vertically processed with respect to the stage when trenching the workpiece.

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

Claims

In the laser processing method for removing the edge portion by irradiating a laser beam to the edge portion of the object to be loaded on the stage,

Passing the laser beam through a focusing lens; And

And irradiating an edge of the object to be processed with an inclined beam including an outer surface inclined with respect to a central axis of the focusing lens among the laser beams passing through the focusing lens.

The edge portion of the object to be processed is laser processing is inclined corresponding to the outer surface of the inclined beam.
The method of claim 1,

The focusing lens is laser processing method comprising an F-theta lens.
The method of claim 1,

The object to be processed includes a laser processing method including first and second members sequentially stacked on the stage.
The method of claim 3, wherein

And the second member is provided to cover the first member, and the second member has a larger size than the first member.
The method of claim 4, wherein

And the inclined beam is irradiated to an edge portion of the second member.
The method of claim 5,

And the first member is not exposed to the laser beam passing through the focusing lens.
The method of claim 3, wherein

And the first and second members comprise a glass substrate and a film layer attached to the glass substrate.
The method of claim 3, wherein

The first and second members include a flexible printed circuit board (FPCB) and a printed circuit board provided on the flexible printed circuit board.
The method of claim 1,

Laser processing method of the output of the laser beam is 1W ~ 4W.
The method of claim 1,

And the stage moves in a direction horizontal or perpendicular to the surface of the workpiece.
In the laser processing method of forming a trench by irradiating a laser beam to the object to be loaded on the stage,

Inclining the laser beam in a first direction from a central axis of the focusing lens;

Forming a first inclined beam including a first vertical plane formed by the laser beam perpendicular to the object to be processed by passing through the focusing lens;

Irradiating the first oblique beam onto the object to form a portion of the trench;

Inclining the laser beam in a second direction from a central axis of the focusing lens;

Forming a second inclined beam including a second vertical surface formed perpendicularly to the object by passing the laser beam through the focusing lens; And

And irradiating the second oblique beam to the object to complete the trench.
The method of claim 11,

And said second direction is a direction opposite to said first direction.
The method of claim 12,

And the trench includes a first trench surface corresponding to a first vertical plane of the first sloped beam and a second trench surface corresponding to a second vertical plane of the second sloped beam.
The method of claim 11,

The first and second directions are laser processing method inclined 5 ° ~ 10 ° with respect to the central axis of the focusing lens.
The method of claim 11,

The focusing lens is laser processing method comprising an F-theta lens.
The method of claim 11,

The object to be processed includes a substrate and a mold layer laminated on the substrate, and the trench is formed in the mold layer.
The method of claim 11,

And the stage moves in a direction horizontal or perpendicular to the surface of the workpiece.