• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.43-43
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• 2010

we have investigated the field emission characteristics of the CNT/TEOS hybrid thin films fabricated by a spray method. It is found that the CNT/TEOS hybrid emitters show high current density, low turn on field, and long-term emission stability compared to the CNT emitters. These efficient field emission characteristics of the CNT/TEOS hybrid emitters are attributed to the TEOS sol, acting as a protection layer of nanotube emitter by surrounding the nanotube tip as well as a binder material to enhance the adhesion of nanotube emitters to the substrate. Therefore, the CNT/TEOS hybrid emitters could be utilized as an alternative for the efficient and reliable field emitters.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.7
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• pp.594-598
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• 2008

The metal catalyst particles which there is as impurities on a tip part of carbon nanotube (CNT) are not good to apply it to a nano-electronic device. It was very important the opening of CNT-tip to fix a target bio material and a material to accept in CNT in a biosensor, so we performed $HNO_3$ wet etching to remove the metal catalyst particle which there was on a tip part of CNT grown up in the study and observed the opened CNT-tip with etching time. We synthesized the CNTs using a HF-PECVD method and choses the CNT length of 700 nm for the application of nano-electronic device such as a biosensor etc.. We observed the opened CNT-tip with wet etching times of $HNO_3$ (10, 30, 60 min). From the results, we observed that the CNT-tip was opened with the increase of wet etching time lively. In case of CNTs etched during 60 min, we confirmed that there was not the ratio of Ni included in CNTsI as catalyst. Conclusively, in the case of CNT etched for 60 minutes, it is completely good for application of a biosensor and, in addition, the metal-free CNTs will contribute to the application of other nanoelectronic devices.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.986-990
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• 2004

In this paper, we propose a method to estimate the actuating voltage of the nanotweezer made by manual assembly using carbon nanotube. The nanotweezer is composed of two CNT arms that are made by the multiwalled carbon nanotube and tungsten tip. Since the each CNT arm has the macro actuator, the nanotweezer can manipulate a large particle and it is possible to close and open the CNT arm repeatedly. The closing voltage, i.e., actuating voltage is calculated using the capacitance between the carbon nanotubes in CNT arm. We demonstrate the actuation of the nanotweezer using the voltage calculated with the electrostatic force.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.146-150
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• 2004

We researched carbon nanotube(CNT) cartridge as a CNT sample for the fabrication of nanotweezer which is composed of a couple of single CNT tip. Our CNT cartridge was made by dielectrophoretic methods, a kind of micromanipulation technique using electric field. Therein we intended to fabricate the CNT cartridge with just conventional function generators and a set of simple electrode. A knife edge and a flat metal electrode were employed as a couple of electrode, and these electrode pair faced each other with the gap. When the gap is filled with CNT suspension, we induced AC electric field into the gap. Then CNTs was attached on the sharp edge in knife edge by dielectrophoresis. This knife edge with attached CNTs is called as the CNT cartridge.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.2
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• pp.50-54
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• 2005

We report a simple, low cost, and reliable method for assembling a multi-walled nanotube (MWNT) to the end of a metal coated scanning probe microscopy (SPM) tip. By dropping the MWNT solution and applying an electric field between an SPM tip and an electrode, MWNTs which were dispersed into a dielectric solution were directly assembled onto the apex of the SPM tip due to the attraction by the dielectrophoretic force. The effective measurement of a MWNT -attached SPM tip was demonstrated by direct comparison with AFM images of a standard sample with a bare AFM tip.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.3
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• pp.13-18
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• 2002

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.161-161
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• 2004

AC 이중전기영동(AC electrophoresis)의 원리를 이용하여 탄소나노튜브 팁 제작용 탄소나노튜브 시편의 기초 실험을 수행하였다. 본 연구에서 사용한 방법은, 끝이 뽀족한 다수의 팁(tip)에 탄소나노튜브를 비교적 균일하게 부착시킬 수 있는 공정의 기반이 된다. 이것은 탄소나노튜브를 이용한 나노팁(nano-tip)이나 탄소나노튜브 나노그리퍼(nanogripper) 제작 공정에 균일성을 확보할 수 있는 중요한 방법으로 활용될 수 있다. 탄소나노튜브 시편의 제작을 위해, 끝단이 곡률반경이 50nm 정도인 텅스텐 팁과 직경 1.5mm, 깊이 1.5mm의 실린더형 금속전극을 사용했다.(중략)

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.43-43
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• 2003

Carbon nanotubes(CNTs) have many application points, which are field emission devices, composites, hydrogen storage, nanodevices, supercapacitor and secondary battery. The most promising application point is emitter tip mays of field emission devices. Furthermore, it may be also useful as a vacuum device for high frequency and high power. But, there are some obstacles to fabricate carbon nanotube field emission device. One is that CNTs grown by CVD method has weak adhesion with substrate and the other is non-uniform length of them. These problems are very crucial in aging property and reliability of device in the field emission.

• Journal of Powder Materials
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• v.15 no.3
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• pp.188-195
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• 2008

Carbon nanotube (CNT)/$Mg_2Ni$ composites were synthesized to enhance the hydrogen storage properties. The emphasis was made on the effect of different shortening methods of CNTs on the open-tip structure and the resulting properties. The use of open CNTs as a starting material resulted in an enhanced hydrogen properties of CNT/$Mg_2Ni$ composites. Among the employed methods for the shortening of CNTs, wet milling using ethanol was the most efficient, while ultrasonic acid treatment or thermal decomposition resulted in a less hydrogen storage capacity.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.61-62
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• 2022

Carbon nanotubes were used to secure high strength, high durability, and fracture toughness of cementitous composites.In this study, carbon nanotube dispersion solutions were prepared using commercial superplasticizers, such as polycarboxylate-ester and sodium naphthalene sulfonate with tip sonication. The solutions were used to prepare cement paste with MWCNT and The mechanical properties of the cement paste composite with MWCNT solutions were evaluated.