Effects of ZrO 2 additions on the dielectric properties of CaCu 3 Ti 4 O 12

The dielectric spectra of CaCu 3 Ti 4 O 12 is characterized by a large permittivity ( ε r > 10 000 ) with only a weak dependence on temperature over the temperature range 200-400 K. In this work, doping with 0.1-1.0 wt% ZrO 2 has been shown to dramatically reduce the dielectric loss. At 0.5 wt% ZrO 2 , tan δ remains below 0.05 over the frequency range 50 Hz-30 kHz and is just 0.065 at 100 kHz. While there is some diminution of the permittivity ( ε r ≈ 5000 at 10 kHz) Zr-doped ceramics, exhibited very little bias dependence ( Δ C ∕ C 0 < 1 . 0 % up to 40 V). In summary, results suggest that ZrO 2 doping is an effective method for maintaining a high permittivity and low loss over a broad range in temperature, bias, and frequency.