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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 research, the forming-free CBRAM is realized by high pressure hydrogen annealing method (HPHA). With the structure of Cu/HfO2/TiN, the copper will be ionized by the hydrogen ion under the high pressure environment; meanwhile the copper ion will diffuse to the HfO2. Thus, the diffused copper ion can earlier form the precursor seed to generate the filament because of short migration distance. Besides, the characteristic of CBRAM is also improved, which can be explained by the experimental result and the proposed model. [ABSTRACT FROM AUTHOR]