Laser-based microfabrication apparatus and method

Abstract

Provided are a microfabrication apparatus and method using a laser capable of finely fabricating a processing hole. 【Solution means】 The microfabrication apparatus using the laser of the present invention includes a laser beam irradiation unit that irradiates a crystallized object to be processed through which a laser beam passes to form a processing hole, an optical unit that irradiates the shape of the laser beam to locally irradiate the laser beam inside the object to be processed and amorphize the crystallized object to be processed, a laser beam irradiation unit that irradiates the pulse width and pulse energy of the laser beam, and a chemical reaction furnace that chemically removes the processing hole formed in the amorphized region of the object to be processed precipitated in the reaction solution contained therein by a chemical reaction. The processing hole can process a narrow hole in which the ratio of the thickness of the object to be processed to the processing hole diameter is several to tens of thousands of times.

Description

Technical Field

[0001] The present invention relates to a microfabrication apparatus and method, and more particularly, to a microfabrication apparatus and method using a laser to finely fabricate the surface and / or interior of a workpiece.

Background Art

[0002] Generally, as transparent ceramic materials such as glass, quartz, and sapphire have characteristics such as brittleness, chemical resistance, amorphousness, and non-conductivity, the processing methods for microfabrication are very limited. In particular, in the case of a fine shape, only a small number of processing steps such as laser processing using an extreme ultraviolet laser are applied.

[0003] However, even in such laser processing, due to problems such as the occurrence of cracks or an increase in shape error, the development of an effective processing method for ceramic materials is not an easy situation.

[0004] Conventionally, a method has been used in which a laser is irradiated onto a ceramic material to form grooves or cracks, and then the processed portion is etched using a reaction solution for microfabrication.

[0005] For example, in Patent Document 1 below, as a step of using laser wet back etching in glass shape processing, a laser irradiated through a glass as a workpiece heats a metal ion electrolyte located on the back surface of the workpiece to indirectly process the workpiece, and a processing method is disclosed.

[0006] In Patent Document 2 below, in indirect processing of glass using a laser, the irradiation path for irradiating the laser is set in units of points or lines, and the units of points or lines are set to be randomly distributed to prevent the setting of a repetitive irradiation path of a specific pattern, reduce the interaction between the laser and bubbles, and improve the processing accuracy, and the configuration of a glass shape processing apparatus is described.

[0007] Therefore, there is a need to develop technology that can microfabricate transparent ceramic materials such as glass, quartz, and sapphire into desired shapes without damaging them, using lasers and etching methods. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Korean Registered Patent No. 10-1625948 (Published May 31, 2016) [Patent Document 2] Korean Registered Patent No. 10-2382471 (Published April 4, 2022) [Overview of the project] [Problems that the invention aims to solve]

[0009] The object of the present invention is to solve the above-mentioned problems and to provide a laser-based microfabrication apparatus and method that can finely process a workpiece into a desired shape without damaging the workpiece, using a laser beam and a reaction solution that chemically reacts with the workpiece. [Means for solving the problem]

[0010] To achieve the above objective, the laser-based microfabrication apparatus according to the present invention includes: a laser beam irradiation unit that irradiates a crystallized workpiece through which the laser beam passes to form a processing hole; an optical unit that irradiates the shape of the laser beam so as to locally irradiate the inside of the workpiece with the laser beam to make the crystallized workpiece amorphous; a laser beam irradiation unit that irradiates the pulse width and pulse energy of the laser beam; and a chemical reaction furnace that chemically removes the processing hole formed in the amorphous region of the workpiece precipitated in a reaction solution contained inside by a chemical reaction, wherein the processing hole is processed such that the ratio of the diameter of the processing hole to the thickness of the workpiece is several times to tens of thousands of times.

