Ar/$O_2$에 따른 ZnO 박막의 C-축 배향성에 관한 연구

이동윤,박용욱,남산,이전국,김현재,윤석진,황금찬,Lee, Dong-Yoon,Park, Yong-Wook,Nam, Sahn,Lee, Jeon-Kook,Kim, Hyun-Jai,Yoon, Seok-Jin,Whang, Keum-Chan 한국전기전자재료학회 2000 전기전자재료학회논문지 Vol.13 No.7

Zinc Oxide(ZnO) thin films on Si(100) substrate were deposited by RF magnetron reactive sputtering. The charcteristics of ZnO thin films on argon/oxygen(Ar/O$_2$)gas ratios RF power and substrate temperature were investigated by XRD, SEM, and AFM analyses. C-axis preferred orientation resistivity and surface roughness highly depended on Ar/O$_2$gas ratios. The resistivity of ZnO thin films rapidly increased with increasing oxygen ratio and the resistivity value of 9$\times$10$^{7}$ $\Omega$cm was obtained at a working pressure of 10 mTorr with Ar/O$_2$=50/50. The surface roughness was also improved with increasing oxygen ratio and the ZnO films deposited with Ar/O$_2$=50/50 showed the excellent roughness value of 28.7$\AA$.

염료감응형 태양전지와 열전발전소자를 결합한 복합 태양전지의 구조 및 특성

이동윤,송재성,이원재,김인성,정순종,Lee, Dong-Yoon,Song, Jae-Sung,Lee, Won-Jae,Kim, In-Sung,Jeong, Soon-Jong 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.4

The tandem solar cell composed of a dye-sensitized solar cell (DSC) and a thermoelectric generator (TEG) was designed. In such new cell, the characteristics of DSC and TEG were investigated. DSC uses the wavelength range of 380∼750 nm and has the maximum efficiency of below 10 %. If the solar light transmitted through DSC can be converted to heat energy, TEG can generate electric energy using this heat energy. By this means, it is possible to utilize most of solar energy in the wavelength range of 350∼3000 nm for electric generation and it can be expected to obtain higher solar energy conversion efficiency exceeding the known limit of maximum efficiency. For this purpose we suggest the tandem solar cell constructed with DSC and TEG. In this structure, DSC has a carbon nanotube film as a counter electrode of DSC in order to collect the solar light and convert it to heat energy. We measured the I-V characteristics of DSC and TEG, assembled to the tandem cell. As a result, it was shown that DSC with carbon nanotube and TEG had the efficiency of 9.1 % and 6.2 %, respectively. From this results, it is expected that the tandem solar cell of the new design has the possibility of enhanced conversion efficiency to exceed above 15 %.

범밀도함수법을 이용하여 계산한 IIIB족 원소가 도핑된 ZnO의 전자상태

이동윤,이원재,민복기,김인성,송재성,김양수,Lee, Dong-Yoon,Lee, Won-Jae,Min, Bok-Ki,Kim, In-Sung,Song, Jae-Sung,Kim, Yang-Soo 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.7

The electronic states of ZnO doped with Al, Ga and In, which belong to III family elements in periodic table, were calculated using the density functional theory. In this study, the calculation was performed by two Programs; the discrete variational Xa (DV-Xa) method, which is a sort of molecular orbital full potential method; Vienna Ab-initio Simulation Package (VASP), which is a sort of pseudo potential method. The fundamental mixed orbital structure in each energy level near the Fermi level was investigated with simple model using DV-Xa. The optimized crystal structures calculated by VASP were compared to the measured structures. The density of state and the energy levels of dopant elements were shown and discussed in association with properties.

