Exploring the Thermal Stability and Mechanical Endurance of a Titanium-Doped Germanium Antimony Thin Film for Flexible Nonvolatile Memory Application

The inherent limitations of silicon-based memory lie in rigid structural constraints and poor mechanical bendability, which have stimulated the growing research interest in exploring flexible memory technologies. We proposed the enhanced flexibility Ti-doped Ge₁Sb₉ phase-change materials, which were deposited on a polyimide substrate by the magnetron sputtering method. The thermal stability, mechanical bendability, surface morphology, and electrical properties of the Ti-doped Ge₁Sb₉ materials were systematically investigated. Compared with the pure Ge₁Sb₉, Ti-doped Ge₁Sb₉ films possess superior thermal stability and mechanical bendability. The film resistance remains almost unchanged after multiple bending cycles, indicating the excellent robust self-healing characteristic. This may be due to the more uniform stress distribution within the material, inhibiting the permanent structural damage and maintains resistance stability. Flexible phase-change memory devices based on Ti_0.05(Ge₁Sb₉)_0.95 films were fabricated, which can complete the reliable SET/RESET operations in both flat and bending states. All the results confirm the potential of the Ti-doped Ge₁Sb₉ film for flexible memory application, featuring the outstanding thermal stability, remarkable mechanical robustness, stable electrical switching, and low power consumption.