KR100773667B1 - Laser-assisted etching process and apparatus utilizing an optical fiber as a light delivery and micromachining tool - Google Patents

Abstract

A laser-assisted etching process and an apparatus utilizing an optical fiber as a light transmitting and micromachining tool are provided to remove the inconvenience of an optical alignment and to solve the danger due to the exposure of a laser beam. A laser-assisted etching process utilizing an optical fiber as a light transmitting and micromachining tool includes the steps of: generating a laser beam; transmitting the generated laser beam to a workpiece through the optical fiber; radiating the laser beam to a processing part of the workpiece through the optical fiber; and inserting an end of the optical fiber radiating the laser beam inside the processing part of the workpiece. The laser-assisted etching method processes the workpiece by radiating the laser beam to the workpiece in an etching solution to induce the smooth chemical reaction between the workpiece and the etching solution.

Description

Laser-assisted etching process and apparatus utilizing an optical fiber as a light delivery and micromachining tool

1 is a block diagram showing an example of a laser etching apparatus developed by the inventors prior to the present invention;

2 is an explanatory diagram for explaining the basic principle of laser etching;

3 is a process diagram of laser etching,

4 is a block diagram showing the configuration of a laser etching apparatus according to the present invention;

5 is a graph showing a minimum separation distance between an optical fiber end and a workpiece surface according to a change in laser power;

6 and 7 are photographs of microstructures processed using a laser etching apparatus using an optical fiber according to the present invention as a light transmission and processing tool,

8 is a plan view showing an example of the high-rigidity microchannel processed according to the present invention,

9 is a cross-sectional view of a cross-sectional view of the microchannel of FIG. 8;

10 is a view showing in sequence the process of manufacturing micro holes while reducing the processing time according to the present invention,

11 is a view showing an example in which a lens-type optical fiber is installed at the end of the optical fiber,

12 and 13 illustrate an example in which a laser beam is divided into several parts using an optical splitter or an optical combiner.

Explanation of symbols on the main parts of the drawings

300: laser 310: objective lens

320, 346, 360: microfeed system 330, 902, 904, 912: optical fiber

340: fixing jig 342: optical fiber ferrule

344: support 350: chamber

352: workpiece 354: etching solution

356 pump 358 tube

370: motor drive unit 380: computer

390: camera 800: lenticular optical fiber

900: optical coupler 910: optical splitter

The present invention relates to a laser etching method and apparatus thereof, and in particular, to irradiate the workpiece in the etching solution with a laser beam to induce a chemical reaction between the workpiece and the etching solution in the portion to which the laser beam is irradiated to facilitate the workpiece. The present invention relates to a laser etching method and an apparatus for processing the same.

Microstructures, such as holes or channels, ranging in size from hundreds to hundreds of micrometers, are micro-reactors and micro-fluidic devices that are components of the rapidly growing fields of information communication, biotechnology, and micromeasuring Corresponds to the core structure of micro thermal / fluidic devices such as fluidic devices and micro heat pipes. The manufacturing technology of such microstructures has been developed in various ways for high integration and high performance of micro devices with the development of micro electromechanical system (MEMS) technology. The development of ultra-precision raw technology for many micro holes and channels is expected to contribute to the development and advancement of related industries.

Microstructures made of small diameters, widths, and deep holes and channels can have large capillary pressures in them, so that micro devices can be operated without a separate driving power. It has the advantage that it can be used as. Therefore, there is a need for an ultra-precision machining technology capable of uniformly and deeply processing hole and channel structures of several to several hundred micrometers on various materials. Currently, ultra-precision processing technologies used in various industries include machining, semiconductor and MEMS processes, electron beam processing, X-ray lithography (LIGA) processes, laser ablation, and laser etching. The areas used are also different because they have disadvantages.

