KR20080079828A - Laser processing apparatus and method - Google Patents

Abstract

The present invention provides a laser processing apparatus and method for dividing an incident laser beam into at least two or more, and processing a target by moving a stage in a direction opposite to the direction in which the laser beam is irradiated.

The laser processing apparatus of the present invention receives a beam splitting means for dividing a laser beam emitted from the laser generating means into at least two or more, and a beam scanner that receives the laser beam split by the beam splitting means and repeatedly reflects the laser beam to the processing position of the object. And stage transfer means for transferring the stage on which the object is to be seated, at least once, in a direction opposite to the direction in which the laser beam is irradiated, while processing the object, the effect of processing the object multiple times with a laser beam having a low energy. It is possible to ensure a narrow line width and to ensure a high processing speed because a plurality of divided laser beams are irradiated to the object at the same time, by moving the stage in the direction opposite to the direction in which the laser beam is irradiated to the object In addition, the processing speed of the object can be further improved.

Description

Laser Processing Apparatus and Method

1 is a block diagram of a laser processing apparatus according to a first embodiment of the present invention,

FIG. 2 is an exemplary view of the beam scanner shown in FIG. 1;

3A and 3B are a first illustration of the beam splitting means shown in FIG. 1 and a cross sectional view of a split beam;

4A and 4B are a second illustration of the beam splitting means shown in FIG. 1 and a cross sectional view of a split beam;

5A and 5B are a third illustration of the beam splitting means shown in FIG. 1 and a cross sectional view of a split beam;

6A and 6B are a fourth illustration of the beam splitting means shown in FIG. 1 and a sectional view of a split beam;

7 is a view for explaining a concept of object processing using a polygon mirror applied to the present invention,

8 is a view for explaining a concept of overlapping beams when processing an object using a polygon mirror;

9 is a schematic configuration diagram of a laser machining apparatus according to a first embodiment of the present invention when a polygon mirror is applied;

10 is a configuration diagram of a laser processing apparatus to which a polygon mirror having an error correction function is applied;

FIG. 11 is a view for explaining a phenomenon in which energy loss occurs at a corner of a reflective surface of a polygon mirror; FIG.

12A and 12B are diagrams for explaining an energy loss relationship in a polygon mirror according to the incidence of a laser beam;

FIG. 13 is a view for explaining an object processing concept using a polygon mirror when a laser beam is incident to cover a plurality of reflective surfaces of the polygon mirror; FIG.

14 is a configuration diagram of a laser processing apparatus according to a first embodiment of the present invention when AOD is applied;

15 is a view for explaining that by-products are discharged when processing the object using a laser while transporting the object,

16 is a configuration diagram of a laser processing apparatus according to a second embodiment of the present invention;

17 is a detailed configuration diagram of the beam shaping unit shown in FIG. 16;

18 is a view for explaining sublimation of by-products when processing an object using a laser processing apparatus according to a second embodiment of the present invention;

19A to 19D are views for explaining a concept of repeatedly irradiating a laser beam to an object in a general laser processing apparatus;

20 is a schematic configuration diagram of a laser machining apparatus according to a third embodiment of the present invention;

21 is a view for explaining the concept that the object surface is uniformly processed by the laser processing apparatus according to a third embodiment of the present invention;

22 is a schematic configuration diagram of a laser machining apparatus according to a fourth embodiment of the present invention;

23A to 23D are views for explaining an example of processing an object using the laser processing apparatus shown in FIG. 32;

24 is an exemplary diagram of a stage applied to the present invention;

25A to 25D are detailed configuration diagrams of each stage shown in FIG. 24;

26 is an exemplary diagram of a thermoelectric device applied to the present invention;

27 is a configuration diagram of a laser machining apparatus according to a fifth embodiment of the present invention;

28 is a diagram showing a first modification of the laser processing apparatus shown in FIG. 27;

29 is a second modified example of the laser processing device shown in FIG. 27;

30 is a third modified example of the laser processing device shown in FIG. 27;

31 is a flowchart for explaining a laser processing method according to the first embodiment of the present invention;

32 is a flowchart for explaining a laser processing method according to a second embodiment of the present invention;

33 is a flowchart for explaining a laser processing method according to a third embodiment of the present invention;

34 is a flowchart for explaining a laser processing method according to a fourth embodiment of the present invention;

FIG. 35 is a flowchart illustrating an embodiment of an object processing process shown in FIG. 34;

36A and 36B are views for explaining an example in which an object is processed according to the processing described with reference to FIG. 35;

37 is a flowchart for explaining another embodiment of the object processing process shown in FIG. 34;

38A and 38B are views for explaining an example of processing an object according to the processing described in FIG. 37;

39 is a flowchart for explaining the laser processing method according to the fifth embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

101 control unit 103 laser generating means

105: beam splitting means 107: driver

109: input unit 111: output unit

113: storage unit 115: beam scanner

117: optical system 119: object

121: stage 123: stage transfer means

125: error correction means 127: encoder

129 mirror 131 beam forming part

11: rotating shaft 12: reflecting surface

200: actuator 202: error correction mirror

300: high frequency driver 302: AOD

1310: first cylindrical lens 1311: second cylindrical lens

400: mask 500: chamber

502: thermoelectric element 504: heat insulation means

506: humidification means 508: sensor

510: thawing means

The present invention relates to a laser processing apparatus and method, and more particularly, to divide an incident laser beam into at least two or more, and to process the object by moving the stage in a direction opposite to the irradiation direction of the laser beam, A laser processing apparatus and method for increasing efficiency.

In general, manufacturing an article using a variety of materials such as wafers, metals, and plastics requires processing procedures such as cutting, grooving, etc., which are important because they have a significant impact on quality and productivity in subsequent processes. Has meaning.

Recently, a laser has been used for such a processing procedure, and a laser processing method focuses a laser beam in a high ultraviolet region (250 to 360 nm) on the surface of an object, causing heating and chemical action to remove a focused portion. That's how it is.

In recent years, in the semiconductor market, a method of increasing chip yield per wafer has increased the number of chips per wafer by reducing the gap between chips on the wafer. As a result, the industry may require a very narrow wafer processing line width of about 15 mu m. In order to satisfy such narrow linewidth, it is necessary to increase the processing overlap of the laser beam, that is, increase the laser frequency and keep the beam intensity relatively low so as to reduce the breakage of the processing linewidth attention. However, the laser currently in use has a problem in that the power decreases as the frequency of the laser beam increases, thereby improving the processing quality, but there is a problem in that the processing time cannot be guaranteed. In addition, when using a laser beam of a low frequency in order to improve the processing speed, the laser beam is overheated by the object to be processed to increase the line width, which makes fine processing impossible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and there is a technical problem to provide a laser processing apparatus and method capable of improving the processing speed while maintaining the intensity of the laser beam.

According to another aspect of the present invention, before irradiating a laser beam to an object, by dividing the laser beam into at least two or more, the intensity of the divided beam is maintained by increasing the power by the number of divided beams while maintaining the same intensity as the beam before dividing. The efficiency is improved and the stage is moved in the direction opposite to the beam irradiation direction while irradiating the split laser beam, thereby improving the processing speed.

Laser processing apparatus according to a first embodiment of the present invention for achieving the above-described technical problem beam splitting means for dividing the laser beam emitted from the laser generating means into at least two or more; A beam scanner that receives the laser beam split by the beam splitting means and reflects the laser beam to be repeatedly scanned at the processing position of the object; And stage transfer means for transferring the stage on which the object is to be seated, at least once, in a direction opposite to the direction in which the laser beam is irradiated, while processing the object.

A laser machining apparatus according to a second embodiment of the present invention comprises: a plurality of laser generating means for emitting a laser; A plurality of beam splitting means for receiving the respective laser beams emitted from the plurality of laser generating means and splitting them into at least two; A plurality of mirrors for reflecting the laser beam split by each of the beam splitting means to the same position; An actuator installed at each of the plurality of mirrors to adjust an angle and a position of the mirror; A reflection mirror which receives and reflects a laser beam reflected from each of the plurality of mirrors; And an optical system that collects a laser beam reflected from the reflection mirror and irradiates the object.

A laser machining apparatus according to a third embodiment of the present invention comprises: a plurality of laser generating means for emitting a laser; A plurality of beam splitting means for receiving the respective laser beams emitted from the plurality of laser generating means and splitting them into at least two; A plurality of polygon mirrors having a plurality of reflecting surfaces and rotating about a rotation axis, the plurality of polygon mirrors receiving and reflecting laser beams respectively divided by the beam splitters; A plurality of reflection mirrors each reflecting a laser beam reflected from each of the plurality of polygon mirrors; And an optical system that collects a laser beam reflected from the reflection mirror and irradiates the object.

A laser machining apparatus according to a fourth embodiment of the present invention comprises: laser generating means for emitting a laser; A plurality of beam splitting means for receiving the laser beam radiated from the laser generating means and dividing the beam into at least two; A beam splitter for splitting each laser beam split by the beam splitting means into two; A plurality of polygon mirrors each having a plurality of reflective surfaces and rotating around a rotation axis, the plurality of polygon mirrors receiving and reflecting laser beams transmitted or reflected by the beam splitter; A plurality of reflection mirrors each reflecting a laser beam reflected from each of the plurality of polygon mirrors; And an optical system that collects a laser beam reflected from the reflection mirror and irradiates the object.

On the other hand, the laser processing method according to a first embodiment of the present invention comprises the steps of mounting the object on the stage; Setting control parameters according to the type and processing purpose of the object; Driving a beam scanner and driving a stage transport means to transport the stage at a predetermined speed; Emitting a laser beam; Dividing the emitted laser beam into at least two and irradiating the beam scanner with the beam scanner; And irradiating the object with the laser beam reflected from the beam scanner, wherein the stage moves in a direction opposite to the direction in which the laser beam is irradiated.

In addition, the laser processing method according to a second embodiment of the present invention is a method for laser processing an object formed in a multi-layer, comprising: a first step of setting the processing parameters for each layer of the object formed of the multi-layer; A second step of performing laser processing by irradiating at least two divided laser beams according to the processing parameters set for the layer exposed to the processing region of the object; A third step of confirming whether processing has been performed for all layers of the object formed of the multiple layers; And a fourth step of proceeding to the second step when the processing for all layers is not completed as a result of the checking of the third step.

In addition, the laser processing method according to the third embodiment of the present invention is a method for laser processing an object formed in a multi-layer, processing the object formed in the multi-layer by irradiating the object with a laser beam divided into at least two or more Cutting a region; And a second step of healing the processing region of the cut object.

Laser processing method according to a fourth embodiment of the present invention comprises the steps of mounting the object on the stage; Setting control parameters according to the type and processing purpose of the object; Adjusting the tilt and position of the first and second mirrors by the first and second actuators; Driving a reflection mirror; Transferring the stage at a preset speed; A system for emitting a laser beam from each of the plurality of laser generating means; Dividing the laser beams emitted from each of the plurality of laser generating means into at least two and then entering the first and second mirrors, respectively; And irradiating a laser beam incident on the reflective mirror through the first and second mirrors to the object.

According to the present invention, when the laser beam incident to the laser processing apparatus is divided into a plurality, the power can be increased by the number of the divided beams while maintaining the intensity before the divided beams are divided, and the number of the divided beams is increased by the number of the divided beams. It was conceived that it could give an effect of increasing the frequency of. For example, processing an object using a laser beam of 200 kHz and 4 W has the same intensity as a laser beam of 100 kHz and 2 W, and thus, narrowing the line width can be ensured if the object is processed by splitting the laser beam of 100 kHz and 6 W into three parts. . In addition, since the power is 6W, the machining speed can be improved, and the beam overlapping effect of 3 times can be obtained. Likewise, if the object is processed by dividing the laser beam of 100 kHz and 8 W into four parts, the object can be processed at a narrower line width and at a higher speed.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

Laser processing unit with laser beam splitting and stage transport

1 is a configuration diagram of a laser processing apparatus according to a first embodiment of the present invention.

As shown in Fig. 1, the laser processing apparatus according to the first embodiment of the present invention includes a control unit 101 for controlling the overall operation, a laser generating means 103 for outputting a laser beam of a specified aperture, and a laser generating means. Beam splitter 105 for dividing the laser beam emitted from 103 into at least two, a driver 107 for driving the beam scanner 115, an input unit 109 for inputting control parameters and control commands, An output unit 111 for displaying information such as an operation state, a storage unit 113 for data storage, and a laser beam emitted from the beam dividing unit 105 are repeatedly scanned in a straight line in a designated section of the object processing position. The optical system 117 for collecting and irradiating the laser beam reflected by the beam scanner 115, the laser beam reflected from the beam scanner 115, and the stage 121 on which the object 119 is seated while processing the object 119 is lasered. beam Stage feeding means 123 for feeding at least once in the direction opposite to the irradiation direction of the. Here, the optical system 117 may be implemented as a condenser lens.

When the object 119 is processed using the laser processing apparatus, first, the control parameter is set through the input unit 109. The setting process is performed by registering a preset menu according to the type and processing type of the object to be stored. Stored in 113, and can be easily performed by calling the menu.

When the setting of the control parameters is completed, the beam scanner 115 is driven by the driver 107.

The beam scanner 115 may be implemented using a reflector using a galvanometer scanner or a servomotor. More specifically, as shown in FIG. 2, the beam scanner 115 is connected to one or two motors 310 and 330 and a rotation axis of the motors 310 and 330, respectively, to designate angles and directions (left and right or up and down). Mirrors 320 and 340 to repeat the rotation according to.

The laser beam incident from the beam splitter 105 to the second mirror 340 is reflected to the first mirror 320. Subsequently, the laser beam reflected from the first mirror 320 is irradiated to the optical system 117, and the laser beam passing through the optical system 117 is irradiated to the object 119. Here, one or both mirrors 320 and 340 may be used depending on the processing purpose.

In the present embodiment, since the first and second mirrors 320 and 340 rotate at a specified angle and direction, the effect of irradiating the laser beam while moving the laser beam can be obtained, as well as the object 119 by the stage transfer means 123. In addition, because it moves, machining time can be shortened.

Referring back to FIG. 1, after driving the beam scanner 115 by the driver 107, the controller 101 operates the stage transfer means 123 to reverse the direction in which the laser beam is irradiated to the object 119. Direction, and when the laser is emitted by controlling the laser generating means 103, the laser beam is split into at least two by the beam splitting means 105 and is incident to the beam scanner 115.