[0011] To achieve the above objective, the laser-based microfabrication method according to the present invention includes the steps of (a) using a laser beam irradiation unit to irradiate a crystallized workpiece through which the laser beam passes to form a processed hole, (b) Using the optical unit, the laser beam is irradiated locally into the workpiece, and the shape of the laser beam is irradiated in such a way that the crystallized workpiece becomes amorphous; (c) A step of irradiating with the laser beam pulse width and pulse energy using a laser beam irradiation unit, (d) The process includes the step of precipitating the workpiece in a chemical reactor containing a reaction solution, and chemically removing the processed holes formed in the amorphous region by a chemical reaction with the reaction solution, wherein the processed holes are processed such that the ratio of the diameter of the processed holes to the thickness of the workpiece is several times to tens of thousands of times. [Effects of the Invention]

[0012] According to the laser-based microfabrication apparatus and method of the present invention, a laser beam having high energy per unit volume and a very short pulse width is irradiated onto a workpiece made of a crystallized material through which the laser beam passes, and the laser beam is absorbed into the workpiece, making the inside of the crystallized workpiece amorphous.

[0013] Furthermore, according to the present invention, by increasing the reaction rate of chemical reactions with reaction solutions such as strongly acidic or strongly basic chemical substances in the amorphous region, processing holes formed in the workpiece can be chemically removed by chemical reaction, and a fine pattern using fine processing holes can be processed.

[0014] Furthermore, according to the present invention, it is possible to process extremely fine three-dimensional shapes within a crystallized workpiece and extremely narrow holes where the ratio of the workpiece's thickness to the diameter of the processed hole is several to tens of thousands of times greater, while minimizing cracks and damage to the workpiece. [Brief explanation of the drawing]

[0015] [Figure 1] It is a configuration diagram of a microfabrication apparatus using a laser according to a preferred embodiment of the present invention. [Figure 2] It is an exemplary diagram in which solid workpieces are classified according to the regularity of the array. [Figure 3] It is a process diagram for explaining step by step a microfabrication method using a laser according to a preferred embodiment of the present invention. [Figure 4] It is a diagram showing a workpiece microfabricated according to a preferred embodiment of the present invention. [Figure 5] It is a diagram showing a workpiece microfabricated according to another embodiment of the present invention. [Figure 6] It is a diagram showing a workpiece microfabricated according to the present invention. [Figure 7] It is a diagram showing a workpiece microfabricated according to the present invention. [Figure 8] It is a diagram showing a workpiece microfabricated according to the present invention.

Mode for Carrying Out the Invention

[0016] Hereinafter, a microfabrication apparatus and method using a laser according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0017] FIG. 1 is a configuration diagram of a microfabrication apparatus using a laser according to a preferred embodiment of the present invention.

[0018] Hereinafter, terms indicating directions such as "left side", "right side", "front", "rear", "upper side" and "lower side" are defined to indicate the respective directions based on the states shown in the respective drawings.

[0019] In the present embodiment, the configuration of a microfabrication apparatus and method using a laser for forming a pattern of a fine shape on the surface and / or inside of a workpiece having a certain area and thickness will be described.

[0020] Furthermore, while this embodiment describes processing workpieces made of transparent ceramic materials such as glass, quartz, and sapphire, it should be noted that the present invention is not limited to this, and can be modified to process workpieces made of various materials such as silicon and metal.

[0021] Although such workpieces are in an amorphous state, in this embodiment, a laser beam is irradiated onto a crystalline workpiece to make it amorphous, and then a fine pattern is processed on the surface and inside of the workpiece. After that, the processed areas are rapidly removed by a chemical reaction using a reaction solution such as a strongly acidic or strongly basic chemical substance.

[0022] In other words, when a laser beam with high energy per unit volume and a very short pulse width is irradiated onto a crystalline material through which the laser beam passes, the surface and / or interior of the material absorb the energy of the laser beam and become amorphous.

[0023] The strong acids and strong bases used as reaction solutions, in crystalline materials, undergo a very slow chemical reaction, resulting in the very slow removal of the processed areas.

[0024] On the other hand, in amorphous materials, the processed area is removed very quickly through chemical reactions with strong acids or strong bases.

[0025] Such differences in reaction rates vary depending on the type and concentration of chemicals used as materials and reaction solutions, as well as the process, but differences in rate can range from several times to tens of thousands of times.

[0026] As a result, the present invention enables the formation of fine patterns in an amorphous state by irradiating a crystallized material with a laser beam, and high-speed microfabrication by a chemical reaction using a reaction solution.

