Effect of Annealing in ITO Film Prepared at Various Argon-and-Oxygen-Mixture Ratios via Facing-Target Sputtering for Transparent Electrode of Perovskite Solar Cells

Abstract

Normal perovskite solar cells (PSCs) consist of the following layers: transparent electrode, electron-transport layer (ETL), light-absorbing perovskite layer, hole-transport layer (HTL), and metal electrode. Energy, such as electricity, is produced through light absorbance and electron–hole generation/transport between two electrode types (metal film and transparent conducting film). Among stacked layers in a PSC, the transparent electrode plays the high-performance-power-conversion-efficiency role. Transparent electrodes should have high-visible-range transparency and low resistance. Therefore, in this study, we prepared indium tin oxide (ITO) films on a glass substrate by using facing-target sputtering without substrate heating treatment and investigate the heating-treatment effect on the ITO-film properties for perovskite solar cells (PSCs). Moreover, we fabricated PSCs with ITO films prepared at various oxygen flows during the sputtering process, and their energy-conversion properties are investigated.