• 한국표면공학회지
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• 제36권5호
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• pp.406-412
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• 2003

FT-IR and thermography were used to investigate the infrared radiation characteristic of SiO$_2$ film and SiO$_2$/Fe$_2$O$_3$film coated on aluminum. Through FT-TR spectrum, SiO$_2$film showed high infrared absorption in accordance with the stretching vibration of Si-O-Si, and as$ Fe_2$$O_3$was mixed additional absorption band appeared resulting from the stretching vibration of Fe-O at $590cm^{-1}$ and the bond of Si-O-Fe at $900 cm^{-1}$ The two kinds of film measured by the integration method and the reflective method coincided with each other in the wavelength area of infrared absorption and radiation, and corresponded well with Kirchhoff's law as the infrared emissivity is high in wavelength where infrared absorption rate is high. The emissivity of $SiO_2$ film was 0.65 and that of $SiO_2$/Fe$_2$$O_3$film was 0.77, so the addition of$ Fe_2$$O_3$ raised the infrared emissivity by approximately 13%.$ SiO_2$$Fe_2$$O_3$ film is efficient as an infrared radiator at below $100^{\circ}C$. The temperature of heat radiation after 7 minutes was 117$^{\circ}C$ in aluminum plate and $155^{\circ}C$ in $SiO_2$$Fe_2$$O_3$ film, $38^{\circ}C$ higher than the former.

• 한국세라믹학회지
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• 제30권6호
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• pp.433-440
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• 1993

The bioactivity of glasses in the CaO-SiO2 system and CaO-P2O5-SiO2 system with less than 10mol% of P2O5 was investigated by in vitro test in simulated body flood(SBF). The formation of Ca.P film and hydroxyapatite on the surface of glasses after in vitro test was analysed by X-ray photoelectron spectoscopy (XPS), fourier transform infrared reflection spectroscopy (FT-IRRS), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) observation. In the early stage of Ca.P film formation after in vitro test for CaO-SiO2 and CaO-P2O5-SiO2 glasses, the rate of Ca.P film formation on the surface of the glasses was dependent of structural parameter (Y) evaluated from the glass composition. First, in the case of the glasses having Y value below 2, Ca.P film and SiO2-rich layer were formed simultaneously, and there were no differences of the rate of Ca.P film formation in terms of the Y values. Second, in the case of the glasses having Y value above 2, the SiO2-rich layer was formed, and then Ca.P.Si mixed layer was formed in the silica gel structure of the SiO2-rich layer, and finally the Ca.P film on the surface of SiO2-rich layer. The rate of Ca.P film formation delayed as the Y values increased. The rate of hydroxyapatite formation of glasses (the rate of transformation from Ca.P film to hydroxyapatite) seems to be propotional to the rate of Ca.P film formation and Y value. The rate of hydroxyapatite formation of glasses belonging to the second group was delayed as structural parameter increased, and the hydroxyapatite crystal showed spherical growth in the early reaction stage, and then showed silkworm-like linear growth as the reaction time increased.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.3991-3995
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• 2011

$TiO_2-SiO_2-In_2O_3$ nanocomposite thin film was deposited on the glass substrates using a dip coating technique. The morphology, surface composition, surface hydroxyl groups, photocatalytic activity and hydrophilic properties of the thin film were investigated by AFM, XPS, methyl orange decoloring rate and water contact angle measurements. The hydroxyl content for $TiO_2$, $TiO_2-SiO_2$ and $TiO_2-SiO_2-In_2O_3$ nanocomposite films was calculated to be 11.6, 17.1 and 20.7%, respectively. $TiO_2-SiO_2-In_2O_3$ film turned superhydrophilic after 180-min irradiation with respect to pure $TiO_2$ and $TiO_2-SiO_2$ thin films. The photocatalytic decomposition of methyl orange for $TiO_2$, $TiO_2-SiO_2$ and $TiO_2-SiO_2-In_2O_3$ thin films was measured as 38.19, 58.71 and 68.02%, respectively. The results indicated that $SiO_2$ and $In_2O_3$ had a significant effect on the hydrophilic, photocatalytic and self-cleaning properties of $TiO_2$ thin film.

