WO2007013293A1

WO2007013293A1 - Hybrid laser processing system

Info

Publication number: WO2007013293A1
Application number: PCT/JP2006/313751
Authority: WO
Inventors: Yoshihiro Kawahara; Motoi Sasaki; Ryoji Koseki
Original assignee: Shibuya Kogyo Co., Ltd.
Priority date: 2005-07-26
Filing date: 2006-07-11
Publication date: 2007-02-01
Also published as: JP2007029980A

Abstract

A hybrid laser processing system (1) comprises a laser oscillator (4) for oscillating laser light (L) to a processing head (6), and a liquid supplying means (5) for supplying a high pressure liquid to the processing head. In the hybrid laser processing system, a liquid column (W) is ejected from an ejection hole (48) provided at the distal end of the processing head and a workpiece (2) is cut by guiding laser light to the liquid column. The liquid column collides against the workpiece and bounces toward the processing head but since the liquid is blocked by a partition member (44), an air flow flowing toward the liquid column (W) in a gas passage between the processing head and the partition member is not disturbed and the liquid column can reach the workpiece without being diffused since an air flow is flowing along the liquid column. A long stabilized liquid column can be formed even if the ejection hole and the workpiece are located closely to each other.

Description

Specification

Hybrid laser processing equipment

Technical field

TECHNICAL FIELD [0001] The present invention relates to a hybrid laser cafe apparatus, and more particularly to a hybrid laser processing apparatus that ejects liquid from an ejection hole into a liquid column and ejects the liquid to the outside and guides laser light to the liquid column.

Background art

Conventionally, a processing head having an injection hole, a liquid supply unit that supplies a high-pressure liquid to the processing head, and a laser oscillator that oscillates laser light, the liquid supplied from the liquid supply unit is provided. There is known a hybrid laser processing apparatus for processing a workpiece by making a liquid column from an injection hole to be ejected to the outside and guiding a laser beam to the liquid column. (Patent Document 1)

In such a hybrid laser cage apparatus, it is necessary to reach the work piece in a stable state without diffusing the injected liquid column, and the interval between the injection hole and the work piece is set to be injected. The liquid column must be determined within a certain range.

Patent Document 1: Japanese Patent Publication No. 10-500903

Disclosure of the invention

Problems to be solved by the invention

[0003] Here, in order to stably form the liquid column, an air flow directed toward the workpiece along the liquid column is required, and this air flow is generated by jetting the liquid column. When the gas around this is moved along the liquid column and this air flow is generated, the surrounding gas is pulled toward the liquid column, and an air current directed toward the liquid column is generated. .

In addition, when cutting a semiconductor wafer or the like using a hybrid laser processing apparatus, it is required to reduce the diameter of the liquid column to be sprayed to reduce the cutting width. There is a correlation between the length that can be maintained in a stable state, and therefore, in order to reduce the diameter of the liquid column, the injection hole and the workpiece must be brought close to each other.

However, if the injection hole and the object to be moved are brought too close to each other, the collision with the object to be covered will occur. The splashed liquid column bounces, the bounced liquid reaches the periphery of the injection hole, and the airflow in the vicinity of the injection hole flowing toward the liquid column is disturbed. As a result, the airflow flowing along the liquid column is also disturbed. Therefore, a stable liquid column cannot be obtained.

In view of such a problem, the present invention provides a laser beam processing apparatus capable of forming a stable liquid column long even when an injection hole and a workpiece are close to each other. Means for solving the problem

[0004] That is, the hybrid laser carriage device according to the present invention oscillates laser light, a processing head having an injection hole, a liquid supply means for supplying high-pressure liquid to the processing head, and the like. A laser oscillator, and the liquid supplied from the liquid supply means is ejected to the outside as a liquid column from the ejection hole, and the laser beam is guided to the liquid column to process the object to be coated. In the hybrid laser carriage system,

A partition member with a passage hole through which the liquid column passes is provided between the processing head and the workpiece, and the partition member prevents the liquid bounced off the workpiece from reaching the processing head. In addition, a gas passage is formed between the processing head and the partition member.

The invention's effect

[0005] According to the present invention, by providing the partition member, the liquid that has bounced off the workpiece does not reach the periphery of the spray hole, and the inside of the gas passage formed between the heating head and the partition member Since the airflow flowing through the pipe is not disturbed, a stable liquid column can be formed long even if the injection hole and the workpiece are brought close to each other.

BEST MODE FOR CARRYING OUT THE INVENTION

[0006] The illustrated embodiment will be described below. FIG. 1 shows a hybrid laser processing apparatus 1 that works according to the present invention, and guides a laser beam L to a liquid column W formed by jetting a liquid, thereby processing the workpiece. This is a device that cuts object 2 into the required shape.

