KR20120071525A

KR20120071525A - Particle removing device for laser lift off machine

Info

Publication number: KR20120071525A
Application number: KR1020100133103A
Authority: KR
Inventors: 유병소; 장현삼
Original assignee: (주)큐엠씨
Priority date: 2010-12-23
Filing date: 2010-12-23
Publication date: 2012-07-03

Abstract

PURPOSE: A particle removing apparatus for laser lift off equipment is provided to effectively remove particles, produced during processing, through a process suction unit arranged around a processing area. CONSTITUTION: A particle removing apparatus for laser lift off equipment comprises a hydraulic unit(110) for supplying compressed air, a venturi pipe(120) which the compressed air supplied from the hydraulic unit passes through, a nozzle(122) which is arranged inside the venturi pipe to vary the inner cross section of the venturi pipe, a process suction unit(130) which is formed around a processing area irradiated with a laser beam, and a suction pipe which connects the process suction unit to the nozzle of the venturi pipe.

Description

Particle removal device of laser lift-off equipment {PARTICLE REMOVING DEVICE FOR LASER LIFT OFF MACHINE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser lift off machine, and more particularly, to a particle removal device for suctioning and removing particles generated during a laser processing process.

Recently, as the stability and power of an excimer laser beam are improved, the use range of the semiconductor material to the process of processing is expanding. In particular, in order to form a device such as a light emitting diode (LED), a process of separating a thin film on a substrate using a laser beam is performed. A typical equipment used in such a process is laser lift-off (Laser). Life Off: LLO)

The laser lift-off process may be divided into a scan irradiation method and a pulse irradiation method according to the irradiation method of the laser beam.

The scan irradiation method is a method of irradiating a laser by overlapping a plurality of laser beams at regular intervals. Such a scan irradiation method has an advantage that the productivity is excellent because the laser beam is irradiated on the front surface of the substrate. However, there is a problem that the lower layer may be thermally damaged and cracks or defects in the form of stripes occur in the overlapped portion.

In the pulse irradiation method, a laser beam processed to have the same shape and size as a cell is irradiated to each cell once. The laser irradiation method irradiates a laser beam having an energy greater than the binding energy between the thin film and the substrate. Separate them from each other. This method does not cause thermal damage to the lower layer, and the laser is irradiated once for each cell, so there is an advantage that defects due to overlap do not occur.

On the other hand, in the pulse irradiation method, since the laser beam is irradiated once for each cell, the separation of the thin film and the substrate largely depends on the energy size of the laser beam irradiated once.

An object of the present invention is to provide a particle removal device that can effectively remove particles generated during the wafer processing process of the laser lift-off equipment.

Another object of the present invention is to provide a particle removal device that is excellent in durability and easy to maintain by generating a vacuum using the Venturi principle.

It is still another object of the present invention to provide a particle removal device capable of removing particles in real time and removing particles remaining on a processed wafer while laser processing is performed.

The present invention is a pneumatic means for supplying compressed air; A venturi tube having a nozzle for passing the compressed air supplied from the pneumatic means and changing a cross sectional area therein; A process inlet formed around a processing region to which the laser beam is irradiated; And an air inlet pipe connecting the process inlet port and the nozzle of the venturi tube.

The venturi tube, the inlet connected to the pneumatic means has a wide cross-sectional area, it is preferable that the cross-sectional area is narrowed toward the area where the nozzle is formed.

In addition, the process inlet may be formed to surround the laser beam light source.

At this time, the process intake port is more preferably formed in a semicircular shape.

The apparatus may further include a filter unit provided at an outlet side of the venturi tube to adsorb particles discharged from the processing region.

The dust container may further include a dust container connected to an outlet side of the venturi tube and collecting particles transported in a mixed state with compressed air.

Here, the dust container preferably has a larger cross-sectional area than the venturi tube, and the dust container has an exhaust port formed at an upper portion thereof, and more preferably provided with a filter in the exhaust hole.

And, the present invention is a pneumatic means for supplying compressed air; A venturi tube having a nozzle for passing the compressed air supplied from the pneumatic means and changing a cross sectional area therein; A process inlet formed around a processing region to which the laser beam is irradiated; A post-process inlet disposed on the movement path of the work stage; An intake pipe connecting the process intake port and the post process intake port to nozzles of the venturi pipe, respectively; And a post process ejection port disposed around the post process inlet for receiving compressed air from the pneumatic means and spraying the compressed air toward the post process inlet.

The present invention provides a particle removal device that arranges a process inlet around a processing area and removes particles generated during a process online.

In addition, the present invention provides a particle removal device that does not cause a failure or damage of the equipment due to the particles by generating a suction force using the venturi tube.

In addition, the present invention provides a particle removal apparatus that can additionally remove particles remaining on the processed wafer surface.

