• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1211-1212
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• 2013

• 통합자연과학논문집
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• 제2권1호
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• pp.13-17
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• 2009

A newly developed OTFT manufacturing process using the combination of self-assembly techniques and vapor phase polymerization method revealed that a thick $SiO_2$ dielectric layer (100~200 nm) is not well compatible with conducting polymer electrode, thereby resulting in still recognizable contact resistance, unstable $V_{th}$ and leaking off current. A couple of very recent studies showed that this issue may be solved by replacing such inorganic dielectric with a self-assembled monolayer or multilayer (organic) dielectric. Therefore, this short review introduces recent trends in the development of high performance thin film transistor consisting of both organic semiconductor and SAM dielectric.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1989년도 춘계학술대회 논문집
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• pp.63-65
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• 1989

Piezoelectric BaTiO$_3$-polymer composite were investigated for dielectric and piezoelectric properties with the barium titanate active particle size. Under the condition of the same density and ceramic volume ratio of composite, the dielectric and piezoelectric constant of composite are increasing as the ceramic particle size in composite are increasing. The surface layer model was quoted to explain these phenomena in our system and experimentally confirmed. The connectivity parameter of modified cube model of composite was calculated from the dielectric constant variation as their particle size. The connectivity parameter X and Y were 77.8% and 98.9% respectively. It means that the barium titanate particle distribution in composite nearly approach to the parallel mode. It was experimentally confirmed that the surface layer has low dielectric and nonferroelectric properties. Dielectric constant and thickness of surface layer were calculated from the equivalent circuit of composite.

• 폴리머
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• 제33권1호
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• pp.39-44
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• 2009

폴리페닐렌에테르[PPE, poly(phenylene ether)]를 기저수지로 사용하고, 가교제로 N,N'-m-phenylene-dimaleimide(PDMI), 난연제로 decabromodiphenylethane을 첨가하여 고분자 기판을 제작하였으며, 가교제와 난연제가 기판소재의 유전특성 등 물리적 특성에 미치는 영향을 고찰하였다. 개시제의 유무에 따른 PDMI의 열경화 특성을 DSC를 이용하여 분석하였으며, 이를 바탕으로 PPE-PDMI 테스트 조성을 설계하였다. 복합물 시트를 필름 코터로 성형한 후, 진공가압적층하여 테스트 기판을 제작하고, FDMI와 난연제의 함량에 따른 유전율, 유전손실, peel 강도, 납 내열성 및 난연성을 평가하였다. 유전율과 유전손실은 PDMI와 난연제의 함량에 따라 대체로 증가하는 경향을 나타내었으나, 납 내열성과 난연성은 개선된 결과를 나타내었다. Peel 강도는 PDMI가 10 wt% 이상 첨가되면 1 kN/m 이상의 높은 값을 나타내었지만, 난연제의 첨가량에 따라서는 소폭 감소하는 경향을 보였다. Gel content 측정결과로부터, PPE-PDMI의 반응 메카니즘은 semi-IPN 구조의 형성보다는 PPE와 PDMI의 crosslinking에 의한 망상구조 형성에 더 가까운 것으로 판단되었다. 최종적으로 1 GHz에서 유전율이 2.52$\sim$2.65, 유전손실이 0.002 미만으로 작은 고주파 대역용 고분자 복합체 기판소재를 얻을 수 있었다.

• E2M - 전기 전자와 첨단 소재
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• 제9권4호
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• pp.364-371
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• 1996

In this study, in order to investigate the applicability of IPN structure to epoxy resin which has been widely used as electrical and electronic insulating materials, DC dielectric breakdown properties and morphology were compared and analyzed according to variation of network structure, using the single network structure specimen formed of epoxy resin alone, interpenetrating polymer network specimen formed of epoxy resin/methacrylic acid resin, and interpenetrating polymer network specimen formed of epoxy resin/methacrylic acid resin/polyurethane resin. As results of the measunnent of DC dielectric breakdown strength at 50[.deg. C] and 130[>$^{\circ}C$], IPN specimen formed of epoxn, resin 100[phr] and methacrylic acid resin 35[phr] was the most excellent, and which corresponded to the SEM phenomena. The effect of IPN was more remarkable at high temperature region than at low temperature region. It is supposed that the defect of epoxy resin, dielectric breakdown strength is lowered remarkably at high temperature region, be complemented according to introducing IPN method.

