Experimental Investigation of Thermal Annealing and Ferroelectric Capacitor Area Effects for Hafnium-Zirconium Oxide Devices

Abstract

In this study, we reveal that the thermal budget of post-metal annealing not only determines the formation of the ferroelectric phase and dipole domain but also the film quality of the gate stack in a metal-ferroelectric-metal capacitor. The higher leakage current caused by defect traps or grain boundaries within a gate stack would influence the stability of the ferroelectric domain switching. Furthermore, the ferroelectric domain switching and polarization current also depend on the ferroelectric capacitor area. We observe that a HfAlO ferroelectric capacitor can dominate the transfer characteristics of a p-type SnO thin-film transistor through the modulation of series capacitance in the gate stack based on a one-transistor one-capacitor series configuration. According to experimental results, the memory hysteresis window can be improved significantly with the area scaling due to the improvement of capacitance matching accuracy.

Oxygen scavenging of HfZrO2-based capacitors for improving ferroelectric properties

“…The capacitor with scavenging showed outstanding performances compared to the capacitor without scavenging as well as other previous MFIS structures. 32,49–53…”

Functional Ferroic Materials, Films and Devices

“…Therefore, these materials are technologically important for many applications (e.g., ferroelectric memory, sensor and energy storage devices), and they have thus received continuous attention [2]. For example, Hsu et al found that the ferroelectric capacitor can dominate the transfer characteristics of a p-type SnO thin-film transistor through the modulation of series capacitance in the gate stack based on a one-transistor one-capacitor series configuration [3].…”