[0027] Furthermore, the present invention makes it possible to machine extremely narrow holes, where the ratio of the thickness of the workpiece to the diameter of the machined hole is several times to tens of thousands of times, while minimizing cracks and damage to the workpiece.

[0028] To this end, the laser-based microfabrication apparatus 10 according to a preferred embodiment of the present invention, as shown in Figure 1, includes a laser beam irradiation unit 20 that irradiates a crystallized workpiece 11 through which the laser beam passes to form a fine pattern using processing holes; an optical unit 30 that irradiates the shape of the laser beam to locally irradiate the inside of the workpiece 11 with the laser beam to make the crystallized workpiece 11 amorphous; a laser beam adjustment unit 40 that adjusts the pulse width and pulse energy of the laser beam; and a chemical reaction furnace 70 that chemically removes the amorphous region of the workpiece 11 precipitated in a reaction solution contained inside, along the processing holes, by a chemical reaction. The apparatus processes the workpiece 11 at a speed several to tens of thousands of times faster than the crystallized workpiece 11, so that the ratio of the thickness of the workpiece 11 to the diameter of the processing holes is several to tens of thousands of times faster.

[0029] In addition, a laser-based microfabrication apparatus 10 according to a preferred embodiment of the present invention further includes a transfer unit 50 that moves the laser beam along the fine pattern to be formed, and a control unit 60 that controls the driving of each device.

[0030] The transfer unit 50 has the function of moving the laser beam output by the optical unit 30 along the shape to be processed.

[0031] For this purpose, the transport unit 50 can be configured to move only the optical unit 30, or to move the laser beam irradiation unit 20, the optical unit 30, and the laser beam adjustment unit 40 as a whole.

[0032] The control unit 60 generates control signals to control the driving of the laser beam irradiation unit 20 and the optical unit 30 so that the shape of the laser beam, the pulse width of the laser beam, and the pulse energy of the laser beam are changed and irradiated based on the processing conditions of the workpiece 11.

[0033] Then, the laser beam adjustment unit 40 can drive the laser beam irradiation unit 20 and the optical unit 30 by the control signal from the control unit 60.

[0034] The workpiece 11 is made of a transparent ceramic material such as glass, quartz, or sapphire. Of course, the workpiece 11 may also be made of silicon or metal.

[0035] For example, Figure 2 is an illustrative diagram showing how solid workpieces are classified according to the regularity of their arrangement.

[0036] Figures 2(a) through (c) show the workpiece in single-crystal, polycrystalline, and amorphous states, respectively.

[0037] The workpiece 11, which is provided as glass, quartz, sapphire, silicon, or a metallic material, usually exists in a single-crystal or polycrystalline state, as shown in Figure 2(a) or (b).

[0038] When a laser beam with high energy per unit volume and a very short pulse width is irradiated onto such a crystallized workpiece 11, the workpiece 11 becomes amorphous, as shown in Figure 2(c).

[0039] Furthermore, the amorphous regions in the workpiece 11 can be removed at a very high speed, for example, several to tens of thousands of times faster than the reaction rate in the crystalline state, by chemical reaction with a reaction solution such as a strongly acidic or strongly basic chemical substance.

[0040] For this purpose, the laser beam irradiation unit 20 can be configured as a laser beam generator that generates a laser beam according to the control signal of the control unit 60.

[0041] The optical unit 30 includes one or more lenses that focus the laser beam generated in the laser beam irradiation unit 21, irradiate it toward the workpiece 11, and adjust the shape of the laser beam.

[0042] Therefore, the laser beam is irradiated onto the crystallized workpiece 11 with high energy per unit volume and a very short pulse width in order to locally amorphous the surface and / or interior of the crystallized workpiece 11 through which the laser beam can penetrate.

[0043] For example, the laser beam is irradiated with a pulse width of approximately 10⁻⁴ seconds to 10⁻¹⁵ seconds and an energy of approximately 10 μJ to 100 μJ / μm³, which does not penetrate the workpiece 11, and can locally amorphousize the inside of the crystallized workpiece 11.

