BEOL-Compatible Annealing-Free HfxZr1-xO2 Ferroelectric Device and Investigation of Cycle-Dependent Evolution Mechanisms

This work focuses on the performance optimization and cycle-dependent evolution mechanisms of low-temperature anneal-free hafnium-based ferroelectric devices. By modulating oxygen plasma power, effective synthesis of ferroelectric o-phase was achieved at processing temperatures ≤280 °C without the need for additional annealing process, compatible with CMOS back-end-of-line (BEOL) technology. The HfxZr1-xO2 (HZO) film fabricated at 50-W power demonstrates a remarkable 2Pr of $50~\mu $ C/cm2 and can withstand 1010 polarization cycles without dielectric breakdown, exhibiting the best overall performance. Through combined macroscopic electrical characterization and microscopic polarization switching dynamics analysis, this work reveals a cycle-dependent evolution mechanism of ferroelectric properties and proposes a defect dynamic evolution model for anneal-free films. These results establish a foundational framework for designing next-generation embedded ferroelectric memories with low-temperature compatibility and ultrahigh reliability.