JP2005049334A - Method of manufacturing carbon nanotube array, using self-aggregation of organic supermolecule and staining of metal compound, and biochip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a CNT array manufacturing method for immobilizing a CNT onto a metal catalyst nano-pattern formed using self-aggregation of an organic supermolecule and staining of a metal compound. <P>SOLUTION: This CNT nano-array manufacturing method includes (a) a step for forming a thin film of a metal catalyst selected from Fe, Ni, Co and alloy of the metals, on a substrate, (b) a step for forming the organic supermolecule inducing the self-aggregation on the metal catalyst thin film, (c) a step for self-aggregating the organic supermolecule by annealing to form regular structure, (d) a step for staining the regular structure with the metal compound, (e) a step for removing a portion not stained with the metal compound, using the thin film as a mask, to form a nano-pattern of the organic supermolecule, (f) a step for forming the nano-pattern of the organic supermolecule through ion milling using the nano-pattern as a mask, and (g) a step for arraying the CNT vertical-directionally on the nano-pattern. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

In the present invention, after forming an organic supramolecular thin film on a substrate, self-assembly of the organic supramolecule is induced by annealing, and a metal compound is selectively stained in a certain pattern formed thereby, and then etched. A nanometer or smaller pattern, and carbon nanotubes (CNTs) are grown in the vertical direction, and a bioreceptor is bonded to the fabricated CNT array. It is related with the manufacturing method of the biochip characterized by making it do.

Conventionally, surface pattern formation has mainly been performed by photolithography using a polymer thin film as a photoresist. In order to realize a nanometer-sized high-precision pattern by such a method, usable light can be used. As a problem, there are many difficulties, such as securing the wavelength and the device and technology corresponding to it, and the resolution limit of the polymer itself.

Since 1990, there has been an attempt to increase the resolution of a pattern using light having a shorter wavelength in accordance with an attempt to use a new photosensitive resistor from the existing optical transfer method. A completely new concept of patterning technology, that is, surface nano-patterning technology using soft lithography, has begun to appear. This method has an advantage that a pattern can be formed quickly and inexpensively, and continuous operation is possible. However, the resolution limit is practically 100 nm, and the resolution for further high integration. The increase is likely to be expected.

On the other hand, in the method for forming a nano-scale fine pattern (KR10-0263671B1) of a semiconductor device using organic supramolecules as a material for forming a pattern, a buffer layer is further used to secure an excessive margin for etching. This technique uses spacers in the buffer layer to ensure the thickness of the fine pattern remaining in the buffer and reduce the size of the groove, but it requires many man-hours and the pattern size is on the order of tens of nanometers. .

A recently disclosed self-assembled structure (KR2002-0089528A) relates to a small-sized structure forming a device widely used in the microelectronic industry, and the self-assembled method disclosed in the present invention is a surface Provides the ability to form an array with the self-assembly itself, but the position of the device formation cannot be determined within the boundary along the surface. Thus, although individual positioning techniques are required to form elements within the boundary along the surface, appropriate positioning techniques are used in conjunction with self-assembling methods to generally provide discrete components within an integrated electronic circuit. Forming a structure that can serve as The positioning method can use lithography, direct formation methods, or other positioning techniques to delimit the structure, so that a patterned substrate is formed and devices are assembled on the substrate by self-assembly.

Self-assembled structures can be combined with structures formed by conventional chemical vapor deposition and physical vapor deposition techniques, and integrated electronic circuits can include integrated optical components. The self-assembled structure can be formed using a dispersion of nanoparticles by adjusting the surface of the material, conditions, temperature, and concentration conditions so as to obtain a desired structure formation product. A linker can be used in which one end is chemically bonded to the surface of the substrate and the other end is chemically bonded to the nanoparticles, and selective bonding using the linker can be used to proceed to the self-assembly process.

Another alternative is to use natural interactions such as electrostatic and chemical interactions to proceed through the self-assembly process, where the nanoparticles are within the boundaries defined by the porous region. Are stacked in small holes so as to determine the position of the nanoparticles. Small holes may be found in certain materials such as inorganic oxides or two-dimensional organic crystals, and appropriate holes may be formed, for example, by ion milling or chemical etching. However, the process is complicated, and the pattern spacing remains at the level of several tens to several hundreds of nanometers.

In addition, a nanometer-level high-precision pattern forming method (KR2003-0023191A) using a self-assembled monolayer is known, and the invention discloses an aromatic imine molecule layer having a substituted terminal ring on a substrate. Forming a pattern within a short time, including the step of selectively bonding and cleaving the substituent of the aromatic imine molecule layer and hydrolyzing the aromatic imine molecule layer in which the substituent is selectively cleaved. Provides a method of forming the same, but this also remains at the level of several tens of nanometers.

