Ferroelectric tunnel junctions integrated on semiconductors with enhanced fatigue resistance

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.