Machining, which has the disadvantage of tool numerical limits, makes it difficult to fabricate structures up to tens of micrometers and has the major disadvantage of tool wear or breakage. On the other hand, it is difficult to overcome the material limitation that semiconductor and MEMS processes capable of ultra-fine processing of several micrometers are for forming a structure on a silicon substrate, and especially thick metal sheets, for example, about 100 micrometers or more. There is a disadvantage that it is difficult to process. In addition, when using an electron beam processing or LIGA process, expensive equipment costs are required because the process is based on a vacuum device and an X-ray generator, respectively. On the other hand, in the case of laser ablation which directly removes the workpiece surface from the air during ultra-precision processing using a laser that does not have material limitations such as metals, semiconductors, and insulators due to its high energy density and excellent workability, The heat affected zone is very large and there is femto-second pulsed laser processing to overcome this problem, but it is not only complicated and expensive, but also easily removes processed residues on the workpiece surface during repeated pulse irradiation. The disadvantage is that it is not.

In contrast, laser-assisted wet etching (hereinafter referred to as laser etching), a method of laser etching, uses a laser as a heat source for a chemical reaction between the workpiece and the etching solution. By inducing a smooth reaction can be produced a structure of a clean shape having no heat affected zone compared to the processing by laser ablation, processing by-products can be effectively removed by the flow of micro-bubbles generated during processing. In addition, it is possible to freely process structures ranging from several hundreds to hundreds of micrometers according to process variables such as laser power, focusing speed, and concentration of etching solution. Has the advantage.

Today's microdevices require not only their size to be smaller, but also more efficient and higher performance as the system becomes smaller and more integrated. Accordingly, microstructures ranging from tens to tens of micrometers, particularly micro holes and channel processing, are required for ultra-small, high-performance micro devices. In the case of electric discharge machining, which is most widely used for micro machining, tools have to be manufactured in advance according to the size of the structure to be finalized. Once used, tools cannot be reused, which is expensive and time-consuming, and can cause tool breakage when machining difficult materials such as stainless steel.

On the other hand, in the case of the processing using laser etching, there is no fear of tool wear as in the electric discharge machining or the machining because it is a non-contact processing using the laser beam, and the laser beam is used to induce the thermochemical reaction between the workpiece and the etching solution. Processing takes place. In laser etching, the workpiece is cooled by the convective heat transfer of the etching solution, so it is possible to obtain an excellent processing surface without heat deformation or heat affected zone of the processing material. Precise and uniform structure can be machined with width or diameter divided by

1 is a block diagram showing an example of a laser etching apparatus developed by the present inventors prior to the present invention.

The laser etching apparatus of FIG. 1 is largely composed of a laser unit 102, an optical system 104, a transfer system 106, and a control unit 108. Here, the laser unit 102 and the optical system 104 can be seen as a laser beam irradiator.

In FIG. 1, the laser beam from the laser 100 first passes through the beam expander 110 to enhance the protection efficiency of the optical system 104 in the path and the focusing efficiency on the surface of the workpiece material 180. The beam 120 enlarged by the beam expander 110 passes through the reflector 130, the linear polarizer 140, and the quarter-wave plate 150, and then becomes a circularly polarized state. And incident on the surface of the material thin plate 180. At this time, the linear polarizer 140 and the quarter-wave plate 150 is installed on the beam path to make the laser beam circularly polarized. The beam reflected from the surface of the material thin plate 180 is transferred to the laser 100. In order to prevent the damage to the laser (100) to enter again and at the same time to minimize the change of the processing result according to the polarization state. The chamber 170 containing the etching solution and the processing material thin plate 180 is placed on the XYZ micro-feed system 190 equipped with a motor having a precision of 1 micrometer, and made of Teflon material to prevent chemical reactions. It is preferable that it is produced. The X-Y-Z micro feed system 190 is operated by the motor driving device 220 and the feed path of the chamber 170 and the processing material thin plate 180 is controlled through a feed system control program installed in the control means 230. A computer is suitable as the control means 230. In addition, during the etching process, the etching solution is transferred from the etching solution reservoir 200 to the chamber 170 by using the peristaltic pump 210 to effectively remove the microbubbles generated during the processing and supply of sufficient etching solution. The entire process of etching the processing material thin plate 180 is observed on a monitor connected to the control means 230 through the CD camera 240 installed on the reflector 130.

