KR101010736B1 - Apparatus and method for fabrication of perforated polymer membrane - Google Patents

Abstract

The present invention relates to an apparatus for manufacturing a perforated polymer thin film, comprising: a mold on which a pattern is formed; A rotating part to rotate the mold; Compressor storage unit for storing the compressor body; And a compressor body ejecting unit connected to the compressor body storage unit for injecting the compressor body, wherein a prepolymer is introduced onto the mold and the mold is rotated by the rotating unit so that the prepolymer is a polymer. It is formed as a thin film, characterized in that the compressor body is sprayed on the polymer thin film by the compressor body ejection unit to selectively puncture the polymer thin film.

Description

Apparatus and method for manufacturing a perforated polymer thin film {APPARATUS AND METHOD FOR FABRICATION OF PERFORATED POLYMER MEMBRANE}

 The present invention relates to an apparatus and a method for manufacturing a perforated polymer thin film, and more particularly, to remove the prepolymer remaining on the micro mold by the blowing of compressed gas to selectively produce a perforated polymer membrane (perforated polymer membrane) It relates to a manufacturing apparatus and a manufacturing method.

At present, the development of microfluidic control devices requires complex shapes and fabrication methods to implement various functions in one device. In particular, there have been various research reports that microfluidic devices can implement various functions by flowing along a microfluidic channel designed in three dimensions instead of flowing in one plane. In addition, a method of punching a thin film in a microfluidic control device that depends on a polymer-based manufacturing technology has been used in various fields. Perforation of the polymer thin film has been used for various purposes, such as the fabrication of the three-dimensional microfluidic channel, a microwell for cell culture, and a micropattern transfer method. However, the known methods require complicated manufacturing processes and additional equipment to be widely used in various laboratories.

The invention disclosed in US Pat. No. 7,282,240 is known as the method of perforating a polymer thin film by the simplest method. The patent document discloses a method of preparing a polymer in a thin film form by placing a polymer material (prepolymer) before a polymerization reaction on a mold and applying centrifugal force. In this case, the microstructure is patterned with a material such as a photoresist, so that when the polymer thin film is spin coated to a predetermined height or less, the mold has a principle that the photoresist pattern is perforated. However, when manufacturing thin films of various heights or polymer thin films having various viscosities, thin films are produced at low spin coating speeds. In this case, residual polymer materials remain on the photoresist pattern, so that the perforations are not perforated. There is a problem that a thin polymer film is formed on the portion to be.

The problem to be solved by the present invention is to provide an apparatus and method for producing a polymer thin film that can selectively puncture the polymer thin film by removing the residual polymer on the micro-pattern generated during the production of the perforated polymer thin film.

In order to solve the above problems the apparatus for producing a perforated polymer thin film according to the present invention,

A mold in which a pattern is formed; A rotating part to rotate the mold; Compressor storage unit for storing the compressor body; And a compressor body ejecting unit connected to the compressor body storage unit for injecting the compressor body, wherein a prepolymer is introduced onto the mold and the mold is rotated by the rotating unit so that the prepolymer is a polymer. It is formed as a thin film, characterized in that the compressor body is sprayed on the polymer thin film by the compressor body ejection unit to selectively puncture the polymer thin film.

Here, it is preferable to selectively perforate the polymer thin film by spraying and removing the compressor body on the prepolymer remaining on the pattern.

Moreover, it is preferable that the said rotating part and the said mold adhere to each other by pressure reduction.

In addition, the thickness of the polymer thin film is preferably adjusted according to the rotational speed of the rotating unit.

In addition, the compressor body ejection unit may be provided in plural, and the compressor body may be simultaneously injected to a plurality of positions.

In addition, a jet port is provided at one end of the compressed gas ejection unit, and the compressed air ejection unit is detachably connected to the compressed gas storage unit so that the size of the ejection port depends on the viscosity of the prepolymer or the size of the hole to be drilled. Can be changed.

In addition, the prepolymer is any one selected from the group consisting of polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polyacrylate, polycarbonylate, polycyclic olefin, polyimide, polyurethane It is preferable that it is above.

In addition, the pattern is preferably made of a first pattern portion protruding from the mold.

In addition, the pattern is preferably made of a first pattern portion protruding from the mold and a second pattern portion protruding from the first pattern portion.