• 폴리머
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• 제38권6호
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• pp.726-734
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• 2014

Three different types of additives, thiokol, epoxidized natural rubber (ENR) and epoxidized linseed oil (ELO), were dispersed in an epoxy matrix before being used in glass fiber (GF) composites, and their effects on the mechanical and dielectric properties of epoxy resin and glass fiber reinforced epoxy composites (GF/EP) were examined. The addition of each of 7 phr ENR, 9 phr ELO and 5 phr thiokol into the epoxy resin increased the fracture toughness significantly by 56.9, 43.1, and 80.0%, respectively, compared to the unmodified resin. The mode I interlaminar fracture toughness of the GF/EP at propagation was also improved by 26.9, 18.3 and 32.7% when each of 7 phr ENR, 9 phr ELO, and 5 phr thiokol, respectively, was dispersed in the epoxy matrix. Scanning electron microscopy showed that the additives reduced crack growth in the GF/EP, whereas their dielectric measurements showed that all these additives had no additional effect on the real permittivity and loss factor of the GF/EP.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.616-619
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• 2009

Color tracking behavior of in the fringe-field switching (FFS) mode using a liquid crystal with positive dielectric anisotropy has been studied. In the in-plane switching and vertical alignment devices, color chromaticity at normal direction changes from bluish to yellowish white linearly with increasing grey levels from dark to white state. Interestingly, abnormal behavior in color tracking is observed in FFS devices using a liquid crystal with positive dielectric anisotropy, that is, it changes from bluish to yellowish up to a certain middle grey level but turns over to bluish white with further increasing from a grey level to a fully white state. In this paper, we analyze this abnormal effect from the calculated and experimental results.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1200-1203
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• 2004

We investigated the molecular aligning capability of a polymer layer containing ceramic nanoparticles which can be used as a gate insulator of organic thin-film transistors (OTFTs). Because of the enhanced dielectric properties arising from the nanoparticles and molecular aligning properties of the polymer, the composite layer provides excellent mobility characteristics of the OTFTs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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• pp.13-16
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• 1994

The porous PZT was prepared from a mixture of PZT and polyvinylalcohol (PVA ) powders by BURPS( Burnedout Plastic Sphere) technique. The dielectric and piezoelectric properties of piezoceramic/polymer composites dependent on the PVA wt. % were evaluated. The density of PZT/polymer 3-3 composites were decreased almost linearly with increasing the PVA wt. %.

• 한국전기전자재료학회논문지
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• 제22권12호
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• pp.1009-1013
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• 2009

In this study, we have been synthesized the dielectric layer using pure organic and organic-inorganic hybrid precursor on flexible substrate for improving of the organic thin film transistors (OTFTs) and, design and fabrication of organic thin-film transistors (OTFTs) using small-molecule organic semiconductors with pentacene as the active layer with record device performance. In this work OTFT test structures fabricated on polymerized substrates were utilized to provide a convenient substrate, gate contact, and gate insulator for the processing and characterization of organic materials and their transistors. By an adhesion development between gate metal and PI substrate, a PI film was treated using $O_2$ and $N_2$ gas. The best peel strength of PI film is 109.07 gf/mm. Also, we have studied the electric characteristics of pentacene field-effect transistors with the polymer gate-dielectrics such as cyclohexane and hybrid (cyclohexane+TEOS). The transistors with cyclohexane gate-dielectric has higher field-effect mobility, $\mu_{FET}=0.84\;cm^2/v_s$, and smaller threshold voltage, $V_T=-6.8\;V$, compared with the transistor with hybrid gate-dielectric.