• 마이크로전자및패키징학회지
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• 제12권4호통권37호
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• pp.345-349
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• 2005

300 mW-cm의 낮은 비저항을 갖는 카본-질소$\_$텅스텐 (W-C-N) 확산방지막을 원자층 증착법으로 제조하였으며, 반응기체로 $WF_6-N_2-CH_4$를 사용하였다. $N_2$ 및 $CH_4$ 반응기체를 주입 할 때는 고주파 펄스를 인가하여 플라즈마에 의한 반응물의 분리가 일어나도록 하였다. 다층금속배선에 사용하는 층간 절연층 (TEOS) 위에서 W-C-N 박막은 원자층 증착기구를 따르며, 10에서 100 사이클 동안 증착율이 0.2nm/cycles 로 일정한 값을 가진다. 또한 Cu 배선을 위한 확산방지막으로써 W-C-N 박막은 비정질 상을 가지며, $800^{\circ}C$에서 30분간 열처리해도 Cu의 확산을 충분히 방지할 수 있음을 확인하였다.

• 한국세라믹학회지
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• 제39권10호
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• pp.981-987
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• 2002

$St\"{o}ber$ process를 이용하여 단분산 콜로이드 실리카를 제조하였다. 초기물질인 TEOS(Tetraethylorthosilicate)와 $NH_4OH$, 에탄올 및 증류수의 함유량을 조절하여 100 nm급, 200 nm급, 300 nm급 크기의 단분산 실리카 입자를 제조할 수 있었고, 제조된 실리카 입자는 Scanning Electron Microscope(SEM) 및 laser scattering particle analyzer를 통해 관찰하였다. Dipcoating 공정을 이용하여 제조된 300 nm 크기의 콜로이드 실리카의 자기 배열성(self-assembly) 형성에 관한 연구를 진행하였다. 다양한 코팅 공정 변수(표면장력, 표면전하, 입자의 함유량)의 조절을 통하여 dip coating시에 자기 배열성 단층막(monolayer)을 형성해 낼 수 있는 조건을 최적화하였고, SEM으로 관찰해 본 결과, 최적 조건 상태에서 비교적 넓은 영역 (1.5 mm ${\times}$ 1.5 mm)에서 hexagonally ordered packing된 콜로이드 입자 결정 단층막을 얻을 수 있었다.

• 멤브레인
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• 제24권6호
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• pp.438-447
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• 2014

무정형의 괴상의 다공성 borosilicate는 trimethylborate (TMB)/ tetraethylorthosilicate (TEOS) 몰비 0.01~0.10 겔체를 $700{\sim}800^{\circ}C$ 온도범위에서 열처리 하였을 때 얻어졌다. BET와 SEM 관찰에 의하면 $700{\sim}800^{\circ}C$에서 얻어진 borosilicate의 표면적은 $251.12{\sim}355.62m^2/g$이고, 기공직경은 3.5~4.9 nm이며, 입자크기는 30~60 nm이었다. TGA측정에 의하면 borosilicate가 poly[1-(trimethylsilyl)propyne](PTMSP)에 첨가되었을 때 PTMSP-borosilicate 복합막의 열적 안정성은 향상 되었다. SEM관찰에 의하면 borosilicate는 $1{\mu}m$ 크기로 복합막 내에 분산되어 있었다. 기체투과실험에 의하면 PTMSP에 borosilicate 함량이 증가하면 자유부피, 공동, 기공률이 증가하여 기체투과가 용해확산에 의한 것보다 분자체거름, 표면확산, Knudsen 확산에 의해 일어나는 경우가 점차 증가함으로 해서 $H_2$와 $N_2$의 투과도는 증가하고 선택도($H_2/N_2$)는 감소하였다.