Method for producing a perforated polymer thin film according to the present invention to solve the above problems,

Placing a patterned mold on a rotating part; A second step of injecting a prepolymer onto the mold in close contact with the rotating part by pressure reduction; A third step of rotating the rotating unit to form the prepolymer into a polymer thin film; A fourth step of selectively removing the prepolymer remaining on the pattern by the injection force of the compressor body; And a fifth step of polymerizing the polymer thin film and removing the polymerized polymer thin film from the mold.

Here, between the fourth step and the fifth step, the step of leaving the prepolymer to recover the prepolymer damaged by the injection force of the compressor body; preferably further comprises a.

In addition, the polymerized polymer thin film may be cured by polymerizing the polymer thin film.

In addition, the prepolymer is any one selected from the group consisting of polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polyacrylate, polycarbonylate, polycyclic olefin, polyimide, and polyurethane It is preferable that it is above.

As described above, the apparatus and method for manufacturing a selectively perforated polymer thin film according to the present invention should be perforated on a mold according to physical properties such as the thickness and viscosity of a specific polymer thin film in the conventional spin coating-only manufacturing method. The process problems caused by the prepolymer remaining on the pattern of the part can be solved using a compressor body injection technique, enabling the selective drilling of the desired position.

In addition, in order to perform selective drilling in the conventional method, since the mold pattern of the portion to be punched must be higher than the portion not to be punched, mold patterns having different heights that can be manufactured by a two-step lithography method or the like are produced. Although it is possible to do this, the manufacturing apparatus and manufacturing method according to the present invention provides the advantage of selectively perforating the polymer thin film even in the mold pattern manufactured using a general single step lithography method.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment according to the present invention, but the present invention is not limited thereto. In addition, the terms or words used in the present specification and claims are consistent with the technical spirit of the present invention on the basis of the principle that the inventor can appropriately define the concept of the term in order to explain the invention in the best way. It must be interpreted as meaning and concept.

1 is a view schematically showing an apparatus for manufacturing a perforated polymer thin film according to the present invention. The apparatus for producing a perforated polymer thin film of the present invention includes a mold 104 in which a pattern is formed, a rotating part (spin coater) 105 for rotating the mold, a compressor body storage unit 101 for storing a compressor body, and And a compressed gas ejection unit 102 for injecting compressed gas.

As shown in FIG. 1, the prepolymer is formed into the polymer thin film 103 by inserting a prepolymer onto the mold 104 and rotating the mold 104 using the rotating part 105. do. At this time, the rotating part 105 and the mold 104 are in close contact with each other by decompression. In addition, the thickness of the polymer thin film 103 formed by the centrifugal force by the rotating unit 105 may be controlled by controlling the rotational speed of the rotating unit. In the case where the residual prepolymer remains in the position to be punctured, the polymer thin film in the desired position is selectively removed by spraying the compressor body stored in the compressor body storage unit 101 through the compressor body ejection unit 102 to remove the residual prepolymer. Can be drilled. Thereafter, the polymer thin film perforated through the polymerization is cured to remove it from the mold 104, thereby obtaining a finally punched polymer thin film.

On the other hand, when the compressor body is sprayed on the polymer thin film 103 obtained by rotating the prepolymer on the mold 104 using the compressor body ejection unit 102, the residual prepolymer is removed and at the same time, the polymer thin film 103 has a partial defect. This will occur. However, since such defect sites are spontaneously restored as time passes, the polymerized polymerization reaction may be completed after the polymer polymerization reaction is left for 30 minutes or more. The shape of the hole formed in the finally produced polymer thin film coincides with the patterned shape in the mold 104, and may have various shapes such as a circular rectangle.

A method of manufacturing the perforated polymer thin film according to the present invention will be described with reference to FIG. Referring to FIG. 2, in the method of manufacturing the perforated polymer thin film of the present invention, first, a predetermined amount of prepolymer 201 is poured into a mold 104 in which a pattern 106 is formed. The polymer thin film 202 having a predetermined thickness is formed on the mold by the centrifugal force of spin coating. However, because the residual prepolymer 203 is present on the pattern 106 of the mold, it is impossible to fabricate a fully perforated polymer thin film. Therefore, the residual prepolymer is removed by using the injection force of the compressed gas injected through the jet port 102a formed at one end of the compressed air jet part. In this case, one or more compressor body ejection units may be provided, through which the compressor body may be simultaneously injected into one or a plurality of positions. In addition, it is preferable that the injection force of the compressor body is changed according to the viscosity of the prepolymer or the size to be punctured. Can change.

