JP2007029973A - Apparatus and method for laser beam machining, and apparatus and method for collecting debris - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for laser beam machining, which apparatus can prevent the re-sticking of debris on the surface of a workpiece, the debris being produced during abrasion machining carried out by radiating a laser beam, and further to provide a method for laser beam machining, and further to provide an apparatus and a method for collecting the debris. <P>SOLUTION: In the apparatus and the method for laser beam machining for carrying out the patterning for a transparent resin layer, a resin film, and a metal thin film formed on a substrate, and the apparatus and the method for collecting the debris, liquid 3 is circulated in the aperture portions of a laser radiating means and the final end lens 21 among an optical projecting lens group 18, 19, 20, 21 of a debris collecting portion 4 which are arranged above the substrate 2, and a liquid immersed portion 24 is locally formed between the machining surfaces of the transparent resin layer, the resin film, and the metal thin film 22, when the transparent resin layer 22 is formed on the substrate 2. As a result, minute particles, such as debris, dross, mist, and fumes produced during the patterning by the irradiation by the laser beam 17 are discharged into the liquid immersed portion 24 and are collected by circulating the liquid. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laser processing apparatus and a laser processing method for patterning a transparent conductive film, a resin film, and a metal thin film used for transparent electrodes on multilayer thin films such as FPD (flat panel display) and solar cells, Irradiation of laser light from the top surface of the object to be processed, and processing scattered matter (debris: minute particles such as debris, dross, mist, and fume) generated during laser processing by photochemical reaction (ablation), thermal melting, or their combined action The present invention relates to a laser processing device, a processing method, a debris recovery device, and a recovery method for effectively removing and recovering the substrate by immersing and circulating locally with a liquid.

In the world of fine processes that handle FPDs such as liquid crystal panels, transparent conductive films, resin films, and metal thin films are usually patterned into a desired shape by photolithography. For example, glass, plastic, on a substrate such as a silicon wafer, ITO (I ndium T in O xides) film, or ZnO transparent conductive film made of zinc oxide () film or the like by vacuum deposition, forming a resist layer thereon Then, the resist layer is exposed by irradiating light through a photomask having a predetermined pattern. Then, the photomask pattern is transferred to the resist layer by development and post-baking, the portion of the transparent conductive film that is not covered with the resist is removed by wet etching, and finally the residual resist layer is removed to remove the desired resist layer. A transparent conductive film pattern is obtained.

  In the current FPD- and LCD (liquid crystal display device), the substrate size is increased to improve the yield, and in the 8th generation display, 2 meters □ are planned. It is becoming inevitable. In the next generation display, the design pattern rule is going to cut below 2 microns, and the circuit pattern has been miniaturized, and pattern formation technology using photolithography has become indispensable for the production of these. Yes. However, when photolithography technology is used, a large device such as a coater / developer is required as represented by exposure / development / etching, and a large amount of chemical solution such as developer is used. Equipment costs, material costs, and the like are spent, and this is also a problem in terms of capital investment, footprint, and environmental conservation. Therefore, Patent Document 1 discloses a technique of directly processing a transparent conductive film using laser light in order to omit the photolithography process and simplify the manufacturing process.

  As described above, when an excimer laser is used as a laser processing apparatus and processing method using laser light without using a photolithography method, the excimer laser has high photon energy capable of breaking chemical bonds, and ablation ( A chemical reaction called Abrasion) can remove the workpiece while suppressing the thermal effect. Laser processing by such ablation. By irradiating the excimer laser light with adjusted energy density, various materials such as plastic, metal, ceramics, and the like can be ablated. In this processing, products formed by absorbing and reacting with laser light from the surface to be processed that has been irradiated with laser, and scattered objects called debris, which are minute particles of the material to be processed, move in the air. Diffuses and reattaches to the substrate. Especially when reaction products adhere to the substrate, they are deprived of heat and solidify, and they cannot be removed even by physical cleaning with a brush or the like. Particles (dust) at a level that is 100% defective. Therefore, in the method of directly patterning with an optical laser, a technique for suppressing minute particles such as debris, dross, mist, and fume is an essential matter.

