Evolution of morphology and residual stress of GdBa2Cu3O7??/EuBa2Cu3O7?? quasimultilayers

Aggregate thickness of 800 nm GdBa₂Cu₃O_7-δ/EuBa₂Cu₃O_7-δ multilayers with various layers are obtained by changing each layer thickness. The evolution of surface morphology, epitaxial texture, and residual stress of quasimultilayers GdBa₂Cu₃O_7-δ/EuBa₂Cu₃O_7-δ thin films deposited by pulsed laser deposition on Hastelloy substrates have been systematically investigated with scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction and Raman spectroscopy. SEM images of the YBCO films grown on Hastelloy substrates show smooth and density morphology. X-ray diffraction patterns indicated that superconducting multilayers varying from 2 to 32 layers have good epitaxial texture, but the relatively low temperature leads to weak crystallinity. Raman spectroscopy illustrates a significant change of residual stress as films layers increase from 8 to 16 layers. With an optimization for crystallization processes, better microstructure and superconducting performance of quasimultilayers are expected.