On the other hand, the damaged portion 204 of the surrounding polymer thin film accompanying the removal is spontaneously recovered over time. When the polymer thin film made of the prepolymer whose shape has been restored is polymerized by thermal or optical methods, and the cured polymer thin film 205 is removed from the mold, the polymer thin film can be selectively manufactured. At this time, the pattern of the mold to be used is composed of the first pattern portion 106a protruding from the mold 104 and the second pattern portion 106b protruding from the first pattern portion 106a, so that only the portion to be punched has a high pattern. The fabricated multi-step lithography (FIG. 2, A) method and the one-step lithography (FIG. 2, B) method in which the pattern is manufactured so that the height of the first pattern portion 106a are all used are used. Can be.

Hereinafter, a method of fabricating a selectively perforated polymer thin film using a mold fabricated using a multi- or single-stage lithography method will be described with reference to examples. However, the following examples are intended to illustrate the present invention as an embodiment of the present invention, the content of the present invention is not limited by the examples.

Example 1 Mold Fabrication and Perforated Polydimethylsiloxane (PDMS) Thin Film Fabrication Using Multi-Step Lithography Method (FIG. 2, A)

Molds used in the examples of the present invention were fabricated by patterning onto silicon wafers using SU-8 photoresist. The height of the photoresist consisted of patterns having different heights of 20 μm and 50 μm, and the 50 μm pattern was designed to be perforated. The mold is placed on a spin coater and fixed through a decompression device, and the PDMS (mixture of a prepolymer and a curing agent in a mixture of 10: 1) before polymerization is poured onto the wafer. Spin coating at 3000 rpm for 30 seconds forms a thin film of PDMS prepolymer about 45 μm to 50 μm high on the wafer. A 30 gauge syringe needle was used for the compressed gas ejection part connected to the air compressor to remove the PDMS prepolymer remaining on the 50 μm high pattern to produce a perfect perforation. The syringe needles of different gauges may be connected to the air compressor to change the blowing force of the compressed air, and the plurality of syringe needles may be connected together to the air compressor to simultaneously spray the compressor body at various positions. The polymer material remaining on the 50 μm pattern was removed by using the injection force of the compressed gas injected from the 30 gauge needle. If left at room temperature for 30 minutes to recover the polymer thin film formed of the prepolymer damaged form by gas injection, it will return to its original shape leaving only the part to be spun spontaneously. For polymerization, the cured PDMS thin film was prepared by curing at 60 ° C. for 2 hours. Photographs of the prepared PDMS thin film were observed with a scanning electron microscope (SEM) and are shown in FIG. 3. Reference numeral “301” in FIG. 3 denotes a photoresist pattern patterned by multistage lithography, and reference numeral “302” denotes a portion of the photoresist pattern which is patterned by multistage lithography and used as a connection of a three-dimensional microfluidic channel. Reference numeral "303" denotes a polymer thin film formed by spin coating, reference numeral "305" denotes a perforated hole in the PDMS thin film obtained after removing the residual prepolymer using a compressor body, and reference numeral "306" denotes The electron microscope photograph which enlarged the produced hole is shown. As shown by the reference numeral “304” of FIG. 3, no holes could be observed in the PDMS thin film that was only spin-coated without the process of spraying the compressor.

Example 2 Mold Fabrication and Perforated PDMS Thin Film Fabrication Using Single-Step Lithography Method (FIG. 2, B)