The hybrid laser carriage apparatus 1 includes a processing table 3 that supports the above-described object 2, a laser oscillator 4 that oscillates laser light L, and a liquid supply means that supplies liquid such as high-pressure water. 5 and a processing head 6 for injecting the liquid as a liquid column W toward the object 2 and guiding the laser beam L to the liquid column W. These are controlled by control means (not shown). To be controlled.

The machining table 3 is conventionally known and will not be described in detail. However, the workpiece 2 is moved in the horizontal direction with respect to the machining head 6, and the machining head 6 is Not shown, moved vertically by lifting and lowering means!

In the present embodiment, a thin semiconductor wafer is cut as the above-described object 2 and, in addition, a composite material such as an epoxy resin board and a resin can be cut. it can. In addition to cutting and drilling force, grooving can also be performed on the surface of the workpiece 2.

[0007] The laser oscillator 4 is a YAG laser oscillator, which can perform CW oscillation or pulse oscillation according to processing, and can adjust processing conditions such as its output and pulse oscillation period as appropriate. .

Between the laser oscillator 4 and the processing head 6, a shotter means 11 for blocking the laser light L, a reflection mirror 12 for reflecting the laser light L toward the processing head 6, and the irradiated laser light L are collected. And a condensing lens 13 is provided.

The shatter means 11 is controlled by the control means, and a reflection mirror 11a that reciprocates on and off the optical path of the laser light L by driving means (not shown), and the energy of the laser light L reflected by the reflection mirror 11a. It is equipped with 1 lb of damper that absorbs. When the reflection mirror 11a is positioned on the optical path of the laser light L, the laser light L is reflected by the reflection mirror 11a, and the energy of the laser light is absorbed by the damper ib. On the other hand, when the reflecting mirror 11a is moved out of the optical path of the laser beam L, the laser beam L is reflected by the reflecting mirror 12 and then irradiated to the processing head 6 through the condenser lens 13. Other laser oscillators such as semiconductor lasers and CO laser oscillators are used.

2

Although it is possible, the laser light L oscillated like a CO laser oscillator is absorbed by water.

2

In the case of a wavelength, the liquid ejected from the heating head 6 may be a liquid that is difficult for laser light to absorb.

[0008] Next, the liquid supply means 5 includes a water storage tank 21 for storing water, and a pump 22 for feeding the water stored in the water storage tank 21 toward the carriage head 6, which includes a conduit 23 Are connected to each other. The water storage tank 21 is connected to a water supply source 24. A conduit 23 connecting the water supply source 24 and the water storage tank 21 has an on-off valve 25 for controlling the supply of water from the water supply source 24, and a water supply source 24. And a spillage filter 26 for removing foreign substances contained in the water supplied from the water.

Between the pump 22 and the processing head 6, in order from the upstream pump 22 side, a check valve 27 for preventing the backflow of water to the pump 22, and the pulsation of the water to be fed are prevented, and the processing head An accumulator 28 for supplying high-pressure water, a filter 29 for removing foreign substances in the water, and a first electromagnetic valve 30 whose opening / closing is controlled by the control means are provided in 6.

In addition, the conduit 23 from the water supply source 24 to the water storage tank 21 and the conduit 23 from the pump 22 to the processing head 6 are connected by two parallel conduits 23, and one conduit 23 is connected to the second electromagnetic The valve 31 is provided, and the other conduit 23 is provided with a pressure regulating valve 32.

The second solenoid valve 31 is used to return the liquid from the pump 22 to the water storage tank 21 when stopping the hybrid laser carriage device 1, and the pressure regulating valve 32 is used from the pump 22 to the carriage head. Up to 6 is provided to keep the pressure inside the conduit 23 constant. FIG. 2 shows an enlarged view of the machining head 6. The machining head 6 includes a housing 41 that is moved by the moving means, an injection nozzle 42 that is provided below the housing 41, and an injection nozzle 42. And a transparent glass plate 43 provided between the condenser lens 13 and a partition member 44 provided below the injection nozzle 42.

A side surface of the housing 41 is provided with a connection port 41a that communicates with a liquid passage 45 formed between the glass plate 43 and the injection nozzle 42 and is connected to the conduit 23. The liquid supplied from the means 5 flows into the liquid passage 45 from the connection port 41a and is then ejected as the liquid column W from the ejection nozzle 42.

The injection nozzle 42 is fixed to the center of a stay 46 fitted to the lower end portion of the housing 41, and the stay 46 is fixed to the lower surface of the housing 41 with a ring-shaped fixing member 47.

