• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.49 no.12
• /
• pp.649-653
• /
• 2000

We have grown carbon nanotubes by thermal chemical vapor deposition of $C_{2}H_{2}$ on catalytic metal deposited on silicon oxide substrates. Highly purified carbon nanotubes are uniformly grown on a large area of the silicon oxide substrates. It is observed that surface modification of catalytic metals deposited on substrates by either etching with dipping in a HF solution and/or $NH_{3}$ pretreatment is a crucial step for the nanotube growth prior to the reaction of $C_{2}H_{2}$ gas. The diameters of carbon naotubes could be controlled by applying the different catalytic metals.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.11a
• /
• pp.123-123
• /
• 2003

나노튜브는 반도체 재료로서 뿐만 아니라 다른 분야로까지 다양한 응용범위를 가진 물질로서 기존에는 주의 탄소를 사용하여 제작, 사용되어지고 있으나 게이트옥사이드(Gate Oxide) 물질인 지르코니아(ZrO$_2$), 타이타니아(TiO2$_2$) 등을 이용한 나노튜브는 많이 제작되어지고 있지 못하다. 따라서 보다 나은 성질을 갖는 물질로서 나노튜브를 제작할 시 반도체 재료에서의 고집적화를 통해 좋은 성질을 갖게 할 수 있으며 여러 분야로까지 확대가 가능한 재료를 사용하여 광학 및 환경분야 등 응용범위를 넓힐 수 있다. 본 실험은 나노튜브 제작에 있어서 템플레이트의 구멍 내부를 ALD 기술을 이용하여 균일한 두께를 갖는 금속 산화물층을 성장시킨 후 템플레이트 재료의 식각을 통해 금속산화물 나노튜브가 남아있게 하여 제작하는 방법이다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.26 no.10
• /
• pp.741-744
• /
• 2013

In this study, we fabricated anodic aluminum oxide (AAO) membrane by two step anodizing process for pH detection. The structural properties were observed by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). Electrochemical measurements of the pH sensor have been performed in capacitance-voltage (C-V) and drift rates. The characterization of AAO membrane exhibited high sensitivity (99.1 mV/pH) at second anodizing time of 4 min.

• Macromolecular Research
• /
• v.17 no.12
• /
• pp.995-1002
• /
• 2009

Luminescent polynorbornene (PNB)/quantum dot (CdSe@ZnS; QD) composite nanorods and nanotubes were successfully prepared using anodic aluminum oxide (AAO) membranes of various pore sizes as templates. To protect QDs with high quantum yield from quenching during the phosphoric acid treatment used to remove the AAO templates, chemically stable and optically clear norbornene-maleic anhydride copolymers (P(NB-r-MA)) were employed as a capping agent for QDs. The amine-terminated QDs reacted with maleic anhydride moieties in P(NB-r-MA) to form PNB-grafted QDs. The chemical- and photo-stability of QDs encapsulated with PNB copolymers were investigated by photoluminescence (PL) spectroscopy. By varying the pore size of the AAO templates from 40 to 380 urn, PNB/QD composite nanorods or nanotubes were obtained with a good dispersion of QDs in the PNB matrix.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07b
• /
• pp.1530-1533
• /
• 2005

We investigated under-gate type carbon nanotube field emitter arrays (FEAs) for back light unit (BLU) in liquid crystal display (LCD). Gate oxide was formed by wet etching of ITO coated glass substrate instead of depositing $SiO_2$ on the glass substrate. Wet etching is easer and simpler than depositing and etching of thick gate oxide to isolate the gate metal from cathode electrode in triode. Field emission characteristic s of triode structure were measured. The maximum current density of 92.5 ${\mu}A/cm^2$ was when the gate and anode voltage was 95 and 2500 V, respectively at the anode-cathode spacing of 1500 ${\mu}m$.

