FeRAM using Anti-ferroelectric Capacitors for High-speed and High-density Embedded Memory

This paper demonstrates industry-best hafnium-based FeRAM performance and reliability by showing (i) read/write speed scaled down to ~2ns, (ii) read/write endurance beyond 10 ¹² cycles, and (iii) tail-bit variations of scaled capacitors working at $4\sigma$ across a 300mm wafer at elevated temperature, by switching anti-ferroelectric (AFE) capacitors at −1.6V and 1.2V. Furthermore, a physics-based multi-domain compact circuit model is developed for AFE capacitors to describe FeRAM operations. Array-level circuit simulations show that FeRAM is less vulnerable to disturb through parasitic capacitor coupling due to the small amount of polarization charge change $(\Delta P)$ relative to its high remanent polarization $(P_{r})$ . Finally, high yield in a capacitor-array with no significant degradation in retention well over 10s and a healthy memory window (MW) under 1ms disturb 20% of $V_{write}$ at elevated temperature is shown, paving way for AFE-based FeRAM toward the next generation high-speed and high-density embedded memory.