An injection hole 48 is formed in the center of the injection nozzle 42. The injection hole 48 is formed on the condensing lens 13 side and has a first inclined surface 48a having a diameter reduced toward the workpiece 2, and the first It is composed of a second inclined surface 48c whose diameter is expanded from the minimum diameter portion 48b of the inclined surface 48a toward the workpiece 2 side. Under the injection nozzle 42, through holes 46a and 47a that penetrate the stay 46 and the fixing member 47 are formed. The diameters of the through holes 46a and 47a are smaller than the outer diameter of the injection nozzle 42. In addition, the diameter is set larger than the diameter of the lower end portion of the second inclined surface 48c. The glass plate 43 is located between the spray nozzle 42 and the condenser lens 13 and is fixed to the housing 41 with a nut 49, so that the liquid in the liquid passage 45 is more liquid than the glass plate 43. The leakage of light into the upper space is prevented, and the laser light L collected by the condenser lens 13 is transmitted.

[0010] The partition member 44 is a circular plate-like member having a passage hole 44a formed in the center. The partition member 44 is formed on the lower surface of the fixing member 47 with bolts 51 via four cylindrical spacers 50. It is fixed.

The partition member 44 forms a gas passage 52 between the partition member 44 and the fixing member 47, and the gas passage 52 communicates with the atmosphere through the space between the adjacent spacers 50. It is like that.

The passage hole 44a has a chamfered shape that expands downward, and the diameter of the passage hole 44a on the side of the injection nozzle 42 is directed toward the object 2 along the liquid column W. It is set so that it does not block the airflow that circulates! In the present embodiment, when the diameter of the liquid column to be ejected is 50 / z m, the diameter of the passage hole 44a is set to 0.5 mm to 5 mm.

In addition, by adopting a chamfered shape in which the diameter of the passage hole 44a is expanded downward, the liquid adhering to the partition member 44 is gradually separated from the liquid column W when moving downward along the passage hole 44a. Do not touch the liquid column W!

The operation of the hybrid laser carriage apparatus 1 having such a configuration will be described.

First, when the hybrid laser processing apparatus 1 is started, the control means controls the liquid supply means 5 and starts feeding the water in the water storage tank 21 toward the carriage head 6 by the pump 22. A sufficient amount of water is supplied to the water storage tank 21 from a water supply source 24 in advance.

Then, the water fed by the pump 22 passes through the check valve 27 and then flows into the accumulator 28. When the accumulator 28 is filled with water, the filter 29 and It passes through the first solenoid valve 30 and flows into the liquid passage 45 via the connection port 41a of the above-described cache head 6.

Thereafter, when the liquid passage 45 is filled with water, the water is injected from the injection hole 48 of the injection nozzle 42, and the injected water reaches the workpiece 2 as a liquid column W.

In parallel with this, the control means controls the laser oscillator 4 and the laser oscillator 4 starts oscillation of the laser light L. At this time, the reflection mirror 11a of the shirter means 11 is positioned on the optical path of the oscillated laser beam L, and the laser beam L is guided to the damper l ib by the reflection mirror 11a, and the energy of the laser beam L is Absorbed.

When the liquid column W ejected from the ejection hole 48 becomes stable, the control means immediately controls the shutter means 11 to move the reflecting mirror 11a out of the optical path of the laser light L, thereby causing the laser light L Is reflected by the reflecting mirror 12 and then condensed by the condenser lens 13.

The condensed laser beam L passes through the liquid in the glass plate 43 and the liquid passage 45, is further reflected by the first inclined surface 48a of the injection hole 48, and is guided into the liquid column W, and then in the liquid column W. The target object 2 is irradiated while repeating reflection.

Here, a space is formed around the liquid column W ejected from the ejection hole 48 between the stay 46 and the inner wall surface of the through holes 46a and 47a formed in the fixing member 47. This space functions as a so-called air pocket P.

That is, when the liquid column W is ejected from the ejection hole 48, an airflow is generated around the liquid column W to the workpiece 2 along the liquid column W, and accordingly, below the fixing member 47. The air stream flowing toward the liquid column W is generated.

When a part of the airflow generated below the fixing member 47 flows into the air pocket P as indicated by the arrow A, it is reversed at the upper end of the air pocket P, and then processed along the liquid column W. It flows to the object 2 side.

The liquid column W injected from the injection hole 48 is not diffused for a while and remains stable for a while due to the airflow flowing toward the target object 2 along the liquid column W, while the laser beam L Reflects well in the liquid column W.

Here, when the thickness of the liquid column W and the distance (stable length) until the liquid column W injected from the injection hole 48 diffuses were actually measured, the pressure of the injected liquid column W was 13 MPa. When Liquid column diameter = 100 μm, stable length = about 90 mm, liquid column diameter = 70 μm, stable length = about 60 mm, liquid column diameter = 50 m, stable length = about 40 mm. This stable length can be increased by increasing the pressure of the liquid column W.

