KR20040107763A - A conductive carbon nanotubes dotted with metal and method for fabricating a pattern using the same - Google Patents

Abstract

PURPOSE: A method for manufacturing conductive carbon nanotube(CNT) having scattered metals thereon and a patterning method using the same are provided to improve electroconductivity and surface density, thereby being suitably used as a biosensor. CONSTITUTION: The method for manufacturing conductive CNT having scattered metals thereon comprises: (a) providing CNT having carboxyl groups; (b) binding the carboxyl groups and amino groups of a compound having both amino groups and thiol groups to provide CNT modified with a thiol group; and (c) binding the thiol groups of the modified CNT to metal. The patterning method using the conductive CNT comprises: (a) providing a substrate having thiol groups exposed thereon; (b) binding the metal of the CNT to the thiol groups of the substrate surface; and (c) binding another conductive CNT to the CNT bound to the substrate surface.

Description

A conductive carbon nanotubes dotted with metal and method for fabricating a pattern using the same}

Field of invention

The present invention is a CNT pattern having a high surface density by laminating a conductive CNT, a method of manufacturing the same, and a method of manufacturing the conductive CNT on a carboxylated carbon nanotube (CNT) on a substrate-formed substrate surface by a chemical method. It relates to a method of forming a.

Background of the Invention

CNT is a carbon allotrope composed of carbon present on the earth in large quantity. It is a material in which one carbon is combined with other carbon atoms in hexagonal honeycomb pattern to form a tube, and the diameter of the tube is nanometer (nm = 1 billionth of a meter). ) Is an extremely small area of matter. CNT is known as a perfect new material that has excellent mechanical properties, electrical selectivity, excellent field emission characteristics, high efficiency hydrogen storage medium properties and few defects among existing materials.

Therefore, CNTs are used for electron emitters, vacuum fluorescent displays (VFDs), white light sources, field emission displays (FEDs), lithium ion secondary battery electrodes, hydrogen storage fuel cells, nanowires, nanocapsules, and nanoparticles. It shows unlimited applications in tweezers, AFM / STM tips, single-electron devices, gas sensors, medical and engineering micro components, and high performance composites. Since CNTs have excellent mechanical robustness and chemical stability, can exhibit both semiconductor and conductor properties, and have a small diameter and relatively long lengths, CNTs are excellent materials for flat panel display devices, transistors, and energy storage materials. Visible, its applicability as nano-sized various electronic devices is very large.

Single-walled CNTs have been chopped to provide more diverse applications of the above characteristics. The CNTs thus cut have mainly -COOH chemical groups on the cut ends and sidewalls. These chemical functional groups have been used to chemically attach various materials to modify the properties of CNTs. Furthermore, by substituting the -SH group for the functional group of CNT by chemical mechanism, the report was patterned on the surface by micro contact printing technique (Nan, X. et al., J. Colloid). Interface Sci., 245: 311-18, 2002) and reports on the adhesion of CNTs to surfaces using electrostatic methods (Rouse, JH et al., Nano Lett., 3:59). -62, 2003). However, the former has the disadvantage that the surface density of CNTs is low and the bonding strength is weak, and the latter has the fatal disadvantage that the patterning method of selectively fixing to the surface cannot be applied. Therefore, a new type of surface fixation method is urgently needed.

Recently, studies on reaction detection through electrochemical changes of CNTs immobilized with biomaterials have been made using the electrical, semiconducting or structurally stable properties of CNTs (Dai, H. et al., ACC.Chem Res., 35: 1035-1044, 2002; Sotiropoulou, S. et al., Anal.Bioanal.Chem., 375: 103-105, 2003; Erlanger, BF et al., Nano Lett., 1: 465-. 467, 2001; Azamian, BR et al., JACS, 124: 12664-12665, 2002).

On the other hand, a representative example of the protein-ligand reaction is an avidin (avidin) -biotin (biotin) reaction, which forms a channel using CNT on the polymer-treated substrate, and then the electrochemical method of streptoavidin Binding was measured (Star, A. et al., Nano Lett., 3: 459-463, 2003).

