On the effect of PbO and PbO2 content on microwave behaviour of PZT-derived MMIC capacitors

In this work, sputtered PZT thin films with differing PbO and PbO₂ contents were used to investigate the effect of lead compositions on microwave properties of PZT capacitors. Capacitors with five different electrode areas were fabricated, and on-wafer characterization process was performed between 100 MHz to 20 GHz. S₁₁ was measured and parasitic elements were de-embedded to evaluate the capacitance, relative permittivity and loss tangent. Capacitive behavior was proved whereby the capacitance was proportional to the electrode area and the film permittivity. The dependence of permittivity on frequency was also studied. The results indicate that the permittivity, and hence the capacitor performance, were highly dependent on the PbO and PbO₂ content.