• 한국표면공학회지
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• 제50권5호
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• pp.345-351
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• 2017

A double-layered anti-reflective coating with hydrophilic/abrasion-resistant properties was studied using anatase titanium dioxide($TiO_2$) and silicon oxycarbide($SiO_xC_y$) thin film. $TiO_2$ and $SiO_xC_y$ thin films were sequentially deposited on a glass substrate by DC sputtering and PECVD, respectively. The optical properties were measured by UV-Vis-NIR spectrophotometer. The abrasion-resistance and the hydrophilicity were observed by a taber abrasion tester and a contact angle analyzer, respectively. The $TiO_2/SiO_xC_y$ double-layer thin film had an average transmittance of 91.3%, which was improved by 10% in the visible light region (400 to 800 nm) than that of the $TiO_2$ single-layer thin film. The contact angle of $TiO_2/SiO_xC_y$ film was $6.9^{\circ}$ right after UV exposure. After 9 days from the exposure, the contact angle was $10.2^{\circ}$, which was $33^{\circ}$ lower than that of the $TiO_2$ single-layer film. By the abrasion test, $SiO_xC_y$ film showed a superior abrasion-resistance to the $TiO_2$ film. Consequently, the $TiO_2/SiO_xC_y$ double-layer film has achieved superior anti-reflection, hydrophilicity, and abrasion resistance over the $TiO_2$ or $SiO_xC_y$ single-layer film.

• 공업화학
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• 제25권1호
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• pp.41-46
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• 2014

폴리카보네이트의 표면에 무기계 $SiO_2$ 박막을 바인더로 코팅한 후 광촉매 특성을 갖는 $TiO_2$ 박막을 추가로 형성하여 모재의 특성을 향상시키는 연구가 수행되었다. 바인더로 사용되는 $SiO_2$ 박막은 광투과 특성이 우수하며, 상압플라즈마처리를 통한 친수성의 증가로 $TiO_2$ 함유 수용액의 도포성을 향상시켜 균일한 박막을 형성시킬 수 있었다. 약 200 nm이상으로 코팅된 $TiO_2$ 박막은 180~400 nm의 자외선을 차단하여 폴리카보네이트의 황변현상을 억제하고 내열성을 크게 향상하는데 기여하였다. 최외층에 형성된 $TiO_2$ 박막은 자외선의 흡수로 활성화되는 표면산화특성으로 유기 오염물의 분해반응 촉진과 표면의 친수성의 증가에 따른 자기세정특성을 나타내었다. $TiO_2$ 박막과 폴리카보네이트 기재 사이에 $SiO_2$ 박막의 적용은 기재의 부식에 의한 코팅된 $TiO_2$ 층의 박리를 억제하여 구조 안정성을 유지할 수 있었다.

• 한국산학기술학회논문지
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• 제19권8호
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• pp.14-18
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• 2018

일반적으로 반도체소자의 이동도를 높이기 위하여 반도체소자에서 옴접촉이 중요하게 다루어진다. 반도체 구조의 PN접합은 공핍층을 포함하고 있으며, 공핍층은 전기적인 비선형을 유도하고 쇼키접압을 만들어내는 반도체 고유의 물리적인 특징이다. 본 연구에서는 절연막이 전도성에 미치는 효과를 조사하기 위해서 $SiO_2$ 박막과 $V_2O_5/SiO_2$ 박막의 전기적인 특성을 비교하여 조사하였다. 미소전계영역에서 $SiO_2$ 절연막의 전기적인 특성으로부터 비선형 쇼키접합을 이루고 있는 것을 확인하였으며, 그 위에 증착된 $V_2O_5$ 박막은 오믹특성을 갖는 것을 확인하였다. 절연막의 PN 접합에 의한 쇼키접합 특성이 누설전류를 차단하여 $V_2O_5$ 박막의 전도성을 우수하게 만들었다. 양의 전압에서 $SiO_2$ 박막의 커패시턴스 값은 매우 낮았으나 $V_2O_5$ 박막의 커패시턴스 값은 전압이 증가할수록 증가하였다. 일반적인 전계영역에서 $SiO_2$ 박막의 절연 효과에 의해 $V_2O_5$ 박막의 전도성이 증가하는 것을 확인하였다. 절연박막은 공핍층의 효과를 이용하는 쇼키접합을 갖게 되며, 반도체에서의 쇼키접합은 전도성을 높이는 효과가 있는 것을 확인하였다.