Creating a high-density CNT multilayer, attaching DNA to it, and detecting complementary binding DNA can be done by genotyping, mutation detection, pathogen identification, etc. useful. PNA (peptide nucleic acid: DNA analogue) has been reported to be site-specifically fixed to a single-walled CNT and detected complementary binding to the target DNA (Williams, KA et al., Nature, 420 : 761, 2001). In addition, an oligonucleotide is immobilized to a CNT array by an electrochemical method, and a DNA is detected by a guanidine oxidation method (Li, J. et al., Nano Lett., 3: 597-602). , 2003). However, these did not apply CNT to the manufacture and development of biochips.

Recently, a high capacity biomolecular detection sensor (WO 03/016901 A1) using CNTs is known. The present invention relates to a multichannel type biochip obtained by arranging a plurality of CNTs by attaching a plurality of CNTs on a substrate and attaching various kinds of receptors.

CNT attracts attention as a biosensor because, firstly, no labeling is required and secondly, the reaction can proceed in an aqueous solution without modification of the protein. The combination of new nanomaterials and biological systems will create important applications in disease diagnosis, genetics, and nanobiotechnology.

On the other hand, the application of CNTs in the field of biotechnology has emerged in recent years. Glucose sensor, detection of proteins, detection of specific DNA sequences (Anal. Bioanal. Chem., 375: 103-105, 2003; Proc. Natl. Acad. Sci. USA, 100 (9): 4984-9, 2003; Anal. Bioanal. Chem., 375: 287-293, 2003). Biomolecular screening in CNT-based multilayers can increase the amount of biomolecules such as DNA immobilized due to its large surface area and excellent electrical conductivity, and increase detection sensitivity to biomolecules.

In addition, research is being actively conducted to increase the water solubility of CNTs corresponding to inorganic materials together with a technique of binding various functional groups to CNTs. CNTs covalently attached to DNA not only dissolve well in water or organic solvents, but also have properties that allow CNTs to disperse well in aqueous solutions. It plays an important role in the development of water soluble CNTs, self-assembly surfaces, chemical or biosensors (Nat. Mater., 2 (5): 338-42, 2003; Science, 265: 1850, 1994; Adv. Mater., 10: 701-3, 1998).

The recent trend of combining BT (biotechnology) and NT (nanotechnology) has facilitated the development of hybrid nanomaterials using the properties of biomaterials that can specifically bind. DNA has been spotlighted as smart nanowires that can be bound to desired locations (in the present invention where gold nanocrystals are attached).

As such, a combination of different disciplines is creating new frontier technology. In particular, the combination of information technology (IT), NT and BT has become an indispensable field. This enables fast and accurate digital information, such as electrical detection, to be used for measuring analog data such as the presence and reactivity of biomaterials (Chen, J. et al., JACS, 122: 657-660, 2000; Dahne, L et al., JACS, 123: 5431-5436, 2001).

Currently, the method of detecting reaction results in biochips is the most common method using conventional fluorescent materials and isotopes (Toriba, A. et al., Biomed. Chromatography: BMC., 17: 126-132, 2003; Raj, SU et al., Anal. Chim. Acta, 484: 1-14, 2003; Peggy, AT et al., J. Microbio.Meth., 53: 221-233, 2003), making electrical properties easier and more accurate. As new methods of measurement are attempted, the need for a new material called CNT is growing.

An object of the present invention is to overcome the problems of the prior art, to provide a CNT excellent in electrical conductivity by interposing a metal and a method of manufacturing the same.

Another object of the present invention is to provide a method for forming a CNT pattern by laminating metal-dispersed CNTs on a substrate.

Another object of the present invention is to provide a CNT film having a high surface density and excellent electrical conductivity.

1 is a schematic diagram showing a manufacturing process of carbon nanotubes (CNT) interspersed with gold nanoparticles.

FIG. 2 is a schematic diagram illustrating a process of forming a polymer mask pattern having a shape for integrating the CNT of FIG. 1 using photolithography technology on a silicon substrate.

