Flexible and transparent TiO 2 /Ag/ITO multilayer electrodes on PET substrates for organic photonic devices
- PDF / 350,684 Bytes
- 6 Pages / 584.957 x 782.986 pts Page_size
- 90 Downloads / 234 Views
Jun Ho Kim Department of Materials Science and Engineering, Korea University, Seoul 136-713, Korea
Han-Kyeol Lee, Jin-Young Na, and Sun-Kyung Kim Department of Applied Physics, Kyung Hee University, Gyeonggi-do 446-701, Korea
Jeong Hwan Lee School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 440-746, Korea
Sang-Woo Kim SKKU Advanced Institute of Nanotechnology (SAINT), Center for Human Interface Nanotechnology (HINT), Sungkyunkwan University (SKKU), Suwon 440-746, Korea
Young-Zo Yoo Duksan Hi-Metal Co. Ltd., Yeonam-dong, Buk-gu, Ulsan 683-804, Korea
Tae-Yeon Seonga) Department of Materials Science and Engineering, Korea University, Seoul 136-713, Korea; and Department of Nanophotonics, Korea University, Seoul 136-713, Korea (Received 30 December 2014; accepted 30 March 2015)
We report on the formation of highly flexible and transparent TiO2/Ag/ITO multilayer films deposited on polyethylene terephthalate substrates. The optical and electrical properties of the multilayer films were investigated as a function of oxide thickness. The transmission window gradually shifted toward lower energies with increasing oxide thickness. The TiO2 (40 nm)/Ag (18 nm)/ITO (40 nm) films gave the transmittance of 93.1% at 560 nm. The relationship between transmittance and oxide thickness was simulated using the scattering matrix method to understand high transmittance. As the oxide thickness increased from 20 to 50 nm, the carrier concentration gradually decreased from 1.08 1022 to 6.66 1021 cm3, while the sheet resistance varied from 5.8 to 6.1 X/sq. Haacke’s figure of merit reached a maximum at 40 nm and then decreased with increasing oxide thickness. The change in resistance for the 60 nm-thick ITO single film rapidly increased with increasing bending cycles, while that of the TiO2/Ag/ITO (40 nm/18 nm/40 nm) film remained virtually unchanged during the bending test. I. INTRODUCTION
Transparent conducting electrodes (TCEs) are technologically important because of their applications in optoelectronics, flat panel displays, and solar cells.1–3 To maximize the performance of such devices, TCEs ought to have high transmittance in the visible spectrum and low resistance. Sn-doped indium oxide (ITO) is the most popular TCE used in optoelectronic applications because of its low resistivity and high transmittance in the visible spectrum.4 However, indium is a rare and expensive metal. So, there is a great demand for developing new transparent conducting oxides that can replace ITO. In this regard, a wide variety of oxides have been hitherto Contributing Editor: Gary L. Messing a) Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2015.100 J. Mater. Res., Vol. 30, No. 10, May 28, 2015
investigated.2,5–7 In addition, dielectric/metal/dielectric (D/M/D) multilayers have also been actively studied to realize both low resistivity and high transmittance in the visible spectrum. Ag is generally used as the middle layer for D/M/D multilayers since Ag thin films (,20 nm
Data Loading...
