Ferroelectric and Antiferroelectric Phenomenon in Lanthanum Doped Hafnium Based Thin Films

Hafnium lanthanum oxide (HLO) thin film, known for their excellent ferroelectric properties, have emerged as a promising strategy for future non-volatile memory (NVM) applications. In this letter, we systematically investigate the impact of Zr doping on the ferroelectric behavior and endurance of HLO thin films for the first time. Through controlled Zr incorporation, we observe significant enhancement in ferroelectric, dielectric and endurance performance. Specifically, wake-up free Zr:HLO thin films with Zr~50% content exhibit a remarkable double remnant polarization
$2{P}_{\text {r}}\sim 54.5 ~\mu \text{C}$
/cm2 with a coercive field (
${E}_{\text {c}}{)}$
of 1.3 MV/cm after 108 cycles electric field training. Furthermore, Zr:HLO with 80%Zr content demonstrate remarkable (quasi-) antiferroelectric behavior and perform an improved endurance performance (109 cycles with
$2{P}_{\text {r}}\sim 21.8 ~\mu \text{C}$
/cm2). These findings underscore the potential of proposed Zr:HLO ferroelectric thin film devices tailored with Zr doping for advanced memory technologies.