3 is a process chart showing a manufacturing method of a CNT pattern interspersed with gold nanoparticles. (a) is a schematic diagram of exposing a thiol group (-SH) on a patterned substrate surface and fixing a CNT monolayer interspersed with gold nanocrystals. (b) is a schematic diagram of fixing CNTs interspersed with another gold nanocrystal by using a chemical having two thiol groups in the CNT monolayer formed in (a). (c) is a schematic diagram of a method of increasing the surface density of CNTs in which gold nanoparticles are interspersed on the surface by repeating the method of (b). (d) is a schematic diagram showing the method of laminating CNTs interspersed with gold nanoparticles at high density by repeating the method of (c). (e) is a schematic diagram showing the result of forming a pattern by densely stacking CNTs interspersed with gold nanoparticles on a substrate.

FIG. 4 is a schematic diagram showing that the gold nanoparticles selectively interact with various kinds of target biomaterials after attaching various receptors having functional groups that bind or react with gold crystals on the interspersed CNT surface. 1 and 2 represent bioreceptors that can react with the target biomaterial, and 4 represent target biomaterials that can react with the bioreceptor. 3 represents an oligonucleotide in a bioreceptor, 5 represents a complementary nucleic acid capable of hybridizing with the oligonucleotide immobilized on a metal of a conductive CNT, and 6 represents a general biomaterial that is not reactive.

5 (a) is a TEM photograph of CNTs interspersed with gold crystals obtained by forming a thiol group (-SH) on CNTs and then reacting gold colloids, and (b) shows no thiol group (-SH) formed. TEM image of CNT reacted with gold colloid.

FIG. 6 is an enlarged HR-TEM photograph of FIG. 5.

7 is an XPS doublet spectrum for gold crystals interspersed with CNTs.

In order to achieve the above object, the present invention comprises the steps of (a) providing a CNT having a carboxyl group; (b) combining the carboxyl group of the CNT with an amino group of a chemical compound having an amino group and a thiol group at the same time to obtain a thiol group-modified CNT; And (c) bonding a metal to a thiol group of the CNT modified with the thiol group obtained in the above step.

The chemical having both an amino group and a thiol group is preferably NH ₂ -R ₁ -SH, wherein R ₁ is a C _1-20 saturated hydrocarbon, unsaturated hydrocarbon, or aromatic organic group.

The step (a) may be characterized by treating the CNT with an acid, the metal may be characterized in that the gold (Au).

The step (c) may be characterized in that by reacting the metal nanoparticles or colloid to the CNT modified with a thiol group, and then reducing.

The present invention also provides a conductive CNT in which a metal having a form of CNT- (CONH-R ₁ -SM) r is interspersed. Here, M represents a metal, r is one or more natural numbers, the metal may be characterized in that gold.

In order to achieve the above another object, the present invention (a) providing a substrate having a thiol group exposed on the surface; (b) bonding a metal of the conductive CNT interspersed with the metal to a thiol group on the surface of the substrate; And (c) stacking the CNTs by bonding the conductive CNTs interspersed with the metal to the CNTs attached to the substrate, thereby providing a pattern of the conductive CNTs.

The present invention also provides a method comprising the steps of: (a) providing a substrate having a thiol group exposed on the surface; (b) bonding a metal of the conductive CNT interspersed with the metal to a thiol group on the surface of the substrate; (c) depositing a conductive CNT by bonding the conductive CNT to a conductive CNT attached to the substrate; And (d) repeating step (c) to increase the density of the conductive CNTs, and the substrate- [CONH-R ₂ -S-Au prepared by the above method. A conductive CNT film having a structure of -CNT-Au- (SR ₃ -S-Au-CNT-Au) p] q is provided. Where p and q are one or more natural numbers.

The step (a) may be characterized in that the substrate having an amino functional group exposed to the surface is treated with a chemical having a carboxyl group and a thiol group, thereby forming an amide bond between the amino group on the substrate and the carboxyl group of the chemical.