  As described above, as a debris suppression method, there are known a method for suppressing the generation of minute particles such as debris, dross, mist and fume, a method for reducing debris accumulation, and a method for collecting debris after debris deposition. ing. In order to reduce the amount of debris generated, it is known that it is effective to spray an assist gas together with the irradiation of the laser beam onto the workpiece. In addition, as a method of suppressing the occurrence of debris itself, a method of preventing decomposition or reattachment with a predetermined atmospheric gas is known. Further, the laser irradiation area is physically covered and collected by flowing air. The method is also disclosed in Patent Document 2. Furthermore, as a method of reducing the accumulation of debris on the substrate, a fluid delivery device for ejecting gas is provided on the surface in the vicinity of the processing region, and a suction duct for sucking fluid is installed on the opposite side, and processing scattered matter and Japanese Patent Application Laid-Open No. H10-228561 discloses a method of blowing off debris from the processing region and simultaneously sucking and removing the debris.

  However, the purpose of collecting fine particles such as debris, dross, mist, and fume is to collect debris to the extent that it does not affect the human body. Fine devices such as transparent conductive films formed on liquid crystal panel glass substrates However, the effect is low and problematic in the next-generation device that requires fine processing.

  Furthermore, as a laser processing method that prevents adhesion of debris generated during laser processing as a debris adhesion prevention method and can obtain a good processed surface, a liquid such as water is applied to the surface of the workpiece to be ablated. The surface of the object to be processed is irradiated with YAG or YLF laser light through this liquid, and the generated debris is suspended in the liquid. After the processing is completed, the debris is washed away together with the liquid, and the surface of the object to be processed is debris. Patent Document 4 discloses a technique for preventing the adhesion.

  However, in the above method, there is a possibility that debris floating in the liquid in contact with the surface of the workpiece will reattach to the surface of the workpiece, and it is possible to completely prevent the debris from adhering to the surface of the workpiece. I could not do it. Therefore, Patent Document 5 proposes a laser processing apparatus and a laser processing method that solve these problems and are the basis of the present invention. In Patent Document 5, a laser light source and a laser beam emitted from the laser light source are used for the object to be processed in order to prevent processing scattered matter generated when ablation processing is performed by laser light irradiation from adhering to the surface of the object to be processed. An optical system that optically projects a predetermined pattern on a processing surface of an object and processes the processing surface by ablation, and is a liquid that transmits laser light to the processing surface irradiated with laser light A laser processing method and a laser processing apparatus provided with a liquid supply mechanism for supplying a liquid and moving a liquid in a predetermined direction on a processing surface are disclosed.

  The configuration disclosed in Patent Document 5 will be described with reference to FIG. FIG. 6 is a cross-sectional view showing the structure of the debris adhesion prevention mechanism of the laser processing apparatus. The adhesion prevention mechanism 50 emits the laser beam LB during the irradiation of the laser beam LB onto the workpiece surface 51F of the workpiece 51. By supplying the permeating liquid to the processing surface 51F and moving the liquid in a predetermined direction on the processing surface 5F, the debris generated by the ablation processing is washed away. 53 and a liquid supply source 54. The holding mechanism 53 is installed on the stage 55 and holds the workpiece 51. The holding mechanism 53 includes a processing container 56 and a cover member 57.