Thereafter, at least two laser beams reflected by the beam scanner 115 are irradiated perpendicularly to the object 119 through the optical system 117. At this time, since the plurality of beams passing through the optical system 117, the result of irradiating the laser beam to the object 119 a plurality of times can be obtained, and since the plurality of laser beams are incident at the same time, while maintaining the processing speed at the level before the beam splitting narrow Machining is possible with the line width, and the quality after machining can be guaranteed.

3A and 3B are first sectional views of the beam splitting means shown in FIG. 1 and cross-sectional views of the splitting beam, showing a case where the laser beam is divided into two using a prism.

As shown in FIG. 3A, the beam splitting means 105 includes a first mirror 10501 that reflects an incident laser beam, a prism 10502, and a prism 10502 that divides the laser beam reflected from the first mirror into two. A second mirror 10503 that reflects the beam split in two.

Here, the first mirror 10501 serves to inject the laser beam into the prism 10502, and the prism 10502 causes the two beams divided according to their arrangement to be symmetrical. The second mirror 10503 controls the optical axis so that the optical axis of the beam emitted from the prism 10502 is horizontal with the optical axis of the laser beam incident to the first mirror 10501, and the laser reflected from the second mirror 10503 The beam is incident to the beam scanner 115 and irradiated to the object. At this time, of course, the optical axis of the laser beam reflected by the beam scanner 115 should be controlled to be perpendicular to the object.

An example of the laser beam cross section irradiated to the object by such beam splitting means is as shown in FIG. 3B. The spacing between two semicircular laser beams may be changed according to the degree of beam refraction of the prism 10502. In addition, since two laser beams can be irradiated within the same area as the irradiation area of the laser beam before splitting, that is, the number of laser beams irradiated per unit area can be increased, thereby increasing processing efficiency.

4A and 4B are second sectional views of the beam splitting means shown in FIG. 1 and cross-sectional views of the splitting beams, illustrating a case where the laser beam is split into two using the beam splitter.

As shown in Fig. 4A, the beam splitting means 105 is a beam splitter 10511 for dividing the incident laser beam into two, and a polarizer for converting polarization characteristics of the first laser beam reflected from the beam splitter 10511. 10512, a first mirror 10514 for reflecting the second laser beam that has passed through the beam splitter 10511, a second mirror 10515 for reflecting the second laser beam reflected from the first mirror 10514 And a polarizing beam splitter 10513 for reflecting the first laser beam whose polarization characteristic is converted in the polarizer 10512, and transmitting the second laser beam reflected in the second mirror 10515. The first and second laser beams reflected and transmitted at 10513 are irradiated perpendicularly to the object through the beam scanner 115.

An example of cross sections of the first and second laser beams in the beam splitter is shown in FIG. 4B, and the distance between the two laser beams can be freely controlled by changing the position of the second mirror 10515.

In addition, the optical axis of the laser beam emitted from the polarizing beam splitter 10513 should be controlled to be parallel to the optical axis of the laser beam incident to the beam splitter 10511, and the optical axis of the laser beam reflected from the beam scanner 115 is an object. Of course, it should be controlled to be perpendicular to the.

In addition, the polarizer 10512 may use a polarizer that converts horizontal linearly polarized light (P polarization) into vertical linearly polarized light (S polarization), and the polarizing beam splitter 10513 is a polarizing beam splitter that transmits P polarized light and reflects S polarized light. Can be used.

5A and 5B are a third illustration of the beam splitting means shown in FIG. 1 and a cross-sectional view of a split beam, wherein a laser beam is divided into two using a beam splitter, and any one of the two divided laser beams is used by a prism. The process is divided into two, and the laser beam is divided into three.

As shown in Fig. 5A, the beam splitting means 105 is a beam splitter 10521 for dividing an incident laser beam, and a polarizer 10522 for converting polarization characteristics of the laser beam reflected from the beam splitter 10521. A prism 10523 for dividing the laser beam polarized by the polarizer 10522 into first and second laser beams, and a first mirror 10525 for reflecting the third laser beam transmitted through the beam splitter 10521. ), A second mirror 10526 for reflecting the third laser beam reflected from the first mirror 10525, a first and a second laser beam exiting the prism 10523, and a second mirror 10526. And a polarizing beam splitter 10424 for transmitting a third laser beam incident through the beam, wherein the first to third laser beams reflected or transmitted by the polarizing beam splitter 10524 are transmitted through the beam scanner 115. Irradiated perpendicular to the object.

An example of a cross section of the laser beam divided by the beam splitting means according to the present embodiment is shown in FIG. 5B, and the distance between the first and second laser beams is adjusted by controlling the refraction of the prism 10523, while the prism The arrangement of the 105105 may be controlled so that the two laser beams may be symmetrical, and the position of the second mirror 10526 may be controlled to adjust the position of the third laser beam.

Here, the polarizer 10522 may use a polarizer that converts horizontal linearly polarized light (P polarized light) into vertical linearly polarized light (S polarized light), and the polarizing beam splitter 10524 is a polarizing beam splitter that transmits P polarized light and reflects S polarized light. Can be used.

6A and 6B are a fourth exemplary view of the beam splitting means shown in FIG. 1 and a cross-sectional view of the splitting beam, in which one laser beam is divided into two using a prism, and then the two divided laser beams are respectively divided by a beam splitter. The case of dividing into two beams in total is shown.

As shown in Fig. 6A, the beam splitting means 105 is a prism 10531 for dividing the incident laser beam, and a beam splitter for dividing and reflecting the two divided beams in the prism 10531, respectively. 10532, a polarizer 10533 for converting polarization characteristics of the first and second laser beams reflected by the beam splitter 10532, and for reflecting the third and fourth laser beams transmitted by the beam splitter 10532 Reflects the first and second laser beams whose polarization characteristics have been changed in the first mirror 10535, the second mirror 10536 for reflecting the laser beam reflected from the first mirror 10535, and the polarizer 10533, And a polarization beam splitter 10534 for transmitting the third and fourth laser beams incident through the second mirror 10536, wherein the first to fourth laser beams reflected or transmitted by the polarization beam splitter 10534 are beams. It is irradiated perpendicular to the object through the scanner 115.

An example of a cross section of the laser beam divided by the laser beam splitting means according to the present embodiment is shown in FIG. 5B, and the interval between the first to fourth laser beams is the refractive index of the prism 10531 or the second mirror 10536. It can be changed by controlling the arrangement of. However, at this time, the optical axis of the laser beam reflected from the second mirror 10536 should be parallel to the optical axis of the laser beam incident to the prism 10531, and the optical axis of the laser beam reflected from the beam scanner 115 is perpendicular to the object. Of course, to control to achieve.

In the present invention described above, the laser beam is divided into two or more laser beams by a prism, a beam splitter, or a combination of the prism and the beam splitter, and the object is processed using the same. Since the sum of the energy of the divided laser beams is equal to the energy of the laser beam before the division, the processing speed can be maintained, and the narrow line width can be ensured because the intensity of each of the divided laser beams is lower than the intensity of the laser beam before the division. The distance between the divided laser beams can be easily changed according to the arrangement of the optical systems constituting the beam splitting means.

In addition, the divided laser beam may be irradiated while moving the laser beam by irradiating the object 119 with the beam scanner 115 to obtain the effect of irradiating the laser beam with the stage 121 while processing the object. By feeding at least once in the direction opposite to the direction, the machining speed can be further improved.

In the laser processing apparatus shown in FIG. 1, the beam scanner 115 can also be comprised using a polygon mirror. The polygon mirror has a plurality of reflective surfaces and is a rotating polygon mirror rotating around a rotation axis, which will be described with reference to FIG. 7 as follows.

7 is a view for explaining a concept of object processing using a polygon mirror applied to the present invention.

The polygon mirror 115-1 having n reflective surfaces rotates at a constant speed ω and a rotation period T about the rotation axis 11. At this time, the incident laser beam is reflected on the reflective surface and irradiated to the object 119 through the optical system 117.

In the polygon mirror 115-1 having n reflecting surfaces 12, the scanning angle θ of the laser beam when one surface of the reflecting surface 12 rotates is represented by the following equation (1).

∴

)의 크기의 2배임을 알 수 있다. 따라서 폴리곤 미러(115-1)의 반사면(12)에서 반사된 레이저 빔이 대상물(119)에 조사되는 길이인 스캐닝 길이(scanning length)는 레이저 빔을 대상물(119)로 조사하는 광학계(117)의 특성에 의해 결정되며 다음의 수학식 2와 같다.According to Equation 1, the scanning angle θ is a center angle occupied by one reflective surface 12 of the polygon mirror 115-1.

It can be seen that twice the size of). Therefore, the scanning length, which is a length at which the laser beam reflected from the reflecting surface 12 of the polygon mirror 115-1 is irradiated to the object 119, is an optical system 117 that irradiates the laser beam to the object 119. It is determined by the characteristic of and is given by Equation 2 below.

S _L : scanning length

f: focal length

θ: scanning angle

According to Equation 2, when the polygon mirror 115-1 is rotated, the laser beam reflected from each reflecting surface 12 of the polygon mirror 115-1 is irradiated onto the object 119 by an S _L length. That is, the scanning length of the laser beam irradiated onto the object 119 according to the rotation of the polygon mirror 115-1 is the focal length of the optical system 117 and the reflecting surface 12 of the polygon mirror 115-1. Calculated by the product of the angles of the laser beam reflected by

Meanwhile, since the polygon mirror 115-1 has n reflective surfaces 12, the scanning mirror S _L is scanned n times in one rotation. That is, the laser beam irradiated onto the object 119 is irradiated onto the object 119 by the scanning length, and when the polygon mirror 115-1 rotates once, the reflective surface 12 of the polygon mirror 115-1 is rotated. The number of superimposed on the object is investigated. Accordingly, the scanning frequency during the unit time (for example, 1 second) may be expressed as in Equation 3 below.

Scanning frequency =

Scanning frequency =

ω: Angular velocity of polygon mirror

T: rotation cycle of polygon mirror

According to Equation 3, when there are n reflective surfaces 12 of the polygon mirror 115-1, the number of scanning can be adjusted by adjusting the rotation period or the angular velocity of the polygon mirror 115-1. That is, by adjusting the rotation period or the angular velocity of the polygon mirror 115-1, the scanning length can be overlapped as many times as desired.

At this time, if the angular velocity of the polygon mirror 115-1 is constant, the direction in which the laser beam is irradiated to the object 119 according to the rotation of the polygon mirror 115-1 to the stage 121 on which the object 119 is seated By transferring in the reverse direction, the relative speed at which the laser reflected by the polygon mirror 115-1 scans the object 119 increases. That is, compared to the speed at which the laser beam scans the object 119 when the stage 121 is in a stopped state, the speed at which the laser scans the object when the stage 121 is moved in the opposite direction to the irradiation direction of the laser beam. Has the effect of being faster.

FIG. 8 is a diagram for describing a concept of overlapping beams when processing an object by using a polygon mirror.

As the stage 121 on which the object 119 is mounted is transferred, the scanning length S _L by the laser beam overlaps and moves in the direction opposite to the transfer direction of the stage 121. That is, as the stage 121 is transferred, the laser beam is processed (cut) while scanning the object 119 in a direction opposite to the transfer direction of the stage 121. At this time, the scanning length S _L is uniformly overlapped within a predetermined section, and the number of overlaps can be controlled by adjusting the feed speed of the stage 121.

When the distance that the scanning length S _L moves along with the transfer of the stage 121 is _L , the overlapping degree N of the scanning distances may be expressed as S _L / L.

ℓ is the distance traveled by the stage 121 moving at the speed v during the time required for the one reflective surface 12 of the polygon mirror 115-1 to rotate, as shown in Equation 4. (N) can be expressed as in Equation 5.

중첩도(N) =

Nesting Degree (N) =

In summary, the angular velocity of the polygon mirror 115-1 for processing (cutting) the object 119 at a speed v and having a scanning overlapping degree N is expressed by Equation 6 below.

As shown in Equation 6, the angular velocity of the polygon mirror 115-1 is the product of the overlapping number N of the laser beams and the cutting speed v of the object 1190, and the focal length f of the optical system 117. It is calculated by dividing by a value of 2 times, and the cutting speed v of the object 119 is the conveying speed of the stage 121 on which the object 119 is seated.

In the above-described embodiment, the polygon mirror is illustrated as having eight reflective surfaces with eight angles, but it is obvious that the polygon mirror can be changed within the scope of the present invention.

9 is a schematic configuration diagram of a laser processing apparatus according to a first embodiment of the present invention when a polygon mirror is applied.

The driver 107 drives the polygon mirror 115-1 by using a motor (not shown), and the laser beam split at least in two by the beam splitting means 105 to the reflecting surface of the polygon mirror 115-1. The incident light is reflected by the optical system 117. At this time, since the polygon mirror 115-1 rotates at a constant speed, it is possible to obtain the effect of irradiating while moving the laser beam, and the stage is moved by the stage transfer means 123 in the opposite direction to the irradiation direction of the laser beam irradiated in this way. By transferring the 121, the processing speed of the object can be increased.

In the laser processing apparatus using the polygon mirror described above, the laser beam must be accurately incident to the longitudinal center of the polygon mirror reflection surface to process the object without error. By the way, even if the laser beam is correctly incident to the polygon mirror, if the reflective surface of the polygon mirror is not uniform, the reflection angle is distorted. In other words, the laser beam reflected from the polygon mirror by the dynamic track of the polygon mirror is not accurately irradiated to the object. This causes errors in machining the object, lowers production yield and reliability. Therefore, the error of the polygon mirror is measured in advance before the object is processed to analyze the error, and the direction of the laser beam incident on the polygon mirror when the object is actually processed. It is important to compensate the error of the laser processing apparatus by adjusting the value according to the previously analyzed error value.

10 is a configuration diagram of a laser processing apparatus to which a polygon mirror having an error correction function is applied.

In the laser processing apparatus according to the present embodiment, in addition to the laser processing apparatus shown in FIG. 1, the error correction means 125 and the polygon mirror 115-1 analyzing the error of the polygon mirror under the control of the controller 101. The mirror 202 for correcting the irradiation direction of the laser beam emitted from the beam splitter 105 under the control of the controller 101 according to the encoder 127 and the error correcting means 125 analyzed by the encoder. It further comprises an actuator 200 is mounted.