The chemical substance having a carboxyl group and a thiol group at the same time is preferably a substance of HOOC-R ₂ -SH, wherein R ₂ is a C _1-20 saturated hydrocarbons, unsaturated hydrocarbons or aromatic organic groups.

The substrate having an amino functional group exposed to the surface may be obtained by treating the substrate with aminoalkyloxysilane.

The coupling of the amino group and the carboxyl group may be characterized by using a coupling agent and a base, and the step (c) may be characterized by using a linker having a double thiol functional group. The linker having the double thiol functional group is preferably HS-R ₃ -SH, wherein R ₃ is a C _1-20 saturated hydrocarbon, unsaturated hydrocarbon or aromatic organic group.

In addition, the substrate may be characterized in that the photoresist or polymer pattern is formed to attach the conductive CNT at a desired position, the substrate is characterized in that selected from the group consisting of glass, silicon, fused silica, plastic and PDMS You can do

The term 'dot' used in the present invention is defined as a metal bonded to the CNT in the shape of a dot.

In the present invention, metal particles are interspersed with CNTs to improve the electrical properties of existing CNTs, and CNTs interspersed with metal nanocrystals are repeatedly laminated on a solid substrate coated with a chemical functional group through chemical bonding to have high surface density. A CNT pattern (or film) was produced.

According to the present invention, it is possible to form a pattern of a desired shape at a room temperature at a desired position, deviating from the limitations of the prior art completed by growing CNTs from a catalyst placed at a predetermined position. That is, the method of attaching the CNT to the substrate is largely an electrical method and a chemical method. While the electrical method allows for relatively free positioning of the CNTs, the chemical method involves modifying the substrate with a specific functional group and then immersing the CNTs in a suspended solution for a certain period of time. Is very difficult.

In order to form a variety of patterns by combining CNTs at desired positions, it is necessary to expose only a specific part of the substrate, and to withstand a long time in a solution in which CNTs are dispersed. It should be possible.

The present invention improves the disadvantages of the prior art by forming a pattern of the substrate using a polymer so as to take full advantage of the chemical method. In addition, it is possible to solve the problems of the prior art such as the difficulty of patterning polymers due to high temperature mechanisms such as plasma chemical vapor deposition, thermal chemical vapor deposition, and the absence of chemical functional groups such as -COOH obtained in the cutting process in strong acids. Do.

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

1. Preparation of CNTs Interspersed with Gold Nanocrystals

1 is a schematic view showing a method of dot (dot) the gold particles using a redox method to the CNT cut in a strong acid. CNTs cut by strong acids have a carboxyl functional group (-COOH). The carboxyl functional group of the CNT was combined with the amino functional group of a linker having an amino (-NH ₂ ) functional group and a thiol (-SH) functional group.

In this case, DCC (1,3-dicyclohexyl carbodiimide), HATU ( O- (7-azabenzotriazol-1-yl) -1,1: 3,3-tetramethyl uroniumhexafluorphosphate), HBTU ( O- ( benzotriazol-1-yl) -1,1,3,3-tetramethyluronium hexafluorophosphate), HAPyU ( O- (7-azabenzotriazol-1-yl) -1,1: 3,3-bis (tetramethylene) uronium hexafluorphosphate), HAMDU ( O- (7-azabenzotriazol-1-yl) -1,3-dimethyl-1,3-dimethyleneuronium hexafluorphosphate), HBMDU ( O- (benzotriazol-1-yl) -1,3-dimethyl-1,3-dimethyleneuronium It is preferable to use DIEA (diisopropylethylamine), TMP (2,4,6-trimethylpyridine), NMI ( N -methylimidazole) or the like as a base. In addition, use of the EDC (1-ethyl-3- ( 3-dimethylamini-propyl) arbodiimide hydrochloride) as a coupling agent when using water as a solvent, NHS N -hydroxysuccinimide) as an adjunct of a coupling agent, NHSS (N-hydroxysulfosuccinimide), etc. It is desirable to. The coupling agent serves to form an amide bond (-CONH-) with a -COOH functional group and a -NH ₂ functional group, and the base and the auxiliary agent help to increase efficiency when the coupling agent forms an amide bond. do.

