• Title/Summary/Keyword: Sol formation

검색결과 312건 처리시간 0.03초

Synthesis of Silicon Carbide Nanowhiskers from Coconut Fibres and Sol-Gel Derived Silica

  • Raman, V.;Bhatia, G.;Mishra, A.;Saha, M.;Sengupta, P.R.;Srivastava, A.K.
    • Carbon letters
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    • 제7권3호
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    • pp.166-170
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    • 2006
  • Silicon carbide whiskers ($SiC_w$) having the diameter in the range of 20-80 nm were synthesised from coconut fibres through sol-gel process. The coconut fibres were impregnated with tetraethoxysilane and methyltriethoxysilane derived sol and pyrolyzed at $1400^{\circ}C$ in argon. X-ray of the pyrolyzed samples showed the formation of ${\beta}$-SiC.

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광학용 무용제 실리카-아크릴 모노머 하이브리드 졸 기반의 코팅액 제조 및 특성 평가 (Fabrication and Characteristics of Non-Solvent Silica-Acryl Monomer Hybrid Sol for Optical Device)

  • 강우규;장건익
    • 한국전기전자재료학회논문지
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    • 제32권3호
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    • pp.246-251
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    • 2019
  • A solvent free, highly concentrated silica-acryl monomer hybrid sol was synthesized using aqueous colloidal silica as a precursor. The effects of the silica particle size, type of surface treatment agent employed, and silica content on the formation of the hybrid sol were systematically studied. The optical and physical properties of the coating solution prepared using the hybrid sol were also characterized. The viscosity of the hybrid sol tended to decrease as the particle size of the silica and the molecular weight of the surface treatment agent increased. The PET substrate coated with MPTMS-Mix (mixture, 70 wt%) solution showed the highest surface hardness (6 H) and low surface roughness ($Ra=0.044{\mu}m$), which could be attributed to an increase in packing density caused by the infiltration of small particles into the pores formed between larger particles.

Sol-Gel 법을 이용한 PLT(28) 박막의 제작과 특성 (Preparation and Characteristics of PLT(28) Thin Film Using Sol-Gel Method)

  • 강성준;정양희;류재흥
    • 한국정보통신학회논문지
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    • 제9권7호
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    • pp.1491-1496
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    • 2005
  • [ $Pb_{0.72}La_{0.28}TiO_3$ ] (PLT(28)) 박막을 sol-gel 법을 이용하여 제작한 후, 그 특성을 조사하여 ULSI DRAM 의 캐패시터 절연막으로서의 적용 가능성을 연구하였다. Sol-gel 법의 출발 물질로는 acetate 계를 사용하였다. TGA-DTA 분석을 통하여 PLT(28) 박막의 sol-gel 법에 의한 공정 조건을 확립하였다. 매 coating 후 $350^{\circ}C$ 에서 drying 하고, 마지막으로 $650^{\circ}C$ 에서 annealing 하여 $100\%$ perovskite 구조를 가지는 치밀하고 crack 이 없는 PLT(28) 박막을 얻었다. $Pt/Ti/SiO_2/Si$ 기판 위에 PLT(28) 박막을 형성하여 전기적 특성을 측정하였다. 그 결과 유전 상수와 누설전류밀도가 각각 936 과 $1.1{\mu}A/cm^2$ 으로 측정되었다.

Sol-Gel 법을 이용한 PLT(28) 박막의 제작과 특성 (Preparation and Characteristics of PLT(28) Thin Film Using Sol-Gel Method)

  • 강성준;정양희;류재홍
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 추계종합학술대회
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    • pp.865-868
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    • 2005
  • $Pb_{0.72}La_{0.28}TiO_3$ (PLT(28)) 박막을 sol-gel 법을 이용하여 제작한 후, 그 특성을 조사하여 ULSI DRAM 의 캐패시터 절연막으로서의 적용 가능성을 연구하였다. Sol-gel 법의 출발 물질로는 acetate계를 사용하였다. TGA-DTA 분석을 통하여 PLT(28) 박막의 sol-gel 법에 의한 공정 조건을 확립하였다. 매 coating 후 350$^{\circ}C$에서 drying 하고, 마지막으로 650$^{\circ}C$에서 annealing 하여 100% perovskite 구조를 가지는 치밀하고 crack 이 없는 PLT(28) 박막을 얻었다. Pt/Ti/SiO$_2$/Si 기판 위에 PLT(28) 박막을 형성하여 전기적 특성을 측정하였다. 그 결과 유전 상수와 누설전류밀도가 각각 936 과 1.1${\mu}$A/cm$^2$ 으로 측정되었다.