  The processing container 56 is installed on a stage 55. The processing container 56 is opened at the upper end side, and the workpiece 51 is installed at the bottom. The cover member 57 is installed on the inner periphery of the processing container 56 on the opening side, and is fixed to the processing container 56 by a fixing member 58 fixed to the opening end of the processing container 56. An opening 59 for introducing the laser beam LB into the processing container 56 is formed in the fixing member 58. The cover member 57 is made of a material that transmits the laser beam LB incident from the opening side of the processing container 56. For example, when a KrF excimer laser having a wavelength of 248 nm is used as a laser light source, the cover member 57 has a transmittance with respect to the KrF excimer laser. The one made of high synthetic quartz glass or calcium fluoride is used. Further, the cover member 57 is disposed at a predetermined height, for example, about 1 mm from the processing surface 51F of the processing target object 51 installed at the bottom of the processing container 56. That is, a predetermined gap Gp is formed between the processed surface 51F of the workpiece 51 and the cover member 57. The liquid 60 passes through this gap Gp. By installing the cover member 57 on the inner periphery of the processing container 56, a closed space Sp is formed between the cover member 57 and the processing container 56. The liquid 60 is supplied to the closed space Sp, and the closed space Sp is filled with the liquid.

  The processing container 56 is formed with a supply port 61 for supplying the liquid 60 and a discharge port 62 for discharging the liquid 60 supplied to the closed space Sp of the processing container 53 to the outside. A supply pipe 63 is connected to the supply port 61, and the supply pipe 63 is connected to the liquid supply source 54 via a valve 64. The valve 64 opens and closes the conduit of the supply pipe 63 and adjusts the flow rate of the liquid 60 supplied from the liquid supply source 54. A discharge pipe 65 is connected to the discharge port 62, and a valve 66 is connected to the discharge pipe 65. The valve 66 opens and closes the conduit of the discharge pipe 66 and adjusts the flow rate of the liquid 60 discharged from the processing container 56. The liquid supply source 54 adjusts the liquid 60 to a predetermined pressure and flow rate and supplies the liquid 60 to the processing container 56. The liquid 60 supplied from the liquid supply source 54 is a liquid that transmits the laser beam LB. For example, water is used.

However, in the current display device, the size of the substrate is increased in order to improve the yield, and 2 meters □ are planned. For this reason, it is unavoidable to increase the size of the equipment by the above method. Therefore, according to the configuration described in the above-mentioned Patent Document 5, a large processing container 56 is required to accommodate the enlarged workpiece 51, and the design pattern rule of the next generation display will be less than 2 microns. In the configuration in which the circuit pattern is further miniaturized and the entire workpiece 51 is wrapped with the liquid 6, it is inevitable that the debris mixed in the liquid 60 is reattached to other patterns. There was a problem that costs and material costs would be consumed.
JP 2004-153171 A Japanese Patent Laid-Open No. 9-271980 Japanese Patent Laid-Open No. 10-99978 JP-A-9-141480 JP 2003-245791 A

  The present invention has been made to solve the above-mentioned problems, and the problem to be solved by the present invention is that a liquid such as water is locally applied to the pattern of the surface to be processed of the workpiece to be ablated. By irradiating the surface of the object to be processed with this immersed liquid, the generated debris is suspended in the liquid, and the debris is washed away together with the liquid after the processing is completed. It is an object of the present invention to obtain a laser processing apparatus, a processing method thereof, a debris recovery apparatus, and a recovery method thereof that are prevented from adhering.

  The first object of the present invention is to suppress minute particles such as debris, dross, mist, and fumes that are scattered in the liquid during laser irradiation, and to reattach the debris to the substrate or projection lens of the workpiece. There is no laser processing device and its processing method and debris recovery device and its recovery method.

  The second object of the present invention is to provide a liquid immersion portion by the surface tension of the liquid in order to supply / recover (discharge) the liquid supplied between the projection optical system terminal portion (projection lens) and the substrate of the workpiece. The liquid immersion type laser processing apparatus formed, a processing method thereof, a debris recovery apparatus, and a recovery method thereof are obtained.

  A third object of the present invention is to obtain a laser processing apparatus, a processing method thereof, a debris recovery apparatus, and a recovery method thereof, in which a liquid is immersed only locally on a substrate to be processed.

