• Title/Summary/Keyword: C-O bond

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Study on the nucleophilic reaction on Orgniac Thin Films (유기물 박막에서 일어나는 친핵성 반응에 대한 연구)

  • Oh, Teresa;Kim, Hong-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.170-171
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    • 2006
  • The chemical shift of SiOC film was observed according to the flow rate ratio. SiOC film has the broad main band of $880{\sim}1190cm^{-1}$ and the sharp Si-$CH_3$ bond at $1252cm^{-1}$, and the infrared spectra in the Si-O-C bond moved to low frequency according to the increasing of an oxygen flow rate. The chemical shift affected the carbon content in the SiOC film, and the decreasing of carbon atoms elongated the C-H bonding length, relatively. The main bond without the sharp Si-$CH_3$ bond at $1252cm^{-1}$ consisted of Si-C, C-O and Si-O bonds, and became the bonding structure of the Si-O-C bond.

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Relationship between Dielectric Constant and Increament of Si-O bond in SiOC Film (SiOC 박막에서 Si-O 결합의 증가와 유전상수의 관계)

  • Oh, Teresa
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.11
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    • pp.4468-4472
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    • 2010
  • SiOC films made by the inductively coupled plasma chemical vapor deposition were researched the relationship between the dielectric constant and the chemical shift. SiOC film obtained by plasma method had the main Si-O-C bond with the molecule vibration mode in the range of $930{\sim}1230\;cm^{-1}$ which consists of C-O and Si-O bonds related to the cross link formation according to the dissociation and recombination. The C-O bond originated from the elongation effect by the neighboring highly electron negative oxygen atoms at terminal C-H bond in Si-$CH_3$ of $1270cm^{-1}$. However, the Si-O bond was formed from the second ionic sites recombined after the dissociation of Si-$CH_3$ of $1270cm^{-1}$. The increase of the Si-O bond induced the redshift as the shift of peak in FTIR spectra because of the increase of right shoulder in main bond. These results mean that SiOC films become more stable and stronger than SiOC film with dominant C-O bond. So it was researched that the roughness was also decreased due to the high degree of amorphous structure at SiOC film with the redshift after annealing.

Factors Influencing S-O Bond and C-O Bond Cleavages in the Reactions of 2,4-Dinitrophenyl X-Substituted Benzenesulfonates with Various Nucleophilic Reagents

  • 엄익환;김정주;김명진;권동숙
    • Bulletin of the Korean Chemical Society
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    • v.17 no.4
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    • pp.353-357
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    • 1996
  • Second-order rate constants have been measured spectrophotometrically for the reaction of 2,4-dinitrophenyl X-substituted benzenesulfonates with Z-substituted phenoxides in absolute ethanol at 25.0±0.1 ℃. The nucleophilic substitution reaction gives both S-O bond and C-O bond cleavage products. The extent of S-O bond cleavage increases significantly with increasing electron withdrawing ability of the sulfonyl substitutent X, while that of the C-O bond cleavage is independent on the electronic effect of the substituent. On the contratry, the effect of the substituent Z in the nucleophilic phenoxide is more significant for the C-O bond cleavage than for the S-O bond cleavage. Aminolyses of 2,4-dinitrophenyl benzenesulfonate (1) with various 1°, 2° and 3°amines have revealed that steric effect is little important. The extent of S-O bond cleavage increases with increasing the basicity of the amines, but decreases with increasing the basicity of the nucleophilic aryloxides, indicating that the HSAB principle is not always operative. Besides, reactant and solvent polarizability effect has also been found to be an important factor in some cases but not always to influence the reaction site.

MO Studies of Configuration and Conformation (Ⅰ). Configuration and Conformation of Methyl Benzamidoxime (配置와 形態에 關한 分子軌道論的 硏究 (第1報). Methyl Benzamidoxime의 配置와 形態)

  • Shi Choon Kim;Ikchoon Lee
    • Journal of the Korean Chemical Society
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    • v.20 no.2
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    • pp.111-117
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    • 1976
  • The configuration and conformation of methyl benzamidoxime have been studied from extended Huckel molecular orbital calculations.The results show that the E-configuration of the C=N double bond is favored compared with that of Z-configuration with the sp-conformation of the C-N bond rotamers, but Z-configuration is more stable with the ap-conformation of the C-N bond rotamers. The conformation of C-N bond with equal configuration of C=N bond and equal conformation of N-O bond, sp-form is favored, but the conformation of N-O bond with equal configuration and equal conformation of C-N bond ap-form is more stable. The major part of the stabilization energies can be accounted for by the electrostatic energies between the atoms involved.

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Chemical Properteis and Contact Angle on SiOC (SiOC 박막의 접촉각과 화학적 특성의 상관성)

  • Oh, Teresa;Kim, Hong-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.205-205
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    • 2007
  • The SiOC film of carbon centered system was prepared using bistrimethylsilylmethane and oxygen mixed precursor by the chemical vapor deposition. The chemical properties of the SiOC film were analyzed by the I-V measurement and FTIR spectra. The main bond of 950~1200 cm-1 was composed of the Si-C, Si-O-C and Si-O bonds. The leakage current of the SiOC film increased with the increasing of the carbon content, and the drift of the current was similar to the Si-O-C bond content.