On the other hand, a dip pen that attaches a surface active molecule having a chemical affinity with a solid substrate to the tip of an atomic force microscope tip, and forms a nano-level pattern on the substrate with the tip of the tip like writing ink on paper. The nanolithography method (Piner, RD et al., Science, 283: 661, 1999) has the advantage that high-resolution nanopatterns down to the 5 nm level can be obtained by using a very elaborate chip. However, since it is necessary to draw patterns one by one continuously, there is a problem that it takes a long time to obtain a desired design. There is.

As described above, various methods such as etching using photolithography, ultraviolet rays, and X-ray have been introduced. However, pattern formation of 100 nm or less will reach its limit, and the existing top method is to solve this. Research on the bottom-up method instead of the down method has been widely conducted.

The bottom-up method is based on the fact that molecules form a fine structure by self-assembly. However, a method of analyzing the fine structure of organic supramolecules with a scanning electron microscope using such basic technology (Hudson, SD et al. Science, 278: 449, 1997) and a paper (Jung, HT et al., Macromolecules, 35: 3717, 2002) that confirms that the orientation of organic supramolecules varies depending on the nature of the substrate surface. However, they are disclosed only for the fine structure analysis of organic supramolecules and the orientation of organic supramolecules, respectively.

Further, a method of forming a regular pattern using a block copolymer and a method of forming a pattern of dots by staining a metal compound (Park, M. et al., Science, 276: 1401, 1997) Although research on making a pattern of 100 nm or less using a block copolymer has been progressing, it is due to the molecular chain of the polymer, and it is the actual situation that the pattern formation of several tens of nanometers or more remains. Further, when the block copolymer is used, there are problems that the aspect ratio of the formed pattern is not large, the structure of the thin film is complicated, and the directionality of the structure of the thin film is difficult to provide.

On the other hand, microarray protein chips currently dominate much of the research on diagnostic proteomics. When arraying polypeptides on the surface of a substrate, the initial array technology (US Pat. No. 5,143,854) that used photolithography technology has recently been tried in various ways. In particular, the importance of developing a microarray type format is gradually increasing in various immunoassays including a pair of antigen / antibody and enzyme-linked immunoreaction adsorption assay.

However, protein arrays are difficult to integrate or array in a substantial format that makes them smaller or more sensitive than DNA arrays. That is, the lattice pattern of a DNA oligonucleotide can be generated on the surface of a substrate by photolithography, but in the case of a protein composed of several hundred amino acids, an antibody generally has about 1400 amino acids. There is a need for more highly integrated and dense lattice patterns on the surface for accurate diagnosis of the disease, but this is not easy to succeed.

Another problem is that when a protein is handled under a denatured state it can easily lose its tertiary structure (Bernard, A. et al., Anal. Chem., 73: 8). 2001), with many limitations when manipulating proteins.

The solution to these problems depends on how high the protein is arranged without losing the tertiary structure of the protein, but so far, inkjet printing, drop-on-demand technology, microcontact printing, and IBM Various approaches such as soft lithography selected by the company have been tried. However, these methods similarly have a spacing size of several tens of μm to several mm, and are highly integrated diagnostic proteins having high density of actual samples without losing the tertiary structure of the protein. Development of nanoarrays has not been attempted.

CNT is excellent in mechanical strength and chemical safety, has properties of semiconductor and conductor, has a short diameter and a relatively long length, flat display element, transistor, energy storage The applicability to body materials and nano-sized sensors is extremely high.

As a method for synthesizing CNTs using a well-known CVD synthesis method, Fe, Ni, Co or an alloy of the metal catalyst is first deposited on a substrate as a metal catalyst, and then the substrate on which the metal catalyst is deposited is washed with water. After etching with HF diluted with, this sample is put on a quartz boat, this quartz boat is put in a reactor of a CVD apparatus, and this metal catalyst film is additionally etched using NH ₃ gas at a temperature of 750 to 1050 ° C. Thus, nano-sized fine metal catalyst particles are formed. Since CNT is synthesized on the fine metal catalyst particles by the CVD synthesis method, the formation of the fine metal catalyst particles is the most important process. However, in such a process, it is impossible to arrange the metal catalyst in a pattern that is patterned at regular intervals. In order to align CNTs vertically at regular intervals, it is very important to array metal catalysts.

  In order to solve the above problems, there has been a report (Li, J. et al., Nano Lett., 3: 597, 2003) in which a nickel catalyst array is made using electron beam lithography to grow CNTs. . However, such a method has many limitations when applied to a substrate having a large area, and there are many problems in mass production.

