Chemical Bath Depsoition법에 의한 $Cd_{1-x}$$Zn_x$/S 박막의 제조 및 특성에 관한 연구

송우창,이재형,김정호,박용관,양계준,유영식 한국전기전자재료학회 2001 전기전자재료학회논문지 Vol.14 No.2

Structural, optical and electrical properties of Cd$_{1-x}$ Zn$_{x}$S films deposited by chemical bath deposition(CBD), which is a very attractive method for low-cost and large-area solar cells, are presented. Especially, in order to control more effectively the zinc component of the films, zinc acetate, which was used as the zinc source, was added in the reaction solution after preheating the reaction solution and the pH of the reaction solution decreased with increasing the concentration of zinc acetate. The films prepared after preheating and pH control had larger zinc component and higher optical band gap. The crystal structures of Cd$_{1-x}$ Zn$_{x}$S films was a wurtzite type with a preferential orientation of the (002) plane and the lattice constants of the films changed from the value for CdS to those for ZnS with increasing the mole ratio of the zinc acetate. The minimum lattice mismatch between Cd$_{1-x}$ Zn$_{x}$S and CdTe were 2.7% at the mole ratio of (ZnAc$_2$)/(CdAc$_2$+ZnAc$_2$)=0.4. As the more zinc substituted for Cd in the films, the optical transmittance improved, while the absorption edge shifted toward a shorterwavelength. the photoconductivity of the films was higher than the dark conductivity, while the ratio of those increased with increasing the mole ratio of zinc acetate. acetate.

Growth and Characterization of ZnxCd1-xS Films Prepared by Using Chemical Bath Deposition for Photovoltaic Devices

송우창,이재형 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.4

The structural, optical and electrical properties of ZnxCd1-xS films deposited by using chemical bath deposition (CBD), which is a very attractive method for low-cost and large-area solar cells, are presented. Especially, in order to more effectively control the zinc component of the films, we mixed zinc acetate in a reaction solution after preheating. The properties of the CdS thin films were analyzed by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet (UV)-spectrophotometer. The pH of the reaction solution was found to decrease with increasing concentration of zinc acetate. As the proportion of zinc acetate in the mixture was increased, the transmittance was improved and the optical band gap was increased