In the laser processing apparatus having such a configuration, the laser processing apparatus is tested in order to measure the error of the polygon mirror 115-1 in advance. That is, the polygon mirror 115-1 is rotated by the driver 107 under the control of the control unit 101, and the low energy (energy lower than the energy at the time of processing the actual object) emitted from the laser generating means 103 is obtained. The laser beam is split through the beam splitting means 105 and scanned into the polygon mirror 115-1.

Accordingly, the laser beam incident on the polygon mirror 115-1 is reflected in the direction of the optical system 117 on the reflection surface 12 of the polygon mirror 115-1 rotating by the driver 107. Subsequently, the optical system 117 focuses the laser beam reflected from the reflecting surface 12 and is irradiated perpendicularly to the test object.

If an error exists in the reflecting surface of the polygon mirror 115-1, the test object will not be irradiated with the laser beam in a straight line, and the operator can use the result of processing the test object to The error is measured, and the result is input to the error correction means 125 through the input unit 109. At this time, in order to accurately measure the error of the polygon mirror, it is preferable to perform the test run a plurality of times to measure the error. On the other hand, when controlling the irradiation of the laser beam energy very low, the error can be measured using the waveform of the laser beam irradiated to the test object, not the processing result of the test object.

The error correction means 125 calculates an error compensation value, that is, an incident angle adjustment value of the laser beam, on each reflection surface of the polygon mirror with reference to the measured error value of the polygon mirror, and stores it in the storage unit 113.

In this way, after analyzing the error of the polygon mirror through the test operation, it is possible to perform the actual object processing. The encoder 127 attached to the polygon mirror 115-1 converts the position and velocity information of the polygon mirror 115-1 into an electrical signal and outputs it to the controller 101 when the actual object is processed. The actuator 200 is driven by extracting an error compensation value corresponding to the reflection surface of the polygon mirror input from the encoder 127. That is, in order to prevent the laser beam from being irradiated on the reflective surface of the polygon mirror to be irradiated so that the reflection angle of the laser beam is incorrectly irradiated to the object to be processed, the direction of the mirror 202 is changed by the actuator 200. By adjusting the angle of incidence of the laser beam to the polygon mirror reflecting surface, the angle of the laser beam reflected from the reflecting surface is always controlled.

Here, the encoder 127 may be implemented as a rotary encoder which is a sensor for detecting rotational motion. The rotary encoder includes an optical rotary encoder, which is a sensor that detects rotational displacement by attaching a scale plate to a rotating shaft that rotates using a light source and a photoelectric element, or a magnetic rotary encoder, which is a sensor that detects rotational displacement by mounting a magnetic rotation sensor. have.

On the other hand, when the polygon mirror is applied by the laser processing apparatus according to the first embodiment of the present invention, if the laser beam irradiated to the object has a large energy (about 10 W), the laser beam is overheated at the same processing position of the object. As a result, the object may be damaged, thereby lowering reliability in processing the object. In addition, in the laser processing apparatus, it is common to use a laser beam having a designated aperture, not a point beam. In this case, when the laser beam is incident on the edge of the polygon mirror reflection surface, part of the laser beam may be lost. have. This will be described with reference to FIG. 11 as follows.

FIG. 11 is a diagram for describing a phenomenon in which energy loss occurs at a corner of a reflection surface of a polygon mirror.

As shown, a laser beam having an aperture designated by the polygon mirror 115-1 is incident, and a laser beam having an aperture designated by the rotation of the polygon mirror 115-1 is applied to the corner portion of the reflective surface 12. When incident, part of the laser beam (energy attenuation laser beam; A) is reflected at the reflecting surface 12 and is incident on the optical system 117, while the remaining laser beam (loss laser beam; B) is the reflecting surface 12 '. Since the light is incident on the optical system 117, it is not incident on the optical system 117.

Accordingly, since the optical system 117 focuses only the energy attenuation laser beam A and irradiates the object 119 on the stage 121, the processing efficiency at this machining position and the machining at another machining position of the object 119 are performed. The rate is different, and thus, the object 119 cannot be processed uniformly, resulting in a decrease in reliability of the process. In addition, the energy of the laser beam is lost at the corners of the polygon mirror reflecting surface, resulting in waste of resources.

Therefore, in the present embodiment, a polygon mirror is used in which the number of reflecting surfaces is controlled so that the aperture of the incident laser beam covers two or more reflecting surfaces of the polygon mirror.

12A and 12B are diagrams for explaining an energy loss relationship in a polygon mirror according to incidence of a laser beam.

Referring to FIG. 12A, when a laser beam having an aperture D designated as a corner portion of one reflective surface of the polygon mirror 115-1 is incident and reflected, a part of the laser beam (energy attenuation laser beam; A) is While incident on the reflecting surface 12, the remainder (loss laser beam) B is incident on the reflecting surface 12 ′. Therefore, the laser beam incident on the reflecting surface 12 is reflected from the reflecting surface 12 in a state where energy is attenuated by the laser beam incident on the reflecting surface 12 '.

On the other hand, in order to calculate the ratio of the scanning length processed by the energy loss laser beam A with respect to the entire scanning length processed by one reflective surface of the polygon mirror 115-1, the polygon mirror 115-1 The circumscribed circle 13 is drawn at the center, and the point where the energy loss laser beam A meets the circumscribed circle 13 of the polygon mirror 10 is connected to the center of the polygon mirror 10 (ie, the axis of rotation 11). The angle obtained in this manner will be referred to as loss angle t _θ . Next, a ratio (hereinafter, referred to as a 'loss ratio') of a portion lost to one reflective surface of the polygon mirror 115-1 having N reflective surfaces will be described.

In FIG. 12A, the length of a fan-shaped arc obtained by connecting the point where the circumferential circle 13 of the polygon mirror 115-1 and the one reflective surface meet with the rotation axis, that is, the one reflective surface of the polygon mirror to which the laser beam is irradiated The length of the arc for the C1 is as shown in Equation 7.

Further, the length C2 of the arc for the loss angle portion is equal to Equation 8, and Equation 8 particularly represents the maximum arc length for the loss angle portion.

The arc length (C2) for each loss part is a value that changes as the polygon mirror rotates. When the laser beam is irradiated without including the edge portion of the polygon mirror, the loss ratio becomes zero since the loss laser beam does not exist. When the polygon mirror is rotated and the laser beam starts to be irradiated including the edge portion of the polygon mirror, the loss rate gradually increases and then decreases again after the maximum value as shown in Equation (8).

In addition, the percentage of the portion where the energy is attenuated and reflected on one reflective surface of the polygon mirror (t _r , Hereinafter, 'loss ratio' may be expressed as in Equation 9.

In addition, the loss angle t _θ can be expressed by Equation 10, and the vertical distance h from the center of the polygon mirror shown in FIG. 12B to the center of the laser beam irradiated to the reflecting surface is expressed by Equation 11 Can be represented.

Here, R represents the length of the radius of the polygon mirror circumscribed circle. Meanwhile, as shown in FIG. 12B, the scanning angle θ at one reflection surface of the polygon mirror with respect to the incident laser beam is expressed by Equation 12. FIG.

Table 1 shows the relationship between the loss factor at one reflective surface of the polygon mirror and the number of beams split. A loss rate of less than 100% means that C2 is smaller than C1 in the above equation, that is, a laser beam is input by covering one reflecting surface, and a loss rate of 100% or more means that C2 is higher than C1 in the above equation. In other words, it means that the incident laser beam is input by covering two or more reflection surfaces.

Loss rate (t _r ,%) Beam split number 0-99 1 ~ 2 100-199 2 ~ 3 200-299 3 ~ 4 : :

If the loss ratio is 0 to 99, the laser beam is divided into one or two after being incident on the reflecting surface of the polygon mirror, and if the loss ratio is 100 to 199, the laser beam is divided into two or three, and the loss ratio is 200 to 299 In this case, the laser beam is divided into three or four. In other words, as the loss rate increases, the number of split beams increases. Further, when the laser beam is divided into two or three, the aperture D of the laser beam is incident to a size that can cover the two edges of the polygon mirror reflection surface, and the laser beam is divided into three or four. The case is where the aperture D of the laser beam is incident with a size that can cover the three edges of the polygon mirror reflecting surface.

In the above, the splitting of the laser beam into one or two is a phenomenon in which the laser beam irradiated to the edge portion of the reflective surface is reflected as the polygon mirror and the polygon mirror rotate due to the characteristics of the polygon mirror and the laser beam, and thus it is difficult to regard it as an effective beam splitting. The case where the laser beam is divided into two or three, three or four and more can be regarded as an effective beam splitting phenomenon.

As can be seen from Equation 9 to Equation 11, the loss ratio, that is, the number of split beams, increases as the number N of reflecting surfaces increases, and as the diameter D of the input laser beam increases, the polygon mirror It increases as the length R of the circumscribed circle decreases. Further, as can be seen in Equation 12, as the number N of reflecting surfaces increases, the scanning angle at one reflecting surface of the polygon mirror is gradually reduced, and as a result, the laser beam is split and reflected at one reflecting surface of the polygon mirror. All can be condensed by the optical system 117.

As such, when the laser beam is divided and irradiated to the object, the effect of irradiating the same processing surface with multiple times at the same time with low energy can be obtained, thereby improving the processing quality of the object as well as improving the yield.

FIG. 13 is a view for explaining a concept of processing an object using a polygon mirror when a laser beam is incident to cover a plurality of reflective surfaces of the polygon mirror. The polygon mirror is enlarged and partially illustrated for convenience of description.

As shown in the drawing, a laser beam having a designated aperture D is irradiated to a polygon mirror having a plurality of reflective surfaces. In this case, the polygon mirror is implemented so that the laser beam can be irradiated by covering the three reflective surfaces of the polygon mirror, for example. That is, by controlling the number of reflection surfaces of the polygon mirror so that the loss ratio is 100 to 199%.

When the laser beam is incident on the designated aperture D, the laser beam is irradiated to all of the reflecting surfaces N1 and N2 and a part of N3 of the polygon mirror 115-1. The laser beam irradiated onto the reflecting surface N1 is irradiated to the object 119 focused on the stage 121 and focused on the optical system 117, and the scanning angle on the reflecting surface N1 is rotated as the polygon mirror is rotated. The object 119 is processed within the range. The laser beam irradiated to the reflecting surface N2 and the laser beam incident on a part of the reflecting surface N3 are also irradiated onto the object 119 by the same principle.

As described above, when processing an object using a laser beam having a specified aperture rather than a point beam, the laser beam is controlled by controlling the number of reflection surfaces of the polygon mirror so that the laser beam is incident on the plurality of reflection surfaces of the polygon mirror. It can be divided into pieces, and each of the divided laser beams can irradiate the processed surface of the object multiple times at the same time.

In particular, in the present invention, since the laser beam is divided into a plurality of pieces by the beam dividing means 105 before the laser beam is incident on the polygon mirror 115-1, the laser beam is applied to the processed portion of the object with low energy. A plurality of irradiation results can be obtained, and since a plurality of laser beams are incident at the same time, processing can be performed at a narrow line width while maintaining the processing speed at the level before beam splitting, and the quality after processing can also be guaranteed.

14 is a configuration diagram of the laser processing apparatus according to the first embodiment of the present invention when AOD is applied.

The Acousto-Optic Deflector (AOD) is an optical drive capable of scanning microscopic areas at high speed.

In a laser scanning system, the laser beam must be precisely adjusted to a desired position. Currently, a galvano scanning mirror or a polygon mirror is mainly used. However, these optical driving devices are difficult to increase the position accuracy to a resolution of several μm or less, and have a scanning frequency of ㎑, resulting in speed constraints when interlocked with a laser beam PRF (PRF) of more than 50 kHz recently. .

In order to overcome this limitation of precision and speed in the optical drive device, a laser processing apparatus may be implemented using AOD using acoustic-optic technology, which is illustrated in FIG. 14.

The laser processing apparatus shown in FIG. 14 includes a high frequency (RF) driver 300 and an AOD 302 unlike those shown in FIG.

Currently, an acoustic-optic modulator, which is mainly used for Q-switching oscillation of lasers, is driven by a high frequency driver of MHz. Here, Q-switching is one of the techniques for making a laser light pulse output beam. When the Q value (resonance value) of the laser resonator is dropped, the energy is accumulated in the laser medium, and the Q value is suddenly raised. Then, the oscillation starts, and the accumulated energy is released as a quick and sharp light pulse. Using Q-switching in the laser yields several GW of power.

In such an acoustic-optic modulator, when the phase difference is adjusted with two high frequency input signals, a laser beam that rotates the small and wheat boundary waves of sound waves at a small angle is output.

Therefore, in the laser processing apparatus according to the present embodiment, two high frequency signals (for example, a signal of 80 MHz) are input to the AOD 302 through the RF driver 300. Then, the sound wave proceeds through the AOD 302, and the laser beam input from the beam splitter 105 rotates between scanning angles determined according to the frequency of the high frequency signal input through the RF driver 300. Will be output.

When AOD is used, the object can be processed at a speed of 10 times or more and 100 times or more than a polygon mirror. In addition, since the MHz scanning is possible, the frequency is 100 times faster than that of the PRF, and thus the laser beam can be uniformly irradiated at each position regardless of the deceleration / deceleration section over the processing section.

Laser processing device with laser beam splitting and beam shaping function

When the laser beam is irradiated onto the object, the irradiated portion of the laser beam is removed, and the by-products generated are discharged in the vertical direction of the cutting plane. When the depth of the object is not deep, the by-products are easily discharged to the outside, but as the depth of the recess increases, the by-products sublimated or vaporized by the laser beam irradiation are not discharged to the outside and condensation is formed on the wall of the object. And recast.

As such, the problem that the by-products are re-deposited and the cutting efficiency of the object is lowered can be inferred to be solved by widening the cutting width of the object. In other words, by increasing the cutting width of the object will increase the external emissions of the by-products will be able to minimize the amount of by-products redeposited on the cutting surface of the object. However, if the cutting width of the object is increased, the focus of the laser beam must be enlarged, so the beam intensity of the beam is lowered and the cutting width is widened, but the removal efficiency of the by-products is reduced and the object is not completely cut. . That is, the focusing intensity of the beam is represented by the intensity of the laser beam per irradiation area. As the focal area of the beam is enlarged, the irradiation area increases by that amount, so that the focusing intensity of the beam is lowered. In addition, in the case of an object requiring fine processing, there is a limit in increasing the cutting width, and by this method, by-products generated during laser processing cannot be effectively removed.