Recently, research has been conducted to detect a reaction between a protein-protein and a protein-ligand using an electrochemical change of the CNT after immobilizing a biomaterial on the CNT (Dai, H. et al. , ACC.Chem.Res., 35: 1035-44, 2002; Sotilopoulou, S. et al., Anal.Bioanal.Chem., 375: 103-5, 2003; Eranger, BF et al., Nano Lett., 1: 465-7, 2001; Azamian, BR et al., JACS, 124: 12664-5, 2002).

The reason why CNTs are attracting attention as biochips is that, firstly, labeling is not necessary, secondly, they are very sensitive to changes in electrical or electrochemical signals, and third, they are chemically active. This is because it has a group and can be reacted on an aqueous solution without deformation of the protein. The application of biological systems to CNT, a new well-arranged nanomaterial, will create important application technologies in the field of disease diagnosis (genetic diseases), proteomics and nanobiotechnology.

On the other hand, there have been many recent cases where CNT is applied in the field of biotechnology. Glucose sensor, protein detection, specific DNA sequence detection (Sotilopoulou, S. et al., Anal. Bioana. Chem., 375: 103-5, 2003; Chen, RJ et al., Proc. Natl. Acad.Sci.USA, 100: 4984-9, 2003; Cai, H. et al., Anal.Bioanal.Chem., 375: 287-93, 2003), etc. ing. Biomolecule detection from multi-layers based on CNTs has a large surface area and excellent electrical conductivity, the amount of biomolecules such as DNA immobilized increases, and detection sensitivity to biomolecules can be increased.

Currently, the most universal method for detecting reaction results from a biochip is a method using an existing fluorescent substance and an isotope (Toriba, A. et al., Biomed. Chromatogr., 17: 126-). 32, 2003; Syrzycka, M. et al., Anal.Chim.Acta, 484: 1-14, 2003; Rose, JH et al., Nano Lett., 3:59, 2003), easier. New methods that can accurately measure electrical or electrochemical signals have been tried, thereby further increasing the need for a new material called CNTs.

A method of detecting a DNA that binds complementarily after making a high-density CNT multilayer and immobilizing the DNA thereon is useful for genome analysis, mutation detection, pathogen identification, and the like. There are reports that PNA (peptide nucleic acid: DNA analogue) is fixed to single-walled CNTs in a position-specific manner and detected to bind complementarily to the probe DNA (Williams, KA et al., Nature, 420: 761, 2001). There are also examples in which oligonucleotides are immobilized on a CNT array using a chemical method, and DNA is detected using a guanine oxidation method (Li, J. et al., Nano Lett., 3: 597-602, 2003). However, these do not apply CNT to the production and development of biochips.

Recently, a high-dose biomolecule detection sensor (WO 03/016901 A1) using CNT is known. It relates to a multichannel biochip obtained by arranging multiple CNTs using chemical conjugates on the temperament and combining various types of receptors, but it is relatively weak to changes in the surrounding environment There is.

Therefore, as a result of diligent efforts to develop an ultra-high-density pattern forming method having a simpler process and a pattern size of a few nanometers, the present inventors have conducted self-assembly of organic supramolecules and metal compounds. A metal catalyst pattern having a size of several nanometers or less was formed using selective staining, and CNTs were grown in the vertical direction to produce a CNT array, thereby completing the present invention.
KR10-0263671B1 KR10-2002-0089528A KR10-2003-0023191A US5, 143, 854 A 1 WO 03/016901 A1 KR2002-0001260A KR2003-0014997A Piner, R.A. D. et al. Science, 283: 661, 1999. Hudson, S.M. D. et al. Science 278: 449, 1997. Jung, H.C. T.A. et al. , Macromolecules, 35: 3717, 2002. Park, M.M. et al. Science, 276: 1401, 1997. Bernard, A.M. et al. Anal. Chem. 73: 8, 2001. Huang, S.H. et al. J. et al. Phys. Chem. B, 106: 3543, 2002. Dai, H .; et al. ACC. Chem. Res. , 35: 1035, 2002 Sotiropoulou, S .; et al. Anal. Bioanal. Chem. 375: 103, 2003 Erlanger, B.M. F. et al. Nano Lett. 1: 465, 2001 Azamian, B.M. R. et al. , JACS, 124: 12664, 2002. Taton, T. A. et al. Science, 289: 1757, 2000. Cai, H.C. et al. Anal. Bioanal. Chem. 375: 287, 2003 Chen, R.A. J. et al. et al. Proc. Natl. Acad. Sci. USA, 100: 4984, 2003. Toriba, A .; et al. Biomed. Chromatogr. 17: 126, 2003. Syrzycka, M.M. et al. Anal. Chim. Acta, 484: 1, 2003 Rose, J.M. H. et al. Nano Lett. 3:59, 2003 Williams, K.M. A. et al. , Nature, 420: 761, 2001. Li, J.M. et al. Nano Lett. 3: 597, 2003

An object of the present invention is to provide a method of manufacturing a CNT array in which CNTs are fixed to a metal catalyst nanopattern formed by using organic supramolecular self-assembly and selective staining of a metal compound.

