Effects of sintering parameters and Nd doping on the microwave dielectric properties of Y2O3 ceramics

Y2O3 ceramics with good dielectric properties were prepared via co-precipitation reaction and subsequent sintering in a muffle furnace. The effects of Nd doping and sintering temperature on microwave dielectric properties were studied. With the increase in sintering temperature, the density, quality factor (Q x f), and dielectric constant (epsilon(r)) values of pure Y2O3 ceramics increased to the maximum and then gradually decreased. The Y2O3 ceramics sintered at 1500 degrees C for 4 h showed optimal dielectric properties: epsilon(r) = 10.76, Q x f = 82, 188 GHz, and tau(f) = 54.4 ppm/degrees C. With the addition of Nd dopant, the Q x f values, epsilon(r) and tau(f) of the Nd: Y2O3 ceramics apparently increased, but excessive amount degraded the quality factor. The Y2O3 ceramics with 2 at% Nd2O3 sintered at 1460 degrees C displayed good microwave dielectric properties: epsilon(r) = 10.4, Q x f = 94, 149 GHz and tau(f) = -46.2 ppm/degrees C. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.