해방 초기 북한의 화교학교 재건과 중국공산당 및 북한정부의 역할

송우창 인천대학교 중국학술원 2020 비교중국연구 Vol.1 No.1

This paper is on the reconstruction of North Korea's Chinese schools in the early stages of liberation and focuses on the Chinese Communist Party (CCP) and the North Korean government’s roles. Shortly after liberation, Chinese schools in North Korea sat abeyant due to lack of funds. In the early 1940s, with the support of the Wang Jing-wei regime and the local Chinese Chamber of Commerce, additional Chinese schools were established under the leadership of the Chinese Consulate. Conflicts over juridical legitimacies between the Soviet army and the Consulate of the Wang regime led to consuls and several overseas Chinese arrests, resulting in several Chinese merchants fleeing to Seoul and Chinese school closure between August 1945 and early 1946. In August 1946, a CCP office of the Northeast Bureau was established in Pyongyang. This representative agency accepted the request from North Korea to create an organization to manage North Korea's Chinese. The Overseas Chinese Federation (OCF), established in Pyongyang, aimed to promote Chinese participation in support activities for the Chinese army and social construction in North Korea. This research details how the OCF fostered Chinese involvement in North Korea. The efforts included the 1948 Chinese civil war target of ameliorating the shortage of teachers and financial difficulties of Chinese schools with the transfer of Chinese schools to the North Korean government. The research further examines the Chinese and North Korean student friendship activities and the system reforms within the Chinese schools. The findings also provide evidence that education policy of North Korean government encouraged local Chinese students to participate in the social construction of North Korea. 본 연구는 해방 초기 북한 화교학교의 재건사업 과정에서 중국공산당과 북한정부가 어떤 역할을 했는지를 중심으로 검토한 것이다. 해방 직후 북한의 화교학교 운영은 마비 상태에 빠져있었는데, 가장 심각한 문제는 자금난이었다. 1940년대 초반, 조선 주재 왕징웨이 정권의 중국영사관과 각지의 중화상회가 주도하여 화교학교를 증설했다. 그러나 1945년 8월 북한에 진주한 소련군은 왕징웨이정권의 영사관원을 반소분자로 분류하여 이듬해 3월 시베리아로 추방했다. 이 과정에서 일부 화교 인사들이 체포되면서 많은 화교 상인들이 서울로 피난을 떠나, 각지 화교학교가 연이어 폐교를 했다. 1946년 8월 평양에 설립된 중국공산당 동북국(東北局)의 주 북한판사처는 북한측의 요청을 수용하여 북한 화교를 관리하기 위한 조직 설립에 나섰다. 그 결과 중공 간부와 북한 노동당 간부로 이루어진 북조선화교연합총회가 발족되었고, 각 지방에는 화교연합회가 개설되었다. 화교연합회의 주요한 업무는 화교들을 중공군 지원활동과 북한의 사회건설에 참여시키는 것이었는데, 실제로는 중공군 지원사업에 집중되었다. 화교연합회는 첫 사업의 하나로 화교학교를 재건하는 사업에 나섰으며, 화교학교는 연합회의 정책에 따라 친 중국공산당적인 사상 교육을 실시했다. 이러한 화교연합회 주도의 화교학교 재건과 교육은 1948년 9월부터 정규교육 강화에 힘을 쏟았다. 이 시기 화교연합회의 임무는 화교들을 북한의 사회건설에 참여시키는 데 주력하는 것으로 바뀌었으며, 북한측의 주도하에 각지에서 ‘북중학생연환회’가 개최되었다. 1948년 국공내전이 중공군에게 유리하게 전개되고, 북한에 파견됐던 중공 간부들이 속속 귀국하자 화교학교는 자금난과 교원 부족의 어려움을 겪게 되면서 화교연합회는 화교학교를 북한 정부에 이관하는 방안을 추진했다. 북한정부는 1949년 4월부터 화교학교의 관리를 화교연합회로부터 이양받았다. 북한 정부는 1949년 말까지 화교학교에 필요한 교육 시설을 정비함과 동시에 학교 내부의 제도 개혁을 단행했다. 1949년 9월에 조직된 ‘학부형회’와 ‘평의회’, ‘소년단’과 같은 조직이 새로 도입된 제도들이다. 교육방침은 화교 학생들을 북한의 사회건설에 참여시키기 위한 것으로 바뀌었다.

Cd_(1-x)Zn_xS/CdTe 이종접합 태양전지의 구조 및 전기적 특성에 관한 연구

송우창,이상교,심낙순,박종국,김원종 三陟大學校 2001 論文集 Vol.34 No.1

In this paper, the processing conditions and the various methods to improve the efficiency of the Cd1-xZnxS/CdTe solar cells were studied. Cd1-xZnxS films were grown by chemical bath deposition (CBD), which is a very attractive method for low-cost and large-area solar cells. To improve the electrical conductivity of Cd1-xZnxS films, thin indium films(10-40nm thickness) were evaporated on the surface of Cd1-xZnxS films. Experimental parameters such as indium film thickness, Zn mole fraction, and the annealing temperature in terms of structural and electrical properties of Cd1-xZnxS films were investigated. The diffusion process was carried out by heating the sample in air at 150-550℃ for 20 minute. The open circuit voltage of Cd1-xZnxS/CdTe solar cells increased due to reduced electron affinity difference between Cd1-xZnxS and CdTe films. However, the conversion efficiency of Cd1-xZnxS/CdTe solar cell decreased because of the higher series resistance(Rs) than CdS/CdTe solar cell. The series resistance and conversion efficiency of Cd1-xZnxS/CdTe solar cell were improved by using indium-doped Cd1-xZnxS films as windows layer. Cd1-xZnxS/CdTe solar cells fabricated with optimal conditions exhibited Voc=630㎷, Jsc=38.89㎃/㎠ and □=13.19%