Another object of the present invention is to provide a method for manufacturing a biochip, characterized in that a bioreceptor that binds to a biomaterial is attached to the manufactured CNT array.

In order to achieve the above object, the present invention comprises (a) forming a metal catalyst thin film selected from the group consisting of Fe, Ni, Co, and an alloy of the metal on a substrate; (b) the metal catalyst Forming an organic supramolecular thin film that induces self-assembly on the thin film; (c) self-assembling the organic supramolecule by annealing to form a regular structure; (d) self-assembling of the organic supramolecule. (E) a portion in which the metal compound is not stained through etching using the thin film in which the metal compound is selectively stained as a mask; Forming a nano pattern of organic supramolecules in which a metal compound is stained; (f) nano patterns of organic supramolecules in which the metal compound is stained; Provides a method of fabricating a CNT nanoarray comprising the step of arranging the CNT vertically nano pattern and (g) said metal catalyst; a down step to form a nano-pattern of the metal catalyst through ion milling as a mask.

According to one embodiment of the present invention, the organic supramolecule is a compound of the following chemical formula 1, but any organic supramolecule that self-assembles can be used without limitation.

Examples of organic supermolecules that self-assemble include a disk-type or disk-type dendrimer 1, a fan-shaped organic supermolecule 2, a rod-like chain-type or cone-type molecule 5. An example of a fan-shaped organic supramolecule is a compound of the following chemical formula 2, an example of a disc-shaped organic supramolecule is a compound of the following chemical formula 3, and an example of a conical organic supramolecule is the following chemical formula 4 Each of these compounds is exemplified.

Unlike organic macromolecules in which monomers are linked by covalent bonds, such organic supramolecules form a certain structure by physical secondary bonds such as van der Waals forces. Such organic supramolecules self-assemble with an appropriate temperature, concentration, external magnetic field, electric field, etc. to form a specific microstructure. The organic supramolecule of Formula 1 used in the present invention corresponds to a fan-shaped dendrimer. Fan-shaped molecules form a plate-like structure 1 by self-assembly, and the plate-like structures gather to form a cylindrical form 3, and further form a three-dimensional structure 4 in which the cylinders are arranged in a hexagonal shape (FIG. 1a). In addition, in the case of the organic supramolecule 5 having a conical shape, the conical shape is self-assembled to form a spherical shape 6, and the spheres are gathered and arranged in a fixed structure 7 in a three-dimensional space (FIG. 1b).

In the present invention, the thin film in the step (b) is preferably formed using a spin coating method, a rubbing process, or a water surface expansion method in which a thin film is formed on the water surface, and the step (c) uses temperature. It is desirable to raise the temperature above the phase transformation temperature of the liquid crystal of the organic supramolecule and then slowly cool it. In the stage (d), it is preferable that the central portion is selectively stained using a RuO ₄ (ruthenium tetroxide) compound, and in the stage (e), a reactive ion etching method is used. desirable.

In the present invention, a method of synthesizing CNTs into the nano pattern of the substrate can be manufactured using a CNT manufacturing method widely known in the art. It can be grown vertically by the method, thermochemical vapor phase method, electrophoresis method or mechanical method (KR2002-0001260A).

The present invention may further include the step of treating the plasma at the end of the CNT array arranged in a vertical manner to expose carboxyl groups. Thus, after exposing the carboxyl group to the terminal portion by plasma treatment, various bioreceptors can be chemically fixed.

The present invention also provides a CNT array produced by the above method with a bio selected from the group consisting of protein, peptide, amino acid, DNA, PNA, enzyme substrate, ligand, cofactor, carbohydrate, lipid, oligonucleotide, and RNA. Provided is a method for producing a biochip characterized by attaching a substance or a bioreceptor.

Attaching a bioreceptor to a CNT can be done by applying a charge with a polarity opposite to the net charge of the biomaterial or bioreceptor to the CNT (KR2003-0014997A), or using a binding aid. Can do. A desirable binding aid may be a chemical substance having an aldehyde, amine, or imine group at the end of the carbon group.

The present invention also provides a method for producing a biochip, characterized in that a bioreceptor having an amine group (NH ₂ ) is fixed to the CNT array having a carboxyl group exposed at the terminal by an amide bond. In the present invention, it is desirable to use a coupling agent and a coupling aid in order to induce an amide bond.

Bioreceptors such as proteins, peptides, and amino acids each have their own isoelectric point, and have a net charge charged to neutral, cation, anion, etc. depending on the strength of ions in the solution and pH conditions. . In addition, by adjusting the state of the solution, it is possible to arbitrarily adjust the electrostatic interaction and hydrophobic interaction of these bioreceptors and CNTs having a constant charge, etc. Each different type of bioreceptor can be moved or arrayed.

