The effects of inequivalent La3+ introduction on the structure and dielectric properties of SrTiO3 ceramic at microwave range

Inequivalent La3+ is firstly utilized to modify the microwave dielectric properties in SrTiO3 ceramic system. For the general composition of Sr1-xLa2x/3TiO3 (0 ≤ x ≤ 1), the effects of La3+ introduction on the phase transition and structural changes are systematically investigated. The correlation between A-site ordering degree and dielectric loss in microwave range is established, and the temperature coefficient of resonant frequency is also dramatically improved. When x = 0.945, excellent dielectric properties of εr ∼89.3, Qf ∼15243 GHz (@4.3 GHz) and τf ∼ 160 ppm/°C are obtained, making it potential to meet the application requirements of 5G technologies.