The preparation of inclined c-axis YBa2Cu3O7-δ sensitive film with the transverse thermoelectric effect based on the flexible metal-based substrate

Abstract

The YBa₂Cu₃O_7-δ-based atomic layer thermopile (ALTP) heat flux sensor, characterized by its high response frequency, has been utilized in scale-model testing within hypersonic ground-based facilities to detect the unsteady fluctuating heat flux caused by the laminar-to-turbulent boundary-layer transition. However, the insert-assembled method and typical single crystal substrate lead to complex operational procedures and measurement inaccuracies. Consequently, preparing high-orientation, c-axis inclined YBCO films on flexible substrate may provide a viable solution for accommodating the irregular surface of models. In this work, the c-axis inclined YBCO films were successfully epitaxially grown on the unoriented metal-based flexible substrate by incorporating the MgO template layer. The epitaxial quality is closely associated with the deposition temperature, where the good crystal quality and biaxial texture (Δχ = 4.31°, Δφ = 10.86°) are obtained under the proper temperature. Additionally, the remarkable transverse thermoelectric effect performance further indicates the successful epitaxial growth of the YBCO sensitive film.