[0044] Alternatively, the laser beam can be used with a pulse width of approximately 10⁻⁴ to 10⁻¹⁸ seconds to locally amorphous the interior of the crystallized workpiece 11.

[0045] In other words, the laser beam's energy per unit volume and pulse width can be adjusted under various conditions such as the material, thickness, and size of the workpiece 11, so as to locally amorphousize the crystallized workpiece 11.

[0046] On the other hand, the control unit 60 can use a laser beam to control the operation of the chemical reactor 70 so as to activate a reaction solution, such as a strongly acidic or strongly basic chemical substance, in the amorphous regions of the workpiece 11 on which the fine pattern has been formed.

[0047] The chemical reactor 70 is provided as a container for the reaction solution and includes one or more ultrasonic transducers (not shown) and heating units (not shown) that are driven by control signals from the control unit 60.

[0048] In other words, the control unit 60 generates a control signal to control the drive of the ultrasonic transducer so as to adjust the period, intensity, and direction of the ultrasonic vibrations generated in the chemical reactor 70 based on the output of the laser beam irradiated by the laser beam irradiation unit 20.

[0049] Here, the ultrasonic vibration is applied in a direction parallel to the direction of the machining hole formed in the workpiece 11. Alternatively, the ultrasonic vibration may be applied in a direction perpendicular to the direction of the machining hole formed in the workpiece 11.

[0050] Furthermore, the control unit 60 generates a control signal to control the drive of the heating unit so that the reaction solution and the object to be heated are heated to a predetermined temperature in order to heat and activate the reaction solution.

[0051] The set temperature is set to correspond to the melting point of the chemical components contained in the reaction solution. The transfer unit 50 moves the irradiation position of the laser beam.

[0052] Of course, the present invention also allows for microfabrication by chemically removing the processing holes formed in the workpiece by spraying the reaction solution onto the workpiece, instead of removing the chemical reaction furnace and precipitating the workpiece in the reaction solution.

[0053] Thus, the present invention irradiates a workpiece made of a crystallized material through which a laser beam passes with a laser beam having high energy per unit volume and a very short pulse width, causing the laser beam to be absorbed into the workpiece and making the inside of the crystallized workpiece amorphous.

[0054] As a result, the present invention increases the reaction rate at which chemical reactions occur with reaction solutions such as strongly acidic or strongly basic chemical substances in the amorphous region, thereby chemically removing processing holes formed in the workpiece through chemical reactions, and enabling the processing of fine patterns using fine processing holes.

[0055] As a result, the present invention makes it possible to process extremely fine three-dimensional shapes inside a crystallized workpiece and extremely narrow holes where the ratio of the workpiece's thickness to the diameter of the processed hole is several to tens of thousands of times greater, while minimizing cracks and damage to the workpiece.

[0056] Next, with reference to Figures 3 to 5, a laser-based microfabrication method according to a preferred embodiment of the present invention will be described in detail.

[0057] Figure 3 is a step-by-step process diagram illustrating a laser-based microfabrication method according to a preferred embodiment of the present invention.

[0058] Furthermore, Figure 4 shows a workpiece that has been micro-machined according to a preferred embodiment of the present invention, and Figure 5 shows a workpiece that has been micro-machined into a three-dimensional shape according to another embodiment of the present invention. Figures 4(a) to 4(c) show the plan view, cross view, and bottom view of the micro-machined workpiece, and Figures 5(a) to 4(c) show the plan view, cross view, and bottom view of the micro-machined workpiece that has been micro-machined into a three-dimensional shape.

[0059] In step S10 of Figure 3, the laser beam irradiation unit 20 generates a laser beam at an output set by the control signal of the control unit 60 and irradiates it toward the workpiece 11. The optical unit 30 then irradiates the workpiece in the shape of the irradiated laser beam.

[0060] Here, the laser beam is a laser beam that has high energy per unit volume and a very short pulse width.

[0061] The irradiated laser beam is then absorbed into the workpiece 11, causing the inside of the workpiece 11 to become amorphous and form an amorphous region (S12).

[0062] In addition, in step S14, the laser beam forms one or more processed holes in the amorphous region, forming a fine pattern.

