논문 : 습식제련 ; 수용액에서 염화은의 구리흡착거동에 관한 연구

안태항 ( Tae Hang Ahn ),김진현 ( Jin Hyeon Kim ),이원해 ( Won Hae Lee ) 대한금속재료학회 ( 구 대한금속학회 ) 1996 대한금속·재료학회지 Vol.34 No.11

For the purpose of establishing basic data to purify silver, the adsorption behavior of Cu(II) ion on AgCl in aqueous solution was studied in the presence of chloride ion. The results obtained were as follows : 1. The adsorption of Cu(II) ion on AgCl increases with increasing the concentration of NaCl, and it is reasonable to assume that CuCl- is supposed to be adsorbed. And Langmuir adsorption isotherm, when applied to the isotherm data, was obeyed. 2. The adsorption of Cu(II) ion on AgCl with HCI is about half as much as that with NaCl. 3. In the presence of Ag- ion of higher concentration, the adsorption of Cu(II) ion on AgCl is similar to that which has been shown to be adsorbed with HCl. 4. The adsorption of Cu(II) ion on AgCl decreases with increasing the temperature, and the enthalpy of adsorption is -8.0kJ/mol.

리모트 수소 플라즈마를 이용한 Si 표면의 금속오명 제거

박명구,안태항,이종무,전형탁,류근걸,Park, Myeong-Gu,An, Tae-Hang,Lee, Jong-Mu,Jeon, Hyeong-Tak,Ryu, Geun-Geol 한국재료학회 1996 한국재료학회지 Vol.6 No.7

리모트 수소 플라즈마를 이용하여 실리콘 웨이퍼 표면 위에 있는 금속불순물의 제거 및 제거기구에 관하여 조사하였다. 실리콘의 표면과 내부분석을 위하여 TXRF(total reflection x-ray fluorescence)와 SPV(surface photovoltage), AFM(atomic force microscope)을 사용하였다. TXRF 분석결과 리모트 수소 플라즈마가 금속오염물질 제거에 상당한 효과가 있는 것으로 나타났다. TXRF분석결과 리모트 수소 플라즈마가 금속오염물질 제거에 상당한 효과가 있는 것으로 나타났다. 리모트 수소플라트마 처리 후 금속오염은 금속원소의 종류에 따라 1010atoms/$\textrm{cm}^2$-1011atoms/$\textrm{cm}^2$수준이었다. SPV분석결과를 보면 수소 플라즈마 처리에 의해 minority carrier 수명이 전반적으로 증가하였다. AFM 분석을 통하여 수소 플라즈마 처리가 표면 손상을 일으키지 않으며 표면의 거칠기에 나쁜 영향을 미치지 않음을 알 수 있었다. 또한 본 실험에서 나타난 결과들을 종합해 볼 때 금속오염물의 제거기구는 자연산화막 혹은 수소로 passivate된 실리콘 웨이퍼 표면을 수소 플라즈마에서 발생된 수소원자가 실리콘표면을 약하게 에칭할 때 떨어져 나가는 'lift-off'가 유력한 것으로 판단된다.

The Study on the Cu Impurity Removal Depending on the Cleaning Splits of ( UV/O3 + HF ) and ( H2O2 + HF )

최백일,이원준,안태항,전형탁 대한전자공학회 1997 대한전자공학회 학술대회 Vol.1997 No.1

HVCVD를 이용한 다결정 SiGe 박막의 증착 및 활성화 메카니즘 분석

강성관,고대흥,전인규,양두영,안태항 한국진공학회 1999 한국진공학회 학술발표회초록집 Vol.- No.-

Poly Si₁-xGex의 산화 거동 분석

강성관,고대홍,이기철,양두영,안태항,주문식 한국진공학회 2000 한국진공학회 학술발표회초록집 Vol.- No.-

리모트 수소 플라즈마를 이용한 Si 표면 위의 Fe 불순물 제거

이종무,박웅,전부용,전형탁,안태항,백종태,신광수,이도형,Lee, C.,Park, W.,Jeon, B.Y.,Jeon, H.T.,Ahn, T.H.,Back, J.T.,Shin, K.S.,Lee, D.H. 한국재료학회 1998 한국재료학회지 Vol.8 No.8

