Preparation of Hexagonal SrMnO₃ High-Quality Target for Magnetron Sputtering

In recent years, the optical behavior of complex oxides are being increasingly used in light-harvesting applications. Perovskites are promising candidates for photovoltaic, photocatalytic, and optoelectric applications because of tunable band gaps and other unique properties such as fer-roelectricity To study the optical behavior of ferromagnetic-ferroelectric oxides, SrMnO₃ (SMO₃) targets intended for use in magnetron sputtering were prepared using SrCO₃ (99.99%) and Mn₂O₃ (99.99%) powders by a two-step solid reaction method. Experiments were performed at various temperatures to determine the optimum calcination temperature of the SMO₃ powder (1000 °C) and optimum sintering temperature of the prepared target (1300 °C), in an effort to optimize the preparation process of the target at the laboratory scale and reduce the cost of the target by more than 20-fold. Samples of the ground powder were calcined at 800, 1000, 1200, and 1300 °C for 10 h, and the resultant targets were pressed into 1 -in molds after grinding and subsequently sintered at the same temperatures at which the corresponding powders were calcined, i.e., at 800, 1000, 1200, and 1300 °Cfor 48 h. The microcrystalline state of the powders was observed by scanning electron microscopy. The prepared targets were analyzed by X-ray diffraction, and the results were compared with the powder diffraction file card of hexagonal SMO₃ to determine the optimum calcination temperature and sintering temperature of the powder formulation. Finally, the Vickers hardness values of the targets were measured, and the optimum target preparation process was determined.