[0063] The aforementioned processed hole has an extremely fine three-dimensional shape, but it is formed as an extremely narrow hole where the ratio of the diameter of the processed hole to the thickness of the workpiece 11 is several times to tens of thousands of times.

[0064] For example, as shown in Figure 4, the processing hole 12 is formed in a straight line on one surface of the workpiece 11 to be irradiated with the laser beam, for example, on the upper surface, toward the opposite surface, i.e., the lower surface.

[0065] Furthermore, the processed hole 12 is formed not only in a straight line, but also includes one or more right-angled portions 13 or horizontal portions that are formed horizontally so as to be parallel to the surface of the workpiece 11, as shown in Figure 5.

[0066] Furthermore, the processed hole 12 can be formed not only in a straight line perpendicular to the surface of the workpiece 11, but also at an angle predetermined to the surface.

[0067] In this way, the processed holes 12 are formed into various three-dimensional shapes depending on the fine pattern to be created.

[0068] In particular, the processed hole 12 can be formed with a roughly circular cross-section, but depending on the direction in which the ultrasonic vibration is applied, it can be formed with a roughly elliptical cross-section as well as a circular one.

[0069] In the process of forming such fine patterns, the control unit 60 controls the driving of the laser beam irradiation unit 20 and the optical unit 30 so as to change the shape of the laser beam, the pulse width of the laser beam, and the pulse energy of the laser beam based on the processing conditions of the workpiece 11.

[0070] Once the fine pattern formation process is complete, in step S16 the workpiece 11 is deposited in a chemical reactor 70 containing a reaction solution.

[0071] In step S18, the amorphous regions in the workpiece 11 precipitated in the chemical reactor 70 are chemically removed by a chemical reaction with the reaction solution, thereby micro-machining at high speed.

[0072] Here, the ultrasonic transducer installed in the chemical reactor 70 is driven by a control signal from the control unit 60, and can apply ultrasonic vibrations to the workpiece 11 at a predetermined cycle.

[0073] Furthermore, the control unit 60 can control the drive of the ultrasonic transducer to adjust the period, intensity, and direction of the ultrasonic vibrations generated in the chemical reactor 70 based on the output of the laser beam irradiated by the laser beam irradiation unit 20.

[0074] Here, the ultrasonic vibration is applied in a direction parallel to the direction of the machining hole 12 formed in the workpiece 11, or in a direction perpendicular to the direction of the machining hole 12.

[0075] Furthermore, the heating unit installed in the chemical reactor can be driven by a control signal from the control unit to heat the reaction solution and the object to be heated to a predetermined temperature in order to heat and activate the reaction solution.

[0076] To this end, the control unit 60 generates a control signal that controls the operation of the heating unit so that the reaction solution and the object to be heated are heated to a predetermined temperature.

[0077] Furthermore, the set temperature is set to correspond to the melting point of the chemical components contained in the reaction solution.

[0078] Of course, the workpiece 11 is micro-machined by a chemical reaction after a reaction solution is sprayed onto it using a spray nozzle.

[0079] Through the process described above, the present invention irradiates a workpiece made of a crystallized material through which the laser beam passes with a laser beam having high energy per unit volume and a very short pulse width, and the laser beam is absorbed into the workpiece, causing the inside of the crystallized workpiece to become amorphous.

[0080] As a result, the present invention increases the reaction rate at which chemical reactions occur with reaction solutions such as strongly acidic or strongly basic chemical substances in the amorphous region, thereby chemically removing processing holes formed in the workpiece through chemical reactions, and enabling the processing of fine patterns using fine processing holes.

[0081] As a result, the present invention makes it possible to process extremely fine three-dimensional shapes inside a crystallized workpiece and extremely narrow holes where the ratio of the workpiece's thickness to the diameter of the processed hole is several to tens of thousands of times greater, while minimizing cracks and damage to the workpiece.

[0082] [Example 1] The workpiece 11 is quartz with a thickness of approximately 0.1 mm, and the laser beam irradiation unit 20 irradiates it with a picosecond ultraviolet laser beam capable of outputting approximately 100 W.

[0083] The laser beam pulse width was 1 ps, and the laser beam adjustment unit 40 set the overlap rate between laser beams to approximately 50%, so that the laser beam processed the inside of the workpiece 11 with a diameter of approximately 10 μm.

