Switching quality of thin-film PZT ferroelectric capacitors

The switching quality of PZT thin-film ferroelectric capacitors was studied , using hysteresis and pulse switching measurements. The ferroelectric prop erties of epitaxial Pt/PZT/LSCO/MgO capacitors are strongly affected by the LSCO material. A strong deviation between hysteresis and pulse measurement s has been observed for one type of LSCO, corresponding to a strong relaxat ion of (oxygen-vacancy) space charge polarization. On the other hand, polyc rystalline Pt/PZT/Pt show very rectangular hysteresis loops with high P-r a nd pulse measurements reveal high speed switching and absence of rapid depo larization effects. These results prove the very high switching quality of Pt/PZT/Pt capacitors, required for their application as non-volatile memory elements.