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졸-겔법에 따른 실리카 유리 제조에 있어서 DCCA의 역할에 관한 연구 (The Role of DCCA in the Sol-Gel Process Preparing Silica Glass)

  • 박용완;연석주
    • 한국세라믹학회지
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    • 제28권6호
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    • pp.488-494
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    • 1991
  • In this study, the effects of catalyst and DCCA content were investigated in order to determine the optimum conditions of monolithic silica gel formation through sol-gel process. Formamide, oxalic acid, glycerol and dimethylformamide are used as DCCA. To observe the phenomena in drying and heat-treating of gels, we examined structural exchange of gels using FT-IR, TG-DTA and XRD. Monolithic gels were obtained by adding formamide and dimethylformamide as DCCA. According to the heat treatment schedule, silica glass is prepared by heat-treatment up to 1050$^{\circ}C$.

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Preparation of Hybrid Proton Conductor by Sol-Gel Process from Nafion Solution

  • Kim, Sang-Ock;Kim, Jeong-Soo
    • Macromolecular Research
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    • 제10권3호
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    • pp.174-177
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    • 2002
  • Proton-conducting hybrid materials composed of silica and Nafion polymer were prepared from the sol-gel synthesis of silica in aqueous Nafion solution. The compositions of hybrid proton conductors were adjusted with the changing ratios of tetraethyl orthosilicate to Nafion. The thermal analysis, FTIR, SEM, and X-ray diffraction studies have proved the formation of Nafion/silica hybrid materials and no remarkable phase separation was observed, which led to an assumption that the macromolecular chain of silica and Nafion was homogeneously interlaned.

Thin Oxide Functional Films by Metal Alkoxide Method

  • Natalya, Korobova
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.9-16
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    • 2000
  • A survey over the role of sol-gel processing and metal alkoxides in the thin film preparation is given. The basic chemistry of the sol-gel process is complex due to the different reactivities of the network forming and the wide variety of reaction parameters. Despite the important progress in the investigations of the mechanisms of thin film formation, a direct relation of reaction parameters to functional oxide properties is still very difficult.

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Sol-Gel Processing for Preparation of Metal Oxide Films

  • Korobova Natalya;Soh, Dea-Wha
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.259-264
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    • 2000
  • Systematic research of metal alkoxide electrophoretic deposition has been developed. The formation mechanism of electrophoretic deposits has been offered. The structure study of dry and heat-treated electrophoretic deposits has been established. The concrete examples of one and bi-component oxide thin film formation were considered. The new approaches for thin film technology have developed on various substrates of different shapes and sizes. The correlation between thin film structure, mechanism of their formation, and physico-chemical properties has been determined.

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졸-겔법에 의한 강유전성 PZT 박막의 제조;(I) 킬레이팅 에이전트를 이용한 안정화 PZT 졸의 합성 및 박막의 제조 (Preparation of Ferroelectric PZT Thin Film by Sol-Gel Processing; (I) Synthesis of Stable PZT Sol Using Chelating Agent and Preparation of Its Thin Film)

  • 김병호;홍권;조홍연
    • 한국세라믹학회지
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    • 제31권7호
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    • pp.804-812
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    • 1994
  • Stable PZT coating sol was prepared using chelating agent, ethylacetoacetate(EAcAc) by sol-gel processing under ambient atmosphere. Through FT-IR spectrum analysis on solution of each reaction step, formation of metal complex was confirmed and prepared PZT sol was stable over several months. Through TG-DTA, XRD, FT-IR spetrum analysis of PZT gel powder, it was understood that the addition of EAcAc could reduce the transition temperature to ferroelectric phase, due to the increased homogeneity by matching the hydrolysis and condensation rates by chelation. Single perovskite phase was obtained by the heat-treatment at 54$0^{\circ}C$ for 30 min. The film was coated on ITO-coated glass substrate by dip coating method. After heat-treatment, PZT thin film had thickness in the range of 20~130 nm. The maximum dielectric constant of its thin film at room temperature and 1 kHz was 128.

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Sol-Gel 공정을 이용한 ZnO 쇼트키 다이오드의 제작 및 특성평가 (Fabrication and Characterization of ZnO Schottky Diode Using Sol-Gel Process)

  • 이득희;김경원;박기호;김상식;이상렬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.390-390
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    • 2010
  • We fabricate Schottky diodes with the contact between a sol-gel derived ZnO layer and Au that guarantees the expected Schottky contact due to the high work function. The formed single metal Schottky barrier shows characteristics comparable to the barrier formed by alloys. Au is deposited by thermal evaporation on a ZnO thin film that is optimally formed under sol-gel process conditions of a 1-mol zinc acetate concentration and a 3000-rpm coating speed. Possible defects. which can provide deleterious current paths. are minimized by patterning the deposited Au. The I-V curve verifies the formation of a Schottky contact. Measurements showed that the Schottky barrier height and leakage current at -5 V were 0.6 eV and $1{\times}10^{-12}A$. respectively.

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