• 한국분말재료학회지
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• 제23권6호
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• pp.442-446
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• 2016

The sol-gel method is the simplest method for synthesizing monodispersed silica particles. The purpose of this study is to synthesize uniform, monodisperse spherical silica nanoparticles using tetraethylorthosilicate (TEOS) as the silica precursor, ethanol, and deionized water in the presence of ammonia as a catalyst. The reaction time and temperature and the concentration of the reactants are controlled to investigate the effect of the reaction parameters on the size of the synthesized particles. The size and morphology of the obtained silica particles are investigated using transmission electron microscopy and particle size analysis. The results show that monodispersed silica particles over a size range of 54-504 nm are successfully synthesized by the sol-gel method without using any additional process. The nanosized silica particles can be synthesized at higher TEOS/$H_2O$ ratios, lower ammonia concentrations, and especially, higher reaction temperatures.

• 대한기계학회논문집B
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• 제25권9호
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• pp.1175-1182
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• 2001

Chemical compositions of polydisperse SiO$_2$/TiO$_2$multicomponent aggregates were measured for different heights from the burner surface and different mobility diameters of aggregates. SiO$_2$/TiO$_2$multicomponent particles were generated in a hydrogen/oxygen coflow diffusion flame from two sets of precursors: TTIP(titanium tetraisopropoxide), TEOS(tetraethylorthosilicate). To maintain 1:1 mole ratio of TTIP:TEOS vapor, flow rate of carrier gas $N_2$was fixed at 0.6lpm for TTIP, at 0.1lpm for TEOS. In-situ sampling probe was used to supply particles into DMA(differential mobility analyzer) which was calibrated with using commercial DMA(TSI, model 3071A) and classifying monodisperse multicomponent particles. Classified monodisperse particles were collected with electrophoretic collector. The distributions of composition from particles to particle were determined using EDS(energy dispersive spectrometry) coupled with TEM(transmission electron microscope). The chemical(atomic) compositions of classified monodisperse particle were obtained for different heights; z=40mm, 60mm, 80mm. The results suggested that the chemical(atomic) composition of SiO$_2$decreased with the height from burner surface and the composition of SiO$_2$and TiO$_2$approached to the value of 1 to 1 fat downstream. It is also found that the composition of SiO$_2$decreases as the mobility diameter of aggregate increases.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.441-446
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• 2000

Chemical compositions of monodisperse $SiO_2/TiO_2$ multicomponent aggregates were measured for different heights from the burner surface and different mobility diameters of aggregates. $SiO_2/TiO_2$ multicomponent particles were generated in a hydrogen/oxygen coflow diffusion flame from two sets of precursors: TTIP (titanium tetraisopropoxide), TEOS(tetraethylorthosilicate). To maintain 1:1 mole ratio of TTIP:TEOS vapor theoretically, flow rate of carrier gas $N_2$ was fixed at 0.61pm for TTIP, at 0.11pm for TEOS. In situ sampling probe was used to supply particles into differential mobility analyzer(DMA) which was calibrated with using commercial DMA(TSI 3071A) and classifying monodisperse multicomponent particles. Classified particles were collected with electrophoretic collector. The distributions of composition from particle to particle were determined using EDS (energy dispersive spectrometry) coupled with TEM (transmission electron microscope). The chemical (atomic) compositions of classified monodisperse particle were obtained for different heights; z=40mm, 60mm, 80mm. The results suggested that the atomic composition of $SiO_2$ decreased with the height from burner surface and the composition of $SiO_2$ and $TiO_2$ approached to the value of 1 to 1 in far downstream. It is also found that the composition of $SiO_2$ decreases as the mobility diameter of aggregate increases.