[0084] Furthermore, using a strongly acidic reaction solution such as sulfuric acid (H2SO4) or hydrochloric acid (HCl), only the processed areas, i.e., the processed holes 12 formed in the amorphous regions, were chemically removed.

[0085] As a result, it can be confirmed that the workpiece 11 is finely machined with processing holes 12, as shown in Figures 4(a) to (c).

[0086] [Example 2] The workpiece 11 is a sapphire with a thickness of approximately 1 mm, and the laser beam irradiation unit 20 irradiates it with a femtosecond ultraviolet laser beam capable of outputting approximately 30 W.

[0087] The laser beam pulse width was 10 fs, and the laser beam adjustment unit 40 set the overlap ratio of the laser beams to approximately 80%, so that the laser beam processed the inside of the workpiece 11 with a diameter of approximately 30 μm.

[0088] Furthermore, using strongly basic reaction solutions such as sodium hydroxide (NaOH) or barium hydroxide (Ba(OH)2), only the fine patterns formed by the amorphous regions were chemically removed.

[0089] As a result, it can be confirmed that the workpiece 11 has finely machined holes 12 in which the diameter of the hole is represented in a thickness-to-hole ratio of 30:1.

[0090] [Example 3] The workpiece 11 is a silicon wafer with a thickness of approximately 730 μm, and the laser beam irradiation unit 20 irradiates it with a femtosecond ultraviolet laser beam capable of outputting approximately 30 W.

[0091] The laser beam pulse width was 30 fs, and the laser beam adjustment unit was set to an overlap ratio of approximately 10% between laser beams. The laser beam processed the inside of the workpiece with a diameter of approximately 7 μm.

[0092] Furthermore, by chemically removing only the fine patterns formed in the amorphous region using a strong acid solution, it can be confirmed that the workpiece 11 is finely machined with processed holes 12 that are realized with a thickness-to-hole diameter ratio of 100:1.

[0093] On the other hand, while the above-mentioned embodiment described the process of machining linear micro-holes in a workpiece, the present invention is not limited to this, and can machine not only linear micro-holes but also various three-dimensional micro-patterns.

[0094] As shown in Figure 5, the workpiece 11 is a piece of glass with a width, length, and thickness of approximately 50 mm, and the laser beam irradiation unit 20 irradiates it with a nanosecond laser beam of deep ultraviolet wavelength capable of outputting approximately 10 W.

[0095] Furthermore, the laser beam adjustment unit 40 adjusts the wavelength, pulse width, and beam mode of the laser beam based on the control signals from the control unit 60, and the optical unit 30 adjusts the beam shape of the laser beam.

[0096] For example, the shape of the beam can be changed to various shapes, such as circular or elliptical.

[0097] Furthermore, the beam modes include Gaussian beam modes and non-Caussian beam modes.

[0098] Here, the laser beam was used to pre-treat the workpiece 11 in a caustic beam mode and circular beam shape. Etching was then performed using a strong acid solution of approximately 5% for about 2 hours to chemically remove only the fine patterns formed in the amorphous region.

[0099] This process created a fine pattern using 2304 holes, each with a diameter of approximately 50 μm, arranged in a 48 x 48 pattern with intervals of approximately 0.2 mm along the horizontal and vertical directions. The holes 12 were formed with a diameter ratio of 100:1 to the thickness of the workpiece 11.

[0100] Here, as shown in Figures 5(a) to 5(c), the processed hole 12 can be formed not only in a straight line along the vertical direction, but also to include a right-angle portion 13 along the left-right direction at a certain depth inside the workpiece 11.

[0101] In other words, the present invention allows for the control of the focal length of a laser beam, enabling the movement of the laser beam within the workpiece to process not only linearly along the vertical direction but also horizontally along the left-right direction, creating one or more right-angled holes within the workpiece.

[0102] Furthermore, the present invention makes it possible to form a machining hole that is inclined by a predetermined angle from one side of the workpiece toward the opposite side.