1 to 4 are diagrams for explaining the vertical LED manufacturing processes,
5 is a block diagram showing a particle removal device of the laser lift-off equipment according to the first embodiment of the present invention,
6 is a perspective view showing a part of a process intake of a laser lift-off device having a particle removing device according to an embodiment of the present invention;
7 is a block diagram showing a particle removal device of the laser lift-off equipment according to a second embodiment of the present invention,
8 is a block diagram showing a particle removal device of the laser lift-off equipment according to a third embodiment of the present invention,
9 is a cross-sectional view showing a post-process inlet and a post-process inlet of the particle removing device according to the third embodiment of the present invention.

Hereinafter, a particle removal device of the laser lift-off device of the present invention will be described with reference to the accompanying drawings.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

In the drawings, it is to be noted that the sizes of the constituent elements of the invention are exaggerated for clarity of description, and when it is described that any constituent element is present inside or connected to another constituent element, The element may be installed in contact with the other element, may be installed at a predetermined distance from the element, and may be provided with a third element for fixing or connecting the element to the other element, The description of the means may be omitted.

1 to 4 are diagrams for explaining vertical LED manufacturing processes.

As shown in FIG. 1, the GaN buffer layer 31, the N-type GaN layer 32, and the InGaN / GaN / AlGaInN active layer 33 having multiple quantum wells on the sapphire substrate 20 by conventional semiconductor processing techniques. ), And a series of epi layers 30 including the P-type GaN layer 34 are sequentially formed.

Subsequently, as illustrated in FIG. 2, a plurality of trenches 30b penetrating the epi layer 30 are formed using a plasma reactive ion etching (RIE) method or the like.

Subsequently, as shown in FIG. 3, the conductive support layer 40 is formed on the GaN-based layers 30a. Subsequently, a laser lift-off process is performed to separate the sapphire substrate 20 from the GaN-based layers 30a.

The laser lift-off process is performed by irradiating a laser beam to the interface between the sapphire substrate 20 and the epi layer 30a through the sapphire substrate 20 in a single pulse manner. When performing the laser lift-off process, a shock wave with high pressure is generated at the interface between the sapphire substrate 20 to which the laser beam is irradiated and the epi layer 30a. Due to such a shock wave, a fracture or a crack may occur in the epi layer 30 corresponding to the edge portion of the laser beam spot to be irradiated. Thus, when the edge portion of the laser beam spot is precisely adjusted to be positioned in the trench 30b, damage to the epi layer 30a may be reduced by emitting shock waves generated in the laser lift-off process through the trench 30b.

In this manner, the sapphire substrate 20 can be separated from the epi layer 30a by sequentially irradiating the laser beam pulses to the entire area of the interface between the sapphire substrate 20 and the epi layer 30a.

Then, as shown in FIG. 4, a contact layer 50 is formed on each N-type GaN layer 32a. After the contact layer 50 is formed, it is separated into individual LED elements through a dicing process. The dicing process can be carried out through various mechanical or chemical methods.

5 is a block diagram showing a particle removal apparatus of the laser lift-off equipment according to the first embodiment of the present invention.

As shown, the particle removing device 100 according to the first embodiment of the present invention, the pneumatic means 110 for supplying the compressed air, and the compressed air supplied from the pneumatic means 110 passes through A venturi tube 120 having a nozzle 122 to change the cross-sectional area, a process inlet 130 formed around a processing region L to which a laser beam is irradiated, the process inlet 130 and the venturi tube ( And an intake pipe 132 connecting the nozzles 122 of the 120.

Venturi tube 120 is to use Bernoulli theorem.

Bernoulli's theorem is that the sum of the position head, pressure head and velocity head of the fluid is constant. The venturi tube 120 has a nozzle 122 therein. The nozzle 122 serves to reduce the cross-sectional area of the region through which the fluid passes.

When Bernoulli's theorem is applied to the venturi tube 120, the compressed air supplied from the pneumatic means 110 flows into the inlet 121 and passes through the region where the nozzle 122 is formed. Since the region in which the nozzle 122 is formed has a narrower cross-sectional area than the inlet 121 of the venturi tube 120, the speed of the compressed air in the nozzle 122 is increased, and thus the pressure is lowered.

When the pressure of the nozzle 122 is lowered in the venturi tube 120, negative pressure (suction input) is generated in the intake pipe 132 connected to the nozzle 122. Therefore, the air around the intake port 130 is sucked into the intake pipe 132 and discharged through the nozzle 122 to the outlet 125 of the venturi tube 120.

The particle removing device 100 according to the first embodiment is for removing particles such as scattering particles, dust, etc. generated during laser processing. The particle removing apparatus 100 is disposed at the time of laser processing by arranging the process inlet 130 around the processing area L. It sucks and removes the particles generated in the on-line (on-line) in real time.