The laser etching apparatus of FIG. 1 requires a beam enlarger to make smaller focused beams on the workpiece surface, and in the case of metal workpieces, since the laser beam reflected from the surface may be transferred back to the laser system to damage the device. Additional configuration of the linear polarizer and the quarter wave plate allows the laser beam to pass through in only one direction.

In the laser etching apparatus composed of such complicated optical systems, when the laser beam is delivered to the workpiece, the laser etching apparatus passes through complicated optical systems such as a beam magnifier, a linear polarizer, a quarter-wave plate, and an objective lens for a microscope. If the alignment is disturbed, it is inconvenient to realign it each time.

In addition, each of the optical systems finely reflects or scatters the laser beam, which increases the likelihood that the operator will be exposed to the path, thereby increasing the risk of the reflected or scattered laser beam penetrating the operator's eyes.

In addition, many components have the disadvantage that the size of the equipment is large, manufacturing cost is high, and design change is difficult.

In addition, since only one beam is used at a time, there is a disadvantage in that the processing speed and productivity are inferior.

That is, the laser etching apparatus as shown in FIG. 1 needs to be further improved.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laser etching method which is less likely to disturb the light alignment.

Another object of the present invention is to provide a laser etching method having a low risk of worker exposure to the laser beam reflected or scattered on the surface of the optical system.

Still another object of the present invention is to provide a laser etching method having an improved processing speed.

It is still another object of the present invention to provide a laser etching method capable of reducing the number of parts of an apparatus.

Another object of the present invention is to provide a laser etching apparatus for implementing the method of the present invention.

The laser etching method according to the present invention irradiates a laser beam to a workpiece in an etching solution to induce a chemical reaction between the workpiece and the etching solution in a portion to which the laser beam is irradiated so that the workpiece is processed. A laser etching method, comprising: a laser beam generation step of generating a laser beam, a laser beam transmission step through an optical fiber for transmitting the generated laser beam toward the workpiece through an optical fiber, and the laser beam transmitted toward the workpiece And a laser beam irradiation step through the optical fiber for irradiating the laser beam to the portion to be processed through the optical fiber to be processed.

It is preferable to further include an optical fiber insertion step of inserting the optical fiber end from which the laser beam is emitted into the processing unit formed in the workpiece by the laser beam irradiation step.

More preferably, further comprises a vertical movement step of moving the end of the optical fiber or the workpiece to the laser beam is emitted.

In some cases, the method may further include branching the laser beam into two or more optical fibers.

The method may further include a laser beam focusing step of focusing the laser beam emitted from the optical fiber into the lens-type optical fiber.

Etching solution circulation step of circulating the etching solution in the chamber, photographing the process of processing the workpiece by the laser beam irradiated to the workpiece and the step of outputting the photographed to the display It is good.

The laser etching apparatus according to the present invention irradiates a laser beam to a workpiece in an etching solution contained in a chamber to induce a chemical reaction between the workpiece and the etching solution in the portion to which the laser beam is irradiated to smoothly occur. A laser etching apparatus for processing a laser beam, comprising: a laser for generating a laser beam, a laser beam generated by the laser, receiving the laser beam, and transferring the received laser beam toward the workpiece to output the portion to be processed; An optical fiber for irradiating the laser beam and a micro-feed system for relatively moving the end of the optical fiber from which the laser beam is emitted and the workpiece relative to each other.

The optical fiber end from which the laser beam is emitted is mounted on an optical fiber ferrule which is not corroded to the etching solution, and the microfeed system is a first microfeed system for transferring the end of the optical fiber, and the ferrule is held by the first microfeed system. It is preferable that the jig is provided.

