• KIEE International Transactions on Electrophysics and Applications
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• v.11C no.2
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• pp.32-36
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• 2001

We investigate the surface order, defects and morphology of hexagonal columnar mesophases, Having a crown ether at one end which forms the center of the column and three fluorinated tails at the other, The orientation of the columns was successfully controlled by surface anchoring: Columns were aligned perpendicularly to an evaporated carbon surface, and the planar alignment do asymmetric compounds was induced by a water surface. TEM images show that there is a high degree of perfection in the packing do the cylinders. The hexagonal columnar mesophase (F(sub)h) was confirmed by direct images and the corresponding electron diffractions, where ordered cylindrical moieties are packed on a hexagonal lattice. The column of 12F8-ABG-15C5 was much straighter, compared with that of 12F8-AG-B15C5, resulting from the degrees of regular stacking. Elementary edge dislocation, grain boundary and +1/2 disclination have been observed, although the defects are generally rare.

• Transactions on Electrical and Electronic Materials
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• v.7 no.4
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• pp.204-209
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• 2006

Photo Resist (PR) ashing process was carried out with the atmospheric pressure- dielectric barrier discharge (ADBD) using $SF_6/N_2/O_2$. Ashing rate (AR) was sensitive to the mixing ratio of the oxygen and nitrogen of the blower type of ADBD asher. The maximum AR of 5000 A/min was achieved at 2% of oxygen in the $N_2$ plasma. With increasing the oxygen concentration to more than 2% in the $N_2$ plasma, the discharge becomes weak due to the high electron affinity of oxygen, resulting in the decrease of AR. When adding 0.5% of SF6 to $O_2/N_2$ mixed plasma, the PR AR increased drastically to 9000 A/min and the ashed surface of PR was smoother compared to the processed surface without $SF_6$. Carbon Fluorinated polymer may passivate the PR surface. It was also observed that the glass surface was not damaged by the fluorine.

• Journal of the Korean Chemical Society
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• v.23 no.3
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• pp.132-135
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• 1979

The thermal decomposition of a dilute mixture of 1,1,2,2,-$C_2H_2F_4$ in argon has been investigated in a single-pulse shock tube between 1146 and $1232^{\circ}K$ at total reflected shock pressures of about 3000 torr. Under these conditions the reaction proceeds exclusively by the molecular elimination of hydrogen fluoride. It has been found that the asymmetric isomer with the fully fluorinated ${\alpha}$-carbon requires the higher activation energy which may be attributed to the difference in atomic charge densities between isomers. The rate constant ratio is given by $log(k_1/k_2) = -0.069 {\pm} 0.021 ＋(1388{\pm}113) / 2.303RT$ in good agreement with previous independent studies.

• Journal of the Korean Vacuum Society
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• v.7 no.4
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• pp.368-373
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• 1998

As device dimensions approach submicrometer size in ULSI, the demand for interlayer dielectric materials with very low dielectric constant is increased to solve problems of RC delay caused by increase in parasitic resistance and capacitance in multilevel interconnectins. Fluorinated amorphous carbon in one of the promising materials in ULSI for the interlayer dielectric films with low dielectric constant. However, poor thermal stability and adhesion with Si substrates have inhibited its use. Recently, amorphous hydrogenated carbon (a-C:H) film as a buffer layer between the Si substrate and a-C:F has been introduced because it improves the adhesion with Si substrate. In this study, therfore, a-C:F/a-C:H films were deposited on p-type Si(100) by ECRCVD from $C_2F_6, CH_4$and $H_2$gas source and investigated the effect of forward power and composition on the thickness, chemical bonding state, dielectric constant, surface morphology and roughness of a-C:F films as an interlayer dielectric for ULSI. SEM, FT-IR, XPS, C-V meter and AFM were used for determination of each properties. The dielectric constant in the a-C:F/a-C:H films were found to decrease with increasing fluorine content. However, the dielectric constant increased after furnace annealing in $N_2$atomosphere at $400^{\circ}C$ for 1hour due to decreasing of flurorine content. However, the dielectric constant increased after furnace annealing in $N_2$atmosphere at $400^{\circ}C$ for 1hour due to decreasing of fluorine concentration.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.653-658
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• 2021

Polyvinylidene fluoride (PVDF) is a promising coating material because of its outstanding processability. The PVDF coating, however, has limitations in anti-corrosion application due to its weak hydrophobicity compared to that of other fluoropolymers. In this study, plasma fluorination was performed using carbon tetrafluoride (CF₄) gas to improve anti-corrosion properties of PVDF. The fluorine content and hydrophobicity of PVDF were investigated in different CF₄ flow rates, followed by the determination of anti-corrosion properties. The fluorine content on the surface of the PVDF film increased by up to 46.70%, but the surface free energy was independent of CF₄ flow rate. Meanwhile, the surface roughness of the PDVF film tended to increase by up to 150% and then decrease with increasing CF₄ flow rate. It is considered that the plasma fluorination affects the surface free energy due to the introduction of fluorine functional groups and surface etching. In addition, the degree of corrosion of the PVDF-coated Fe plate was significantly reduced from 49.2% to 19.0% compared to that of the uncoated Fe plate. In particular, the degree of corrosion of the fluorinated PVDF-coated Fe plate was 13.6%, which was 28.4% lower than that of the PVDF-coated Fe plate, showing improved anti-corrosion protection.

• Journal of Climate Change Research
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• v.3 no.2
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• pp.117-128
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• 2012

The Government of South Korea has continued its effort to fixate virtuous circle of economic growth and climate change response to cope with international demands and pressure to commitment for greenhouse gas reduction effectively. Nationally, Korean Government has established "Enforcement of the Framework Act on Low carbon, Green Growth"(2010. 4. 13) to implement national mid-term GHG mitigation goal(30% reduction by 2020 compare to BAU), which established the foundation for phased GHG mitigation by setting up the sectoral and industrial goal, adopting GHG and Energy Target Management System. Also, follow-up measures are taken such as planning and control of mid-term and short-term mitigation target by detailed analysis of potential mitigation of sector and industry, building up the infrastructure for periodic and systematic analysis of target management. Likewise, it is required to establish more accurate, reliable and detailed sectoral GHG inventory for successfully establishment and implement the frame act. In comparison to the $CO_2$ emission, Especially fluorinated greenhouse gases (HFCs, PFCs, $SF_6$) are lacking research to build the greenhouse gas inventories to identify emissions sources and collection of the applicable collection activities data. In this study, with the refrigeration and air conditioning sector being used to fluorine refrigerant(HFCs) as the center, greenhouse gas emission estimation methodology for evaluating the feasibility of using this methodology look over and mobile air conditioning, fixed air conditioning, household refrigeration equipment, commercial refrigeration equipment for the greenhouse gas emissions were calculated. First look at in terms of methodology, refrigeration and air conditioning sector GHG emissions in developing country-specific emission factors and activity data of the industrial sector the construction of the DB is not enough, it's 2006 IPCC Guidelines Tier 2a (emission factor approach) rather than the Tier 2b (mass balance approach) deems appropriate, and each detail by process, sectoral activity data more accurate, if DB is built Tier 2a (emission factor approach) can be applied will also be judged. Refrigeration and air conditioning sector in 2009 due to the use of refrigerant greenhouse gas emissions ($CO_2eq.$) assessment results, portable air conditioner 1,974,646 ton to year, fixed-mount air conditioner 1,011,754 ton to year, household refrigeration unit 4,396 ton to year, commercial refrigeration equipment 1,263 ton to year was estimated to total 2,992,037 tons.