The mold used in the embodiment of the present invention was fabricated by patterning on a silicon wafer using SU-8 photoresist (PR). The height of the photoresist consisted of a pattern having a uniform height of 50 μm, and optionally perforations were made in the pattern at the desired position. The mold is placed on a spin coater and fixed through a decompression device, and the PDMS (mixture of a prepolymer and a curing agent mixed with a 10: 1) material before polymerization is poured onto the wafer. Spin coating at 3000 rpm for 30 seconds forms a thin film of PDMS prepolymer about 45 μm to 50 μm high on the wafer. A 30 gauge syringe needle was used for the compressed gas ejection connected to the air compressor to remove the PDMS prepolymer remaining on the 50 μm high pattern to produce a perfect perforation. The polymeric material remaining on the 50 μm pattern was selectively removed using the blowing force of the compressed gas injected from the 30 gauge needle. If left at room temperature for 30 minutes to recover the polymer thin film formed of the prepolymer damaged form by gas injection, the spontaneous recovery is restored to its original shape, leaving only the portion to be spun spontaneously. For polymerization, the cured PDMS thin film was prepared by curing at 60 ° C. for 2 hours. Photographs of the prepared PDMS thin film were observed with a scanning electron microscope (SEM) and are shown in FIG. 4. In FIG. 4, reference numeral 401 denotes an electron micrograph of a polymer thin film which has not been removed after spin coating of PDMS on a mold prepared by single-stage lithography, and reference numeral 402 denotes an electron micrograph of the polymer prepared by single-stage lithography. After spin coating of PDMS, residual material was selectively removed using a compressive body to show electron micrographs of the PDMS thin films having holes. As shown by the reference numeral 401 in FIG. 4, no holes could be observed in the PDMS thin film that was only spin-coated without the process of spraying the compressor.

As the prepolymers used in Examples 1 and 2 described above, polydimethylsiloxane (PDMS) was used as an example, but polydimethylsiloxane (PDMS), polymethylmethacrylate (PMMA), polyacrylate, It can be any one or more materials selected from the group consisting of polycarbonylates, polycyclic olefins, polyimides, and polyurethanes.

Example 3 Fabrication of 3D Microfluidic Control Device Using Perforated PDMS Thin Film and Implementation Method of 16-Parallel Concentration Gradient Using the Same

In general, a microfluidic control device using PDMS has a structure in which fluid flows through microfluidic channels in the same plane. However, in recent years, microfluidic channels have been used to implement various functions through a three-dimensional three-dimensional structure, in accordance with the demand for more complicated and sophisticated microfluidic devices. In this case, the most important technique for manufacturing a 3D microfluidic channel is a connection part connecting the lower and upper microfluidic channels. These connections are usually made by drilling small holes in PDMS membranes, and various techniques have been used to make holes for the connections of microfluidic channels. In Example 3, a three-dimensional microfluidic channel structure was formed by drilling a PDMS thin film using a method of manufacturing a polymer thin film perforated by the present invention, and two fluids injected into two inlets were three-dimensional microfluidic channel. Shows the results of forming 16 parallel concentration gradients while passing through. The designed and fabricated three-dimensional microfluidic control device is shown in FIG. As shown in FIG. 5 (a), the lower microfluidic channel is connected to the fluid flowing through the upper microfluidic channel through the through hole, and the through hole serving as the connection part uses the SU-8 photoresist pattern of FIG. 5 (b). It produced using the mold which has. The photograph of the completed PDMS microfluidic control element is shown in FIG. 5 (C), and the photograph of the observation of the connection part by the perforation enlarged is shown in FIG. Two injection ports (inlet A, inlet B) of the PDMS fluid control device thus manufactured were injected with food coloring (red dye) on one side and fluorescent material (FITC, Fluorescein isothiocyanate, 3.0 mM) on the other side. As a result, as shown in FIG. 6, the concentration gradient of the microfluid is formed at each microfluidic channel part, and finally, the concentration gradient is formed in parallel in the discharge part. The result of measuring the concentration is shown in FIG.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary and should be understood by those skilled in the art that various modifications and variations of the embodiments are possible therefrom. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown not in the above description but in the claims, and all differences within the equivalent scope will be construed as being included in the present invention.

1 is a conceptual diagram of an apparatus for manufacturing a perforated polymer thin film according to the present invention.

2 is a view illustrating a step-by-step method for manufacturing a perforated polymer thin film according to the present invention.

Figure 3 compares the results of the electron micrograph of the perforated PDMS polymer thin film prepared using a mold prepared by a multi-stage lithography process using the method for producing a perforated polymer thin film according to the present invention, and the result of not removing the residual prepolymer One picture.

FIG. 4 is an electron micrograph of a perforated PDMS polymer thin film prepared using a mold prepared by a single-stage lithography process using the method for preparing a perforated polymer thin film according to the present invention, and a residual prepolymer is removed using a compressor body. It is a photograph comparing the result which did not.