The present invention also provides a biomaterial or bioreceptor selected from the group consisting of protein, peptide, amino acid, DNA, PNA, enzyme substrate, ligand, cofactor, carbohydrate, lipid, oligonucleotide, and RNA in the CNT array. A biochip characterized by being bonded is provided.

According to the present invention, a protein-receptor that selectively binds to a target protein involved in a disease can be selectively attached by applying an electric field to CNTs nano-arrayed on one chip. In addition, by applying an electric field having a different polarity to each CNT, it is possible to selectively attach biomaterials and bioreceptors that can interact with various types of target proteins involved in various diseases. Accordingly, various types of diseases can be accurately diagnosed in a large amount at once on a single chip in a quick time.

The term “biochip” as used in the present invention is a concept encompassing that a nanomaterial is attached with a biomaterial or a receptor that binds to or reacts with the biomaterial, and includes a bioarray and a biosensor. Is defined as

The present invention uses a columnar nanopattern formed using organic supramolecular self-assembly and selective staining of a metal compound as a mask to form a catalyst pattern for CNT synthesis, in which CNTs are arranged. It has the effect of providing a method of manufacturing a CNT array characterized by the above. Furthermore, the present invention has an effect of providing a method of manufacturing a biochip by attaching a biomaterial or a bioreceptor that binds to the biomaterial to the CNT array.

Hereinafter, the present invention will be described more specifically.

In the present invention, a thin film layer is formed on a substrate using Fe, Ni, Co or the above three metal catalyst alloys as a metal catalyst for vertically growing CNTs on the substrate by thermal evaporation, electron beam evaporation, sputtering, or the like. . The formed metal thin film is formed as a metal catalyst array using the following organic supramolecular nanopattern (FIG. 2).

According to a preferred embodiment of the present invention, a thin film is first formed on a substrate by preparing a 1 wt% solution of the organic supramolecule of Formula 1 using tetrahydrofuran as a solvent. At the time of forming a thin film, a spin coating method, a rubbing process, or a water surface spreading method in which a thin film is formed on the water surface is mainly used. In the above embodiment, a silicon wafer on which Fe, Ni, Co, or the above three metal catalyst alloys used as a metal catalyst was deposited as a substrate was used, and the surface was not modified (FIG. 2a).

Next, the temperature is raised above the phase transformation temperature of the liquid crystal so that the organic supramolecules are self-assembled. In the case of the organic supramolecule used in the present invention, since the phase transformation temperature of the liquid crystal is about 230 ° C., the temperature is raised to 240 ° C. and then slowly cooled, and the organic supramolecule has a fine structure having a cylindrical arrangement. Formed (FIG. 2b).

A process in which organic supramolecules are self-assembled by annealing according to a preferred embodiment of the present invention is as follows.

Although the properties of organic supramolecules can be modified by annealing, suitable starting materials for annealing include organic supramolecules produced by laser pyrolysis. In addition, organic supramolecules used as starting materials may undergo one or more preheating steps under different conditions, but additional processing is required in the annealing of organic supramolecules formed by laser pyrolysis. Can improve crystallinity, remove contaminants such as elemental carbon, and possibly change the stoichiometry, for example by combining elements from additional oxygen or other gas phase or non-gas phase compounds. it can. The organic supramolecule is generally desirably heated in an oven or the like so as to provide uniform heating. The processing conditions are generally mild and no significant amount of particle sintering occurs. Therefore, it is desirable that the heating temperature be lower than the melting points of both the starting material and the product. If annealing involves a compositional change, the molecular size and morphology can be changed even at mild heating temperatures.

Self-assembled structures are generated on and / or in the surface of the substance / substrate. Self-assembled structures are positioned within boundaries, and each structure can form an element as a component of a multi-element circuit or mechanism in a manner in which the structure forms a positioned island. In particular, each structure may be an integrated electronic circuit component, and this component may include, for example, electrical components, optical elements, and photonic crystals.

In order to form a structure within a predetermined boundary, the formation of a self-assembled structure of interest generally requires a process for determining the limit of the structure and a separate self-assembly process. The process of determining the boundaries usually uses external forces to determine the limits of the structure. In general, the self-assembly process itself cannot determine the boundaries of the structure. Self-assembly is based on the natural sensing function of the composition / substance that results in a natural order within the structure when the composition / substance is combined. In general, the position determination step can be performed before and after the self-assembly process, but the nature of the processing steps may indicate a specific order. The net effect causes a self-assembled structure with areas correspondingly covered by the nanoparticles within the boundary and areas outside the boundary without such coverage. In addition, the step of defining a separate boundary leads to the self-assembly step by activating the self-assembly step within the boundary or deactivating the region outside the boundary. In general, an external force must be applied to perform the activation process or the deactivation process.

