Deep Insights into the Failure Mechanisms in Field-cycled Ferroelectric Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub> Thin Film: TDDB Characterizations and First-Principles Calculations
Wei Wei, Weiqiang Zhang, Fei Wang, Xiaolei Ma, Qianwen Wang, Pengpeng Sang, Xuepeng Zhan, Yuan Li, Lu Tai, Qing Luo, Hangbing Lv, Jiezhi Chen
Abstract
To address the failure mechanisms in ferroelectric devices, this work presents a systematical study on Hf <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</inf> Zr <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> -based ferroelectric memory. Firstly, by detail electrical characterizations of P-V and C-V curves in field-cycled devices, three dominant failure modes can be well distinguished. Then, by combining the TDDB measurements and first-principles calculations, it is found that, 1) the annealing temperature has large impacts on the initial defects concentrations while weakly affect the trap generation rate; 2) the breakdown paths take place mainly in the amorphous regions, which could generate reconfigurable filaments and cause RRAM properties; 3) temporary recovered ferroelectricity during cycling can be explained by considering the unstable breakdown paths generated at the grain boundary.