Semiconducting YBCO Thin Films for Uncooled Terahertz Imagers

Abstract:

The terahertz domain (500 GHz - 5 THz) has been object of unceasing research activities, due to the wide range of conceivable applications in these fields. This study focuses on the development of semiconducting YBa2Cu3O6+x (YBCO) thin films to be used as sensitive elements on future uncooled terahertz imagers working on a thermal principle. YBCO thin films have been hollow-cathode sputtered on MgO single-crystals under different conditions. Electrical and structural characterizations have then been carried out. The resistivity of the thin films and the temperature coefficient of resistance (TCR) have been determined. X-ray diffraction and atomic force microscopy analyses have then been performed. If compared with materials currently used as sensing element in commercial near-infrared imagers, electrical characterization shows values of the TCR comparable to amorphous silicon and almost two times better than VOx-compounds.