Preferably, the first micro feed system is driven by a precision motor, the motor drive device is connected to the first micro feed system, and the motor drive device is connected to a computer on which a control program of the motor drive device is installed.

In some cases, the microfeed system may be a second microfeed system for microfeeding the chamber, and the chamber may have a configuration in which a pump and a circulation pipe for circulating the etching solution in the chamber are installed.

Of course, the microfeed system is preferably installed in both.

One side of the chamber is formed with a transparent portion, the outside of the transparent portion is provided with a camera for photographing the inside of the chamber, the camera is more preferably connected to a computer having a display to check the processing process. .

More preferably, one end of the optical fiber to which the laser beam is incident is provided with a third fine transfer system for adjusting the position of one end of the optical fiber.

Preferably, an objective lens for focusing the laser beam generated by the laser and entering the one end of the optical fiber is disposed between the laser and one end of the optical fiber to which the laser beam is incident.

It is preferable that an optical coupler or a splitter is installed at the end of the optical fiber from which the laser beam is emitted, and two or more other optical fibers are installed in the optical coupler or the splitter.

In some cases, a lens type optical fiber may be installed at the end of the optical fiber from which the laser beam is emitted.

In other cases, the other optical fibers may be lens-type optical fibers.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiment of the present invention describes the application of the present invention to a metal sheet having advantages such as corrosion resistance, high strength, high heat transfer coefficient, and excellent moldability, but the present invention in principle increases the mutual responsiveness when the temperature is increased. Any etching solution and material can be applied.

In addition, it is a relatively simple process that allows direct removal of material and structure formation at the same time in the laser beam irradiation area, and it reduces the processing time and manufacturing method of high-aspect-ratio micro holes with high ratio of width to depth. A new etching technique that can be described is described. It also describes how to increase the processing yield by applying various optical fiber devices to the system.

Among the disadvantages of laser etching, the present invention is intended to eliminate the risk of light alignment due to the complicated optical system configuration and the risk of exposure of the laser beam and to facilitate the convenience of the operator. By replacing the optical fiber, it is possible to solve the problem of optical alignment, and the laser beam passes only inside the optical fiber, thereby reducing the risk of exposure of the laser beam to the operator, and using various types of optical fiber components in the middle or the end of the optical fiber. By providing a technology that can improve the processing productivity and processing precision. The technology of the present invention is expected to contribute to industrial development by providing efficient ultra-precision machining source technology that enables the processing of microstructures of several tens to tens of micrometers in size.

2 is an explanatory diagram for explaining the basic principle of laser etching, Figure 3 is a process diagram of laser etching.

That is, the laser beam 120 focused by the optical system is irradiated to the minute processing area on the workpiece 182, and at this time, the workpiece 182 absorbs laser energy as a heat source and is locally heated. Since the laser beam used as the heat source should not be absorbed by the etching solution 172, it is advantageous to use a laser beam having a wavelength in the visible or infrared region. However, an infrared laser beam having a long wavelength has a disadvantage in that processing efficiency is much lowered due to large energy loss due to large reflectance on the metal surface. The absorption of laser energy causes a chemical reaction between the heated workpiece 183 and the etching solution 172 to selectively remove the material of the portion where the laser beam is irradiated and to remove the etching solution 172 and the workpiece. By-products 185 are produced by the chemical reaction of the particles 183. This process finally produces the desired structure. In order to manufacture micro holes and channels of high-grade equipment, it is difficult to obtain a structure having a desired dimension with only one etching, and it is necessary to repeatedly etch the same position several times or gradually move the laser focus in the depth direction as the processing progresses.

Figure 4 is a block diagram showing the configuration of a laser etching apparatus according to the present invention, Figure 5 is a graph showing the minimum separation distance between the optical fiber end and the workpiece surface according to the change in the laser output.

The present invention is to solve the shortcomings of the conventional laser etching apparatus, as shown in Figure 4 by using the optical fiber 330, the laser beam from the laser 300 is transmitted to the workpiece 352 surface at once.