[0103] In other words, the present invention can process various three-dimensional micro-patterns by adjusting the laser beam mode, beam shape, and other parameters along with the depth to which the laser beam is irradiated, thereby processing holes of various diameters and shapes, for example, along the direction of inclination.

[0104] For example, Figures 6 to 8 show a workpiece that has been micro-machined according to the present invention.

[0105] In Figure 6, the workpiece has a thickness of approximately 5 mm, and the processed holes formed in the workpiece have a diameter of approximately 20 μm to 80 μm.

[0106] Figure 7(a) shows a workpiece that has been micro-machined, and Figure 7(b) shows an enlarged cross-sectional view of a pair of machined holes formed in the workpiece.

[0107] In Figures 7(a) and 7(b), the workpiece has a thickness of approximately 2 mm, and the processed holes formed in the workpiece have a diameter of approximately 40 μm.

[0108] Figure 8 is a diagram comparing the workpiece processed by the conventional technology with that processed by the present invention.

[0109] Figure 8(a) shows a cross-section of a workpiece in which a machining hole has been machined using the conventional technology, and Figure 8(b) shows a cross-section of a workpiece in which a machining hole has been machined using the present invention.

[0110] According to the conventional technology, as shown in Figure 8(a), if the reaction solution is not sufficiently introduced into the laser-processed hole 12, the central part of the workpiece 11 is processed to be smaller in diameter than the upper and lower parts, resulting in a roughly mortar-like shape.

[0111] On the other hand, according to the present invention, as shown in Figure 8(b), a laser beam with high energy per unit volume and a very short pulse width is irradiated onto a workpiece 11 made of a crystallized material through which the laser beam passes. The laser beam is absorbed into the workpiece, causing the inside of the crystallized workpiece to become amorphous. By increasing the reaction rate at which the chemical reaction with the reaction solution takes place in the amorphous region, it was confirmed that the processing holes 12 formed in the workpiece 11 are chemically removed by the chemical reaction, resulting in fine processing.

[0112] Thus, the present invention allows for the high-speed processing of various three-dimensional patterns by controlling the focal length, wavelength, pulse width, beam mode, and beam shape of a laser beam to form processing holes of various shapes, and by chemically removing fine patterns through a chemical reaction with an etching solution.

[0113] Furthermore, the present invention makes it possible to process extremely fine three-dimensional shapes within a crystallized workpiece and extremely narrow holes where the ratio of the workpiece's thickness to the diameter of the processed hole is several to tens of thousands of times greater, while minimizing cracks and damage to the workpiece.

[0114] Although the present invention has been specifically described above with reference to the above embodiments, the present invention is not limited to the above embodiments and can be modified in various ways without departing from the spirit of the invention. [Industrial applicability]

[0115] This invention applies to a technique for high-speed microfabrication in which a laser beam is irradiated onto a workpiece made of a crystallized material, the laser beam is absorbed into the workpiece, causing the inside of the crystallized workpiece to become amorphous, and the fine patterns formed in the amorphous region are chemically removed by a chemical reaction. [Explanation of Symbols]

[0116] 10 Microfabrication equipment 11. Object to be processed 12 Machining hole 13 Right-angle section 20 Laser beam irradiation section 30 Optics Department 40 Laser beam adjustment unit 50 Transfer section 60 Control Unit 70 Chemical reactors