It can be confirmed through a transmission electron microscope that organic supramolecules form a certain structure on the bulk. As a result of manufacturing the sample by the process under the same conditions as those used in the present invention, a result as shown in FIG. 3 can be obtained, and this allows the organic supramolecule to form a regular structure in a hexagonal column shape. Recognize.

According to a preferred embodiment of the present invention, a process of selectively staining a metal compound in a certain structure formed by self-assembly of the organic supramolecule is as follows.

First, a RuO ₄ solution and a substrate coated with an organic supramolecular thin film are charged together in a glass container so as not to come into direct contact with the solution. While RuO ₄ vapors of RuO ₄ solution is diffused in the gas phase in the process, it is staining the organic supramolecular thin film on a substrate. The stained RuO ₄ vapor will cause a chemical reaction selectively in specific parts of the structure.

Although RuO ₄ is used in the present invention, any metal compound that can selectively stain the structure formed by OsO ₄ (oscium tetroxide) or other organic supramolecules can be used.

According to a preferred embodiment of the present invention, after passing through the staining process, an organic supramolecular layer on the surface is partially removed after an etching process, and finally a nanopatterned device is obtained. Such an etching process can be used without limitation as long as it is a commonly used method in the semiconductor element process. For example, an etching solution such as a KCN-KOH mixed solution or an aqueous HF solution can be used, or reactive ion etching (RIE) or ion milling can be used.

In a preferred embodiment of the present invention, the fabricated metal compound is stained to form an alloy array of iron, cobalt, nickel or the three metal catalysts used as a catalyst for the synthesis of CNTs on a substrate. When ion milling is performed using the nano pattern as a mask, a metal catalyst nano pattern is finally formed on the substrate.

A method of synthesizing CNTs can be manufactured using a CNT production method widely known in the art, and C ₂ H ₂ , CH ₄ , C ₂ H ₄ , and C ₂ H ₆ are used as reaction gases. CO gas is used, and the synthesis method is vertically grown by plasma chemical vapor deposition, thermal chemical vapor deposition, electrophoresis or the like. When producing CNTs using this metal catalyst nanopattern, since the diameter of one pattern is 10 nm or less, it is possible to produce CNTs having a very small diameter.

The present invention also includes the step of treating the ends of vertically grown CNTs with plasma to immobilize the biomaterial and opening the end caps to introduce carboxyl groups (FIG. 3).

The CNT nanoarray formed as described above according to a preferred embodiment of the present invention can be used as an important surface substrate in reacting various kinds of biological materials to form an array of a desired form. Will perform very important functions in producing highly integrated and miniaturized biochips.

Generally, a biochip is manufactured by a method in which a biomolecule is directly linked to a substrate or a biomolecule is linked through a linker molecule. For example, in the case of a DNA chip, protein chip, or protein sensor, when a biomaterial such as DNA, antibody, or enzyme is to be immobilized at the CNT end, the carboxyl group introduced at the CNT end and the amine group of the biomaterial The target biochip can be produced by reacting and fixing with an amide bond.

Among the biochips according to the present invention, a method for manufacturing a DNA chip includes a step of manufacturing a DNA chip by fixing a probe manufactured in advance to a solid surface by a spotting method. A probe having amine groups attached thereto is dissolved in 1X to 7X, preferably 2X to 5X, most preferably 3X SSC (0.45 M NaCl, 15 mM C ₆ H ₅ Na ₃ O ₇ , pH 7.0) buffer solution; After spotting the CNT end where the carboxyl group is exposed using a microarrayer, the probe is reacted to fix the CNT end to the CNT end. At this time, the concentration of the probe is 10 pmol / μl or more, desirably 50 pmol / μl or more, and most desirably 100 pmol / μl or more, and the amine group bonded to the probe and the carboxyl group and amine group introduced at the CNT end. Are reacted and bonded under 70-90%, preferably 80% humidity conditions for 4-8 hours, desirably 5-7 hours, most desirably 6 hours. At this time, EDC / NHS was used as an amide upring agent.

Hereinafter, in order to describe the present invention more specifically, examples will be described. However, the embodiments according to the present invention can be modified in various other forms, and the scope of the present invention is not limited to the following embodiments. The embodiments of the present invention are provided for those skilled in the art to more safely explain the present invention.

Synthesis of Organic Supramolecule The organic supramolecule of Formula 1 used in the present invention was synthesized by the process of Reaction Formula 1 below. When confirmed with a scanning electron microscope, it was confirmed that the organic supramolecules have a regular cylindrical structure of nanometer level or less (FIG. 4).