The linker having the amino functional group and thiol functional group at the same time is preferably a chemical represented by NH ₂ -R ₁ -SH. Here, R ₁ is C _1-20 saturated hydrocarbons, unsaturated hydrocarbons or aromatic organic groups.

Gold nanoparticles such as HAuCl ₄ , HAuCl ₄ · 3H ₂ O, HAuBr ₄ , AuCl ₄ K, AuCl ₄ Na, AuBr ₄ K, AuBr ₄ Na, and more preferably HAuCl ₄ gold in the CNT modified with the thiol functional group After the reaction of the colloid to generate a gold nucleation site (gold nucleation site), the gold nanoparticles were reduced by using an ion extraction reaction (ion extraction reaction) as shown in the following [Reaction Scheme 1] and the gold crystals were dotted on the CNT .

Scheme 1

^{_{AuCl 4 - (aq) + N}} (C 8 H 17) 4+ (toluene) → N (C 8 H 17) 4+ AuCl 4- (toluene)

^{_{mAuCl 4 - (toluene) + n}} CNT-CONH-C 2 H 4 SH (toluene) + 3me - →

^{_{4mCl 4 - (aq) + (}} Au m) (CNT-CONH-C 2 H 4 SH) n (toluene)

Finally, a conductive CNT dotted with gold having a form of 'CNT- (CONH-R ₁ -S-Au) r' is obtained. Where r is one or more natural numbers.

Instead of gold, silver (Ag) nanoparticles, platinum (Pt) nanoparticles, iron (Fe) nanoparticles, nickel (Ni) nanoparticles, cobalt (Co) nanoparticles and the like may also be used. At this time, the metal particles of the oxidized form may be dotted by reducing the metals to CNT modified with a specific chemical functional group such as a thiol functional group by using a redox reaction (Jiang, K. et al., Nano Lett., 3 : 275-277, 2003).

2. Formation of multichannel type pattern on substrate

In order to fix CNTs to a substrate such as glass, silicon wafers and plastics, it is necessary to form a pattern that can withstand a long time in a liquid phase. There are two ways to form a pattern on a substrate. The first method is to remove the CNT layer by using a negative photosensitive agent, the CNT is deposited, and then remove the remaining photoresist layer. The second method is to use a photolithography method to form the polymer substrate. It can be formed by etching.

In the specific process, first, a method of using a negative photoresist film is coated with a photosensitive film such as SU-8 (Dowcorning co.) To remove only a portion of the photolithography process to deposit CNT, and to remove the remaining photoresist film after deposition. The most common method of the semiconductor process of the formula can be used.

Second, as shown in FIG. 2, spin coating a photoresist film on the silicon substrate (a) (b), exposing using a mask of a certain shape (c), and developing the photo A primary pattern through a lithography process is formed on a silicon substrate (d). Pour the liquid polymer therein and crosslink only about 1 hour at 50 ° C. (e), and then perform the photolithography process on the semi-crosslinked semi-liquid polymer once more (f). 2 (f) to remove the polymer of a specific portion by etching (piranian liquid (sulfuric acid: nitric acid = 3: 1) or aqua regia (sulfuric acid: hydrogen peroxide = 10: 1) and the like to the portion where the photoresist film is removed ( g), the remaining photoresist film is removed (h).

The semi-crosslinked polymer thus formed is completely cured at 70 ° C. for 2 hours. When the crosslinked polymer is desorbed from the silicon substrate, hydrophilicity is formed on the surface through corona discharge and attached to a clean silicon substrate to form a silicon substrate that exposes only a certain shape, thereby depositing only a desired portion of the solution during chemical CNT deposition. have.

According to the above, in forming a pattern, it is most important to form a certain shape. Another method is to place a certain shape stamp on a silicon substrate and pour a liquid polymer to harden it. Only a fraction can be removed in a physical way. In this way, a polymer mask may be formed.