SAW 필터용 ZnO 압전 박막의 전기적 특성

이동윤,윤석진,Lee, Dong-Yoon,Yoon, Seok-Jin 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.10

The structural and electrical property of RF magnetron sputtered ZnO thin film have been studied as a function of RF power, substrate temperature, oxygen/argon gas ratio and film thickness at constant sputtering power, sputtering working pressure and target-substrate distance. To analyze a crystallo-graphic properties of the films, $\theta$/2$\theta$ mode X-ray diffraction, SEM, and AFM analyses. C-axis preferred orientation, resistivity and surface roughness highly depended on oxygen/argon gas ratio. The resistivity of ZnO thin film(6000 ${\AA}$) rapidly increased with increasing oxygen ratio and the resistivity value of $9 {\ast} 10^7 {\Omega}cm$ was obtained at a working pressure of 10 mTorr with the same oxygen/argon gas ratio. The surface roughness was also improved with increasing oxygen ratio and the ZnO films deposited with the same oxygen/argon gas ratio showed the excellent roughness value of 28.7 ${\AA}$. With increase of the substrate temperature, The C-axis preferred orientation of ZnO thin film increases and the resistivity decreases due to deviation from the stoichiometric ZnO due to oxygen deficiency.

La₂O₃가 첨가된 Pd/TiO₂ 촉매의 개발 및 H₂ 상온산화 반응에서의 성능 향상 연구

이동윤 ( Dong Yoon Lee ),김성철 ( Sung Chul Kim ),이상문 ( Sang Moon Lee ),김성수 ( Sung Su Kim ) 한국공업화학회 2020 공업화학 Vol.31 No.6

본 연구에서는 상온 조건에서 추가적인 에너지원 없이 H₂ 산화가 가능한 Pd/TiO₂ 촉매를 제조하였고, 지지체인 TiO₂의 비표면적은 Pd/TiO₂ 촉매의 H₂ 산화 반응 성능과 비례하지는 않은 것을 확인하였다. 또한 촉매의 물성 변화에 의한 성능 영향 평가를 위하여 La₂O₃를 Pd/TiO₂ 촉매에 첨가하였다. La₂O₃를 TiO₂에 함량별로 첨가하여 Pd/La₂O₃-TiO₂를 제조하였고, CO chemisorption 분석을 진행하였다. Pd/TiO₂ (G) 촉매의 전환율(14% at 0.5% H₂)과 비교하여 Pd/La₂O₃-TiO₂ 촉매가 74% 전환율로 5배 이상의 성능 증진이 나타났다. Pd/La₂O₃-TiO₂ 촉매는 활성금속인 Pd의 metal dispersion이 클수록 H₂ 산화반응에 유리한 것으로 분석되었다. 하지만 첨가되는 La2O3가 10%를 초과하게 되면 촉매 성능이 다시 감소하는 것을 알 수 있었다. 마지막으로 Pd/La₂O₃-TiO₂ 촉매의 물성이 지배적인 영향을 미치는 것은 주입되는 H₂가 0.3~0.5% 농도 조건까지이며, 1% 이상의 H₂ 농도부터는 물질전달이 촉매 반응속도를 지배하는 것으로 판단된다. In this study, a Pd/TiO₂ catalyst which oxidized H₂ at room temperature without an additional energy source was prepared. And a specific surface area of TiO₂ as a support was not proportional to H₂ oxidation reaction performance of Pd/TiO₂ catalyst. In addition La₂O₃ was added to Pd/TiO₂ catalyst in order to evaluate the performance effect due to the change of catalysts physical properties. A Pd/La₂O₃-TiO₂ was prepared by adding different amounts of La₂O₃ to TiO₂ and CO chemisorption analysis was performed. Compared to the conversion rate (14% at 0.5% H₂) of the Pd/TiO₂ (G) catalyst, the Pd/La₂O₃-TiO₂ catalyst showed 74% which was improved by more than five times. It was found that the larger the metal dispersion of Pd as an active metal is, the more favorable to H₂ oxidation reaction is. However, when the added La₂O₃ amount exceeded 10%, the catalyst performance decreased again. Finally, it was concluded that the physical properties of the Pd/La₂O₃-TiO₂ catalyst have a dominant influence on the catalytic activity until 0.3~0.5% of injected H₂ concentrations and the catalyst reaction rate was controlled by substance transfer from 1% or more concentrations of H₂.

