Ferroelectric tunnel junctions integrated on semiconductors with enhanced fatigue resistance
Ningchong Zheng, Jiayi Li, Haoying Sun, Yipeng Zang, Peijie Jiao, Cong Shen, Xingyu Jiang, Yidong Xia, Yu Deng, Di Wu, Xiaoqing Pan, Yuefeng Nie
Abstract
Oxide-based ferroelectric tunnel junctions (FTJs) show promise for nonvolatile memory and neuromorphic applications, making their integration with existing semiconductor technologies highly desirable. Furthermore, resistance fatigue in current silicon-based integration remains a critical issue. Understanding this fatigue mechanism in semiconductor-integrated FTJ is essential yet unresolved. Here, we systematically investigate the fatigue performance of ultrathin bismuth ferrite BiFeO 3 (BFO)–based FTJs integrated with various semiconductors. Notably, the BFO/gallium arsenide FTJ exhibits superior fatigue resistance characteristics (>10 8 cycles), surpassing the BFO/silicon FTJ (>10 6 cycles) and even approaching epitaxial oxide FTJs (>10 9 cycles). The atomic-scale fatigue mechanism is revealed as lattice structure collapse caused by oxygen vacancy accumulation in BFO near semiconductors after repeated switching. The enhanced fatigue-resistant behavior in BFO/gallium arsenide FTJ is due to gallium arsenide’s weak oxygen affinity, resulting in fewer oxygen vacancies. These findings provide deeper insights into the atomic-scale fatigue mechanism of semiconductor-integrated FTJs and pave the way for fabricating fatigue-resistant oxide FTJs for practical applications.