In the case of biochips using existing CNTs, electrical and optical results were measured by growing CNTs at a predetermined portion, but the present invention has the advantage of attaching or depositing CNTs at desired positions.

As described above, in order to electrically detect the biomaterial attached to the substrate on which the CNTs are arranged, the liquid phase should be maintained. In this case, the necessary top plate should have a space to contain a fluid of several mm to several μm. As a substrate that can be used herein, various polymer materials such as polydimethylsiloxane (PDMS), polymetbylmethacrylate (PMMA), polycarbonate (PC), polyethylene (PE), polypropylene (PP), and polystyrene (PS) may be used. .

In the present invention, the CNTs may be connected to a power source through at least one conductive nanowires so that each electric charge can be applied, wherein the conductive nanowires may be formed as a single atom using conventional techniques (Science, 275: 1896-97,1997), a conductive pattern may be formed, and then a conductive wire may be deposited using ion implantation or sputtering.

3. Preparation of Thiol Functional Group (-SH) on Solid Substrate

In the present invention, a method of forming a polymer or photoresist pattern on a substrate such as glass, silicon wafer, plastic, or the like, and then fixing the aminoalkyloxysilane to the surface by using the pattern as a mask, exposing an amino group to the surface of the substrate. . It is preferable to use aminopropyl triethoxysilane as said aminoalkyloxysilane.

In order to expose the thiol functional group on the surface to which the amino group is fixed, the amino group is a thiol such as HOOC-R ₂ -SH where R ₂ is C _1-20 saturated hydrocarbons, unsaturated hydrocarbons or aromatic organic groups It is linked by an amide bond to a carboxyl functional group of a chemical having a functional group and a carboxyl functional group at the same time. As a result, a structure of a 'substrate-CONH-R ₂ -SH' form in which a thiol group is exposed on the substrate surface is formed.

At this time, it is preferable to use DIEA, TMP, NMI, etc. as a base, such as DCC, HATU, HBTU, HAPyU, HAMDU, HBMDU as a coupling agent of the amide bond. Moreover, when using water as a solvent, it is preferable to use EDC as a coupling agent, and NHS, NHSS etc. as a coupling aid.

4. A method of laminating CNTs on a substrate to form a pattern or film

First, gold-plated CNTs (Au-CNT-Au) are bound to a substrate (substrate-CONH-R ₂ -SH) to which a thiol functional group is exposed. At this time, between the gold crystals dotted with a thiol functional group and the CNT of the substrate surface Au-S link is formed by the CNT is bonded onto the substrate, the substrate _{-CONH-R 2 -S-Au-} CNT-Au ' type of structure Formed (FIG. 3A).

Next, a gold intercalated on the CNT selectively attached to the substrate is reacted with a chemical represented by HS-R ₃ -SH, which is a linker having a double thiol functional group, and the gold-plated conductive CNT is reacted with one of the other linkers. React with the side thiol functional group. This reaction forms a structure of the form 'substrate- [CONH-R ₂ -S-Au-CNT-Au-SR ₃ -S-Au-CNT-Au' (FIG. 3B).

Next, the chemical reaction between the conductive CNT interspersed with gold and the chemical compound having the double thiol functional group is repeatedly performed to increase the surface density of the conductive CNT on the surface. Finally, a conductive CNT pattern or conductive CNT film having a structure of 'substrate- [CONH-R ₂ -S-Au-CNT-Au- (SR ₃ -S-Au-CNT-Au) p] q' is formed ( 3C-3E). Where p and q are one or more natural numbers.

5. How to bind bioreceptors to gold-plated conductive CNTs

The bioreceptor is a substance that binds to or reacts with the target biomaterial, and a substance that serves as a probe capable of detecting the binding or reaction is preferable. Such bioreceptors include nucleic acids, proteins, peptides, amino acids, ligands, enzyme substrates, cofactors, and the like. In the present invention, a target biomaterial is a substance that can serve as a target detected by binding to or reacting with a receptor, and includes a protein, nucleic acid, or other biomolecule.

