Non-Volatile Ferroelectric FETs Using 5-nm Hf0.5Zr0.5O2 With High Data Retention and Read Endurance for 1T Memory Applications

FeFETs with 5-nm-thick Hf0.5Zr0.5O2 (HZO) have been demonstrated in memory operations for the ON/OFF current ratio > 10(4) at zero gate voltage and a memory window (MW) of 0.6-0.7 V. A gradual transition of the ferroelectricity with an increasing crystallization temperature for the gate-last process was presented. The excellent data retention are the similar to 2x10(4) ON/OFF ratio and 0.67V extrapolated to ten years with VP/E = +/- 4.8 V. The MW remains > 0.2 V after 106 cycles for read and vanisheswith cycles of 10(3)-10(4) for write, which is the bottleneck for ferroelectric (FE)-type memories. The mechanism of retention and endurance is discussed. The characteristic of this letter is an unaffected coercive-field (similar to 1 MV/cm) with scaling FE-HZO down to 5-nm thickness, which is beneficial for reducing the operation voltage. A comparable performance with thick HZO (> 5 nm) on high data retention and endurance with low voltage for read is achieved. The ultrathin FE layer proposes a realistic emerging memory for 1T architecture.