Effect of crystallisation on fatigue in sol-gel PZT ferroelectric capacitors with reactively sputtered RuO2 electrode layers

Two new approaches for improving fatigue performance of sol-gel PZT based ferroelectric capacitors with RuO₂ electrodes are discussed. First, minimizing the time delay between RuO₂ sputtering and sol-gel PZT spinning increases the remanent polarisation of the crystallised PZT. Second, the use of thin (~5 nm) high-Ti PZT seed layer was found to be effective for improving fatigue performance. For an optimized seedlayer thickness, FECAPs with excellent fatigue characteristics (less than 10% decrease in P_r after 10¹¹ cycles) were obtained