On the other hand, when cutting an object, it is possible to irradiate a laser beam on the object while moving the stage on which the object is mounted through the stage transporting device. This actually irradiates the laser beam vertically, but as a result, the laser beam is irradiated at an oblique position. The same phenomenon will appear. This phenomenon appears larger as the object feeding speed is faster.

15 is a view for explaining that by-products are discharged when the object is processed using a laser while transporting the object.

As shown, when the laser beam is irradiated while moving the object, the result is that the laser beam is obliquely irradiated onto the object, and accordingly, the cutting plane of the object is inclined in the irradiation direction of the laser beam (the direction opposite to the object conveyance direction). It turns out that it has a diagonal shape. By-product (E) generated when cutting the object is discharged in the vertical direction of the cutting surface in this case it can be seen that the discharge of the by-product (E) is easy.

As such, when the cut surface of the object has an inclination toward the outside, the by-products are easily discharged, and the effect will be greater as the inclination is lower. However, if the conveying speed of the object is increased, the focusing intensity of the beam is lowered so that the object is not cut and melted, and the process atmosphere becomes unstable, such as the object being shaken as the stage conveying apparatus moves at a high speed.

Therefore, this invention provides the laser processing apparatus which can shape the shape of the laser beam irradiated to an object to ellipse.

16 is a configuration diagram of a laser processing apparatus according to a second embodiment of the present invention.

The laser processing apparatus according to the present embodiment includes at least two laser beams emitted from the control unit 101 for controlling the overall operation, the laser generating means 103 for outputting a laser beam having a specified aperture, and the laser generating means 103. A beam dividing means 105 for dividing into pieces, a driver 107 for driving the mirror 129, an input portion 109 for inputting control parameters and a control command, an output portion 111 for displaying information such as an operation state, and the like. In addition, the storage unit 113 for storing data, the mirror 129 for reflecting the laser beam emitted from the beam splitter 105 to the processing site on the object, and the laser beam reflected from the mirror 129 to focus on the object At least two beam forming parts 131-1, 131-2; 131, and an object 119 are processed to deform the shape of the laser beam passing through the optical system 117 and the optical system 117 into ellipses, respectively. During the stage 121 And a stage transfer means 123 for transferring at least once in a direction opposite to the irradiation direction of the laser beam.

The mirror 129 may be configured as a polygon mirror, and the optical system 117 may be configured as a condenser lens. When the mirror 129 is configured as a polygon mirror, the error can be corrected by the error correction means 125, the encoder 127, the actuator 200, and the like as shown in FIG.

In addition, as illustrated in FIG. 17, the beam shaping unit 131 may include, for example, a first cylindrical lens 1310 and a second cylindrical lens 1320. The first cylindrical lens 1310 is a long focal lens and transforms the laser beam into sectional light, and the second cylindrical lens 1311 is a short focal lens by a specified distance such that the transmission direction is perpendicular to the first cylindrical lens 1310. Spaced apart from each other, the cross-sectional light transmitted from the first cylindrical lens 1310 is transformed into an elliptical beam and transmitted. In addition, by adjusting the position of the first cylindrical lens 1310 up and down, the size of the beam irradiated to the surface to be processed can be changed.

The size of the elliptical laser beam is to increase the length of the long axis as the output of the laser beam is increased, on the contrary, if the output is reduced, the length of the long axis is reduced. That is, the focal plane size should be changed according to the output of the laser beam to maintain the focusing intensity of the beam.

In FIG. 17, the beam shaping unit 131 has been described using a cylindrical lens. However, the beam shaping unit 131 may be configured by using any one of all possible elements that may transform the shape of the laser beam into an ellipse.

18 is a view for explaining sublimation of by-products during object processing using the laser processing apparatus according to the second embodiment of the present invention.

The object 119 is moved by the stage transfer device 123, and cutting starts in a direction opposite to the transfer direction. The laser beam irradiated through the beam shaping unit 131 causes the cutting plane of the object to be cut diagonally. That is, the cutting surface of the object has an oblique shape inclined in the cutting direction of the object. At this time, the length of the cut surface is the length D1 of the long axis of the laser beam, and the cut width is the length D2 of the short axis of the laser beam.

Since the laser beam is elliptical and the cutting surface of the object is cut in an oblique shape, all by-products E generated from the cutting surface are discharged to the outside and are not isolated at the lower end of the cutting portion.

As described above, the size of the elliptical laser beam irradiated to the object 119 is preferably a ratio of the length of the short axis and the long axis is 1: 4 to 1:12, but the ratio is depending on the total depth of the object 119 to be cut. May be variable.

Since the method of processing the object 119 using the laser processing apparatus is similar to that described with reference to FIG. 1, a detailed description thereof will be omitted.

Laser processing unit with laser beam splitting and filtering

The laser processing apparatus shown in FIG. 1 processes the object by dividing the laser beam into two or more and by processing the object by irradiating the laser beam through the beam scanner and simultaneously transferring the object in the direction opposite to the irradiation direction of the laser beam. And the speed can be improved.

19A to 19D are diagrams for describing a concept in which a laser beam is repeatedly irradiated to an object in a general laser processing apparatus, and it will be described on the assumption that the object is fixed for convenience of description.

As shown in FIG. 19, it can be seen that as the mirror (320 of FIG. 2) of the beam scanner is gradually inclined, the position where the laser beam is irradiated to the object 119 is changed as it moves from FIG. 19A to FIG. 19D. Since the laser beam is continuously scanned and the mirror 320 is also continuously moving, the laser beam is irradiated in a straight line to the processing surface of the object 119, and the surface of the object 119 is continuously processed in a straight line (1, 2, 3).

After the mirror 320 is rotated and moved to the set angle in this manner, the mirror 320 is reversely rotated from FIG. 19D to FIG. 19A.

However, when the mirror 320 of the beam scanner repeats the rotation at the designated angle, the laser beam does not move at the rotation return point and is repeatedly irradiated. As a result, the processing area of the object to which the laser beam returns the rotational return point of the mirror is recessed more deeply than other processing areas, thereby decreasing processing uniformity.

Therefore, the present embodiment proposes a laser processing apparatus incorporating a mask in order to solve the processing nonuniformity of the object at the return point of rotation of the mirror.

20 is a schematic configuration diagram of a laser machining apparatus according to a third embodiment of the present invention.

In addition to the configuration shown in FIG. 1, the laser processing apparatus according to the present embodiment includes a hole for filtering the laser beam emitted at the rotational return point of the mirror (320 of FIG. 2) when the laser beam is emitted from the beam scanner 115. It further includes a mask 400 including (H).

Here, the mask 400 may be installed between the beam scanner 115 and the optical system 117 or between the optical system 117 and the object 119, the material or the laser beam that can reflect the laser beam, such as metal It is manufactured using materials that can absorb the

In such a laser processing apparatus, the laser beam irradiated at the rotational return point of the mirror of the beam scanner 115 is irradiated and reflected to the area around the hole H of the mask 400, and thus passes through the hole H and the object ( The laser beam irradiated to 119 is uniformly irradiated without the point where the moving speed becomes zero. That is, in this embodiment, the mask 400 serves to reflect the laser beam irradiated at the point where the moving speed of the mirror 320 of the beam scanner 155 becomes zero.

21 is a view for explaining the concept that the object surface is uniformly processed by the laser processing apparatus according to the third embodiment of the present invention.

As shown, when the mirror 320 repeats the rotation, the speed becomes zero at the first end and the second end to change the direction of the mirror, and at this point, the laser beam is irradiated on the processing surface of the object. In order to prevent that, the mask 400 having the hole H is introduced to filter the laser beams emitted from the first and second ends.

A plurality of masks 400 may be manufactured according to the size of the holes H, and may be replaced according to the scanning width of the laser beam. When the size of the holes H of the mask 400 is constant, the mask 400 may be emitted from the return point of rotation of the mirror. In order to filter the laser beam, the scanning width of the beam passing through the hole H may be adjusted by lowering or raising the mask 400. In addition, when the mask 400 may not be replaced or moved, the scanning width of the laser beam may be adjusted by adjusting the rotation angle of the mirror 320 of the beam scanner 115.

In addition, the mask 400 is preferably implemented by the number of beams divided by the beam splitter 105.

Laser processing unit with laser beam splitting and object cooling

In laser processing, particles generated at the focused portion of the beam come into contact with the surface of the object to affect the performance of the object. In order to remove such particles, the object must be cleaned, and in this case, another error occurs because the object is exposed to the cleaning material.

In order to solve this problem, a method of forming a coating layer on the surface of an object before processing the object with a laser beam is used. By the way, after processing the object to form a coating layer, the cleaning process for removing the coating layer should be accompanied separately, and the cleaning liquid for cleaning the coating layer will include particles generated during the object processing, a separate filter device for recovering such particles Will be needed.

Therefore, in the present embodiment, the object surface is frozen using water vapor in the processing chamber when the object is processed, and this ice layer is used as a coating layer, thereby simplifying the object processing process, and removing the freezing layer after the object processing is completed. The removed particles are recovered using a filter to minimize the generation of industrial wastewater.

22 is a schematic configuration diagram of a laser machining apparatus according to a fourth embodiment of the present invention.

In addition to the configuration of the laser processing apparatus shown in FIG. 1 (or FIG. 16), the laser processing apparatus shown in FIG. 22 includes a thermoelectric cooling module (TEC Module) 502, a heat insulating means 504, and a humidification means ( 506, sensor 508 and thawing means 510, which are each controlled by the controller 101. In addition, the object 119 is loaded into the chamber 500.

In such a laser processing apparatus, as the thermoelectric element 502 starts cooling, the stage 121 on the thermoelectric element 502 is cooled, and as a result, the temperature of the object 119 is lowered. Since the temperature in the chamber 500 is room temperature, as the temperature of the object 119 is lowered, water vapor condenses due to the temperature difference, and condensation occurs on the surface of the object 119, and the thermoelectric element 502 continues to cool. As it continues, the ice layer 135 is formed on the surface of the object 119.

The freezing layer 135 serves as a coating layer to protect the surface of the object 119 when the object 119 is processed using a laser beam and to prevent incidental particles from directly contacting the surface of the object 119. Do it.

That is, by cooling the object 119 on the stage 121 with the thermoelectric element 502, the ice layer 135 as a coating layer is formed on the object 119 and the laser beam divided by the beam splitting means 105. Is irradiated onto the object 10 through the beam scanner 115 (or the mirror 129) and the optical system 117. At this time, since the freezing layer 135 is formed on the object 119, particles generated while the object 119 is processed by the laser beam are attached to the freezing layer 135. When the processing is completed, the object 119 is cleaned by melting the ice layer 135, and the particles attached to the ice layer 135 are also removed. Therefore, the water generated by melting the freezing layer contains particles, and by filtering the water, it is possible to recover particles that cause environmental pollution.

Meanwhile, in order to shorten the time required by cooling the object 119 after loading the object 119 into the chamber 500, the object 119 may be pre-cooled and then loaded into the chamber 500. In this case, after loading the object 119 into the chamber 500, a phenomenon may occur in which water condensation freezes between the object 119 and the stage 121, so that the preliminary cooling temperature is set higher than the dew point. desirable. The condensation point is the temperature at which water vapor begins to change into water, which is determined by the surrounding humidity. The humidity and the condensation point are proportional to each other.

As such, in the present embodiment, an ice layer 135 is formed on the surface of the object 119 by using a temperature difference between the temperature in the chamber 500 and the object 119 and used as a coating layer. Freezing is a phenomenon caused by condensation of water vapor around the ice crystals, which is a kind of growth of ice crystals, and thus the freezing layer 135 is not transparent. In this case, a pattern, ID, etc. formed on the object 119 under the freezing layer 135 The information will be unreadable. This phenomenon can be solved by a process of re-cooling after melting some of the ice layer 135, for this purpose, the laser processing apparatus of the present invention further comprises a thawing means (510).

The thawing means 510 for melting the freezing layer 135 may be configured as either a contact or non-contact type, and in the case of melting the freezing layer 135 by contact, in order to slide the surface of the freezing layer by a heated metal plate. When the thawing means 135 is composed of a metal plate, and the frosting layer 135 is melted in a non-contact manner, the thawing means 135 may be configured as a heating coil in order to spray hot air evenly onto the frosting layer 135. The contact thawing means 510 is useful when the surface of the freezing layer 135 is flat, and the non-contact thawing means 510 is useful when the surface of the freezing layer 135 is flat as well as when there is irregularities.

In addition, the thickness of the freezing layer 135 formed on the surface of the object 119 is changed according to the humidity in the chamber 500, and the humidity is also changed according to the temperature. In the present invention, the sensor 508 is attached to the chamber 500 to control the temperature and humidity in the chamber 500 to control the thickness of the freezing layer 135. Since the humidity in the chamber 500 is generally managed low, the problem of excessively high thickness of the ice layer 135 due to excessive humidity does not need to be considered, and the humidity in the chamber 500 sensed by the sensor 508 is not considered. When the temperature is less than the specified value, the humidifier means 506 is further configured to replenish moisture into the chamber 500 to prevent the humidity in the chamber 500 from insufficiently forming the freezing layer 135.

23A to 23D are diagrams for explaining an example of processing an object using the laser processing apparatus shown in FIG. 22.

As shown in Fig. 23A, the object 119 fixed on the stage is cooled by the thermoelectric element 502 at the bottom of the stage to form a freezing layer 135, and at the designated processing position as shown in Fig. 23B. Irradiate the laser beam.

After the machining is completed by irradiating the laser beam, particles G as processing by-products are attached to the surface of the freezing layer 135 as shown in FIG. 23C, and the freezing layer 137 is formed on the processing site F as well. That is, since the object 119 is maintained in a cooled state even while irradiating the laser beam, the freezing layer 137 is formed at the processing site F by the temperature difference in the object 119 and the chamber.

When the processing is completed, the object is washed dry or wet to remove the icing layers 135 and 137 and the particles G, and the processed object F having the desired processing site F, which has been cleaned as shown in FIG. 23D, is processed ( 119).

Since the object processing using the laser is a non-contact method, it is impossible to adjust the processing height of the laser beam, and the laser beam may be affected even at a point where the laser beam does not directly touch due to the thermal effect. Therefore, the stage on which the object is mounted should use a material having a very low absorption rate than the transmission / reflection rate for the laser beam during laser processing.