• Bulletin of the Korean Chemical Society
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• 제27권3호
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• pp.399-402
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• 2006

Porous organic-inorganic hybrids have been prepared from tetraethylorthosilicate (TEOS) and organosilane precursors by sol-gel method. Two organosilanes, 3-(2,4-dinitrophenylamino)propyltriethoxysilane (DNPTES) and N-[[(2-nitrophenyl)methoxy]carbonyl]-3-triethoxysilylpropylamine (NPTES) were used to incorporate electron-accepting (di)nitrophenyl groups into the hybrids. The hybrids were characterized by FT-IR spectroscopy and elemental analysis, and their pore characteristics were studied by nitrogen sorption porosimetry. Surface area of the hybrids ranged from 563 to 770 $m^2$/g, pore volume, 0.23-0.30 $cm^3$/g, and porosity, 35-41%. It was demonstrated by UV-vis spectroscopy that aniline, ethylenediamine, and 1-aminonaphthalene could be removed from their hexane solutions in the presence of the hybrid powders. The removal of amines is attributable to donor-acceptor interaction between the electron-donating amines and electron-accepting (di)nitrophenyl moiety.

• 한국응용과학기술학회지
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• 제33권3호
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• pp.421-427
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• 2016

Nanosized hollow silica was prepared by $St{\ddot{o}}ber$ method in the presence of aluminum isopropoxide. The mixture of polyelectrolytes such as poly(sodium 4-styrene sulfonate)(PSS) and polyacrylic acid(PAA) were used as templates. Tetraethylorthosilicate(TEOS) and aluminum isopropoxide were used as precursors for silica and alumina, respectively. The function of aluminum isopropoxide is to increase the porosity of silica shell. The characterizations of hollow silica were examined by TEM(transmission electron microscopy), TGA(thermogravimetric analysis), BET(Brunauer Emmett Teller), Energy-dispersive X-ray spectroscopy(EDS), and FT-IR spectrum. It was found that the shell thickness of hollow silica was around 8 nm and the core diameter was around 20 nm by TEM.

• 한국막학회:학술대회논문집
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• 한국막학회 1996년도 추계 총회 및 학술발표회
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• pp.55-57
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• 1996

다공성 무기막은 높은투과도와 뛰어난 내열.내화학성, 그리고 경제성 때문에 기존의 PSA공정이나 증류와 같은 고에너지 분리공정을 대체하는 공정으로 각광을 받고 있다. 무기재료막의 제조하는 방법으로 주로 알콕사이드를 사용하는 솔-젤법(1)과 금속(2) 또는 기상반응(3)을 이용하는 화학증착법이 사용된다. 또한 고온에서 수소를 연속적으로 분리하여 화학평형에 기인한 한계를 극복하여 높은 수율을 얻고자하는 막반응기에 관한 연구가 활발히 진행되고 있다. 본 연구에서는 $\alpha$-알루미나 지지체의 미세한 다공성 구조 내부에서 TEOS(Tetraethylorthosilicate)와 산성의 알코올-물 혼합물을 확산시켜 실리카 솔을 생성시킴과 동시에 젤화시켜 기공의 크기를 감소시켜 막을 제조하였다. 이렇게 제조된 막은 높은 투과도와 낮은 수소선택도(selectivity=3-4)를 보였고, 두번째 단계로 silica sol을 제조하여 진공 하에서 dip-coating을 행하였다. 이렇게 2단계로 기공 구조를 개선시킨 실리카 막은 저압에서 상대적으로 높은 수소의 분리도(selectivity=5-7)를 보였으며 여전히 높은 투과도를 갖는다.

• Journal of Ceramic Processing Research
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• 제13권spc2호
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• pp.373-376
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• 2012

Thin films of Ag-SiO2-TiO2 composite oxides with SiO2/TiO2 of 20/80 molar compositions were prepared by the sol-gel method, using tetraethylorthosilicate (TEOS) and titanium isopropoxide (TIP) as precursors. Ag-SiO2-TiO2 films coated on commercial glass substrates have successfully been synthesized using sol-gel method. The Ag-SiO2-TiO2 film with 0.5% Ag-added concentration and 20 mol% SiO2-mixture gives optimal results on crystalline structure, optical property, surface area, and photochromic property. Absorption near the wavelength of the incident light decreased gradually. The reversibility of the two-photon writing process in Ag-SiO2-TiO2 film is clearly seen.