(Reaction Formula 1)

Deposition of metal catalyst for synthesizing carbon nanotubes In the present invention, thermal deposition, electron beam, sputtering, etc. are used to form a thin film of metal catalyst Fe, Ni, Co or the above three metal catalyst alloys for CNT synthesis. The metal catalyst was deposited on a silicon wafer (FIG. 2a).

Formation of organic supramolecular thin film This organic supramolecular sample was dissolved in a tetrahydrofuran (THF) solvent and spin coated on a silicon wafer to form a thin film (FIG. 2a). In the present invention, spin coating is performed at a speed of 2000 to 3000 rpm for 10 to 30 seconds, and the thickness of the thin film can be appropriately changed in this process.

Annealing was raised to 240 ° C. and then gradually cooled to form a regular microstructure (FIG. 3b). In the case of the organic supramolecule used in the present invention, self-assembly occurs at 240 ° C., and this depends on the organic supramolecule used. At this temperature, the organic supramolecule has sufficient mobility for self-assembly, and self-assembly is performed with the most stable structure. In the case of the organic supramolecule used in the present invention, a three-dimensional structure in which cylinders are arranged in a hexagonal shape is the most stable structure. FIG. 4 is a transmission electron microscope photograph showing that organic supramolecules form a regular structure in the form of a hexagonal column.

Steining using RuO ₄ (ruthenium tetroxide) In the case of the present organic supramolecule, the central portion can be selectively stained using the RuO ₄ compound, so that the sample is exposed to the vapor on RuO ₄ for several minutes. And RuO ₄ metal compound was stained in the central part (FIG. 2c).

When exposing the sample to a RuO _4, RuO ₄ metal compound is staining is diffused into the gas phase to the organic supramolecular thin film. The RuO ₄ metal compound chemically reacts with a specific reactive group (ether bond, alcohol, benzene ring, amine, etc.), and in the case of the organic supramolecule used in the present invention, the region corresponding to the central portion of the cylinder is RuO _4. Stained with a metal compound.

Metal compounds stained by the organic supramolecules used can be substituted. For example, in the case of OsO ₄ (oscium tetroxide), it is chemically stained to a reactive group such as a carbon double bond, alcohol, ether bond, or amine.

After the etching, after a reactive ion etching process, the central portion remains due to the difference in etching rate (FIG. 2c). FIG. 5 is a photograph of a scanning electron microscope showing the form of the dots formed in this way. In the present invention, etching is performed for about 100 seconds using CF ₄ gas. Since the etching time varies depending on the equipment, this cannot be said to be applicable in all cases, and a test stage for setting conditions is necessary.

Formation of metal catalyst nanopattern The metal catalyst thin film layer was etched using the organic supramolecular nanopattern obtained by staining the metal compound obtained in the processes of Examples 1 to 6 as a mask to form a metal catalyst nanopattern. . In the present invention, when the metal catalyst thin film layer is formed between the substrate and the organic supramolecular thin film for CNT synthesis, the formed nanostructure of the point structure serves as a mask in the subsequent etching process (FIG. 2c). That is, the lower end of the spot pattern where the RuO ₄ compound is stained is not etched, and the intermediate thin film layer on which the surface appears is etched so that the pattern formed by the organic supramolecules moves to the intermediate thin film layer. become. Although this differs depending on the material used as the intermediate thin film layer, in the case of a metal thin film layer for CNT synthesis as in the present invention, etching by ion milling is possible, and the etching conditions depend on the characteristics of each thin film layer. (Figure 2d).

Manufacture of CNT array Example of causing glow discharge by applying high frequency power to both electrodes while supplying reaction gas such as C ₂ H ₂ , CH ₄ , C ₂ H ₄ , C ₂ H ₆ , CO, etc. into the chamber CNTs were synthesized and grown in the vertical direction on the metal catalyst nanoarray formed in Step 7. The synthesized CNTs form a CNT array by a regular arrangement of metal catalysts immobilized on a substrate (FIG. 2e). Further, the vertically grown CNTs are treated with plasma in a manner similar to the method disclosed in the prior art (Huang, S. et al., J. Phys. Chem. B, 106: 3543, 2002). Then, after removing the terminal cap and introducing a carboxyl group, various bioreceptors can be chemically immobilized.

Manufacture of biochip by attaching biomaterial or bioreceptor to CNT array Does attaching bioreceptor to the CNT array manufactured in Example 8 apply a charge of polarity opposite to the net charge of bioreceptor to CNT? (KR2003-0014997A), or attached using a binding aid (FIG. 2f). A desirable binding aid can be a chemical with an aldehyde, amine or imine group at the end of the carbon group.

