Ferroelectric properties of Pb(Zr,Ti)O3 thin films until 40 GHz

The radio frequency characterization of Cu/TiN/Pb(Zr,Ti)O-3 stack on glass is performed using coplanar transmission lines. A dielectric relaxation is evidenced around 10 GHz by the correlated decrease in the dielectric constant K together with the dielectric losses increase versus frequency. This phenomenon is attributed to domain wall relaxation. The ferroelectric nature of Pb(Zr,Ti)O-3 (PZT) thin films is observed until 40 GHz with a hysteresis curve of K versus dc bias. The high K value (K similar to 1200) combined with a high tunability (similar to 35%) and moderate losses (similar to 1%) suggest that PZT films could be well suited for tunable devices for frequencies lower than 5 GHz.