Mechanism for slow programming in advanced low-voltage, high-speed ferroelectric memory

Polarization charge loss in PZT ferroelectric memory under low-voltage and high-speed operation is observed. The polarization loss worsens significantly at low operation voltage and elevated temperature. This effect significantly reduces the sensing margin and causes severe reliability issues for advanced ferroelectric memory, particularly at low-voltage application. This polarization loss is attributed to slowing-down of polarization switching caused by band bending from Schottky potential at the electrode/ferroelectric interface. A solution to eliminate the polarization loss is proposed and verified.