A processing tape is applied on the stage for object processing with a laser and the object is seated thereon. In this case, the processing tape has a thickness of 100 μm to 400 μm and has a heat resistance characteristic that can withstand up to 400 ° C.

In general, most laser beams are transmitted in the process of laser processing and hardly affect the processing tape or the chip. However, when the size of the chip is less than a certain size, for example, the width * length is within 3 mm * 3 mm or When the chip cutting line width is within 5 mm, surplus energy more than energy that can be transmitted in a narrow area is accumulated, and the energy of reflecting or scattering is increased to affect the processing tape, resulting in damage to the processing tape.

In other words, even if the stage is made of a material suitable for laser processing, the temperature of the processing tape may rise to 1000 ° C. or more depending on the processing parameters such as the diameter and thickness of the object, the size of the chip, the width and the number of the chip cutting lines. If the processing tape breaks or melts, it is damaged. As a result, if the object is to be moved to another device after processing, the chip on the object is scattered (flying chip) and there is a problem that the next operation cannot be performed. If the processing tape melts and sticks to the stage and does not fall off after processing, the entire chip on the object becomes unusable.

In order to solve this problem, in the present embodiment, a cooling function is given to the stage itself on which the object is seated.

24 is an exemplary view of a stage applied to the present invention.

The stage 121 shown in FIG. 24 has a plurality of vacuum holes formed therein, a body portion 1211 on which an object is seated, and a vacuum portion 1213 formed on a rear surface of the body portion 1211 and having a vacuum tube for sucking air. And a thermoelectric element part 1215 and a cooling conduit part 1217 which are installed at the defecation of the vacuum part 1213 and serve as a cooling part for discharging the heat accumulated in the body part 1211.

Here, the thermoelectric element 1215 serves to cool the heat generated from the body portion 1211, the cooling conduit portion 1217 is installed on the back of the thermoelectric element 1215, the refrigerant is circulated as the thermoelectric element portion It serves to cool 1215.

25A to 25D are detailed block diagrams of the stages shown in FIG. 24.

First, as shown in FIG. 25A, the body part 1211 includes a plurality of vacuum holes 12111, and a processing tape and an object are sequentially mounted on the upper surface thereof. A plurality of vacuum holes 12111 are formed in the body portion 1211, are connected to a vacuum pipe formed in an external pump (not shown), and use the vacuum pressure from the pump to adsorb and fix the object seated on the upper surface. . At this time, the vacuum pressure from the pump is preferably controlled to 50kpa to 80kpa.

In addition, the body portion 1211 may be made of any one material of quartz, porous glass, silver ceramic, uneven stone, and silver ceramic refers to a ceramic containing silver.

Next, FIG. 25B is a detailed configuration diagram of the vacuum unit 1213, and a vacuum hole 12131 is formed in the center of the vacuum unit 1213. In addition, when the plurality of vacuum holes 12111 are formed in the body portion 1211 on a plurality of concentric circles having different diameters, the vacuum tube path 12132 is radially formed according to the arrangement of the vacuum holes 12111 formed on the concentric circles. Can be formed. The object is adsorbed to the body portion 1211 by sucking air through the vacuum tube path 12132.

25C illustrates an example of the thermoelectric element 1215, and the thermoelectric element 1215 includes at least one thermoelectric element 12151.

The thermoelectric element 12151 is a functional element capable of directly converting thermal energy into electrical energy or directly converting electrical energy into thermal energy, and is also called a Peltier device. The thermoelectric element 1215 is a device that moves heat from the heat absorbing surface to the heat dissipating surface. The thermoelectric element 1215 is capable of cooling or heating by inversion of the heat transfer direction, and by controlling the voltage / current rather than the on / off control. Temperature control is possible. In addition, since there is no moving part, there is no vibration or noise, and since no Freon refrigerant is used, there is no pollution or pollution.

In FIG. 25C, the thermoelectric elements 12151 are preferably arranged radially along the vacuum tube path 12132 of the vacuum unit 1213 shown in FIG. 25B.

Next, FIG. 25D is a detailed configuration diagram of the cooling conduit portion 1217.

The cooling conduit part 1217 circulates the refrigerant introduced through the refrigerant inlet part 12171 through the cooling conduit 12173 to cool the thermoelectric element part 1215. The refrigerant introduced into the reservoir (not shown) is compressed by the compressor and supplied to the cooling conduit 12173 through the refrigerant inlet 12171 by the pump to circulate. Here, as the refrigerant, water, water and ethylene glycol (athylene glycol) mixture, air, other cooling gas or cooling liquid may be used.

In addition, a flow control valve (not shown) may be installed in the cooling conduit 12173 in order to adjust the flow rate of the refrigerant passing through the cooling conduit 12173 of the cooling conduit 1217. The flow rate can be controlled by changing the pumping rate or other parameters.

Although the cooling conduit 12173 is curved in FIG. 25D, a cooling conduit can be configured by providing a plurality of linearly extending linear cooling conduits and connecting the plurality of linear cooling conduits. The cooling conduit can also be configured spirally.

In another embodiment, the refrigerant inlet 12171 and the refrigerant outlet 12172 may be configured in plural, respectively.

The object 121 may be processed by controlling the cooling temperature differently according to whether the coating layer is formed on the surface of the object using the stage 121 as described above.

First, when processing an object in which the coating layer is not formed, an ice layer may be formed on the surface of the object in the same principle as described in FIG. 22, and the object may be safely processed without the separate coating layer forming process.

On the other hand, when processing the object on which the coating layer is formed, the temperature of the body portion 1211 should maintain a temperature above the dew point of the air. This is because the coating layer is formed of a water-soluble material. That is, when the temperature falls below the dew point temperature, water droplets start to form on the surface of the object, which causes the coating material to dissolve and thus cannot perform its original role.

In this case, the temperature of the body portion 1211 is generally preferably controlled between 0 ° C. and 20 ° C., and a temperature sensor (not shown) is attached to the body portion 1211 to sense the temperature of the body portion 1211. The body part 1211 maintains a specified temperature by controlling the power applied to the thermoelectric element part 1215 to be turned on / off according to the measured value of the temperature sensor.

The thermoelectric elements shown in Figs. 22 and 25C have the same configuration as that shown in Fig. 26, for example.

FIG. 26 is a diagram illustrating an example of a thermoelectric device according to an exemplary embodiment of the present invention. A lower conductive layer 620 and an upper conductive layer 622 are formed between a lower substrate 610 and an upper substrate 612, respectively. A semiconductor chip is formed between the 620 and the upper conductive layer 622, and cooling is performed by supplying power to the power supply cables 640 and 642.

Here, the lower substrate 610 and the upper substrate 612 serves to control current while efficiently transferring heat, and the lower conductive layer 620, the upper transfer layer 622, and the semiconductor chip serve as a substantial cooling engine. Works. In the case of a semiconductor chip, an entire P-type semiconductor and an N-type semiconductor are connected in series to exhibit maximum cooling efficiency.

Laser processing device for simultaneous processing of multiple processing lines

It may be necessary to perform a process such as multipass cutting, which simultaneously processes two or more lines of an object processing process using a laser. To this end, the present invention has to be processed while repeatedly moving the processing object or the laser beam generating apparatus several times, and thus inefficient in terms of time and cost, the present invention proposes a method for simultaneously processing a plurality of processing lines.

27 is a configuration diagram of the laser processing apparatus according to the fifth embodiment of the present invention.

As shown, the laser processing apparatus according to the present embodiment includes a control unit 101 for controlling the overall operation, at least two laser generating means 139-1 and 139-2 for outputting a laser beam having a specified aperture, and a laser. At least two beam splitters 141-1 and 141-2 which receive the laser beams emitted from the generators 139-1 and 139-2 and split them into at least two or more, respectively, and drive the reflective mirror 147. Driver 107, input unit 109 for inputting control parameters and control commands, output unit 111 for displaying information such as operation status, storage unit 113 for data storage, beam splitting means 141- 1 and 141-2, each of which is output from each of at least two mirrors 145-1 and 145-2 and beam splitters 141-1 and 141-2 for reflecting the laser beam reflected from each of them into the same position. Angle and position of the mirrors 145-1 and 145-2 to reflect the laser beam to the same position Reflecting mirrors 147 and reflecting mirrors reflecting laser beams reflected from the actuators 143-1 and 143-2 and the mirrors 145-1 and 145-2 to be adjusted to the same positions in different directions, respectively. Reflective mirror driving means 149 for repeatedly rotating the reflective mirror 147 within a predetermined angle range so that the 147 has a predetermined angular velocity and an optical system 117 for condensing the laser beam reflected from the reflective mirror 147. The object 119 is mounted on the stage 121.

In a preferred embodiment of the present invention, the laser processing apparatus comprises a stage transfer means for transferring the stage 121 on which the object 119 is seated at least once in a direction opposite to the irradiation direction of the laser beam during the processing of the object 119 ( 123 may be further included.

In addition, the optical system 117 is preferably implemented by a condensing lens.

Here, the mirrors 145-1 and 145-2 reflect the respective laser beams output from the beam splitters 141-1 and 141-2 toward the same position of the reflecting mirror 147 to reflect the mirrors 147. By using the actuators 143-1 and 143-2, the tilt and position of the mirrors 145-1 and 145-2 are adjusted so that the laser beams can be reflected in different directions. .

The reflective mirror 147 is installed in a vertical direction with the stage 121 on which the object 119 to be processed is mounted, and the optical system 117 is horizontally with the stage 121 on which the object 119 to be processed is mounted. It is installed to focus the laser beam reflected from the reflection mirror 147.

In addition, the mirrors 145-1 and 145-2 have their tilts and positions adjustable by the respective actuators 143-1 and 143-2, so that the lasers reflected in different directions by the reflecting mirrors 147, respectively. The beam is focused by the optical system 117 to adjust the spacing and position between the pair of laser beams irradiated perpendicularly to the object 119 seated on the stage 121.

On the other hand, the reflection mirror driving means 149 is configured to repeatedly rotate the reflection mirror 147 at a predetermined speed within a predetermined angle range, and the reflection mirror 147 at a predetermined speed under a predetermined speed under the control of the controller 101. Rotate repeatedly within.

According to the laser processing apparatus having such a configuration, the first and second beam splitters 141-1 and 141-2 are divided into at least two, respectively, under the control of the controller 101, and the first and second beams are divided. The laser beams split by the dividing means 141-1 and 141-2 are incident on the first mirror 145-1 and the second mirror 145-2, respectively. The inclination and the position of the first and second mirrors 145-1 and 145-2 are adjusted by the actuators 143-1 and 143-2, respectively, and the reflections rotate by the reflection mirror driving means 149. The laser beam is incident on the same position of the mirror 147. Thereafter, the laser beams reflected from the reflection mirror 147 are focused at different positions of the optical system 117 and irradiated to the object 119 in the vertical direction.

At this time, the inclination angles and positions of the first mirror 145-1 and the second mirror 145-2 are adjusted using the actuators 143-1 and 143-2 to irradiate the object 119 in the vertical direction. The distance between the pair of laser beams can be adjusted.

In addition, when the reflective surface of the reflective mirror 147 rotates by a predetermined range, the laser beam irradiated to the object 119 is moved by the scanning length in the direction opposite to the transfer direction of the stage 121.

Although not shown, the laser processing apparatus according to the present embodiment may be provided with at least two beam forming parts so as to modify the shape of the laser beam passing through the optical system 117 into an elliptic shape. Detailed description thereof will be omitted.

In addition, in the present embodiment, a laser processing apparatus having two laser beam generating means has been described. However, if necessary, one laser beam generating means may be used, and in this case, a laser beam emitted from the laser beam generating means is beamed. It can be used by dividing by a splitter and entering the beam splitting means, respectively.

FIG. 28 is a diagram illustrating a first modification of the laser processing apparatus shown in FIG. 27.

The laser processing apparatus shown in FIG. 28 shows the case where the polygon mirror 151 is applied as a reflection mirror.

In this embodiment, the polygon mirror 151 has a plurality of reflective surfaces 153 and rotates about the rotation axis 152, and the driver 107 uses the motor (not shown) to rotate the polygon mirror 151. Rotate at constant speed at the preset speed.

Each laser beam reflected from the first and second mirrors 145-1 and 145-2 is incident and reflected on the reflecting surface 153 of the polygon mirror 151, and then is staged through the optical system 117. ) Is irradiated to the object 119, and the specific operation principle is the same as in FIG.

In the present embodiment, it is preferable to use two laser generating means 139-1 and 139-2, but only one may be used if necessary. When only one laser generating means is used, the laser beam is divided into two using a beam splitter.

In addition, the laser processing apparatus according to the present embodiment may also further include at least two beam forming parts for converting the cross section of the laser beam passing through the optical system 117 into an elliptical shape.

Meanwhile, although not shown, the reflection mirror of FIG. 27 may be configured as AOD, in which case the driver 107 should be replaced by a high frequency driver.

FIG. 29 is a second modified example of the laser processing apparatus illustrated in FIG. 27.

The laser processing apparatus according to the present embodiment includes a control unit 101 for controlling the overall operation, at least two laser generating means 139-1 and 139-2 for outputting a laser beam having a specified aperture, and a laser generating means 139 At least two beam splitting means (141-1, 141-2) and polygon mirrors (155-1, 155-2), each of which receives the laser beams emitted from -1, 139-2, and splits them into at least two A driver 107 for driving, an input unit 109 for inputting control parameters and control commands, an output unit 111 for displaying information such as an operating state, a storage unit 113 for storing data, and a plurality of reflective surfaces (153-1, 153-3), reflected from at least two polygon mirrors (155-1, 155-2), polygon mirrors (155-1, 155-2) rotated symmetrically about a rotation axis Reflected by at least two reflecting mirrors 157-1 and 157-2 and reflecting mirrors 157-1 and 157-2, respectively reflecting the laser beam. An optical system 117 for condensing an edger beam, and during the processing of the object 119, stage transfer means for transferring the stage 121 on which the object 119 is seated at least once in a direction opposite to the irradiation direction of the laser beam; 123 may be further included. Here, the optical system 117 may be implemented as a condenser lens.

The pair of polygon mirrors 155-1 and 155-2 are installed in a horizontal direction with the stage 121 on which the object 119 to be processed is mounted, and the reflection mirrors 157-1 and 157-2 are polygon mirrors. And a laser beam reflected between the reflecting surfaces 153-1 and 153-2 of the polygon mirrors 155-1 and 155-2 to be reflected toward the optical system 117. The reflection mirrors 157-1 and 157-2 are installed at an angle so as to face each other in the vertical direction with respect to the stage 121.

