• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.661-664
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• 2004

In this paper, it was demonstrated that the organic thin film transistors with the organic gate insulators were fabricated by vapor deposition polymerization (VDP) processing. The configuration of OTFTs was a staggered-inverted top-contact structure and gate dielectric layer was deposited with 0.45 ${\mu}m$ thickness. In order to form polyimide as a gate insulator, VDP process was also introduced instead of spin-coating process. Polyimide film was respectively co-deposited with different materials. One was from a 4,4'-oxydiphthalic anhydride (ODPA) and 4, 4'-oxydianiline (ODA) and the other was from 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and ODA. And it was also cured at 150 $^{\circ}C$ for 1 hour followed by 200 $^{\circ}C$ for 1 hour. Electrical characteristics of the organic thin-film transistors were detailed comparisons between the ODPA-ODA and the 6FDA-ODA which were used as gate insulator.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.92-96
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• 2009

A new precursor [$Zr(acac)_{3}(H_{2}O)_{2}$] was synthesized by Sonochemical technique and used to deposit thin $ZrO_{2}$ film on quartz and ceramic substrate via ultrasonic aerosol assisted chemical vapour deposition (UAACVD) at 300 ${^{\circ}C}$ in oxygen environment followed by annealing of the sample for 2-3 minutes at 500 ${^{\circ}C}$ in nitrogen ambient. The molecular structure of the precursor determined by single crystal X-ray analysis revealed that the molecules are linked through intermolecular hydrogen bonds forming pseudo six and eight membered rings. DSC and TGA/FTIR techniques were used to determine thermal behavior and decomposition temperature of the precursor and nature of evolved gas products. The optical measurement of annealed $ZrO_{2}$ film with tetragonal phase shows optical energy band gap of 5.01 eV. The particle size, morphology, surface structure and composition of deposited films were investigated by XRD, SEM and EDX.

• 한국표면공학회지
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• 제36권1호
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• pp.9-13
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• 2003

Plasma polymerized organic thin films were deposited on Si(100), glass and metal substrates at $25∼100 ^{\circ}C$ using thiophene and toluene precursors by PECVD method. In order to compare physical and electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 30∼100 W and deposition temperature on both corrosion protection efficiency and physical properties were studied. We found that the corrosion protection efficiency ($P_{k}$), which is one of the important factors for corrosion protection in the interlayer dielectrics of microelectronic devices application, was increased with increasing RF power. The highest $P_{k}$ value of plasma polymerized toluene film (85.27% at 70 W) was higher than that of the plasma polymerized thiophene film (65.17% at 100 W), indicating inhibition of oxygen reduction. The densely packed and tightly interconnected toluene film could act as an efficient barrier layer to the diffusion of molecular oxygen. The result of contact angle measurement showed that the plasma polymerized toluene films have more hydrophobic surface than those of the plasma polymerized thiophene films.

• 센서학회지
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• 제28권1호
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• pp.23-29
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• 2019

A copper tetracumylphenoxy phthalocyanine (CuPccp) thin film was formed on an organic insulator film by Langmuir-Blodgett (LB) deposition for gas sensor fabrication. To increase the reproducibility of film transfer, stearyl alcohol was used as a transfer promoter. The structural properties of the CuPccp layers were optically monitored through attenuated total reflection and polarization-modulated ellipsometry techniques. The average thickness of a single layer of the CuPccp LB film was measured to be 2.5 nm. Despite the role of the transfer promoter, the stability of the layer transfer was not sufficient to ensure homogeneity of the LB film. This was probably due to the presence of aggregates in the molecular structure of the CuPccp LB film. Nevertheless, copper phthalocyanine polymorphism can be greatly suppressed by the LB arrangement, which appears to contribute to the improvement of electrical conductivity. The p-type semiconductor characteristics were confirmed by Hall measurements from the CuPccp LB films.