리모트 수소 플라즈마에 의한 Si 웨이퍼 표면 위의 Fe 불순물의 제거효과를 조사하였다. 세정시간 10분 이하와 rf-power 100W이하의 범위에서 최적 공정조건은 각각 1분과 100W이였으며, 플라즈마 노출시간이 짧을수록, rf-power가 증가할수록 Fe제거 효과가 더 향상되는 것으로 나타났다. 또한, 고압보다는 저압 하에서 Fe 제거효과가 더 우수하였는데, 저압 하에서는 $\textrm{H}_2$ 유량이 20sccm, 고압 하에서는 60sccm일 때 Fe 제거효과가 가장 우수하였다. 플라즈마 세정 직후의 열처리는 금속오염의 제거효과를 향상시켰으며, $600^{\circ}C$에서 최상의 효과를 얻을 수 있었다. AFM 분석결과에 의하면 표면 거칠기는 플라즈마 세정에 의하여 30-50% 향상되었는데, 이것은 Fe 오염물과 더불어 Si 표면의 particle이 제거된 데 기인하는 것으로 생각된다. 또한 본 논문에서는 수소 플라즈마에 의한 Si 웨이퍼 표면의 Fe 제거기구에 관해서도 자세히 고찰하였다. Effects of remote hydrogen plasma cleaning process parameters on the removal of Fe impurities on Si surfaces and the Fe removal mechanism were investigated. Fe removal efficiency is enhanced with decreasing the plasma exposure time and increasing the rf-power. The optimum plasma exposure time and rf-power are 1 min and 100W. respectively, in the range below 10 min and 100W. Fe removal efficiency is better under lower pressures than higher pressures, and the optimum $\textrm{H}_2$ flow rate was found to be 20 and 60sccm, respectively, under a low and a high pressure. The post-RHP(remote hydrogen plasma) annealing enhanced metallic contaminants removal efficiency, and the highest efficiency was achieved at $600^{\circ}C$. According to the AFM analysis results Si surface roughness was improved by 30-50%, which seems to be due to the removal of particles by the plasma cleaning. Also. Fe impurities removal mechanisms by remote hydrogen plasma are discussed.

리모트 수소 플라즈마를 이용한 Si 기판 위의 Cu 불순물 제거

이종무,전형탁,박명구,안태항,Lee, Jong-Mu,Jeon, Hyeong-Tak,Park, Myeong-Gu,An, Tae-Hang 한국재료학회 1996 한국재료학회지 Vol.6 No.8

리모트 수소 플라즈마를 이용하여 Si 기판 위의 구리 오염의 제거 효과에 관하여 조사하였다. 최적의 공정 조건을 찾기 위하여 Si 기판을 1ppm ${CuCI}_{2}$ 표준 화학 용액으로 인위적으로 오염시킨 후 rf power와 세정시간, 거리 (수소플라즈마 중심에서 Si 기판표면까지의 거리)등의 공정 변수를 변화시키며 리모트 수소 플라즈마 세정을 실시하였다. 리모트 수소 플라즈마 세정 후 Si 표면의 분석을 위하여 TXRF(total x-ray reflection fluorescence)와 AFM(atomic force microscope)측정을 실시하였다. 리모트 수소 플라즈마 세정이 Cu의 제거에 효과적이며 Si 표면의 거칠기에 나쁜 영향을 주지 않음을 TXRF와 AFM 분석결과로부터 알 수 있었다. Cu 불순물의 흡착 메커니즘은 산화 환원 전위 이론으로 설명될 수 있으며, Cu 불순물의 제거 메커니즘은 XPS(x-ray photoelectron spectroscopy)분석결과를 근거로 하여 다음과 같이 설명할 수 있다. :먼저 Cu 이온이 Si 표면에 흡착되어 화학적 산화막을 생성한다. 그 다음, 수소 플라즈마 중의 반응성이 강한 수소이온이 이 산화막을 분해시켜 제거하며 Cu 불순물은 산화막이 제거될 때 함께 제거된다. Removal of Cu impurities on Si substrates using remote H-plasma was investigated. Si substrates were intentionally contaminated by 1ppm ${CuCI}_{2}$, standard chemical solution. To determine the optimal process condition, remote H-plasma cleaning was conducted varying the parameters of rf power, cleaning time and remoteness(the distance between the center of plasma and the surface of Si substrate). After remote H-plasma cleaning was conducted, Si surfaces were analysed by TXRF(total x-ray reflection fluorescence) and AFM(atomic force microscope). The concentration of Cu impurity was reduced by more than a factor of 10 and its RMS roughness was improved by more than 30% after remote H-plasma cleaning. TXRF analysis results show that remote H-plasma cleaning is effective in eliminating Cu impurity on Si surface when it is performed under the optimal process condition. AFM analysis results also verifies that remote H-plasma cleaning makes no damage to the Si surface. The deposition mechanism of Cu impurity may be explained by the redox potential(oxidation-reduction reaction potential) theory. Based on the XPS analysis results we could draw a conclusion that Cu impurities on the Si substrate are removed together with the oxide by a "lift-off" mechanism when the chemical oxide( which forms when Cu ions are adsorbed on the Si surface) is etched off by reactive hydrogen atoms.gen atoms.