CBD법으로 제작된 Cd₁-xZnxS 박막의 전기적 및 물리적 특성 분석

송우창,박종국,임윤희,이상교 三陟大學校 2001 論文集 Vol.34 No.1

Cd1_-xZn_xS films were grown by chemical bath deposition (CBD), which is a very attractive method for low-cost and large-area solar cells. To improve the electrical conductivity of Cd1_-xZn_xS films, thin indium films(10-40nm thickness) were evaporated on the surface of Cd1_-xZn_xS films. Experimental parpmeters such as indium film thickness, Zn mole fraction, and the annealing temperature in terms of structural and electrical properties of Cd1_-xZn_xS films were investigated. The diffusion process was carried out by heating the sample in air at 150-550℃ for 20 minute. X-ray diffraction patterns of Cd1_-xZn_xS films indicate that the minimum thickness and annealing temperature for the formation of an In2O3 surface layer, which act as a barrier preventing the outdiffusion of indium, are 20nm and 350℃, respectively. This layer allows indium diffusion into the Cd1_-xZn_xS films and results in an indium-doped Cd1_-xZn_xS films. As the indium film thickness is increased, the resistivity decreases and the lowest value(0.3Ω-㎝) is obtained for Cd1_-xZn_xS films annealed at 450℃ with 40nm of the thickness.

PET 기판 위에 증착된 ITO 투명전도막의 전기적ㆍ광학적 특성

송우창,Song, Woo-Chang 한국전기전자재료학회 2004 전기전자재료학회논문지 Vol.17 No.12

ITO films on PET substrate were prepared by DC magnetron sputtering method using powdery target with different deposition conditions. In addition, the electrical and optical properties were investigated. As the sputtering power and working pressure were higher, the resistvity of ITO films increased. The optical transmittance deteriorated with increasing sputtering power and thickness. As the working pressure increased, however, the optical transmittance improved at visible region of light. From these results, we could deposited ITO films with 8${\times}$10$^{-3}$ $\Omega$-cm of resistivity and 80 % of transmittance at optimal conditions.

열처리에 따른 Cd₁-xZnxS/In 박막의 광학적 및 전기적 특성 분석

송우창,이경호,심상흥,이상교,심재선,박종국 三陟大學校 2002 論文集 Vol.35 No.-

In this thesis, effects of the thickness of indium films and the annealing temperature on optical and electrical properties of chemically deposited CdZnS films for the efficiency of the Cd1-xZnxS/CdTesolar cells were investigated. To improve the electrical conductivity of Cd1-xZnxs films, thin indium films(10-4Onm thickness)were evaporated on the suface of Cd1-rZnxs films. Experimental parameters such as indium film thickness, Zn mole fraction, and the annealing temperature in terms of structural and electrical properties of Cd1-xZnxs films were investigated. The diffusion process was carried out by heating the sample in air at 150-550℃ for 20 minute As the indium film thickness is increased, the resistivity decreases and the lowest value(0.3 O -cm)is obtained for Cd1-xZnxs films annealed at 450℃ with 40nm of the thickness.

비파괴검사를 위한 PZT-5A 탐촉자에 관한 연구

임윤희,이상교,송우창 三陟大學校 1997 論文集 Vol.30 No.1

In this study, piezoelectric transducers were designed and manufactured using PZT-5A which had relatively high electromechanical coefficient. It was developed nondestructive testing system which was able to inspect automatically using stepping motors, PC-Lab, and PC-Scope. The optimum design conditions for NDT were presented and verified comparing PZT-5A probes with commercial probes. It was proved by simulation and experiments that Epoxy is a good material as matching and backing layers. The envelope was reduced 60% with matching layer and 76% with matching and backing layer. NDT was successfully carried out for aluminum test pieces. Distance error of PZT-5A probe was 2.8%.

대용량 회전기 고정자 절연재료의 절연층 분석

정의남,김상흥,송우창 三陟大學校 1997 論文集 Vol.30 No.1

In this study, after it is manufactured generator stator winding (500 MVA, 22kV) and it is investigated insulation layer of breakdown materials in air and hydrogen conditions The results are as follows; 1. Patial discharge of breakdown samples in hydrogen condition is inferior to one of break down samples in air condition. 2. In case of breakdown samples in hydrogen condition, microcrack wasn't grew masercrack. 3. It is difficult to distinguish the layer of insulation materials and the size of crack show about 10㎛

2상 HB형 Linear Stepping Motor의 정지정도 개선에 관한 연구

정의남,임윤희,이상교,이경호,송우창 三陟大學校 1999 論文集 Vol.32 No.1

A Linear Stepping Motor (LSM) can operate in an open loop control mode similarly to a rotary stepping motor. However, the LSM occur error between the actual mover position and the ideal position. In this paper, a position accuracy improvement method using an energy stored in winding inductance of the LPM is proposed.