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This study presents a comprehensive investigation of the impact of the deposition temperature on the HfxZr1−xO2 (HZO) ferroelectric layer of ferroelectric random access memory with TaN electrodes. This investigation mainly focuses on its electrical characteristics and compares the differences. It is revealed that the deposition temperature plays a crucial role in determining the crystal structure of HZO, which can exhibit a combination of tetragonal and orthorhombic phases or exist solely in one of the two phases. Furthermore, the grain size of HZO varies with the deposition temperature. These findings correspond well to the electrical measurement results, including leakage current, polarization, capacitance, and reliability tests. The study tracks the phase transition process during the operation of switching cycles when the phase transition process can be monitored as well. To better understand the observed differences, physical models that shed light on the underlying mechanisms affected by deposition temperature are proposed at the end of the article. [ABSTRACT FROM AUTHOR]

In this study, electrical measurements on ferroelectric random-access memory by prior x-ray irradiation are conducted. Compared with an unirradiated device, parameters such as current leakage and remnant polarization of the irradiated device were unexpectedly improved. Besides, better reliabilities including the number of endurance times and retention time have also been demonstrated. To clarify the underlying physical mechanism, the electrical properties are analyzed. The current–voltage curve (I–V) implies a change in the grain size in the ferroelectric layer (FL), and the capacitance–voltage curve (C – V) profile indicates that the FL undergoes a phase change during irradiation. Finally, according to the electrical results, a physical model is proposed as an explanation. [ABSTRACT FROM AUTHOR]