130 nm-technology, 0.25 μm², 1T1C FRAM cell for SoC (system-on-a-chip)-friendly applications

We have successfully demonstrated a world smallest 0.25 μm ² cell 1T1C 64 Mb FRAM at a 130 nm technology node. This small cell size was achieved by scaling down a capacitor stack, using the following technologies: a robust glue layer onto the bottom electrode of a cell capacitor; 2-D MOCVD PZT technology, novel capacitor-etching technology; and a top-electrode-contact-free (TEC-free) scheme. The new FRAM cell is suitable for a mobile SoC (System-on-a-Chip) application. This is due to realization of four metal technology required for high-speed logic devices. As a result, the remanent polarization value of 32 μC/cm ² was achieved after full integration and the sensing window was evaluated to 370 mV at 85 °C, 1.3 V.