Claims

1. A laser beam irradiation unit that irradiates a crystallized workpiece through which the laser beam passes to form a processing hole, An optical unit that adjusts the shape of the laser beam to locally irradiate the inside of the workpiece and make the crystallized workpiece noncrystallized, A laser beam adjustment unit that adjusts the pulse width and pulse energy of the laser beam, A transfer unit that moves the laser beam along a fine pattern, A chemical reaction furnace is equipped with an ultrasonic transducer that applies ultrasonic vibrations to a workpiece at a predetermined period, and which precipitates the workpiece, from which the processing holes have been formed by the laser beam, into a reaction solution and processes the processing holes by a chemical reaction, The system includes a control unit that controls the operation of the laser beam irradiation unit, optical unit, laser beam adjustment unit, transfer unit, and chemical reactor, The workpiece is made of a transparent ceramic material, or a silicon or metallic material. The laser beam is irradiated onto the crystallized workpiece, through which the laser beam can penetrate, with a predetermined energy per unit volume and pulse width. The control unit generates a control signal to irradiate the laser beam with the desired shape, pulse width, and pulse energy based on the processing conditions of the workpiece, controls the wavelength, pulse width, and beam mode of the laser beam, and adjusts the beam shape of the laser beam according to the material and specifications of the workpiece, and further generates a control signal to control the drive of the ultrasonic transducer to adjust the period, intensity, and direction of the ultrasonic vibrations generated in the chemical reactor according to the output of the laser beam irradiated from the laser beam irradiation unit, thereby activating the reaction solution in the amorphous regions of the workpiece. The machining process involves removing machining holes formed in the non-crystallized region of the workpiece by a chemical reaction, so that the ratio of the thickness of the crystallized workpiece to the diameter of the machining holes increases by several to tens of thousands of times. A laser-based micro-machining apparatus characterized in that the processed holes are formed in one or more of the following shapes: a straight line extending from one side of the workpiece irradiated with the laser beam to the opposite side, a shape including one or more right angles, and a shape inclined by a predetermined angle.

2. The laser-based microfabrication apparatus according to claim 1, characterized in that the aforementioned chemical reaction is carried out using a strong acid or a strong base chemical substance.

3. The chemical reactor uses a heating unit to heat the reaction solution and the object to be heated to a predetermined set temperature in order to activate the reaction solution, which is the chemical substance. The laser-based microfabrication apparatus according to claim 2, characterized in that the set temperature is set to correspond to the melting point of the chemical components contained in the reaction solution.

4. (a) Using a laser beam irradiation unit, a laser beam is irradiated onto a crystallized workpiece through which the laser beam passes to form a processing hole; (b) Using the optical unit, the step of adjusting the shape of the laser beam so as to locally irradiate the inside of the workpiece with the laser beam and make the crystallized workpiece amorphous, (c) A step of adjusting the pulse width and pulse energy of the laser beam using a laser beam adjustment unit, (d) A step of equipping the workpiece with an ultrasonic transducer that applies ultrasonic vibrations to the workpiece at a predetermined period, and settling the workpiece in a chemical reaction furnace containing a reaction solution, thereby chemically removing the workpiece holes formed in the amorphous region by a chemical reaction with the reaction solution, (e) The step of moving the laser beam to the pattern in which the processing hole is to be formed using a transfer unit, In the process of performing steps (a) to (e) above, the control unit controls the drive of the laser beam irradiation unit, optical unit and transport unit so as to change the shape of the laser beam, the pulse width and pulse energy of the laser beam based on the processing conditions of the workpiece, and irradiate it. The workpiece is made of a transparent ceramic material, or a silicon or metallic material. The laser beam is irradiated onto the crystallized workpiece, through which the laser beam can penetrate, with a predetermined energy per unit volume and pulse width. In step (c), the control unit controls the laser beam to adjust the wavelength, pulse width, and beam mode, as well as the beam shape of the laser beam, according to the material and specifications of the workpiece. The aforementioned machined hole is processed such that the ratio of the diameter of the machined hole to the thickness of the workpiece is several times to tens of thousands of times. The control unit generates a control signal to control the drive of the ultrasonic transducer in order to adjust the period, intensity, and direction of the ultrasonic vibrations generated in the chemical reactor according to the output of the laser beam irradiated from the laser beam irradiation unit, thereby activating the reaction solution in the amorphous region of the workpiece. A laser microfabrication method characterized in that the processed holes are formed in one or more of the following shapes: a straight line extending from one side of the workpiece irradiated with the laser beam to the opposite side, a shape including one or more right angles, and a shape inclined by a predetermined angle.

5. The laser-based microfabrication method according to claim 4, characterized in that the chemical reaction is carried out using a strong acid or a strong base chemical substance as the reaction solution.

6. The chemical reactor uses a heating unit to heat the reaction solution and the object to be heated to a predetermined set temperature in order to activate the reaction solution. The laser microfabrication method according to claim 5, characterized in that the set temperature is set to correspond to the melting point of the chemical components contained in the reaction solution.

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