• Vacuum Magazine
• /
• v.3 no.1
• /
• pp.22-31
• /
• 2016

Although graphene has been considered as one of the promise materials for future logic devices due to extremely high mobility, its applications in electronics have been limited to a few cases such as a flexible interconnect, and RF devices. Furthermore, most of the studies on graphene devices reported unstable operations, claimed to be due to the poor quality of graphene. Nevertheless, recent studies showed that the electrical performance of graphene field effect transistor could be stabilized even with CVD graphene when well-established integration processes to control the interface of graphene were used. These results indicate that as in the case of silicon devices, a proper control of graphene interface is very important for the stable operation of graphene device as well as other 2D material based devices.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.629-632
• /
• 2008

Printed organic thin-film transistors (OTFTs) were used in the fabrication of a screen- printed gate, source and drain electrodes on flexible plastic substrates using silver pastes, a coated polyvinylphenol dielectrics, and jetted bis(triisopropyl-silylethynyl) pentacene (TIPS-pentacene) organic semiconductor. The OTFTs printed using screen printing and soluble processes made it was possible to fabricate a printed OTFT with a channel length as small as $13\;{\mu}m$ on plastic substrates; this was not possible using previous traditional printing techniques.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.25 no.7
• /
• pp.500-505
• /
• 2012

In this study, the influence of the intermolecular distance on the charge mobility in a pentacene thin-film was investigated. In order to increase the mobility which depends on the ${\pi}$-overlap between molecules, the intermolecular distance was shortened by compressive force along the conduction channel. Pentacene thin-film was fabricated on flexible substrates bent outward at different radii to stretch the gate dielectric surface and then the substrates were unbent, producing the compressive force to the film. The result showed that the mobility increased proportionally to the strain applied during the pentacene deposition and the molecular packing inside a grain was not optimal for the charge transport.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2010.05a
• /
• pp.25.1-25.1
• /
• 2010

본 연구에서는 절연막에 삽입시킨 실리콘 나노와이어 유연소자를 제작하고 그 소자의 전기적 특성을 분석하여 유연소자로서의 적합성을 평가하였다. 최근 반도체 및 디스플레이 등이 다양한 현장에 응용되면서 유연성을 이용한 소자의 필요성이 대두되고 있다. 이러한 요구를 바탕으로 나노와이어를 유연소자에 적용시키기 위하여 삽입방법을 이용하여 field-effect transistor(FET) 소자를 제작하였다. 유연소자의 기판으로는 polyimide(PI) 및 poly(ethylene 2,6 naphtahalate)(PEN)을 사용하였고, 절연막은 poly-4-vinylphenol(PVP)을 이용하였으며 이때, 나노와이어는 무전해 식각법으로 합성한 실리콘 나노와이어를 사용하였다. 이렇게 제작된 유연소자를 휨 상태 및 삽입된 정도에 따른 전기적 특성을 비교하였고 휨 테스트를 통하여 소자의 안정성을 분석하였다. 전기적 특성은 I-V 측정을 통하여 Ion/Ioff ratio, 이동도, subthreshold swing, threshold voltage값 등을 평가하였다.

• Korean Journal of Materials Research
• /
• v.17 no.7
• /
• pp.352-357
• /
• 2007

Since a pattern defects "repair" system using a diode pumped solid state laser for Flat Panel Display (FPD) was suggested, a lot of laser systems have been explored and developed for mass-production microfabrication process. A maskless lithography system using 405 nm violet laser and Digital Micromirror Device (DMD) has been developed for PDP and Liquid Crystal Display (LCD) Thin Film Transistor (TFT) photolithography process. In addition, a "Laser Direct Patterning" system for Indium Tin Oxide (ITO) for Plasma Display Panel(PDP) has been evaluated one of the best successful examples for laser application system which is applied for mass-production lines. The "heat" and "solvent" free laser microfabrications process will be widely used because the next-generation flat panel displays, Flexible Display and Organic Light Emitting Diode (OLED) should use plastic substrates and organic materials which are very difficult to process using traditional fabrication methods.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.158-158
• /
• 2011

A wide range of techniques for the direct-printing of functional materials have been developed for the fabrication of micro- and nanoscale structures and devices. Here we report a new direct patterning method, liquid bridge-mediated nanotransfer molding (LB-nTM), for the formation of two- or three-dimensional structures with feature sized as small as tens of nanometers over large areas up to 4". LB-nTM is based on the direct transfer of various materials from a mold to a substrate via a liquid bridge between them. The LB-nTM method was applied to the preparation of organic nanowire FETs on flexible substrates.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2018.06a
• /
• pp.50.1-50.1
• /
• 2018

산화물 반도체 기반 박막 트랜지스터가 국내에서 본격적으로 연구 개발 된 지 10년 만에 대면적 OLED TV에 적용되었다. 전기적인 신뢰성뿐만 아니라, 광학적 신뢰성도 검증되어, 앞으로 산업계에서 그 적용 확대가 기대되고 있는 상황이다. 그렇지만, 향후 큰 성장이 예상되는 고해상도 플렉시블 디스플레이에 적용 가능한 높은 수준의 전기적 특성뿐만 아니라, 저온공정도 만족시킬 수 있는 박막 트랜지스터 개발이 필요한 실정이다. 이러한 측면에서 LTPS, 유기물 박막 트랜지스터에 비해, 산화물 박막 트랜지스터는 250도 이하의 저온공정에서도 고이동도 및 고신뢰성을 확보할 수 있는 좋은 대안이 될 수 있을 것이다. 본 강연에서는 플렉시블 기판에 적용 가능한 산화물 박막 트랜지스터 기술 및 개발 동향에 대해 발표할 예정이다.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.543-544
• /
• 2006

Pentacene thin film transistors fabricated without photolithographic patterning were fabricated on the plastic substrates. Both the organic/inorganic thin films and metallic electrode were patterned by shifting the position of the shadow mask which accompanies the substrate throughout the deposition process. By using an optically transparent zirconium oxide ($ZrO_2$) as a gate insulator and octadecyltrimethoxysilane (OTMS) as an organic molecule for self-assembled monolayer (SAM) to increase the adhesion between the plastic substrate and gate insulator and the mobility with surface treatment, high-performance transistor with field effect mobility $.66\;cm^2$/V s and $I_{on}/I_{off}$>$10^5$ was formed on the plastic substrate. This technique will be applicable to all structure deposited at low temperature and suitable for an easy process for flexible display.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.64-66
• /
• 2009

We obtained high performance of n-type organic thin film transistors (OTFTs) using a solution process. N, N' bis-(octyl-)-dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDI-$8CN_2$) in ambient air. Low work function interlayer on source/drain is needed to enhance the electron injection to low LUMO level of n-type organic semiconductor. By using self-assembled monolayer (SAM) the field-effect mobility of 0.33 $cm^2$/Vs was achieved.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.267-270
• /
• 2007

Organic thin-film transistors (OTFTs) using organic semiconductors as an active layer are of interest for their use in low-cost, lightweight and flexible electronic products. Although the field-effect mobility of OTFTs is still lower than those of inorganic thin-film transistor, the advantages of easy manufacturing and processing make them suitable for selected applications. In this paper, we report the syntheses and characterization of new p-type OTFT materials.