Li Changfang, Zhang Baolin, Qu Zhaozhu, Zhao Hongbin, Li Qixin, Zeng Zhaohui, Yang Rusen
Key Laboratory of New Processing Technology for Nonferrous Metal & Materials, Ministry of Education, Guangxi Key Laboratory of Optical and Electronic Materials and Devices, College of Materials Science and Engineering, Guilin University of Technology. Jian Gan Road 12, Guilin 541004, People's Republic of China.
Nanotechnology. 2021 Jan 13;32(14):145710. doi: 10.1088/1361-6528/abd3ca.
There are unrevealed factors that bring about the performance variations of resistive switching devices. In this work, Pt/CeO /Pt devices prepared by magnetron sputtering showed rectification in their asymmetrical current-voltage (I-V) curves during voltage sweeps. X-ray photoelectron spectroscopy showed that the deposited CeO film had an inhomogeneous composition, and more oxygen vacancies existed in CeO near the top electrode. The asymmetrical resistance change of the Pt/CeO /Pt devices can be explained by the presence of more charged oxygen vacancies in CeO near the top electrode, along with the Schottky conduction mechanism. This work reveals that the compositional inhomogeneity is inevitable in the magnetron sputtering of oxide targets like CeO and can be an important source of device-to-device and cycle-to-cycle variations of memristors.
存在一些未揭示的因素导致电阻开关器件的性能变化。在这项工作中，通过磁控溅射制备的Pt/CeO₂/Pt器件在电压扫描期间其不对称电流-电压（I-V）曲线呈现出整流特性。X射线光电子能谱表明，沉积的CeO₂薄膜具有不均匀的成分，并且在靠近顶部电极的CeO₂中存在更多的氧空位。Pt/CeO₂/Pt器件的不对称电阻变化可以通过靠近顶部电极的CeO₂中存在更多带电氧空位以及肖特基传导机制来解释。这项工作表明，在诸如CeO₂等氧化物靶材的磁控溅射中，成分不均匀是不可避免的，并且可能是忆阻器器件间和循环间变化的重要来源。