  A fourth object of the present invention is to provide a laser processing apparatus that recovers debris by forming a liquid immersion portion only in a local area where patterning of a laser irradiation surface of a substrate to be processed is performed, and a processing method and debris recovery thereof. To obtain the device and its recovery method.

  A laser processing apparatus according to a first aspect of the present invention is a laser processing apparatus that removes and collects debris generated by irradiation of laser light during patterning of a transparent resin layer formed on an object to be processed. A debris collection unit that irradiates a laser beam from above the object and is disposed above the object to be processed, a projection optical system terminal disposed in the debris collection unit, and a surface to be processed of the object to be processed A liquid delivery means for passing a liquid between them, and the work surface of the work piece is locally immersed in the liquid so as to absorb and collect minute particles such as debris, dross, mist, and fume. It is a thing.

  The laser processing method according to the second aspect of the present invention includes debris, dross, mist, fume, etc. generated by laser light irradiation during patterning processing of a transparent resin layer, a resin film, and a metal thin film formed on a workpiece. In a laser processing method for removing and collecting minute particles, a laser beam is irradiated from above the object to be processed and a debris collecting means disposed above the object to be processed, and a debris collecting means disposed in the debris collecting means. A liquid feeding means for feeding a liquid between the projection optical system terminal portion provided and the workpiece surface of the workpiece, and locally immersing the workpiece surface of the workpiece by the liquid In this way, fine particles such as debris, dross, mist, and fume are absorbed and recovered.

  The debris collection device of the third aspect of the present invention is a debris, dross, mist, fume, etc. generated by laser light irradiation during patterning of a transparent resin layer, resin film, or metal thin film formed on a workpiece. In a debris collection device that removes and collects microparticles, a laser beam is irradiated from above the object to be processed, and a debris collection means disposed above the object to be processed, and disposed in the debris collection means. And a liquid feeding means for feeding a liquid between the projection optical system terminal portion and the workpiece surface of the workpiece, and the workpiece surface of the workpiece is locally immersed in the liquid. In this way, fine particles such as debris, dross, mist, and fume are absorbed and recovered.

  The debris collection method of the fourth aspect of the present invention is a debris collection method that removes and collects debris generated by laser light irradiation during patterning of a transparent resin layer, resin film, and metal thin film formed on a workpiece. In this case, the debris collecting means that is irradiated with laser light from above the workpiece and disposed on the top of the workpiece, the projection optical system terminal portion disposed in the debris collecting means, and the workpiece Liquid feeding means for passing a liquid between the work surfaces of the object, and the work surface of the work object is locally immersed in the liquid so that a minute amount of debris, dross, mist, fume, etc. Particles are absorbed and recovered.

According to the present invention, it is possible to provide a laser processing apparatus, a processing method thereof, a debris recovery apparatus, and a recovery method thereof having the following effects.
1. It is possible to prevent fine particles such as debris, dross, mist, and fumes generated during ablation processing by laser light from being reattached to the surface of the workpiece.
2. An optical system that optically projects a laser beam emitted from a laser light source onto the work surface of an object to be processed. The final optical system (projection lens system or cover lens) and the surface to be processed are slightly In particular, the liquid immersion circulation type debris collection means capable of supplying and collecting the liquid that transmits the laser does not affect the pattern where the debris comes close by the laser irradiation, so that the fine processing becomes possible.
3. When patterning fine processing by laser irradiation, a high NA is required for the projection lens of the optical system, so that the distance (work distance) between the final optical system and the workpiece surface becomes close. For this reason, it is possible to prevent a phenomenon (secondary contamination) that the final optical system is contaminated by the vapor substance or the scattered matter ablated from the processing surface of the processing object by the laser light irradiation.
By 4.2, it becomes easy to collect the surface material to be processed that is finely scattered by laser irradiation. For example, ITO film pieces such as rare metals can be collected and recycled.
5. Debris can be collected without creating a large-sized holding mechanism for preventing debris adhesion.