In addition, a biochip can be manufactured by fixing a bioreceptor having an amine group (NH ₂ ) to the end of the CNT array where the carboxyl group manufactured in Example 8 is exposed by an amide bond. At this time, EDC (1-ethyl-3- (3-dimethylaminipropyl) arbodiimide hydrochloride) is used as a coupling agent, and NHS (N-hydroxysuccinimide) and NHSS (N-hydroxy) are used as auxiliary agents for the coupling agent. It is desirable to use sulfosuccinimide).

Fig. 1a shows a model of self-assembled organic supramolecules. Fig. 1a shows a disk-shaped or disk-type dendrimer 1 and a fan-shaped organic supramolecule 2 forming a cylindrical form 3 by self-assembly, and these cylinders are arranged in a hexagonal shape. FIG. 1b shows that a rod-shaped chain or cone-shaped molecule 5 forms a sphere 6 by self-assembly, and these spheres gather to form a certain structure in a three-dimensional space. 7 shows that it is arranged. 1 is a schematic view of a nano pattern and CNT array formation process for manufacturing a biochip according to the present invention. It is the schematic which shows the process of removing the cap which exists in the grown CNT terminal part, and simultaneously introduce | transducing a carboxyl group. It is a photograph of the transmission electron microscope which shows that an organic supramolecule forms the regular structure of a hexagonal column form. 4 is a scanning electron microscope photograph of a nanopattern formed according to the present invention.

Explanation of symbols

1 Disc-shaped or disk-shaped dendrimer 2 Fan-shaped organic supramolecule 3 Cylindrical form 4 Three-dimensional structure 5 Conical molecule 6 Spherical shape 7 Constant structure

Claims (17)

A method of fabricating a carbon nanotube (CNT) nanoarray comprising the following steps:
(A) forming a metal catalyst thin film selected from the group consisting of Fe, Ni, Co and an alloy of the metal on a substrate;
(B) forming an organic supramolecular thin film that induces self-assembly on the metal catalyst thin film;
(C) a step of self-assembling the organic supramolecules by annealing to form a regular structure;
(D) selectively staining a metal compound in a regular structure formed by self-assembly of the organic supramolecules;
(E) forming a nano-pattern of organic supramolecules in which the metal compound is stained by removing a portion where the metal compound is not stained through etching using the thin film in which the metal compound is selectively stained as a mask; ;
(F) forming a metal catalyst nanopattern through ion milling using the organic supramolecular nanopattern of the metal compound as a mask; and (g) vertically aligning the CNT with the metal catalyst nanopattern. The stage to arrange. 2. The method according to claim 1, wherein the organic supramolecule is a disk-type dendrimer, a fan-shaped organic supramolecule, or a conical organic supramolecule. 3. The method of claim 2, wherein the organic supramolecule is a compound of Formula 1.

2. The method according to claim 1, wherein in step (c), the temperature is raised above the phase transformation temperature of the organic supramolecular liquid crystal used and then gradually cooled. 2. The method according to claim 1, wherein the metal compound in the step (d) is RuO ₄ (ruthenium tetroxide). 2. The method of claim 1, further comprising the step of exposing the CNT array ends synthesized in the vertical direction to plasma to expose carboxyl groups. A bioreceptor selected from the group consisting of proteins, peptides, amino acids, DNA, PNA, enzyme substrates, ligands, cofactors, carbohydrates, lipids, oligonucleotides and RNA in the CNT array obtained by the method of claim 1. A method for producing a biochip characterized by being attached. 8. The method of claim 7, wherein the bioreceptor is attached by applying an electric field to the CNTs. 9. The method according to claim 8, wherein a charge having a polarity opposite to the net charge of the bioreceptor is applied to the CNT. 9. The method according to claim 8, wherein the bioreceptor is attached to the CNT array using a binding aid. 11. The method according to claim 10, wherein the binding aid is a chemical substance having an aldehyde, amine or imine group at the carbon group end. A method for producing a biochip, comprising fixing a bioreceptor having an amine group (NH ₂ ) to a terminal carboxyl group of a CNT array obtained by the method of claim 6 with an amide bond. 13. The method according to claim 12, wherein a coupling agent and a coupling aid are used to induce an amide bond. A bioreceptor selected from the group consisting of proteins, peptides, amino acids, DNA, PNA, enzyme substrates, ligands, cofactors, carbohydrates, lipids, oligonucleotides and RNA, fabricated according to claim 7 A biochip characterized by that. A method for detecting a reaction between a biomaterial and a bioreceptor, wherein the biochip according to claim 14 is used. A bioreceptor produced by the method of claim 12 and selected from the group consisting of proteins, peptides, amino acids, DNA, PNA, enzyme substrates, ligands, cofactors, carbohydrates, lipids, oligonucleotides and RNA on a CNT nanoarray A biochip characterized in that is fixed by an amide bond. A method for detecting a reaction between a biomaterial and a bioreceptor, characterized in that the biochip of claim 16 is used.

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