FIG. 5 is a schematic diagram of a design for manufacturing a three-dimensional microfluidic control device using the method for manufacturing a perforated polymer thin film according to the present invention (FIG. 5, (a)), and an electron micrograph (b) of a mold having a pattern. Optical micrograph (C) of the manufactured PDMS 3D microfluidic control device.

6 is a fluorescence micrograph of observing concentration gradients formed by two fluids injected using a three-dimensional PDMS microfluidic control device manufactured by the method of manufacturing a perforated polymer thin film according to the present invention.

FIG. 7 is a graph measuring the concentration gradient shown in FIG. 6.

<Explanation of symbols for the main parts of the drawings>

101: compressor body storage

102: compressed gas jet unit 102a: jet port

103: polymer thin film

104: Mold

105: rotating part

106: pattern 106a: first pattern portion 106b: second pattern portion

201: prepolymer

202: polymer thin film formed through spin coating

203: residual prepolymer

204: damaged portion of the polymer thin film

205: polymer thin film cured through polymerization

301: Patterned photoresist by multistep lithography

302: portion of the photoresist pattern that is patterned by multi-stage lithography and to be used as a junction of three-dimensional microfluidic channels

303: polymer thin film formed by spin coating

304: PDMS thin film with only spin coating without residual prepolymer removal

305: Perforations in the PDMS thin film obtained after removing residual prepolymer using a compressor body

306: Magnified electron micrograph of the manufactured hole.

401: Electron micrograph of polymer thin film without residual material after spin coating of PDMS on mold prepared by single-stage lithography

402: Electron micrograph of a PDMS thin film with a hole formed by spin coating of PDMS on a mold prepared by single-stage lithography, followed by selective removal of residual material using a compact.

Claims (13)

A mold in which a pattern is formed; A rotating part to rotate the mold; Compressor storage unit for storing the compressor body; And And a compressor body ejecting unit connected to the compressor body storage unit and spraying the compressor body. A prepolymer is introduced onto the mold and the mold is rotated by the rotating part to form the prepolymer into a polymer thin film, Apparatus for producing a perforated polymer thin film, characterized in that the compressor body is injected into the polymer thin film by the compressor body ejection to selectively puncture the polymer thin film. The method of claim 1, And selectively perforating the polymer thin film by spraying and removing the compressor body on the prepolymer remaining on the pattern. The method of claim 1, And the rotating part and the mold are in close contact with each other by decompression. The method of claim 1, The thickness of the polymer thin film is a device for manufacturing a perforated polymer thin film, characterized in that it is adjusted according to the rotational speed of the rotating unit. The method of claim 1, Apparatus for producing a perforated polymer thin film, characterized in that the plurality of compressor body ejection unit is provided, the compressor body is sprayed simultaneously to a plurality of positions. 6. The method according to claim 1 or 5, A jet port is provided at one end of the compressed gas jet part, The compressor body ejection unit is detachably connected to the compressor body storage unit, the apparatus for producing a perforated polymer thin film, characterized in that the size of the jet port is changed according to the viscosity of the prepolymer or the size of the hole to be punched. The method of claim 1, The prepolymer is at least one selected from the group consisting of polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polyacrylate, polycarbonylate, polycyclic olefin, polyimide, polyurethane Apparatus for producing a perforated polymer thin film characterized in that. The method of claim 1, The pattern is a device for manufacturing a perforated polymer thin film, characterized in that consisting of a first pattern portion protruding from the mold. The method of claim 1, And the pattern comprises a first pattern portion protruding from the mold and a second pattern portion protruding from the first pattern portion. Placing a patterned mold on a rotating part; A second step of injecting a prepolymer onto the mold in close contact with the rotating part by pressure reduction; A third step of rotating the rotating unit to form the prepolymer into a polymer thin film; A fourth step of selectively removing the prepolymer remaining on the pattern by the injection force of the compressor body; And a fifth step of polymerizing the polymer thin film and removing the polymerized polymer thin film from the mold. The method of claim 10, Between the fourth step and the fifth step, leaving the prepolymer to recover the prepolymer damaged by the injection force of the compressor body; The method of producing a perforated polymer thin film further comprising. The method of claim 10, And polymerizing the polymer thin film to cure the polymerized polymer thin film. The method of claim 10, The prepolymer is at least one selected from the group consisting of polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polyacrylate, polycarbonylate, polycyclic olefin, polyimide, and polyurethane Method for producing a perforated polymer thin film characterized in that.

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