  An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an overall conceptual diagram showing an embodiment of a gas laser processing apparatus of the present invention, FIG. 2 is an overall conceptual diagram showing an embodiment of a solid-state laser processing apparatus of the present invention, and FIG. 3 is a laser processing apparatus of the present invention. 4 is a cross-sectional view of the projection immersion system solution immersion circulation mechanism of FIG. 4, FIG. 4 is a cross-sectional view of the main part for explaining the operation of the debris collection mechanism of the laser processing apparatus of the present invention, and FIG. FIG.

  In the present invention, when a transparent resin layer such as a transparent conductive film is formed on a multilayer film formed on a glass substrate which is an object to be processed, the surface of the transparent resin layer is irradiated with laser light from the upper surface, and ablation is performed. Laser processing apparatus, laser processing method, and debris collection apparatus for removing and recovering debris by locally immersing a solution of debris, which is a scattered material generated during laser processing by heat melting or their combined action, in a patterning portion of a substrate And a method for collecting the same.

  An embodiment of the laser processing apparatus of the present invention will be described below with reference to FIG. FIG. 1 shows a schematic laser optical system and a debris recovery apparatus according to the present invention. In FIG. 1, reference numeral 15 denotes an immersion circulation type gas laser processing apparatus, which emits from a gas laser oscillator 11 having a gas laser light source. The laser beam 16 has its optical path bent at right angles via the mirror 10 and is flattened so that the energy from the laser light source becomes uniform through, for example, the flattening optical system 9 including a homogenizing optical system and a diffraction grating. Is done. The laser beam 16 is shaped into a laser beam 17 of a desired size by a mask or variable aperture 8 that determines the size of the laser beam 16. The laser beam 17 whose size is determined by the mask or the variable aperture 8 is reduced and condensed by the optical projection lens groups 18, 19, 720, 21, etc. in the projection lens unit 7 and placed on the XY stage 1. The transparent resin layer 22 formed on the multilayer film on the surface of the substrate 2 is irradiated from above the substrate 2 such as glass. Between the projection lens unit 7 disposed above the substrate 2 and the transparent resin layer 22, a projection optical system termination unit / liquid immersion circulation mechanism (hereinafter referred to as a debris collection unit) 4 constituting the debris collection device is installed. The debris 12 generated from the generated transparent resin layer 22 is collected by the debris collection unit 4.

  A deple collecting unit 4 formed of a substantially funnel-shaped housing formed in a manner connected to a projection lens unit 7 having a substantially cylindrical housing has a liquid supply port 5 for supplying the liquid 3 and a liquid drain for discharging the liquid 3. An outlet 6 is provided. Similarly to FIG. 6, the liquid 3 is supplied from the liquid supply source 54 to the liquid supply port 5 through a valve 64 (not shown). The liquid 3 from the liquid supply port 5 enters the funnel-shaped housing wall of the debris collection unit 4 as shown in FIG. 3 of the schematic diagram of the immersion type debris collection mechanism and FIGS. 4 and 5 showing the operation mechanism of the debris collection mechanism. A discharge rod communicating with the liquid discharge port 6 through the formed liquid supply unit 5 through the supply path 13 and passing through the lower end of the terminal lens 21 of the optical system fitted on the opening 23 formed at the bottom of the debris collection unit 4. 14 is discharged. At this time, the liquid 3 is applied to the lower end of the opening 23 between the transparent resin layer 22 of the substrate 2 on the XY stage 1 and the lens 21 (see FIG. 3) at the optical system terminal portion disposed in the deple collection unit 4. A liquid immersion part 24 that is held by surface tension in the immersed state is configured.

