Breakdown-limited endurance in HZO FeFETs: Mechanism and improvement under bipolar stress

Breakdown is one of main failure mechanisms that limit write endurance ferroelectric devices using hafnium oxide-based materials. In this study, we investigate the gate current and breakdown characteristics Hf0.5Zr0.5O2/Si field-effect transistors (FeFETs) by carrier separation measurements to analyze electron hole leakage currents during time-dependent dielectric (TDDB) tests. Rapidly increasing substrate stress-induced (SILC)-like can be observed before insulator FeFETs. This apparent degradation under voltage stress recovered time-to-breakdown significantly improved interrupting TDDB test with pulses opposite polarity, suggesting defect redistribution, rather than generation, responsible for trigger hard breakdown.