In the present invention, unlike the use of a microscope objective for the laser beam focusing on the surface of the workpiece material plate 180, which is the workpiece in the conventional apparatus described with reference to FIG. 1, the diameter of the optical fiber ends is usually less than 125 micrometers Focusing on the small size, light emitted from the end of the optical fiber is directly irradiated onto the workpiece 352 or by connecting the lens-type optical fiber to the end of the optical fiber 330 to allow finer processing.

In the present invention, by using the optical fiber 330 for the light transmission to eliminate the possibility that the operator can be exposed to the laser beam, there is no hassle of light alignment by using the optical fiber 330 itself as a processing tool.

In general, the optical fiber 330 is divided into a single mode optical fiber and a multi mode optical fiber, but in the present invention, both cases may be applied. In other words, when the single mode optical fiber is used, the incident light loss is rather large, but precise processing is possible because a laser beam having a very good shape is output at the output end.

In the case of using multi-mode optical fiber, since several modes are transmitted at the same time, the quality is somewhat lower than that of the beam transmitted through the single-mode optical fiber, but the optical loss is relatively low, so processing using high optical power is possible. Is advantageous in

The laser beam oscillated from the laser 300 is incident on the core portion of the optical fiber 330 through the microscope objective lens 310. At this time, the optical fiber 330 is attached to the passive X-Y-Z micro-feed system 320 to adjust the position in order to enter the focused beam without loss. The ends of the optical fiber 330 used for processing are mounted on the optical fiber ferrule 342 which is not easily corroded to the etching solution and protrude about 1 to 2 mm for insertion into the workpiece 352. The optical fiber ferrule 342 is mounted vertically to the fixing jig 340, and the fixing jig 340 is fixed to the support 344 for mounting to the X-Y-Z micro feed system 346. An X-Y-Z micro-feed system 346 driven by a motor with a precision of 1 micrometer is used to transport the ends of the optical fiber 330 to the exact position and depth of the workpiece 352 surface. The X-Y-Z micro feed system 346 is operated by the motor driving device 370 and controls the end of the optical fiber 330 to reach the desired position accurately through the feed system control device installed in the computer 380. The chamber 350 containing the workpiece 352 and the etching solution 354 is made of Teflon and fixed on the X-Y-Z micro-feeding system 360 to prevent chemical reaction with the etching solution. The X-Y-Z micro feed system 360 may use either a motor drive type or a manual type.

 One side of the chamber 350 may be a transparent material so that the process of etching may be performed and the initial distance between the end of the optical fiber 330 and the surface of the workpiece 352 may be observed by a charge coupled device (CCD) camera 390. For example, it is preferable to be made of a material such as quartz. In addition, in order to effectively remove the microbubbles generated during the supply and processing of the sufficient etching solution 354 during the etching process, around the end of the processing unit and the optical fiber 330, the peristaltic pump 356 and the heat-resistant rubber material Viton The etching solution 354 is circulated into the chamber 350 using the tube 358, and the entire process of etching is observed on the monitor of the computer 380 through the CCD camera 390.

When manufacturing a structure of several hundreds to hundreds of micrometers by using a laser etching apparatus using the optical fiber 330 as an optical transmission and processing tool, the most important thing is to be aware of the ends of the optical fiber 330 with respect to the laser output to be processed. How much to maintain the initial separation distance to the workpiece 352 surface. When suddenly supplying laser energy to the workpiece 352 for processing, the ends of the optical fiber 330 may be damaged by the movement or bursting of the bubbles generated essentially. In addition, when the separation distance is too close by a high temperature laser beam, the ends of the optical fiber 330 may be melted or contaminated by adhesion of processing byproducts.

table.

The present invention can be applied to various materials in addition to titanium alloy or stainless steel.

Examples of processing materials that can be processed by the method and apparatus of the present invention and etching solutions corresponding to the materials are shown in the above table.

