IMPROVED SURFACE SMOOTHNESS OF YBA2CU3OY FILMS AND RELATED MULTILAYERS BY ARF EXCIMER-LASER DEPOSITION WITH SHADOW MASK ECLIPSE METHOD

By simply placing a shadow mask between the target material and substrate, the particle (or droplet) problem peculiar to the excimer laser deposition technique was completely eliminated. It is tentatively called the ''eclipse method'', in which the deposition proceeds through only diffusion. Mirrorlike YBa2Cu3Oy thin films with T(c) as high as 90-93 K were obtained reproducibly by (eclipse) ArF excimer laser ablation on MgO substrates in 0.3 Torr O2 ambient. The growth rate reduction was only 70% under this ambient condition. Even when the pressed-powder targets were employed for deposition, the metal-insulator-superconductor (MIS) layered structure seldom encountered the pinhole problem.