Lithium manganese oxide (LiMn2O4) cathode thin films were deposited on a Si substrate by radio frequency (RF) magnetron sputtering. The films were annealed within the range 400 to 700 oC for 2 h in O2. Structure and surface morphology of the films were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Elemental analysis was conducted by energy dispersive spectroscopy (EDS). The degree of crystallization in the films increases with annealing temperature. A phase transformation from the amorphous to the crystalline phase is apparent at around 600 oC. Films annealed at 700 oC exhibit characteristic XRD peaks with a predominant (111) orientation representing cubic spinel structure. The lattice parameter is 6.694 Å for the 700 oC annealed film. The grain size gradually increases with annealing temperature, as evident from the SEM images.

Keywords: LiMn2O4 thin film, Lithium battery, RF magnetron sputtering.