Lithium cobalt oxide crystallization on flexible polyimide substrate

Abstract : This work reports the fabrication and characterization of lithium cobalt oxide films (LiCoO$_2$) on flexible Kapton$^R$ substrate. LiCoO$_2$ is commonly used as cathode of lithium microbatteries but needs an annealing of 700°C, which is not compatible with most flexible substrates. LiCoO$_2$ films were deposited by reactive RF sputtering followed by an annealing process at 400 °C for 1 h in vacuum and air atmospheres both in silicon and Kapton$^R$ substrates. Raman spectroscopy, X-ray diffraction patterns and scanning electron microscopy images were used to evaluate samples crystallinity and morphology. Films fabricated in Kapton$^R$ and silicon substrates were compared.