Resistive Switching Behavior of Hafnium Oxide Thin Film Grown by Magnetron Sputtering

摘要:

采用磁控溅射法，以ITO/Glass为衬底，制备了具有电阻转变特性的HfO2薄膜。X射线光电子能谱（XPS）分析发现，薄膜中的Hf、O元素不成化学计量比，薄膜中可能存在大量氧空位。电学测试结果表明，HfO2薄膜表现出明显的双极电阻转变特性，并且表现出良好的可靠性（室温下可重复测试102次以上）和稳定的保持性能（0.5 V偏压下保持104 s以上），高低阻态比值达到104。基于XPS以及电学分析，薄膜的导电过程可用与氧空位相关的空间电荷限制电流模型解释

Abstract:

The HfO2 thin films with resistive switching behaviors were grown on indium tin oxide (ITO) /Glass substrates by radio-frequency (RF) magnetron sputtering method. The results of electrical tests indicate that HfO2 thin films show a bipolar resistive switching behavior. Using Ti as a buffer layer on the cathodal side of the memory cell, relatively reliable endurance (>2×102 cycles at 20 oC) and long data retention time (>104s at 20 oC) have been demonstrated, and the high-resistance to low-resistance ratio can reach 104. Based on the electrical property test results, the phenomena can be correlated with oxygen-vacancy-related traps. Space charge limited current (SCLC) mechanism is believed to be the reason for the resistive switching from the OFF state to the ON state