• 한국세라믹학회지
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• 제51권3호
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• pp.197-200
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• 2014

We investigated the influence of blistering on $Al_2O_3$/SiON stacks and $Al_2O_3$/SiNx:H stacks passivation layers. $Al_2O_3$ film provides outstanding Si surface passivation quality. $Al_2O_3$ film as the rear passivation layer of a p-type Si solar cell is usually stacked with a capping layer, such as $SiO_2$, SiNx, and SiON films. These capping layers protect the thin $Al_2O_3$ layer from an Al electrode during the annealing process. We compared $Al_2O_3$/SiON stacks and $Al_2O_3$/SiNx:H stacks through surface morphology and minority carrier lifetime after annealing processes at $450^{\circ}C$ and $850^{\circ}C$. As a result, the $Al_2O_3$/SiON stacks were observed to produce less blister phenomenon than $Al_2O_3$/SiNx:H stacks. This can be explained by the differences in the H species content. In the process of depositing SiNx film, the rich H species in $NH_3$ source are diffused to the $Al_2O_3$ film. On the other hand, less hydrogen diffusion occurs in SiON film as it contains less H species than SiNx film. This blister phenomenon leads to an increase insurface defect density. Consequently, the $Al_2O_3$/SiON stacks had a higher minority carrier lifetime than the $Al_2O_3$/SiNx:H stacks.

• 한국전기전자재료학회논문지
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• 제30권7호
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• pp.447-453
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• 2017

In this study, $Li_2MnSiO_4$ cathode material and LiPON solid electrolyte were manufactured into thin films, and the possibility of their use in thin-film batteries was researched. When the RTP treatment was performed after $Li_2MnSiO_4$ cathode thin-film deposition on the SUS substrate by a sputtering method, a ${\beta}-Li_2MnSiO_4$ cathode thin film was successfully manufactured. The LiPON solid electrolyte was prepared by a reactive sputtering method using a $Li_3PO_4$ target and $N_2$ gas, and a homogeneous and flat thin film was deposited on a $Li_2MnSiO_4$ cathode thin film. In order to evaluate the electrochemical properties of the $Li_2MnSiO_4$ cathode thin films, coin cells using only a liquid electrolyte were prepared and the charge/discharge test was conducted. As a result, the amorphous thin film of RTP treated at $600^{\circ}C$ showed the highest initial discharge capacity of about $60{\mu}Ah/cm^2$. In cases of coin cells using liquid/solid double electrolyte, the discharge capacities of the $Li_2MnSiO_4$ cathode thin films were comparable to those without solid LiPON electrolyte. It was revealed that $Li_2MnSiO_4$ cathode thin films with LiPON solid electrolyte were applicable in thin film batteries.

• 한국재료학회지
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• 제13권10호
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• pp.697-702
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• 2003

FT-IR and thermograph were used to investigate the infrared radiation characteristics of $SiO_2$film made by the sol-gel method. FT-IR spectrum of the $SiO_2$film showed high infrared absorption by Si-O-Si vibration at 1220, 1080, 800 and cm$460^{-1}$ The infrared absorption and radiation wavelength ranges of the $SiO_2$film measured by the integration method coincided with the reflection method, and the infrared emissivity was 0.65, equally. Depending on the bonding of elements, the infrared emissivity was high in the wavelength range where the infrared absorption rate was high, that follows the Kirchhoff's law. The emissivity showed the highest value in the wavelength range between $8∼10\mu\textrm{m}$. $SiO_2$film was considered as an efficient materials for infrared radiator at temperature below 10$0^{\circ}C$. The heat radiation temperature was $117^{\circ}C$ for the aluminum plate, but $146^{\circ}C$ for the $SiO_2$film after 7 minutes heat absorption, consiquently, $29^{\circ}C$ higher than the former.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.140-143
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• 2002

In this study, we prepared ZnO/glass and $ZnO/SiO_{2}/Si$ thin film by Facing Targets Sputtering (FTS) system for Film Bulk Acoustic Resonator (FBAR). When the ZnO thin film applied to piezoelectric thin film, it requires good c-axis preferred orientation. And c-axis orientation has a remarkable difference with preparation conditions. Therefore, c-axis orientation must be significantly evaluated according to changing deposition conditions. Moreover, in order to prepare ZnO thin film with good crystallographic properties and progressive of efficiency of product process, the ZnO thin film should have to prepared as low temperature as possible. In this work, we prepared ZnO thin films on slide glass and $SiO_{2}/Si$ substrate. And the crystallographic characteristics of ZnO thin films on sputtering conditions were investigated by alpha-step and X-ray diffraction.