Deoxygenation of Y-Ba-Cu-O thin films by reactive ion implantation
Thin films of YBa/sub 2/Cu/sub 3/O/sub 7/ (YBCO), grown by pulsed laser deposition, were implanted with Si/sup +/ ions at energies of 30,60, and 90 keV and at doses ranging from 1/spl times/10/sup 13/ cm/sup -2/ to 3/spl times/10/sup 11/ cm/sup -2/. X-ray diffraction techniques were used to investigate the structural dependence on implant parameters and annealing conditions, while d.c. magnetization was measured to characterize superconducting properties. By implanting only the upper portion of the film, implanted Si/sup +/ ions, near the surface, inhibit the superconductivity by removing oxygen from the bottom YBCO lattice which still retains its original crystal structure.