In this case, the optical system 117 is installed in a horizontal direction with the stage 121 on which the object 119 to be processed is mounted and collects the laser beams reflected from the reflection mirrors 157-1 and 157-2. In addition, the inclination of the reflective mirrors 157-1 and 157-2 can adjust the distance between the pair of laser beams scanned perpendicular to the object 119. That is, as the reflection mirrors 157-1 and 157-1 are tilted more with respect to the vertical direction of the stage 121, the interval between the laser beams scanned on the object 119 becomes narrower and the reflection mirrors 157-1 and 157 The smaller the angle -2) with respect to the vertical direction of the stage 121, the wider the interval between the laser beams scanned on the object 119 is.

According to the laser processing apparatus according to the present embodiment, the laser beams generated by the two laser generating means 139-1 and 139-2 under the control of the controller 101 are respectively formed of the first polygon mirror 155-1 and the first polygon mirror 155-1. 2 is incident on the polygon mirror 155-2. The laser beams incident on the polygon mirrors 155-1 and 155-2 are rotated symmetrically by the driver 107, and the first polygon mirrors 155 on the respective reflecting surfaces 153-1 and 153-2. -1) and the second polygon mirror 155-2 are respectively reflected in the directions of the first mirror 157-1 and the second mirror 157-2. The laser beams reflected by the first mirror 157-1 and the second mirror 157-2 are formed with the first mirror 157-1 and the first mirror 157-1 inclined at a predetermined angle in a direction opposite to the direction of the stage 121. It is reflected by the two mirrors 157-2 in the direction of the optical system 117. The laser beams reflected by the first mirror 157-1 and the second mirror 157-2 are respectively focused by the optical system 117 and irradiated to the object 119 in the vertical direction.

FIG. 30 is a third modified example of the laser processing apparatus illustrated in FIG. 27.

The laser processing apparatus according to the present embodiment uses one laser generating means and a beam splitting means, and divides the laser beam output from the beam splitting means by the beam splitter 159 to simultaneously process multiple lines. to be.

That is, the laser beam emitted from the laser generating means 103 is divided into at least two or more in the beam splitting means 105, and the laser beam emitted from the beam splitting means 105 is divided into two in the beam splitter 159, respectively. The laser beams transmitted through the beam splitter 159 are incident to the first polygon mirror 155-1, and the laser beams reflected from the beam splitter 159 are incident to the second polygon mirror 155-2.

Subsequently, the process of the laser beam through the first and second polygon mirrors 155-1 and 155-2, the reflection mirrors 157-1 and 157-2, and the optical system 117 is the same as that described with reference to FIG. 29. Detailed description will be omitted.

According to the fifth embodiment of the present invention, the laser beams are reflected at different positions and collected, and then irradiated onto the object, thereby processing a plurality of processing sites through a single processing process.

In addition, the laser processing apparatus shown in FIGS. 29 and 30 may include at least two beam forming portions for forming the elliptical shape of the cross-sectional shape of the laser beam passing through the optical system 117, in which case by-product discharge from the processing surface This becomes easy and can increase processing efficiency.

In addition, the polygon mirrors of FIGS. 29 and 30 may be replaced with AOD, in which case the driver 107 should be replaced with a high frequency driver.

Laser processing method by laser beam splitting and stage feeding

31 is a flowchart for explaining a laser processing method according to a first embodiment of the present invention. The laser processing method according to the present embodiment is, for example, in FIGS. 1, 9, 14, 16, or 20. It can be applied when using the laser processing apparatus shown.

First, the rotational speed of the beam scanner 115, the feed rate of the stage transfer means 123, the processing time, the frequency of the laser beam, and the laser, depending on the type and processing purpose of the object 119 to be processed through the input unit 109. Control parameters such as power of the beam are set (S101). This setting process can be made simply by registering as a menu set in advance according to the type of object and processing purpose, storing it in the storage unit 113, and calling the menu.

When the setting of the control parameter is completed, the beam scanner 115 (or polygon mirror 115-1) is driven by the driver 107 (S103), and the stage 121 is driven by driving the stage transfer means 123. It is made to transfer in the specified direction (direction opposite to the irradiation direction of the laser beam) (S105).

Then, when the laser beam is emitted from the laser generating means 103 (S107), the emitted laser beam is incident to the beam splitter 105 to be split into at least two (S109), each divided laser beam is The light is reflected by the beam scanner 115 (or the polygon mirror 115-1) and collected by the optical system 117, and then irradiated onto the object 119 to process the object (S111).

In this embodiment, the laser beam is divided into a plurality of parts to reduce the processing line width, while maintaining the intensity of the laser beam, and the processing speed is improved by moving the stage in a direction opposite to the direction in which the laser beam is irradiated to the object. You can.

In addition, when the present invention is applied to a laser processing apparatus using a polygon mirror, the laser beam is irradiated onto the object 119 in accordance with the rotation of the polygon mirror can further improve the processing efficiency.

Laser processing method through error correction of polygon mirror

32 is a flowchart for explaining the laser processing method according to the second embodiment of the present invention, and can be applied, for example, when using the laser processing apparatus shown in FIG.

First, the test object is seated on the stage 121, and then the polygon mirror 115-1 is driven by the driver 107, while the laser beam emitted by the laser generating means 103 receives the beam beam splitting means 105. The image is divided into and irradiated to the reflection surface of the polygon mirror 115-1 (S201). After machining the test object by rotating the polygon mirror 155-1 at least once in this manner, the error on each reflecting surface of the polygon mirror is measured using the result of the test object processing, and the error is reported. Input to the step 125 to calculate the error correction value, that is, the incident angle adjustment value of the laser beam on each reflective surface of the polygon mirror (S203).

In this way, in order to process the actual object after calculating the error compensation value at each reflection surface of the polygon mirror 115-1, the control parameter (rotation of the polygon mirror) according to the object to be processed through the input unit 109 Speed, stage feed speed, processing time, output intensity / frequency of the laser beam, etc.) are set (S205). Such a setting process can be easily performed by registering a preset menu according to the type and processing type (cutting, grooving, etc.) of the object to be processed, storing it in the storage unit 113, and calling the menu.

When the setting of the control parameter is completed, the driver 107 is controlled to rotate the polygon mirror 115-1 at a constant speed according to the preset rotational speed and simultaneously drive the actuator 200 (S207), and the stage feed means 123. ) To transfer the stage 121 at a preset speed (S209).

Accordingly, a polygon mirror (S211) emitted from the laser generating means (103) and divided into at least two or more laser beams from the beam splitting means (105) through the mirror (202) mounted on the actuator (200). The laser beam incident on the reflective surface of 115-1 and reflected on the reflective surface of the polygon mirror 115-1 is focused on the optical system 117 and then irradiated onto the object 119 (S215).

When the laser beam emitted from the laser generating means 103 is irradiated to the mirror 202 after being split by the beam dividing means 105, the control unit 101 calculates an error compensation value previously calculated by the error correcting unit 125. By driving the actuator 200 with reference to the direction of the mirror 202, the laser beam is always removed from the polygon mirror by changing the angle of incidence of the laser beam at the polygon mirror reflecting surface where an error exists. Make it reflect at the same angle.

Laser processing method by laser beam splitting and object cooling

33 is a flowchart for explaining the laser processing method according to the third embodiment of the present invention, and can be applied, for example, when using the laser processing apparatus shown in FIG.

In order to process the object, the stage 121 on which the object 119 is seated is loaded into the chamber 500. In addition, the control parameter according to the object to be processed is set (S301). This setting process can be easily performed by registering a preset menu according to the type of object to be processed, the processing form, and storing the same in the storage unit 113 and calling the menu.

When the control parameter setting is completed, the thermoelectric element 502 is driven to cool the object 119, and thus, an ice layer 135 is formed on the surface of the object 119 (S303). Although the object 119 may be started by the thermoelectric element 502 after being loaded into the chamber 500, the object 119 may be loaded into the chamber 500 in a pre-cooled state to shorten the cooling time. At this time, as described above, in order to prevent the water condensed between the object 119 and the stage 121 is cooled, it is preferable to precool to a temperature higher than the freezing point.

In addition, in order to solve that the ice layer 135 formed on the surface of the object 119 is opaque and the surface of the object 119 is hardly observed, the ice layer 510 is partially melted and then recooled. As a result, a transparent freezing layer 135 is obtained. When melting the freezing layer 135 may be a non-contact method of evenly spraying a heated metal plate on the surface of the freezing layer 135 or evenly spraying hot air on the surface of the freezing layer 135.

In addition, when the humidity in the chamber 500 sensed by the sensor 508 is lower than the specified value, the moisture is supplied into the chamber 500 through the humidifying means 506 to form a freezing layer 135 having a sufficient thickness.

Subsequently, the beam scanner 115 is driven by the driver 107 (S305), and the stage transporting means 123 is driven to transport the stage 121 at a predetermined speed (S307), and the laser generating means ( 103, the laser beam is emitted by controlling (S309).

Accordingly, the laser beam emitted from the laser generating means 103 is divided into at least two by the beam splitting means 105 (S311), the divided laser beam is transmitted through the beam scanner 115 and the optical system 177 The object 119 is irradiated and processed (S313).

After the processing is completed, a cleaning process for removing the frozen layer 135 and the particles generated during the processing on the object 119 is performed (S315). The washing process may be wet or dry. Wet cleaning is a method of removing the particles attached to the surface of the freezing layer 135 together with the freezing layer 135 using water, and dry cleaning sprays gas (hot air) onto the surface of the freezing layer 135 to freeze. It is a method of removing the particles on the surface of the freezing layer 135 while melting the layer 135. As a result of the cleaning process, water in which the frozen layer is dissolved can be obtained, which contains particles. These particles can be recovered separately through a filter, thereby preventing the generation of industrial wastewater.

In this way, when the processing and cleaning of the object is completed, the object is unloaded from the chamber so that the subsequent process can be performed.

Method of processing object with multi-layer

The object to be processed using a laser may be formed of a single layer, but may be formed of a plurality of layers. If an object formed of a plurality of layers is processed under the same processing conditions, lifting, explosion, etc. may occur at the boundary of each layer. Can be.

That is, since each layer has its own optical, physical, and chemical properties, it is necessary to adjust the processing parameters according to the properties of each layer to process the object. Therefore, when processing the object by changing the processing parameters for each layer when processing the object consisting of a multi-layer can improve the processing efficiency, it is possible to prevent the propagation effect of cracks generated during the object processing.

34 is a flowchart for explaining a laser processing method according to a fourth embodiment of the present invention, and is a view for explaining a method for processing an object having multiple layers.

First, to set the machining parameters for each layer of the object (S401), the machining parameters to be set in advance, the laser output power, the rotational speed of the mirror (mirror or polygon mirror or AOD of the beam scanner), the stage feed speed at which the object is seated, The irradiation frequency of the laser beam, the focus position of the laser beam, and the like may be included.

After setting the processing parameters for each layer, the laser processing apparatus using the mirror is driven to process the exposed layer of the object (S403). When the machining of the exposed upper layer of the machining site is completed, it is checked whether the machining of all the layers of the object is performed (S405), and when the machining of all the layers is completed, the process is terminated. If there is a layer to be left, the flow returns to step S403.

Here, the process of processing the exposed layer of the object (S403) will be described in detail. First, the beam scanner (or polygon mirror or AOD) is driven (S4031), and the stage on which the object is mounted is transferred (S4033). At this time, the stage is preferably conveyed in the direction opposite to the processing direction. Thereafter, the laser beam is emitted (S4035), the emitted laser beam is divided into a plurality of beam splitters (S4037), and then reflected on the reflective surface of the beam scanner (or polygon mirror or AOD) to the object through the optical system. To be investigated.

As described above, in the present invention, when processing an object composed of multiple layers, the processing parameters are optimized and set for each layer, and the processing is performed by different processing parameters for each layer, so that the lifting and explosion at the layer boundary is performed. It can be prevented from occurring.

FIG. 35 is a flowchart for explaining an embodiment of an object machining process illustrated in FIG. 34.

The object processing method according to the present embodiment includes a scribing step (S501) and a laser cutting step (S503).

When the object formed by multiple layers is directly processed by laser, cracks may occur due to the characteristic difference between the layers, and manufacturing yield is deteriorated when the cracks are propagated to the active region (chip region). After scribing both edge portions of the entire machining area, cutting by laser machining can reduce the crack incidence.

36A and 36B are views for explaining an example in which an object is processed according to the processing described with reference to FIG. 35.

As shown in FIG. 36A, for example, after the active regions 220 and 24 are formed on the semiconductor substrate 20, a cutting process for separating the active regions is performed. The edge portion 26 of the machining region is machined by the.

Thereafter, as shown in Fig. 36B, the processing region is removed using a laser processing apparatus. Here, when the semiconductor substrate 20 of a process area is formed in multiple layers, it is preferable to process the semiconductor substrate 20 by the processing parameter set differently for each layer as demonstrated in FIG.

In addition, in the present embodiment, the scribing process may also be performed by the laser processing apparatus.

Although not shown, after performing the cutting process (S503), when the healing process is performed, cracks generated in the cutting process using a laser can be effectively removed.

37 is a flowchart for explaining another embodiment of the object processing process shown in FIG. 34.

In the case of laser processing an object formed of multiple layers, cracks may be generated in the processing site and propagate to the active area. In order to prevent this, in the present embodiment, after cutting the object (S601), the cutting part is healing (Healing). S603).

More specifically, first, the processing region is cut using a laser processing apparatus. At this time, when the object to be processed is formed of multiple layers, it is preferable to process the object by processing parameters set differently for each layer using the processing method described in FIG.

Since a crack may occur in the processing site by such a cutting process, the healing process is subsequently performed to increase the processing efficiency by allowing the crack parts to be bonded again.

38A and 38B are views for explaining an example in which an object is processed according to the processing described with reference to FIG. 37.

Referring to FIG. 38A, when laser processing the semiconductor substrate 20 on which the active regions 22 and 24 are formed, it can be seen that a crack 28 has occurred in the processing portion of the semiconductor substrate 20.

