• Transactions on Electrical and Electronic Materials
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• 제4권4호
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• pp.26-29
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• 2003

To discover electrical properties of individual single wall nanotube(SWNT), a number of SWNT-based tubeFETs have been fabricated. The device consists of a single semiconducting SWNT on an insulating substrate, contacted at each end by metal electrodes. It presents high transconductances, and charge storage phenomenon, which is the operations of injecting electrons from the nanotube channel of a tubeFET into charge traps on the surface of the $SiO_2$ gate dielectric, thus shifting the threshold voltage. This phenomenon can be repeated many times, and maintained for the hundreds of seconds at room temperature. We will report this phenomenon as the memory effects of the SWNT, and attempt to use this property for the memory device.

• 한국정밀공학회지
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• 제24권6호
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• pp.113-120
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• 2007

Chemical vapor deposition (CVD) is one of the various synthesis methods that have been employed for carbon nanotube (CNT) growth. In particular, Ren et al reported that large areas of vertically aligned multi-wall carbon nanotubes could be grown using a direct current (dc) PECVD system. The synthesis of CNT requires a metal catalyst layer, etchant gas, and a carbon source. In this work, the substrates consists of Si wafers with Ni-deposited film. Ammonia $NH_3$) and acetylene ($C_2H_2$) were used as the etchant gases and carbon source, respectively. Pretreated conditions had an influence on vertical growth and density of CNTs. And patterned growth of CNTs could be achieved by lithographical defining the Ni catalyst prior to growth. The length of single CNT was increased as niclel dot size increased, but the growth rate was reduced when nickel dot size was more than 200 nm due to the synthesis of several CNTs on single Ni dot. The morphology of the carbon nanotubes by TEM showed that vertical CNTs were multi-wall and tip-type growth mode structure in which a Ni cap was at the end of the CNT.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.236-237
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• 2007

A single-wall carbon nanotube (SWNT) transparent conductive film (TCF) was fabricated using a simple inkjet printing method. The TCF could be selectively patterned by controlling the dot size to diameters as small as 34${\mu}m$. In thisrepeatable and scalable process, we achieved 71% film transmittance and a resistance of 900 ohm/sq sheet with an excellent uniformity, about $\pm$5% deviation overall. Inkjet printing of SWNT is substrate friendly and the TCF is printed on a flexible substrate. This method of fabrication using direct printing permits mass production of TCF in a large area process, reducing processing steps and yielding low-cost TCF fabrications on a designated area using simple printing.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.275-278
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• 2004

Electro-Active Paper (EAPap) is attractive for EAP actuator due to its merit in terms of light weight, dry condition, large displacement output, low actuation voltage and low power consumption. The EAPap is based on cellulose paper, and is shown to involve primarily transport of ions in response to an external electric field. This actuating mechanism is similar to conductive polymer based actuators. For performance improvement of EAPap, hybrid actuators are tried. The actuators based on cellulose paper attached conducting polypyrrole, polyaniline and single wall carbon nanotube/polyaniline(emeraldine base) have been achieved by Electro chemical deposition and mechanical deposition of the polymers onto cellulose paper.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.700-702
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• 2004

The dependence of environmental gases such as Ar, $O_2$ on the emission current from carbon nanotube emitters was examined in this study. Based on our experiments, the current density is decreased in single-wall carbon nanotubes (SWNTs), but is increased in multi-wall carbon nanotubes (MWNTs) as the vacuum level decreases from $10^{-7}$ Torr to $10^{-4}$ Torr by the inflow purging gases. The current density subsequently recovered as the vacuum level increased to $10^{-7}$ Torr when gas inflow stopped. From those results, we conclude that the MWNTs have completely different degradation characteristics in comparison to SWNTs excluding the effect of binder materials.