선거제도와 정당정치, 그리고 민주주의 : 한국과 태국의 비교 연구

이동윤 ( Lee Dong-yoon ) 한국태국학회 2008 한국태국학회논총 Vol.15 No.1

The purpose of this study is to explore the electoral systems and party politics of South Korea and Thailand, and to investigate the similarities and deferences in the process of democratic transition and consolidation after democratization. As a result of this research, South Korea and Thailand democratized in 1987 and 1992 respectively went through a similar process at the dimension of competitiveness of electoral system. Constitution, electoral law and political party laws were democratized to complete institutional and procedural democracy. In reality, however, the electoral behaviors and party politics of two countries did not completely shed off the old legacy of authoritarianism such as money politics, dissolution and merger of political parties, political leader-led decision making, and lack of inter-party democratization. At the dimension of stability of electoral process and party politics, these two countries had various immature problems of democratic attitude and political orientation. In sum, the stabilizing and consolidating a new democracy after democratization is needed to guarantee the stability of electoral process and party politics as well as the competitiveness of electoral system.

공구 중심점의 변위 최소화를 위한 문형 공작기계의 크로스레일 개선 연구

이동윤(Dong-Yoon Lee),이명규(Myung-Gyu Lee),이종훈(Jong-Hoon Lee),최학봉(Hag-Bong Choi) 한국생산제조학회 2011 한국생산제조시스템학회 학술발표대회 논문집 Vol.2011 No.4

General portal machine represents a distinct weak spot concerning their structural behavior because of long protruding structure components, such as saddle & ram. TCP was chosen as a reference point for evaluating the contortion effect of Crossrail. The structural analysis of two cases were performed and the displacement of the TCP were compared. The purpose of this study is to minimize contortion through design improvement of crossrail.

태국의 정당정치와 민주주의

이동윤(Dong-Yoon Lee) 한국정치학회 2003 한국정치학회보 Vol.37 No.3

대의민주주의를 기반으로 하는 현대 국가에 있어서 정당정치는 민주정치의 본질을 형성하는 중요한 기틀이며, 올바른 민주정치의 실현은 정당정치의 발전과 분리되어 생각될 수 없다. 이에 따라 본 연구는 태국의 정당정치 변동과정을 민주주의의 기본 속성인 ‘경쟁성’(competitiveness)과 ‘안정성’(stability) 개념을 중심으로 분석함으로써 태국의 각 시기별 정당정치 변동과정과 민주주의의 발전경로를 그 변화와 지속성 차원에서 살펴보았다. 여기서 정당정치의 민주적 속성을 규정하는 정당정치의 ‘경쟁성’은 정당의 설립 및 정치활동, 선거참여, 선거경쟁 등과 관련된 제도적 환경과 그 제도의 실질적 운영에 있어서 표출되는 자유로운 정치참여 및 선거경쟁의 보장을 의미하며, 정당정치의 ‘안정성’ 이란 정당체계의 유효정당수와 선거진 동성. 개별 정당들의 이념과 대중적 침투 수준, 정당의 규모 및 조직구조 등을 통하여 평가되는 정당정치의 지속적이고 안정적인 성향을 뜻한다. 또한 이 두 가지 요인은 정당정치의 제도화 수준과 연관되어 정치체제의 유형과 민주주의 수준을 규정한다. 분석결과 태국의 정당정치 변화에 따른 민주주의 발전경로는 초기 정치과정에서 빈번하게 발생한 군사 쿠데타로 인하여 정당정치의 경쟁성이 높고 낮은 수준을 반복하는 가운데 그 안정성이 낮게 나타남으로써 정치체제의 유형이 불안정한 민주주의체제와 불안정한 비민주주의체제 사이를 왕복하는 혼란스러운 악순환을 경험하다가 1973년 제1차 민주화 이후 정당정치의 경쟁성은 높으나 안정성이 낮은 불안정한 민주주의 체제를 형성하였으며, 1980년대 쁘렘 정권의 탄생으로 정당정치의 경쟁성은 중간 수준이나 그 안정성이 낮은 준민주주의체제를 유지하여 왔다는 사실을 알 수 있었다. 또한 1992년 제2차 민주화 이후 태국의 정당정치는 다시 정당정치의 경쟁성 수준은 높고 그 안정성은 낮은 불안정한 민주주의체제로 회귀하였으나, 1973년의 제1차 민주화 시기보다 높은 정당정치의 안정성을 나타냄으로써 민주주의 공고화에 보다 근접한 정당정치 양상을 보여 주었다. Thailand has been on the track of building a new democracy since 1992, and party politics has emerged as a critical factor determining success/failure of democratic consolidation. This study analyzes changes and continuities between Thai party politics and the development of democracy. For theoretical and systematic analysis of their relationships, this study uses two variables of 'competitiveness' and 'stability' of party politics. The competitiveness of party politics means that institutions should be arranged for free establishments, political activities and election campaigns, which guarantee real and practical competition among political parties. Stability means durability and steadiness of party politics, which can be measured by effective number of political parties, electoral volatility, ideological distance of political parties, party structure, and the size of political parties. After analyzing party politics in Thailand, we find that competitiveness and stability of party politics is closely related to the level of democracy. From 1946 to 1973, Thai party politics had repeated between low level and high level of competitiveness, stability but too much unstable, so Thai democracy also had repeated between unstable democratic system and unstable non-democratic system. From 1973 to 1976, Thai party politics had achieved high level of competitiveness, but stability had been continually low. In the period of semi-democracy (1976-1991), especially under the rule of Prime Minister Prem, competitiveness of party politics has been medium level, but stability was low level. After the second democratization in 1992, party politics has recovered its competitiveness. But stability of party politics is still low. which interrupts democratic consolidation in Thailand. Nevertheless the level of stability in this period somewhat rises than in the period of the first democratization, it is making the future of Thai democracy more brighter. When Thai party politics ensures its high competitiveness and stability, a successful consolidation of democracy can also be expected.