  In addition to those shown in the table, if the temperature is increased, the present invention can be applied to a material and an etching solution in which etching is activated.

FIG. 5 shows the minimum separation distance between the optical fiber 330 end and the workpiece 352 surface for each change in laser power. For example, if you want to process at an output of 3.5W, the distance between the end of the optical fiber 330 and the workpiece 352 should be maintained at about 250 micrometers or more. As the laser output increases, the separation distance increases, and since the divergence angle of the laser beam emitted from the end of the optical fiber 330 increases, the diameter of the micro hole or the width of the channel also increases.

6 and 7 are photographs of microstructures processed using a laser etching apparatus using the optical fiber according to the present invention as a light transmission and processing tool.

FIG. 6 shows an upper surface 500 of the micro holes, an enlarged picture 502 and a lower surface 510, and an enlarged picture 512 thereof, and FIG. 7 shows a cross section 520 of the workpiece in which the hole shape is shown. Shows. The workpiece 352 used to manufacture the structure is a titanium metal having a thickness of 500 micrometers, which is recently used in aerospace and bio devices because of its corrosion resistance, high strength, and excellent mechanical and biochemical stability.

Using the present invention, precise microstructures can be manufactured in a simple process not only on titanium but also on stainless steel sheets having excellent formability and high thermal conductivity. Among the various process variables in the process of etching the titanium workpiece 352, the micro holes manufactured under the conditions of the optimum laser power, the concentration of the etching solution, the minimum separation distance, etc., have an upper diameter 500 of 150 micrometers and a lower diameter. Since the diameter 510 is 80 micrometers and processed over the entire thickness of the workpiece 352, it has a high fineness of about 5.

The laser etching apparatus using the optical fiber according to the present invention as an optical transmission and processing tool can be applied to deep microchannel processing as well as high-precision micro holes.

8 is a diagram illustrating an example of a high-grade microchannel processed according to the present invention, and FIG. 9 is a cross-sectional view thereof.

The workpiece 352 used in the fabrication of the structure is a 500 micrometer thick stainless steel sheet with excellent formability, high strength and high thermal conductivity. The channel measured at the surface 600 of the workpiece 352 has a shape that maintains a constant width over the entire processed length and has almost no heat affected zone. Referring to the cross section 610 of FIG. 9 showing the cross-sectional shape of the channel, the channel is processed into a V-shaped channel whose width gradually narrows down from the surface to the depth direction, where the intensity of the laser beam is the highest at the center and the edge thereof. This is because the Gaussian distribution becomes weaker gradually, and the most active etching occurs in the center of the channel width. The laser etching apparatus using the optical fiber according to the present invention as a light transmission and processing tool is a stainless steel micro fabricated by appropriately adjusting process parameters such as optimal laser power, concentration of etching solution, minimum separation distance, and transfer speed of laser beam. The channel is about 40 micrometers wide and about 400 micrometers deep, with ten tall devices.

10 is a view sequentially showing a process of manufacturing a micro hole while reducing the processing time according to the present invention.

When the laser beam is irradiated to the workpiece 352 continuously at the position where the optical fiber is fixed, laser energy required for processing is lost due to absorption in the hole and thus cannot be sufficiently transmitted in the depth direction. As a result, the holes to be machined often have a cross-sectional structure of an inverted cone shape. Of course, it is possible to manufacture the desired structure by increasing the processing time, but in this case, the laser beam is irradiated on the surface of the workpiece for a long time to generate a large heat affected zone on the surface of the workpiece or the workpiece 352 may be thermally deformed as a whole. have.

In the present invention, the end of the optical fiber 330 for the first time as shown in the first picture is processed to be located on the surface of the workpiece 352 to produce a slight processing site, and then the end of the fiber 330 as shown in the second picture Machine it by inserting it deeper and deeper into the machined part.

