FORMATION OF SINGLE-CRYSTAL COSI2 BUFFER LAYERS ON SI(100) SUBSTRATESBY HIGH-DOSE CO ION-IMPLANTATION FOR THE DEPOSITION OF YBA2CU3O7-X THIN-FILMS

High quality single-crystal CoSi2 layers have been successfully formed on Si(100) using low energy high dose Co ion implantation followed by subsequent annealing method as a buffer layer for the deposition of Y Ba2Cu3O7-x (YBCO) thin films. Rutherford backscattering spectrometry w ith channeling (RBS-C) measurements showed that CoSi2 layers after ann ealing at temperatures between 850 and 950 degrees C had a minimum yie ld chi(min) of about 3%. X-ray diffraction (XRD) spectra revealed that CoSi2 layers had the same orientation as the Si(100) substrates. Phi scan XRD spectra proved that CoSi2 layers epitaxially grew in the cube -on-cube epitaxial growth mode with respect to the Si(100) substrates. YBCO films and CeO2/YSZ buffer layers were deposited on CoSi2/Si(100) substrates via laser ablation and electron beam evaporation, respecti vely. theta-2 theta, omega, and phi scan XRD spectra illustrated that YBCO films and CeO2/YSZ buffer layers had the epitaxial structure both in a-b plane and along the c-axis. YBCO films grown on this multilaye red structure demonstrated excellent superconducting propel-ties with the zero resistance transition temperature T-c0 of 87-90 K. The transi tion width (Delta T-c) was about 1 K. Orientation and epitaxial crysta lline quality of YBCO films and CeO2/YSZ buffer layers were confirmed by XRD and RBS-C characterization, All films consisted of c-axis orien ted grains. RBS-C spectra indicated a high degree of crystalline perfe ction with a channeling minimum yield for Ba as low as 8%, and interdi ffusion between the YBCO film and buffer layers or between the YBCO fi lm and the substrate was limited. This multilayer system shows the pos sibility for the application of YBa2Cu3O7-x thin films on technical Si substrates in the field of hybrid superconductor-semiconductor techno logy.