Super-flexibility in Freestanding Single-Crystal SrRuO₃ Conductive Oxide Membranes

Abstract

Conductive\noxides are considered to be attractive electrodes in\nelectronic applications such as piezoelectric, energy storage, and\nsemiconductor devices due to their good electrical conductivity and\ncompatibility with other functional oxides. However, conductive oxides\nare generally brittle, which limits their applications in flexible\nelectronic devices. Here, freestanding single-crystal SrRuO₃ membranes have been prepared by etching a sacrificial layer. The\nprepared membranes can be buckled into sinusoidal shapes of different\nsizes, indicating that the membranes are super-flexible. The mechanical\nproperties were performed on the well-strained membranes, and the\nYoung’s modulus of the 12 nm-thick SrRuO₃ membrane\nwas found to be 34.65 GPa via the buckling method, which is approximately\n21% of the bulk SrRuO₃. The corresponding super-flexibility\nmechanism is attributed to the high defect density and small specific\nsurface area. The SrRuO₃ films maintain the resistivity\nbefore and after transferring in the range of 1.4 × 10^–4 to 5.2 × 10^–4 Ω cm that can be used\nas electrode materials. This work provides a realistic strategy for\nthe super-flexibility transition of the single-crystal SrRuO₃ conductive oxide membranes from brittleness, which paves the way\nfor their application in flexible electronics devices.