Study of the bipolar resistive-switching behaviors in Pt/GdOx/TaNx structure for RRAM application



The bipolar resistive switching (RS) behaviors in Pt (top)/GdOx/TaNx (bottom) memory cells were investigated systematically for RRAM applications. Compared to that of the memory cells in Pt/GdOx/Pt structure showing unipolar switching behaviors, the memory cells in Pt/GdOx/TaNx structure with bipolar switching behaviors show better switching properties, such as better switching reliability, enhanced cycling endurance, improved low resistive state value and more uniform RS parameters. The composition and chemical bonding states of the prepared GdOx and TaNx films were analyzed by X-ray photoelectron spectroscopy to elucidate the underlying resistive switching mechanisms for Pt/GdOx/TaNx structures. The results show that both the oxygen vacancies in the GdOx film and the interfacial TaON layer formed between the dielectric GdOx film and the TaNx bottom electrode play important roles in the RS performance improvement.