In this case, when the healing process is performed as shown in FIG. 38B, the crack part is bonded. For example, in the case of a silicon (Si) substrate, the substrate is changed to silicon dioxide (SiO ₂ ) by a healing process to bond cracks, thereby preventing propagation of the cracks into the active region.

In summary, the present embodiment sets machining parameters differently for each layer before processing an object formed of multiple layers, and sequentially processes each layer, thereby improving processing reliability and improving die strength. Can be.

In addition, by using the polygon mirror to scribe the edge portion of the machined portion before performing the multi-machining, it is possible to prepare for the crack phenomenon occurring during laser processing, if the crack occurs by joining the crack portion by the healing process Cracks can be prevented from propagating.

Laser processing method for simultaneous processing of multiple processing lines

39 is a flowchart for explaining the laser processing method according to the fifth embodiment of the present invention, and can be achieved by, for example, the laser processing apparatus shown in FIG.

First, the inclination and position of the actuators 143-1 and 143-2, the rotational speed of the reflection mirror 147, and the object 19 are seated according to the object 119 to be processed through the input unit 109. Control parameters such as the feed rate of the stage 121 are set (S701). This setting process can be made simply by registering as a preset menu according to the type and processing type of the object 119 to be processed and storing it in the storage unit 113 and calling the menu.

When the setting is completed, the controller 101 controls the first actuator 143-1 and the second actuator 143-2 to set the first mirror 145-1 and the second mirror 145-2, respectively. Adjust the tilt angle and position according to (S703), and controls the driver 107 to repeatedly rotate the reflection mirror 147 within a predetermined angle range at a predetermined rotation speed (S705), the stage feed means 123 In operation S707, the stage 121 is driven at a set speed. At this time, the control unit 101 controls the two laser generating means (139-1, 139-2) to emit a laser beam (S709).

Thereafter, the emitted laser beam is divided into at least two or more in the first and second beam splitters 141-1 and 141-2, respectively (S711), and then the first mirror 145-1 and the second mirror, respectively. Incident at 145-2. The laser beams incident on the mirrors 145-1 and 145-2 are reflected by the mirrors 145-1 and 145-2 and are incident at the same positions of the reflection mirrors 147 in different directions. Each laser beam incident on the reflecting mirror 147 is focused on the optical system 117 through the reflecting surface of the rotating reflecting mirror 147, and then irradiated perpendicularly to the object 119. In this way, it is possible to process a plurality of processing lines at the same time (S713).

In the above-described process, since the reflection mirror 147 rotates at a constant speed, the scanning length of the laser beam described above overlaps a predetermined number of times and is irradiated onto the object 119.

In addition, when the stage 121 on which the object 119 is seated is transferred in a reverse direction with respect to the rotation direction of the reflection mirror 147, the relative speed at which the laser beam irradiated to the object 119 irradiates the scanning length is faster. The object 119 is smoothly processed.

In the laser processing methods of FIGS. 31 to 34 and 29 described above, when the laser beam is irradiated to the object through the beam forming part after passing through the optical system, the shape of the beam irradiated to the object will be an ellipse, in which case the laser By-products generated during processing the used object can be effectively discharged, thereby increasing the processing efficiency.

As such, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof. Therefore, the above-described embodiments are to be understood as illustrative in all respects and not as restrictive. The scope of the present invention is shown by the following claims rather than the detailed 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.

According to the present invention, by processing the object by dividing the laser beam into two or more, it is possible to obtain the effect of processing the object a plurality of times with a laser beam having a low energy to ensure a narrow line width, the laser beam divided into a plurality At the same time, because the object is irradiated, high processing speed can be guaranteed.

In addition, by moving the stage in a direction opposite to the direction in which the laser beam is irradiated to the object, it is possible to further improve the object processing speed.

In addition, by adjusting the laser beam to an elliptic shape to process the object, by-products generated during the object processing to be discharged to the outside, it is possible to prevent the by-products re-deposited on the object to be processed, thereby improving the reliability of the chip in the subsequent process Can be improved.

Further, by introducing a mask for filtering the laser beam emitted from the mirror rotation return point of the laser beam emitted from the beam scanner, it is possible to prevent the object from being uniformly processed by the laser beam irradiated from the mirror rotation return point of the beam scanner. Can be.

In addition, when the object is processed by forming an ice layer on the surface of the object through a thermoelectric element or a cooling stage, the object may be processed without forming a separate coating layer, and the cost required for the cleaning process after the object is reduced, Particles generated during laser processing can be easily recovered in the cleaning process to solve the environmental pollution problem.

On the other hand, it is possible to process a plurality of processing sites at the same time by using a plurality of laser generating means, thereby improving processing speed and performance.

In addition, when processing the object consisting of a plurality of layers, the processing parameters are set differently according to the properties of each layer, and the processing can be performed to minimize the occurrence of cracks in the object during laser processing, even when a crack occurs Crack propagation can be prevented by the process, and the yield and reliability of the device can be greatly improved.

Claims (94)

A laser processing apparatus for processing an object by irradiating a laser beam emitted from the laser generating means to the object, Beam dividing means for dividing the laser beam emitted from the laser generating means into at least two or more; A beam scanner that receives the laser beam split by the beam splitter and reflects the laser beam repeatedly to be scanned at the processing position of the object; And Stage processing means for transferring the stage on which the object is to be seated, at least once, in a direction opposite to the direction in which the laser beam is irradiated, while processing the object; Laser processing apparatus comprising a. The method of claim 1, The laser processing apparatus includes an optical system for condensing each laser beam reflected from the beam scanner; And At least two beam forming parts for shaping a cross section of each laser beam passing through the optical system and irradiating the object; Laser processing apparatus further comprising a. The method of claim 2, The beam shaping unit may include a first lens configured to transform the laser beam into cross-section light; And A second lens installed to be perpendicular to the first lens and transmitting the cross-sectional light transmitted from the first lens in an elliptical shape; And a position of the first lens up and down to adjust the size of the elliptical laser beam transmitted from the second lens. The method of claim 3, wherein The said 1st lens and the 2nd lens are each a cylindrical lens, The laser processing apparatus characterized by the above-mentioned. The method of claim 3, wherein And processing the object by aligning the processing direction of the object and the long axis of the elliptical laser beam to coincide. The method according to claim 3 or 5, The size of the elliptical laser beam is a laser processing apparatus, characterized in that the length ratio of the short axis and the long axis is 1: 4 to 1:12. The method of claim 1, And said beam splitting means comprises a prism for dividing the incident laser beam into two. The method of claim 1, And said beam splitting means comprises a beam splitter for dividing an incident laser beam into two. The method of claim 1, And the beam splitting means comprises a beam splitter for dividing the incident laser beam into two and a prism for dividing any one of the laser beam divided into two at the beam splitter. The method of claim 1, And said beam splitting means comprises a prism for dividing the incident laser beam into two and a beam splitter for dividing the laser beam divided into two in said prism. The method of claim 1, The beam splitting means comprises: a first mirror for reflecting an incident laser beam; A prism that divides the laser beam reflected from the first mirror into two; And A second mirror for reflecting the beam split in the prism; Laser processing apparatus comprising a. The method of claim 1, The beam splitting means comprises: a beam splitter for dividing an incident laser beam into two; A polarizer for converting polarization characteristics of the first laser beam reflected by the beam splitter; A first mirror for reflecting a second laser beam transmitted through the beam splitter; A second mirror for reflecting the second laser beam reflected from the first mirror; And A polarizing beam splitter for reflecting the first laser beam whose polarization characteristic is converted in the polarizer and transmitting the second laser beam reflected by the second mirror; Laser processing apparatus comprising a. The method of claim 1, The beam splitting means comprises: a beam splitter for dividing an incident laser beam into two; A polarizer for converting polarization characteristics of the laser beam reflected by the beam splitter; A prism for dividing the laser beam polarized by the polarizer into first and second laser beams; A first mirror for reflecting a third laser beam that has passed through the beam splitter; A second mirror for reflecting a third laser beam reflected from the first mirror; And A polarizing beam splitter for reflecting first and second laser beams emitted from the prism and transmitting a third laser beam incident through the second mirror; Laser processing apparatus comprising a. The method of claim 1, The beam splitting means includes a prism for dividing an incident laser beam into two; A beam splitter for splitting and dividing the two beams divided by the prism into two beams; A polarizer for converting polarization characteristics of the first and second laser beams reflected by the beam splitter; A first mirror for reflecting third and fourth laser beams transmitted by the beam splitter; A second mirror for reflecting the laser beam reflected from the first mirror; And A polarization beam splitter for reflecting the first and second laser beams whose polarization characteristics are changed in the polarizer and transmitting the third and fourth laser beams incident through the second mirror; Laser processing apparatus comprising a. The method of claim 1, The beam scanner is any one of a reflecting apparatus using a galvanometer scanner or a servo motor. The method of claim 1, The laser processing apparatus further includes a driver, The beam scanner includes one or two motors driven by the driver; And First and second mirrors connected to the rotation shafts of the motor to repeat the rotation according to a specified angle and direction; Including; Wherein the first mirror reflects the laser beam reflected from the beam splitter and exits the second mirror, and the second mirror irradiates the laser beam incident by the first mirror to the object. Laser processing device. The method of claim 1, The laser processing apparatus further includes a driver, And the beam scanner is a polygon mirror having a plurality of reflecting surfaces and rotating at a predetermined angular velocity about the rotation axis by the driver. The method of claim 17, According to the rotation of the polygon mirror, the scanning length of the laser beam irradiated to the object by one reflective surface is adjusted by the product of the focal length of the optical system and the angle of the laser beam reflected from the reflective surface of the polygon mirror. Laser processing device made. The method of claim 18, The angle of the laser beam is a laser processing apparatus, characterized in that the angle formed by the laser beam reflected at the start and end of the reflective surface. The method of claim 17, The laser beam reflected from the reflective surface is irradiated onto the object a predetermined number of times as the polygon mirror is rotated, and the angular velocity of the polygon mirror is controlled by controlling the angular number of times while maintaining a constant feeding speed of the stage. Laser processing apparatus characterized in that. The method of claim 17, The laser processing apparatus includes: an encoder mounted to the polygon mirror to convert position and velocity information of the polygon mirror into an electrical signal and output the electrical signal; An error correction unit configured to receive an error value for each reflective surface of the polygon mirror and calculate an error compensation value at each reflective surface; And The laser beam received from the encoder and reflecting surface information of the polygon mirror, driving the mirror with reference to the error compensation value for each reflecting surface, and is output from the beam splitting means and incident on the reflecting surface of the polygon mirror An actuator for changing the incident direction of the; Laser processing apparatus further comprising a. The method of claim 21, The encoder is a laser processing apparatus, characterized in that the rotary encoder. The method of claim 17, The polygon mirror is characterized in that the number of the reflecting surface is controlled to be produced so that when each laser beam incident from the beam splitting means is incident on the reflecting surface of the polygon mirror, incident to the plurality of reflecting surfaces at the same time Laser processing device. The method of claim 23, The radius of the polygon mirror circumscribed circle is R, the diameter of the laser beam is D, the vertical distance from the rotation axis to the center of the laser beam incident on the polygon mirror is h, and the laser is incident on one reflective surface of the polygon mirror. The energy of the entire beam is attenuated and the loss angle of the incident laser beam

, When the number of reflecting surfaces of the polygon mirror is N, the loss ratio at one reflecting surface of the polygon mirror

