ZnO thin films are of considerable interest because they can be customized by various coating technologies to have high electrical conductivity and high visible light transmittance. Therefore, ZnO thin films can be applied to various optoelectronic device applications such as transparent conducting thin films, solar cells and displays. In this study, ZnO rod and thin films are fabricated using aqueous chemical bath deposition (CBD), which is a low-cost method at low temperatures, and environmentally friendly. To investigate the structural, electrical and optical properties of ZnO for the presence of citrate ion, which can significantly affect crystal form of ZnO, various amounts of the citrate ion are added to the aqueous CBD ZnO reaction bath. As a result, ZnO crystals show a nanorod form without citrate, but a continuous thin film when citrate is above a certain concentration. In addition, as the citrate concentration increases, the electrical conductivity of the ZnO thin films increases, and is almost unchanged above a certain citrate concentration. Cu(In,Ga)Se2 (CIGS) solar cell substrates are used to evaluate whether aqueous CBD ZnO thin films can be applicable to real devices. The performance of aqueous CBD ZnO thin films shows performance similar to that of a sputter-deposited ZnO:Al thin film as top transparent electrodes of CIGS solar cells.

Abstract
1. 서 론
2. 실험 방법
3. 결과 및 고찰
4. 결 론
References

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• 오재영(한밭대학교 공과대학 신소재공학과) | Jae-Young Oh (Department of Materials Science and Engineering, Hanbat National University)
• 김재우(한밭대학교 공과대학 신소재공학과) | Jae Woo Kim (Department of Materials Science and Engineering, Hanbat National University)
• 이준수(한밭대학교 공과대학 신소재공학과) | Jun Su Lee (Department of Materials Science and Engineering, Hanbat National University)
• 최예솔(한밭대학교 공과대학 신소재공학과) | Yesol Choi (Department of Materials Science and Engineering, Hanbat National University)
• 홍기하(한밭대학교 공과대학 신소재공학과) | Ki-Ha Hong (Department of Materials Science and Engineering, Hanbat National University)
• 정중희(한밭대학교 공과대학 소재시스템공학과/한밭대학교 공과대학 신소재공학과) | Choong-Heui Chung (Department of Materials and Manufacturing Engineering, Hanbat National University/Department of Materials Science and Engineering, Hanbat National University) Corresponding author