Local microwave surface resistance variations of the YBaCuO thin films patterned by selective laser irradiation and plasma fluorination
In this paper, we have studied the planar patterning of the YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin films by laser irradiation and ion plasma treatment. The laser ablated YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin films have been modified either by selective laser irradiation or by plasma fluorination in an atmosphere of CF/sub 4/ to pattern microwave devices. Transport measurements and microstructure analysis have been used to study the effects of the selective laser irradiation or plasma fluorination on the superconductivity of the YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin films. A scanning microwave near-field microscopy has been involved to investigate the local microwave surface resistances of the patterned devices. Enhancement of the microwave surface resistance has been found in the treated regions of the YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin films by selective laser irradiation or plasma fluorination. These results would be helpful in evaluating the microwave performance of the devices.