High optical transmittance and anomalous electronic transport in flexible transparent conducting oxides [formula omitted] thin films

Abstract

Wide bandgap semiconducting perovskite La:BaSnO3 is a promising candidate for next-generation transparent conducting oxides due to its high electron mobility and excellent oxygen stability. In this work, in order to realize flexible optoelectronics, an epitaxial growth of Ba0.96La0.04 SnO3 (BLSO) film on a flexible mica via van der Waals epitaxy is established. The high quality heteroepitaxy and crystallinity of BLSO films are confirmed by a combination of X-ray diffraction and atomic force microscopy. Results show that the flexible BLSO films not only retain a high transmittance of more than 85% in the visible region under unbending conditions, but also exhibit a remarkable transmittance of 90% under bending conditions. Due to the fixed lattice mismatch and misfit strain, an anomalous electronic transport behavior, showing as a continuous enhancement of resistivity dependence on the decreasing temperatures from high to low, was observed for all BLSO films. Although the resistivity of flexible BLSO films is a slight larger than that of growth on rigid counterparts, the resistivity of 7–10 mΩ cm is also satisfied with actual application for optoelectronic devices at room-temperature. Our study marks that the technological advancements toward realizing flexible optoelectronics are promising by utilizing perovskite oxides La-doped BaSnO3 and mica substrate.