[0013] The liquid column W ejected from the ejection hole 48 in this way is a force that reaches the workpiece 2. At this time, when the workpiece 2 is subjected to grooving, the liquid column W is processed. If the object 2 does not penetrate, the liquid column W will collide with the object 2 and the scattered liquid will bounce upward.

Therefore, the liquid that bounces up to the bottom reaches the lower surface of the fixing member. However, in this embodiment, the bounced liquid is blocked by the partition member 44, and therefore reaches the lower surface of the fixing member 47. Flower ,.

In this way, by preventing the liquid bounced off by the partition member 44 from reaching the fixing member 47, the airflow flowing toward the liquid column W can be prevented from being disturbed by the liquid. Thus, the airflow flowing along the liquid column W is disturbed and the liquid column W can be prevented from diffusing.

On the other hand, when the liquid column W is ejected without providing the partition member 44 as in Patent Document 1, the liquid bounced off the workpiece 2 reaches the lower surface of the fixing member 47 and is directed toward the liquid column W by this liquid. Therefore, the airflow flowing along the liquid column W is disturbed, and the airflow flowing along the liquid column W is also disturbed, so that the stable liquid column W cannot be ejected.

For this reason, in the conventional hybrid laser processing apparatus 1, the distance between the processing head 6 and the workpiece 2 is made longer than the height at which the rebounding liquid reaches, and the liquid column W is thickened by that amount. The distance that W reaches stably has to be increased, and the cutting width becomes wider, which has been a factor in reducing the yield of semiconductor wafers.

In addition, since the gas passage 52 formed between the partition member 44 and the fixing member 47 communicates with the atmosphere between the adjacent spacers 50, the air flow in the gas passage 52 is also reduced. If the gas flow is disturbed and the liquid column W diffuses due to insufficient gas flow, V will not cause the same problem.

Next, a second embodiment of the present invention shown in FIG. 3 will be described. In the second embodiment, only the configuration of the partition member 44 is different, so the description of the same members and the like as in the first embodiment will be omitted. The partition member 44 of the present embodiment is a bottomed cylindrical member, and is fixed so as to cover the lower surface of the processing head 6. The partition member 44 has a lower surface center in the same manner as in the first embodiment. The passage hole 44a is formed.

In addition, a plurality of communication ports 44b are formed in the side surface of the partition member 44 so that the gas passage 52 formed in the partition member 44 communicates with the atmosphere.

With such a configuration, when the liquid column W is ejected from the ejection hole 48, the gas in the gas passage 52 becomes an air flow that flows along the liquid column W to the target object 2, and at this time, the communication port Since the atmosphere flows into the gas passage 52 from 44b, the air flow is disturbed and the liquid column W is diffused due to insufficient gas flow rate.

Even if the liquid column W that has passed through the passage hole 44a collides with the target object 2, the bounced liquid hits the lower surface of the partition member 44. Therefore, the air flow in the gas passage 52 is not disturbed, and the first Similar to the embodiment, the workpiece 2 can be machined while the machining head 6 and the workpiece 2 are brought close to each other.

Brief Description of Drawings

FIG. 1 is a layout view of a hybrid laser carriage device in the present embodiment.

[Fig. 2] An enlarged cross-sectional view of the machining head.

FIG. 3 is an enlarged cross-sectional view of a machining head in a second embodiment.

Explanation of symbols

1 Hybrid laser processing equipment 2 Workpiece

4 Laser oscillator 5 High pressure pump

6 Processing head 42 Injection nozzle

44 Partition member 44a Passing hole

48 Injection hole 52 Gas passage

L Laser beam P Air pocket

W liquid column

Claims

The scope of the claims

[1] A processing head having an injection hole, a liquid supply unit that supplies a high-pressure liquid to the processing head, and a laser oscillator that oscillates laser light, and the liquid supplied from the liquid supply unit In a hybrid laser processing apparatus for processing a workpiece by guiding a laser beam to the liquid column and injecting the laser beam to the outside,

A partition member with a passage hole through which the liquid column passes is provided between the processing head and the workpiece, and the partition member prevents the liquid bounced off the workpiece from reaching the processing head. And a gas path is formed between the processing head and the partition member.

[2] The hybrid laser according to claim 1, wherein the partition member is a bottomed cylindrical member that covers the tip of the processing head, and a communication port that communicates with the atmosphere is formed on a side surface of the partition member. Processing equipment.

[3] A wall surface surrounding the liquid column is formed at the lower end of the processing head on the workpiece side with respect to the injection hole, and a space formed by the liquid column and the wall surface is used as an air pocket. The hybrid laser processing apparatus according to claim 1 or 2, wherein