• 한국표면공학회지
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• 제43권4호
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• pp.176-179
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• 2010

The InAs thin films were grown on GaAs(100) substrate with $2^{\circ}C$ tilted toward [$0\bar{1}\bar{1}$] with different As beam equivalent pressure (BEP) by using molecular beam epitaxy. Growth temperature and thickness of the InAs thin films were $480^{\circ}C$ and 0.5 ${\mu}m$, respectively. We studied the relation between the As BEP and the properties of InAs thin films. The properties of InAs thin films were observed by reflection high-energy electron diffraction (RHEED), optical microscope, and Hall effect. The growth, monitored by RHEED, was produced through an initial 2D (2-dimensional) nucleation mode which was followed by a period of 3D (3-dimensional) island growth mode. Then, the 2D growth recovered after a few minutes and the streak RHEED pattern remained clear till the end of growth. The crystal quality of InAs thin films is dependent strongly on the As BEP. When the As BEP is $3.6{\times}10^{-6}$ Torr, the InAs thin film has a high electron mobility of 10,952 $cm^2/Vs$ at room temperature.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.240-240
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• 2006

Thin films of poly(vinyl cinnamate) (PVCi) were prepared on indium tin oxide (ITO) glass and silicon substrates by conventional spin coating and subsequent drying process. The thicknesses of the films ranged 50-120 nm. The films' surface was treated by rubbing, ultraviolet exposure or their combinations in various ways with changing rubbing strength and exposure dose. These films were examined in detail in the aspects of surface morphology and chain orientation. Further, the anchoring and orientation behaviors of liquid crystals on the film surfaces were investigated. All the results will be discussed in detail.

• Applied Microscopy
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• 제21권2호
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• pp.67-75
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• 1991

[ $C_{60}$ ] molecule, the Buckminsterfullerene, has generated great interest because of its unique molecular structure and of superconductivity exhibited in its alkali-doped solids. We have investigated the molecular stacking and crystal structure of $C_{60}$ thin crystals formed on amorphous carbon film. The $C_{60}$ powder which was chromatographically purified was dissolved in benzene. The thin crystals of $C_{60}$ were observed with a 300 keV transmission electron microscope. Electron diffraction analysis and direct imaging of its molecular stacking were carried out. It was found from this work that the molecules of $10.0{\AA}$ diameter are arrayed hexagonally on substrate surface and $8.7{\AA}$ lattice planes are quite often found in several types of ED patterns, which can never be explained with a fcc model. Therefore the structure of $C_{60}$ thin crystals is hcp, although we cannot fully exclude the possibility of co-existence of hcp and fcc.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.586-589
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• 1999

Organic semiconductors based on conjugated thiophene oligomer have great potential to be utilized as an active layer far electronic and optoelectronic devices. In this study, $\alpha$ -sexithiophene($\alpha$-6T) thin films and various electrode materials were deposited by Organic Molecular Beam Deposition(OMBD) and vacuum evaporation respectively. Those films were photolithographically patterned fur measurements. Electrical characterization of the thin film transistor with various channel length were measured, and field effect mobility is calculated by formula.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1379-1381
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• 1994

In order to investigate the effects of crystal structure in electrical breakdown of polyethylene film. Low molecular materials in polyethylene are removed by the method as follow. Polyethylene was dissolved in xylene and filtered through a glass fiber filter. And then, a polyethylene thin films of thickness $0.5 - 0.9{\mu}m$ are prepared with heat treatment from solution casting. To evaluate the performance of PE film, Electrical breakdown of PE film are measured on M( Al) - I (PE)-M(Al) system.

• Macromolecular Research
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• 제17권7호
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• pp.522-527
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• 2009

A photocrosslinkable polyphosphazene was used for molecular imprinting. We synthesized polyphosphazene (3) having urea groups for complexation with N-carbobenzyloxyglycin (Z-Gly-OH, template) and chalcone groups for cross-linking reaction. As substituents, 4-hydroxycha1cone (1) and N-(4-hydroxyphenyl)-N'-ethylurea (2) were prepared. Choloro groups of poly(dichlorophosphazene) were replaced by the sequential treatment with sodium salts of compounds 1 and 2, and trifluoroethanol. The template molecule was complexed with the urea groups on the polymer chains via hydrogen bonding. A thin polymer film was prepared by casting a solution of the complex of polymer 3 and the template in dimethylformamide on a quartz cell and irradiated with 365 nm UV light to yield a cross-linked film with a thickness of about $16{\mu}m$. The template molecules in the film were removed by Soxhlet extraction with methanol/acetic acid. The control polymer film was prepared in the same manner for the preparation of the imprinted polymer film, except that the template and triethylamine were omitted. In the rebinding test, the imprinted film exhibited much higher recognition ability for the template than the control polymer. We also investigated the specific recognition ability of the imprinted polymer for the template and its structural analogues. The rebinding tests were conducted using Z-Glu-OH, Z-Asp($O^tBu$)-OH, and Z-Glu-OMe. The imprinted film showed higher specific recognition ability for the template and the lowest response for Z-Asp($O^tBu$)-OH.