Particle removal apparatus 100 according to the invention is characterized in that for generating a suction force for sucking the particles using the venturi tube (120). Conventional particle removal apparatuses have used a method of sucking particles generated during laser processing by using a vacuum pump, but a method using a vacuum pump inevitably sucks the sucked particles into the vacuum pump. Particles are sucked into and deposited inside the vacuum pump, so the suction power of the vacuum pump is lowered and causes a failure. Therefore, the vacuum pump has to be checked regularly.

On the other hand, the particle removal device 100 according to the present invention does not generate a suction force by using a suction device such as a vacuum pump, but generates a suction force by supplying compressed air to the venturi tube, the particles are introduced into the pneumatic means. The problem does not occur.

The particle removing device 100 according to the present invention supplies the compressed air to the venturi tube 120 from the pneumatic means 110 composed of a compressor or a compressed air tank. The compressed air introduced into the venturi tube 120 is lowered while passing through the nozzle 122, and at this time, a suction force is generated at the inlet 130 connected to the nozzle 12. In addition, the particles sucked in the mixed state with the air through the inlet port 130 passes through the nozzle 122 and is discharged to the outlet 125. Therefore, even if the particle removal device is continuously used, the sucked particles do not affect the pneumatic device. The outlet 125 of the venturi tube 120 may include a filter or a dust container for collecting the discharged particles. Can be. A filter or dust box prevents particles from scattering elsewhere.

FIG. 6 is a perspective view illustrating a process intake port of a laser lift-off device including a particle removing device according to an exemplary embodiment of the present invention. FIG.

As shown, the laser lift-off equipment includes a laser beam irradiator 300 for irradiating laser light and an image acquisition device 400 disposed around the laser beam irradiator 300.

The image acquisition apparatus 400 includes an inspection camera 410 for identifying and inspecting the position of the wafer chip, and a process camera 420 for acquiring a moving image.

In addition, a process inlet 130 is disposed around the processing region L positioned below the laser beam irradiation apparatus 300. In this case, the process camera 420 is required to acquire a moving image of the processing area L, and must secure a photographing area of the process camera 420. Therefore, the process intake port 130 should not be formed between the process camera 420 and the processing area L, and is preferably formed in a semicircle around the area where laser processing is performed.

7 is a block diagram illustrating an apparatus for removing particles of a laser lift-off device according to a second embodiment of the present invention.

The second embodiment is characterized in that the dust container 150 is disposed at the outlet 125 of the venturi tube 120.

Dust bin 150 is to remove the particles from the air mixed with particles, and to allow the clean air to be discharged to the outside. As described above, the outlet air 125 of the venturi tube 120 discharges the compressed air supplied from the pneumatic means 110 and the air mixed in the mixed state with the particles through the inlet 130. Particles that are discharged together do not affect the pneumatic means 110 but may scatter into the air and contaminate other parts of the equipment.

In order to prevent this, by placing the dust container 150 at the outlet 125 of the venturi tube 120, it is to be able to filter the particles in the dust container 150.

Particles are conveyed by the pressure of the compressed air to be transported, and when the flow rate is lowered in the dust container 150, the particles sink down by their own weight.

Dust bin 150 has a larger cross-sectional area than the venturi tube 120, if the air discharged from the outlet of the venturi tube 120 reaches the dust container 150, the movement speed of the air is reduced due to the increase in the cross-sectional area do. As the air velocity decreases, the larger particles sink, and the smaller particles float.

As illustrated in the dust container 150, an exhaust port 152 is disposed at an upper portion thereof, and the exhaust port 152 is provided with a filter 154. In spite of the decrease in air velocity, particles that have been transported with the air are caught by the filter 154. Therefore, the air discharged to the exhaust port 152 of the dust container 150 is to maintain a clean state containing no particles.

8 is a block diagram illustrating a particle removal apparatus of the laser lift-off equipment according to a third embodiment of the present invention, and FIG. 9 is a post-process jet port and a post-process inlet of the particle removal device according to a third embodiment of the present invention. It is a cross-sectional block diagram shown.

Particle removal apparatus 200 according to the third embodiment of the present invention, the pneumatic means 210 for supplying the compressed air, the compressed air supplied from the pneumatic means 210 passes through the nozzle so that the cross-sectional area therein is changed; A venturi tube 220 having a 222, a process inlet port 230 formed around a processing area to which a laser beam is irradiated, a post process inlet port 240 arranged on a movement path of a work stage, and the process An air inlet 232 for connecting the inlet port 230 and the post process inlet port 240 to the nozzle 222 of the venturi tube 220, and a pneumatic means disposed around the post process inlet port 230. It receives the compressed air from the 210 and the post-process jet port 250 for injecting the compressed air toward the post-process inlet 230.

The third embodiment includes a post process inlet 240 and a post process outlet 250 in addition to the process inlet 230.