후속 열처리에 따른 W / WNx / poly Si₁-xGex의 계면 반응 및 W / WNx / poly Si₁-xGex MOS Capacitor 구조의 전기적 특성 분석

강성관,김재진,고대홍,강한별,양철웅,안태항,여인석,이태완,이영호 한국진공학회 2001 한국진공학회 학술발표회초록집 Vol.- No.-

A Study on Oxidation Behavior of Poly-Si1-xGex Films

강한별,양철웅,민병기,고대홍,J. H. Lee,강성관,안태항,여인석,K. C. Lee,T. W. Lee,Y. H. Lee 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.42 No.III

We have investigated the oxidation behavior of poly-Si$_{1-x}$Ge$_x$ films with 20 \%, 40 \%, and 60 \% Ge content in both dry and wet oxygen ambient. Poly-Si$_{1-x}$Ge$_x$ films with various compositions and about 1000 {\AA} in thickness were deposited on oxidized Si wafers (with 1000 {\AA} thick thermal SiO$_2$). Oxidation was carried out in a conventional tube furnace at 800 $^\circ$C. The composition and thickness of the oxide were analyzed by RBS using rump simulation. The redistribution and chemical bonding of Si, Ge, and O elements were analyzed by XPS. The microstructure and phases formed in the films were analyzed by HR-TEM. In this study, it was found that Si was oxidized preferentially when the content of Ge in the alloy was low (20 \%, 40 \%). SiO$_2$ was formed on the poly-Si$_{1-x}$Ge$_x$ films, rejecting Ge and the oxidation rate of the poly-Si$_{1-x}$Ge$_x$ films depends weakly on the Ge concentration. On the other hand, Si and Ge were oxidized simultaneously when the content of Ge was high (60 \%). The formation of a mixed oxide layer on the poly-Si$_{1-x}$Ge$_x$ films was observed. It was also found that oxide surface has a tendency to be flat from the initial oxidation stage due to the fast oxidation rate of Ge-rich films.

자기효능감과 기업성과

이종건(Jong Keon Lee),김현철(Hyeon Cheol Kim),안태항(Tae Hang Ahn) 한국경영학회 2014 經營學硏究 Vol.43 No.2

Entrepreneurial orientation and entrepreneurial experience are useful as explanatory variables in explaining the effects of self-efficacy on firm performance. According to the upper echelon theory, CEO plays a critical role in shaping and positioning the organization strategically to achieve performance, using their personal traits of individuals to influence organizational dynamics(Carmeli, 2008). Although previous research has suggested that self-efficacy had a positive effect on firm performance(Drnovsek & Glas, 2002; Hmielesky & Baron, 2008; Westerberg, Singh, & Hackner, 1997), there is limitation in explaining how self-efficacy influences firm performance. Attention has been turned to entrepreneurial orientation (EO) in explaining entrepreneurial performance (Moruku, 2013). Entrepreneurial experience has been suggestedas an useful explanatory variable to account for firm performance (Lee & Tsang, 2001; Schiller& Crewson, 1997). Little attention has been turned to the role of entrepreneurial experience in the entrepreneurial orientation-firm performance relationship. The present study, therefore, developed the new research model that includes entrepreneurial orientation and entrepreneurial experience, extending the current model that includes the effect of self-efficacy on firm performance. This study examined relationships among self-efficacy, entrepreneurial orientation, entrepreneurial experience, and firm performance. Data were collected from 146 entrepreneurs in Korea. We used path analysis and regression analysis to test the direct and indirect effects of self-efficacy on perceptual measures of firm performance, as well as how firm performance might be moderated by entrepreneurial experience. Entrepreneurial orientation was used as the mediating variable for explaining the relationship between self-efficacy and firm performance. Entrepreneurial experience was used as the moderating variable for explaining the relationship between entrepreneurial orientation firm performance. Results indicated that self-efficacy and entrepreneurial orientation were positively related to firm performance. Self-efficacy also influenced firm performance positively through its effect on entrepreneurial orientation. Especially, entrepreneurial experience strengthened the positive relationship between entrepreneurial orientation and firm performance. The authors discuss both the study``s implications and future research directions.