  Here, the operation of the mechanism of the immersion circulation type debris collection unit 4 will be specifically described. A fixed amount of liquid 3 is supplied from the liquid supply port 5 into the space of the opening 23 in which the distance between the terminal lens 21 of the optical projection lens group 18, 19, 20, 21 and the transparent resin layer 22 on the substrate 2 is kept constant. In addition, the same amount of the liquid 3 is discharged from the liquid discharge port 6, and the liquid 3 is moved on the processing surface on the substrate 2 to maintain the state of the liquid immersion unit 24. Although not shown, the liquid supply port 5 is provided with a flow rate pump having a flow rate adjusting function, and the liquid discharge port 6 is provided with a discharge pump. While maintaining the continuous operation of the liquid immersion part 24 by the liquid immersion circulation, the laser beam 17 is irradiated to wash away the debris 12 generated by the ablation process, and the processed surface of the transparent resin layer 22 on the substrate 2 by the liquid discharge port 6. It is made to maintain the above cleanliness.

  In the above-described immersion circulation type gas laser processing apparatus 15, the laser light 16 from the gas laser oscillator 11 of FIG. 1 passes through the mirror 10 through the flattening optical system 9 such as homogenization, and is then applied to the mask or A laser beam 17 patterned into an arbitrary shape by the variable aperture 8 emits a laser beam onto the transparent resin layer 22 that is the processing surface of the substrate 2 through the optical projection lens groups 18, 19, 20, and 21 of the projection lens unit 7. Irradiate. At this time, the terminal lens 21 of the optical projection lens group 18, 19, 20, 21 of the debris collection unit 4 is set so that the pattern or size of the pattern of the mask or variable aperture 8 matches the reduction ratio of the projection lens in advance. By controlling the height (position) of the laser beam 17, the laser beam 17 is focused on the transparent resin layer 22 on the processed surface of the substrate 2, and the terminal lens 21 of the optical projection lens group and the transparent resin layer 22 on the substrate 2 are aligned. The working distance (hereinafter referred to as WD), which is the distance, is kept constant.

For example, the numerical aperture NA of the optical projection lens (the numerical aperture is determined by the lens diameter r and the focal length f of the objective lens, where NA = n × sin θ, where n is the refractive index of the optical path, θ is the focal length and the lens diameter θ. = Tan ⁻¹ (r / f)), the depth of focus is d = λ / (2 × NA × NA). In this example, the liquid immersion part 24 is a state in which the above-mentioned WD is about 50 microns to 5 millimeters and is balanced by the surface tension between the WDs. The liquid 3 used in the liquid immersion unit 22 has a refractive index of 1 or more, and for example, pure water (refractive index = 1.14) can be used. In addition, it is obvious that the liquid having good wavelength transmittance of the laser beam 16 to be used and liquid or water-soluble resin or surfactant may be contained to control the viscosity or wettability.

As the gas laser light source of the gas laser oscillator 11 shown in FIG. 1, for example, an excimer laser or the like can be used. There are a plurality of types of excimer lasers with different laser media, and XeF (351 nm), XeCl (308 nm), KrF (248 nm), ArF (193 nm), and F ₂ (157 nm) exist from the longer wavelength. However, the laser source is not limited to the excimer laser and may be a solid-state laser or the like as shown in FIG. The smoothing optical system 9 shapes the laser light 16 from the laser light source reflected by the mirror 10, equalizes the beam intensity, and outputs it. For example, the variable aperture 8 is a perforated aperture mask of a predetermined aperture made of a metal material, a photomask formed of a transparent glass material or a metal thin film, or a dielectric mask or aperture formed of a dielectric material. Possible variable apertures are used. The excimer laser dissociates the photochemical direct bond, called ablation, and performs processing that is not easily affected by heat, so that the edge of the processed surface is very sharp. On the other hand, a YAG laser (1.06 μm), a CO 2 laser (1.06 μm), or the like that performs laser processing using thermal energy involves evaporation after thermal melting, and the amount of debris generated increases.

