Annealing behavior of ferroelectric Si-doped HfO2 thin films

• Isochronal anneals at 700–900 °C were applied to 3 compositions of Si-doped HfO2.
• Three compositions of Si-doped HfO2 underwent isothermal anneals for 5–60 s.
• Remanent polarization, leakage current, and breakdown were correlated with anneals.
• Antiferroelectric-like → ferroelectric transition was observed from 700 to 900 °C anneals.
• Three cases of cycling behavior with dynamic hysteresis currents are demonstrated.

Rapid thermal annealing of 10 nm thick Si-doped HfO2 thin films was performed to study the influence of isochronal and isothermal anneals on the ferroelectric and electrical properties of thin film metal-ferroelectric-metal capacitors. The anneal temperature and time dependence of the ferroelectric Si-doped HfO2 thin films was investigated by applying 700 °C–900 °C rapid thermal anneals for 5 s–60 s durations. An antiferroelectric-like to ferroelectric transition with increasing anneal temperature is observed in the Si-doped HfO2 thin films. The electrical properties of Si-doped HfO2 thin films exhibit a strong temperature dependence and a significant time dependence for the temporal range studied in this work. The breakdown field in the ferroelectric HfO2 thin films ranges from 3.8–5.3 MV/cm depending on the anneal temperature and atomic layer deposition cycle ratio. The remanent polarization, breakdown field, and leakage current is discussed in the context of the Si-doping, anneal temperature, and anneal time. Dynamic hysteresis currents are used to illustrate specific cases of the cycling behavior for the Si-doped HfO2 thin film capacitors.