(1-x)BaTiO3-x(Bi0.5Na0.5)TiO3 (0.01≤x≤0.10) ceramics were fabricated with muffled sintering by a modified synthesis process. Their positive temperature coefficient of resistivity (PTCR) characteristics were investigated systematically. All specimen showed a perovskite structure with a tetragonal symmetry. Both the lattice parameter of a and c axes were slightly decreased with increasing (Bi0.5Na0.5)TiO3 (BNT) content. Grain growth was achieved when the incorporated BNT was increased to 6 mol% and the inhibition of grain growth is considered to be due to the appearance of Ba vacancy (V"(Ba)) in the (1-x)BaTiO3-x(Bi0.5Na0.5)TiO3 (0.08≤x). With 4 mol% BNT addition, room temperature resistivity decreased to 48 Ω·㎝ and a resistivity jump (ρmax/ρmin) was as high as 1.1×10(4), respectively. Curie temperature was also increased to 171˚C with increasing BNT content.