More preferably, the end of the optical fiber 330 is inserted into the processing unit at regular intervals and then detached, and the end of the optical fiber 330 is further inserted inward as shown in the third figure after a predetermined time. Repeat the vertical movement. In this case, since the laser beam is only irradiated to the surface of the workpiece 352 for the first predetermined time, heat affected zone hardly occurs, and when the optical fiber 330 is inserted into the processed portion, the etching by-products present therein can be effectively applied. It has the advantage of being eliminated. In addition, the laser beam is reflected from the internally inclined wall to promote the reaction, thereby making the width of the hole uniform. Through this method, micro holes are finally manufactured as shown in the fourth figure. Compared to the process of fixing and processing the ends of the optical fiber 330, the processing time is reduced by about 1/2 for the same laser output.

One of the advantages of laser etching devices that use optical fibers as optical transmission and processing tools is that they can be processed more efficiently by properly combining several different optical fiber elements with optical fibers.

11 is a view showing an example in which a lens-type optical fiber is installed at the end of the optical fiber.

In order to reduce the size of the microstructure that can be processed, the lens-type optical fiber 800 may be attached to the ends of the optical fiber 330. Lenticular optical fiber 800 is a type of optical fiber device that concentrates the light emitted from the optical fiber because the end of the optical fiber is processed into a lens, and can be manufactured with multimode optical fibers as well as single mode optical fibers. Can be adjusted accordingly. In the case of using a general optical fiber, it is difficult to reduce the size of the processing portion to less than the outer diameter of the optical fiber, but by using the lens-type optical fiber 800, it is possible to make a smaller and more precise processing structure.

12 and 13 illustrate an example in which a laser beam is divided into several parts using an optical splitter or an optical combiner.

 Another advantage of laser etching devices that use optical fibers as light transmission and processing tools is that productivity can be improved by machining several structures of the same size at the same time. One of the disadvantages of laser processing using a focused laser beam is low processing productivity. In the present invention, the optical coupler 900 or the optical splitter 910 of the optical fiber device is properly connected to improve productivity through simultaneous processing. Can be maximized.

That is, as shown in FIG. 12, a 1: 2 optical coupler having other optical fibers 902, 904, and 912 installed at the ends of the optical fiber 330 is connected in series, or an optical splitter 910 such as 1: 4 or 1: 8 is connected. By combining and using high power lasers, laser energy can be distributed and transmitted across multiple optical fibers, and multiple structures of the same size can be manufactured in parallel at the same time using multiple optical fibers.

In some cases, by connecting the lenticular optical fiber 800 to the end of the optical coupler 900 or the optical splitter 910, it is possible to manufacture a precise and uniform microstructure with high productivity.

The present invention is a new technology that enables the processing of micro holes and channel structures that can be used in micro devices such as micro thermal devices and micro fluid devices, which are expected to be actively researched and industrialized, with a simple laser etching device. It not only solves the inconvenience of optical alignment and the risk of exposure of laser beam, but also overcomes the problems such as high cost and difficulty of design change in the ultra-precision processing fields such as semiconductor process, and it is relatively simple method of several hundreds to hundreds of micro Allows the free manufacture of metric microstructures.

Due to the elimination of many optical systems, the price competitiveness of the device is increased, and the optical fiber according to the present invention is used as an optical transmission and processing tool in view of the advantages of improving the quality of the processing part, shortening the processing time, and improving the processing productivity by connecting other optical fiber elements. It is thought that the laser etching apparatus to be used and the processing method thereof can be used as a core element technology or source technology in the industry for manufacturing micro devices using micro holes or channels.

Laser etching technology according to the present invention is applicable to a variety of materials, such as semiconductors or insulators, as well as metals, to enable the development of micro devices and systems of a variety of functions and structures, in particular, high durability micro heat exchanger, generator, reactor It is expected to contribute to the development of such technologies.

In addition, when the processing method according to the present invention is applied, the size of the processing part can be reduced by connecting different optical fiber elements of various types to the middle or the end of the optical fiber, and it is possible to process several structures of the same size at the same time, and thus laser etching It also solves the problem of low productivity, which was one of the disadvantages of machining.

