Investigating Ferroelectric Minor Loop Dynamics and History Effect—Part I: Device Characterization

Doped HfO2-based ferroelectric field-effect transistor (FeFET) is being actively explored as an emerging nonvolatile memory device with the potential for in-memory computing. In this work, we identify a new challenge of ferroelectric partial switching, namely “history effect” in minor loop dynamics. We develop a testing protocol to experimentally measure different transition paths in both ferroelectric capacitors (FeCap) and 28-nm high-k metal-gate (HKMG) FeFET in Part I. The measurement results suggest that the intermediate states programming condition depends on the prior states that the device has gone through, and the condition may vary even when the transition occurs between the same starting and ending states. In Part II, a physics-based phase-field multidomain switching model is used to understand the origin of the history effect.