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Physical Properties of Thin Films Generated by Two Kinds of Different Function (2가지 서로 다른 기능에 의해 생성된 박막의 물리적인 특성의 기원)

  • Oh, Teresa
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.487-488
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    • 2008
  • SiOC films containing alkyl groups have a low dielectric constant because of the interaction between the C-H hydrogen bonds and the oxygen of high electro-negative atom. The Si-$CH_3$ in a void is broken by the $O_2$, therefore the strength of CH bond in Si-O-O-$CH_3$ bond increases. The Si-O-O-$CH_3$ bond is broken by nucleophilic attack due to Si atom, again. The elongation of C-H bond causes the red shift, and the compression of C-H bond causes the blue shift. Among these chemical shifts, the blue shift from $1000\;cm^{-1}$ to $1250\;cm^{-1}$ was related with the formation of pores. If the oxygen is deficient condition, the methylradicals of the electron-rich substitution group terminate easily the Si-O-Si cross-link, and the pore is originated from the cross-link breakdown due to much methyl radicals of Si-$CH_3$. The dielectric constant of the films decreases due to pore generation.

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Generation of Si-O-C Bond without Si-$CH_3$ Bond in Hybrid Type SiOC Film

  • Oh, Teresa
    • Journal of the Semiconductor & Display Technology
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    • v.7 no.3
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    • pp.1-4
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    • 2008
  • The chemical shift of SiOC film was observed according to the flow rate ratio. SiOC film had the broad main band of $880\sim1190cm^{-1}$ and the sharp Si-$CH_3$ bond at $1252cm^{-1}$, and the peak position of the main bond in the infrared spectra moved to high frequency according to the increasing of an BTMSM flow rate. So the increment of the alkyl group induced the C-H bond condensation in the film, and shows the blueshift in the infrared spectra. In the case of P5000 system of Applied Materials Corporation, the strong bond of Si-CH3 bond in precursor does not enough to dissociated and ionized, because low plasma energy due to the capactive coupled CVD. Therefore, there was the sharp peak of Si-$CH_3$ bond at $1252cm^{-1}$.

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Theoretical Studies on the Gas-Phase Alkylation of Delocalized Ambident Anions with Methyl Fluoride

  • 이익춘;박형연;한인숙;김창곤;김찬경;이본수
    • Bulletin of the Korean Chemical Society
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    • v.20 no.5
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    • pp.559-566
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    • 1999
  • Gas-phase alkylations of delocalized ambident anions, Y---CH---X- where X, Y=CH2, O, or S, have been investigated theoretically at the MP2/6-31+G*//MP2/6-31+G* and QCISD/6-31+G*//MP2/6-31+G* lev-els. O-and S-alkylations (X=O and S) are more favored kinetically by ΔE^≠ = 4.6 and 9.8 kcal mol-1 than the respective C-alkylations even though they are thermodynamically less favored by 22.4 and 6.0 kcal mol-1 respectively. It was found that the transition structures for the C-alkylations are imbalanced due to the endoergic rehybridi-zation of the carbon center from sp2 to sp3 which leads to premature bond contraction of the C-Y bond and delayed bond stretching of the C-X bond. In the O-, or S-alkylation, such endoergic process is not required since the σ-lone pair on O or S is involved in the initial stage of alkylation. The imbalanced TSs for the C-alkylation are accompanied by higher intrinsic barriers and deformation energies.

Characteristic Properties of Organic Thin Film Surface on Si Semiconductor (XRD 분석과 FTIR 분석에 의한 비정질 박막의 특성 연구)

  • Oh, Teresa
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.112-113
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    • 2007
  • $SiO_2$ 절연 박막위에 희석된 PMMA 유기물을 처리하였다. 유기물 처리량에 따른 $SiO_2$ 박막의 $620{\sim}1100\;cm^{-1}$ 영역의 FTIR 스펙트라를 분석한 결과 0.3~0.7%로 PMMA 처리된 박막에서 친핵성 반응이 밀어나는 것을 확인하였으며, 친핵성 반응이 일어나는 박막들에서 누설전류가 적었으며, 절연특성이 우수한 것을 확인하였다.

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The Molecular Structure and Conformational Stability of Cyclobutylmethyl Ketone by MM2

  • Lee, Mu-Sang;Jung, Young-Mee
    • Bulletin of the Korean Chemical Society
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    • v.10 no.3
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    • pp.247-250
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    • 1989
  • The molecular structure of cyclobutylmethyl ketone (c-$C_4H_7COCH_3$) has been investigated by molecular mechanics II (MM2). For the monosubstituted cyclobutane there are two possible ring conformations, the equatorial and axial form, but for the cyclobutylmethyl ketone the equatorial form is predominant conformation. For the $COCH_3$ moiety there are two stable orientations which are the equatorial-gauche and the equatorial-trans form. The equatorial-gauche form where the C = O bond is nearly eclipsing (torsional angle ${\angle}C4-C3-C2-O10=14.5^{\circ}$) one of the ${\alpha}$C-C bonds of the four-membered ring was preferred conformer with steric energy of 13.37 kcal/mol. The equatorial-trans form where the C = O bond is nearly eclipsing (${\angle}C4-C3-C2-O10=145.0^{\circ}$) the ${\alpha}$ C-H bond of the four-membered ring was less stable conformer with steric energy of 15.40 kcal/mol.