Effects of (Li0.5Nd0.5)2+ on the phase evolution, Raman spectra and microwave dielectric properties in CaO–Nd2O3–TiO2 ceramic

Abstract

Abstract The rapid advancement of mobile communications technology is imposing greater demands on electronic components. Microwave dielectric ceramics with a high dielectric constant ( ϵ r ) are crucial for the miniaturization and integration of microwave devices. Herein, The perovskite-structured (Ca 0.61 Nd 0.26 ) 1− x (Li 0.5 Nd 0.5 ) x TiO 3 (0 ⩽ x ⩽ 0.8) microwave dielectric ceramics with high ϵ r value were prepared by solid-state reaction method. The results demonstrated that the ϵ r value reached its peak at x = 0.6, which was influenced by the bond valence at B-sites. The τ f and Q × f values decreased with increasing x value. Doping (Li 0.5 Nd 0.5 ) 2+ at A-sites led to an increase in the full width at half maximum of Raman peaks, indicating higher internal loss. A high dielectric constant and temperature-stable (Ca 0.61 Nd 0.26 ) 0.27 (Li 0.5 Nd 0.5 ) 0.73 TiO 3 ceramic can be sintered with good microwave dielectric properties of ϵ r = 129.4, Q × f = 2,787 GHz, and τ f = +1.9 ppm/°C.