Formation of Flexible and Transparent Indium Gallium Zinc Oxide/Ag/Indium Gallium Zinc Oxide Multilayer Film

Abstract

In this study, the electrical, optical, and bending characteristics of amorphous indium gallium zinc oxide (IGZO)/Ag/IGZO (39 nm/19 nm/39 nm) multilayer films deposited on polyethylene terephthalate (PET) substrate at room temperature were investigated and compared with those of Sn-doped indium oxide (ITO) (100 nm thick) films. At 500 nm the ITO film transmitted 91.3% and the IGZO/Ag/IGZO multilayer film transmitted 88.8%. The calculated transmittance spectrum of the multilayer film was similar to the experimental result. The ITO film and IGZO/Ag/IGZO multilayer film, respectively, showed carrier concentrations of 1.79 x 10(20) and 7.68 x 10(21) cm(-3) and mobilities of 27.18 cm(2)/V s and 18.17 cm(2)/V s. The ITO film had a sheet resistance of 134.9 Omega/sq and the IGZO/Ag/IGZO multilayer film one of 5.09 Omega/sq. Haacke's figure of merit (FOM) was calculated to be 1.94 x 10(-3) for the ITO film and 45.02 x 10(-3) Omega(-1) for the IGZO/Ag/IGZO multilayer film. The resistance change of 100 nm-thick ITO film was unstable even after five cycles, while that of the IGZO/Ag/IGZO film was constant up to 1000 cycles.