Imprint issue during retention tests for HfO₂-based FRAM: An industrial challenge?

For ferroelectric random access memory (FRAM) with HfO 2-based materials, the wake-up effect and imprint have to be limited. Here, electrical behavior of different samples is investigated during retention tests on woken-up at room temperature. Retention properties are compared or without alternations voltage pulses opposite signs. First, alternations, oscillates between two values that believed too high for reading operation industrial FRAM memories. This oscillation not sole cause remanent polarization loss. Second, loss appear closely linked. Finally, fitting models tested: first one follows a power law t ? n second corresponds stretched exponential exp ( / ? ? ). The data cannot fitted by all, while can fit after > 100 s. In fact, model highlights reduction separated into least parts: short period elapsed time long time. origins this two-part discussed.