Microwave dielectric properties of a new ceramic system NdNbO4 with CaF2 addition

► A new ceramic system NdNbO4 was composed by conventional solid-state route. ► Microwave dielectric properties of NdNbO4 with CaF2 addition were investigated. ► The 2.0 wt.% CaF2-doped NdNbO4 ceramics showed a large increase in the Q × ƒ. ► The relationship between microstructure and properties was investigated.