title: Roll-to-Roll sputtered ITO/Cu/ITO multilayer electrode for flexible, transparent thin film heaters and electrochromic applications.
abstract: We fabricate high-performance, flexible, transparent electrochromic (EC) films and thin film heaters (TFHs) on an ITO/Cu/ITO (ICI) multilayer electrode prepared by continuous roll-to-roll (RTR) sputtering of ITO and Cu targets. The RTR-sputtered ICI multilayer on a 700 mm wide PET substrate at room temperature exhibits a sheet resistance of 11.8 Ω/square and optical transmittance of 73.9%, which are acceptable for the fabrication of flexible and transparent EC films and TFHs. The effect of the Cu interlayer thickness on the electrical and optical properties of the ICI multilayer was investigated in detail. The bending and cycling fatigue tests demonstrate that the RTR-sputtered ICI multilayer was more flexible than a single ITO film because of high strain failure of the Cu interlayer. The flexible and transparent EC films and TFHs fabricated on the ICI electrode show better performances than reference EC films and TFHs with a single ITO electrode. Therefore, the RTR-sputtered ICI multilayer is the best substitute for the conventional ITO film electrode in order to realize flexible, transparent, cost-effective and large-area EC devices and TFHs that can be used as flexible and smart windows.
authors.affiliation: Kyung Hee University, Department of Advanced Materials Engineering for Information and Electronics, 1 Seocheon, Yongin, Gyeonggi-do 446-701, Republic of Korea.
authors.forename: Sung-Hyun
authors.initials: SH
authors.lastname: Park
authors.affiliation: Kyung Hee University, Department of Advanced Materials Engineering for Information and Electronics, 1 Seocheon, Yongin, Gyeonggi-do 446-701, Republic of Korea.
authors.forename: Sang-Mok
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Kyung Hee University, Department of Advanced Materials Engineering for Information and Electronics, 1 Seocheon, Yongin, Gyeonggi-do 446-701, Republic of Korea.
authors.forename: Eun-Hye
authors.initials: EH
authors.lastname: Ko
authors.affiliation: IPCE, Materials Research Center, School of Energy, Materials, and Chemical Engineering, Korea University of Technology and Education, Cheonan 31253, Republic of Korea.
authors.forename: Tae-Ho
authors.initials: TH
authors.lastname: Kim
authors.affiliation: IPCE, Materials Research Center, School of Energy, Materials, and Chemical Engineering, Korea University of Technology and Education, Cheonan 31253, Republic of Korea.
authors.forename: Yoon-Chae
authors.initials: YC
authors.lastname: Nah
authors.affiliation: Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology, Yuseong-gu, Daejeon 34114, Republic of Korea.
authors.forename: Sang-Jin
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology, Yuseong-gu, Daejeon 34114, Republic of Korea.
authors.forename: Jae Heung
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Kyung Hee University, Department of Advanced Materials Engineering for Information and Electronics, 1 Seocheon, Yongin, Gyeonggi-do 446-701, Republic of Korea.
authors.forename: Han-Ki
authors.initials: HK
authors.lastname: Kim