Preparation and microstructure of BaTiO₃ thin films by RF magnetron sputtering

Abstract The preparation of high-quality films is a key challenge in building high-performance electro-optic modulators and achieving ultra-high-speed optical communication. In this research, we used magnetron sputtering to precisely prepare BaTiO 3 thin films on SrTiO 3 substrates, and systematically studied the effects of process parameters on their crystallinity and microstructure. Under optimized process conditions—a sputtering power of 60 W, chamber pressure of 1.0 Pa, argon-oxygen ratio of 6:1, substrate temperature of 350 °C, and a sputtering duration of 60 minutes—the thin film exhibited a <200> preferred orientation, a grain size of 38.7 nm, X-ray diffraction <200> half-peak full width is 0.288°, and demonstrated high crystalline quality and microstructural order. This research provides scientific evidence for the preparation of high-performance electro-optic modulator materials and has important academic and practical value for the development of Si-based photonic integration technology.