Pulse-Width-Dependent Imprint Effect in Ferroelectric Hf0.5Zr0.5O2 Capacitors

초록

This work investigates imprint effect in ferroelectric Hf0.5Zr0.5O2 (HZO) capacitors and its dependence on pulse conditions. Extending the read time facilitates dipole reorientation and promotes polarization switching, even at reduced voltages. Building on this insight, applying longer re-write pulses is found to release pinned domains and significantly alleviate imprint, thereby improving retention. The extracted device lifetime increases dramatically, from similar to 10 h (5 mu s re-write) to similar to 10 years (1 ms re-write). These results indicate that short pulses remain essential for accurate imprint evaluation, while longer pulses can serve as a recovery strategy that suppresses imprint and extends device lifetime. Overall, this study establishes practical guidelines for imprint testing and provides a pathway to address imprint-related reliability challenges in Hf-based ferroelectric devices.

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