Superconducting NdBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin films prepared by the laser ablation method

NdBa/sub 2/Cu/sub 3/O/sub 7-/spl delta//(NBCO) thin films were deposited on (100) SrTiO/sub 3/(STO) substrates by the laser ablation method. The transition temperature of thin films was very sensitive to the deposition parameters such as substrate temperature, chamber pressure, and the distance between target and substrate. Thin films of T/sub c//spl sim/93 K were obtained when we deposited at 770/spl deg/C and 800 mTorr of oxygen pressure. The NBCO thin films were grown epitaxially with c-axis preferred orientation. The critical current density of the thin films was /spl sim/1/spl times/10/sup 6/ A/cm/sup 2/ at 77 K. We have also studied the surface morphology with AFM, and the typical smoothness is /spl sim/3 nm.