When I say Laser processing apparatus, characterized in that the number of reflecting surface (N) of the polygon mirror is implemented so that the loss rate is 100% or more. The method of claim 1, The laser processing apparatus further includes a high frequency driver, And the beam scanner is an acoustic-optical deflector that irradiates the object with at least two laser beams input from the beam splitting means in response to a high frequency signal from the high frequency driver. The method of claim 25, The high frequency driver inputs two high frequency signals to the acousto-optic deflector, and the acousto-optic deflector outputs the laser beam to rotate between scanning angles determined according to the frequency of the high frequency signal input through the high frequency driver. Laser processing apparatus characterized in that. The method of claim 1, The laser processing apparatus includes an optical system for condensing a laser beam reflected from the beam scanner; And And a mask including a hole for filtering the laser beam emitted from the rotational return point of the beam scanner before the laser beam emitted from the beam scanner enters the optical system. The method of claim 1, The laser processing apparatus includes an optical system for condensing a laser beam reflected from the beam scanner; And And a mask including a hole for filtering the laser beam emitted from the rotational return point of the beam scanner before the laser beam emitted from the optical system is irradiated to the object. The method of claim 27 or 28, And said mask is made of metal. The method of claim 1, The laser processing apparatus is installed on the rear surface of the stage to cool the object through the stage, and condensation on the surface of the object by condensation of water vapor due to a temperature difference between the temperature in the object chamber and the object in which the object is loaded. A thermoelectric element which generates and forms a freezing layer as a coating on the surface of the object by continuing cooling; And Heat insulation means provided on the rear surface of the thermoelectric element; Laser processing apparatus further comprising a. The method of claim 30, The laser processing apparatus further comprises a sensor for measuring the temperature and humidity in the processing chamber. The method of claim 31, wherein The laser processing apparatus further comprises humidifying means for supplying water vapor into the chamber when the humidity in the processing chamber is lower than a specified value according to the measurement result of the sensor. The method of claim 30, The laser processing apparatus further comprises a thawing means for melting a part of the freezing layer, wherein the freezing layer on the surface of the object is recooled to a transparent state by the thermoelectric element. The method of claim 33, wherein The means for thawing, the laser processing apparatus, characterized in that implemented in contact or non-contact. The method of claim 34, wherein And said contact thawing means is a heatable metal plate, and said non-contact thawing means is a heater coil for receiving and heating water vapor. The method of claim 30, And the object is precooled to a temperature above the condensation point before being loaded into the processing chamber. The method of claim 1, The stage may include a body portion having a plurality of vacuum holes on which an object is mounted; A vacuum part disposed on a rear surface of the body part and having a vacuum tube path for sucking air along the vacuum hole; And A cooling unit disposed on a rear surface of the vacuum unit to discharge heat accumulated in the body unit; Laser processing apparatus comprising a. The method of claim 37, wherein The cooling unit, a thermoelectric element having a thermoelectric element for cooling the heat generated from the body portion by adjusting the transfer direction of heat; And A cooling conduit part installed on a rear surface of the thermoelectric element part to circulate a refrigerant to cool the thermoelectric element part; Laser processing apparatus comprising a. The method of claim 37, wherein The stage further comprises a temperature sensor for sensing the temperature of the body portion, wherein the cooling unit is on / off according to the temperature sensing result of the temperature sensor laser processing apparatus. The method of claim 37, wherein The body portion is a laser processing apparatus, characterized in that made of any one material of quartz, porous glass, silver ceramic, uneven stone. The method of claim 37, wherein The vacuum pressure of the vacuum unit is a laser processing apparatus, characterized in that 50kpa to 80kpa. The method of claim 38, The refrigerant is a laser processing apparatus, characterized in that any one of water, water and ethylene glycol mixture, air, cooling gas, cooling liquid. A laser processing apparatus for processing an object using a laser, A plurality of laser generating means for emitting a laser beam; A plurality of beam splitting means for receiving the respective laser beams emitted from the plurality of laser generating means and splitting them into at least two; A plurality of mirrors each receiving a laser beam split by the beam splitting means and reflecting the same to a same position; An actuator installed at each of the plurality of mirrors to adjust an angle and a position of the mirror; A reflection mirror which receives and reflects a laser beam reflected from each of the plurality of mirrors; And An optical system for condensing a laser beam reflected by the reflection mirror and irradiating the object to the object; Laser processing apparatus comprising a. A laser processing apparatus for processing an object using a laser, A plurality of laser generating means for emitting a laser beam; A plurality of beam splitting means for receiving the respective laser beams emitted from the plurality of laser generating means and splitting them into at least two; A plurality of polygon mirrors having a plurality of reflecting surfaces and rotating about a rotation axis, the plurality of polygon mirrors receiving and reflecting laser beams divided by the beam splitting means; A plurality of reflection mirrors each reflecting a laser beam reflected from each of the plurality of polygon mirrors; And An optical system for condensing a laser beam reflected by the reflection mirror and irradiating the object to the object; Laser processing apparatus comprising a. A laser processing apparatus for processing an object using a laser, Laser generating means for emitting a laser beam; A plurality of beam splitting means for receiving the laser beam radiated from the laser generating means and dividing the beam into at least two; A beam splitter for splitting each laser beam split by the beam splitting means into at least two; A plurality of mirrors each receiving and reflecting a laser beam transmitted or reflected by the beam splitter; A plurality of reflection mirrors each reflecting a laser beam reflected from each of the plurality of mirrors; And An optical system for condensing a laser beam reflected by the reflection mirror and irradiating the object to the object; Laser processing apparatus comprising a. The method of any one of claims 43-45, The laser processing apparatus further includes a stage transfer means for transferring the stage on which the object is to be seated, at least once, in a direction opposite to the direction in which the laser beam is irradiated, while processing the object. The method of claim 43, The said reflection mirror is a laser processing apparatus characterized by the above-mentioned. The method of claim 45, Each of the plurality of mirrors is a polygon mirror, characterized in that the laser processing apparatus. 49. The method of claim 47 or 48, According to the rotation of the polygon mirror, the scanning length of the laser beam irradiated to the object by one reflective surface is adjusted by the product of the focal length of the optical system and the angle of the laser beam reflected from the reflective surface of the polygon mirror. Laser processing device made. 49. The method of claim 47 or 48, The laser beam reflected from the reflecting surface is irradiated to the object a predetermined number of times as the polygon mirror is rotated, and the overlap count is controlled by adjusting the angular velocity of the polygon mirror while maintaining a constant feeding speed of the stage. Laser processing apparatus characterized in that. 49. The method of claim 47 or 48, The laser processing apparatus includes: an encoder mounted to the polygon mirror to convert position and velocity information of the polygon mirror into an electrical signal and output the electrical signal; An error correction unit configured to receive an error value for each reflective surface of the polygon mirror and calculate an error compensation value at each reflective surface; And The laser beam received from the encoder and reflecting surface information of the polygon mirror, driving the mirror with reference to the error compensation value for each reflecting surface, and is output from the beam splitting means and incident on the reflecting surface of the polygon mirror An actuator for changing the incident direction of the; Laser processing apparatus further comprising a. The method of claim 51 wherein The encoder is a laser processing apparatus, characterized in that the rotary encoder. 49. The method of claim 47 or 48, The polygon mirror is characterized in that the number of the reflecting surface is controlled to be produced so that when each laser beam incident from the beam splitting means is incident on the reflecting surface of the polygon mirror, incident to the plurality of reflecting surfaces at the same time Laser processing device. The method of claim 53 wherein The radius of the polygon mirror circumscribed circle is R, the diameter of the laser beam is D, the vertical distance from the rotation axis to the center of the laser beam incident to the polygon mirror is h, and the laser is incident on one reflective surface of the polygon mirror. The energy of the entire beam is attenuated and the loss angle of the incident laser beam

, When the number of reflecting surfaces of the polygon mirror is N, the loss ratio at one reflecting surface of the polygon mirror

When I say Laser processing apparatus, characterized in that the number of reflecting surface (N) of the polygon mirror is implemented so that the loss rate is 100% or more. The method of any one of claims 43-45, The laser processing apparatus further comprises at least a plurality of beam forming portions for shaping a cross section of each laser beam that has passed through the optical system and irradiating the object. The method of claim 55, The beam shaping unit may include a first lens configured to transform the laser beam into cross-section light; And A second lens installed to be perpendicular to the first lens and transmitting the cross-sectional light transmitted from the first lens in an elliptical shape; And a position of the first lens up and down to adjust the size of the elliptical laser beam transmitted from the second lens. The method of claim 56, wherein The said 1st lens and the 2nd lens are each a cylindrical lens, The laser processing apparatus characterized by the above-mentioned. The method of claim 54, wherein The laser processing apparatus is arranged so that the machining direction of the object and the long axis of the elliptical laser beam are aligned to process the object. The method of claim 54, wherein The size of the elliptical laser beam is a laser processing apparatus, characterized in that the length ratio of the short axis and the long axis is 1: 4 to 1:12. The method of any one of claims 43-45, And said beam splitting means comprises a prism for dividing the incident laser beam into two. The method of any one of claims 43-45, And said beam splitting means comprises a beam splitter for dividing an incident laser beam into two. The method of any one of claims 43-45, And the beam splitting means comprises a beam splitter for dividing the incident laser beam into two and a prism for dividing any one of the laser beam divided into two at the beam splitter. The method of any one of claims 43-45, And said beam splitting means comprises a prism for dividing the incident laser beam into two and a beam splitter for dividing the laser beam divided into two in said prism. The method of any one of claims 43-45, The beam splitting means comprises: a first mirror for reflecting an incident laser beam; A prism that divides the laser beam reflected from the first mirror into two; And A second mirror for reflecting the beam split in the prism; Laser processing apparatus comprising a. The method of any one of claims 43-45, The beam splitting means comprises: a beam splitter for dividing an incident laser beam into two; A polarizer for converting polarization characteristics of the first laser beam reflected by the beam splitter; A first mirror for reflecting a second laser beam transmitted through the beam splitter; A second mirror for reflecting the second laser beam reflected from the first mirror; And A polarizing beam splitter for reflecting the first laser beam whose polarization characteristic is converted in the polarizer and transmitting the second laser beam reflected by the second mirror; Laser processing apparatus comprising a. The method of any one of claims 43-45, The beam splitting means comprises: a beam splitter for dividing an incident laser beam into two; A polarizer for converting polarization characteristics of the laser beam reflected by the beam splitter; A prism for dividing the laser beam polarized by the polarizer into first and second laser beams; A first mirror for reflecting a third laser beam that has passed through the beam splitter; A second mirror for reflecting a third laser beam reflected from the first mirror; And A polarizing beam splitter for reflecting first and second laser beams emitted from the prism and transmitting a third laser beam incident through the second mirror; Laser processing apparatus comprising a. The method of any one of claims 43-45, The beam splitting means includes a prism for dividing an incident laser beam into two; A beam splitter for splitting and dividing the two beams divided by the prism into two beams; A polarizer for converting polarization characteristics of the first and second laser beams reflected by the beam splitter; A first mirror for reflecting third and fourth laser beams transmitted by the beam splitter; A second mirror for reflecting the laser beam reflected from the first mirror; And A polarization beam splitter for reflecting the first and second laser beams whose polarization characteristics are changed in the polarizer and transmitting the third and fourth laser beams incident through the second mirror; Laser processing apparatus comprising a. The method of any one of claims 43-45, The laser processing apparatus further includes a high frequency driver, And the reflection mirror is an acoustic-optical deflector that reflects a plurality of laser beams input from each of the plurality of mirrors to the optical system in response to a high frequency signal from the high frequency driver. The method of claim 68, wherein The high frequency driver inputs two high frequency signals to the acousto-optic deflector, and the acousto-optic deflector outputs the laser beam to rotate between scanning angles determined according to the frequency of the high frequency signal input through the high frequency driver. Laser processing apparatus characterized in that. As an object processing method using a laser, Mounting the object on a stage; Setting control parameters according to the type and processing purpose of the object; Driving a beam scanner and driving a stage transport means to transport the stage at a predetermined speed; Emitting a laser beam; Dividing the emitted laser beam into at least two and irradiating the beam scanner with the beam scanner; And Irradiating the object with a laser beam reflected from the beam scanner; And the stage transfers in a direction opposite to the direction in which the laser beam is irradiated. The method of claim 70, And converting a cross section of the laser beam into an elliptic shape before irradiating the object with the laser beam reflected from the beam scanner. The method of claim 71 wherein And aligning the laser beam such that the long axis of the elliptic laser beam coincides with the processing direction of the object. The method of claim 70, The beam scanner is a polygon mirror, and seating a test object on the stage before seating the object on the stage; Driving the polygon mirror; After emitting a laser beam, dividing into two or more to enter the polygon mirror; And Calculating an error compensation value at each reflective surface of the polygon mirror according to a processing result of the test object; More, Adjusting the incidence angle of the laser beam according to the error compensation value after mounting the object on the stage and before irradiating the object with the laser beam reflected from the polygon mirror; Processing method. A method for laser processing an object formed of multiple layers, A first step of setting processing parameters according to each layer of the object formed of the multiple layers; A second step of irradiating the object with at least two divided laser beams according to the processing parameters set for the layer exposed to the processing area of the object to perform laser processing; A third step of confirming whether processing has been performed for all layers of the object formed of the multiple layers; And A fourth step of proceeding to the second step if the processing for all layers is not completed as a result of the checking of the third step; Laser processing method comprising a. The method of claim 74, wherein The second step may include a step 2-1 of driving a beam scanner; Step 2-2 of transferring the stage on which the object is seated; A second step of emitting a laser beam; 2-4, dividing the emitted laser beam into at least two; And (2-5) reflecting the at least two divided laser beams by the beam scanner to irradiate the processing region of the object; Laser processing method comprising a. 76. The method of claim 75 wherein The stage is laser processing method, characterized in that for feeding in the direction opposite to the laser beam irradiation direction. 76. The method of claim 75 wherein And converting a cross section of the laser beam into an elliptic shape before irradiating the object with the laser beam reflected by the beam scanner. 78. The method of claim 77 wherein And aligning the laser beam such that the long axis of the elliptic laser beam coincides with the processing direction of the object. The method of claim 74, wherein The processing parameters include laser output power, rotational speed of the beam scanner, stage feed rate at which the object is seated, irradiation frequency of the laser beam, focal position of the laser beam. A method for laser processing an object formed of multiple layers, Scribing both edge portions of the machining region with respect to the machining region of the object formed in the multi-layer; A second step of cutting the processing region by irradiating the object with at least two divided laser beams; Laser processing method comprising a. 81. The method of claim 80, The second step may include: setting a processing parameter according to each layer of the object formed of the multiple layers; Step 2-2 of performing laser processing according to the processing parameters set for the layer exposed to the processing region of the object; A third step of confirming whether or not machining of all layers of the object formed of the multi-layer is performed; And A step 2-4 of proceeding to the step 2-2 when the processing for all layers is not completed as a result of the checking of the step 2-3; Laser processing method comprising a. 82. The method of claim 81 wherein And said processing parameters include laser output power, stage feed rate at which an object is seated, irradiation frequency of the laser beam, and focal position of the laser beam. 82. The method of claim 81 wherein Step 2-2 is a laser processing method, characterized in that for performing the laser processing by converting the cross section of the laser beam into an elliptic shape. 84. The method of claim 83 wherein And aligning the laser beam such that the long axis of the elliptic laser beam coincides with the processing direction of the object. 81. The method of claim 80, And after the second step, a third step of healing the processing region. A method for laser processing an object formed of multiple layers, Irradiating at least two or more divided laser beams onto the object to cut a processing area of the object formed in the multiple layers; And A second step of healing the processing region of the cut object; Laser processing method comprising a. 87. The method of claim 86, The first step may include: setting a processing parameter according to each layer of the object formed of the multi-layer; A first to second step of performing laser processing according to the processing parameters set for the layer exposed to the processing region of the object; Steps 1-3 for confirming whether processing has been performed for all layers of the object formed of the multiple layers; And As a result of the check of the first step 1-3, if the processing for all the layers is not completed, the first step to proceed to the first step 1-2; Laser processing method comprising a. 88. The method of claim 87 wherein And said processing parameters include laser output power, stage feed rate at which an object is seated, irradiation frequency of the laser beam, and focal position of the laser beam. 88. The method of claim 87 wherein Said first step is a step of converting a cross section of said laser beam into an elliptic shape to perform laser processing. 92. The method of claim 89, And aligning the laser beam such that the long axis of the elliptic laser beam coincides with the processing direction of the object. As an object processing method using a laser, Mounting the object on a stage; Setting control parameters according to the type and processing purpose of the object; Adjusting the tilt and position of the first and second mirrors by the first and second actuators; Driving a reflection mirror; Transferring the stage at a preset speed; Emitting a laser beam from each of the plurality of laser generating means; Dividing the laser beams emitted from each of the plurality of laser generating means into at least two and then entering the first and second mirrors, respectively; And Irradiating a laser beam incident on the reflective mirror through the first and second mirrors to the object; Laser processing method comprising a. 92. The method of claim 91 wherein The stage is laser processing method, characterized in that for transferring in the direction opposite to the direction of the laser beam irradiated to the object. 92. The method of claim 91 wherein And converting a cross section of the laser beam into an elliptical shape before irradiating the laser beam incident on the reflective mirror to the object. 94. The method of claim 93, And aligning the laser beam such that the long axis of the elliptic laser beam coincides with the processing direction of the object.

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