• Composites Research
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• 제33권1호
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• pp.7-12
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• 2020

지난 10년간 효율적인 방열 재료 개발을 위해 유망한 매트릭스로서 액정 에폭시 수지(Liquid crystalline epoxy, LCER)는 많은 주목을 받아 왔다. 본 연구에서는 LECR중에서 대표적인 4,4-diglycidyloxybiphenyl (DP) 에폭시를 이용한 고분자/SWCNT 복합체의 합성과 제조 및 특성 분석을 포함한 포괄적인 연구를 제시한다. 복합 재료의 열전도 특성을 확인해보기 위해 에폭시 수지와 충전제인 단일벽 탄소나노튜브(Single-wall carbon nanotube, SWCNT)로 구성된 복합체 샘플이 준비되었다. 특히 DP 복합체는, LCER의 고도로 정렬 된 미세 구조로 인해 동일한 필러를 사용하는 상업용 에폭시의 복합체에 비해 높은 열 전도성을 보였다. 또한, DP 복합체의 열전도도는 충전제의 양을 조절하여 제어할 수 있으며, 특히 SWCNT의 함량이 50 wt%인 DP 복합체는 열전도도는 2.008 W/mK로 가장 높은 열전도도를 나타내었다.

• 대한기계학회논문집B
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• 제33권10호
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• pp.773-777
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• 2009

In this study, the strain sensing characteristics of single-wall carbon nanotubes(SWCNTs) networks were investigated to develop a film sensor for strain sensing. The SWCNTs film are formed on flexible substrates of poly(ethylene terephthalate) (PET) using spray process. In this manner we could control the transparency and obtain excellent uniformity of the networked SWCNT film. The carbon nanotube film is isotropic due to randomly oriented bundles of SWCNTs. Using experimental results it is shown that there is a nearly linear change in resistance across the film when it is subjected to tensile stress. The results presented in this study indicate the potential of such films for high sensitive transparent strain sensors on macro scale.

• 반도체디스플레이기술학회지
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• 제4권3호
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• pp.11-15
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• 2005

This paper shows that carbon nanotubes can be applied to a nanopipette. Nano space in atomic force microscope multi wall carbon nanotube tips is filled with molecules and atoms with charges and then, the tips can be applied to nanopipette when the encapsulated media flow off under applying electrostatic farces. Since the nano space inside the tips can be refilled, the tips can be permanently used in ideal conditions of no chemical reaction and no mechanical deformation. Molecular dynamics simulations for nanopipette applications demonstrated the possibility of nano-lithography or single-metallofullerene-transistor array fabrication.

• Transactions on Electrical and Electronic Materials
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• 제9권4호
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• pp.169-172
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• 2008

We attempted to fabricate carbon nanotube field effect transistor (CNT-FET) using single walled carbon nanotube(SWNT) on the heavily doped Si substrate used as a bottom gate, source and drain electrode were fabricated bye-beam lithography on the 500 nm thick $SiO_2$ gate dielectric layer. We investigated electrical and physical properties of this CNT-FET using Scanning Probe Microscope(SPM) and conventional method based on tungsten probe tip technique. The gate length of CNT-FET was 600 nm and the diameter of identified SWNT was about 4 nm. We could observed gating effect and typical p-MOS property from the obtained $V_G-I_{DS}$ curve. The threshold voltage of CNT-FET is about -4.6V and transconductance is 47 nS. In the physical aspect, we could identified SWNT with phase mode of SPM which detecting phase shift by force gradient between cantilever tip and sample surface.

• Journal of Electrochemical Science and Technology
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• 제3권3호
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• pp.143-148
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• 2012

The unique effects of highly conductive conducting polymer/SWNT (single walled carbon nanotube) composite nanoparticles in electric double layer capacitors are studied for the enhancement of the adhesive properties, specific capacitance and power characteristics of the electrode. Because the conducting polymer/SWNT composite material, which is believed to act as a polymer binder, an active material for charge storage and a conducting agent, is well distributed on the activated carbon, greatly enhanced adhesion properties, cell capacitance and power characteristics were obtained.