Claims (16)

A laser etching method of irradiating a workpiece in an etching solution with a laser beam to induce a chemical reaction between the workpiece and the etching solution in a portion to which the laser beam is irradiated to smoothly process the workpiece. A laser beam generating step of generating a laser beam; Transmitting a laser beam through the optical fiber for transmitting the generated laser beam toward the workpiece through the optical fiber; A laser beam irradiation step through an optical fiber for irradiating the laser beam by emitting the laser beam transmitted toward the workpiece to a portion to be processed through the optical fiber; And And an optical fiber insertion step of inserting the optical fiber end from which the laser beam is emitted into the processing unit formed in the workpiece by the laser beam irradiation step. delete The laser etching method of claim 1, further comprising a vertical movement step of vertically moving the ends or the workpiece of the optical fiber from which the laser beam is emitted. 2. The method of claim 1, further comprising branching the laser beam into two or more optical fibers. The laser etching method according to claim 1, further comprising a laser beam focusing step of focusing the laser beam emitted from the optical fiber into a lens-type optical fiber. The method of claim 1, wherein the etching solution is circulated in the chamber, the process of processing the workpiece by the laser beam irradiated to the workpiece, and the photographed output to the display. Laser etching method using the optical fiber as a light transmission and processing tool further comprising. A laser etching apparatus for processing a workpiece by irradiating a workpiece in an etching solution contained in a chamber with a laser beam to induce a chemical reaction between the workpiece and the etching solution in a portion to which the laser beam is irradiated. , A laser for generating a laser beam; An optical fiber for receiving the laser beam generated by the laser, transferring the received laser beam toward the workpiece, and emitting the laser beam to a portion to be processed to irradiate the laser beam; It includes a micro-feed system for relatively moving the end of the optical fiber and the workpiece to the laser beam is emitted, The optical fiber end from which the laser beam is emitted is mounted to an optical fiber ferrule which is not corroded to the etching solution, and the microfeed system is a first microfeed system for transferring the end of the optical fiber, and the ferrule is held on the first microfeed system. Laser etching equipment using optical fiber with jig as light transmission and processing tool. delete 10. The method of claim 8, wherein the first microfeeding system is driven by a precision motor, the first microfeeding system is connected to a motor driving device, the motor driving device is connected to a computer in which a control program of the motor driving device is installed optical fiber Laser etching equipment used as a light transmission and processing tool. The optical transmission and processing tool of claim 7, wherein the microfeed system is a second microfeed system for microfeeding the chamber, and the chamber is provided with a pump and a circulation tube for circulating the etching solution in the chamber. Laser Etching Equipment The method of claim 7, wherein one side of the chamber is formed with a transparent portion, the outside of the transparent portion is provided with a camera for photographing the inside of the chamber, the camera is connected to a computer having a display to confirm the processing process Laser etching equipment using the optical fiber as a light transmission and processing tool. The laser etching apparatus according to claim 7, wherein one end of the optical fiber to which the laser beam is incident is provided with an optical fiber provided with a third microtransmission system for adjusting the position of one end of the optical fiber as a light transmission and processing tool. The optical fiber according to claim 7, wherein an optical fiber in which an objective lens for focusing the laser beam generated by the laser and entering the one end of the optical fiber is arranged between the laser and one end of the optical fiber to which the laser beam is incident. Laser etching apparatus. 8. The laser according to claim 7, wherein an optical coupler or a splitter is installed at an end of the optical fiber from which the laser beam is emitted, and the optical coupler or two or more other optical fibers are installed in the optical coupler or splitter. Etching equipment. 8. The laser etching apparatus according to claim 7, wherein an optical fiber provided with a lens-type optical fiber is used as an optical transmission and processing tool at the end of the optical fiber from which the laser beam is emitted. 15. The laser etching apparatus according to claim 14, wherein the other optical fibers are lenticular optical fibers as optical transmission and processing tools.

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