동남아의 북한 인권정책: 탈북자 문제를 중심으로

이동윤(Lee, Dong-Yoon) 연세대학교 동서문제연구원 2009 동서연구 Vol.21 No.2

이 연구는 최근 동남아 지역에서 발생하고 있는 탈북자 문제를 중심으로 동남아 국가들의 북한 인권정책을 포괄적으로 살펴보고, 제반 문제점과 한국 정부에의 정책적 시사점을 점검하는데 주요 목적이 있다. 최근 들어 탈북자 들에 대한 중국 정부의 단속과 체포, 그리고 북한으로의 강제 송환이 강화되 자, 탈북자들은 보다 안전한 제3국으로의 탈출을 위해 동남아 국가들로 밀입 국하는 사례가 증가되고 있다. 그러나 이러한 상황 속에서도 동남아 국가들의 탈북자 문제나 북한 인권정책은 아직도 소극적인 태도를 벗어나지 못하고 있다. 그것은 이들 국가들과 남북한 사이의 미묘한 외교관계 때문이기도 하지만, 지역협의체인 아세안(ASEAN)을 중심으로 펼쳐지고 있는 이들 국가 들의 외교정책 노선이 인권 문제에 관해 상대적으로 취약하기 때문이기도 하다. 결과적으로 동남아 국가들에서 발생하고 있는 탈북자 문제를 보다 원활하게 해결하기 위해서는 한국 정부의 정책적 노력과 조용한 외교가 계속 되어야 하며, 특히 국제사회의 관심과 더불어 비정부 인권단체들을 활용한 보다 적극적인 구호와 지원정책이 활성화되어야 할 것이다. The purpose of this study is to examine the Southeast Asia s human rights policies toward North Korea with focus on North Korean Refugees, and to consider the problems and policy implications for resolving the problems of North Korean refugees in Southeast Asia. Actually, the North Korean refugees illegal entry into Southeast countries was increasing more and more when the Chinese government strengthened crackdown and compulsory repatriation of North Korean refugees. In Southeast Asian countries, however, their human rights policies toward North Korea does not get out of lukewarm attitude. The reason of their attitude is not only caused to the delicate diplomatic relationship between Southeast Asian countries and North and South Korea, but also caused by the relative fragility of the ASEAN s policy line on human rights problems. Conclusionally, for the harmonious solution of North Korean refugees problems which was occurring in Southeast Asia, it needs the calm diplomacy and continuous efforts of South Korean government, especially active rescue and aid policy, which is using non-governmental human rights groups along with concerns of international society.

지방선거와 정당공천제 논쟁

이동윤(Lee Dong-Yoon) 서강대학교 현대정치연구소 2010 현대정치연구 Vol.3 No.1