The post process air inlet 240 and the post process air outlet 250 are disposed to be adjacent to each other, and the compressed air injected from the post process air outlet 240 may be sucked into the post process air inlet 240 through the surface of the wafer. It is preferable.

If the air is simply intake, all of the surrounding air flows into the intake port, which may cause a large loss. In the embodiment, the post-process jet 240 is provided to allow the air injected from the post-process jet 240 to sweep the wafer surface, thereby improving the particle removal effect.

The post-process inlet 240 and the post-process outlet 250 are disposed in a path through which the wafer having completed the wafer processing is transferred.

In an embodiment, the process inlet 230 may collect particles generated in the process, and the post process inlet 240 and the post process outlet 250 may remove particles remaining on the wafer surface on which the process is completed.

Referring to FIG. 9, when compressed air is injected obliquely toward the surface of the wafer W from the post process jet 250, the injected compressed air moves by sweeping down the surface of the wafer W, and then is disposed in close proximity to the post process. It is configured to flow into the inlet port 240.

Therefore, the particles remaining on the wafer surface are introduced into the post process inlet 240 and discharged to the outlet 225 of the venturi tube 220.

As in the first embodiment, a separate filter unit may be provided at the outlet of the venturi tube 220, and the dust container shown in the second embodiment may be provided.

In the exemplary embodiment shown in FIG. 8, although the process inlet port 230 and the post process inlet port 240 are both connected to one venturi tube 220, the venturi tube 220 includes two venturi tubes 220. Two venturi tubes 220 may be connected to the process inlet 230 and the post process inlet 240, respectively.

In addition, one inlet 230 may be connected to the plurality of venturi tubes 220 in order to provide a greater suction force.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments but may be manufactured in various forms, and having ordinary skill in the art to which the present invention pertains. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

100, 200: particle removal device
110, 210: pneumatic means
120, 220: Venturi tube
130, 230: process inlet
150: dust bucket
300: laser beam irradiation device
400: image acquisition device

Claims

Pneumatic means for supplying compressed air;
A venturi tube having a nozzle for passing the compressed air supplied from the pneumatic means and changing a cross sectional area therein;
A process inlet formed around a processing region to which the laser beam is irradiated; And
And an intake pipe connecting the process intake port and the nozzle of the venturi tube.

The method of claim 1,
The venturi tube,
Inlet connected to the pneumatic means has a wide cross-sectional area, the particle removal device of the laser lift-off equipment, characterized in that the cross-sectional area is narrowed toward the area where the nozzle is formed.

The method of claim 1,
The particle inlet of the laser lift-off equipment, characterized in that the process inlet is formed in a shape surrounding the periphery of the laser beam light source.

The method of claim 3, wherein
And said process inlet is formed in a semi-circular shape.

The method of claim 1,
Particle removal apparatus of the laser lift-off equipment further comprises a filter unit provided on the outlet side of the venturi tube adsorbing particles discharged from the processing area.

The method of claim 1,
Particle removal apparatus of the laser lift-off equipment further comprises a dust container connected to the outlet side of the venturi tube and collects the particles conveyed in a mixed state with the compressed air.

The method according to claim 6,
The dust container has a larger cross-sectional area than the venturi tube, the particle removal device of the laser lift-off equipment.

The method of claim 7, wherein
The dust container has an exhaust port formed at the upper portion, the particle removal device of the laser lift-off equipment, characterized in that provided with a filter in the exhaust port.

Pneumatic means for supplying compressed air;
A venturi tube having a nozzle for passing the compressed air supplied from the pneumatic means and changing a cross sectional area therein;
A process inlet formed around a processing region to which the laser beam is irradiated;
A post-process inlet disposed on the movement path of the work stage;
An intake pipe connecting the process intake port and the post process intake port to nozzles of the venturi pipe, respectively; And
And a post process blowout outlet disposed around the post process inlet for receiving compressed air from the pneumatic means and spraying the compressed air toward the post process inlet.

The method of claim 9,
The particle inlet of the laser lift-off equipment, characterized in that the process inlet is formed in a shape surrounding the periphery of the laser beam light source.

11. The method of claim 10,
And said process inlet is formed in a semi-circular shape.

11. The method of claim 10,
Particle removal apparatus of the laser lift off equipment further comprises a filter unit for adsorbing the particles are discharged provided on the outlet side of the venturi tube.

The method of claim 9,
Particle removal apparatus of the laser lift-off equipment further comprises a dust container connected to the outlet side of the venturi tube and collects the particles conveyed in a mixed state with the compressed air.

The method of claim 13,
The dust container has a larger cross-sectional area than the venturi tube, the particle removal device of the laser lift-off equipment.

15. The method of claim 14,
The dust container has an exhaust port formed at the upper portion, the particle removal device of the laser lift-off equipment, characterized in that provided with a filter in the exhaust port.