• 한국표면공학회지
• /
• 제41권3호
• /
• pp.102-108
• /
• 2008

In this paper, the LiF and polymer thin film as passivation layer have been evaporated on green OLED devices. HDPE, polyacenaphthylene, polytetrafluoroethylene, poly(2,6-dimethyl-1,4-pheneylene oxide), poly sulfone and poly(dimer-acid-co-alkyl poly-amine) have been used as polymer materials. The optical transmittance of evaporated polymer thin film was very good as an above 90% in visible range. The morphology of polymer thin film was measured by AFM. As a result of the measurement average roughness($R_a$) value of the polysulfone was very low as 2.2 nm. The green OLED devices with a structure of ITO/HIL/HTL/EML/Buffer/Al in series of various passivation films were fabricated and analyzed. It was observed that an OLED device with LiF as first passivation film has shown the good electrical and optical property, and all kind of polymer films did not influence on the I-V-L characteristics and the life time of OLED devices. Therefore, we found that polymer layer played a key role as a buffer layer between the inorganic passivation layers to relieve the stress of the inorganic layers.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
• /
• pp.504-505
• /
• 2005

In this report, we demonstrate a high performance polymer thin-film transistor fabricated on a paper substrate. As a water barrier layer, parylene was coated on the paper substrate by using vacuum deposition process. Using poly (3-hexylthiophene) as an active layer, a polymer thin-film transistor with field-effect of up to 0.086 $cm^2/V{\cdot}s$ and on/off ratio of $10^4$ was achieved. The fabrication of polymer thin-film transistor built on a cheap paper substrate is expected to open a channel for future applications in flexible and disposable electronics with extremely low-cost.

• 한국고분자학회:학술대회논문집
• /
• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
• /
• pp.201-201
• /
• 2006

In this study the glass transition temperature in thin polymer films has been studied. Ellipsometry has been used to measure $T_{g}$ of thin film as a function of film thickness. Empirical equation has been proposed to fit the measured $T_{g}$ pattern with thickness. Also, a continuous multilayer model was proposed and derived to describe the effect of surface on the observed $T_{g}$ reduction in thin films, and the depth-dependent $T_{g}$ profile was obtained. These results showed that $T_{g}$ at the top surface was much lower than the bulk $T_{g}$ and gradually approached the bulk $T_{g}$ with increasing distance from the edge of the film. The model and equation were modified to apply for the polymer coated on the strongly favorable substrate and the freely standing film.

• Macromolecular Research
• /
• 제9권1호
• /
• pp.1-19
• /
• 2001

Poly(p-phenylene pyromellitimide) and poly(4,4'-biphenylene pyromellitimide) are representatives of fully rod-like polyimides. Their structure and properties in thin films are reviewed. The polymers exhibit some excellent properties such as high molecular packing coefficient, high mechanical modulus, and low thermal expansion coefficient, and low interfacial stress, so that they are very attractive to both industry and academia. However, these polymers are very brittle and thus practically useless. Some chemical modifications to improve such drawback with a little sacrifice of the high modulus are described: i) incorporation of short side groups into the polymer backbone and ii) insertion of proper linkages into the polymer backbone.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
• /
• pp.1564-1567
• /
• 2008

We demonstrate here a self-aligned printing approach that allows downscaling of printed organic thin-film transistors to channel lengths of 100 - 400 nm. A perfected down-scaled polymer transistors (L= 200 nm) showing high transition frequency over 1.5 Mhz were realized with thin polymer dielectrics, controlling contact resistance, and minimizing overlap capacitance via self-aligned gate configuration.

• 한국전기전자재료학회논문지
• /
• 제34권1호
• /
• pp.16-20
• /
• 2021

In this study, we tried finding new materials to improve the stain resistance properties of polymer insulating materials. Using the filtered vacuum arc source (FVAS) with a graphite target source, DLC thin films were deposited on silicon and polymer insulator substrates depending on their thickness to confirm the surface properties, physical properties, and structural properties of the thin films. Subsequently, the possibility of using a DLC thin film as a protective coating material for polymer insulators was confirmed. DLC thin films manufactured in accordance with the thickness of various thin films exhibited a very smooth and uniform surface. As the thin film thickness increased, the surface roughness value decreased and the contact angle value increased. In addition, the elastic modulus and hardness of the DLC thin film slightly increased, and the maximum values of elastic modulus and hardness were 214.5 GPa and 19.8 GPa, respectively. In addition, the DLC thin film showed a very low leakage current value, thereby exhibiting electrical insulation properties.

• 한국입자에어로졸학회지
• /
• 제6권2호
• /
• pp.61-67
• /
• 2010

In this paper, we describe a new method to form polymer thin films, in which carbon nanotubes (CNTs) are homogeneously distributed so that they can strengthen the mechanical property of resulting polymer film. To do so, we first homogeneously mixed CNTs with polymer in a DMF solvent. With the assistance of ultrasonic nebulizer, the polymer/CNT solution was then aerosolized into micro-sized droplets and finally turned into solidified polymer/CNT composite particles by gas-phase drying process. As the results of SEM and TEM analysis, CNTs were found to be homogeneously immobilized in the polymer matrix particles due to rapid drying process in the gas phase. For comparison purpose, (i) the polymer/CNTs composite particles prepared by aerosol processing method and (ii) polymer/CNTs sheets prepared by simple solution-evaporation method were employed to form polymer/CNTs composite thin films using a hot press. As the result, the aerosol processing of composite particles was found to be a much more effective method to form homogeneously distributed-CNTs in the polymer matrix thin film.

• 조명전기설비학회논문지
• /
• 제25권12호
• /
• pp.48-53
• /
• 2011

Polymer thin films were prepared by capacitively coupled plasma polymerization process for application of gate insulator. The polymer thin films revealed to form polymer layers with original properties of the monomer. Among the plasma polymer thin films, the styrene polymer having large number of phenyl sites revealed higher dielectric constant of k=3.7 than that of conventional polymer. The plasma polymerized styrene thin film revealed no hysteresis characteristics and low leakage current density of $1{\times}10^{-8}[Acm^{-2}]$ at field strength of $1[MVcm^{-1}]$, which measured by I-V and C-V measurements using MIM and MIS devices.

• 한국고분자학회:학술대회논문집
• /
• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
• /
• pp.293-293
• /
• 2006

Self-assembled nanostructures of block copolymer thin films have gathered significant attention due to their potential applications as templates for nanofabrication. However the lack of a robust strategy to control the structure formation in thin film geometries has been considered a major obstacle for the practical application. In this presentation 'epitaxial self-assembly' will be introduced as a successful strategy to control the self-assembled nanostructure of block copolymer. Chemically patterned surfaces prepared by advanced lithographic techniques successfully registered nanodomains in block copolymer thin film without any single defect over an arbitrarily large area.

• Macromolecular Research
• /
• 제15권3호
• /
• pp.211-215
• /
• 2007

Hybrid thin film nanostructures composed of metal nanoparticles (NPs) and self-assembled polymer films with different spatial distributions of NPs were analyzed by optical waveguide spectroscopy (OWS). Specifically, the dielectric constants were calculated using effective medium theory for the incorporation of 1 vol% Au NP into the block copolymer (BCP) films having a cylindrical nanodomain morphology. Three cases were considered: uniform distribution of NPs in the film; selective distribution of NPs only in the cylindrical domains; and segregation of NPs to the center of the cylindrical domains. The optical waveguide spectra derived from the calculated dielectric constants demonstrate the feasibility of experimentally distinguishing the composite nanostructures with different inner morphologies in the hybrid metal NP-BCP nanostructures, by the measurement of the dielectric constants using OWS.