4 is a schematic diagram showing the selective interaction of various kinds of target biomaterials after the attachment of various receptors having functional groups that bind or react with gold to the surface of the CNTs interspersed with gold nanoparticles. It is preferable to contain a thiol group as a functional group which reacts with a gold nanocrystal. In FIG. 4, 1 and 2 represent bioreceptors capable of reacting with the target biomaterial, and 4 represents target biomaterials capable of reacting with the bioreceptor. 3 represents an oligonucleotide in a bioreceptor, 5 represents a complementary nucleic acid capable of hybridizing with the oligonucleotide immobilized on a metal of a conductive CNT, and 6 represents a general biomaterial that is not reactive.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention in more detail, it will be apparent to those skilled in the art that the scope of the present invention is not limited to these examples.

Example: Preparation of CNTs dotted with Au

After cutting single walled carbon nanotubes (SWNTs) using strong acids, CNTs containing carboxyl functional groups were subjected to redox reactions in a two-phase liquid-liquid system. CNTs were dotted with gold nanoparticles (FIG. 1).

First, with the aid of the coupling agent DCC in an ethanol solvent, a linker (2-aminoethanethiol) having an amino (-NH ₂ ) functional group and a thiol (-SH) functional group at the same time for about 24 hours at room temperature with CNT having the carboxyl functional group Stirred. Gold nucleation sites were formed by Au-S chemical bonding at the end and side bond positions of CNTs.

25 ml of a pale yellow 0.01% gold colloidal solution was placed in a glass reactor, and then 16.5 ml of 0.01665 mmol N (C ₈ H ₁₇ ) ₄ Br (toluene) solution was slowly added while rapidly stirring the solution. In this reaction, phase separation of water and toluene occurred, and the mixed solution was stirred very quickly until all of the color of the lower water portion disappeared. 2 mg of CNT formed with the thiol group was dispersed in 10 ml of toluene, and then slowly added to the upper toluene organic phase. Then 20.5 ml of 0.0825 mmol NaBH ₄ (water) solution was added with slow stirring. The reaction mixture was stirred rapidly at room temperature for 20 hours and then the toluene organic phase was separated from the aqueous phase using a separatory funnel. The separated organic phase was filtered using a polyvinylidenefluoride (PVDF) membrane filter having a pore size of 100 nm, in which toluene and ethanol were added several times.

The filtered sample was placed in tertiary distilled water and dispersed using ultrasonic waves, and the dispersion was centrifuged at 2000 rpm for 60 minutes. After removing the supernatant, the sample was again filtered using a membrane filter, and the finally obtained sample was vacuum dried.

The CNTs interspersed with gold crystals prepared by the above method were analyzed by a transmission electron microscope (TEM) and an X-ray photoelectron spectroscope (XPS). FIG. 5 (a) is a TEM image of CNTs interspersed with gold crystals obtained by forming a thiol group (-SH) on CNTs and then reacting gold colloids, and FIG. 5 (b) shows a thiol group (-SH). TEM image of CNTs which reacted with uncollated CNTs with gold colloids. From the analysis photograph, it can be seen that the gold crystals formed in the CNT having a thiol group are more scattered on the side than the terminal portion of the CNT, and the gold crystals were not interspersed in the CNT without the thiol group.

FIG. 6 is an enlarged HR-TEM photograph of FIG. 5. The regular d-spacing of the lattice measured in the photograph was 2.36 ± 0.02 Hz. This is in close agreement with the literature values (2.355 ms) for the {111} plane of gold (Powder Diffraction Data File 38-1364, Inorganic Phases, JCPDS International Center for Diffraction Data, Swathmore, PA, 199).

The oxidation state of gold crystals interspersed with CNTs was also confirmed by XPS. 7 is an XPS doublet spectrum for gold crystals interspersed with CNTs. The double peak binding energies of Au are 4f _5/2 (87.9 eV) and Au 4f _7/2 (84.2 eV), respectively. It is a value that corresponds to the reduced state of the gold (Au ^0). From this, it was found that most of the gold crystals scattered on the CNT surface were reduced gold crystals, not colloidal state.