• Journal of Electrochemical Science and Technology
• /
• v.11 no.4
• /
• pp.399-405
• /
• 2020

Hollow copper oxide/multi-walled carbon nanotubes (CuO/MWCNT) composites were fabricated via an optimized infiltration-reduction-oxidation method, which is more facile and easy to control. The crystalline structure and morphology were characterized by X-ray diffraction (XRD), and transmission electron microscopy (TEM). The as-prepared CuO/MWCNT composites deliver an initial capacity of 612.3 mAh·g^-1 and with 80% capacity retention (488.2 mAh·g^-1) after 100 cycles at a current rate of 0.2 A·g^-1. The enhanced electrochemical performance is ascribed to the better electrical conductivity of MWCNT, the hollow structure of CuO particles, and the flexible structure of the CuO/MWCNT composites.

• Carbon letters
• /
• v.16 no.4
• /
• pp.223-232
• /
• 2015

This review presents current progress in the preparation methods of liquid crystalline nano-carbon materials and the liquid crystalline spinning method for producing nano-carbon fibers. In particular, we focus on the fabrication of liquid crystalline carbon nanotubes by spinning from superacids, and the continuous production of macroscopic fiber from liquid crystalline graphene oxide.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.08a
• /
• pp.263-263
• /
• 2010

실제 옷처럼 입는 컴퓨터를 구현하거나 복잡하고 움직임이 많은 사람의 장기 등 생체에 이식 가능한 정보 전자 소자를 개발하려는 시도가 많이 이루어지고 있다. 현재는 기존의 반도체 공정과 실리콘 소재를 기반으로 연구 결과가 보고되고 있는데, 이는 소자 제작에 있어서 높은 공정 온도 등으로 인해 응용성이 제한되는 상황이다. 우리는 metal oxide 나노선과 단일벽 탄소나노튜브 (SWCNT)를 성장하여 각각 슬라이딩 전이법과 thermal tape 전이법을 이용하여 원하는 기판에 전이하고 소자를 제작하였다. metal oxide 나노선은 슬라이딩 전이를 통해 정렬된 상태로 패턴을 제작하였으며, SWCNT는 density 제어와 채널 크기 조정을 통해 반도체성 채널을 유도하여 소자 특성을 확보하였다. 또한 각 나노선의 전계효과소자와 SWCNT로 구성된 PMOS inverter를 유연한 고분자 필름기판위에 구현하고, 이를 스트레칭이 가능한 스테이지를 이용해 strain 대비 전기특성 변화를 분석하였다. 유연성이 좋은 나노선/나노튜브로 제작된 해당 소자는 전체 소자가 스트레칭이 가능할 수 있게 연결구조를 디자인하여 수십% 의 stain에도 각각의 전기특성이 유지되었다. 이처럼 스트레칭이 가능한 1차원 나노소재 소자는 그 유연성을 바탕으로 입는 옷처럼 구겨지거나 늘여지게 되는 다양한 스트레칭 상황에도 특성이 보장되어 미래 정보전자소자로 많은 응용이 가능할 것으로 예상된다.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.12
• /
• pp.1827-1831
• /
• 2003

Field emission of carbon nanotubes (CNTs) fabricated by disproportionation of CO has been studied. CNTs fabricated on well-ordered Co nanowire arrays formed on the porous anodic aluminum oxide templates were well graphitized, uniform in diameter and aligned vertically with respect to the plane of the template, and showed a good field emission property. Very uniform emissions were observed from the CNTs fabricated at relatively low temperature, $500-600^{\circ}C$. Low fabrication temperature such as $500^{\circ}C$ could make it possible to fabricate CNTs on soda lime glass, a low-cost substrate, for display panel.

• Ceramist
• /
• v.21 no.1
• /
• pp.12-23
• /
• 2018

As the flexible displays have been considered as a breakthrough to make a new electronics category, transparent electrodes have also confronted with an emerging issue, i.e., they also need to be mechanically flexible. For this to be made possible, a transparent electrode capable of withstanding large amounts of strain must be developed. Indium tin oxide (ITO) has been one of the most widely adopted transparent electrodes for displays and other transparent electronics, mainly supported by its high electrical conductivity and optical transparency. However, its brittle nature has forced the display industry to search for other alternatives. Recently, advances in nano-material researches have opened the door for various transparent conductive materials, which include carbon nanotube, graphene, Ag and Cu nanowire, and printable metal grids. Here we reviewed recently-published research works introducing flexible displays, all of which are employing the novel candidates for a conducting material.