  In the gas laser processing apparatus 15 having the configuration shown in FIG. 1, an excimer laser is used for the laser oscillator 11 to irradiate the processing surface of the substrate 2 as a processing target with a laser beam having a predetermined pattern. The processed surface on the substrate 2 is ablated between the substrate 2 and the substrate 2 through the immersion circulation mechanism unit (debris recovery unit) 4 via the liquid immersion unit 22. As shown in FIG. The solid-state laser beam 16 obtained by flattening the laser beam 16 from the laser beam 16 with the homogenization optical system 9a may be used. This solid-state laser light 16 is bent so as to be substantially orthogonal to a shaft 28 by a galvano mirror 26 that can be swung by a driving source such as a motor, and along the pattern of the transparent resin layer 22 on the substrate 2, for example, X Scanned in the axial direction. The laser beam 17 that has passed through the objective lens 29 passes through the liquid immersion lens 24 formed on the transparent tree layer 22 on the substrate 2 through the optical projection lens groups 18, 19, 20, and 21 shown in FIG. Predetermined patterning is performed on the surface to be processed. In FIG. 2, even when a semiconductor laser is used as the immersion circulation type solid-state laser processing apparatus 30, the immersion type debris collection unit 4 can be used, and etching reaction mechanisms (thermal melting) according to various lasers and wavelengths. Debris and dross generated by photochemical reaction, ablation, explosion phenomenon (film collapse), multiphoton absorption) can be exhibited.

  Of course, also in this case, as shown in the enlarged view of FIG. 5, it fits on the opening 23 formed in the bottom of the debris collection unit 4 through the supply path 13 formed in the funnel-shaped wall of the debris collection unit 4. The liquid is discharged to a discharge rod 14 communicating with the liquid discharge port 6 through the lower end of the terminal lens 21 of the optical system. At this time, the liquid 3 is applied to the lower end of the opening 23 between the transparent resin layer 22 of the substrate 2 on the XY stage 1 and the lens 21 (see FIG. 3) at the optical system terminal portion disposed in the deple collection unit 4. In the liquid immersion part 24 held by the surface tension in the immersed state, the debris 12 generated by the application of the irradiation of the laser beam 17 is discharged into the liquid immersion part 24 and liquid is supplied from the liquid supply source 54 (see FIG. 6). It flows into the liquid 3 that is supplied to the supply port 5 and circulates in the opening 13 through the supply path 13, and is sent to the debris collection device (not shown) via the discharge path 14 and the liquid discharge port 6.

According to the laser processing apparatus, the processing method thereof, the debris recovery apparatus, and the recovery method irradiation of the present invention, the following effects are achieved.
1. It is possible to prevent fine particles such as debris, dross, mist, and fumes generated during ablation processing by laser light from being reattached to the surface of the workpiece.
2. An optical system that optically projects a laser beam emitted from a laser light source onto the work surface of an object to be processed. The final optical system (projection lens system or cover lens) and the surface to be processed are slightly In particular, the liquid immersion circulation type debris collection means capable of supplying and collecting the liquid that transmits the laser does not affect the pattern where the debris comes close by the laser irradiation, so that the fine processing becomes possible.
3. When patterning fine processing by laser irradiation, a high NA is required for the projection lens of the optical system, so that the distance (work distance) between the final optical system and the workpiece surface becomes close. For this reason, it is possible to prevent a phenomenon (secondary contamination) that the final optical system is contaminated by the vapor substance or the scattered matter ablated from the processing surface of the processing object by the laser light irradiation.
By 4.2, it becomes easy to collect the surface material to be processed that is finely scattered by laser irradiation. For example, ITO film pieces such as rare metals can be collected and recycled.
5. Debris can be collected without creating a large-sized holding mechanism for preventing debris adhesion.

