Determination of the topmost atomic layer of NdBa2Cu3Oy thin films by developed total reflection angle X-ray spectroscopy (TRAXS)

Abstract The surface termination layer of c -axis oriented NdBa 2 Cu 3 O y thin films deposited by laser ablation process has been studied by a developed TRAXS method, described as glancing incidence-exit X-ray scattering (GIEXS). Using the SrTiO 3 substrate terminated with a well defined surface, coated with island-like gold layer, we have demonstrated the effectiveness of GIEXS to distinguish the surface atomic layer from their underlying layered bulk crystal. Applying this method to examine the surface atomic layer of NdBa 2 Cu 3 O y thin films cleaned with atomic oxygen beam, we have found that the surface of NdBa 2 Cu 3 O y thin films is predominantly terminated with CuO chain plane.