As described in detail above, the present invention has the effect of providing a conductive CNT pattern and a method for producing a conductive CNT pattern or a CNT film laminated with the conductive CNT on a substrate interspersed with metal. The conductive CNTs and their patterns according to the present invention are expected to have great applicability to biosensors.

Claims (17)

Method for producing a conductive CNT interspersed with metal, characterized in that it comprises the following steps: (a) providing a CNT having a carboxyl group; (b) combining the carboxyl group of the CNT with an amino group of a chemical compound having an amino group and a thiol group at the same time to obtain a thiol group-modified CNT; And (c) bonding a metal to the thiol group of the CNT modified with the thiol group obtained in the step. The method of claim 1 wherein step (a) comprises treating the CNT with an acid. The method of claim 1, wherein step (c) comprises reacting the metal nanoparticles or colloid with CNT modified with a thiol group, followed by reduction. The method of claim 1 or 3, wherein the metal is gold (Au). The method of claim 1, wherein the chemical having an amino group and a thiol group at the same time is NH ₂ -R ₁ -SH Wherein R ₁ is a C _1-20 saturated hydrocarbon, unsaturated hydrocarbon or aromatic organic group. A conductive CNT prepared by the method of claim 5 and interspersed with a metal having the form of CNT- (CONH-R ₁ -SM) r, wherein M represents a metal, r is one or more natural numbers, and R ₁ is As defined in claim 4). The conductive CNTs of claim 6 wherein M is gold (Au). Method for producing a conductive CNT pattern characterized in that it comprises the following steps: (a) providing a substrate having a thiol group exposed on its surface; (b) bonding a metal of the conductive CNT of claim 6 to a thiol group on the substrate surface; And (c) stacking the conductive CNT by bonding the conductive CNT of claim 6 to the conductive CNT attached to the substrate. Method for producing a CNT film, comprising the following steps: (a) providing a substrate having a thiol group exposed on its surface; (b) bonding a metal of the conductive CNT of claim 6 to a thiol group on the substrate surface; (c) depositing a conductive CNT by bonding the conductive CNT of claim 6 to the conductive CNT attached to the substrate; And (d) repeating step (c) to increase the density of the conductive CNT. 10. The method according to claim 8 or 9, wherein step (a) exposes an amino functional group to the surface of the substrate on which the CNTs are to be deposited, and then is treated with a chemical having both a carboxyl group and a thiol group, thereby treating the amino groups on the substrate with the chemicals. To form an amide bond between the carboxyl groups. The method of claim 10, wherein the chemical having a carboxyl group and a thiol group at the same time is HOOC-R ₂ -SH (wherein R ₂ is a C _1-20 saturated hydrocarbons, unsaturated hydrocarbons or aromatic organic groups), characterized in that How to. The method of claim 10 wherein the substrate having amino functional groups exposed to the surface is obtained by treating the substrate with aminoalkyloxysilane. 10. The method of claim 8 or 9, wherein step (c) uses a linker having a double thiol functional group. 14. A method according to claim 13, wherein the linker having a double thiol functional group is a chemical represented by HS-R ₃ -SH, wherein R ₃ is C _1-20 saturated hydrocarbons, unsaturated hydrocarbons or aromatic oils. Device). 10. The method according to claim 8 or 9, wherein the substrate is formed with a photoresist or polymer pattern for attaching the conductive CNT to a desired position. 10. The method of claim 8 or 9, wherein the substrate is selected from the group consisting of glass, silicon, fused silica, plastic and PDMS. Prepared by the method of claim 9, Conductive CNT film having the structure of substrate- [CONH-R ₂ -S-Au-CNT-Au- (SR ₃ -S-Au-CNT-Au) p] q, where p and q are one or more natural numbers and R ₂ and R ₃ are C _1-20 saturated hydrocarbons, unsaturated hydrocarbons or aromatic organic groups).