It is a whole block diagram which shows one example of a laser processing apparatus of this invention. It is a whole block diagram which shows the other example of a laser processing apparatus of this invention. It is sectional drawing of the liquid immersion circulation mechanism of the projection optical system termination | terminus part of the laser processing apparatus of this invention. It is principal part sectional drawing for operation | movement description of the debris collection | recovery mechanism of the laser processing apparatus of this invention. 5 is a plan view taken along the line AA in FIG. It is a schematic block diagram which shows one example of a conventional laser processing apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... XY stage, 2 ... Board | substrate, 3 ... Liquid (water), 4 ... Projection optical system termination | terminus part and immersion circulation mechanism (debris collection | recovery part), 5 ... Liquid supply port, 6 ... liquid discharge port, 7 ... projection lens unit, 8 ... mask or variable aperture, 9 ... averaging optical system, 9a ... homogenizing optical system, 10 ... mirror, 11. ..Gas laser oscillator, 12 ... debris, 13 ... supply path, 14 ... discharge path, 15 ... immersion circulation type gas laser processing apparatus, 16 ... laser beam, 17 ... laser beam , 18, 19, 20, 21 (terminal lens): optical projection lens group, 22: transparent resin layer, 23 ... opening, 24 ... liquid immersion part, 25 ... solid laser oscillator 26 ... Galvano mirror

Claims (8)

In a laser processing device that removes and collects microparticles such as debris, dross, mist, and fumes generated by laser light irradiation during patterning of transparent resin layers, resin layers, and metal layers formed on the workpiece. And debris recovery means that irradiates the laser beam from above the workpiece and is disposed on top of the workpiece.
Liquid passing means for passing liquid between the projection optical system terminal portion disposed in the debris collecting means and the processing surface of the workpiece;
The laser processing apparatus is characterized in that the processing surface of the processing object is locally immersed in the liquid to absorb and recover debris. A laser processing method that removes and collects microparticles such as debris, dross, mist, and fumes generated by laser light irradiation during patterning of transparent resin layers, resin layers, metal layers, etc. formed on the workpiece. In
Debris collection means for irradiating the laser beam from above the workpiece and disposing the laser beam on the workpiece;
Liquid passing means for passing liquid between the projection optical system terminal portion disposed in the debris collecting means and the processing surface of the workpiece;
Comprising
A laser processing method characterized by absorbing and collecting minute particles such as debris, dross, mist, and fume by locally immersing the processing surface of the processing object with the liquid. In a debris collection device that removes and collects debris generated by laser light irradiation during patterning of transparent resin layers, resin layers, metal layers, etc. formed on the workpiece,
The laser beam is irradiated from above the object to be processed and the debris collecting means disposed above the object to be processed, the projection optical system terminal section disposed in the debris collecting means, and the object to be processed Liquid passing means for passing liquid between the workpiece surfaces of the workpiece;
A debris collection apparatus, wherein the work surface of the work object is locally immersed in the liquid to absorb and collect debris. In a debris collection method for removing and collecting debris generated by laser light irradiation during patterning processing of a transparent resin layer, resin layer, metal layer, etc. formed on a workpiece,
Debris collection means for irradiating the laser beam from above the workpiece and disposing the laser beam on the workpiece;
A liquid sending means for sending a liquid between a projection optical system terminal portion disposed in the debris collecting means and a work surface of the work object;
A debris collection method characterized by absorbing and collecting fine particles such as debris, dross, mist, and fume by locally immersing the work surface of the work object with the liquid.   The laser processing apparatus according to claim 1, wherein a local portion where the processing surface of the processing object is locally immersed by the liquid is a local portion of the laser irradiation surface.   The laser processing method according to claim 2, wherein a local portion where the processing surface of the processing object is locally immersed by the liquid is a local portion of the laser irradiation surface.   4. The debris collection apparatus according to claim 3, wherein a local portion where the processing surface of the processing object is locally immersed by the liquid is a local portion of the laser irradiation surface.   The debris collection method according to claim 4, wherein a local portion where the processing surface of the processing object is locally immersed by the liquid is a local portion of the laser irradiation surface.

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