Large Jc enhancement by ion irradiation for thick YBa2Cu3O7-δ films prepared by photoassisted metalorganic chemical vapor deposition

Thick superconducting films of YBa2Cu3O7-δ grown by photoassisted metalorganic chemical vapor deposition that have shown a decrease of Jc with increasing thickness (>1 μm) have been exposed to ion irradiation in an attempt to enhance Jc. A 4.5 μm thick film irradiated with 1 MeV protons at a dose of 3x1014/cm2 has shown an increase of Jc by a factor of nearly 20 endash 1.7x106 A/cm2 corroborating the proposal that a lack of pinning centers in the grown thick films, due to their high crystalline quality, contributed to the observed decrease of Jc with increasing film thickness. copyright 1997 American Institute of Physics